RESUMEN

The magnetic properties of disordered Nd0.5Ba0.5Mn0.5Fe0.5O3-δ/2 and ordered NdBaMnFeO6-δ perovskites were investigated through temperature- and field-dependent DC-magnetization measurements. The temperature dependence of magnetic susceptibilities revealed that antiferromagnetic ordering occurs at temperatures below 185 K for the disordered Nd0.5Ba0.5Mn0.5Fe0.5O3-δ/2 sample, whereas the ordered NdBaMnFeO6-δ perovskite exhibited a paramagnetic state throughout the entire temperature range examined. Notably, the disordered sample exhibited a glassy state, even at room temperature, which transformed into an antiferromagnetic state under higher applied magnetic fields. The magnetic ordering in the disordered Nd0.5Ba0.5Mn0.5Fe0.5O3-δ/2 perovskite and the magnetic-disordering state in the structurally ordered NdBaMnFeO6-δ perovskite could be attributed to the alteration of the oxidation state of Mn.

RESUMEN

In the presented work, a study on the solubility and intermolecular interactions of l-serine and L-cysteine was carried out in binary mixtures of H2O + dimethylformamide (DMF), H2O + dimethylsulfoxide (DMSO), and H2O + acetonitrile (ACN) in the temperature range of T = 288.15 K to 308.15 K. l-serine exhibited the highest solubility in water, while L-cysteine was more soluble in water-DMF. The solvation process was assessed through standard Gibbs energy calculations, indicating the solvation stability order: water-ACN > water-DMSO > water-DMF for l-serine, and water-DMF > water-DMSO > water-ACN for L-cysteine. This study also explored the influence of these amino acids on solvent-solvent interactions, revealing changes in chemical entropies and self-association patterns within the binary solvent mixtures.

Asunto(s)

RESUMEN

In this work, density functional theory (DFT)-based calculations were performed to compute the physical properties (structural stability, mechanical behavior, and electronic, thermodynamic, and optical properties) of synthesized MAX phases Hf2SB, Hf2SC, Hf2SeB, Hf2SeC, and Hf2TeB and the as-yet-undiscovered MAX carbide phase Hf2TeC. Calculations of formation energy, phonon dispersion curves, and elastic constants confirmed the stability of the aforementioned compounds, including the predicted Hf2TeC. The obtained values of lattice parameters, elastic constants, and elastic moduli of Hf2SB, Hf2SC, Hf2SeB, Hf2SeC, and Hf2TeB showed fair agreement with earlier studies, whereas the values of the aforementioned parameters for the predicted Hf2TeC exhibit a good consequence of B replacement by C. The anisotropic mechanical properties are exhibited by the considered MAX phases. The metallic nature and its anisotropic behavior were revealed by the electronic band structure and density of states. The analysis of the thermal properties-Debye temperature, melting temperature, minimum thermal conductivity, and Grüneisen parameter-confirmed that the carbide phases were more suited than the boride phases considered herein. The MAX phase's response to incoming photons further demonstrated that they were metallic. Their suitability for use as coating materials to prevent solar heating was demonstrated by the reflectivity spectra. Additionally, this study demonstrated the impact of B replacing C in the MAX phases.

RESUMEN

The design of water-stable photo and electrocatalysts of metal-organic frameworks (MOFs) for its promising catalytic applications at long-term irradiations or persisted current loads is extremely necessary but still remains as challenging. A limited number of reports on Ti-MOF-based catalysts for water splitting are only available to explain and understand the correlation between the nature of materials and MOFs array. Herein, spherical Ti-MOFs and corresponding partially annealed hollow core-shell Ti-MOFs (Ti-MOF/D) are designed and the correlation with their photo(electro)catalytic water splitting performance is evaluated. The switchable valence state of Ti for the Ti-MOF as a function of molecular bonding is the possible reason behind the observed photocatalytic hydrogen generation and light-harvesting ability of the system. Besides, the defect state, solid core-shell mesoporous structure, and active sites of Ti-MOF help to trap the charge carriers and the reduction of the recombination process. This phenomenon is absent for hollow core-shells Ti-MOF/D spheres due to the rigid TiO2 outer surface although there is a contradiction in surface area with Ti-MOF. Considering the diversity of Ti-MOF and Ti-MOF/D, further novel research can be designed using this way to manipulate their properties as per the requirements.

RESUMEN

In this study we estimated the solubilities of glycine, D,L-alanine, D,L-nor-valine and D,L-serine in aqueous mixtures of potassium sulfate (K2SO4) at 298.15 K using analytical 'gravimetric method'. The experimental solubilities of homologous series of amino acids in aqueous K2SO4 mixture were discussed in terms of relative solubility, salting-in and salting-out effect by evaluating the influential constants. The effect of physicochemical and chemical factors on solubility were discussed briefly and correlated with the thermodynamics. Initially, the study of solvation energetics such as transfer Gibbs energies were evaluated based on the calculations from solubility data and relative stability of the experimental molecules was discussed under the experimental condition.

