943 research outputs found

    Topological constraints on stabilized flux vacua

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    We study the influence of four-form fluxes on the stabilization of the Kahler moduli in M-theory compactified on a Calabi-Yau four-fold. We find that, under certain non-degeneracy condition on the flux, M5-instantons of a new topological type generate a superpotential. The existence of such an instanton restricts possible four-folds for which the stabilization by this mechanism is expected. These topological constraints on the background are different from the previously known constraints, derived from the flux-free analysis of the nonperturbative effects.Comment: 10 pages, harvmac, references adde

    Caspase-8 controls the gut response to microbial challenges by Tnf-alpha-dependent and independent pathways

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    Objectives: Intestinal epithelial cells (IEC) express toll-like receptors (TLR) that facilitate microbial recognition. Stimulation of TLR ligands induces a transient increase in epithelial cell shedding, a mechanism that serves the antibacterial and antiviral host defence of the epithelium and promotes elimination of intracellular pathogens. Although activation of the extrinsic apoptosis pathway has been described during inflammatory shedding, its functional involvement is currently unclear. Design: We investigated the functional involvement of caspase-8 signalling in microbial-induced intestinal cell shedding by injecting Lipopolysaccharide (LPS) to mimic bacterial pathogens and poly(I:C) as a probe for RNA viruses in vivo. Results: TLR stimulation of IEC was associated with a rapid activation of caspase-8 and increased epithelial cell shedding. In mice with an epithelial cell-specific deletion of caspase-8 TLR stimulation caused Rip3-dependent epithelial necroptosis instead of apoptosis. Mortality and tissue damage were more severe in mice in which IECs died by necroptosis than apoptosis. Inhibition of receptor-interacting protein (Rip) kinases rescued the epithelium from TLR-induced gut damage. TLR3-induced necroptosis was directly mediated via TRIF-dependent pathways, independent of Tnf-α and type III interferons, whereas TLR4-induced tissue damage was critically dependent on Tnf-α. Conclusions: Together, our data demonstrate an essential role for caspase-8 in maintaining the gut barrier in response to mucosal pathogens by permitting inflammatory shedding and preventing necroptosis of infected cells. These data suggest that therapeutic strategies targeting the cell death machinery represent a promising new option for the treatment of inflammatory and infective enteropathies

    Influence of enzymes and ascorbic acid on dough rheology and wheat bread quality

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    The combined action of ascorbic acid and two commercial enzymatic complexes containing amylase and xylanase/amylase was analyzed to determine their effects on dough rheology and bread quality. Seven bread formulations containing different concentrations of these improvers were used in the analysis. The rheological properties of each dough formulation were determined by moisture, gluten and farinograph tests. The breads were also characterized in general aspect - especially shelf-life - based on the presence of fungi. The dough rheology results showed that the formulation developed in the presence of 0.01% xylanase/amylase and 200 ppm of ascorbic acid was more efficient. Improved shelf-life was obtained from the formulations containing xylanase. The results showed that some technological characteristics of dough rheology and gluten index produced from the combination of these improvers can indicate in order to obtain specific features of the bread.Keywords: Food biotechnology, xylanase, amylase, dough properties, bread improver

    Integrated Planning of Multi-energy Grids: Concepts and Challenges

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    In order to meet ever-stricter climate targets and achieve the eventual decarbonization of the energy supply of German industrial metropolises, the focus is on gradually phasing out nuclear power, then coal and gas combined with the increased use of renewable energy sources and employing hydrogen as a clean energy carrier. While complete electrification of the energy supply of households and the transportation sector may be the ultimate goal, a transitional phase is necessary as such massive as well as rapid expansion of the electrical distribution grid is infeasible. Additionally, German industries have expressed their plans to use hydrogen as their primary strategy in meeting carbon targets. This poses challenges to the existing electrical, gas, and heating distribution grids. It becomes necessary to integrate the planning and developing procedures for these grids to maximize efficiencies and guarantee security of supply during the transition. The aim of this paper is thus to highlight those challenges and present novel concepts for the integrated planning of the three grids as one multi-energy grid.Comment: NEIS 2022; Conference on Sustainable Energy Supply and Energy Storage System

