1,955 research outputs found

    Some homogenization and corrector results for nonlinear monotone operators

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    This paper deals with the limit behaviour of the solutions of quasi-linear equations of the form \ \ds -\limfunc{div}\left(a\left(x, x/{\varepsilon _h},Du_h\right)\right)=f_h on Ω\Omega with Dirichlet boundary conditions. The sequence (εh)(\varepsilon _h) tends to 00 and the map a(x,y,ξ)a(x,y,\xi ) is periodic in yy, monotone in ξ\xi and satisfies suitable continuity conditions. It is proved that uhuu_h\rightarrow u weakly in H01,2(Ω)H_0^{1,2}(\Omega ), where uu is the solution of a homogenized problem \ -\limfunc{div}(b(x,Du))=f on Ω\Omega . We also prove some corrector results, i.e. we find (Ph)(P_h) such that DuhPh(Du)0Du_h-P_h(Du)\rightarrow 0 in L2(Ω,Rn)L^2(\Omega ,R^n)

    Correctors for some nonlinear monotone operators

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    In this paper we study homogenization of quasi-linear partial differential equations of the form -\mbox{div}\left( a\left( x,x/\varepsilon _h,Du_h\right) \right) =f_h on Ω\Omega with Dirichlet boundary conditions. Here the sequence (εh)\left( \varepsilon _h\right) tends to 00 as hh\rightarrow \infty and the map a(x,y,ξ)a\left( x,y,\xi \right) is periodic in y,y, monotone in ξ\xi and satisfies suitable continuity conditions. We prove that uhuu_h\rightarrow u weakly in W01,p(Ω)W_0^{1,p}\left( \Omega \right) as h,h\rightarrow \infty , where uu is the solution of a homogenized problem of the form -\mbox{div}\left( b\left( x,Du\right) \right) =f on Ω.\Omega . We also derive an explicit expression for the homogenized operator bb and prove some corrector results, i.e. we find (Ph)\left( P_h\right) such that DuhPh(Du)0Du_h-P_h\left( Du\right) \rightarrow 0 in Lp(Ω,Rn)L^p\left( \Omega, \mathbf{R}^n\right)

    Global well-posedness of the short-pulse and sine-Gordon equations in energy space

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    We prove global well-posedness of the short-pulse equation with small initial data in Sobolev space H2H^2. Our analysis relies on local well-posedness results of Sch\"afer & Wayne, the correspondence of the short-pulse equation to the sine-Gordon equation in characteristic coordinates, and a number of conserved quantities of the short-pulse equation. We also prove local and global well-posedness of the sine-Gordon equation in an appropriate function space.Comment: 17 pages, revised versio

    AHNAK and inflammatory markers predict poor survival in laryngeal carcinoma.

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    AHNAK/Desmoyokin is a giant protein which has been recently linked to reorganization of the actin cytoskeleton, cellular migration and invasion. Here, we investigated the role of AHNAK in the pathophysiology of larynx carcinoma-one of the major subtypes of head and neck cancer. To this end, we analysed AHNAK expression in tumor tissues from 83 larynx carcinoma patients in relation to overall survival. We found that tumoral AHNAK overexpression significantly associated with poor survival of these patients both in univariate and multivariate analysis. In further studies, we combined the prognostic value of AHNAK with selected markers of inflammation, such as macrophage migration inhibitory factor (MIF) and tumor-infiltrating neutrophils (CD66b-positive cells). Both MIF and neutrophils have been linked to enhanced tumoral migration and poor clinical outcome in patients with orohypopharynx carcinoma-another major subtype of head and neck cancer. Interestingly, we found that synchronous high levels of AHNAK and MIF or AHNAK and neutrophils, respectively, were stronger predictors of poor survival than AHNAK alone. Synchronous high levels of all three markers were the strongest predictors of poor survival in our patient cohort. Taken together, our findings propose novel strategies for an accurate prognosis in larynx carcinoma and suggest potential mechanisms of inflammation-mediated tumor progression

    Анализ эффективности осаждения влаги в выносных сепараторах АЭС

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    Объектом исследования является внешняя сепарация пара на АЭС Цель работы – провести анализ эффективности осаждения влаги во внешних сепараторах АЭС. Определить влияние конструктивных факторов на процесс осаждения влаги и течения пара. На основе полученных результатов сравнить различные конструкции сепараторов, описать их преимущества и недостатки. В процессе исследования проводились математическое и компьютерное моделирования течения влажного пара с помощью ПК FlowVision и программирования в среде Visual Basic. В результате исследования были получены зависимости эффективности осаждения влаги и значения гидравлического сопротивления от характерных геометрических размеров жалюзийных сепараторов. Экономическая эффективность/значимость работы заключается в исследовании возможностей повышеThe object of this study is the external separation at the nuclear power plant. The purpose of the study is to analyze the efficiency of precipitation of moisture in the external separator; to determine the relation of structural factors to the process of catching of moisture and vapor flow; use these data to compare different designs of separators, describe their advantages and disadvantages. The study carried out using mathematical and computer modeling of wet steam flow with a SP FlowVision and programming in Visual Basic environment. The results of the study are relations of the efficiency of precipitation and hydraulic resistance to the characteristic geometric factors of corrugated plates separators. Cost-effectiveness / value of the work concludes in the possibilities of improv

