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The atmospheric lunar tide is one known source of ionospheric variability. The subject received renewed attention as recent studies found a link between stratospheric sudden warmings and amplified lunar tidal perturbations in the equatorial ionosphere. There is increasing evidence from ground observations that the lunar tidal influence on the ionosphere depends on longitude. We use magnetic field measurements from the CHAMP satellite during July 2000 to September 2010 and from the two Swarm satellites during November 2013 to February 2017 to determine, for the first time, the complete seasonal- longitudinal climatology of the semidiurnal lunar tidal variation in the equatorial electrojet intensity. Significant longitudinal variability is found in the amplitude of the lunar tidal variation, while the longitudinal variability in the phase is small. The amplitude peaks in the Peruvian sector (similar to 285 degrees E) during the Northern Hemisphere winter and equinoxes, and in the Brazilian sector (similar to 325 degrees E) during the Northern Hemisphere summer. There are also local amplitude maxima at similar to 55 degrees E and similar to 120 degrees E. The longitudinal variation is partly due to the modulation of ionospheric conductivities by the inhomogeneous geomagnetic field. Another possible cause of the longitudinal variability is neutral wind forcing by nonmigrating lunar tides. A tidal spectrum analysis of the semidiurnal lunar tidal variation in the equatorial electrojet reveals the dominance of the westward propagating mode with zonal wave number 2 (SW2), with secondary contributions by westward propagating modes with zonal wave numbers 3 (SW3) and 4 (SW4). Eastward propagating waves are largely absent from the tidal spectrum. Further study will be required for the relative importance of ionospheric conductivities and nonmigrating lunar tides.
Background/Aims: A recent study revealed that global overexpression of ET-1 causes a slight reduction in systemic blood pressure. Moreover, heterozygous ET-1 knockout mice are hypertensive. The role of ET-1 in human hypertension was so far not addressed by a strict meta-analysis of published human clinical studies.
Methods: We included studies published between January 1, 1990 and February 28, 2017. We included case control studies analyzing untreated essential hypertension or hypertensive patients where antihypertensive medication was discontinued for at least two weeks. Based on the principle of Cochrane systematic reviews, case control studies (CCSs) in PubMed (Medline) and Google Scholar designed to identify the role of endothelin-1 (ET-1) in the pathophysiological of hypertension were screened. Review Manager Version 5.0 (Rev-Man 5.0) was applied for statistical analysis. Mean difference and 95% confidence interval (CI) were shown in inverse variance (IV) fixed-effects model or IV random-effects models.
Results: Eleven studies fulfilling our in-and exclusion criteria were eligible for this meta-analysis. These studies included 450 hypertensive patients and 328 controls. Our meta-analysis revealed that ET-1 plasma concentrations were higher in hypertensive patients as compared to the control patients [mean difference between groups 1.57 pg/mL, 95%Ci [0.47 similar to 2.68, P = 0.005]. These finding were driven by patients having systolic blood pressure higher than 160 mmHg and diastolic blood pressure higher than 100 mmHg.
Conclusions: This meta-analysis showed that hypertensive patients do have elevated plasma ET-1 concentrations. This finding is driven by those patients with high systolic/diastolic blood pressure. Given that the ET-1 gene did not appear in any of the whole genome association studies searching for hypertension associated gene loci, it is very likely that the elevated plasma ET-1 concentrations in hypertensive patients are secondary to hypertension and may reflect endothelial cell damage.
The Role of Super-Atom Molecular Orbitals in Doped Fullerenes in a Femtosecond Intense Laser Field
(2017)
The interaction of gas phase endohedral fullerene Ho3N@C-80 with intense (0.1-5 x 10(14) W/cm(2)), short (30 fs), 800 nm laser pulses was investigated. The power law dependence of Ho3N@C-80(q+), q = 1-2, was found to be different from that of C-60. Time-dependent density functional theory computations revealed different light-induced ionization mechanisms. Unlike in C-60, in doped fullerenes, the breaking of the cage spherical symmetry makes super atomic molecular orbital (SAMO) states optically active. Theoretical calculations suggest that the fast ionization of the SAMO states in Ho3N@C-80 is responsible for the n = 3 power law for singly charged parent molecules at intensities lower than 1.2 x 10(14) W/cm(2).