    An acetylcholine alpha7 positive allosteric modulator rescues a schizophrenia-associated brain endophenotype in the 15q13.3 microdeletion, encompassing CHRNA7

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    The 15q13.3 microdeletion copy number variation is strongly associated with schizophrenia and epilepsy. The CHRNA7 gene, encoding nicotinic acetylcholine alpha 7 receptors (nAChA7Rs), is hypothesized to be one of the main genes in this deletion causing the neuropsychiatric phenotype. Here we used a recently developed 15q13.3 microdeletion mouse model to explore whether an established schizophrenia-associated connectivity phenotype is replicated in a murine model, and whether positive modulation of nAChA7 receptor might pharmacologically normalize the connectivity patterns. Resting-state fMRI data were acquired from male mice carrying a hemizygous 15q13.3 microdeletion (N=9) and from wild-type mice (N=9). To study the connectivity profile of 15q13.3 mice and test the effect of nAChA7 positive allosteric modulation, the 15q13.3 mice underwent two imaging sessions, one week apart, receiving a single intraperitoneal injection of either 15 mg/kg Lu AF58801 or saline. The control group comprised wild-type mice treated with saline. We performed seed-based functional connectivity analysis to delineate aberrant connectivity patterns associated with the deletion (15q13.3 mice (saline treatment) versus wild-type mice (saline treatment)) and their modulation by Lu AF58801 (15q13.3 mice (Lu AF58801 treatment) versus 15q13.3 mice (saline treatment)). Compared to wild-type mice, 15q13.3 mice evidenced a predominant hyperconnectivity pattern. The main effect of Lu AF58801 was a normalization of elevated functional connectivity between prefrontal and frontal, hippocampal, striatal, thalamic and auditory regions. The strongest effects were observed in brain regions expressing nAChA7Rs, namely hippocampus, cerebral cortex and thalamus. These effects may underlie the antiepileptic, pro-cognitive and auditory gating deficit-reversal effects of nAChA7R stimulation

    Detekcja rozsianych komórek nowotworowych w szpiku kostnym u pacjentek z rakiem piersi z zastosowaniem nowej metody molekularnej

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    Objectives: Numerous studies have shown that the presence of clinically occult disseminated tumor cells (DTC) in the bone marrow (BM) of breast cancer patients is associated with an unfavourable clinical outcome. Immunocytochemistry (ICC) remains the gold standard for their detection. Assays based on RT-PCR are available; however, so far they have not been used for routine detection of DTC. Therefore, the purpose of this study was to evaluate a newly established molecular method for the detection of DTC. Materials and methods: BM aspirates from 405 patients were examined. Half of the samples were immediately inserted into ICC and the other half was examined with our newly established molecular method based on RT-PCR. Immunocytochemistry was performed according to the Consensus Recommendations of the German, Austrian, and Swiss Societies of Senology and ISHAGE Working Group (A45B-B3 antibody). RT-PCR was conducted as a one-step real-time assay. Cytokeratin 19-mRNA was amplifi ed. Results: In 142 of 405 (35%) aspirates disseminated tumor cells were detected by RT-PCR. In 34% of patients DTC were detected by ICC. 48% of the BM samples were positive by at least one method. In 73% of the patients identical results were obtained (pCel pracy: Liczne badania pokazały, że obecność rozsianych komórek nowotworowych (RKN) w szpiku kostnym u pacjentek chorych na raka piersi związana jest z niekorzystnym rokowaniem. Metodą standardową w oznaczaniu RKN jest immunocytochemia (ICC). Metody molekularne, takie jak RT-PCR, są również dostępne, dotychczas jednak nie są one stosowane rutynowo w detekcji RKN. Celem pracy była ewaluacja nowej metody molekularnej do oznaczania RKN. Materiał i metody: Zbadane zostały aspiraty szpiku kostnego pochodzące od 405 pacjentek z rakiem piersi. Połowę pobranego szpiku badano immunocytochemicznie, drugą połowę - nową metodą molekularną opartą na technologii RT-PCR. Immunocytochemię przeprowadzano zgodnie z zaleceniami Niemieckiego, Austriackiego i Szwajcarskiego Towarzystwa Chorob Piersi oraz grupy ISHAGE (przeci ciało A45B-B3). RT-PCR przeprowadzano w konwencji One-step, amplifi kacja mRNA cytokeratyny 19 rejestrowana była w czasie rzeczywistym („real-time”). Wyniki: W 142 z 405 (35%) pobranych szpików wykryto rozsiane komórki nowotworowe metodą RT-PCR. U 34% pacjentek wykryto RKN immunocytochemicznie. 48% aspiratów było pozytywnych przy użyciu przynajmniej jednej z metod. W 73% przypadków uzyskano ten sam wynik przy pomocy obu metod (

