Bismuth silicate Bi sub(4)Si sub(3)O sub(12) or BSO thin films were synthesized by pulsed laser deposition and a subsequent annealing treatment from a Bi-Fe-O and compared with films obtained with a ...pure Bi sub(2)O sub(3) target. Bi-Fe-O amorphous thin films of different thicknesses were deposited on silicon substrates at room temperature and subsequently heat treated at 800 degree C at different times to study the phase transformations, keeping in all steps a constant oxygen atmosphere. After annealing, Bi-Si-O crystalline phases are formed in all cases with different synthesis kinetics. The Bi-Fe-O target clearly increases the synthesis kinetic of a textured BSO phase having a dissociation and precipitation of homogeneously distributed Fe sub(2)O sub(3) particles in the BSO matrix. The key aspects to obtain the Bi sub(4)Si sub(3)O sub(12) stoichiometric phase are both the film thickness and the heat treatment time to allow the reaction between the Bi sub(2)O sub(3) from the target and the SiO sub(2) obtained after the oxidation of the substrate. A deposition time of Bi-Fe-O for 120 and 30 min annealing fulfills the conditions to obtain the Bi sub(4)Si sub(3)O sub(12) stoichiometric composition and thus scintillation performance. The scintillation properties were measured by a fluorescence spectrophotometry. The stoichiometric Bi sub(4)Si sub(3)O sub(12) samples show that under 260 nm excitation the material exhibits a peak emission at 466.6 nm. These Bi sub(4)Si sub(3)O sub(12) thin films crystallize in eulytite phase with cubic structure (a = b = c = 10.291 Aa). The phase content was obtained by Rietveld analysis of X-ray diffraction patterns.
Environmental and genetic factors may modify or contribute to the phenotypic differences observed in multigenic and monogenic diseases, such as cystic fibrosis (CF). An analysis of modifier genes can ...be helpful for estimating patient prognosis and directing preventive care. The aim of this study is to determine the association between seven genetic variants of four modifier genes and CF by comparing their corresponding allelic and genotypic frequencies in CF patients (n = 81) and control subjects (n = 104). Genetic variants of MBL2 exon 1 (A, B, C and D), the IL-8 promoter (-251 A/T), the TNFalpha promoter (TNF1/TNF2), and SERPINA1 (PI*Z and PI*S) were tested in CF patients and control subjects from northeastern Mexico by PCR-RFLP. Results The TNF2 allele (P = 0.012, OR 3.43, 95% CI 1.25-9.38) was significantly associated with CF under the dominant and additive models but was not associated with CF under the recessive model. This association remained statistically significant after adjusting for multiple tests using the Bonferroni correction (P = 0.0482). The other tested variants and genotypes did not show any association with the disease. Conclusion An analysis of seven genetic variants of four modifier genes showed that one variant, the TNF2 allele, appears to be significantly associated with CF in Mexican patients.
En el 2012 la Organización Mundial de la Salud (OMS) clasificó la radiación ultravioleta (ultraviolet radiation, UVR) como carcinógeno del grupo 1, ello porque existen pruebas suficientes para ...considerarla causa de cáncer en el ser humano. Presentamos aquí los resultados de nuestro estudio sobre la UVR en la zona Centro Occidente de México y su asociación con el riesgo de cáncer de piel, así como la propuesta de una solución tecnológica que contribuya a la difusión de este problema y ofrezca recomendaciones para su prevención. Con este objetivo, se midió y se clasificó la radiación solar ultravioleta durante un año para, posteriormente, investigar y analizar el incremento de cáncer de piel asociado a la UVR. Los resultados fueron los siguientes: a) la presencia de niveles “muy altos” de radiación ultravioleta según el índice de UVR, con un promedio anual en el 2022 de 9,0, y de 10,7 en el cuatrimestre con mayor radiación; b) la causa de uno de cada tres casos de melanoma (un tipo de cáncer de piel) en México es la exposición a la UVR; c) las fuentes secundarias evidenciaron un incremento en los casos de melanoma en México, y d) la propuesta y desarrollo de una App para la divulgación, prevención y reducción del riesgo. El trabajo se ajustó a los Objetivos de Desarrollo Sostenible 3.4 y 3.d planteados en la Agenda 2030 de la Organización de las Naciones Unidas (ONU).
