21 research outputs found

    Extrapolation von in-situ LandoberflÀchentemperaturen auf Satellitenpixel

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    Zur Validierung von Satelliten-LandoberflĂ€chentemperaturen werden kontinuierliche in-situ Messungen benötigt, die reprĂ€sentativ fĂŒr die LandoberflĂ€che in dem zu validierenden Satellitenpixel sind. Diese Arbeit stellt eine Methode zur Extrapolation der in-situ LandoberflĂ€chentemperaturen auf Satellitenpixel vor und vergleicht diese mit modellierten LandoberflĂ€chentemperaturen der gleichen FlĂ€che

    Long Term Validation of Land Surface Temperature Retrieved from MSG/SEVIRI with Continuous in-Situ Measurements in Africa

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    Since 2005, the Land Surface Analysis Satellite Application Facility (LSA SAF) operationally retrieves Land Surface Temperature (LST) for the Spinning Enhanced Visible and Infrared Imager (SEVIRI) on board Meteosat Second Generation (MSG). The high temporal resolution of the Meteosat satellites and their long term availability since 1977 make their data highly valuable for climate studies. In order to ensure that the LSA SAF LST product continuously meets its target accuracy of 2 °C, it is validated with in-situ measurements from four dedicated LST validation stations. Three stations are located in highly homogenous areas in Africa (semiarid bush, desert, and Kalahari semi-desert) and typically provide thousands of monthly match-ups with LSA SAF LST, which are used to perform seasonally resolved validations. An uncertainty analysis performed for desert station Gobabeb yielded an estimate of total in-situ LST uncertainty of 0.8 ± 0.12 °C. Ignoring rainy seasons, the results for the period 2009–2014 show that LSA SAF LST consistently meets its target accuracy: the highest mean root-mean-square error (RMSE) for LSA SAF LST over the African stations was 1.6 °C while mean absolute bias was 0.1 °C. Nighttime and daytime biases were up to 0.7 °C but had opposite signs: when evaluated together, these partially compensated each other

    The STRING database in 2021: customizable protein-protein networks, and functional characterization of user-uploaded gene/measurement sets.

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    Cellular life depends on a complex web of functional associations between biomolecules. Among these associations, protein-protein interactions are particularly important due to their versatility, specificity and adaptability. The STRING database aims to integrate all known and predicted associations between proteins, including both physical interactions as well as functional associations. To achieve this, STRING collects and scores evidence from a number of sources: (i) automated text mining of the scientific literature, (ii) databases of interaction experiments and annotated complexes/pathways, (iii) computational interaction predictions from co-expression and from conserved genomic context and (iv) systematic transfers of interaction evidence from one organism to another. STRING aims for wide coverage; the upcoming version 11.5 of the resource will contain more than 14 000 organisms. In this update paper, we describe changes to the text-mining system, a new scoring-mode for physical interactions, as well as extensive user interface features for customizing, extending and sharing protein networks. In addition, we describe how to query STRING with genome-wide, experimental data, including the automated detection of enriched functionalities and potential biases in the user's query data. The STRING resource is available online, at https://string-db.org/

    The STRING database in 2023: protein-protein association networks and functional enrichment analyses for any sequenced genome of interest

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    Much of the complexity within cells arises from functional and regulatory interactions among proteins. The core of these interactions is increasingly known, but novel interactions continue to be discovered, and the information remains scattered across different database resources, experimental modalities and levels of mechanistic detail. The STRING database (https://string-db.org/) systematically collects and integrates protein-protein interactions-both physical interactions as well as functional associations. The data originate from a number of sources: automated text mining of the scientific literature, computational interaction predictions from co-expression, conserved genomic context, databases of interaction experiments and known complexes/pathways from curated sources. All of these interactions are critically assessed, scored, and subsequently automatically transferred to less well-studied organisms using hierarchical orthology information. The data can be accessed via the website, but also programmatically and via bulk downloads. The most recent developments in STRING (version 12.0) are: (i) it is now possible to create, browse and analyze a full interaction network for any novel genome of interest, by submitting its complement of encoded proteins, (ii) the co-expression channel now uses variational auto-encoders to predict interactions, and it covers two new sources, single-cell RNA-seq and experimental proteomics data and (iii) the confidence in each experimentally derived interaction is now estimated based on the detection method used, and communicated to the user in the web-interface. Furthermore, STRING continues to enhance its facilities for functional enrichment analysis, which are now fully available also for user-submitted genomes

