Search results for "55"
showing 10 items of 2320 documents
Advancing stem cells: New therapeutic strategies for treating central nervous system disorders
2018
In this special issue, we explore new methods and knowledge to improve stem cell transplantation in diseases and conditions such as stroke, PD, and depression. Advancing the conventional idea regarding cell replacement in stem cell therapy, stem cells may also transfer healthy mitochondria to diseased ischemic neurons in stroke and improve the therapeutic time window of tissue plasminogen activator (tPA) in a conjunctive therapy for stroke, and human Wharton’s Jelly-derived mesenchymal stromal cells (hWJ-MSCs) may rely mainly on trophic factor secretion to induce neuroprotective effects. In addition, trophic factors such as neurotrophin-4/5 (NT-4/5) and glial cell line-derived neurotrophic …
Towards automatic calibration of 2-D flood propagation models
2010
Abstract. Hydraulic models for flood propagation description are an essential tool in many fields and are used, for example, for flood hazard and risk assessments, evaluation of flood control measures, etc. Nowadays there are many models of different complexity regarding the mathematical foundation and spatial dimensions available, and most of them are comparatively easy to operate due to sophisticated tools for model setup and control. However, the calibration of these models is still underdeveloped in contrast to other models like e.g. hydrological models or models used in ecosystem analysis. This has two primary reasons: first, lack of relevant data against which the models can be calibr…
Bunker Cave stalagmites: an archive for central European Holocene climate variability
2012
Holocene climate was characterised by variability on multi-centennial to multi-decadal time scales. In central Europe, these fluctuations were most pronounced during winter. Here we present a record of past winter climate variability for the last 10.8 ka based on four speleothems from Bunker Cave, western Germany. Due to its central European location, the cave site is particularly well suited to record changes in precipitation and temperature in response to changes in the North Atlantic realm. We present high-resolution records of &delta;<sup>18</sup>O, &delta;<sup>13</sup>C values and Mg/Ca ratios. Changes in the Mg/Ca ratio are attributed to past meteoric p…
Simulating stress-dependent fluid flow in a fractured core sample using real-time X-ray CT data
2016
Various geoscientific applications require a fast prediction of fracture permeability for an optimal workflow. Hence, the objective of the current study is to introduce and validate a practical method to characterize and approximate single flow in fractures under different stress conditions by using a core-flooding apparatus, in situ X-ray computed tomography (CT) scans and a finite-volume method solving the Navier–Stokes–Brinkman equations. The permeability of the fractured sandstone sample was measured stepwise during a loading–unloading cycle (0.7 to 22.1 MPa and back) to validate the numerical results. Simultaneously, the pressurized core sample was imaged with a medical X-ray CT scanne…
X-ray CT analyses, models and numerical simulations: a comparison with petrophysical analyses in an experimental CO2 study
2016
An essential part of the collaborative research project H2STORE (hydrogen to store), which is funded by the German government, was a comparison of various analytical methods for characterizing reservoir sandstones from different stratigraphic units. In this context Permian, Triassic and Tertiary reservoir sandstones were analysed. Rock core materials, provided by RWE Gasspeicher GmbH (Dortmund, Germany), GDF Suez E&P Deutschland GmbH (Lingen, Germany), E.ON Gas Storage GmbH (Essen, Germany) and RAG Rohöl-Aufsuchungs Aktiengesellschaft (Vienna, Austria), were processed by different laboratory techniques; thin sections were prepared, rock fragments were crushed and cubes of 1 cm edge leng…
The Launch of a New Scandinavian Journal of Work and Organizational Psychology
2016
Background Welcome to this new journal – the Scandinavian Journal of Work and Organizational Psychology. The field of Work and Organizational Psychology has a long and strong tradition in Scandinavia. Typical studies within this field have focused on work environment issues, such as psychosocial working conditions, meaningfulness and influence at work. The focus on intervention and evaluation of work and organizational initiatives – focusing on the improvement of working life – has also been important in this research tradition. In a European and global context, there are relevant and prestigious journals covering the research field, such as the European Journal of Work and Organizational P…
Evaluating Safety Systems for Machine Tools with Computer Numerical Control using Analytic Hierarchy Process
2019
Computer numerical control (CNC) machine tools are complex production systems with fully automatic machine parts. Nowadays, high feed rates and machining speeds are used during the machining process. Human operators are still needed to set-up the machine, load/unload workpieces and parts, load the machining code, and supervise the machining process. The operators work in an environment where automated high-speed motions occur, and consequently, CNC machine tools have to be equipped with safety systems. The approach presented in this paper was to evaluate the main safety systems of CNC machine tools based upon the analytic hierarchy process (AHP). The analyzed systems were divided into six m…
Los derechos sucesorios del viudo en Vizcaya y Ayala (II)
2012
Dentro de la pluralidad de legislaciones civiles que conviven en España, el modelo vasco se convierte en paradigma de la idea, defendida doctrinalmente, de que en aquellos sistemas en los que el régimen económico matrimonial es el de separación de bienes, suelen concederse amplios derechos sucesorios al viudo, mientras que, en aquellos que parten de un sistema de comunidad, los derechos mortis causa que se le conceden o no existen, o son mínimos, puesto que la protección a su posible situación de desvalimiento se obtiene ya a través del régimen económico matrimonial. Éste es el caso del País Vasco, donde rige un sistema legal de comunidad como es el de comunicación foral de bienes. La exist…
A Conceptual Framework for Using and Evaluating Web-Based Learning Resources in School Education
2010
Published version of an article from the journal:Journal of Information Technology Education. Also available from the publisher: http://www.jite.org/documents/Vol9/JITEv9p053-079Hadjerrouit743.pdf Web-based learning resources (WBLRs) have provided teachers with a wide range of new teachingexperiences that are not possible in traditional classroom. However, little research has beendone as to which approach to WBLRs is suitable to address issues that are pertinent to learning.This paper proposes a conceptual framework to explore the design and evaluation of WBLRs inschool education. The paper also examines the way in which the framework is used to evaluatestudents? and teachers? perceptions o…
The meaning of peer group mentoring in the university context
2019
Peer mentoring is commonly used for didactical and learning purposes. In this study we examine peer group mentoring in the university context. The aim is to promote understanding of peer group mentoring based on a meta-analysis of two primary studies: teacher students and teacher group tutors. As a result, three core categories were found: 1) Individual’s participation in the group, 2) Professional development with others and 3) Community enabling sharing and development. These were hierarchically organized and there are critical aspects placed in between the core categories. Professional and personal experiences intertwine to enhance participants’ self-understanding and professional develo…