ALTERATIONS IN HYPOTHALAMIC CONTENT OF LUTEINIZING HORMONE RELEASING HORMONE AND PITUITARY RESPONSIVENESS ASSOCIATED WITH TESTICULAR REGRESSION INDUCED BY PINEAL RELATED TREATMENTS IN THE GOLDEN HAMSTER

The adult male golden hamster, when exposed to blinding (BL), short photoperiod (SP), or daily melatonin injections (MEL) demonstrates dramatic reproductive collapse. This collapse can be blocked by removal of the pineal gland prior to treatment. Reproductive collapse is characterized by a dramatic decrease in both testicular weight and serum gonadotropin titers. The present study was designed to examine the interactions of the hypothalamus and pituitary gland during testicular regression, and to specifically compare and contrast changes caused by the three commonly employed methods of inducing testicular regression (BL,SP,MEL). Hypothalamic LHRH content was altered by all three treatments. There was an initial increase in content of LHRH that occurred concomitantly with the decreased serum gonadotropin titers, followed by a precipitous decline in LHRH content which reflected the rapid increases in both serum LH and FSH which occur during spontaneous testicular recrudescence. In vitro pituitary responsiveness was altered by all three treatments: there was a decline in basal and maximally stimulatable release of both LH and FSH which paralleled the fall of serum gonadotropins. During recrudescence both basal and maximal release dramatically increased in a manner comparable to serum hormone levels. While all three treatments were equally effective in their ability to induce changes at all levels of the endocrine system, there were important temporal differences in the effects of the various treatments. Melatonin injections induced the most rapid changes in endocrine parameters, followed by exposure to short photoperiod. Blinding required the most time to induce the same changes. This study has demonstrated that pineal-mediated testicular regression is a process which involves dynamic changes in multiply-dependent endocrine relationships, and proper evaluation of these changes must be performed with specific temporal events in mind. ^

Ludwig Lewisohn: The Golden Vase ... [Rezension]

P. A.

The golden ship and other tales : translated from the Swahili

[Gertrude Ward]. With illustrations by Lilian Bell & Alice B. Woodward

Performance of Gibson Golden Delicious on Dwarfing Rootstocks

To evaluate the adaptability and performance of new and promising apple rootstocks in the dwarfing size-control category, a NC-140 regional rootstock trial was established in 2003 at 14 sites in the United States (AR, CA, IA, GA, KY, ME, MI, NY, OH, PA, UT, WI), Canada (BC), and Mexico. The Iowa planting, located at the ISU Horticulture Research Station, includes 23 rootstocks with new selections from the Cornell-Geneva breeding program (G, CG), Russia (Bud), Czech Republic (J-TE), Japan (JM), and Germany (PiAu) with M.26, M.9 Pajam 2, and M.9 T337 serving as industry standards. These rootstocks are being evaluated with Gibson Golden Delicious serving as the test cultivar. This report summarizes the tree-growth and production characteristics through the 2011 growing season.

The Spanish Ballad in the Golden Age, de Nigel Griffin, Clive Griffin, Eric Southworth y Colin Thompson (eds.)

Fil: Di Croce, Ely V.. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

The Spanish Ballad in the Golden Age, de Nigel Griffin, Clive Griffin, Eric Southworth y Colin Thompson (eds.)

Fil: Di Croce, Ely V.. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

The Spanish Ballad in the Golden Age, de Nigel Griffin, Clive Griffin, Eric Southworth y Colin Thompson (eds.)

Fil: Di Croce, Ely V.. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

(Table S1) Flux gate discharge and centerline discharge of Helheim, Kangerdlugssuaq and Jakobshavn glacier, Greenland

Acceleration of Greenland's three largest outlet glaciers, Helheim, Kangerdlugssuaq and Jakobshavn Isbræ, accounted for a substantial portion of the ice sheet's mass loss over the past decade. Rapid changes in their discharge, however, make their cumulative mass-change uncertain. We derive monthly mass balance rates and cumulative balance from discharge and surface mass balance (SMB) rates for these glaciers from 2000 through 2010. Despite the dramatic changes observed at Helheim, the glacier gained mass over the period, due primarily to the short duration of acceleration and a likely longer-term positive balance. In contrast, Jakobshavn Isbræ lost an equivalent of over 11 times the average annual SMB and loss continues to accelerate. Kangerdlugssuaq lost over 7 times its annual average SMB, but loss has returned to the 2000 rate. These differences point to contrasts in the long-term evolution of these glaciers and the danger in basing predictions on extrapolations of recent changes.

