42 research outputs found
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Lightweight polymer-carbon composite current collector for lithium-ion batteries
A hermetic dense polymer-carbon composite-based current collector foil (PCCF) for lithium-ion battery applications was developed and evaluated in comparison to state-of-the-art aluminum (Al) foil collector. Water-processed LiNi0.5Mn1.5O4 (LMNO) cathode and Li4Ti5O12 (LTO) anode coatings with the integration of a thin carbon primer at the interface to the collector were prepared. Despite the fact that the laboratory manufactured PCCF shows a much higher film thickness of 55 µm compared to Al foil of 19 µm, the electrode resistance was measured to be by a factor of 5 lower compared to the Al collector, which was attributed to the low contact resistance between PCCF, carbon primer and electrode microstructure. The PCCF-C-primer collector shows a sufficient voltage stability up to 5 V vs. Li/Li+ and a negligible Li-intercalation loss into the carbon primer. Electrochemical cell tests demonstrate the applicability of the developed PCCF for LMNO and LTO electrodes, with no disadvantage compared to state-of-the-art Al collector. Due to a 50% lower material density, the lightweight and hermetic dense PCCF polymer collector offers the possibility to significantly decrease the mass loading of the collector in battery cells, which can be of special interest for bipolar battery architectures. © 2020 by the authors. Licensee MDPI, Basel, Switzerland
Information and Arena: The Dual Function of the News Media for Political Elites
Abstract: How do individual politicians use the news media to reach their political goals? This study addresses the question by proposing an actor-centered, functional approach. We distinguish 2 essential functions (and subfunctions) the mass media have for political elites. The media are a source of information; politicians depend on it for pure information and they can profit from the momentum generated by media information. The media also are an arena elites need access to in order to promote themselves and their issues. These 2 functions offer certain politicians a structural advantage over others and, hence, are relevant for the power struggle among political elites. A systematic functional account enables comparisons of the role of the media across politicians and political systems
Identification of genetic variants associated with Huntington's disease progression: a genome-wide association study
Background Huntington's disease is caused by a CAG repeat expansion in the huntingtin gene, HTT. Age at onset has been used as a quantitative phenotype in genetic analysis looking for Huntington's disease modifiers, but is hard to define and not always available. Therefore, we aimed to generate a novel measure of disease progression and to identify genetic markers associated with this progression measure. Methods We generated a progression score on the basis of principal component analysis of prospectively acquired longitudinal changes in motor, cognitive, and imaging measures in the 218 indivduals in the TRACK-HD cohort of Huntington's disease gene mutation carriers (data collected 2008–11). We generated a parallel progression score using data from 1773 previously genotyped participants from the European Huntington's Disease Network REGISTRY study of Huntington's disease mutation carriers (data collected 2003–13). We did a genome-wide association analyses in terms of progression for 216 TRACK-HD participants and 1773 REGISTRY participants, then a meta-analysis of these results was undertaken. Findings Longitudinal motor, cognitive, and imaging scores were correlated with each other in TRACK-HD participants, justifying use of a single, cross-domain measure of disease progression in both studies. The TRACK-HD and REGISTRY progression measures were correlated with each other (r=0·674), and with age at onset (TRACK-HD, r=0·315; REGISTRY, r=0·234). The meta-analysis of progression in TRACK-HD and REGISTRY gave a genome-wide significant signal (p=1·12 × 10−10) on chromosome 5 spanning three genes: MSH3, DHFR, and MTRNR2L2. The genes in this locus were associated with progression in TRACK-HD (MSH3 p=2·94 × 10−8 DHFR p=8·37 × 10−7 MTRNR2L2 p=2·15 × 10−9) and to a lesser extent in REGISTRY (MSH3 p=9·36 × 10−4 DHFR p=8·45 × 10−4 MTRNR2L2 p=1·20 × 10−3). The lead single nucleotide polymorphism (SNP) in TRACK-HD (rs557874766) was genome-wide significant in the meta-analysis (p=1·58 × 10−8), and encodes an aminoacid change (Pro67Ala) in MSH3. In TRACK-HD, each copy of the minor allele at this SNP was associated with a 0·4 units per year (95% CI 0·16–0·66) reduction in the rate of change of the Unified Huntington's Disease Rating Scale (UHDRS) Total Motor Score, and a reduction of 0·12 units per year (95% CI 0·06–0·18) in the rate of change of UHDRS Total Functional Capacity score. These associations remained significant after adjusting for age of onset. Interpretation The multidomain progression measure in TRACK-HD was associated with a functional variant that was genome-wide significant in our meta-analysis. The association in only 216 participants implies that the progression measure is a sensitive reflection of disease burden, that the effect size at this locus is large, or both. Knockout of Msh3 reduces somatic expansion in Huntington's disease mouse models, suggesting this mechanism as an area for future therapeutic investigation
