Core-level photoemission spectroscopy of nitrogen bonding in GaNxAs1–x alloys

The nitrogen bonding configurations in GaNxAs1–x alloys grown by molecular beam epitaxy with 0.07=0.03, the nitrogen is found to exist in a single bonding configuration – the Ga–N bond; no interstitial nitrogen complexes are present. The amount of nitrogen in the alloys is estimated from the XPS using the N 1s photoelectron and Ga LMM Auger lines and is found to be in agreement with the composition determined by x-ray diffraction

Asignación forrajera y consumo de nutrientes de Panicum coloratum L. por ovinos en pastoreo

El objetivo del presenta estudio fue determinar el consumo de nutrientes en Panicum coloratum L. cv Verde, a diferentes niveles de asignación forrajera (AF) bajo condiciones del diferimiento del forraje producido desde fines de febrero. La cuantificación de la selección de nutrientes permitiría determinar el grado de utilización de la pastura y/o cantidad de forraje a suministrar, y el tipo y calidad de suplemento requerido para cubrir deficiencias. El presente estudio se realizó en las instalaciones de la Facultad de Agronomía (UNLPam) durante junio-julio de 1994. En el mismo se establecieron cuatro niveles de asignación forrajera (15, 30, 45, 60 g MS kg PV-1.dia-1) sin repeticiones, por modificación del área de la pastura y rotación diaria de los animales. Se emplearon seis ovinos machos sin castrar raza Pampinta (peso inicial 52,9 ± 4,3 Kg.) por tratamiento, de los cuales cinco estaban provistos con bolsas recolectoras de heces. Se estimó la forrajimasa en pre-pastoreo (Fpre) a partir de tres cortes a nivel del suelo. Para determinar la forrajimasa residual (post-pastoreo: Fpost) se realizaron tres mediciones apareadas a las anteriores. El consumo de materia seca (CM S) se calculó por diferencia entre valores de Fpre y Fpost. Se determinó proteína Bruta (PB), digestibilidad in vitro de la materia seca (DIVMS) y fibra detergente neutro (FDN) sobre muestras compuestas pertenecientes a Fpre y Fpost. La concentración de un nutriente seleccionado (Nsel, g Kg-I MS) por los ovinos se calculó como: Nsel = ((Fpre x Npre) - (Fpost x Npost»/(Fpre - Fpost), donde Fpre y Fpost (en g MS.m2), y Npre y Npost (g kg-1 Ms) son la forrajimasa y concentración de un nutriente en pre y postpastoreo (Nsel:Npre). El efecto de la AF sobre CMS, producción de heces y relación Nsel:Npre se analizó por regresión lineal. El CMS aumentó (p < 0,01) linealmente, con AF, desde 25 a 70 g MS/Kg PV 0.75. La Fpost aumentó (p < 0,01) desde 35 a 101 g MS/ m2 al igual que la producción de heces (p < 0,01) de 6,9 a 11,8 g MS/Kg PV. DIVMSsel y PBsel aumentaron (p < 0,05) desde un 4 a 17% Y 18 a 45% sobre el valor en prepastoreo, respectivamente. FDNsel diminuyó (p < 0,01) linealmente desde 4 a 15%. Los resultados muestran que el consumo de MS incrementó (p < 0,01) linealmente hasta la asignación de 60 g MS/Kg PV.dia. Esto indicaría que la asignación, a este nivel, aún restringe el consumo en ovinos.Director: Ing. Agr. Carlos M. FerriCo-director: Ing. Agr. Nestor Stritzle

Novel models to predict elevated intracranial pressure during intensive care and long-term neurological outcome after TBI

status: publishe

Photoluminescence spectroscopy of bandgap reduction in dilute InNAs alloys

Photoluminescence (PL) has been observed from dilute InNxAs1–x epilayers grown by molecular-beam epitaxy. The PL spectra unambiguously show band gap reduction with increasing N content. The variation of the PL spectra with temperature is indicative of carrier detrapping from localized to extended states as the temperature is increased. The redshift of the free exciton PL peak with increasing N content and temperature is reproduced by the band anticrossing model, implemented via a (5×5) k·p Hamiltonian

Band anticrossing in GaNxSb1–x

Fourier transform infrared absorption measurements are presented from the dilute nitride semiconductor GaNSb with nitrogen incorporations between 0.2% and 1.0%. The divergence of transitions from the valence band to E– and E+ can be seen with increasing nitrogen incorporation, consistent with theoretical predictions. The GaNSb band structure has been modeled using a five-band k·p Hamiltonian and a band anticrossing fitting has been obtained using a nitrogen level of 0.78 eV above the valence band maximum and a coupling parameter of 2.6 eV

The gravitational wave rocket

Einstein's equations admit solutions corresponding to photon rockets. In these a massive particle recoils because of the anisotropic emission of photons. In this paper we ask whether rocket motion can be powered only by the emission of gravitational waves. We use the double series approximation method and show that this is possible. A loss of mass and gain in momentum arise in the second approximation because of the emission of quadrupole and octupole waves.Comment: 10 pages LaTe

Thematic Trends in Complementary and Alternative Medicine Applied in Cancer-Related Symptoms

Purpose: The main goal of this study is to discover the scientific evolution of Cancer-Related Symptoms in Complementary and Alternative Medicine research area, analyzing the articles indexed in the Web of Science database from 1980 to 2013. Design/Methodology/Approach: A co-word science mapping analysis is performed under a longitudinal framework (1980 to 2013). The documental corpus is divided into two subperiods, 1980–2008 and 2009–2013. Thus, the performance and impact rates, and conceptual evolution of the research field are shown. Findings: According to the results, the co-word analysis allows us to identify 12 main thematic areas in this emerging research field: anxiety, survivors and palliative care, meditation, treatment, symptoms and cancer types, postmenopause, cancer pain, low back pain, herbal medicine, children, depression and insomnia, inflammation mediators, and lymphedema. The different research lines are identified according to the main thematic areas, centered fundamentally on anxiety and suffering prevention. The scientific community can use this information to identify where the interest is focused and make decisions in different ways. Research limitation: Several limitations can be addressed: 1) some of the Complementary and Alternative Medicine therapies may not have been included; 2) only the documents indexed in Web of Science are analyzed; and 3) the thematic areas detected could change if another dataset was considered. Practical implications: The results obtained in the present study could be considered as an evidence-based framework in which future studies could be built. Originality/value: Currently, there are no studies that show the thematic evolution of this research area

TEAD and YAP regulate the enhancer network of human embryonic pancreatic progenitors.

The genomic regulatory programmes that underlie human organogenesis are poorly understood. Pancreas development, in particular, has pivotal implications for pancreatic regeneration, cancer and diabetes. We have now characterized the regulatory landscape of embryonic multipotent progenitor cells that give rise to all pancreatic epithelial lineages. Using human embryonic pancreas and embryonic-stem-cell-derived progenitors we identify stage-specific transcripts and associated enhancers, many of which are co-occupied by transcription factors that are essential for pancreas development. We further show that TEAD1, a Hippo signalling effector, is an integral component of the transcription factor combinatorial code of pancreatic progenitor enhancers. TEAD and its coactivator YAP activate key pancreatic signalling mediators and transcription factors, and regulate the expansion of pancreatic progenitors. This work therefore uncovers a central role for TEAD and YAP as signal-responsive regulators of multipotent pancreatic progenitors, and provides a resource for the study of embryonic development of the human pancreas