Search results: Found 33

Listing 1 - 10 of 33 << page
of 4
>>
Sort by
Educational Reception in Rotterdam and Barcelona: Policies, Practices and Gaps

Author:
ISBN: 9789089646446 Year: DOI: 10.26530/OAPEN_503423 Language: Undetermined
Publisher: Amsterdam University Press
Subject: History --- Migration
Added to DOAB on : 2014-10-23 11:01:07
License:

Loading...
Export citation

Choose an application

Abstract

The reception of newcomer youngsters by schools constitutes a policy issue in Europe already for decades. This book deals with how practitioners in Rotterdam and Barcelona apply existing policies for the reception of immigrant students, the dilemmas they face and the strategies they design as a response. Using a combination of discursive, organizational, and ethnographic research techniques, the author studies to what extent practices conform to policies, and to what extent they diverge from them in basic principles. This book analyzes the influence of institutional frameworks on the practices of policy implementers by comparing Netherlands and Spain -specifically Barcelona and Rotterdam-, two cases which are very different in terms of their national policies of integration, their educational systems and their programs for educational reception. Much can be learned over the reception practices of secondary schools, but above all over how policy gaps work, and the common and specific features that they present across different countries. In short, this is an indispensable reading for scholars, policymakers and practitioners alike, which offers new insights about the policy-practice gap and the role of policy practitioners in it.

Hemichannels; from the molecule to the function

Authors: ---
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889194674 Year: Pages: 122 DOI: 10.3389/978-2-88919-467-4 Language: English
Publisher: Frontiers Media SA
Subject: Physiology --- Science (General)
Added to DOAB on : 2016-03-10 08:14:32
License:

Loading...
Export citation

Choose an application

Abstract

Coordinated cell interactions are required to accomplish several complex and dynamic tasks observed in several tissues. Cell function may be coordinated by cell-to-cell communication through gap junctions channels (GJCs). These channels are formed by the serial docking of two hemichannels, which in turn are formed by six protein subunits called connexins (Cxs). It is well known that GJCs are involved in several functions, such as intercellular propagation of calcium waves, spread of electrotonic potentialsand spatial buffering of ions and metabolites. On the other hand, undocked hemichannels, which are not forming GJCs, can also serve other functions as “free hemichannels”. Currently, it is recognized that undocked hemichannels may have functional relevance in cell physiology allowing diffusional exchange of ions and small molecules between intra- and extra-cellular compartments. Additionally, another family of proteins calls pannexins (Panx) also forms functional hemichannels at the plasma membrane. Recently, Panxhemichannels have been involved in both pathological and physiological processes. Controlled hemichannel opening allows the release of small signaling molecules including ATP, glutamate, NAD+, adenosine, cyclic nucleotides, PGE2. They also allow uptake of relevant signaling molecules (e.g., cADPR) and metabolites (e.g., glucose). Additionally, a growing body of evidence shows that hemichannels are involved in important processes, such glucose detection in tanicytes, activation of the inflammasome, memory consolidation in the basolateral amygdala, potentiation of muscle contraction and release of nitric oxide from endothelial cells, among others. However, hemichannels can also play an important role in the homeostatic imbalance observed in diverse chronic diseases. In fact, massive and/or uncontrolled hemichannel opening induces or accelerates cell death in several pathological conditions including Charcot-Marie-Tooth disease, ischemia, oculodentodigital dysplasia, hydrotic ectodermic dysplasia, inflammatory responses, and deafness. Hemichannel-mediated cell death is due mainly to an entry of Ca+2. The latter activates proteases, nucleases and lipases, causing irreversible cell damage. An increasing amount of evidence demonstrates that blockade of uncontrolled hemichannel opening greatly reduces the cellular damage observed in several chronic diseases models. Therefore, Cx and Panx-hemichannels appear as promising drug targets for clinical treatment of human chronic diseases. Therefore, pharmacological tools are urgently needed to further elucidate hemichannels functions and to validate them as drug targets for the development of novel therapies for connexin-based diseases. Thus, understanding the role of Cx and Panx-hemichannels under physiological conditions and recognizing the molecular mechanisms controlling them, may provide us with a better picture of the hemichannels participation in some diseases and of the signals underlying their malfunctioning.

