On the Role of Metal Contaminants in Catalyses with FeCl

Warning: Catalyzed N-, O-, and C-arylation reactions ascribed to FeCl3 can instead result from catalysis by trace quantities of copper salts.Fonds der Chemischen Industrie (Germany)National Institutes of Health (U.S.) (GM46059)National Institutes of Health (U.S.) (58160

Acute reversible inactivation of the bed nucleus of stria terminalis induces antidepressant-like effect in the rat forced swimming test

<p>Abstract</p> <p>Background</p> <p>The bed nucleus of stria terminalis (BNST) is a limbic forebrain structure involved in hypothalamo-pituitary-adrenal axis regulation and stress adaptation. Inappropriate adaptation to stress is thought to compromise the organism's coping mechanisms, which have been implicated in the neurobiology of depression. However, the studies aimed at investigating BNST involvement in depression pathophysiology have yielded contradictory results. Therefore, the objective of the present study was to investigate the effects of temporary acute inactivation of synaptic transmission in the BNST by local microinjection of cobalt chloride (CoCl₂) in rats subjected to the forced swimming test (FST).</p> <p>Methods</p> <p>Rats implanted with cannulae aimed at the BNST were submitted to 15 min of forced swimming (pretest). Twenty-four hours later immobility time was registered in a new 5 min forced swimming session (test). Independent groups of rats received bilateral microinjections of CoCl₂(1 mM/100 nL) before or immediately after pretest or before the test session. Additional groups received the same treatment and were submitted to the open field test to control for unspecific effects on locomotor behavior.</p> <p>Results</p> <p>CoCl₂injection into the BNST before either the pretest or test sessions reduced immobility in the FST, suggesting an antidepressant-like effect. No significant effect of CoCl₂was observed when it was injected into the BNST immediately after pretest. In addition, no effect of BNST inactivation was observed in the open field test.</p> <p>Conclusion</p> <p>These results suggest that acute reversible inactivation of synaptic transmission in the BNST facilitates adaptation to stress and induces antidepressant-like effects.</p

Human Social Behavior and Demography Drive Patterns of Fine-Scale Dengue Transmission in Endemic Areas of Colombia

Dengue is known to transmit between humans and A. aegypti mosquitoes living in neighboring houses. Although transmission is thought to be highly heterogeneous in both space and time, little is known about the patterns and drivers of transmission in groups of houses in endemic settings. We carried out surveys of PCR positivity in children residing in 2-block patches of highly endemic cities of Colombia. We found high levels of heterogeneity in PCR positivity, varying from less than 30% in 8 of the 10 patches to 56 and 96%, with the latter patch containing 22 children simultaneously PCR positive (PCR22) for DEN2. We then used an agent-based model to assess the likely eco-epidemiological context of this observation. Our model, simulating daily dengue dynamics over a 20 year period in a single two block patch, suggests that the observed heterogeneity most likely derived from variation in the density of susceptible people. Two aspects of human adaptive behavior were critical to determining this density: external social relationships favoring viral introduction (by susceptible residents or infectious visitors) and immigration of households from non-endemic areas. External social relationships generating frequent viral introduction constituted a particularly strong constraint on susceptible densities, thereby limiting the potential for explosive outbreaks and dampening the impact of heightened vectorial capacity. Dengue transmission can be highly explosive locally, even in neighborhoods with significant immunity in the human population. Variation among neighborhoods in the density of local social networks and rural-to-urban migration is likely to produce significant fine-scale heterogeneity in dengue dynamics, constraining or amplifying the impacts of changes in mosquito populations and cross immunity between serotypes

Descomposición de hojarasca de especies nativas y exóticas en un humedal boscoso de agua dulce de Chile

Decomposition of leaf litter is a fundamental process for the functioning of forested wetlands. The rapid increment of forest&nbsp;plantations has involved a greater contribution of leaf litter of exotic origin to these ecosystems. The decomposition rate&nbsp;between leaf litter of native and exotic origin in a forested wetland of the Mediterranean zone of Chile was compared, as&nbsp;well as the contribution of bacteria and macroinvertebrate to this process. It was determined that the decomposition rate of&nbsp;the leaf litter presented signifi cant differences (p &lt; 0.05) between species, being faster in those of non-native origin. This&nbsp;could be due to differences in ecophysiological aspects of the leaves like the presence of chemical compounds such as&nbsp;waxes or oils. Both analyzed communities were relevant in the studied process. However, bacteria contributed mostly to&nbsp;the decomposition of both types of leaves. The implications of the physical and chemical characteristics of the leaves and&nbsp;the water on the processing of the foliar material are discussed.En los humedales boscosos, la descomposición de la hojarasca es un proceso fundamental para su funcionamiento. El&nbsp;rápido incremento de las plantaciones forestales ha implicado un mayor aporte de hojarasca de origen exótico a estos&nbsp;ecosistemas. Se comparó la tasa de descomposición entre hojarasca de origen nativo y exótico en un humedal boscoso de&nbsp;la zona Mediterránea de Chile, así como la contribución de las bacterias y macroinvertebrados a este proceso. Se determinó&nbsp;que la tasa de descomposición de la hojarasca presentó diferencias signifi cativas entre las diferentes especies (p &lt; 0,05),&nbsp;siendo más rápido en especies de origen exótico. Esto podría ser dado por diferencias en algunos aspectos ecofi siológicos&nbsp;de las hojas como la presencia de compuestos químicos tales como ceras o aceites. Ambas comunidades analizadas&nbsp;fueron relevantes en el proceso estudiado. Sin embargo, las bacterias contribuyeron mayormente a la descomposición de&nbsp;ambos tipos de hojas. Se discuten las implicaciones de las características físicas y químicas de las hojas y el agua en el&nbsp;procesamiento del material foliar