It is widely accepted that modern pigs were domesticated independently at least twice, and Chinese native pigs are deemed as direct descendants of the first domesticated pigs in the corresponding domestication centers. By analyzing mitochondrial DNA sequences of an extensive sample set spanning 10,000 years, we find that the earliest pigs from the middle Yellow River region already carried the maternal lineages that are dominant in both younger archaeological populations and modern Chinese pigs. Our data set also supports early Neolithic pig utilization and a long-term in situ origin for northeastern Chinese pigs during 8,000-3,500 BP, suggesting a possibly independent domestication in northeast China. Additionally, we observe a genetic replacement in ancient northeast Chinese pigs since 3,500 BP. The results not only provide increasing evidence for pig origin in the middle Yellow River region but also depict an outline for the process of early pig domestication in northeast China.
5-Jahres-Verlauf der LRS
(2017)
Fragestellung: Untersucht wird der Verlauf von Kindern mit Lese-Rechtschreibstörungen (LRS) über gut 5 Jahre unter Berücksichtigung des Einflusses des Geschlechts der Betroffenen. Außerdem werden Auswirkungen der LRS auf das spätere Schriftsprachniveau und den Schulerfolg überprüft. Methodik: Eingangs wurden 995 Schüler zwischen 6 und 16 Jahren untersucht. Ein Teil dieser Kinder ist nach 43 sowie 63 Monaten nachuntersucht worden. Eine LRS wurde diagnostiziert, wenn für das Lesen bzw. Rechtschreiben das doppelte Diskrepanzkriterium von 1.5 Standardabweichungen zur nonverbalen Intelligenz und dem Mittelwert der Klassenstufe erfüllt war und gleichzeitig keine Minderbegabung vorlag. Ergebnisse: Die LRS weist über einen Zeitraum von 63 Monaten eine hohe Störungspersistenz von knapp 70 % auf. Der 5-Jahres-Verlauf der mittleren Lese- und Rechtschreibleistungen wurde nicht vom Geschlecht beeinflusst. Trotz durchschnittlicher Intelligenz blieben die LRS-Schüler in der Schriftsprache mindestens eine Standardabweichung hinter durchschnittlich und etwa 0.5 Standardabweichungseinheiten hinter unterdurchschnittlich intelligenten Kindern zurück. Der Schulerfolg der LRS-Schüler glich dem unterdurchschnittlich intelligenter Kinder und fiel deutlich schlechter aus als bei durchschnittlich intelligenten Kontrollkindern. Schlussfolgerungen: Eine LRS stellt ein erhebliches Entwicklungsrisiko dar, was frühzeitige Diagnostik- und Therapiemaßnahmen erfordert. Dafür sind reliable und im Hinblick auf die resultierenden Prävalenzraten sinnvolle, allgemein anerkannte Diagnosekriterien essenziell.
