The problem of determination of the cold low diameter wire (diameter less than 0.1 mm) drawing process parameters for hardly deformable biocompatible magnesium alloys by using the mathematical ...mesoscale model is described in the paper. The originality of the considered alloys (MgCa0.8, Ax30) is the intergranular fracture mechanism associated with small strains (0.07-0.09). In previous authors works it was proven that the material state directly before appearance of the microcracks is in the optimal state from the point of view of the recovery of the plasticity by annealing. The forecasting of this material state in drawing process requires the development of the model of intergranular fracture initiation and using this model in two cases: - modeling of the in-situ tests, what allows calibrating and validating of the model; - modeling of the drawing process, what allows optimizing of the drawing parameters. A new model of the microcracks initiation in mesoscale using the boundary element method is proposed. The in-situ tests, which allowed observing the microstructure evolution during deformation, are used for the calibration and validation purpose. The model was implemented into self-developed FE software Drawing2d, which is dedicated to the drawing process. The results of mesoscale simulation were verified by the experimental drawing process of 0.07 mm diameter wires according to developed technology. It was shown by analysis of microstructure that the model allows forecasting the microcracks initiation during the wire drawing process.Original Abstract: W artykule rozpatrzono problem wyznaczenia parametrow ciagnienia na zimno cienkich drutow (o srednicach mniejszych 0.1 mm) z nisko plastycznych stopow magnezu za pomoca matematycznego modelu w skali mezo. Osobliwoscia utraty spojnosci rozpatrywanych stopow (MgCa0.8, Ax30) jest dominujacy mechanizm pekania po granicach ziaren oraz powstawanie mikropekniec przy malych odksztalceniach (rzedu 0.07-0.09). W poprzednich pracach Autorow 1 udowodniono, ze stan materialu bezposrednio przed powstaniem mikropekniec jest optymalny z punktu widzenia odnawiania plastycznosci w procesie wyzarzania. Prognozowanie takiego stanu materialu w procesie ciagnienia wymaga opracowania modelu powstawania mikropekniec po granicach ziaren i wykorzystania tego modelu w dwoch trybach: - modelowanie testow in-situ, co pozwala na kalibracje i walidacje modelu; - modelowanie procesu ciagnienia, co pozwala na optymalizacje jego parametrow. Zaproponowano nowy model powstawania mikropekniec w skali mezo, oparty o metode elementow brzegowych. Do kalibracji i walidacji modelu wykorzystano badan in-situ, pozwalajace na bezposrednia obserwacje mikrostruktury podczas odksztalcenia. Opracowany model zaimplementowano do Autorskiego programu MES Drawing2d dedykowanemu procesowi ciagnienia. Wyniki symulacji w skali mezo zweryfikowano na podstawie eksperymentalnego ciagnienia drutow o malych srednicach (do 0.07 mm) zgodnego z opracowana technologia. Na podstawie analizy mikrostruktury wykazano, ze opracowany model pozwala przewidywac powstawanie mikropekniec w procesie ciagnienia.
Data on major voting blocks in the German officially listed companies for the end of 1997 and May 2001 are used in order to explore the spatial dimensions of the system of corporate control. Listed ...companies are very unevenly distributed, and their institutional and geographical concentration has not decreased. Holdings of voting blocks in companies are, in turn, getting more and more dispersed, but the majority of corporate control is still intraregional, with the holders of voting rights coming from the same Lander as the controlled corporations. Gravity equations show that distance is a very strong determinant of corporate control links, and its role applies to all types of companies and holders, though to a varying degree. From the perspective of corporate control, the German capital market is very regionalized. Considering that the study spans a short period of time, however, the pace of integration is pronounced.
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•The full simulation study of CCGT integration with ACAES plant.•Obtained air parameters at the outlet of GT compressor.•Identification of CCGT and ACAES plant processes integration point.•Simulated ...hybrid plant operation flexibility showed significant improvement.
