2,991 research outputs found
Spark Plug Simulation with the Use of Three Types of Fuels in Direct Injection Engines for the Evaluation of Polluting Factors
The present work has as main objective the use of a biofuel (EcopaÃs) in a direct injection vehicle, it is an option to reduce damage to health and the environment, for this a static thermal simulation will be done in the spark plug, to compare the results of the aforementioned software using On Board tests, in a 1500 cc engine. The measurements of the emission factors of CO, HC and NOx gases will be considered in a route established in the city of Quito from 2399 to 2870 meters above sea level. The interaction of the element is carried out in the ANSYS Academic program which is 14977 nodes and 7523 elements to be studied with automatic meshing, obtaining that the EcopaÃs and EcopaÃs + Ferox fuels have the highest heat flow with a 5% divergence compared to the Extra fuel + Ferox. There is a significant reduction in pollutant emissions of 3% of CO with the use of EcopaÃs in comparison to Extra + Ferox fuel, in the case of HC, EcopaÃs and EcopaÃs + Ferox fuels with 3% lower emissions compared to Extra fuel + Ferox, and in NOx, fuels that have Extra + Ferox and EcopaÃs + Ferox solid additives are 3 and 3.5% lower compared to EcopaÃs fuel, respectively.
Keywords: biofuel, termal, on board, ferox, emission factors.
Resumen
El presente trabajo tiene como objetivo fundamental la utilización de un biocombustible (EcopaÃs) en un vehÃculo de inyección directa, es una opción para disminuir daños a la salud y al medio ambiente, para ello se hará una simulación térmica estática en la bujÃa de encendido, para comparar los resultados del mencionado software mediante pruebas On Board, en un motor de 1500 cc. Las mediciones de los factores de emisión de gases de CO, HC y NOx, se contemplará en una ruta establecida en la ciudad de Quito de 2399 hasta 2870 m.s.n.m. La interacción del elemento se realiza en el programa ANSYS Academic que es de 14977 nodos y 7523 elementos a estudiar con el mallado automático, obteniendo que los combustibles EcopaÃs y EcopaÃs+Ferox tienen el mayor flujo de calor con una divergencia del 5% en comparación del combustible Extra + Ferox. Se evidencia una reducción significativa de emisiones contaminantes del 2.5% del CO con el uso del EcopaÃs en comparación del combustible Extra + Ferox, en el caso de HC los combustibles EcopaÃs y EcopaÃs + Ferox con un 1% menor en emisiones en comparación al combustible Extra + Ferox, y en el NOx los combustibles que tienen aditivo sólido Extra+Ferox y EcopaÃs+Ferox son menores en un 6 y 4% con respecto al combustible EcopaÃs respectivamente.
Palabras clave: biocombustible, térmica, on board, ferox, factores de emisiones
Bent it like frs: Extended radio agn in the cosmos field and their large-scale environment
A fascinating topic in radio astronomy is how to associate the complexity of observed radio structures with their environment in order to understand their interplay and the reason for the plethora of radio structures found in surveys. In this project, we explore the distortion of the radio structure of Fanaroff–Riley (FR)-type radio sources in the VLA-COSMOS Large Project at 3 GHz and relate it to their large-scale environment. We quantify the distortion by using the angle formed between the jets/lobes of two-sided FRs, namely bent angle (BA). Our sample includes 108 objects in the redshift range 0.08 < z < 3, which we cross-correlate to a wide range of large-scale environments (X-ray galaxy groups, density fields, and cosmic web probes) in the COSMOS field. The median BA of FRs in COSMOS at zmed∼0.9 is 167.5 +11.5/−37.5 degrees. We do not find significant correlations between BA and large-scale environments within COSMOS covering scales from a few kpc to several hundred Mpc, nor between BA and host properties. Finally, we compare our observational data to magnetohydrodynamical (MHD) adaptive-mesh simulations ENZO-MHD of two FR sources at z = 0.5 and at z = 1. Although the scatter in BA of the observed data is large, we see an agreement between observations and simulations in the bent angles of FRs, following a mild redshift evolution with BA. We conclude that, for a given object, the dominant mechanism affecting the radio structures of FRs could be the evolution of the ambient medium, where higher densities of the intergalactic medium at lower redshifts as probed by our study allow more space for jet interactions
High Resolution, Wide Field, Narrow Band, Snapshot Imaging
We investigate the imaging performance of an interferometric array in the
case of wide field, high resolution, narrow band, snapshot imaging. We find