Zum Hundertsten nichts Neues
(2017)
Shifts among Eukaryota, Bacteria, and Archaea define the vertical organization of a lake sediment
(2017)
Background: Lake sediments harbor diverse microbial communities that cycle carbon and nutrients while being constantly colonized and potentially buried by organic matter sinking from the water column. The interaction of activity and burial remained largely unexplored in aquatic sediments. We aimed to relate taxonomic composition to sediment biogeochemical parameters, test whether community turnover with depth resulted from taxonomic replacement or from richness effects, and to provide a basic model for the vertical community structure in sediments. Methods: We analyzed four replicate sediment cores taken from 30-m depth in oligo-mesotrophic Lake Stechlin in northern Germany. Each 30-cm core spanned ca. 170 years of sediment accumulation according to Cs-137 dating and was sectioned into layers 1-4 cm thick. We examined a full suite of biogeochemical parameters and used DNA metabarcoding to examine community composition of microbial Archaea, Bacteria, and Eukaryota. Results: Community beta-diversity indicated nearly complete turnover within the uppermost 30 cm. We observed a pronounced shift from Eukaryota- and Bacteria-dominated upper layers (<5 cm) to Bacteria-dominated intermediate layers (5-14 cm) and to deep layers (>14 cm) dominated by enigmatic Archaea that typically occur in deep-sea sediments. Taxonomic replacement was the prevalent mechanism in structuring the community composition and was linked to parameters indicative of microbial activity (e.g., CO2 and CH4 concentration, bacterial protein production). Richness loss played a lesser role but was linked to conservative parameters (e.g., C, N, P) indicative of past conditions. Conclusions: By including all three domains, we were able to directly link the exponential decay of eukaryotes with the active sediment microbial community. The dominance of Archaea in deeper layers confirms earlier findings from marine systems and establishes freshwater sediments as a potential low-energy environment, similar to deep sea sediments. We propose a general model of sediment structure and function based on microbial characteristics and burial processes. An upper "replacement horizon" is dominated by rapid taxonomic turnover with depth, high microbial activity, and biotic interactions. A lower "depauperate horizon" is characterized by low taxonomic richness, more stable "low-energy" conditions, and a dominance of enigmatic Archaea.
Most studies of aquatic plankton focus on either macroscopic or microbial communities, and on either eukaryotes or prokaryotes. This separation is primarily for methodological reasons, but can overlook potential interactions among groups. Here we tested whether DNA metabarcoding of unfractionated water samples with universal primers could be used to qualitatively and quantitatively study the temporal dynamics of the total plankton community in a shallow temperate lake. Significant changes in the relative proportions of normalized sequence reads of eukaryotic and prokaryotic plankton communities over a 3-month period in spring were found. Patterns followed the same trend as plankton estimates measured using traditional microscopic methods. The bloom of a conditionally rare bacterial taxon belonging to Arcicella was characterized, which rapidly came to dominate the whole lake ecosystem and would have remained unnoticed without metabarcoding. The data demonstrate the potential of universal DNA metabarcoding applied to unfractionated samples for providing a more holistic view of plankton communities.
Teachers' use of evaluation data to improve instruction and its relationship to student achievement
(2017)
In Deutschland stehen Lehrkräften mit Ergebnissen aus Vergleichsarbeiten, zentralen Abschlussprüfungen und internen Evaluationen verschiedene Informationen zur Verfügung. Diese Daten können von ihnen dazu verwendet werden, den eigenen Unterricht zu reflektieren und weiterzuentwickeln. Die Studie geht auf Basis des IQB-Ländervergleichs 2012 den Fragen nach, ob und welche Daten von Lehrkräften zur Unterrichtsentwicklung herangezogen werden und ob datenbasierte Unterrichtsentwicklung mit Schülerleistung zusammenhängt. Die Betrachtung mehrerer Evaluationsverfahren ermöglicht eine kontrastierende Analyse und die Untersuchung einer gemeinsamen Verwendung mehrerer Informationsquellen. Die überwiegende Mehrheit der befragten Lehrkräfte berichtet, Evaluationsergebnisse als Ausgangspunkt zur Unterrichtsentwicklung zu verwenden. Allerdings zeigt sich Heterogenität zwischen einzelnen Unterrichtsentwicklungsaktivitäten und Lehrkräften. Zur Initiierung einzelner Entwicklungsaktivitäten werden auch mehrere Datenquellen simultan herangezogen. Ein direkter signifikanter Zusammenhang zwischen datenbasierter Unterrichtsentwicklung und Schülerleistung kann nicht festgestellt werden. (DIPF/Orig.).