654 research outputs found
Palaeolimnology of Lake Sapanca and identification of historic earthquake signals, Northern Anatolian Fault Zone (Turkey)
Lake Sapanca is located on a strand of the Northern Anatolian Fault Zone (NAFZ, Turkey), where a series of strong earthquakes (Ms >6.0) have occurred over the past hundred years. Identifying prehistoric
earthquakes in and around Lake Sapanca is key to a better understanding of plate movements along the
NAFZ. This study contributes to the development of palaeolimnological tools to identify past earthquakes
in Lake Sapanca. To this end several promising proxies were investigated, specifically lithology, magnetic
susceptibility, grain size (thin-section and laser analysis), geochemistry, pollen concentration, diatom
assemblages, 137Cs and 210Pb. Sedimentological indicators provided evidence for reworked, turbidite-like
or homogeneous facies (event layers) in several short cores (<45 cm). Other indicators of sediment input
and the historical chronicles available for the area suggest that three of these event layers likely originated
from the AD 1957, 1967 and 1999 earthquakes. Recent changes in sediment deposition and nutrient
levels have also been identified, but are probably not related to earthquakes. This study demonstrates
that a combination of indicators can be used to recognize earthquake-related event layers in cores that encompass a longer period of time
Die Testung von Äpfeln auf ihre Allergenität
Apples have several allergens which, when eaten, lead to symptoms in the mouth within 5-10 min-and therefore cannot be eaten by those suffering from apple allergies. In Germany around 7.5 million people have developed specific antibodies against the main allergen (Mal d 1) in apples and are thus sensitized. At least 3.5 million of them develop the sometimes-considerable allergic symptoms as an expression of an Oral Allergy Syndrome. So far there is no drug therapy for this allergy. Apple allergy sufferers can therefore only do without apples entirely, or eat apples that have been heated beforehand or look for varieties that contain few allergens and can therefore be described as "allergy-friendly" apple varieties. Solely determinations of allergens in the laboratory cannot predict whether an apple can be eaten by apple allergy sufferers without allergic symptoms; clinical trials are required for this. We describe a standardized clinical, oral provocation test that can be used to characterize a low-allergen, allergy-friendly apple or apple variety. The results of such at least three-year tests can be used to award the ECARF seal for allergy-friendly products
Conditional reciprocal stressor-strain effects in university students : a cross-lagged panel study in Germany
University students worldwide are facing increasing mental health challenges. Traditional stress models, like the Job/Study Demand-Resources Model, link stressors directly to strain. Yet, recent studies suggest the influence of strain on stressors may be even stronger. Our research explored these reciprocal dynamics among university students, considering social support and mindfulness as potential moderators. We conducted a two-wave panel study with 264 university students. We ran separate cross-lagged panel structural equation analyses for three key health outcomes—emotional exhaustion, depression, and well-being—each paired with perceived study stressors, specifically workload and work complexity. Findings revealed significant stressor and strain effects, with social support notably moderating the impact of emotional exhaustion on workload. These insights challenge traditional stress theories and underscore the importance of mental health support and effective stress management strategies for students, emphasizing the need for proactive mental health initiatives in academic environments
Precursors of Cytochrome Oxidase in Cytochrome-Oxidase-Deficient Cells of Neurospora crassa
Three different cell types of Neurospora crassa deficient in cytochrome oxidase were studied: the nuclear mutant cni-1, the cytoplasmic mutant mi-1 and copper-depleted wild-type cells.
* 1.
The enzyme-deficient cells have retained a functioning mitochondrial protein synthesis. It accounted for 12–16% of the total protein synthesis of the cell. However, the analysis of mitochondrial translation products by gel electrophoresis revealed that different amounts of individual membrane proteins were synthesized. Especially mutant cni-1 produced large amounts of a small molecular weight translation product, which is barely detectable in wild-type.
* 2.
Mitochondrial preparations of cytochrome-oxidase-deficient cells were examined for precursors of cytochrome oxidase. The presence of polypeptide components of cytochrome oxidase in the mitochondria was established with specific antibodies. On the other hand, no significant amounts of heme a could be extracted.
* 3.
Radioactively labelled components of cytochrome oxidase were isolated by immunoprecipitation and analysed by gel electrophoresis. All three cell types contained the enzyme components 4–7, which are translated on cytoplasmic ribosomes. The mitochondrially synthesized components 1–3 were present in mi-1 mutant and in copper-depleted wild-type cells. In contrast, components 2 and 3 were not detectable in the nuclear mutant cni-1. Both relative and absolute amounts of these polypeptides in the enzyme-deficient cells were quite different from those in wild-type cells.
* 4.
The components of cytochrome oxidase found in the enzyme-deficient cells were tightly associated with the mitochondrial membranes.
* 5.
