The evolution of sour taste.

The evolutionary history of sour taste has been little studied. Through a combination of literature review and trait mapping on the vertebrate phylogenetic tree, we consider the origin of sour taste, potential cases of the loss of sour taste, and those factors that might have favoured changes in the valence of sour taste-from aversive to appealing. We reconstruct sour taste as having evolved in ancient fish. By contrast to other tastes, sour taste does not appear to have been lost in any major vertebrate taxa. For most species, sour taste is aversive. Animals, including humans, that enjoy the sour taste triggered by acidic foods are exceptional. We conclude by considering why sour taste evolved, why it might have persisted as vertebrates made the transition to land and what factors might have favoured the preference for sour-tasting, acidic foods, particularly in hominins, such as humans.

Sugar-seeking insects as a source of diverse bread-making yeasts with enhanced attributes.

Insects represent a particularly interesting habitat in which to search for novel yeasts of value to industry. Insect-associated yeasts have the potential to have traits relevant to modern food and beverage production due to insect-yeast interactions, with such traits including diverse carbohydrate metabolisms, high sugar tolerance, and general stress tolerance. Here, we consider the potential value of insect-associated yeasts in the specific context of baking. We isolated 63 yeast strains from 13 species of hymenoptera from the United States, representing 37 yeast species from 14 genera. Screening for the ability to ferment maltose, a sugar important for bread production, resulted in the identification of 13 strains of Candida, Lachancea, and Pichia species. We assessed their ability to leaven dough. All strains produced baked loaves comparable to a commercial baking strain of Saccharomyces cerevisiae. The same 13 strains were also grown under various sugar and salt conditions relevant to osmotic challenges experienced in the manufacturing processes and the production of sweet dough. We show that many of these yeast strains, most notably strains of Lachancea species, grow at a similar or higher rate and population size as commercial baker's yeast. We additionally assessed the comparative phenotypes and genetics of insect-associated S. cerevisiae strains unable to ferment maltose and identified baking-relevant traits, including variations in the HOG1 signaling pathway and diverse carbohydrate metabolisms. Our results suggest that non-conventional yeasts have high potential for baking and, more generally, showcase the success of bioprospecting in insects for identifying yeasts relevant for industrial uses.

Structure and Functional Attributes of Bacterial Communities in Premise Plumbing Across the United States.

Microbes that thrive in premise plumbing can have potentially important effects on human health. Yet, how and why plumbing-associated microbial communities vary across broad spatial scales remain undetermined. We characterized the bacterial communities in 496 showerheads collected from across the continental United States. The overall community structure, determined by 16S rRNA gene amplicon sequencing, revealed high levels of bacterial diversity. Although a large fraction of the observed variation in community composition could not be explained, differences in bacterial community composition were associated with water supply (private well water vs public municipal water), water source (groundwater vs surface water), and associated differences in water chemistry (pH and chlorine). Most notably, showerheads in homes supplied with public water had higher abundances of Blastomonas, Mycobacterium, and Porphyrobacter, while Pseudorhodoplanes, Novosphingobium, and Nitrospira were more abundant in those receiving private well water. We conducted shotgun metagenomic analyses on 92 of these samples to assess differences in genomic attributes. Public water-sourced showerheads had communities enriched in genes related to lipid and xenobiotic metabolisms, virulence factors, and antibiotic resistance. In contrast, genes associated with oxidative stress and membrane transporters were over-represented in communities from private well water-sourced showerheads compared to those supplied by public water systems. These results highlight the broad diversity of bacteria found in premise plumbing across the United States and the role of the water source and treatment in shaping the microbial community structure and functional potential.

Screen time use impacts low-income preschool children's sleep quality, tiredness, and ability to fall asleep.

