1,835 research outputs found

    Authority arguments in academic contexts in social studies and humanities

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    In academic contexts the appeal to authority is a quite common but seldom tested argument, either because we accept the authority without questioning it, or because we look for alternative experts or reasons to support a different point of view. But, by putting ourselves side by side an already accepted authority, we often rhetorically manoeuvre to displace the burden of the proof to avoid the fear to present our opinions and to allow face saving

    Biotreatment of industrial wastewaters under transient-state conditions: process stability with fluctuations of organic load, substrates, toxicants, and environmental parameters

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    Biotreatment of industrial wastewater is often challenged by operation under transient states with respect to organic loads, pollutants, and physical characteristics. Furthermore, the potential presence of inhibitory compounds requires careful monitoring and adequate process design. This review describes difficulties encountered in biological treatment of wastewater with highly variable influent characteristics. Typical design aspects of biological processes are presented and discussed with respect to their success in treating highly fluctuating wastewaters. In general, biomass retention is a key factor for dealing with highly fluctuating and/or inhibitory wastewater, but the how it operates also affects the stability of performance, as it was shown that dynamic operation instead of operation at a constant flow enhances biodegradation onset and more evenly distributed activity. Although ultimately stable effluent quality must be achieved, the microbial population stability is not necessarily high, as it was shown that microbial diversity and flexibility may play a critical role in functional stability.info:eu-repo/semantics/acceptedVersio

    Spectrophotometric Observations of Blue Compact Dwarf Galaxies: Mrk 370

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    We present results from a detailed spectrophotometric analysis of the blue compact dwarf galaxy (BCD) Mrk 370, based on deep UBVRI broad-band and Halpha narrow-band observations, and long-slit and two-dimensional spectroscopy of its brightest knots. The spectroscopic data are used to derive the internal extinction, and to compute metallicities, electronic density and temperature in the knots. By subtracting the contribution of the underlying older stellar population, modeled by an exponential function, removing the contribution from emission lines, and correcting for extinction, we can measure the true colors of the young star-forming knots. We show that the colors obtained this way differ significantly from those derived without the above corrections, and lead to different estimates of the ages and star-forming history of the knots. Using predictions of evolutionary synthesis models, we estimate the ages of both the starburst regions and the underlying stellar component. We found that we can reproduce the colors of all the knots with an instantaneous burst of star formation and the Salpeter initial mass function with an upper mass limit of 100 solar masses. The resulting ages range between 3 and 6 Myrs. The colors of the low surface brightness component are consistent with ages larger than 5 Gyr. The kinematic results suggest ordered motion around the major axis of the galaxy.Comment: 26 pages with 14 figures; accepted for publication in Ap

    27. New echocardiogram index alternatives to MAPSE and TAPSE z-scores in children

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    BackgroundMitral annular plane systolic excursion (MAPSE), and tricuspid annular plane systolic excursion (TAPSE) are relatively load independent longitudinal left ventricle (LV) and right ventricle (RV) measurement in both adults and children. Normal paediatric values of MAPSE and TAPSE unlike adults are based on inconvenient z-scores. We hypothesize novel indexes of (LSI) LV longitudinal systolic index and (RSI) RV longitudinal systolic index are BSA, age, gender independent and nullifies the need for MAPSE and TAPSE z-scores.MethodsNormal echocardiograms were retrospectively reviewed from 2009 to 2011. Ejection fraction, LV dimensions, MAPSE, and TAPSE were determined. LSI and RSI were calculated using MAPSE and TAPSE divided by LV length. Echocardiogram indices were correlated. Regression analysis was done for BSA, age, and gender.ResultsTwo hundred and one patients had normal ejection fractions (67.3;±5.1%). Mean MAPSE 10.4;±3.3mm, z-score −0.07;±1.2, and LSI 0.20;±0.03; Mean TAPSE 17.4;±5.4mm, z-score 0.74;±1.7, and RSI 0.34;±0.06. LSI and MAPSE z-scores correlated, r=0.73, p<0.001. Age, gender, and BSA did not correlate with LSI. RSI and TAPSE z-scores correlated with r=0.76, p<0.001. Age influences RSI, R2=0.58, p value <0.001, BSA and gender does not. RSI, with age stratification, is significantly decreased less than 2months.ConclusionLSI obviates need for-MAPSE z scores. RSI offers an additional non TAPSE z-score method to evaluate RV function, but does not nullify age effect. RSI, especially in the first two months is decreased

