20 research outputs found
Sexual Dimorphism of Staminate- and Pistillate-Phase Flowers of Saponaria officinalis (Bouncing Bet) Affects Pollinator Behavior and Seed Set
The sequential separation of male and female function in flowers of dichogamous species allows for the evolution of differing morphologies that maximize fitness through seed siring and seed set. We examined staminate- and pistillate-phase flowers of protandrous Saponaria officinalis for dimorphism in floral traits and their effects on pollinator attraction and seed set. Pistillate-phase flowers have larger petals, greater mass, and are pinker in color, but due to a shape change, pistillate-phase flowers have smaller corolla diameters than staminate-phase flowers. There was no difference in nectar volume or sugar content one day after anthesis, and minimal evidence for UV nectar guide patterns in staminate- and pistillate-phase flowers. When presented with choice arrays, pollinators discriminated against pistillate-phase flowers based on their pink color. Finally, in an experimental garden, in 2012 there was a negative correlation between seed set of an open-pollinated, emasculated flower and pinkness (as measured by reflectance spectrometry) of a pistillate-phase flower on the same plant in plots covered with shade cloth. In 2013, clones of genotypes chosen from the 2012 plants that produced pinker flowers had lower seed set than those from genotypes with paler flowers. Lower seed set of pink genotypes was found in open-pollinated and hand-pollinated flowers, indicating the lower seed set might be due to other differences between pink and pale genotypes in addition to pollinator discrimination against pink flowers. In conclusion, staminate- and pistillate-phase flowers of S. officinalis are dimorphic in shape and color. Pollinators discriminate among flowers based on these differences, and individuals whose pistillate-phase flowers are most different in color from their staminate-phase flowers make fewer seeds. We suggest morphological studies of the two sex phases in dichogamous, hermaphroditic species can contribute to understanding the evolution of sexual dimorphism in plants without the confounding effects of genetic differences between separate male and female individuals
Research Note: Factors associated with skin cleaning prior to injection among drug users.
Injection drug users are at risk for a variety of infections when hygienic injection practices are not performed. Disinfecting the injection site prior to injecting reduces the risk of bacterial infections but has been overlooked in many prevention efforts. Using what is known about factors associated with risk-reduction behaviors of disinfecting equipment, we evaluated a model to determine whether those factors are associated with disinfection of the injection site. Sociodemographic and behavioral data were collected in interviews with 600 injection drug users. The majority of injection drug users do not clean the injection site prior to injecting. Results indicate that gender, ethnicity, and frequency of injection were significantly related to whether or not an injector cleaned the injection site. Failure to clean the injection site prior to injecting is a common practice and constitutes a health risk among injection drug users, particularly in a population prone to other infections. Prevention efforts need to incorporate all levels of sterilization procedures when working with these high risk populations. </jats:p
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Predictors of HIV Testing and Intention to Test Among Hispanic Farmworkers in South Florida
This study examined the predictors of HIV testing and factors associated with intention to accept a free HIV test among 244 Hispanic migrant/seasonal farmworkers in South Florida.Time and space sampling procedures were used to recruit participants in public venues. Bilingual staff interviewed eligible respondents in these settings.Despite high rates of sexual risk, only 21% of respondents had been tested for HIV. The majority of those tested were females tested during prenatal care. In multivariable logistic regression analyses, being female (odds ratio [OR] = 3.73), having at least 12 years of education (OR = 4.46), earning more than $201 per week (OR = 2.76), and ever having used marijuana (OR = 3.31) were positively associated with having been tested for HIV, while not being documented (OR = 0.24) and having rated one's health as "very good" or "good" (OR = 0.42) were negatively associated with testing. The multivariable predictors of intention to accept a free HIV test were having visited a health care provider and/or an emergency room in the past 12 months (OR = 1.97), having been tested for HIV (OR = 2.36), preferring an HIV test that used a finger stick for specimen collection with results given in 30 minutes (OR = 4.47), and worrying "some" or "a lot" about getting HIV (OR = 3.64). Women (OR = 0.52) were less likely than men to intend to accept a free HIV test.Our findings highlight the importance of routinely offering HIV testing to sexually active individuals in high HIV prevalence areas. They also suggest the need to make testing more accessible to migrant and seasonal farmworkers
