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The correct ANSWER is (c) FREQUENCY of radiation

For explanation I would say: The angular frequency (Larmor frequency) of this precession is given by:

W = 2p v = r Bo

Where r is the ratio of the magnetic MOMENT to the angular MOMENTUM (the magnetic gyro ratio) and Bo is the density of the steady magnetic field and v is the frequency of radiation.

Correct option is (d) 102 micrometer

For EXPLANATION: The capillary diameter for red cell COUNT is 72 um and the DILUTION factor is 63,000. For white CELLS, the diameter is 102 um, and the dilution factor is 630. For platelet count, the diameter of the capillary is 72 um and a dilution of 6300 is used.

Correct option is (b) S plus Coulter counter

Explanation: As the instrument detects fewer PULSES than are actually present, to render the total COUNT accurate, it is necessary to add on the pulses that have been ‘lost’ due to coincidence. The rate at which this happens has been MATHEMATICALLY determined. Model S-plus Coulter counter automatically compensates for this LOSS.

Right answer is (d) 200 u, 0.04

The explanation: TAYLOR (1970) suggests that an aperture diameter of 100 m would be generally useful. For such an aperture, a length of about 200 μ and FLOW rate of 0.04 ml/s would be optimum. The aperture can be made using ruby watch JEWELS BONDED to a glass surface.

Correct answer is (d) Mean cell volume

To EXPLAIN: The Coulter counters are usually provided with an oscilloscope monitor to display the pulse information, which has passed through the amplifier, and acts as a VISIBLE check on the counting PROCESS indicating instantaneously any malfunctions such as a blocked orifice. In particular, it provides information regarding (i) RELATIVE cell size, (ii) relative cell size distribution, (iii) settings of the threshold level control, and (iv) means to check the performance of the instrument for the RELIABILITY of counts.

Right CHOICE is (c) span

For explanation I would say: The total operating range of the TRANSDUCER is called the span of the transducer. Offset is the output that will exist when it should be zero. DRIFT is basically the CHANGE in a signal over a LONG period of time.

The correct choice is (a) Morphology CHARACTERIZATION

Best explanation: Morphology characterization is based on analyzing the shape of the QRS complexes and separating beats into groups or clusters of similar morphology. Most algorithms for real time arrhythmia ANALYSIS MAINTAIN no more than 10-20 clusters at a time, order to limit the amount of computation needed to assign a QRS complex to a CLUSTER.

The correct option is (d) 6/min or 12/min

For EXPLANATION: In the arrhythmia monitoring instrument, it GIVES alarm light signals WHENEVER the prematured or widened ectopic beat exist up to the RATE of 6/min or 12/min.It is one of the operating sequences of the arrhythmia monitoring instrument.

Right choice is (b) False

For explanation I would say: It is False. CHOPPER input dc amplifiers are preferred for low level inputs to instrumentation systems because of their high sensitivity, negligible drift and excellent COMMON mode rejection CAPABILITY. Their high frequency RESPONSE is limited to about ONE half of the input chopper frequency.

Right choice is (c) Golay LOGIC processor

To elaborate: Image Processor: The SYSTEM uses TWO computers. The second computer is a special purpose pattern recognition computer, the Golay Logic Processor (Golay, 1969), which enables the system to transform CELL pattern recognition information into differential results. Golay logic (Preston et al 1979) enables the system to ‘see’ a cell in much the same way as a technologist does.

Correct ANSWER is (d) 35 to 40

Explanation: The system is designed to analyze standard slides at a 35 to 40 slides per hour rate. The actual analysis task takes only 90 s. In FACT, the system largely DUPLICATES mechanically and opto-electronically, the manual PROCEDURES followed while examining blood smears with a microscope.

Correct CHOICE is (a) 70 kHz

The explanation is: The electronic circuit MUST have UPPER frequency response GREATER than 70 kHz. The preamplifier used in cell counters must be of very low noise preferably having noise voltage less than 2 nA at the required BANDWIDTH of 70 kHz.

