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31.
Local knowledge systems are not considered in the conservation of fragile seagrass marine ecosystems. In fact, little is known about the utility of seagrasses in local coastal communities. This is intriguing given that some local communities rely on seagrasses to sustain their livelihoods and have relocated their villages to areas with a rich diversity and abundance of seagrasses. The purpose of this study is to assist in conservation efforts regarding seagrasses through identifying Traditional Ecological Knowledge (TEK) from local knowledge systems of seagrasses from 40 coastal communities along the eastern coast of India. We explore the assemblage of scientific and local traditional knowledge concerning the 1. classification of seagrasses (comparing scientific and traditional classification systems), 2. utility of seagrasses, 3. Traditional Ecological Knowledge (TEK) of seagrasses, and 4. current conservation efforts for seagrass ecosystems. Our results indicate that local knowledge systems consist of a complex classification of seagrass diversity that considers the role of seagrasses in the marine ecosystem. This fine-scaled ethno-classification gives rise to five times the number of taxa (10 species = 50 local ethnotaxa), each with a unique role in the ecosystem and utility within coastal communities, including the use of seagrasses for medicine (e.g., treatment of heart conditions, seasickness, etc.), food (nutritious seeds), fertilizer (nutrient rich biomass) and livestock feed (goats and sheep). Local communities are concerned about the loss of seagrass diversity and have considerable local knowledge that is valuable for conservation and restoration plans. This study serves as a case study example of the depth and breadth of local knowledge systems for a particular ecosystem that is in peril.  相似文献   
32.
33.
Pasteurella multocida is a highly infectious, facultative intracellular bacterium which causes fowl cholera in birds. This study reports, for the first time, the observed interaction between P. multocida and free-living amoebae. Amoebal trophozoites were coinfected with fowl-cholera-causing P. multocida strain X-73 that expressed the green fluorescent protein (GFP). Using confocal fluorescence microscopy, GFP expressing X-73 was located within the trophozoite. Transmission electron microscopy of coinfection preparations revealed clusters of intact X-73 cells in membrane-bound vacuoles within the trophozoite cytoplasm. A coinfection assay employing gentamicin to kill extracellular bacteria was used to assess the survival and replication of P. multocida within amoebae. In the presence of amoebae, the number of recoverable intracellular X-73 cells increased over a 24-h period; in contrast, X-73 cultured alone in assay medium showed a consistent decline in growth. Cytotoxicity assays and microscopy showed that X-73 was able to lyse and exit the amoebal cells approximately 18 h after coinfection. The observed interaction between P. multocida and amoebae can be considered as an infective process as the bacterium was able to invade, survive, replicate, and lyse the amoebal host. This raises the possibility that similar interactions occur in vivo between P. multocida and host cells. Free-living amoebae are ubiquitous within water and soil environments, and P. multocida has been observed to survive within these same ecosystems. Thus, our findings suggest that the interaction between P. multocida and amoebae may occur within the natural environment.  相似文献   
34.

Background

The aim of this study, conducted in Europe, was to develop a validated risk factor based model to predict RSV-related hospitalisation in premature infants born 33–35 weeks'' gestational age (GA).

Methods

The predictive model was developed using risk factors captured in the Spanish FLIP dataset, a case-control study of 183 premature infants born between 33–35 weeks'' GA who were hospitalised with RSV, and 371 age-matched controls. The model was validated internally by 100-fold bootstrapping. Discriminant function analysis was used to analyse combinations of risk factors to predict RSV hospitalisation. Successive models were chosen that had the highest probability for discriminating between hospitalised and non-hospitalised infants. Receiver operating characteristic (ROC) curves were plotted.

Results

An initial 15 variable model was produced with a discriminant function of 72% and an area under the ROC curve of 0.795. A step-wise reduction exercise, alongside recalculations of some variables, produced a final model consisting of 7 variables: birth ± 10 weeks of start of season, birth weight, breast feeding for ≤ 2 months, siblings ≥ 2 years, family members with atopy, family members with wheeze, and gender. The discrimination of this model was 71% and the area under the ROC curve was 0.791. At the 0.75 sensitivity intercept, the false positive fraction was 0.33. The 100-fold bootstrapping resulted in a mean discriminant function of 72% (standard deviation: 2.18) and a median area under the ROC curve of 0.785 (range: 0.768–0.790), indicating a good internal validation. The calculated NNT for intervention to treat all at risk patients with a 75% level of protection was 11.7 (95% confidence interval: 9.5–13.6).

