Recent Trends in Water Clarity of Lake Pontchartrain

An analysis of Secchi disk transparency observations from 3 sites on the Lake Pontchartrain Causeway indicates that water clarity has increased at the north shore and mid-lake sites, but has not changed at the south shore site. Louisiana Department of Environmental Quality data from 1986 through 1995 were used in the analysis. Further analysis indicates that the increased transparency was not caused by changes in salinity or wind speed. The best explanation for the observed increase is the cessation of shell dredging in 1990

Recent Trends in Water Clarity of Lake Pontchartrain

An analysis of Secchi disk transparency observations from 3 sites on the Lake Pontchartrain Causeway indicates that water clarity has increased at the north shore and mid-lake sites, but has not changed at the south shore site. Louisiana Department of Environmental Quality data from 1986 through 1995 were used in the analysis. Further analysis indicates that the increased transparency was not caused by changes in salinity or wind speed. The best explanation for the observed increase is the cessation of shell dredging in 1990

Historic Trends in the Secchi Disk Transparency of Lake Pontchartrain

A major environmental concern about Lake Pontchartrain is an assumed long-term increase in turbidity based on Secchi disk transparency observations. Regression of the available data on Secchi disk transparency versus time (1953 through 1990) reveals a statistically significant decrease in transparency of about 40%. However, the data set is biased in that it does not adequately represent the seasonal effects of salinity and wind speed. Two analytical procedures were undertaken to determine the extent to which the apparent long-term decrease in transparency was dependent on the seasonal bias. One procedure involved seasonal adjustment of the data for the effects of salinity and wind speed. The other procedure was to remove the seasonal bias by constructing unbiased data sets. Seasonal adjustment for the effects of salinity and wind speed reduced the level of significance for the relationship between Secchi disk transparency and time from about 1% to about 10%. This result indicates that some of the apparent decrease in transparency in the original data is the result of inadequate representation of seasonal effects in the biased data set. In most years data are not available for all months with the result that the seasonal effects of salinity and wind speed are not adequately represented. When the bias was removed by constructing unbiased data sets, the data no longer supported the conclusion of a statistically significant change in Secchi disk transparency from 1953 to 1990; p \u3e 0.5

Données préliminaires sur l’exploitation des pangolins (Pholidota) autour du Parc National de Kahuzi-Biega, République Démocratique du Congo

Dans un contexte où la demande des écailles des pangolins pour la médicine traditionnelle chinoise ne cesse d’augmenter, ces animaux se trouvent de plus à plus braconner. Il est donc important que les études soient menées dans leur zone de répartition pour arriver à dégager les motivations de cette exploitation dans chaque zone. C’est dans cet angle que l’étude sur l’exploitation des pangolins et de leurs produits dérivés a été réalisée autour du parc national de Kahuzi-Biega avec pour objectif de dégager les différentes fins pour lesquelles ces animaux y sont exploités et identifier les différents acteurs intervenant dans ce domaine via l’information et les connaissances des riverains. La méthode d’enquête individuelle et collective a été conduite auprès de 116 personnes pendant une période de deux mois (mars et avril 2019) autour du Secteur Tshivanga et du Secteur Itebero. Les analyses comparatives, Khi-deux, Ficher et les analyses à correspondances multiples (ACM) ont été effectuées à l’aide du logiciel Past 3.2. Les résultats obtenus montrent que les pangolins sont principalement exploités pour l’alimentation et la médecine traditionnelles. Cependant, le trafic de leurs écailles a fait augmenter la demande dans la zone. Les demandeurs des écailles viennent principalement des grandes villes (Bukavu, Goma, Kisangani) et des certaines pays étrangers (Ouganda, Burundi, Tanzanie et les agents de la Mission des Nations-Unies pour la Stabilisation au Congo). Le commerce des écailles pour satisfaire la demande externe, bien qu’encore à ces débuts, vient menacer les pangolins dans cette zone où la chasse est strictement interdite. Ce commerce passe par des intermédiaires, dont les principaux sont les enfants du milieu.Mots clés : Étude préliminaire, exploitation, pangolins, Kahuzi-biega, RDC English Title: Preliminary data on the exploitation of Pangolins (Pholidota) about the National Park of Kahuzi-Biega, Democratic Republic of Congo (DRC)In a context where the demand for pangolin scales for traditional Chinese medicine continues to increase, these animals are increasingly being poached. It is therefore important that studies be carried out in their area of distribution in order to identify the motivations for this exploitation in each area. It is in this perspective that the study on the exploitation of pangolins and their by-products was carried out around the Kahuzi-Biega National Park with the aim of identifying the different purposes for which these animals are exploited there and to identify the different actors involved in this field through the information and knowledge of local residents. The individual and collective survey method was conducted among 116 people over a two-month period (March and April 2019) around the Tshivanga Sector and the Itebero Sector. Comparative, Chi-square, File and Multiple Correspondence Analysis (MCA) analyses were carried out using Past 3.2 software. The results obtained show that pangolins are mainly exploited for traditional food and medicine. However, the trafficking of their scales has increased demand in the area. The demand for the scales comes mainly from the big cities (Bukavu, Goma, Kisangani) and from some foreign countries (Uganda, Burundi, Tanzania and agents of the United Nations Stabilization Mission in Congo). The trade in scales to satisfy external demand, although still in its infancy, is threatening pangolins in this area where hunting is strictly prohibited. This trade goes through intermediaries, the main ones being local children.Keywords: Preliminary study, exploitation, pangolins, Kahuzi-biega, DRC

