Week 1 Flashcards
peta
P 10^15
tera
T 10^12
giga
G 10^9
mega
M 10^6
Kilo
K 10^3
HECTO
h 10^2
deca
da 10
deci
d 10^-1
centi
c 10^-2
milli
m 10^-3
micro
μ 10^-6
nano
n 10^-9
SI unit for length
m
SI unit for mass
kg
SI unit for volume
CM3
SI unit for temperature
K
SI unit for amount of material
mol
Inferential Statistics is…
used to draw conclusions about the data
population
group from which data is colelcted
sample
a subset of population
variable
feature characteristic differing in quality of quantity from one member to another
Categorical variables
variables with discrete or qualitative values
continuous variables
variables that can be measured along a continuum
Nominal
no intrinsic order
Ordinal
have order (categorical)
dichotomous
only 2 values
interval
continuous variable, has numeric value and is measure
Ratio
like interval, but value of 0 indicates there is nothing
chance
Caused by random variations in subjects and measurements. BIgger sample size reduces this and statistical analysis will handle it
bias
not caused by random variation but by systematic variation. Big sample size will not fix this
selection bias
biased sampling of population
measurement bias
systematic bias with poor mesurement technique
analysis bias
favoring one analysis over the other
confounding
misinterpretation of accurate variables
clinical trial ( non randomized)
Experimental study where exposure status is assigned by investigator
Randomized controlled trial
experimental, Clinical trial when assignement to an exposure is determined purely by chance
Cohort study
Observational, analytical study in which subjects with an exposure of interest and subject without the exposure, are identified and then followed forward in time to determine outcome
Case-control study
observational, analytical study that first identifies group of subjects with disease and a control group without disease and looks back in time to find exposure. Works well with rare diseases
Cross-sectional study
Observational, analytical study that is done to examine presence or absence of dx or presence or absence of exposure at a particular time. Often unlcear if exposure preceded the outcome.
Case report
Descriptive study that reports on single or series of patients with certain diseases. Study usually generates a hypothesis but cannot test a hypothesis because it does not include appropraite comparison group.
Confounding
Occurs when investigator falsely concludes that a particular exposure is causally related to a dx without adjusting for other factors that are known risk factors for the dx and are associated with exposure
Standard error of mean
describes amount of variability in the measurement of the population mean from several different samples. This is in contrast to standard deviation; which measures the variability of individual observations in sample
Incidence
number of new events that occur during a specified period of time
Incidence rate
number of new events that occur over the sum of time individuals in the population were at risk for having the event
Prevalence
number of persons in population affected by dx at specific time divided by persons in the population
Number needed to treat
number of patients to treat to prevent one adverse outcome. Reciprocal of absolute risk reduction
Sensitivity
ability of test to identify correctly those who have the disease
Specificity
ability of test to identify correctly those who do not have the disease
Predictive values
assesses how useful a test will be in the clinical setting
positive predictive value
probability of dx in patient with positive test
negative predictive value
probability patient does not have disease if he has a negative test result
Type 1 error (alpha)
probability of incorrectly concluding there is a statistically sig diff in population when none exists
Type II error
probability of incorrectly concluding that there is no statistically sig diff in population when one exists/
Newton’s First Law
Object in motion stays in motion
Newton’s Second Law
Object will stay in motion until acted on bya force F=MA
Newton’s Third Law
For every action there si an equal and opposite reaction
Mass unit
kg
Velocity Units
m/sec
Acceleration units
m/sec2
Force units
kg*m/sec2
mass equation
m=f/a
velocity equation
Δx/t
Acceleration equation
Δv/Δt
force equation
m*a
scalar
magnitude and unit but no direction
vector
magnitude, units and direction
4 fundamental forces strongest to weakest
1) strong nuclear force
2) electromagnetic
3) weak nuclear force
4) gravitational forces
strong nuclear force
holds protons and neutons together in nucleus
electromagnetic force
holds electrons in atoms, tries to force protons apart
weak nuclear force
affects subatomic particles
gravitational force
holds earth in sun’s orbit and keeps you from floating away
Units of weight
pound. measure of force m*g
scales measure -___
weight
balance measure ____
mass
specific gravity
density of substance divided by the density of water. unitless
density units
mass/volume g/ml
pressure
force/area
barometer
atmospheric pressure to a vacuum. pam=p.g.h
manometer
compares atmospheric pressure to unknown pressure. Δp=pgΔh
aneroid bellow gauge
use expansion of bellows by pressure
bourdon gauge
use coiled tube that straightens in response to pressure
total pressure
ptotal=pgauge +patm
work definition
force acting through a distance fd or Nm
work/energy units
nm or 1kgm2/sec2
potential energy example, equation
lifting up an object. mgd
kinetic energy example, equation
pushing a car and accelerating it. 1/2mv2
power definiton
rate of work, work/tim
power units
1 watt=1 j/sec= 1 kg*m2/sec3
0th law of thermodynamics
A&B are in thermal equilibrium if they have the same temp
1st law of thermodynamics
ΔU= Q+W, change in internal energy= energy put into system+work done on system
2nd law of thermodynamics
Heat flows from hot to cold
3rd law of thermodynamics
It’s impossible to reach absolute zero
endothermic process, what does q equal?
