Incentives for Quality through Endogenous Routing

We study how rework routing together with wage and piece rate compensation can strengthen incentives for quality. Traditionally, rework is assigned back to the agent who generates the defect (in a self routing scheme) or to another agent dedicated to rework (in a dedicated routing scheme). In contrast, a novel cross routing scheme allocates rework to a parallel agent performing both new jobs and rework. The agent who passes quality inspection or completes rework receives the piece rate paid per job. We compare the incentives of these rework allocation schemes in a principal-agent model with embedded quality control and routing in a multi-class queueing network. We show that conventional self routing of rework can never induce first-best effort. Dedicated routing and cross routing, however, strengthen incentives for quality by imposing an implicit punishment for quality failure. In addition, cross routing leads to workload allocation externalities and a prisoner’s dilemma, thereby creating highest incentives for quality. Firm profitability depends on capacity levels, revenues, and quality costs. With ample capacity, dedicated routing and cross routing both achieve first-best profit rate, while self routing does not. With limited capacity, cross routing generates the highest profit rate when appraisal, internal failure, or external failure costs are high, while self routing performs best when gross margins are high. When the number of agents increases, the incentive power of cross routing reduces monotonically and approaches that of dedicated routing.queueing networks; routing; Nash equilibrium; quality control; piece rate; epsilon equilibrium.

The examination of Na-Ca effect on some qualitative and quantitative characters in durum wheat plants

The effect of salt stress (NaCl) on shoot height (cm), root length (cm), dry and fresh weight (g), chlorophyll a and b, total chlorophyll (mg-1) and carotenoid amount was investigated in this study. In addition, the positive effects of Ca+2 (20 mM) were also investigated. Triticum durum Desf. Mirzabey, Kunduru-1149, and DH-6 and DH-8, derived from Kunduru-1149 using wide hybridization, were used as plant materials in this study. Arnon-Hoagland solution was used as food source for the plants and various NaCl concentrations (0, 50, 150 and 200 mM) and Ca+2 (as CaCl2) were added to Arnon-Hoagland solution. The research was completed at the end of the fifth week and the effect of NaCl on the root length of genotypes was found to be significant (P<0.05). Ca+2 caused an increase in root length in all NaCl applications, except for the 200 mM NaCl, whereas shoot height decreased with increasing salt concentration, except for the 50 mM NaCl. This character also increased with Ca+2 application significantly. Dry and fresh weight of the plant decreased with increasing salt concentration. Ca+2 ameliorated dry and fresh weight of the plant at 50 mM NaCl in all the genoypes and NaCl doses, except for the Kunduru-1149 and DH-6. The highest increase in total chlorophyll amount was found in 50 mM NaCl + CaCl2 in DH-8 (from 17.29 to 20.14 mg g-1). However, the rate of increase in the amount of carotenoid by the addition of Ca+2 was also determined for each genotype.Key words: Triticum durum Desf., salinity, calcium, chlorophyll, carotenoid

High resolution neurochemical gold staining method for myelin in peripheral and central nervous system at the light- and electron-microscopic level

Myelin is a multilamellar membrane structure primarily composed of lipids and myelin proteins essential for proper neuronal function. Since myelin is a target structure involved in many pathophysiological conditions such as metabolic, viral, and autoimmune diseases and genetic myelin disorders, a reliable myelin detection technique is required that is equally suitable for light- and electron-microscopic analysis. Here, we report that single myelinated fibers are specifically stained by the gold phosphate complex, Black gold, which stains myelin in the brain, spinal cord, and peripheral nerve fibers in a reliable manner. Electron-microscopic and morphometric analyses have revealed that gold particles are equally distributed in the inner, compact, and outer myelin layers. In contrast to Luxol fast blue, the gold dye stains proteinase-sensitive myelin structures, indicating its selective labeling of myelin-specific proteins. Aiming at defining the target of gold staining, we performed staining in several mouse myelin mutants. Gold complex distribution and myelin staining in MBP−/−/shiverer mouse mutants was comparable with that seen in wild-type mice but revealed a more clustered Black gold distribution. This gold staining method thus provides a sensitive and specific high-resolution marker for both central and peripheral myelin sheaths; it also allows the quantitative analysis of myelinated fibers at the light- and electron-microscopic level suitable for investigations of myelin and axonal disorder

