16,462 research outputs found
Unitarity of the Leptonic Mixing Matrix
We determine the elements of the leptonic mixing matrix, without assuming
unitarity, combining data from neutrino oscillation experiments and weak
decays. To that end, we first develop a formalism for studying neutrino
oscillations in vacuum and matter when the leptonic mixing matrix is not
unitary. To be conservative, only three light neutrino species are considered,
whose propagation is generically affected by non-unitary effects. Precision
improvements within future facilities are discussed as well.Comment: Standard Model radiative corrections to the invisible Z width
included. Some numerical results modified at the percent level. Updated with
latest bounds on the rare tau decay. Physical conculsions unchange
Thermal Evolution and Stability of Pr2O3-doped ZrO2 Powder and Thin Films
AbstractZrO2 powders and films with 5, 8, 9 and 10mol % of Pr2O3 were prepared by a modified sol-gel method using liquid precursors. The thermal stability of the different phases is crucial in order to use this material in devices such as fuel cells, where the appearance of unwanted spurious phases causes a negative impact in the efficiency of such devices. DTA-TG and HT-XRD analysis carried out on the powders show that crystallization takes place around 500°C. Heat treatments over 1000°C produces destabilization of the initial crystallization cubic phase in the powders as well as in the films. However, aging treatments consisting in thermal cycles between room temperature and 750°C, which is the temperature of technological interest, do not affect the structure, the microstructure and the stresses state of the Pr-doped ZO2 thin films
Physics potential of the ESSνSB
The ESSνSB project proposes to base a neutrino “Super Beam” of unprecedented luminosity at the European Spallation Source. The original proposal identified the second peak of the oscillation probability as the optimal to maximize the discovery potential to leptonic CP violation. However this choice reduces the statistics at the detector and penalizes other complementary searches such as the determination of the atmospheric oscillation parameters, particularly the octant of θ23 as well as the neutrino mass ordering. We explore how these shortcomings can be alleviated by the combination of the beam data with the atmospheric neutrino sample that would also be collected at the detector. We find that the combination not only improves very significantly these drawbacks, but also enhances both the CP violation discovery potential and the precision in the measurement of the CP violating phase, for which the facility was originally optimized, by lifting parametric degeneracies. We then reassess the optimization of the ESSνSB setup when the atmospheric neutrino sample is considered, with an emphasis in performing a measurement of the CP violating phase as precise as possible. We find that for the presently preferred value of δ∼ - π/ 2 , shorter baselines and longer running time in neutrino mode would be optimal. In these conditions, a measurement better than 14º ∘ would be achievable for any value of the θ23 octant and the mass ordering. Conversely, if present and next generation facilities were not able to discover CP violation, longer baselines and more even splitting between neutrino and neutrino modes would be preferable. These choices would allow a 5 σ discovery of CP violation for around a 60 % of the possible values of δ and to determine its value with a precision around 6 ∘ if it is close to 0 or πThis work is supported in part by the European Union’s Horizon 2020 research and innovation programme under the Marie SklodowskaCurie Grant agreements 674896-Elusives, 690575-InvisiblesPlus, and 777419-ESSnuSB, as well as by the COST Action CA15139 EuroNuNet. MB, EFM, and SR acknowledge support from the “Spanish Agencia Estatal de Investigación” (AEI) and the EU “Fondo Europeo de Desarrollo Regional” (FEDER) through the project FPA2016-78645- P; and the Spanish MINECO through the “Ramón y Cajal” programme and through the Centro de Excelencia Severo Ochoa Program under Grant SEV-2016-059
Thermodynamic properties of CO2 + SO2 + CH4 mixtures over wide ranges of temperature and pressure. Evaluation of CO2/SO2 co-capture in presence of CH4 for CCS
In this work, density, vapor-liquid equilibrium and speed of sound measurements of the mixtures [CO2+ 4.72 mol% SO2+ 1.85 mol% CH4] and [CO2+ 0.09 mol% SO2+ 1.54 mol% CH4] were performed over the temperature range 263-373 K and at pressures of up to 30 MPa for density and up to 190 MPa for speed of sound. For the speed of sound measurements, the mixtures were doped with congruent to 0.8 mol% CH3OH. We compared our results to the values calculated using an extended version of the equation of state for combustion gases (EOSCG) that includes binary models for the CO2+ SO2 and CO2+ CH4 subsystems, and a perturbed-chain statistical associating fluid theory (PC-SAFT) equation of state, validating both equations in this way. From our experimental results, we evaluated the impact of the simultaneous presence of SO2 and CH4 as impurities in anthropogenic CO2 on selected parameters for carbon capture and storage technology. With the understanding that chemical effects have not been considered, we concluded that the presence of 4.72 mol% SO2 compensates for the negative effect of 1.85 mol% CH4 on most of the studied parameters, resulting in a favorable fluid for carbon, capture and storage, contrary to the mixture with 0.09 mol% SO2 and 1.54 mol% CH4
Myristic acid potentiates palmitic acid-induced lipotoxicity and steatohepatitis associated with lipodystrophy by sustaning de novo ceramide synthesis.
