Download Medical physics of diagnostic and therapeutic equipment_2

Department of medical physics diagnostic and treatment equipment
Specialty: “medicine”, “dentistry”, “pharmacy”
Module 2. Operation of complex hardware medical systems
Transmittance of light
A. the ratio of the intensity of the reflected light to the intensity of light incident on the body
B. the reciprocal value of the distance at which the light intensity by absorption in the medium is
weakened at times
C. the ratio of the absolute refractive index of the second medium to the index of the first medium
D. the ratio of the radiation flux that has passed through this body, the radiation flux that fell on the
body
E. no correct answer
ANSWER: E
Concentration colorimetry
A. method for determining the concentration of colored solutions by measuring the intensity of the
light beam passed through the solution
B. method for determining the concentration of solutions by recording thermal study
C. method for determining the concentration of colored solutions the angle of rotation of the
polarization plane
D. method for determining the concentration of a solution by measuring the reflection coefficient
E. no correct answer
ANSWER: A
What is the plane of polarization of light?
A. plane , which varies the light vector and the velocity vector of light
B. plane in which the incident beam
C. plane in which the reflected beam
D. plane in which lie both the incident and reflected rays
E. no correct answer
ANSWER: A
The endoscope.
A. device for removal of gastric juice.
B. a device for determining the concentration of the substance.
C. device for viewing internal cavities of the body.
D. apparatus for studying the retina.
E. no correct answer
ANSWER: C
Radio radiation, in-use with a medical purpose.
A. mesons, hyperons
B. ultraviolet, beta ray
C. protons of high energy
D. gamma-radiation, alpha rays, neutrons.
E. all of answers are correct
ANSWER: B
Radio-activity.
A. spontaneous disintegration of unsteady kernels
B. electric activity of ions and free radicals
C. spontaneous synthesis of unsteady kernels
D. amount of particles, appearing for time unit at disintegration of radio-active kernels
E. all of answers are correct
ANSWER: A
Radioautographicprinting.
A. a method of estimation of concentration of isotopes is in the probed tissue
B. method of estimation of biological activity of surface of the probed tissue, exposed to the rays
radio-active elements
C. method of establishment of distributing of radionuclide in the probed tissue by the receipt of
their pictures on a photographic plate
D. use of mineral waters, containing a radon and his daughter's products, for affecting skin, organs
of digestion, breathings
E. all of answers are correct
ANSWER: C
Radioimpulse signal - it
A. always impulse of exponential form
B. brief deviation of tension or current from a permanent level
C. always impulse of rectangular form
D. always heteropolar impulse
E. brief parcel of sinusoid tension or current
ANSWER: E
Radioliz.
A. disintegration of difficult matter on component parts at influence a radio-active radiation
B. formation of difficult matter from components at influence an ultraviolet
C. chemical transformations of matters, looked after at influence an electric current
D. chemical transformations of matters, looked after at influence on them ionizing particles
E. all of answers are correct
ANSWER: D
Radon therapy.
A. treatment of organism by pills which radio-active elements enter in the complement of
B. respiratory exercises are in an atmosphere the isotope of radon and his daughter's products is
included in which
C. therapy, based on introduction to the organism of preparations, rich in a radon and his daughter's
products
D. use of mineral waters, containing a radon and his daughter's products for affecting skin, organs
of digestion, breathings.
E. all of answers are correct
ANSWER: D
Relative biological efficiency (coefficient of quality).
A. shows in how many times efficiency of biological action of this type of radiation more than
action x-ray photography or -radiation gat absorbe an identical dose
B. characterizes in how many times efficiency of biological action of this type of radiation more
than action of beta- and alpha -radiation at absorbe an identical dose
C. energy of ionizing radiations, taken in 1 kg of tissue of organism
D. size, numeral equal to the electric charge, to arising up under the action of gamma - and x-ray
photography radiation in 1 qube cm of dry air
E. all of answers are correct
ANSWER: A
Scintiscanners (gamma -topographer).
A. devices for establishment of the spatial distributing in the organism of radionuclide
B. devices, determining nature of radio-active element, patient artificially entered in an organism
C. devices, comparing the image of sick tissue with the image of healthy tissue
D. devices by which determine the amount of isotopes in an organism
E. all of answers are correct
ANSWER: A
Sources of ionizing radiations.
