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1.  Evolutionary demography of iteroparous plants: incorporating non-lethal costs of reproduction into integral projection models 
Understanding the selective forces that shape reproductive strategies is a central goal of evolutionary ecology. Selection on the timing of reproduction is well studied in semelparous organisms because the cost of reproduction (death) can be easily incorporated into demographic models. Iteroparous organisms also exhibit delayed reproduction and experience reproductive costs, although these are not necessarily lethal. How non-lethal costs shape iteroparous life histories remains unresolved. We analysed long-term demographic data for the iteroparous orchid Orchis purpurea from two habitat types (light and shade). In both the habitats, flowering plants had lower growth rates and this cost was greater for smaller plants. We detected an additional growth cost of fruit production in the light habitat. We incorporated these non-lethal costs into integral projection models to identify the flowering size that maximizes fitness. In both habitats, observed flowering sizes were well predicted by the models. We also estimated optimal parameters for size-dependent flowering effort, but found a strong mismatch with the observed flower production. Our study highlights the role of context-dependent non-lethal reproductive costs as selective forces in the evolution of iteroparous life histories, and provides a novel and broadly applicable approach to studying the evolutionary demography of iteroparous organisms.
PMCID: PMC3367791  PMID: 22418255
cost of reproduction; delayed reproduction; demography; integral projection model; iteroparity; life-history evolution
2.  Anthrax Postexposure Prophylaxis in Postal Workers, Connecticut, 2001 
Emerging Infectious Diseases  2002;8(10):1133-1137.
After inhalational anthrax was diagnosed in a Connecticut woman on November 20, 2001, postexposure prophylaxis was recommended for postal workers at the regional mail facility serving the patient’s area. Although environmental testing at the facility yielded negative results, subsequent testing confirmed the presence of Bacillus anthracis. We distributed questionnaires to 100 randomly selected postal workers within 20 days of initial prophylaxis. Ninety-four workers obtained antibiotics, 68 of whom started postexposure prophylaxis and 21 discontinued. Postal workers who stopped or never started taking prophylaxis cited as reasons disbelief regarding anthrax exposure, problems with adverse events, and initial reports of negative cultures. Postal workers with adverse events reported predominant symptoms of gastrointestinal distress and headache. The influence of these concerns on adherence suggests that communication about risks of acquiring anthrax, education about adverse events, and careful management of adverse events are essential elements in increasing adherence.
PMCID: PMC2730305  PMID: 12396928
Anthrax; Bacillus anthracis; prophylaxis; adverse effects; ciprofloxacin; doxycycline; patient noncompliance; Connecticut
3.  Acute abdominal pain presenting as a rare appendiceal duplication: a case report 
Appendiceal duplication is a rare anomaly that can manifest as right lower quadrant pain. There are several variations described for this condition. We recommend aggressive operative management should this anatomical variation present in the presence of acute appendicitis.
Case presentation
We report the case of a 15-year-old African American girl who presented to our hospital with right lower quadrant pain and was subsequently found to have appendiceal duplication.
There are two categorical systems that have described and stratified appendiceal duplication. Both classification systems have been outlined and referenced in this case report. A computed tomography scan has been included to provide a visual aid to help identify true vermiform appendiceal duplication. The presence of this anatomical abnormality is not a reason for surgical intervention; however, should this be found in the setting of acute appendicitis, aggressive resection of both appendices is mandatory.
PMCID: PMC3310715  PMID: 22397591
4.  Fitness Cost of Resistance to Bt Cotton Linked with Increased Gossypol Content in Pink Bollworm Larvae 
PLoS ONE  2011;6(6):e21863.
Fitness costs of resistance to Bacillus thuringiensis (Bt) crops occur in the absence of Bt toxins, when individuals with resistance alleles are less fit than individuals without resistance alleles. As costs of Bt resistance are common, refuges of non-Bt host plants can delay resistance not only by providing susceptible individuals to mate with resistant individuals, but also by selecting against resistance. Because costs typically vary across host plants, refuges with host plants that magnify costs or make them less recessive could enhance resistance management. Limited understanding of the physiological mechanisms causing fitness costs, however, hampers attempts to increase costs. In several major cotton pests including pink bollworm (Pectinophora gossypiella), resistance to Cry1Ac cotton is associated with mutations altering cadherin proteins that bind this toxin in susceptible larvae. Here we report that the concentration of gossypol, a cotton defensive chemical, was higher in pink bollworm larvae with cadherin resistance alleles than in larvae lacking such alleles. Adding gossypol to the larval diet decreased larval weight and survival, and increased the fitness cost affecting larval growth, but not survival. Across cadherin genotypes, the cost affecting larval growth increased as the gossypol concentration of larvae increased. These results suggest that increased accumulation of plant defensive chemicals may contribute to fitness costs associated with resistance to Bt toxins.