    COGNITION AND MOOD/BEHAVIOR IN HOME CARE ELDERLY

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    Objectives: to identify the sociodemographic characteristics; and to analyze the association of sociodemographic variables with functional systems related to cognition and mood/behavior of elderly people linked to Home Care.Method: cross-sectional, descriptive research, carried out with the participation of 108 elderly people linked to Home Care in the city of Santa Maria - RS - Brazil. We used a questionnaire of sociodemographic data and the Clinical and Functional Vulnerability Index IVCF-20. The association of the variables was analyzed using the chi-square test and independent samples test.Results: predominance of elderly females; mean age 78.7 ± 9.3 years; and low education and family income between 1 and 2 minimum wages. The most frequent morbidity was systemic arterial hypertension. No associations were found between the sociodemographic variables and the functional systems regarding cognition and mood/behavior.Conclusion: the importance of planning and interventions in the home environment is highlighted

    Foto identificación de marsopa espinosa, Phocoena spinipinnis, en el Canal Beagle, Tierra del Fuego, Argentina

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    La marsopa espinosa es endémica de Sudamérica. Se distribuye en aguas costeras desde el sur de Brasil hasta el norte de Perú, siendo Cabo de Hornos el límite más austral de su distribución. En Tierra del Fuego la especie se localiza en la costa atlántica y en el Canal Beagle. Existen pocos estudios sobre esta especie, posiblemente debido al comportamiento esquivo y errático que dificulta su observación en el hábitat. La foto identificación es una herramienta ampliamente utilizada para el estudio de mamíferos marinos, pero aún no se ha reportado su aplicación en marsopas espinosas. El objetivo de este trabajo fue probar la factibilidad de la técnica de foto identificación para el estudio de marsopa espinosa en el Canal Beagle. Para esto, se realizaron relevamientos en un semirrígido de 6m de eslora con dos motores de 60hp. Las salidas abarcaron el área entre Bahía Lapataia y Punta Segunda. Para registrar a los individuos se utilizaron dos cámaras: una Canon D7 con teleobjetivo de 18-270mm y una Nikon 7100 con teleobjetivo de 70-300mm. Se realizaron 18 salidas entre mayo de 2018 y julio de 2019, con un esfuerzo promedio de 5hs por salida. Se realizaron en condiciones de mar calmo (Beaufort 0-2) y se registraron datos ambientales, número de individuos, comportamiento y posición geográfica del grupo. Se avistaron 15 grupos. Se obtuvieron un total de 1914 fotos de las cuales 534 fueron consideradas para el análisis. Se lograron identificar 31 individuos utilizando marcas corporales y marcas en las aletas dorsales. 5 individuos fueron fotografiados en más de una oportunidad. El presente trabajo demuestra que esta técnica puede ser utilizada para el estudio de esta especie. Esta herramienta resultará útil para futuros estudios de estructura y dinámica social, patrones de movimientos y residencia de la población hallada en el Canal.Fil: Asplanato, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Wells, Randall S.. Chicago Zoological Society S Sarasota Dolphin Research; Estados UnidosFil: Torres, Monica Analia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Fioramonti, Nicolas Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Becker, Yamila Anabella. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Riccialdelli, Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Dellabianca, Natalia Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaXXXII Jornadas Argentinas de MastozoologíaPuerto MadrynArgentinaSociedad Argentina para el Estudio de los MamiferosCentro Nacional PatagónicoUniversidad Nacional de la Patagonia San Juan Bosc
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