bluuebunny/crossref_metadata_2025 huggingface dataset:
17‐β‐Estradiol‐mediated activation of extracellular‐signal regulated kinase, phosphatidylinositol 3‐kinase/protein kinase B‐Akt and N‐methyl‐d‐aspartate receptor phosphorylation in cortical synaptoneurosomes
Authors: Dominguez Reymundo , Liu Roulan , Baudry Michel
Published: January 2007

In addition to its well‐known activational mechanism, the steroid hormone 17‐β‐estradiol (E2) has been shown to rapidly activate various signal transduction pathways that could participate in estrogen‐mediated regulation of synaptic plasticity. Although the mechanisms underlying these effects are not clearly understood, it has been repeatedly suggested that they involve a plasma membrane receptor which has direct links to several intracellular signaling cascades. To further address the question of whether E2 acts directly at the synapse and through membrane‐bound receptors, we studied the effects of E2 and of ligands of estrogen receptors on various signaling pathways in cortical synaptoneurosomes. Our results demonstrate that E2 elicits N‐methyl‐d‐aspartate receptor phosphorylation and activates the extracellular signal‐regulated kinase and the phosphatidylinositol 3‐kinase/Akt signal transduction pathways in this cortical membrane preparation. Furthermore, we provide evidence for the presence of a membrane‐bound estrogen receptor responsible for these effects in cortical synaptoneurosomes. Our study demonstrates that E2 directly acts at cortical synapses, and that synaptoneurosomes provide a useful system to investigate the mechanisms by which E2 regulates synaptic transmission and plasticity.
The structure of human collapsin response mediator protein 2, a regulator of axonal growth
Authors: Stenmark Pål , Ogg Derek , Flodin Susanne , Flores Alex , Kotenyova Tetyana , Nyman Tomas , Nordlund Pär , Kursula Petri
Published: January 2007

Axonal growth cone guidance is a central process in nervous system development and repair. Collapsin response mediator protein 2 (CRMP‐2) is a neurite extension‐promoting neuronal cytosolic molecule involved in the signalling of growth inhibitory cues from external stimuli, such as semaphorin 3A and the myelin‐associated glycoprotein. We have determined the crystal structure of human tetrameric CRMP‐2, which is structurally related to the dihydropyriminidases; however, the active site is not conserved. The wealth of earlier functional mapping data for CRMP‐2 are discussed in light of the three‐dimensional structure of the protein. The differences in oligomerisation interfaces between CRMP‐1 and CRMP‐2 are used to model CRMP‐1/2 heterotetramers.
Stopover duration of Palearctic passerine migrants in the western Sahara – independent of fat stores?
Authors: SALEWSKI VOLKER , SCHAUB MICHAEL
Published: January 2007

Birds on migration spend much more time on stopover sites to refuel for the next migration step than aloft, but empirical data on stopover duration are rare, especially for Palearctic trans‐Sahara migrants whilst crossing the desert. Previous studies suggest that stopover duration of fat birds in oases is much shorter than that of lean birds. During 2003 and 2004 capture–recapture data of migrating passerines from two inland oases in spring and from one coastal site in autumn in Mauritania, West Africa, were analysed to test whether the probability of being a transient and the stopover duration depend on fuel stores at first capture. The application of capture–recapture models revealed that during autumn migration at the coast the proportion of transients (individuals that stop over only for 1 day) was relatively high (77–90%) in three out of four species investigated and stopover duration was short (1.9–4.6 days). In the inland oases in spring, transients were detected in only four out of 12 analyses. Stopover duration was longer than at the coast in autumn and surprisingly long in some species with durations of up to 30 days. Models taking into account the initial fat load of birds on the first capture occasion were, with one exception, never the most parsimonious ones. This indicates that the time spent after and before capture at the stopover site did not depend on the fat stores at first capture. Therefore, we cannot confirm the assumption that birds arriving at stopover sites in the desert with low fat loads stay longer than birds that arrive with high fat loads.
Photography in Pink Classrooms
Authors: Ashburn Liz
Published: January 2007

The teaching of photography provides many opportunities to attack the assumption of universal heterosexuality, which is central to our society, in order to provide space for other sexualities such as gay, lesbian, bisexual and transgender. This article is based on many years of lecturing in art schools and focuses on the classroom teaching of photography. It offers four perspectives for the expression of sexuality and possible change through the opening up of the curriculum to allow the inclusion of homosexual and queer art in the cultural capital of society; strategies to oppose heteronormativity; ways of treating students in the classroom in order to gain social justice in regard to sexual preference and finally the social benefits to all when heteronormativity is replaced with more equitable understandings, which could lead to a more inclusive community.
Sapphos to Baby Dykes: A Photo‐Essay
Authors: Lee Amelia ,   the young women of LIK:T
Published: January 2007

The LIK:T Young lesbian and Bisexual Women's Project have done a substantial piece of work looking at role models and aspirations of young lesbians and bisexual women through art.

The aim of the project was to try and break down isolation, and to raise the aspirations of young lesbian and bisexual (LB) women, as often as a group, LB women have a hidden history/herstory.

