1. Scientific Writing, HRP 214 Weekly Quiz

2. Scientific Writing, HRP 214 A. We studied the affects of the gene on signaling. B. We studied the effects of the gene on signaling.

3. Scientific Writing, HRP 214 A. We studied the affects of the gene on signaling. B. We studied the effects of the gene on signaling.

4. Scientific Writing, HRP 214 A. She commented on the clearly defined mutant traits. B. She commented on the clearly-defined mutant traits.

5. Scientific Writing, HRP 214 A. She commented on the clearly defined mutant traits. B. She commented on the clearly-defined mutant traits.

6. Scientific Writing, HRP 214 A. I like books, chocolate, and coffee. B. I like books, chocolate and coffee.

7. Scientific Writing, HRP 214 A. I like books, chocolate, and coffee. B. I like books, chocolate and coffee.

8. Scientific Writing, HRP 214 A. She was self-employed. B. She was self employed.

9. Scientific Writing, HRP 214 A. She was self-employed. B. She was self employed.

10. Scientific Writing, HRP 214 A. 65 people were saved. B. Sixty-five people were saved.

11. Scientific Writing, HRP 214 A. 65 people were saved. B. Sixty-five people were saved.

12. Scientific Writing, HRP 214 A. She was the best-read scientist in the lab. B. She was the best read scientist in the lab.

13. Scientific Writing, HRP 214 A. She was the best-read scientist in the lab. B. She was the best read scientist in the lab.

14. Scientific Writing, HRP 214 A. The previously-reported data were suspect. B. The previously reported data were suspect.

15. Scientific Writing, HRP 214 A. The previously-reported data were suspect. B. The previously reported data were suspect.

16. Scientific Writing, HRP 214 A. That was pre-SARS. B. That was pre SARS.

17. Scientific Writing, HRP 214 A. That was pre-SARS. B. That was pre SARS.

18. Scientific Writing, HRP 214 A. He cited the widely-believed fallacy. B. He cited the widely believed fallacy.

19. Scientific Writing, HRP 214 A. He cited the widely-believed fallacy. B. He cited the widely believed fallacy.

20. Scientific Writing, HRP 214 A. She was a well-known scientist. B. She was a well known scientist.

21. Scientific Writing, HRP 214 A. She was a well-known scientist. B. She was a well known scientist.

22. Scientific Writing, HRP 214 A. She was well-known. B. She was well known.

23. Scientific Writing, HRP 214 A. She was well-known. B. She was well known.

24. Scientific Writing, HRP 214 A. He counted six pies. B. He counted 6 pies.

25. Scientific Writing, HRP 214 six A. He counted six pies. B. B. He counted 6 pies.

26. Scientific Writing, HRP 214 A. His favorite breakfasts were cinnamon oatmeal, French toast, and ham and eggs. B. His favorite breakfasts were cinnamon oatmeal, French toast, ham, and eggs.

27. Scientific Writing, HRP 214, and ham and eggs. A. His favorite breakfasts were cinnamon oatmeal, French toast, and ham and eggs. B. His favorite breakfasts were cinnamon oatmeal, French toast, ham, and eggs.

28. Scientific Writing, HRP 214 A. Many of the clinic’s patients die from complications of diabetes. B. Many of the clinic’s patients die of complications of diabetes.

29. Scientific Writing, HRP 214 A. Many of the clinic’s patients die from complications of diabetes. B. Many of the clinic’s patients die of complications of diabetes   understanding mnemonic: die (as a result) of  IEO  word pattern mnemonic: dIE Of

30. Scientific Writing, HRP 214 Lecture Six: Methods and Materials, Results, Tables and Figures

31. Scientific Writing, HRP 214 Scientific Manuscripts Scientific Manuscripts (original research)

32. Scientific Writing, HRP 214 Scientific Manuscripts: outline Title Authorship Abstract Introduction Materials and Methods Results (includes figures and tables) Discussion Acknowledgements References

33. Scientific Writing, HRP 214 Methods Materials and Methods

34. Scientific Writing, HRP 214 Methods and Materials Materials and Methods Overview: Give a clear overview of what was done Give enough information to replicate the study (like a recipe!) Be complete, but minimize complexity! 1.Break into smaller sections with subheads 2.Cite a reference for commonly used methods 3.Display in a flow diagram where possible You may use jargon and the passive voice more liberally in the M&M section

