860 resultados para shifting boundaries
Resumo:
We present a study of the evaporation dynamics of a substance undergoing a coarsening process. The system is modeled by the Cahn-Hilliard equation with absorbing boundaries. We have found that the dynamics, although of a diffusive nature, is much slower than the usual one without coarsening. Analytical and simulation results are in reasonable agreement.
Resumo:
Workgroup diversity can be conceptualized as variety, separation, or disparity. Thus, the proper operationalization of diversity depends on how a diversity dimension has been defined. Analytically, the minimal diversity must be obtained when there are no differences on an attribute among the members of a group, however maximal diversity has a different shape for each conceptualization of diversity. Previous work on diversity indexes indicated maximum values for variety (e.g., Blau"s index and Teachman"s index), separation (e.g., standard deviation and mean Euclidean distance), and disparity (e.g., coefficient of variation and the Gini coefficient of concentration), although these maximum values are not valid for all group characteristics (i.e., group size and group size parity) and attribute scales (i.e., number of categories). We demonstrate analytically appropriate upper boundaries for conditional diversity determined by some specific group characteristics, avoiding the bias related to absolute diversity. This will allow applied researchers to make better interpretations regarding the relationship between group diversity and group outcomes.
Resumo:
During the last two decades, endoscopic endonasal approach has completed the minimally invasive skull base surgery armamentarium. Endoscopic endonasal skull base surgery (EESBS) was initially developed in the field of pituitary adenomas, and gained an increasing place for the treatment of a wide variety of skull base pathologies, extending on the midline from crista galli process to the occipitocervical junction and laterally to the parasellar areas and petroclival apex. Until now, most studies are retrospective and lack sufficient methodological quality to confirm whether the endoscopic endonasal pituitary surgery has better results than the microsurgical trans-sphenoidal classical approach. The impressions of the expert teams show a trend toward better results for some pituitary adenomas with the endoscopic endonasal route, in terms of gross total resection rate and probably more comfortable postoperative course for the patient. Excepting intra- and suprasellar pituitary adenomas, EESBS seems useful for selected lesions extending onto the cavernous sinus and Meckel's cave but also for clival pathologies. Nevertheless, this infatuation toward endoscopic endonasal approaches has to be balanced with the critical issue of cerebrospinal fluid leaks, which constitutes actually the main limit of this approach. Through their experience and a review of the literature, the authors aim to present the state of the art of this approach as well as its limits.
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Appendix: List of species found in boundaries
Resumo:
The chapters collected in this volume are only a small sampling of the fruitwhich carne out ofthe Evil, Women and the Feminine conference held in Prague inMay 2010, hosted by the Inter-Disciplinary.Net. Our hopes are to bring togethersorne of the chapters, in expanded form, which seemed, without previous planning,to speak to each other during the conference and which, herein, more directiyengage with one another, opening up a space for dialogue and interaction. Whilewe have divided the work into four sections, they are not discrete boundaries but, we hope, they work together to elicit an interdisciplinary approach to ourunderstandings of women who push the limits of 'the feminine.'
Resumo:
The chapters collected in this volume are only a small sampling of the fruitwhich carne out ofthe Evil, Women and the Feminine conference held in Prague inMay 2010, hosted by the Inter-Disciplinary.Net. Our hopes are to bring togethersorne of the chapters, in expanded form, which seemed, without previous planning,to speak to each other during the conference and which, herein, more directiyengage with one another, opening up a space for dialogue and interaction. Whilewe have divided the work into four sections, they are not discrete boundaries but, we hope, they work together to elicit an interdisciplinary approach to ourunderstandings of women who push the limits of 'the feminine.'
Resumo:
In this paper, some steganalytic techniques designed to detect the existence of hidden messages using histogram shifting methods are presented. Firstly, some techniques to identify specific methods of histogram shifting, based on visible marks on the histogram or abnormal statistical distributions are suggested. Then, we present a general technique capable of detecting all histogram shifting techniques analyzed. This technique is based on the effect of histogram shifting methods on the "volatility" of the histogram of differences and the study of its reduction whenever new data are hidden.