Correct CHOICE is (b) Blood FLOW

For explanation: Blood flow is one of the most important physiological PARAMETERS and also one of the most difficult to measure ACCURATELY. This is because instruments for measuring the flow through blood vessels within the body have to meet certain stringent specifications; e.g. sensitivity and STABILITY requirements depend upon the magnitude of flow, location and the diameter of the individual vessels.

The correct CHOICE is (a) Sine wave electromagnetic flowmeter

The best explanation: In a sine wave flowmeter, the PROBE magnet is energized with a sine wave and consequently the induced voltage will also be sinusoidal in nature. The major problem encountered with the sinusoidal type of magnetic field is that the blood vessel and the fluid CONTAINED in it act as the secondary coil of a TRANSFORMER when the probe magnet is EXCITED.

Correct answer is (c) Homium oxide filter

To explain: Wavelength calibration of a spectrophotometer can be CHECKED by using a holmium oxide filter as a wavelength standard. Holmium oxide glass has a number of sharp ABSORPTION BANDS, which occur at PRECISELY known wavelengths in the visible and ultraviolet regions of the spectrum.

Correct option is (c) Rhythm labeling

Explanation: It is based on DEFINED sequences of QRS complexes. Rhythm labeling is the final stage in ARRHYTHMIA analysis. The analysis systems are HEAVILY oriented towards DETECTING ventricular arrhythmias, particularly single PVCs.

The correct choice is (c) carrier amplifiers

For explanation I would SAY: Carrier amplifiers are used with transducers which require an external source of excitation. They essentially contain a carrier oscillator, a bridge BALANCE and CALIBRATION circuit, a high GAIN ac amplifier, a phase-sensitive detector and a dc output amplifier. They are characterized by high gain, negligible drift, extremely low noise and the ABILITY to operate with resistive, inductive or capacitive type transducers.

Right choice is (a) True

To elaborate: True, The He–Ne laser operating at 632.8 nm wavelength is USED. The laser OUTPUT is coupled into the FIBRE using a converging lens, which results in an increased power density at the skin surface and thus enables the detection of flow in the more DEEPLY seated veins and arteries.

Right CHOICE is (a) ratio of magnetic moment to angular MOMENTUM

The explanation: The angular FREQUENCY (Larmor frequency) of this precession is GIVEN by:

W = 2p v = r Bo

Where r is the ratio of the magnetic moment to the angular momentum (the magnetic gyro ratio) and Bo is the density of the steady magnetic field and v is the frequency of RADIATION.

The correct choice is (d) Erythrocytes

Explanation: The system is capable of determining segmented neutrophils, bands, EOSINOPHILS, basophils, LYMPHOCYTES, and monocytes, as well as ABNORMAL cells such as atypical lymphocytes, blasts, nucleated red cells, and IMMATURE granulocytes. In addition, the system carries out the red cell morphology, evaluating size, shape, and colour, counts the reticulocytes, estimates the platelet count and plots a distribution of red cell diameters.

The correct answer is (b) SQUARE wave electromagnetic flowmeter

Easy explanation: This differs from a sine wave flowmeter in that the energizing voltage given to the magnet is a square wave and therefore, the induced voltage is also a square wave. The square wave flowmeter has less STRINGENT requirements of PHASE stability than the sine wave TYPE as it can suppress the QUADRATURE voltages relatively easily.

Correct answer is (d) N = HLV/E

For explanation: One great advantage of this instrument is that the clogging of the capillary is greatly eliminated by applying a bi-directional FLOW during the MEASUREMENT procedure. The number of PARTICLES N in a unit volume is determined from the RELATION,

N = HLV/E

where

H = factor of dilution

I = scaling factor of the counter

V = measured volume

E = result displayed on the DIGITAL display.

