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51.
Monitoring for management of conservation and recreation in Australian protected areas 总被引:2,自引:0,他引:2
Ralf Buckley Jessica Robinson Joanne Carmody Narelle King 《Biodiversity and Conservation》2008,17(14):3589-3606
Protected areas are key to conservation of biodiversity, and Australia is one of the world’s megadiverse regions. Monitoring
programs provide the information to assess the state of conservation resources, the severity of threats and the success of
management responses. Here we compare the management priorities, monitoring priorities and actual monitoring practices of
protected area management agencies in Australia, using four sets of data at continental scale and five at a more restricted
regional scale. We track changes over a period of several years and focus at successively finer levels of detail. At both
continental and regional scales, most management plans emphasise fire, invasive species and visitor management; and most monitoring
programmes refer to visitor numbers and impacts as well as species and ecosystems. There is only a weak match, however, between
reported management priorities and actual monitoring programmes; and the effectiveness of management responses is rarely monitored.
The level of detail in visitor monitor programmes varies considerably: most parks count visitors, but few know what those
visitors do. Threats from fire and invasive species receive more attention that those from recreation. At regional scale,
the proportion of parks with defined monitoring programmes and priorities increased significantly from 2003/2004 to 2006/2007.
Whilst only a proportion of protected areas monitor endangered species populations, for those that do this is the parameter
reported in most detail, with many parks reporting single records of single individuals. Some parks also maintain anecdotal
records of rare species outside routine monitoring programs. 相似文献
52.
Phenol-soluble modulin (PSM) is a peptide complex produced by the nosocomial pathogen Staphylococcus epidermidis that has a strong capacity to activate the human innate immune response. We developed a novel method based on liquid chromatography-mass spectrometry (LC-MS) to quantify the production of the individual PSM components. Each PSM peptide was abundant in most of the 76 S epidermidis strains tested. Importantly, none of the PSM components were secreted by an agr mutant strain, indicating that PSM synthesis is regulated strictly by the agr quorum-sensing system. Furthermore, the agr mutant strain failed to elicit production of TNFalpha by human myeloid cells and induced significantly less neutrophil chemotaxis compared with the wild-type strain. Thus, quorum-sensing in S. epidermidis dramatically influenced activation of human host defence. We propose that an agr quorum-sensing mechanism facilitates growth and survival in infected hosts by adapting production of the pro-inflammatory PSMs to the stage of infection. 相似文献
53.
54.
Boback SM Cox CL Ott BD Carmody R Wrangham RW Secor SM 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2007,148(3):651-656
The cooking of food is hypothesized to have played a major role in human evolution partly by providing an increase in net energy gain. For meat, cooking compromises the structural integrity of the tissue by gelatinizing the collagen. Hence, cooked meat should take less effort to digest compared to raw meat. Likewise, less energy would be expended digesting ground meat compared to intact meat. We tested these hypotheses by assessing how the cooking and/or grinding of meat influences the energy expended on its digestion, absorption, and assimilation (i.e., specific dynamic action, SDA) using the Burmese python, Python molurus. Pythons were fed one of four experimental diets each weighing 25% of the snake's body mass: intact raw beef, intact cooked beef, ground raw beef, and ground cooked beef. We measured oxygen consumption rates of snakes prior to and up to 14 days following feeding and calculated SDA from the extra oxygen consumed above standard metabolic rate. Postprandial peak in oxygen consumption, the scope of peak rates, and SDA varied significantly among meal treatments. Pythons digesting raw or intact meals exhibited significantly larger postprandial metabolic responses than snakes digesting the cooked ground meals. We found cooking to decrease SDA by 12.7%, grinding to decrease SDA by 12.4%, and the combination of the two (cooking and grinding) to have an additive effect, decreasing SDA by 23.4%. These results support the hypothesis that the consumption of cooked meat provides an energetic benefit over the consumption of raw meat. 相似文献
55.
Florian Ryffel Eric JN Helfrich Patrick Kiefer Lindsay Peyriga Jean-Charles Portais J?rn Piel Julia A Vorholt 《The ISME journal》2016,10(3):632-643
The phyllosphere, which is defined as the parts of terrestrial plants above the ground, is a large habitat for different microorganisms that show a high extent of adaption to their environment. A number of hypotheses were generated by culture-independent functional genomics studies to explain the competitiveness of specialized bacteria in the phyllosphere. In contrast, in situ data at the metabolome level as a function of bacterial colonization are lacking. Here, we aimed to obtain new insights into the metabolic interplay between host and epiphytes upon colonization of Arabidopsis thaliana leaves in a controlled laboratory setting using environmental metabolomics approaches. Quantitative nuclear magnetic resonance (NMR) and imaging high-resolution mass spectrometry (IMS) methods were used to identify Arabidopsis leaf surface compounds and their possible involvement in the epiphytic lifestyle by relative changes in compound pools. The dominant carbohydrates on the leaf surfaces were sucrose, fructose and glucose. These sugars were significantly and specifically altered after epiphytic leaf colonization by the organoheterotroph Sphingomonas melonis or the phytopathogen Pseudomonas syringae pv. tomato, but only to a minor extent by the methylotroph Methylobacterium extorquens. In addition to carbohydrates, IMS revealed surprising alterations in arginine metabolism and phytoalexin biosynthesis that were dependent on the presence of bacteria, which might reflect the consequences of bacterial activity and the recognition of not only pathogens but also commensals by the plant. These results highlight the power of environmental metabolomics to aid in elucidating the molecular basis underlying plant–epiphyte interactions in situ. 相似文献
56.