35. Scientific Writing, HRP 214 Materials Materials Drugs generic name, manufacturer, purity, concentration, amount administered, etc. Culture media, buffers components and concentrations, temperature, pH Experimental materials cell line, molecule, tissue, etc. Animals state that the research was approved by the appropriate committee at your institution Human subjects state that the research was approved by the appropriate committee at your institution

36. Scientific Writing, HRP 214 Materials e.g., Human subjects “ Details of the study and testing procedures were explained to each subject, and a written, informed consent was obtained. The experimental protocol was approved by the Institutional Review Boards of Stanford University, the University of California, Los Angeles, the University of Michigan, the Helen Hayes Hospital, and Massachusetts General Hospital.”

37. Scientific Writing, HRP 214 Methods Materials and Methods Overview: Be complete, but minimize complexity! 1.Break into smaller sections with subheads 2.Cite a reference for commonly used methods 3.Display in a flow diagram where possible

38. Scientific Writing, HRP 214 Methods 1. Break into sub-sections with informative subheadings

39. Scientific Writing, HRP 214 Methods e.g., Ksiazek et al. A Novel Coronavirus Associated with Severe Acute Respiratory Syndrome NEJM 348:1953-1966, May 15, 2003 METHODS General Approach Biosafety Isolation of Virus Serologic Analysis Pathological and Immunohistochemical Studies Molecular Analyses

40. Scientific Writing, HRP 214 Methods e.g. Jonsson et al. Fibroblast Growth Factor 23 in Oncogenic Osteomalacia and X-Linked Hypophosphatemia NEJM 348:1656-1663; April 24, 2003. METHODS Peptide Synthesis and Antibody Production Generation of Recombinant FGF-23 Development of an ELISA for the Detection of FGF-23 Study Subjects

41. Scientific Writing, HRP 214 Methods The Journal of Cell Biology, Volume 161, Number 3, 521-533 Proprotein convertase cleavage liberates a fibrillogenic fragment of a resident glycoprotein to initiate melanosome biogenesis Joanne F. Berson 1, Alexander C. Theos 1, Dawn C. Harper 1, Danielle Tenza 2, Graça Raposo 2 and Michael S. Marks 1 Methods and materials Cell culture and transfections Antibodies Plasmids Recombinant virus production and infection Metabolic labeling and immunoprecipitation Immunoblotting Subcellular fractionation Electron microscopy

42. Scientific Writing, HRP 214 Methods For clinical studies: 1.Study design 2.Setting 3.Patients/subjects 4.Interventions or predictors (independent variables) 5.Primary outcome (dependent variable) 6.Secondary outcomes 7.Statistical analysis 8.Sample size and power calculations, if available

43. Scientific Writing, HRP 214 Methods Subsections for a clinical study: Study design randomized trial, prospective cohort, case-control, case-series etc. Setting clinic, hospital, or general population locations Participants eligibility criteria (inclusion, exclusion) Independent variables how were predictors measured or interventions assigned and administered? Primary outcomes case definitions/measurement Secondary outcomes

44. Scientific Writing, HRP 214 Methods Statistical aspects Sample size How sample size was determined Explanation of any interim analyses and stopping rules. Statistical methods Statistical methods used to compare groups for primary outcome(s); Methods for additional analyses, such as subgroup analyses and adjusted analyses.

45. Scientific Writing, HRP 214 Additionally, for a Randomized Clinical Trial: Randomization Scheme Sequence generation Method used to generate the random allocation Details of any restriction (e.g., blocking, stratification). Allocation concealment Method used to implement the random allocation sequence Was the sequence was concealed until assignment of interventions? Implementation Who generated the allocation sequence? Who enrolled participants? Who assigned participants to their groups? Blinding (masking) Were participants, those administering the interventions, and those assessing the outcomes blinded to group assignment? Was the success of blinding evaluated?

