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Kinematic hardening in large strain plasticity

A finite strain hyper elasto-plastic constitutive model capable to describe non-linear kinematic hardening as well as nonlinear isotropic hardening is presented. In addition to the intermediate configuration and in order to model kinematic hardening, an additional configuration is introduced - the center configuration; both configurations are chosen to be isoclinic. The yield condition is formulat

Model sensitivity studies regarding the role of the retention coefficient for the scavenging and redistribution of highly soluble trace gases by deep convective cloud systems

The role of the retention coefficient (i.e. the fraction of a dissolved trace gas which is retained in hydrometeors during freezing) for the scavenging and redistribution of highly soluble trace gases by deep convective cloud systems is investigated using a modified version of the Weather Research and Forecasting (WRF) model. Results from cloud system resolving model runs ( in which deep convectio

A new age of old age? : gerotranscendence and the re-enchantment of aging

Gerotranscendence theory is reviewed regarding its content, development, diffusion, impact, empirical results, and ontology. Gerotranscendence theory describes a ''natural'' alteration of consciousness in old age leading to ''wisdom'' and a qualitative break with a mid-life rational and materialist world-view. According to the theory, gerotranscendence is obstructed by a lack of alternative values

Landmark-Based Software for Anatomical Measurements: A Precision Study

The aim of this study was to develop a software program, called Landmarker, which would aid studies of complex anatomical morphometry by simplifying the manual identification of landmarks in 3D images. We also tested its precision on routine magnetic resonance imaging (MRI) scans. To understand human biological variation, there is a need to identify morphological characteristics from the exterior

Neuronal differentiation following transplantation of expanded mouse neurosphere cultures derived from different embryonic forebrain regions.

In vitro, expanded neurospheres exhibit multipotent properties and can differentiate into neurons, astrocytes and oligodendrocytes. In vivo, cells from neurospheres derived from mouse fetal forebrain have previously been reported to predominantly differentiate into glial cells, and not into neurons. Here we isolated stem/progenitor cells from E13.5 lateral ganglionic eminence (LGE), medial ganglio

A numerical study of the effects of stresses induced by moisture gradients in steel-to-timber dowel joints

This experimental study examines the influence of moisture variations on the load-bearing capacity of steel-timber dowel joints. The glulam specimens used to manufacture the joints were first exposed to controlled climate changes. After being stored in the climate chambers, holes were drilled and dowels were inserted. Then, the joints were loaded to failure. The main aim of this study was to inves

Transforming growth factor-beta- and Activin-Smad signaling pathways are activated at distinct maturation stages of the thymopoeisis

Members of the transforming growth factor (TGF)-beta family play pivotal roles in the control of differentiation, proliferation and tolerance in peripheral T cells. Recently, they have been implicated in thymic selection, but their role is so far not well characterized. In the present study, we demonstrate that specific thymocyte populations are under the influence of either the TGF-beta and/or Ac

Decadal vegetation changes in a northern peatland, greenhouse gas fluxes and net radiative forcing

Thawing permafrost in the sub-Arctic has implications for the physical stability and biological dynamics of peatland ecosystems. This study provides an analysis of how permafrost thawing and subsequent vegetation changes in a sub-Arctic Swedish mire have changed the net exchange of greenhouse gases, carbon dioxide (CO2) and CH4 over the past three decades. Images of the mire (ca. 17 ha) and surrou

Expression of ETA and ETB receptor mRNA in human cerebral arteries

The vascular effects of endothelins (ET) are in mammals mediated via two receptor subtypes, endothelin A (ETA, mainly constrictive) and endothelin B (ETB, mainly dilating) receptors. We have examined the presence of ETA and ETB receptor mRNA using the reverse transcription polymerase chain reaction (RT-PCR) in both normal human cerebral arteries and cerebral arteries from patients with cerebrovasc

