Transport von Silbernanopartikeln in natürlich gelagerten Bodensäulen

Die Anzahl der wissenschaftlichen Untersuchungen zum Verbleib von Silbernanopartikeln (Ag-NP) in Böden hat in den letzten Jahren zugenommen. Da die publizierten Ergebnisse darauf hinweisen, dass sie stark durch die gewählten Versuchs- und Randbedingungen beeinflusst werden, bleibt die Bewertung der Mobilität von Silbernanopartikeln in Böden schwierig. Daher sollte der Transport und Verbleib der Ag-NP in dieser Untersuchung unter naturnahe Bedingung, aber mit kontrollierten Rand- und Anfangsbedingungen bestimmt werden. Dazu wurden an zwei Standorten (Sand, Schluff) jeweils acht ungestörte Bodensäulen (Ø 10,2 cm Höhe 16 cm) genommen und in einer Säulenversuchsanlage (SCS, Fa. emc GmbH) untersucht. Drei Säulen dienten jeweils als Parallelen während eine Säule als Kontrolle ohne Zugabe von NP untersucht wurde. Für beide Bodenarten erfolgten Versuche mit gesättigtem und ungesättigtem Fluss. Zur Nachverfolgung des Wasserflusses durch die Säulen wurde dem Beregnungswasser D2O als Tracer zugesetzt. Die Silbergesamtgehalte im Perkolat wurde nach HNO3-Aufschluss und mit ICP-OES/MS analysiert. Die Messung der gelösten Silberfraktion erfolgte nach Ultrazentrifugation mit ICP-MS. Die Größenverteilung von natürlichen Bodenkolloiden und Ag-NP wurde mit Dynamic Light Scattering (Malvern NanoZS) gemessen. Die Ergebnisse bestätigen den Einfluss der Versuchsbedingungen, zeigen aber auch die Bedeutung der Bodenstruktur auf die Mobilität der Ag-NP. Die Variabilität zwischen den Parallelproben ist sehr groß und überschattet mögliche Unterschiede zwischen den Bodenarten. Bevorzugte Fließwege sind wohl die Regel, die frühen Durchbrüche von D2O und Ag-NP bestätigt den präferentiellen Transport von Wasser und Partikeln. Mit Hilfe eines nachträglich durch die Säule perkolierten Farbstoffes (Brillant Blue) wurde Randfluss ausgeschlossen. Unter ungesättigten Bedingungen wird ein deutlich größerer Teil der Ag-NP im Boden zurückgehalten als unter gesättigten Fließbedingungen. Daher wird angenommen, dass die Bodenluft für die Retention der Partikel im Boden wichtig ist

Encoding Liturgical Chant Notations and Meta-Data

Summary of an invited panel discussion at the Music Encoding Conference 2022

Effect of rosuvastatin on outcomes in chronic haemodialysis patients – design and rationale of the AURORA study

BACKGROUND: Patients with end-stage renal disease (ESRD) are at high risk of cardiovascular events. Multiple risk factors for atherosclerosis are present in ESRD and may contribute to the increased risk of cardiovascular mortality in this population. In contrast to patients with normal renal function, the benefits of modifying lipid levels on cardiovascular outcomes in patients with ESRD on haemodialysis have yet to be confirmed in large prospective randomised trials. A study to evaluate the Use of Rosuvastatin in subjects On Regular haemodialysis: an Assessment of survival and cardiovascular events (AURORA) will be the first large-scale international trial to assess the effects of statin therapy on cardiovascular morbidity and mortality in ESRD patients on chronic haemodialysis. METHODS: More than 2,750 ESRD patients who have been receiving chronic haemodialysis treatment for at least 3 months have been randomised (1:1), irrespective of baseline lipid levels, to treatment with rosuvastatin 10 mg or placebo. The primary study endpoint is the time to a major cardiovascular event (first occurrence of cardiovascular death, non-fatal myocardial infarction or non-fatal stroke). Secondary endpoints include all-cause mortality, major cardiovascular event-free survival time, time to cardiovascular death, time to non-cardiovascular death, cardiovascular interventions, tolerability of treatment and health economic costs per life-year saved. Study medication will be given until 620 subjects have experienced a major cardiovascular event. CONCLUSION: Our hypothesis is that results from AURORA will establish the clinical efficacy and tolerability of rosuvastatin in patients with ESRD receiving chronic haemodialysis and guide the optimal management of this expanding population

