271 research outputs found
1/m_Q Corrections to the Heavy-to-Light-Vector Transitions in the HQET
Within the HQET, the heavy to light vector meson transitions are
systematically analyzed to the order of 1/m_Q. Besides the four universal
functions at the leading order, there are twenty-two independent universal form
factors at the order of 1/m_Q. Both the semileptonic decay B->\rho which is
relevant to the |V_{ub}| extraction, and the penguin induced decay B -> K^*
which is important to new physics discovering, depend on these form factors.
Phenomenological implications are discussed.Comment: RevTeX, 9 pages, no figure
A STUDY ON FACTORS INFLUENCING THE DETERMINATION OF MOISTURE CONTENT OF FIBROUS PEAT
Fibrous peat is an undrained peat that usually possesses very high moisture content. However, not all experimental procedures are applicable for determination of moisture content of fibrous peat. This research is aimed at examining the determination of insitu moisture content of fibrous peat using field measurements. The peat soil samples were collected at shallow depths from Asajaya at Kota Samarahan
and Taman Kopodims at Matang , Kuching Sarawak by using peat auger. The laboratory tests such as determination of moisture content, fiber content, particle density and ash content were conducted on the collected samples in order to establish relationships between the parameters. Undisturbed peat samples from Matang were subjected to falling head permeability test to determine the saturated permeability.
The saturated sample were then allowed to drain freely to simulate the moisture loss possible during sampling when samples were brought out of boreholes. The test results showed that moisture content varies according to the drying temperature and position of the soil sample (top, middle and bottom) during sampling. Comparing samples from both locations, peat soil from Kota Samarahan possessed higher
moisture content. The saturated permeability of peat sample was in the range of 2.62 – 3.05 cm/s. The free draining trial showed that moisture loss during sampling significantly influence the moisture content measurement. The variation in value of moisture content for fibrous peat
may occurs due to several factors such as existing ground water table, sampling method by boring, existing standard test procedure which is not suitable for peat soils requirement and also because of the physical properties which varied according to depth of soil
Pseudohipoparatiroidismo en niños: manifestaciones clínicas e implicancias del tratamiento
El pseudohipoparatiroidismo es una enfermedad hereditaria caracterizada por presentar resistencia a la hormonaparatiroidea que se manifiesta por hipocalcemia, hiperfosfatemia y niveles elevados de PTH. Los pacientes pueden presentar características fenotípicas de osteodistrofia hereditaria de Albright y tener asociadas otras resistencias hormonales. En este trabajo se analizan las características clínicas y bioquímicas de 13 niños afectados de la enfermedad, como así también la implicancia del tratamiento. El diagnóstico temprano, la detección oportuna de resistencias hormonales asociadas y el control periódico de los pacientes,son de relevancia para promover el crecimiento y disminuir las secuelas de la hipocalcemia.Fil: Tau, Cristina Catalina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Geniuk, N.. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Viterbo, Gisela Lorena. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Guercio, Gabriela Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Belgorosky, Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentin
Liquid-microjet photoelectron spectroscopy of the green fluorescent protein chromophore
Green fluorescent protein (GFP), the most widely used fluorescent protein for in vivo monitoring of biological processes, is known to undergo photooxidation reactions. However, the most fundamental property underpinning photooxidation, the electron detachment energy, has only been measured for the deprotonated GFP chromophore in the gas phase. Here, we use multiphoton ultraviolet photoelectron spectroscopy in a liquid-microjet and high-level quantum chemistry calculations to determine the electron detachment energy of the GFP chromophore in aqueous solution. The aqueous environment is found to raise the detachment energy by around 4 eV compared to the gas phase, similar to calculations of the chromophore in its native protein environment. In most cases, electron detachment is found to occur resonantly through electronically excited states of the chromophore, highlighting their importance in photo-induced electron transfer processes in the condensed phase. Our results suggest that the photooxidation properties of the GFP chromophore in an aqueous environment will be similar to those in the protein
Recent developments of the Hierarchical Reference Theory of Fluids and its relation to the Renormalization Group
The Hierarchical Reference Theory (HRT) of fluids is a general framework for
the description of phase transitions in microscopic models of classical and
quantum statistical physics. The foundations of HRT are briefly reviewed in a
self-consistent formulation which includes both the original sharp cut-off
procedure and the smooth cut-off implementation, which has been recently
investigated. The critical properties of HRT are summarized, together with the
behavior of the theory at first order phase transitions. However, the emphasis
of this presentation is on the close relationship between HRT and non
perturbative renormalization group methods, as well as on recent
generalizations of HRT to microscopic models of interest in soft matter and
quantum many body physics.Comment: 17 pages, 5 figures. Review paper to appear in Molecular Physic
BGWM as Second Constituent of Complex Matrix Model
Earlier we explained that partition functions of various matrix models can be
constructed from that of the cubic Kontsevich model, which, therefore, becomes
a basic elementary building block in "M-theory" of matrix models. However, the
less topical complex matrix model appeared to be an exception: its
decomposition involved not only the Kontsevich tau-function but also another
constituent, which we now identify as the Brezin-Gross-Witten (BGW) partition
function. The BGW tau-function can be represented either as a generating
function of all unitary-matrix integrals or as a Kontsevich-Penner model with
potential 1/X (instead of X^3 in the cubic Kontsevich model).Comment: 42 page
Field trial of Machine-Learning-assisted and SDN-based Optical Network Planning with Network-Scale Monitoring Database
Reverse Engineering a Signaling Network Using Alternative Inputs
One of the goals of systems biology is to reverse engineer in a comprehensive fashion the arrow diagrams of signal transduction systems. An important tool for ordering pathway components is genetic epistasis analysis, and here we present a strategy termed Alternative Inputs (AIs) to perform systematic epistasis analysis. An alternative input is defined as any genetic manipulation that can activate the signaling pathway instead of the natural input. We introduced the concept of an “AIs-Deletions matrix” that summarizes the outputs of all combinations of alternative inputs and deletions. We developed the theory and algorithms to construct a pairwise relationship graph from the AIs-Deletions matrix capturing both functional ordering (upstream, downstream) and logical relationships (AND, OR), and then interpreting these relationships into a standard arrow diagram. As a proof-of-principle, we applied this methodology to a subset of genes involved in yeast mating signaling. This experimental pilot study highlights the robustness of the approach and important technical challenges. In summary, this research formalizes and extends classical epistasis analysis from linear pathways to more complex networks, facilitating computational analysis and reconstruction of signaling arrow diagrams
Risk and prognostic significance of tuberculosis in patients from The TREAT Asia HIV Observational Database
10.1186/1471-2334-9-46BMC Infectious Diseases94
On the Low Surface Magnetic Field Structure of Quark Stars
Following some of the recent articles on hole super-conductivity and related
phenomena by Hirsch \cite{H1,H2,H3}, a simple model is proposed to explain the
observed low surface magnetic field of the expected quark stars. It is argued
that the diamagnetic moments of the electrons circulating in the electro-sphere
induce a magnetic field, which forces the existing quark star magnetic flux
density to become dilute. We have also analysed the instability of
normal-superconducting interface due to excess accumulation of magnetic flux
lines, assuming an extremely slow growth of superconducting phase through a
first order bubble nucleation type transition.Comment: 24 pages REVTEX, one .eps figure, psfig.sty is include
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