The paper presents the research outcome on integration of an Adiabatic Compressed Air Energy Storage system with a Combined Cycle Gas Turbine power plant to increase its operation flexibility. The study demonstrates the novel hybrid CCGT-ACAES plant including an extended operational load level range and increased operation flexibility which supports the power grid to allow more power generation from connected intermittent renewable energy sources. It is also shown that this new hybrid power plant will avoid the Combined Cycle plant gas turbine operating under the low load level. Lowering the minimum hybrid plant operational load level during air and Thermal Energy Storage charging process to the required minimum Heat Recovery Steam Generator load level eliminates the need for Combined Cycle Gas Turbine plant cycling operation increasing the lifetime of the plant components. Adiabatic Compressed Air Energy Storage plant concept is based on proved and well established direct two-tank Thermal Energy Storage technology used in Concentrated Solar Power plants. Improved hybrid plant flexibility is occupied by slight decrease (2%) in the plant efficiency. Further investigation into alternative advanced Thermal Energy Storage systems based on latent heat and chemical reaction heat would offer better hybrid plant round-trip efficiency across operational plant load level range.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
White matter (WM) abnormalities are repeatedly demonstrated across the schizophrenia time-course. However, our understanding of how demographic and clinical variables interact, influence, or are ...dependent on WM pathologies is limited. The most well-known barriers to progress are heterogeneous findings due to small sample sizes and the confounding influence of age on WM. The present study leverages access to the harmonized diffusion magnetic-resonance-imaging data and standardized clinical data from 13 international sites (597 schizophrenia patients (SCZ)). Fractional anisotropy (FA) values for all major WM structures in patients were predicted based on FA models estimated from a healthy population (n = 492). We utilized the deviations between predicted and real FA values to answer three essential questions. (1) "Which clinical variables explain WM abnormalities?". (2) "Does the degree of WM abnormalities predict symptom severity?". (3) "Does sex influence any of those relationships?". Regression and mediator analyses revealed that a longer duration-of-illness is associated with more severe WM abnormalities in several tracts. In addition, they demonstrated that a higher antipsychotic medication dose is related to more severe corpus callosum abnormalities. A structural equation model revealed that patients with more WM abnormalities display higher symptom severity. Last, the results exhibited sex-specificity. Males showed a stronger association between duration-of-illness and WM abnormalities. Females presented a stronger association between WM abnormalities and symptom severity, with IQ impacting this relationship. Our findings provide clear evidence for the interaction of demographic, clinical, and behavioral variables with WM pathology in SCZ. Our results also point to the need for longitudinal studies, directly investigating the casualty and sex-specificity of these relationships, as well as the impact of cognitive resiliency on structure-function relationships.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
1 Dept. of Hematology, University Hospital, Basel, Switzerland
2 Service dHematologie, Hopitaux Universitaires de Genève, Geneva, Switzerland
3 Dept. of Childhood Hematology and Oncology, Wroclaw ...Medical University, Wroclaw, Poland
4 Dept. de Hematologie, Hotel Dieu, Nantes, France
5 Dept. of Haematology and Stem Cell Transplant, St. Laszlo Hospital, Budapest, Hungary
6 Bone Marrow Transplantation Centre, University Hospital Eppendorf, Hamburg, Germany
7 Dept. of Hematology, University Hospital, Lund, Sweden
8 Dept. of Hematology, Addenbrookes Hospital, Cambridge, United Kingdom
9 Dept. of Hematology, Faculty of Medicine, Ankara University, Ankara, Turkey
10 Instituto di Ematologia, Universita Cattolica S. Cuore, Rome, Italy
11 Service de Pediatrie Hematologie-Oncologie, Hopital de Hautepierre, Strasbourg, France
12 Service dHematologie, Greffe, Hospital Saint Louis, Paris, France
Correspondence: André Tichelli, Hematology, University Hospital, CH 4031-Basel, Switzerland. E-mail: tichelli{at}datacomm.ch
Background: Long-term outcome after hematopoietic stem cell transplantation including late transplant-related events is of increasing interest. The aim of this study was to evaluate the incidence of cardiovascular events after allogeneic HSCT and to search for their risk factors.
Design and Methods: This is a retrospective mutlicenter European Group of Blood and Marrow Transplantation (EBMT) analysis, including 548 long-term survivors treated in ten EBMT transplant centers, who underwent hematopoietic stem cell transplantation between 1990 and 1995 and survived 1 year after the transplant. All arterial events occurring after hematopoietic stem cell transplantation (cerebral, coronary, peripheral) were reported.
Results: Twenty (3.6%) out of 548 patients had a cardiovascular event in at least one arterial territory. The median age at occurence of cardiovascular events was 54 years (range, 41–70). The cumulative incidence of a first arterial event 15 years after hematopoietic stem cell transplantation was 6% (95% CI, 3%–10%). The cumulative incidence for patients with a high global cardiovascular risk score, defined as having 50% of the risk factors (arterial hypertension, diabetes, dys-lipidemia, increased body-mass index, physical inactivity, smoking) was 17%, as compared to 4% in those with a low risk score. In multivariate analysis age older than 30 years at last follow-up, and a high global cardiovascular risk score were associated with, respectively, 6.4-fold and 9.8-fold increases in the risk of an arterial event.