that, when uv-cell sizes are sufficiently small (ie. image sizes are
sufficiently large), each instantaneous visibility record is gridded into its
own uv-cell. This holds even for dense arrays, like the core of the next
generation VLA. In this particular, application, Uniform weighting of the
gridded visibilities approaches Natural weighting, with its often deleterious
consequences on the resulting synthesized beam. For a core-dominated array, we
show that the resulting image noise is highly correlated on scales comparable
to the spatial frequencies of the core baselines. In general, this study
accentuates the fact that, for imaging applications that require high
resolution (Plains array and greater), many of the core antennas can be
employed as a separate subarray for low resolution science, without sacrificing
the quality of the high resolution science.Comment: 18 pages; Next Generation VLA Memo No. 78;
https://ngvla.nrao.edu/page/memos#gen-mem
Automated mining of the ALMA archive in the COSMOS field (A3COSMOS): I. Robust ALMA continuum photometry catalogs and stellar mass and star formation properties for ∼700 galaxies at z = 0.5–6
The rich information on (sub)millimeter dust continuum emission from distant galaxies in the public Atacama Large Millimeter/submillimeter Array (ALMA) archive is contained in thousands of inhomogeneous observations from individual PI-led programs. To increase the usability of these data for studies deepening our understanding of galaxy evolution, we have developed automated mining pipelines for the ALMA archive in the COSMOS field (A3COSMOS) which efficiently exploit the available information for large numbers of galaxies across cosmic time, and keep the data products in sync with the increasing public ALMA archive: (a) a dedicated ALMA continuum imaging pipeline; (b) two complementary photometry pipelines for both blind source extraction and prior source fitting; (c) a counterpart association pipeline utilizing the multi-wavelength data available (including quality assessment based on machine-learning techniques); (d) an assessment of potential (sub-)mm line
contribution to the measured ALMA continuum; and (e) extensive simulations to provide statistical corrections to biases and uncertainties in the ALMA continuum measurements. Application of these tools yields photometry catalogs with ∼ 1000 (sub-)mm detections (spurious fraction ∼ 8 − 12%) from over 1500 individual ALMA continuum images. Combined with ancillary photometric and redshift catalogs and the above quality assessments, we provide robust information on redshift, stellar mass and star formation rate for ∼700 galaxies at redshifts 0.5-6 in the COSMOS field (with undetermined selection function). The ALMA photometric measurements and galaxy properties are released publicly within our blind-extraction, prior-fitting and galaxy property catalogs, plus the images. These products will be updated on a regular basis in the future
The Role of TLR4 in the Paclitaxel Effects on Neuronal Growth In Vitro
Paclitaxel (Pac) is an antitumor agent that is widely used for treatment of solid cancers. While being effective as a chemotherapeutic agent, Pac in high doses is neurotoxic, specifically targeting sensory innervations. In view of these toxic effects associated with conventional chemotherapy, decreasing the dose of Pac has been recently suggested as an alternative approach, which might limit neurotoxicity and immunosuppression. However, it remains unclear if low doses of Pac retain its neurotoxic properties or might exhibit unusual effects on neuronal cells. The goal of this study was to analyze the concentration-dependent effect of Pac on isolated and cultured DRG neuronal cells from wild-type and TLR4 knockout mice. Three different morphological parameters were analyzed: the number of neurons which developed neurites, the number of neurites per cell and the total length of neurites per cell. Our data demonstrate that low concentrations of Pac (0.1 nM and 0.5 nM) do not influence the neuronal growth in cultures in both wild type and TLR4 knockout mice. Higher concentrations of Pac (1-100 nM) had a significant effect on DRG neurons from wild type mice, affecting the number of neurons which developed neurites, number of neurites per cell, and the length of neurites. In DRG from TLR4 knockout mice high concentrations of Pac showed a similar effect on the number of neurons which developed neurites and the length of neurites. At the same time, the number of neurites per cell, indicating the process of growth cone initiation, was not affected by high concentrations of Pac. Thus, our data showed that Pac in high concentrations has a significant damaging effect on axonal growth and that this effect is partially mediated through TLR4 pathways. Low doses of Pac are devoid of neuronal toxicity and thus can be safely used in a chemomodulation mode. © 2013 Ustinova et al
