153 research outputs found
Stream biofilm response to an increasing number of non-flow periods
Anthropogenic impacts and climate change are considerably altering freshwater systems. Most significant consequences of this are changes to flow regimes as well as the transformation of permanent into temporary waterways. This is problematic, as despite their role in supporting biodiversity and ecosystem processes, temporary waterways are undervalued and poorly understood. In fact, although the effects of non-flow periods are known, there is a lack of knowledge regarding how changes in frequency and duration of non-flow periods influence temporary waterways. Therefore, the goal of further research is to extend the current knowledge surrounding the effects of temporal components on the aquatic ecosystem. This bachelor thesis aims to identify how the frequency of non-flow periods affects autotrophic and heterotrophic stream biofilm. With this objective, an experiment at the Experimental Stream Facility of Catalan Institute for Water Research (ICRA) was performed. The treatments consisted of one drought duration (28 days) and three frequencies (1 period of 28, 2 periods of 14, 4 periods of 7 non-flow days). The development of the autotrophic and heterotrophic stream biofilm was measured during flow periods by means of yield of photochemistry, aerobic respiration, ecosystem metabolism and ash free dry mass. The hypotheses were that with increasing frequency, the effects on stream biofilm are less because the number of subsequent non-flow days is smaller and thus the biofilm is less stressed, and that autotrophs in the epipsammic biofilm recover more slowly than in the epilithic biofilm, because the amount of water retained in sand is higher. Both hypotheses were partially confirmed, as an increasing frequency only lessened the effect on epipsammic biofilm and only autotrophic function recovered more slowly in sand than on cobbles. In addition, the majority of the variables experienced the most severe impact and thus the quickest recovery in the same treatment. Nevertheless, at the end of the experiment none of the differences persisted. Therefore, the frequency of non-flow periods only had an effect on a short-term but not on a long-term scale and consequently, both hypotheses were discarded
âSocialist accountingâ by Karl Polanyi: with preface âsocialism and the embedded economyâ
Ariane Fischer, David Woodruff, and Johanna Bockman have translated Karl Polanyiâs âSozialistische Rechnungslegungâ [âSocialist Accountingâ] from 1922. In this article, Polanyi laid out his model of a future socialism, a world in which the economy is subordinated to society. Polanyi described the nature of this society and a kind of socialism that he would remain committed to his entire life. Accompanying the translation is the preface titled âSocialism and the embedded economy.â In the preface, Bockman explains the historical context of the article and its significance to the socialist calculation debate, the social sciences, and socialism more broadly. Based on her reading of the accounting and society that Polanyi offers here, Bockman argues that scholars have too narrowly used Polanyiâs work to support the Keynesian welfare state to the exclusion of other institutions, have too broadly used his work to study social institutions indiscriminately, and have not recognized that his work shares fundamental commonalities with and often unacknowledged distinctions from neoclassical economics
Oscillations and temporal signalling in cells
ArXiv pre-print: http://arxiv.org/abs/q-bio/0703047.-- Final full-text version of the paper available at: http://dx.doi.org/10.1088/1478-3975/4/2/R01.PMID: 17664651The development of new techniques to quantitatively measure gene expression in cells has shed light on a number of systems that display oscillations in protein concentration. Here we review the different mechanisms which can produce oscillations in gene expression or protein concentration using a framework of simple mathematical models. We focus on three eukaryotic genetic regulatory networks which show ultradian oscillations, with a time period of the order of hours, and involve, respectively, proteins important for development (Hes1), apoptosis (p53) and immune response (NF-ÎșB). We argue that underlying all three is a common design consisting of a negative feedback loop with time delay which is responsible for the oscillatory behaviour.SK, MHJ and KS acknowledge support from the Danish National Research Foundation and Villum Kann Rasmussen Foundation. GT acknowledges support from the FIRB 2003 program of the
Italian Ministry for University and Scientific Research
Single cell sequencing reveals endothelial plasticity with transient mesenchymal activation after myocardial infarction.