The work was done over a number of months, including a consultation event in Manchester with lesbian and bisexual women across the generations; a research trip to the Glasgow Women's Library (and their Lesbian Archive); and a number of pieces put together at other events around the country by our roving reporters/photographers.

The exhibit created includes six posters designed by the young women involved, and a photo collection of lesbian and bisexual women from across the generations, with accompanying interviews about their loves, lives and everything.
Experimental Investigation of Eclogite Rheology and Its Fabrics at High Temperature and Pressure
Authors: ZHANG J. , GREEN H. W.
Published: January 2007

Eclogite plays an important role in mantle convection and geodynamics in subduction zones. An improved understanding of processes in the deeper levels of subduction zones and collision belts requires information on eclogite rheology. However, the deformation processes and associated fabrics in eclogite are not well understood. Incompatible views of deformation mechanism have been proposed for both garnet and omphacite. We present here deformation behaviour of eclogite at temperatures of 1027–1427 °C, confining pressures of 2.5–3.5 GPa, and strain rates of 1 × 10−5 s−1 to 5 × 10−4 s−1. We obtained a power‐law creep for the high temperature and pressure deformation of a ‘dry’ eclogite (50 vol.% garnet, 40% omphacite and 10% quartz) with A = 103.3 ± 1.0, n = 3.5 ± 0.4, ΔE =403 ± 30 KJ mol−1 and ΔV = 27.2 cm3 mol−1. The two principal minerals of eclogite have greatly different strengths. Progressive increase of garnet results in a smooth increase in strength. Analysis by electron back‐scattered diffraction shows that: (1) garnet displays pole figures with near random distributions of misorientation angle under both dry and wet conditions; (2) omphacite shows pronounced lattice preferred orientations (LPOs), suggesting a dominant dislocation creep mechanism. Further investigation into the water effects on eclogite show: (3) water content does not influence the style of omphacite fabric but increases slightly the fabric strength; (4) grain boundary processes dominate the deformation of garnet under high water fugacity or high shear‐strain conditions, yielding a random LPO similar to that of non‐deforming garnet, despite the strong shape preferred orientation (SPO) observed. {110} [001] slip may dominate the deformation of rutile. Quartz displays complicated and inconsistent LPOs in eclogite. These results are remarkably similar to observations from deformed eclogites in nature.
Starting a Home Hemodialysis Program
Authors: Moran John , Kraus Michael
Published: January 2007

Home hemodialysis is not a new therapy; rather it is a therapy in which interest has been rekindled due to both the continually growing end‐stage renal disease population and concern about poor outcomes in patients on conventional thrice‐weekly in‐center dialysis. The practical issues to be considered when starting a home hemodialysis center are presented, including the choice of equipment, patient selection and training, home set‐up, dialysis prescription, and patient follow‐up. We outline the steps required to start a program that will be successful for patients, caretakers, and providers alike.
Is There More to Living Than Not Dying? A Reflection on Survival Studies in Dialysis
Authors: Bargman Joanne M.
Published: January 2007

The publication of the CHOICE study, which compared survival of US hemodialysis and peritoneal dialysis patients, has re‐opened the debate about the relative merits of the two dialysis modalities. The principal focus of the research and associated commentary, however, is about which modality is associated with the longest life expectancy. What appears to be missing, however, in the quagmire of propensity scores, comorbidity and confounding factors is that outcomes other than duration of survival must be addressed in discussions of the merits of renal replacement therapies. Home dialysis is very different from in‐center hemodialysis, and each therapy has advantages and disadvantages that will have different implications for each patient. Given that overall survival is comparable between home peritoneal dialysis and in‐center hemodialysis, we need to stop focusing so much on survival time and let the informed patient choose the modality.
Gene Polymorphism Association Studies in Dialysis: Vascular Access
Authors: Girndt Matthias , Heine Gunnar H. , Ulrich Christof , Köhler Hans ,   for the DialGene Consortium
Published: January 2007

Complications of the vascular access site for hemodialysis are a major cause of morbidity, suboptimal dialysis, and hospitalization. Vascular access for dialysis that is achieved by central venous catheters is associated with complications such as infection and thrombosis. Arteriovenous fistulas and grafts are also at risk for infectious complications. Further, proliferation of the venous wall with secondary thrombosis is a common pathophysiological process that leads to vascular access dysfunction. Genetic polymorphisms that contribute to vascular access failure are found among factors of the coagulation cascade, and host mediators that induce endothelial dysfunction as well as vessel wall proliferation. The two most common mutations of coagulation factors seem to influence the risk of central venous catheter and fistula thrombosis. Indeed, both the single nucleotide polymorphism of the factor V gene at amino acid position 506 (factor V Leiden mutation) and the prothrombin 20210 polymorphism have been associated with thrombotic complications of the vascular access. Among the endothelium‐directed factors, a polymorphism of the methylene tetrahydrofolate reductase gene coding for an enzyme that degrades the endothelium toxic product homocysteine, has been associated with fistula failure. While the angiotensin converting enzyme polymorphism does not seem to be associated with vascular access complications, polymorphisms of the profibrogenic cytokine transforming growth factor‐β1 are associated with the prognosis of native arteriovenous fistulae. The role of pro‐ and anti‐inflammatory cytokine gene polymorphisms as prognostic factors for vascular access is yet to be clearly defined.
Cerebral Cortical Gyrification: A Preliminary Investigation in Temporal Lobe Epilepsy
Authors: Ronan Lisa , Murphy Kevin , Delanty Norman , Doherty Colin , Maguire Sinead , Scanlon Cathy , Fitzsimons Mary
Published: January 2007

Summary:  Purpose: To introduce a measure of global cortical folding in epilepsy by using stereology. Subtle developmental abnormalities associated with temporal lobe epilepsy may encompass brain morphologic changes such as an aberrant degree of cortical folding.

