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A synthesis of benzo[d]oxazoles by an N-deprotonation–O-SNAr cyclization sequence from anilide precursors is reported. Anilides derived from 2-fluorobenzaldehydes, activated toward SNAr ring closure by C5 electron-withdrawing groups, were prepared and subjected to deprotonation–cyclization using 2 equiv. of K2CO3 in anhydrous DMF. Following deprotonation at nitrogen, the delocalized anion cyclized from the amide oxygen to give high yields of benzo[d]oxazoles. The temperature required for the cyclization of benzanilides correlated with the potency of the C5 activating group on the SNAr acceptor ring with nitro (most potent) reacting at 90 °C (1 h), cyano reacting at 115 °C (1 h), methoxycarbonyl reacting at 120 °C (2 h), and trifluoromethyl (least potent) reacting at 130 °C (3 h). Acetanilides were more difficult to cyclize but generally required 4–6 h at these same temperatures for completion. Product purification was accomplished by recrystallization or chromatography.

Abstract Honey bee colony management is critical to mitigating the negative effects of biotic and abiotic stressors. However, there is significant variation in the practices implemented by beekeepers, which results in varying management systems. This longitudinal study incorporated a systems approach to experimentally test the role of three representative beekeeping management systems (conventional, organic, and chemical-free) on the health and productivity of stationary honey-producing colonies over 3 years. We found that the survival rates for colonies in the conventional and organic management systems were equivalent, but around 2.8 times greater than the survival under chemical-free management. Honey production was also similar, with 102% and 119% more honey produced in conventional and organic management systems, respectively, than in the chemical-free management system. We also report significant differences in biomarkers of health including pathogen levels (DWV, IAPV, Vairimorpha apis, Vairimorpha ceranae) and gene expression (def-1, hym, nkd, vg). Our results experimentally demonstrate that beekeeping management practices are key drivers of survival and productivity of managed honey bee colonies. More importantly, we found that the organic management system—which uses organic-approved chemicals for mite control—supports healthy and productive colonies, and can be incorporated as a sustainable approach for stationary honey-producing beekeeping operations.

Abstract Wild bees form diverse communities that pollinate plants in both native and agricultural ecosystems making them both ecologically and economically important. The growing evidence of bee declines has sparked increased interest in monitoring bee community and population dynamics using standardized methods. Here, we studied the dynamics of bee biodiversity within and across years by monitoring wild bees adjacent to four apple orchard locations in Southern Pennsylvania, USA. We collected bees using passive Blue Vane traps continuously from April to October for 6 years (2014–2019) amassing over 26,000 bees representing 144 species. We quantified total abundance, richness, diversity, composition, and phylogenetic structure. There were large seasonal changes in all measures of biodiversity with month explaining an average of 72% of the variation in our models. Changes over time were less dramatic with years explaining an average of 44% of the variation in biodiversity metrics. We found declines in all measures of biodiversity especially in the last 3 years, though additional years of sampling are needed to say if changes over time are part of a larger trend. Analyses of population dynamics over time for the 40 most abundant species indicate that about one third of species showed at least some evidence for declines in abundance. Bee family explained variation in species‐level seasonal patterns but we found no consistent family‐level patterns in declines, though bumble bees and sweat bees were groups that declined the most. Overall, our results show that season‐wide standardized sampling across multiple years can reveal nuanced patterns in bee biodiversity, phenological patterns of bees, and population trends over time of many co‐occurring species. These datasets could be used to quantify the relative effects that different aspects of environmental change have on bee communities and to help identify species of conservation concern.

A synthesis of benzo[d]oxazoles by an N-deprotonation–O-SNAr cyclization sequence from anilide precursors is reported. Anilides derived from 2-fluorobenzaldehydes, activated toward SNAr ring closure by C5 electron-withdrawing groups, were prepared and subjected to deprotonation–cyclization using 2 equiv. of K2CO3 in anhydrous DMF. Following deprotonation at nitrogen, the delocalized anion cyclized from the amide oxygen to give high yields of benzo[d]oxazoles. The temperature required for the cyclization of benzanilides correlated with the potency of the C5 activating group on the SNAr acceptor ring with nitro (most potent) reacting at 90 °C (1 h), cyano reacting at 115 °C (1 h), methoxycarbonyl reacting at 120 °C (2 h), and trifluoromethyl (least potent) reacting at 130 °C (3 h). Acetanilides were more difficult to cyclize but generally required 4–6 h at these same temperatures for completion. Product purification was accomplished by recrystallization or chromatography. [ABSTRACT FROM AUTHOR]

