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排序方式: 共有807条查询结果,搜索用时 15 毫秒
51.
Jena R. Hickey Janet Nackoney Nathan P. Nibbelink Stephen Blake Aime Bonyenge Sally Coxe Jef Dupain Maurice Emetshu Takeshi Furuichi Falk Grossmann Patrick Guislain John Hart Chie Hashimoto Bernard Ikembelo Omari Ilambu Bila-Isia Inogwabini Innocent Liengola Albert Lotana Lokasola Alain Lushimba Fiona Maisels Joel Masselink Valentin Mbenzo Norbert Mbangia Mulavwa Pascal Naky Nicolas Mwanza Ndunda Pele Nkumu Valentin Omasombo Gay Edwards Reinartz Robert Rose Tetsuya Sakamaki Samantha Strindberg Hiroyuki Takemoto Ashley Vosper Hjalmar S. Kühl 《Biodiversity and Conservation》2013,22(13-14):3085-3104
Habitat loss and hunting threaten bonobos (Pan paniscus), Endangered (IUCN) great apes endemic to lowland rainforests of the Democratic Republic of Congo. Conservation planning requires a current, data-driven, rangewide map of probable bonobo distribution and an understanding of key attributes of areas used by bonobos. We present a rangewide suitability model for bonobos based on a maximum entropy algorithm in which data associated with locations of bonobo nests helped predict suitable conditions across the species’ entire range. We systematically evaluated available biotic and abiotic factors, including a bonobo-specific forest fragmentation layer (forest edge density), and produced a final model revealing the importance of simple threat-based factors in a data poor environment. We confronted the issue of survey bias in presence-only models and devised a novel evaluation approach applicable to other taxa by comparing models built with data from geographically distinct sub-regions that had higher survey effort. The model’s classification accuracy was high (AUC = 0.82). Distance from agriculture and forest edge density best predicted bonobo occurrence with bonobo nests more likely to occur farther from agriculture and in areas of lower edge density. These results suggest that bonobos either avoid areas of higher human activity, fragmented forests, or both, and that humans reduce the effective habitat of bonobos. The model results contribute to an increased understanding of threats to bonobo populations, as well as help identify priority areas for future surveys and determine core bonobo protection areas. 相似文献
52.
Objective
To evaluate whether multisystemic therapy (MST) is more cost-effective than statutory interventions that are currently available for young offenders in England.Method
A cost-offset evaluation of MST based on data from a randomised controlled trial conducted in North London, England, comparing MST with usual services provided by two youth offending teams (YOT). Service costs were compared to cost savings in terms of rates of criminal re-offending.Results
108 adolescents, aged 11–17 years, were randomly allocated to MST+YOT (n = 56) or YOT alone (n = 52). Reductions in offending were evident in both groups, but were higher in the MST+YOT group. At 18-month follow-up, the MST+YOT group cost less in terms of criminal activity (£9,425 versus £11,715, p = 0.456). The MST+YOT group were significantly cheaper in terms of YOT services than the YOT group (£3,402 versus £4,619, p = 0.006), but more expensive including the cost of MST, although not significantly so (£5,687 versus £4,619, p = 0.195). The net benefit per young person for the 18-month follow-up was estimated to be £1,222 (95% CI −£5,838 to £8,283).Conclusions
The results reported in this study support the finding that MST+YOT has scope for cost-savings when compared to YOT alone. However, the limitations of the study in terms of method of economic evaluation, outcome measures used and data quality support the need for further research. 相似文献53.
Mauricio Rangel-Gomez Clayton Hickey Therese van Amelsvoort Pierre Bet Martijn Meeter 《PloS one》2013,8(6)
Despite much research, it remains unclear if dopamine is directly involved in novelty detection or plays a role in orchestrating the subsequent cognitive response. This ambiguity stems in part from a reliance on experimental designs where novelty is manipulated and dopaminergic activity is subsequently observed. Here we adopt the alternative approach: we manipulate dopamine activity using apomorphine (D1/D2 agonist) and measure the change in neurological indices of novelty processing. In separate drug and placebo sessions, participants completed a von Restorff task. Apomorphine speeded and potentiated the novelty-elicited N2, an Event-Related Potential (ERP) component thought to index early aspects of novelty detection, and caused novel-font words to be better recalled. Apomorphine also decreased the amplitude of the novelty-P3a. An increase in D1/D2 receptor activation thus appears to potentiate neural sensitivity to novel stimuli, causing this content to be better encoded. 相似文献
54.
55.
Phillip J. Dugger Pedro G. Blendinger Katrin Bhning‐Gaese Lackson Chama Marta Correia D. Matthias Dehling Carine Emer Nina Farwig Evan C. Fricke Mauro Galetti Daniel García Ingo Grass Ruben Heleno Fbio A. F. Jacomassa Suelen Moraes Catherine Moran Marcia C. Muoz Eike Lena Neuschulz Larissa Nowak Augusto Piratelli Marco A. Pizo Marta Quitin Haldre S. Rogers Romn A. Ruggera Francisco Saavedra Mariano S. Snchez Rocío Snchez Vinicio Santilln Dana G. Schabo Fernanda Ribeiro da Silva Srgio Timteo Anna Traveset Maximilian G. R. Vollstdt Matthias Schleuning 《Global Ecology and Biogeography》2019,28(2):248-261
56.
