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To describe results use tentative verbs and modals:
It appears/seems/ is likely/ that …
These results suggest …
It is possible that …;
Use past tense.
TASKS:
1. How long did it take you to write the body of the paper? What was the
most difficult thing about it?
2. Read the list of phrases and choose the most appropriate ones to finish
your paper.
List of phrases to write the conclusion/discussion section
1. This research has attempted to … .
2. The original assumption was that … .
3. The findings of … suggest that … is appropriate to … .
4. Analogous results hold for … .
5. One reason could be that … .
6. These results could be explained by assuming that … .
7. It is unlikely that … .
8. These findings suggest/imply/provide evidence that … .
9. Detailed understanding of … is still lacking … .
10. The method becomes even more efficient for the … case.
11. From a computational viewpoint … .
12. In this context these results are the same as those obtained from the …
method.
13. The methods described here have more general application … .
14. It was observed that … does not have a significant effect on the
performance of the … equations.
15. The principal results and findings are as follows … .
16. Analyses of experimental data obtained during … demonstrate that the
inverse procedure is capable of accurately predicting … over significant
periods of time.
17. The results from … were compared with results from … .
18. The model will be useful in the analysis of … processes.
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19. A significant advantage of this theory is that … .
20. It should be noted that the results recorded here are rather preliminary.
21. Finally, an important conclusion follows from … .
22. It is a logical consequence of the fact that … .
23. It would be interesting to … .
24. Much further research is needed in the area of … .
TASK 1: Read the following recommendation which will help you avoid
certain mistakes while writing the conclusion of your paper.
Avoid:
– afterthoughts or additional ideas - now is the time to end the paper, not to
begin a new thought
– the use of “thus,” “in conclusion,” or “finally” at the beginning of the
last paragraph. Readers can see plainly the end of the paper.
– ending the paper without a sense of closure.
– questions that raise new issues; however, rhetorical questions that restate
the issues are acceptable.
TASK 2: Read samples 3–5 and notice how to write the “Discussion of
Results”, “Conclusion” and “Acknowledgements’ parts of a
research paper.
Sample 3
Results and Discussion
A complex mixture of products results from the reaction of a methanolic
solution of ammonia with artemisinin as determined by TLC. A 1H NMR
spectrum of the mixture suggested the presence of a methyl ketone, but no
signal characteristic of an aldehydic proton was observed. Apparently the
amide nitrogen or hydroperoxide moieties form adducts with the aldehyde
(e.g. 3c,d, respectively, in Scheme 1).
Prolonged reaction of 2 and ammonia produces a more complex mixture
containing polar products. Avery et al.4 synthesized several artemisinin
derivatives by treating crude mixtures of hydroperoxides with acid. They
employed Amberlyst 15 in their early work4b but in later publications
reported superior yields with a mixture of aqueous sulfuric acid/silica gel
(H 2SO4 /SiO2).
4c
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Treatment of the crude reaction mixture from 2 and ammonia with H2SO
/ SiO2, as described by Avery et al.,4c produced a mixture of two products
separable by column chromatography.5 The major product, 11-azaartemisinin
(4), was obtained in 45 % yield and a more polar product, 10-azadesoxyartemisinin
(5), in 9 % yield. The structural assignments of 4 and 5 were based on 1H
and 13C NMR and mass spectrometric data. When Amberlyst 15 was substituted
for H2SCO4 / SiO2, the yield of 4 increased to 65 % and compound 5 was
not observed.
The conversion of artemisinin into a lactam led us to attempt to prepare
N-substituted 11-azaartemisinins using alkylamines instead of ammonia. The
reaction of a methanolic solution of allylamine with 2 produced a mixture
of products which on treatment with dilute H2SO4/SiO2 yielded N-allyl-11azaartemisinin, 6, in 45 % yield along with N-allyl-10-azadesoxyartemisinin,
7, in 15 % yield.