    Архитектура системы ситуационного управления

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    This article related to situation management. It contains architecture of situation management system and class diagram of situation management agent

    Петрология, геохимия и рудоносность анорогенных гранитоидов шибеликского комплекса Горного Алтая

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    Актуальность проведенных исследований определяется необходимостью изучения петрологии, геохимии и оруденения анорогенных гранитоидов шибеликского комплекса Горного Алтая, который представлен сильно фракционированными разностями. С ними пространственно и парагенетически связаны различные типы оруденения Zr, Nb, Ta и TR. Цель исследования: изучить петрологические, геохимические особенности пород, акцессорного циркона и оруденения Шибеликского ареала с использованием экспериментальных диаграмм, позволяющих выявлять генетические проблемы и физико-химические особенности магматогенного и гидротермального цирконов. Методы исследований включали изучение зональных и незональных кристаллов сфена и апатита с применением лазерно-абляционного анализа методом индуктивно-связанной плазмы на спектрометре «ОРTIMA-4300» с высокой чувствительностью определения элементов в Лаборатории Объединённого института геологии и геофизики Сибирского отделения РАН (г. Новосибирск). Определение элементов-примесей в цирконах выполнено методом LA-ICP-MS (масс-спектрометрия с индуктивно связанной плазмой и с лазерной абляцией) на масс-спектрометре ELEMENT 2 (фирма Thermo Finnigan Mat) с лазерной приставкой UP-2B, Nd: YAG (фирма New Wave Research) в ИГМ СО РАН (г. Новосибирск). Результаты. В статье приведены данные по геохимии и петрологии щелочных гранитоидов, магматического и гидротермального циркона шибеликского комплекса Горного Алтая. На основе представительных анализов пород и акцессорного циркона расшифровываются особенности генерации гранитоидов, их рудоносности и типизации. Гранитоиды отнесены к агпаитовым сильно фракционированным разностям. В них и в цирконе проявлен тетрадный эффект фракционирования (ТЭФ) РЗЭ М-типа, обусловленный высокой насыщенностью фтор-обогащёнными флюидами. Увеличение значений ТЭФ РЗЭ коррелируется с возрастанием кислотности среды. Выявляется экстремальная некогерентность отношений элементов к хондриту и несоответствие поведения заряд-радиусным характеристикам. Магматогенный циркон характеризуется призматической и пирамидальной формой кристаллов и высокими концентрациями Hf, Y, Sc и тяжёлых РЗЭ. Гидротермальный циркон имеет более высокие концентрации Nb, Ta и суммы TR.The relevance of the discussed issue is caused by the need of researching petrology, geochemistry and ore mineralization of anorogenic granitoids of Shibelikskii complex which is represented by strong fractionated rocks. Different types of ore mineralization of Zr, Nb, Ta and REE are related to such rocks spatially and paragenetically. The main aim of the research is to study petrology, geochemical features of rocks, accessory mineral zircon and ore mineralization of Shibelikskii areal using the experimental diagrams, which allow revealing the genetic problems and determining physic-chemical features of magamatic and hydrothermal zircon crystals. The methods used in the study. Rare and scattered elements were determined in rocks by inductively coupled plasma method on the mass spectrometer «ОРTIMA-4300», the rest elements, including REE, were determined by La-ISP-MS methods in the Laboratory OIGaG SO RAN (Novosibirsk). Chemical elements in zircon were determined by La-ISP-MS mass-spectrometry method with inductively coupled plasma and laser ablation on the mass-spectrometer ELEMENT 2 (Thermo Finnigan Mat) with laser device UP-2B, Nd: YAG (New Wave Research) in the Laboratory OIGaG SO RAN (Novosibirsk). Results. The paper introduces the data on geochemistry and petrology of alkali granitoids and accessory magmatic and hydrothermal zircon of Shibelikskii complex in Gorny Altai. Based on the representative analysis of rocks and zircon the features of granitoids generation, their ore mineralization and typification are determined. The granitoids refer to agpaitic strong fractionation rocks. The tetradic effect of REE M-type fractionation appears in the rocks and in zircon. It is caused by high saturation with fluoro-rich fluids. Increase in meanings of tetradic effect of REE is correlated with the growth of the environment acidity. The author has determined the extreme non-coherence of elements ratio to chondrite and non-conformity of behavior to charge-and-radius-controlled characteristics. Magmatic zircon is characterized by prismatic and pyramid crystal form and high contents of Hf, Y, Sc, and heavy REE. Hydrothermal zircon has higher contents of Nb, Ta and sum of REE

