301 research outputs found

    The effect of different compost applications in organic production of lettuce (Lactuca sativa L.)

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    It is well-known that compost and manure applications to all kinds of soils if these organic materials are mature and composted under favorable conditions result in improved soil fertility and crop production in terms of yield and quality, but because manure is expensive in our region and the application of in-farm production compost for organic lands and farms of Turkey is limited, there is a great and urgent need for demonstrate compost using advantages to soil fertility, plant yield-quality and food safety (Kir 2006). Vegetables account for only approximately 2% of total organic production in Turkey, but there is great potential for growth of organic production for both export and domestic consumption of organic products in our country. Lettuce (Lactuca sativa L.) is one of the most important species for testing effects of compost applications because of its sensitivity related with phyto-toxic effects of compost (Fuchs et al. 2008) and very important to find out productivity and sustainable production levels in crop production. It is obtained from the results at the end of the first two-year trials, respectively of the three year-planned research under organic management (framework of regulations of EU and Turkey) that (1) the artificial organic materials sourced from farms can be composted and applied to lettuce production to get a great profit in terms of environment and economic aspects of organic lettuce production significantly, (2) promising improvement of industry of compost production can be expected, (3) Organic lettuce can be consumed as microbiologically safe, (4) high quality lettuce production can be attained by using compost

    Optical Resonators and Dynamic Maps

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    Investigation of conduction band structure, electron scattering mechanisms and phase transitions in indium selenide by means of transport measurements under pressure

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    In this work we report on Hall effect, resistivity and thermopower measurements in n-type indium selenide at room temperature under either hydrostatic and quasi-hydrostatic pressure. Up to 40 kbar (= 4 GPa), the decrease of carrier concentration as the pressure increases is explained through the existence of a subsidiary minimum in the conduction band. This minimum shifts towards lower energies under pressure, with a pressure coefficient of about -105 meV/GPa, and its related impurity level traps electrons as it reaches the band gap and approaches the Fermi level. The pressure value at which the electron trapping starts is shown to depend on the electron concentration at ambient pressure and the dimensionality of the electron gas. At low pressures the electron mobility increases under pressure for both 3D and 2D electrons, the increase rate being higher for 2D electrons, which is shown to be coherent with previous scattering mechanisms models. The phase transition from the semiconductor layered phase to the metallic sodium cloride phase is observed as a drop in resistivity around 105 kbar, but above 40 kbar a sharp nonreversible increase of the carrier concentration is observed, which is attributed to the formation of donor defects as precursors of the phase transition.Comment: 18 pages, Latex, 10 postscript figure

    The influence of the political environment and destination governance on sustainable tourism development: a study of Bled, Slovenia

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    In the context of sustainable tourism development, there are many studies about the exchange process between residents and tourism, yet this issue is practically unexplored with respect to the political environment of tourism. Therefore, this paper introduces and posits that the political environment is a necessary enabler for implementing sustainable tourism. The authors extend the established three-pillar sustainability concept by adding in the political dimension. Then they surveyed how residents' positive and negative perceptions of tourism impacts determine their satisfaction with life in the tourism destination and thus their support for tourism in their community. The model was empirically tested within the context of the long-established Alpine destination of Bled in Slovenia. The findings confirm the importance of the political environment and question the sustainability of Bled's tourism development. It is suggested that the community has relatively weak destination governance due to the underdeveloped political environment. The survey expands and deepens the tourism sustainability debate by adding in the political environment and how it relates to the emerging growth of research on destination governance. The proposed model can be adapted and applied to any destination in order to improve its governance, including the implementation of sustainable tourism development

    DAVID Bioinformatics Resources: expanded annotation database and novel algorithms to better extract biology from large gene lists

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    All tools in the DAVID Bioinformatics Resources aim to provide functional interpretation of large lists of genes derived from genomic studies. The newly updated DAVID Bioinformatics Resources consists of the DAVID Knowledgebase and five integrated, web-based functional annotation tool suites: the DAVID Gene Functional Classification Tool, the DAVID Functional Annotation Tool, the DAVID Gene ID Conversion Tool, the DAVID Gene Name Viewer and the DAVID NIAID Pathogen Genome Browser. The expanded DAVID Knowledgebase now integrates almost all major and well-known public bioinformatics resources centralized by the DAVID Gene Concept, a single-linkage method to agglomerate tens of millions of diverse gene/protein identifiers and annotation terms from a variety of public bioinformatics databases. For any uploaded gene list, the DAVID Resources now provides not only the typical gene-term enrichment analysis, but also new tools and functions that allow users to condense large gene lists into gene functional groups, convert between gene/protein identifiers, visualize many-genes-to-many-terms relationships, cluster redundant and heterogeneous terms into groups, search for interesting and related genes or terms, dynamically view genes from their lists on bio-pathways and more. With DAVID (http://david.niaid.nih.gov), investigators gain more power to interpret the biological mechanisms associated with large gene lists

