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131.
Cox-Foster DL Conlan S Holmes EC Palacios G Evans JD Moran NA Quan PL Briese T Hornig M Geiser DM Martinson V vanEngelsdorp D Kalkstein AL Drysdale A Hui J Zhai J Cui L Hutchison SK Simons JF Egholm M Pettis JS Lipkin WI 《Science (New York, N.Y.)》2007,318(5848):283-287
In colony collapse disorder (CCD), honey bee colonies inexplicably lose their workers. CCD has resulted in a loss of 50 to 90% of colonies in beekeeping operations across the United States. The observation that irradiated combs from affected colonies can be repopulated with naive bees suggests that infection may contribute to CCD. We used an unbiased metagenomic approach to survey microflora in CCD hives, normal hives, and imported royal jelly. Candidate pathogens were screened for significance of association with CCD by the examination of samples collected from several sites over a period of 3 years. One organism, Israeli acute paralysis virus of bees, was strongly correlated with CCD. 相似文献
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133.
In 2010, the Convention on Biological Diversity created the Aichi Biodiversity targets to aid the restoration of degraded ecosystems, which include the restoration of at least 15% of degraded ecosystems by 2020. A crucial step to achieve this goal is the development of nonbiased prioritization methodologies that help establish key areas for restoration. However, prioritization methodologies depend heavily on each country's economic capability, governance, internal politics, degradation level, and access to data. Because only 78 countries are considered high‐income economies, only this select group of countries would potentially have the necessary resources to compile the information needed to carry out a prioritization process. In this work, our aim was to analyze and compare key land degradation indicators (e.g., land use/change, primary productivity, biodiversity loss, soil organic carbon, degradation level, and social acceptance) in five world regions, with different incomes and political and cultural background, Africa, Asia, Europe, Latin America, North America (USA–Canada), and Oceania. We also grouped these key land degradation indicators by type (ecological, social, cultural, economic, and policy). Our results indicate that the different world regions seem not to have a direct impact on the number of land degradation indicators used. However, we found differences in the type of indicators used per region, partially denoting the idiosyncrasy of each of these regions. Our study shows that governance is important in the use of indicators although we suspect that there are other variables that could be at play not included in this study. 相似文献
134.
Diogo Corrêa Santos Pedro Walfir Martins Souza‐Filho Wilson da Rocha Nascimento Gustavo Freitas Cardoso Jorge Filipe dos Santos 《Land Degradation u0026amp; Development》2020,31(15):2033-2046
Railways are known to have less influence on land use than other transportation systems. However, railways also affect biodiversity, water resources, socioeconomic outcomes, and land prices. In the context of changes in land cover and land use (LCLU) classes, this study analyses the changes arising from the establishment of the Carajás Mining Project in 1984 along the more than 900‐km length of the Carajás Railway (CRW) in southeastern Amazonia. LANDSAT‐5 (1984) and LANDSAT‐8 (2014) satellite images and human settlement layers (1990 and 2015) along CRW were used to assess LCLU changes. Satellite images were analysed with the geographic object‐based image analysis method to detect changes in LCLU classes, including municipalities located less than 50 km from the CRW. The results showed that in 1984, the areas of influence of the CRW consisted of 69% forest cover, 24% nonforest cover, 3% water, and 2% cloud cover. In 2014, forest area dropped significantly to 43%, whereas the nonforest class expanded to 46%. This analysis revealed that the conversion of forests to pastures represents the major landscape degradation that occupy 51% of the study site mainly in rural human settlement areas, which are interlinked with the construction of the CRW. Only 6% of the total area exhibits a trend of restoration marked by secondary vegetation growing. The land occupation model along the CRW is characterized by rural settlements, associated with roads and extensive pasturelands. Construction of this railway in a certain way prevented the fishbone occupation type as observed in the western Amazon. 相似文献
135.