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Peer-reviewed
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Inhibition of cholesterol export from late endosomes causes cellular cholesterol imbalance, including cholesterol depletion in the trans-Golgi network (TGN). Here, using Chinese hamster ovary (CHO) Niemann-Pick type C1 (NPC1) mutant cell lines and human NPC1 mutant fibroblasts, we show that altered cholesterol levels at the TGN/endosome boundaries trigger Syntaxin 6 (Stx6) accumulation into VAMP3, transferrin, and Rab11-positive recycling endosomes (REs). This increases Stx6/VAMP3 interaction and interferes with the recycling of αVβ3 and α5β1 integrins and cell migration, possibly in a Stx6-dependent manner. In NPC1 mutant cells, restoration of cholesterol levels in the TGN, but not inhibition of VAMP3, restores the steady-state localization of Stx6 in the TGN. Furthermore, elevation of RE cholesterol is associated with increased amounts of Stx6 in RE. Hence, the fine-tuning of cholesterol levels at the TGN-RE boundaries together with a subset of cholesterol-sensitive SNARE proteins may play a regulatory role in cell migration and invasion.
Resumo:
Tämän tutkimuksen tarkoituksena on tutkia sellu- ja paperiteollisuuden toimintojen luonnetta sekä miten yrityksen rajapinnat ovat muodostuneet ko. teollisuudenalalla. Tutkimus on eksploratiivinen ja luonteeltaan kvalitatiivinen. Tutkimuksen aineisto kerättiin yrityksissä tehdyillä teemahaastatteluilla. Sellu- ja paperitehtaan toimintojen analysoinnissa käytetään resurssiperusteista näkemystä ja transaktiokustannusteoriaa. Tutkimuksen yritysten rakennetta voidaan pitää varsin konservatiivisena. Teoreettinen kehys pystyi selittämään varsinaisen tuotannon järjestämistä varsin hyvin. Tukitoiminnoissa löytyi ristiriitoja teorian ja todellisuuden välillä. Tuotantotoiminnot kannattaa pitää yrityksen sisällä, koska ne täyttävät VRIN-attribuutit ja niihin liittyy korkeita transaktiokustannuksia. Suurin osa tukitoiminnoista voidaan luokitella triviaaleiksi. Joitain tukitoimintoja voidaan kuitenkin luokitella strategisesti tärkeiksi, ja voidaan päätellä, että ne pitäisi pitää yrityksen sisällä. Tässä suhteessa tulokset olivat kuitenkin ristiriitaisia, ja lisätutkimuksia tarvittaisiin lopullisten johtopäätösten tekemiseen.
Resumo:
Tutkielman tavoitteena oli selvittääcase -yrityksen resurssi- ja kyvykkyyspohjaa resurssiperustaisen näkemyksen mukaan, sekä yrityksen rajoja transaktiokustannusteorian mukaan. Tutkimusongelmia lähestyttiin kirjallisuuskatsauksella, puoli-strukturoiduilla teemahaastatteluilla, sekä kyselylomakkeilla. Tutkielman päätuloksiksi voidaan Tukea löydetty resurssikuilu, resurssien ja kyvykkyyksien tutkinta, sekä kyselylomakkeiden rakentaminen ja käyttö. Tutkielman paljastamasta kuilusta voidaan erottaa kolme päähaastetta; ikääntyvät sähköverkot, ikääntyvä henkilökunta ja liiketoimintaosaamisen puute. Lisäksi resurssien ja kyvykkyyksien tutkinta nosti esille organisaation rutiineja ja prosesseja, ja kyselylomakkeet osoittautuivat varsin toimiviksi tutkimuksen kontekstissa. Yhteenvetona voidaan todeta, että sähköverkkoliiketoiminta ja case yritys ovat suuren rakennemuutoksen alla, joka tuo mukanaan suuria haasteita myös lähitulevaisuudessa.