Interplay of Connexins and Pannexins in Tissue Function and Disease

Authors: ---
ISBN: 9783038973928 9783038973935 Year: Pages: 380 DOI: 10.3390/books978-3-03897-393-5 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Biology
Added to DOAB on : 2018-11-30 12:13:56
License:

Loading...
Export citation

Choose an application

Abstract

This Special Issue is related to the 18th biannual International Gap Junction Conference (IGJC2017), which has been held at the Crowne Plaza Hotel, Glasgow and hosted by Glasgow Caledonian University, 29 July–3 August, 2017. This Special Issue, entitled “Interplay of Connexins and Pannexins in Tissue Function and Disease”, focuses on six key state-of-the-art reviews, written by leads in the field on cutting edge topics and the latest developments in clinical trials in diverse organ systems. A further 14 original articles contributed by delegates attending the meeting are also included and celebrate 50 years of Gap Junction Research.Topics: Connexins and Pannexins:•Trafficking, Assembly, Gating, and Protein–Protein Interactions•Roles in the Cardiovascular System•Roles in Tumorigenesis•Roles in Epithelial Tissue and Wound Healing •Connexin Therapy Translated to Clinic

Monetary Policy and Unemployment

Author:
Book Series: Routledge International Studies in Money and Banking ISBN: 9780203329580 9780415700870 9780415650250 9781135993818 9781135993801 9781135993764 Year: DOI: 10.4324/9780203329580 Language: English
Publisher: Taylor & Francis
Subject: Business and Management --- Economics
Added to DOAB on : 2019-11-08 11:21:17
License:

Loading...
Export citation

Choose an application

Abstract

This book pulls together papers presented at a conference in honour of the 1981 Nobel Prize Winner for Economic Science, the late James Tobin. Among the contributors are Olivier Blanchard, Edmund Phelps, Charles Goodhart and Marco Buti. One of the main aims of the conference was to discuss what potential role monetary policy has on economic activity and unemployment reduction in three key currency zones - the United States, European Union and Japan.

Keywords

output --- gap --- real --- interest --- rate --- taylor --- rule --- central --- bank --- nominal

La question des barrages et du GAP dans le Sud-Est anatolien

Author:
ISBN: 9782906053809 9782362450372 Year: Language: French
Publisher: Institut français d’études anatoliennes
Added to DOAB on : 2017-05-17 15:07:11
License: OpenEdition licence for Books

Mind the gap! Gap junction channels and their importance in pathogenesis

Authors: --- ---
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889192380 Year: Pages: 252 DOI: 10.3389/978-2-88919-238-0 Language: English
Publisher: Frontiers Media SA
Subject: Neurology --- Medicine (General) --- Therapeutics --- Science (General)
Added to DOAB on : 2015-11-16 15:44:59
License:

Loading...
Export citation

Choose an application

Abstract

"Cells live together, but die singly", this sentence wrote the German physiologist Theodor Engelmann in 1875 and although he had no particular knowledge of gap junction channels (their structure was discovered around 100 years later) he described their functions very well: gap junction channels are essential for intercellular communication and crucial for the development of tissue and organs. But besides providing an opportunity for cells to communicate gap junction channels might also prevent intercellular communication by channel closure thereby preserving the surrounding healthy tissue in case of cellular necrosis. According to today’s understanding gap junction channels play an important role during embryonic development, during growth, wound healing and cell differentiation and are also involved in the process of learning. In the past decades most intensive research was done not only to unravel the physiological role of gap junction channels but also to extend our knowledge of the contribution of these channels in pathogenesis. A new frontier emerges in the field "pharmacology of gap junctions" with the aim to control growth, differentiation, or electrical coupling via targeting gap junction channels pharmacologically. As we know today disturbances in gap junction synthesis, assembly and cellular distribution may account for various organic disorders from most different medical fields, such as the Charcot-Marie-Tooth neuropathy, epilepsy, Chagas-disease, Naxos-syndrome, congenital cardiac malformations, arrhythmias, cancer and as a very common disease in industrial countries atherosclerosis. Point mutations in gap junction channels have been found to cause hereditary diseases like the congenital deafness or the Charcot-Marie-Tooth neuropathy but the exact molecular mechanisms of gap junction malfunction from most of the mentioned illnesses are not fully understood. Moreover, in the last few years research has expanded on the role and function of connexin hemichannels and on a relatively new field the pannexins. The purpose of this volume is to give a comprehensive overview of the involvement of gap junction channels, hemichannels and pannexins on pathogenesis of inborn and acquired diseases and on emerging pharmacological strategies to target these channels. We welcome our colleagues to contribute their findings on the influence of gap junctions on pathogenesis and to unravel the secrets of intercellular communication. Take the lid off!

Inhibitory Function in Auditory Processing

Authors: --- ---
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889196678 Year: Pages: 231 DOI: 10.3389/978-2-88919-667-8 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Neurology
Added to DOAB on : 2016-08-16 10:34:25
License:

Loading...
Export citation

Choose an application

Abstract

There seems little doubt that from the earliest evolutionary beginnings, inhibition has been a fundamental feature of neuronal circuits - even the simplest life forms sense and interact with their environment, orienting or approaching positive stimuli while avoiding aversive stimuli. This requires internal signals that both drive and suppress behavior. Traditional descriptions of inhibition sometimes limit its role to the suppression of action potential generation. This view fails to capture the vast breadth of inhibitory function now known to exist in neural circuits. A modern perspective on inhibitory signaling comprises a multitude of mechanisms. For example, inhibition can act via a shunting mechanism to speed the membrane time constant and reduce synaptic integration time. It can act via G-protein coupled receptors to initiate second messenger cascades that influence synaptic strength. Inhibition contributes to rhythm generation and can even activate ion channels that mediate inward currents to drive action potential generation. Inhibition also appears to play a role in shaping the properties of neural circuitry over longer time scales. Experience-dependent synaptic plasticity in developing and mature neural circuits underlies behavioral memory and has been intensively studied over the past decade. At excitatory synapses, adjustments of synaptic efficacy are regulated predominantly by changes in the number and function of postsynaptic glutamate receptors. There is, however, increasing evidence for inhibitory modulation of target neuron excitability playing key roles in experience-dependent plasticity. One reason for our limited knowledge about plasticity at inhibitory synapses is that in most circuits, neurons receive convergent inputs from disparate sources. This problem can be overcome by investigating inhibitory circuits in a system with well-defined inhibitory nuclei and projections, each with a known computational function. Compared to other sensory systems, the auditory system has evolved a large number of subthalamic nuclei each devoted to processing distinct features of sound stimuli. This information once extracted is then re-assembled to form the percept the acoustic world around us. The well-understood function of many of these auditory nuclei has enhanced our understanding of inhibition's role in shaping their responses from easily distinguished inhibitory inputs. In particular, neurons devoted to processing the location of sound sources receive a complement of discrete inputs for which in vivo activity and function are well understood. Investigation of these areas has led to significant advances in understanding the development, physiology, and mechanistic underpinnings of inhibition that apply broadly to neuroscience. In this series of papers, we provide an authoritative resource for those interested in exploring the variety of inhibitory circuits and their function in auditory processing. We present original research and focused reviews touching on development, plasticity, anatomy, and evolution of inhibitory circuitry. We hope our readers will find these papers valuable and inspirational to their own research endeavors.

