711 research outputs found

    Only small changes in soil organic carbon and charcoal concentrations found one year after experimental slash-and-burn in a temperate deciduous forest

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    International audienceAnthropogenic fires affected the temperate deciduous forests of Central Europe over millennia. Biomass burning releases carbon to the atmosphere and produces charcoal, which potentially contributes to the stable soil carbon pools and is an important archive of environmental history. The fate of charcoal in soils of temperate deciduous forests, i.e. the processes of charcoal incorporation and transportation, and the effects on soil organic matter are still not clear. In a long-term experimental burning site, we investigated the effects of slash-and-burn and determined soil organic carbon, charcoal carbon and nitrogen concentrations and the soil lightness of colour (L*) in the topmost soil material (0?1, 1?2.5 and 2.5?5 cm depths) before, immediately after the fire and one year after burning. The main results are that (i) only few charcoal particles from the forest floor were incorporated into the soil matrix by soil mixing animals. In 0?1 cm and during one year, the charcoal C concentrations increased only by 0.4 g kg?1 and the proportion of charcoal C to SOC concentrations increased from 2.8 to 3.4%; (ii) the SOC concentrations did not show any significant differences; (iii) soil lightness significantly decreased in the topmost soil layer and correlated with the concentrations of charcoal C (r=-0.87**) and SOC (r=?0.94**) in samples 0?5 cm. We concluded that the soil colour depends on the proportion of aromatic charcoal carbon in total organic matter and that Holocene burning could have influenced soil charcoal concentrations and soil colour

    Influence of the sample dimension and yarn type on the washing relaxation process of knitted fabrics

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    U iskrojavanju odjeće ili tehničkog tekstila, treba se voditi računa o procesu relaksacije pletenih materijala nakon prozvodnje. Vrlo velike dimenzijske promjene mogu se pojaviti tijekog duljeg vremena relaksacije u suhom stanju, relaksacije u mokrom stanju ili relaksacije tijekom pranja. Relaksacija u procesu pranja može imati vrlo velik utjecaj na pletivo. Osim toga konstrukcija pletiva i vrsta pređe te dimenzije pletiva također mogu znatno utjecati na proces relasacije. U se ovom radu prikazuju detaljna ispitivanja prvih 50 ciklusa pranja uzoraka različitih dimenzija izrađenih od različitih vrsta pređe. Uspoređuju se svojstva uzoraka od konvencionalnih pređa i elektrovodljivih pređa koje se upotrebljavaju u izradi (tehnologijama) senzora. Za analizu ponašanja tijekom relaksacije razmatrala se širina očice u različitim dijelovima ispitivanih uzoraka.While tailoring a garment or a technical textile, relaxation processes of a knitted fabric after production have to be taken into account. Such dimensional changes can occur during a long time of dry relaxation, during wet relaxation, or during washing relaxation, the latter having the strongest influence on a fabric. Besides fabric construction and yarn material, the dimensions of a knitted fabric also strongly influence the relaxation process. Our paper shows a detailed analysis of the first 50 washing cycles for different fabric dimensions and yarn parameters, comparing conventional yarns and a conductive yarn used in sensory technologies. Stitch width in different location in fabric samples were considered for analyzing the relaxation behavior

    Evidence for a palaeo-subglacial lake on the Antarctic continental shelf

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    Subglacial lakes are widespread beneath the Antarctic Ice Sheet but their control on ice-sheet dynamics and their ability to harbour life remain poorly characterized. Here we present evidence for a palaeo-subglacial lake on the Antarctic continental shelf. A distinct sediment facies recovered from a bedrock basin in Pine Island Bay indicates deposition within a low-energy lake environment. Diffusive-advection modelling demonstrates that low chloride concentrations in the pore water of the corresponding sediments can only be explained by initial deposition of this facies in a freshwater setting. These observations indicate that an active subglacial meltwater network, similar to that observed beneath the extant ice sheet, was also active during the last glacial period. It also provides a new framework for refining the exploration of these unique environments

    Franchise Business Development Model: Theoretical Considerations

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    Franchising is not a popular business development form in Lithuania. Only 0.02% of all Lithuanian companies use franchising for business development, while in most of the developed countries franchise is recognized as a convenient business expansion form. So, what factors determine such differences in the use of franchising? Analysis of related literature showed, that mainly researchers analyse some aspects of franchising, however there is no systematized analysis which covers all the main franchise development elements. Therefore, the aim of this article is to systematize franchise business development phases, main elements and factors, influencing this process and to propose a theoretical franchise system development model. Thus, theoretical considerations about the main phases and elements of franchise system development as well as advantages and disadvantages of the system are analysed in the article. These theoretical considerations are generalized in theoretical franchise system development model, which shows, that development of franchise business consists of particular steps, starting from favourable conditions for the system to emerge; intention and ability of franchisor to form franchise based on his business; the establishment and initial development of franchise system; and its further functioning. The article does not test the model and even does not discuss the operationalization of it. Operationalization of the model as well as empirical evidence is presented by the authors in the forthcoming articles

    Androgen-regulated transcription of ESRP2 drives alternative splicing patterns in prostate cancer

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    Prostate is the most frequent cancer in men. Prostate cancer progression is driven by androgen steroid hormones, and delayed by androgen deprivation therapy (ADT). Androgens control transcription by stimulating androgen receptor (AR) activity, yet also control pre-mRNA splicing through less clear mechanisms. Here we find androgens regulate splicing through AR-mediated transcriptional control of the epithelial-specific splicing regulator ESRP2. Both ESRP2 and its close paralog ESRP1 are highly expressed in primary prostate cancer. Androgen stimulation induces splicing switches in many endogenous ESRP2-controlled mRNA isoforms, including splicing switches correlating with disease progression. ESRP2 expression in clinical prostate cancer is repressed by ADT, which may thus inadvertently dampen epithelial splice programmes. Supporting this, treatment with the AR antagonist bicalutamide (Casodex) induced mesenchymal splicing patterns of genes including FLNB and CTNND1. Our data reveals a new mechanism of splicing control in prostate cancer with important implications for disease progression.This article is freely available via Open Access. Click on the Publisher URL to access the full-text via the publisher's site