Helicobacter pylori Adapts to Chronic Infection and Gastric Disease via pH-Responsive BabA-Mediated Adherence

International audienceThe BabA adhesin mediates high-affinity binding of Helicobacter pylori to the ABO blood group antigen-glycosylated gastric mucosa. Here we show that BabA is acid responsive-binding is reduced at low pH and restored by acid neutralization. Acid responsiveness differs among strains; often correlates with different intragastric regions and evolves during chronic infection and disease progression; and depends on pH sensor sequences in BabA and on pH reversible formation of high-affinity binding BabA multimers. We propose that BabA's extraordinary reversible acid responsiveness enables tight mucosal bacterial adherence while also allowing an effective escape from epithelial cells and mucus that are shed into the acidic bactericidal lumen and that bio-selection and changes in BabA binding properties through mutation and recombination with babA-related genes are selected by differences among individuals and by changes in gastric acidity over time. These processes generate diverse H. pylori subpopulations, in which BabA's adaptive evolution contributes to H. pylori persistence and overt gastric disease

Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

Reduction of photosynthesis in sun leaves of Gossypium hirsutum L under conditions of high light intensities and suboptimal leaf temperatures

Attached sun leaves of cotton (Gossypium hirsutum L var Delta Pine 61) were enclosed in a gas exchange cuvette and exposed for 4 d to either 1 000 or 1 800 μmol photons m-2s-1 and a series of air temperatures (35, 30, 25 and 20°C) during the 12-h light periods. The temperature during the 12-h dark periods was maintained at 25°C. The highest CO2 assimilation rates (Amax: ≈ 30 μmol CO2 m-2s-1) were reached at 1 800 μmol photons m-2s-1 and air temperatures of 30 and 35 °C. At 30 °C and 1 000 μmol photons m-2 s-1, Amax was reduced by 20%. At both light intensities Amax and stomatal conductance declined with decreasing temperatures. The reduction in Amax was most severe at 1 800 μmol photons m-2s-1 and 20°C. The leaves exposed to these conditions also exhibited marked decreases in rates of CO2 -saturated photosynthetic O2 evolution under light saturation (PSmax) and light limitation (0) and in FV/FM. These 3 parameters were less severely affected by treatment with medium light intensity (1 000 μmol photons m-2s-1 ). The data show that when sun leaves of cotton are exposed for short periods of time to temperatures only slightly suboptimal for photosynthesis, high light intensities can cause marked photoinhibition.Réduction de la photosynthèse chez les feuilles héliophiles de Gossypium hirsutum L sous des conditions de haute intensité de lumière et de température foliaire suboptimale. Des feuilles héliophiles de cotonnier, attachées à la plante (Gossypium hirsutum L var Delta Pine 61) ont été mises dans une cuvette d'échange gazeux et exposées pendant 4 jours à 1 000 ou 1 800 μmol photons m-2 s-1 et à une série de températures d'air (35°, 30°, 25°, 20°C) pendant les périodes d'éclairement de 12 h. La température, pendant les périodes obscures de 12 h, a été maintenue à 25°C. Les plus hauts taux d'assimilation de CO2 (Amax: env 30 μmol CO2 m-2 s-1) ont été atteint à 1 800 μmol photons m -2 s-1 et des températures de l'air de 30° et 35°C. À 30°C et 1 000 μmol photons m-2 s-1 Ama x a diminué de 20%. Aux 2 intensités de lumière, Amax et la conductivité stomatique ont diminué avec la baisse des températures. La réduction en Amax a été très sévère à 1 800 μmol photons m-2 s-1 et 20°C. Les feuilles exposées à ces conditions ont aussi montré des baisses importantes dans les taux d'évolution d'O2 photosynthétique, à saturation en CO2, sous conditions de saturation en lumière (PSmax), de limitation en lumière (Ø) et en FV/FM. Ces 3 paramètres ont été moins sévèrement affectés par le traitement de lumière à moyenne intensité (1 000 μmol photons m-2 s-1). Les données montrent que, lorsque les feuilles héliophiles du cotonnier sont exposées pendant de courtes périodes de temps à des températures seulement légèrement suboptimales pour la photosynthèse, les hautes intensités de lumière peuvent provoquer une photo-inhibition importante