224 research outputs found
The first passage event for sums of dependent L\'evy processes with applications to insurance risk
For the sum process of a bivariate L\'evy process
with possibly dependent components, we derive a quintuple law describing the
first upwards passage event of over a fixed barrier, caused by a jump, by
the joint distribution of five quantities: the time relative to the time of the
previous maximum, the time of the previous maximum, the overshoot, the
undershoot and the undershoot of the previous maximum. The dependence between
the jumps of and is modeled by a L\'evy copula. We calculate these
quantities for some examples, where we pay particular attention to the
influence of the dependence structure. We apply our findings to the ruin event
of an insurance risk process.Comment: Published in at http://dx.doi.org/10.1214/09-AAP601 the Annals of
Applied Probability (http://www.imstat.org/aap/) by the Institute of
Mathematical Statistics (http://www.imstat.org
Non-traditonal students im Übergang zum Erwachsenwerden
Diese Forschungsarbeit handelt von dem Erwachsenwerden der non-traditional students. Ich versuche anhand der Analyse von drei Fallbeispielen herauszuarbeiten, wie sich Studierende mit verschlungenen, entstandardisierten Bildungsbiographien im Studium wahrnehmen und welche Handlungsbereiche an diesem Übergang erkennbar sind. Zudem beleuchte ich inwiefern das Phänomen des verzögerten Erwachenwerdens bei den non-tradtionals auftritt.
Der theoretische Bezug ist die subjektorientierte Übergangsforschung, die Theorien zur Postadoleszenz und zu Emerging Adulthood, sowie die Passungsprobleme der non traditionals am Übergang ins Studium. Methodisch bearbeitet werden diese Fragestellungen anhand des Narrativen Interviews nach Fritz Schütze und dessen Auswertungsverfahren der Prozesstrukturen des Lebenslaufs.
Im ersten Teil dieser Arbeit wird das Problem des Auseinandertretens der normalbiographischen Sichtweise von Adoleszenten und der subjektiven Wahrnehmung jener Betroffenen beleuchtet, sowie der Forschungsstand zu den non-traditonal students dargelegt.
In meiner Forschungsarbeit lege ich dar, dass das Erwachsenwerden kein objektivierbarer Übergang ist, sondern die Leistung eines individuellen Konstruktionsprozesses. Diese Übergangsprozesse vollziehen sich in der Regel krisenhaft, weshalb sie zur Aufgabe sozialpädagogischer Interventionen wurden. Die Forschungsergebnisse bestätigen die Theorie der Quarterlife Crisis und damit die Relevanz des sogenannte Übergangsmanagements, welches jene krisenhaften Übergänge begleiten soll. Zudem zeigt die Forschung die Bedeutung der sozialen Netzwerke für die Entwicklung einer selbstbewusste Handlungsakteure
Sabellaria nanella (Sabellariidae): from solitary subtidal to intertidal reef building worm at Monte Hermoso, Argentina (39°S, southwest Atlantic)
This contribution reports the first record of intertidal reefs built by the sabellariid worm Sabellaria nanella in the lower intertidal at Monte Hermoso beach, Argentina (39ºS). All previous records of S. nanella in the study area correspond to solitary individuals from shallow subtidal depths in coastal environments, while the present findings refer to well established reefs on stony rocks. Worms sort medium size sand grains to build the reefs, which contain higher amount of organic matter than the surrounding sediments. Size structure of worms shows multiple size cohorts that include recent recruits and mature adults. Many invertebrates, i.e. various annelids, arthropods, molluscs, nemerteans and nematodes, are the frequent organisms living within the reef, some of them already recorded in the area. The presence of intertidal reefs of S. nanella indicates that the species has plasticity to adapt to environments with different physical conditions (subtidal-intertidal areas).Fil: Bremec, Claudia Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Subsede Instituto Nacional de Investigación y Desarrollo Pesquero; ArgentinaFil: Carcedo, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Argentino de Oceanografía (i); ArgentinaFil: Piccolo, Maria Cintia. Universidad Nacional del Sur; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Argentino de Oceanografía (i); ArgentinaFil: Dos Santos, Eder Paulo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Argentino de Oceanografía (i); ArgentinaFil: Fiori, Sandra Marcela. Universidad Nacional del Sur; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Argentino de Oceanografía (i); Argentin
Interfaces entre modelo produtivo e divisão do trabalho flexível: a visão do trabalhador sobre a terceirização no polo naval de Rio Grande
O objetivo deste trabalho é trazer uma reflexão sobre a pesquisa empírica realizada no Polo Naval de Rio Grande acerca do modelo flexível de organização produtiva e seu impacto nos processos de sociabilidade da classe trabalhadora. A perspectiva que se pretende mostrar é a do trabalhador terceirizado dentro da organização da produção e da divisão do trabalho, ambos flexíveis. O presente artigo é produto de reflexões a partir do projeto de dissertação de mestrado da segunda autora sobre a invisibilidade social causada pela terceirização elaborado para o Programa de Pós-graduação em Sociologia da Universidade Federal de Pelotas
Synthesis and Characterization of Ceramide-Containing Liposomes as Membrane Models for Different T Cell Subpopulations
