107 research outputs found

    Design of Pre-Dumping Ring Spin Rotator with a Possibility of Helicity Switching for Polarized Positrons at the ILC

    Full text link
    The use of polarized beams enhance the possibility of the precision measurements at the International Linear Collider (ILC). In order to preserve the degree of polarization during beam transport spin rotators are included in the current TDR ILC Lattice. In this report some advantages of using a combined spin rotator/spin flipper are discussed. A few possible lattice designs of spin flipper developed at DESY in 2012 are presented.Comment: Talk presented at the International Workshop on Future Linear Colliders (LCWS15), Whistler, Canada, 2-6 November 201

    Memory deficits in APP23/Abca1+/− mice correlate with the level of Aβ oligomers

    Get PDF
    ABCA1, a member of the ATP-binding cassette family of transporters, lipidates ApoE (apolipoprotein A) and is essential for the generation of HDL (high-density lipoprotein)-like particles in the CNS (central nervous system). Lack of Abca1 increases amyloid deposition in several AD (Alzheimer's disease) mouse models. We hypothesized that deletion of only one copy of Abca1 in APP23 (where APP is amyloid precursor protein) AD model mice will aggravate memory deficits in these mice. Using the Morris Water Maze, we demonstrate that 2-year-old Abca1 heterozygous APP23 mice (referred to as APP23/het) have impaired learning during acquisition, and impaired memory retention during the probe trial when compared with age-matched wild-type mice (referred to as APP23/wt). As in our previous studies, the levels of ApoE in APP23/het mice were decreased, but the differences in the levels of Aβ and thioflavin-S-positive plaques between both groups were insignificant. Importantly, dot blot analysis demonstrated that APP23/het mice have a significantly higher level of soluble A11-positive Aβ (amyloid β protein) oligomers compared with APP23/wt which correlated negatively with cognitive performance. To confirm this finding, we performed immunohistochemistry with the A11 antibody, which revealed a significant increase of A11-positive oligomer structures in the CA1 region of hippocampi of APP23/het. This characteristic region-specific pattern of A11 staining was age-dependent and was missing in younger APP23 mice lacking Abca1. In contrast, the levels of Aβ*56, as well as other low-molecular-mass Aβ oligomers, were unchanged among the groups. Overall, the results of the present study demonstrate that in aged APP23 mice memory deficits depend on Abca1 and are likely to be mediated by the amount of Aβ oligomers deposited in the hippocampus

    Ultrafast electronic processes in an insulator The Be and O sites in BeO

    Get PDF
    The short time dynamics of amorphous beryllium oxide a BeO has been investigated for electronic excitation ionization by fast incident electrons, as well as by Ar7 , Ar15 , Xe15 , and Xe31 ions at velocities of 6 10 the speed of light. Site specific Auger electron spectra induced by fast heavy ions are the central point of this investigation. Electron induced Auger spectra serve as a reference and electron energy loss EELS spectroscopy as well as resonant inelastic X ray scattering RIXS are invoked for quantitative understanding. For the heavy ion case, we observe strong variations in the corresponding spectral distributions of Be K and O K Auger lines. These are related to local changes of the electron density, of the electron temperature and even of the electronic band structure of BeO on a femtosecond time scale after the passage of highly charged heavy ions

    Hair Cortisol as a Marker of Intergenerational Heritage of War? A Study of Veterans and Their Offspring

    Get PDF
    Objective Posttraumatic stress disorder (PTSD) has been associated with lower circulating cortisol levels in specific subgroups, which have also been found in the offspring of people with PTSD. The analysis of hair cortisol concentrations (HCC) is a recent methodology which is used to assess long-term systemic cortisol levels. We aimed to study veterans with war-related lifetime PTSD and their respective offspring with regards to HCC. We also studied the influence of lifetime major depressive disorder (MDD), war experiences, and childhood adversities on HCC in these groups. Methods 31 male veterans with PTSD and 28 without PTSD and 69 adult offspring were studied. HCC were quantified by liquid chromatography tandem-mass spectrometry. Results No differences in HCC were found between veterans with and without PTSD, or between their respective offspring. Veterans without MDD showed a positive association between total war exposure and HCC. Veterans reporting more frequent childhood physical abuse had lower HCC. Veterans-with-PTSD’s offspring with MDD had increased HCC compared to offspring without MDD. Offspring’s exposure to more frequent childhood physical abuse was negatively associated with HCC in those without MDD. Conclusion HCC did not appear to constitute a marker of intergenerational heritage of war-related PTSD, except in the case of veteranswith-PTSD’s offspring with MDD. Our data suggest that HCC is a marker of adult reported childhood physical abus

