Imaging spin-filter efficiency of W(001) and Ir(001) single crystals

Während der letzten Jahre wurde für Spinfilter-Detektoren ein wesentlicher Schritt in Richtung stark erhöhter Effizienz vollzogen. Das ist eine wichtige Voraussetzung für spinaufgelöste Messungen mit Hilfe von modernen Elektronensp ektrometern und Impulsmikroskopen. In dieser Doktorarbeit wurden bisherige Arbeiten der parallel abbildenden Technik weiterentwickelt, die darauf beruht, dass ein elektronenoptisches Bild unter Ausnutzung der k-parallel Erhaltung in der Niedrigenergie-Elektronenbeugung auch nach einer Reflektion an einer kristallinen Oberfläche erhalten bleibt. Frühere Messungen basierend auf der spekularen Reflexion an einerrnW(001) Oberfläche [Kolbe et al., 2011; Tusche et al., 2011] wurden auf einenrnviel größeren Parameterbereich erweitert und mit Ir(001) wurde ein neues System untersucht, welches eine sehr viel längere Lebensdauer der gereinigten Kristalloberfläche im UHV aufweist. Die Streuenergie- und Einfallswinkel-“Landschaft” der Spinempfindlichkeit S und der Reflektivität I/I0 von gestreuten Elektronen wurde im Bereich von 13.7 - 36.7 eV Streuenergie und 30◦ - 60◦ Streuwinkel gemessen. Die dazu neu aufgebaute Messanordnung umfasst eine spinpolarisierte GaAs Elektronenquellernund einen drehbaren Elektronendetektor (Delayline Detektor) zur ortsauflösenden Detektion der gestreuten Elektronen. Die Ergebnisse zeigen mehrere Regionen mit hoher Asymmetrie und großem Gütefaktor (figure of merit FoM), definiert als S2 · I/I0. Diese Regionen eröffnen einen Weg für eine deutliche Verbesserung der Vielkanal-Spinfiltertechnik für die Elektronenspektroskopie und Impulsmikroskopie. Im praktischen Einsatz erwies sich die Ir(001)-Einkristalloberfläche in Bezug auf längere Lebensdauer im UHV (ca. 1 Messtag), verbunden mit hoher FOM als sehr vielversprechend. Der Ir(001)-Detektor wurde in Verbindung mit einem Halbkugelanalysator bei einem zeitaufgelösten Experiment im Femtosekunden-Bereich am Freie-Elektronen-Laser FLASH bei DESY eingesetzt. Als gute Arbeitspunkte erwiesen sich 45◦ Streuwinkel und 39 eV Streuenergie, mit einer nutzbaren Energiebreite von 5 eV, sowie 10 eV Streuenergie mit einem schmaleren Profil von < 1 eV aber etwa 10× größerer Gütefunktion. Die Spinasymmetrie erreicht Werte bis 70 %, was den Einfluss von apparativen Asymmetrien deutlich reduziert. Die resultierende Messungen und Energie-Winkel-Landschaft zeigt recht gute Übereinstimmung mit der Theorie (relativistic layer-KKR SPLEED code [Braun et al., 2013; Feder et al.,rn2012])

Polyunsaturated fatty acid-enriched diets used for the treatment of canine chronic enteropathies decrease the abundance of selected genes of cholesterol homeostasis