A fine balance of regulatory (Treg) and conventional CD4+ T cells (Tconv) is required to prevent harmful immune responses, while at the same time ensuring the development of protective immunity against pathogens. As for many cellular processes, sphingolipid metabolism also crucially modulates the Treg/Tconv balance. However, our understanding of how sphingolipid metabolism is involved in T cell biology is still evolving and a better characterization of the tools at hand is required to advance the field. Therefore, we established a reductionist liposomal membrane model system to imitate the plasma membrane of mouse Treg and Tconv with regards to their ceramide content. We found that the capacity of membranes to incorporate externally added azide-functionalized ceramide positively correlated with the ceramide content of the liposomes. Moreover, we studied the impact of the different liposomal preparations on primary mouse splenocytes in vitro. The addition of liposomes to resting, but not activated, splenocytes maintained viability with liposomes containing high amounts of C16-ceramide being most efficient. Our data thus suggest that differences in ceramide post-incorporation into Treg and Tconv reflect differences in the ceramide content of cellular membranes
MicroRNAs in cancer treatment and prognosis
Disturbances in microRNA expression by epigenetic alterations and mutations may promote not only tumorigenesis but also tumor aggressiveness, invasion, metastasis, and resistance to chemotherapy and radiotherapy. Several studies have profiled microRNA expression in normal and tumorigenic tissues, demonstrating a unique microRNA signature, which can be used as a marker for cancer diagnosis and prognosis. This review discusses the importance of microRNAs as regulatory biomolecules involved in cancer, focusing on microRNAs related to cancer invasion, metastasis, epigenetic alterations, chemoresistance, and radioresistance. The identification of both differentially expressed microRNAs in tumors and their target genes provides new tools for gene therapy; the re-expression of microRNAs silenced by cancer development or the silencing of oncogenic microRNAs can be effective in the blockade of cancer-related cell proliferation.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Italian Association for Cancer Research (AIRC)Univ Fed Sao Paulo, Dept Biochem, BR-04044020 Sao Paulo, BrazilUniv Sao Paulo, Dept Genet & Evolutionary Biol, BR-05508090 Sao Paulo, BrazilUniv Genoa, Dept Hlth Sci, I-16132 Genoa, ItalyUniv Fed Sao Paulo, Dept Biochem, BR-04044020 Sao Paulo, BrazilItalian Association for Cancer Research (AIRC): 8909Web of Scienc
Spielformen im Spielfilm : zur Medienmorphologie des Kinos nach der Postmoderne
Die aktuelle Konjunktur exzentrischen Erzählens im gegenwärtigen Kino ist längst nicht mehr bloß die Illustration einer condition postmoderne, sie verweist vielmehr auf die Hybridisierung von Erzählung und Spiel im digitalen Medienumbruch. Insbesondere im massenattraktiven Spielfilm stehen nicht mehr die selten gewordenen Identifikationsofferten im Zentrum des Interesses und die Zuschauer sorgen sich auch nicht um Interpretationshypothesen, sondern sie finden Vergnügen an Erzählrätseln und verfolgen neugierig das Spiel mit unterschiedlichen Plotvarianten oder paradoxalen Welten. In den Beiträgen dieses Bandes werden Formen dieser Hybridisierung exemplarisch aufgeschlüsselt und genealogisch nachvollzogen
Conocimientos y practicas de prevencion del dengue en la comuna 1 de Neiva y municipio de Acacias Meta y de que manera se puede evitar o erradicar esta enfermedad
TablasLa fiebre del dengue o dengue es una enfermedad vectorial causada por la picadura del insecto Aedes Aegypti, por medio de ciclos en los que se alternan un hospedero invertebrado y un vertebrado, esta puede ir desde un síndrome febril simple a choque hemorrágico causando índices de mortalidad desde edades tempranas hasta la tercera edad, a pesar de las medidas para erradicación del vector durante este pico epidemiológico se ha notado el aumento de casos probables y complicaciones.
En Colombia el dengue representa un problema prioritario en salud pública debido a múltiples factores, entre ellos la reemergencia e intensa transmisión viral con tendencia creciente, el comportamiento de ciclos epidémicos cada vez más cortos, el aumento en la frecuencia de brotes de dengue hemorrágico y otras formas graves de la enfermedad, la circulación simultánea de los cuatro serotipos, la infestación por Aedes aegypti del más del 90% del territorio nacional situado por debajo de los 2.200 m.s.n.m., y la urbanización de la población por problemas de violencia en el país, pone en riesgo a aproximadamente 25 millones de personas que habitan en zonas urbanas con transmisión de esta enfermedad.
De esta forma, el dengue es una de las patologías infecciosas con mayor impacto en Colombia y constituye un evento cuya vigilancia, prevención y control revisten especial interés en salud pública.Dengue fever or dengue vector is a disease caused by the bite of Aedes aegypti through cycles in which an alternate invertebrate and a vertebrate host, this can range from a simple febrile syndrome to hemorrhagic shock causing mortality from early childhood to old age, despite the measures for eradication of the vector during the epidemic peak has noticed an increase in probable cases and complications.
In Colombia, dengue is a priority public health problem due to multiple factors, including the re-emergence and intense viral transmission increasing tendency, the behavior of epidemic cycles getting shorter, the increased frequency of outbreaks of dengue hemorrhagic fever and other severe forms of the disease, the simultaneous circulation of the four serotypes, the Aedes aegypti infestation of more than 90% of the country fell below the 2,200 m, and the urbanization of the population problems of violence in the country, places at risk to about 25 million people living in urban areas with transmission of this disease.
Thus, dengue is one of the infectious diseases with the greatest impact in Colombia and is an event whose surveillance, prevention and control of particular public health interest
Association between the MHC gene region and variation of serum IgE levels against specific mould allergens in the horse
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