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541.
Members of the bacterial candidate phylum WPS-2 (or Eremiobacterota) are abundant in several dry, bare soil environments. In a bare soil deposited by an extinct iron–sulfur spring, we found that WPS-2 comprised up to 24% of the bacterial community and up to 108 cells per g of soil based on 16S rRNA gene sequencing and quantification. A single genus-level cluster (Ca. Rubrimentiphilum) predominated in bare soils but was less abundant in adjacent forest. Nearly complete genomes of Ca. Rubrimentiphilum were recovered as single amplified genomes (SAGs) and metagenome-assembled genomes (MAGs). Surprisingly, given the abundance of WPS-2 in bare soils, the genomes did not indicate any capacity for autotrophy, phototrophy, or trace gas metabolism. Instead, they suggest a predominantly aerobic organoheterotrophic lifestyle, perhaps based on scavenging amino acids, nucleotides, and complex oligopeptides, along with lithotrophic capacity on thiosulfate. Network analyses of the entire community showed that some species of Chloroflexi, Actinobacteria, and candidate phylum AD3 (or Dormibacterota) co-occurred with Ca. Rubrimentiphilum and may represent ecological or metabolic partners. We propose that Ca. Rubrimentiphilum act as efficient heterotrophic scavengers. Combined with previous studies, these data suggest that the phylum WPS-2 includes bacteria with diverse metabolic capabilities.  相似文献   
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We have developed, and herein describe, a simple, open-loop model in the rat, in which both skin and hypothalamic temperatures can be modified and clamped. A water-perfused thermode was positioned in the abdomen to drive hypothalamic temperature, and a water-perfused jacket was used to clamp skin temperature. These permitted the independent control of hypothalamic and skin temperatures. The former could be altered between 35 and 41 °C whilst achieving an isothermal skin temperature clamp. Similarly, skin temperature could be modified between 22 and 42 °C whilst hypothalamic temperature was clamped. Maximal hypothalamic heating and cooling rates were: 0.75 and −2.04 °C h−1 100 g−1. We are currently using this animal model to investigate how central thermosensitivity is affected via manipulations of hypothalamic cooling rates.  相似文献   
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Due to total hip replacement (THR), patients reveal abnormal gait patterns which post-operative do often not return to “normal”. The restoration towards normal gait reduces stress on the adjacent joints which consequently reduces risk of osteoarthrosis development. Motor-performance is related to the structure of the movement in long-term memory, thus it seems to be essential to imprint correct gait patterns in there. Mental representation structures can develop over the course of training and visual feedback presumably helps regaining a better representation of gait in long-term memory. The purpose of this study is to evaluate the effect of visual feedback on mental representation in patients with THR. In a randomized controlled trial, 20 women (57 ± 6 years) with THR have been enrolled. Subjects were randomly assigned to a control group (CG) or intervention group (IG). Additionally to inpatient treatment, all subjects participated in a standardized gait training including either an intervention based on verbal information from a physiotherapist (CG) or an intervention based on real-time visual feedback (IG). Mental representation was measured in pre-test and post-test using the structure-dimensional analysis. Results indicate significant improvements in mental representation of gait in the post-test only in IG, suggesting that beneficial effects were provoked by visual feedback.  相似文献   
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In‐person academic conferences are important to disseminate research and provide networking opportunities. Whether academics attend in‐person conferences is based on the cost, accessibility, and safety of the event. Therefore, in‐person conferences are less accessible to academics and stakeholders that are unable to overcome some of these factors, which then act as a barrier to equal and inclusive participation. Additionally, the carbon footprint of conference travel is increasingly becoming a factor in deciding on whether to attend a conference. Online conferences may provide opportunities to mitigate these challenges. Here, we illustrate how a learned society can move their conference online. Then, comparing data acquired from the virtual conference and previous in‐person conferences, we explore the aids and barriers influencing the decision of delegates to attend the meetings. Ultimately, moving meetings online aids delegate participation by removing concerns about travel, cost, and carbon emissions, but there remains a barrier to participation as online meetings are perceived as less effective for networking and social opportunities.  相似文献   
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Summary Naturally occurring neuronal cell death has been investigated in the electromotor system of Torpedo marmorata and compared with neuronal death seen in expiant cultures of tissues from T. marmorata electric lobe. One objective of the study was to determine whether cell death in vitro was morphologically the same as cell death in vivo and to substantiate the validity of using in vitro models for studying naturally occurring cell death. Sequences of degeneration in vitro and in vivo have been established and compared: a single morphological sequence best represents this form of cell death in both conditions. In vivo, dying neurons are seen at all depths of the electric lobe indicating the involvement of different generations. Retrograde degeneration appears to be the first sign of cell death.  相似文献   
548.
By 2100, greenhouse gases are predicted to reduce ozone and cloud cover over the tropics causing increased exposure of organisms to harmful ultraviolet-B radiation (UVBR). UVBR damages DNA and is an important modulator of immune function and disease susceptibility in humans and other vertebrates. The effect of UVBR on invertebrate immune function is largely unknown, but UVBR together with ultraviolet-A radiation impairs an insect immune response that utilizes melanin, a pigment that also protects against UVBR-induced DNA damage. If UVBR weakens insect immunity, then it may make insect disease vectors more susceptible to infection with pathogens of socioeconomic and public health importance. In the tropics, where UVBR is predicted to increase, the mosquito-borne dengue virus (DENV), is prevalent and a growing threat to humans. We therefore examined the effect of UVBR on the mosquito Aedes aegypti, the primary vector for DENV, to better understand the potential implications of increased tropical UVBR for mosquito-borne disease risk. We found that exposure to a UVBR dose that caused significant larval mortality approximately doubled the probability that surviving females would become infected with DENV, despite this UVBR dose having no effect on the expression of an effector gene involved in antiviral immunity. We also found that females exposed to a lower UVBR dose were more likely to have low fecundity even though this UVBR dose had no effect on larval size or activity, pupal cuticular melanin content, or adult mass, metabolic rate, or flight capacity. We conclude that future increases in tropical UVBR associated with anthropogenic global change may have the benefit of reducing mosquito-borne disease risk for humans by reducing mosquito fitness, but this benefit may be eroded if it also makes mosquitoes more likely to be infected with deadly pathogens.  相似文献   
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An ethnobiological study concerning the medical ethnobotany and ethnozoology of two neighbouring communities of Serbians and Albanians living in the Pešter plateau (south-western Serbia) was conducted, the latter representing a diasporic community that immigrated to the area approximately three centuries ago. Sixty-two botanical taxa used in 129 plant-based remedies and 204 folk plant uses were recorded. In addition, 31 animal-derived remedies and 27 mineral or non-indigenous products were also documented. Approximately half of the recorded phytotherepeutical uses have been recorded for the first time in the ethnobotany of the Western Balkans and more than one-third of these uses have no correlation with Western evidence-based phytotherapy. Moreover, while both communities use approximately the same number of medicinal plants, two-thirds of the botanical taxa, but only one-third of plant folk medical uses are found in common among the two communities. These findings demonstrate that the two communities, although having lived in close proximity to each other during the past three centuries and in a relatively low biodiverse environment, have maintained or developed unique phytotherapeutical trajectories. The differences between the two folk medical biologies of these communities are reflective of the specific history of the Albanian diaspora, and of the complex processes of its cultural adaptation over the last three centuries.  相似文献   
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