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					       Effects of five common
       neurotransmitters on
      contraction of the crop-
      gizzard of the Lumbricus
             terretestris
TITLE – 1/1 POINT

Mention that you applied characteristics to determine an unknown. Cut out one of the “of the”s. Be
more specific with “effects”


1: Focused, descriptive, original title.
0: Title is vague or title is not descriptive or title is not original or title is too long




                                                 BMED 3110
                                                Ferocious Four
                                                  Ethan Lotz
                                              Kunal MacDonald
                                                Lance Whatley
                                              Sunil Yalamanchili
                                                   3/21/2011

The effects of five neurotransmitters (acetylcholine, atropine, epinephrine, norepinephrine, and
serotonin) were studied on isolated crop-gizzard preparations of Canadian Nightcrawlers
                                          Neurotransmitter effect on crop-gizzard contractility

Lumbricus terretestris suspended in a ringer solution. Using a force transducer and LabVIEW,
changes in the amplitude and frequency of contractions associated with spontaneous motility
were observed in response to neurotransmitters known to have excitatory effects and inhibitory
effects. The overall contractile amplitude of the crop-gizzard was significantly changed by
norepinephrine and serotonin, while the overall contractile frequency was significantly changed
by acetylcholine, atropine, and norepinephrine. Additionally, an unknown neurotransmitter was
tested and compared against the five originally tested neurotransmitters. Through a regression
analysis it was surmised that the unknown was serotonin. When cross-referencing our results
with previously conducted experiments, it was found that the effects of epinephrine on the crop-
gizzard are not consistent with one another. This inconsistency suggests that there may be one or
more confounding factors that have not been considered

ABSTRACT – 2/3 POINTS

Experimental techniques not described thoroughly enough (be brief, but complete). Need more
discussion of results. How was the identity of the unknown neurotransmitter determined? Concluding
sentence could be stronger?

The abstract has five elements:

   o   Less than 250 words (i.e., one double-spaced page)
   o   Introductory statement that places article in context; purpose
   o   Summary of experimental techniques and analysis methods (include number of subjects,
       controls, main variables/measures)
   o   Highlights interesting results
   o   Highlights interesting conclusions

       3: Has all five elements
       2: Missing one of the five elements
       1: Missing two of the five elements
       0: Missing more than two of the five elements




Introduction

       Compared to skeletal muscle, smooth visceral muscle contraction is often much slower

and prolonged, requires less energy to cause a contraction, and can produce a larger force than

skeletal muscle. Another important characteristic of smooth muscle is that it can be stimulated

by not only the nervous system, but also by hormonal stimulation and stretch of the muscle. In

smooth muscle, acetylcholine and norepinephrine play important roles in muscle excitation and

inhibition. When acetylcholine excites the muscle, norepinephrine normally inhibits it and vice



                                                 1
                                           Neurotransmitter effect on crop-gizzard contractility

versa. Other neurotransmitters such as epinephrine, serotonin, and atropine all play roles in the

excitation or inhibition of smooth muscle (Guyton, 2006).


       Studying the effects of various neurotransmitters on smooth muscle in animals has played

an important role in understanding hormonal responses to smooth muscle tissue. The crop

gizzard of the Night Crawler earthworm Lumbricus terretestris is a smooth muscular organ

located in the gut that can be used to study the effects of neurotransmitters. Previously

acetylcholine has produced a sharp contraction on all parts of the gut of the earthworm. Atropine

has been shown to diminish the effects of acetylcholine, although by itself has been shown to

possess a slight excitatory response. Epinephrine (adrenaline) has been shown to have an

inhibitory response in the crop gizzard (Wu, 1938).


       Testing the differences between the effects of five neurotransmitters (acetylcholine,

epinephrine, norepinephrine, atropine, and serotonin) on the crop gizzard holds value in that it

can allow for understanding which particular chemicals transmit excitatory or inhibitory

responses to the muscle. It also allows for possibly determining an unknown hormone or

chemical that is acting on the muscle. This in turn can enhance future research of clinical drugs

associated with muscle stimulants or relaxants. It is estimated (is this the hypothesis?) that these

five different neurotransmitters act differently on the crop gizzard of the earthworm, and that an

unknown substance can be identified based on information gathered how?.


