Avancée de Diabrotica virgifera virgifera [Coleoptera : Chrysomelidae] dans les champs de maïs au Québec et collecte dans le soja à Ottawa, Ontario

La chrysomèle des racines du maïs de l’Ouest, Diabrotica virgifera virgifera, a été trouvée au Québec en septembre 2000 dans la région de la Montérégie. Ceci constitue une extension vers le nord de son aire de répartition. De plus, à Ottawa, quelques individus se sont développés à partir du soja. Ceci constitue la première mention de développement de cet insecte sur du soja au Canada.The western corn rootworm, Diabrotica virgifera virgifera, was found in the Monteregie region in the province of Quebec in September 2000. This finding constitutes a northern extension of the species distribution. Moreover, at Ottawa, some specimens were found developing from soybean plants. This constitutes the first mention of development of this insect on soybean in Canada

Orbital and spin physics in LiNiO2 and NaNiO2

We derive a spin-orbital Hamiltonian for a triangular lattice of e_g orbital degenerate (Ni^{3+}) transition metal ions interacting via 90 degree superexchange involving (O^{2-}) anions, taking into account the on-site Coulomb interactions on both the anions and the transition metal ions. The derived interactions in the spin-orbital model are strongly frustrated, with the strongest orbital interactions selecting different orbitals for pairs of Ni ions along the three different lattice directions. In the orbital ordered phase, favoured in mean field theory, the spin-orbital interaction can play an important role by breaking the U(1) symmetry generated by the much stronger orbital interaction and restoring the threefold symmetry of the lattice. As a result the effective magnetic exchange is non-uniform and includes both ferromagnetic and antiferromagnetic spin interactions. Since ferromagnetic interactions still dominate, this offers yet insufficient explanation for the absence of magnetic order and the low-temperature behaviour of the magnetic susceptibility of stoichiometric LiNiO_2. The scenario proposed to explain the observed difference in the physical properties of LiNiO_2 and NaNiO_2 includes small covalency of Ni-O-Li-O-Ni bonds inducing weaker interplane superexchange in LiNiO_2, insufficient to stabilize orbital long-range order in the presence of stronger intraplane competition between superexchange and Jahn-Teller coupling.Comment: 33 pages, 12 postscript figures, uses iopams.sty . This article features in New Journal of Physics as part of a Focus Issue on Orbital Physics - all contributions may be freely accessed at (http://stacks.iop.org/1367-2630/6/i=1/a=E05). The published version of this article may be found at http://stacks.iop.org/1367-2630/7/12

Energy metrics to evaluate the energy use and performance of water main assets

Managing aging infrastructure has become one of the greatest challenges for water utilities, particularly when faced with selecting the most critical pipes for rehabilitation from among the thousands of candidates. This paper presents a set of novel yet practical energy metrics that quantify energy interactions at the spatial resolution of individual water mains to help utilities identify pipes for rehabilitation. The metrics are demonstrated using a benchmark system and two large, complex systems. The results show that the majority of pipes have good energy performance but that an important minority of outlier pipes have low energy efficiency and high energy losses due to friction and leakage. Pumping and tank operations tend to drive energy efficiency and energy losses in pipes close to water sources, whereas diurnal variation in demand drives energy performance of mains located far away from water sources. The new metrics of energy lost to friction and energy lost to leakage can provide information on energy performance in a pipe that is complementary to the traditional measures of unit head loss and leakage flow

Effect of Stress on Viral–Bacterial Synergy in Bovine Respiratory Disease: Novel Mechanisms to Regulate Inflammation

The severity of bovine respiratory infections has been linked to a variety of factors, including environmental and nutritional changes, transportation, and social reorganization of weaned calves. Fatal respiratory infections, however, usually occur when a primary viral infection compromises host defences and enhances the severity of a secondary bacterial infection. This viral–bacterial synergy can occur by a number of different mechanisms and disease challenge models have been developed to analyse host responses during these respiratory infections. A primary bovine herpesvirus-1 (BHV-1) respiratory infection followed by a secondary challenge with Mannheimia haemolytica results in fatal bovine respiratory disease (BRD) and host responses to these two pathogens have been studied extensively. We used this disease model to demonstrate that stress significantly altered the viral–bacterial synergy resulting in fatal BRD. Functional genomic analysis revealed that BHV-1 infection enhanced toll-like receptors (TLR) expression and increased pro-inflammatory responses which contribute to the severity of a Mannheimia haemolytica infection. TLRs play a critical role in detecting bacterial infections and inducing pro-inflammatory responses. It is difficult to understand, however, how stress-induced corticosteroids could enhance this form of viral–bacterial synergy. Nuclear translocation of the glucocorticoid receptor activates cell signalling pathways which inhibit both TLR signalling and pro-inflammatory responses. The apparent conundrum between stress-induced corticosteroids and enhanced BRD susceptibility is discussed in terms of present data and previous investigations of stress and respiratory disease