Right OPTION is (d) saturation

For explanation: Settling time is the time for the SENSOR to reach a stable output once it is turned on. The region in which the output does not change with an increase in the input is CALLED saturation. It is a static property of the transducer. Frequency response is the change of TRANSFER function with frequency, both in magnitude and in phase.

Correct option is (d) 6-14 micron

The EXPLANATION is: Ragweed pollen (19 micron in diameter) and polystyrene LATEX PARTICLES (6–14 micron in diameter) seem to meet these requirements. Of the two, polystyrene latex is preferred for calibration purposes (Thom, 1972). The particles when USED seldom plug the orifice. These can be conveniently obtained in the RANGE of 5 million particles per cubic mm.

Correct option is (c) Mean cell hemoglobin volume

To elaborate: It provides the universally accepted profile of white cell count, RED cell count, mean cell volume, haemotocrit, mean cell haemoglobin CONCENTRATION, mean cell haemoglobin and haemoglobin. Besides this, the FOLLOWING five parameters are presented: platelet count, red cell distribution WIDTH, mean platelet volume, PLATELETCRIT, and platelet distribution width.

The correct option is (b) SPAN

For explanation: Ability of the sensor to repeat a measurement when put BACK in the same ENVIRONMENT is CALLED repeatability. Input range is the range between the max and min values is applied parameter which can be measured.The total operating range of the transducer is called span of the transducer.

Right choice is (B) 12 bit

Easy explanation: In signal conditioning, ECG signal is amplified, filtered and digitized using an 8- or 12- bit analog-to-digital converter with a TYPICAL SAMPLING RATE of 250 Hz.

Correct option is (d) above 8.2 mm

For explanation I would say: Iron cored electromagnets are used in probes having a diameter between 1 to 8.2 mm, and air cored electromagnets are used in diameters above 8.2 mm. Cannulated probes for extracorporeal use can have GREATER field strengths and magnet size as the CONSTRAINT of SMALL size is no LONGER present.

Correct CHOICE is (a) True

Easy explanation: It is True. ECG signal is amplified and filtered with 0.05-100 HZ for diagnostic PURPOSES and 1-40 Hz for MONITORING purposes in signal conditioning.

The correct choice is (b) cosmesis

To elaborate: Orthosis is a modality-specific APPLIANCE that AIDS the performance of a function or movement by augmenting or ASSISTING the residual capabilities of that function or movement. Aesthetics of APPEARANCE is CALLED cosmesis.

The CORRECT answer is (a) Plastic fibre

To explain I would say: In principle, light from a low power (5 mW) He–Ne laser is coupled into a quartz fibre and transmitted to the skin. The light is reflected from both the non-moving tissues (REFERENCE BEAM) and moving red blood cells (Doppler-shifted beam). The TWO beams are received by a plastic fibre and transmitted back to a photo-diode where optical heterodyning takes place.

Right OPTION is (a) 1 MM

The explanation: The effective radiation penetration depth is approximately 1 mm in SOFT tissue and scattering and absorption take place mostly in the papilla region and the underlying corium—two dermal layers containing the capillary network of the SKIN.

The correct answer is (c) sensitivity

To elaborate: The sensitivity of the sensor is defined as the SLOPE of the output characteristic curve. In SIMPLE words The minimum input of physical PARAMETER that will create a detectable out change is called sensitivity. Total operating range of the transducer is called its SPAN.

Right choice is (a) Pathophysiology

Explanation: Modality-Specific is a task that is specific to a single SENSE or movement pattern. Interruption or interference with normal physiological and developmental processes or structures is calledPathophysiology.A functional LIMITATION is a restriction or lack of ability to perform an ACTION in the MANNER or within the range consistent with the purpose of an organ or organ system.

Right answer is (d) COINCIDENCE error

Best explanation: Coincidence error occurs when two or more particles are present in the sensing ZONE at the same time. This will result in the instrument DETECTING fewer particles that are ACTUALLY present. This will also result in the instrument adding the pulses together to produce a single much longer PULSE.

