Derivados y crecimiento económico: Nexos y evidencia el impacto de los derivados financieros en la economía real

Este trabajo estudia el nexo entre el desarrollo de los mercados de derivados y el crecimiento económico. Reconociendo que la falta de datos obstaculiza cualquier análisis econométrico robusto, este trabajo establece y verifica empíricamente esos nexos adoptando técnicas de correlación estadística utilizando datos de los mercados desarrollados y emergentes durante el período más grande posible y prueba la presencia de un quiebre estructural después de la crisis del 2008-2009. El resultado general es que los derivados están correlacionados positivamente con el crecimiento económico, en particular a través del canal de inversión y comercio internacional. Otro resultado es que dicha relación es cóncava entre el crecimiento y los derivados en el caso de los países desarrollados.This paper studies the links between the development of derivative markets and economic growth. By acknowledging the shortness of samples hindering any robust econometric analysis, it sets out and empirically checks those links, adopting statistical correlation techniques. It uses developed and emerging economy data over the most extensive period possible and tests for the presence of a structural break after the 2008-2009 crisis. The general result is that derivatives are positively correlated with economic growth, in particular, through the investment and international trade links. Another general result is that there is a concave relationship between growth and derivatives in the case of developed countries.Fil: Grandes, Martin. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Económicas; ArgentinaFil: Lema, Diego. Universidad de Buenos Aires. Facultad de Ciencias Económicas; Argentin

Assessing local structural perturbations in proteins

BACKGROUND: Protein structure research often deals with the comparison of two or more structures of the same protein, for instance when handling alternative structure models for the same protein, point mutants, molecule movements, structure predictions, etc. Often the difference between structures is small, restricted to a local neighborhood, and buried in structural "noise" due to trivial differences resulting from experimental artifacts. In such cases, whole-structure comparisons by means of structure superposition may be unsatisfactory and researchers have to perform a tedious process of manually superposing different segments individually and/or use different frames of reference, chosen roughly by educated guessing. RESULTS: We have developed an algorithm to compare local structural differences between alternative structures of the same protein. We have implemented the algorithm through a computer program that performs the numerical evaluation and allows inspecting visually the results of the structure comparison. We have tested the algorithm on different kinds of model systems. Here we present the algorithm and some results to illustrate its characteristics. CONCLUSION: This program may provide an insight into the local structural changes produced in a protein structure by different interactions or modifications. It is convenient for the general user and it can be applied to standard or specific tasks on protein structure research

Knowledge and Perceptions about Tuberculosis in Agropastoral Communities in Northern Tanzania: A Cross-Sectional Study

Aim: To determine knowledge and perceptions about tuberculosis in agropastoral communities in Northern Tanzania. Study Design: This was a cross sectional study on habits and attitudes to tuberculosis. Methods: The study was conducted between June 2011 and May 2012.We enrolled tuberculosis patients registered at Mount Meru Hospital in Arusha municipal, Enduleni Hospital in Ngorongoro district, and Haydom Lutheran Hospital in Mbulu district. In addition we selected for comparison some of their household relatives and individuals from the neighborhood. Data was collected using a structured questionnaire. Knowledge about tuberculosis was assessed by questions concerning causes, symptoms, modes of transmission and prevention and treatment. Key variables for assessment of perception on tuberculosis included: individuals considered most at risk, and misconceptions. Results: We recruited 164 respondents of whom 25% were confirmed tuberculosis patients, 41.5% relatives of the patients and 33.5% neighbors. Females constituted 48.8% of all respondents. Of all the participants, only two of the neighbors had never heard about tuberculosis in their life time. Even though 99% had heard about tuberculosis, specific knowledge on causes, prevention and treatment was poor. A total of 67.7% thought that transmission of tuberculosis occurs during sexual intercourse. Respondents thought that risk from tuberculosis was higher among adults (68.9%), alcohol users (39.6%), smoking (26.8%), consumption of raw animal products (6.1%) and childhood (23.2%). Conclusion: Our study shows that study participants had heard about tuberculosis but specific knowledge was low. Misconceptions surrounding causes, transmission, prevention and treatment of the disease were common. Selection of appropriate channels for public health education and awareness programmes targeting knowledge about prevention and control of tuberculosis in agropastoral communities may improve this situation.publishedVersio

Gene editing and agrifood systems

Gene-editing technologies represent a promising new tool for plant and animal breeding in low- and middle-income countries. They enhance precision and efficiency over current breeding methods and could lead to rapid development of improved plant varieties and animal breeds. However, as for any new technology, they have their merits and demerits. There is, as yet, no international consensus regarding if and how gene-edited organisms should be regulated, and whether their release would fall under the regulatory framework of the Cartagena Protocol on Biosafety to the Convention on Biological Diversity. This science- and evidence-based Issue Paper on gene editing and agrifood systems presents a balanced discussion of the most pertinent aspects of gene editing, including the consequences for human hunger, human health, food safety, effects on the environment, animal welfare, socioeconomic impact and distribution of benefits. Intrinsic ethical concerns and issues of governance and regulation are addressed, and the roles of the public and private sectors, alone and in partnership, are summarized. Various scenarios are also presented for how gene editing might be used in the future to help transform agrifood systems

Phase II study of preoperative bevacizumab, capecitabine and radiotherapy for resectable locally-advanced rectal cancer