A. incandescent lamps, gas-unloading lamps
B. strongly heated solids, electric digits, gases, placed in the strong magnetic fields
C. x-ray photography tube, kernels of radio-active atoms, accelerating of the charged particles
D. ultra-high frequency apparatus, microwave frequency, extremely high frequencies apparatus
E. all of answers are correct
ANSWER: C
That a beta-radiation is
A. stream of kernels of helium
B. stream of electrons and positrons
C. stream of kernels of hydrogen
D. stream of protons and mesons
E. all of answers are correct
ANSWER: B
That is alpha emission
A. stream of electrons
B. stream of kernels of helium
C. stream of protons
D. stream of kernels of atoms of hydrogen
E. all of answers are correct
ANSWER: B
That is Bekkerel' (Bk), as a metage activity of radio-active preparation It is such metage, when after
1 with takes a place ( 10^8 10 power 8)
A. 1 act of disintegration;
B. 3,7*10^10 acts of disintegration;
C. 10^6 acts of disintegration;
D. 10^9 acts of disintegration
E. all of answers are correct
ANSWER: A
The atom of lithium is contained by 3 electrons, 3 protons and 4 neutrons. His atomic mass number
makes: .. .
A. 3
B. 6
C. 4
D. 10
E. 7
ANSWER: E
The current of electric displacement renders in a vacuum ...........
A. thermal, magnetic and chemical actions
B. thermal and magnetic actions
C. thermal and chemical actions
D. magnetic and chemical actions
E. only magnetic action
ANSWER: E
The isotope of cobalt (Со) is known as a source of ionizing radiation. A radiation is determined the
proper device. When the piece of lead in 20 mm thick is set as an absorber between a cobalt source
and this device, a radiation continues to be fixed a device. This radiation is: ..
A. beta particles
B. alpha-particles
C. are HS atoms of cobalt
D. HS kernels of cobalt
E. gamma-rays
ANSWER: E
The kernel of atom consists of 90 protons and 144 neutrons. After emitting of two beta particles,
and then one alpha-particle this kernel will have: ...
A. 85 protons and 140 neutrons
B. 87 protons and 140 neutrons
C. 96 protons and 142 neutrons
D. 90 protons and 142 neutrons
E. 90 protons and 140 neutrons
ANSWER: E
The varieties of atoms of one element, differentiating the masses of atomic kernels and number of
neutrons in a kernel, are named ....
A. nucleoside.
B. isotone.
C. by isobars.
D. nucleotide.
E. by isotopes
ANSWER: E
The varieties of atoms the kernels of which contain the different number of protons, but identical
number of neutrons, are named .... .
A. by isobars
B. by isotopes
C. nucleotide
D. nucleoside
E. isotone
ANSWER: E
The variety of atoms the kernels of which have a certain number of protons and neutrons is named
....
A. isotone.
B. isobar .
C. by an isotope.
D. nucleotide .
E. nucleotide.
ANSWER: E
Thermal effect at procedure ULTRA HIGH FREQUENCY determined
A. heat transfer
B. by absorption of infra-red radiation
C. by a joule heat
D. by the action of vortical currents of Fuko
E. by the dielectric losses
ANSWER: E
Tissue of electric current of conductivity ...........
A. straight proportional the concentration of transmitters of charge in an explorer
B. inversely the concentration of transmitters of charge in an explorer
C. determine only by the concentration of transmitters of charge in an explorer
D. can not be equal to the zero
E. inversely the concentration of transmitters of charge in an explorer
ANSWER: E
Tissue of electric current of conductivity ........... .
A. determined only the concentration of transmitters of charge in an explorer
B. straight proportional thermal speed of transmitters of charge
C. back proportional a drift speed of transmitters of charge
D. does not depend on mobility of transmitters of charge
E. straight proportional a drift speed of transmitters of charge
ANSWER: E
To the ionizing radiations, to in-use in medicine belong ultraviolet and all of range of visible
radiation
A. ultrahigh-frequency, super-high-frequency electromagnetic radiation
B. ultrasonic and microwave electromagnetic radiation
C. x-ray photography and gamma of radiation
D. there is not a right answer
E. all of answers are correct
ANSWER: A
Transformation of energy of the electromagnetic field to thermal energy in the matter of dielectric is
named .......... .