BACKGROUND: Sleep is increasingly recognized as a vital part of health. Screen time has been linked to sleep quality in children. The purpose of this study was to analyze associations between screen time and sleep characteristics among low-income preschoolers. METHODS: A total of 1,700 preschool-aged children participated in this study at 50 federally and state-funded preschool centers in Michigan. Baseline measurement for an ongoing longitudinal intervention trial was obtained for cross-sectional use. At baseline, parents reported the number of hours their child spent engaging in screen time on a typical week day and weekend. An aggregate measure of total screen time was created. Parents reported on the quality of their child's sleep, how often they were tired during the day, and whether they had difficulty falling asleep. A mixed model linear regression was created to analyze data. RESULTS: Controlling for child's age, race, and parental income, children who engaged in more screen time were significantly more likely to have more trouble falling or staying asleep, be tired during the day, and had worse quality of sleep (P values = .004, .006 and .001, respectively). Spearman correlations of screen time, sleep variables and demographics show parents of Black children reported significantly higher weekly screen time than parents of non-Black children (r = 0.23, P < .001) and that tiredness was associated with Black race (r = 0.15, P < .001), Hispanic/Latino ethnicity (r = -0.14, P < .001), and parental education (r = 0.06, P = .016). CONCLUSION: This report confirms prior associations between screen time and sleep reported in other pediatric populations. Further research is needed to confirm these results in other populations using more rigorous measures of screen time, sleep, and physical activity, as well as longitudinal assessments. Despite these limitations, findings suggest that interventions to help parents limit children's screen time and impact their sleep health merit investigation.

Youth Perspectives of Prescription Pain Medication in the Opioid Crisis.

OBJECTIVE: To characterize current youth perspectives of prescription pain medication. STUDY DESIGN: In total, 1047 youths aged 14-24 years were recruited by targeted social media advertisements to match national demographic benchmarks. Youths were queried by open-ended text message prompts about exposure and access to prescription pain medication, perceived safety of prescribed and nonprescribed medication, and associations with the word "opioid." Responses were analyzed inductively for emerging themes and frequencies. RESULTS: Among 745 respondents (71.2% response rate), 439 identified as female (59.3%), 561 as white (75.8%), and mean age was 18.3 ± 3.2 years. Previous exposure to prescription pain medication was reported by 377 respondents (52.0%), most commonly related to dentistry (32.8%), surgery (19.2%), and injury (12.0%). Nonmedical sources of access to prescription pain medication were identified by 256 respondents (36.9%) and medical sources other than their doctor by an additional 111 respondents (16.0%). Three additional themes emerged from youth responses: (1) prescribed medication was thought to be safer than nonprescribed medication, based on trust in doctors; (2) risks of addiction and overdose were thought to be greater for nonprescribed medication; (3) respondents had a widely ranging understanding of the word "opioid," from historical to current events, medical to illicit substances, and personal to public associations. CONCLUSIONS: Although youths are aware of the opioid crisis, they perceive less risk of prescription pain medication prescribed by a doctor, than from other sources. Policies should target education to youth in clinical and nonclinical settings, highlighting the risks of addiction and overdose with all opioids.

Youth Preferences for Weight-Related Conversations.

Little guidance is available to clinicians on how to talk about weight with their patients. The aim of this study is to explore youth preferences for weight-related conversations. Participants came from the National MyVoice Text Message Cohort. Between 7/2017 and 01/2018, 952 MyVoice participants provided open-ended responses via text message to three questions about weight-related conversations ("Has your doctor ever talked to you about weight?", "What did he or she say?", and "What should a doctor NOT say when talking about weight?"). The presence of themes was coded using standard qualitative methods. Of the 952 respondents, 568 (60%) reported that their doctor had talked with them about weight. Of these, 85% indicated that their doctor had notified them of their weight, BMI, or weight status and/or the need to change their body weight and 16% had doctors who provided advice about weight control. Eight themes emerged from the analysis of responses to the question "What should a doctor NOT say when talking about weight?". The two most common themes were: (1): Avoid stigmatizing terms/language (32%); and (2) Do not shame patient for their weight (25%). Findings suggest that weight-related conversations do not reflect the preferences of the youth they are designed to benefit. Youth recommended that clinicians focus on health and sustainable behavioral solutions, avoid stigmatizing language and comparing them to others, and be aware of the potential harm associated with making assumptions that conflate weight with health behaviors, morality, or appearance.