Methods: Stereologic methods of volume and surface‐area estimation were applied to in vivo MR brain‐image data of a cohort of 20 temporal lobe epilepsy (TLE) patients (10 men, 10 women), and 20 neurologically normal controls (10 men, 10 women). Indices of cerebral gyrification and cerebral atrophy were generated. The impact of side of seizure onset, age at onset, history of febrile seizures, presence or absence of lesions, and presence or absence of secondarily generalized seizures on cerebral gyrification was assessed.

Results: Although no significant group mean difference was found in the degree of cerebral gyrification between patients and controls, five of 10 of male patients had an abnormal gyrification when compared with male controls. One female patient had a significant change in gyrification compared with female controls. In general, patients with TLE demonstrated a significant degree of global cerebral atrophy compared with controls. Clinical factors were not demonstrated to affect significantly any of the quantitative parameters.

Conclusions: The results of this study suggest that an aberrant degree of global cerebral gyrification may occur in certain clinical groups of TLE patients. These findings have implications for general theories of developmental susceptibility in TLE.
Neocortical and Thalamic Spread of Amygdala Kindled Seizures
Authors: Blumenfeld Hal , Rivera Maritza , Vasquez J. Gabriel , Shah Akash , Ismail Dina , Enev Miro , Zaveri Hitten P.
Published: January 2007

Summary:  Purpose: Amygdala kindling is an epilepsy model involving long‐term network plasticity in the nervous system. In this model, repeated weak stimulation of the amygdala eventually leads to severe motor seizures. The mechanisms for worsening behavioral seizures, and the possible role of enhanced connectivity between the amygdala and other structures have not been thoroughly investigated.

Methods: We performed simultaneous field potential recordings from the amygdala, frontal cortex, and medial thalamus during kindling in rats. Seizures were analyzed for signal power compared with baseline and for correlation between recording sites. Interictal signals were analyzed for changes in coherence between electrode contacts in kindled animals compared with sham kindled controls.

Results: We found that increased behavioral severity of seizures was related to increased seizure duration and to increased signal power in the frontal cortex and medial thalamus. Kindling was associated with increased connectivity between the amygdala and frontal cortex, based on increased amygdala–frontal signal correlation during seizures. In addition, during the interictal period, increased coherence was noted between amygdala and frontal contacts in kindled animals compared with controls.

Conclusions: We found evidence for increased connectivity between the amygdala and frontal cortex both during seizures and in the interictal period, as a result of kindling. Enhanced connections between limbic and neocortical circuits may be important for the development of epilepsy, as well as for normal long‐range network plasticity in the nervous system.
Clinical Correlates of Occipital Intermittent Rhythmic Delta Activity (OIRDA) in Children
Authors: Watemberg Nathan , Linder Ilan , Dabby Ron , Blumkin Lubov , Lerman‐Sagie Tally
Published: January 2007

Summary:  Purpose: The clinical significance of occipital intermittent rhythmic delta activity (OIRDA) on the electroencephalogram has not been fully established. Recent studies suggest that this pattern occurs almost exclusively in children and is probably of epileptic origin in most cases. We sought to characterize the electrographic features and clinical correlates of occipital intermittent rhythmic delta activity.

Methods: A review of 697 consecutive pediatric electroencephalograms detected occipital intermittent rhythmic delta activity in 24 studies. Mean patient age was 7.96 years.

Results: Recent convulsions and absence seizures constituted the main indications for the study. Concomitant, independent epileptiform activity was noted in half of the cases. This activity was focal in all but one case. Conversely, in most cases of absence seizures, epileptiform activity intermixed with occipital intermittent rhythmic delta activity. Furthermore, the frequency of the occipital rhythmic discharges in studies of children with absences was generally faster (3–4 Hz) than in localization‐related epilepsy (2–3 Hz). Most patients were awake when occipital intermittent rhythmic delta activity occurred. Chronic encephalopathy was seen in one child only. Analysis of neuroimaging studies in eight cases revealed no structural pathology associated with occipital intermittent rhythmic delta activity.

