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The non-target effects of pesticides are an area of growing concern, particularly for ecologically and economically important organisms such as bees. Much of the previous research on the effects of neonicotinoids, a class of insecticide that has gained attention for non-target effects, on bees focused on the consumption of contaminated food resources by a limited number of eusocial species. However, neonicotinoids are known to accumulate and persist in soils at concentrations 2 to 60 times greater than in food resources, and may represent an important route of exposure for diverse and ecologically important ground-nesting bees. This study aimed to assess the effect of chronic contact exposure to realistic soil concentrations of imidacloprid, the most widely used neonicotinoid pesticide, on bee longevity, development speed, and body mass. Cohorts of Osmia lignaria and Megachile rotundata were used as proxies for ground-nesting species. We observed species- and sex-specific changes to adult longevity, development speed, and mass in response to increasing concentrations of imidacloprid. These results suggest that chronic exposure to nesting substrates contaminated with neonicotinoids may represent an important route of exposure that could have considerable physiological and ecological consequences for bees and plant-pollinator interactions.

Microbialites are microbial communities that create a carbonate structure. They are abundant in the Great Salt Lake, a hypersaline lake in the arid Great Basin of the USA, where they contribute to overall primary production, seasonally up to 55%. While the microbial diversity of microbialites has been investigated, how abiotic factors affect the abundance of their primary constituents is not well understood. We examined how microbialite primary producers respond to varying levels of temperature, salinity, and nitrogen within ranges observed in the Great Salt Lake. All abiotic factors and their interactions significantly affected the maximum chlorophyll-a abundance, suggesting that these factors co-limit microbialite primary producers in the Great Salt Lake. Maximum chlorophyll-a concentrations increased with nitrogen additions and showed a parabolic relationship with salinity and temperature with peaks around 60 ppt and 20°C, respectively. While salinity had a strong effect on microbialite primary producers, we found that temperature and nitrogen were more impactful, accounting for 40 and 30% of the variance in maximum abundance, respectively, while salinity contributed just 15%. Our results show the importance of the interplay of abiotic factors on Great Salt Lake microbialites and highlight the need for increased study of benthic communities in inland saline lakes.

Alcohol abuse among college students continues to be a large societal problem in need of further study. This project investigated the influence of different types of negative repetitive thought (NRT) on alcohol use and binging behavior among undergraduates. Specifically, angry rumination, depressive rumination, co-rumination, and worry were examined. An initial exploratory factor analysis supported the distinctiveness of these four forms of NRT. With respect to quantity of weekly drinking, worry was significantly associated with less alcohol use among drinkers whereas angry rumination was associated with greater weekly usage. The effect of co-rumination was moderated by sex such that higher levels of co-rumination was associated with less weekly drinking in men but more weekly drinking in women. The tendency to co-ruminate was also significantly associated with of being a binge drinker, and demonstrated similar gender moderation. Higher levels of worry were associated with less binge drinking among women, but no association between worry and binging was present among men. The implications for these findings in the study of NRT and alcohol use are discussed.

ContextPersistence of organisms in fragmented landscapes often depends on the ability of individuals to move between habitat patches. This movement can be limited by variables of the species, patch, and/or matrix, but we often lack a comprehensive understanding of the relative importance of each of the variables and their interactions. As central place foragers, bees need to move to access resources, but we have a poor understanding of what impacts their movement in fragmented landscapes. This lack of information affects conservation efforts.ObjectivesThe primary objective was to understand the effects of species, patch, and matrix variables on bee movement between habitat patches.MethodsUsing the naturally fragmented Ozark Mountain glade ecosystem (Missouri, USA), we marked over 4500 bees in 2017 and 2018. Recapture took place 24 h later. Species, patch, and matrix variables were measured or classified including nesting location, bee size class, distance between patches, nesting resources, canopy cover, and floral resources. Principal components were used for patch and some matrix resource variables in models.ResultsOnly 8% of recaptured marked bees moved between habitat patches. Increased movement was observed for larger bees and shorter distances between patches. Bees moved up resource gradients to more rewarding patches unless the matrix provided supplementary resources.ConclusionsThough bees are often considered highly mobile and able to use nearby habitat patches, the rarity of movement in this natural system highlights the importance of patch and nearby matrix resources for supporting bee communities. While many recent studies have emphasized the species, patch, and matrix variables that may influence bee movement, the overall lack of movement even across high variability in these traits suggests conservation should not expect connectivity to help maintain community diversity.

