On strictly positive solutions for some semilinear elliptic problems

Abstract.

LetBbe a ball in IR(N) ,N≥1, letmbe a possibly discontinuous and unbounded function that changes sign inBand let 0 <p<1. We study existence and nonexistence of strictly positive solutions for
semilinear elliptic problems of the form−Δu=m(x)u^p in B, u=0 on ∂B.

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Stable Phase Equilibrium of the Aqueous Quaternary System (MgCl2+ MgSO4+ MgB6O10+H2O) at 323.15 K

ABSTRACT:

The solubilities and relevant physicochemical properties including density and pH values of the aqueous quaternary system (MgCl2+ MgSO4+ MgB6O10+H2O) at 323.15 K were determined for thefirst time with the method of isothermal dissolution. According to the experimental results, the dry-salt-phase diagram, water-phase diagram, and physicochemical properties versus composition diagrams were plotted. It was found that there are three three-salt cosaturated invariant points, seven univariant solubility isotherm curves, and five stable crystallization fields corresponding to bischofite (MgCl2, 6H2O, Bis), kieserite (MgSO4 3H2O, Kie), tetrahydrite (MgSO434H2O, Tet), hexahydrite (MgSO436H2O, Hex), and mcallisterite (Mg(B6O7)(OH)6 4.5H2O, Mca). Neither solid solution nor double salts were found. On the basis of the extended Harvie Weare (HW) model and its temperature-dependent equation, single-salt parametersβ

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Fetal dopaminergic transplantation trials and the future of neural grafting in Parkinson’s disease

Introduction

As we move towards an era of stem cell-based treatments for neurodegenerative disorders of the CNS, particularly Parkinson’s disease, the rationale for use of dopaminergic cell-based approaches to treat this disorder needs to be considered. Allografting of fetal ventral mesencephalic tissue as a dopaminergic replacement therapy in Parkinson’s disease was first undertaken more than 20 years ago  and since then many patients have had this procedure. The results from these interventions have been variable and, thus, the merits of this approach have been both questioned and championed. In this Review, we describe the rationale for use of fetal ventral mesencephalic allografts and discuss how, as our knowledge of Parkinson’s disease has changed, our understanding has altered on how best to use this repair strategy for patients. This understanding is based on a better definition of the nature and extent of problems in Parkinson’s disease but also has entailed a critical reappraisal of data from transplant trials that have already been undertaken. This reanalysis has led us to plan a clinical trial sponsored by the European Union (TRANSEURO), which will include careful selection of patients (age, stage of disease, type of Parkinson’s disease), tissue preparation (number of cells grafted, dopaminergic vsserotonergic content of the graft), tissue placement (location, tract numbers), graft support (storage media, immunotherapy after grafting), and trial design (numbers of patients, follow-up time, endpoints).
The discussions and analyses that have led up to this new trial form the basis for this Review.

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Methodologies to Optimize Automated Guided Vehicle Scheduling and Routing Problems: A Review Study

Abstract

Automated guided vehicles (AGVs) are used as a material handling device in flexible manufacturing systems. Traditionally, AGVs were mostly used at manufacturing systems, but currently other
applications of AGVs are extensively developed in other areas, such as warehouses, container terminals and transportation systems. This paper discusses literature related to different methodologies to optimize AGV systems for the two significant problems of scheduling and routing at manufacturing, distribution, transshipment and transportation systems. We categorized the methodologies into mathematical methods (exact and heuristics), simulation studies, metaheuristic techniques and artificial intelligent based approaches

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2D systems based robust iterative learning control using noncausal finite-time interval data

Abstract

This paper uses a 2D system setting in the form of repetitive process stability theory to design an iterative learning control law that is robust against model uncertainty. In iterative learning control the same finite duration operation, known as a trial over the trial length, is performed over and over again with resetting to the starting location once each is complete, or a stoppage at the end of the current trial before the next one begins. The basic idea of this form of control is to use information from the previous trial, or a finite number thereof, to compute the control input for the next trial. At any instant on the current trial, data from the complete previous trial is available and hence non causal information in the trial length indeterminate can be used. This paper also shows how the new 2D system based design algorithms provide a setting for the effective deployment of such information.

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Absence of typical unfolded protein response in primary cultured cystic fibrosis airway epithelial cells

Abstract

We examined whether the unfolded protein response is activated in cells expressing incorrectly folded cystic fibrosis transmembrane conductance regulator. Airway epithelial cells from three control and three CF patients homozygous for theDF508 mutation were tested.
There were no differences in protein expression of the pro-apoptotic factor C/EBP homologous protein (CHOP) or the endoplasmic reticulum (ER) chaperone binding Ig protein. Nor were there differences in phosphorylation of protein kinase R-like ER kinase or eukaryotic initiation factor-2a, or the splicing of X-box binding protein (XBP)-1. However, CF cells showed increased mRNA expression of CHOP and XBP-1. A proteasome inhibitor increased CHOP expression in CF cells, suggesting that enhanced proteasome activation is responsible for the observed post-transcriptional regulation. Finally, CF cells were resistant to apoptosis, suggesting that post-transcriptional regulation of CHOP prevents apoptosis. While CHOP and XBP-1 mRNA expression is increased in CF cells, the classic UPR is not present

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