Conclusions: Occipital intermittent rhythmic delta activity is probably an epileptiform pattern, although it is noted occasionally in encephalopathic children. Its electrographic characteristics appear to differ between localization‐related epilepsy and primary generalized epilepsy, particularly absence seizures.
Slow Repetitive TMS for Drug‐resistant Epilepsy: Clinical and EEG Findings of a Placebo‐controlled Trial
Authors: Cantello Roberto , Rossi Simone , Varrasi Claudia , Ulivelli Monica , Civardi Carlo , Bartalini Sabina , Vatti Giampaolo , Cincotta Massimo , Borgheresi Alessandra , Zaccara Gaetano , Quartarone Angelo , Crupi Domenica , Laganà Angela , Inghilleri Maurizio , Giallonardo Anna Teresa , Berardelli Alfredo , Pacifici Loredana , Ferreri Florinda , Tombini Mario , Gilio Francesca , Quarato Pierpaolo , Conte Antonella , Manganotti Paolo , Bongiovanni Liugi Giuseppe , Monaco Francesco , Ferrante Daniela , Rossini Paolo Maria
Published: January 2007

Summary:  Purpose: To assess the effectiveness of slow repetitive transcranial magnetic stimulation (rTMS) as an adjunctive treatment for drug‐resistant epilepsy.

Methods: Forty‐three patients with drug‐resistant epilepsy from eight Italian Centers underwent a randomized, double‐blind, sham‐controlled, crossover study on the clinical and EEG effects of slow rTMS. The stimulus frequency was 0.3 Hz. One thousand stimuli per day were given at the resting motor threshold intensity for 5 consecutive days, with a round coil at the vertex.

Results:“Active” rTMS was no better than placebo for seizure reduction. However, it decreased interictal EEG epileptiform abnormalities significantly (p < 0.05) in one‐third of the patients, which supports a detectable biologic effect. No correlation linked the rTMS effects on seizure frequency to syndrome or anatomic classification, seizure type, EEG changes, or resting motor threshold (an index of motor cortex excitability).

Conclusions: Although the antiepileptic action was not significant (p > 0.05), the individual EEG reactivity to “active” rTMS may be encouraging for the development of more‐powerful, noninvasive neuromodulatory strategies.
Seizure Outcome after Resection of Supratentorial Cavernous Malformations: A Study of 168 Patients
Authors: Baumann Christian R. , Acciarri Nicola , Bertalanffy Helmut , Devinsky Orrin , Elger Christian E. , Lo Russo Giorgio , Cossu Massimo , Sure Uli , Singh Anuradha , Stefan Hermann , Hammen Tilo , Georgiadis Dimitrios , Baumgartner Ralf W. , Andermann Frederick , Siegel Adrian M.
Published: January 2007

Summary:  Purpose: The optimal management of cerebral cavernous malformations (CCMs) with epileptic seizures is still a matter of debate. The aim of our study was to examine seizure outcome in the largest published series of surgically treated patients with epilepsy due to a supratentorial CCM, and to define predictors for good surgical outcome.

Methods: We retrospectively studied 168 consecutive patients with a single supratentorial CCM and symptomatic epilepsy in a multicenter study. Pre‐ and postoperative clinical examinations, age at epilepsy onset, age at operation, type of symptoms due to the CCM (seizures, headache, hemorrhage, focal deficits), type and frequency of epileptic seizures, and the localization and size of the CCM were assessed. Seizure outcome was determined in the first, second, and third postoperative years.

Results: The CCM was completely resected in all patients. More than two thirds of the patients were classified as seizure free in the first 3 postoperative years. Predictors for good seizure outcome were age older than 30 years at the time of surgery, mesiotemporal CCM localization, CCM size <1.5 cm, and the absence of secondarily generalized seizures. No mortality occurred in our series, but only mild postoperative neurologic deficits in 12 (7%) patients.

Conclusions: Considering the natural history of CCMs, the favorable neurologic and seizure outcome, surgical resection of CCMs should be considered in all patients with supratentorial CCMs and concomitant epilepsy, irrespective of the presence or absence of predictors for a favorable seizure outcome.
Delegation, Committees, and Managers
Authors: Wernerfelt Birger
Published: January 2007

Attempts to economize on decision‐making time imply that groups of peers may delegate authority to a small committee of managers even though this means that the information and preferences of the uninvolved players are neglected. Decisions are more likely to be delegated to players with better information and more representative preferences. The possibility of ex post protests may force managers to take the preferences of others into account but may also give them incentives to ignore their private information. The argument may explain employees' willingness to let bosses decide, and thus throw some light on the theory of the firm.
Entrepreneurs and the Process of Obtaining Resources
Authors: Hellmann Thomas
Published: January 2007

This paper examines the process of how entrepreneurs assemble resources. In the model, the entrepreneur's challenge is to convince two complementary resource providers to commit their resources to a new venture. Before committing their resources, one of them needs to perform a costly evaluation. The entrepreneur has a problem with getting sufficient attention, because each provider has an incentive to wait and free‐ride on the other's evaluation. For some parameters the entrepreneur solicits both partners with equal intensity (“knocking on every door”); for others, the entrepreneur always solicits the same partner (“pestering”). For many but not all parameter ranges, the process of assembling resources takes too much time relative to what is socially efficient. The model thus explores what factors facilitate or hinder the creation of new firms.
Why people do not take their psychotropic drugs as prescribed: results of the 2000 National Psychiatric Morbidity Survey
Authors: Cooper C. , Bebbington P. , King M. , Brugha T. , Meltzer H. , Bhugra D. , Jenkins R.
Published: January 2007

Objective:  We examined the prevalence and determinants of the reasons given for non‐adherence to psychiatric medication in a representative community survey.

