Laser-chemical vapor deposition of W Schottky contacts on GaAs\ud using WF6 and SiH4

Reports on the deposition of tungsten on gallium arsenide (GaAs) using a low-temperature laser-chemical vapor deposition process. Induction of metallic W formation from a gas mixture; Columnar structure shown by scanning electron microscopy of the W films; Schottky diodes obtained during a laser based resistless projection patterning process on GaAs

Influence of cracks on the soil-atmosphere interaction: numerical coupled model of thermo- atmosphereporous media

Soil shrinks as it desiccates, and the magnitude of shrinkage can be large for clayey soils. The drying of soil leads to cracks formation, causing high suctions to develop within. Cracks expose the deep soil and more evaporation can be expected in dry periods. To illustrate the effect of cracking, a numerical model of soil-atmosphere interaction has been developed taking into account the thermo-fluid coupling of an unsaturated clay soil. The model is used to simulate the evolution of evaporation during the drying process. The main results show a significant influence of the presence of cracks on the evaporation. This study also offers a simple method for taking into account the presence of cracks in the soil-atmosphere exchange

Unilateral vs. bilateral STN DBS effects on working memory and motor function in Parkinson disease

Bilateral subthalamic nucleus deep brain stimulation (STN DBS) can reduce working memory while improving motor function in Parkinson disease (PD), but findings are variable. One possible explanation for this variability is that the effects of bilateral STN DBS on working memory function depend in part on functional or disease asymmetry. The goal of this study was to determine the relative contributions of unilateral DBS to the effects seen with bilateral DBS. Motor (Unified Parkinson Disease Rating Scale Part III, UPDRS) and working memory function (Spatial Delayed Response, SDR) were measured in 49 PD patients with bilateral STN DBS while stimulators were Both-off, Left-on, Right-on and Both-on in a randomized, double-blind manner. Patients were off PD medications overnight. Effects of unilateral DBS were compared to effects of bilateral STN DBS. Mean UPDRS and SDR responses to Left-on vs. Right-on conditions did not differ (p>.20). However, improvement in contralateral UPDRS was greater and SDR performance was more impaired by unilateral DBS in the more affected side of the brain than in the less affected side of the brain (p=.008). The effect of unilateral DBS on the more affected side on contralateral UPDRS and SDR responses was equivalent to that of bilateral DBS. These results suggest that motor and working memory function respond to unilateral STN DBS differentially depending on the asymmetry of motor symptoms

Fabrication and subband gap optical properties of silicon supersaturated with chalcogens by ion implantation and pulsed laser melting

Topographically flat, single crystal silicon supersaturated with the chalcogens S, Se, and Te was prepared by ion implantation followed by pulsed laser melting and rapid solidification. The influences of the number of laser shots on the atomic and carrier concentration-depth profiles were measured with secondary ion mass spectrometry and spreading resistance profiling, respectively. We found good agreement between the atomic concentration-depth profiles obtained from experiments and a one-dimensional model for plane-front melting, solidification, liquid-phase diffusion, with kinetic solute trapping, and surface evaporation. Broadband subband gap absorption is exhibited by all dopants over a wavelength range from 1 to 2.5 microns. The absorption did not change appreciably with increasing number of laser shots, despite a measurable loss of chalcogen and of electronic carriers after each shot.One of the authors M.T. acknowledges the financial support of the Fulbright Program. This research was supported in part by the U.S. Army ARDEC under Contract No. W15QKN-07- P-0092

Effects of Fusarium graminearum and Fusarium poae on disease parameters, grain quality and mycotoxin contamination in barley (part II)

BACKGROUND: Barley is one of the most important winter crops in the world, with multiple uses such as human consumption, animal feed and for the malting industry. This crop is affected by different diseases, such as Fusarium Head Blight (FHB), that causes losses in yield and quality. In the last years F. graminearum and F. poae were two of the most frequently isolated species in barley grains, so the aim of this study was to evaluate the interaction between these Fusarium species and the effects on disease parameters, grain quality and mycotoxin contamination on five barley genotypes under field conditions. RESULTS: Statistical differences between Fusarium treatments for some parameters depending mainly on the year/genotype were found. The results showed that germination process was affected by both Fusarium species. As to grain quality and the different hordein fractions, it was observed that F. graminearum affects preferentially D and C hordeins Different concentrations of nivalenol, deoxynivalenol and their acetylated derivatives (3-ADON and 15-ADON) were detected. CONCLUSIONS: In the present work, no evidence of synergism between F. graminearum and F. poae were found regarding disease parameters and mycotoxin contamination. However, at least in the years with favorable climatic conditions to FHB development and depending on the barley genotype, a continuous monitoring is deemed necessary to prevent the negative impact on protein composition and germinative parametersFil: Martínez, Mauro. Universidad Nacional del Centro de la Provincia de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Cientifico Tecnolológico Mar del Plata. Instituto de Investigaciones en Biodiversidad y Biotecnología. Laboratorio de Biología Funcional y Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Biodiversidad y Biotecnología; ArgentinaFil: Ramirez Albuquerque, Lady Diana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; ArgentinaFil: Dinolfo, María Inés. Universidad Nacional del Centro de la Provincia de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Cientifico Tecnolológico Mar del Plata. Instituto de Investigaciones en Biodiversidad y Biotecnología. Laboratorio de Biología Funcional y Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Biodiversidad y Biotecnología; ArgentinaFil: Biganzoli, Fernando. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Métodos Cuantitativos y Sistemas de Información; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Fernández Pinto, Virginia Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; ArgentinaFil: Stenglein, Sebastian Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Cientifico Tecnolológico Mar del Plata. Instituto de Investigaciones en Biodiversidad y Biotecnología. Laboratorio de Biología Funcional y Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Biodiversidad y Biotecnología; Argentin

