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Path generation issues for survivable network design

Link dimensioning and routing problems in resilient network design are considered. Reliable network operation is ensured by means of flow restoration which is performed on preselected protection (backup) paths that can absorb traffic overflows from failed primary paths. Backup and primary flows use separated link capacities, and can be split among many paths. In the paper, two restoration models a

Neuroendocrine cells and nerves in the prostate of the guinea pig: effects of peripheral denervation and castration

BACKGROUND: Neuroendocrine (NE) cells and nerves in the prostate gland are thought to play a central role in the regulation of growth, cellular differentiation and homeostasis of secretory activity. The objective of this experimental study was to describe the effects of peripheral denervation and castration on NE cells and nerves in the guinea pig prostate. METHODS: Guinea pigs underwent sham-oper

Simulation of charged colloids in solution

Physicochemical properties of solutions of charged colloids are often dominated by the electrostatic interactions present in such systems. A full determination of these properties constitutes a highly nontrivial many-body problem involving long-range interactions. In electrostatically strongly coupled systems, it is essential to explicitly include both the charged colloids and the small ions in th

Review of the self-organizing map (SOM) approach in water resources: Analysis, modelling and application

The use of artificial neural networks (ANNs) in problems related to water resources has received steadily increasing interest over the last decade or so. The related method of the self-organizing map (SOM) is an unsupervised learning method to analyze, cluster, and model various types of large databases. There is, however, still a notable lack of comprehensive literature review for SOM along with

Operating charts for continuous sedimentation III: control of step inputs

The main purposes of a clarifier-thickener unit is that it should produce a high underflow concentration and a zero effluent concentration. The main difficulty in the control of the clarification-thickening process (by adjusting a volume flow) is that it is nonlinear with complex relations between concentrations and volume flows via the solution of a PDE - a conservation law with a source term and

Characterization of chemical substitution of hydroxypropyl cellulose using enzymatic degradation

The distribution of substituents along the polymer backbone will have a strong influence on the properties of modified cellulose. Endoglucanases were used to degrade a series of hydroxypropyl cellulose (HPC) derivatives with a high degree of substitution. The HPCs were characterized with cloud-point analysis prior to degradation. The extent of enzymatic degradation was determined with size-exclusi

Overexpression of CXCR4 on human CD34(+) progenitors increases their proliferation, migration, and NOD/SCID repopulation

A major limitation to clinical stem cell-mediated gene therapy protocols is the low levels of engraftment by transduced progenitors. We report that CXCR4 overexpression on human CD34(+) progenitors using a lentiviral gene transfer technique helped navigate these cells to the murine bone marrow and spleen in response to stromal-derived factor 1 (SDF-1) signaling. Cells overexpressing CXCR4 exhibite

The prognostic value of different forms of prostate specific antigen and their ratios in patients with prostate cancer

OBJECTIVE: To assess the prognostic value for patient survival of different forms of PSA and ratios thereof, before treatment for prostate cancer, by considering the forms and ratios both as independent markers and by comparing them with other commonly used prognostic markers, e.g. tumour grade, local stage (T-stage) and absence or presence of skeletal metastases (M-stage). PATIENTS AND METHODS: B

Prognostic factors in invasive cutaneous malignant melanoma: a population-based study and review

A population-based study from Sweden identified 711 patients with cutaneous malignant melanoma diagnosed in 1965, 1975, 1985 and 1989. Prognostic factors were evaluated and a review of the literature was performed. On univariate analysis, thick tumours (> 0.8 mm) (odds ratio [OR] 1.8, 95% confidence interval [CI] 1.6-2.1), increasing Clark level (OR 1.8, 95% CI 1.6-2.0), ulceration (OR 1.8, 95% CI

Examination of aerosol effects on precipitation in deep convective clouds during the 1997 ARM summer experiment

It has been generally accepted that increasing aerosols suppress precipitation. The aerosol-induced precipitation suppression was suggested by the study of shallow stratiform clouds. Recent studies of convective clouds showed increasing aerosols could increase precipitation. Those studies showed that intense feedbacks between aerosols and cloud dynamics led to increased precipitation in some cases

Developing a kinetic alternative in modeling soil aluminium.

Soil chemistry models often use gibbsite solubility and similar equilibrium models to predict Al concentrations in soil solution. A kinetic alternative was developed with the goal of finding universal rate constants instead of the site- and depth-specific solubility constants usually associated with the equilibrium approach. The behavior of the two approaches was studied within the framework of th

Cost of treatment of schizophrenia in six European countries

Background and aims: As part of an RCT in six European sites, the direct mental health care cost for 422 patients with schizophrenia was analysed according to how total and medication costs differed across sites and which variables were likely to predict total or service-specific costs. Method: Service use was recorded continuously during a 12-month follow-up. Prescribed psychotropic medication wa

Expression patterns of the human sarcoma-associated genes FUS and EWS and the genomic structure of FUS

FUS (TLS) was first identified as the 5'-part of a fusion gene with CHOP (GADD153, DDIT3) in myxoid liposarcomas with t(12; 16)(q13; p11). Homologies were found with the EWS oncogene, which is rearranged in Ewing sarcomas and other neoplasias. The genomic structure of FUS shows extensive similarities with that of EWS, but the exon/intron structures differ in the 5' parts, and overall FUS is smalle

Pharmacokinetics, pharmacodynamics and clinical effects of the oral direct thrombin inhibitor ximelagatran in acute treatment of patients with pulmonary embolism and deep vein thrombosis

Introduction: Ximelagatran is a novel, oral direct thrombin inhibitor that is currently being investigated for the prophylaxis and treatment of thromboembolic events. This study evaluated the pharmacokinetics, pharmacodynamics, and clinical effects of melagatran, the active form of ximelagatran, in patients with both deep vein thrombosis (DVT) and pulmonary embolism (PE). Materials and methods: In

Crystal structure of ferrochelatase: the terminal enzyme in heme biosynthesis

BACKGROUND: The metallation of closed ring tetrapyrroles resulting in the formation of hemes, chlorophylls and vitamin B12 is catalyzed by specific enzymes called chelatases. Ferrochelatase catalyzes the terminal step in heme biosynthesis by inserting ferrous ion into protoporphyrin IX by a mechanism that is poorly understood. Mutations in the human gene for ferrochelatase can result in the diseas

Screening for Infants With Developmental Deficits and/or Autism A Swedish Pilot Study.

The purpose of this study was to develop an instrument (SEEK) for the early detection of developmental deficits and/or autistic spectrum disorders among children by the age of 8 months at eight child health care centers in southern Sweden. Health visitors, trained by the research team, screened 312 infants. SEEK captured 5 infants with several points. Twenty-one percent of the infants obtained at