Confidentiality in the Doctor-Patient Relationship: Perspectives of Youth Ages 14-24 Years.

OBJECTIVE: To describe the experiences of youth regarding confidentiality with their healthcare provider and how confidentiality affects their interactions with the healthcare system. STUDY DESIGN: Using MyVoice, a national mixed methods text message poll, 4 qualitative probes were asked to 1268 youth age 14-24 years from July 2017 through December 2017. Respondents were asked about their opinions and experiences with confidentiality in their healthcare. Data were analyzed using a modified grounded theory approach. RESULTS: The overall response rate was 75% (n = 948) with a mean age of 18.6 years (SD = 3.2). Respondents were mostly female (56%) and white (70%) with 44% reporting some college education or greater. Qualitative analysis revealed that the majority of youth have not had a conversation with their provider about confidentiality; many youth think all care should be confidential; youth worry about privacy and future discrimination; and youth may lie about their risk behaviors or not seek healthcare when concerned about confidentiality. CONCLUSIONS: Confidentiality in healthcare is concerning to many youth and affects how they interact with the healthcare system. It is imperative for healthcare providers to discuss confidentiality while building trusting relationships with each youth to provide the highest level of care for this vulnerable population.

"Baby Wants Tacos": Analysis of Health-Related Facebook Posts from Young Pregnant Women.

Objectives Pregnant young women gain more weight than recommended by the National Academy of Medicine, increasing the likelihood of adverse maternal and fetal outcomes. The purpose of this study is to use online social media to understand beliefs and practices surrounding weight gain, diet and exercise during pregnancy among young women. Methods Facebook posts were mined from young women ages 16 to 24 during pregnancy who were consented from two Midwest primary care clinics serving low-income communities. Natural language processing was used to identify posts related to weight gain, exercise and diet by keyword searching. Two investigators iteratively coded the mined posts and identified major themes around health behaviors. Outcome measures included the frequency of posts and major themes regarding health behaviors during pregnancy. Results Participants (n = 43) had a mean age of 21 (SD 2.3), and the largest subgroups identified as black (49%; 26% white, 16% Hispanic, 9% other) and having graduated from high school (49%; 24% completed some high school and 24% completed at least some post-secondary education). Among the 2899 pregnancy posts analyzed, 311 were related to weight. Major themes included eating behaviors and cravings (58% of identified posts), body image (24%), the influence of family, partners and friends (14%), and the desire to exercise (4%). Conclusions for practice Facebook posts revealed that young women often frame their thoughts and feelings regarding weight gain in pregnancy in the context of food cravings and body image and that friends and family are important influencers to these behaviors.

Advice given by community members to pregnant women: a mixed methods study.

BACKGROUND: Smoking and excess weight gain during pregnancy have been shown to have serious health consequences for both mothers and their infants. Advice from friends and family on these topics influences pregnant women's behaviors. The purpose of our study was to compare the advice that community members give pregnant women about smoking versus the advice they give about pregnancy weight gain. METHODS: A survey was sent via text messaging to adults in a diverse, low-income primary care clinic in 2015. Respondents were asked what advice (if any) they have given pregnant women about smoking or gestational weight gain and their comfort-level discussing the topics. Descriptive statistics were used to characterize the sample population and to determine response rates. Open-ended responses were analyzed qualitatively using grounded theory analysis with an overall convergent parallel mixed methods design. RESULTS: Respondents (n = 370) were 77 % female, 40 % black, and 25 % reported education of high school or less. More respondents had spoken to pregnant women about smoking (40 %, n = 147) than weight gain (20 %, n = 73). Among individuals who had not discussed either topic (n = 181), more reported discomfort in talking about weight gain (65 %) compared to smoking (34 %; p < 0.0001). Advice about smoking during pregnancy (n = 148) was frequently negative, recommending abstinence and identifying smoking as harmful for baby and/or mother. Advice about weight gain in pregnancy (n = 74) revealed a breadth of messages, from reassurance about all weight gain ("Eat away" or "It's ok if you are gaining weight"), to specific warnings against excess weight gain ("Too much was dangerous for her and the baby."). CONCLUSIONS: Many community members give advice to pregnant women. Their advice reveals varied perspectives on the effects of pregnancy weight gain. Compared to a nearly ubiquitous understanding of the harms of smoking during pregnancy, community members demonstrated less awareness of and willingness to discuss the harms of excessive weight gain. Beyond educating pregnant women, community-level interventions may also be important to ensure that the information pregnant women receive supports healthy behaviors and promotes the long-term health of both moms and babies.

