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Copyright 2007, New Age International (P) Ltd., PublishersPublished by New Age International (P) Ltd., Publishers

All rights reserved.No part of this ebook may be reproduced in any form, by photostat, microfilm,xerography, or any other means, or incorporated into any information retrievalsystem, electronic or mechanical, without the written permission of the publisher.All inquiries should be emailed to rights@newagepublishers.com

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NEW AGE INTERNATIONAL (P) LIMITED, PUBLISHERS4835/24, Ansari Road, Daryaganj, New Delhi - 110002Visit us at www.newagepublishers.com

ISBN (13) : 978-81-224-2549-9

Bio denotes all things which are connected with life. Firstly man has learnt the use of herbsfor treatment and the knowledge of botany becomes essential for the practitioner of medicine.Gradually man has learnt to apply laws of physics and chemistry to living things which has led to theevolution of sciences of biophysics and biochemistry. In recent years, there has been rapid progressin the field of the health care. The need to effectively utilize high technology equipment and systemsin the health care necessitates the expertise of clinical engineers, hospital physicians and computerscientists. Hardly any patient today would pass through a hospital or even a family physicianschamber without the use of this technology.

The knowledge of basic engineering and the need of biomedical engineers in health care isincreasingly accepted. The biomedical engineering is the inter marriage of engineering and medicine.The biomedical engineering as a subject has been introduced in the engineering courses to equip theengineering graduates to work in the health care industry. It is, therefore, essential for engineeringstudents of almost all disciplines to have a sound knowledge of biomedical engineering. This book isdesigned to explain the fundamentals of biomedical engineering in the areas of biomechanics, biofluidflow, biomaterials, bioinstrumentations and in use of computing in biomedical engineering. Thoughthis book is chiefly based on the syllabus of Uttar Pradesh Technical University, but an effort hasbeen made to cover the syllabus of several other universities as well as based on my experience ofteaching.

I have endeavoured to present a systematic explanation of the basic concepts of the biomedicalengineering by firstly introducing the topics of anatomical terms and planes, terms related to movementsmedical terminology, histology and physiological systems of the body. A large number of objectivetype questions are included to enhance the understanding of the principles of theory.

I express my gratitude to Dr. Jasdev Singh Sawhney, FRCR and Dr. Pooja Sachdev SawhneyMRCP for their valuable suggestions which have helped me immensly in conceptualizing and writingthis book. I am also thankful to my doctoral guide, Dr. S. Prasad, NIET Greater Noida for moralsupport. I am also thankful to Dr. Sujay K.Guha, SMS, IIT kharagpur who has been my inspirationin the field of biomedical engineering.

I am also thankful to Dr. V.K. Goswami and the faculty of GNIT, Greater Noida specially Mr.Devraj Tiwari of Mechanical, Prof O.P. Sharma and Mr. Manish of Information Technology, Mrs.Minakshi Awasthi of Physics and Mr. S.D. Nautyal of library for their contributions.

Above all, I wish to record my sincere thanks to my wife, Jasbeer Kaur for her patienceshown throughout the preparation of this book. I am also thankful to the staff of New Age Publishers

who have associated with the completion of this book. Last but not least, I want to thank Mr. K.K.Aggarwal, chairman and Dr. A.M. Chandra, Director of Lord Krishna College of Engineering,Ghaziabad where I joined recently for their constant encouragement.

I would appreciate receiving constructive suggestions and objective criticism from studentsand teachers alike with a view to further enhancing the usefulness of the book by e-mailing atchanni_sawhney@hotmail.com

G.S. SAWHNEY

Preface v

1. Introduction 1

2. Concepts of Physics, Mechanics and Fluid Mechanics 23

3. Biomedical Engineering 33

4. Biomechanics of Bone 38

5. Biomechanics of Soft Tissues 48

6. Skeletal Joints 52

7. Mechanics of the Spinal Column 57

8. Mechanics of Upper Limbs 62

9. Mechanics of Lower Limbs 74

10. The Cardiovascular System and Blood Flow 89

11. The Respiratory System 111

12. Kidney and Blood Flow 122

13. Prosthesis and Therapeutic Devices 127

14. Orthosis 141

15. Metallic Biomaterials 146

16. Polymeric Biomaterials 151

17. Bioceramics 158

18. Composite Biomaterials 162

19. Biogradable Polymeric Biomaterials 165

20. Orthopedic Prostheses Fixation 167

21. Physiological Signals and Transducers 169

22. Signal Processing 181

23. Digital Image Acquisition and Processing 186

24. Radiography 194

25. Computed Tomography 204

26. Magnetic Resonance Imaging 213

27. Ultrasound Imaging 219

28. Radioisotopes and Radiotherapy 226

29. Nuclear Medicine 232

30. Health Care Information and Communication 235

31. Biotelemetry 239

32. Application of Computer in Medicine 244

33. Telemedicine 249

34. Database Design Topologies and Network Security 255

Bibliography 260Index 262

If only tool in your bag is a hammer then every problem in the world appearsto be a nail.

1. The body is made up of the head, trunk andlimbs. The trunk consists of the neck, thorax(chest) and abdomen (belly). The lower partof the abdomen is the pelvis. This word is

also used for the bones of the pelvis. Thelowest part of the pelvis or in other wordsthe lowest part of the trunk is the perineum.The central axis of the trunk is the vertebralcolumn, and the upper part of it (cervicalpart) supports the head.

Head

Neck

Thorax

Abdomen

Thigh

Leg

Foot

Planter surface

Arm

Fore Arm

Ulnar side PelvisPerineumHand

Dorsal surface

Palmar surface

Dorsal surface

Radial side

ANATOMICAL TERMS AND PLANES

Anatomical Terms

2. The main parts of the upper limb are thearm, forearm and hand. Arm in strictanatomical term means the upper arm (thepart between the shoulder and elbow)however, this word is commonly used forthe whole of the upper limb.

3. The main parts of the lower limb are thethigh, leg and foot. Here also leg in strictanatomical form means the lower leg (thepart between the knee and foot) but theword is commonly used for whole of thelower limb.

4. In order to describe the positions ofstructure in human anatomy, the body isassumed to be standing upright with the feettogether and the head and eyes looking tothe front with the arms straight by the sideand the palms of the hands facing forwards.This is the anatomical position andstructures are always described relative toone another using this as the standardposition. This is also applicable even whenthe body is lying on the back to bed or whenlying on a dissecting table.

5. The Median plane is an imaginary verticallongitudinal line through the middle of thebody from front to back, dividing the bodyinto right and left halves. The sagittal planeis any plane that is parallel to the medianplane. The adjective medial means nearerto the median plane, and lateral meansfarther from it. Thus we can say inanatomical position, the little finger is onthe medial side of the hand and the thumbis on the lateral side, similarly the great toeis on the medial side of the foot and the littletoe on the lateral side. If we consider forearmwhich has two bones with radius bone onthe lateral side and ulna bone on the medialside, then the adjective radial and ulnarcan be used instead of lateral & medial.Similarly in the lower leg where there aretwo bones, the fibula on the lateral side andthe tibia on the medial side, the alternativeadjectives fibular and tibial can be used.

6. Coronal planes are imaginary planes at rightangles to the median plane. Horizontal ortransverse planes are at right angles to boththe median and coronal planes.

Coronal p lane

M ed ian plane

Horizon ta l o r

T ransverse p lane

Planes

7. The terms anterior and posterior are usedto indicate the front or back of the bodyrespectively. Therefore we have anterior andposterior view of the body or any part ofbody or organ. It is also used to describethe relationship of two parts. One is said tobe anterior or posterior to the other if it iscloser to anterior or posterior to the bodysurface. Hence on the face, the nose isanterior to the ears and the ears are posteriorto the nose. Sometimes ventral is usedinstead of posterior.

8. In describing the hand, the term palmarand dorsal surfaces are used instead ofanterior and posterior. Similarly in describingthe foot, the plantar and dorsal surfaces,are used instead of lower and upper surfaces.

9. The terms proximal and distal describethe relative distances from the roots of thelimbs. The arm is proximal to the forearmand the hand is distal to the forearm.

10. The terms superior and inferior meansnearer the upper or lower end of the bodyrespectively. Hence the nose is superior tothe mouth and, inferior to the forehead.Superficial means near the skin surfaceand deep means farther away from thesurface. The terms internal and externalare used to describe the relative distance ofa structure from the centre of an organ orcavity. Ipsilateral and contra-lateral areused for parts on the same side or not ofthe body. Hence, left hand and left foot are

ipsilateral while the left biceps branchiimuscle and the right rectusfemoris muscle,are contralateral. The supine position ofthe body is lying on the back and the proneposition is lying face downward.

1. Wherever two or more bones meet, it isknown as a joint. The degree of mobilityvaries from joint to joint. Some joints haveno movement (as in bones of skull), somehave only slight movement (as in vertebrae)and some are freely morable. Thesemovements are made in any of three planesas explained above. Different terms are usedto describe the movements as explainedbelow.

2. Flexion is a movement that takes place ina sagittal plane. It is infact folding of thebones so as they may come nearer. Forexample, flexion of the elbow joint bring theanterior surface of the forearm to the anteriorof the arm. It is usually an anteriormovement but it can be posterior movementalso as in the case of the knee joint.Extension means unfolding or straighteningthe joint. The movement usually takes placein a posterior direction. However, flexionand extension of trunk takes place in thecoronal plane (lateral).

TERMS RELATED TO MOVEMENTS

Extension Flex ion

Flex ion

Extension

Flex ion

ExtensionShou lder jo in t E lbow join t Knee joint

Flexation and Extension

3. Abduction of a limb is the movement awayfrom the midline of the body in the coronalplane. Adduction of a limb is the movementtowards the body in the coronal plane. In

the fingers and toes abduction signifies thespreading of these parts and adductionindicates the drawing together of these parts.