TOB is an effector of the hippocampus-mediated acute stress response

Stress affects behavior and involves critical dynamic changes at multiple levels ranging from molecular pathways to neural circuits and behavior. Abnormalities at any of these levels lead to decreased stress resilience and pathological behavior. However, temporal modulation of molecular pathways underlying stress response remains poorly understood. Transducer of ErbB2.1, known as TOB, is involved in different physiological functions, including cellular stress and immediate response to stimulation. In this study, we investigated the role of TOB in psychological stress machinery at molecular, neural circuit, and behavioral levels. Interestingly, TOB protein levels increased after mice were exposed to acute stress. At the neural circuit level, functional magnetic resonance imaging (fMRI) suggested that intra-hippocampal and hippocampal-prefrontal connectivity were dysregulated in Tob knockout (Tob-KO) mice. Electrophysiological recordings in hippocampal slices showed increased postsynaptic AMPAR-mediated neurotransmission, accompanied by decreased GABA neurotransmission and subsequently altered Excitatory/Inhibitory balance after Tob deletion. At the behavioral level, Tob-KO mice show abnormal, hippocampus-dependent, contextual fear conditioning and extinction, and depression-like behaviors. On the other hand, increased anxiety observed in Tob-KO mice is hippocampus-independent. At the molecular level, we observed changes in factors involved in stress response like decreased stress-induced LCN2 expression and ERK phosphorylation, as well as increased MKP-1 expression. This study introduces TOB as an important modulator in the hippocampal stress signaling machinery. In summary, we reveal a molecular pathway and neural circuit mechanism by which Tob deletion contributes to expression of pathological stress-related behavior

Pregnancy in multiple system atrophy: a case report

<p>Abstract</p> <p>Introduction</p> <p>Multiple system atrophy is a late, adult-onset α-synucleinopathy with no data on the effect of pregnancy on the disease course. Early stage multiple system atrophy can be difficult to distinguish from Parkinson's disease.</p> <p>Case presentation</p> <p>We describe the case of an Irish woman with parkinsonism starting at age 31, initially diagnosed as having dopa-responsive, idiopathic Parkinson's disease, who successfully delivered a full-term child at age 35. Her pregnancy was complicated by severe orthostatic hypotension and motor fluctuations. Two years post-partum, she underwent bilateral subthalamic nuclei deep brain stimulation for intractable motor fluctuations and disabling dyskinesia. After this treatment course she experienced deterioration of motor symptoms and death eight years after disease onset. Post-mortem neuropathological examination revealed striatonigral degeneration and α-synuclein-positive glial cytoplasmic inclusions in brain stem nuclei, basal ganglia and white matter tracts, consistent with a neuropathological diagnosis of multiple system atrophy.</p> <p>Conclusions</p> <p>Multiple system atrophy can affect women of child-bearing age and pregnancy may be associated with marked disease progression.</p

Emergence of Very Broad Infrared Absorption Band by Hyperdoping of Silicon with Chalcogens

We report the near through mid-infrared (MIR) optical absorption spectra, over the range 0.05–1.3 eV, of monocrystalline silicon layers hyperdoped with chalcogen atoms synthesized by ion implantation followed by pulsed laser melting. A broad mid-infrared optical absorption band emerges, peaking near 0.5 eV for sulfur and selenium and 0.3 eV for tellurium hyperdoped samples. Its strength and width increase with impurity concentration. Its strength decreases markedly with subsequent thermal annealing. The emergence of a broad MIR absorption band is consistent with the formation of an impurity band from isolated deep donor levels as the concentration of chalcogen atoms in metastable local configurations increases.Engineering and Applied Science