Climate, climate change and the global diversity of human houses.

Globally, human house types are diverse, varying in shape, size, roof type, building materials, arrangement, decoration and many other features. Here we offer the first rigorous, global evaluation of the factors that influence the construction of traditional (vernacular) houses. We apply macroecological approaches to analyse data describing house features from 1900 to 1950 across 1000 societies. Geographic, social and linguistic descriptors for each society were used to test the extent to which key architectural features may be explained by the biophysical environment, social traits, house features of neighbouring societies or cultural history. We find strong evidence that some aspects of the climate shape house architecture, including floor height, wall material and roof shape. Other features, particularly ground plan, appear to also be influenced by social attributes of societies, such as whether a society is nomadic, polygynous or politically complex. Additional variation in all house features was predicted both by the practices of neighouring societies and by a society's language family. Collectively, the findings from our analyses suggest those conditions under which traditional houses offer solutions to architects seeking to reimagine houses in light of warmer, wetter or more variable climates.

An examination of sexual orientation group patterns in mammographic and colorectal screening in a cohort of U.S. women.

PURPOSE: Underutilization of cancer screening has been found especially to affect socially marginalized groups. We investigated sexual orientation group patterns in breast and colorectal cancer screening adherence. METHODS: Data on breast and colorectal cancer screening, sexual orientation, and sociodemographics were gathered prospectively from 1989 through 2005 from 85,759 U.S. women in the Nurses' Health Study II. Publicly available data on state-level healthcare quality and sexual-orientation-related legal protections were also gathered. Multivariable models were used to estimate sexual orientation group differences in breast and colorectal cancer screening, controlling for sociodemographics and state-level healthcare quality and legal protections for sexual minorities. RESULTS: Receipt of a mammogram in the past 2 years was common though not universal and differed only slightly by sexual orientation: heterosexual 84 %, bisexual 79 %, and lesbian 82 %. Fewer than half of eligible women had ever received a colonoscopy or sigmoidoscopy, and rates did not differ by sexual orientation: heterosexual 39 %, bisexual 39 %, and lesbian 42 %. In fully adjusted models, state-level healthcare quality score, though not state-level legal protections for sexual minorities, was positively associated with likelihood of being screened for all women regardless of sexual orientation. CONCLUSIONS: Concerns have been raised that unequal healthcare access for sexual orientation minorities may adversely affect cancer screening. We found small disparities in mammography and none in colorectal screening, though adherence to colorectal screening recommendations was uniformly very low. Interventions are needed to increase screening in women of all sexual orientation groups, particularly in areas with poor healthcare policies.

Sourdough starters exhibit similar succession patterns but develop flour-specific climax communities.

The microbial fermentation behind sourdough bread is among our oldest technologies, yet there are many opportunities for sourdough science to learn from traditional bakers. We analyzed 16S rRNA sequences in R to assess the bacterial community structure and performance of 40 starters grown from 10 types of flour over 14 days, and identified six distinct stages of succession. At each stage, bacterial taxa correlate with determinants of bread quality including pH, rise, and aromatic profile. Day 1 starter cultures were dominated by microorganisms commonly associated with plants and flour, and by aromas similar to toasted grain/cereal. Bacterial diversity peaked from days 2-6 as taxa shifted from opportunistic/generalist bacteria associated with flour inputs, toward specialized climax bacterial communities (days 10-14) characterized by acid-tolerant taxa and fruity (p < 3.03e-03), sour (p < 1.60e-01), and fermented (p < 1.47e-05) aromas. This collection of traits changes predictably through time, regardless of flour type, highlighting patterns of bacterial constraints and dynamics that are conserved across systems and scales. Yet, while sourdough climax communities exhibit similar markers of maturity (i.e., pH ≤ 4 and enriched in Lactobacillus (mean abundance 48.1%), Pediococcus (mean abundance 22.7%), and/or Gluconobacter (mean abundance 19.1%)), we also detected specific taxa and aromas associated with each type of flour. Our results address important ecological questions about the relationship between community structure and starter performance, and may enable bakers to deliberately select for specific sourdough starter and bread characteristics.

