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121.
Jamie Alison Jake M. Alexander Nathan Diaz Zeugin Yoko L. Dupont Evelin Iseli Hjalte M. R. Mann Toke T. Hye 《Biology letters》2022,18(7)
Recent decades have seen a surge in awareness about insect pollinator declines. Social bees receive the most attention, but most flower-visiting species are lesser known, non-bee insects. Nocturnal flower visitors, e.g. moths, are especially difficult to observe and largely ignored in pollination studies. Clearly, achieving balanced monitoring of all pollinator taxa represents a major scientific challenge. Here, we use time-lapse cameras for season-wide, day-and-night pollinator surveillance of Trifolium pratense (L.; red clover) in an alpine grassland. We reveal the first evidence to suggest that moths, mainly Noctua pronuba (L.; large yellow underwing), pollinate this important wildflower and forage crop, providing 34% of visits (bumblebees: 61%). This is a remarkable finding; moths have received no recognition throughout a century of T. pratense pollinator research. We conclude that despite a non-negligible frequency and duration of nocturnal flower visits, nocturnal pollinators of T. pratense have been systematically overlooked. We further show how the relationship between visitation and seed set may only become clear after accounting for moth visits. As such, population trends in moths, as well as bees, could profoundly affect T. pratense seed yield. Ultimately, camera surveillance gives fair representation to non-bee pollinators and lays a foundation for automated monitoring of species interactions in future. 相似文献
122.
The molecular mechanisms of toxicity associated with cytoplasmic accumulation of TAR DNA binding protein-43(TDP-43),a pathological feature of many neurodegenera... 相似文献
123.
124.
Guigal N Rodriguez M Cooper RN Dromaint S Di Santo JP Mouly V Boutin JA Galizzi JP 《The Journal of biological chemistry》2002,277(49):47407-47411
Uncoupling protein-3 (UCP3), which is expressed abundantly in skeletal muscle, is one of the carrier proteins dissipating the transmitochondrial electrochemical gradient as heat and has therefore been implicated in the regulation of energy metabolism. Myoblasts or differentiated muscle cells in vitro expressed little if any UCP3, compared with the levels detected in biopsies of skeletal muscle. In the present report, we sought to investigate UCP3 mRNA expression in human muscle generated by myoblast transplantation in the skeletal muscle of an immunodeficient mouse model. Time course experiments demonstrated that 7-8 weeks following transplantation fully differentiated human muscle fibers were formed. The presence of differentiated human muscle fibers was assessed by quantitative PCR measurement of the human alpha-actin mRNA together with immunohistochemical staining using specific antibodies for spectrin and the slow adult myosin heavy chain. Interestingly, we found that the expression of UCP3 mRNA was dependant on human muscle differentiation and that the UCP3 mRNA level was comparable with that found in human muscle biopsies. Moreover, the human UCP3 (hUCP3) promoter seems to be fully functional, since triiodothyronine treatment of the mice not only stimulated the mouse UCP3 (mUCP3) mRNA expression but also strongly stimulated the hUCP3 mRNA expression in human fibers formed after myoblast transplantation. To our knowledge, this is the first time that primary myoblasts could be induced to express the UCP3 gene at a level comparable of that found in human muscle fibers. 相似文献
125.
Future coral reefs are expected to be subject to higher pCO2 and temperature due to anthropogenic greenhouse gas emissions. Such global stressors are often paired with local stressors thereby potentially modifying the response of organisms. Benthic macroalgae are strong competitors to corals and are assumed to do well under future conditions. The present study aimed to assess the impact of past and future CO2 emission scenarios as well as nutrient enrichment on the growth, productivity, pigment, and tissue nutrient content of the common tropical brown alga Chnoospora implexa. Two experiments were conducted to assess the differential impacts of the manipulated conditions in winter and spring. Chnoospora implexa's growth rate averaged over winter and spring declined with increasing pCO2 and temperature. Furthermore, nutrient enrichment did not affect growth. Highest growth was observed under spring pre‐industrial (PI) conditions, while slightly reduced growth was observed under winter A1FI (“business‐as‐usual”) scenarios. Productivity was not a good proxy for growth, as net O2 flux increased under A1FI conditions. Nutrient enrichment, whilst not affecting growth, led to luxury nutrient uptake that was greater in winter than in spring. The findings suggest that in contrast with previous work, C. implexa is not likely to show enhanced growth under future conditions in isolation or in conjunction with nutrient enrichment. Instead, the results suggest that greatest growth rates for this species appear to be a feature of the PI past, with A1FI winter conditions leading to potential decreases in the abundance of this species from present day levels. 相似文献
126.
127.