4. Rotation is a term applied to the movementof a part of the body around its long axis. Itcan be.

(a) Medial rotation, which is themovement that takes place in the

Abduction

Adduction

Shoulder Hip Joint Fingers

Abduction

Adduction

Adduction

Abduction

Abduction and Adduction

anterior surface of the part when facingmedially.

(b) Lateral rotation is the movement thattakes in the anterior surface of the partfacing laterally.

Medical Rotation of Shoulder Rotation of Shoulder

(c) Pronation of the forearm is medialrotation of the forearm in such a mannerthat the palm faces posteriorly.

(d) Supination of the forearm, is a lateralrotation of forearm from the pronatedposition so that palm of the hand comesto face anteriorly.

Pronation of Forearm Supination of Forearm

5. Circumduction, is the combination of fourmovements which is in sequence of themovements of flexion, extension, abductionand adduction.

6. Inversion is the movement of the foot sothat the sole faces in a medial direction whileeversion is the opposite movement of thefoot so that the sole faces in a lateraldirection.

Circumduction of ShoulderJoint

Inversion of Foot Eversion of Foot

MEDICAL TERMINOLOGY

1. Engineers and technicians working inmedical field have to learn enoughphysiology, anatomy and medicalterminology to be able to discuss problemsintelligently with members of medicalprofession. They face great difficulty in

learning medical terminology. However witha few simple rules, medical terminology, canbe understood more easily. Most medicalwords have been derived from latin andGreek. Most words consist of a root or basewhich is modified by a prefix or suffix orboth. The root is often abbreviated whenthe prefix or suffix is added.

PREFIXES

Prefix Stands for Prefix Stands for

a without or not mat bad

ab away from medio Middlead toward meta beyond

an absence of micro smallante before ortho straight, correct

antero in front para besideoxy containing oxygen

anti against patho disease

bi two peri outsidedia through poly many

dys painful pseudo falseendo within retro backward

epi upon sub beneatheu good supra above

ex away from tachy fastexo outside trans across

hyper overhypo under or less tri threeinfra below ultra beyond

intra within uni single, one

SUFFIXES

Suffix Stands for Suffix Stands for

algia pain emia bloodcenteses puncture iasis a processclasia remedy itis inflammationectasis dilation oma swelling, tumorectomy cut sclerosis hardeningedema swelling

Roots Stands for Roots Stands for

adon gland gaster stomach

arteria artery haemo/hemo bloodarthros joint hepar liver

branchion arm hydro waterbranchus windpipe larynx throatcardium heart nephros kidney

cephalos brain neuron neuroncolon intestine odynia pain

costa rib os/osteon boneCranium head ren kidney

derma skin spondylos vertebraepithelium intestine stoma mouth

ostium orifice, mouth thorax chestpharynx throat trachea windpipe

phlebos vein vene veinpleura chest vesica bladderpsyche mind

pulmones lungspyelos pelvis

2. Examples of synthesis of words

(a) peri + cardium = pericardium

= outside the heart

(b) an + emia = anemia

= absence of blood

(c) hypo + oxygen = hypoxia

= lack of oxygen

(d) hyper + ventilation = hyperventilation

= over breathing

(e) tachy + cardia = tachycardia

= rapid heart action

(f) intra + venous = Intravenous

= within vein

ROOTS

(g) Intra + vascular = intravascular

= within blood vessel

(h) arthros + itis = arthritis

= inflamation of joint

(k) hyper + tension = hypertension

= high arterial blood pressure

(l) patho + phobia = pathophobia

= fear of disease

(m) sclero + dermatitis = sclerodermatitis

= hardening of skin

(n) gastroenteritis = gastro + intestine + ities

= inflammation of the mucous membranes of both stomach andintestine

(o) Arteries = Aeir (air) + tercm (to keep).It is a greek word. After death thearteries (blood vessels to take blood toorgans) are usually empty of bloodwhereas the veins (blood vessels totake blood to heart) are full of clottedblood. The ancient concluded from this,that the arteries carried air. Hence thename given to these vessels as arteries.

(p) Robotic = Robota (Slave) + ic (Like).In 1921, Czech dramatist, KARELCAPEK published ROSSUMsUNIVERSAL ROBOTS. Based on this,the word robot has been coined forsomething working as slave. A Robotis any mechanical device operatedautomatically to perform in seeminglyhuman way. Current research effortsfocus on creating a smart robot thatcan hear, touch, taste & consequentlymake decision. Robots do not have to

look like humans and it is functions,not form which matters. Robots havecapability to interact with humans viasynthesised speech. They have visionsensors to identify obstructions, roadblocks and detect motion in theenvironment. They can navigate andmake documentation. They can beprogrammed to make decisions.Robotic intensive care cart is beingused in intensive care unit. Robots canbe used as device to provide technicalaids to the handicapped.

1. In this book many medical words have beenused which are unfamiliar to the readers.The glossary of medical words which willbe used in this book is presented inalphabetical order.

MEDICAL GLOSSARY

Bifurcation Branching as in blood vessel.

Bioelectricity Electrical phenomenon thatappear in living tissue.

Brachial Relating to the arm or acomparable process.

Bradycardia A slow heart rate.

Bronchus Bronchial tubes, (air passage)i.e., two branches of tracheagoing into the right and theleft lungs.

Bundle of His A small band of cardiacmuscle fibers transmitting thewave of depolarization fromthe atria to the ventriclesduring cardiac contraction.

Capillaries Smallest vessels of the bloodvascular system connectingarterioles with venulesand forming or networkthroughout.

Cardiac Pertaining to the heart

Cardiology The study of the heart aboutits action and diseases

Cardiovascular Relating to the heart and bloodvessels.

Catheter A tubular device inserted inany passage of body to keepit open or to inject orwithdraw fluid.

Cell A smallest living mattercapable of functioning as anindependent unit.

Cerebellum A part of brain to coordinatemuscle and to maintainequilibrium.

Anatomy A study of the structure ofthe body and the relationshipof its constituent parts toeach other.

Alveoli Air sacs in the lungs formedat the terminals of abronchiole. It is the thinmembrance of the alveoli thatallows oxygen to enter theblood stream.

Aorta The great trunk artery thatcarries blood from heart to bedistributed by branch arteriesthroughout the body.

Aortic valve Outlet valve from leftventricle to the aorta.

Arrhythmia An alteration in rhythm of theheart beat either in time orforce.

Arteriole One of the small terminalbranch of an artery that endsin capillaries.

Artery A vessel through which theblood is pumped away fromthe heart.

Atrio ventricular Located between an atriumand ventricle of the heart.

Atrium A main chamber of the heartinto which blood returns fromcirculation

Auscultation The act of listening forsounds in the body.

Axon A never cell process whichconducts impulse away fromthe cell body of a neuron.

Collagen Literally meaning is glueproducing. The major portionof the white fibers ofconnective tissue and bone.

ComputerisedAxial tomography (CAT) : A technique combining

X-ray and computer technol-ogy for visualisation ofinternal organs and bodystructure.

Coronary arteryand sinus vessels carrying blood to &

from the walls of the heartitself.

Cortex Outer part of an organ orbody structure.

Cranium The part of the head thatencloses the brain.

Defibrillation The correction of rapidirregular contraction of theheart

Diastole Dilation of the cavities of theheart as they fill with the bood.

Diastolic Pertaining to the diastole.Diastolic blood pressure islower.

Dicrotic Second expansion of arterythat occurs during the diastoleof the heart (a dicrotic notchin the blood pressure wave)

Electro cardiogram

(ECG) A record of the electricalactivity of the heart.

Embryo An organism in early stagesfrom conception.

Enzyme A protein secreted by cellsthat acts as a catalyst toinduce chemical changes inother substances and itselfremains unchangedby the process.

Epilepsy A disorder marked bydisturbed electrical rhythmsof the nervous system.

Fluoroscopy Process to observe internalstructure by X-ray.

Hemorheology The science of rheology of theblood, the relation of pressure,flow volume and resistance toblood vessels.

Heparin An acid in tissue which makethe blood incoaguable.

Hormone A chemical substance formedin one organ and carried inblood to another organ.Depending on the specialityof their effects, hormonescan alter the functional activityand sometimes structure ofone or more organs.

Hypoxia Lack of oxygen.

Inferior venacava Main vein feeding back to the

heart from systemiccirculation below the heart.

In-vivo In living body chemicalprocess occuring within cell.

Ischemic A localized anaemia due to anobstructed circulation.

Isometric Having same length. A muscleacts isometrically when itapplies force withoutchanging its length.

Isotonic having same tone. A muscleacts isotonically when itchanges length withoutchanging much the force itexerts.

Korotkoff sounds Sounds produced by suddenpulsation of blood beingforced through a partiallyoccupied artery and heardduring ausculatory bloodpressure determination.

Latency Time delay between stimulusand responses

Liver the largest gland of the bodylying beneath the diaphragm.It is irregular in shape andweight from 3 to 3 poundsor about 1/40 the weight ofthe body. It secretes the bileand it is also of greatimportance in bothcarbohydrate & proteinmetabolism.

Lung The organ of respiration inwhich aeration of the bloodtakes place.

Membrane A thin layer of tissue thatcovers a surface or divides aspace or organ

Metabolism The sum of all the physicaland chemical processes bywhich the living organisedsubstance is produced andmaintained.

Mitral valve Valve between the left atriumand ventricle of the heart.

Motor A muscle, nerve or centre thateffects or producesmovement.

Myelin A fat like substance forminga sheath around certain nervefibers

Myocardium The walls of the chamber ofthe heart which contain themusculature which actsduring the pumping of blood.

