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41.
42.
A Blume K Seifert CJ Lebrun E M?llenhoff P Gass T Unger T Herdegen 《Canadian Metallurgical Quarterly》1998,241(2-3):87-90
Binding to olfactory receptors is the first step in odorant and pheromonal recognition and discrimination. These receptors constitute one of the most important, although poorly known, families of neuronal receptors. In this study we used degenerated oligonucleotides and a RT-PCR approach to selectively amplify olfactory receptors in the nasal epithelium of the domestic pig Sus scrofa. Several combinations of oligonucleotide were tested and allowed the isolation of eleven different partial sequences belonging to the seven transmembrane olfactory receptor family. These receptors formed a separate family within the seven transmembrane receptor superfamily in pigs. Using the criteria of Ben Arie et al. [Ben-Arie N., Lancet D., Taylor C., Khen M., Walker N., Ledbetter DH., Carrozzo R., Patel K., Sheer D., Lehrah H. and North M., Hum. Mol. Genet., 3 (1994) 229-235], the 11 receptors described here can be classified into three known families and seven subfamilies (one known and six new). 相似文献
43.
We propose a newO(p
3
n
2) algorithm for solving complexnp×np linear systems that have block Hankel structure, where the blocks are square matrices of sizep×p. Via FFTs the block Hankel system is transformed into a block Loewner system. An inversion formula enables us to calculate
the inverse of the block Loewner matrix explicitely. The parameters that occur in this inversion formula are calculated by
solving two rational interpolation problems on the unit circle. We have implemented our algorithm in Fortran 90. Numerical
examples are included. 相似文献
44.
Mark Olokotum Marc Troussellier Arthur Escalas Sahima Hamlaoui William Okello Ronald Semyalo Jean-François Humbert Cécile Bernard 《Journal of Great Lakes research》2021,47(4):985-996
Eutrophication of Lake Victoria led to changes in its phytoplankton communities. However, different levels of eutrophication exist in the open lake and the bays, and between embayments. This study utilized spatial and temporal sampling of Napoleon Gulf and Murchison Bay, exhibiting different trophic conditions. Over one year, we investigated phytoplankton biomass, richness, diversity and dissimilarity, and related the dynamics of the dominant species to the limnological and climatic conditions. The results confirmed that Napoleon Gulf and Murchison Bay showed large differences in eutrophication status, with lower nutrient concentrations in Napoleon Gulf than in Murchison Bay, where a strong gradient was observed from inshore to offshore areas. These nutrient dynamics resulted in a 4 to 10 fold higher chlorophyll-a in Murchison Bay than in Napoleon Gulf. From the embayments, 135 phytoplankton taxa were recorded with no significant differences in alpha diversity. However, high dissimilarity in community structure was observed in beta diversity, mostly due to a turnover among the dominant toxigenic species. Thus, from a similar species pool, there was a shift in the dominant toxigenic cyanobacteria from Microcystis flos-aquae and M. aeruginosa in Murchison Bay, Dolichospermum circinale and Planktolyngbya circumcreta in Napoleon Gulf to D. circinale in the offshore stations. These cyanobacteria are toxigenic taxa with known health hazards. Using partial least square models, we showed that both climatic variables (e.g. wind, solar radiation) and levels of inorganic dissolved nutrients (e.g. SRP, NO3–, and NH4+) are the main drivers of differences and dominance in cyanobacteria communities in northern Lake Victoria. 相似文献
45.
Streit M Schulz HJ Lex A Schmalstieg D Schumann H 《IEEE transactions on visualization and computer graphics》2012,18(6):998-1010
As heterogeneous data from different sources are being increasingly linked, it becomes difficult for users to understand how the data are connected, to identify what means are suitable to analyze a given data set, or to find out how to proceed for a given analysis task. We target this challenge with a new model-driven design process that effectively codesigns aspects of data, view, analytics, and tasks. We achieve this by using the workflow of the analysis task as a trajectory through data, interactive views, and analytical processes. The benefits for the analysis session go well beyond the pure selection of appropriate data sets and range from providing orientation or even guidance along a preferred analysis path to a potential overall speedup, allowing data to be fetched ahead of time. We illustrate the design process for a biomedical use case that aims at determining a treatment plan for cancer patients from the visual analysis of a large, heterogeneous clinical data pool. As an example for how to apply the comprehensive design approach, we present Stack'n'flip, a sample implementation which tightly integrates visualizations of the actual data with a map of available data sets, views, and tasks, thus capturing and communicating the analytical workflow through the required data sets. 相似文献
46.