46. Scientific Writing, HRP 214 Methods 2. Cite a reference for commonly used methods or previously used methods rather than explaining all the details…

47. Scientific Writing, HRP 214 Methods Each peptide was covalently coupled to agarose (AminoLink Kit, Pierce Chemical), and 30-to-200-ml quantities of each crude polyclonal antiserum were affinity-purified with the use of the appropriate immobilized peptide, as previously described. 13 13 Immunoprecipitations, SDS-PAGE on 10% polyacrylamide gels, and phosphorimaging analysis were performed as described previously (Berson et al., 2000).Berson et al., 2000

48. Scientific Writing, HRP 214 Methods 3.Use flow diagrams to help simplify explanations of methods!

50. From: Oral topiramate for treatment of alcohol dependence: a randomised controlled trial Johnson et al. The Lancet. Volume 361;17 May 2003

51. WeekMorning doseAfternoon doseTotal daily dose 10 mg1x25 mg tablet25 mg 20 mg2x25 mg tablets50 mg 31x25 mg tablet2x25 mg tablets75 mg 42x25 mg tablets 100 mg 52x25 mg tablets1x100 mg tablet150 mg 61x100 mg tablet 200 mg 71x100 mg tablet1x100 mg and 2x25 mg tablets250 mg 81x100 mg and 2x25 mg tablets 300 mg 91x100 mg and 2x25 mg tablets 300 mg 101x100 mg and 2x25 mg tablets 300 mg 111x100 mg and 2x25 mg tablets 300 mg 121x100 mg and 2x25 mg tablets 300 mg Schedule is similar to that provided in the Physicians' Desk Reference (2000). The placebo and topiramate groups received the same number of tablets; placebo tablets were inactive. Table 1: Topiramate dose-escalation schedule From: Oral topiramate for treatment of alcohol dependence: a randomised controlled trial Johnson et al. The Lancet. Volume 361;17 May 2003 Other tables and figures that can help illustrate methods:

52. Medicine & Science in Sports & Exercise 2003; 35(5):826-831 Copyright © 2003 Medicine & Science in Sports & Exercise. All rights reserved Published by Lippincott Williams & Wilkins

53. Methods Transcription of antisense RNA leading to gene silencing and methylation as a novel cause of human genetic disease Cristina Tufarelli et al. Nature Genetics - Published online: 5 May 2003, doi:10.1038/ng1157

54. Methods Transcription of antisense RNA leading to gene silencing and methylation as a novel cause of human genetic disease Cristina Tufarelli et al. Nature Genetics - Published online: 5 May 2003, doi:10.1038/ng1157

55. Report methods in past tense (“we measured”), But use present tense to describe how data are presented in the paper (“data are summarized as means  SD”) Writing methods: verb tenses

56. 1. Passive (point of view of the experiment): “Blood samples were drawn.” Passive voice, but emphasizes the method or variable 2. Active (point of view of the experimenter): “We drew blood samples.” Active voice, more lively, but sacrifices having the topic as the subject of the sentence Requires creativity to avoid starting every sentence with “we”: e.g., “Because the layers did not stick well, we processed them as small pellets.” “After fixing the surface layers, we then…” Writing methods: passive vs. active voice

57. For sequencing, amplicons were purified with ExoSAP-Codes. The partial nucleotide sequences of the polymerase gene were aligned with published coronavirus sequences, using CLUSTAL W for Unix (version 1.7). From: Ksiazek et al. A Novel Coronavirus Associated with Severe Acute Respiratory Syndrome NEJM 348:1953-1966, May 15, 2003 Writing methods: passive voice and jargon

58. Scientific Writing, HRP 214 Methods: passive voice Peptides were synthesized by the Biopolymer Core Facility, Massachusetts General Hospital, Boston. Peptides representing portions of the FGF-23 precursor — [Cys70]FGF-23(51–69)amide, [Tyr185] FGF-23(186–206)amide, [Tyr223]FGF-23(206–222)amide, and [Tyr224]FGF-23(225–244)amide — were coupled to keyhole limpet hemocyanin, emulsified with complete Freund's adjuvant, and used for subcutaneous immunization of eight goats (with approximately 100 µg per animal); each… From Jonsson et al. Fibroblast Growth Factor 23 in Oncogenic Osteomalacia and X-Linked Hypophosphatemia NEJM 348:1656-1663; April 24, 2003.