Myograph An apparatus for recordingthe effects of the muscularcontraction

Necrosis Death of tissueNerve A cord like structure that

conveys impulse from onepart of the body to another.

Neuron A nerve cell.

Orthosis Making straight, thecorrection of maladjustment.

Oxyhaemoglobin A compound of oxygen andhaemoglobin which is formedin lungs whereby oxygen iscarried through the arteries tothe body tissue.

Pathology The science and study ofdisease, its causes and cure.

Perfuse To pour over or through.Permeate To pass through the poresPneumograph The recording of the thoractic

movement or volume changeduring respiration.

Prosthesis Artificial substitution of amissing or diseased part thelike lower limb.

Protein Part of cell and each cell is three-fourth protein.

Pulmonary Associated with lungsPulse pressure The difference between systolic

and diastolic blood pressure.

Radioisotope An isotope that is radioactiveproduced artificially from thebasic element by the action ofneutrons, protons, deutrons oralpha particles in cyclotron bychain reaction. These are usedas tracer with stable element(labeled) by injecting in body tostudy the functioning of organs.

Radiology The chief X-rays methods usedin the examination of the chestwhich are fluoroscopy,radiography, tomography andbronchography.

Semi lunarpulmonary valve Outlet valve from the right

ventricle into the pulmonaryartery.

Sinoatrial The pacemaker of the heart,cardiac muscle which isresponsible for initiating eachcycle.

Sphygmomanometer Instrument for measuring blood

pressure (arterial).Spirometer Instrument for measure air

which is entering and leaving thelungs.

Spleen It is a blood forming organ inearly life. It is storage organ forcorpuscles and because of largenumber of macrophages acts asa blood filter.

Stenusis Narrowing of a duct or canal.Stroke volume Amount of blood pumped

during each heartbeat.Superior venacava Main vein feeding back to the

heart from systemiccirculation above the heart.

Systemic Pertaining to or affecting thebody as a whole.

Systole The contraction specially ofventricles during which bloodis forced into the aorta andthe pulmonary trunk.

Tachycardia Rapid heart action.Tendon A fibrous cord or band that

connects a muscle to a bone.It consists of tissue fasciclesof very densely arrangedalmost parallel collagenousfibres.

Thorax The part of the body betweenneck and abdomen.

Thrombus Clotting of blood within ablood vessel

Tissue Similar cells united in theperformance of a partcularfunction.

Trachea The main trunk of the systemof tubes by which air goes inor comes out of the lungs.

Tricuspid valve The valve connecting rightatrium to right ventricle.

Ventricle A chamber in heart whichreceives blood from atriumand forces it into arteries.

Venule A small vein.

1. All organs of the body are formed of tissues.A tissue is a collection of similar type of cells,which are associated with some intercellularmatrix (ground substance) governed bysome laws of growth and development.These cells are adopted to perform the samefunction or functions. Tissues are usuallyclassified into four main categories:

(a) Epithelial tissue

(b) Connective tissue

(c) Muscular tissue

(d) Nervous tissue

2. Epithelium : It is a lining or covering tissue.It is a sheet of cells that cover externalsurface or lines of internal surface of thebody. It can be simple, pseudostratified orstratified epithelium.

3. Connective tissue: It has few cells and alarge amount of non living ground substanceor matrix. It can be:

(a) Connective tissue proper

(b) Skeletal tissue

(c) Fluid connective tissue

4. Connective tissues proper as name suggests,connect and anchor parts and give supportto the body and its organs. For this reason,connective tissue is also known assupporting tissue. Connective tissue andskeletal tissue (cartilage and bone) have toperform mechanical functions.

5. The skeletal tissue includes the cartilages andthe bones which form the structure of thebody skeleton. The bones and cartilages haveconsiderable rigidity. This is a feature whichenables them to act as levers which is ofgreat importance in the movement of limbs.The bones and the cartilages also providesurfaces for the attachment of muscleswhich provide force for the movement.Skeleton also protects the internal organsbesides giving shape to the body. Cartilages

are four types. Hyaline cartilage is boundedby fibrous membrane which is supplied byblood vessels and through it nutritivesubstances diffuse into the cartilage.Cartilage grows by the addition of new layerson the outside. Hyaline cartilage occurs atthe ends of the long bones. It has greatresistance wear and covers the articularsurfaces of nearly all synovial joints. Yellowelastic cartilage has great elasticity due tothe presence of large number of yellowelastic fibers. It is found at the end of thenose and in the pinna of the ear. Calcifiedcartilage has its matrix impregnated withcalcium salts. It is found in the pelvis andat the head of the humerus and femur bones.White fibrous cartilage has a large numberof white fibers. It is found in the discs ofvertebral hyaline cartilage and fibrocartilagefound to calcify or even ossify in later life.Bone is a connective tissue in which thematrix is inpregnated with various saltswhich contribute to about two third of itsweight. Bone is developed by two methods(1) membranous (2) endochondral. In firstmethod the bone is developed directly froma connective tissue membrane. For example,the bones of the vault of the skull aredeveloped rapidly by the membranousmethod in the embryo. In the second, acartilagious model is laid down which isreplaced by bone. The long bones of thelimbs are developed by endochondralossification. Bones have fine canals whichjoin with blood vessels and bone marrow.At birth, the marrow of all the bones of thebody is red and hematopoietic (formingblood cells). The blood forming activitygradually lessens with age and red marrowis replaced by yellow marrow.

6. Fluid connective tissue: Blood is liquidconnective tissue. It is red coloured fluid. Itconsists of liquid portion which is calledplasma and of three different kinds of cellswhich are red blood corpuscles(erythrocytes), white blood corpuscles

HISTOLOGY

(leucocytes) and platelets (thrombocytes).Plasma is the liquid portion of the blood ofwhich it forms about two-third and containsabout 80% of water. It is almost colourlessclear fluid and contains an everchangingvariety of substances in solution andsuspension. Among the various substancespresent in the plasma are gases, absorbedfood material, inorganic salts, vitamins,metabolic waste products, hormones, antitoxin and a soluble blood protein calledfibrinogen. The cytoplasm of red corpusclescontains a pigment, the haemoglobin whichmakes these cells appear red. In bulk thesecells give blood its red colour. Thehaemoglobin combines readily withoxygen to form an unstable compound,oxyhaemoglobin. In the tissues it breaks upreleasing the oxygen. Here it combines withcarbondioxide to form an unstablecompound, carboxy haemoglobin, whichbreaks up in the lung, releasingcarbondioxide for expiration. Haemoglobin,therefore, transports the gases and as suchplays a vital part in respiration. The redcorpuscles are formed in liver and spleenwhich also destroy the worn out corpuscles.As these are nucleated, they live for a prettylong time. The white blood corpuscles(leucocytes) are small, semitransparent,nucleated and amoeboid cells. These cancrawl out between neighbouring endothelialcells and hence are found in every nook andcorner of the body. At part of body havinginfections, they accumulate in very largenumbers and serve to defend the bodyagainst the disease germs. They are able toeat bacteria and other germs in an amoebalike manner. This process is known asphagocytosis and hence they are known asphagocytes. Some of the WBC are killed bybacterial acids. Thus they may accumulateat the seat of infection as living or deadbacteria, leucocytes and disintegrating cells.All these form a whitish or yellow mass

which is called pus. Leucocytes are alsouseful in transporting waste particles and fatglobules. These are produced in the bonemarrow and lymphatic glands and aredestroyed in the lymph organs.Thrombocytes or platelets contain achemical which plays an important role inthe clotting of blood. The various functionsof blood are :

(a) Transport of gases : RBC combines withoxygen to form oxyhaemoglobin whichbreaks up and release oxygen in tissues.In tissues, RBC combines with carbon-di-oxide to form carboxy haemoglobinwhich breaks up in the lungs to releasecarbondioxide for expiration.

(b) Transport of food material: All theabsorbed food circulated by the bloodtill it is taken up and used by tissue cells.

(c) Transport of substances: Many othersubstances such as enzymes, hormonesand anti toxins are transported by theblood to the places where they arerequired.

(d) Defence against disease: This iseffected in two ways. Firstly the whiteblood corpuscles feed on diseasegerms. Secondly blood possessescertain antioxins which unite chemicallywith toxins and then neutralize them.

(e) Equalization of the body temperature:As the blood circulate throughout thebody, it brings about an equalization ofthe body temperature by transferringheat from one part to another.

(f) Transport of metabolic wastes: Thenitrogenous waste material is carried bythe blood to the liver where it isconverted into urea. The later is nowcarried by the blood to the kidney whereit is removed out along with the urine.

(g) Clotting of blood: Blood has a solublesolution called fibrinogen which isconverted into a mesh work of fine

threads of insoluble fibrins. In the meshof fibrins, various types of corpusclesget entangled to form a blood clot whichis also known as coagulation. Theconversion of fibrinogen into fibrin isaffected by the action of an enzymecalled thrombin. Free thrombin is notpresent in the blood but it is formed byits precursor (inactive enzymeprothromboplastin) in presence ofcalcium ions. Calcium ions are presentin blood but free thromboplastin isabsent in blood. However it is presentin other solid tissues. Hence when aninjury occurs, thromboplastin isreleased by the injured tissues. Thethromboplastin then acts with calciumupon the prothrombin, changing it tothrombin. The thrombin then acts uponthe fibrinogen and converts it to fibrin.