Processes, which affect and may control the production of enzyme precursors or their assembly to a functional cytochrome oxidase are discussed
Подготовка к аккредитации органа по сертификации продукции и услуг
Работа посвящена обзору процедуры аккредитации сертификационных органов. Проведенное исследование позволяет утверждать, что рассмотренная процедура строго регламентирована законодательными нормами и правилами. Правом проведения аккредитации в национальной системе сертификации обладает только Федеральная служба по аккредитации, в различных добровольных системах сертификации данную процедуру может проводить организация, создавшая определенную добровольную систему.The work is devoted to the review of the procedure for accreditation of certification bodies. The carried out research allows to assert that the considered procedure is strictly regulated by legislative norms and rules. The accreditation authority in the national certification system has only the Federal Service for Accreditation, in various voluntary certification systems this procedure can be carried out by the organization that created a certain voluntary system
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A Practical Guide to the Automated Analysis of Vascular Growth, Maturation and Injury in the Brain
The distinct organization of the brain’s vasculature ensures the adequate delivery of oxygen and nutrients during development and adulthood. Acute and chronic pathological changes of the vascular system have been implicated in many neurological disorders including stroke and dementia. Here, we describe a fast, automated method that allows the highly reproducible, quantitative assessment of distinct vascular parameters and their changes based on the open source software Fiji (ImageJ). In particular, we developed a practical guide to reliably measure aspects of growth, repair and maturation of the brain’s vasculature during development and neurovascular disease in mice and humans. The script can be used to assess the effects of different external factors including pharmacological treatments or disease states. Moreover, the procedure is expandable to blood vessels of other organs and vascular in vitro models. © Copyright © 2020 Rust, Kirabali, Grönnert, Dogancay, Limasale, Meinhardt, Werner, Laviña, Kulic, Nitsch, Tackenberg and Schwab
Mental health state and its determinants in German university students across the COVID-19 pandemic : findings from three repeated cross-sectional surveys between 2019 and 2021
Background: Students were at an increased risk for elevated mental symptoms during the first year of the COVID-19 pandemic compared to pre-pandemic levels. As universities remained closed much longer than anticipated, the mental burden was expected to persist through the second year of the pandemic. The current study aimed to investigate the prevalence of mental distress from 2019 through 2021 and identify risk factors for elevated mental burden, focusing on gender.
Methods: We analyzed three cross-sectional online surveys among students at the University of Mainz, conducted in 2019 (n = 4,351), 2020 (n = 3,066), and 2021 (n = 1,438). Changes in the prevalence of depressive symptoms, anxiety, suicidal ideation, and loneliness were calculated using Pearson's chi-square tests and analyses of variance. Multiple linear regressions yielded associated risk factors.
Results: The proportion of students with clinically relevant depressive symptoms was significantly higher during the pandemic (38.9% in 2020, and 40.7% in 2021), compared to pre-pandemic (29.0% in 2019). Similarly, more students reported suicidal ideation and generalized anxiety during the pandemic with a peak in the second pandemic year (2021). The level of loneliness was significantly higher in 2020, compared to 2019, and remained at a high level in 2021 (p < 0.001, η2p
= 0.142). Female and diverse/open gender, being single, living alone, and being a first-year student were identified as risk factors associated with mental burden during the pandemic.
Discussion: Mental burdens remained elevated among students through the second year of the pandemic and were associated with socio-demographic risk factors and pandemic-related concerns. Future research should monitor recovery and evaluate the need for psychosocial support
Performance Verification of the FlashCam Prototype Camera for the Cherenkov Telescope Array
The Cherenkov Telescope Array (CTA) is a future gamma-ray observatory that is
planned to significantly improve upon the sensitivity and precision of the
current generation of Cherenkov telescopes. The observatory will consist of
several dozens of telescopes with different sizes and equipped with different
types of cameras. Of these, the FlashCam camera system is the first to
implement a fully digital signal processing chain which allows for a traceable,
configurable trigger scheme and flexible signal reconstruction. As of autumn
2016, a prototype FlashCam camera for the medium-sized telescopes of CTA nears
completion. First results of the ongoing system tests demonstrate that the
signal chain and the readout system surpass CTA requirements. The stability of
the system is shown using long-term temperature cycling.Comment: 5 pages, 13 figures, Proceedings of the 9th International Workshop on
Ring Imaging Cherenkov Detectors (RICH 2016), Lake Bled, Sloveni
FlashCam: a fully-digital camera for the medium-sized telescopes of the Cherenkov Telescope Array
The FlashCam group is currently preparing photomultiplier-tube based cameras
proposed for the medium-sized telescopes (MST) of the Cherenkov Telescope Array
(CTA). The cameras are designed around the FlashCam readout concept which is
the first fully-digital readout system for Cherenkov cameras, based on
commercial FADCs and FPGAs as key components for the front-end electronics
modules and a high performance camera server as back-end. This contribution
describes the progress of the full-scale FlashCam camera prototype currently
under construction, as well as performance results also obtained with earlier
demonstrator setups. Plans towards the production and implementation of
FlashCams on site are also briefly presented.Comment: 8 pages, 6 figures. In Proceedings of the 34th International Cosmic
Ray Conference (ICRC2015), The Hague, The Netherlands. All CTA contributions
at arXiv:1508.0589
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