A cohort study of post-weaning multisystemic wasting syndrome and PCV2 in 178 pigs from birth to 14 weeks on a single farm in England

Our hypothesis was that pigs that develop post-weaning multisystemic wasting syndrome (PMWS) are detectable from an early age with signs of weight loss and other clinical and serological abnormalities. Therefore, the objective of this study was to investigate the temporally varying and fixed events linked with the clinical incidence of PMWS by comparing affected and unaffected pigs in a cohort of 178 male piglets. Piglets were enrolled at birth and examined each week. Samples of blood were collected at regular intervals. The exposures measured were porcine circovirus type 2 (PCV2) antibody titres in all 178 and PCV2 antigen in a subset of 75 piglets. We also observed piglet health and measured their weight, and a post-mortem examination was performed by an external laboratory on all pigs between 6 and 14 weeks of age that died. From the cohort, 14 (8%) pigs died from PMWS and 4% from other causes. A further 37 pigs between 6 and 14 weeks of age died from PMWS (30) and ileitis and other causes (7). PMWS was only apparent in pigs from 1 to 2 weeks before death when they wasted rapidly. There were no other characteristic clinical signs and no obvious gross clinical lesions post-mortem. There was no strong link with PCV2 antibody throughout life but PCV2 antigen level was higher from 4 to 6 weeks of age in pigs that died from PMWS compared with pigs that died from other causes

Mechanism of insulin gene regulation by the pancreatic transcription factor Pdx-1: Application of pre-mRNA analysis and chromatin immunoprecipitation to assess formation of functional transcriptional complexes

The homeodomain factor Pdx-1 regulates an array of genes in the developing and mature pancreas, but whether regulation of each specific gene occurs by a direct mechanism (binding to promoter elements and activating basal transcriptional machinery) or an indirect mechanism (via regulation of other genes) is unknown. To determine the mechanism underlying regulation of the insulin gene by Pdx-1, we performed a kinetic analysis of insulin transcription following adenovirus-mediated delivery of a small interfering RNA specific for pdx-1 into insulinoma cells and pancreatic islets to diminish endogenous Pdx-1 protein, insulin transcription was assessed by measuring both a long half-life insulin mRNA (mature mRNA) and a short half-life insulin pre-mRNA species by real-time reverse transcriptase-PCR. Following progressive knock-down of Pdx-1 levels, we observed coordinate decreases in pre-mRNA levels (to about 40% of normal levels at 72 h). In contrast, mature mRNA levels showed strikingly smaller and delayed declines, suggesting that the longer half-life of this species underestimates the contribution of Pdx-1 to insulin transcription. Chromatin immunoprecipitation assays revealed that the decrease in insulin transcription was associated with decreases in the occupancies of Pdx-1 and p300 at the proximal insulin promoter. Although there was no corresponding change in the recruitment of RNA polymerase II to the proximal promoter, its recruitment to the insulin coding region was significantly reduced. Our results suggest that Pdx-1 directly regulates insulin transcription through formation of a complex with transcriptional coactivators on the proximal insulin promoter. This complex leads to enhancement of elongation by the basal transcriptional machinery. © 2005 by The American Society for Biochemistry and Molecular Biology, Inc

