RHESSI and SOHO/CDS Observations of Explosive Chromospheric Evaporation

Simultaneous observations of explosive chromospheric evaporation are presented using data from the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and the Coronal Diagnostic Spectrometer (CDS) onboard SOHO. For the first time, co-spatial imaging and spectroscopy have been used to observe explosive evaporation within a hard X-ray emitting region. RHESSI X-ray images and spectra were used to determine the flux of non-thermal electrons accelerated during the impulsive phase of an M2.2 flare. Assuming a thick-target model, the injected electron spectrum was found to have a spectral index of ~7.3, a low energy cut-off of ~20 keV, and a resulting flux of >4x10^10 ergs cm^-2 s^-1. The dynamic response of the atmosphere was determined using CDS spectra, finding a mean upflow velocity of 230+/-38 km s^-1 in Fe XIX (592.23A), and associated downflows of 36+/-16 km s^-1 and 43+/-22 km s^-1 at chromospheric and transition region temperatures, respectively, relative to an averaged quiet-Sun spectra. The errors represent a 1 sigma dispersion. The properties of the accelerated electron spectrum and the corresponding evaporative velocities were found to be consistent with the predictions of theory.Comment: 5 pages, 4 figures, ApJL (In Press

The nature of the long time decay at a second order transition point

We show that at a second order phase transition, of \phi^4 like system, a necessary condition for streched exponential decay of the time structure factor is obeyed. Using the ideas presented in this proof a crude estimate of the decay of the structure factor is obtained and shown to yield stretched exponential decay under very reasonable conditions.Comment: 7 page

Golabi-Ito-Hall syndrome results from a missense mutation in the WW domain of the PQBP1 gene

Background: Golabi, Ito, and Hall reported a family with X linked mental retardation (XLMR), microcephaly, postnatal growth deficiency, and other anomalies, including atrial septal defect, in 1984.Methods: This family was restudied as part of our ongoing study of XLMR, but significant linkage to X chromosome markers could not be found. Extreme short stature and microcephaly as well as other new clinical findings were observed. Mutations in the polyglutamine tract binding protein 1 gene (PQBP1) have recently been reported in four XLMR disorders (Renpenning, Hamel cerebro-palato-cardiac, Sutherland-Haan, and Porteous syndromes) as well as in several other families. The clinical similarity of our family to these patients with mutations in PQBP1, particularly the presence of microcephaly, short stature, and atrial septal defect, prompted examination of this gene.Results: A missense mutation in PQBP1 was identified which changed the conserved tyrosine residue in the WW domain at position 65 to a cysteine (p.Y65C).Conclusions: This is the first missense mutation identified in PQBP1 and the first mutation in the WW domain of the gene. The WW domain has been shown to play an important role in the regulation of transcription by interacting with the PPxY motif found in transcription factors. The p.Y65C mutation may affect the proper functioning of the PQBP1 protein as a transcriptional co-activator

White mold

White mold, caused by the fungus Sclerotinia (Whetzelinia) sclerotiorum, is distributed worldwide and has more than 300 hosts. It infects flowers, cotyledons, seeds, leaves, or injured plant tissue. The disease can be controlled by crop rotation, flooding, reduced seeding rates, fewer irrigations, and destruction of bean- cull screenings containing sclerotia. Other control measures include chemical products in the middle of the flowering period, modifying plant architecture, and using resistant var. Many soil microorganisms are associated with sclerotia and may cause them to degrade or fail to germinate. The symptoms and damage caused by the disease are illustrated in color. (CIAT)El moho blanco causado por el hongo Sclerotinia (Whetzelinia) sclerotiorum se halla presente en todo el mundo, con mas de 300 plantas hospedantes del patogeno; infecta las flores, cotiledones, semillas, hojas o tejido lesionado. El control de la enfermedad se puede hacer por rotacion de cultivos, inundacion del terreno, menos riego y destruccion de residuos con esclerocios y utilizacion de menor cantidad de semilla en la siembra. Otras medidas de control incluyen la aplicacion de productos quimicos a mediados de la floracion, la modificacion de la arquitectura de la planta y la utilizacion de var. resistentes. Muchos microorganismos del suelo se asocian con los esclerocios y pueden causar degradacion e impedir que estos germinen. Se ilustran a color los sintomas y danos causados por la enfermedad. (CIAT

El moho blanco

White mold, caused by the fungus Sclerotinia (Whetzelinia) sclerotiorum, is distributed worldwide and has more than 300 hosts. It infects flowers, cotyledons, seeds, leaves or injured plant tissue. The disease can be controlled by crop rotation, flooding, reduced seeding rates, application of chemical products in the middle of the flowering period, modifying plant architecture and the use of resistant var. Many soil microorganisms are associated with sclerotia and may cause them to degrade or fan to germinate. The symptoms and damage caused by the disease are illustrated in color. (CIAT)El moho blanco causado por el hongo Sclerotinia (Whetzelinia) sclerotiorum se halla presente en todo el mundo y mas de 300 plantas son hospedantes del patogeno; infecta las flores, cotiledones, semillas, hojas o tejido herido. El control de la enfermedad se puede hacer por: rotacion de cultivos, inundacion del terreno, utilizacion de menor cantidad de semilla en la siembra, aplicacion de productos quimicos a mediados de la floracion, modificando la arquitectura de la planta y utilizando var resistentes; muchos microorganismos del suelo estan asociados con los esclerosios y pueden causar degradacion e impedir que estos germinen. Se ilustran en color los sintomas y danos causados por la enfermedad. (CIAT