A. by diathermy
B. inductothermy
C. through warming up
D. through warming up
E. by the dielectric losses
ANSWER: E
Transformation of energy of the electromagnetic field to thermal energy in the matter of explorer
due to flowing on the explorer of direct current of conductivity is named .......... .
A. by diathermy
B. inductothermy
C. by dielectric losses
D. through warming up
E. by formation of Joule heat
ANSWER: E
Types of detectors.
A. devices of reflection of information
B. meters of impulses of current, tension and electromagnetic radiation
C. track detectors, meters and integral devices
D. detectors of pressure
E. all of answers are correct
ANSWER: C
Unit of display dose of photonic ionizing radiation in SI is ...... .
A. gray
B. sievert
C. kerma
D. x-ray photography
E. coulomb on a kilogram
ANSWER: E
Unit of eaten up the dose of ionizing radiation in SI is ...... .
A. x-ray photography
B. coulomb on a kilogram
C. sievert
D. kerma
E. gray
ANSWER: E
Unit of equivalent dose of ionizing radiation in SI is ...... .
A. x-ray photography
B. coulomb on a kilogram
C. gray
D. kerma
E. sievert
ANSWER: E
What was the first solid state laser created?
A. Excimer laser
B. Neodymium glass laser
C. Garnet crystals laser
D. Helium-neon laser
E. Ruby laser
ANSWER: E
What does acronym “laser” stand for?
A. Living Amplification of Solidly Emitted Radiation
B. Light Amplification by Stimulated Emission of Radiation
C. Long Amplitude of Simulated Emission of Radiowaves
D. Light Appearance by Spontaneous Emission of Radiation
E. Lasting Amplification for Special Emission of Radiation
ANSWER: B
What is not a physical property of a laser beam?
A. The efficiency of about 1%.
B. Coherent
C. Collimated
D. Continuous
E. Small divergence angle of the light beam
ANSWER: D
The value of monochromaticity of laser beam ((delta v)/v, delta nu/nu) is ____
A. Always equals to 0
B. Within the range of 10-12 to 10-13
C. Always equals to 1
D. Within the range of 0 to 1
E. Within the range of 1012 to 1013
ANSWER: B
Name a component that is NOT a part of optical cavity of a laser:
A. A lasing (or “gain”) medium
B. Highly reflective mirror
C. Partially reflective mirror
D. Resonator
E. An energy source or a pump
ANSWER: E
Excimer laser wavelength is within
A. Ultraviolet range
B. Visible range
C. Infrared range
D. X-ray range
E. None of the above
ANSWER: A
CO2 laser has a wavelength of emitted electromagnetic radiation of approximately ____
A. 100 nm
B. 500 nm
C. 1000 nm
D. 5000 nm
E. 10000 nm
ANSWER: E
Excimer laser used for eye surgery is a combination of
A. Atoms from the X state and atoms from the C state
B. Helium molecules and Neon molecules
C. Two highly active molecules from halogen element
D. Noble gas molecules and halogen element molecules
E. A mix of different noble gas molecules
ANSWER: D
In this type of lasers there is no discrete energy levels of lasing medium atoms, but rather energy
bands that electrons jump between.
A. Semiconductor based laser
B. Chemical lasers
C. Excimer lasers
D. Gas laser
E. Dye laser
ANSWER: A
As the wavelength decreases towards the ultraviolet spectrum, ___
A. lasers become of less and less use
B. the depth penetration of live tissues increases
C. the depth penetration of live tissues decreases
D. the depth penetration of live tissues stays the same
E. the light scattering decreases
ANSWER: B
This component of a laser produces/is a source of quanta of energy, hv
A. Output coupler
B. Partially reflective mirror
C. Optical resonator
D. Lasing medium
E. Highly reflective medium
ANSWER: D
This component of a laser is a barrel where stimulated emission takes places and masses of quanta
of energy, hv, are produced.
A. Output coupler
B. Partially reflective mirror
C. Optical resonator
D. Lasing medium
E. Highly reflective medium
ANSWER: C
This component of a laser is a small opening where laser beam exits the system.