The V471A polymorphism in autophagy-related gene ATG7 modifies age at onset specifically in Italian Huntington disease patients
The cause of Huntington disease (HD) is a polyglutamine repeat expansion of more than 36 units in the huntingtin protein, which is inversely correlated with the age at onset of the disease. However, additional genetic factors are believed to modify the course and the age at onset of HD. Recently, we identified the V471A polymorphism in the autophagy-related gene ATG7, a key component of the autophagy pathway that plays an important role in HD pathogenesis, to be associated with the age at onset in a large group of European Huntington disease patients. To confirm this association in a second independent patient cohort, we analysed the ATG7 V471A polymorphism in additional 1,464 European HD patients of the “REGISTRY” cohort from the European Huntington Disease Network (EHDN). In the entire REGISTRY cohort we could not confirm a modifying effect of the ATG7 V471A polymorphism. However, analysing a modifying effect of ATG7 in these REGISTRY patients and in patients of our previous HD cohort according to their ethnic origin, we identified a significant effect of the ATG7 V471A polymorphism on the HD age at onset only in the Italian population (327 patients). In these Italian patients, the polymorphism is associated with a 6-years earlier disease onset and thus seems to have an aggravating effect. We could specify the role of ATG7 as a genetic modifier for HD particularly in the Italian population. This result affirms the modifying influence of the autophagic pathway on the course of HD, but also suggests population-specific modifying mechanisms in HD pathogenesis
ED Patients with Prolonged Complaints and Repeat ED Visits Have an Increased Risk of Depression
Introduction: The objective of this study was to explore associations between presenting chief complaints of prolonged symptomatology, patient usage of the emergency department (ED), and underlying depression so that emergency physicians may better target patients for depression screening.Methods: A convenience sample of ED patients were administered the Beck Depression Inventory-II (BDI-II) to assess for depression. We correlated completed BDI-II surveys to patient information including demographics, pertinent history of present illness information, and past medical history.Results: Out of 425 participants screened, we identified complaints of two weeks or longer in 92 patients (22%). Of these patients, mild to severe depression was recognized in over half of the population (47), yet only nine patients reported a prior depression diagnosis. These 92 patients also visited the ED three times as frequently as those patients with more acute complaints (p<0.001). Finally, our study showed that patients with mild to severe depression had three times as many ED visits compared to patients with minimal or no depression (p<0.001).
Conclusion: Patients with complaints of symptomatology two weeks or longer are more likely to have underlying depression when presenting to the ED. Patients with three or more ED visits within the past year also have a greater incidence of underlying depression. We found a strong correlation between complaints with symptomatology of two weeks or longer and multiple ED visits, in which underlying depression may have contributed to these patients’ ED visits. [West J Emerg Med. 2016;17(5)613-616.]
RAGE mediates S100A4-induced cell motility via MAPK/ERK and hypoxia signaling and is a prognostic biomarker for human colorectal cancer metastasis
Survival of colorectal cancer patients is strongly dependent on development of distant metastases. S100A4 is a prognostic biomarker and inducer for colorectal cancer metastasis. Besides exerting intracellular functions, S100A4 is secreted extracellularly. The receptor for advanced glycation end products (RAGE) is one of its interaction partners. The impact of the S100A4-RAGE interaction for cell motility and metastasis formation in colorectal cancer has not been elucidated so far. Here we demonstrate the RAGE-dependent increase in migratory and invasive capabilities of colorectal cancer cells via binding to extracellular S100A4. We show the direct interaction of S100A4 and RAGE, leading to hyperactivated MAPK/ERK and hypoxia signaling. The S100A4-RAGE axis increased cell migration (P<0.005) and invasion (P<0.005), which was counteracted with recombinant soluble RAGE and RAGE-specific antibodies. In colorectal cancer patients, not distantly metastasized at surgery, high RAGE expression in primary tumors correlated with metachronous metastasis, reduced overall (P=0.022) and metastasis-free survival (P=0.021).