Avaliação do Ensino de Empreendedorismo entre Estudantes Universitários por meio do Perfil Empreendedor

Entrepreneurship is a socioeconomic phenomenon that has been valued for its influence on the growth and development of regional and national economies. The main promoter of this phenomenon are entrepreneurs, subjects endowed with multiple features that make up their profiles. They are dynamic and results oriented, benefitting from the fruits of their own personal efforts. Entrepreneurial education is highlighted as one of the most efficient ways to promote an entrepreneurial culture and train new entrepreneurs. However, some difficulty has been observed in assessing the effectiveness of teaching and learning this subject. The objective of this study was to analyze, by means of multivariate techniques, an instrument whose function is to measure the learning of Entrepreneurship, verifying the change in entrepreneur profiles of 407 college students participating or not in an entrepreneurial training process. The results showed that students who participated in Entrepreneurship educational training activities showed significant changes in their entrepreneurial profiles. The main contributions showed growth in the Self-realization, Planner, Innovative and Risks Assumed dimensions

Hepatitis B Vaccine Antibody Response and the Risk of Clinical AIDS or Death

Whether seroresponse to a vaccine such as hepatitis B virus (HBV) vaccine can provide a measure of the functional immune status of HIV-infected persons is unknown.This study evaluated the relationship between HBV vaccine seroresponses and progression to clinical AIDS or death. (HR 3.40; 95% CI, 1.39–8.32).

Pre-Procedural Atorvastatin Mobilizes Endothelial Progenitor Cells: Clues to the Salutary Effects of Statins on Healing of Stented Human Arteries

OBJECTIVES: Recent clinical trials suggest an LDL-independent superiority of intensive statin therapy in reducing target vessel revascularization and peri-procedural myocardial infarctions in patients who undergo percutaneous coronary interventions (PCI). While animal studies demonstrate that statins mobilize endothelial progenitor cells (EPCs) which can enhance arterial repair and attenuate neointimal formation, the precise explanation for the clinical PCI benefits of high dose statin therapy remain elusive. Thus we serially assessed patients undergoing PCI to test the hypothesis that high dose Atorvastatin therapy initiated prior to PCI mobilizes EPCs that may be capable of enhancing arterial repair. METHODS AND RESULTS: Statin naïve male patients undergoing angiography for stent placement were randomized to standard therapy without Atorvastatin (n = 10) or treatment with Atorvastatin 80 mg (n = 10) beginning three days prior to stent implantation. EPCs were defined by flow cytometry (e.g., surface marker profile of CD45dim/34+/133+/117+). As well, we also enumerated cultured angiogenic cells (CACs) by standard in vitro culture assay. While EPC levels did not fluctuate over time for the patients free of Atorvastatin, there was a 3.5-fold increase in EPC levels with high dose Atorvastatin beginning within 3 days of the first dose (and immediately pre-PCI) which persisted at 4 and 24 hours post-PCI (p<0.05). There was a similar rise in CAC levels as assessed by in vitro culture. CACs cultured in the presence of Atorvastatin failed to show augmented survival or VEGF secretion but displayed a 2-fold increase in adhesion to stent struts (p<0.05). CONCLUSIONS: High dose Atorvastatin therapy pre-PCI improves EPC number and CAC number and function in humans which may in part explain the benefit in clinical outcomes seen in patients undergoing coronary interventions

Stimuli-responsive chitosan-starch injectable hydrogels combined with encapsulated adipose-derived stromal cells for articular cartilage regeneration

Tissue engineering strategies have been showing promising early results in articular cartilage lesions repair. Hydrogels based on natural origin polymers as chitosan glycerol-phosphate (CGP) thermosensitive formulation that can be implanted in a minimal invasive manner, represent a great promise as injectable scaffold choice for cartilage tissue engineering, but it lacks in mechanical properties. A different formulation, from which a firm texture gels results is, therefore, desirable. In this work we first aim to investigate the suitability of CGP to produce an injectable thermosensitive, pH-dependent solution, when combined with increasing concentrations of starch: 0.5% (I), 1% (II), and 1.5% (III). The data collected from the rheological measurements showed that the addition of starch to the CGP did not alter the transition temperature and confirmed the heating inducing gelation of all solutions, supporting the ability of these novel formulations to be applied as minimal invasive systems. The evaluation of the dynamic mechanical analysis of the hydrogels showed an increase in the storage modulus within increasing starch concentration, clearly demonstrating that best viscoelastic properties were obtained with the novel chitosan-starch based solution. The incorporation of starch also improved the degradation profile. All materials showed to be biocompatible through the cytotoxicity screening in vitro. These data suggested the potential of novel thermo-responsive chitosan-starch hydrogels to be used as injectable vehicles for cell delivery in cartilage tissue engineering applications. In a second phase, the potential of chitosan-b-glycerophosphate (CGP) and chitosan-bglycerophosphate- 1% starch (CST) hydrogels to induce chondrocytic differentiation and cartilage matrix accumulation were evaluated, as well as the influence of starch in the chondrogenesis of encapsulated adipose derived stromal (ADSC) cells. The ADSC were homogeneously encapsulated, remained viable, proliferated, and maintained the expression of typical chondrogenic markers genes, and deposited cartilage ECM molecules. Improved results were obtained within the novel CST constructs. The overall data suggest that chitosan-b-glycerophosphate-starch hydrogels could be considered for chondrogenic differentiation of adipose derived stromal cells for cartilage-engineered regeneration using minimal invasive techniques.The authors acknowledge the financial support to the Portuguese Foundation for Science and Technology (FCT) for the PhD fellowship to H. Sa-Lima (SFRH/BD/21779/2005) and for the Project PTDC/QUI/68804/2006; the European Union funded STREP Project HIPPOCRATES (NM3-CT-2003-505758); and the European NoE EXPERTISSUES (NMP3-CT-2004-500283)