    Kinetics of Plasma- and Erythrocyte-Astaxanthin in Healthy Subjects Following a Single and Maintenance Oral Dose

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    Aim & background: Astaxanthin is a unique carotenoid of predominantly marine origin providing the pink-red color to certain microalgae and accumulating in various animals higher in the food chain. It is an antioxidant without pro-oxidant properties or known side-effects following oral intake. Methods: We investigated astaxanthin kinetics in plasma and erythrocytes (RBC) of four healthy adults after a single oral 40 mg dose. Plasma- and RBC-astaxanthin were measured during 72h. Subsequently, an 8 mg/day dose was given during 17 days. Plasma- and RBC-astaxanthin were measured each morning. Results: Plasmaastaxanthin reached a peak (from 79 to 315 nmol/L) after 8h and then declined (half-life, 18h). Within 72h, plasma-astaxanthin had returned to baseline. RBC-astaxanthin reached a peak (from 63 to 137 nmol/L packed cells) at 12h and subsequently disappeared (half-life, 28h). During the daily dose, plasmaastaxanthin increased until day 10 (187 nmol/L) and then decreased to a steady concentration similar to that reached after 2 days. RBC-astaxanthin appeared to be highly variable (group median concentration, 86 nmol/L packed cells). Conclusion: We found high intra- and inter-individual variations, especially in RBC, possibly due to non-standardized time difference between astaxanthin intake and sampling, fl uctuating background intake from the diet, variable bioavailability, large distribution volume, degradation or others. Oral astaxanthin is rapidly absorbed and incorporated into RBC. The subsequent rapid decline suggests that, for a higher-than-baseline status, astaxanthin should be taken daily, at least in an early phase when total body equilibrium, if any, has not been reached yet

    Deep Near Infrared Mapping of Young and Old Stars in Blue Compact Dwarf Galaxies

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    We analyze J, H and Ks near-infrared data for 9 Blue Compact Dwarf (BCD) galaxies, selected from a larger sample that we have already studied in the optical. We present contour maps, surface brightness and color profiles, as well as color maps of the sample galaxies. The morphology of the BCDs in the NIR has been found to be basically the same as in the optical. The inner regions of these systems are dominated by the starburst component. At low surface brightness levels the emission is due to the underlying host galaxy; the latter is characterized by red, radially constant colors and isophotes well fit by ellipses. We derive accurate optical near--infrared host galaxy colors for eight of the sample galaxies; these colors are typical of an evolved stellar population. Interestingly, optical near--infrared color maps reveal the presence of a complex, large-scale absorption pattern in three of the sample galaxies. We study the applicability of the Sersic law to describe the surface brightness profiles of the underlying host galaxy, and find that, because of the limited surface brightness interval over which the fit can be made, the derived Sersic parameters are very sensitive to the selected radial interval and to errors in the sky subtraction. Fitting an exponential model gives generally more stable results, and can provide a useful tool to quantify the structural properties of the host galaxy and compare them with those of other dwarf classes as well as with those of star-forming dwarfs at higher redshifts.Comment: 49 pages, 9 figures, 10 tables, accepted for publication in the Astrophysical Journa