Joan Rhl Zoe E. West Maren Rudolph Andreea Zaharia Derek Van Lonkhuyzen Danica K. Hickey Annalese B. T. Semmler Rachael Z. Murray 《Traffic (Copenhagen, Denmark)》2019,20(9):661-673
Macrophage migration into injured or infected tissue is a key aspect in the pathophysiology of many diseases where inflammation is a driving factor. Membrane‐type‐1 matrix metalloproteinase (MT1‐MMP) cleaves extracellular matrix components to facilitate invasion. Here we show that, unlike the constitutive MT1‐MMP surface recycling seen in cancer cells, unactivated macrophages express low levels of MT1‐MMP. Upon lipopolysaccharide (LPS) activation, MT1‐MMP synthesis dramatically increases 10‐fold at the surface by 15 hours. MT1‐MMP is trafficked from the Golgi complex to the surface via late endosomes/lysosomes in a pathway regulated by the late endosome/lysosome R‐SNAREs VAMP7 and VAMP8. These form two separate complexes with the surface Q‐SNARE complex Stx4/SNAP23 to regulate MT1‐MMP delivery to the plasma membrane. Loss of either one of these SNAREs leads to a reduction in surface MT1‐MMP, gelatinase activity and reduced invasion. Thus, inhibiting MT1‐MMP transport through this pathway could reduce macrophage migration and the resulting inflammation. 相似文献
57.
It is now well-established that compositional bias in DNA sequences can adversely affect phylogenetic analysis based on those
sequences. Phylogenetic analyses based on protein sequences are generally considered to be more reliable than those derived
from the corresponding DNA sequences because it is believed that the use of encoded protein sequences circumvents the problems
caused by nucleotide compositional biases in the DNA sequences. There exists, however, a correlation between AT/GC bias at
the nucleotide level and content of AT- and GC-rich codons and their corresponding amino acids. Consequently, protein sequences
can also be affected secondarily by nucleotide compositional bias. Here, we report that DNA bias not only may affect phylogenetic
analysis based on DNA sequences, but also drives a protein bias which may affect analyses based on protein sequences. We present
a striking example where common phylogenetic tools fail to recover the correct tree from complete animal mitochondrial protein-coding
sequences. The data set is very extensive, containing several thousand sites per sequence, and the incorrect phylogenetic
trees are statistically very well supported. Additionally, neither the use of the LogDet/paralinear transform nor removal
of positions in the protein alignment with AT- or GC-rich codons allowed recovery of the correct tree. Two taxa with a large
compositional bias continually group together in these analyses, despite a lack of close biological relatedness. We conclude
that even protein-based phylogenetic trees may be misleading, and we advise caution in phylogenetic reconstruction using protein
sequences, especially those that are compositionally biased.
Received: 19 February 1998 / Accepted: 28 August 1998 相似文献
58.
59.
Monteiro-Vitorello CB Camargo LE Van Sluys MA Kitajima JP Truffi D do Amaral AM Harakava R de Oliveira JC Wood D de Oliveira MC Miyaki C Takita MA da Silva AC Furlan LR Carraro DM Camarotte G Almeida NF Carrer H Coutinho LL El-Dorry HA Ferro MI Gagliardi PR Giglioti E Goldman MH Goldman GH Kimura ET Ferro ES Kuramae EE Lemos EG Lemos MV Mauro SM Machado MA Marino CL Menck CF Nunes LR Oliveira RC Pereira GG Siqueira W de Souza AA Tsai SM Zanca AS Simpson AJ Brumbley SM Setúbal JC 《Molecular plant-microbe interactions : MPMI》2004,17(8):827-836
The genome sequence of Leifsonia xyli subsp. xyli, which causes ratoon stunting disease and affects sugarcane worldwide, was determined. The single circular chromosome of Leifsonia xyli subsp. xyli CTCB07 was 2.6 Mb in length with a GC content of 68% and 2,044 predicted open reading frames. The analysis also revealed 307 predicted pseudogenes, which is more than any bacterial plant pathogen sequenced to date. Many of these pseudogenes, if functional, would likely be involved in the degradation of plant heteropolysaccharides, uptake of free sugars, and synthesis of amino acids. Although L. xyli subsp. xyli has only been identified colonizing the xylem vessels of sugarcane, the numbers of predicted regulatory genes and sugar transporters are similar to those in free-living organisms. Some of the predicted pathogenicity genes appear to have been acquired by lateral transfer and include genes for cellulase, pectinase, wilt-inducing protein, lysozyme, and desaturase. The presence of the latter may contribute to stunting, since it is likely involved in the synthesis of abscisic acid, a hormone that arrests growth. Our findings are consistent with the nutritionally fastidious behavior exhibited by L. xyli subsp. xyli and suggest an ongoing adaptation to the restricted ecological niche it inhabits. 相似文献
60.
Exploiting the potential of insects for in vivo pathogenicity testing of microbial pathogens 总被引:5,自引:0,他引:5
Conventional assays for quantifying the virulence of microbial pathogens and mutants have traditionally relied upon the use of a range of mammalian species. A number of workers have demonstrated that insects can be used for evaluating microbial pathogenicity and provide results comparable to those that can be obtained with mammals since one component of the vertebrate immune system, the innate immune response, remains similar to that found in insects. Larvae of the Greater Wax Moth Galleria mellonella have been used to evaluate the virulence of a range of bacterial and fungal pathogens and a correlation with the virulence of these microbes in mice has been established. This review highlights the similarities of the vertebrate and insect innate immune responses to infection and identifies the potential use of insects for the in vivo evaluation of the microbial pathogenicity. 相似文献