Side chain polysiloxanes with phthalocyanine moieties

Side chain polysiloxane with 5-(pentyloxy)-3-methyloxy-9,10,16,17,23,24-hexakis(octenyloxy)phthalocyanine moieties is synthesized by hydrosilylation reaction. The phase behavior and thermooptical properties of the polysiloxane and starting 2-(pent-4-enyloxy)-3-methyloxy-9,10,16,17,23,24-hexakis(octenyloxy)phthalocyanine is examined by POM (Polarizing optical microscopy), TOA (thermooptical analysis), DSC (differential scanning calorimetry), AFM (atomic force microscopy) and SAXS (small angle X-ray scattering) studies. The effect of the attachment of phthalocyanine to polysiloxane chains over phase transitions and phase morphology is discussed in details

Mapping suitable great ape habitat in and around the Lobéké National Park, South-East Cameroon

Abstract As a result of extensive data collection efforts over the last 20?30 years, there is quite a good understanding of the large-scale geographic distribution and range limits of African great apes. However, as human activities increasingly fragment great ape spatial distribution, a better understanding of what constitutes suitable great ape habitat is needed to inform conservation and resource extraction management. Chimpanzees (Pan troglodytes troglodytes) and gorillas (Gorilla gorilla gorilla) inhabit the Lobéké National Park and its surrounding forest management units (FMUs) in South-East Cameroon. Both park and neighboring forestry concessions require reliable evidence on key factors driving great ape distribution for their management plans, yet this information is largely missing and incomplete. This study aimed at mapping great ape habitat suitability in the area and at identifying the most influential predictors among three predictor categories, including landscape predictors (dense forest, swampy forest, distance to water bodies, and topography), human disturbance predictors (hunting, deforestation, distance to roads, and population density), and bioclimatic predictor (annual precipitation). We found that about 63% of highly to moderately suitable chimpanzee habitat occurred within the Lobéké National Park, while only 8.4% of similar habitat conditions occurred within FMUs. For gorillas, highly and moderately suitable habitats occurred within the Lobéké National Park and its surrounding FMUs (82.6% and 65.5%, respectively). Key determinants of suitable chimpanzee habitat were hunting pressure and dense forest, with species occurrence probability optimal at relatively lower hunting rates and at relatively high-dense forest areas. Key determinants of suitable gorilla habitat were hunting pressure, dense forests, swampy forests, and slope, with species occurrence probability optimal at relatively high-dense and swampy forest areas and at areas with mild slopes. Our findings show differential response of the two ape species to forestry activities in the study area, thus aligning with previous studies

Genetic characterization of clinical and agri-food isolates of multi drug resistant Salmonella enterica serovar Heidelberg from Canada

<p>Abstract</p> <p>Background</p> <p><it>Salmonella enterica </it>serovar Heidelberg ranks amongst the most prevalent causes of human salmonellosis in Canada and an increase in resistance to extended spectrum cephalosporins (ESC) has been observed by the Canadian Integrated Program for Antimicrobial Resistance Surveillance. This study examined the genetic relationship between <it>S</it>. Heidelberg isolates from livestock, abattoir, retail meat, and clinical human specimens to determine whether there was a link between the emergence of MDR <it>S</it>. Heidelberg in chicken agri-food sources and the simultaneous increase of MDR <it>S</it>. Heidelberg in human clinical samples.</p> <p>Results</p> <p>Chromosomal genetic homogeneity was observed by pulsed-field gel electrophoresis (PFGE), DNA sequence-based typing (SBT) and DNA microarray-based comparative genomic hybridization (CGH). Sixty one percent of isolates were indistinguishable by PFGE conducted using <it>Xba</it>I and <it>Bln</it>I restriction enzymes. An additional 15% of isolates had PFGE patterns that were closely related to the main cluster. SBT did not identify DNA polymorphisms and CGH revealed only genetic differences between the reference <it>S</it>. Typhimurium strain and <it>S</it>. Heidelberg isolates. Genetic variation observed by CGH between <it>S</it>. Heidelberg isolates could be attributed to experimental variation. Alternatively, plasmid content was responsible for differences in antimicrobial susceptibility, and restriction fragment length polymorphism (RFLP) analyses followed by replicon typing identified two divergent plasmid types responsible for ESC resistance.</p> <p>Conclusion</p> <p>Due to the overall limited genetic diversity among the isolates, it was not possible to identify variable traits that would be suitable for source tracking between human and agri-food isolates of <it>S</it>. Heidelberg in Canada.</p

