336 research outputs found

    Designing short term trading systems with artificial neural networks

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    Phosphorus bioavailability in soil profiles of a long-term fertilizer experiment: The evaluation of their bioaccessibility

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    Global agricultural productivity depends on the use of finite phosphorus (P) resources of which not only the topsoil, but also subsoil, can hold immense reserves. To assess potential soil contribution to plant nutrition, we compared the P status of Stagnic Cambisol profiles in experimental plots that received different P fertilizer applications (control, triple superphosphate (TSP), compost, compost+TSP) for 16 years. Sequential fractionation was combined with P K-edge X-ray absorption near edge structure (XANES) spectroscopy to identify the chemical P speciation. Fertilized topsoils (21 to 69 kg P ha-1 a-1) showed P reserves larger by a factor of 1.2 to 1.4, and subsoil P reserves larger by a factor of 1.3 to 1.5 than those of the control. P-XANES revealed the predominance of inorganic P species such as moderately labile Fe- (46 to 92%), Al- (0 to 40%), and Ca- (0 to 15%) P compounds besides organic P (0 to 13%) in all treatments. The fertilizer application slightly altered P speciation throughout the profiles, but the type of fertilizer had no significant effect on it. Optimal plant growth requirements are restricted by the exchangeable P from the solid phase within the soil solution. Therefore, ongoing research focuses on the accessibility of P from P loaded amorphous Fe- and Al-hydroxides, previously identified as the predominant abiotic P forms. To assess their P desorption potential, P-33 rhizotron experiments combined with P-33 isotopic exchange kinetics (IEK) are underway. Preliminary results indicated that besides differences in P binding capacity of soil hydroxides, physical soil parameters, such as the matric potential, strongly control soil P availability, thus plant P acquisition rates can vary among different soil types. Our results gained new detailed information about P bioavailability under agricultural practice. The investigations towards P bioaccessibility may contribute to improved interpretation of soil P tests and reduced fertilizer recommendations

    Rapid and complete paraffin removal from human tissue sections delivers enhanced Raman spectroscopic and histopathological analysis

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    Incomplete removal of paraffin and organic contaminants from tissues processed for diagnostic histology has been a profound barrier to the introduction of Raman spectroscopic techniques into clinical practice. We report a route to rapid and complete paraffin removal from a range of formalin-fixed paraffin embedded tissues using super mirror stainless steel slides. The method is equally effective on a range of human and animal tissues, performs equally well with archived and new samples and is compatible with standard pathology lab procedures. We describe a general enhancement of the Raman scatter and enhanced staining with antibodies used in immunohistochemistry for clinical diagnosis. We conclude that these novel slide substrates have the power to improve diagnosis through anatomical pathology by facilitating the simultaneous combination of improved, more sensitive immunohistochemical staining and simplified, more reliable Raman spectroscopic imaging, analysis and signal processing

    Alternative tissue fixation for combined histopathological and molecular analysis in a clinically representative setting

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    Formalin is the principal tissue fixative used worldwide for clinical and research purposes. Despite optimal preservation of morphology, its preservation of DNA and RNA is poor. As clinical diagnostics increasingly incorporates molecular-based analysis, the requirement for maintaining nucleic acid quality is of increasing importance. Here we assess an alternative non-formalin-based tissue fixation method, PAXgene Tissue system, with the aim of better preserving nucleic acids, while maintaining the quality of the tissue to be used for vital existing diagnostic techniques. In this study, these criteria are assessed in a clinically representative setting. In total, 203 paired PAXgene Tissue and formalin-fixed samples were obtained. Blind-scored haematoxylin and eosin (H&E) sections showed comparable and acceptable staining. Immunohistochemistry (IHC) staining was suboptimal using existing protocols but improved with minor method adjustment and optimisation. Quality of DNA and RNA was significantly improved by PAXgene tissue fixation [RIN 2.8 versus 3.8 (p < 0.01), DIN 5.68 versus 6.77 (p < 0.001)], which translated into improved performance on qPCR assay. These results demonstrate the potential of PAXgene Tissue to be used routinely in place of formalin, maintaining adequate histological staining and significantly improving the preservation of biological molecules in the genomic era

    The fourteenth-century poll tax returns and the study of English surname distribution

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    The modern-day distributions of English surnames have been considered in genealogical, historical, and philological research as possible indicators of their origins. However, many centuries have passed since hereditary surnames were first used, and so their distribution today does not necessarily reflect their original spread, misrepresenting their origins. Previously, medieval data with national coverage have not been available for a study of surname distribution, but with the recent publication of the fourteenth-century poll tax returns, this has changed. By presenting discrepancies in medieval and nineteenth-century distributions, it is shown that more recent surname data may not be a suitable guide to surname origins and can be usefully supplemented by medieval data in order to arrive at more accurate conclusions

    ARID1A influences HDAC1/BRD4 activity, intrinsic proliferative capacity and breast cancer treatment response.

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    Using genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) screens to understand endocrine drug resistance, we discovered ARID1A and other SWI/SNF complex components as the factors most critically required for response to two classes of estrogen receptor-alpha (ER) antagonists. In this context, SWI/SNF-specific gene deletion resulted in drug resistance. Unexpectedly, ARID1A was also the top candidate in regard to response to the bromodomain and extraterminal domain inhibitor JQ1, but in the opposite direction, with loss of ARID1A sensitizing breast cancer cells to bromodomain and extraterminal domain inhibition. We show that ARID1A is a repressor that binds chromatin at ER cis-regulatory elements. However, ARID1A elicits repressive activity in an enhancer-specific, but forkhead box A1-dependent and active, ER-independent manner. Deletion of ARID1A resulted in loss of histone deacetylase 1 binding, increased histone 4 lysine acetylation and subsequent BRD4-driven transcription and growth. ARID1A mutations are more frequent in treatment-resistant disease, and our findings provide mechanistic insight into this process while revealing rational treatment strategies for these patients
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