Structural evolution during the synthesis of B2–NiAl intermetallic compound by mechanical alloying of equiatomic elemental mixtures was studied by Rietveld analysis, DSC and HTXRD. The lattice ...parameter, crystallite size, microstrain, amount of phase and ordering of the B2 phase were monitored as a function of milling time. Formation of the B2–NiAl phase shows a sigmoidal behavior, which suggests that Johnson–Mehl–Avrami nucleation and interface-controlled growth are the responsible mechanisms in the transformation. Almost complete transformation (~ 97 mol%) was obtained after 25 h of milling. A specific phase transformation sequence during milling was not absolutely determined, however, the sequence Ni + Al → NiAl
3
→ Ni
2
Al
3
→ B2–NiAl was identified by HTXRD. This sequence was confirmed by DSC. The transformation temperature of the B2–NiAl phase and the presence of additional intermetallic compounds show a direct dependence on the Ni–Al layer spacing. Using a production-scale Simoloyer horizontal Attritor Mill, the presence of Ni
2
Al
3
phase was observed prior to the full synthesis of B2-NiAl.
Introduction: Adenovirus 36 (Ad-36) is associated with the development of overweight and obesity in humans. Most of the research on Ad-36 focuses on the process by which the accumulation of lipids in ...adipocytes is favored, but there are very few studies aimed at evaluating the effect of the virus on dietary intake. Objective: To determine the association of Ad-36 on food consumption in healthy and overweight subjects. Methods: A cross-sectional study included 174 subjects that were recruited from the medical school and nutrition clinics of the Centro Universitario del SUR (CUSUR) in Western Mexico, all of whom answered the semi-quantitative food frequency questionnaire (SFFQ) to assess their eating habits. Their body mass index (BMI) was determined and a blood sample was taken to identify Ad-36, using the ELISA technique. Finally, the participants were classified according to their BMI and the presence of Ad-36, the statistical analysis was performed whit t-test or U-test. Results: Of the 174 subjects included, 52.3% had a BMI ≥25 kg/m2 and 47.7% had a BMI <25 kg/m2. Additionally, 17.2% of the population was positive for Ad-36 antibodies (Ad-36 +), whereas 82.8% was negative for Ad-36 (Ad-36 -). When the study groups were compared, the Ad-36(+) subjects were found to have a higher BMI than the Ad-36(-) individuals (28.13 kg/m2 vs 25.7 kg/m2, p= 0.014). There was an increase in the consumption of kilocalories (2861.66 kcal vs 2182.40 kcal, p 0.018) and lipids (95.33g vs 73.67g, p: 0.002) in individuals with a BMI <25 kg/m2 Ad-36(+), as well. However, in subjects with a BMI ≥25 kg/m2 there were no significant differences in their food intake. Conclusions: The presence of Ad-36 was associated with an increase in caloric intake and lipid intake in subjects with a BMI <25 kg/m2, but not in the group with a BMI ≥25 kg/m2.
We present $\gamma$-ray optical-depth calculations from a recently published
extragalactic background light (EBL) model built from multiwavelength galaxy
data from the Hubble Space Telescope Cosmic ...Assembly Near-Infrared Deep
Extragalactic Legacy Survey (HST/CANDELS). CANDELS gathers one of the deepest
and most complete observations of stellar and dust emissions in galaxies. This
model resulted in a robust derivation of the evolving EBL spectral energy
distribution up to $z\sim 6$, including the far-infrared peak. Therefore, the
optical depths derived from this model will be useful for determining the
attenuation of $\gamma$-ray photons coming from high-redshift sources, such as
those detected by the Large Area Telescope on board the Fermi Gamma-ray Space
Telescope, and for multi-TeV photons that will be detected from nearby sources
by the future Cherenkov Telescope Array. From these newly calculated optical
depths, we derive the cosmic $\gamma$-ray horizon and also measure the
expansion rate and matter content of the Universe including an assessment of
the impact of the EBL uncertainties. We find $H_{0}=61.9$ $^{+2.9}_{-2.4}$ km
s$^{-1}$ Mpc$^{-1}$ when fixing $\Omega_{m}=0.32$, and $H_{0}=65.6$
$^{+5.6}_{-5.0}$ km s$^{-1}$ Mpc$^{-1}$ and $\Omega_{m}=0.19\pm 0.07$, when
exploring these two parameters simultaneously.