Overall survival analyses of female malignancies in Southern Brazil during 2008–2017: A closer look at breast, cervical and ovarian cancer

Background: The aim of this study was to report the overall survival and baseline factors associated with OS for breast, cervical and ovarian cancer in Florianópolis, Southern Brazil, a region with quality-of-life indicators comparable to high-income countries. Methods: Cohort study was performed from probabilistic record linkage of the Mortality Information System and the Population-based cancer registry of Florianópolis. It was included breasts, cervical and ovarian cancer diagnosis during the period of 2008–2012 with a follow up of 60 months. Cox regression and Kaplan-Meier method were used for associations with overall survival and risk factors. Findings: 1857 cases of the three malignancies were included in the analysis. We identified 202 deaths in breast cancer subjects, 53 for cervical cancer and 51 for ovarian cancer. Metastatic disease at diagnosis was present in 31%, 9.6%, and 55% of the cases, respectively. Overall survival was statistically correlated with age, educational level and stage for breast cancer; age and stage for cervical cancer; age and stage for ovarian cancer. Interpretation: Metastatic disease and age are the main prognostic factors for the malignancies studied, as they were associated with both overall survival and risk of death. Better screening and preventive tests for early diagnosis are needed. Funding: Support of Research and Innovation in the State of Santa Catarina, Research Program for the Unified Health System (FAPESC/MS-DECIT/CNPQ/SES-SC-PPSUS); the Brazilian National Research Council (CNPq); and the Coordination for the Improvement of Higher Education Personnel (CAPES)

Does lending behaviour of banks in emerging economies vary by ownership? Evidence from the Indian banking sector

While much has been discussed about the relationship between ownership and financial performance of banks in emerging markets, literature about cross-ownership differences in credit market behaviour of banks in emerging economies is sparse. Using bank-level data from India, and a portfolio-choice model, for nine years (1995-96 to 2003-04), we examine banks’ behaviour in the context of emerging credit markets. Our results indicate that, in India, the data for the domestic banks fit well the aforementioned portfolio-choice model, especially for private banks, but the model cannot explain the behaviour of foreign banks. In general, allocation of assets between risk-free government securities and risky credit is affected by past allocation patterns, stock exchange listing (for private banks), risk averseness of banks, regulations regarding treatment of NPA, and ability of banks to recover doubtful credit. It is also evident that banks deal with changing levels of systematic risk by altering the ratio of securitized to non-securitized credit. These results have implications for disbursal of credit to small and medium enterprises in India

Aprender a ser maestra. Perplejidades y paradojas

En un contexto caracterizado por la volatilidad de la información, la incertidumbre sobre el futuro, y la complejidad y ambigüedad del mundo educativo, los docentes de Enseñanza Infantil y Primaria viven su trabajo con perplejidad. Convertirse en educador implica adentrarse en una permanente renovación: de actividades, de objetivos y de relaciones con la comunidad. Se impone una renovación metodológica

Aprender a enseñar: La constitución de la identidad del profesor en la educación infantil y primaria

El estudio acerca de la construcción de la identidad del profesor en los últimos 20 años ha mostrado la importancia de la formación y de las primeras experiencias docentes para el proceso de aprender a ser profesor. Las evidencias recogidas mediante el análisis de 23 microetnografías y 13 grupos focales, en que han participado un total de 88 profesores, siete de ellos especialistas en Educación Física, nos ha permitido explorar los componentes macro, meso y microsistemas en que los profesores interactúan y dan sentido a su aprender a enseñar. La discusión y contextualización de las experiencias de los docentes en relación a: (a) el ingreso a la formación, (b) la experiencia de la formación inicial y permanente, (c) el concepto de conocimiento y aprendizaje y (d) cómo han aprendido a enseñar, pone de manifiesto la complejidad de ser docente en los días actuales y nos posibilita elaborar recomendaciones para la mejora de la formación y de la inserción en las escuelas

Single-Atom Gating of Quantum State Superpositions

The ultimate miniaturization of electronic devices will likely require local and coherent control of single electronic wavefunctions. Wavefunctions exist within both physical real space and an abstract state space with a simple geometric interpretation: this state space--or Hilbert space--is spanned by mutually orthogonal state vectors corresponding to the quantized degrees of freedom of the real-space system. Measurement of superpositions is akin to accessing the direction of a vector in Hilbert space, determining an angle of rotation equivalent to quantum phase. Here we show that an individual atom inside a designed quantum corral can control this angle, producing arbitrary coherent superpositions of spatial quantum states. Using scanning tunnelling microscopy and nanostructures assembled atom-by-atom we demonstrate how single spins and quantum mirages can be harnessed to image the superposition of two electronic states. We also present a straightforward method to determine the atom path enacting phase rotations between any desired state vectors. A single atom thus becomes a real space handle for an abstract Hilbert space, providing a simple technique for coherent quantum state manipulation at the spatial limit of condensed matter.Comment: Published online 6 April 2008 in Nature Physics; 17 page manuscript (including 4 figures) + 3 page supplement (including 2 figures); supplementary movies available at http://mota.stanford.ed