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111.
The performance and scalability of communications are key for high performance computing (HPC) applications in the current multi-core era. Despite the significant benefits (e.g., productivity, portability, multithreading) of Java for parallel programming, its poor communications support has hindered its adoption in the HPC community. This paper presents FastMPJ, an efficient message-passing in Java (MPJ) library, boosting Java for HPC by: (1) providing high-performance shared memory communications using Java threads; (2) taking full advantage of high-speed cluster networks (e.g., InfiniBand) to provide low-latency and high bandwidth communications; (3) including a scalable collective library with topology aware primitives, automatically selected at runtime; (4) avoiding Java data buffering overheads through zero-copy protocols; and (5) implementing the most widely extended MPI-like Java bindings for a highly productive development. The comprehensive performance evaluation on representative testbeds (InfiniBand, 10 Gigabit Ethernet, Myrinet, and shared memory systems) has shown that FastMPJ communication primitives rival native MPI implementations, significantly improving the efficiency and scalability of Java HPC parallel applications.  相似文献   
112.
jModelTest 2: more models, new heuristics and parallel computing   总被引:13,自引:0,他引:13  
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113.

Aim

The abyssal Clarion-Clipperton Zone (CCZ), Pacific Ocean, is an area of commercial importance owing to the growing interest in mining high-grade polymetallic nodules at the seafloor for battery metals. Research into the spatial patterns of faunal diversity, composition, and population connectivity is needed to better understand the ecological impacts of potential resource extraction. Here, a DNA taxonomy approach is used to investigate regional-scale patterns of taxonomic and phylogenetic alpha and beta diversity, and genetic connectivity, of the dominant macrofaunal group (annelids) across a 6 million km2 region of the abyssal seafloor.

Location

The abyssal seafloor (3932–5055 m depth) of the Clarion-Clipperton Zone, equatorial Pacific Ocean.

Methods

We used a combination of new and published barcode data to study 1866 polychaete specimens using molecular species delimitation. Both phylogenetic and taxonomic alpha and beta diversity metrics were used to analyse spatial patterns of biodiversity. Connectivity analyses were based on haplotype distributions for a subset of the studied taxa.

Results

DNA taxonomy identified 291–314 polychaete species from the COI and 16S datasets respectively. Taxonomic and phylogenetic beta diversity between sites were relatively high and mostly explained by lineage turnover. Over half of pairwise comparisons were more phylogenetically distinct than expected based on their taxonomic diversity. Connectivity analyses in abundant, broadly distributed taxa suggest an absence of genetic structuring driven by geographical location.

Main Conclusions

Species diversity in abyssal Pacific polychaetes is high relative to other deep-sea regions. Results suggest that environmental filtering, where the environment selects against certain species, may play a significant role in regulating spatial patterns of biodiversity in the CCZ. A core group of widespread species have diverse haplotypes but are well connected over broad distances. Our data suggest that the high environmental and faunal heterogeneity of the CCZ should be considered in future policy decisions.  相似文献   
114.
The effects of arsanilic acid as promoter of faster growth on the nutrition index and intestinal absorption of galactose and arabinose has been studied in growing rats. The rats that received arsanilic acid 0.7 mg/day added to water showed gain in body weight and feed intake, I.T. (feed conversion ratio) decrease and P.E.R. (protein efficiency ratio) increase. A dose of 1.4 mg/day produced harmful effects. The in vitro intestinal transport of galactose and arabinose decreased and increased respectively in animals that received additive in comparison with controls.  相似文献   
115.