INTRODUCTION – 2/3 POINTS

Testable hypothesis poorly defined. Need more complete background. What are you going to actually
do? i.e. what are you going to measure? Motivation?

The introduction has three elements:

   o   A background of the problem area, sufficient that a learned person outside of the field will be
       able to understand the remainder of the report

                                                  2
                                              Neurotransmitter effect on crop-gizzard contractility

   o   A testable hypothesis
   o   A statement of purpose and applicability, i.e. how these results may affect the field


3: Has all three elements
2: Missing one of the three elements
1: Missing two of the three elements
0: Missing two or more of the four elements

Materials and Methods

Sample Size: The sample size was calculated by analyzing the data obtained from the

information provided previous experiment on a Canadian Night Crawler earthworm’s (Canadian

Night Crawler) crop gizzard (crop gizzard reaction to ringer solution). The program G-power

was used to conduct a matched paired t-test on the previous data with outliers removed. The

calculated sample size was 3 worms per neurotransmitter.

VI Preparation: The hardware was assembled as described in the materials provided. The

Measurement and Automation program on the computer was used to check which device port

(“Dev#”) the tension adjuster was attached to. Since the force transducer outputs values in

voltage, a series of conversions was performed to transform data into Newtons. A maximum

output voltage was found by tying a 50-g weight to the tension force sensor. The outputted data

was divided by the maximum voltage and multiplied by 50g. It was then divided by 1000g and

multiplied by 9.8 m/s2 giving it units of kg*m/s2, which is Newtons.

Earthworm Preparation and Dissection: All dissections and data collections were performed at

room temperature. The Canadian Night Crawler Earthworms were rinsed in a tap water bath to

clean off dirt. The earthworm was placed in a 50-ml conical tube containing 25% ethanol

solution for approximately 2-5 min to anesthetize it. Prior to dissection, excess anesthesia was

rinsed from the earthworm with Ringer’s solution. The earthworm was pinned dorsal side up in

a dissecting dish. A 3-6 cm incision was made along the midsection of the worm. Pins were

used to hold the incision open. The tegument was carefully cut to not damage any organs along
                                                    3
                                             Neurotransmitter effect on crop-gizzard contractility

the midsection and pinned through the anterior of the worm. Once the anterior organs were

exposed, the connective tissue around the crop-gizzard was carefully removed. The earthworm

was frequently irrigated with Ringer’s solution to prevent it from drying.

VI analysis of Earthworm Crop Gizzard: A tissue bath with of 100% Ringer’s solution was

prepared in a 50-ml conical tube and fixed under the force transducer. Once completely

detached from the tegument, a piece of silk thread was tied around opposite ends of the crop-

gizzard, making sure to leave enough thread to attach the crop-gizzard to the force transducer

and tissue weight (a normal Phillips-head screw). The crop-gizzard was then removed from the

worm, once the thread was securely fastened. The thread attached to the posterior end of the

crop-gizzard was tied to the tissue weight and deposited in the 100% ringer (Ringer’s versus

ringer? Be consistent) solution so it was completely submerged. The thread attached to the

anterior end was fastened to the force transducer. Thread slack was eliminated by adjusting the

height of the force transducer was adjusted to eliminate any slack that may have been present in

either side of the string. We waited one minute for the crop gizzard to acclimate to the new

concentration, and then recorded data for the next two minutes. The VI was run which gathered

the data (tone, frequency, and amplitude of what) for two minutes at a rate of 12 samples/sec

(Krajniak and Klohr, 2001). Noise in the measurements was eliminated by best-fitting a

sinusoidal curve. How? By least squared?