Method:  We used data for all participants taking oral psychotropic medication (n = 634) from the 2000 British Survey of National Psychiatric Morbidity.

Results:  Of participants interviewed, 217 (34.2%) reported incomplete adherence to their psychiatric medication. Reasons given included forgetting, losing, running out (37.4%); thinking medication unnecessary (24.6%); reluctance to take drugs (18.9%) and side‐effects (14.2%). Those giving forgetfulness or side‐effects as reasons were younger. Side‐effects were reported more frequently by people with a lower IQ or with psychosis. Those taking Selective Serotonin Reuptake Inhibitors were more likely to forget to take their medication.

Conclusion:  Two‐fifths of people reported that missing their medication was a decision taken because they did not want it or think it necessary. Side‐effects are a relatively uncommon reason for under‐medication. Our results have implications for interventions to assist adherence.
Mental distress and quality of life in the hard of hearing
Authors: Fellinger J. , Holzinger D. , Gerich J. , Goldberg D.
Published: January 2007

Objective:  This study aims to compare levels of psychological distress and the quality of life in the hard of hearing with levels reported by the signing deaf, and the hearing population.

Method:  A total of 373 members of the Hard of Hearing Association completed the brief WHO's Quality of Life, 12‐item General Health Questionnaire and Brief Symptom Inventory, and provided details about their initial and current deafness.

Results:  The hard of hearing have worse social relationships than the signing deaf, and are disadvantaged relative to the hearing in all areas measured. Quality of life is related to the level of satisfaction with the hearing achieved by hearing aids.

Conclusion:  General psychiatrists need to be aware that patients who are hard of hearing may be even more isolated than deaf people in a signing community. Hard of hearing patients with unsatisfactory hearing aids can be greatly assisted by cochlear implants.
Religious Views in Hans Christian Andersen's Works – and their Literary Implications
Authors: Mylius Johan de
Published: January 2007

Since Hans Christian Andersen has been admitted to the latest official hymn book in Denmark (2003) with two hymns, one might on this basis argue that he is no doubt a true Christian author. But although religion is essential to his life and works, his Christianity has often been questioned. A closer look at poems and stories by Andersen reveals a view of death as a moment of exclusiveness, intensity and enlightenment very similar to experiences known from mystic literature, but in his case connected with an idea of the soul as basically immortal and as being on an eternal journey, even qualifying and developing through and after death. This view of life and death and an ongoing life after death leads to a literary practice that dissolves the given epic structures and replaces them with musical and lyrical highlighting of the momentary experience.
Représentation et hiatus modianesques : lecture interstitielle
Authors: Barnett Richard‐Laurent
Published: January 2007

La mise en spectacle de la fiction et de ces mécanismes aurait chez Modiano une fonction moins de contestation ou de perturbation (comme dirait Ricardou) que de support pour la fiction que les moyens de mis en spectacle aident à instaurer. En dévoilant le processus scriptural, la thématisation du vide et les procédés de la réduplication servent à expliciter 1’entreprise littéraire tout en faisant sentir sa précarité. Suite d'événements qui n'ont ni début ni fin, actants qui n'existent qu'en assumant une autre identité (vivant leurs fantasmes à travers les êtres du passé dont ils racontent/inventent le vécu), fragmentation du récit et aussi des personnages qu'on ne saisit que par bribes à des moments séparés dans le temps et dans 1’espace, lacunes narratives que le lecteur se doit de combler lui‐même tant bien que mal, 1’ensemble de ces composantes de 1’univers romanesque de Modiano fait invariablement échec à toute composition linéaire et translucide reflétant un ordre rassurant et connu. L'absence d'un métatexte (evident) qui donnerait un sens au texte modianesque souligne 1’aspect problématique non seulement de cette oeuvre mais de toute entreprise littéraire moderne.
Intertextuelle Markierungen
Authors: Schlosser Jan T.
Published: January 2007

Der bislang kaum erhellte Dialog Martin Walsers mit Heinrich von Kleist lässt sich vor allem an dem Roman Finks Krieg ablesen, in dem die Auseinandersetzung Walsers mit Kleist als eine intendierte intertextuelle Strategie erkennbar wird, mit der er sich zugleich in die Kohlhaas‐Rezeption des späten 20. Jahrhunderts einschreibt und diese um eine nationale Identitätsvergewisserungen einkreisende Variante ergänzt. Die engmaschige – teilweise auch auf eine gebildete nationalkonservative Lesergruppe abzielende – Bezugnahme auf Michael Kohlhaas lässt sich anhand zahlreicher intertextueller Markierungen dokumentieren, die sowohl um die Übernahme von Figurennamen und ‐konstellationen, von Zitatcharakter aufweisenden Passagen und Schlüsselbegriffen wie um das produktive Aufgreifen zentraler Themen‐ und Motivkomplexe zentriert sind. Als Bedeutungselement eines neuen Textganzen gewinnt Finks Krieg insofern Modellcharakter, als der Roman einen wichtigen Beitrag zur präzisen Definition eines „engen“, nicht‐universellen Intertextualitätsbegriffs abgibt.
Cells from bone marrow that evolve into oral tissues and their clinical applications
Authors: Maria OM , Khosravi R , Mezey E , Tran SD
Published: January 2007