Lensing at cosmological scales: a test of higher dimensional gravity

Recent developments in gravitational lensing astronomy have paved the way to genuine mappings of the gravitational potential at cosmological scales. We stress that comparing these data with traditional large scale structure surveys will provide us with a test of gravity at such scales. These constraints could be of great importance in the framework of higher dimensional cosmological models.Comment: 4 pages, latex, 3 figure

Transitions between Inherent Structures in Water

The energy landscape approach has been useful to help understand the dynamic properties of supercooled liquids and the connection between these properties and thermodynamics. The analysis in numerical models of the inherent structure (IS) trajectories -- the set of local minima visited by the liquid -- offers the possibility of filtering out the vibrational component of the motion of the system on the potential energy surface and thereby resolving the slow structural component more efficiently. Here we report an analysis of an IS trajectory for a widely-studied water model, focusing on the changes in hydrogen bond connectivity that give rise to many IS separated by relatively small energy barriers. We find that while the system \emph{travels} through these IS, the structure of the bond network continuously modifies, exchanging linear bonds for bifurcated bonds and usually reversing the exchange to return to nearly the same initial configuration. For the 216 molecule system we investigate, the time scale of these transitions is as small as the simulation time scale ($\approx 1$ fs). Hence for water, the transitions between each of these IS is relatively small and eventual relaxation of the system occurs only by many of these transitions. We find that during IS changes, the molecules with the greatest displacements move in small ``clusters'' of 1-10 molecules with displacements of $\approx 0.02-0.2$ nm, not unlike simpler liquids. However, for water these clusters appear to be somewhat more branched than the linear ``string-like'' clusters formed in a supercooled Lennar d-Jones system found by Glotzer and her collaborators.Comment: accepted in PR

Diffusion of gold nanoclusters on graphite

We present a detailed molecular-dynamics study of the diffusion and coalescence of large (249-atom) gold clusters on graphite surfaces. The diffusivity of monoclusters is found to be comparable to that for single adatoms. Likewise, and even more important, cluster dimers are also found to diffuse at a rate which is comparable to that for adatoms and monoclusters. As a consequence, large islands formed by cluster aggregation are also expected to be mobile. Using kinetic Monte Carlo simulations, and assuming a proper scaling law for the dependence on size of the diffusivity of large clusters, we find that islands consisting of as many as 100 monoclusters should exhibit significant mobility. This result has profound implications for the morphology of cluster-assembled materials

Implementing evidence-based recommended practices for the management of patients with mild traumatic brain injuries in Australian emergency care departments: study protocol for a cluster randomised controlled trial

Background: Mild head injuries commonly present to emergency departments. The challenges facing clinicians in emergency departments include identifying which patients have traumatic brain injury, and which patients can safely be sent home. Traumatic brain injuries may exist with subtle symptoms or signs, but can still lead to adverse outcomes. Despite the existence of several high quality clinical practice guidelines, internationally and in Australia, research shows inconsistent implementation of these recommendations. The aim of this trial is to test the effectiveness of a targeted, theory- and evidence-informed implementation intervention to increase the uptake of three key clinical recommendations regarding the emergency department management of adult patients (18 years of age or older) who present following mild head injuries (concussion), compared with passive dissemination of these recommendations. The primary objective is to establish whether the intervention is effective in increasing the percentage of patients for which appropriate post-traumatic amnesia screening is performed. Methods/design: The design of this study is a cluster randomised trial. We aim to include 34 Australian 24-hour emergency departments, which will be randomised to an intervention or control group. Control group departments will receive a copy of the most recent Australian evidence-based clinical practice guideline on the acute management of patients with mild head injuries. The intervention group will receive an implementation intervention based on an analysis of influencing factors, which include local stakeholder meetings, identification of nursing and medical opinion leaders in each site, a train-the-trainer day and standardised education and interactive workshops delivered by the opinion leaders during a 3 month period of time. Clinical practice outcomes will be collected retrospectively from medical records by independent chart auditors over the 2 month period following intervention delivery (patient level outcomes). In consenting hospitals, eligible patients will be recruited for a follow-up telephone interview conducted by trained researchers. A cost-effectiveness analysis and process evaluation using mixed-methods will be conducted. Sample size calculations are based on including 30 patients on average per department. Outcome assessors will be blinded to group allocation