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Cruising in Cyber Space: Comparing Internet Chat Room versus Community Venues for Recruiting Hispanic men Who Have Sex with Men to Participate in Prevention Studies
Difficulties with recruitment of hidden populations, such as Hispanic men who have sex with men (MSM), have hampered HIV prevention research, leading researchers to explore alternative recruitment modalities such as the Internet. In this paper, we compare the efficiency and cost of recruiting HMSM from Internet chat rooms versus community venues and examine the differences between participants recruited from each type of venue. Internet recruitment was more efficient and somewhat less costly than community recruitment. Although the two groups were comparable in most demographic factors and HIV risk behaviors, Internet recruits were more likely to be bisexual, more likely to be HIV seropositive, had a higher level of education, and reported higher levels of psychological distress and lower levels of gay community attachment. Implications of our findings for using Internet chatrooms as recruitment venues are discussed
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High Rates of Club Drug Use and Risky Sexual Practices Among Hispanic Men Who Have Sex with Men in Miami, Florida
This study measured use of club drugs among 262 Hispanic men who have sex with men (MSM) recruited at community venues in Miami-Dade County, Florida in 2001. More than 50% of men used club drugs, and 36% used them in the last 3 months. Lifetime and 3-month rates were: ecstasy (36% and 20%), cocaine (34% and 12%), amyl nitrates (28% and 9%), and crystal methamphetamine (20% and 15%). Thirty-six percent had used two or more drugs (polydrug use) in their lifetime and 20% reported polydrug use in the last 3 months. Club drug users had significantly more sex partners in the last 12 months than nonclub drug users. High rates (35%) of unprotected anal sex in the last 3 months were reported by both groups. Men who reported polydrug use in the last 3 months were significantly more likely than men who used a single club drug to have had sex under the influence of club drugs (83% vs. 57%; X2 = 7.4, p = 0.006). At the multivariate level, a significant association between preference for use of English and lifetime club drug use emerged. Effective interventions to reduce club drug use and risky sex for Hispanic MSM are needed
The Internet as recruitment tool for HIV studies: Viable strategy for reaching at-risk Hispanic MSM in Miami?
Although use of the Internet as a vehicle for HIV/STI research is increasing, its viability to recruit at-risk populations such as Hispanic men who have sex with men (HMSM) to participate in community-based HIV studies is in its infancy.We report on the first 171 participants enrolled in an ongoing study exploring use of the Internet to recruit Hispanic men who have sex with men (HMSM) living in Miami-Dade County, Florida to participate in community-based studies. We report our initial success with chat-room recruitment and describe the sexual and drug use practices of the initial set of participants who were recruited through the Internet. In addition, we describe the formative work conducted to develop the Internet recruitment procedures we are testing. In two months, we spent 211 hours recruiting in chat-rooms and engaged 735 chatters. One hundred and seventy-six men came to our community sites; 172 (98%) were eligible and completed an audio computer-assisted self-interview. In the previous six months, 94.7% of participants had anal sex; 48.9% did not use condoms for anal sex or used them inconsistently; and 48.5% had used club drugs. Six-month use rates for individual drugs were: poppers (31.6%), cocaine (15.8%), ecstasy (14%) and crystal methamphetamines (11.7%). Use of club drugs was significantly associated with unprotected insertive and unprotected receptive anal sex. These initial findings point to the Internet’s potential as a tool for recruiting at-risk Hispanic MSM for community studies
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Predictors of HIV risk among Hispanic farm workers in South Florida: women are at higher risk than men