59. Scientific Writing, HRP 214 Results Results

60. Scientific Writing, HRP 214 Results Results are different from data! Results=the meaning of the data Most data belong in figures and tables

61. Scientific Writing, HRP 214 Results Results: Report results pertinent to the main question asked Summarize the data (big picture); report trends Cite figures or tables that present supporting data

62. Scientific Writing, HRP 214 Results Does it belong in the text or in a table or figure? *text is used to point out simple relationships and describe trends Examples: “Over the course of treatment, topiramate was significantly more effective than placebo at improving drinking outcomes on drinks per day, drinks per drinking day, percentage of heavy drinking days, percentage of days abstinent, and log plasma -glutamyl transferase ratio (table 3).” “The total suicide rate for Australian men and women did not change between 1991 and 2000 because marked decreases in older men and women (table 1) were offset by increases in younger adults, especially younger men. 7 ”1 7

63. Scientific Writing, HRP 214 Results Hints: Use subheadings Include negative and control results Give a clear idea of the magnitude of a response or a difference by reporting percent change or the percentage of difference rather than by quoting exact data Reserve the term “significant” for statistically significant Do not discuss rationale for statistical analyses

64. Scientific Writing, HRP 214 Writing Results: tense Use past tense, except to talk about how data are presented in the paper. e.g.: We found that… Women were more likely to… Men smoked more cigarettes than… BUT: Figure 1 shows… Table 1 displays… The data suggest

65. Scientific Writing, HRP 214 Writing Results: tense Example: Information was available for 7766 current cigarette smokers. Of these, 1216 (16%) were classified as hardcore smokers. Table 1 gives characteristics of all the smokers. The most striking difference was that hardcore smokers were about 10 years older on average and tended to be more dependent on tobacco. Significantly more hardcore smokers had manual occupations, lived in rented accommodation, and had completed their full time education by the age of 16 years. There was no difference by sex.Table 1 FROM: Jarvis et al. Prevalence of hardcore smoking in England, and associated attitudes and beliefs: cross sectional study BMJ 2003;326:1061 (17 May)

66. Scientific Writing, HRP 214 Writing Results: tense Use active voice: -more lively -since you can talk about the subjects of your experiments, “we” can be used sparingly while maintaining the active voice.

67. Scientific Writing, HRP 214 Writing Results: point of view Comparison with Californian estimates Using the same definition of hardcore smoking as adopted in the Californian study, we found a prevalence of 17% across all age groups and 19% among smokers aged 26 compared with a figure of 5% for this group in the US study. When we added the Californian requirement of 15 cigarettes a day to our criteria we found a prevalence of 10% among smokers aged 26, still twice the prevalence in California FROM: Jarvis et al. Prevalence of hardcore smoking in England, and associated attitudes and beliefs: cross sectional study BMJ 2003;326:1061 (17 May)

68. Scientific Writing, HRP 214 Writing Results: point of view Differences in attitudes and beliefs by level of dependence To test whether it was appropriate to exclude a measure of cigarette dependence from our criteria for defining hardcore smoking, we compared attitudes and beliefs by dependence in hardcore and other smokers (table 4). For most items, beliefs were similar in low and high dependence hardcore smokers but strikingly different from those of other smokers. For example, almost 60% of both low and high dependency non-hardcore smokers agreed that improved health would be a major benefit from quitting whereas among hardcore smokers only 27% of low dependency and 32% of high dependency smokers agreed. Similar differentiation in beliefs by hardcore smoking status, but not dependence level, emerged for other items, especially those related to health.table 4

69. Scientific Writing, HRP 214 Tables and Figures Tables and Figures

70. Scientific Writing, HRP 214 Tables and Figures Editors (and readers) look first (and maybe only) at titles, abstracts, and Tables and Figures! Like the abstract, figures and tables should stand alone and tell a complete story.

