575 research outputs found
Lipid-soluble Vitamins A, D, and E in HIV-Infected Pregnant women in Tanzania.
There is limited published research examining lipid-soluble vitamins in human immunodeficiency virus (HIV)-infected pregnant women, particularly in resource-limited settings. This is an observational analysis of 1078 HIV-infected pregnant women enrolled in a trial of vitamin supplementation in Tanzania. Baseline data on sociodemographic and anthropometric characteristics, clinical signs and symptoms, and laboratory parameters were used to identify correlates of low plasma vitamin A (<0.7 micromol/l), vitamin D (<80 nmol/l) and vitamin E (<9.7 micromol/l) status. Binomial regression was used to estimate risk ratios and 95% confidence intervals. Approximately 35, 39 and 51% of the women had low levels of vitamins A, D and E, respectively. Severe anemia (hemoglobin <85 g/l; P<0.01), plasma vitamin E (P=0.02), selenium (P=0.01) and vitamin D (P=0.02) concentrations were significant correlates of low vitamin A status in multivariate models. Erythrocyte Sedimentation Rate (ESR) was independently related to low vitamin A status in a nonlinear manner (P=0.01). The correlates of low vitamin D status were CD8 cell count (P=0.01), high ESR (ESR >81 mm/h; P<0.01), gestational age at enrollment (nonlinear; P=0.03) and plasma vitamins A (P=0.02) and E (P=0.01). For low vitamin E status, the correlates were money spent on food per household per day (P<0.01), plasma vitamin A concentration (nonlinear; P<0.01) and a gestational age <16 weeks at enrollment (P<0.01). Low concentrations of lipid-soluble vitamins are widely prevalent among HIV-infected women in Tanzania and are correlated with other nutritional insufficiencies. Identifying HIV-infected persons at greater risk of poor nutritional status and infections may help inform design and implementation of appropriate interventions
'Ein Orchester, wie es bisher in Europa noch nicht gesehen und gehört worden war' : das 'Erste Europäische Damenorchester' von Josephine Amann-Weinlich
Die vorliegende Arbeit fügt sich aufs beste in die anspruchsvolle Schriftenreihe des Bremer Sophie Drinker Instituts ein. Sie beschreibt den Werdegang eines Frauenorchesters, des Ersten Europäischen Damenorchesters von Josephine Amann-Weinlich (Wien), 1868 gegründet und bis 1879 mit ausgedehnten Konzertreisen in Europa und Amerika sehr erfolgreich. Die vorliegende Schrift ist die erste vollständige Darstellung dieses bahnbrechenden Unternehmens. Im Blick sind außerdem die Arbeitsbedingungen und die Reaktionen der Kritik: kulturgeschichtlicher Gradmesser par excellence für die ungleichgewichtige und heikle Beziehung der Geschlechter in der Gründerzeit
Titration of mitochondrial fusion rescues Mff-deficient cardiomyopathy
Defects in mitochondrial fusion or fission are associated with many pathologies, raising the hope that pharmacological manipulation of mitochondrial dynamics may have therapeutic benefit. This approach assumes that organ physiology can be restored by rebalancing mitochondrial dynamics, but this concept remains to be validated. We addressed this issue by analyzing mice deficient in Mff, a protein important for mitochondrial fission. Mff mutant mice die at 13 wk as a result of severe dilated cardiomyopathy leading to heart failure. Mutant tissue showed reduced mitochondrial density and respiratory chain activity along with increased mitophagy. Remarkably, concomitant deletion of the mitochondrial fusion gene Mfn1 completely rescued heart dysfunction, life span, and respiratory chain function. Our results show for the first time that retuning the balance of mitochondrial fusion and fission can restore tissue integrity and mitochondrial physiology at the whole-organ level. Examination of liver, testis, and cerebellum suggest, however, that the precise balance point of fusion and fission is cell type specific
Clara Schumann und ihre SchülerInnen am Hoch'schen Konservatorium in Frankfurt a.M.
Clara Schumann ist inzwischen wahrscheinlich die am besten erforschte Musikerin des 19. Jahrhunderts, nicht nur ihrer Verbindung mit Robert Schumann wegen, sondern auch aufgrund des Interesses, das ihr seit den 1970er Jahren von Seiten der Genderforschung entgegengebracht wird. Umso erstaunlicher ist es, dass ihre Lehrtätigkeit am Hoch'schen Konservatorium bisher kaum aufgearbeitet wurde. Annkatrin Babbe hat diese Lücke ausgefüllt und dazu eine große Menge an Material ausgewertet: Briefe, Interviews, Zeitschriften, (Auto-)Biographien von SchülerInnen, Schriften zur Biographie Clara Schumanns und Arbeiten zur Geschichte des Hoch'schen Konservatoriums (einschließlich der Jahresberichte von 1878 bis 1898). Hinzu kam eine Fülle von Presse- und Literaturbelegen über SchülerInnen und Töchter Clara Schumanns. Die meisten von ihnen sind bisher von der Forschung wenig beachtet worden; mit diesem Buch werden sie nun in 53 ausführlichen lexikalischen Artikeln vorgestellt
OPTICAL ANALYSIS OF EFFICIENCY LIMITATIONS OF CU(IN,GA)SE2 GROWN UNDER COPPER EXCESS
Solar cells made from the compound semiconductor Cu(In,Ga)Se2 reach efficiencies of
22:9 % and are thus even better than multi crystalline silicon solar cells. All world records
are achieved using absorber layers with an overall copper deficient composition, but Cu-rich
grown samples have multiple favourable properties. However, especially losses in the open
circuit voltage limit the device performance. Within this work these efficiency limitations
of chalcopyrites grown with copper excess are investigated. The work has been divided
into four chapters addressing different scientific questions.