An interval logic for higher-level temporal reasoning

Prior work explored temporal logics, based on classical modal logics, as a framework for specifying and reasoning about concurrent programs, distributed systems, and communications protocols, and reported on efforts using temporal reasoning primitives to express very high level abstract requirements that a program or system is to satisfy. Based on experience with those primitives, this report describes an Interval Logic that is more suitable for expressing such higher level temporal properties. The report provides a formal semantics for the Interval Logic, and several examples of its use. A description of decision procedures for the logic is also included

A volumetric Penrose inequality for conformally flat manifolds

We consider asymptotically flat Riemannian manifolds with nonnegative scalar curvature that are conformal to $\R^{n}\setminus \Omega, n\ge 3$, and so that their boundary is a minimal hypersurface. (Here, $\Omega\subset \R^{n}$ is open bounded with smooth mean-convex boundary.) We prove that the ADM mass of any such manifold is bounded below by $(V/\beta_{n})^{(n-2)/n}$, where $V$ is the Euclidean volume of $\Omega$ and $\beta_{n}$ is the volume of the Euclidean unit $n$-ball. This gives a partial proof to a conjecture of Bray and Iga \cite{brayiga}. Surprisingly, we do not require the boundary to be outermost.Comment: 7 page

Measurements of Carrier Generation-Recombination Parameters in Silicon Solar Cell Material Using MOS Techniques

Modified and new measurement techniques were developed for determining the carrier generation-recombination (G-R) parameters in silicon solar cell material under carrier deficit and low-level carrier excess conditions using MOS-based test structures. The structures mainly consisted of ring-dot MOS Capacitors (MOS-C) and Schottky-Drained Gate-Controlled Diodes (SGCD). Sample G-R parameters were extracted from n-type high quality silicon solar cell material. Additional measurements were also performed on low-quality ntype silicon substrates for comparison purposes. The photoaccelerated MOS-C Capacitance-time (C-t) transient measurement technique, modified from the standard C-t method, allows one to drastically reduce the observation time in deducing the carrier generation lifetime (Tg) by simply illuminating the test structure during the transient. In applying the technique to MOS-C’s (which exhibited generation lifetime on the order of I msec) the observation time was reduced by approximately an order of magnitude. This is important in dealing with solar cell material because of typically long generation lifetimes. The SGCD structure, which consisted of an extended Schottky diode located next to an MOS-C, was developed and utilized for extracting the surface generation velocity (sg). The measurement is based on recording two C-t transients at Vd = 0 and at Vd = V t , respectively. The structure has a distinct advantage over the conventional PN junction GCD in that it is only slightly more complicated to fabricate and interrogate than a simple MOS-C. It was also demonstrated that steady-state deep-depletion C-V characteristics can be obtained using the SGCD structure. An MOS-C photo/forward-sweep measurement technique was primarily developed to extract the recombination lifetime (rp for n-type substrates) under low-level carrier excess conditions. The new technique is based on the change in inversion capacitance in response to a set of illumination and forward-sweep voltages applied to the MOS-C. The technique conveniently allows one to extract the recombination lifetime under room temperature conditions and was successfully applied to MOS-C’s fabricated on high quality silicon solar cell substrates

Patient Understanding of Benefits, Risks, and Alternatives to Screening Colonoscopy

While several tests and strategies are recommended for colorectal cancer (CRC) screening, studies suggest that primary care providers often recommend colonoscopy without providing information about its risks or alternatives. These observations raise concerns about the quality of informed consent for screening colonoscopy

High-order Discretization of a Gyrokinetic Vlasov Model in Edge Plasma Geometry

We present a high-order spatial discretization of a continuum gyrokinetic Vlasov model in axisymmetric tokamak edge plasma geometries. Such models describe the phase space advection of plasma species distribution functions in the absence of collisions. The gyrokinetic model is posed in a four-dimensional phase space, upon which a grid is imposed when discretized. To mitigate the computational cost associated with high-dimensional grids, we employ a high-order discretization to reduce the grid size needed to achieve a given level of accuracy relative to lower-order methods. Strong anisotropy induced by the magnetic field motivates the use of mapped coordinate grids aligned with magnetic flux surfaces. The natural partitioning of the edge geometry by the separatrix between the closed and open field line regions leads to the consideration of multiple mapped blocks, in what is known as a mapped multiblock (MMB) approach. We describe the specialization of a more general formalism that we have developed for the construction of high-order, finite-volume discretizations on MMB grids, yielding the accurate evaluation of the gyrokinetic Vlasov operator, the metric factors resulting from the MMB coordinate mappings, and the interaction of blocks at adjacent boundaries. Our conservative formulation of the gyrokinetic Vlasov model incorporates the fact that the phase space velocity has zero divergence, which must be preserved discretely to avoid truncation error accumulation. We describe an approach for the discrete evaluation of the gyrokinetic phase space velocity that preserves the divergence-free property to machine precision