71. Scientific Writing, HRP 214 Tables Tables

72. Scientific Writing, HRP 214 Table Titles and Footnotes Titles: Identify the specific topic or point of the table Use the same key terms in the title, the column headings, and the text of the paper Keep it brief

73. Scientific Writing, HRP 214 Table Titles and Footnotes Footnotes: Use superscript symbols to identify footnotes, according to journal guidelines: A standard series is: *, †,‡,¶,#,**,††, etc. Use footnotes to explain statistically significant differences E.g., *p<.01 vs. control by ANOVA Use footnotes to explain experimental details or abbreviations E.g., EDI is the Eating Disorder Inventory (reference) Amenorrhea was defined as 0-3 periods per year

74. Scientific Writing, HRP 214 Table Formats Format: Model your tables from already published tables! Don’t re-invent the wheel!! Use three horizontal lines: one above the column headings, one below the column heading, and one below the data Use a short horizontal line to group subheadings under a heading Follow journal guidelines RE: roman or arabic numbers; centered or flush left table number, title, column, headings, and data; capital letters and italics; the placement of footnotes; the type of footnote symbols

75. Tables: baseline, descriptive data T able 1. Base-Line Characteristics of the Women Who Underwent Radical Mastectomy and Those Who Underwent Breast-Conserving Therapy. Veronesi et al. Twenty-Year Follow-up of a Randomized Study Comparing Breast-Conserving Surgery with Radical Mastectomy for Early Breast Cancer NEJM 347:1227-1232; October 17, 2002 Three horizontal lines

76. Tables: baseline, descriptive data Standard deviation n Women’s health Initiative, JAMA, 2002

77. TABLE 1. Clinical and biochemical characteristics of control subjects and patients with anorexia nervosa From: Stoving: J Clin Endocrinol Metab, Volume 84(6).June 1999.2056-2063

78. Tables: To illustrate a point…

79. From: nurses health study

80. Tables: to illustrate a point NEJM: Shain et al. 340 (2): 93, January 14, 1999

81. Scientific Writing, HRP 214 Figures Use the fewest figures and tables needed to tell the story Do not present the same data in both a figure and a table

82. Scientific Writing, HRP 214 Figures Three varieties of Figures: 1.Primary evidence electron micrographs, gels, photographs, etc. indicates data quality 2.Graphs line graphs, bar graphs, scatter plots, histograms, boxplots, etc. 3.Drawings and diagrams illustrate experimental set-up indicate flow of experiments or participants indicate relationships or cause and effect or a cycle give a hypothetical model

83. Scientific Writing, HRP 214 Figure Legends **Allows the figure to stand alone. Contains: 1. Brief title 2. Experimental details 3. Definitions of symbols or line/bar patterns 4. Statistical information

84. Scientific Writing, HRP 214 Figures: Primary Evidence

85. Transcription of antisense RNA leading to gene silencing and methylation as a novel cause of human genetic disease Cristina Tufarelli et al. Nature Genetics - Published online: 5 May 2003, doi:10.1038/ng1157

86. NEJM Zucca et al. 338 (12): 804, Figure 1 March 19, 1998 Figure 1. Histologic Patterns in the Evolution from Chronic Gastritis to Gastric Lymphoma.

87. Esposito, Paul W. MD. Trampoline Injuries. Clinical Orthopaedics & Related Research. 1(409):43-52, April 2003.

88. Scientific Writing, HRP 214 Figures Graphs line graphs scatter plots bar graphs individual-value bar graphs histograms box plots relative risks survival curves

89. Scientific Writing, HRP 214 Graphs Exercise: Which graphs work and why? Which graphs confuse and why? **Does the graph tell a simple story?

90. Scientific Writing, HRP 214 Figures Graphs line graphs *Used to show trends over time or age (can display group means or individuals)

91. Figure 3. Hypertension Prevalences in 6 European and 2 North American Countries, Men and Women Combined, by Age Group JAMA Vol. 289 No. 18, May 14, 2003

92. Figure 3. Effect of Weight Loss on Serum Leptin Concentrations and Expression of the ob Gene in Seven Obese Subjects, Expressed as a Percentage of the Initial Value. Considine et al. NEJM 334: 292; February 1, 1996

93. From: Oral topiramate for treatment of alcohol dependence: a randomised controlled trial Johnson et al. The Lancet. Volume 361;17 May 2003

94. Scientific Writing, HRP 214 Tables and Figures Figure 2: Change in self-reported drinking outcomes from baseline (week 0) by study week

95. Scientific Writing, HRP 214 Figures Graphs bar graphs *Used to compare groups at one time point *Tells a quick visual story

