225 research outputs found
The expression signature of in vitro senescence resembles mouse but not human aging
BACKGROUND: The biological mechanisms that underlie aging have not yet been fully identified. Senescence, a phenomenon occurring in vitro, limits the number of cell divisions in mammalian cell cultures and has been suggested to contribute to aging. RESULTS: We investigated whether the changes in gene expression that occur during mammalian aging and induction of cellular senescence are similar. We compared changes of gene expression in seven microarray datasets from aging human, mouse and rat, as well as four microarray datasets from senescent cells of man and mouse. The datasets were publicly available or obtained from other laboratories. Correlation measures were used to establish similarities of the expression profiles and gene ontology analyses to identify functional groups of genes that are co-regulated. Robust similarities were established between aging in different species and tissues, indicating that there is an aging transcriptome. Although some cross-species comparisons displayed high correlation, intra-species similarities were more reliable. Similarly, a senescence transcriptome was demonstrated that is conserved across cell types. A similarity between the expression signatures of cellular senescence and aging could be established in mouse, but not in human. CONCLUSION: Our study is the first to use microarray data from several studies and laboratories for dissection of a complex biological phenotype. We demonstrate the presence of a mammalian aging transcriptome, and discuss why similarity between cellular senescence and aging is apparent in aging mice only
On Asymptotic Global Error Estimation and Control of Finite Difference Solutions for Semilinear Parabolic Equations
The aim of this paper is to extend the global error estimation and control
addressed in Lang and Verwer [SIAM J. Sci. Comput. 29, 2007] for initial value
problems to finite difference solutions of semilinear parabolic partial
differential equations. The approach presented there is combined with an
estimation of the PDE spatial truncation error by Richardson extrapolation to
estimate the overall error in the computed solution. Approximations of the
error transport equations for spatial and temporal global errors are derived by
using asymptotic estimates that neglect higher order error terms for
sufficiently small step sizes in space and time. Asymptotic control in a
discrete -norm is achieved through tolerance proportionality and uniform
or adaptive mesh refinement. Numerical examples are used to illustrate the
reliability of the estimation and control strategies
Cord blood insulinoma-associated protein 2 autoantibodies are associated with increased risk of type 1 diabetes in the population-based Diabetes Prediction in Skane study
Aims/hypothesis The aim of this study was to examine the effect of cord blood autoantibodies on the risk for type 1 diabetes in children followed prospectively from birth. Methods The Diabetes Prediction in Skane (DiPiS) study consists of 35,853 children from the general population born during 2000-2004. Samples were collected at birth and analysed for HLA genotypes and autoantibodies to glutamate decarboxylase 65 (GAD65), insulin and insulinoma-associated protein 2 (IA-2). After adjusting for HLA, sex, maternal age and parental type 1 diabetes, independent associations with risk of diabetes were assessed using multivariate Cox proportional hazards models. Results In total, 151 children (0.4%) had developed type 1 diabetes by the end of 2013 at a median age of 5.8 years (0.8-12.2 years). In the multivariate analysis, the presence of IA-2 autoantibodies (IA-2A) in cord blood (HR 6.88, 95% CI 1.46,32.4; p = 0.003), but not maternal diabetes (HR 1.38, 95% CI 0.24,7.84; p = 0.71), was associated with risk of developing type 1 diabetes. No increased risk could be seen for the presence of autoantibodies to GAD65 or insulin. Conclusions/interpretation Our study indicates that the presence of cord blood IA-2A superimposes maternal diabetes and other cord blood islet autoantibodies as a predictor of type 1 diabetes development in the child. These findings may be of significance for future screening and study protocols on type 1 diabetes prediction
Metal Recovery from Nickel Metal Hydride Batteries Using Cyanex 923 in Tricaprylylmethylammonium Nitrate from Chloride Aqueous Media
Abstract A flow sheet has been developed for recovery of metals from nickel metal hydride batteries using the neutral extractant Cyanex 923 dissolved in the ionic liquid tricaprylylmethylammonium nitrate, [A336][NO 3 ], and a synthetic chloride-based aqueous leach solution. The process allows purification of nickel in a single step by extracting chloride and nitrate complexes of the extractable transition metals and rare earths. Three selective strip operations utilizing first nitrate, stripping cobalt and manganese, and then chloride complexation, stripping the rare earths, followed by stripping of iron and zinc. Cobalt in the nitrate strip solution was separated from manganese by extraction with the ionic liquid tricaprylylmethylammonium thiocyanate, [A336] [SCN]