Encoding and Navigating Linguistic Representations in Memory

Authors: --- ---
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889451326 Year: Pages: 766 DOI: 10.3389/978-2-88945-132-6 Language: English
Publisher: Frontiers Media SA
Subject: Psychology --- Science (General)
Added to DOAB on : 2017-07-06 13:27:36
License:

Loading...
Export citation

Choose an application

Abstract

Successful speaking and understanding requires mechanisms for reliably encoding structured linguistic representations in memory and for effectively accessing information in those representations later. Studying the time-course of real-time linguistic dependency formation provides a valuable tool for uncovering the cognitive and neural basis of these mechanisms. This volume draws together multiple perspectives on encoding and navigating structured linguistic representations, to highlight important empirical insights, and to identify key priorities for new research in this area.

Axial beanspruchte K-Knoten aus dünnwandigen Rechteckhohlprofilen

Author:
Book Series: Berichte zum Stahl- und Leichtbau / Karlsruher Institut für Technologie, Versuchsanstalt für Stahl, Holz und Steine, Stahl- und Leichtbau ISSN: 21987912 ISBN: 9783731501909 Year: Volume: 1 Pages: XVI, 208 p. DOI: 10.5445/KSP/1000039450 Language: GERMAN
Publisher: KIT Scientific Publishing
Subject: Technology (General)
Added to DOAB on : 2019-07-30 20:02:02
License:

Loading...
Export citation

Choose an application

Abstract

Many of the sections included in the technical delivery conditions can only be used s by an acceptance for individual cases due to the limited application range of rectangular hollow section joints. The presented design approach allows for the design of K joints with thin-walled chord sections and makes these sections accessible to design. Additionally, it enables the design of joints with small gaps.

Remodeling of cardiac passive electrical properties and susceptibility to ventricular and atrial arrhythmias

Author:
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889196470 Year: Pages: 141 DOI: 10.3389/978-2-88919-647-0 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Physiology
Added to DOAB on : 2016-08-16 10:34:25
License:

Loading...
Export citation

Choose an application

Abstract

The effective management of cardiac arrhythmias, either of atrial or of ventricular origin, remains a major challenge. Sudden cardiac death due to ventricular tachyarrhythmias remains the leading cause of death in industrialized countries while atrial fibrillation is the most common rhythm disorder; an arrhythmia that’s prevalence is increasing and accounts for nearly one quarter of ischemic stokes the elderly population. Yet, despite the enormity of the problem, effective therapeutic interventions remain elusive. In fact, several initially promising antiarrhythmic agents were found to increase rather than decrease mortality in patients recovering from myocardial infarction. The question then is what went wrong, why have these interventions proven to be so ineffective? An obvious answer is the drugs were designed to attack the wrong therapeutic target. Clearly, targeting single ion channels (using either isolated ion channels or single myocytes preparations) has proven to be less than effective. What then is the appropriate target? It is well established that cardiac electrical properties can vary substantially between single cells and intact preparations. One obvious example is the observation that action potential duration is much longer in isolated cells as compared to multi-cellular preparations or intact hearts. Due to the low electrical resistance between adjacent myocytes, the cells act in coordinated fashion producing “electrotonic interdependence” between neighboring cells. Myocardial infarction and/or acute ischemia provoke profound changes in the passive electrical properties of cardiac muscle. In particular, electrotonic uncoupling of the myocytes disrupts the coordinated activation and repolarization of cardiac tissue. The resulting compensatory changes in ionic currents decrease cardiac electrical stability increasing the risk for life-threatening changes in the cardiac rhythm. Thus, the electrical properties of myocardial cells must be considered as a unit rather than in isolation. It is the purpose of this Research Topic to evaluate the largely neglected relationship between changes in passive electrical properties of cardiac muscle and arrhythmia formation.

Listing 1 - 10 of 33 << page
of 4
>>
Sort by