Evaluacion de la suceptibilidad a Maize Dwarf Mosaic Virus - MDMV de 318 lineas de maiz (Zea mays L).

50 p.Durante la temporada 2003-2004, se realizó un ensayo con 318 genotipos de maíz, destinado a evaluar su susceptibilidad y la eficiencia de la inoculación mecánica del virus del mosaico enanizante del maíz (Maize dwarf mosaic virus – MDMV). Este se llevó a cabo en condiciones de campo, analizando los índices de incidencia y severidad de los síntomas. Los parámetros a analizar fueron medidos a través del porcentaje de plantas infectadas respecto el total de plantas del tratamiento para incidencia y mediante una escala ordinal para severidad. Las 318 líneas presentaron síntomas característicos a los producidos por el patógeno, con niveles de incidencia y severidad en diferentes grados. Además se observó la eficiencia de la inoculación mecánica del virus y las distintas reacciones de las plantas por la presencia de MDMV.De acuerdo a los resultados obtenidos, tanto para los índices de incidencia como severidad, se separaron los genotipos en tres categorías, donde en la primera se agruparon aquellas líneas con mayor resistencia a la infección del patógeno. Aquí destacan dos genotipos, 10045 y 10046, los que manifestaron un menor número de plantas infectadas y una baja severidad de síntomas del virus del mosaico enanizante del maíz (Maize dwarf mosaic virus – MDMV)

Determinação numerica e experimental de coeficientes locais de transferencia de calor em difusões radiais

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro TecnologicoO estudo da transferência de calor em difusores radiais com alimentação axial, mostrou em trabalho recente a presença de grandes divergências entre resultados numéricos e experimentais. Aparentemente tais divergências estão associadas à presença de oscilações auto induzidas pelo escoamento, que aumentam a troca de calor entre o fluído e as paredes do difusor. Neste contexto o presente trabalho tem como objetivo detectar a presença de instabilidades no escoamento bem como suas localizações. Visando tal objetivo, mediu-se a transferência de calor local entre o fluído e parede do difusor, usando a técnica de sublimação de naftaleno. A quantidade de naftaleno sublimada foi medida ponto a ponto para diversas vazões no difusor. Comparando estes resultados com uma solução numérica em regime permanente, foi possível identificar as regiões instáveis. Observou-se para altos números de Reynolds, a presença de aumentos significativos na troca de calor no setor de saída do difusor. Tais aumentos deslocam-se na direção do centro do difusor com o aumento do número de Reynolds

La donazione di organi. Una domanda di salute tra efficienza di sistema e solidariet\ue0 individuale e collettiva

Questo articolo presenta una ricerca sulla donazione e trapianto di organo proveniente da paziente in morte encefalica, evidenziando le differenze tra contesti regionali e alcune realt\ue0 specifiche del territorio regionale ligure e formula alcune ipotesi esplicative delle differenze rilevate. Lo studio analizza il funzionamento del sistema su indicatori di processo e di risultato per tentare di comprendere e modellizzare il ruolo giocato dai contesti nello spiegare le differenze. Sono stati analizzati i dati provenienti dal sistema informativo per quantificare gli indicatori e interviste con testimoni qualificati per interpretare l\u2019evidenza emersa dai dati

Diabetes, intracranial stenosis and microemboli in asymptomatic carotid stenosis

Background: The risk of stroke in patients with asymptomatic carotid stenosis (ACS) is now so low that it is important to have methods to identify those patients most likely to benefit from intervention, or who may require special consideration in choice of medical therapy. We studied the prediction of stroke, death or transient ischemic attacks (stroke/death/TIA) in patients with ACS by intracranial arterial stenosis, and microemboli on transcranial Doppler (TCD), and the effect of diabetes mellitus on microemboli, intracranial stenosis and risk of events. Methods: Patients with ACS \u3e 60% by Doppler ultrasound were recruited from the Stroke Prevention Clinic of University Hospital, London, Canada. All 339 participants underwent TCD for detection of intracranial stenosis and detection of microemboli, and carotid ultrasound to measure extracranial stenosis and total carotid plaque area. Participants were followed for three years, to determine the risk of stroke/death/TIA. Results: Stroke/death/TIA occurred in 38% of patients with microemboli versus 10% without (p=0.0001), and in 18% of patients with intracranial stenosis, versus 10% without (p=0.042). Diabetics were significantly more likely to have intracranial stenosis (45% vs. 29%, p =0.014), microemboli (38% vs. 10%, p \u3c0.0001), and had significantly higher risk of stroke/death/TIA over three years (21% vs. 11% without; p=0.024). Survival free of stroke, TIA or death was significantly better without microemboli or intracranial stenosis (p\u3c0.0001). Conclusions: Diabetes, microemboli and intracranial stenosis predicted higher risk of stroke, death or TIA than did extracranial stenosis or total plaque area; diabetics may need more intensive therapy