Conclusions: Long-term survivors after allogeneic hematopoietic stem cell transplantation are likely to have an increased risk of premature cardiovascular accidents.
Key words: stem cell transplantation, cardiovascular, late effects, long-term survivors.
Related Article
Cardiovascular disease after hematopoietic cell transplantation – lessons learned
Saro H. Armenian, Smita Bhatia
Haematologica 2008 93: 1132-1136.
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Flow coefficients vn of the orders n = 1 – 6 are measured with the High-Acceptance Spectrometer (HADES) at GSI for protons, deuterons, and tritons as a function of centrality, transverse momentum, ...and rapidity in Au + Au collisions at √sNN = 2.4 GeV. Combining the information from the flow coefficients of all orders allows us to construct for the first time, at collision energies of a few GeV, a multidifferential picture of the angular emission pattern of these particles. It reflects the complicated interplay between the effect of the central fireball pressure on the emission of particles and their subsequent interaction with spectator matter. The high precision information on higher order flow coefficients is a major step forward in constraining the equation of state of dense baryonic matter.
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Yeast tolerance to Cr (III) and Cr (VI) as well as chromium accumulation potential were shown to depend on treatment time, metal concentration, biomass density and the phase of growth. Kinetic ...studies as exemplified by
Pichia guilliermondii ATCC 201911 revealed a biphasic mode of Cr (III) uptake: a rapid sorption phase was followed by a slow process of accumulation, in which the contribution of the cell-bound Cr fraction increased, while the total cellular Cr level remained constant. Cr (VI) uptake was characterized by a time-dependent increase of total Cr and by a constant fractional contribution of the cell-adsorbed chromium, which suggests that the amount of cell-accumulated Cr also tended to increase over time. The resistance to Cr and metal accumulation levels were substantially elevated for a given strain when cultures were treated at high initial biomass densities (1
mg dry weight/ml) of exponentially proliferating cells. Maximum accumulation capabilities ranged between 4.0 and 13
mg Cr (III)/g dry weight and 2–6.7
mg Cr (VI)/g dry weight. The total cell-accumulated Cr contained 29.3% and 52.3% of organically bound chromium for the treatment of
P. guilliermondii with Cr (III) and Cr (VI), respectively. Selected yeast strains, under specified physiological conditions, can be applied for bioremediation of environmental Cr contamination, and might be useful too for attempts to obtain chromium-enriched biomass containing biostabilized and nontoxic Cr forms for nutritional applications.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This study explored how memory for actions in children with autism spectrum disorder (ASD) and typically developing children might benefit from self-performance and experimenter demonstration, and ...whether these groups possess metamemory knowledge of their performance levels in this task. Children with autism were less accurate on the action memory task when they carried out each action themselves during encoding, or when no actions were implemented during this phase, but this difference was abolished when the experimenter demonstrated each action during encoding. Despite clear difficulties in the self-performed condition relative to typical children, the group with ASD also showed a beneficial effect of performing the actions themselves during instruction. Finally, children with autism were as accurate as typical children in judging the accuracy of their own memory performance, indicating an absence of metamemory difficulties for this task.
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The effect of invasive opportunistic predators may include population changes in both native prey and native predators as well as alteration of predator–prey interactions. We analyzed the activity of ...native magpie Pica pica and changes in population, nest sites and nesting success probability of native waterbirds (namely: grebes, ducks, rails and native gulls) in response to the population growth of the invasive Caspian gull Larus cachinnans. The study was carried out at a reservoir in southern Poland and at a similar control reservoir where the Caspian gull was absent. Both the invasive gulls and the native magpie are opportunistic predators of nests of native waterbirds. The population increase of the invasive gull led to a decline in the population of native black-headed gulls Larus ridibundus only. However, the invasive gull displaced all the native species from the breeding islets located in the central part of the reservoir to islets located close to the shoreline. The latter were frequently visited by magpies, which depredated on nests along the shores, leading to an up to threefold decrease in nesting success as compared with nests located in the central area of the invaded reservoir. Predation by Caspian gulls was rarely observed. Thus, the invasion of Caspian gull caused complex direct and indirect effects on the waterbird community that included competition for breeding sites, changes in the spatial distribution of nests and alteration of predation rate by native predators. Moreover, the effects of invasion may not be reflected by changes in population size of native species.
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