The primary goal of the present study was to examine whether avoidance and intolerance of uncertainty predict depression and anxiety through rumination over a two week time period. Results indicated that cognitive, behavioral, and experiential avoidance all individually predicted depressive and anxious symptoms over two weeks. Cognitive, behavioral, and experiential avoidance all predicted rumination one week later. Intolerance of uncertainty predicted higher levels of anxiety and depression but not rumination. No evidence emerged that rumination acted as a mechanism of action between any of the hypothesized mediational models for depressive symptoms. Only the cognitive and experiential avoidance mediational models indicated mediation for anxiety.

Generalized Anxiety Disorder (GAD) has been described as the \"basic\" anxiety disorder. This conceptualization stems from its early onset, chronic course, and resistance to change. This view is also based on studies showing that GAD onset may temporally precede the onset of other disorders. It has also led to some speculation that GAD is a disorder from which other emotional disorders may emerge (Brown, Barlow, & Liebowitz, 1994). This review will first provide a description of GAD and its primary diagnostic criteria as well as data on the epidemiology of GAD. Next we will review the theories of etiology for the disorder. Following this, we will discuss the psychophysiological, cognitive, information processing, personality, and emotional processing features found in persons with GAD. Finally, we will conclude with a discussion of the treatment outcome studies and studies identifying predictors of treatment outcome that have been conducted on GAD individuals. El Trastorno de Ansiedad Generalizada (TAG) ha sido descrito como el trastorno de ansiedad \"básico\". Esta conceptualización surge por su temprana aparición, la cronicidad de su curso, y la resistencia al cambio. Esta visión también está basada en los estudios que muestran que la aparición del TAG puede temporalmente preceder la aparición de otros trastornos. También ha llevado a ciertas especulaciones, como por ejemplo que el TAG es un trastorno del cual pueden emerger otros trastornos emocionales (Brown, Barlow, y Liebowitz, 1994). En esta revisión se proporcionará primero una descripción del TAG y sus criterios diagnósticos principales así como datos sobre su epidemiología. Luego se revisarán las teorías etiológicas del trastorno. También se discutirán los aspectos psicofisiológicos, cognitivos, el procesamiento de información, la personalidad y los rasgos del procesamiento emotivo encontrados en personas con TAG. Finalmente, se concluye con una discusión acerca de los estudios de resultados de tratamientos y sobre la identificación de predictores de los resultados de tratamiento que se han realizado en individuos con TAG.

Secondary progressive multiple sclerosis, for which no satisfactory treatment presently exists, accounts for most of the disability in patients with multiple sclerosis. Simvastatin, which is widely used for treatment of vascular disease, with its excellent safety profile, has immunomodulatory and neuroprotective properties that could make it an appealing candidate drug for patients with secondary progressive multiple sclerosis. We undertook a double-blind, controlled trial between Jan 28, 2008, and Nov 4, 2011, at three neuroscience centres in the UK. Patients aged 18–65 years with secondary progressive multiple sclerosis were randomly assigned (1:1), by a centralised web-based service with a block size of eight, to receive either 80 mg of simvastatin or placebo. Patients, treating physicians, and outcome assessors were masked to treatment allocation. The primary outcome was the annualised rate of whole-brain atrophy measured from serial volumetric MRI. Analyses were by intention to treat and per protocol. This trial is registered with ClinicalTrials.gov, number NCT00647348. 140 participants were randomly assigned to receive either simvastatin (n=70) or placebo (n=70). The mean annualised atrophy rate was significantly lower in patients in the simvastatin group (0·288% per year [SD 0·521]) than in those in the placebo group (0·584% per year [0·498]). The adjusted difference in atrophy rate between groups was −0·254% per year (95% CI −0·422 to −0·087; p=0·003); a 43% reduction in annualised rate. Simvastatin was well tolerated, with no differences between the placebo and simvastatin groups in proportions of participants who had serious adverse events (14 [20%] vs nine [13%]). High-dose simvastatin reduced the annualised rate of whole-brain atrophy compared with placebo, and was well tolerated and safe. These results support the advancement of this treatment to phase 3 testing. The Moulton Foundation [charity number 1109891], Berkeley Foundation [268369], the Multiple Sclerosis Trials Collaboration [1113598], the Rosetrees Trust [298582] and a personal contribution from A Pidgley, UK National Institute of Health Research (NIHR) University College London Hospitals/UCL Biomedical Research Centres funding scheme.