A. Output coupler
B. Partially reflective mirror
C. Optical resonator
D. Lasing medium
E. Highly reflective medium
ANSWER: A
When photon hits an excited atom, and excited atom goes back to a ground state, producing two
identical photons, the process is known as______
A. Ionizing radiation
B. Higher energy orbital conversion
C. Colliding
D. Spontaneous emission
E. Stimulated emission
ANSWER: E
The output of continuous wave lasers is measured as ____
A. force in newtons
B. energy in joules
C. power in watts
D. fluence, or irradiance multiplied by exposure time
E. wavelength in nanometers
ANSWER: C
The output of pulsed lasers is measured as ____
A. force in newtons
B. energy in joules
C. power in watts
D. fluence, or irradiance multiplied by exposure time
E. wavelength in nanometers
ANSWER: B
Water predominantly absorbs ____
A. UV light
B. Infrared light
C. Visible light
D. UV light and infrared light
E. Infrared light and visible light
ANSWER: B
Speaking of medical lasers, which category based on safety do they belong to?
A. Class 1M
B. Class 1
C. Class 4
D. Class 2M
E. Class 3B
ANSWER: C
Which part of an eye is reshaped during Lasik laser remodeling?
A. Cilliary muscle
B. Upper portion of cornea
C. Corneal stroma
D. Retina of an eye
E. Eye lens
ANSWER: C
In cardiology, this type of laser is used to improve blood flow to the heart
A. Excimer laser
B. CO2 laser
C. Nd and Glass laser
D. Helium Neon laser
E. None of the listed here
ANSWER: B
What is NOT true about MPE, regarding laser safety?
A. It is a calculation of the highest power density (W/cm2) or energy density (J/cm2) allowed for a
laser that is considered to be safe and unlikely to cause damage
B. It stands for Maximum Permeable Exposure (MPE) levels
C. It is measured at the skin or the cornea of the eye, for a given wavelength or exposure time.
D. The International Electrotechnical Commission (IEC) defines methods of calculating MPE
levels
E. The International Electrotechnical Commission (IEC) uses standard 60825-1 (2007) to calculate
and define MPE.
ANSWER: B
Among seven classes of lasers based on safety, Class 1M, 1, 2M, 2, 3R, 3B and 4, which one is the
safest?
A. Class 1M
B. Class 1
C. Class 4
D. Class 2M
E. Class 3B
ANSWER: B
In helium-neon laser, an auxiliary component is
A. helium
B. neon
C. helium and neon
D. none of the listed, as helium and neon gases are both primary lasing components
E. ruby crystal
ANSWER: A
Which of the following is not true about laser beam
A. it is monochromatic
B. it is collimated
C. it is always working in a pulsed mode
D. it is coherent
E. it can be of a specified wavelength
ANSWER: C
When electron drops from a higher quantum state to a lower quantum state in an atom,
A. a photon is absorbed
B. an electromagnetic energy is absorbed.
C. A single energy quantum, hv, is released
D. Atom collapses with formation of new chemical bonds
E. A new chemical element is formed
ANSWER: C
Light is ____
A. an electromagnetic wave only
B. a directional movement of particles – photons
C. a substance with dual properties, being both electromagnetic wave and particles – photons
D. ultrasound traveling at a light speed
E. infrasound traveling at a light speed
ANSWER: C
As a wavelength of electromagnetic wave decreases,
A. frequency increases and energy of a photon decreases
B. frequency decreases and energy of a photon decreases
C. frequency increases and energy of a photon increases
D. frequency decreases and energy of a photon decreases
E. frequency increases and energy of a photon stays the same
ANSWER: A
Which of the following is not part of the ionizing radiation?
A. Gamma rays
B. X-rays
C. Extreme UV light
D. Microwave
E. Soft X-rays
ANSWER: D
The time constant for spontaneous emission, that is represented by ?, is
A. There no such thing as a time constant, as spontaneous emission depends on temperature.
B. The maximal time it takes for the electron to decay from the higher state to a lower state
C. The longest time an unstable atom can exist in this unstable state
D. The longest time an unstable atom can exist in this unstable state
E. The average time it takes for the electron to decay from higher state to a lower state
ANSWER: E
CO2 laser is
A. an atomic laser
B. a laser that works with molecular transitions (vibrational and rotational states)
C. does not requires continuous replacement of a hot gas.
D. Cannot be used for material processing, or surgery.
E. None of the answers is correct
ANSWER: B
Those are lasers in which a population inversion is created between the excited vibrationalrotational levels of heteronuclear molecules by adiabatic expansion, moving at high speed gas
mixture
A. solid lasers
B. gas lasers
C. semiconductor-based lasers
D. gas-dynamic lasers
E. dye lasers
ANSWER: D
Irradiance, or power density of a laser, is ____
A. a dose of absorbed radiation, in rads per cm3
B. laser energy per unit area (J/cm2)
C. a dose of absorbed radiation, in rads
D. laser power per unit area (W/cm2)
E. none of the listed is correct
ANSWER: D
Artificialventilation- it ...