Utveckling av energiövervakningssystem med Production Discovery som grund
The goal of this thesis project was to develop an energy surveillance system for the Swedish production industry. The main problem this project sought to solve is that several Swedish industries are currently only able to measure the energy consumption of their entire facilities, as one big black box. They cannot determine the energy consumption of the individual machines within each and every production site. This makes it difficult to discover if any machine consumes more energy than it should. The goal of this project has therefore been to develop a system that allows the user to determine the energy consumption of all the individual parts of a production site. The project has been conducted at the company itAutomation in Malmö and is based on their product Production Discovery. The original goal was to develop a general concept for energy surveillance, which could be adapted to each customer's individual needs. However this changed halfway through the project as itAutomation received an order from AAK, a company with a production facility in Karlshamn, and the course of this thesis project changed thereafter. The aim of the project was changed from developing a general concept, to developing an energy surveillance system specifically designed for AAKâs facility. A significant amount of information for the development of a general energy surveillance concept was found during the work, such as which type of PLC would be suitable for this sort of system, which KPI-values (Key Performance Indicators) most production companies will be interested in as well as which meters and communication protocols are common within the Swedish production industry. The product for AAK was however not possible to complete, due to a faulty connection between the database Proficy Historian and the diagram tool Qlik Sense. This was such a major problem that the system as a whole did not work without them, as the two components were essential to the entire concept
Neolithic Diversities : Perspectives from a conference in Lund, Sweden
Papers from a conference in Lund, Sweden. The title of the conference was "What's new in the Neolithic". The book brings together the latest research on the Neolithic of northern Europe. In the study of the distant human past, certain events and periods have come to represent decisive passages from one human state to another. From a global perspective, the characteristic feature of the last ten thousand years is that people in different parts of the world, and at different points in time, started to grow plants and domesticate animals. The rise and dissemination of agriculture were crucial factors for the continued existence of humankind on earth. The incipient agriculture is often regarded as the very beginning of human culture, as it has traditionally been perceived in western historiography, that is, as control over nature and the âcultivationâ of intellectual abilities. As a result of the increasing national and international interest in the northern European Neolithic (4000â2000 BC), combined with large-scale archaeological excavations which helped to nuance and modify the picture of the period, senior researchers and research students formed a Neolithic group in 2010. The Department of Archaeology and Ancient History at Lund University served as the base, but the group also included collaborators from Linnaeus University and Södertörn University, and from the Southern Contract Archaeology Division of the National Heritage Board in Lund and Sydsvensk Arkeologi in Malmö and Kristianstad. Meetings and excursions in the following two years resulted in the holding of an international conference in Lund in May 2013 entitled âWhatâs New in the Neolithicâ. Invitations to this conference were sent to two dozen prominent Neolithic scholars from northern and central Europe. This publication gives aspects of innovative research on the European Neolithic
Temperature stability of intersubband transitions in AlN/GaN quantum wells
Temperature dependence of intersubband transitions in AlN/GaN multiple
quantum wells grown with molecular beam epitaxy is investigated both by
absorption studies at different temperatures and modeling of conduction-band
electrons. For the absorption study, the sample is heated in increments up to
C. The self-consistent Schr\"odinger-Poisson modeling includes
temperature effects of the band-gap and the influence of thermal expansion on
the piezoelectric field. We find that the intersubband absorption energy
decreases only by meV at C relative to its room temperature
value
Can Computers Automate Welfare?
