Biomedical Engineering. Биомедицинская инженерия. Учебное пособие

assumed to be an incompressible Newtonian fluid. However, this assumption fails when considering forward flow within arterioles. At the microscopic scale, the effects of individual red blood cells become significant, and whole blood can no longer be modeled as a continuum. When the diameter of the blood vessel is just slightly larger than the diameter of the red blood cell there is a decrease in wall shear stress. However, as the diameter of the blood vessel decreases further, the red blood cells have to squeeze through the vessel and often can only pass in a single file. In this case, the wall shear stress increases. An example of a gaseous biofluids problem is that of human respiration. Recently, respiratory systems in insects have been studied for bioinspiration for designing improved microfluidic devices.

b) ______ is the study of friction, wear and lubrication of biological systems especially human joints such as hips and knees. In general, these processes are studied in the context of Contact mechanics and tribology. Its additional aspects include analysis of subsurface damage resulting from two surfaces coming in contact during motion, i.e. rubbing against each other, such as in the evaluation of tissue-engineered cartilage.

с) ________ is the application of biomechanics to non-human organisms, whether used to gain greater insights into humans (as in physical anthropology) or into the functions, ecology and adaptations of the organisms themselves. Common areas of investigation are Animal locomotion and feeding, as these have strong connections to the organism's fitness and impose high mechanical demands. Animal locomotion has many manifestations, including running, jumping and flying. Locomotion requires energy to overcome friction, drag, inertia, and gravity, though which factor predominates varies with environment.

This branch overlaps with many other fields, including ecology, neurobiology, developmental biology, ethology, and paleontology. Comparative biomechanics is often applied in medicine as well as in biomimetics, which looks to nature for solutions to engineering problems.

d) _____ is the application of engineering computational tools to study the mechanics of biological systems. Computational models and simulations are used to predict the relationship between parameters that are otherwise challenging to test experimentally, or used to design more relevant experiments reducing the time and costs. Mechanical modeling using finite element analysis has been used to interpret the experimental observation of plant cell growth to understand how they differentiate, for instance. In medicine, over the past decade, the Finite element method has become an estab-

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lished alternative to in vivo surgical assessment. One of the main advantages of this field lies in its ability to determine the endo-anatomical response of an anatomy, without being subject to ethical restrictions. This has led FE modeling to the point of becoming ubiquitous in several fields of Biomechanics while several projects have even adopted an open source philosophy (e.g. BioSpine).

e)The mechanical analysis of biomaterials and biofluids is usually carried forth with the concepts of _______. This assumption breaks down when the length scales of interest approach the order of the micro structural details of the material. One of the most remarkable characteristic of biomaterials is their hierarchical structure. In other words, the mechanical characteristics of these materials rely on physical phenomena occurring in multiple levels, from the molecular all the way up to the tissue and organ levels.

Biomaterials are classified in two groups, hard and soft tissues. Mechanical deformation of hard tissues (like wood, shell and bone) may be analysed with the theory of linear elasticity. On the other hand, soft tissues (like skin, tendon, muscle and cartilage) usually undergo large deformations and thus their analysis rely on the finite strain theory and computer simulations. The interest in continuum biomechanics is spurred by the need for realism in the development of medical simulation.

f)The application of biomechanical principles to plants, plant organs and cells has developed into the subfield of ________. Application of biomechanics for plants ranges from studying the resilience of crops to environmental stress to development and morphogenesis at cell and tissue scale, overlapping with mechanobiology.

g)In ______, the laws of mechanics are applied to human movement in order to gain a greater understanding of athletic performance and to reduce sport injuries as well. It focuses on the application of the scientific principles of mechanical physics to understand movements of action of human bodies and sports implements such as cricket bat, hockey stick and javelin, etc. Elements of mechanical engineering (e.g., strain gauges), electrical engineering (e.g., digital filtering), computer science (e.g., numerical methods), gait analysis (e.g., force platforms), and clinical neurophysiology (e.g., surface EMG) are common methods used in sports biomechanics.

