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1.
The aim of the present study was to assess the prognostic relevance of relatives' interactive behaviour towards the patient, as covered by the Münster Family Interview (MFI), to the further course of the schizophrenic illness. The MFI is a family interview (of the whole family, including the patient) designed to record the emotional family atmosphere based on the concept of expressed emotion (EE). The ratings take place directly after the interview on five scales (criticism, hostility, overinvolvement, resignation and warmth), the resignation scale being added to the 'classic' EE scales. Ninety-nine families of outpatients diagnosed with schizophrenia according to the DSM-III were examined with the MFI during a home visit. The patients were seen 1 and 2 years after the first examination. The target criteria selected for the prognostic significance of the interaction measurements were: rehospitalisation within 2 years; extent of symptoms after 1 year, and psychosocial skills after 1 year. The significance of the interaction dimensions was verified in regression models. The control variable used in the regression models was the Strauss-Carpenter scale. Regression models were produced for the total group and for a subgroup of moderately ill patients. All target criteria yielded serviceable prediction models. The most important variable for prediction was the control variable, the Strauss-Carpenter scale. However the interaction variables made additional contributions to the prognosis, especially in the subgroup of moderately ill patients. The best MFI scale for all the outcome criteria was resignation; criticism predicted only the symptomatology, and emotional overinvolvement the level of social functioning after 1 year. In conclusion, practical work with families of schizophrenic patients should emphasise the protective function of relatives towards patients more strongly. 相似文献
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3.
BerlinMOD: a benchmark for moving object databases 总被引:2,自引:0,他引:2
Christian Düntgen Thomas Behr Ralf Hartmut Güting 《The VLDB Journal The International Journal on Very Large Data Bases》2009,18(6):1335-1368
This document presents a method to design scalable and representative moving object data (MOD) and two sets of queries for
benchmarking spatio-temporal DBMS. Instead of programming a dedicated generator software, we use the existing Secondo DBMS to create benchmark data. The benchmark is based on a simulation scenario, where the positions of a sample of vehicles
are observed for an arbitrary period of time within the street network of Berlin. We demonstrate the data generator’s extensibility
by showing how to achieve more natural movement generation patterns, and how to disturb the vehicles’ positions to create
noisy data. As an application and for reference, we also present first benchmarking results for the Secondo DBMS. Whereas the benchmark focuses on range queries, we demonstrate its ability to incorporate new future classes of queries
by presenting a preliminary extension handling various nearest neighbour queries. Such a benchmark is useful in several ways:
It provides well-defined data sets and queries for experimental evaluations; it simplifies experimental repeatability; it
emphasizes the development of complete systems; it points out weaknesses in existing systems motivating further research.
Moreover, the BerlinMOD benchmark allows one to compare different representations of the same moving objects. 相似文献
4.
Writing with Fluid: Structuring Hydrogels with Micrometer Precision by AFM in Combination with Nanofluidics
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Nicolas Helfricht Andreas Mark Marina Behr Andreas Bernet Hans‐Werner Schmidt Georg Papastavrou 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(31)
Hydrogels have many applications in biomedical surface modification and tissue engineering. However, the structuring of hydrogels after their formation represents still a major challenge, in particular due to their softness. Here, a novel approach is presented that is based on the combination of atomic force microscopy (AFM) and nanofluidics, also referred to as FluidFM technology. Its applicability is demonstrated for supramolecular hydrogel films that are prepared from low‐molecular weight hydrogelators, such as derivates of 1,3,5‐benzene tricarboxamides (BTAs). BTA films can be dissolved selectively by ejecting alkaline solution through the aperture of a hollow AFM‐cantilever connected to a nanofluidic controller. The AFM‐based force control is essential in preventing mechanical destruction of the hydrogels. The resulting “chemical writing” process is studied in detail and the influence of various parameters, such as applied pressure and time, is validated. It is demonstrated that the achievable structuring precision is primarily limited by diffusion and the aperture dimensions. Recently, various additive techniques have been presented to pattern hydrogels. The here‐presented subtractive approach can not only be applied to structure hydrogels from the large class of reversibly formed gels with superior resolution but would also allow for the selective loading of the hydrogels with active substances or nanoparticles. 相似文献
5.
Reproducible and optimized complex formation between polyanionic DNA and a polycationic vector is a key aspect of nonviral gene transfer systems. To this end, several factors relevant to in vivo delivery have been tested repeatedly on several cell types. Gene transfer with a lipopolyamine (transfectam) in the presence of serum was increased over 10-fold by sequential addition of the lipid to DNA. Paradoxically, high complex concentrations (> 200 micrograms DNA/ml) led to large enhancements too, which points to the fact that formation of productive complexes is a slow process. Each parameter, more than compensates for the decreased efficiency generally observed with nonviral vectors in serum. Transfectam and PEI (polyethylenimine)-mediated transfection also improved after mild centrifugation of the complexes on to the cells. These individual factors were shown to be essentially multiplicative, leading altogether to approximately a 1000-fold transfection increase with a luciferase reporter gene. Finally, 25 cell lines and primary cells (including fibroblasts, hepatocytes and endothelial cells) were successfully transfected over a five orders-of-magnitude efficiency range, From this large set of data, a general relation between the overall transfection level (as measured by luciferase reporter gene expression) and the fraction of transfected cells (histochemically stained for beta-galactosidase) could be inferred. Finally, transfectam and PEI displayed similar trends over this large range of efficiencies, which reinforces the hypothesis of a common transfection mechanism where the key endosome-releasing stop occurs through a "proton sponge' effect. 相似文献
6.