Françoise Simon-Plas Kees Venema Jean-Pierre Grouzis Rémy Gibrat Jacqueline Rigaud Claude Grignon 《The Journal of membrane biology》1991,120(1):51-58
Summary The purified (H+ATPase from corn roots plasma membrane inserted spontaneously into preformed bilayer from soybean lipids. The yield of the protein insertion, as measured from its H+-pumping activity, increased as a function of lipids and protein concentrations. In optimum conditions, all the (H+)ATPase molecules were closely associated with liposomes, exhibiting a high H+-pumping activity (150,000% quenching· min–1·mg–1 protein of the probe 9-amino-6-chloro-2-methoxyacridine). The insertion was achieved within a few seconds. No latency of the (H+)ATPase hydrolytic activity was revealed when lysophosphatidylcholine was added to permeabilize the vesicles. This indicated that the (H+)ATPase molecules inserted unidirectionally, the catalytic sites being exposed outside the vesicles (inside-out orientation), and thus freely accessible to Mg-ATP. The nondelipidated (H+)ATPase could also functionally insert into bilayer from PCPEPG or PCPEPI, due to the presence of both hydrophobic defects promoted by PE, and negative phospholipids specifically required by the (H+)ATPase from corn roots. The detergent octylglucoside facilitated the delipidated (H+)ATPase reinsertion probably by promoting both a proper protein conformation and hydrophobic defects in the bilayer. Lysophosphatidylcholine facilitated the delipidated protein insertion only when hydrophobic defects were already present, and thus seemed only capable to ensure a proper protein conformation 相似文献
128.
Cecile Bessou Claudine Basset-Mens Cynthia Latunussa Alice Vélu Hadrien Heitz Henri Vannière Jean-Pierre Caliman 《The International Journal of Life Cycle Assessment》2016,21(3):297-310
Purpose
As highlighted in recent reviews, there is a need to harmonise the way life cycle assessment (LCA) of perennial crops is conducted. In most published LCA on perennial crops, the modelling of the agricultural production is based on data sets for just one productive year. This may be misleading since performance and impacts of the system may greatly vary year by year. The purposes of this study are to analyse how partial modelling of the perennial cycle through non-holistic data collection may affect LCA results and to make recommendations.Methods
Three modelling choices for the perennial crop cycle were tested in parallel in two contrasted LCA case studies: oil palm fruits from Indonesia, and small citrus from Morocco. Modelling choices tested were as follows: (i) a chronological modelling over the complete crop cycle of orchards, (ii) a 3-year average from the productive phase, and (iii) various single years from the productive phase. In both case studies, the system boundary was a cradle-to-farm gate with a functional unit of 1 kg fresh fruits. LCA midpoint impacts were calculated with ReCiPe 2008 in Simapro©V.7. We first analysed how inputs, yields and potential impacts varied over time. We then analysed process contributions in the baseline model, i.e. the chronological modelling, and finally compared LCA results for the various perennial modelling choices.Results and discussion
Agricultural practices, yields and impacts varied over the years especially during the first 3–9 years depending on the case study. In both case studies, the modelling choices to account or not for the whole perennial cycle drastically influenced LCA results. The differences could be explained by the inclusion or not of the yearly variability and the accounting or not of the immature phase, which contributed to 7–40 or 6.5–29 % of all impact categories for oil palm fruit and citrus, respectively.Conclusions
The chosen approach to model the perennial cycle influenced the final LCA results for two contrasted case studies and deserved specific attention. Although data availability may remain the limiting factor in most cases, assumptions can be made to interpolate or extrapolate some data sets or to consolidate data sets from chronosequences (i.e. modular modelling). In all cases, we suggest that the approach chosen to model the perennial cycle and the representativeness of associated collected data should be made transparent and discussed. Further research work is needed to improve the understanding and modelling of perennial crop functioning and LCA assessment.129.
Lateralization of olfactory processes 总被引:2,自引:0,他引:2
Over the last ten years, methods of cerebral imaging have revolutionized our knowledge of cognitive processes in humans. An impressive number of papers dealing with cerebral imaging for olfaction have been published to date. Whereas the early works revealed those structures participating in the processing of odours presented passively to subjects, researchers later recorded brain activity when subjects performed specific olfactory tasks based on memory, emotion and identification. From these results, we suggest that there is a dissociation of olfactory processes, with involvement of the right hemisphere in memory processes and the left hemisphere in emotional processes. The review concludes with a summary of how these lateralized processes are consistent with the gestalt-nature of our olfactory perception. 相似文献
130.
Shari Kiekens Dieter Vandenheuvel Géraldine Broeckx Ingmar Claes Camille Allonsius Ilke De Boeck Sofie Thys Jean-Pierre Timmermans Filip Kiekens Sarah Lebeer 《Microbial biotechnology》2019,12(5):849-855
The preservation of the viability of microorganisms in probiotic formulations is the most important parameter ensuring the adequate concentration of live microorganisms at the time of administration. The formulation and processing techniques used to produce these probiotic formulations can influence the preservation of the microbial viability. However, it is also required that the bacteria maintain their key probiotic capacities during processing, formulation and shelf life. In this study, we investigated the impact of spray-drying on different cell wall properties of the model probiotic strain Lactobacillus rhamnosus GG, including its adherence to intestinal epithelial cells. The dltD gene knock-out mutant, L. rhamnosus GG CMPG5540, displaying modified cell wall lipoteichoic acids, showed significantly increased colony-forming units after spray-drying and subsequent storage under standard conditions compared to wild-type L. rhamnosus GG. In contrast, disruption of the biosynthesis of exopolysaccharides or pili expression did not impact survival. However, spray-drying did significantly affect the adherence capacity of L. rhamnosus GG. Scanning electron microscopy confirmed that the pili, key surface factors for adherence to intestinal cells and mucus, were sheared off during the spray-drying process. These data thus highlight that both the functionality and viability of probiotics should be assessed during the spray-drying process and subsequent storage. 相似文献