Palmitic acid (PA) induces hepatocyte apoptosis and fuels de novo ceramide synthesis in the endoplasmic reticulum (ER). Myristic acid (MA), a free fatty acid highly abundant in copra/palmist oils, is a predictor of nonalcoholic steatohepatitis (NASH) and stimulates ceramide synthesis. Here we investigated the synergism between MA and PA in ceramide synthesis, ER stress, lipotoxicity and NASH. Unlike PA, MA is not lipotoxic but potentiated PA-mediated lipoapoptosis, ER stress, caspase-3 activation and cytochrome c release in primary mouse hepatocytes (PMH). Moreover, MA kinetically sustained PA-induced total ceramide content by stimulating dehydroceramide desaturase and switched the ceramide profile from decreased to increased ceramide 14:0/ceramide16:0, without changing medium and long-chain ceramide species. PMH were more sensitive to equimolar ceramide14:0/ceramide16:0 exposure, which mimics the outcome of PA plus MA treatment on ceramide homeostasis, than to either ceramide alone. Treatment with myriocin to inhibit ceramide synthesis and tauroursodeoxycholic acid to prevent ER stress ameliorated PA plus MA induced apoptosis, similar to the protection afforded by the antioxidant BHA, the pan-caspase inhibitor z-VAD-Fmk and JNK inhibition. Moreover, ruthenium red protected PMH against PA and MA-induced cell death. Recapitulating in vitro findings, mice fed a diet enriched in PA plus MA exhibited lipodystrophy, hepatosplenomegaly, increased liver ceramide content and cholesterol levels, ER stress, liver damage, inflammation and fibrosis compared to mice fed diets enriched in PA or MA alone. The deleterious effects of PA plus MA-enriched diet were largely prevented by in vivo myriocin treatment. These findings indicate a causal link between ceramide synthesis and ER stress in lipotoxicity, and imply that the consumption of diets enriched in MA and PA can cause NASH associated with lipodystrophy
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Association between English Proficiency and Kidney Disease Knowledge and Communication Quality among Patients with ESKD
KEY POINTS: In one hospital-based safety-net dialysis unit, only one half of patients with ESKD knew their cause of kidney failure, which did not differ by English proficiency status. Patients with limited English proficiency (versus English-proficient patients) reported poorer communication with the dialysis care team (less listening, fewer clear explanations, less time spent). We highlight the need for tailored, patient-centered communication between limited English-proficient patients and dialysis care team members. BACKGROUND: ESKD is a chronic health condition for which communication between health care teams and patients is important to guide patient self-management activities. Yet, little is known about the quality of communication among patients with ESKD and their care team members. We examined the influence of patient's limited English proficiency (LEP) status on communication experiences at one dialysis center. METHODS: A survey was administered to adults receiving ESKD care at a dialysis unit within a public health care delivery system between July 2022 and February 2023, to ascertain kidney disease knowledge and perceptions of communication quality with the dialysis care team. Multivariable logistic and ordinal logistic regression models adjusted for age and sex were used to determine associations between LEP status and CKD knowledge. RESULTS: Among 93 eligible patients, 88.2% (n=82) completed the survey. Approximately 37.8% (n=31) had LEP, mean age was 58.8 years, 68.3% were men, mean dialysis vintage was 3.9 years, and 25% had a positive depression screen (LEP 30%; English-proficient 22%). A higher proportion of English-proficient patients screened positive for limited health literacy compared to those with LEP (74.5% versus 38.7%, P = 0.002). Overall, knowledge of assigned cause of ESKD (53.4%) and CKD/transplant knowledge (57.3%) was suboptimal. After adjustment, LEP status was not significantly associated with knowing the correct cause of kidney failure (odds ratio, 0.49; 95% confidence interval, 0.19 to 1.27) but