Reaction of 2 with aromatic and heteroaromatic amines was also
examined. In order to obtain N-substituted 11-azaartemisinins, it proved
essential to remove any unreacted amine present in the reaction mixture
prior to treatment with acid. Failure to do so resulted in formation of Nsubstituted 10-azadesoxy-artemisinins. Volatile amines could be removed
in vacuo, whereas the less volatile amines required extraction of a methylene
chloride solution of the crude reaction mixture with an aqueous citrate buffer
(pH 4.5) Freshly distilled benzylamine and 2 with the modified workup
yielded 13. Reaction of 2 with the heterocyclic amines, 2-(aminomethyl)
pyridine, 2-(aminomethyl)-thiophene, and 2-(aminomethyl)furan, followed
by acid treatment yielded compounds 14–16.
In exploring the use of 11-azaartemisinins as potential intermediates
for the preparation of antimalarial drugs, several reactions of 4 and 6 were
investigated. Reaction of compound 4 with allyl bromide in the presence of
silver oxide yielded a compound isomeric with 6. Its structure has been
assigned as that of the O-allyl derivative 12 based on an analysis of its 1H
and 13C NMR spectra, mass spectrometric data, and the known reactivity of
amides with alkyl halides in the presence of base.6 Ozonolysis of the double
bond in 6 yielded aldehyde 17.
The above N-substituted 11-azaartemisinins were screened against a
chloroquine-resistant strain (FCR3) of P. falciparum using a previously
published8 modification of the method of Desjardins et al.9 The in vitro test
results are summarized in Table 1 and demonstrate that replacement of the
lactone moiety of 2 by a lactam, as in 4, yields an antimalarial drug with
53
4
equivalent biological activity. The antimalarial activities of 8, 14, and 17
were 1 order of magnitude greater than that of artemisinin. These findings
are consistent with those found by Avery et al.4a for their desmethylartemisinin
derivatives, i.e., the antimalarial activities of lactams were as great as or
greater than that of artemisinin. The presence of the endoperoxide for
antimalarial activity was essential as with other artemisinin derivatives; 3a the
oxides possess no significant anti-malarial activity. Although additional data
are needed for a precise comparison of the relative in vitro activities of 17
and 2, we proceeded to prepare sufficient quantities of 17 for in vivo testing.
The in vivo test data are given in Table 2, which shows that 17 is at least 4
times more active than 2; i.e., it is approximately as active as в-arteether.
Neither recent clinical trials
2a,b,d,e
nor earlier clinical studies in China
found artemisinin derivatives to be toxic. However, reports by Brewer et al.
indicate that repeated administration of в-arteether, 1b, produces neurotoxic
reactions in animals. In evaluating the potential of 17 as an antimalarial
drug, data on its toxicity and bioavailability will be required. Additional
azaartemisinin derivatives will be prepared as part of our planned structure –
activity relationship (SAR) studies.
Sample 4
Conclusions
Conversion of the lactone moiety of artemisinin into a lactam does not
reduce its biological activity. Two N-substituted 11-azaartemisinins were
found to exhibit enhanced in vitro antimalarial activity compared to 2. In
vivo test data show that the lactam 17 is ca. 4 times more active than 2 and
as potent as в-arteether. Replacement of the endoperoxide moiety in
11-azaartemisinins by an oxide results in loss of antimalarial activity. The
in vitro and in vivo activities of N-substituted azaartemisinins indicate that
additional derivatives should be prepared and studied.
2c
7
Sample 5
Acknowledgements
1. We appreciate helpful discussions with Prof. A. and Dr. B.
2. I thank Mr. C and Mr. D for supportive comments, constructive suggestions
and discussions.
3. This work was supported by the DOE under Grant No … .
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4. The author is grateful for Grant No … from … .
5. The authors wish to express their sincere thanks to Dr. X. and Dr. Y. for
their invaluable assistance in … , and for their penetrating criticism.
TASK: Decide what techniques the authors use to finish their paper. What
do you like/dislike about it?
Unit 4. Proofreading the paper
When typing the final manuscript, pay special attention to the format
and layout of your paper (margins, spacing, arrangement of the text, etc.)
and then proofread it. Read the paper several times to detect and correct all
possible types of errors. A computer can be very helpful with checking the
spelling, grammar, and style.
Double-check in-text citations to be certain that each one is correct and
that each source is listed in the “Works Cited” or “References” page at the
end of the paper.
TASK: Proofread your paper and ask your fellow-students to do the same.
What errors have you/ your fellow-students noticed? What
techniques did you use?