There are two major well‐characterized populations of post‐natal (adult) stem cells in bone marrow: hematopoietic stem cells which give rise to blood cells of all lineages, and mesenchymal stem cells which give rise to osteoblasts, adipocytes, and fibroblasts. For the past 50 years, strict rules were taught governing developmental biology. However, recently, numerous studies have emerged from researchers in different fields suggesting the unthinkable – that stem cells isolated from a variety of organs are capable of ignoring their cell lineage boundaries and exhibiting more plasticity in their fates. Plasticity is defined as the ability of post‐natal (tissue‐specific adult) stem cells to differentiate into mature and functional cells of the same or of a different germ layer of origin. There are reports that bone marrow stem cells can evolve into cells of all dermal lineages, such as hepatocytes, skeletal myocytes, cardiomyocytes, neural, endothelial, epithelial, and even endocrine cells. These findings promise significant therapeutic implications for regenerative medicine. This article will review recent reports of bone marrow cells that have the ability to evolve or differentiate into oral and craniofacial tissues, such as the periodontal ligament, alveolar bone, condyle, tooth, bone around dental and facial implants, and oral mucosa.
Analysis of Karst Aquifer Spring Flows with a Gray System Decomposition Model
Authors: Hao Yonghong , Yeh Tian‐Chyi J. , Wang Yanrong , Zhao Ying
Published: January 2007

There are ∼470,000 km2 of karst aquifers that feed many large springs in North China. Turbulent flow often exists in these karst aquifers, which means that the classical ground water model based on Darcy’s law cannot be applied here. Ground water data are rare for these aquifers. As a consequence, it is difficult to quantitatively investigate ground water flow in these karst systems. The purpose of this study is to develop a parsimonious model that predicts karst spring discharge using gray system theory. In this theory, a white color denotes a system that is completely characterized and a black color represents a system that is totally unknown. A gray system thus describes a complex system whose characteristics are only partially known or known with uncertainty. Using this theory, we investigated the karst spring discharge time series over different time scales. First, we identified three specific components of spring discharge: the long‐term trend, periodic variation, and random fluctuation. We then used the gray system model to simulate the long‐term trend and obtain periodic variation and random fluctuation components. Subsequently, we developed a predictive model for karst spring discharge. Application of the model to Liulin Springs, a representative example of karst springs in northern China, shows that the model performs well. The predicted results suggest that the Liulin Springs discharge will likely decrease over time, with small fluctuations.
Characterization of a Multilayer Aquifer Using Open Well Dilution Tests
Authors: West L. Jared , Odling Noelle E.
Published: January 2007

An approach to characterization of multilayer aquifer systems using open well borehole dilution is described. The approach involves measuring observation well flow velocities while a nearby extraction well is pumped by introducing a saline tracer into observation wells and collecting dilution vs. depth profiles. Inspection of tracer profile evolution allows discrete permeable layers within the aquifer to be identified. Dilution profiles for well sections between permeable layers are then converted into vertical borehole flow velocities and their evolution, using an analytic solution to the advection‐dispersion equation applied to borehole flow. The dilution approach is potentially able to measure much smaller flow velocities that would be detectable using flowmeters. Vertical flow velocity data from the observation wells are then matched to those generated using a hydraulic model of the aquifer system, “shorted” by the observation wells, to yield the hydraulic properties of the constituent layers. Observation well flow monitoring of pumping tests represents a cost‐effective alternative or preliminary approach to pump testing each layer of a multilayer aquifer system separately using straddle packers or screened wells and requires no prior knowledge of permeable layer depths and thicknesses. The modification described here, of using tracer dilution rather than flowmeter logging to obtain well flow velocities, allows the approach to be extended to greater well separations, thus characterizing a larger volume of the aquifer. An example of the application of this approach to a multilayer Chalk Aquifer in Yorkshire, Northeast England, is presented.
A Time of Quiet Activism: Research, Practice, and Policy in American Women's Higher Education, 1945–1965
Authors: Eisenmann Linda
Published: January 2007

This exploration of American women's post-World War II higher education begins with three stories. These narratives reflect issues women faced when, as educators, they tried to plan curricula and programs for female students, and when, as professionals, they tried to manage their own careers in an era that frequently sent mixed messages about women's roles and opportunities. They also reveal a quiet type of activism practiced by postwar women educators, an approach which often pales in comparison to the firmer efforts of postsuffrage and World War II activists, or to the lively and boisterous work of late-1960s feminists. However, I will argue that this more muted style, when combined with the era's predilection for individualized solutions to women's concerns, marks a particular postwar approach to advocacy that may be different from other eras but that suited the contextually complicated postwar period.
Indian Heart/White Man's Head: Native-American Teachers in Indian Schools, 1880–1930
Authors: Gere Anne Ruggles
Published: January 2007