In summary, interaction of S100A4-RAGE mediates S100A4-induced colorectal cancer cell motility. RAGE by itself represents a biomarker for prognosis of colorectal cancer. Thus, therapeutic approaches targeting RAGE or intervening in S100A4-RAGE-dependent signaling early in tumor progression might represent alternative strategies restricting S100A4-induced colorectal cancer metastasis
Channelrhodopsin-1 Phosphorylation Changes with Phototactic Behavior and Responds to Physiological Stimuli in Chlamydomonas
Maximizing profit on New England organic dairy farms: An economic comparison of 4 total mixed rations for organic Holsteins and Jerseys
The objective of these experiments was to compare 4 total mixed rations fed to USDA-certified organic dairy cows in New England. Forty-eight Jersey cows from the University of New Hampshire (UNH) and 64 Holstein cows from the University of Maine (UMaine) were assigned to a 2 x 2 factorial arrangement of treatments testing the main effects of corn silage versus grass silage as the forage base and commodity concentrates versus a complete pelleted concentrate mixture. Treatment diets were fed as a total mixed ration for 8 wk during the winter and spring months of 2007, 2008, and 2009. Milk yield, component, and quality data were recorded and used to calculate the value of the milk produced for each cow. The dry matter intake (DMI) was recorded and used to calculate the average cost per cow per day of each diet. Income over feed costs were calculated for each diet using milk value and feed cost data. Feed cost and income over feed cost data were resampled using bootstrap methodology to examine potential patterns. Milk yield, milk fat and true protein concentrations, and SCC were similar among treatments. Cows at UNH fed corn silage tended to have higher DMI and lower milk urea nitrogen than did cows fed grass silage, whereas cows fed pellets had higher DMI than cows fed commodities. Cows at UNH fed commodities tended to have higher body condition scores than those fed pellets. Cows at UMaine fed commodities tended to have higher DMI than did cows fed pellets, and cows fed corn silage had lower milk urea nitrogen than did cows fed grass silage. Body weights and body condition scores were not different for cows at UMaine. Feed costs were significantly higher for corn silage diets and diets at UNH containing pellets, but not at UMaine. The calculated value of the milk and income over feed costs did not differ among treatments at either university. Bootstrap replications indicated that the corn silage with commodities diet generally had the highest feed cost at both UNH and UMaine, whereas grass silage diets containing commodities generally had the lowest cost. In contrast, the grass silage with commodities diets had the highest income over feed cost in the majority of the replications at both UNH and UMaine replications, whereas the corn silage with commodities diets had the lowest rank. Similar results were observed when forage prices were increased or decreased by 5, 10, and 25% above or below the actual feed price. Feeding a grass silage-based diet supplemented with commodity concentrates may have an economic advantage for dairy producers in New England operating under an organic system of production
PET Scintillator Arrangement on digital SiPMs
The common way to build a PET detector is to place an array of scintillator elements on top of a photo detector. In order to achieve high spatial resolution the scintillator footprints are often smaller than the pixel size of the photodetector. This requires light sharing and some kind of algorithm like Anger-Logic in order to identify the correct scintillator element in which the event took place. The digital Silicon Photomultiplier DPC3200-22-44 (Philips Digital Photon Counting) is a fully digital photo sensor device [1]. Each pixel consists of 3200 individual micro cells which are charged and read out under digital control. The device (Tile) is organized as an array of 8 by 8 pixels each of 3.9x3.9 mm2 size and is realized as a PCB equipped with 16 dice. One die provides four pixels together with the corresponding triggering, validation and readout electronics. Depending on the configuration the detection of an event on one die can cause the other dice to transmit their data as well (neighbor logic). The obvious solution of using neighbor logic and a scintillator matrix with light guide covering the whole tile shows some drawbacks. After each event all 16 dice will be busy and all pixels need to be read out. This results in increased dead time and a lot of data. Furthermore it turned out that sometimes pixels are missing because dice were already busy and could not transmit data when the event was detected. This will complicate the identification of the event position. A better performance can be obtained when the light is shared only within the four pixels of each die and the dice work independent from each other. We investigated the positioning capability of different scintillator matrices and light guides. These are arranged in such a way, that a single die can only receive the light from a 4 by 4 array of LYSO crystals which covers exactly the die dimensions. The results show that clear crystal identification can be achieved with such an arrangement. [1] Haemisch et al., Physics Procedia 37 (2012) 154
WissenschaftlerInnen als Kommunikatoren
Im Fokus des Kapitels steht die Beteiligung von WissenschaftlerInnen an der medialen öffentlichen Kommunikation. Befragungen zeigen, dass die meisten Wissenschaftler Wissenschaftskommunikation für wichtig halten, Nutzen damit verbinden und sich auch selbst daran beteiligen. Wissenschaftler mit Medienerfahrung äußern sich überwiegend positiv oder ambivalent zu ihren Medienkontakten. Während Normen der Scientific Community weiterhin relevant dafür sind, welcher Wissenschaftler sich wie, wann und zu welchen Themen öffentlich äußert, werden Hochschulen und außeruniversitäre Forschungseinrichtungen als regulierender Kontext zunehmend bedeutsamer: Pressestellen erwarten von Wissenschaftlern Inhalte für die Organisationskommunikation, vermitteln Kontakte zu Journalisten und versuchen, die öffentlichen Kommunikationsaktivitäten von Wissenschaftlern einerseits zu fördern, andererseits aber auch darauf einzuwirken, dass sie mit den Organisationszielen kompatibel sind. Der wahrgenommene Nutzen öffentlicher Sichtbarkeit und die damit zusammenhängende strategische motivierte Medienorientierung von Wissenschaftsorganisationen und Wissenschaftlern bringt Verführungen mit sich, die potentiell die inhaltliche Qualität öffentlicher Kommunikation gefährden