Barbara A. Bellaire John Carmody John Braud Dalton R. Gossett Stephen W. Banks M. Cranlucas 《Free radical research》2013,47(5):531-545
The role of abscisic acid (ABA) in the signal transduction pathway associated with NaCl-induced up-regulation of antioxidant enzyme activity was examined in a NaCl-tolerant cotton callus cell line treated with NaCl, ABA, paraquat, or H2O2 in the presence and absence or fluridone, an inhibitor of terpene, and therefore, ABA synthesis. Treatment with NaCl resulted in a rapid increase (within 30 minutes) in the ABA levels of the callus tissue, and the NaCl, ABA, and paraquat treatments induced rapid increases in the activities of superoxide dismutase, catalase, peroxidase, and glutathione reductase. Pre-treatment with fluridone significantly suppressed the NaCl-induced increases, but only slightly delayed the increases in tissue subjected to exogenous ABA treatment. This implies that ABA is involved in the signal transduction pathway associated with the NaCl-induced up-regulation of these antioxidant enzymes. Pre-treatment with fluridone had no effect on the paraquat-induced increases, suggesting that these enzymes can also be up-regulated by a pathway other than the one mediated by ABA. Both the NaCl and paraquat treatments produced significant increases in the superoxide levels within the callus, but the increase resulting from the paraquat treatment was significantly higher than the increase resulting from the NaCl treatment. These data suggest that NaCl stress results in the production of reactive oxygen intermediates (ROI) which signals the induction of an ABA-dependent signaling pathway. The production of very high levels of ROI, such as those that occur with paraquat treatment or perhaps during periods of prolonged or extreme stress, may induce an ABA-independent signaling pathway. 相似文献
57.
58.
Germain AR Carmody LC Dockendorff C Galan-Rodriguez C Rodriguez A Johnston S Bittker JA MacPherson L Dandapani S Palmer M Schreiber SL Munoz B 《Bioorganic & medicinal chemistry letters》2011,21(23):7197-7200
We report the outcome of a high-throughput small-molecule screen to identify novel, nontoxic, inhibitors of Trypansoma cruzi, as potential starting points for therapeutics to treat for both the acute and chronic stages of Chagas disease. Two compounds were identified that displayed nanomolar inhibition of T. cruzi and an absence of activity against host cells at the highest tested dose. These compounds have been registered with NIH Molecular Libraries Program (probes ML157 and ML158). 相似文献
59.
Henry W. Chase Jay C. Fournier Tsafrir Greenberg Jorge R. Almeida Richelle Stiffler Carlos R. Zevallos Haris Aslam Crystal Cooper Thilo Deckersbach Sarah Weyandt Phillip Adams Marisa Toups Tom Carmody Maria A. Oquendo Scott Peltier Maurizio Fava Patrick J. McGrath Myrna Weissman Ramin Parsey Melvin G. McInnis Benji Kurian Madhukar H. Trivedi Mary L. Phillips 《PloS one》2015,10(5)
Longitudinal investigation of the neural correlates of reward processing in depression may represent an important step in defining effective biomarkers for antidepressant treatment outcome prediction, but the reliability of reward-related activation is not well understood. Thirty-seven healthy control participants were scanned using fMRI while performing a reward-related guessing task on two occasions, approximately one week apart. Two main contrasts were examined: right ventral striatum (VS) activation fMRI BOLD signal related to signed prediction errors (PE) and reward expectancy (RE). We also examined bilateral visual cortex activation coupled to outcome anticipation. Significant VS PE-related activity was observed at the first testing session, but at the second testing session, VS PE-related activation was significantly reduced. Conversely, significant VS RE-related activity was observed at time 2 but not time 1. Increases in VS RE-related activity from time 1 to time 2 were significantly associated with decreases in VS PE-related activity from time 1 to time 2 across participants. Intraclass correlations (ICCs) in VS were very low. By contrast, visual cortex activation had much larger ICCs, particularly in individuals with high quality data. Dynamic changes in brain activation are widely predicted, and failure to account for these changes could lead to inaccurate evaluations of the reliability of functional MRI signals. Conventional measures of reliability cannot distinguish between changes specified by algorithmic models of neural function and noisy signal. Here, we provide evidence for the former possibility: reward-related VS activations follow the pattern predicted by temporal difference models of reward learning but have low ICCs. 相似文献
60.
Andrew R. Germain Leigh C. Carmody Partha P. Nag Barbara Morgan Lynn VerPlank Cristina Fernandez Etienne Donckele Yuxiong Feng Jose R. Perez Sivaraman Dandapani Michelle Palmer Eric S. Lander Piyush B. Gupta Stuart L. Schreiber Benito Munoz 《Bioorganic & medicinal chemistry letters》2013,23(6):1834-1838
A high-throughput screen (HTS) was conducted against stably propagated cancer stem cell (CSC)-enriched populations using a library of 300,718 compounds from the National Institutes of Health (NIH) Molecular Libraries Small Molecule Repository (MLSMR). A cinnamide analog displayed greater than 20-fold selective inhibition of the breast CSC-like cell line (HMLE_sh_Ecad) over the isogenic control cell line (HMLE_sh_eGFP). Herein, we report structure–activity relationships of this class of cinnamides for selective lethality towards CSC-enriched populations. 相似文献