3,346 research outputs found

    Quantic Analysis of the Adherence of a Gram-Negative Bacteria in A HEPA Filter

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    It is known that Gram-negative bacteria (GNB) are the most frequent bacteria in hospital units. It is also known that GNBs generate a greater number of nosocomial infections in critical areas. In the present work, the adhesion of the bacterial cell wall (BCW) to the compounds of the material layers of a high efficiency filter (HEPA) was analyzed. The analysis was carried out by means of molecular simulation and quantum chemistry. The BCW and HEPA molecules were designed using Hyperchem software for simulation. The calculations of the quantum interactions of the molecules were carried out using the theory of the electron transfer coefficient (ETC). It obtained from 4 to 6 compounds that are more likely to interact even as a chemical reaction. The compounds of the glass fibers are the ones that work best for the adhesion and destruction of the BCW

    The role of the LIRG and ULIRG phases in the evolution of Ks-selected galaxies

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    We investigate the role of the luminous infrared galaxy (LIRG) and ultra-luminous infrared galaxy (ULIRG) phases in the evolution of Ks-selected galaxies and, in particular, Extremely Red Galaxies (ERGs). With this aim, we compare the properties of a sample of 2905 Ks<21.5 (Vega mag) galaxies in the GOODS/CDFS with the sub-sample of those 696 sources which are detected at 24 microns. We find that LIRGs constitute 30% of the galaxies with stellar mass M>1x10^{11} Msun assembled at redshift z=0.5. A minimum of 65% of the galaxies with M>2.5x10^{11} Msun at z~2-3 are ULIRGs at those redshifts. 60% of the ULIRGs in our sample have the characteristic colours of ERGs. Conversely, 40% of the ERGs with stellar mass M>1.3x10^{11} Msun at 1.5<z<2.0 and a minimum of 52% of those with the same mass cut at 2.0<z<3.0 are ULIRGs. The average optical/near-IR properties of the massive ERGs at similar redshifts that are identified with ULIRGs and that are not have basically no difference, suggesting that both populations contain the same kind of objects in different phases of their lives. LIRGs and ULIRGs have an important role in galaxy evolution and mass assembly, and, although they are only able to trace a fraction of the massive (M>1x10^{11} Msun) galaxies present in the Universe at a given time, this fraction becomes very significant (>50%) at redshifts z>~2.Comment: Accepted for publication in A&A. 9 pages, 6 figure

    Photoelectrical reading in ZnO/Si NCs/p-Si resistive switching devices

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    The increasing need for efficient memories with integrated functionalities in a single device has led the electronics community to investigate and develop different materials for resistive switching (RS) applications. Among these materials, the well-known Si nanocrystals (NCs) have demonstrated to exhibit RS properties, which add to the wealth of phenomena that have been studied on this model material platform. In this work, we present ZnO/Si NCs/p-Si resistive switching devices whose resistance state can be electrically read at 0 V under the application of low-power monochromatic illumination. The presented effect is studied in terms of the inner structural processes and electronic physics of the device. In particular, the creation of conductive filaments through the Si NC multilayers induces a low-resistance path for photogenerated carriers to get extracted from the device, whereas in the pristine state charge extraction is strongly quenched due to the insulating nature of the NC-embedding SiO2 matrix. In addition, spectral inspection of the generated photocurrent allowed unveiling the role of Si NCs in the reported effect. Overall, the hereby shown results pave the way to obtain memories whose RS state can be read under low-power conditions

    GBA mutation promotes early mitochondrial dysfunction in 3D neurosphere models

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    Glucocerebrosidase (GBA) mutations are the most important genetic risk factor for the development of Parkinson disease (PD). GBA encodes the lysosomal enzyme glucocerebrosidase (GCase). Loss-of-GCase activity in cellular models has implicated lysosomal and mitochondrial dysfunction in PD disease pathogenesis, although the exact mechanisms remain unclear. We hypothesize that GBA mutations impair mitochondria quality control in a neurosphere model.We have characterized mitochondrial content, mitochondrial function and macroautophagy flux in 3D-neurosphere-model derived from neural crest stem cells containing heterozygous and homozygous N370SGBA mutations, under carbonyl cyanide-m-chlorophenyl-hydrazine (CCCP)- induced mitophagy.Our findings on mitochondrial markers and ATP levels indicate that mitochondrial accumulation occurs in mutant N370SGBA neurospheres under basal conditions, and clearance of depolarised mitochondria is impaired following CCCP-treatment. A significant increase in TFEB-mRNA levels, the master regulator of lysosomal and autophagy genes, may explain an unchanged macroautophagy flux in N370SGBA neurospheres. PGC1α-mRNA levels were also significantly increased following CCCP-treatment in heterozygote, but not homozygote neurospheres, and might contribute to the increased mitochondrial content seen in cells with this genotype, probably as a compensatory mechanism that is absent in homozygous lines.Mitochondrial impairment occurs early in the development of GCase-deficient neurons. Furthermore, impaired turnover of depolarised mitochondria is associated with early mitochondrial dysfunction.In summary, the presence of GBA mutation may be associated with higher levels of mitochondrial content in homozygous lines and lower clearance of damaged mitochondria in our neurosphere model