MATERIALS AND METHODS – 1/2 POINT

What method did you use to determine unknown identity? Unbalanced detail: too much in the VI prep,
not enough in statistics. I think I finally figured out how you’re doing statistics: determine dose
response, fit linear trendline, compare slopes/coefficients, right? It’s an interesting method, but is not
described well.
2: Concise description of materials and methods used including characteristics of subjects and
statistical analysis method used to directly test the hypothesis
1: Long description or methods missing some methods missing. Stats missing.
0: Anything else, i.e. long description and materials or methods missing



                                                    4
                                                 Neurotransmitter effect on crop-gizzard contractility




Results

Frequency of contractions of the Canadian Night Crawler crop-gizzard was significantly

affected by acetylcholine, atropine, and epinephrine. Norepinephrine, serotonin, and the

unknown had no significant effect on the frequency of contractions of the crop-gizzard.

Frequency is the number of occurrences of a repeating event per unit time. In this experiment,

the occurrence was a full contraction of the crop-gizzard muscle. To explore the in vivo effect of

                                 0.15

                                                        Figure 1: Statistically significant regression lines were
Frequency of Contractions (Hz)




                                 0.12                   detected between the frequency of contraction and
                                                        neurotransmitter dose for acetylcholine, atropine, and
                                                        epinephrine, and no statistically significant regression lines
  0.09                                                  were detected (?) for norepinephrine, serotonin, and the
                                                        unknown. The frequency of contraction was the number of
                                                        peaks in our observed data and divided by 120 seconds. An
  0.06                                   Acetylcholine analysis of regression was performed. Acetylcholine, atropine,
                                         Atropine       and epinephrine (p-values = 0.000, 0.000, 0.002 respectively)
                                         Epinephrine    were all found to be statistically significant, while
  0.03                                   Norepinephrine norepinephrine, serotonin, and the unknown (p-values = 0.146,
                                         Serotonin      0.807, 0.394 respectively) were not found to have a statistical
                                         Unknown        significance. How are the regression lines statistically
  0.00
     0.000 0.007 0.014 0.021 0.028 0.035                significant themselves? do you mean that the difference
                Dose (weight %)                         between them is significant? The wording could be improved.
the six neurotransmitters solutions (there are only Is the dose response linear in the literature?

five NT), the crop-gizzard was exposed to a neurotransmitter dose for two minutes. At the end

of two minutes the dose was increased. Figure 1 shows the dose response relationship between

each neurotransmitter’s dose and the frequency of contractions. Regression analysis detected

significant regression coefficients for acetylcholine (1.944), atropine (- 0.972), and epinephrine

(0.972). However, changes in contractile frequency were not statistically different from zero for

norepinephrine, serotonin, and the unknown




The amplitude of contractions of the Canadian Night Crawler crop-gizzard was significantly


                                                         5
                                                                                Neurotransmitter effect on crop-gizzard contractility

           affected by norepinephrine, serotonin, and the unknown. Acetylcholine, atropine, and

                                                                                                epinephrine had no significant effect on the
                        20
                                                                                                amplitude of contractions of the crop-gizzard.
Maximum Amplitude (N)




                        15                                                                      Amplitude is the magnitude of change in the

                        10
                                                                                                oscillating (poorly worded). Figure 2 displays
                                                                           Acetylcholine
                                                                           Atropine             the dose response of each neurotransmitter’s
                         5                                                 Epinephrine
                                                                           Norepinephrine
                                                                           Serotonin            maximum amplitude of contraction.
                                                                           Unknown
                         0
                         0.000   0.007     0.014   0.021   0.028   0.035                        Regression analysis of each neurotransmitter
                                         Dose (weight %)
           resulted in significant regression coefficients for norepinephrine (129.333), serotonin (-182.767),

           and the unknown (-231.647). However, changes in contractile frequency were to not statistically

           different than from zero (?) for acetylcholine, atropine, and epinephrine.



