4,908 research outputs found
Decomposition pathways of 13C-depleted leaf litter in forest soils of the Swiss Jura
Decomposition of leaf litter and its incorporation into the mineral soil are key components of the C cycle in forest soils. In a 13C tracer experiment, we quantified the pathways of C from decomposing leaf litter in calcareous soils of a mixed beech forest in the Swiss Jura. Moreover, we assessed how important the cold season is for the decomposition of freshly fallen leaves. The annual C loss from the litter layer of 69-77% resulted mainly from the C mineralization (29-34% of the initial litter C) and from the transfer of litter material to the deeper mineral soil (>4cm) by soil fauna (30%). Although only 4-5% of the initial litter C was leached as dissolved organic carbon (DOC), this pathway could be important for the C sequestration in soils in the long term: The DOC leached from the litter layer was mostly retained (95%) in the first 5cm of the mineral soil by both physico-chemical sorption and biodegradation and, thus, it might have contributed significantly to the litter-derived C recovered in the heavy fraction (>1.6gcm−3) at 0-4cm depth (4% of the initial litter C). About 80% of the annual DOC leaching from the litter layer occurred during the cold season (Nov-April) due to an initial DOC flush of water-soluble substances. In contrast, the litter mineralization in winter accounted for only 25% of the annual C losses through CO2 release from the labelled litter. Nevertheless, the highest contributions (45-60%) of litter decay to the heterotrophic soil respiration were observed on warm winter days when the mineral soil was still cold and the labile litter pool only partly mineralized. Our 13C tracing also revealed that: (1) the fresh litter C only marginally primed the mineralization of older SOM (>1year); and (2) non-litter C, such as throughfall DOC, contributed significantly to the C fluxes from the litter layer since the microbial biomass and the DOC leached from the litter layer contained 20-30% and up to 60% of unlabelled C, respectively. In summary, our study shows that significant amounts of recent leaf litter C (<1year) are incorporated into mineral soils and that the cold season is clearly less important for the litter turnover than the warm season in this beech forest ecosyste
Multiskalige Modellierung von Lithium-Ionen-Batterien
In dieser Arbeit werden Modellansätze für die internen Prozesse großformatiger Lithium-Ionen-Batterien entwickelt sowie experimentell parametriert und validiert. Damit werden sowohl die elektrochemischen Verluste in den Elektroden untersucht als auch deren Wechselwirkung mit der Potential- und Temperaturverteilung großformatiger Zellen. Darüber hinaus werden zulässige Betriebsbedingungen der Zellen identifiziert sowie Potentiale hinsichtlich der Leistungs- und Energiedichtesteigerung aufgezeigt
Realization of a Self-triggered Detector for the Radio Emission of Cosmic Rays
When an UHECR enters the atmosphere, it emits a radio pulse which can be used for detection. The main problem of this new detection method is the poor signal to noise level. This thesis describes the development of an adaptive digital filter to remove radio frequency interference (RFI) in real-time, followed by a self trigger to reject transient noise. The system was implemented in FPGA hardware, tested, and commissioned in the frame of the AERA experiment at the Pierre Auger Observatory
Charge Transfer Parameters of NiMnCo Cathodes Evaluated by a Transmission Line Modeling Approach
The performance of lithium‐ion batteries can be analyzed and improved by appropriate electrochemical models. A challenging yet crucial part is the parameterization of these models. Until now, the literature has incompletely investigated and cited the charge transfer process parameters describing the lithium transfer between the active material particles in the electrode and the liquid electrolyte. Herein, a novel approach is presented for obtaining these charge transfer parameters. The well‐established experimental methods of electrochemical impedance spectroscopy and focused ion beam tomography are applied. By introducing both experimental results into a transmission line model, a reliable determination of the charge transfer parameters j, k, and r can be achieved. The new approach is validated by comparing the results of four cathodes, all containing the state‐of‐the‐art active material NiMnCo (NMC), but with different microstructures and/or stoichiometries
Emberger Syndrome – A Family History Over 3 Generations
# Introduction
Haploinsufficiency of _GATA2_ leads to impaired genesis and function of hematopoietic stem and progenitor cells, resulting in impairment of all subsequent blood cell lineages. Germline mutations in _GATA2_ are transmitted by autosomal-dominant inheritance. Leading clinical symptoms of _GATA2_ deficiency syndromes are immunodeficiency, infections (mainly nontuberculous mycobacteria and human papillomavirus), predisposition to myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML), pulmonary alveolar proteinosis (PAP) and primary lymphedema. _GATA2_ mutations underlie not only Emberger syndrome (primary lymphedema and MDS), but also other syndromes like monocytopenia and mycobacterial infections syndrome (MonoMAC), dendritic cell/monocytopenia/natural killer (NK)-cell/B-cell lymphoid deficiency (DCML) and familial MDS/AML syndrome. We report the history of a Swiss family with Emberger syndrome extending over three generations. In addition, a review of the literature on _GATA2_ deficiencies is provided.