Endothelial cells play a critical role in the adaptation of tissues to injury. Tissue ischemia induced by infarction leads to profound changes in endothelial cell functions and can induce transition to a mesenchymal state. Here we explore the kinetics and individual cellular responses of endothelial cells after myocardial infarction by using single cell RNA sequencing. This study demonstrates a time dependent switch in endothelial cell proliferation and inflammation associated with transient changes in metabolic gene signatures. Trajectory analysis reveals that the majority of endothelial cells 3 to 7 days after myocardial infarction acquire a transient state, characterized by mesenchymal gene expression, which returns to baseline 14 days after injury. Lineage tracing, using the Cdh5-CreERT2;mT/mG mice followed by single cell RNA sequencing, confirms the transient mesenchymal transition and reveals additional hypoxic and inflammatory signatures of endothelial cells during early and late states after injury. These data suggest that endothelial cells undergo a transient mes-enchymal activation concomitant with a metabolic adaptation within the first days after myocardial infarction but do not acquire a long-term mesenchymal fate. This mesenchymal activation may facilitate endothelial cell migration and clonal expansion to regenerate the vascular network
Mit BiodiversiÀt die SDGs erreichen
Die Agenda 2030 fĂŒr nachhaltige Entwicklung mit den darin enthaltenen 17 globalen Zielen fĂŒr nachhaltige Entwicklung (Sustainable Development Goals SDGs) zeigt einen neuen Weg des Gleichgewichts fĂŒr die Menschheit und den Planeten auf. Die SDGs sind stark miteinander verknĂŒpft. Deshalb werden sie in ihrer Gesamtheit nur durch transformativen Wandel unserer Gesellschaften erreicht werden können. Neuere Studien zu den Wechselwirkungen zwischen den SDGs haben den Erhalt der BiodiversitĂ€t als einen der stĂ€rksten Hebel zur Erreichung von Nachhaltigkeit identifiziert. Die auf BiodiversitĂ€t fokussierten SDGs 14 (Leben unter Wasser) und 15 (Leben an Land) zeigen eine ausgesprochen positive Wirkung, einen Zusatznutzen, auf die Erreichung anderer Ziele. Dieses Faktenblatt erlĂ€utert die Bedeutung der BiodiversitĂ€t und zeigt Optionen fĂŒr EntscheidungstrĂ€ger auf, welche Ansatzpunkte fĂŒr transformativen Wandel genutzt werden können
Atteindre les ODD avec la biodiversité
LâAgenda 2030 pour le dĂ©veloppement durable, assorti de ses 17 objectifs de dĂ©veloppement durable (ODD), trace une nouvelle voie dâĂ©quilibre pour la planĂšte et lâhumanitĂ©. Les ODD, Ă©troitement interconnectĂ©s, ne pourront se rĂ©aliser que moyennant de profonds changements dans nos sociĂ©tĂ©s. Des Ă©tudes rĂ©centes concernant les interactions entre les ODD identifient la sauvegarde de la biodiversitĂ© comme Ă©tant lâun des leviers les plus efficaces pour rĂ©aliser la durabilitĂ©. Les ODD 14 (vie aquatique) et 15 (vie terrestre) axĂ©s sur la biodiversitĂ© apparaissent comme des multiplicateurs de co-bĂ©nĂ©fices. La prĂ©sente fiche dâinformation a pour but dâexpliquer lâimportance de la biodiversitĂ© dans la mise en Ćuvre de tous les ODD et de fournir aux dĂ©cideurs des options et des points dâaccĂšs Ă un changement en profondeur.Obrecht A, Pham-Truffert M, Spehn E et al (2021) Atteindre les ODD avec la biodiversitĂ©. Swiss Academies Factsheet 16 (1
Literacy in Lithuania. Country Report - Children and Adolescents
European Literacy policy network (ELINET
Evaluation der berufsbezogenen Deutschsprachförderung nach § 45a AufenthG: Abschlussbericht
Die berufsbezogene Deutschsprachförderung gemÀà §45a des Aufenthaltsgesetzes ist seit 2016 ein Regelinstrument, dessen Ziel der Erwerb berufsbezogener deutscher Sprachkenntnisse durch Zugewanderte ist. Die Evaluation untersucht, ob die Ziele der berufsbezogenen Deutschsprachförderung erreicht werden, wie sich die berufsbezogene Deutschsprachförderung im Speziellen auf die Arbeitsmarktintegration der Teilnehmenden auswirkt, welche Zielgruppen besonders von ihr profitieren, welche Faktoren die Wirkungen der berufsbezogenen Deutschsprachförderung fördern oder hemmen und welche Empfehlungen sich aus den Ergebnisse der Untersuchung ableiten lassen.Since 2016, German language courses for professional purposes in accordance with §45a of the German Residence Act have been a regular instrument in German integration policy. The goal of these courses is the acquisition of job-related German language skills by immigrants. The evaluation examines whether the goals of job-related German language training are achieved, how job-related German language training affect the labour market integration of participants, which target groups particularly benefit from it, which factors promote or inhibit the effects of job-related German language training and which recommendations can be derived from the results of the study
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