Molecular biology of glutathione peroxidase 4: from genomic structure to developmental expression and neural function

Selenoproteins have been recognized as modulators of brain function and signaling. Phospholipid hydroperoxide glutathione peroxidase (GPx4/PHGPx) is a unique member of the selenium-dependent glutathione peroxidases in mammals with a pivotal role in brain development and function. GPx4 exists as a cytosolic, mitochondrial, and nuclear isoform derived from a single gene. In mice, the GPx4 gene is located on chromosome 10 in close proximity to a functional retrotransposome that is expressed under the control of captured regulatory elements. Elucidation of crystallographic data uncovered structural peculiarities of GPx4 that provide the molecular basis for its unique enzymatic properties and substrate specificity. Monomeric GPx4 is multifunctional: it acts as a reducing enzyme of peroxidized phospholipids and thiols and as a structural protein. Transcriptional regulation of the different GPx4 isoforms requires several isoform-specific cis-regulatory sequences and trans-activating factors. Cytosolic and mitochondrial GPx4 are the major isoforms exclusively expressed by neurons in the developing brain. In stark contrast, following brain trauma, GPx4 is specifically upregulated in non-neuronal cells, i.e., reactive astrocytes. Molecular approaches to genetic modification in mice have revealed an essential and isoform-specific function for GPx4 in development and disease. Here we review recent findings on GPx4 with emphasis on its molecular structure and function and consider potential mechanisms that underlie neural development and neuropathological condition

Target- and Maturation-Specific Membrane-Associated Molecules Determine the Ingrowth of Entorhinal Fibers into the Hippocampus

AbstractIn this study the role of membrane-associated molecules involved in entorhinohippocampal pathfinding was examined. First outgrowth preferences of entorhinal neurites were analyzed on membrane carpets obtained from their proper target area, the hippocampus, and compared to preferences on control membranes from brain regions which do not receive afferent connections from the entorhinal cortex. On a substrate consisting of alternating lanes of hippocampal and control membranes, entorhinal neurites exhibited a strong tendency to grow on lanes of hippocampal membrane. These tissue-specific outgrowth preferences were maintained even on membrane preparations from adult brain tissue devoid of myelin. To determine the possible maturation dependence of these membranes, we examined guidance preferences of entorhinal neurites on hippocampal membranes of different developmental stages ranging from embryonic to postnatal and adult. Given a choice between alternating lanes of embryonic (E15–E16) and neonatal (P0–P1) hippocampal membranes, entorhinal neurites preferred to extend on neonatal membranes. No outgrowth preferences were observed on membranes obtained between E19 and P10. From P10 onward there was a reoccurrence of a preference for postnatal membrane lanes when neurites were presented with a choice between P15, P30, and adult membranes (>P60). This choice behavior of entorhinal neurites temporally correlates with the ingrowth of the perforant path into the hippocampus and with the stabilization of this brain area in vivo. Experiments in which postnatal and adult hippocampal membranes were heat inactivated or treated to remove molecules sensitive to phosphatidylinositol-specific phospholipase C demonstrated that entorhinal fiber preferences were controlled in this assay by attractive guidance cues and were independent of phosphatidylinositol-sensitive linked molecules. Moreover, entorhinal neurites displayed a positive discrimination for membrane-associated guidance cues of their target field, thus preferring to grow on membranes from the molecular layer of the dentate gyrus compared with CA3 or hilus membranes. Heat-inactivation experiments indicated that preferential growth of entorhinal axons is due to a specific attractivity of the molecular layer substrate. The data presented demonstrate that outgrowth of entorhinal fibers on hippocampal membranes is target and maturation dependent

