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Insects behaviorally thermoregulate across the diel cycle, and their preferred microhabitats change based on current resources available and the thermal performance optima of traits. Specific combinations of traits being prioritized are set by life history strategies, making life history an important intrinsic determinant of thermal preferences. However, we do not know how life history strategies shape plasticity of behavioral thermoregulation, limiting our ability to predict responses to environmental variability. We compared female variable field crickets (Gryllus lineaticeps) that are flight-capable (long-winged) and flightless (short-winged) to test the hypothesis that life history strategy determines plasticity of thermal preferences across the diel cycle and following starvation. Thermal preferences were elevated during the nocturnal activity period, and long-winged crickets preferred warmer temperatures compared to short-winged crickets across the diel cycle when fully fed. However, thermal preferences of starved crickets were reduced compared to fed crickets. The reduction in thermal preferences was greater in long-winged crickets, resulting in similar thermal preferences between starved long- and short-winged individuals and reflecting a more plastic response. Thus, life history does determine plasticity in thermoregulatory behaviors following resource limitations and effects of life history on thermal preferences are context dependent.

Temperature is known to influence many aspects of organisms and is frequently linked to geographical species distributions. Despite the importance of a broad understanding of an animal's thermal biology, few studies incorporate more than one metric of thermal biology. Here we examined an elevational assemblage of Habronattus jumping spiders to measure different aspects of their thermal biology including thermal limits (CTmin, CTmax), thermal preference, V̇CO2 as proxy for metabolic rate, locomotor behavior and warming tolerance. We used these data to test whether thermal biology helped explain how species were distributed across elevation. Habronattus had high CTmax values, which did not differ among species across the elevational gradient. The highest-elevation species had a lower CTmin than any other species. All species had a strong thermal preference around 37 °C. With respect to performance, one of the middle elevation species was significantly less temperature-sensitive in metabolic rate. Differences between species with respect to locomotion (jump distance) were likely driven by differences in mass, with no differences in thermal performance across elevation. We suggest that Habronattus distributions follow Brett's rule, a rule that predicts more geographical variation in cold tolerance than heat. Additionally, we suggest that physiological tolerances interact with biotic factors, particularly those related to courtship and mate choice to influence species distributions. Habronattus also had very high warming tolerance values (> 20 °C, on average). Taken together, these data suggest that Habronattus are resilient in the face of climate-change related shifts in temperature.

Purpose/Objectives: The purpose of this study was to assess the current practices used in school nutrition programs to prevent intentional acts of food contamination or tampering with food. Methods: A convenience sample of school districts (n=2023) was randomly selected, representing two states from each of the seven USDA regions. School food authorities from 320 districts in 14 states participated in a live structured interview guided by a questionnaire consisting of 31 questions concerning food defense practices. The researchers conducted the interviews with videoconferencing technology or telephone and entered responses directly into an online survey to collect the data. Descriptive statistics included frequencies, percentages, and means. Results: Results suggest that many school nutrition programs have room to improve food defense programs, practices, and understanding about food defense in their districts. Almost 68% of districts and 66% of school nutrition programs reported not having a food defense plan. While the opportunity for improvement was evident in several areas, some practices to prevent an intentional food defense incident were also reported. Training was reported as lacking by 44% of the sample. Application to Child Nutrition Professionals: Results from this study can be used to bring awareness about food defense practices in the school environment, especially where practices may not be evident through existing food safety plans. It is important that school nutrition programs follow recommended standards to reduce risks and develop best practices for overall safety. Stakeholders involved in school nutrition programs can support the prevention of intentional food contamination by advocating for district and staff training and by calling attention to practices that might represent a high risk for the school nutrition program.

ObjectivesTo evaluate safety outcomes from clinical studies of a 12-month contraceptive vaginal system (CVS) releasing an average of segesterone acetate (SA) 150 mcg and ethinyl estradiol (EE) 13 mcg daily.Study designWe integrated clinical safety data from nine studies in which women used the CVS for 21 consecutive days and removed it for 7 days of each 28-day cycle. Four studies used the final manufactured CVS, including a 1-year pharmacokinetic study, two 1-year phase 3 trials and a second-year treatment extension study. We assessed safety by evaluating adverse events women reported in a daily diary. We also included data from focused safety studies evaluating endometrial biopsies, vaginal microbiology and liver proteins from one of the phase 3 studies.ResultsThe combined studies included 3052 women; 2308 women [mean age 26.7±5.1 years; mean body mass index (BMI) 24.1±3.7 kg/m2] received the final manufactured CVS, of whom 999 (43.3%) completed 13 cycles of use. Women using the final CVS most commonly reported adverse events of headache (n=601, 26%), nausea (n=420, 18%), vaginal discharge/vulvovaginal mycotic infection (n=242, 10%) and abdominal pain (n=225, 10%). Few (29 kg/m2 (n=2)]. During 21,482 treatment cycles in the phase 3 studies evaluable for expulsion, women reported partial expulsions in 4259 (19.5%) cycles and complete expulsions in 1509 (7%) cycles, most frequently in the initial cycle [499/2050 (24.3%) and 190/2050 (9.3%), respectively]. Safety-focused studies revealed no safety concerns.ConclusionThe 1-year SA/EE CVS has an acceptable safety profile. Additional studies are warranted in obese women at higher risk of VTE.ImplicationsThis 1-year contraceptive vaginal system represents a new long-term, user-controlled and procedure-free option with a safety profile similar to other combination hormonal contraceptives. The same precautions currently used for combination hormonal contraceptive prescriptions apply to this new contraceptive vaginal system.

The influence of the solution environment on the solution crystallisation of the conformational polymorphic forms I and II of tolfenamic acid is assessed through integration of multi-scale (molecular, cluster and crystallographic) modelling with polymorphic screening using polythermal crystallisation as a function of solvent selection. Solid-state analysis reveals the contrasting crystal chemistry with the strongest synthon involving hydrogen bonding synthons and π–π van der Waals interactions for forms I and II, respectively. Analysis of the molecular conformational energies reveals molecular structures for forms I and II to be very close which is matched by their calculated lattice energies. Crystallisation as a function of both solute concentration and solution cooling rate reveals form II to be mostly more preferred than form I. The higher stability of the form II conformer together with its easier conformational adjustment during the formation of form II crystals, is consistent with its greater crystallisability compared to the more stable form I. Solute concentration analysis of the relative stabilities of the two forms as a function of their sizes reveals that smaller cluster sizes are required to stabilise the crystal structure for form I with respect to form II. Polymorphic screening as a function of solvent confirms the predicted poor crystallisability of form I whose crystallisation is preferred at higher initial solute concentrations and lower cooling rates in polar solvents but less so for the more apolar solvent toluene, the latter being consistent with π–π solute/solvent interactions promoting the formation of hydrogen bonded solute/solute synthons at the expense of π–π interactions. Modelling work correlates well with the observed crystallisation behaviour, highlighting the importance of understanding solvent selection and solution state structure at the molecular-scale level for directing polymorphic outcomes, as confirmed by the higher crystallisability of the metastable form II. [ABSTRACT FROM AUTHOR]