Unit 5. Acknowledging Sources
Having written your paper, you should list the reference materials used
to give credit to those sources, and to enable readers to consult the sources
for further information. You can label this page “Works/ Sources Cited”,
“Bibliography”, or “References” depending on the character of items
included – all works related to the subject or only those quoted; printed
works as well as nonprint items, e.g., speeches. Although there is no
universally agreed-upon system for acknowledging sources, first, write down
name of author, next, title of publication, and then publication source, date,
and page. Alphabetize the entries according to the author’s last name, e.g.
References
[1 ] Alin, M. H., Ashton, M., Bjorkman, A. In vitro activity of artemisinin,
its erivatives, and pyronari-dine against different strains of Plasmodium
falciparum. Tmia R. Soc. Trop. Med. Hyg. 1990, 84, 635-637.
55
[2] WHO.Tenth Programme Report of UNDP/World Bank/WHO Special
Programme for Research and Training in Tropical Diseases. WHO:
Geneva, 1991; p 30.
[3] ……………………………………………………………..
TASK: Look through the “References” pages in the journals on the subject
of your research and write a reference page of your paper.
Unit 6. AN ABSTRACT
An abstract is a brief description of the paper. It summarizes the basic
ideas developed in the paper. The abstract, as well as the title, helps readers
decide to read or to skip the paper. Therefore, it should be accurate, concise,
specific, objective and self-contained.
As a rule, the abstract is placed at the beginning of the paper, below the
title. It is written last, when the final version of the paper is produced.
Providing an abstract in English will give your work a much higher
profile outside your own country and make it much more accessible to
international workers in the same field.
There are two types of abstracts: informational and descriptive.
Informational Abstracts, which usually follow a similar order to a
scientific paper:
1. Provide communicative contents of reports.
2. Include purpose, methods, scope, results, conclusions, and
recommendations.
3. Highlight essential points.
4. Are short – from a paragraph to a page or two, depending upon the
length of the report (10 % or less of the report).
5. Allow readers to decide whether they want to read the report.
Descriptive Abstracts, which describe the publication itself (e.g.
surveys, review articles, book chapters, etc.), rather than report particular
findings:
1. Tell what the report contains.
2. Include purpose, methods, scope, but not results, conclusions, and
recommendations.
3. Are always very short – usually less than 100 words.
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4. Introduce subject to the readers, who must then read the report to
learn/study results.
TASK 1: Read sample 6. What king of an abstract is it?
Sample 6
ABSTRACT
Syntheses and Antimalarial Activities
of N-Substituted 11-Azaartemisinins
Daniel S. Torok and Herman Ziffer*
National Institutes of Health, Building 5, Bl-31, Bethesda, Maryland 20892-0510
Steven R. Meshnick and Xing-Qing Pan
Department of Epidemiology, University of Michigan School of Public Health,
Ann Arbor, Michigan 48109-2029
Arba Ager
University of Miami School of Medicine, Center for Tropical Parasitic Diseases,
Department of Microbiology and Immunology, 12500 S. W. 152nd Street, Miami,
Florida 33177
A two-step reaction sequence between artemisinin and methanolic
ammonia followed by treatment with Amberlyst 15 yielded 11-azaartemisinin
in 65 % yield. Substituting a variety of primary alkyl- and heteroaromatic
amines for ammonia in the reaction sequence yields N-substituted 11azaartemisinins in similar or greater yield. When Amberlyst 15 is replaced
by a mixture of sulfuric acid/silica gel, both 11-azaartemisinin and the
expected metabolite, 10-azadesoxyartemisinin, are formed in 45 % and 15 %
yields, respectively. In vitro and in vivo test data for a number of novel N-
substituted 11-azaartemisinins, against drug-resistant strains of Plasmodium
falciparum, show they possess antimalarial activities equal to or greater
than that of artemisinin. The most active derivative, N-(2'-acetaldehydo)11-azaartemisinin, 17, was 26 times more active in vitro and 4 times more
active in vivo than artemisinin.