M. Probst M. Lülfesmann M. Nicolai H.M. Bücker M. Behr C.H. Bischof 《Computer Methods in Applied Mechanics and Engineering》2010,199(17-20):997-1005
The difficulties arising in the numerical solution of PDE-constrained shape optimization problems are manifold. Key ingredients are the optimization strategy and the shape deformation method. Furthermore, the robustness of the optimal shape with respect to simulation parameters is of great interest. In this paper, we consider fluid flows described by the incompressible Navier–Stokes equations. Previous studies on artificial bypass grafts indicated the need for specific constitutive models to account for the non-Newtonian nature of blood; in particular, the constitutive model was shown to affect the solution of the shape optimization problem. We employ a shape optimization framework that couples a finite element solver with quasi-Newton-type optimizers and a Bezier spline shape parametrization. To compute derivatives of the optimal shapes with respect to viscosity, we transform the entire optimization framework by combining the automatic differentiation tools Adifor2 and TAPENADE. We demonstrate the impact of the geometry parametrization and of geometric constraints on the optimization outcome. Finally, we employ the transformed framework to compute the sensitivity of the optimal shape of bypass grafts with respect to kinematic viscosity. The resulting sensitivities predict very accurately the influence of viscosity changes on the optimal shape. The proposed methodology provides a powerful tool to further investigate the necessity of intricate constitutive models by taking derivatives with respect to model parameters. 相似文献
7.
The radiation budget at the earth surface is an essential climate variable for climate monitoring and analysis as well as for verification of climate model output and reanalysis data. Accurate solar surface irradiance data is a prerequisite for an accurate estimation of the radiation budget and for an efficient planning and operation of solar energy systems.This paper describes a new approach for the retrieval of the solar surface irradiance from satellite data. The method is based on radiative transfer modelling and enables the use of extended information about the atmospheric state. Accurate analysis of the interaction between the atmosphere, surface albedo, transmission and the top of atmosphere albedo has been the basis for the new method, characterised by a combination of parameterisations and “eigenvector” look-up tables. The method is characterised by a high computing performance combined with a high accuracy. The performed validation shows that the mean absolute deviation is of the same magnitude as the confidence level of the BSRN (Baseline Surface Radiation Measurement) ground based measurements and significant lower as the CM-SAF (Climate Monitoring Satellite Application Facility) target accuracy of 10 W/m2. The mean absolute difference between monthly means of ground measurements and satellite based solar surface irradiance is 5 W/m2 with a mean bias deviation of − 1 W/m2 and a RMSD (Root Mean Square Deviation) of 5.4 W/m2 for the investigated European sites. The results for the investigated African sites obtained by comparing instantaneous values are also encouraging. The mean absolute difference is with 2.8% even lower as for the European sites being 3.9%, but the mean bias deviation is with − 1.1% slightly higher as for the European sites, being 0.8%. Validation results over the ocean in the Mediterranean Sea using shipboard data complete the validation. The mean bias is − 3.6 W/m2 and 2.3% respectively. The slightly higher mean bias deviation over ocean is at least partly resulting from inherent differences due to the movement of the ship (shadowing, allocation of satellite pixel). The validation results demonstrate that the high accuracy of the surface solar irradiance is given in different climate regions. The discussed method has also the potential to improve the treatment of radiation processes in climate and Numerical Weather Prediction (NWP) models, because of the high accuracy combined with a high computing speed. 相似文献
8.
This study tested the potentiality of dielectric analysis (DEA) for determining the reaction performance of light-curing dental
resins. The influence of polymerisation conditions and material properties on the ion viscosity were investigated within a
current field. The restoratives were light-cured for 20, 40 or 60 s in a layer thickness between 1, 2 , or 3 mm with a varying
distance between curing light and specimen of 1, 3 or 5 mm. The tests were performed at 25°C/37°C with different polymerisation
modes. Nine restoratives (two composites and their derivate flowables, two ormocers, one compomer, one nano-filled composite
and one siloran) were investigated. The ion-viscosity-time graph was analysed to characterize reaction velocity and polymerisation
conversion. The slope of the ion viscosity decreased with increasing distance between polymerisation light and specimen. The
time of exposure affected the affinity and the conversion, with a polymerisation maximum at 40 s. A relation between thickness
and reaction time and between polymerisation modus and conversion/velocity was found. The temperature influenced the reaction
affinity. Different materials showed an individual curing performance. DEA-monitoring of the ion viscosity gives principal
insight in the polymerisation reaction of light curing materials. Further investigations are necessary for identifying the
relation between ion viscosity and polymerisation. 相似文献
9.
10.
The development of new catalysts for the oxidation of chemical compounds with oxygen as cheap and environmentally oxidant is an important topic of the current research. Due to the risk of the formation of potentially explosive gas mixtures aerobic oxidation reactions have to be performed with consideration of the explosion prevention. A safety concept for aerobic oxidation reactions and the construction of an experimental plant is presented. The oxidative cleavage of methyl 9,10‐dihydroxystearate to azelaic acid methyl ester and pelargonic acid was investigated as a model reaction. 相似文献