7. Muscular tissue: It consists of cells in theshape of fibres of different lengths. Inter-cellular elements are almost absent. Themuscular tissues are of three types :

(1) Striped or voluntary

(2) Unstriped or involuntary

(3) Cardiac

The striped muscles are under thecontrol of will and they are wide andnontapering. In the striped muscle,fibres are united in parallel bundleswhich is continuous with the connectivetissue sheath surrounding the tendonsthat unite the muscle to the skeleton.Unstriped muscles are made ofelongated, spindle shaped, flattenedfibres which are rarely forked at theends. The number of unstriped musclefibres are united together by a minutequantity of intercelluar substance intoa thin and flat band and a number ofsuch bands are bound together byconnective tissues into a larger bundle.The unstriped muscles are not in thecontrol of will and they are found inthe alimentary canal, the lungs and theblood vessels. The cardiac muscles arefound only in the wall of the heart. Thestructure is somewhat inbetweenstriped and unstriped muscles. Thesemuscles contract rhythmically andthese muscles are immune to fatigue.

Nucleus Nucleus

Nucleus

8. Nervous tissue: They consists of

(1) nerve cell

(2) nerve fibre.

Nerve cells are known as neurons.

Each neuron consists of a cell bodyfrom which arises a system ofbranching fibres. The number of fibresis variable. On this basis, neurons areclassified into three types:

Striped Muscle Unstriped Muscle Cardiac Muscle

(1) neurons with many processes arecalled multipolar.

(2) neurons with two procesess arising atopposite poles are known as bipolar.

(3) neurons having two processes arisingfrom the same pole are known asunipolar. The cytoplasm of each neuroncontain a large and spherical nucleus,large number of dark staining minuteparticles (Nissl Granules) and numerouscytoplasmic strands known asneurofibrillae. Neurofibrillae help in thepassage of the nerve impulse.

PHYSIOLOGICAL SYSTEMS OF THE BODY

1. In our body, we have mechanical, electrical,chemical, thermal, pneumatic, hydraulic andmany other types of system. Each systemcommunicates internally with other systemsof the body and externally it communicates

with surroundings. We have a multi levelcontrol system with its communicationnetwork which organises these internalsystems to perform many complexfunctions. We are able to sustain our livesdue to organised operations of all theseinternal systems and their varioussubsystems. In medical terms, a study ofthe structure of the body and the relationshipof its constituents parts to each other isknown as Anatomy while the study offunction of these parts as a system is knownas physiology. The major functionalphysiological systems of the body are:

(a) The cardiovascular system(b) The biochemical system(c) The respiratory system(d) The nervous system(e) The excretory system(f) The locomotor system(g) The digestive system

Communication with Energy and Mass Transfer with Surroundings

Mass (M )2Solid WasteLiquid WasteExpired airPerspiration

Mass (M )1Food IntakeLiquid IntakeInspired Air

Energy (E )2Body movementTactile sensation

Energy (E )1Light visionVibration (hearing)Flow (smell)

2. The cardiovascular system: Thecardiovascular system is a closed hydraulicsystem. It has heart and blood vessels. Theheart works as a four chamber pump. Theblood vessels are flexible and sometimeselastic tubing of varying sizes. The tubings

Cardiovascular system

Righ t a trium R ight ventric le Pulm onary a rte ry

Left Le ft Pu lm onary Lungsventricle a tr ium ve in

Aorta

change their sizes to control blood pressure,for example arteries and arterioles. Certaintubings act as reservoirs as they can controltheir volume as per the requirements by asystem of valves and variable resistance toflow by constriction and dilation of thecontrol blood tubings. These tubings areveins and they take blood back to heart. Theheart acts as two functionally isolated twostages pumps working in parallel. In firststage of each pump, the blood is taken intothe reservoirs (atriums) from the systemand it is pumped into second stage reservoirs(ventricles). The action of the second stageis so well coordinated that the blood ispumped into the system immediately whenit is received from the first stage. The circuitof the blood is shown in the diagram. Rightside of the heart collects blood from the

hydraulic system through veins and pumpsit to the lungs for oxygenation. The left sideof the heart receives blood from the lungs(oxygenation system), and pumps it intothe main hydraulic system which is formedby the various organs of the body. The heartrate and stroke volume are constantlychanged to control the flow of the blood inthe system to meet the requirements of bodyparts. The blood performs all functions aselaborated in para 25 of this chapter. Theblood flows in laminar manner. Superiorvena cava is a large venous channel whichcollects blood from the upper half of thebody and delivers into the right atrium. Ithas no valve. The inferior vena cava (largerthan superior vena cava) also opens intoright atrium. It returns the blood to the heartfrom the lower half of the body. Since theblood in the inferior vena cava has to flowagainst gravity at times, special one wayvalves are located in it to prevent gravityfrom pulling blood against the direction offlow. The cardiac output flow rate andvolume of the fluid at various places in thebody are important indicators for properfunctioning of the system.

Righ t A trium Left Atrium

Righ t V entricle Left Ventr ic le

To Lungs To A orta

From veins From lungs

Heart Works a Pump

Blood Circuit

18 FUNDAMENTALS OF BIOMEDICAL ENGINEERING

3. The biochemical system: There are manychemical systems in our body that produceenergy for the functioning of our body. Theenergy is required for growth, bodyfunctions and body repairs. These chemicalsystems are interconnected and these canbe considered as the subsystems of a veryefficient chemical factory. There is a singlepoint intake of fuel (food, water and air) forthis factory which is also source for allchemical reactions which are taking placeinside the body. This chemical factory alsocontains all monitory devices which areessential to carry out necessary control foreach chemical operation. The waste disposalsystem is also a part of this biochemicalsystem.

4. The respiratory system: The respiratorysystem is a pneumatic system which ensuresexchange of gases by a biological processwhich is termed respiration. The bodyrequires oxygen to combine with carbon,hydrogen and other nutrients to produce heatand energy for sustenance of life. The entireprocess of taking inside oxygen fromsurroundings, transporting it to body cells,removing the carbondioxide from the cellsand pushing out the carbondioxide intosurrounding is called respiration. Air entersthe lungs through air passages which includethe nasal cavities, pharynx, larynx, trachea,bronchi and bronchioles. The lungs areelastic bags located in a closed cavity, calledthe thorax. The diaphragm is a special bellshaped muscle located at the bottom of theclosed cavity. When this diaphragmcontracts, thorare is pulled downward,enlarging the closed cavity. The resultantincrease in the volume of the closed cavity,a negative pressure (vacuum) is createdwhich is relieved by air entering the lungsfrom the surroundings. When the diaphragmmoves up and reduces the volume of thethorax, the used air with carbon dioxide ispushed out of the lungs. Oxygen is taken

into the blood from the incoming air in about300 million alveoli present in the lungs. Theoxygen and haemoglobins in blood formoxyhaemoglobins and carbondioxideremoved from the blood is pushed out fromlungs to the surroundings. An automaticcontrol system maintains pneumatic pumpoperation (rate of contraction of diaphragm)at a speed that is adequate to supply oxygenand to remove carbondioxide as required bybody. It is also possible to accelerate ordeacelerate the operation of the pneumaticpump by manual control whenever it isrequired. Automatic control returnswhenever manual control is not applied.

5. The nervous system: The nervous systemconsists of control and communicationnetwork which coordinates the functions ofall parts of the body. The brain is the centralinformation processor and it works as acomputer. It has memory, power tocompute, capability to make decisions andinnumerous input, and output channels forcommunication. These channels formcomplicated networks with manyinterconnections (nodes) which take singnalsfrom a large number of sensory devices(each sensory device detects light, sound,pressure, heat and chemicals) to the brain(computer) for analysis. Some network isagain used to take the output control signalsfrom the brain to the motor units of themuscles to carryout the desired motion orto exert force. The nerves form signal linesto carry signals (informations) generated bythe nerve action potentials (sensory devices)to the brain and same signal lines are usedto carry control signals generated by thebrain for the motor units. In addition to thecontrol of the brain, a large number of simpledecision making devices in the form of spinalreflexes are present in the body to controlindependently some motor devices fromcertain sensory inputs. Example of this is

INTRODUCTION 19

the Portal system which consist of vein andcapillary network.

6. The excretory system : It consists of allorgans that are responsible for the removalof waste products formed by metabolism inthe organisms. The kidneys are the majorexcretory organs in man. The left kidney islocated at slightly higher level than rightkidney, one on each side of the vertebralcolumn. The kidneys have bean shape andthey are also called renes from which it isknown as rent. The renal tubules act as filtersto remove from the blood (1) Excess water(2) Urea and uric acid (3) Excess mineralsalts (4) Yellow pigments from the bile. Themixture of these substances forms urine.When the human kidneys fail to function,the urine accumulates in the blood resultingdeath of the person from toxic poisoning.

7. The locomotor system: The systemprovides locomotion or movement to thebody. Bones and joints play an important rolefor this system. Statics and dynamics of themusculoskeletal system; forces and motionsacting in the skeletal system; forces andmovements within the body; behaviour ofbones, tendons, ligaments and cartilages forstress and strains; and prosthesis design etc.will be covered in details in later chapters.

8. The digestive system: It includes all organsthat help in ingestion, digestion, absorptionand egestion of undigested food. It includesthe alimentary canal and asociated glands likeliver and pancreas etc. The liver is the largestgland in the body. It is located on the rightside, just under the diaphragm. It hasirregular shape and it weighs 3 to 3 pounds(1/40th the weight of the body). It secretesbile juice which plays an important role inmetabolism of both carbohydrate and protein.The nitrogenous waste material is carriedby the blood to the liver where it isconverted into urea. Bile pigments arederived from the breakdown of hemoglobin

from worn out red blood corpuscles. Bilepigments colour undigested food. The otherimportant gland is pancreas which secretedigestive pancreatic juice and discharge itinto intestine. This is done by exocrine partof the pancreas. The endocrine part secreteshormones like insulin. Insulin promotesglucose utilization, protein synthesis and theformation and storage of neutral lipids.Insulin is given to the persons suffering fromdiabetes.