Thermal effects in Ni/Au and Mo/Au gate metallization AlGaN/GaN HEMT's reliability

AlGaN/GaN high electron mobility transistors (HEMT) are key devices for the next generation of high-power, high-frequency and high-temperature electronics applications. Although significant progress has been recently achieved [1], stability and reliability are still some of the main issues under investigation, particularly at high temperatures [2-3]. Taking into account that the gate contact metallization is one of the weakest points in AlGaN/GaN HEMTs, the reliability of Ni, Mo, Pt and refractory metal gates is crucial [4-6]. This work has been focused on the thermal stress and reliability assessment of AlGaN/GaN HEMTs. After an unbiased storage at 350 o C for 2000 hours, devices with Ni/Au gates exhibited detrimental IDS-VDS degradation in pulsed mode. In contrast, devices with Mo/Au gates showed no degradation after similar storage conditions. Further capacitance-voltage characterization as a function of temperature and frequency revealed two distinct trap-related effects in both kinds of devices. At low frequency (< 1MHz), increased capacitance near the threshold voltage was present at high temperatures and more pronounced for the Ni/Au gate HEMT and as the frequency is lower. Such an anomalous “bump” has been previously related to H-related surface polar charges [7]. This anomalous behavior in the C-V characteristics was also observed in Mo/Au gate HEMTs after 1000 h at a calculated channel temperatures of around from 250 o C (T2) up to 320 ºC (T4), under a DC bias (VDS= 25 V, IDS= 420 mA/mm) (DC-life test). The devices showed a higher “bump” as the channel temperature is higher (Fig. 1). At 1 MHz, the higher C-V curve slope of the Ni/Au gated HEMTs indicated higher trap density than Mo/Au metallization (Fig. 2). These results highlight that temperature is an acceleration factor in the device degradation, in good agreement with [3]. Interface state density analysis is being performed in order to estimate the trap density and activation energy.

Daños mecánicos en manzana «Golden»

El sector nacional de frutos de pepita debe incrementar sus esfuerzos por mejorar la calidad de la fruta en lo relativo a los daños mecánicos, según concluye este estudio realizado en 72 comercios minoristas de Madrid.

Daños mecánicos en frutos de manzanas del cv. "Golden Delicious" tratadas con calcio.

Se han realizado tres ensayos con manzanas del cv. "Golden Delicious" procedentes de Lérida que diferían en sus tratamientos de calcio, siempre manteniendo un testigo sin tratar. En un primer ensayo se comparan manzanas tratadas con no tratadas; en el segundo se comparan manzanas tratadas en pre y post cosecha y en un tercero se comparan tratamientos en precosecha con CaCl2 y quelatos. Todos los frutos han sido sometidos a ensayos de impacto, corte y penetración. Se discute la posibilidad de que estos tratamientos mejoren la resistencia a los daños y la calidad.

Bit noise from an optical logic gate with laser diodes

Output bits from an optical logic cell present noise due to the type of technique used to obtain the Boolean functions of two input data bits. We have simulated the behavior of an optically programmable logic cell working with Fabry Perot-laser diodes of the same type employed in optical communications (1550nm) but working here as amplifiers. We will report in this paper a study of the bit noise generated from the optical non-linearity process allowing the Boolean function operation of two optical input data signals. Two types of optical logic cells will be analyzed. Firstly, a classical "on-off" behavior, with transmission operation of LD amplifier and, secondly, a more complicated configuration with two LD amplifiers, one working on transmission and the other one in reflection mode. This last configuration has nonlinear behavior emulating SEED-like properties. In both cases, depending on the value of a "1" input data signals to be processed, a different logic function can be obtained. Also a CW signal, known as control signal, may be apply to fix the type of logic function. The signal to noise ratio will be analyzed for different parameters, as wavelength signals and the hysteresis cycles regions associated to the device, in relation with the signals power level applied. With this study we will try to obtain a better understanding of the possible effects present on an optical logic gate with Laser Diodes.

Influencia del riego en precosecha sobre la calidad de manzanas Golden Supreme y Golden Smoothee.

El riego, práctica habitual y a la vez indispensable de nuestra fruticultura constituye, en su manejo, uno de los principales factores determinantes de la producción y calidad final del fruto, y sobre el cual el agricultor desempeña un papel indispensable como regulador. A este respecto hay varios estudios que entre si presentan conclusiones dispares. El hecho de aumentar la frecuencia y dosis de riego provoca, según varios autores, una disminución en la firmeza de las manzanas (Asaf et al., 1975), mientras que en otras investigaciones se observa el fenómeno contrario (Reichel y Schmidt, 1983). También hay estudios con resultados dispares en relación al efecto que el riego pueda tener en la acidez titulable y el contenido en sólidos solubles del fruto. No obstante, parece ser que una restricción de riego en precosecha se traduce en un aumento de los sólidos solubles de los frutos (Ramos et al., 1993) y en una disminución de su acidez (Recasens et al., 1988). La fecha de recolección también es un factor muy importante en vistas a una optimización tanto de rendimientos de la plantación como de la aptitud del fruto para su frigoconservación. Recolectar un mismo fruto una semana más tarde implica una pérdida de firmeza durante su frigoconservación de aproximadamente 1,5 N por mes, pasando de unas pérdidas mensuales de 3 N a 4,5 N según se haga la recolección en el momento optimo o después (Duran, 1990). Es este acumulo de discrepancias el que ha motivado el planteamiento de este ensayo para nuestras propias condiciones de cultivo. En él se pretende ver si diferentes fechas de recolección y condiciones de riego pueden influir en la firmeza de los frutos y por tanto en su sensibilidad a la manipulación, aspecto de gran interés en el momento de la cosecha. Asimismo es preciso comprobar que estas prácticas culturales no afecten a la calidad del fruto.