A Novel Milli-fluidic Liver Tissue Chip with Continuous Recirculation for Predictive Pharmacokinetics Applications.

A crucial step in lead selection during drug development is accurate estimation and optimization of hepatic clearance using in vitro methods. However, current methods are limited by factors such as lack of physiological relevance, short culture/incubation times that are not consistent with drug exposure patterns in patients, use of drug absorbing materials, and evaporation during long-term incubation. To address these technological needs, we developed a novel milli-fluidic human liver tissue chip (LTC) that was designed with continuous media recirculation and optimized for hepatic cultures using human primary hepatocytes. Here, we characterized the LTC using a series of physiologically relevant metrics and test compounds to demonstrate that we could accurately predict the PK of both low- and high-clearance compounds. The non-biological characterization indicated that the cyclic olefin copolymer (COC)-based LTC exhibited negligible evaporation and minimal non-specific binding of drugs of varying ionic states and lipophilicity. Biologically, the LTC exhibited functional and polarized hepatic culture with sustained metabolic CYP activity for at least 15 days. This long-term culture was then used for drug clearance studies for low- and high-clearance compounds for at least 12 days, and clearance was estimated for a range of compounds with high in vitro-in vivo correlation (IVIVC). We also demonstrated that LTC can be induced by rifampicin, and the culture age had insignificant effect on depletion kinetic and predicted clearance value. Thus, we used advances in bioengineering to develop a novel purpose-built platform with high reproducibility and minimal variability to address unmet needs for PK applications.

Researching COVID to Enhance Recovery (RECOVER) adult study protocol: Rationale, objectives, and design.

IMPORTANCE: SARS-CoV-2 infection can result in ongoing, relapsing, or new symptoms or other health effects after the acute phase of infection; termed post-acute sequelae of SARS-CoV-2 infection (PASC), or long COVID. The characteristics, prevalence, trajectory and mechanisms of PASC are ill-defined. The objectives of the Researching COVID to Enhance Recovery (RECOVER) Multi-site Observational Study of PASC in Adults (RECOVER-Adult) are to: (1) characterize PASC prevalence; (2) characterize the symptoms, organ dysfunction, natural history, and distinct phenotypes of PASC; (3) identify demographic, social and clinical risk factors for PASC onset and recovery; and (4) define the biological mechanisms underlying PASC pathogenesis. METHODS: RECOVER-Adult is a combined prospective/retrospective cohort currently planned to enroll 14,880 adults aged ≥18 years. Eligible participants either must meet WHO criteria for suspected, probable, or confirmed infection; or must have evidence of no prior infection. Recruitment occurs at 86 sites in 33 U.S. states, Washington, DC and Puerto Rico, via facility- and community-based outreach. Participants complete quarterly questionnaires about symptoms, social determinants, vaccination status, and interim SARS-CoV-2 infections. In addition, participants contribute biospecimens and undergo physical and laboratory examinations at approximately 0, 90 and 180 days from infection or negative test date, and yearly thereafter. Some participants undergo additional testing based on specific criteria or random sampling. Patient representatives provide input on all study processes. The primary study outcome is onset of PASC, measured by signs and symptoms. A paradigm for identifying PASC cases will be defined and updated using supervised and unsupervised learning approaches with cross-validation. Logistic regression and proportional hazards regression will be conducted to investigate associations between risk factors, onset, and resolution of PASC symptoms. DISCUSSION: RECOVER-Adult is the first national, prospective, longitudinal cohort of PASC among US adults. Results of this study are intended to inform public health, spur clinical trials, and expand treatment options. REGISTRATION: NCT05172024.