9. Cell, DNA and atoms: Our body possessnumerous cells (almost 10,000 trillion) ofalmost some few hundred varities. Each cellperforms an important role to keep us fit.All activities like standing, walking, talkingand playing are possible through these cells.The cells extract nutrients from food,distribute the energy and remove the wastefrom the body. They also fight againstbecteria and billion of cells die daily in thisprocess.

10. Inside every cells is a nucleus which has 46chromosomes (23 come from father and 23come from mother). Chromosomes carryall instructions necessary for our growth andto maintain us. They contain long strandsof chemical called DNA.

11. In microscopic level, each cell of our bodyis made of atoms. We have in our bodyabout 63% by hydrogen atoms, 25.5%oxygen atoms, 9.5% carbon atoms, 1.5%nitrogen atoms and only 0.5% atoms of otheratoms (Iron, Cobalt, Sodium and Potasiumetc). When we die our atoms will dissembleand move off to form new uses elsewhereas atoms can not be destroyed. Some atomsmay form a part of a flower or other humanbeing or a drop of rain. It is also possiblethat we may be having atoms in our bodywhich once belonged to Budha, Gandhi orNehru.

12. Cloning: Cloning occurs in nature for simple

organisms (bacteria and viruses) which

reproduce by splitting when their DNA has

replicated itself. Cloning can also be done in

humans and other animals when a single

fertiliged egg divides and separates to form

two or more identical individuals. Gene

cloning is generally done in the laboratory by

means of the polymerisation chain reaction

which enables to reproduce millions of

identical gene in short time. In animal cloning,

the donor's DNA is introduced into egg of

another animal of same species after egg's

DNA has been removed. The egg is then

inserted into surrogate animal's womb and

pregnancy procceds as normal. Another

genetic advancement is the creation of

transgenic animals which can be used for the

production of human compatible organs such

as hearts. Pigs are being used for this purpose.

Egg Donor

Egg Donor

Ce ll w ith DNA only

Ce ll m ultip liesproducing an embryo

Ce ll and egg arefused toge ther

Em bryoim p lanted in to

surrogate anima l

Egg w ithou t DNA

Cloning of Animal

Desired gene of DNA (Hum an)

Iden tification Free ing G ene G ene in jection

Creating Transgenic Animal

Fill up the gaps

1. The body is made up of the head, ______and limbs. ((a) arms (b) trunks)

2. The vertebral column is _______axis oftrunk. ((a) central (b) middle)

3. The upper limbs by the sides of the trunk is_______ position ((a) erect (b) anatomical)

4. Sagittal plane is parallel to _______ plane.((a) median (b) lateral)

5. Horizontal plane is also known as ________plane. ((a) median (b) transverse)

6. The adjective medial means ______ to medianplane. ((a) nearer (b) farther)

7. The adjective radial and ulnar can be usedinstead of ______. ((a) medial and lateral(b) lateral and medial)

8. The terms anterior and posterior are usedto indicate _______ of the body respectively.((a) back and front (b) front and back)

9. Nose is _______ to the ears. ((a) anterior(b) posterior)

10. The term palmer and dorsal surfaces ofthe hand. ((a) anterior and posterior (b)posterior and anterior)

11. The arm is ______ to the forearm. ((a) distal(b) proximal)

12. The mouth is _______ to the nose. ((a)superior (b) infevior)

13. If a person is lying, them he is in ________position. ((a) supine (b) prone)

14. Flexion is the _______ of the bones andextension is _______ of the bones. ((a)unfolding, folding (b) folding, unfolding)

15. Flexion and extension of trunk takes placein the ________ plane. ((a) medial (b)lateral)

16. ________ of the limb is the movement awayfrom the midline of the body in the coronal

OBJECTIVE TYPE QUESTIONS

plane while _____ of the limb is themovement towards the body in the coronalplane. ((a) adduction, abduction (b)abduction, adduction)

17. Rotation is a term applied to the movementof a part of the body around its _______axis. ((a) central (b) long)

18. ________ is the movement of the foot sothat the sole faces in medial direction while______ is the opposite movement so thatthe sole faces in a lateral direction. ((a)Eversion, Inversion (b) Inversion, Eversion)

19. Blood is ______ tissue. ((a) Epithelial (b)Connective)

20. ______ tissue has to perform mechanicalfunction. ((a) skeletal (b) fluid connective)

21. All organs of the body are formed of ______.((a) flesh (b) tissue)

22. Tissue is a collection of similar type of_____. ((a) fibres (b) cells)

23. Epithelium is ______ tissue. ((a) covering(b) connecting)

24. Cartilages and bones are _____ tissues. ((a)supporting (b) skeletal)

25. Blood consists of liquid portion (plasma) and______ different kinds of cells. ((a) two(b) three)

26. The haemoglobin is the pigment in ______corpuscles which makes the blood red.((a) erythrocytes (b) leucocytes)

27. Transport of gases (oxygen and carbondioxide) is done by _____ of RBC (Red bloodcorpuscles). ((a) haemoglobin (b) platelets)

28. The haemoglobin combines with oxygen toform oxyhaemoglobin in ______. ((a)lungs(b) tissues)

29. The haemoglobin combines with carbondioxides to form carboxy haemoglobin in_______. ((a) lungs (b) tissues)

ANSWERS

30. The corpuscles which are able to eat bacteriaand other germs so as to defend the bodyagainst disease are ______.((a) RBC (b)WBC

31. The clotting of blood is done by ____. ((a)thrombocyctes (b) leucocytes)

32. Striped muscle tissues are _____ the controlof will. ((a) under (b) not under)

33. The muscles of joints are ______ muscles.((a) striped (b) unstriped)

34. The alimentary canal, the lungs and the bloodvessels have _____ muscles. ((a) unstriped(b) striped)

35. The ______ muscle is found only in the wallof heart. ((a) unstriped (b) cardiac)

36. The study of the parts of the body is ____and the function of the parts is _____. ((a) physiology, anatomy (b) anatomy,physiology)

37. The vascular system is a closed _____system. ((a) hydraulic (b) pressure)

38. The heart works as ____ chambers pump.((a) two (b) four)

39. The heart can be considered as _____ stagespumps. ((a) two (b) four)

40. The respiratory system is a ____ system.((a) air (b) pneumatic)

41. The ______ is the central informationprocessor of the nervous system. ((a) motorunits (b) brain)

42. The _____ is the major organ of theexcretory system. ((a) liver (b) kidney)

43. The filtering of the blood for removal ofwastage is done in ____. ((a) liver (b)kidney)

44. The digestive system includes ____ andassociated glands. ((a) stomach (b)alimentary canal)

45. The digestive pancreatic juice and insulin issecreted by _____. ((a) liver (b) pancreas)

46. Red blood cells are formed in the ______.((a) liver (b) bone marrow)

47. The valves are found in only _____ ((a) artery(b) vein)

48. Artery takes the blood _____ and vein takesthe blood _____ the heart. ((a) away,towards (b) towards, away)

49. A portal system is ______. ((a) vein (b) veinand capillary network)

50. An artery has ______ wall than a vein. ((a)thicker (b) thinner)

1. (b) 2. (a) 3. (b) 4. (a) 5. (b) 6. (a) 7. (b) 8. (b)

9. (a) 10. (a) 11. (b) 12. (b) 13. (a) 14. (b) 15. (b) 16. (b)

17. (b) 18. (b) 19. (b) 20. (a) 21. (b) 22. (b) 23. (a) 24. (b)

25. (b) 26. (a) 27. (a) 28. (a) 29. (b) 30. (b) 31. (a) 32. (a)

33. (a) 34. (a) 35. (b) 36. (b) 37. (a) 38. (b) 39. (a) 40. (b)

41. (b) 42. (b) 43. (b) 44. (b) 45. (b) 46. (b) 47. (b) 48. (a)

49. (b) 50. (a)

Difficult we shall do now, Impossible we shall take afterwards.

INTRODUCTION

1. Physics is the study of nature and law.Nature governs with laws and to explain thelaws, the science of physics is developed.Physics is concerned with the basic ruleswhich are applicable to all objects whetherinnert or living. Therefore understanding ofphysics helps us to apply these laws in thestudy of bio and medical sciences. No onehas been given authority to frame the lawsof physics. These laws were discoveredwhile observing the events happening innature. A falling apple from a tree gaveNewton an idea of law of gravitation.Mathematics has given us a concept ofinduction and deduction reasoning. When aperson makes observations or experimentsand on their basis, reaches a conclusion,then it is said to be inductive reasoning.Deductive reasoning on other hand, proceedsfrom assumptions rather than observations.It is usually by inductive reasoning thatmathematical results are discovered whilethey are proved by deductive reasoning.

1. Mechanics is a science which deals with thestate of rest or the state of motion of bodyunder the action of forces. The applicationof this science to actual problems is calledapplied mechanics. Statics is the branch ofmechanics which relates to bodies at rest.Dynamics is the other branch of mechanicswhich deals with bodies in motion. Theanalysis of force system on bodies is basedon some of basic laws which arefundamental laws of mechanics. First lawof motion states that a body tends to stay instate of rest or of uniform motion unless anexternal force is applied. Second law ofmotion states that the rate of change ofmomentum of a body is directly proportionalto the applied force and in same directioni.e., force = mass acceleration.Third lawof motion states that for every action, thereis an equal and opposite reaction.

2. If all the forces in a system lie in single plane,then it is called a coplanar force system. Ifthe line of action of all forces lie along a

MECHANICS

single line, then it is called a collinear forcesystem. If all forces pass through a singlepoint, it is called a concurrent force system.