Information-driven automated systems that deliver services proactively to citizens in need are heralded as the next level of digital government. There is, however, concern that such systems make welfare services less accessible to some citizens. This study uses the case of Norwayâs child benefit system to discuss the general obstacles to having welfare policies implemented by proactive digital systems. Norwayâs automated child benefit system uses data from Norwayâs national resident register to award this benefit to eligible parents whom the system identifies. As such, it is representative of many government systems that use registry data to perform tasks previously done by caseworkers. While the eligibility rules for child benefits are simple, and the register has sufficient data to automate most cases, many parents are not awarded the benefit automatically. This article argues that when developing automated digital services, public administrators are faced with a trilemma. Ideally, proactive automation should be (1) precise in its delivery, (2) inclusive of all citizens, and (3) still support welfare-oriented policies that are independent of the requirements of the digital system. However, limitations with each requirement prevent all three from being realized at the same time. Only two can be simultaneously realized: a public administrator must decide which of them to forego. Consequently, automated services cannot meet all the expectations of policymakers regarding the benefits of digital government. Instead, governments need to find ways of utilizing the benefits of public digitalisation without infringing on citizensâ right to be treated equally and fairly by the government
Complaint management by e-commerce companies within Facebook : a framework for complaint management
Svensk e-handel har de senaste Ären vuxit kraftigt, vilket har lett till att andelen e-handels-företag har ökat i Sverige de senaste Ären. Konsumenten har idag större valmöjlighet vid val av företag. Företagen erbjuder bra fraktvillkor, tryggare betalningsformer och mer anvÀndarvÀnliga hemsidor. Detta har gjort att förvÀntningarna hos kunden har stigit. NÄr inte företaget upp till kundens förvÀntningar och krav kan det resultera i negativa kommentarer. Relationen mellan företag och kund riskerar att bli försÀmrad. Historiskt sett skedde dessa klagomÄl via direktkontakt med företagen, men det har blivit allt vanligare att kunden uttrycker sitt klagomÄl pÄ sociala medier. Flera företag erbjuder idag kundtjÀnst via sociala medier, till exempel Twitter och Facebook. NÀr en kommentar skrivs pÄ sociala medier finns möjligheten att den nÄr en större grupp som tar emot budskapet, detta benÀms E-WoM.
Syftet med uppsatsen Àr att undersöka hur framgÄngsrika svenska e-handelsföretag med en aktiv kundtjÀnst inom sociala medier hanterar missnöjda kunder, för att förebygga eventuell negativ E-WoM. För att syftet ska uppfyllas Àmnar uppsatsen ge svar pÄ följande forskningsfrÄgor: hur hanterar fallföretagen klagomÄl pÄ sin Facebooksida och hur arbetar fallföretagen med att förebygga att klagomÄl influerar övriga konsumenter via negativ E-WoM. Syftet och frÄgestÀllningarna ska ligga till grund för ett ramverk som kan anvÀndas vid hantering av missnöjda kunder inom Facebook.
För att uppnÄ syftet och besvara frÄgorna har fallstudier och en litteraturstudie utförts.
I uppsatsens fallstudier analyseras de valda företagen Lekmer, Sportamore, Babyshop och ZooZoo. Vid val av företag fanns kriterierna att företagen enbart ska vara verksamma e-handelsföretag, att de mÄste ha tydliga konkurrenter, att företaget Àr framgÄngsrikt och att de arbetar aktivt med klagomÄlshantering. I en fallstudie undersöks företagens Facebookflöden, kundnöjdhetsindex, eventuella utmÀrkelser och Ärsredovisningar, vilket kompletterats med en mailintervju. Med kombinationen av empiri frÄn företagen och teori frÄn litteratur skapades ett gott underlag för analys.