    Magnetoresistance through a single molecule

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    The use of single molecules to design electronic devices is an extremely challenging and fundamentally different approach to further downsizing electronic circuits. Two-terminal molecular devices such as diodes were first predicted [1] and, more recently, measured experimentally [2]. The addition of a gate then enabled the study of molecular transistors [3-5]. In general terms, in order to increase data processing capabilities, one may not only consider the electron's charge but also its spin [6,7]. This concept has been pioneered in giant magnetoresistance (GMR) junctions that consist of thin metallic films [8,9]. Spin transport across molecules, i.e. Molecular Spintronics remains, however, a challenging endeavor. As an important first step in this field, we have performed an experimental and theoretical study on spin transport across a molecular GMR junction consisting of two ferromagnetic electrodes bridged by a single hydrogen phthalocyanine (H2Pc) molecule. We observe that even though H2Pc in itself is nonmagnetic, incorporating it into a molecular junction can enhance the magnetoresistance by one order of magnitude to 52%.Comment: To appear in Nature Nanotechnology. Present version is the first submission to Nature Nanotechnology, from May 18th, 201

    Web Queries as a Source for Syndromic Surveillance

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    In the field of syndromic surveillance, various sources are exploited for outbreak detection, monitoring and prediction. This paper describes a study on queries submitted to a medical web site, with influenza as a case study. The hypothesis of the work was that queries on influenza and influenza-like illness would provide a basis for the estimation of the timing of the peak and the intensity of the yearly influenza outbreaks that would be as good as the existing laboratory and sentinel surveillance. We calculated the occurrence of various queries related to influenza from search logs submitted to a Swedish medical web site for two influenza seasons. These figures were subsequently used to generate two models, one to estimate the number of laboratory verified influenza cases and one to estimate the proportion of patients with influenza-like illness reported by selected General Practitioners in Sweden. We applied an approach designed for highly correlated data, partial least squares regression. In our work, we found that certain web queries on influenza follow the same pattern as that obtained by the two other surveillance systems for influenza epidemics, and that they have equal power for the estimation of the influenza burden in society. Web queries give a unique access to ill individuals who are not (yet) seeking care. This paper shows the potential of web queries as an accurate, cheap and labour extensive source for syndromic surveillance

    The STRING database in 2021: customizable protein–protein networks, and functional characterization of user-uploaded gene/measurement sets

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    Cellular life depends on a complex web of functional associations between biomolecules. Among these associations, protein–protein interactions are particularly important due to their versatility, specificity and adaptability. The STRING database aims to integrate all known and predicted associations between proteins, including both physical interactions as well as functional associations. To achieve this, STRING collects and scores evidence from a number of sources: (i) automated text mining of the scientific literature, (ii) databases of interaction experiments and annotated complexes/pathways, (iii) computational interaction predictions from co-expression and from conserved genomic context and (iv) systematic transfers of interaction evidence from one organism to another. STRING aims for wide coverage; the upcoming version 11.5 of the resource will contain more than 14 000 organisms. In this update paper, we describe changes to the text-mining system, a new scoring-mode for physical interactions, as well as extensive user interface features for customizing, extending and sharing protein networks. In addition, we describe how to query STRING with genome-wide, experimental data, including the automated detection of enriched functionalities and potential biases in the user's query data. The STRING resource is available online, at https://string-db.org/.</p

    Resection of the primary tumour versus no resection prior to systemic therapy in patients with colon cancer and synchronous unresectable metastases (UICC stage IV): SYNCHRONOUS - a randomised controlled multicentre trial (ISRCTN30964555)