A physiological trait-based approach to predicting the responses of species to experimental climate warming.

Physiological tolerance of environmental conditions can influence species-level responses to climate change. Here, we used species-specific thermal tolerances to predict the community responses of ant species to experimental forest-floor warming at the northern and southern boundaries of temperate hardwood forests in eastern North America. We then compared the predictive ability of thermal tolerance vs. correlative species distribution models (SDMs) which are popular forecasting tools for modeling the effects of climate change. Thermal tolerances predicted the responses of 19 ant species to experimental climate warming at the southern site, where environmental conditions are relatively close to the ants' upper thermal limits. In contrast, thermal tolerances did not predict the responses of the six species in the northern site, where environmental conditions are relatively far from the ants' upper thermal limits. Correlative SDMs were not predictive at either site. Our results suggest that, in environments close to a species' physiological limits, physiological trait-based measurements can successfully forecast the responses of species to future conditions. Although correlative SDMs may predict large-scale responses, such models may not be accurate for predicting site-level responses.

Computational modeling of corneal and scleral collagen photocrosslinking.

Scleral photocrosslinking is increasingly investigated for treatment of myopia and glaucoma. In this study a computational model was developed to predict crosslinking efficiency of visible/near infrared photosensitizers in the sclera. Photocrosslinking was validated against riboflavin corneal crosslinking experimental studies and subsequently modeled for the sensitizer, methylene blue, administered by retrobulbar injection to the posterior sclera and irradiated with a transpupillary light beam. Optimal ranges were determined for treatment parameters including light intensity, methylene blue concentration, injection volume, and inspired oxygen concentration. Additionally, sensitivity of crosslinking to various parameters was quantified. The most sensitive parameters were oxygen concentration in the injection solution, scleral thickness, and injection reservoir thickness (i.e., injection volume).

Cost-effectiveness of a motivational interviewing obesity intervention versus usual care in pediatric primary care offices.

OBJECTIVE: This study aimed to assess the incremental cost-effectiveness ratio (ICER) of a 2-year motivational interviewing (MI) intervention versus usual primary care. METHODS: A national trial was implemented in the Pediatric Research in Office Settings (PROS) network of the American Academy of Pediatrics to evaluate MI versus usual care for children (2-8 years old; baseline BMI 85th-97th percentiles). Health care use, food costs, provider fees, and training costs were assessed, and sensitivity analyses were conducted. Primary outcome was the ICER, calculated as cost per unit change in BMI percentile for intervention versus usual care. RESULTS: At 2 years, 72% of enrolled parent/child dyads were retained; 312 children were included in the analysis. Mean BMI percentile point change was -4.9 and -1.8 for the intervention and control, respectively, yielding an incremental reduction of 3.1 BMI percentile points (95% CI: 1.2-5.0). The intervention cost $1051 per dyad ($658 for training DVD development). Incorporating health care and non-health care costs, the intervention ICER was $363 (range from sensitivity analyses: cost saving, $3159) per BMI percentile point decrease per participant over 2 years. CONCLUSIONS: Training pediatricians, nurse practitioners, and registered dietitians to deliver MI-based interventions for childhood obesity in primary care is clinically effective and acceptably cost-effective. Future work should explore this approach in broader dissemination.

Evaluation of Spatially Targeted Scleral Stiffening on Neuroprotection in a Rat Model of Glaucoma.

