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Local dependencies and Poissonification: a case study

Traffic characterization is of great importance in the analysis and dimensioning of modem telecommunication networks. In this paper, the microdynamics of some sets of traffic are investigated. The approach we use to study the microdynamics is Poissonification, which is away of transforming a point process into a Poisson process locally. We want to gain basic knowledge of how the traffic behaves on

Efficient approximation algorithms for shortest cycles in undirected graphs

We describe a simple combinatorial approximation algorithm for finding a shortest (simple) cycle in an undirected graph. For an undirected graph G of unknown girth k, our algorithm returns with high probability a cycle of length at most 2k for even k and 2k + 2 for odd k, in time O(n(3/2) root logn). Thus, in general, it yields a 2 2/3 approximation. We study also the problem of finding a simple c

Differential activation of signal transducer and activator of transcription (STAT)3 and STAT5 and induction of suppressors of cytokine signalling in T(h)1 and T(h)2 cells

Cytokines direct the differentiation of naive CD4(+) T cells into either IFN-gamma-producing T(h)1 cells or IL-4-producing T(h)2 cells. In this study, we analyzed the activation of signal transducer and activator of transcription (STAT)1, STAT3 and STAT5 (together with STAT4 and STAT6), and the expression of the recently identified suppressor of cytokine signalling (SOCS) proteins, in differentiat

Tuning in to multiple predators: conflicting demands for shell morphology in a freshwater snail.

1. We examined the response to chemical cues from fish and crayfish, two predators with contrasting feeding modes, and their single and combined effect on shell morphology in the freshwater snail Radix balthica. 2. Snails were subjected to four treatments: tench (Tinca tinca), signal crayfish (Pacifastacus leniusculus), a combination of tench and signal crayfish and no predators (control). Shell

Natural convection heat transfer from a thermal heat source located in a vertical plate fin

A steady state conjugate conduction-convection investigation is performed on vertical plate fin in which a small heat source is located. Heat from the fin surface is transferred to the surroundings by laminar natural convection. The governing equations for the problem are the heat conduction equation for the fin and the boundary layer equations, which are continuity, momentum and energy equations,

On the history of supportive therapy

A short history of supportive therapy is delineated by the quadruple division in prehistory, definition, establishment and the phase of integration. Glimpses of the history of the development of the supportive concept are given. It is pointed out that the concept of supportive therapy is stemming from the awkward dichotomy from the ego-psychological paradigm in the psychoanalytic tradition: insigh

Cerebrospinal fluid levels of biomarkers and activity of acetylcholinesterase (AChE) and butyrylcholinesterase in AD patients before and after treatment with different AChE inhibitors

In order to evaluate the biochemical effects of long-term treatment with inhibitors of acetylcholinesterase (AChE) in patients with Alzheimer's disease (AD), we measured the activities of AChE and butyry1cholinesterase (BuChe) and the concentrations of beta-amyloid (1-42), tau and phosphorylated tau proteins in the cerebrospinal fluid (CSF). A total of 91 patients suffering from probable AD of mil

E3B1, a human homologue of the mouse gene product Abi-1, sensitizes activation of Rap1 in response to epidermal growth factor

E3B1, a human homologue of the mouse gene product Abi-1, has been implicated in growth-factor-mediated regulation of the small GTPases p21(Ras) and Rac. E3b1 is a regulator of Rac because it can form a complex with Sos-1 and eps8, and such a Sos-1-e3B1-eps8 complex serves as a guanine nucleotide exchange factor for Rac. In the present study, we found that overexpression of e3B1 in NIH3T3/ EGFR cel

Steam inretreatment of dilute H2SO4-impregnated wheat straw and SSF with low yeast and enzyme loadings for bioethanol production

Conversion of lignocellulosic material to monomeric sugars and finally ethanol must be performed at low cost, i.e, with limited consumption of chemicals, yeast and enzymes while still reaching high yields, if it is to compete with other fuel conversion processes. The objective of this study was thus to investigate ethanol production from steam-pretreated wheat straw by simultaneous saccharificatio

Effects of cardioplegic flushing, storage, and reperfusion on coronary circulation in the pig

BACKGROUND: The aim of the study was to investigate how flush-perfusion of the heart with cold cardioplegic solution, 2 or 12 hours of cold ischemic storage, and 24 hours of reperfusion affect coronary endothelial function and coronary vascular resistance. METHODS: Porcine coronary arterial endothelial and smooth muscle function was studied in organ baths. An adult porcine working heart model was

Desloratadine reduces allergen challenge-induced mucinous secretion and plasma exudation in allergic rhinitis.

BACKGROUND: Rhinorrhea is a key symptom of allergic rhinitis and this disease feature is reduced by antihistamine treatment. The nasal output of fluid in allergic rhinitis is associated with luminal appearance of bioactive molecules emanating from the microcirculation as well as the secretory apparatus. OBJECTIVE: In the present study, we examined the effects of antihistamine treatment on nasal sy

Biological and genetic evolution of HIV type 1 in two siblings with different patterns of disease progression

To investigate the immunological and virological factors that may lead to different patterns of disease progression characteristic of HIV-1-infected children, two HIV-1-infected siblings, a slow and a fast progressor, were followed prospectively before the onset of highly active antiretroviral therapy. Viral coreceptor usage, including the use of CCR5/CXCR4 chimeric receptors, macrophage tropism,

Medical education in Libya: The challenges

The history of medical education in Libya spans over a period of 40 years. Medical schools had a good and promising start in the 1970s. The graduates of the first few classes had a good impact on the health services in Libya. However, the medical schools did not embrace the immense changes that medical education experienced over the last two decades. This article aims to give a background on the m

Core localization and sigma( *) delocalization in the O 1s core-excited sulfur dioxide molecule.

Electron-ion-ion coincidence measurements of sulfur dioxide at discrete resonances near the O 1s ionization edge are reported. The spectra are analyzed using a model based upon molecular symmetry and on the geometry of the molecule. We find clear evidence for molecular alignment that can be ascribed to symmetry properties of the ground and core-excited states. Configuration interaction (CI) calcul

Procedure for simulating divergent-light halos

Divergent-light halos are halos produced by light from nearby light sources, like street lamps being scattered by small crystals of ice floating in the air. The use of "brute-force" Monte Carlo methods to simulate such halos is extremely inefficient, as most scattered rays will not hit the eye of the observer. I present a new procedure for Monte Carlo simulations of divergent-light halos. This pro

Interconversion of Low- and High-Potential Forms of Cytochrome b559 in Tris-Washed Photosystem II Membranes under Aerobic and Anaerobic Conditions

In this study, the reversible conversion between the high- (HP) and low-potential (LP) forms of Cytb559 has been analyzed in Tris-washed photosystem II (PSII) enriched membranes. These samples are deprived of the Mn cluster of the water-oxidizing complex (WOC) and the extrinsic regulatory proteins. The results obtained by application of optical and EPR spectroscopy reveal that (i) under aerobic co

Truncation and fusion of HMGA2 in lipomas with rearrangements of 5q32-->q33 and 12q14-->q15.

Chromosome segment 12q13 -> q15 recombines with many different chromosome bands in lipomas and at least ten recurrent translocations have been identified. The HMGA2 gene is often rearranged, but little is known about the molecular consequences at other breakpoints. Fusion genes between HMGA2 (12q14 -> q15) and LPP (3q27 -> q28), LHFP (13q12) and CMKOR1 (2q37) have been reported. In the present stu