                                                                                                 Figure 2: : Statistically significant regression lines were
                                                                                                 detected between the maximum amplitude of
                                                                                                 contraction and neurotransmitter dose for
                                                                                                 norepinephrine, serotonin, and the unknown, and no
                                                                                                 statistically significant regression were detected for
                                                                                                 acetylcholine, atropine, and epinephrine. The maximum
                                                                                                 amplitude of contraction was the difference between the
                                                                                                 global maximum and the global minimum of the data set.
                                                                                                 An analysis of regression was performed on the data.
                                                                                                 Norepinephrine, serotonin, and the unknown (p-values p=
           The unknown neurotransmitter is most similar                                          0.015, 0.008, 0.011 respectively) were all found to be
                                                                                                 statistically significant, while acetylcholine, atropine, and
                                                                                                 epinephrine (p-values = 0.484, 0.377, 0.804 respectively)
           to that of serotonin. A regression analysis of                                        were not found to have a statistical significance. Note:
                                                                                                 amplitude is in units of N*1000. The trends are not linear,
                                                                                                 so why the linear fit? I still don’t understand your statistics.
           the unknown against the other five

           neurotransmitters eliminated acetylcholine and epinephrine because their regression coefficients

           were statistically different from the unknown’s (p-values p= 0.000 and 0.010, respectively). For

           those coefficients that were not statistically different from the unknown (atropine,

           norepinephrine, and serotonin) we used the difference between regression coefficients of each

           known and the unknown. We used the smallest difference as the indicator of similarity. The

                                                                                            6
                                                                                Neurotransmitter effect on crop-gizzard contractility

                                                                                                     absolute values of regression
                                   0.15
                                                                                                     coefficient differences from the
  Frequency of Contractions (Hz)


                                   0.12
                                                                                                     analysis of contractile frequency

                                   0.09                                                              were 0.611 (atropine), 1.055

                                   0.06                                                              (norepinephrine), and 0.417

                                   0.03
                                                                                                     (serotonin). Similarly the absolute
                                                                                            Serotonin
                                                                                            Unknown values of regression coefficient
                                   0.00
                                      0.000   0.007     0.014   0.021   0.028   0.035
                                                      Dose (weight %)                                differences from the analysis of

maximum amplitude were 129.497 (atropine), 360.98 (norepinephrine), and 48.88 (serotonin).

Additionally, for the regression analysis of the unknown against serotonin, the p-value was the

highest (0.377) indicating that its slope is most similar to the unknown than the

neurotransmitters. Figures 3 and 4 allow for a better illustration of these results by isolating

serotonin and the unknown from 1 and 2 respectively.




  Figure 3: Isolation of serotonin and the unknown from Figure 1 indicates that the unknown is most
  similar to serotonin in frequency of contraction. The isolation of serotonin and the unknown from Figure 1,
  make it easier (WC) to visualize the similarity between the two.
                                                                                        7
                                                                          Neurotransmitter effect on crop-gizzard contractility




Figure 4: Isolation of serotonin and the unknown from Figure 2 indicates that the unknown is most
similar to serotonin in maximum contraction of amplitude. The isolation of serotonin and the unknown
from Figure 2, make it easier to visualize the similarity between the two. Note: amplitude is in units of N*1000.

FIGURES – 3/ 5 POINTS

                                                                                                 If you’re comparing slopes, then
                            20                                                                   you need to include a graph (can
                                                                                                 be panel b in a figure) to make it
                                                                                                 easier for the reader to compare.
    Maximum Amplitude (N)




                            15                                                                   This would be stronger than
                                                                                                 inclusion of figures 3 and 4 that,
                                                                                                 while isolating the data for easier
                            10                                                                   direct comparison, also removes
                                                                                                 comparison against other NTs.