Purpose: Scleral stiffening may protect against glaucomatous retinal ganglion cell (RGC) loss or dysfunction associated with ocular hypertension. Here, we assess the potential neuroprotective effects of two treatments designed to stiffen either the entire posterior sclera or only the sclera adjacent to the peripapillary sclera in an experimental model of glaucoma. Methods: Rat sclerae were stiffened in vivo using either genipin (crosslinking the entire posterior sclera) or a regionally selective photosensitizer, methylene blue (stiffening only the juxtaperipapillary region surrounding the optic nerve). Ocular hypertension was induced using magnetic microbeads delivered to the anterior chamber. Morphological and functional outcomes, including optic nerve axon count and appearance, retinal thickness measured by optical coherence tomography, optomotor response, and electroretinography traces, were assessed. Results: Both local (juxtaperipapillary) and global (whole posterior) scleral stiffening treatments were successful at increasing scleral stiffness, but neither provided demonstrable neuroprotection in hypertensive eyes as assessed by RGC axon counts and appearance, optomotor response, or electroretinography. There was a weak indication that scleral crosslinking protected against retinal thinning as assessed by optical coherence tomography. Conclusions: Scleral stiffening was not demonstrated to be neuroprotective in ocular hypertensive rats. We hypothesize that the absence of benefit may in part be due to RGC loss associated with the scleral stiffening agents themselves (mild in the case of genipin, and moderate in the case of methylene blue), negating any potential benefit of scleral stiffening. Translational Relevance: The development of scleral stiffening as a neuroprotective treatment will require the identification of better tolerated stiffening protocols and further preclinical testing.

High burden of homelessness among sexual-minority adolescents: findings from a representative Massachusetts high school sample.

OBJECTIVES: We compared the prevalence of current homelessness among adolescents reporting a minority sexual orientation (lesbian/gay, bisexual, unsure, or heterosexual with same-sex sexual partners) with that among exclusively heterosexual adolescents. METHODS: We combined data from the 2005 and 2007 Massachusetts Youth Risk Behavior Survey, a representative sample of public school students in grades 9 though 12 (n = 6317). RESULTS: Approximately 25% of lesbian/gay, 15% of bisexual, and 3% of exclusively heterosexual Massachusetts public high school students were homeless. Sexual-minority males and females had an odds of reporting current homelessness that was between 4 and 13 times that of their exclusively heterosexual peers. Sexual-minority youths' greater likelihood of being homeless was driven by their increased risk of living separately from their parents or guardians. CONCLUSIONS: Youth homelessness is linked with numerous threats such as violence, substance use, and mental health problems. Although discrimination and victimization related to minority sexual orientation status are believed to be important causal factors, research is needed to improve our understanding of the risks and protective factors for homelessness and to determine effective strategies to prevent homelessness in this population.

The toughest animals of the Earth versus global warming: Effects of long-term experimental warming on tardigrade community structure of a temperate deciduous forest.

Understanding how different taxa respond to global warming is essential for predicting future changes and elaborating strategies to buffer them. Tardigrades are well known for their ability to survive environmental stressors, such as drying and freezing, by undergoing cryptobiosis and rapidly recovering their metabolic function after stressors cease. Determining the extent to which animals that undergo cryptobiosis are affected by environmental warming will help to understand the real magnitude climate change will have on these organisms. Here, we report on the responses of tardigrades within a five-year-long, field-based artificial warming experiment, which consisted of 12 open-top chambers heated to simulate the projected effects of global warming (ranging from 0 to 5.5°C above ambient temperature) in a temperate deciduous forest of North Carolina (USA). To elucidate the effects of warming on the tardigrade community inhabiting the soil litter, three community diversity indices (abundance, species richness, and Shannon diversity) and the abundance of the three most abundant species (Diphascon pingue, Adropion scoticum, and Mesobiotus sp.) were determined. Their relationships with air temperature, soil moisture, and the interaction between air temperature and soil moisture were tested using Bayesian generalized linear mixed models. Despite observed negative effects of warming on other ground invertebrates in previous studies at this site, long-term warming did not affect the abundance, richness, or diversity of tardigrades in this experiment. These results are in line with previous experimental studies, indicating that tardigrades may not be directly affected by ongoing global warming, possibly due to their thermotolerance and cryptobiotic abilities to avoid negative effects of stressful temperatures, and the buffering effect on temperature of the soil litter substrate.