    Analytical techniques for multiplex analysis of protein biomarkers

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    Introduction: The importance of biomarkers for pharmaceutical drug development and clinical diagnostics is more significant than ever in the current shift toward personalized medicine. Biomarkers have taken a central position either as companion markers to support drug development and patient selection, or as indicators aiming to detect the earliest perturbations indicative of disease, minimizing therapeutic intervention or even enabling disease reversal. Protein biomarkers are of particular interest given their central role in biochemical pathways. Hence, capabilities to analyze multiple protein biomarkers in one assay are highly interesting for biomedical research. Areas covered: We here review multiple methods that are suitable for robust, high throughput, standardized, and affordable analysis of protein biomarkers in a multiplex format. We describe innovative developments in immunoassays, the vanguard of methods in clinical laboratories, and mass spectrometry, increasingly implemented for protein biomarker analysis. Moreover, emerging techniques are discussed with potentially improved protein capture, separation, and detection that will further boost multiplex analyses. Expert commentary: The development of clinically applied multiplex protein biomarker assays is essential as multi-protein signatures provide more comprehensive information about biological systems than single biomarkers, leading to improved insights in mechanisms of disease, diagnostics, and the effect of personalized medicine

    Large-Scale Meta-GWAS Reveals Common Genetic Factors Linked to Radiation-Induced Acute Toxicities across Cancers

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    BACKGROUND: This study was designed to identify common genetic susceptibility and shared genetic variants associated with acute radiation-induced toxicity (RIT) across four cancer types (prostate, head and neck, breast, and lung).METHODS: A GWAS meta-analysis was performed using 19 cohorts including 12,042 patients. Acute standardized total average toxicity (rSTATacute) was modelled using a generalized linear regression model for additive effect of genetic variants adjusted for demographic and clinical covariates. LD score regression estimated shared SNP-based heritability of rSTATacute in all patients and for each cancer type.RESULTS: Shared SNP-based heritability of STATacute among all cancer types was estimated at 10% (se = 0.02), and was higher for prostate (17%, se = 0.07), head and neck (27%, se = 0.09), and breast (16%, se = 0.09) cancers. We identified 130 suggestive associated SNPs with rSTATacute (5.0x10-8&lt;P-value&lt;1.0x10-5) across 25 genomic regions. rs142667902 showed the strongest association (effect allele A; effect size -0.17; P-value=1.7x10-7), which is located near DPPA4, encoding a protein involved in pluripotency in stem cells, which are essential for repair of radiation-induced tissue injury. Gene-set enrichment analysis identified 'RNA splicing via endonucleolytic cleavage and ligation' (P = 5.1 x10-6, Pcorrected =0.079) as the top gene set associated with rSTATacute among all patients. In-silico gene expression analysis showed the genes associated with rSTATacute were statistically significantly up-regulated in skin (not sun exposed Pcorrected=0.004; sun exposed Pcorrected=0.026).CONCLUSIONS: There is shared SNP-based heritability for acute RIT across and within individual cancer sites. Future meta-GWAS among large radiotherapy patient cohorts are worthwhile to identify the common causal variants for acute radiotoxicity across cancer types.</p

    SerpinA3N is a novel hypothalamic gene upregulated by a high-fat diet and leptin in mice

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    Background: Energy homeostasis is regulated by the hypothalamus but fails when animals are fed a high-fat diet (HFD), and leptin insensitivity and obesity develops. To elucidate the possible mechanisms underlying these effects, a microarray-based transcriptomics approach was used to identify novel genes regulated by HFD and leptin in the mouse hypothalamus. Results: Mouse global array data identified serpinA3N as a novel gene highly upregulated by both a HFD and leptin challenge. In situ hybridisation showed serpinA3N expression upregulation by HFD and leptin in all major hypothalamic nuclei in agreement with transcriptomic gene expression data. Immunohistochemistry and studies in the hypothalamic clonal neuronal cell line, mHypoE-N42 (N42), confirmed that alpha 1-antichymotrypsin (α1AC), the protein encoded by serpinA3, is localised to neurons and revealed that it is secreted into the media. SerpinA3N expression in N42 neurons is upregulated by palmitic acid and by leptin, together with IL-6 and TNFα, and all three genes are downregulated by the anti-inflammatory monounsaturated fat, oleic acid. Additionally, palmitate upregulation of serpinA3 in N42 neurons is blocked by the NFκB inhibitor, BAY11, and the upregulation of serpinA3N expression in the hypothalamus by HFD is blunted in IL-1 receptor 1 knockout (IL-1R1−/−) mice. Conclusions: These data demonstrate that serpinA3 expression is implicated in nutritionally mediated hypothalamic inflammation
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