                             5                                                                   Good figures (including tables)
                                                                                                 include:
                                                                                     Serotonin
                                                                                     Unknown
                             0
                                                                                                       o   Axes labeled with units
                             0.000      0.007     0.014   0.021   0.028     0.035
                                                                                                 1/1
                                                Dose (weight %)
                                                                                                     o Includes statistics
                                 appropriate for figure (Regression, t-test, etc) 0/1
           o                     Includes stat info in the figure caption 0.5/1 what tests did you run?
           o                     Descriptive title as the first part of a caption 1/1
           o                     Descriptive caption that provides sufficient information for complete understanding 0.5/1
           o                     Each figure should illustrate the main point for the conclusion 0.5/1
           o                     Descriptive labels of figure elements (if the figure is a table: headings)
           o                     Figure numbers, enumerated by order of occurrence in report
           o                     Logical insertions into the document, i.e. within one page of the first figure reference, at the
                                 top or bottom of the page


5: All elements of a good figure and a figure title and caption
4: Missing one of the elements of a good figure but descriptive caption is present
3: Missing two elements of a good figure or all elements of a good figure and missing a descriptive
caption, aka just a figure title or a partial caption.

                                                                                8
                                             Neurotransmitter effect on crop-gizzard contractility

2: Missing a figure caption
1: Missing three elements of a good figure or missing one element and missing a caption
0: Anything else, i.e. missing four elements of a good figure or missing two or more elements and
missing a caption




RESULTS – 3/3 POINTS



The results section will include observations that are insightful, detailed, and relevant. For this
module, the results should include all relevant data that allows the reader to draw own conclusions.


3: All results elements
2: Missing one results element or all results present, but are not insightful, detailed, and relevant.
1: Missing two results elements or one results element missing and remainder are not insightful,
detailed, and relevant.
0: Anything else, i.e. missing two or more results elements, &c.
0: Results from own group are not presented.




Discussion

        The earthworm digestive tract has dual, antagonistic innervation (Millott, 1943a) and can

be affected by neurotransmitters that either enhance or inhibit contractions. Acetylcholine

evokes an excitatory response, causing food to be propelled through the earthworm's gut. A

previous experiment has shown that increasing concentrations of acetylcholine increased the

frequency of contractions while changes in amplitude appear to be statistically unchanged (Gibbs

and DeGolier, 2008). Interestingly, atropine has been shown to counter the effects of

acetylcholine, but, by itself, it has been shown to exhibit a slight excitatory effect (Wu, 1938).

For acetylcholine, our data is consistent with the data of Gibbs and DeGolier (2008). However,

for atropine, our data indicate an inhibitory effect on the crop gizzard (with a decrease in

contractile frequency). Since atropine was tested after acetylcholine, our result may be due to

residual acetylcholine in the testing column interfering with atropine.



                                                     9
                                          Neurotransmitter effect on crop-gizzard contractility

       Epinephrine and norepinephrine share many similarities in their effects, both have

stimulatory effects on the body, such as increased heart rate. However, enough differences exist

between the two chemicals to induce different effects on the crop-gizzard. Previous experiments

indicate that norepinephrine has an excitatory effect on the crop-gizzard of an earthworm, while

epinephrine has been shown to have both an inhibitory and an excitatory response on the crop

gizzard. In one experiment, the crop-gizzard is described as having a different response r to

epinephrine, concentrations above 1:100,000 caused a decrease in activity and those below

induce an increase in activity (Wu, 1938). However, in a second experiment (Millott, 1943b),

epinephrine was shown to induce inhibition of the gut activity. In a more recent experiment by

Krajniak and Corely (2003), norepinephrine and epinephrine caused a dose-dependent increase

in contraction amplitude of the isolated crop-gizzard. The results of these previous experiments

conflict with one another. Data from our experiment indicates norepinephrine has a significant

effect on maximum contractile amplitude but not contractile frequency, which is consistent with

the results from Krajniak and Corely (2003). Our data and the data from previous experiments

are not consistent with one another. This inconsistency suggests that there may be one or more

confounding factors that have not been considered.