Uppsatsens slutsats Ă€r att den ökade konkurrensen inom svensk e-handel resulterat i att företagen erbjuder bĂ€ttre erbjudanden Ă€n vad de kan hĂ„lla. NĂ€r företagen inte kan hĂ„lla vad de lovar nĂ„r de inte upp till kundens förvĂ€ntningar vilket gör att det uppstĂ„r ett missnöje hos kunden. För att hantera detta missnöje Ă€r en aktiv klagomĂ„lshantering viktig.Over the last couple of years, Swedish e-commerce has increased substantially, and as an effect, the amount of businesses within e-commerce has enhanced in Sweden as well. As of today, the customer has a great variety of companies to choose from. The companies provide good shipping terms, safer payment options and more user-friendly websites. A result of those factors is that the customer now holds higher expectations towards the companies. If the company canât reach those expectations of the customer, it may result in negative comments and reviews, which ultimately leads to a weaker relationship between the company and their customer. Historically, the customer complaints reached the company directly, while today it is more common to express complaints through different forms of social media. Today a lot of companies offer customer service through their social media-sites, for instance on Facebook and on Twitter. A comment written on any of the sites enables the possibility for the answer to reach a greater crowd, a phenomenon which goes by the name E-WoM.
The purpose of the essay is to study and analyze how successful Swedish companies within e-commerce, with an active customer service through social media, handles dissatisfied customers to prevent any possible negative E-WoM. To fulfill the aim, the essay intend to answer the following two questions: how do the companies in the chosen cases handle complaints on their Facebookpage and how do the companies in the chosen cases work to prevent complaints from reaching and influencing other customers through negative E-WoM. The purpose and the formulation of the questions will constitute the basis of a framework which can be used while handling dissatisfied customers through Facebook.
To achieve the purpose and to answer the questions, case-studies and studies through literature have been made. In the case studies of the essay, following companies have been analyzed Lekmer, Sportamore, Babyshop and ZooZoo. The companies chosen had to meet certain criteria: it had to be operational in the e-commerce business only, it had to have obvious competitors on the market, it had to be successful and finally it had to be working actively with handling of complaints. In one of the case studies, the Facebook-news feed is analyzed, along with an index of the customer satisfaction, potential awards assigned to the company and the annual reports. The case study is then completed with an interview through email. The combination of empirics from the companies and theory from the literature made up a sustainable foundation for analysis.
The conclusion of the essay is that the increase in competition within the Swedish e-commerce has caused the companies to have better offers than they actually can fulfill. When the companies cannot withhold their promises, they no longer meet the expectations of the costumers, which create dissatisfaction among the customer. To handle the dissatisfaction it is important for the company to have an active complaint management
The acidic domain of the endothelial membrane protein GPIHBP1 stabilizes lipoprotein lipase activity by preventing unfolding of its catalytic domain.
GPIHBP1 is a glycolipid-anchored membrane protein of capillary endothelial cells that binds lipoprotein lipase (LPL) within the interstitial space and shuttles it to the capillary lumen. The LPLâąGPIHBP1 complex is responsible for margination of triglyceride-rich lipoproteins along capillaries and their lipolytic processing. The current work conceptualizes a model for the GPIHBP1âąLPL interaction based on biophysical measurements with hydrogen-deuterium exchange/mass spectrometry, surface plasmon resonance, and zero-length cross-linking. According to this model, GPIHBP1 comprises two functionally distinct domains: (1) an intrinsically disordered acidic N-terminal domain; and (2) a folded C-terminal domain that tethers GPIHBP1 to the cell membrane by glycosylphosphatidylinositol. We demonstrate that these domains serve different roles in regulating the kinetics of LPL binding. Importantly, the acidic domain stabilizes LPL catalytic activity by mitigating the global unfolding of LPL's catalytic domain. This study provides a conceptual framework for understanding intravascular lipolysis and GPIHBP1 and LPL mutations causing familial chylomicronemia
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