Background  

Zibotentan (ZD4054) is a specific endothelin A (ETA) receptor antagonist being investigated for the treatment of prostate cancer. As zibotentan is eliminated by renal and metabolic routes, clearance may be reduced in patients with hepatic or renal impairment, leading to greater drug exposure.  相似文献   
116.
The various land management and planning policies that have been developed for the Tierra de Campos district of northwestern Spain over the past century have had major effects on wetland ecosystems of this area. To assist conservation planners in the future management of these habitats, this study outlines the changes that have occurred in these environments using data for the years 1900, 1956, 1984 and 2007. Multiple logistic regression models allowed the accurate projection of locations of wetlands that need to be restored or regenerated. These models were developed using a combination of 19 explanatory variables including: data related to historic lakelets, variations in the surfaces of wetlands, soil physicochemical and weather data, and socioeconomic and spatial planning data, as depicted by thematic mapping. The landscape used for projecting the wetlands in the study area was classified into five categories based on the probability of the presence of lakelets: very low, low, medium, high and very high. These generated maps show that the spatial extent of the wetlands of the Tierra de Campos district was 2.78 % in 1900–1933 and decreased to 0.65 % in 2007–2008. Accordingly, a dramatic decrease in the spatial extent covered by these ecosystems is observed over the twentieth century according to these maps; consequently these results highlight the effects of positive (protective) or negative (desiccative) policies implemented in the area.  相似文献   
117.
Giovanni Forzieri  Loïc P. Dutrieux  Agata Elia  Bernd Eckhardt  Giovanni Caudullo  Flor Álvarez Taboada  Alessandro Andriolo  Flavius Bălăcenoiu  Ana Bastos  Andrei Buzatu  Fernando Castedo Dorado  Lumír Dobrovolný  Mihai-Leonard Duduman  Angel Fernandez-Carrillo  Rocío Hernández-Clemente  Alberto Hornero  Săvulescu Ionuț  María J. Lombardero  Samuli Junttila  Petr Lukeš  Leonardo Marianelli  Hugo Mas  Marek Mlčoušek  Francesco Mugnai  Constantin Nețoiu  Christo Nikolov  Nicolai Olenici  Per-Ola Olsson  Francesco Paoli  Marius Paraschiv  Zdeněk Patočka  Eduardo Pérez-Laorga  Jose Luis Quero  Marius Rüetschi  Sophie Stroheker  Davide Nardi  Ján Ferenčík  Andrea Battisti  Henrik Hartmann  Constantin Nistor  Alessandro Cescatti  Pieter S. A. Beck 《Global Change Biology》2023,29(21):6040-6065
Insect and disease outbreaks in forests are biotic disturbances that can profoundly alter ecosystem dynamics. In many parts of the world, these disturbance regimes are intensifying as the climate changes and shifts the distribution of species and biomes. As a result, key forest ecosystem services, such as carbon sequestration, regulation of water flows, wood production, protection of soils, and the conservation of biodiversity, could be increasingly compromised. Despite the relevance of these detrimental effects, there are currently no spatially detailed databases that record insect and disease disturbances on forests at the pan-European scale. Here, we present the new Database of European Forest Insect and Disease Disturbances (DEFID2). It comprises over 650,000 harmonized georeferenced records, mapped as polygons or points, of insects and disease disturbances that occurred between 1963 and 2021 in European forests. The records currently span eight different countries and were acquired through diverse methods (e.g., ground surveys, remote sensing techniques). The records in DEFID2 are described by a set of qualitative attributes, including severity and patterns of damage symptoms, agents, host tree species, climate-driven trigger factors, silvicultural practices, and eventual sanitary interventions. They are further complemented with a satellite-based quantitative characterization of the affected forest areas based on Landsat Normalized Burn Ratio time series, and damage metrics derived from them using the LandTrendr spectral–temporal segmentation algorithm (including onset, duration, magnitude, and rate of the disturbance), and possible interactions with windthrow and wildfire events. The DEFID2 database is a novel resource for many large-scale applications dealing with biotic disturbances. It offers a unique contribution to design networks of experiments, improve our understanding of ecological processes underlying biotic forest disturbances, monitor their dynamics, and enhance their representation in land-climate models. Further data sharing is encouraged to extend and improve the DEFID2 database continuously. The database is freely available at https://jeodpp.jrc.ec.europa.eu/ftp/jrc-opendata/FOREST/DISTURBANCES/DEFID2/ .  相似文献   
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The link between various pathologies and atmospheric conditions has been a constant topic of study over recent decades in many places across the world; knowing more about it enables us to pre-empt the worsening of certain diseases, thereby optimizing medical resources. This study looked specifically at the connections in winter between respiratory diseases and types of atmospheric weather conditions (Circulation Weather Types, CWT) in Galicia, a region in the north-western corner of the Iberian Peninsula. To do this, the study used hospital admission data associated with these pathologies as well as an automatic classification of weather types. The main result obtained was that weather types giving rise to an increase in admissions due to these diseases are those associated with cold, dry weather, such as those in the east and south-east, or anticyclonic types. A second peak was associated with humid, hotter weather, generally linked to south-west weather types. In the future, this result may help to forecast the increase in respiratory pathologies in the region some days in advance.  相似文献   
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