was significantly associated with having a higher score on a CKD/transplant knowledge scale (odds ratio, 3.99; 95% confidence interval, 1.66 to 9.58). Patients with LEP reported poorer communication quality with dialysis providers and staff (less listening, fewer clear explanations, less time spent with patients) compared with English-proficient patients, although differences were not statistically significant. CONCLUSIONS: Overall communication between patients with ESKD and members of the dialysis care team was suboptimal, regardless of English proficiency. Interventions to enhance communication for ESKD patients are needed
Recent Technological Developments on LGAD and iLGAD Detectors for Tracking and Timing Applications
This paper reports the last technological development on the Low Gain
Avalanche Detector (LGAD) and introduces a new architecture of these detectors
called inverse-LGAD (iLGAD). Both approaches are based on the standard
Avalanche Photo Diodes (APD) concept, commonly used in optical and X-ray
detection applications, including an internal multiplication of the charge
generated by radiation. The multiplication is inherent to the basic n++-p+-p
structure, where the doping profile of the p+ layer is optimized to achieve
high field and high impact ionization at the junction. The LGAD structures are
optimized for applications such as tracking or timing detectors for high energy
physics experiments or medical applications where time resolution lower than 30
ps is required. Detailed TCAD device simulations together with the electrical
and charge collection measurements are presented through this work.Comment: Keywords: silicon detectors, avalanche multiplication, timing
detectors, tracking detectors. 8 pages. 8 Figure
Mechanisms and kinetics of C-S-H nucleation approaching the spinodal line: Insights into the role of organics additives
Wet chemistry C-S-H precipitation experiments were performed under controlled
conditions of solution supersaturation in the presence and absence of gluconate
and three hexitol molecules. Characterization of the precipitates with SAXS and
cryo-TEM experiments confirmed the presence of a multi-step nucleation pathway.
Induction times for the formation of the amorphous C-S-H spheroids were
determined from light transmittance. Analysis of those data with the classical
nucleation theory revealed a significant increase of the kinetic prefactor in
the same order as the complexation constants of calcium and silicate with each
of the organics. Finally, two distinct precipitation regimes of the C-S-H
amorphous precursor were identified: i) a nucleation regime at low saturation
indexes (SI) and ii) a spinodal nucleation regime at high SI where the free
energy barrier to the phase transition is found to be of the order of the
kinetic energy or less.Comment: Accepted in Cement and Concrete Research. 30 pages plus supplementary
materials. arXiv admin note: substantial text overlap with arXiv:2111.0274
Vaccinia virus replication is not affected by APOBEC3 family members
BACKGROUND: The APOBEC3G protein represents a novel innate defense mechanism against retroviral infection. It facilitates the deamination of the cytosine residues in the single stranded cDNA intermediate during early steps of retroviral infection. Most poxvirus genomes are relatively A/T-rich, which may indicate APOBEC3G-induced mutational pressure. In addition, poxviruses replicate exclusively in the cytoplasm where APOBEC3G is located. It was therefore tempting to analyze whether vaccinia virus replication is affected by APOBEC3G. RESULTS: The replication of vaccinia virus, a prototype poxvirus, was not, however, inhibited in APOBEC3G-expressing cells, nor did other members of the APOBEC3 family alter vaccinia virus replication. HIV counteracts APOBEC3G by inducing its degradation. However, Western blot analysis showed that the levels of APOBEC3G protein were not affected by vaccinia virus infection. CONCLUSION: The data indicate that APOBEC3G is not a restriction factor for vaccinia virus replication nor is vaccinia virus able to degrade APOBEC3G
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