Perception of Space in Topological Forms

With recent development of computer technologies there has been change in our notion of materiality. We can define our age as flow of information and architecture capture this flow and creates more complex conceptions and interactions through the space. Recent researches on materialism, typological forms, field gradients and diagramming define a new methodology in design approach, which can respond the dynamism and flow. However architectural form is still inseparable from the way we experience the world, which involves our senses and perceptions. It is possible to adopt cinematic techniques of collage and sequencing in computer-generated forms to create continuous references in spatial understanding

Best practice in the management of behavioural and psychological symptoms of dementia

Behavioural and psychological symptoms of dementia (BPSD) occur in most patients with dementia. They cause great suffering in patients and caregivers, sometimes more so than the cognitive and functional decline inherent to dementia. The clinical features of BPSD include a wide variety of affective, psychotic and behavioural symptoms and signs. The causes and risk factors for BPSD are multiple and include biological, psychological and environmental variables. Frequently, their combination, rather than any specific factor, explains the occurrence of BPSD in an individual patient. Thus, a sound etiopathogenetic investigation including the patient and the family or care team is essential. The aim is to develop an individualized treatment plan using a therapeutic decision tree modified by the individual and environmental risk profile. Still, treatment may be difficult and challenging. Clinical empiricism often steps in where evidence from controlled studies is lacking. Psychosocial treatment approaches are pivotal for successful treatment of BPSD. Often a combination of different non-pharmacological approaches precedes drug treatment (most of which is off-label). Regular assessments of the treatment plan and any prescriptions must be carried out to detect signs of relapse and to stop any medicines that may have become inappropriate. Even with optimal management, BPSD will not disappear completely in some cases and will remain challenging for all involved parties. This article is a narrative review based closely on the interprofessional Swiss recommendations for the treatment of BPSD. To establish the recommendations, a thorough research of the literature has been carried out. Evidence-based data were provided through searches of Medline, Embase, ISI and Cochrane-Database research. Evidence categories of the World Federation of Biological Societies were used. Additionally, the clinical experience of Swiss medical experts was considered

Treatment effects of Ginkgo biloba extract EGb 761® on the spectrum of behavioral and psychological symptoms of dementia: meta-analysis of randomized controlled trials.

ABSTRACTBackground:In randomized controlled trials, Ginkgo biloba extract EGb 761® has been found to be effective in the treatment of behavioral and psychological symptoms of dementia (BPSD). To assess the effects of EGb 761® on specific BPSD, we analyzed data from all randomized, placebo-controlled, at least 20-week, trials of EGb 761® enrolling patients with dementia (probable Alzheimer's disease (AD), probable vascular dementia or probable AD with cerebrovascular disease) who had clinically significant BPSD (Neuropsychiatric Inventory (NPI) total score at least 6). Data were pooled and joint analyses of NPI single item composite and caregiver distress scores were performed by meta-analysis with a fixed effects model. Four trials involving 1628 patients (EGb 761®, 814; placebo, 814) were identified; treatment duration was 22 or 24 weeks; the daily dose of EGb 761® was 240 mg in all trials. Pooled analyses including data from the full analysis sets of all trials (EGb 761®, 796 patients; placebo, 802 patients) revealed significant superiority of EGb 761® over placebo in total scores and 10 single symptom scores. Regarding caregiver distress scores, EGb 761®-treated patients improved significantly more than those receiving placebo in all symptoms except delusions, hallucinations, and elation/euphoria. The benefit of EGb 761® mainly consists of improvement in symptoms present at baseline, but the incidence of some symptoms was also decreased. Twenty two- to twenty four-week treatment with Ginkgo biloba extract EGb 761® improved BPSD (except psychotic-like features) and caregiver distress caused by such symptoms