Literature-based discovery of diabetes- and ROS-related targets
Abstract Background Reactive oxygen species (ROS) are known mediators of cellular damage in multiple diseases including diabetic complications. Despite its importance, no comprehensive database is currently available for the genes associated with ROS. Methods We present ROS- and diabetes-related targets (genes/proteins) collected from the biomedical literature through a text mining technology. A web-based literature mining tool, SciMiner, was applied to 1,154 biomedical papers indexed with diabetes and ROS by PubMed to identify relevant targets. Over-represented targets in the ROS-diabetes literature were obtained through comparisons against randomly selected literature. The expression levels of nine genes, selected from the top ranked ROS-diabetes set, were measured in the dorsal root ganglia (DRG) of diabetic and non-diabetic DBA/2J mice in order to evaluate the biological relevance of literature-derived targets in the pathogenesis of diabetic neuropathy. Results SciMiner identified 1,026 ROS- and diabetes-related targets from the 1,154 biomedical papers (http://jdrf.neurology.med.umich.edu/ROSDiabetes/). Fifty-three targets were significantly over-represented in the ROS-diabetes literature compared to randomly selected literature. These over-represented targets included well-known members of the oxidative stress response including catalase, the NADPH oxidase family, and the superoxide dismutase family of proteins. Eight of the nine selected genes exhibited significant differential expression between diabetic and non-diabetic mice. For six genes, the direction of expression change in diabetes paralleled enhanced oxidative stress in the DRG. Conclusions Literature mining compiled ROS-diabetes related targets from the biomedical literature and led us to evaluate the biological relevance of selected targets in the pathogenesis of diabetic neuropathy.http://deepblue.lib.umich.edu/bitstream/2027.42/78315/1/1755-8794-3-49.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/2/1755-8794-3-49-S7.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/3/1755-8794-3-49-S10.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/4/1755-8794-3-49-S8.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/5/1755-8794-3-49-S3.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/6/1755-8794-3-49-S1.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/7/1755-8794-3-49-S4.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/8/1755-8794-3-49-S2.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/9/1755-8794-3-49-S12.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/10/1755-8794-3-49-S11.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/11/1755-8794-3-49-S9.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/12/1755-8794-3-49-S5.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/13/1755-8794-3-49-S6.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/14/1755-8794-3-49.pdfPeer Reviewe
A3COSMOS: the dust attenuation of star-forming galaxies at z=2.5-4.0 from the COSMOS-ALMA archive
We present an analysis of the dust attenuation of star-forming galaxies at z = 2.5-4.0 through the relationship between the UV spectral slope (β), stellar mass (M*), and the infrared excess (IRX = LIR/LUV) based on far-infrared continuum observations from the Atacama Large Millimeter/sub-millimeter Array (ALMA). Our study exploits the full ALMA archive over the COSMOS field processed by the A3COSMOS team, which includes an unprecedented sample of ∼1500 galaxies at z ∼ 3 as primary or secondary targets in ALMA band 6 or 7 observations with a median continuum sensitivity of 126 μJybeam−1 (1σ). The detection rate is highly mass dependent, decreasing drastically below log (M*/M⊙) = 10.5. The detected galaxies show that the IRX-β relationship of massive (log M*/M⊙ > 10) main-sequence galaxies at z = 2.5-4.0 is consistent with that of local galaxies, while starbursts are generally offset by ∼0.5dex to larger IRX values. At the low-mass end, we derive upper limits on the infrared luminosities through stacking of the ALMA data. The combined IRX-M* relation at log(M∗/M⊙)>9 exhibits a significantly steeper slope than reported in previous studies at similar redshifts, implying little dust obscuration at log M*/M⊙ < 10. However, our results are consistent with earlier measurements at z ∼ 5.5, indicating a potential redshift evolution between z ∼ 2 and z ∼ 6. Deeper observations targeting low-mass galaxies will be required to confirm this finding.PL, DL, and ES acknowledge funding from