PMCID: PMC3128109  PMID: 21738799
5.  Do We Practice What We Preach? A Review of Actual Clinical Practice with Regards to Preconception Care Guidelines 
Maternal and Child Health Journal  2006;10(Suppl 1):53-58.
Objectives: To review what past studies have found with regard to existing clinical practices and approaches to providing preconception care. Methods: A literature review between 1966 and September 2005 was performed using Medline. Key words included preconception care, preconception counseling, preconception surveys, practice patterns, pregnancy outcomes, prepregnancy planning, and prepregnancy surveys. Results: There are no current national recommendations that fully address preconception care; as a result, there is wide variability in what is provided clinically under the rubric of preconception care. Conclusions: In 2005, the Centers for Disease Control and Prevention sponsored a national summit regarding preconception care and efforts are underway to develop a uniform set of national recommendations and guidelines for preconception care. Understanding how preconception care is presently incorporated and manifested in current medical practices should help in the development of these national guidelines. Knowing where, how, and why some specific preconception recommendations have been successfully adopted and translated into clinical practice, as well as barriers to implementation of other recommendations or guidelines, is vitally important in developing an overarching set of national guidelines. Ultimately, the success of these recommendations rests on their ability to influence and shape women's health policy.
PMCID: PMC1592243  PMID: 16897374
Preconception care; Preconception counseling; Preconception surveys; Practice patterns; Pregnancy outcomes; Prepregnancy planning; Prepregnancy surveys
6.  Health Care Provider Knowledge and Practices Regarding Folic Acid, United States, 2002–2003 
Maternal and Child Health Journal  2006;10(Suppl 1):67-72.
Objective: To assess health care providers (HCP) knowledge and practices regarding folic acid (FA) use for neural tube defect (NTD) prevention. Methods: Two identical surveys were conducted among 611 obstetricians/gynecologists (OB/GYNs) and family/general physicians (FAM/GENs) (2002), and 500 physician assistants (PAs), nurse practitioners (NPs), certified nurse midwives (CNMs), and registered nurses (2003) to ascertain knowledge and practices regarding FA. For analysis, T-tests, univariate and multivariate logistic regression modeling were used. Results: Universally, providers knew that FA prevents birth defects. Over 88% knew when a woman should start taking folic acid for the prevention of NTDs; and over 85% knew FA supplementation beyond what is available in the diet is necessary. However, only half knew that 50% of all pregnancies in the United States are unplanned. Women heard information about multivitamins or FA most often during well woman visits in obstetrical/gynecology (ob/gyn) practice settings (65%), and about 50% of the time during well woman visits in family/general (fam/gen) practice settings and 50% of the time at gynecology visits (both settings). Among all providers, 42% did not know the correct FA dosage (400 μg daily). HCPs taking multivitamins were more than twice as likely to recommend multivitamins to their patients (Odds Ratio [OR] 2.27 95%, Confidence Interval [CI] 1.75–2.94). HCPs with lower income clients (OR 1.49, CI 1.22–1.81) and HCPs with practices having more than 10% minorities (OR 1.46, CI 1.11–1.92) were more likely to recommend supplements. NPs in ob/gyn settings were most likely and FAM/GENs were least likely to recommend supplements (OR 3.06, CL 1.36–6.90 and OR 0.64, CL 0.45–0.90 respectively). Conclusions: Knowledge about birth defects and the necessity of supplemental FA was high. Increasing knowledge about unintended pregnancy rates and correct dosages of FA is needed. The strongest predictor for recommending the use of FA supplements was whether the provider took a multivitamin.
PMCID: PMC1592153  PMID: 16721664
Health care provider; Folic acid; Knowledge; Behavior

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