       Serotonin has an inhibitory effect that presumably occurs when the organism needs to

reduce its peristaltic activity to expend energy to other functions during life threatening

circumstances. In our study, increasing concentrations of serotonin inhibited both contractile

amplitude and frequency. Our data is consistent with results described from previous

investigations (Wu, 1938; Millott, 1943b; Krajniak and Klohr, 1999, 2001; Krajniak and Corely,

2003). The results showed that the unknown was most similar to serotonin. Eliminating

acetylcholine and epinephrine using a regression analysis of the unknown against the other five



                                                 10
                                            Neurotransmitter effect on crop-gizzard contractility

neurotransmitters had reliable statistical proof. However, the method used to distinguish

between the last three neurotransmitters was not ideal. Comparing regression coefficients was a

rough estimate of the similarity between slopes, and did not take into account variability in the y-

intercept.


DISCUSSION – 2/4 POINTS

A good discussion will:

    o   Address all results in reference to the hypothesis. Tighten up the hypothesis to be able to
        reference it.
    o   Discuss the findings in light of both expectations and findings of peers
    o   Discuss all errors encountered and unexpected results
    o   Discuss the limitations of the experimental findings. What are the limitations?
    o   Discuss implications for further research. What are they?


4: All discussion elements and elements are relevant and nontrivial
3: Missing one discussion element and elements are relevant and nontrivial
2: Missing two or more discussion elements and elements are relevant and nontrivial or all discussion
elements present but elements are irrelevant or trivial
1: Missing one discussion element and elements are irrelevant or trivial
0: Anything else, i.e. missing two or more discussion elements and elements are irrelevant or trivial




        In conclusion, the data presented in this study suggests that the neurotransmitters have

different effects from one another on smooth muscle (already known). Our data was generally

consistent with the literature results except for epinephrine. Throughout our literature review

revealed conflicting results among different groups of researchers (?) (Wu, 1938; Millott, 1943b;

Krajniak and Klohr, 1999, 2001; Krajniak and Corely, 2003). This raises the intriguing

possibility that an unknown factor may be influencing the experimental values. Further testing

must be done to draw a valid result of the effects of epinephrine on smooth muscle.


CONCLUSION – 0.5/1 POINT




                                                   11
                                             Neurotransmitter effect on crop-gizzard contractility


fluff conclusion. Doesn’t really tell me much.

1: Relevant conclusion that links experimental findings (i.e. results of hypothesis testing) to greater
importance
0: Irrelevant conclusion or relevant conclusion without a link to greater importance




References

Guyton ACH, John E. Textbook of Medical Physiology: Elsevier Inc.; 2006.
Gibbs, S. DeGolier, T. 2008. Neurotensin and cholecystokinin depress motility in isolated
       Lumbricus terrestris crop-gizzard preparations. Comparative Biochemistry and
       Physiology, Part A 151, 682–686.

Krajniak, K., Corely, C. Southern Illinois Univ. Edwardsville: Effects of Alpha and Beta
       Adrenergic Agonists on the Earthworm Crop-gizzard. 2003.

Krajniak, K., Klohr, R., 1999. The effects of FMRFamide, serotonin, and acetylcholine on the
       isolated crop-gizzard of the earthworm, Lumbricus terrestris. Comp. Biochem Physiol. A
       123, 409–415.

Klohr, KG, & Krajniak, RW. (2001). The Use of an Isolated Earthworm Crop-Gizzard
       Preparation as a Model for Teaching Smooth Muscle Physiology. The American Biology
       Teacher, 63(1), 59.

Millott, N., 1943a. The visceral nervous system of the earthworm. I. Nerves controlling the tone
        of the alimentary canal. Proc. Roy. Soc. 131B, 271–295.

Millott, N., 1943b. The visceral nervous system of the earthworm. II. Evidence of chemical
        transmission and the action of sympatheticomimetic and parasympatheticomimetic drugs
        on the tone of the alimentary canal. Proc. Roy. Soc. 131B, 362–373.

Wu, K.S., 1938. On the physiology and pharmacology of the earthworm gut. J. Exp. Biol. 16,
      184–197.