A. The method bywhich therestoredand maintainedimpairedlungfunction- ventilationand gas
exchange;
B. Allanswers are correct;
C. The method bywhichtreatspulmonarydisease;
D. The correct answer isno;
E. The method bywhichprovidefirst medicalauxiliaryin critical situations;
ANSWER: A
What are the main types of mechanical ventilation ?
A. 1;
B. 3;
C. 2;
D. 4;
E. 8;
ANSWER: C
Ventilation with positive pressure may be ...
A. Invasive;
B. Non-invasive;
C. All answers are correct;
D. There is no right answer;
E. Ventilation with positive pressure does not exist;
ANSWER: C
Clinical death - it ...
A. Cardiac arrest;
B. Short-term transitional stage between life and death;
C. All answers are correct;
D. Vidmerannya internal organs;
E. This clinical death from disease;
ANSWER: B
What are the main tasks of the center control ventilation ?
A. Monitoring of sensors and flow volume;
B. Management agreed work valves timely filing and cessation of oxygen- air mixture;
C. All answers are correct;
D. Responding to the rejection of certain parameters of a given ventilation installations;
E. There is no right answer;
ANSWER: C
Hemodialysis - it ...
A. Supports heart;
B. Mechanical cleaning the blood of waste products , salts and liquids;
C. Mechanical cleaning of plasma;
D. Mechanical cleaning of the lungs;
E. There is no right answer;
ANSWER: B
How many liters tank holds dializuyuchoho solution in the apparatus " artificial kidney "?
A. 123 l;
B. 115l;
C. 110 l;
D. 90 l;
E. 97 l;
ANSWER: C
Coefficient cleaning apparatus "artificial kidney" is ...
A. 180 ml / min;
B. 140 ml / min;
C. 100 ml / min;
D. 108 ml / min;
E. 160 ml / min;
ANSWER: B
What hydraulic unit performs tasks in the office of " artificial kidney "?
A. Conducts internal disinfection unit before and after hemodialysis;
B. Performs intake of dialyzer fluid dializuyuchoyi with ultrafiltrate;
C. All answers are correct;
D. Prepares dializuyuchu fluid from concentrate and purified water by mixing one part concentrate
and 34 parts of water;
E. If necessary, provide bypass dializuyuchoyi fluid past the dialyzer;
ANSWER: C
Ventricular fibrillation is ...
A. The most common cause of sudden cardiac arrest;
B. Cardiac massage and artificial respiration;
C. All answers are correct;
D. There is no right answer;
E. First aid for cardiac arrest;
ANSWER: C
That allows daily monitoruvannya blood pressure ?
A. Get information about the level and fluctuations in blood pressure during the day, during
wakefulness and sleep;
B. Identify patients with nocturnal hypertension;
C. Assess the adequacy of BP reduction between doses of regular doses of the drug;
D. All answers are correct;
E. There is no right answer;
ANSWER: D
What is the thickness of the membrane in the machine " artificial kidney "?
A. 8 microns;
B. 11 microns;
C. 15 microns;
D. 30 microns;
E. All answers are correct;
ANSWER: E
How long conducting hemodialysis
A. 3-6 hours;
B. 5-7 hours;
C. 6-7 hours;
D. 1-4 hours;
ANSWER: A
Ventilation with active inhalation and exhalation is active:
A. Ventilation with intermittent positive pressure;
B. Ventilation with intermittent positive- pressure zero;
C. Ventilation with intermittent positive- negative pressure;
D. Ventilation with intermittent positive- positive pressure;
E. Ventilation with negative pressure;
ANSWER: C
Short-term transitional stage between life and death - it ...
A. Agony;
B. Clinical death;
C. Preahonalnyy condition;
D. Biological death;
E. Shock;
ANSWER: B
Mechanical cleaning the blood of waste products , salts and fluids - it ...