Coral bleaching occurs when stressful conditions result in the expulsion of the algal partner from the coral. Before anthropogenic climate warming, such events were relatively rare, allowing for recovery of the reef between events. Hughes et al. looked at 100 reefs globally and found that the average interval between bleaching events is now less than half what it was before. Such narrow recovery windows do not allow for full recovery. Furthermore, warming events such as El Niño are warmer than previously, as are general ocean conditions. Such changes are likely to make it more and more difficult for reefs to recover between stressful events. Science , this issue p. 80 Coral reefs in the present day have less time than in earlier periods to recover from bleaching events. Tropical reef systems are transitioning to a new era in which the interval between recurrent bouts of coral bleaching is too short for a full recovery of mature assemblages. We analyzed bleaching records at 100 globally distributed reef locations from 1980 to 2016. The median return time between pairs of severe bleaching events has diminished steadily since 1980 and is now only 6 years. As global warming has progressed, tropical sea surface temperatures are warmer now during current La Niña conditions than they were during El Niño events three decades ago. Consequently, as we transition to the Anthropocene, coral bleaching is occurring more frequently in all El Niño–Southern Oscillation phases, increasing the likelihood of annual bleaching in the coming decades.

Recent studies have revealed the mutational signatures underlying the somatic evolution of cancer, and the prevalences of associated somatic genetic variants. Here we estimate the intensity of positive selection that drives mutations to high frequency in tumors, yielding higher prevalences than expected on the basis of mutation and neutral drift alone. We apply this approach to a sample of 525 head and neck squamous cell carcinoma exomes, producing a rank-ordered list of gene variants by selection intensity. Our results illustrate the complementarity of calculating the intensity of selection on mutations along with tallying the prevalence of individual substitutions in cancer: while many of the most prevalently-altered genes were heavily selected, their relative importance to the cancer phenotype differs from their prevalence and from their P value, with some infrequent variants exhibiting evidence of strong positive selection. Furthermore, we extend our analysis of effect size by quantifying the degree to which mutational processes (such as APOBEC mutagenesis) contributes mutations that are highly selected, driving head and neck squamous cell carcinoma. We calculate the substitutions caused by APOBEC mutagenesis that make the greatest contribution to cancer phenotype among patients. Lastly, we demonstrate via in vitro biochemical experiments that the APOBEC3B protein can deaminate the cytosine bases at two sites whose mutant states are subject to high net realized selection intensities—PIK3CA E545K and E542K. By quantifying the effects of mutations, we deepen the molecular understanding of carcinogenesis in head and neck squamous cell carcinoma.

Solid organs transport fluids through distinct vascular networks that are biophysically and biochemically entangled, creating complex three-dimensional (3D) transport regimes that have remained difficult to produce and study. We establish intravascular and multivascular design freedoms with photopolymerizable hydrogels by using food dye additives as biocompatible yet potent photoabsorbers for projection stereolithography. We demonstrate monolithic transparent hydrogels, produced in minutes, comprising efficient intravascular 3D fluid mixers and functional bicuspid valves. We further elaborate entangled vascular networks from space-filling mathematical topologies and explore the oxygenation and flow of human red blood cells during tidal ventilation and distension of a proximate airway. In addition, we deploy structured biodegradable hydrogel carriers in a rodent model of chronic liver injury to highlight the potential translational utility of this materials innovation.