    Candidate planetary nebulae in the IPHAS photometric catalogue

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    Original article can be found at: http://www.aanda.org/ Copyright European Southern Observatory. DOI: 10.1051/0004-6361/200912002Context. We have carried out a semi-automated search for planetary nebulae (PNe) in the INT photometric H-alpha survey (IPHAS) catalogue. We present the PN search and the list of selected candidates. We cross correlate the selected candidates with a number of existing infrared galactic surveys in order to gain further insight into the nature of the candidates. Spectroscopy of a subset of objects is used to estimate the number of PNe present in the entire candidate list. Aims. The overall aim of the IPHAS PN project is to carry out a deep census of PNe in the northern Galactic plane, an area where PN detections are clearly lacking. Methods. The PN search is carried out on the IPHAS photometric catalogue. The candidate selection is based on the IPHAS and 2MASS/UKIDSS colours of the objects and the final candidate selection is made visually. Results. From the original list of ~600 million IPHAS detections we have selected a total of 1005 objects. Of these, 224 are known objects, leaving us with 781 PN candidates. Based on the initial follow-up spectroscopy, we expect the list to include very young and proto-PNe in addition to genuine, normal PNe (~16%) and emission line objects other than PNe. We present additional criteria to select the most probable PN candidates from our candidate list.Peer reviewe

    Quantic Analysis of Formation of a Biomaterial of Latex, Retinol, and Chitosan for Biomedical Applications

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    The present work shows the quantum theoretical analysis and practical tests for the formation of a homogeneous mixture with Latex (Lx), Chitosan (Qn) and Retinol (Rl), which work as possible biomaterial for regeneration of epithelial tissue. Lx, Qn, and Rl compounds molecules were designed through Hyperchem to get the coefficient of electrostatic potential calculations. The amounts used to create the biomaterial are minimum depending on the quantities of molecules used in chemical design. A positive calculation was obtained for the reaction of these three compounds and the formation of the biomaterial in physical checking theory etc

    Prepubertal Children With Metabolically Healthy Obesity or Overweight Are More Active Than Their Metabolically Unhealthy Peers Irrespective of Weight Status: GENOBOX Study

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    Background and Aim: The association of a metabolically healthy status with the practice of physical activity (PA) remains unclear. Sedentarism and low PA have been linked to increased cardiometabolic risk. The aim of this study was to evaluate the PA levels in metabolically healthy (MH) or unhealthy (MU) prepubertal children with or without overweight/obesity. Methods: A total 275 children (144 boys) with 9 ± 2 years old were selected for the GENOBOX study. PA times and intensities were evaluated by accelerometry, and anthropometry, blood pressure, and blood biochemical markers were analyzed. Children were considered to have normal weight or obesity, and further classified as MH or MU upon fulfillment of the considered metabolic criteria. Results: Classification resulted in 119 MH children (21% with overweight/obesity, referred to as MHO) and 156 MU children (47% with overweight/obesity, referred to as MUO). Regarding metabolic profile, MHO showed lower blood pressure levels, both systolic and diastolic and biochemical markers levels, such as glucose, Homeostatic Model Assessment of Insulin Resistance, triglycerides and higher HDL-c levels than MUO (P < 0.001). In addition, MHO children spent more time in PA of moderate intensity compared with MUO children. In relation to vigorous PA, MH normal weight (MHN) children showed higher levels than MUO children. Considering sex, boys spent more time engaged in moderate, vigorous, and moderate–vigorous (MV) PA than girls, and the number of boys in the MH group was also higher. Conclusion: Prepubertal MHO children are less sedentary, more active, and have better metabolic profiles than their MUO peers. However, all children, especially girls, should increase their PA engagement, both in terms of time and intensity because PA appears to be beneficial for metabolic health status itself. Copyright © 2022 Llorente-Cantarero, Leis, Rupérez, Anguita-Ruiz, Vázquez-Cobela, Flores-Rojas, González-Gil, Aguilera, Moreno, Gil-Campos and Bueno

    Bounding Helly numbers via Betti numbers

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    We show that very weak topological assumptions are enough to ensure the existence of a Helly-type theorem. More precisely, we show that for any non-negative integers bb and dd there exists an integer h(b,d)h(b,d) such that the following holds. If F\mathcal F is a finite family of subsets of Rd\mathbb R^d such that β~i(G)b\tilde\beta_i\left(\bigcap\mathcal G\right) \le b for any GF\mathcal G \subsetneq \mathcal F and every 0id/210 \le i \le \lceil d/2 \rceil-1 then F\mathcal F has Helly number at most h(b,d)h(b,d). Here β~i\tilde\beta_i denotes the reduced Z2\mathbb Z_2-Betti numbers (with singular homology). These topological conditions are sharp: not controlling any of these d/2\lceil d/2 \rceil first Betti numbers allow for families with unbounded Helly number. Our proofs combine homological non-embeddability results with a Ramsey-based approach to build, given an arbitrary simplicial complex KK, some well-behaved chain map C(K)C(Rd)C_*(K) \to C_*(\mathbb R^d).Comment: 29 pages, 8 figure

    Soluciones Creativas de Intervención (LUGH)

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    En este texto se puede encontrar información sobre los antecedentes del proyecto LUGH ITESO Soluciones creativas de intervención, así como los objetivos del trabajo que incluyen la vinculación entre empresas socialmente responsables con escenarios, comunidades, organizaciones u otros esfuerzos de la sociedad por mejorar su entorno. De este modo la empresa obtiene un beneficio en términos de posicionamiento, a la vez que produce un beneficio social tangible. Durante el período primavera 2016, se desarrollaron estrategias y piezas de comunicación para las organizaciones Plenitud de vida, Concertando México, Juntos por los demás y Capeltic. En este informe se incluye también la descripción del método de trabajo que el proyecto propone para la realización de estrategias de comunicación e intervención social
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