35 research outputs found

    Data Descriptor : A European Multi Lake Survey dataset of environmental variables, phytoplankton pigments and cyanotoxins

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    Under ongoing climate change and increasing anthropogenic activity, which continuously challenge ecosystem resilience, an in-depth understanding of ecological processes is urgently needed. Lakes, as providers of numerous ecosystem services, face multiple stressors that threaten their functioning. Harmful cyanobacterial blooms are a persistent problem resulting from nutrient pollution and climate-change induced stressors, like poor transparency, increased water temperature and enhanced stratification. Consistency in data collection and analysis methods is necessary to achieve fully comparable datasets and for statistical validity, avoiding issues linked to disparate data sources. The European Multi Lake Survey (EMLS) in summer 2015 was an initiative among scientists from 27 countries to collect and analyse lake physical, chemical and biological variables in a fully standardized manner. This database includes in-situ lake variables along with nutrient, pigment and cyanotoxin data of 369 lakes in Europe, which were centrally analysed in dedicated laboratories. Publishing the EMLS methods and dataset might inspire similar initiatives to study across large geographic areas that will contribute to better understanding lake responses in a changing environment.Peer reviewe

    A European Multi Lake Survey dataset of environmental variables, phytoplankton pigments and cyanotoxins

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    Temperature Effects Explain Continental Scale Distribution of Cyanobacterial Toxins

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    Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their potency. Most studies examine the relationship between individual toxin variants and environmental factors, such as nutrients, temperature and light. In summer 2015, we collected samples across Europe to investigate the effect of nutrient and temperature gradients on the variability of toxin production at a continental scale. Direct and indirect effects of temperature were the main drivers of the spatial distribution in the toxins produced by the cyanobacterial community, the toxin concentrations and toxin quota. Generalized linear models showed that a Toxin Diversity Index (TDI) increased with latitude, while it decreased with water stability. Increases in TDI were explained through a significant increase in toxin variants such as MC-YR, anatoxin and cylindrospermopsin, accompanied by a decreasing presence of MC-LR. While global warming continues, the direct and indirect effects of increased lake temperatures will drive changes in the distribution of cyanobacterial toxins in Europe, potentially promoting selection of a few highly toxic species or strains.Peer reviewe

    Measurement of angular dependence of M X-ray production cross-sections in Re, Bi and U at 5.96 keV

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    The M X-ray production differential cross sections in Re, Bi and U elements have been measured at the 5.96 keV incident photon energy in an angular range 135°–155°. The measurements were performed using a 55Fe source and a Si(Li) detector. The present results contradict the predictions of Cooper and Zare [Atomic Collision Processes, Gordon and Breach, New York (1969)] and experimental results of Kumar et al. [J. Phys. B: At. Mol. Opt. 34, 613 (2001)]. that, after photoionization of inner shells, the vacancy state has equal population of magnetic substates and the subsequent X-ray emission is isotropic, but confirm the predictions of the calculations of Flügge et al. [Phys. Rev. Lett. 29, 7 (1972)] and experimental results of Sharma and Allawadhi [J. Phys. B: At. Mol. Opt. 32, 2343 (1999)] and Ertugrul [Nucl. Instrum. Meth. B 119, 345 (1996)]. Total M X-ray production cross sections from the decay at the 5.96 keV photon energies are found to be in good agreement with the calculated theoretical results using the theoretical values of M shell photoionization cross section

    Examination of the change of the characteristic X-rays of the zinc in fluorine- and boron-doped ZnO thin films

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    In this study, K_{β}/K_{α} X-ray intensity ratios of zinc in pure zinc, undoped ZnO thin film and boron and fluorine-doped ZnO thin films have been investigated. These samples have been excited by 59.5 keV γ-rays from a ^{241}Am annular radioactive source. K X-rays emitted by the samples have been counted using an Ultra-LEGe detector with a resolution of 150 eV at 5.9 keV. The K_{β}/K_{α} X-ray intensity ratios of the doped ZnO thin films have been compared with that of the undoped ZnO thin film. The deviations between the results can be explained by delocalization and/or charge transfer phenomena causing change in valence electronic configuration of zinc

    Chemical effects on the K

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    Chemical effects on the Kβ/Kα X-ray intensity ratios for some Mn, Ni, and Cu complexes of a new schiff-base with salen N2H2 type were investigated. The samples were excited by 59.543 keV γ-rays from a 241Am annular radioactive source. K X-rays emitted by samples were counted by a Si(Li) detector with resolution 157 eV at 5.9 keV. We observed the chemical effect on the Kβ/Kα X-ray intensity ratios for Mn, Ni and Cu complexes. The experimental results showed that the Kβ/Kα X-ray intensity ratios for compounds with complexes are generally larger than those with salt form. The experimental values have been compared with the other experimental and the theoretically calculated values of pure elements. The results are in very good agreement with the others

    Outcomes of vaginal hysterectomy and constricting colporrhaphy with concurrent levator myorrhaphy and high perineorrhaphy in women older than 75 years of age

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    Emrah Töz, Aykut Özcan, Nesin Apaydin, İbrahim Uyar, Betül Kocakaya, Gülin Okay Department of Gynecology and Obstetrics, Tepecik Education and Research Hospital, İzmir, Turkey Objectives: We performed constricting anterior and posterior colporrhaphy, levator myorrhaphy, and high perineorrhaphy with concurrent hysterectomy, and investigated the intraoperative complications, and short-term outcomes of these constricting procedures in patients aged 75 years or older.Methods: We searched our hospital database for cases, between January 2011 and January 2014, of women aged over 75 years who underwent surgery for pelvic organ prolapse of stage 2 or higher, via vaginal hysterectomy, constricting anterior and posterior colporrhaphy, levator myorrhaphy, and high perineorrhaphy, with or without treatment of urinary incontinence. All volunteers were evaluated via pelvic examination using the pelvic organ prolapse quantification system, the modified Decision Regret Scale–Pelvic Floor Disorders form, the Satisfaction Decision Scale–Pelvic Floor Disorders form, and the Pelvic Floor Distress Inventory form.Results: Fifty-four patients were included in the study. The mean follow-up time was 24.4 months after constricting surgery (range: 8–44 months). There were four cases (7%) of de novo urge incontinence (the symptoms resolved upon prescription of anticholinergic medication). Two patients developed de novo stress urinary incontinence after the procedure and were treated via transobturator sling surgery using Safyre T® polypropylene monofilament slings. No anatomical or subjective recurrence of prolapse was noted during the follow-up period. No patient required additional surgery for recurrence of prolapse.Conclusion: Constricting anterior and posterior colporrhaphy, levator myorrhaphy, and high perineorrhaphy with concurrent hysterectomy is a feasible, safe, and effective surgical option in elderly patients at low anesthesiological risk. The decision to perform an incontinence procedure should be individualized based on preoperative findings after prolapse reduction. Keywords: older women, pelvic organ prolapse, constrictive surgical procedures, urinary incontinenc
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