This branch can be stated as the muscular, joint and skeletal actions of the body during the execution of a given task, skill and/or technique. Proper understanding of biomechanics relating to sports skill has the greatest impli-

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cations on: sport's performance, rehabilitation and injury prevention, along with sport mastery.

More and more scientists took to learning about the human body and its functions. There are not many notable scientists from the 19th or 20th century in bio-mechanics because the field is far too vast now to attribute one thing to one person. However, the field is continuing to grow every year and continues to make advances in discovering more about the human body.

1.8. Answer the questions:

1.What problems are there with liquid biofluids?

2.Why is it important to study human joints?

3.What is biomimetic?

4.What examples of animals’ characteristics useful in technology can you give?

5.Which branch deals with athletic performance?

6.What groups can biomaterials be classified into?

7.Why is it important to apply of biomechanical principles to plants?

8.What tissues can be found in human body?

9.What are computational models and simulations used for?

10.What is biotribology?

1.9.Find the Gerund, the Infinitive and the Participle forms in the texts above. State the forms and functions.

1.10.Write a summary of the text.

1.11 Make a presentation about one of the fields of biotechnology.

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2.2. Make all possible word combinations:

2.3.Write 10 sentences with these word combinations.

2.4.Answer the questions: What medical devices do you know? What are they used for?

2.5.Scan the text and check your answers.

2.6.Read and translate the text:

Types of Medical Devices

A medical device is intended for use in the diagnosis of disease or other conditions in the cure, mitigation, treatment, or prevention of disease. Some examples include pacemakers, infusion pumps, the heart-lung machine, dialysis machines, artificial organs, implants, artificial limbs, corrective lenses, cochlear implants, ocular prosthetics, facial prosthetics, somato prosthetics, and dental implants. Stereolithography is a practical example of medical modeling being used to create physical objects. Beyond modeling organs and the human body, emerging engineering techniques are also currently used in the research and development of new devices for innovative therapies, treatments, patient monitoring, of complex diseases.

Medical devices are regulated and classified as follows: Class I devices present minimal potential for harm to the user and are often simpler in de-

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sign than Class II or Class III devices. Devices in this category include tongue depressors, bedpans, elastic bandages, examination gloves, and hand-held surgical instruments, and other similar types of common equipment.

Class II devices are subject to special controls in addition to the general controls of Class I devices. Special controls may include special labeling requirements, mandatory performance standards, and postmarket surveillance. Devices in this class are typically non-invasive and include X-ray machines, PACS, powered wheelchairs, infusion pumps, and surgical drapes.

Class III devices generally require premarket approval or premarket notification, a scientific review to ensure the device's safety and effectiveness, in addition to the general controls of Class I. Examples include replacement heart valves, hip and knee joint implants, silicone gel-filled breast implants, implanted cerebellar stimulators, implantable pacemaker pulse generators and endosseous (intra-bone) implants.

Medical/biomedical imaging is a major segment of medical devices. This area deals with enabling clinicians to directly or indirectly "view" things not visible in plain sight (such as due to their size, and/or location). This can involve utilizing ultrasound, magnetism, UV, radiology, and other means.

An MRI scan of a human head, an example of a biomedical engineering application of electrical engineering to diagnostic imaging. Click here to view an animated sequence of slices. Imaging technologies are often essential to medical diagnosis, and are typically the most complex equipment found in a hospital including: fluoroscopy, magnetic resonance imaging (MRI), nuclear medicine, positron emission tomography (PET), PET-CT scans, projection radiography such as X-rays and CT scans, tomography, ultrasound, optical microscopy, and electron microscopy.

An implant is a kind of medical device made to replace and act as a missing biological structure (as compared with a transplant, which indicates transplanted biomedical tissue). The surface of implants that contact the body might be made of a biomedical material such as titanium, silicone or apatite depending on what is the most functional. In some cases, implants contain electronics, e.g. artificial pacemakers and cochlear implants. Some implants are bioactive, such as subcutaneous drug delivery devices in the form of implantable pills or drug-eluting stents.