Optostimulation of striatonigral terminals in substantia nigra induces dyskinesia that increases after L‐DOPA in a mouse model of Parkinson's disease

Background and Purpose: L-DOPA-induced dyskinesia (LID) remains a major complication of L-DOPA therapy in Parkinson's disease. LID is believed to result from inhibition of substantia nigra reticulata (SNr) neurons by GABAergic striatal projection neurons that become supersensitive to dopamine receptor stimulation after severe nigrostriatal degeneration. Here, we asked if stimulation of direct medium spiny neuron (dMSN) GABAergic terminals at the SNr can produce a full dyskinetic state similar to that induced by L-DOPA. Experimental Approach: Adult C57BL6 mice were lesioned with 6-hydroxydopamine in the medial forebrain bundle. Channel rhodopsin was expressed in striatonigral terminals by ipsilateral striatal injection of adeno-associated viral particles under the CaMKII promoter. Optic fibres were implanted on the ipsilateral SNr. Optical stimulation was performed before and 24 hr after three daily doses of L-DOPA at subthreshold and suprathreshold dyskinetic doses. We also examined the combined effect of light stimulation and an acute L-DOPA challenge. Key Results: Optostimulation of striatonigral terminals inhibited SNr neurons and induced all dyskinesia subtypes (optostimulation-induced dyskinesia [OID]) in 6-hydroxydopamine animals, but not in sham-lesioned animals. Additionally, chronic L-DOPA administration sensitised dyskinetic responses to striatonigral terminal optostimulation, as OIDs were more severe 24 hr after L-DOPA administration. Furthermore, L-DOPA combined with light stimulation did not result in higher dyskinesia scores than OID alone, suggesting that optostimulation has a masking effect on LID. Conclusion and Implications: This work suggests that striatonigral inhibition of basal ganglia output (SNr) is a decisive mechanism mediating LID and identifies the SNr as a target for managing LID.Fil: Keifman, Ettel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Fisiología y Biofísica Bernardo Houssay; Argentina. Consejo Superior de Investigaciones Científicas; EspañaFil: Ruiz De Diego, Irene. Consejo Superior de Investigaciones Científicas; EspañaFil: Pafundo, Diego Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Fisiología y Biofísica Bernardo Houssay; ArgentinaFil: Paz, Rodrigo Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Fisiología y Biofísica Bernardo Houssay; ArgentinaFil: Solís, Oscar. Consejo Superior de Investigaciones Científicas; EspañaFil: Murer, Mario Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Fisiología y Biofísica Bernardo Houssay; ArgentinaFil: Moratalla, Rosario. Consejo Superior de Investigaciones Científicas; Españ

Genomic Prevalence of Heterochromatic H3K9me2 and Transcription Do Not Discriminate Pluripotent from Terminally Differentiated Cells

Cellular differentiation entails reprogramming of the transcriptome from a pluripotent to a unipotent fate. This process was suggested to coincide with a global increase of repressive heterochromatin, which results in a reduction of transcriptional plasticity and potential. Here we report the dynamics of the transcriptome and an abundant heterochromatic histone modification, dimethylation of histone H3 at lysine 9 (H3K9me2), during neuronal differentiation of embryonic stem cells. In contrast to the prevailing model, we find H3K9me2 to occupy over 50% of chromosomal regions already in stem cells. Marked are most genomic regions that are devoid of transcription and a subgroup of histone modifications. Importantly, no global increase occurs during differentiation, but discrete local changes of H3K9me2 particularly at genic regions can be detected. Mirroring the cell fate change, many genes show altered expression upon differentiation. Quantitative sequencing of transcripts demonstrates however that the total number of active genes is equal between stem cells and several tested differentiated cell types. Together, these findings reveal high prevalence of a heterochromatic mark in stem cells and challenge the model of low abundance of epigenetic repression and resulting global basal level transcription in stem cells. This suggests that cellular differentiation entails local rather than global changes in epigenetic repression and transcriptional activity