Pereira Gustavo Willam Valente Domingos Sárvio Magalhães de Queiroz Daniel Marçal Santos Nerilson Terra Fernandes-Filho Elpídio Inácio 《Precision Agriculture》2022,23(4):1189-1204
Precision Agriculture - Kriging has been shown to be the best interpolator to interpolate maps in precision agriculture. However, Kriging requires a high number of sampling points to generate... 相似文献
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Nomie De San Nicolas Aromal Asokan Rafael D. Rosa Sbastien N. Voisin Marie-Agns Travers Gustavo Rocha Luc Dantan Yann Dorant Guillaume Mitta Bruno Petton Guillaume M. Charrire Jean-Michel Escoubas Viviane Boulo Juliette Pouzadoux Herv Meudal Karine Loth Vincent Aucagne Agns F. Delmas Philippe Bulet Caroline Montagnani Delphine Destoumieux-Garzn 《Marine drugs》2022,20(12)
Big defensins are two-domain antimicrobial peptides (AMPs) that have highly diversified in mollusks. Cg-BigDefs are expressed by immune cells in the oyster Crassostrea gigas, and their expression is dampened during the Pacific Oyster Mortality Syndrome (POMS), which evolves toward fatal bacteremia. We evaluated whether Cg-BigDefs contribute to the control of oyster-associated microbial communities. Two Cg-BigDefs that are representative of molecular diversity within the peptide family, namely Cg-BigDef1 and Cg-BigDef5, were characterized by gene cloning and synthesized by solid-phase peptide synthesis and native chemical ligation. Synthetic peptides were tested for antibacterial activity against a collection of culturable bacteria belonging to the oyster microbiota, characterized by 16S sequencing and MALDI Biotyping. We first tested the potential of Cg-BigDefs to control the oyster microbiota by injecting synthetic Cg-BigDef1 into oyster tissues and analyzing microbiota dynamics over 24 h by 16S metabarcoding. Cg-BigDef1 induced a significant shift in oyster microbiota β-diversity after 6 h and 24 h, prompting us to investigate antimicrobial activities in vitro against members of the oyster microbiota. Both Cg-BigDef1 and Cg-BigDef5 were active at a high salt concentration (400 mM NaCl) and showed broad spectra of activity against bacteria associated with C. gigas pathologies. Antimicrobial specificity was observed for both molecules at an intra- and inter-genera level. Remarkably, antimicrobial spectra of Cg-BigDef1 and Cg-BigDef5 were complementary, and peptides acted synergistically. Overall, we found that primary sequence diversification of Cg-BigDefs has generated specificity and synergy and extended the spectrum of activity of this peptide family. 相似文献
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139.
Kawai Kentaro Fujita Hiroki Sanchez Gustavo Furusawa Shuichi Umino Tetsuya 《Fisheries Science》2020,86(4):645-653
Fisheries Science - We aimed to determine the spawning period of black sea bream Acanthopagrus schlegelii in Hiroshima Bay, Japan, based on the distribution of its eggs, to assist in the resource... 相似文献
140.
Rafael DeRossi Tiago J.C. MódoloRonaldo C. Pagliosa DVM Paulo H.A. JardimFelipe B. Maciel DVM Gustavo G. Macedo DVM MSc Dr 《Journal of Equine Veterinary Science》2012
The aim of this study was to compare the effects of caudal epidural bupivacaine alone (BP), bupivacaine plus morphine (BPMP), and bupivacaine plus ketamine (BPKE) for perineal analgesia in horses. Each of the six saddle horses received a caudal epidural catheter and underwent 3 treatments: BP, 0.25% (0.04 mg/kg) bupivacaine hydrochloride without epinephrine; BPMP, 0.02 mg/kg of bupivacaine combined with 0.1 mg/kg of morphine-preservative free; and BPKE, 0.02 mg/kg of bupivacaine combined with 0.5 mg/kg of ketamine. The order of treatments was randomized. The cardiovascular system, respiratory rate, quality of analgesia, sedation, and motor blockade were assessed before drug administration (baseline), at 5, 10, 15, and 30 minutes, and every 30 minutes thereafter until loss of analgesia. The median time to onset of analgesia was 5 minutes after BP treatment, faster than after BPKE or BPMP treatments, which were 10 minutes and 15 minutes, respectively (P < .05). The BPMP treatment produced analgesia (315 minutes) for a longer duration than BP treatment (210 minutes) or BPKE treatment (240 minutes), in the regions of the tail, perineum, and upper hind limb in horses. All treatments presented mild sedation or motor blockade. There were minimal effects on the cardiovascular system and respiratory rate. BPMP may be preferable to a high dose of BP or BPKE. Caudal epidural BPMP can be an appropriate choice for regional perineal analgesia in horses. 相似文献