Two teachers at Haskell who had a profound impact on my life were Ella Deloria and Ruth Muskrat Bronson. They stood apart from the others as far as I'm concerned. Ella Deloria was Standing Rock Sioux and a graduate of Columbia…. She taught girls' physical education and drama. Ruth Muskrat Bronson was Cherokee and a graduate of Mount Holyoke. She taught English. They both had such a wonderful sense of humor. They taught non-Indian subject matter but had a very strong respect for Indian culture, and they were clever enough to integrate it into the curriculum. They taught their students to have a healthy respect for themselves as individuals and a pride in their heritage. They taught us about Indian values and kept them alive in us. They respected and encouraged us to voice our opinions in and out of the classroom, and they had the ability to draw out our creativity. When Ruth would tell us to have pride in who we were, she'd say, “Indians are people too. Don't forget that.”
“From Moral Aristocracy to Christian Social Democracy”: The Transformation of Character Education in the Hi-Y, 1910–1940
Authors: Setran David P.
Published: January 2007

In the early twentieth century, many American educators pinned their hopes for a revitalized nation on the character education of “youth,” especially adolescent boys. Although the emphasis on student morality was far from novel—nineteenth-century common and secondary schools operated as bastions of Protestant republican virtue—new perceptions of moral decay, institutional failure, and general cultural anomie prompted a marked increase in urgency. Among the many agencies confronting this impending moral crisis, the Young Men's Christian Association (YMCA) had perhaps the most comprehensive program of regeneration for American youth, encompassing a carefully articulated system extending from boyhood to collegiate and employed young men. Despite this expansive role, historians have produced only cursory glimpses of this organization, neglecting in particular the YMCA's work in developing an extracurricular program of moral education in public high schools.
“Lady Teachers” and the Genteel Roots of Teacher Organization in Gilded Age Cities
Authors: Leroux Karen
Published: January 2007

May the work of the L.T.A. go on ever upward and onward-gaining ground year by year; so that in future it will have its voice in the community, not low & sweet-but clear and resonant showing power and strength; may it gain that strength by increased membership, held together by strong bonds of love.Let us then be up and doing,With a heart for any fate;Still achieving, still pursuingLearn to labor and to wait.1

Miss Ophelia S. Newell believed that teachers occupied a public office of unappreciated responsibility. As the secretary of the Lady Teachers' Association (LTA) in Boston, she penned these hopeful remarks as a coda to her 1875 annual report, borrowing the last stanza of a popular Henry Wadsworth Longfellow poem. For Newell and her fellow teachers, “learn to labor and to wait” underscored their steadfast commitment to the schools. They founded the association attempting to bring women teachers “nearer together in sympathy and friendship and also for a mutual benefit in debate and parliamentary rules.” Frustrated with being “accused of a lack of enthusiasm in our profession,” they hoped such criticism could “be remedied by an organization of this kind.” Honing their debating skills represented one of the women's objectives, but they aspired to do more than polish their chances for professional advancement.
The Proliferation of Case Method Teaching in American Law Schools: Mr. Langdell's Emblematic “Abomination,” 1890-1915
Authors: Kimball Bruce A.
Published: January 2007

Case method teaching was first introduced into American higher education in 1870 by Christopher C. Langdell (1826-1906) of Harvard Law School (HLS), where it became closely associated with—and emblematic of—a set of academic meritocratic reforms. Though regnant today, “the ultimate triumph of [Langdell's] system was not apparent” for many years. The vast majority of students, alumni, and law professors initially derided it as an “abomination,” and for two decades case method and the associated reforms were largely confined to Harvard. During the subsequent twenty-five years between 1890 and 1915, a national controversy ensued as to whether case method teaching—and the concomitant meritocratic reforms—would predominate in legal education and, ultimately, professional education in the United States.
Extensive Cortical Remyelination in Patients with Chronic Multiple Sclerosis
Authors: Albert Monika , Antel Jack , Brück Wolfgang , Stadelmann Christine
Published: January 2007

Recent studies revealed prominent cortical demyelination in patients with chronic multiple sclerosis (MS). Demyelination in white matter lesions is frequently accompanied by remyelination. This repair process, however, often remains incomplete and restricted to the lesion border. In the present study, we examined the frequency and extent of remyelination in cortical and white matter lesions in autopsy brain tissue of 33 patients with chronic MS. The majority of patients (29 of 33) harbored cortical demyelination. Remyelination of cortical lesions was identified light microscopically by the presence of thin and irregularly arranged myelin sheaths, and confirmed by electron microscopy. Extensive remyelination was found in 18%, remyelination restricted to the lesion border in 54%, and no remyelination in 28% of cortical lesions. A direct comparison of the extent of remyelination in white matter and cortical lesions of the same patients revealed that remyelination of cortical lesions was consistently more extensive. In addition, g‐ratios of fibers in areas of “normal appearing cortex” yielded values consistent with remyelination. Our data confirm the high prevalence of cortical demyelination in chronic MS and imply that the propensity to remyelinate is high in cortical MS lesions.
A NOVEL PT AND NPT MIXED IGBT HAVING A NEW n-BUFFER LAYER
Authors: ZHANG FEI , LUO SHUHUA , ZHANG LIANG , WANG WEI , YU WEN , LI CHENGFANG , SUN XIAOWEI
Published: January 2007