Finding reliable indicators of Lyman continuum (LyC) photon leakage from galaxies is essential in order to infer their escape fraction in the epoch of reionisation, where direct measurements of LyC ...flux are impossible. To this end, here we investigate whether strong C IV \(\lambda \lambda 1548,1550\) emission in the rest-frame UV spectra of galaxies traces conditions ripe for ample production and escape of LyC photons. We compile a sample of 19 star-forming galaxies in the redshift range \(z=3.1-4.6\) from the VANDELS survey that exhibit strong C IV emission, producing a stacked spectrum where all major rest-UV emission lines are clearly detected. Best-fitting spectral energy distribution models containing both stellar and nebular emission suggest the need for low stellar metallicities (\(Z=0.1-0.2\,Z_\odot\)), young stellar ages (\(\log(\rm{age/yr}) = 6.1-6.5\)), a high ionisation parameter (\(\log U = -2\)) and little to no dust attenuation (\(E(B-V)=0.00-0.01\)). However, these models are unable to fully reproduce the observed C IV and He II line strengths. We find that the Ly\(\alpha\) line in the stacked spectrum is strong and peaks close to the systemic velocity, features that are indicative of significant LyC photon leakage along the line-of-sight. The covering fractions of low-ionisation interstellar absorption lines are also low implying LyC escape fraction in the range \(\approx 0.05-0.30\), with signatures of outflowing gas. Finally, C IV/C III ratios of >0.75 for a subset of individual galaxies with reliable detections of both lines are also consistent with physical conditions that enable significant LyC leakage. Overall, we report that multiple spectroscopic indicators of LyC leakage are present in the stacked spectrum of strong C IV emitting galaxies, potentially making C IV an important tracer of LyC photon escape at \(z>6\).
Mostramos las frecuencias Raman del biomarcador N-óxido de trimetilamina (TMAO), con el objetivo de comparar el espectro experimental de la sustancia pura y el obtenido mediante software de química ...cuántica computacional GAUSSIAN ®, a partir de las optimizaciones con mecanismos moleculares Universal Force Field (UFF) y Merck Molecular Force Field 94 (MMFF94), en combinación con las funcionales de Hartree Fock (HF) y la Teoría Funcional de la Densidad (TFD), siendo Becke Lee Yang Parr (B3LYP) el principal funcional híbrido para la obtención de frecuencias Raman aproximadas a los resultados experimentales. Relevancia Clínica- El TMAO es un osmolito que se puede sintetizar a partir de varios precursores, la cantidad presente en el organismo depende de la dieta y la micro flora intestinal. En recientes años se ha identificado que la presencia de altas concentraciones del biomarcador en tejidos biológicos se asocia con diversas enfermedades crónico degenerativas, como hipertensión, síndrome metabólico, diabetes tipo II y eventos cardiovasculares graves. 1
Here we present high spectral resolution \(\textit{JWST}\) NIRSpec observations of GN42437, a low-mass (log(M\(_\ast/M_\odot)=7.9\)), compact (\(r_e < 500\)pc), extreme starburst galaxy at \(z=5.59\) ...with 13 emission line detections. GN42437 has a low-metallicity (5-10% Z\(_\odot\)) and its rest-frame H\(\alpha\) equivalent width suggests nearly all of the observed stellar mass formed within the last 3 Myr. GN42437 has an extraordinary 7\(\sigma\) significant Ne V 3427 \(\mathring{\rm A}\) detection. The Ne V line has a rest-frame equivalent width of \(11\pm2\mathring{\rm A}\), Ne V/H\(\alpha =0.04\pm0.007\), Ne V/Ne III 3870\(\mathring{\rm A} = 0.26\pm0.04\), and Ne V/He II 4687 \(\mathring{\rm A} = 1.2\pm0.5\). Ionization from massive stars, shocks, or high-mass X-ray binaries cannot simultaneously produce these Ne V and low-ionization line ratios. Reproducing the complete nebular structure requires both massive stars and accretion onto a black hole. We do not detect broad lines nor do the traditional diagnostics indicate that GN42437 has an accreting black hole. Thus, the very-high-ionization emission lines powerfully diagnose faint narrow-line black holes at high-redshift. We approximate the black hole mass in a variety of ways as log(M\(_{\rm BH}/M_\odot) \sim 5-7\). This black hole mass is consistent with local relations between the black hole mass and the observed velocity dispersion, but significantly more massive than the stellar mass would predict. Very-high-ionization emission lines may reveal samples to probe the formation and growth of the first black holes in the universe.
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