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41.
Bats account for 30% of mammal diversity in SE Asia and are potential bioindicators of wider biodiversity impacts resulting from habitat loss and climate change.As existing sampling techniques in the region typically fail to record bats that habitually fly in open areas and at higher altitudes,current inventory efforts are less than comprehensive.Acoustic sampling with bat detectors may help to overcome these limitations for insectivorous bats,but has yet to be tested in mainland SE Asia.To do so,we sampled... 相似文献
42.
IB Masters MM Eastburn PW Francis R Wootton PV Zimmerman RS Ware AB Chang 《Respiratory research》2005,6(1):16
Background
Flexible video bronchoscopes, in particular the Olympus BF Type 3C160, are commonly used in pediatric respiratory medicine. There is no data on the magnification and distortion effects of these bronchoscopes yet important clinical decisions are made from the images. The aim of this study was to systematically describe the magnification and distortion of flexible bronchoscope images taken at various distances from the object.Methods
Using images of known objects and processing these by digital video and computer programs both magnification and distortion scales were derived.Results
Magnification changes as a linear function between 100 mm (×1) and 10 mm (×9.55) and then as an exponential function between 10 mm and 3 mm (×40) from the object. Magnification depends on the axis of orientation of the object to the optic axis or geometrical axis of the bronchoscope. Magnification also varies across the field of view with the central magnification being 39% greater than at the periphery of the field of view at 15 mm from the object. However, in the paediatric situation the diameter of the orifices is usually less than 10 mm and thus this limits the exposure to these peripheral limits of magnification reduction. Intraclass correlations for measurements and repeatability studies between instruments are very high, r = 0.96. Distortion occurs as both barrel and geometric types but both types are heterogeneous across the field of view. Distortion of geometric type ranges up to 30% at 3 mm from the object but may be as low as 5% depending on the position of the object in relation to the optic axis.Conclusion
We conclude that the optimal working distance range is between 40 and 10 mm from the object. However the clinician should be cognisant of both variations in magnification and distortion in clinical judgements. 相似文献43.
Biodiversity investment priorities are a major concern for funding agencies and parties to the Convention on Biodiversity.
We present a cost-effectiveness index designed to rank global biodiversity investments addressing weaknesses identified in
several existing procedures. First, we explicitly address the issue of cost. Biodiversity conservation can be expensive --
ensuring that money is efficiently spent is important if conserving maximum biodiversity is an objective. Second, a high degree
of threat to biodiversity is commonly accepted as constituting the principal reason for intervention and a basis for prioritization.
The possibility that a high degree of threat might constitute a reason for non-intervention is rarely considered. The index
presented in this study seeks to address these shortcomings by incorporating biodiversity ‘cost’, as measured by investment,
and biodiversity ‘benefit’, as measured by a representative biodiversity indicator, species, richness. These elements form
the basis of the cost -- benefit ratio needed for cost-effectiveness analysis. Investment in biodiversity is affected by issues
of vulnerability (threat) and viability (success). A successful investment intervention will, however, depend on the probability
or likelihood of success and the degree of threat prevalent in a particular country. These are integrated into the index as
probabilities which will influence the amount of biodiversity ‘saved’ by an intervention. We apply the index using data for
the Asia – Pacific region, to provide a cost-effective priority investment index (CEPII) ranking by country. Acute data limitations
at the global level particularly in applying complementarity, necessitate caution in the interpretation of the index which,
like other methods, requires some subjective choice of success and threat surrogates. The index continues the task of combining
scientific and socioeconomic criteria relevant to global priorities.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
44.
45.
Single cell profiling was performed to assess differences in RNA accumulation in neighboring hyphae of the fungus Aspergillus niger. A protocol was developed to isolate and amplify RNA from single hyphae or parts thereof. Microarray analysis resulted in
a present call for 4 to 7% of the A. niger genes, of which 12% showed heterogeneous RNA levels. These genes belonged to a wide range of gene categories. 相似文献
46.