Conclusion

A robust model based on seven risk factors was developed, which is able to predict which premature infants born between 33–35 weeks'' GA are at highest risk of hospitalisation from RSV. The model could be used to optimise prophylaxis with palivizumab across Europe.  相似文献   
35.
The discovery of higher-order epistatic interactions is an important task in the field of genome wide association studies which allows for the identification of complex interaction patterns between multiple genetic markers. Some existing bruteforce approaches explore the whole space of k-interactions in an exhaustive manner resulting in almost intractable execution times. Computational cost can be reduced drastically by restricting the search space with suitable preprocessing filters which prune unpromising candidates. Other approaches mitigate the execution time by employing massively parallel accelerators in order to benefit from the vast computational resources of these architectures. In this paper, we combine a novel preprocessing filter, namely SingleMI, with massively parallel computation on modern GPUs to further accelerate epistasis discovery. Our implementation improves both the runtime and accuracy when compared to a previous GPU counterpart that employs mutual information clustering for prefiltering. SingleMI is open source software and publicly available at: https://github.com/sleeepyjack/singlemi/.  相似文献   
36.
Heterogeneity in social interactions can have important consequences for the spread of information and diseases and consequently conservation and invasive species management. Common carp (Cyprinus carpio) are a highly social, ubiquitous, and invasive freshwater fish. Management strategies targeting foraging carp may be ideal because laboratory studies have suggested that carp can learn, have individual personalities, a unique diet, and often form large social groups. To examine social feeding behaviors of wild carp, we injected 344 carp with passive integrated transponder (PIT) tags and continuously monitored their feeding behaviors at multiple sites in a natural lake in Minnesota, USA. The high‐resolution, spatio‐temporal data were analyzed using a Gaussian mixture model (GMM). Based on these associations, we analyzed group size, feeding bout duration, and the heterogeneity and connectivity of carp social networks at foraging sites. Wild carp responded quickly to bait, forming aggregations most active from dusk to dawn. During the 2020 baiting period (20 days), 133 unique carp were detected 616,593 times. There was some evidence that feeding at multiple sites was constrained by basin geography, but not distance alone. GMM results suggested that feeding bouts were short, with frequent turnover of small groups. Individual foraging behavior was highly heterogeneous with Gini coefficients of 0.79 in 2020 and 0.66 in 2019. “Superfeeders”—those contributing to 80% of total cumulative detections (top 18% and top 29% of foragers in 2020 and 2019 respectively)—were more likely to be detected earlier at feeding stations, had larger body sizes, and had higher network measures of degree, weighted degree, and betweenness than non‐superfeeders. Overall, our results indicate that wild carp foraging is social, easily induced by bait, dominated by large‐bodied individuals, and potentially predictable, which suggests social behaviors could be leveraged in management of carp, one of the world''s most recognizable and invasive fish.  相似文献   
37.
Zusammenfassung Der Braunkohlentagebau führt zu beträchtlichen Eingriffen in die Kulturlandschaft. Durch Wiederurbarmachung und Rekultivierung der Tagebauareale werden beträchtliche Bodenflächen der gesellschaftlichen Nutzung wieder zur Verfügung gestellt. In Landschaften mit von Natur aus fruchtbaren Böden steht dabei die Kippenrekultivierung für eine landwirtschaftliche Nutzung und in Gebieten mit von Natur aus weniger fruchtbaren Böden für eine forstliche Nutzung im Vordergrund. Die Tagebaurestlöcher werden häuftig zu Naherholungsgebieten umgestaltet oder für wasserwirtschaftliche Zwecke bzw. für eine geordnete Mülldeponie verwandt. In der Arbeit wird die syngenetische Entwicklung von aufgeforsteten achtjärigen Monokulturen des Populus-Artemisia vulgaris-Typs über etwa 30 jährige Bestände des Populus-Taraxacum officinale-Typs und Populus-Calamagrostis epigeios-Typs bis zu etwa 60 jährigen Baumbeständen des Populus-Carpinus betulus-Typs unter pflanzensoziologischen, ökologischen und pflanzengeographischen Aspekten untersucht. Die Arbeit schließt mit einer Darstellung der landeskulturellen Bedeutung der Kippenaufforstung für die gesamte Kulturlandschaft.