3. Moment of a force about a point is themeasure of its rotational effect. It is theproduct of the magnitude of the force andthe perpendicular distance of the point fromthe line of action of the force. The pointfrom where the moment taken is calledmoment centre and the perpendiculardistance of the point from the line of actionof the force is called moment arm

4. Forces on a body can be applied forces andnon applied forces. Non applied forces areself weight and reactions. Self weight alwaysact vertically downward and it is equal tothe product of mass and gravitationalacceleration. Reactions are self adjustingforces developed by other bodies or surfaceswhich are equal and opposite to forces(actions) exerted by the body. For smoothcontact, the direction of reaction is normalto the surface of contact.

5. Free body diagram of a body is a diagram inwhich the body under consideration is freedfrom all the contact surfaces with reactionforces and diagram of the body is shownwith applied forces and reaction forces atpoints where body was making contact withother surfaces. Reaction at joints andmuscles forces are worked out by drawingfree body diagrams.

T = T en sio n R = R e ac tio n m g = w eigh t

F re e B o dy

D ia gra m

T

R

m g

6. A body is said to be in equilibrium under asystem of coplanar forces if Px = 0 andPy = 0. The resultant of coplanarconcurrent forces not in equilibrium is given

by

R = 2 2( ) ( )px py + and angle of inclination is given by tan1

y

x

P

P

where px and Py are sum of resolved

forces in x and y directions.7. A body is said to be in equilibrium under

coplanar force system if Px = 0,Py = 0 and M = 0. Hence we see that thecondition of equilibrium gives threeequations to find only three unknowns. Asystem of forces is determinate incase it hasthree unknowns only, otherwise it isindeterminate. Lami's theorem of equilibrumcan be applied for three concurrent forces.According to it, the forces are proportionalto sine of the angle between other twoforces.

Hence, 1

23sin

p

=2

13sin

p

= 3

12sin

p

P 3 P 2

P 1

13

23

12

8. Friction : When a body moves or tends tomove over another body, a force opposingthe motion is developed at contact surface.Friction force = coefficient friction force isalways less than static friction. Friction canbe reduced by lubricating the contactingsurface. Dry surface friction is alwaysgreater than wet surface friction. Frictioncan always be reduced if contact betweenthe surfaces can be avoided by keeping alayer of liquid in between the surfaces.Synovial joints in our body work on sameprinciple.

!

x

+y

a 1a2

y1 y2

o +x

+y

oo

+y

x

y

x oa1 1x oa2 2

x o

9. Bending and torsonal stresses: Thebending equation is applicable where shear

force is zero and it is given by M

I=

E

R= y

where M = applied moment, I = moment ofinertia, R = radius and curvature, =bending stress, E = Young's modulus and y= layer from centre where bending stress isbeing analysed. Moment of inertia is nothingbut second moment of area or mass.Moment of inertia of a lamina is

(a) Moment of inertia about x x

=Ix = a1 y2

1 + a2 y22 ..... = ay2

(b) Moment of inertia about y y

= Iy = a1x12 + a2x

22 .... = ax2

(c) Moment of inertia of circular section =

Ixx = Iyy =4

64

D

(d) Moment of inertia of hollow circularsection

= Ixx = Iyy = 64

(D4 d4)

Similarly for pure torsion we can apply

p

T

I =

r

=

G

l

where T = Torque, Ip = polar

moment of inertia, = shear stress r = radius, G =rigidity modulus, l = length and = angle of twist.

10. Centre of gravity: The entire mass of abody is assumed to be concentrated at apoint and the force of gravity acts at thispoint which is called the centre of gravity.The centre of gravity of a body is located ata point about which sum of moments ofweights of all its particles is zero. Hence ifthe body is supported at its centre of gravity,the body will remain in rotational equilibriumas the moment of weight of all its particlesabout the point of support will be zero.

y1

y2

ox

y3

x1x2 x3

m 1

m 2

m 3

y

m 1

m 2g

m cg

g CG (Total weigh t=m g + m g + m g)1 2 3

xcg

ycg

Centre of Gravity of Particles

Consider a body with three particles only withmasses as m1 m2 and m3. The moment of threeparticles at point '0' about y y axis is equal to m1gx1 + m2 g x2 + m3 g x3. Total mass of the body atcentre of gravity (CG) is m1 + m2 + m3 and momentof inertia is equal to (m1 + m2 + m3) g xcg.

Hence, xcg =1 1 2 2 3 3

1 2 3

m x m x m x

m m m

+ ++ +

= i i

i

m x

m

and ycg = i i

i

m y

m . There is another method to find

the centre of gravity by actually balancing the body

on a knife edge in three planes i.e., median plane,coronal plane and horizontal plane. The point ofbalance will give the line in that plane on which thecentre of gravity of the body is lying.The intersection of these three lines will give theactual centre of gravity of the body from a point inspace. Statistical method can also be used for finding

Horizontal Plane

y

Median Plane

x

z

Coronal plane

the centre of gravity. A man (weight = wm) is lyingsupine on a board (weight = wb) and reaction forceRA and RB are read from the measuring scale. Thelength of board is 'l' and its weight will act at l/2

while weight of the man acts at xcg from point A.The free body diagram of the body is shown in thefigure. Now Py = 0, therefore RA + RB = wm+ wband wm can be found out. Similarly MA = 0,therefore,

2

l wb + xcg wm l RB = 0, and xcg

can be found out. Similarly ycg and zcg canbe found out.

A B

Board we ight wb

we ighing sca le

W eigh ing sca le

W eigh t o f m an = w m

Aw m

R A w b

B

R B

xCG

l/2

l11. The centre of gravity of a man depends on

the relative position of his limbs (lower andupper) as compared to the anatomicalposition. Locations of the centre of gravityof upper and lower limbs will changedepending upon their positions which willchange the overall centre of gravity of theman. If knee is flexed backwards, the centreof gravity of leg as well as that of the manwill shift backwards. Smilarly, the centre ofgravity of arm as well as the man shiftsforward if the elbow is flexed. An athleticcan take full advantage by positioning hislimbs so as to shift his centre of gravity ashigh as possible while jumping over the highbar.

Positioning of Limbs toHelp While Jumping

!

1. Viscosity : It is defined as the property of afluid which determines its resistance toshearing stresses. It is a measure of internalfluid friction which exerts resistance to flow,It is primarily due to cohesion and molecularmomentum exchange between fluid layerswhich appears as shearing stresses betweenthe moving layers of the fluid when the flowtakes place. An ideal fluid one which has noviscosity. But no fluid is exists which canbe classified as an ideal fluid having zeroviscosity. However fluids with very smallviscosity can be considered as ideal fluids.In the figure, a fluid flow is shown on asolid boundary when two layers are 'dy' apartand moving one over the other with differentvelocities, say 'u' and 'u + du'. The top layercauses a shear stress on the adjacent lowerlayer and this lower layer also cause a shearstress on the layer lower to it and this goeson. According to Newton's law of viscosity,the shear strees () on a fluid element layeris directly proportion to the rate of shear

strain or the rate of change of velocity du

dy

.

dy

y

u

u + du

dudy

= dudy

=dynamic viscosity

Solid Boundary

or = ( )/du dy

= stress

strainThe viscosity can be defined as shear stress requiredto produce unit rate of shear strain. The unit ofviscosity

= 2Force Time

(length)

= 2Newton Second

(meter)

and one poise = 1/10 Ns/m2. Kinematic viscosity isdefined as the ratio between the dynamic viscosityand density of the fluid.

Hence, v =Viscosity

density =

and it has unit = 2(metre)

second=

2m

s.

One stoke =1042m

s. The fluids which

follow Newton's law of viscosity are knownas Newtonian fluid. Hence fluids can beclassified as :

(a) Newtonian fluids : These fluids followNewton's viscosity equation. For suchfluids, does not change with rate ofdeformation. Water, kerosene and airare Newtonian fluids.

(b) Non Newtonian fluids : Fluids whichdo not follow the linear relationshipbetween shear stress and rate ofdeformation are termed as nonNewtonian fluids. Solutions,suspensions (slurries), mud flows,polymer solutions and blood areexamples of non Newtonian fluids.These fluids are generally complexmixture and they are studied underrheology (a science of deformation andflow).

(c) Plastic fluid : Non Newtonian fluid inwhich initial yield stress is to be exceededto cause a continuous deformation.

FLUID MECHANICS

PREFIXES

(d) Ideal fluid : Fluid is incompressible andhas zero viscosity. Stress is zeroregardless of motion of the fluid.

2. Boundary layer: When a real fluid flowspast a solid boundary, the fluid particlesadhere to the boundary and the condition ofno slip occurs. It means that the velocity offluid close to the boundary will be same asthat of the boundary. In case the boundaryis stationary, the fluid velocity at theboundary will be zero. As we move furtheraway from the boundary, the velocity of thefluid will be higher. Due to variation ofvelocity as we move away from theboundary, a velocity gradient (du/dy) willexist. The velocity of the fluid increasesfrom zero velocity on the stationaryboundary to free stream velocity (u) of thefluid in the direction normal to the boundary(y). The theory dealing with boundary layerflow is called boundary layer theory.

Flow Solid B oundary

Boundary Layer

According to this, the flow in theneighbourhood of the solid boundary maybe divided into two regions :

(a) A very thin layer of fluid called theboundary layer is in the immediateneighbourhood of the solid boundarywhere the variation of velocity existsfrom zero at solid boundary to freestream velocity in the direction normalto the boundary. In this region, avelocity gradient = du/dy exists andhence the fluid exerts a shear stress onthe boundary in the direction of flow. (shear stress) = du/dy where =

viscosity.

(b) The velocity of the fluid outside theboundary layer is constant and equal tothe free stream velocity. There is novelocity gradient in this region andhence shear stress is also zero in thisregion.