Ivan Rodero Hariharasudhan Viswanathan Eun Kyung Lee Marc Gamell Dario Pompili Manish Parashar 《Journal of Grid Computing》2012,10(3):447-473
Virtualized datacenters and clouds are being increasingly considered for traditional High-Performance Computing (HPC) workloads that have typically targeted Grids and conventional HPC platforms. However, maximizing energy efficiency and utilization of datacenter resources, and minimizing undesired thermal behavior while ensuring application performance and other Quality of Service (QoS) guarantees for HPC applications requires careful consideration of important and extremely challenging tradeoffs. Virtual Machine (VM) migration is one of the most common techniques used to alleviate thermal anomalies (i.e., hotspots) in cloud datacenter servers as it reduces load and, hence, the server utilization. In this article, the benefits of using other techniques such as voltage scaling and pinning (traditionally used for reducing energy consumption) for thermal management over VM migrations are studied in detail. As no single technique is the most efficient to meet temperature/performance optimization goals in all situations, an autonomic approach that performs energy-efficient thermal management while ensuring the QoS delivered to the users is proposed. To address the problem of VM allocation that arises during VM migrations, an innovative application-centric energy-aware strategy for Virtual Machine (VM) allocation is proposed. The proposed strategy ensures high resource utilization and energy efficiency through VM consolidation while satisfying application QoS by exploiting knowledge obtained through application profiling along multiple dimensions (CPU, memory, and network bandwidth utilization). To support our arguments, we present the results obtained from an experimental evaluation on real hardware using HPC workloads under different scenarios. 相似文献
47.
Before describing the mainFet modelings today available, the main technological evolutions ofMesfet andTegfet are summarized. It is brought some information on the various physical effects that occur in the devices and that must be taken into account in the models. It is shown that the different kinds of modelings (Monte Carlo, two dimensional, one dimensional) constitute a continuous chain, where the different elements appear strictly complementary. Finally, the present situation concerning modeling ofMesfet andTegfet will be presented. 相似文献
48.
Marc C. Lobelle 《Software》1985,15(10):997-1010
This document evaluates the feasibility of diskless UNIX systems connected to a disk-providing machine via a local area network. The diskless UNIX systems are to be used as workstations in a UNIX United 1 UNIX is a trademark of A. T. & T. Bell Laboratories. environment. Several solutions are presented and estimated to enable booting, file system access and swapping. Implementation techniques, compatible with the UNIX United philosophy, are proposed. Specific topics covered are file servers, swap servers, disk servers, indirect drivers, system call service access from kernel coroutines of UNIX processes, and communication subsystems. It is shown that the modifications to the UNIX system can be limited to one new device driver in the diskless workstation and one in the system providing the secondary storage facility. 相似文献
49.
50.
Clarisse Roblin Steve Chiumento Cdric Jacqueline Eric Pinloche Cendrine Nicoletti Hamza Olleik Elise Courvoisier-Dezord Agns Amouric Christian Basset Louis Dru Marie Ollivier Aurlie Bogey-Lambert Nicolas Vidal Mohamed Atta Marc Maresca Estelle Devillard Victor Duarte Josette Perrier Mickael Lafond 《International journal of molecular sciences》2021,22(6)
The world is on the verge of a major antibiotic crisis as the emergence of resistant bacteria is increasing, and very few novel molecules have been discovered since the 1960s. In this context, scientists have been exploring alternatives to conventional antibiotics, such as ribosomally synthesized and post-translationally modified peptides (RiPPs). Interestingly, the highly potent in vitro antibacterial activity and safety of ruminococcin C1, a recently discovered RiPP belonging to the sactipeptide subclass, has been demonstrated. The present results show that ruminococcin C1 is efficient at curing infection and at protecting challenged mice from Clostridium perfringens with a lower dose than the conventional antibiotic vancomycin. Moreover, antimicrobial peptide (AMP) is also effective against this pathogen in the complex microbial community of the gut environment, with a selective impact on a few bacterial genera, while maintaining a global homeostasis of the microbiome. In addition, ruminococcin C1 exhibits other biological activities that could be beneficial for human health, as well as other fields of applications. Overall, this study, by using an in vivo infection approach, confirms the antimicrobial clinical potential and highlights the multiple functional properties of ruminococcin C1, thus extending its therapeutic interest. 相似文献