# Methods
Based on a general practitioner's observation of father and son sharing similar declined blood values and lymphedema, we examined the whole family for the presence of _GATA2_ mutation and a possible genotype-phenotype correlation. Publications on _GATA2_ deficiencies were researched on the PubMed database.
# Results
Six family members were diagnosed with _GATA2_ mutation, demonstrating individually variable penetrance and diversity of leading symptoms.
# Conclusion
Careful investigation of personal and family history, as well as meticulous examination, led to suspicion of the rare diagnosis of familial Emberger syndrome. Early diagnosis is mandatory for appropriate disease management
Multiskalige Modellierung von Lithium-Ionen-Batterien
In this work, model approaches for the internal processes of large-format lithium-ion batteries are developed, experimentally parameterized, and validated. The electrochemical losses in the electrode’s microstructure are investigated as well as their interaction with the heterogeneous potential and temperature distribution of large-format cells. In addition, permissible operating conditions of the cells are identified as well as potentials with regard to increasing power and energy density
'Flying high?'-Jump from a height in a 'Spice' high? : A case report on the synthetic cannabinoid 5F-MDMB-P7AICA
Regarding the high potency of synthetic cannabinoids (SC), many intoxications and
fatal cases are reported in literature. Here, we report on a fatality with 5F-MDMBP7AICA contributing to the occurrence of death. A 31-year-old man died 10 h after
he fell from the rooftop of a house. Police investigations revealed that he had consumed a ‘legal high’ herbal blend some hours earlier. An initial toxicological screening
for new psychoactive substances (NPS) was negative. One year after, the analysis of
confiscated drug samples revealed the SC 5F-MDMB-P7AICA being unknown at the
time of the first investigations. Hence, post-mortem specimens were retrospectively
analysed for 5F-MDMB-P7AICA and its dimethylbutanoic acid (DBA) metabolite.
Lung, liver, kidney and bile fluid (BF) of the decedent were analysed following solidphase extraction and standard addition, heart blood (HB) and peripheral blood (PB) by
fully validated liquid–liquid extraction and protein precipitation methods. Additionally,
hair specimens were analysed to examine a possible chronic consumption of the
SC. All specimens were analysed by liquid–chromatography tandem mass spectrometry. 5F-MDMB-P7AICA was detected in HB (0.69 ng/ml), PB (1.2 ng/ml) and hair.
DBA was found in HB (46 ng/ml) and PB (5.7 ng/ml) and could additionally be identified in liver and kidney (approximately 4–5 ng/g), lung (approximately 12 ng/g) and
BF (approximately 60 ng/g). Compared with the parent compound, much higher concentrations of DBA were quantified. This case shows that drugs found at the scene
can provide helpful initial information for further toxicological screenings in biological
samples, especially when there is evidence of NPS consumption
A multi scale multi domain model for large format lithium-ion batteries
A multi scale multi domain (MSMD) model for large format lithium-ion battery (LIB) cells is presented. In our approach the homogenization is performed on two scales (i) from the particulate electrodes to homogenized electrode materials using an extended Newman model and (ii) from individual cell layer materials to a homogenized battery material with anisotropic electrical and thermal transport properties. Both intertwined homogenizations are necessary for considering electrochemical-thermal details related to microstructural and material features of electrode and electrolyte layers at affordable computational costs. Simulation results validate the MSMD model compared to the homogenized Newman model for isothermal cases. The strength of the MSMD model is demonstrated for non-isothermal conditions, namely for a 120 Ah cell discharged with four different cooling concepts: (i) without cooling (ii) with a base plate cooling (iii) with a tab cooling and (iv) with a side cooling. As one result, temperature gradients cause a local peak discharge up to 2.8 C for a global 2 C discharge rate
Integrase-deficient lentiviral vectors mediate efficient gene transfer to human vascular smooth muscle cells with minimal genotoxic risk
We have previously shown that injury-induced neointima formation was rescued by adenoviral-Nogo-B gene delivery. Integrase-competent lentiviral vectors (ICLV) are efficient at gene delivery to vascular cells but present a risk of insertional mutagenesis. Conversely, integrase-deficient lentiviral vectors (IDLV) offer additional benefits through reduced mutagenesis risk, but this has not been evaluated in the context of vascular gene transfer. Here, we have investigated the performance and genetic safety of both counterparts in primary human vascular smooth muscle cells (VSMC) and compared gene transfer efficiency and assessed the genotoxic potential of ICLVs and IDLVs based on their integration frequency and insertional profile in the human genome. Expression of enhanced green fluorescent protein (eGFP) mediated by IDLVs (IDLV-eGFP) demonstrated efficient transgene expression in VSMCs. IDLV gene transfer of Nogo-B mediated efficient overexpression of Nogo-B in VSMCs, leading to phenotypic effects on VSMC migration and proliferation, similar to its ICLV version and unlike its eGFP control and uninfected VSMCs. Large-scale integration site analyses in VSMCs indicated that IDLV-mediated gene transfer gave rise to a very low frequency of genomic integration compared to ICLVs, revealing a close-to-random genomic distribution in VSMCs. This study demonstrates for the first time the potential of IDLVs for safe and efficient vascular gene transfer
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