Experimental artifact in MOKE measurements when using paramagnetic sample holders

We describe here an artifact that may affect to magneto-optical Kerr measurements. When paramagnetic sample holders (SH) with non-negligible susceptibilities are used, the inhomogeneity of the applied magnetic field can induce forces and torques on it, shifting the reflected beam, and altering its intensity at the photodetector. The effect is even and can be avoided using low susceptibility paramagnetic or diamagnetic SH We also present a detailed analytical description of the magnetic forces involved and provide some estimated values of the SH shifting, showing that they might distort the magneto-optical Kerr effect signal. Moreover, in this paper we show how the artifact can be removed from the experimental curves with an appropriated data analysis.Fil: Munoz-Noval, Alvaro. Comunidad de Madrid; EspañaFil: Bonin, Claudio Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Física del Litoral. Universidad Nacional del Litoral. Instituto de Física del Litoral; ArgentinaFil: Bonetto, Fernando Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Física del Litoral. Universidad Nacional del Litoral. Instituto de Física del Litoral; ArgentinaFil: Garcia, Miguel Angel. Institute For Ceramic And Glass; Españ

Easy Learning from Label Proportions

We consider the problem of Learning from Label Proportions (LLP), a weakly supervised classification setup where instances are grouped into "bags", and only the frequency of class labels at each bag is available. Albeit, the objective of the learner is to achieve low task loss at an individual instance level. Here we propose Easyllp: a flexible and simple-to-implement debiasing approach based on aggregate labels, which operates on arbitrary loss functions. Our technique allows us to accurately estimate the expected loss of an arbitrary model at an individual level. We showcase the flexibility of our approach by applying it to popular learning frameworks, like Empirical Risk Minimization (ERM) and Stochastic Gradient Descent (SGD) with provable guarantees on instance level performance. More concretely, we exhibit a variance reduction technique that makes the quality of LLP learning deteriorate only by a factor of k (k being bag size) in both ERM and SGD setups, as compared to full supervision. Finally, we validate our theoretical results on multiple datasets demonstrating our algorithm performs as well or better than previous LLP approaches in spite of its simplicity

Determinacion de la importancia de malezas solanaceas asociadas a vinedos como fuente de inoculo de ArMV yTomRSV.

34 p.Para determinar la importancia de malezas solanáceas (Datura Stramonium) asociadas a viñedos como fuente de inóculo de ArMV y TomRSV se realizó entre los meses de Marzo y Mayo del 2003 un muestreo en forma dirigida hacia malezas solanáceas que presentaban síntomas de virosis y a plantas de vid que se encontraban cercanas a malezas con sintomatología viral. Se prospectaron 2 viñedos ubicados en Talca precisamente en la comuna de San Clemente, colectando un total de 42 muestras las cuales fueron sometidas a la técnica sexológica DAS-ELISA para determinar la presencia de ArMV y TomRSV. Los porcentajes de infección fueron de 73,7 y 69,6% para un predio y otro encontrándose solo en un huerto la presencia de ambos virus. También se realizó un estudio paralelo destinado a la determinación de la existencia de nemátodos del género Xiphinema SP a través del método del embudo de Baermann. Esto con la finalidad de asociar estos organismos a la presencia de los nepovirus en estudio

Association of homocysteine and smoking with cerebral microemboli in patients with mechanical heart valves: A transcranial Doppler study

Objectives Microembolic signals (MES) on transcranial Doppler (TCD) predict stroke and cognitive decline. Plasma levels of total homocysteine (tHcy), a prothrombotic factor, are higher in patients with microemboli in carotid stenosis and in patients with paradoxical embolism. In this study we assessed the association between the level of tHcy and the number of MES in patients with mechanical heart valves (MHVs). Methods TCD monitoring was performed to detect MES before and after breathing 100% oxygen and repeated every 2-4 weeks up to six times. Results Twenty-five patients with MHVs (mean age: 63.60±10.15 years) participated in this study; 15 were men (66.47±7.25 years) and 10 were women (59.30±12.60 years). In total, there were 126 study visits. In multiple regression, higher tHcy was associated with more MES in both preoxygenation (OR 1.34 (95% CI 1.07 to 1.68, P=0.009)) and postoxygenation (OR 1.40 (95% CI 1.07 to 1.83, P=0.01)) phases. Current smoking and the length of time between the operation and monitoring also correlated with a higher number of MES before and after breathing oxygen, particularly in women. Conclusions Higher tHcy and smoking were associated with a higher MES count in both preoxygenation and postoxygenation phases. Because smoking can be stopped and hyperhomocysteinaemia is treatable, these are clinically important findings