796 research outputs found
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
Yves Bélanger, Pierre Fournier, L’entreprise québecoise, Développement historique et dynamique, contemporain, Québec, Hurtubise HMH, Cahiers du Québec/Science politique, 1987, 187 p.
Crystallization in suspensions of hard spheres: A Monte Carlo and Molecular Dynamics simulation study
The crystallization of a metastable melt is one of the most important non
equilibrium phenomena in condensed matter physics, and hard sphere colloidal
model systems have been used for several decades to investigate this process by
experimental observation and computer simulation. Nevertheless, there is still
an unexplained discrepancy between simulation data and experimental nucleation
rate densities. In this paper we examine the nucleation process in hard spheres
using molecular dynamics and Monte Carlo simulation. We show that the
crystallization process is mediated by precursors of low orientational
bond-order and that our simulation data fairly match the experimental data
sets
The Interrelationship between Sensorimotor Deficits and Maladaptive Behavior in the Classroom
Mainstreaming special education students has created challenges for teachers, resulting in significant lesson time allocated to classroom disruptions related to maladaptive behavior. This correlational study examined the extent to which specific sensorimotor deficits predict maladaptive behavior among special education students (aged 8-12 years) based on archival data of teacher assessments in New Zealand. Piaget’s cognitive and affective development theory was used as the theoretical foundation. Results from standard multiple regression demonstrated that higher levels of sensorimotor deficits (vision, touch, taste and smell, body awareness, balance and motion) predicted high levels of maladaptive behavior (internalizing, externalizing, and overall maladaptive behavior indices); similarly, higher deficits in taste and smell predicted low levels of adaptive behavior. These results may lead to positive social change by stressing the importance of early sensory assessment among young school children. In addition, the results may also be used to improve interventions or programs designed to reduce maladaptive behavior in the classroom, reducing teachers’ time devoted to managing maladaptive behavior and improving special education students\u27 mental health
The Interrelationship between Sensorimotor Deficits and Maladaptive Behavior in the Classroom
Mainstreaming special education students has created challenges for teachers, resulting in significant lesson time allocated to classroom disruptions related to maladaptive behavior. This correlational study examined the extent to which specific sensorimotor deficits predict maladaptive behavior among special education students (aged 8-12 years) based on archival data of teacher assessments in New Zealand. Piaget’s cognitive and affective development theory was used as the theoretical foundation. Results from standard multiple regression demonstrated that higher levels of sensorimotor deficits (vision, touch, taste and smell, body awareness, balance and motion) predicted high levels of maladaptive behavior (internalizing, externalizing, and overall maladaptive behavior indices); similarly, higher deficits in taste and smell predicted low levels of adaptive behavior. These results may lead to positive social change by stressing the importance of early sensory assessment among young school children. In addition, the results may also be used to improve interventions or programs designed to reduce maladaptive behavior in the classroom, reducing teachers’ time devoted to managing maladaptive behavior and improving special education students\u27 mental health
Assessing the Need for Adjuvant Chemotherapy After Stereotactic Body Radiation Therapy in Early-stage Non-small Cell Lung Carcinoma.
Surgery remains the standard treatment for medically operable patients with early-stage non-small cell lung carcinoma (NSCLC). Following surgical resection, adjuvant chemotherapy is recommended for large tumors >4 cm. For unfit patients, stereotactic body radiation therapy (SBRT) has emerged as an excellent alternative to surgery. This study aims to assess patterns of recurrence and discuss the role of chemotherapy after SBRT for NSCLC.
We reviewed patients treated with SBRT for primary early-stage NSCLC between 2009 and 2015. Total target doses were between 50 and 60 Gy administered in three to eight fractions. All patients had a staging fluorodeoxyglucose (FDG) positron emission tomography (PET) integrated with computed tomography (CT) scan, and histologic confirmation was obtained whenever possible. Mediastinal staging was performed if lymph node involvement was suspected on CT or PET/CT. Survival outcomes were estimated using the Kaplan-Meier method.
Among the 559 early-stage NSCLC patients treated with SBRT, 121 patients were stage T2N0. The one-year and three-year overall survival rates were 88% and 70%, respectively, for patients with T2 disease, compared to 95% and 81%, respectively, for the T1 patients (p<0.05). The one-year and three-year local control rates were equal in both groups (98% and 91%, respectively). In T2 patients, 25 (21%) presented a relapse, among which 21 (84%) were nodal or distant. The median survival of T2N0 patients following a relapse was 11 months.
Lung SBRT provides high local control rates, even for larger tumors. When patients relapse, the majority of them do so at regional or distant sites. These results raise the question as to whether adjuvant treatment should be considered following SBRT for larger tumors
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
Occurrence of Legionella in groundwater: an ecological study
Abstract The natural habitat of Legionella is the water environment. Little is known about their presence in groundwaters in spite of the fact that many millions around the globe regularly rely on groundwaters. This pilot study was aimed at evaluating the occurrence of Legionella in groundwater samples (water and biofilms) collected from various sites. Water and biofilm samples from selected groundwater sources were examined for Legionella using culture media (selective and non-selective) and a semi-nested PCR assay. Innovative approaches such as immunomagnetic separation (IMS) in combination with cultivation and flow cytometry were also evaluated. The findings available thus far show that (a) Legionella could be readily recovered from groundwater samples by cultivation even though their numbers showed considerable variations, (b) surprisingly, the PCR methodology was not yet as sensitive as cultivation and (c) flow cytometry was not directly applicable on natural samples because of debris and the high number of heterotrophic associated microflora from which some members were likely to cross-react with the monoclonal antibody used for separation procedures (IMS)
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