Lipids are important for cell function and survival, but abnormal concentrations may lead to various diseases. Cholesterol homeostasis is greatly dependent on the active transport by membrane proteins, whose activities coordinate lipid status with cellular function. Intestinal Niemann-Pick C1-Like 1 protein (NPC1L1) and scavenger receptor B1 (SR-B1) participate in the uptake of extracellular cholesterol, whereas ATP binding cassette A1 (ABCA1) mediates the efflux of excessive intracellular cholesterol. Caveolin-1 binds cholesterol and fatty acids (FA) and participates in cholesterol trafficking. Sterol response element binding protein-2 (SREBP-2) is a sensor that regulates intracellular cholesterol synthesis. Given that cholesterol is a constituent of chylomicrons, whose synthesis is enhanced with an increased FA supply, we tested the hypothesis that feeding polyunsaturated FA (PUFA)-enriched diets in treatment of canine chronic enteropathies alters the mRNA expression of genes involved in cholesterol homeostasis. Using quantitative reverse transcriptase polymerase chain reaction (RT-PCR), we compared the mRNA abundance of NPC1L1, SR-B1, ABCA1, caveolin-1, and SREBP-2 in duodenal mucosal biopsies of dogs with food-responsive diarrhea (FRD; n=14) and inflammatory bowel disease (IBD; n=7) before and after treatment with cholesterol-free PUFA-enriched diets and in healthy controls (n=14). The abundance of caveolin-1, ABCA1, and SREBP-2 were altered by PUFA-enriched diets (P<0.05), whereas that of NPC1L1 and SR-B1 mRNA remained unchanged. The gene expression of caveolin-1, ABCA1, and SREBP-2 was down-regulated (P<0.05) by PUFA-enriched diets in IBD dogs only. Our results suggest that feeding PUFA-enriched diets may alter cholesterol homeostasis in duodenal mucosal cells of dogs suffering from IBD.

La valeur de la femme dans la société traditionnelle Bətí-faŋ

Le Bətí-faŋ est une langue parlée dans la sous-région Afrique centrale, notamment au Cameroun, en Guinée Équatorial, au Gabon et à Sao Tomé et Principe. Le Bətí-faŋ est un peuple fier, avec un passé culturel à la fois important et mystérieux. Certains de ses aspects culturels aujourd'hui sont perdus, dû, en grande partie, à l'action de la religion occidentale et de la colonisation. De nombreuses pratiques alors usitées se voient interdites, à cause des idées préconçues et des interprétations subjectives qui sont accordées à ses pratiques. De même, la valeur et la place que l'Homme Bətí accorde à la femme dans la société s’en trouve pervertie, ceci pour servir les desseins de l’oppresseur. Cet aspect en particulier de la société traditionnelle Bətí-faŋ a souvent porté à polémique. Ces préjugés et interprétations, sont pour la plupart, fréquemment avancées sans que la philosophie de cette société, le contexte, l'époque, et le symbolisme des dits effets ou individus ne soient pris en compte. Cet article va s’arrêter sur la femme Bətí en particulier. Nous essaierons de faire ressortir le symbolisme qui entoure celle-ci. Nous insisterons sur la valeur, ainsi que sur la place et l'importance accordées à celle-ci dans la société traditionnelle des seigneurs de la forêt. Pour se faire, nous porterons notre attention sur les formes de mariages qui ont marquées cette époque. Nous nous étendrons aussi sur l’importance accordée au nombre, ainsi que son impact sur la vie culturelle de l'« Atí ». Nous brosserons enfin, un petit aperçu des rites spécifiques aux femmes qui dénotent de leur impact sur le quotidien des seigneurs de la forêt.

Cellular telephone use and time trends in brain tumour mortality in Switzerland from 1969 to 2002

A rising concern exists that with the widespread use of mobile communication technologies, the incidence of brain tumours may increase. On the basis of data from the Swiss national mortality registry from 1969 to 2002, annual age-standardized brain tumour mortality rates per 100,000 person-years were calculated using the European standard population. Time trend analyses were performed by the Poisson regression for six different age groups in men and women separately. The study period was divided into two intervals: before and after 1987, when the analogue mobile technology was introduced in Switzerland. Age-standardized brain tumour mortality rates ranged between 3.7 and 6.7 for men and 2.5 and 4.4 for women per 100,000 person-years. For the whole study period, a significant increase in brain tumour mortality was observed for men and women in the older age groups (60-74 and 75+ years) but not in the younger ones in whom mobile phone use was more prevalent. Time trend analyses restricted to data from 1987 onwards revealed relatively stable brain tumour mortality rates in all age groups. For instance, the annual change in brain tumour mortality rate for the 45-59-year age group was -0.3% (95% confidence interval: -1.7; 1.1) for men and -0.4% (95% confidence interval:-2.2; 1.3) for women. We conclude that after the introduction of mobile phone technology in Switzerland, brain tumour mortality rates remained stable in all age groups. Our results suggest that mobile phone use is not a strong risk factor in the short term for mortality from brain tumours. Ecological analyses like this, however, are limited in their ability to reveal potentially small increases in risk for diseases with a long latency period.