This study examined factors associated with being at risk of sexually acquiring HIV among a community sample of 244 Hispanic migrant and seasonal farm workers. Bilingual staff interviewed respondents anonymously at worksites, camps, and other public venues in South Florida during the 2002 winter/spring growing season. The following variables were positively associated with being at risk of sexually acquiring HIV in multivariable analyses: being female; being married; having "some" or "a lot" of knowledge about HIV transmission, having ever used marijuana, having two or more sex partners in the last 12 months, and having had a sexually transmitted infection. The findings heighten the importance of recognizing women's elevated risk of HIV infection and conducting further studies to examine the factors associated with this increased risk. The study is an important first step toward developing tailored HIV prevention interventions for this at-risk, understudied population
Surfing New Territory: Club-Drug Use and Risky Sex Among Hispanic Men Who Have Sex with Men Recruited on the Internet
The Internet presents unique and growing opportunities for conducting HIV/ STD research. This article reports on the first 171 participants enrolled in an ongoing study examining use of the Internet to recruit Hispanic men who have sex with men (HMSM) living in an AIDS epicenter to participate in community-based studies. First, it describes initial success with chatroom recruitment. Second, it compares the demographic, psychosocial, and sexual risk practices among HMSM recruited through the Internet who had used club drugs in the last 6 months and those who had not. In 2 months, 211 hours were spent recruiting in chatrooms; 735 chatroom users were engaged. Researchers used a scripted dialogue to describe the study and to invite chatroom users to visit the study’s community sites for screening and enrollment. One hundred and seventy-six men came to the community sites; 172 (98%) were eligible and completed an audio-computer assisted self-interview. In the last 6 months, 48.5% of the sample had used club drugs [defined as cocaine, crystal methamphetamines (crystal), amyl nitrites (poppers), Ecstasy, gammahydroxybutyrate (GHB), ketamine (Special K), and Viagra]. The proportion of men reporting use of each drug was: cocaine (15.8%), crystal (11.7%), poppers (31.6%), Ecstasy (14%), GHB (3.5%), Special K (3.5%), and Viagra (19.3%). In multivariate analyses, having higher number of sex partners, having higher social isolation scores, and having engaged in unprotected receptive anal intercourse were significantly associated with club-drug use. These initial findings suggest that high-risk HMSM can be successfully recruited through chatroom dialogues to participate in community-based HIV studies. The alarmingly high rates of club-drug use and risky sexual practices among HMSM underscore the need for effective HIV preventive interventions for this population
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Response to Letter to the Editor: Alcohol Use Disorders and Bariatric Surgery
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Cetacean occurrence offshore of Washington from long-term passive acoustic monitoring
AbstractA variety of cetacean species inhabit the productive waters offshore of Washington State, USA. Although the general presence of many of these species has been documented in this region, our understanding of fine-scale habitat use is limited. Here, passive acoustic monitoring was used to investigate the spatial and temporal distributions of ten cetacean species at three locations offshore of Washington. Between 2004 and 2013, a total of 2845 days of recordings were collected from sites on the continental shelf and slope, and in a submarine canyon. Acoustic presence was higher for all species at sites farther offshore. Detections were highest during the fall and winter for blue (Balaenoptera musculus), fin (B. physalus), and humpback whales (Megaptera novaeangliae), likely related to reproductive behavior, while minke whales (B. acutorostrata) were only detected on two days. Odontocetes showed temporal separation, with sperm whale (Physeter macrocephalus) detections highest in spring, Risso’s (Grampus griseus) and Pacific white-sided dolphins (Lagenorhynchus obliquidens) highest in summer, and Stejneger’s beaked whales (Mesoplodon stejnegeri), Cuvier’s beaked whales (Ziphius cavirostris), and the BW37V signal type highest in winter or spring. There was interannual variation in detections for most mysticete species, which may be linked to oceanographic conditions: blue and fin whale detections increased during 2007 and 2008, and fin and humpback whale detections increased in 2011. These results inform our understanding of cetacean behavior and habitat use in this region and may aid in the development of conservation strategies suited to the dynamic conditions that drive cetacean distribution