3. Flow in tube: When a fluid enters a tube/pipe from a large reservoir where thevelocity is uniform and parallel to the axisof the tube (as shown in the figure), thevelocity profile is a flat surface at the entry.Immediately on entry, the fluid velocity invicinity of the surface of the tube is affectedby friction force. However, the velocityprofile far from the surface and near the axisof the tube remains still flat (same as freeflow). As the fluid moves further in the tube,flat portion decreases and some distanceafter, a paraboloidal velocity profile for thefully developed flow is reached. The flowat the inlet and flow beyond point A (regionIII) is called fully developed flow.

I

II

I

III

A

The entry length is defined as the length inwhich 99% of the free flow velocity isattained. The flow in the entry length portionconsists of two parts:

(1) the flow in region I near the tube sur-face is called boundary layer flow.

(2) the flow in the region II is called coreflow (plug flow)

4. Laminar and turbulent flow: The particlesmove in curved unmixing layers or streamsand follow a smooth continuous path in thelaminar flow. The paths of fluid movementare well defined and the fluid particles retain

Boundary Layer

Flow Tube and Entry Length

!

their relative positions at successive crosssections of the flow passage in the laminarflow. There is no transverse displacementof fluid particles. Soldiers marching inorderly manner is an analogy to laminar flow.In turbulent flow, the motion of fluidparticles is irregular. The fluid particles movealong erratic and unpredictable paths. Thevelocity of fluid particle fluctuates bothalong the direction of flow and alsoperpendicular to the flow. A crowd ofcommuters on a railway station rushing forboarding a train is an analogy.

The Reynolds numbers is a dimensionlessnumber which is used to predict whetherthe flow is laminar or turbulent in a tube.The Reynold's number = Inertial force/viscous force = u2D2/ uD = uD/ =uDv, where = viscosity, v = kinematicviscosity = /, = density, u = velocityand D = diameter of tube. If inertia force ismuch higher than viscous force, Reynoldsnumber will be more and less chance forthe flow to be laminar. In a tube, turbulentflow occurs when Reynolds number > 6000.For laminar flow in a tube, following areapplicable:

(a) Strear stress = Px

. 2

r where r =

radius of layer and P

x

= Pressure gra-

dient along direction of flow.

(b) Velocity u = 1

4

P

x

(R2 r2) where

R = radius of tube, r = radius of layer

(c) Ratio of maximum velocity to averagevelocity = 2

(c) Loss of pressure head = 232 u L

g Dwhere u =

Flow

Area and L = Length of

flow.

5. The tube must have same thickness of the

wall depending upon the pressure of the

fluid. Thickness (t) = p

Pr

where P =

pressure, r = radius and p = permissiblestress

Radius = r

Th ickness = t

Pressure (p)

6. Equation of continuity and Bernaulli'sequation. The total mass of fluid goinginside the tube through any cross sectionremains same. Therefore the equation ofcontinuity is A1u1 = A2 u2, where A standsfor cross sectional area and u stands forvelocity. As per Bernaulli's equation, the totalhead of the fluid remains constant at everycross section of the tube. The Bernoulli'sequation is

P + 1

2 u2 + gh = constant where

P = pressure, = density, g = coefficient ofgravity, h = height of cross section from adatum line and u = velocity of the fluid.

7. Applications of Bernaulli's equation. Thespeed of liquid coming out through a hole ina tank at a depth 'h' below the free surfaceis the same as that of a particle falling freelythrough the height 'h' under gravity i.e., u =

2gh . This is known as Torricelli's

theorem. When a person is bleeding, we tryto reduce 'h' so that blood flow can bereduced. Other application is Aspirator pumpwhich works on the principle that thepressure of fluid decreases where ever itsspeed increases. As shown in the figure, theair is pushed through a narrow opening at

Thin Tube

'A' resulting in drop of pressure. The liquidin the bowl is raised by the pressure dropand liquid is sprayed with the expelled air. Acricket ball having a shining side and rougha side on the left and right as shown in thefigure will deviate towards the shining sideas air passing over the shining side will faceless resistance and gain more speed resultingin lower pressure as compared to the roughside. Similarly, an aerofoil has longerdistance at the top surface as compared tothe bottom surface which makes the airmove at higher speed at the top surface ascompared to the bottom surface resulting inlower pressure at top the surface and higherpressure at the bottom surface whichprovides a lift to the aerofoil. A venturi tubeis used to measure the flow of speed of afluid in a tube. The tube has a constriction(throat) which makes the fluid flow at higherspeed resulting in drop of pressure at throat.The pressure P1 P2 = g (h1 h2) asshown in the figure. Alsov2

2 v12 = 2g(h1 h2) where v1 and v2 are

velocities. Knowing A1and A2 (areas), therate of flow of liquid past a cross-sectioncan be found out.

u

h

u = 2gh

Deviation

Sh in ing Rough

v1 v2

v > v1 2

Cricket ball

A Liqu id spray

bow l

Venturi Tube

Constriction

P 1v1h 1

P 2v2h 2

h h1 2

v1

L ift

v > v1 2

v2

8. Pascal's law : If the pressure in a liquid ischanged at particular point, the change istransmitted to the entire liquid without beingdiminished in magnitude. Pascal's law hasseveral applications like hydraulic lift andreaction force at the joints of our body asshown in the figure.

F

A 1

W

A 2

P A = F1 1P A = W1 2

P = P RESSURE CO NSTANT1

Area A >> A 2 1 W >> F

Torricell's Theorem

Aspirator Pump

Aerofoil

Hydraulic Lift

!

Reaction Force at Joint

Reaction R is always vertical due to

uniform flu id p ressure

FB D

Fluid

R

9. Gauge pressure : The standard atmosphericpresure is defined as the pressure producedby a column of mercury of 760 mm high.Hence Patm = gh = (13.6 103) 9.8 760

1000 = 1.01 105 pascal = 1.01 bar.

Pressure of the vessel can be higher or lowerthan atmospheric pressure. Pressure ismeasured by a manometer. Manometer is aU-tube with one end opens to atmosphereand other is connected to vessel.

P abe

P atm

hg h v

P = P + G auge P r

= P + h g W here h = he ight

abs

g

atm

atm HG gP = P Vacuum Pr

= P h g where h = vacuum heigh t

abs

v

atm

atm HG v

P abs

P atm

If pressure in vessel (Pabs) is lower thanPatm, mercury is forced into the limbconnected to vessel. Higher thanatmospheric pressure is known as gaugepressure while lower pressure thanatmospheric pressure is called vacuumpressure. The flow in cardiovascular systemis higher than atmospheric pressure and flowat various places is given by gauge pressureonly. The blood pressure of a healthy personis 120/80mm Hg (gauge pressure) duringsystole/diastole.

1. Temperature is an intensive property of asystem (intensive property does not dependupon mass) and indicates relative hotnessor coldness from the reference states.Boiling point and freezing point of waterare acceptable reference states.Thermometer is a temperaturemeasurement system which can show somechange in its characteristics (termed asthermometric property) due to heatinteraction taking place with the body whosetemperature is being measured.Temperature is measured either incentrigrade or fahrenheit for human body.The relation between these two

thermometers is 100

cT = 32

180fT

where Tc =

temperature in centrigrade, and Tf =temperature in fahrenheit. Boththeromometers are mercury scalethermometers in which length of mercurycolumn is proportion a to temperature ofthe body. The normal oral (mouth)temperature of a healthy person is about37C or 98.6F. The underarm temperatureis one degree lower, whereas the rectaltemperature is one degree higher than thatof oral temperature. The temperaure ofbody is controlled by the body so that itremains constant as 37C. However duringfever, the temperature of body increasesas temperature control mechanism fails,thus causing additional metabolism becausehigher temperature inside the bodyaccelerates the chemical reactions. Duringfever, shivering takes place as the blooddoes not flow to skin and muscle tissueswhich is essential to keep them warm.When body temperature falls to normaltemperature, increased sweating takesplace as additional heat is eliminated.

TEMPERATURE

Fill up the gaps1. Static is the branch of mechanics which

relates to bodies in _____. ((a) rest (b)motion)

2. If all the forces in a system lie in single plane,then it is called a ____ force system. ((a)coplanar (b) concurrent)

3. If all the forces in a system pass through apoint it is called a _____ force system. ((a)coplanar (b) concurrent)

4. Lami's theorem can be applied for three_____ force system. ((a) coplanar (b)concurrent)

5. The condition of equilibrium in a coplanarforce system gives ____ equations. ((a)Three (b) two)

6. The fluids which follows T = du/dy arecalled _____ fluids. ((a) Ideal (b)Nowtonian)

7. Blood is a _____ fluid. ((a) Newtonian (b)non Newtonian)

OBJECTIVE TYPE QUESTIONS

8. Ideal fluid has _______ viscosity. ((a) unit(b) zero)

9. The ratio of Inertia force and viscous forceis ______ number. ((a) Rayleigh (b)Reynold)

10. Turbulent flow has _____ value of Reynoldnumber. ((a) lower (b) higher)

11. The _____ is used for measuring gauge orvacuum pressure. ((a) manometer (b)pressure meter)

12. The blood pressure is always given in _____.((a) gauge height (b) vacuum height)

13. P + u2 + gh = constant is known as______ equation. ((a) hydraulic (b) Bernoulli)

14. A1u1 = A1 u2 wher A = area and u = velocityis known as ______equation. ((a) continuity(b) constant)

15.M

I =

E

R = y

is called _____equation. ((a)

Bending moment (b) Torsion)

ANSWERS

1. (a) 2. (a) 3. (b) 4. (b) 5. (a)6. (b) 7. (b) 8. (b) 9. (b) 10. (b)11. (a) 12. (a) 13. (b) 14. (a) 15. (a)

1. Prefix bio denotes something connectedwith life. When basic science of physics andchemistry have been applied to living things,this intermarriage has been named asbiophysics and biochemistry. Hence,marriage of discipline of medicine andengineering is called biomedical engineering.The aim of biomedical engineering is theapplication of the methodology andtechnology of physical sciences andengineering to the problem of the livingsystems with emphasis on diagnosis,treatment and prevention of diseases in man.