STYLE GUIDELINES
SPELLING – 0.1/0.1


                                                    12
                                             Neurotransmitter effect on crop-gizzard contractility

Spelling is technical: both word choice (e.g. their v. they’re) and plurality (e.g. use of plural instead of
singular) are covered in the grammar section


0.10: No more than 1 spelling error
0.05: No more than 4 spelling errors
0.00: More than 4 spelling errors

GRAMMAR – 0.1/0.1

0.10: Good grammar. The basics of grammar are upheld, with no more than 3 occurrences errors:

    o   Word choice is correct (both homonym-type, e.g. their v. they’re, and technical-type, e.g.
        however v. nevertheless)
    o   Subject/verb agreement is correct
    o   Possessive use is correct
    o   The word “this” is followed by a subject
    o   Appropriate use of punctuation marks (particularly with respect to `comma-happiness’)
    o   Scientific names are correctly capitalized and italicized
    o   Other grammatical foibles, if infrequent and not so severe as to distort the meaning of the
        report, are forgivable.


0.05: Passable grammar. One or more of the list above have been violated more than 3 times, but the
violations are not so severe as to mar the readability or meaning of the report.
0.00: Poor grammar. Frequent grammar errors of the above list have marred the readability or the
meaning of the report.

STRUCTURE – 0.1/0.1

A paragraph is a `thought unit’, which includes:

    o   Topic sentence
    o   Supporting sentences, one or more
    o   Conclusion sentence

There is a 10 page hard limit for the report, not including citations or the cover page.
0.10: Report is structured in paragraphs, one paragraph per idea, with logical flow from one thought to
the next and the report is under the page limit
0.05: Report is structured in paragraphs but there are multiple unrelated ideas per paragraph or flow is
poor from one thought to the next and the report is under the page limit
0.00: Report is not structured in paragraphs or the report exceeds the page limit

CITATIONS – 0.1/0.1

`Almost always’ appropriate citations sources include:

    o   Peer-reviewed journals
    o   Patents
    o   Technical documentation (e.g. Sigma-Aldrich, Invitrogen)
    o   Technical books (e.g. a text book – used sparingly)
    o   Government documentation (e.g. NIST, CDC)


                                                    13
                                            Neurotransmitter effect on crop-gizzard contractility

    o   Personal communication from an authority (used sparingly)

`Almost always’ inappropriate citation sources include:

    o   Wikipedia or other encyclopedias
    o   Personal web sites
    o   Scientific rags (e.g. Popular Science or Scientific American)

In general, appropriate citation sources are primary sources that can be verified, whereas
inappropriate citation sources are secondary sources or aggregated information or cannot be easily
verified. It might be acceptable to use an inappropriate citation source in the introduction of a paper,
for example, to show public interest in a problem area. The proper use of citation sources tends to
follow something like the Miller test, in this case, that the average technical person would find the
citation source to be appropriate and of merit.


0.10: Appropriate citations where necessary and citations are from appropriate sources
0.05: Citations are present, but more should be used and citations are from appropriate sources
0.00: Citations missing or 1 or more citations are inappropriate (including and especially Wikipedia)

READABILITY – 0.05/0.1

I had to really search for clues of how you were determining the unknown/doing your analysis of
statistics.

A subjective score of the ease of reading the report. “Readability” is a general assessment of the
organization, topics covered in the report, and the general `flow’. Specific issues with a report are
graded according to the individual sections. There are some elements that greatly influence
readability:

    o   Use of language that is simple, direct, economic and familiar
    o   Omission of needless words
    o   Use of sentence structures that are evident and unambiguous
    o   Organization and structure of material in an orderly and logical way


0.10: The report is well-written, concise, lucid, and enjoyable to read
0.05: The report is clear, but not completely enjoyable to read, perhaps due to minor infractions of the
above list
0.00: The report is painful to read in one sitting, perhaps due to more severe or numerous infractions
of the above list




                                                   14

				
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