96. Scientific Writing, HRP 214 FIGURE 2- Relationship between BMC of the forearm/heel and time since menarche. *Significantly different than forearm BMC of group 1 (< 1 yr since menarche); BMCA: forearm BMC; BMCH: heel BMC. Medicine & Science in Sports & Exercise 2003; 35(5):720-729

97. Figures: bar graphs Figure 1. Bone mineral density of amenorrheic (gray bars) and eumenorrheic athletes (black bars). Asterisk indicates P<.01; error bars indicate SE. From: Rencken: JAMA, Volume 276(3).July 17, 1996.238-240

98. Comparison of the total loads accumulated in Tour and Vuelta. Phases I, II, and III are intensity phases below the ventilatory threshold (VT), between VT and the respiratory compensation point (RCP), and above RCP, respectively…. Medicine & Science in Sports & Exercise 2003; 35(5):872-878

99. Scientific Writing, HRP 214 Figures Graphs scatter plots *Used to show relationships between two variables (particularly linear correlation) *Allows reader to see individual data points=more information!

100. Figure 1. The Relation between the Percentage of Body Fat and the Serum Leptin Concentration in 136 Normal-Weight and 139 Obese Subjects. Considine et al. Serum Immunoreactive-Leptin Concentrations in Normal-Weight and Obese Humans NEJM 334: 292; February 1, 1996

101. Figure 2. Correlation between Expression of the ob Gene in Adipocytes and the Percentage of Body Fat in 27 Normal-Weight and 27 Obese Subjects. The data are expressed as the ratio of ob cDNA to actin cDNA. There was no difference in the amount of actin cDNA among the subjects studied. Considine et al. NEJM 334: 292; February 1, 1996

102. Fig. 4. Individual subject ApEn scores of GH secretion (m = 1; r = 20% sd) and cortisol secretion (m = 1; r = 80% sd) in normal weight women ([white four pointed star]) and in women with AN ([white diamond suit]). Horizontal lines represent the median values. *, P 0.05 (AN vs. controls). From: Stoving: J Clin Endocrinol Metab, Volume 84(6).June 1999.2056-2063

103. Scientific Writing, HRP 214 Figures Graphs survival curves Compares probability of failure (or survival) of two or more groups

104. Cumulative Hazard: WHI On hormones On placebo Hazard ratio = instantaneous rate ratio Nominal confidence interval Adjusted CI; adjusted for “multiple comparisons” Women’s health Initiative, JAMA, 2002

105. Scientific Writing, HRP 214 Figures Graphs Boxplots and histograms To show or compare data distributions

106. Box Plot maximum (163.9) interquartile range whisker 75th percentile (138.6) minimum (93.9) 25th percentile (115.5) median (127.0) A quartile = a quarter of the data x

107. Histogram Data are divided into 10- pound groups (called “bins”). With only one woman <100 lbs, this bin represents <1% of the total 120-women sampled. Percent of total that fall in the 10- pound interval. 85-95 95-105 105-115 115-125 125-135 135-145 145-155 155-165

108. Scientific Writing, HRP 214 Figures Graphs Confidence intervals/relative risks To show dose-response of a protective or harmful factor

109. Nurse’s Health Study

110. Drawings and Diagrams

111. Scientific Writing, HRP 214 Diagrams and Drawings Figure 2. Relation between altitude and inspired oxygen pressure From: Peacock: BMJ, Volume 317(7165).October 17, 1998.1063-1066

112. Scientific Writing, HRP 214 Diagrams and Drawings Figure 5. Effect of hypoxia on central nervous system From: Peacock: BMJ, Volume 317(7165).October 17, 1998.1063-1066

113. NEJM Talan et al. 340 (2): 85;January 14, 1999 Figure 1. Location of Wound Infections in 50 Patients Bitten by Dogs and 57 Patients Bitten by Cats.

114. Drawings: illustrate cause and effect/relationships Figure 2: Proposed pathways among disordered eating, menstrual irregularity, and low BMD. Solid lines represent associations suggested by the current study; dashed lines represent associations suggested by previous studies.