(i) Do alkali treatments improve Cu-rich absorber layers?
The alkali treatment, which lead to the recent improvements of the efficiency world record,
is adapted to CuInSe2 samples with Cu-rich composition. The treatment leads to an
improvement of the VOC which originates roughly equally from an improvement of the
bulk and the removal of a defect close to the interface. The treatment also improves the
VOC of Cu-poor samples. In both cases, the treatment increases the fill factor (FF) and
leads to a reduction of copper content at the surface.
(ii) Is the VOC limited by deep defects in Cu-rich Cu(In,Ga)Se2?
A deep defect, which likely limits the VOC, is observed in photoluminescence measurements
(PL) independent of a surface treatment. The defect level is proposed to originate from the
second charge transition of the CuIn antisite defect (CuIn(-1/-2)). During the investigation
also a peak at 0:9 eV is detected and attributed to a DA-transition involving a third
acceptor situated (135 ± 10) meV above the valence band. The A3 proposed to originate
from the indium vacancy (VIn). Furthermore the defect was detected in admittance
measurements and in Cu(In,Ga)Se2 samples with low gallium content.
(iii) Is the diode factor intrinsically higher in Cu-rich chalcopyrites?
Cu-rich solar cells exhibit larger diode ideality factors which reduce the FF. A direct link
between the power law exponent from intensity dependent PL measurements of absorbers
and the diode factor of devices is derived and verified using Cu-poor Cu(In,Ga)Se2 samples.
This optical diode factor is the same in Cu-rich and Cu-poor samples.
(iv) Is the quasi Fermi level splitting (qFLs) of Cu-rich Cu(In,Ga)Se2 absorber layers
comparable to Cu-poor samples?
Measuring the qFLs of passivated Cu-rich and Cu-poor Cu(In,Ga)Se2 samples, on average
a 120 meV lower splitting is determined for Cu-rich samples. This difference increases with
gallium content and is likely linked to a defect moving deeper into the bandgap, possibly
related to the second charge transition of the CuIn antisite defect.
Overall, samples with Cu-rich composition are not limited by the diode factor. However,
a deep defect band causes recombination lowering the qFLs and thus the VOC. This defect
is not removed by alkali treatments. A key component to improve Cu-rich solar cells in
the future, especially Cu(In,Ga)Se2, will be to remove or passivate this defect level
Infiltrierende T-Lymphozyten bei Multipler Sklerose: Analyse von Rezeptorrepertoire und Antigenspezifitäten auf dem Niveau einzelner Zellen
ACBD5 and VAPB mediate membrane associations between peroxisomes and the ER
This is the final version of the article. Available from the publisher via the DOI in this record.Peroxisomes (POs) and the endoplasmic reticulum (ER) cooperate in cellular lipid metabolism and form tight structural
associations, which were first observed in ultrastructural studies decades ago. PO–ER associations have been suggested
to impact on a diverse number of physiological processes, including lipid metabolism, phospholipid exchange, metabolite
transport, signaling, and PO biogenesis. Despite their fundamental importance to cell metabolism, the mechanisms
by which regions of the ER become tethered to POs are unknown, in particular in mammalian cells. Here, we identify
the PO membrane protein acyl-coenzyme A–binding domain protein 5 (ACBD5) as a binding partner for the resident
ER protein vesicle-associated membrane protein-associated protein B (VAPB). We show that ACBD5–VAPB interaction
regulates PO–ER associations. Moreover, we demonstrate that loss of PO–ER association perturbs PO membrane expansion
and increases PO movement. Our findings reveal the first molecular mechanism for establishing PO–ER associations
in mammalian cells and report a new function for ACBD5 in PO–ER tethering.This work was supported by grants from the Biotechnology and Biological
Sciences Research Council (BB/K006231/1 and BB/
N01541X/1 to M. Schrader). J. Metz and M. Schrader are supported
by a Wellcome Trust Institutional Strategic Support Award
(WT097835MF and WT105618MA) and L.F. Godinho by a fellowship
from Fundação para a Ciência e a Tecnologia, Portugal (SFRH/
BPD/90084/2012). M. Schrader and A.S. Azadi are supported by
Marie Curie Initial Training Network action PerFuMe (316723).
M. Islinger is supported by MEAMEDMA Anschubförderung, Medical
Faculty Mannheim, University of Heidelberg
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