In der Untersuchung wurden Ergebnisse, darunter Vegetationstabellen der zu erwähnenden Vegetationstypen der Lehrer-Diplomarbeit von Herrn Frenzel (1976) mit einbezogen, dem wir an dieser Stelle für seine Mitarbeit recht herzlich danken möchten.  相似文献   
38.
The subunit composition of cytochrome c oxidase from rat liver mitochondria was studied by dodecylsulfate polyacrylamide gel electrophoresis. The apparent molecular weight of the seven subunits are in reasonable agreement with published data on cytochrome c oxidase subunits from other sources. Two additional subunits were found if the electrophoresis was performed with 8m urea, due to splitting of the smallest subunit. Performic acid oxidation of the isolated subunits I and II increased the apparent molecular weights from 38000 to 48000 and from 24500 to 29000, respectively, accompained by a normalization of the anomalous behaviour of subunit I in the Ferguson plot. It is suggested that performic acid, by splitting extremely inaccessible disulfide bridges, mediates full complexing of the subunits by dodecylsulfate, thus permitting the determination of the real molecular weights by dodecylsulfate polyacrylamide gel electrophoresis.  相似文献   
39.
R. Hundt 《Plant Ecology》1985,61(1-3):97-103
Foredunes, white-, grey- and brown dunes have an important function in coastal protection. Although a close syngenetic connection exists between these neighbouring ecosystems, they are considerably differentiated phytosociologically and ecologically. Whilst on foredunes and white dunes the predominating plant species are characteristic of Ammophiletea, on the grey dunes, species characteristic of the Festuco-Brometea and the Sedo-Scleranthetea are found, and on the brown dunes species of the Nardo-Callunetea.Going through the white-, grey- and brown dunes, the salt and lime content and the pH are decreasing. In grey- and brown dunes the formation of humus starts and a lower pH develops. On the grey dunes, which are sparsely vegetated, the air temperature, soil moisture, air moisture and evaporation are extremely fluctuating daily. The climate values in the brown dunes are relatively constant. There is a close connection between the ecology of the dune types and their specific function in coastal protection.Nomenclature of syntaxa follows Rothmaler (1976).  相似文献   
40.
Birt-Hogg-Dubé (BHD) syndrome is a rare autosomal dominant condition caused by mutations in the FLCN gene and characterized by benign hair follicle tumors, pneumothorax, and renal cancer. Folliculin (FLCN), the protein product of the FLCN gene, is a poorly characterized tumor suppressor protein, currently linked to multiple cellular pathways. Autophagy maintains cellular homeostasis by removing damaged organelles and macromolecules. Although the autophagy kinase ULK1 drives autophagy, the underlying mechanisms are still being unraveled and few ULK1 substrates have been identified to date. Here, we identify that loss of FLCN moderately impairs basal autophagic flux, while re-expression of FLCN rescues autophagy. We reveal that the FLCN complex is regulated by ULK1 and elucidate 3 novel phosphorylation sites (Ser406, Ser537, and Ser542) within FLCN, which are induced by ULK1 overexpression. In addition, our findings demonstrate that FLCN interacts with a second integral component of the autophagy machinery, GABA(A) receptor-associated protein (GABARAP). The FLCN-GABARAP association is modulated by the presence of either folliculin-interacting protein (FNIP)-1 or FNIP2 and further regulated by ULK1. As observed by elevation of GABARAP, sequestome 1 (SQSTM1) and microtubule-associated protein 1 light chain 3 (MAP1LC3B) in chromophobe and clear cell tumors from a BHD patient, we found that autophagy is impaired in BHD-associated renal tumors. Consequently, this work reveals a novel facet of autophagy regulation by ULK1 and substantially contributes to our understanding of FLCN function by linking it directly to autophagy through GABARAP and ULK1.  相似文献   
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