115. Figure 3. Model of the Difference in the Rate of Progression to AIDS between Patients with HLA-B*35-Px and Those with HLA-B*35-PY. Xiaojiang Gao Gao et al. Effect of a Single Amino Acid Change in MHC Class I Molecules on the Rate of Progression to AIDS NEJM 344:1668-1675; May 31, 2001

116. Figure 6. Possible origin of partially committed keratinocyte stem cells, and their specific association. We have demonstrated that the three concentric regions of the hair follicle (ORS, IRS, and shaft) originate from distinct progenitor cells. As discussed in the text, three possibilities can be envisaged for the origin of these cells: (A) they may derive from a totipotent keratinocyte stem cell that is still present and operative in the mature hair follicle; (B) they may derive from a totipotent progenitor cell during development, but exist as independent entities in the mature hair follicle; (C) they may be intrinsically the same, but become committed to differentiate along different pathways in response to stimuli from the local environment. For three progenitor cells to come together and originate a hair follicle, they must either interact specifically with each other (D), or use a specific anchoring mechanism, which could be provided by dermal papilla cells and/or their extracellular matrix (E). This latter mechanism could contribute to the hair-inducing capability of dermal papilla cells (DP), together with the likely, but as yet elusive release of hair- inducing growth factors (GF). From: Kamimura: J Invest Dermatol, Volume 109(4).October 1997.534-540

117. Scientific Writing, HRP 214 A few more (pseudo) homonyms and commonly confused words: 1a. ALLUDE v. ELUDE allude: to reference indirectly  She frequently alluded to her distrust of lawyers without explicitly stating her opinion.  He impressed the crowd with his allusions to Greek mythology. (n.b.: versus “illusion”) elude: to evade  The stealthy cat-burglar eluded the police all winter.  The elusive protein, which our team has been trying to characterize for months, has baffled labs across the country.

118. Scientific Writing, HRP 214 1b. ASSURE v. ENSURE v. INSURE assure: to promise, to state with confidence  She assured the students that no one would fail the course. ensure: to make certain  Well-planned interventions can ensure better outcomes for children with diabetes. insure: to protect against loss, in legal/financial realms  The post-docs could barely afford to insure their cars.

119. Scientific Writing, HRP 214 1c. ARRANT v. ERRANT arrant: being notoriously without moderation; extreme  We are arrant knaves, all; believe none of us. (Shakespeare) errant: given to travelling; straying outside the proper path or bounds; moving aimlessly or irregularly; deviating from a standard; fallible  The errant toddler found his way into all sorts of mischief.

120. Scientific Writing, HRP 214 2.AMONG v. BETWEEN Among: collective and undefined relations (three or more) You’re among friends. Agreement was reached among all four neighbors. Between: one-to-one relationships of pairs within a group or the sense “shared by.” Diplomatic relationships between the United States and France ceased. There is close friendship between the members of the club.

121. Scientific Writing, HRP 214 3.LAY v. LIE Lay is a transitive verb (takes an object) forms: lay, laid, has laid, is laying The hen lays an egg. (laid, had laid, is laying) “The best laid schemes o’ mice an’ men / Gang aft a-gley.” (“To a Mouse,” Robert Burns) Lie is an intransitive verb (does not take an object) forms: lie, lay, has lain, is lying The llama lies down.  Q: What about “Now I lay me down to sleep”???

122. Scientific Writing, HRP 214 4. DISINTERESTED v. UNINTERESTED Disinterested: impartial. Uninterested: not interested in. Let a disinterested person judge our dispute. This man is obviously uninterested in our dispute.

123. Scientific Writing, HRP 214 5.e.g. v. i.e. (informal) e.g. = “for example” from Latin: exempli gratia = ‘for the sake of an example’  Many animals (e.g., mountain lions, panthers, etc.) are quite good hunters. i.e. = “in other words” from Latin: id est = ‘that is’  That walking boot is synthetic (i.e., not leather or suede).

124. Scientific Writing, HRP 214 For next week Homework: Read chapter 3-4 of Successful Scientific Writing Edit peer’s letter to the editor—email to them by next Tuesday. 3-unit students: Tables & Figures, Results, Methods due next week (can be a “sketch” or in outline form)

125. Scientific Writing, HRP 214 For next week Next time… Abstracts, Introductions, Discussions