Edith HC Cup Astrid Kinébanian Ton Satink Allan J Pieterse Henk T Hendricks Rob AB Oostendorp Gert Jan van der Wilt Baziel GM van Engelen 《BMC neurology》2011,11(1):86
Background
Myotonic dystrophy type 1 (MD1) is one of the most prevalent neuromuscular diseases, yet very little is known about how MD1 affects the lives of couples and how they themselves manage individually and together. To better match health care to their problems, concerns and needs, it is important to understand their perspective of living with this hereditary, systemic disease. 相似文献47.
Mi-Sun Kim Jichan Jang Nurlilah Binte AB Rahman Kevin Pethe Edward A. Berry Li-Shar Huang 《The Journal of biological chemistry》2015,290(23):14350-14360
Recently, energy production pathways have been shown to be viable antitubercular drug targets to combat multidrug-resistant tuberculosis and eliminate pathogen in the dormant state. One family of drugs currently under development, the imidazo[1,2-a]pyridine derivatives, is believed to target the pathogen''s homolog of the mitochondrial bc1 complex. This complex, denoted cytochrome bcc, is highly divergent from mitochondrial Complex III both in subunit structure and inhibitor sensitivity, making it a good target for drug development. There is no soluble cytochrome c in mycobacteria to transport electrons from the bcc complex to cytochrome oxidase. Instead, the bcc complex exists in a “supercomplex” with a cytochrome aa3-type cytochrome oxidase, presumably allowing direct electron transfer. We describe here purification and initial characterization of the mycobacterial cytochrome bcc-aa3 supercomplex using a strain of M. smegmatis that has been engineered to express the M. tuberculosis cytochrome bcc. The resulting hybrid supercomplex is stable during extraction and purification in the presence of dodecyl maltoside detergent. It is hoped that this purification procedure will potentiate functional studies of the complex as well as crystallographic studies of drug binding and provide structural insight into a third class of the bc complex superfamily. 相似文献
48.
Claire J Greenhill Gareth W Jones Mari A Nowell Zarabeth Newton Ann K Harvey Abdul N Moideen Fraser L Collins Anja C Bloom Rebecca C Coll Avril AB Robertson Matthew A Cooper Marcela Rosas Philip R Taylor Luke A O’Neill Ian R Humphreys Anwen S Williams Simon A Jones 《Arthritis research & therapy》2014,16(4)
Introduction
Activation of the inflammasome has been implicated in the pathology of various autoinflammatory and autoimmune diseases. While the NLRP3 inflammasome has been linked to arthritis progression, little is known about its synovial regulation or contribution to joint histopathology. Regulators of inflammation activation, such as interleukin (IL)-10, may have the potential to limit the inflammasome-driven arthritic disease course and associated structural damage. Hence, we used IL-10-deficient (IL-10KO) mice to assess NLRP3 inflammasome-driven arthritic pathology.Methods
Antigen-induced arthritis (AIA) was established in IL-10KO mice and wild-type controls. Using histological and radiographic approaches together with quantitative real-time PCR of synovial mRNA studies, we explored the regulation of inflammasome components. These were combined with selective blocking agents and ex vivo investigative studies in osteoclast differentiation assays.Results
In AIA, IL-10KO mice display severe disease with increased histological and radiographic joint scores. Here, focal bone erosions were associated with increased tartrate-resistant acid phosphatase (TRAP)-positive cells and a localized expression of IL-1β. When compared to controls, IL-10KO synovium showed increased expression of Il1b, Il33 and NLRP3 inflammasome components. Synovial Nlrp3 and Casp1 expression further correlated with Acp5 (encoding TRAP), while neutralization of IL-10 receptor signaling in control mice caused increased expression of Nlrp3 and Casp1. In ex vivo osteoclast differentiation assays, addition of exogenous IL-10 or selective blockade of the NLRP3 inflammasome inhibited osteoclastogenesis.Conclusions
These data provide a link between IL-10, synovial regulation of the NLRP3 inflammasome and the degree of bone erosions observed in inflammatory arthritis.Electronic supplementary material
The online version of this article (doi:10.1186/s13075-014-0419-y) contains supplementary material, which is available to authorized users. 相似文献49.
50.
Lonneke Smeding Frans B Pl?tz Regis R Lamberts Willem J van der Laarse Martin CJ Kneyber AB Johan Groeneveld 《Respiratory research》2012,13(1):23