Optical scattering angles and Bose-stimulated motion in cold atomic gas

Bose statistics imply a substantial enhancement at small angles for light scattering off a cold, Bose gas. The enhancement increases dramatically at the Bose-Einstein temperature. This phenomenon could be utilized to eliminate almost entirely the heating of the gas by a weak probe light beam.Comment: 9 pages (REVTeX) and 1 figure (ps); revisions: some new comments relevant to current experiments and one math typo; to appear in Physics Letters

Identificación de la raza 1 de la bacteria Pseudomonas solanacearum E.F. Sm. del tabaco (Nicotiana tabacum L.)

Se presentan los resultados de patogenicidad, purificación de la bacteria, pruebas físico-químicas e identificación por medio de los hospedantes diferenciales. Se colectó material con síntomas de dormidera (Pseudomonas solanacearum) en diferentes cultivos de tabaco de Girón (Santander), Espinal, Guamo y San Luis (Tolima). Se efectuaron aislamientos de trozos de tallo afectados utilizando papa-dextrosa-agar (PDA) y cloruro de tetrazolio (TZC) como medios de cultivo. Una vez purificada la bacteria, se efectuaron pruebas físico-químicas con este cultivo y con cultivos tipo de las razas 2 y 3. Por último se inocularon plantas de tabaco, plátano y tomate, con el cultivo purificado y las razas 2 y 3. Se comprobó que el aislamiento efectuado a partir de muestras de tabaco enfermo procedentes de Girón, correspondía a la raza 1 de la bacteria. De las muestras procedentes del Departamento del Tolima no se aisló organismo bacterial alguno sino colonias fungosas pertenecientes al género FusariumTabaco-Nicotiana tabacum L

Leading logarithms of the bb quark mass in inclusive B→XsγB\to X_s\gamma decay

Part of the order $\alpha_s$ correction to the inclusive $B\to X_s\,\gamma$ photon spectrum is enhanced by $\log(m_b^2/m_s^2)$. We discuss its origin and sum the corrections proportional to $[\alpha_s\log(m_b^2/\mu^2)]^n$ to all orders. These are the calculable leading logarithms in the parton fragmentation functions of a quark or gluon into a photon. Although the gluon fragmentation into a photon starts only at order $\alpha_s^2$, its contribution is of the same order as the $s$ quark's in the leading log sum. For not too small values of the photon energy, the resummation yields a moderate suppression. In the standard model, the coefficient of the operator whose matrix element gives rise to such terms is small. A measurement of the photon spectrum around $1\,$GeV would provide a theoretically clean determination of $C_8$, the Wilson coefficient of the $b\to s\,g$ operator.Comment: 12 pages revtex, 2 figures include

Marchitamiento bacterial (Moko) del plátano, causado por Pseudomonas solanacearum.

Se realizó un reconocimiento de una enfermedad cuya dispersión e incidencia están tomando características de epifitotia a lo largo del Valle del río Magdalena. Se hicieron aislamientos de exudados y suspensiones de frutos, seudotallos y raquis de material enfermo proveniente de 2 municipios del Tolima, utilizando como medio de cultivo el T2C (cloruro de tetrazolio) y se efectuaron pruebas de patogenicidad en plátano, tomate, papa y tabaco. Las siembras iniciales en medio T2C se caracterizaron por el crecimiento de gran número de colonias cuya morfología fué similar a la descrita para Pseudomonas solanacearum. Todas las solanáceas inoculadas presentaron síntomas de marchitez típica del daño causado por Pseudomonas, los colinos inoculados presentaron en el rizoma y en la parte central del seudotallo puntos pardo rojizos y negro en el tejido vascular, síntomas típicos causados por la enfermedad. En frutos (racimos) fuertemente atacados por la bacteria se pudieron aislar en medio PDA (papa-dextrosa-agar) patógenos secundarios como Gloesporium spp y Fusarium spp. Actualmente se adelantan estudios sobre medidas de control, hospedantes de la bacteria entre malezas comunes de los cultivos de plátano, y ensayos de resistencia entre variedades nacionales y extranjeras.Plátano-Musa sapientu

Evaluation of a process of implementation of a gestational diabetes nutrition model of care into practice

Aim: Poorly controlled gestational diabetes mellitus can result in negative pregnancy and delivery outcomes. A reduced need for insulin was documented in the validation of American gestational diabetes Nutrition Practice Guidelines, which recommend at least three dietitian visits. No Australian gestational diabetes mellitus nutrition guidelines exist. This paper evaluates the implementation of a dietetic model of care based on the American guidelines in an Australian hospital. Methods: The implementation plan consisted of a nine-month pre (usual care)/post (new model of care) design with a month for ‘integration’ across 2012–2013. Primary outcomes were uptake of the new dietetic model of care and requirement for pharmacotherapy. Results: Both phases ran for seven months; integration required four months. Pre-intervention, only one woman received a review appointment. Significantly more women received best-practice care post-implementation (P = 0.02); of the 162 women seen, 50.6% received two review appointments. As a result of heavy clinical demand, only 31.5% of the women seen post-implementation received an individual dietitian assessment and education session, deviating from best practice. Clinically relevant changes were seen in medication requirements with a decrease in women requiring pharmacological treatment (31.1% (pre); 26.9% (post)). The difference was more pronounced in women who received best-practice care (27.2% (no) vs 25.0% (yes)). Conclusions: This project successfully increased the proportion of women seen according to best practice. Service limitations impaired the delivery of optimal care. The present study illustrates the opportunities and challenges of conducting evidence-based implementation research in routine clinical care