Bee monitoring, or widespread efforts to document bee community biodiversity, can involve data collection using lethal (specimen collections) or non-lethal methods (observations, photographs). Additionally, data can be collected by professional scientists or by volunteer participants from the general public. Collection-based methods presumably produce more reliable data with fewer biases against certain taxa, while photography-based approaches, such as data collected from public natural history platforms like iNaturalist, can involve more people and cover a broader geographic area. Few efforts have been made to quantify the pros and cons of these different approaches. We established a community science monitoring program to assess bee biodiversity across the state of Pennsylvania (USA) using specimen collections with nets, blue vane traps, and bowl traps. We recruited 26 participants, mostly Master Gardeners, from across the state to sample bees after receiving extensive training on bee monitoring topics and methods. The specimens they collected were identified to species, stored in museum collections, and the data added to public databases. Then, we compared the results from our collections to research-grade observations from iNaturalist during the same time period (2021 and 2022). At state and county levels, we found collections data documented over twice as much biodiversity and novel baseline natural history data (state and county records) than data from iNaturalist. iNaturalist data showed strong biases toward large-bodied and non-native species. This study demonstrates the value of highly trained community scientists for collections-based research that aims to document patterns of bee biodiversity over space and time. [ABSTRACT FROM AUTHOR]

Abstract Soft robots typically involve manual assembly of core hardware components like actuators, sensors, and controllers. This increases fabrication time and reduces consistency, especially in small-scale soft robots. We present a scalable monolithic fabrication method for millimeter-scale soft-rigid hybrid robots, simplifying the integration of core hardware components. Actuation is provided by soft-foldable polytetrafluoroethylene film-based actuators powered by ionic fluid injection. The desired motion is encoded by integrating a mechanical controller, comprised of rigid-flexible materials. The robot’s motion can be self-sensed using an ionic resistive sensor by detecting electrical resistance changes across its body. Our approach is demonstrated by fabricating three distinct soft-rigid hybrid robotic modules, each with unique degrees of freedom: translational, bending, and roto-translational motions. These modules connect to form a soft-rigid hybrid continuum robot with real-time shape-sensing capabilities. We showcase the robot’s capabilities by performing object pick-and-place, needle steering and tissue puncturing, and optical fiber steering tasks.

The Mars 2020/Mars Sample Return (MSR) Sample Depot Science Community Workshop was held on September 28 and 30, 2022, to assess the Scientifically‐Return Worthy (SRW) value of the full collection of samples acquired by the rover Perseverance at Jezero Crater, and of a proposed subset of samples to be left as a First Depot at a location within Jezero Crater called Three Forks. The primary outcome of the workshop was that the community is in consensus on the following statement: The proposed set of ten sample tubes that includes seven rock samples, one regolith sample, one atmospheric sample, and one witness tube constitutes a SRW collection that: (1) represents the diversity of the explored region around the landing site, (2) covers partially or fully, in a balanced way, all of the International MSR Objectives and Samples Team scientific objectives that are applicable to Jezero Crater, and (3) the analyses of samples in this First Depot on Earth would be of fundamental importance, providing a substantial improvement in our understanding of Mars. At the conclusion of the meeting, there was overall community support for forming the First Depot as described at the workshop and placing it at the Three Forks site. The community also recognized that the diversity of the Rover Cache (the sample collection that remains on the rover after placing the First Depot) will significantly improve with the samples that are planned to be obtained in the future by the Perseverance rover and that the Rover Cache is the primary target for MSR to return to Earth. [ABSTRACT FROM AUTHOR]

Today's biology educators face the challenge of training their students in modern molecular biology techniques including genomics and bioinformatics. The Dolan DNA Learning Center (DNALC) of Cold Spring Harbor Laboratory has developed and disseminated a bench- and computer-based plant genomics curriculum for biology faculty. In 2007, a five-day "Plant Genomics and Gene Annotation" workshop was held at Florida A&M University in Tallahassee, FL, to enhance participants' knowledge and understanding of plant molecular genetics and assist them in developing and honing their laboratory and computer skills. Florida A&M University is a historically black university with over 95% African-American student enrollment. Sixteen participants, including high school (56%) and community college faculty (25%), attended the workshop. Participants carried out in vitro and in silico experiments with maize, "Arabidopsis", soybean, and food products to determine the genotype of the samples. Benefits of the workshop included increased awareness of plant biology research for high school and college level students. Participants completed pre- and postworkshop evaluations for the measurement of effectiveness. Participants demonstrated an overall improvement in their postworkshop evaluation scores. This article provides a detailed description of workshop activities, as well as assessment and long-term support for broad classroom implementation. (Contains 2 figures and 4 tables.)