    Advances in genome-wide RNAi cellular screens: a case study using the Drosophila JAK/STAT pathway

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    BACKGROUND: Genome-scale RNA-interference (RNAi) screens are becoming ever more common gene discovery tools. However, whilst every screen identifies interacting genes, less attention has been given to how factors such as library design and post-screening bioinformatics may be effecting the data generated. RESULTS: Here we present a new genome-wide RNAi screen of the Drosophila JAK/STAT signalling pathway undertaken in the Sheffield RNAi Screening Facility (SRSF). This screen was carried out using a second-generation, computationally optimised dsRNA library and analysed using current methods and bioinformatic tools. To examine advances in RNAi screening technology, we compare this screen to a biologically very similar screen undertaken in 2005 with a first-generation library. Both screens used the same cell line, reporters and experimental design, with the SRSF screen identifying 42 putative regulators of JAK/STAT signalling, 22 of which verified in a secondary screen and 16 verified with an independent probe design. Following reanalysis of the original screen data, comparisons of the two gene lists allows us to make estimates of false discovery rates in the SRSF data and to conduct an assessment of off-target effects (OTEs) associated with both libraries. We discuss the differences and similarities between the resulting data sets and examine the relative improvements in gene discovery protocols. CONCLUSIONS: Our work represents one of the first direct comparisons between first- and second-generation libraries and shows that modern library designs together with methodological advances have had a significant influence on genome-scale RNAi screens

    Nuevas perspectivas sobre el volcanismo holocénico ecuatoriano y sus repetidos impactos en el valle de Jama

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    La investigación arqueológica de campo sostenida en el valle de Jama de la costa manabita, en las décadas de 1980 y 1990, documentó la presencia de tres capas de tefra que representan erupciones volcánicas a gran escala (IEV = 4-5) emitidas desde la cuenca de Quito y áreas circundantes, todas las cuales tuvieron impactos cataclísmicos en varias culturas prehispánicas que resultaron en el abandono o la despoblación del valle durante varias décadas en dos casos y varios siglos en un caso. Estas fueron ocupaciones de las culturas Valdivia Terminal (fase 8a), Chorrera y Jama-Coaque I (fase Muchique 1), que se extendieron desde ca. 2030 a. C. a 90 d. C. y que fueron afectadas por erupciones de los volcanes Guagua Pichincha, Pululahua y otra vez del primero, respectivamente. Una investigación tefrocronológica más reciente en la Costa ecuatoriana, realizada por Vallejo Vargas (2011), ha documentado la presencia de al menos cinco eventos volcánicos adicionales del Holoceno en este paisaje distal (IEV = 4-6), pero sin asociaciones arqueológicas en este caso. Este artículo presenta nueva información arqueológica sobre esta compleja secuencia de tefras de ocho erupciones con una duración total de 5700 años (5940 a 240 AP), emitidas por cinco volcanes diferentes de la Sierra ecuatoriana. Estas rupturas/empujes repetidos debido a desastres naturales y sus variados impactos en la secuencia cultural contribuyen al entendimiento de las distintas ocupaciones prehispánicas y a las inferencias referentes al tempo y ritmo de cambio cultural y sociopolítico en cada fase arqueológica a través del tiempo

    Persistent clinical efficacy and safety of anti-tumour necrosis factor \textgreeka therapy with infliximab in patients with ankylosing spondylitis over 5 years: evidence for different types of response

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    Background: There is insufficient evidence for the long-term efficacy and safety of anti-tumour necrosis factor therapy in patients with ankylosing spondylitis (AS). This is the first report on the treatment with infliximab over 5 years.Methods: As part of a multicentre randomised trial, 69 patients with active AS at baseline (BL) have been continuously treated with infliximab (5 mg/kg i.v. every 6 weeks)---except for a short discontinuation after 3 years (FU1). The primary outcome of this extension was remission according to the ASsessment in Ankylosing Spondylitis (ASAS) criteria at the end of year 5 of the study (FU2).Results: Of the 43 patients who completed year 3, 42 agreed to continue, 38 of which (90.5%) finished year 5 (55% of 69 initially). Partial clinical remission was achieved in 13 of 38 patients (34.2%) at FU1 and FU2. At FU2, the mean Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) was 2.5±1.9 (BL:6.4, FU1:2.5). BASDAI values <4 were seen in 79% of patients at both, FU1 and FU2. ASAS 20% and 40% responses were seen in 32 (84%) and 24 (63%) patients at FU2, respectively. Most patients classified as non-responders at FU2 were part-time responders, as all but one patient achieved an ASAS 20% response at least once within the last 2 years. Three types of responders were identified. No major side effects occurred during years 4 and 5 of infliximab therapy.Conclusions: Infliximab is safe and efficacious in AS patients over 5 years. The majority of the patients remained on treatment and had rather persistent levels of low disease activity. Different response types could be identified
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