the European Research Council (ERC) under the European Union’s
Horizon 2020 research and innovation programme (grant agreement
no. 694343). SL acknowledge funding from SCHI 536/9-1. EFJA
acknowledge support of the Collaborative Research Center 956,
subproject A1, funded by the Deutsche Forschungsgemeinschaft
(DFG)
Contribution of microscopy for understanding the mechanism of action against trypanosomatids
Transmission electron microscopy (TEM) has proved to be a useful tool to study the ultrastructural alterations and the target organelles of new antitrypanosomatid drugs. Thus, it has been observed that sesquiterpene lactones induce diverse ultrastructural alterations in both T. cruzi and Leishmania spp., such as cytoplasmic vacuolization, appearance of multilamellar structures, condensation of nuclear DNA, and, in some cases, an important accumulation of lipid vacuoles. This accumulation could be related to apoptotic events. Some of the sesquiterpene lactones (e.g., psilostachyin) have also been demonstrated to cause an intense mitochondrial swelling accompanied by a visible kinetoplast deformation as well as the appearance of multivesicular bodies. This mitochondrial swelling could be related to the generation of oxidative stress and associated to alterations in the ergosterol metabolism. The appearance of multilamellar structures and multiple kinetoplasts and flagella induced by the sesquiterpene lactone psilostachyin C indicates that this compound would act at the parasite cell cycle level, in an intermediate stage between kinetoplast segregation and nuclear division. In turn, the diterpene lactone icetexane has proved to induce the external membrane budding on T. cruzi together with an apparent disorganization of the pericellar cytoskeleton. Thus, ultrastructural TEM studies allow elucidating the possible mechanisms and the subsequent identification of molecular targets for the action of natural compounds on trypanosomatids.Fil: Lozano, Esteban Sebastián. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Mendoza. Instituto de Medicina y BiologÃa Experimental de Cuyo; ArgentinaFil: Spina Zapata, Renata MarÃa. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Mendoza. Instituto de HistologÃa y EmbriologÃa de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de HistologÃa y EmbriologÃa de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Barrera, Patricia Andrea. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Mendoza. Instituto de HistologÃa y EmbriologÃa de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de HistologÃa y EmbriologÃa de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Tonn, Carlos Eugenio. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - San Luis. Instituto de Investigaciones en TecnologÃa QuÃmica. Universidad Nacional de San Luis. Facultad de QuÃmica, BioquÃmica y Farmacia. Instituto de Investigaciones en TecnologÃa QuÃmica; ArgentinaFil: Sosa Escudero, Miguel Angel. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Mendoza. Instituto de HistologÃa y EmbriologÃa de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de HistologÃa y EmbriologÃa de Mendoza Dr. Mario H. Burgos; Argentin
Safety of two different doses of simvastatin plus rifaximin in decompensated cirrhosis (LIVERHOPE-SAFETY): a randomised, double-blind, placebo-controlled, phase 2 trial
BACKGROUND: Statins have beneficial effects on intrahepatic circulation and decrease portal hypertension and rifaximin modulates the gut microbiome and might prevent bacterial translocation in patients with cirrhosis. Therefore, this drug combination might be of therapeutic benefit in patients with decompensated cirrhosis. However, there is concern regarding the safety of statins in patients with decompensated cirrhosis. We assessed the safety of two different doses of simvastatin, in combination with rifaximin, in patients with decompensated cirrhosis. // METHODS: We did a double-blind, randomised, placebo-controlled, phase 2 trial in patients with decompensated cirrhosis and moderate-to-severe liver failure from nine university hospitals in six European countries (Italy, France, Holland, Germany, the UK, and Spain). Patients older than 18 years with Child-Pugh class B or C disease were eligible. We randomly assigned patients (1:1:1) to receive either simvastatin 40 mg/day plus rifaximin 1200 mg/day, simvastatin 20 mg/day plus rifaximin 1200 mg/day, or placebo of both medications for 12 weeks. Randomisation was stratified according to Child-Pugh class (B vs C) and restricted using blocks of multiples of three. The primary endpoint was development of liver or muscle toxicity, as defined by changes in liver aminotransferases (aspartate aminotransferase [AST] and alanine aminotransferase [ALT]), alkaline phosphastase, and creatine kinase. The study is registered with the European Union Clinical Trials Register, 2016-004499-23, and with ClinicalTrials.gov, NCT03150459. // FINDINGS: The study recruitment period was between July 28, 2017, and Jan 2, 2018. Follow-up finished on March 12, 2018. 