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41.
Gabby N. Ahmadia Louise Glew Mikaela Provost David Gill Nur Ismu Hidayat Sangeeta Mangubhai Purwanto Helen E. Fox 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2015,370(1681)
Quasi-experimental impact evaluation approaches, which enable scholars to disentangle effects of conservation interventions from broader changes in the environment, are gaining momentum in the conservation sector. However, rigorous impact evaluation using statistical matching techniques to estimate the counterfactual have yet to be applied to marine protected areas (MPAs). While there are numerous studies investigating ‘impacts’ of MPAs that have generated considerable insights, results are variable. This variation has been linked to the biophysical and social context in which they are established, as well as attributes of management and governance. To inform decisions about MPA placement, design and implementation, we need to expand our understanding of conditions under which MPAs are likely to lead to positive outcomes by embracing advances in impact evaluation methodologies. Here, we describe the integration of impact evaluation within an MPA network monitoring programme in the Bird''s Head Seascape, Indonesia. Specifically we (i) highlight the challenges of implementation ‘on the ground’ and in marine ecosystems and (ii) describe the transformation of an existing monitoring programme into a design appropriate for impact evaluation. This study offers one potential model for mainstreaming impact evaluation in the conservation sector. 相似文献
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Nurlisa Yusuf Ammar Zakaria Mohammad Iqbal Omar Ali Yeon Md Shakaff Maz Jamilah Masnan Latifah Munirah Kamarudin Norasmadi Abdul Rahim Nur Zawatil Isqi Zakaria Azian Azamimi Abdullah Amizah Othman Mohd Sadek Yasin 《BMC bioinformatics》2015,16(1)
Background
Effective management of patients with diabetic foot infection is a crucial concern. A delay in prescribing appropriate antimicrobial agent can lead to amputation or life threatening complications. Thus, this electronic nose (e-nose) technique will provide a diagnostic tool that will allow for rapid and accurate identification of a pathogen.Results
This study investigates the performance of e-nose technique performing direct measurement of static headspace with algorithm and data interpretations which was validated by Headspace SPME-GC-MS, to determine the causative bacteria responsible for diabetic foot infection. The study was proposed to complement the wound swabbing method for bacterial culture and to serve as a rapid screening tool for bacteria species identification. The investigation focused on both single and poly microbial subjected to different agar media cultures. A multi-class technique was applied including statistical approaches such as Support Vector Machine (SVM), K Nearest Neighbor (KNN), Linear Discriminant Analysis (LDA) as well as neural networks called Probability Neural Network (PNN). Most of classifiers successfully identified poly and single microbial species with up to 90% accuracy.Conclusions
The results obtained from this study showed that the e-nose was able to identify and differentiate between poly and single microbial species comparable to the conventional clinical technique. It also indicates that even though poly and single bacterial species in different agar solution emit different headspace volatiles, they can still be discriminated and identified using multivariate techniques. 相似文献44.
New mechanisms and functions of actin nucleation 总被引:1,自引:0,他引:1
In cells the de novo nucleation of actin filaments from monomers requires actin-nucleating proteins. These fall into three main families--the Arp2/3 complex and its nucleation promoting factors (NPFs), formins, and tandem-monomer-binding nucleators. In this review, we highlight recent advances in understanding the molecular mechanism of actin nucleation by both well-characterized and newly identified nucleators, and explore current insights into their cellular functions in membrane trafficking, cell migration and division. The mechanisms and functions of actin nucleators are proving to be more complex than previously considered, with extensive cooperation and overlap in their cellular roles. 相似文献
45.