A. Hemodialysis;
B. MRI;
C. CT;
D. ventilation;
E. Defibrillator;
ANSWER: A
For domopohoyu by which staff conduct hemodialysis ?
A. "Artificial kidney ";
B. Ventilator;
C. Defibrillator;
D. MRI;
E. There is no right answer;
ANSWER: A
What is the essence of artificial respiration ?
A. Forced entry of air into the lungs;
B. Cleaning lungs from harmful substances;
C. Treatment of Lung Cancer;
D. There is no right answer;
E. All answers are correct;
ANSWER: A
Reasons for failure defibrillation ?
A. Erroneous imposition of electrons;
B. Very low energy defibrillation;
C. All correct answers;
D. Inadequate myocardial oxygen saturation;
E. The high resistance of the skin;
ANSWER: C
Normal levels of saturation (SpO2) are:
A. 90-99%;
B. 35-44%;
C. 42% -67%;
D. 25-40%;
E. 95-98%;
ANSWER: E
Give the correct definition of artificial ventilation ?
A. The method by which a person is restored heart function during clinical death;
B. The method by which stops the normal functioning of the lungs;
C. The method by which the auxiliary restored impaired lung function - ventilation and gas
exchange;
D. The method by which the restored work of the human brain;
E. The correct answer is no;
ANSWER: D
What are the different types of mechanical ventilation ?
A. Allanswersarecorrect;
B. Ventilation with negative pressure;
C. Ventilation with positive pressure;
D. Ventilation with negative and positive pressure;
E. Ventilation without pressure on the lungs;
ANSWER: D
Ventilation with negative pressure produced ?
A. Inside effect on the wall of the chest cavity;
B. Inside the action of the diaphragm wall;
C. External influence on the diaphragm wall and the chest;;
D. External influence on the surface of the lungs;
E. Inside the action on the surface of the lungs;
ANSWER: C
Ventilation with positive pressure can be ....
A. Non-invasive;
B. Invasive;
C. Mechanical ventilation with positive pressure there;
D. Invasive or non-invasive;
E. The other option;
ANSWER: D
What part is not in the ventilator ?
A. ControlCenter;
B. Sources of medical gases;
C. Sensors control the flow and pressure;
D. Mixer oxygen and air;;
E. Power Supply;
ANSWER: E
Sources of medical gases is ......
A. Hospital Oxygen Plant;
B. All options are correct;
C. Directly from gas cylinders;
D. There is no right answer;
E. Oxygen concentrator;
ANSWER: B
The main task flow sensor ?
A. Analysis of expiration;
B. Analysis of breath;
C. Analysis of exhaled volume povidrya;
D. Analysis of the volume of air that vdyhuyetsya;
E. Analysis of heart rate;;
ANSWER: A
Under what conditions do hemodialysis ?
A. Human kidneys are functioning at 100 %;
B. Kidney patient functioning at 10-15%;
C. The kidneys are functioning at 60 %;
D. 45% kidney function;
E. The kidneys are functioning at 5%;
ANSWER: B
What is the thickness of the membrane in the machine " artificial kidney "?
A. 8 microns;
B. 11 microns;
C. 15 microns;
D. 30 microns;
E. 8, 11, 15 or 30 microns;
ANSWER: E
How many basic types of devices " artificial kidney "?
A. 3;
B. 5;
C. 2;
D. 6;
E. 1;
ANSWER: C
How long does an electric discharge in the defibrillator electrodes ?
A. To 1s..;
B. To 0.01 sec .;
C. Up to 10 sec.;
D. To 0.001 sec.;
E. Up to 1 min;
ANSWER: B
What voltage discharge defibrillator ?
A. 700 V;
B. 5000 V;
C. 7000 V;
D. 70 V;
E. 500 V;
ANSWER: C
DMAT is ?
A. Invazyvnyy survey method BP fluctuations;
B. Heinvazyvnyy method ostezhennya of the lungs;
C. Metod maintain a blood level;
D. Daily monitorynhuvannya blood pressure;
E. The daily variability of blood pressure;
ANSWER: D
What causes inefficient defibrillation ?
A. False overlapping electrodes;
B. Very low energy defibrillation;
C. Inadequate myocardial oxygen saturation;
D. The high resistance of the skin;
E. All options are correct;
ANSWER: E