50 patients were randomly assigned to simvastatin 40 mg/day plus rifaximin 1200 mg/day (n=18), simvastatin 20 mg/day plus rifaximin 1200 mg/day (n=16), or placebo of both medications (n=16). Six patients (two from each group) were excluded. Therefore, the full analysis set included 44 patients (16 in the simvastatin 40 mg/day plus rifaximin 1200 mg/day group, 14 in the simvastatin 20 mg/day plus rifaximin mg/day group, and 14 in the placebo group). After a safety analyses when the first ten patients completed treatment, treatment was stopped prematurely in the simvastatin 40 mg/day plus rifaximin group due to recommendations by the data safety monitoring board. Patients in the simvastatin 40 mg/day plus rifaximin group showed a significant increase in AST and ALT compared with the placebo group (mean differences between the groups at the end of treatment for AST 130 IU/L [95% CI 54 to 205; p=0·0009] and for ALT 61 IU/L [22 to 100; p=0·0025]. We observed no significant differences at 12 weeks in AST and ALT between the simvastatin 20 mg/day plus rifaximin and placebo group (for AST -14 IU/L [-91 to 64; p=0·728] and for ALT -8 IU/L [-49 to 33; p=0·698]). We observed no significant differences in alkaline phosphatase between the the simvastatin 40 mg/day plus rifaximin or the simvastatin 20 mg/day plus rifaximin groups compared with placebo. Patients in the simvastatin 40 mg/day plus rifaximin group showed an increase in creatine kinase at the end of treatment compared with patients in the placebo group (1009 IU/L [208 to 1809]; p=0·014). We observed no significant changes in creatine kinase in the simvastatin 20 mg/day plus rifaximin group (4·2 IU/L [-804 to 813]; p=0·992). Three (19%) patients in the simvastatin 40 mg/day group developed liver and muscle toxicity consistent with rhabdomyolysis. The number of patients who stopped treatment because of adverse events was significantly higher in the simvastatin 40 mg/day plus rifaximin group (nine [56%] of 16 patients) compared with the other two groups (two [14%] of 14 for both groups; p=0·017). There were no serious unexpected adverse reactions reported during the study. // INTERPRETATION: Treatment with simvastatin 40 mg/day plus rifaximin in patients with decompensated cirrhosis was associated with a significant increase in adverse events requiring treatment withdrawal, particularly rhabdomyolysis, compared with simvastatin 20 mg/day plus rifaximin. We recommend simvastatin 20 mg/day as the dose to be used in studies investigating the role of statins in patients with decompensated cirrhosis. //FUNDING: Horizon 20/20 European programme
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Effect of replacing soybean meal (Glycine max) with sesame meal (Sesamum indicum) on productive traits, carcass characteristics, and gross profit margin in fattening lamb's diets.
The objective of this study was to determine the effect of replacing soybean meal (Glycine max) with sesame meal (Sesamum indicum) on productive traits, carcass characteristics, and gross profit margin (GMP) in fattening lamb's diets. For this, 42 Katahdin lambs were divided into three treatments in duplicate: basal diet + soybean meal (100S), basal diet + sesame meal/soybean meal (50/50SA), and basal diet + sesame meal (100A). Dry matter intake, daily weight gain (DWG), total kg gained (KgT), feed conversion (FC), and feed efficiency (FE) were evaluated; upon reaching the weight for sale, the animals were slaughtered, and hot carcass weight (HCW) was evaluated. The results were analyzed with a completely randomized design with repeated measures. Regarding time, no differences were found between treatments, for DWG (0.171 ± 0.006 kg/d), FC (6.7 ± 0.55), FE (0.175 ± 0.02), KgT (2.86 ± 0.13 kg), HCW (50.97 ± 0.79 kg), as well as for chest depth (26.96 ± 0.33 cm), leg width (20.63 ± 0.028 cm), leg diameter (60.7 ± 0.44 cm), and ribs width (24.05 ± 0.14 cm). GPM was 16.50%, 18.63%, and 19.97% for 100S, 50/50SA, and 100A, respectively. Overall, in fatting lamb diets, replacing soybean meal with sesame meal by either 50% or 100% substitution could be a feasible feeding strategy as in both cases, gross profit was increased, and no negative effects were found for productive traits and carcass quality
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