    Lucro líquido do franqueado: um sinal para a escolha de franquia em época de crise

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    Este artículo aborda desde la perspectiva de la Teoría de Señales la elección de una franquicia por un potencial franquiciado que elige este canal de distribución por primera vez. El objetivo es analizar la relación entre algunas señales enviadas por el franquiciador y la elección de una franquicia por el potencial franquiciado. Concluimos que los efectos de las variables macroeconómicas de España en el periodo 2006-2013 influyeron en los ingresos netos de los franquiciados para que se convirtiera en una señal empleada por éstos a la hora de elegir la franquicia donde abrir un establecimiento.This paper adopts the perspective of Theory of Signals to discuss how someone starting a business as a franchisee for the first time can choose a suitable franchise brand. The aim was to analyze the relationship between certain signals sent by the franchisor and the choice of a franchise brand by the prospective franchisee. Using panel data, we found that the effects of macroeconomic variables in Spain for the 2006-2013 crisis period influenced franchisees' net income, which thus became a relevant signal in their process of choosing a franchise brand to start a business.Sob a perspectiva da Teoria de Sinais, este artigo aborda a seleção de uma franquia por um franqueado que elege esse potencial canal de distribuição pela primeira vez. O objetivo é analisar a relação entre alguns sinais enviados pelo franqueador e a escolha de uma franquia pelo potencial franqueado. Usando a metodologia de dados em painel, os resultados obtidos nos permitiram concluir que os efeitos das variáveis macroeconômicas da Espanha no período de crise econômica (2006-2013) influenciaram as receitas líquidas dos franqueados, tornando-se um sinal para eles elegerem onde abrir um estabelecimento franqueado

    Identificación y análisis de los recursos económicos asignados a la segunda locomotora. Evolución, aciertos y desaciertos

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    Con la elaboración del presente documento, se pretende identificar y analizar los recursos económicos asignados a una de las locomotoras del gobierno del presidente Juan Manuel Santos en el marco de su plan de desarrollo Prosperidad para todos y el impacto social de esta asignación de recursos en el agro Colombiano, Así mismo evaluar el cumplimiento de dicha política publica y la generación de bienestar social en la población."With the production of the present document, one tries to identify and to analyze the economic resources assigned to one of the locomotives of the government of the president Juan Manuel Santos in the frame of his plan of development "" Prosperity for all "" and the social impact of this assignment of resources in the Colombian agro, Likewise to evaluate the fulfillment of the above mentioned politics publishes and the generation of social well-being in the population.

    First evidence for a late LGM subglacial lake in Pine Island Bay, Antarctica

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    Subglacial lakes are widespread beneath the Antarctic Ice Sheet and as a source for subglacial meltwater they are assumed to modulate ice stream velocity. Further, the evacuation of subglacial meltwater at the ice sheet margin influences ocean circulation and geochemical cycles. However, despite their importance„ subglacial lakes are one of the least explored environments on our planet. As a consequence, their importance for ice sheet dynamics and their ability to harbour life remain poorly characterised. We present the first direct evidence for a palaeo-subglacial lake on the Antarctic continental shelf, document- ing that subglacial meltwater was stored during the last glacial period and evacuated during the subsequent deglaciation. A distinct sediment facies observed in a core recovered from a small bedrock basin in Pine Island Bay, Amundsen Sea, is indicative of deposition within a low-energy subglacial lake setting. Diffusive modelling demonstrates that low chloride concentrations in the pore water of this characteristic sediment facies can only be explained by original deposition in a freshwater setting. We also show that the location of the subglacial lake within a basin on the inner shelf is consistent with the predicted distribution of subglacial lakes based on bathymetric data. This finding will enable future modelling studies to investigate how the geometry and capacity of subglacial lake systems can influence ice dynamics when the substrate and profile of the ice sheet is known – especially in the highly sensitive area known as the "weak underbelly" of the WAIS. With the exception of a direct lake water access at Subglacial Lake Vostok, and some centimetres of sediment retrieval from Subglacial Lake Whillans, the subglacial hydrological system in Antarctica has hitherto mostly been explored using remote sensing and numerical models that suggest the number of potential lake sites to more than 12.000. Our study not only provides first empirical evidence for a palaeo-subglacial lake but also delivers a framework for investigating and refining exploration of these unique subglacial lake environments and their sediments beneath thick contemporary ice sheets. Our approach, however, is easier and cheaper to conduct by using ship borne coring equipment on the seasonal ice-free continental shelf

    Prototype ATLAS IBL Modules using the FE-I4A Front-End Readout Chip

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    The ATLAS Collaboration will upgrade its semiconductor pixel tracking detector with a new Insertable B-layer (IBL) between the existing pixel detector and the vacuum pipe of the Large Hadron Collider. The extreme operating conditions at this location have necessitated the development of new radiation hard pixel sensor technologies and a new front-end readout chip, called the FE-I4. Planar pixel sensors and 3D pixel sensors have been investigated to equip this new pixel layer, and prototype modules using the FE-I4A have been fabricated and characterized using 120 GeV pions at the CERN SPS and 4 GeV positrons at DESY, before and after module irradiation. Beam test results are presented, including charge collection efficiency, tracking efficiency and charge sharing.Comment: 45 pages, 30 figures, submitted to JINS
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