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Bionics. Artificial body part replacements are one of the many applications of bionics. Concerned with the intricate and thorough study of the properties and function of human body systems, bionics may be applied to solve some engineering problems. Careful study of the different functions and processes of the eyes, ears, and other organs paved the way for improved cameras, television, radio transmitters and receivers, and many other tools.

Biomedical sensors. In recent years biomedical sensors based in microwave technology have gained more attention. Different sensors can be manufactured for specific uses in both diagnosing and monitoring disease conditions, for example microwave sensors can be used as a complementary technique to X-ray to monitor lower extremity trauma. The sensor monitor the dielectric properties and can thus notice change in tissue (bone, muscle, fat etc.) under the skin so when measuring at different times during the healing process the response from the sensor will change as the trauma heals.

2.7. Answer the questions:

1.What is a medical device?

2.What classes of medical devices are there?

3.Why are the classes different?

4.What is bionics?

5.What is the role of biomedical sensors?

6.What is an implant?

7.What does MRI stand for?

8.What materials are used for implants?

9.Why are implants made of these materials?

10.What can a missing body part be replaced with?

2.8.Find the Gerund, the Infinitive and the Participle forms in the texts above. State the forms and functions.

2.9.Write a summary of the text.

2.10.Choose one type of medical devices and make a report. Present it to the class.

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Unit 3. Rehabilitation Engineering

3.2. Make all possible word combinations:

3.3.Write 10 sentences with these word combinations.

3.4.Answer the question: What is rehabilitation engineering? What engineering branches is it connected to?

Scan the text and check your answer. 3.5. Read and translate the text:

What is Rehabilitation Engineering

Rehabilitation engineering is the systematic application of engineering sciences to design, develop, adapt, test, evaluate, apply, and distribute tech-

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nological solutions to problems confronted by individuals with disabilities. Functional areas addressed through rehabilitation engineering may include mobility, communications, hearing, vision, and cognition, and activities associated with employment, independent living, education, and integration into the community.

While some rehabilitation engineers have Master's degrees in rehabilitation engineering, usually a subspecialty of biomedical engineering, most rehabilitation engineers have an undergraduate or graduate degrees in biomedical engineering, mechanical engineering, or electrical engineering. A Portuguese university provides an undergraduate degree and a Master's degree in Rehabilitation Engineering and Accessibility. Qualification to become a Rehab' Engineer in the UK is possible via a University BSc Degree course such as Health Design & Technology Institute, Coventry University.

The rehabilitation process for people with disabilities often entails the design of assistive devices such as Walking aids intended to promote the inclusion of their users into the mainstream of society, commerce, and recreation.

3.6. Answer the questions:

1.What does rehabilitation engineering deal with?

2.Is a Master’s degree necessary to have to become a rehabilitation engineer?

3.Does rehabilitation engineering develop any devices for people?

4.What is the purpose of rehabilitation engineering?

5.What specialties can be a base for getting a job in rehabilitation engineering field?

3.7.Find the Gerund, the Infinitive and the Participle forms in the text. State the forms and functions.

3.8.Write a summary of the text.

3.9.Choose one aspect of Rehabilitation engineering and make a report. Present it to the class.

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2. Read and translate the text, make the glossary to it. Write the summary of the text.

Biotransducer

Biosensors can be classified by their biotransducer type. The most common types of biotransducers used in biosensors are:

electrochemical biosensors

optical biosensors

electronic biosensors

piezoelectric biosensors

gravimetric biosensors

pyroelectric biosensors

magnetic biosensors

Electrochemical biosensors are normally based on enzymatic catalysis of a reaction that produces or consumes electrons (such enzymes are rightly called redox enzymes). The sensor substrate usually contains three electrodes; a reference electrode, a working electrode and a counter electrode. The target analyte is involved in the reaction that takes place on the active electrode surface, and the reaction may cause either electron transfer across the double layer (producing a current) or can contribute to the double layer potential (producing a voltage). We can either measure the current (rate of flow of electrons is now proportional to the analyte concentration) at a fixed potential or the potential can be measured at zero current (this gives a loga-

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