The Copper Strike of 1968-1969

In May of 1968, workers at the Kingston mine, a branch of the Calumet Division of Universal Oil Products walked off the site in protest of a safety issue involving a man-car. Knowing their contracts were due for negotiation in just a few months, the workers quickly returned, only to find themselves striking yet again just three months later, when negotiations failed. Requesting pay equal to that of the workers at the nearby White Pine mine was unacceptable to the heads of Universal Oil, the corporation which bought the long running Calumet & Hecla just a year earlier in 1968. The strike would last for nine months, ending in a total shutdown of all mining operations on the Keweenaw Peninsula, and bring an economic hardship to the area that would take decades to recover from. The Copper Strike of 1968-1969 is often forgotten, though extremely important to the story of the copper industry in Michigan, as well as to the United States. This paper has not yet been submitted.

The Bison: 1969

This digital object was funded in part through a grant from the Andrew W. Mellon Foundation. The digitalization of this object was part of a collaborative effort with the Washington Research Library Consortium and George Washington University.

Clinical benefit and quality of life in patients with advanced pancreatic cancer receiving gemcitabine plus capecitabine versus gemcitabine alone: a randomized multicenter phase III clinical trial--SAKK 44/00-CECOG/PAN.1.3.001

To compare clinical benefit response (CBR) and quality of life (QOL) in patients receiving gemcitabine (Gem) plus capecitabine (Cap) versus single-agent Gem for advanced/metastatic pancreatic cancer.

The ARCH Projects: design and rationale (IAASSG 001).

OBJECTIVE A number of factors limit the effectiveness of current aortic arch studies in assessing optimal neuroprotection strategies, including insufficient patient numbers, heterogenous definitions of clinical variables, multiple technical strategies, inadequate reporting of surgical outcomes and a lack of collaborative effort. We have formed an international coalition of centres to provide more robust investigations into this topic. METHODS High-volume aortic arch centres were identified from the literature and contacted for recruitment. A Research Steering Committee of expert arch surgeons was convened to oversee the direction of the research. RESULTS The International Aortic Arch Surgery Study Group has been formed by 41 arch surgeons from 10 countries to better evaluate patient outcomes after aortic arch surgery. Several projects, including the establishment of a multi-institutional retrospective database, randomized controlled trials and a prospectively collected database, are currently underway. CONCLUSIONS Such a collaborative effort will herald a turning point in the surgical management of aortic arch pathologies and will provide better powered analyses to assess the impact of varying surgical techniques on mortality and morbidity, identify predictors for neurological and operative risk, formulate and validate risk predictor models and review long-term survival outcomes and quality-of-life after arch surgery.

Ḥinnûk qāṭān : undzi seifer muser šraibn dś jdr faṭr un muṭr zain meḥuyev ria leine kindr tzu gwinn loišn koideš ...

Digitalisat der Ausg. [S.l.], [ca. 1750]

Sēfer Ḥinnûk qāṭān : wailn unzra ṭeri muser šraibn dz jedr faṭr un muhṭr šuldig zain ire kindr tzu lernn loišn ha-koideš um unzri heiligi toire tzu di Jiśroel iz warn miṭgigebn ...

Digitalisat der Ausg. Amśṭrdm, 1766/67