Correct option is (a) LOW frequency noise, motion noise

To elaborate: The DETECTION filter removes low frequency noise (baseline wander) and MUSCLE artifact. The ECG waveform is processed by two digital filters: a detection filter and a classification filter.P waves and T waves are diminished.

Right choice is (b) TWO steps

Explanation: The ECG is first preprocessed to enhance the QRS complex while suppressing noise, artifact and non-QRS portions of the ECG. QRS detection is now almost UNIVERSALLY performed DIGITALLY in a two-step process. The output of the preprocessor stage is SUBJECTED to a decision RULE that confirms detection of QRS if the processor output exceeds a threshold.

The correct answer is (c) 150 MW

For EXPLANATION I would say: The preamplifier USED by Goodman (1969(a)) has a CMRR of 106 dB (200,000 : 1) with a common mode INPUT IMPEDANCE of 150 MW. The preamplifier gain is of the order of 1000. The preamplifier also must incorporate the FACILITY for ‘probe balance’ by which signals in phase with the magnet current can be selected to balance background voltages in phase with flow voltages. A calibrating signal of 30 mV amplitude can be connected to the preamplifier with an input selector switch.

Right answer is (d) Mixing coils and DELAY coils

Explanation: TWO types of coils are employed in the system—mixing coils and delay coils. Coils are glass spirals of critical dimensions, in which the mixing liquids are inverted several times, so that complete mixing can result. Mixing coils are used to mix the sample and/or reagents. Delay coils are employed when a specimen MUST be DELAYED for the completion of a chemical reaction before reaching the COLORIMETER.

Correct option is (b) False

Easy explanation: Typically, an aperture of 100 u diameter and 200 m LENGTH, separating two SOLUTIONS of PHOSPHATE buffered saline, has a RESISTANCE of about 25 kW and capacitance of 120 pF.

Correct choice is (c) 3

The explanation: Chopper stabilized dc AMPLIFIERS are used for low level but preferably wideband applications such as oscilloscopes, tape recorders and LIGHT BEAM oscilloscope recorders. This includes an ac amplifier for SIGNALS above about 20 Hz, a dc chopper INPUT amplifier for signals from about 20 Hz down to dc plus wideband feedback stabilized dc amplifier. These are complex amplifiers having three amplifiers incorporated in the module.

Correct choice is (c) THERMOCOUPLE

To elaborate: Thermocouple has the widest range of temperature measurement from -184*C to +2300*C. RTD has a range of -200*C to +850*C. Thermistor has a range of 0*C to 100*C WHEREAS conventional mercury thermometers range is -37*C to +356*C.

Right choice is (a) True

Explanation: The junction at a lower temperature in the THERMOCOUPLE is called the reference temperature. The cold junction is USUALLY KEPT at 0*C. The junction at a HIGHER temperature in thermocouple is termed as MEASURING junction.

Right answer is (a) True

To elaborate: True, for blood flow measurement WORK, behaviour of the two hydrogen atoms of WATER is studied, since blood is approximately 83% water. Due to the MAGNETIC moment of the hydrogen atom, the nucleus BEHAVES as a microminiature magnet which can be affected by externally applied magnetic fields.

The correct answer is (B) DOPPLER-shift

For explanation: For routine clinical measurements, the transcutaneous Doppler instrument has, by FAR, superseded the transit-time type. Therefore, most of the RECENT efforts have been concentrated on the development of Doppler-shift instruments, which are now available for the MEASUREMENT of blood velocity, volume flow, flow direction, flow profile and to visualize the internal lumen of a blood vessel.

Correct answer is (a) True

Easiest EXPLANATION: Assuming Gaussian distribution, the mean statistical error means that 67% of tests FALL into the INTERVAL (N +or- under-root n) with 33% of the measurements greater than that. To obtain the statistical error, the instrument reading should be multiplied by the scaling factor of the COUNTER. This will yield the value of n.