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    <p>Abstract</p> <p>Background</p> <p>Currently, it remains unclear, if patients with colon cancer and synchronous unresectable metastases who present without severe symptoms should undergo resection of the primary tumour prior to systemic chemotherapy. Resection of the primary tumour may be associated with significant morbidity and delays the beginning of chemotherapy. However, it may prevent local symptoms and may, moreover, prolong survival as has been demonstrated in patients with metastatic renal cell carcinoma. It is the aim of the present randomised controlled trial to evaluate the efficacy of primary tumour resection prior to systemic chemotherapy to prolong survival in patients with newly diagnosed colon cancer who are not amenable to curative therapy.</p> <p>Methods/design</p> <p>The SYNCHRONOUS trial is a multicentre, randomised, controlled, superiority trial with a two-group parallel design. Colon cancer patients with synchronous unresectable metastases are eligible for inclusion. Exclusion criteria are primary tumour-related symptoms, inability to tolerate surgery and/or systemic chemotherapy and history of another primary cancer. Resection of the primary tumour as well as systemic chemotherapy is provided according to the standards of the participating institution. The primary endpoint is overall survival that is assessed with a minimum follow-up of 36 months. Furthermore, it is the objective of the trial to assess the safety of both treatment strategies as well as quality of life.</p> <p>Discussion</p> <p>The SYNCHRONOUS trial is a multicentre, randomised, controlled trial to assess the efficacy and safety of primary tumour resection before beginning of systemic chemotherapy in patients with metastatic colon cancer not amenable to curative therapy.</p> <p>Trial registration</p> <p><a href="http://www.controlled-trials.com/ISRCTN30964555">ISRCTN30964555</a></p

    Global change effects on plant communities are magnified by time and the number of global change factors imposed

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    Global change drivers (GCDs) are expected to alter community structure and consequently, the services that ecosystems provide. Yet, few experimental investigations have examined effects of GCDs on plant community structure across multiple ecosystem types, and those that do exist present conflicting patterns. In an unprecedented global synthesis of over 100 experiments that manipulated factors linked to GCDs, we show that herbaceous plant community responses depend on experimental manipulation length and number of factors manipulated. We found that plant communities are fairly resistant to experimentally manipulated GCDs in the short term (<10 y). In contrast, long-term (≄10 y) experiments show increasing community divergence of treatments from control conditions. Surprisingly, these community responses occurred with similar frequency across the GCD types manipulated in our database. However, community responses were more common when 3 or more GCDs were simultaneously manipulated, suggesting the emergence of additive or synergistic effects of multiple drivers, particularly over long time periods. In half of the cases, GCD manipulations caused a difference in community composition without a corresponding species richness difference, indicating that species reordering or replacement is an important mechanism of community responses to GCDs and should be given greater consideration when examining consequences of GCDs for the biodiversity–ecosystem function relationship. Human activities are currently driving unparalleled global changes worldwide. Our analyses provide the most comprehensive evidence to date that these human activities may have widespread impacts on plant community composition globally, which will increase in frequency over time and be greater in areas where communities face multiple GCDs simultaneously

    Jovanka kommt an! Stadtgestaltung fĂŒr einen inklusiven Campus Lichtwiese. StĂ€dtebaulicher Entwurf im Sommersemester 2017.

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    Der TU Darmstadt Campus Lichtwiese wird sich in den nĂ€chsten Jahrzehnten stark entwickeln. Zur Debatte stehen eines neues MobilitĂ€tskonzept, die Neuordnung der FreiflĂ€chen und Nachverdichtung durch studentisches Wohnen. In Rahmen des Entwurfs sollen in Zusammenarbeit mit Studierenden mit eingeschrĂ€nkter MobilitĂ€t, Seh- oder HöreinschrĂ€nkung, und Newcomern in Darmstadt Konzepte entwickelt werden, die ZugĂ€nglichkeit und AufenthaltsqualitĂ€t des Campus (fĂŒr eine der Gruppen) im Sinne des Universal Design und des Access for All erhöhen
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