Background: to evaluate whether the addition of bevacizumab (BVZ) to capecitabine-based chemoradiotherapy in the preoperative treatment of locally advanced rectal cancer (LARC) improves efficacy measured by the pathological complete response (pCR) rate. Methods: a phase II two-step design was performed. Patients received four cycles of therapy consisting of: BVZ 10 mg/kg in first infusion on day 1 and 5 mg/kg on days 15, 29, 43, capecitabine 1800 mg/m2/day 5 days per week during radiotherapy, which consisted of external-beam irradiation (45 Gy in 1.8 Gy dose per session over 5 sessions/week for 5 weeks). Six to eight weeks after completion of all therapies surgery was undergone. To profile the biological behaviour during BVZ treatment we measured molecular biomarkers before treatment, during BVZ monotherapy, and during and after combination therapy. Microvessel density (MVD) was measured after surgery. Results: forty-three patients were assessed and 41 were included in the study. Three patients achieved a pathological complete response (3/40: 7.5%) and 27 (67.5%) had a pathological partial response, (overall pathological response rate of 75%). A further 8 patients (20%) had stable disease, giving a disease control rate of 95%. Downstaging occurred in 31 (31/40: 77.5%) of the patients evaluated. This treatment resulted in an actuarial 4-year disease-free and overall survival of 85.4 and 92.7% respectively. BVZ with chemoradiotherapy showed acceptable toxicity. No correlations were observed between biomarker results and efficacy variables. Conclusion: BVZ with capecitabine and radiotherapy seem safe and active and produce promising survival results in LARC

Stripes in cuprate superconductors: Excitations and dynamic dichotomy

We present a short account of the present experimental situation of stripes in cuprates followed by a review of our present understanding of their ground state and excited state properties. Collective modes, the dynamical structure factor, and the optical conductivity of stripes are computed using the time-dependent Gutzwiller approximation applied to realistic one band and three band Hubbard models, and are found to be in excellent agreement with experiment. On the other hand, experiments like angle-resolved photoemission and scanning tunneling microscopy show the coexistence of stripes at high energies with Fermi liquid quasiparticles at low energies. We show that a phenomenological model going beyond mean-field can reconcile this dynamic dichotomy.Comment: 20 pages, 14 figures. Review paper for a Special Issue of Physica C on "Stripes and Electronic Liquid Crystals in Strongly Correlated Systems

Therapeutic effect of all-trans-retinoic acid (at-RA) on an autoimmune nephritis experimental model: role of the VLA-4 integrin

BACKGROUND: Mercuric chloride (HgCl(2)) induces an autoimmune nephritis in the Brown Norway (BN) rats characterized by anti-glomerular basement membrane antibodies (anti-GBM Ab) deposition, proteinuria and a severe interstitial nephritis, all evident at day 13 of the disease. We assessed the effects of all-trans retinoic acid (at-RA) in this experimental model. At-RA is a vitamin A metabolite which has shown beneficial effects on several nephropathies, even though no clear targets for at-RA were provided. METHODS: We separated animals in four different experimental groups (HgCl(2), HgCl(2)+at-RA, at-RA and vehicle). From each animal we collected, at days 0 and 13, numerous biological samples: urine, to measure proteinuria by colorimetry; blood to determine VLA-4 expression by flow citometry; renal tissue to study the expression of VCAM-1 by Western blot, the presence of cellular infiltrates by immunohistochemistry, the IgG deposition by immunofluorescence, and the cytokines expression by RT-PCR. Additionally, adhesion assays to VCAM-1 were performed using K562 α4 transfectant cells. ANOVA tests were used for statistical significance estimation. RESULTS: We found that at-RA significantly decreased the serum levels of anti-GBM and consequently its deposition along the glomerular membrane. At-RA markedly reduced proteinuria as well as the number of cellular infiltrates in the renal interstitium, the levels of TNF-α and IL-1β cytokines and VCAM-1 expression in renal tissue. Moreover, we reported here for the first time in an in vivo model that at-RA reduced, to basal levels, the expression of VLA-4 (α4β1) integrin induced by mercury on peripheral blood leukocytes (PBLs). In addition, using K562 α4 stable transfectant cells, we found that at-RA inhibited VLA-4 dependent cell adhesion to VCAM-1. CONCLUSION: Here we demonstrate a therapeutic effect of at-RA on an autoimmune experimental nephritis model in rats. We report a significant reduction of the VLA-4 integrin expression on PBLs as well as the inhibition of the VLA4/VCAM1-dependent leukocyte adhesion by at-RA treatment. Thereby we point out the VLA-4 integrin as a target for at-RA in vivo

The NEXT White (NEW) detector

Conceived to host 5 kg of xenon at a pressure of 15 bar in the fiducial volume, the NEXT-White apparatus is currently the largest high pressure xenon gas TPC using electroluminescent amplification in the world. It is also a 1:2 scale model of the NEXT-100 detector for Xe-136 beta beta 0 nu decay searches, scheduled to start operations in 2019. Both detectors measure the energy of the event using a plane of photomultipliers located behind a transparent cathode. They can also reconstruct the trajectories of charged tracks in the dense gas of the TPC with the help of a plane of silicon photomultipliers located behind the anode. A sophisticated gas system, common to both detectors, allows the high gas purity needed to guarantee a long electron lifetime. NEXT-White has been operating since October 2016 at the Laboratorio Subterraneo de Canfranc (LSC), in Spain. This paper describes the detector and associated infrastructures, as well as the main aspects of its initial operation