TASK 2: Whichever type of abstract you write, follow the recommendations
given below:
– do not repeat the information given in the title;
– do not include in the abstract any facts or ideas that are not in the text;
eliminate unnecessary background information;
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– decide the degree of detail you include (especially for informational
abstracts);
– use direct, straightforward English; reduce wordy phrases; avoid jargon;
– use the past tense when describing what was done;
– finally, revise the opening statement to emphasize the new information
contained in the paper.
What strategies to write an abstract do you find most helpful? Which ones
are you going to use?
TASK 3: Read the list of phrases and choose the most appropriate ones to
write the abstract of your paper.
List of phrases to write an abstract
1. A quantitative model is presented … .
2. It is shown that … effects are … .
3. The present model shows that … .
4. An upper bound of …between … and … is established for … .
5. By examining inherent structures for … it becomes clear that … .
6. … are shown to have higher/lower indices than … to exceed conventional
bounds.
7. … were observed and studied under … conditions.
TASK 4: Now write the abstract of your research paper.
COMMUNICATIVE PRACTICE
Discuss the topic for a new paper with your thesis advisor. Follow
recommendations you have learnt in Unit 3. Write a paper and an abstract
to it.
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MODULE 4. WRITING LETTERS
Unit 1. Letter Layout
There are some important parts in a typical standard letter: the sender’s
address, date, the recipient’s address, salutation, the subject (optional), the
body of the letter, complimentary close, signature, the name and the title of
the sender, enclosure (optional).
The Heading or the Letterhead (the return address/the sender’s
address) is usually placed in the top right-hand corner of the page. It bears
all the necessary information about the sender: the name and address of the
institution, organization’s identity, position, title and address of the sender,
the telephone, telex, fax numbers, e-mail or any other details that may be
required, such as reference numbers, codes, etc.
To avoid difficulties in writing Russian names and surnames the following
information may be of use:
ё – io, yo, ie: Semionov, Semyonov, Semienov;
ж –- zh: Zhukov;
з – z, s: Kuznetsov, Vosnesenskiy;
й – ei, iy: Aliseichik, Bykovskiy;
х – kh, h: Malakhov; Astahov;
ц – ts: Tsvetkov;
ч – ch: Chugunov;
ш – sh: Timoshenko;
щ – sch: Paschenko;
ы – y: Bykov;
ь – ‘: Belen’kiy;
ю – yu, iu: Yurkov, Mavliukov;
я – ja, ya: Slepian, Yakovlev.
The Date should be placed below the sender’s address usually one or
two spaces lower. The date may be written as month-day-year (US style)
11/06/2010 or day-month-year (UK style) 06.11.2010 and the year written
with all four digits. A comma should be put between the day of the month,
and the year to separate the numerals and prevent confusion November 6th,
2010.
59
The Inside Address (the recipient’s address) is always on the left
margin, two spaces below the date. It includes the recipient’s name, job
title, address and postal (zip) code or zone number.
The initials of the first name are placed in front of the surname.
The words street, road or avenue may be abbreviated: St., Rd., Ave., .
The postal (zip) code or zone number is a geographical abbreviation.
Be sure to put it in all addresses in countries that use it. In the United States
the zip code uses five numbers; some countries use numbers and letters.
The Salutation (the greeting) begins two spaces below the receiver’s
address and is written with the margin on the left. In Great Britain the salutation
is followed by a comma (Dear Sir,), in the USA – by a colon only in formal
letters (Dear Sir:). The salutation is never followed by an exclamation mark
or by a dash only.
The type of salutation depends on your relationship with the recipient, the
purpose of the letter, the position that your correspondent holds. It normally
begins with the word “Dear” and always includes the person’s last name.
A title, such as Prof. or Dr. is used only with the surname.
In writing letters the following salutations are used:
A. formal salutations:
– Dear Sir
– Dear Madam /Dear Ms. (If the letter-writer is not sure whether the
lady is married or unmarried)
B. less formal salutations:
– Dear Mr. Smith
– Dear Mrs. Smith (to married woman.)
– Dear Miss Smith (to unmarried woman.)
– Dear Dr. Smith
– Dear Prof. Smith
– Dear Colleagues
The Subject (optional) can help the recipient in dealing successfully
with the aims of your letter. Subject line may be emphasized by underlining,
using bold font, or all capital letters. It is usually placed one line below the
greeting but alternatively can be located directly after the “inside address,”
before the “greeting.”
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