Plant-fungal endophyte interactions are common in nature and they can shape the ecology of plants. Vertically transmitted endophytes are hypothesized to serve as mutualists, protecting plants from herbivores. If this hypothesis is true, then we expect endophytes to be most abundant in the presence of herbivores and least abundant in their absence, assuming endophytes incur a cost to their host. We tested this prediction by studying the effects of intense rabbit (Oryctolagus cuniculus Linnaeus) grazing on grass-endophyte interactions at Silwood Park, UK. We examined seeds of red fescue (Festuca rubra L.) collected from 15 natural populations that were protected from rabbits for 0.3-21 years. Contrary to our prediction, the mean proportion of seeds with endophytes increased 1.84x, from 0.45 to 0.83, following 21 years of rabbit exclusion. To better understand the mechanisms driving this increase in frequency, we conducted a fully factorial greenhouse experiment where we manipulated the presence or absence of endophyte infection, intraspecific competition, and simulated grazing on F. rubra plants. In both damaged and undamaged treatments, infected plants produced approximately twice as much biomass as uninfected plants, and endophytes did not influence tolerance to herbivory. These results suggest that endophytes directly change plant growth but not compensatory responses to damage. In the absence of competitors, infected plants produced 2.17x more biomass than uninfected plants, whereas in the presence of competitors, infected plants produced only 1.55x more biomass than uninfected plants. This difference suggests that intraspecific competition might lessen the benefits of endophyte infection. Our results do not support the defensive mutualism hypothesis, but instead suggest that endophyte-induced plant growth is important in shaping the costs and benefits of endophytes in our system. Key words: defensive mutualism hypothesis, herbivory, grassland, plant-fungal, plant-animal, Epichloefestucae. Les interactions plante--endophyte fongique sont frequentes dans la nature et elles peuvent faconner l'ecologie des vegetaux. Les endophytes transmis de maniere verticale sont presumes servir d'organismes mutualistes, protegeant les vegetaux des herbivores. Si cette hypothese s'avere, on peut consequemment s'attendre a ce que les endophytes soient plus abondants en presence d'herbivores et moins abondants en leur absence, assumant que les endophytes engagent un cout pour leur hote. Les auteurs ont teste cette prediction en etudiant les effets d'un broutage intense par le lapin (Oryctolagus cuniculus Linnaeus) sur les interactions herbes-endophytes a Silkwood Park, RU. Ils ont examine les graines de la fetuque rouge (Festuca rubra L.) recueillies de 15 populations naturelles protegees des lapins pendant 0,3-21 ans. Contrairement a leur prediction, la proportion moyenne de graines comprenant des endophytes augmentait de 1,84x, de 0,45 a 0,83, apres avoir exclu les lapins pendant 21 ans. Afin de mieux comprendre les mecanismes responsables de cette augmentation de la frequence, les auteurs ont realise des experiences factorielles completes en serres, oU ils ont manipule la presence ou l'absence d'infection par les endophytes, la competition intraspecifique et le broutage simule des plants de F. rubra. Dans les cas de traitements dommageables ou non, les plants infectes produisaient approximativement deux fois plus de biomasse que les plants non infectes, et les endophytes n'influencaient pas la tolerance a l'herbivorisme. Ces resultats suggerent que les endophytes changent directement la croissance des vegetaux mais pas les reponses compensatoires au dommage. En absence de competiteurs, les plants infectes produisaient 2,17x plus de biomasse que les plants non infectes, alors qu'en presence de competiteurs, les plants infectes produisaient seulement 1,55x plus de biomasse que les plants non infectes. Cette difference suggere que la competition intraspecifique peut amoindrir les benefices conferes par l'infection par des endophytes. Les resultats des auteurs n'appuient par l'hypothese du mutualisme defensif, mais suggerent plutot que la croissance de la plante induite par les endophytes est importante pour faconner les couts et les benefices des endophytes dans leur systeme. [Traduit par la Redaction] Mots-cles: hypothese du mutualisme defensif, herbivorisme, prairie, plante-champignon, plante-animal, Epichloefestucae., Introduction Plant-microbe interactions are ubiquitous in nature and play pivotal roles in shaping plant ecology and evolution (Yang et al. 2013). Microbial symbionts, both bacterial and fungal, can shape plant [...]

Background: Studies of sexually transmitted infections (STI) apart from HIV are lacking among transgender women in the United States. This paucity of information has limited guidance on testing and prevention [...]