    Impairment of Adolescent Hippocampal Plasticity in a Mouse Model for Alzheimer's Disease Precedes Disease Phenotype

    Get PDF
    The amyloid precursor protein (APP) was assumed to be an important neuron-morphoregulatory protein and plays a central role in Alzheimer's disease (AD) pathology. In the study presented here, we analyzed the APP-transgenic mouse model APP23 using 2-dimensional gel electrophoresis technology in combination with DIGE and mass spectrometry. We investigated cortex and hippocampus of transgenic and wildtype mice at 1, 2, 7 and 15 months of age. Furthermore, cortices of 16 days old embryos were analyzed. When comparing the protein patterns of APP23 with wildtype mice, we detected a relatively large number of altered protein spots at all age stages and brain regions examined which largely preceded the occurrence of amyloid plaques. Interestingly, in hippocampus of adolescent, two-month old mice, a considerable peak in the number of protein changes was observed. Moreover, when protein patterns were compared longitudinally between age stages, we found that a large number of proteins were altered in wildtype mice. Those alterations were largely absent in hippocampus of APP23 mice at two months of age although not in other stages compared. Apparently, the large difference in the hippocampal protein patterns between two-month old APP23 and wildtype mice was caused by the absence of distinct developmental changes in the hippocampal proteome of APP23 mice. In summary, the absence of developmental proteome alterations as well as a down-regulation of proteins related to plasticity suggest the disturption of a normally occurring peak of hippocampal plasticity during adolescence in APP23 mice. Our findings are in line with the observation that AD is preceded by a clinically silent period of several years to decades. We also demonstrate that it is of utmost importance to analyze different brain regions and different age stages to obtain information about disease-causing mechanisms

    Bright light therapy in pregnant women with major depressive disorder: Study protocol for a randomized, double-blind, controlled clinical trial

    Get PDF
    Background: Depression during pregnancy is a common and high impact disease. Generally, 5-10 % of pregnant women suffer from depression. Children who have been exposed to maternal depression during pregnancy have a higher risk of adverse birth outcomes and more often show cognitive, emotional and behavioural problems. Therefore, early detection and treatment of antepartum depression is necessary. Both psychotherapy and antidepressant medication, first choice treatments in a non-pregnant population, have limitations in treating depression during pregnancy. Therefore, it is urgent and relevant to investigate alternative treatments for antepartum depression. Bright light therapy (BLT) is a promising treatment for pregnant women with depressive disorder, for it combines direct availability, sufficient efficacy, low costs and high safety, taking the safety for the unborn child into account as well. Methods: In this study, 150 pregnant women (12-18 weeks pregnant) with a DSM-V diagnosis of depressive disorder will be randomly allocated in a 1:1 ratio to one of the two treatment arms: treatment with BLT (9.000 lux) or treatment with dim red light therapy (100 lux). Both groups will be treated for 6 weeks at home on a daily basis for 30 min, within 30 min of habitual wake-up time. Follow-up will take place after 6 weeks of therapy, 3 and 10 weeks after end of therapy, at birth and 2, 6 and 18 months postpartum. Primary outcome will be the average change in depressive symptoms between the two groups, as measured by the Structured Interview Guide for the Hamilton Depression Scale - Seasonal Affective Disorder version and the Edinburg Postnatal Depression Scale. Changes in rating scale scores of these questionnaires over time will be analysed using generalized linear mixed models. Secondary outcomes will be the changes in maternal cortisol and melatonin levels, in maternal sleep quality and gestational age, birth weight, infant behaviour, infant cortisol exposure and infant cortisol stress response. Discussion: If BLT reduces depressive symptoms in pregnant women, it will provide a safe, cheap, non-pharmacological and efficacious alternative treatment for psychotherapy and antidepressant medication in treating antepartum depression, without any expected adverse reactions for the unborn child. Trial registration: Netherlands Trial Register NTR5476. Registered 5 November 2015