2. Access to adequate health care is comparableto the fundamental rights of a human being.The view has led to the development of largeand sophisticated health care systems. Thecomponents of health care include preventivemedicine, diagnosis, therapy andrehabilitation. The critical element in thischain is diagnosis. Once a physician makesa diagnosis and institutes therapy, diagnosticprocedures are used then to monitor therapyand to assess its adequacy to maintain ormodify the therapy. High technology medicalequipments are being introduced in healthcare industry as this industry is growing at

fast rate. High technology equipmentsnormally require more skills. To control thecorrect functioning of these equipments, onehas to understand its basic operatingprinciples and be able to apply someperformance assurance tests for thatpurpose. The physicians utilizing the resultsproduced with these equipments need tounderstand the limitation of the technology.Hence physicians and biomedical engineerscan not work in isolation.

1. Science and technology are evolving rapidly.This creates the potential for applying theseinnovations also to health care products.Improved and cheaper version of old medicalequipment and new equipment have beenemerging as a consequence of this. Advancedmedical equipment mean innovativeproducts which may be technologicallysimple or complicated. Examples of theseinclude :

(a) Artificial organs, such as heart valves,hip joints and implanted pacemakers.More research in medical science toensure reliability and durability.

Good things come to those who wait, but better things come to those who try.

INTRODUCTION

ADVANCED MEDICAL EQUIPMENT ANDSYSTEMS

(b) Patient-monitoring equipment which usesophisticated transducers together withmicroelectronics, microprocessor andsoftware for processing the measuredsignals.

(c) Information system for patient datamanagement and for decision supportintegrating various sources of patientdata and incorporating knowledgebased techniques (artificial intelligence,expert system) for the interpretation ofthe compiled data.

(d) Imaging of the anatomy and functionsof the human body. The technology forobtaining and storing the images ischanging from film to digital integra-tion of the various image sources withpicture archiving and communicatingsystem (PACs) and image processingstations is the present practice.

(e) Automated laboratory equipment for theprocessing of patient samples (blood,urine etc). It has cut down the cost bymaking tests simpler, accurate andfaster. Information systems areextensively used to manage the process,for quality control and for producinglaboratory reports, for archiving or fordisplay to treating physicians.

(f) Technical aids for the handicapped (andfor the elderly) comprising both simpleand complex devices. Development ininformation technology and in robotics,have opened up new possibilities toprovide technical aids to thehandicapped both at home and at work.(More on robotic refer chapter1)

1. The effective utilization of high technologyequipment and systems necessitates thetechnical expertise of clinical engineers,hospital physicists and computer scientists.

The efficient and cost effective utilizationof a new technology also requires carefulplanning in organisation and ways ofoperation. Any new equipment introducedwould require engineers to operate and tomaintain it. Regular service and regularpreventive maintenance combined withperformance assurance procedure is morecost effective. The installation of newequipment can be expensive in terms of bothactual purchasing and installation costs; andadditional technical staff requirements tooperate and maintain.

1. As name suggests, biomedical engineeringis interaction of medicine and engineeringHence biomedical engineering can be definedas application of the knowledge gained by across fertilization of engineering and thebiological sciences so that both will be morefully utilized for the benefit of man.

1. The field of biomedical engineering is everexpanding as new engineering applicationsin medical field are emerging. A tendencyhas been seen to describe the personnelworking in different speciality areas of bioengineering with the name of the area. Atendency has arisen to call the biomedicalengineer as person working in the interfacearea of medicine and engineering whereasthe practitioner working with physician andpatient is called a clinical engineer. Similarlytitles of hospital engineer, medical engineer,bioinstrumentation engineer, biomaterialengineer and rehabilitation engineer are beingused depending upon personnel working indifferent speciality areas of biomedicalengineering. Speciality areas are :(a) B i o i n s t r u m e n t a t i o n : I t i m p l i e s

measurements of biological variableswhich help the physicians in diagnosing

BIOMEDICAL ENGINEERING

SPECIALITY AREA OF BIOMEDICALENGINEERING

REQUIREMENT FOR ADVANCEDMEDICAL EQUIPMENT

and treatment. For the measurement ofbiological variables, applications ofelectronics and measurement techniquesnecessitate understanding andknowledge to operate the devices. Inorder to handle data, computers areessential part of bioinstrumentation.Large amount of information in medicalimaging system can be processed by acomputer.

(b) Clinical engineering: It is application ofengineering knowledge to health care inhospitals.Clinical engineer withphysician, nurses and other staff form ahealth care team so that health carefacilities (patient monitoring equipment,diagnosing equipment, technical aidsfor the handicapped) can be effectivelyutilised and computer data base can bemaintained.

(c) Biomaterial engineering: Bomaterialsinclude both living tissues and artificialdeveloped materials which are suitablefor implantation. Materials can be metalalloys, ceramics and polymers whichmust be chemically inert, stable andmechanically strong to withstand therepeated forces for a lifetime.

(d) Cellular, tissue and genetics engineering:With advancement in biomedical field, itis possible to tackle the biomedicalproblems at microscopic and nenoscopiclevel. The anatomy biochemistry andmechanics of cellular and subcellularstructure are studied to understanddisease process and to find out suitabletherapy to overcome malfunctioning.

(e) Medical imaging engineering: There aremany techniques to generate the imageof organs inside the body. Various raysand radiations like ultrasound, X-rays andnuclear radiation with physicalphenomenons like magnetism, sound,fluorescence and reactions onphotographic film, can be used togenerate or display internal image of thebody. These images can be digitized so

that data can be handled by the computer.(f) Rehabilitation engineering: Rehabilita-

tion relates to both handicapped andelderly persons. Rehabilitation engineer-ing aims to enhance the capabilities andto improve the quality of life of per-sonnel having physical and cognitiveimpairment. The development of pros-thesis for amputees, provision of properwheel chair to paraplegic which per-mits regular exercise for fitness so thatregular assessment of the functionalcapacity can be made and assistive de-vices for elderly persons are some ofthe contributions of rehabilitationengineering.

(g) Orthopadic biochemistry: It is the fieldin which malfunctioning of bones,muscles and joints is studied so thatartificial joints for replacement can bedesigned.

(b) System physiology: It is the field in whichengineering techniques and tools are usedto gather a comprehensive understandingof the function of living organismsranging from bacteria to human body.Computer is used to model physiologicalsystems for analysis and understanding.

2. Biomedical engineer is a professional whohas expertise both in biological sciences andengineering field so as to effectively andsafely manage medical devices andinstruments, for an overall enhancement ofhealth care. He can use engineeringexpertise to analyse and solve problems inbiology and medicine providing an overallimprovement of health care. Otherdefinitions by various committes are :

(a) A clinical engineer is a professional whobrings to health care facilities a level ofeducation, experience and accomplish-ment which will enable him toresponsibly, effectively and safelymanage and interface with medicaldevices, instruments and systems and

the use of these for patient care,because of high level of competenceand responsibly. He can directly servethe patient, physician, nurse, and otherhealth care professionals to use of themedical instrumentations.

(b) Biomedical engineer is a person workingin research or development in theinterface area of medicine andengineering whereas the practitionerworking with physician and patient iscalled a clinical engineer.

(c) Biomedical engineer is a professionalwho applies knowledge gained by across fertilization of engineering and thebiological sciences so that both will bemore fully utilized for the benefit of man.

(d) A biomedical equipment technician is anindividual who is knowledgeable aboutthe theory of operation, the underlyingphysiologic principles, and the practical,safe clinical applicaton of biomedicalequipment. His capabilities may includeinstallation, calibration, inspection,preventive maintenance and repair ofgeneral biomedical and related technicalequipment as well as operation orsupervision of equipment control, safetyand maintenance programmes andsystems.

3. With the need of sophisticated health caresystem and advent of advanced medicalequipment, there is a growing demand ofbiomedical engineers. There is a growingdemand for them in these places:

(a) In hospital as clinical engineer

(b) In industry involving manufacturingbiomedical equipment

(c) In research facilities of educationalmedical institutions.

(d) In government regulatory system forproduct testing and safety

(e) In performance testing of a newproduct or existing product in hospital

(f) In establishing safe standards fordevices

(g) In managerial position as technicaladvisor in marketing department

(h) In creating design to understand livingsystem and technology

(j) In coordinating and interfacing functionusing background in engineering as wellas medical field

(k) In university and in teaching institutions.Biomedical engineers can effectivelysupervise laboratories and equipment inresearch institutions

OBJECTIVE TYPE QUESTIONS

Fill up the gaps1. Access to adequate health care is comparable

to the ________ right (a) fundamental (b)human

2. High _________ medical equipment arebeing introduced in health care industry (a)finish (b) technology

3. Proper working of the equipment is indicated

by performance ______ tests (a) assurance(b) quality

4. Marriage of discipline of medicine andengineering is called _________ (a) medicalengineering (b) biomedical engineering

5. Bioinstrumentation measures ______variable (a) physical (b) biological

6. Biomaterial are used for _________(a) implantation (b) instruments

7. Preventive medicine, diagnosis, therapy andrehabilitation are the components of________ (a) medicine (b) health care

8. High technology equipments normallyrequire more _________ (a) skill (b) men

9. Physicians an