The oligotrophic freshwater bacterium Caulobacter crescentus encodes a cluster of genes (CC_1487 to CC_1495) shown here to be necessary for metabolism of D-galacturonate, the primary constituent of pectin, a major pla...
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The oligotrophic freshwater bacterium Caulobacter crescentus encodes a cluster of genes (CC_1487 to CC_1495) shown here to be necessary for metabolism of D-galacturonate, the primary constituent of pectin, a major plant polymer. Sequence analysis suggests that these genes encode a version of the bacterial hexuronate isomerase pathway. A conserved 14 bp sequence motif is associated with promoter regions of three operons within this cluster, and is conserved in homologous gene clusters in related alpha-Proteobacteria. Embedded in the hexuronate gene cluster is a gene (CC_1489) encoding a member of the LacI family of bacterial transcription factors. This gene product, designated here as HumR (hexuronate metabolism regulator), represses expression of the uxaA and uxaC operon promoters by binding to the conserved operator sequence. Repression is relieved in the presence of galacturonate or, to a lesser extent, by glucuronate. Other genes potentially involved in pectin degradation and hexuronate transport are also under the control of HumR. Adoption of a LacI-type repressor to control hexuronate metabolism parallels the regulation of xylose, glucose, and maltose utilization in C. crescentus, but is distinct from the use of GntR-type repressors to control pectin and hexuronate utilization in gamma-Proteobacteria such as Escherichia coli.
BACKGROUND: Healthcare professionals have a duty to maintain basic life support(BLS) skills. This study aims to evaluate medical students' factual knowledge of BLS and the training they ***: A cross-sectional, closed-...
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BACKGROUND: Healthcare professionals have a duty to maintain basic life support(BLS) skills. This study aims to evaluate medical students' factual knowledge of BLS and the training they ***: A cross-sectional, closed-response questionnaire was distributed to the fi rst-and fourth-year students studying at institutions in the United Kingdom. The paper questionnaire sought to quantify respondent's previous BLS training, factual knowledge of the BLS algorithm using five multiple choice questions(MCQs), and valuate their desire for further BLS training. Students received 1 point for each correctly identifi ed answer to the 5 MCQ'***: A total of 3,732 complete responses were received from 21 medical schools. Eighty percent(n=2,999) of students completed a BLS course as part of their undergraduate medical studies. There was a signifi cant difference(P<0.001) in the percentage of the fourth-year students selecting the correct answer in all the MCQ's compared to the fi rst-year students except in identifyingthe correct depth of compressions required during CPR(P=0.095). Overall 10.3%(95% CI 9.9% to 10.7%) of respondents correctly identified the answer to 5 MCQ's on BLS: 9% of the first-year students(n=194) and 12% of the fourth-year students(n=190). On an institutional level the proportion of students answering all MCQ's correctly ranged from 2% to 54% at different universities. Eighty-one percent of students(n=3,031) wished for more BLS training in their ***: Factual knowledge of BLS is poor among medical students in the UK. There is a disparity in standards of knowledge across institutions and respondents indicating that they would like more training.
Irrigation infrastructure expansion threatens the diversity of freshwater fish *** infrastructure creates migration barriers which can block access to important nursery,feeding and spawning *** PDR is a landlocked cou...
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Irrigation infrastructure expansion threatens the diversity of freshwater fish *** infrastructure creates migration barriers which can block access to important nursery,feeding and spawning *** PDR is a landlocked country situated within the Lower Mekong River Basin where there is a substantial dependency on rice and fish for food,income and *** country is experiencing an unprecedented boom in irrigation infrastructure investment,with modernisation programs being implemented in every *** significant investment in infrastructure upgrades,and the potential impact on freshwater fish,little consideration has been given to fish passage *** 2008,we commenced a fish passage program in Lao *** intent of this case study is to outline the pivotal elements of the program of knowledge development and transfer,in the context of river connectivity and fisheries management in Lao *** also highlight challenges in international research in development and lessons learned.
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