    Validation of a contemporary prostate cancer grading system using prostate cancer death as outcome

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    BACKGROUND: Gleason scoring (GS) has major deficiencies and a novel system of five grade groups (GS⩽6; 3+4; 4+3; 8; ⩾9) has been recently agreed and included in the WHO 2016 classification. Although verified in radical prostatectomies using PSA relapse for outcome, it has not been validated using prostate cancer death as an outcome in biopsy series. There is debate whether an ‘overall' or ‘worst' GS in biopsies series should be used. METHODS: Nine hundred and eighty-eight prostate cancer biopsy cases were identified between 1990 and 2003, and treated conservatively. Diagnosis and grade was assigned to each core as well as an overall grade. Follow-up for prostate cancer death was until 31 December 2012. A log-rank test assessed univariable differences between the five grade groups based on overall and worst grade seen, and using univariable and multivariable Cox proportional hazards. Regression was used to quantify differences in outcome. RESULTS: Using both ‘worst' and ‘overall' GS yielded highly significant results on univariate and multivariate analysis with overall GS slightly but insignificantly outperforming worst GS. There was a strong correlation with the five grade groups and prostate cancer death. CONCLUSIONS: This is the largest conservatively treated prostate cancer cohort with long-term follow-up and contemporary assessment of grade. It validates the formation of five grade groups and suggests that the ‘worst' grade is a valid prognostic measure

    The transcriptional activity of hepatocyte nuclear factor 4 alpha is inhibited via phosphorylation by ERK1/2

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    Hepatocyte nuclear factor 4 alpha (HNF4alpha) nuclear receptor is a master regulator of hepatocyte development, nutrient transport and metabolism. HNF4alpha is regulated both at the transcriptional and post-transcriptional levels by different mechanisms. Several kinases (PKA, PKC, AMPK) were shown to phosphorylate and decrease the activity of HNF4alpha. Activation of the ERK1/2 signalling pathway, inducing proliferation and survival, inhibits the expression of HNF4alpha. However, based on our previous results we hypothesized that HNF4alpha is also regulated at the post-transcriptional level by ERK1/2. Here we show that ERK1/2 is capable of directly phosphorylating HNF4alpha in vitro at several phosphorylation sites including residues previously shown to be targeted by other kinases, as well. Furthermore, we also demonstrate that phosphorylation of HNF4alpha leads to a reduced trans-activational capacity of the nuclear receptor in luciferase reporter gene assay. We confirm the functional relevance of these findings by demonstrating with ChIP-qPCR experiments that 30-minute activation of ERK1/2 leads to reduced chromatin binding of HNF4alpha. Accordingly, we have observed decreasing but not disappearing binding of HNF4alpha to the target genes. In addition, 24-hour activation of the pathway further decreased HNF4alpha chromatin binding to specific loci in ChIP-qPCR experiments, which confirms the previous reports on the decreased expression of the HNF4a gene due to ERK1/2 activation. Our data suggest that the ERK1/2 pathway plays an important role in the regulation of HNF4alpha-dependent hepatic gene expression

    Resveratrol and Cancer: Focus on in vivo Evidence

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    Resveratrol is a naturally occurring polyphenol that provides a number of anti-aging health benefits including improved metabolism, cardioprotection, and cancer prevention. Much of the work on resveratrol and cancer comes from in vitro studies looking at resveratrol actions on cancer cells and pathways. There are, however, comparatively fewer studies that have investigated resveratrol treatment and cancer outcomes in vivo, perhaps limited by its poor bioavailability when taken orally. Although research in cell culture has shown promising and positive effects of resveratrol, evidence from rodents and humans is inconsistent. This review highlights the in vivo effects of resveratrol treatment on breast, colorectal, liver, pancreatic, and prostate cancers. Resveratrol supplementation in animal models of cancer has shown positive, neutral as well as negative outcomes depending on resveratrol route of administration, dose, tumor model, species, and other factors. Within a specific cancer type, there is variability between studies with respect to strain, age, and sex of animal used, timing and method of resveratrol supplementation, and dose of resveratrol used to study cancer endpoints. Together, the data suggest that many factors need to be considered before resveratrol can be used for human cancer prevention or therapy
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