Sphingomyelinase and ceramidase in the intestinal tract

Sphingomyelin (SM) has emerged as an important source of lipid messengers affecting cell proliferation, differentiation and apoptosis. SM is present in mammalian cell membranes as a lipid constituent and also found as a component of dietary products such as milk, egg and meat. Digestion of SM has been found to have important implications in colon cancer development, gut maturation, and cholesterol

Expanded CAG repeats in exon 1 of the Huntington's disease gene stimulate dopamine-mediated striatal neuron autophagy and degeneration

Huntington's disease (HD) is caused by an expanded CAG repeat in exon 1 of the gene coding for the huntingtin protein. The cellular pathway by which this mutation induces HD remains unknown, although alterations in protein degradation are involved, To study intrinsic cellular mechanisms involved, To study Intrinsic to the mutation, we examined dissociated postnatally derived cultures of striatal n

Association of microsatellite polymorphisms of the human 14q13.2 region with type 2 diabetes mellitus in latvian and finnish populations

A polymorphic microsatellite in intron 6 of the human proteasome core particle PSMA6 gene (HSMS006), and four other microsatellites localized upstream on human chromosome 14q13.2 (HSMS801, HSMS702, HSMS701, HSMS602), were genotyped in 104 type 2 diabetic patients and 129 age-matched control subjects from Latvia and replicated in 91 type 2 diabetic patients and 88 age-matched healthy control subjec

The connection between cutting and clamping forces in turning

The chuck has, for a long time, been considered the weakest link of a lathe. This is mainly due to its two-fold connection, to the machine spindle on the one hand and to the workpiece on the other. An additional limitation of the chuck lies in the incomplete knowledge one has of the load it is exposed to during operation, which usually leads to a less than optimal machining process. Unless our und

Fluid exchanges across the parietal peritoneal and pleural mesothelia

In 31 anesthetized rabbits, after removal of superficial tissues, glass micropipettes filled with 0.5 M NaCl solution and connected to an electrohydraulic servo-null system were used to measure extraperitoneal interstitial fluid pressure (Pi,per) and peritoneal liquid pressure (Pliq,per) at various heights. Linear regressions relating pressure to recording height (H) were Pi,per = 1.07 - 0.27H and

Bootstrapping the Breusch-Godfrey autocorrelation test for a single equation dynamic model: Bootstrapping the Restricted vs. Unrestricted model

We use Monte Carlo methods to study the properties of the bootstrap Breusch-Godfrey test for autocorrelated errors in two versions a) by bootstrapping under the null hypothesis, restricted and b) by bootstrapping under the alternative hypothesis, unrestricted. We use the residual bootstrap for the bootstrap-BG test. Our analysis regarding the size of the test reveals that both bootstrap tests have

Distribution of pancreatic polypeptide and peptide YY.

The cellular distribution of PP and PYY in mammals is reviewed. Expression of PP is restricted to endocrine cells mainly present in the pancreas predominantly in the duodenal portion (head) but also found in small numbers in the gastro-intestinal tract. PYY has a dual expression in both endocrine cells and neurons. PYY expressing endocrine cells occur all along the gastrointestinal tract and are f

Survival, migration and neuronal differentiation of human fetal striatal and cortical neural stem cells grafted in stroke-damaged rat striatum

Stroke is a neurodegenerative disorder and the leading cause of disability in adult humans. Treatments to support efficient recovery in stroke patients are lacking. Several studies have demonstrated the ability of grafted neural stem cells (NSCs) to partly improve impaired neurological functions in stroke-subjected animals. Recently, we reported that NSCs from human fetal striatum and cortex exhib

Effects of fat, beef and fiber in diets on activities of sphingomyelinase, ceramidase and caspase-3 in rat colonic mucosa

Objective: The present study investigates the activity changes of sphingomyelinase (SMase), ceramidase and caspase-3 in colonic mucosa of rats induced by high fat and red meat diets. Method. For a period of 3 weeks, rats were fed protein without fat (control), high fat only, high fat with beef, and high fat with fiber (cellulose) diets. The fat content (22.4%) was constant in the three high fat di