For the first time, a novel mixed insulated gate bipolar transistor (MIGBT) is proposed and verified by two-dimensional (2D) mixed device-circuit simulations. The structure of the proposed device is almost identical with that of the conventional IGBT, except for the buffer layer which is formed by employing the n+/n- structure, so that the trade-off relation between the conduction and switching losses is greatly improved and efficiently decoupled. Furthermore, the proposed device exhibits larger forward blocking voltage and positive temperature coefficient of the forward voltage drop, facilitating parallel integration.
Navigating Virtual Reality by Thought: What Is It Like?
Authors: Friedman Doron , Leeb Robert , Guger Christoph , Steed Anthony , Pfurtscheller Gert , Slater Mel
Published: January 2007

We have set up a brain-computer interface (BCI) to be used as an input device to a highly immersive virtual reality CAVE-like system. We have carried out two navigation experiments: three subjects were required to rotate in a virtual bar room by imagining left or right hand movement, and to walk along a single axis in a virtual street by imagining foot or hand movement. In this paper we focus on the subjective experience of navigating virtual reality “by thought,” and on the interrelations between BCI and presence.
Product Review: High Dynamic Range Displays
Authors: Ledda Patrick
Published: January 2007

In the natural world, the human eye is confronted with a wide range of colors and luminances. A surface lit by moonlight might have a luminance level of around 10−3 cd/m2, while surfaces lit during a sunny day could reach values larger than 105 cd/m2. A good quality CRT (cathode ray tube) or LCD (liquid crystal display) monitor is only able to achieve a maximum luminance of around 200 to 300 cd/m2 and a contrast ratio of not more than two orders of magnitude. In this context the contrast ratio or dynamic range is defined as the ratio of the highest to the lowest luminance. We call high dynamic range (HDR) images, those images (or scenes) in which the contrast ratio is larger than what a display can reproduce. In practice, any scene that contains some sort of light source and shadows is HDR. The main problem with HDR images is that they cannot be displayed, therefore although methods to create them do exist (by taking multiple photographs at different exposure times or using computer graphics 3D software for example) it is not possible to see both bright and dark areas simultaneously. (See Figure 1.) There is data that suggests that our eyes can see detail at any given adaptation level within a contrast of 10,000:1 between the brightest and darkest regions of a scene. Therefore an ideal display should be able to reproduce this range.

In this review, we present two high dynamic range displays developed by Brightside Technologies (formerly Sunnybrook Technologies) which are capable, for the first time, of linearly displaying high contrast images. These displays are of great use for both researchers in the vision/graphics/VR/medical fields as well as professionals in the VFX/gaming/architectural industry.
Synthetic Soundscapes with Natural Grains
Authors: Hoskinson Reynald , Pai Dinesh K
Published: January 2007

We present a technique to facilitate the creation of constantly changing, randomized audio streams from samples of source material. A core motivation is to make it easier to quickly create soundscapes for virtual environments and other scenarios where long streams of audio are used. While mostly in the background, these streams are vital for the creation of mood and realism in these types of applications. Our approach is to extract the component parts of sampled audio signals, and use them to resynthesize a continuous audio stream of indeterminate length. An automatic segmentation algorithm involving wavelets is used to split the input signal into syllable-like audio segments that we call “natural grains.” For each grain, a table of similarity between it and all the other grains is constructed. The grains are then output in a continuous stream, with the next grain being chosen from among those other grains which best follow from it. Using this sampling-resynthesis technique, we can construct an infinite number of variations on the original signal with a minimum amount of interaction. An interface for the manipulation and playback of several of these streams is provided to facilitate building complex audio environments, and is made available for online experimentation at www.cs.ubc.ca/labs/lci/naturalgrains/ .
Influence of Air-Conditioning Waste Heat on Air Temperature in Tokyo during Summer: Numerical Experiments Using an Urban Canopy Model Coupled with a Building Energy Model
Authors: Ohashi Yukitaka , Genchi Yutaka , Kondo Hiroaki , Kikegawa Yukihiro , Yoshikado Hiroshi , Hirano Yujiro
Published: January 2007

A coupled model consisting of a multilayer urban canopy model and a building energy analysis model has been developed to investigate the diurnal variations of outdoor air temperature in the office areas of Tokyo, Japan. Observations and numerical experiments have been performed for the two office areas in Tokyo. The main results obtained in this study are as follows. The coupled model has accurately simulated the air temperature for a weekday case in which released waste heat has been calculated from the energy consumption and cooling load in the buildings. The model has also simulated the air temperature for a holiday case. However, the waste heat from the buildings has little influence on the outdoor temperatures and can be neglected because of the low working activity in the buildings. The waste heat from the air conditioners has caused a temperature rise of 1°–2°C or more on weekdays in the Tokyo office areas. This heating promotes the heat-island phenomenon in Tokyo on weekdays. Thus, it is shown that the energy consumption process (mainly with air conditioning) in buildings should be included in the modeling of summertime air temperature on weekdays in urban areas.