Limited genetic diversity in Salmonella enterica Serovar Enteritidis PT13

<p>Abstract</p> <p>Background</p> <p><it>Salmonella enterica </it>serovar Enteritidis has emerged as a significant foodborne pathogen throughout the world and is commonly characterized by phage typing. In Canada phage types (PT) 4, 8 and 13 predominate and in 2005 a large foodborne PT13 outbreak occurred in the province of Ontario. The ability to link strains during this outbreak was difficult due to the apparent clonality of PT13 isolates in Canada, as there was a single dominant pulsed-field gel electrophoresis (PFGE) profile amongst epidemiologically linked human and food isolates as well as concurrent sporadic strains. The aim of this study was to perform comparative genomic hybridization (CGH), DNA sequence-based typing (SBT) genomic analyses, plasmid analyses, and automated repetitive sequence-based PCR (rep-PCR) to identify epidemiologically significant traits capable of subtyping <it>S</it>. Enteritidis PT13.</p> <p>Results</p> <p>CGH using an oligonucleotide array based upon chromosomal coding sequences of <it>S. enterica </it>serovar Typhimurium strain LT2 and the <it>Salmonella </it>genomic island 1 successfully determined major genetic differences between <it>S</it>. Typhimurium and <it>S</it>. Enteritidis PT13, but no significant strain-to-strain differences were observed between <it>S</it>. Enteritidis PT13 isolates. Individual loci (<it>safA </it>and <it>fliC</it>) that were identified as potentially divergent in the CGH data set were sequenced in a panel of <it>S</it>. Enteritidis strains, and no differences were detected between the PT13 strains. Additional sequence-based typing was performed at the <it>fimA</it>, <it>mdh</it>, <it>manB</it>, <it>cyaA</it>, <it>citT</it>, <it>caiC</it>, <it>dmsA</it>, <it>ratA </it>and STM0660 loci. Similarly, no diversity was observed amongst PT13 strains. Variation in plasmid content between PT13 strains was observed, but macrorestriction with B<it>gl</it>II did not identify further differences. Automated rep-PCR patterns were variable between serovars, but <it>S</it>. Enteritidis PT13 strains could not be differentiated.</p> <p>Conclusion</p> <p>None of the methods identified any significant variation between PT13 strains. Greater than 11,300 base pairs of sequence for each of seven <it>S</it>. Enteritidis PT13 strains were analyzed without detecting a single polymorphic site, although diversity between different phage types of <it>S</it>. Enteritidis was observed. These data suggest that Canadian <it>S</it>. Enteritidis PT13 strains are highly related genetically.</p

Application of network traffic flow model to road maintenance

The study shows how the evolution of two-way traffic flows on a local highway network can be predicted over time using a network-level traffic flow model (NTFM) to model both urban and motorway road networks. After a brief review of the main principles of the NTFM and its associated sub-models, the paper describes how a maintenance worksite can be modelled using a roadwork-node sub-model and a network solution routine in the NTFM. In order to model the two-way traffic flow in the road network, an iterative simulation method is used to generate the evolution of dependent traffic flows and queues. The NTFM has been applied to model the traffic characteristics and the effects of maintenance activities on the local Loughborough–Nottingham highway network. The study has demonstrated that the methodology is useful in selecting various worksite arrangements in order to reduce the effects of maintenance on road users

Hyperglycemia Is Associated With Enhanced Thrombin Formation, Platelet Activation, and Fibrin Clot Resistance to Lysis in Patients With Acute Coronary Syndrome

OBJECTIVE—Acute hyperglycemia on admission for acute coronary syndrome worsens the prognosis in patients with and without known diabetes. Postulated mechanisms of this observation include prothrombotic effects. The aim of this study was to evaluate the effect of elevated glucose levels on blood clotting in acute coronary syndrome patients

A π-Extended Donor-Acceptor-Donor Triphenylene Twin linked via a Pyrazine-bridge

Beta-amino triphenylenes can be accessed via palladium catalyzed amination of the corresponding triflate using benzophe-none imine. Transformation of amine 6 to benzoyl amide 18 is also straightforward and its wide mesophase range demon-strates that the new linkage supports columnar liquid crystal formation. Amine 6 also undergoes clean aerobic oxidation to give a new twinned structure linked through an electron-poor pyrazine ring. The new discotic liquid crystal motif contains donor and acceptor fragments, and is more oval in shape rather than disk-like. It forms a wide range columnar mesophase. Absorption spectra are strong and broad; emission is also broad and occurs with a Stokes shift of ca. 0.7 eV, indicative of charge-transfer characte

Code Reuse in Open Source Software

Code reuse is a form of knowledge reuse in software development that is fundamental to innovation in many fields. However, to date there has been no systematic investigation of code reuse in open source software projects. This study uses quantitative and qualitative data gathered from a sample of six open source software projects to explore two sets of research questions derived from the literature on software reuse in firms and open source software development. We find that code reuse is extensive across the sample and that open source software developers, much like developers in firms, apply tools that lower their search costs for knowledge and code, assess the quality of software components, and have incentives to reuse code. Open source software developers reuse code because they want to integrate functionality quickly, because they want to write preferred code, because they operate under limited resources in terms of time and skills, and because they can mitigate development costs through code reuse

An empirical study of software reuse by experts in object-oriented design

This paper presents an empirical study of the software reuse activity by expert designers in the context of object-oriented design. Our study focuses on the three following aspects of reuse : (1) the interaction between some design processes, e.g. constructing a problem representation, searching for and evaluating solutions, and reuse processes, i.e. retrieving and using previous solutions, (2) the mental processes involved in reuse, e.g. example-based retrieval or bottom-up versus top-down expanding of the solution, and (3) the mental representations constructed throughout the reuse activity, e.g. dynamic versus static representations. Some implications of these results for the specification of software reuse support environments are discussed