Nur Fariza Abd. RahmanMahiran Basri Mohd Basyaruddin Abdul RahmanRaja Noor Zaliha Raja Abdul Rahman Abu Bakar Salleh 《Bioresource technology》2011,102(3):2168-2176
Engkabang fat esters were produced via alcoholysis reaction between Engkabang fat and oleyl alcohol, catalyzed by Lipozyme RM IM. The reaction was carried out in a 500 ml Stirred tank reactor using heptane and hexane as solvents. Response surface methodology (RSM) based on a four-factor-five-level Central composite design (CCD) was applied to evaluate the effects of synthesis parameters, namely temperature, substrate molar ratio (oleyl alcohol: Engkabang fat), enzyme amount and impeller speed. The optimum yields of 96.2% and 91.4% were obtained for heptane and hexane at the optimum temperature of 53.9 °C, impeller speeds of 309.5 and 309.0 rpm, enzyme amounts of 4.82 and 5.65 g and substrate molar ratios of 2.94 and 3.39:1, respectively. The actual yields obtained compared well with the predicted values of 100.0% and 91.5%, respectively. Meanwhile, the properties of the esters show that they are suitable to be used as ingredient for cosmetic applications. 相似文献
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The leafy parts of thyme and its essential oil have been used in foods for its flavour, aroma and preservation for many years. In the present study the genotoxic potential of major compounds of thyme oil, i.e. thymol, carvacrol, and gamma-terpinene and of the methanolic extracts of thyme, were investigated in human lymphocytes by single-cell gel electrophoresis. Also, the effects of these substances on the induction of DNA damage by 2-amino-3-methylimidazo[4,5-f]-quinoline (IQ) and mitomycin C (MMC) were evaluated. No increase in DNA strand breakage was observed at thymol and gamma-terpinene concentrations below 0.1 mM, but at the higher concentration of 0.2 mM significant increases in DNA damage were seen. Thymol and gamma-terpinene significantly reduced the DNA strand breakage induced by IQ and MMC at the lower concentrations studied. Carvacrol, which is an isomer of thymol, seemed to protect lymphocytes from the genotoxic effects of IQ and MMC at non-toxic concentrations below 0.05 mM, but at the higher concentration of 0.1 mM carvacrol itself induced DNA damage. Also the constituents of the n-hexane and ethyl acetate fractions prepared from the concentrated aqueous methanolic extracts of Thymus spicata protected lymphocytes against IQ- and MMC-induced DNA damage in a concentration-dependent manner. 相似文献
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Dispersal-assembly theories of species coexistence posit that environmental factors play no role in explaining community diversity and structure. Dispersal-assembly theories shed light on some aspects of community structure such as species-area and species-abundance relationships. However, species environmental associations also affect these measures of community structure. Measurements of species niche breadth and overlap address this influence. Using a new continuous measure of niche and a dispersal-assembly null model that maintains species niche breadth and aggregation, we tested two hypotheses assessing the effects of habitat heterogeneity on the ability of dispersal-assembly theories to explain community niche structure. We found that in both homogenous and heterogeneous environments dispersal-assembly theories cannot fully explain observed niche structure. The performance of the dispersal-assembly null models was particularly poor in heterogeneous environments. These results indicate that non-dispersal based mechanisms are in part responsible for observed community structure and measures of community structure which include species environmental associations should be used to test theories of species diversity. 相似文献
50.
Raja Nur Ateeka Othman Gregory J. Jordan James R. P. Worth Dorothy A. Steane Marco F. Duretto 《Plant Systematics and Evolution》2010,288(3-4):127-138
This paper presents phylogenies of the small but ecologically and horticulturally important Australian genus Correa (Rutaceae). Consensus phylogenies generated using parsimony were congruent with their counterparts generated by Bayesian analysis, although usually less well resolved. The phylogeny generated from the second internal transcribed spacer region of the nuclear ribosomal DNA supported the monophyly of Correa and identified two well supported clades (one comprising C. lawrenceana and C. baeuerlenii and the other containing all other species of the genus). Phylogenetic reconstructions based on the combined trnL-trnF spacer and the trnK intron (including the matK gene) regions of chloroplast DNA also supported the monophyly of Correa and of the C. lawrenceana/C. baeuerlenii clade, but the topology among the other species differed markedly from that in the ITS-based phylogeny. The major clades identified in the chloroplast phylogenies seemed to follow geographic patterns rather than species boundaries, with different samples of C. glabra bearing chloroplast genotypes from different clades. These patterns are likely to be because of independent evolution of the chloroplast and nuclear genomes, and are typical of cases of introgressive hybridisation among species or incomplete lineage sorting of chloroplast genomes leading to incongruence between chloroplast and nuclear phylogenies. Thus, the phylogenies based on nuclear DNA should reflect species relations better than the chloroplast phylogeny in Correa, and we propose a new subgeneric classification of the genus on the basis of the ITS-based phylogeny and morphology. Correa subgenus Persistens Othman, Duretto and G.J. Jord., containing C. lawrenceana and C. baeuerlenii, is formally described. 相似文献