energy flows into system (appears colder) Q>0
exothermic procss, what does q equal?
energy flows out of system (appears hotter) Q<0
temperature
average kinetic energy of particles
W and Δu at compressor
w>0, Δu>0
Q and ΔU at condenser and fan
Q<0, ΔU ABOUT 0
W and ΔU at beginning of evaporator
W <0, Δu <0
Q and Δ U at end of evaporator
Q>0, ΔU~0
4 types of matter
atoms, ions, elements, compounds
physical properties
intrinsic or extrinsic to matter
intrinsic property
indpendent of amount of material, color, density etc
extrinsic property
dependent on mass, volume, etc
atomic number
Z. #protons in nucleus. determined by atomic number
atomic mass
protons+#neutons
isotope
has diff number of neutrons. A-Z
mass spectrometer
used to determine varying isoptops.
covalent bonds
strong bonds between non metals. very strong in both water and air
ionic bonds
between metal and non metal. only strong in vacuum
hydrogen bonds
attraction of h to O and N (partial + and -)
van der waals
attraction between all atoms. very weak
list bonds from strongest to weakest
covalent, ionic, hydrogen, hydrophobic, van der waals
dinitrogen monoxide (nitrous oxide)
N2O
nitrogen monoxide (nitric oxide)
NO
Sodium ion?
Na+
Potassium ion?
K+
Calcium ion charge?
Ca2+
Chloride ion charge?
CL-
Sulfide ion
S2-
Phosphide ion
P3-
Copper I, cuprous
CU +
Copper II
CU 2+
Iron II, ferrous
Fe 2+
iron III, ferric
Fe3+
Ammonium
NH4+
Ammonia
NH3+
Hydronium
H3O+
Bicarbonate
HCO3-
Bisulfate
HSO4-
Hydroxide
OH-
acetate
C2H3O2-
cyanide
CN-
Dihydrogenphosphate ion
H2PO4-
Sulfate ion
SO42-
Nitrite
no2-
hypochlorite
ClO-
Carbonate
CO32-
Phosphate
PO43-
Nitrate
NO3-
Sulfite
SO3 2-
Sulfate
SO4 2-
hydrate
ionic compounds with fixed number of water molecules
electrolyte
substance that dissolves in water and conducts electricity
Mendeleev
organized the known elements in periodic table
Dalton
credited with atomic theory
Representative elements
Group 1a-8a
Transition elements
Middle group B elements
Mean, median mode with nominal?
No mean, no median, yes mode
Mean, median and mode with Ordinal?
Mean, maybe but no real value. Median Yes, Mode Yes
Mean median mode with Dichotomous
No mean, no median, yes mode
Mean, median mode with interval
Yes mean, yes median, yes mode
Mean, median mode with ratio
Yes mean, yes median, yes mode
Relative risk is for?
For cohort studies. Ratio of incidence of dx in exposed group divided by corresponding incidence of dx in unexposed group. Framington study with exposure of HTN and following amt of cardiac events in subjects with and without HTN. helped determine cardiac risk factos
Odds Ratio is for?
and case control studies. Odds of exposure in the group with dx divded by odds of exposure in control group. I.e. case control with relationship b/w artificial sweeteners and bladder ca. Odds ratio gives stable, unbiased estimate of relative risk./