    Anwendung des "Inverted Classroom Model" im Lehrmodul "Neue Klassifikation von parodontalen und periimplantären Erkrankungen und Zuständen" während der COVID-19-Pandemie

    No full text
    Background: Due to the need for patient-free dental education during the COVID-19 pandemic, Hannover Medical School (MHH) implemented a new periodontology module. Its didactic structure was based on the "inverted classroom model" (ICM) in combination with elements of case-based learning. The educational objective was to increase the diagnostic confidence of dental students in the classification of periodontal patients (staging & grading), based on 33 digitized patient cases. To assess the suitability of the module for future dental curricula, this study aimed to evaluate student satisfaction and skills acquisition. Methods: The periodontology module, which was attended by final year dental students of MHH (n=55, mean age: 26.5±3.9 years, male/female ratio: 24.1%/75.9%) was evaluated in a two-tiered way. Student satisfaction was recorded using a questionnaire. Learning success was assessed by comparing error rates in patient case classifications before (T0) and after (T1) participation in the periodontology module.Results: The study found a high level of student satisfaction with the ICM format and a significant reduction in error rates (T0 error rate=28.3%; MV±SD=3.12±1.67 vs. T1 error rate=18.7%; MV±SD=2.06±1.81; Delta=9.6%). However, of the 11 diagnostic decisions required, only four parameters (extent, grading, percentage of bone loss per age, phenotype) showed significant improvements, with effect sizes ranging from small to medium.Conclusions: The ICM-based teaching concept is definitely not an alternative to patient-based learning. However, in regard to student satisfaction and learning success, it might be superior to conventional classroom-based lectures, especially when complex topics are covered. In summary, the newly developed periodontology module may be a useful addition to traditional dental education in future curricula, even for the time after the COVID-19 pandemic.Hintergrund: Im Zuge der Patienten-freien Lehre zur Zeit der COVID-19-Pandemie wurde ein auf dem "Inverted Classroom Model" (ICM) basierendes Parodontologie-Modul in die zahnmedizinische Lehre eingeführt. Anhand von 33 digital ausgearbeiteten Patientenfällen sollte die diagnostische Sicherheit von angehenden Zahnärztinnen und Zahnärzten bei der Klassifizierung parodontal erkrankter Patienten (Staging & Grading) gesteigert werden. Um die Eignung des Moduls auch hinsichtlich der Entwicklung zukünftiger, zahnmedizinischer Curricula überprüfen zu können, war es das Ziel dieser Studie, die Zufriedenheit und den Kompetenzerwerb der Studierenden zu ermitteln.Methodik: Die Evaluation des Parodontologie-Moduls, das von Zahnmedizinstudierenden der Medizinischen Hochschule Hannover aus dem 10. Semester (n=55, mittleres Alter: 26,5±3,9 Jahre, Verhältnis männlich/ weiblich: 23,6%/76,4%) besucht wurde, erfolgte zweigeteilt. So wurde die studentische Zufriedenheit Fragebogen-basiert erfasst. Der Lernerfolg wurde durch den statistischen Vergleich der Fehlerquote bei der Klassifizierung eines Patientenfalls vor (T0) und nach (T1) Teilnahme am Parodontologie-Modul ermittelt.Ergebnisse: Es konnte eine hohe Zufriedenheit der Studierenden mit dem ICM-Format sowie eine signifikante Reduktion der Fehlerquote (T0 Fehlerquote=28,3%; MW±SA=3,12±1,67 vs. T1 Fehlerquote=18,7%; MW±SA=2,06±1,81; Delta=9,6%) festgestellt werden. Von den insgesamt 11 diagnostischen Entscheidungen zeigten aber nur vier Parameter (Ausdehnung, Grading, prozentualer Knochenabbau pro Alter, Phänotyp) eine signifikante Verbesserung mit schwach- bis mittelgradiger Effektstärke.Schlussfolgerung: Das ICM-basierte Lehrkonzept stellt sicherlich keine Alternative zur Patienten-basierten Lehre dar, könnte aber hinsichtlich der Lehrzufriedenheit und des Lernerfolgs insbesondere bei komplexen Themengebieten der klassischen Präsenz-basierten Vorlesung überlegen sein. Das neu entwickelte Parodontologie-Modul stellt auch für die Zeit nach der COVID-19-Pandemie eine sinnvolle Ergänzung in der zahnmedizinischen Lehre dar
    • …
    corecore