RESUMEN

BACKGROUND: Urothelial bladder cancer (BLCA) is one of the most common internal malignancies worldwide with poor prognosis. This study aims to explore effective prognostic biomarkers and construct a prognostic risk score model for patients with BLCA. METHODS: Weighted gene co-expression network analysis (WGCNA) was used for identifying the co-expression module related to the pathological stage of BLCA based on the RNA-Seq data retrieved from The Cancer Genome Atlas database. Prognostic biomarkers screened by Cox proportional hazard regression model and random forest were used to construct a risk score model that can predict the prognosis of patients with BLCA. The GSE13507 dataset was used as the independent testing dataset to test the performance of the risk score model in predicting the prognosis of patients with BLCA. RESULTS: WGCNA identified seven co-expression modules, in which the brown module consisted of 77 genes was most significantly correlated with the pathological stage of BLCA. Cox proportional hazard regression model and random forest identified TPST1 and P3H4 as prognostic biomarkers. Elevated TPST1 and P3H4 expressions were associated with the high pathological stage and worse survival. The risk score model based on the expression level of TPST1 and P3H4 outperformed pathological stage indicators and previously proposed prognostic models. CONCLUSION: The gene co-expression network-based study could provide additional insight into the tumorigenesis and progression of BLCA, and our proposed risk score model may aid physicians in the assessment of the prognosis of patients with BLCA.

Asunto(s)

RESUMEN

Sunlight is the most abundant renewable energy resource, providing the earth with enough power that is capable of taking care of all of humanity's desires-a hundred times over. However, as it is at times diffuse and intermittent, it raises issues concerning how best to reap this energy and store it for times when the Sun is not shining. With increasing population in the world and modern economic development, there will be an additional increase in energy demand. Devices that use daylight to separate water into individual chemical elements may well be the answer to this issue, as water splitting produces an ideal fuel. If such devices that generate fuel were to become widely adopted, they must be low in cost, both for supplying and operation. Therefore, it is essential to research for cheap technologies for water ripping. This review summarizes the progress made toward such development, the open challenges existing, and the approaches undertaken to generate carbon-free energy through water splitting.

RESUMEN

To study the leaves of Adiantum philippense L. for their antioxidant, cytotoxicity and thrombolytic activities and to perform phytochemical evaluation. Methods: In-vitro antioxidant activity of extract was studied using DPPH radical scavenging, reducing power, total phenol and total flavonoid content determination assays. The cytotoxic activity was determined using brine shrimp lethality bioassay, thrombolytic activity by clot disruption and phytochemical potential by qualitative analysis. Results: The antioxidant activity of the extracts was found promising. The reducing power of this crude extract increase with the increase of concentration; IC50 values of DPPH scavenging activity was (140.00±0.86) μg/mL as compared to ascorbic acid [IC50 (130.00±0.76) μg/mL];Total phenol and total flavonoids content were (148.26±0.24) mg/mL and (163.06±0.56) mg/mL respectively. In cytotoxicity assay the LC50 values of the sample was (106.41±0.78) μg/mL where as for standard vincristin sulphate was (08.50±0.24) μg/mL as a positive control and the extract shows (12.86±1.02)% clot lytic whereas standard streptokinase shows (30.86±0.44% clot lytic activity in thrombolytic assay. The phytochemical evaluation indicates the presence of chemical constituents including carbohydrates, alkaloids, saponins, glycosides, flavonoids. Conclusions: This study shows that the methanol extract of leaves of Adiantum philippense L. has bioactivity but further compound isolation is necessary to confirm the activities of individual compounds.

RESUMEN

BACKGROUND: This prospective non-randomized clinical study was done to compare Off-pump and On-pump myocardial revascularization by Troponin I release in patients undergoing first elective coronary artery bypass graft used to evaluate myocardial injury. METHODS: One hundred an twenty patients were non-randomly assigned to a Off-pump or On-pump myocardial revascularization group. Cardiac Troponin I (CTnI) were measured in serial venous blood samples drawn preoperatively in both groups. In On-pump group after aortic unclamping at 12 and 24 hours and in Off-pump group after the last distal anastomosis at 12 and 24 hours. RESULTS: The total amount of CTnI release were significantly higher in On-pump group than in Off-pump group. In On-pump group it was 2.1 +/- 1.9 (mean +/- SD) ng/ml vs in Off-pump group it was 1.0 +/- 1.7 (mean +/- SD) ng/ml at 12 hours and in On-pump group it was 1.6 +/- 1.6 (mean +/- SD) ng/ml vs. in Off-pump group it was .9 +/- 1.6 (mean +/- SD) ng/ml at 24 hours (P < 0.0001 for the pattern). CONCLUSION: The lower release of CTnI in the Off-pump myocardial revascularization group indicates that the arrested heart coronary revascularization group causes more damage to the heart due to cardiopulmonary bypass than Off-pump myocardial revascularization group.

Asunto(s)

Asunto(s)

RESUMEN

The sub-acute toxicities of two compounds 3,4-dimethoxycinnamyl alcohol (1) and 3,4,5-trimethoxycinnamyl alcohol (2) isolated from the plant Loranthus globosus Roxb were studied on long Evan's rats. The studies included the gross general observation such as changes in body weight, haematological profiles [total count of Red Blood Cells (RBC) and White Blood Cells (WBC), differential count of WBC, platelet count and Haemoglobin (Hb)%], biochemical parameters of blood [Serum Glutamate Oxaloacetate Transaminase (SGOT), Serum Glutamate Pyruvate Transaminase (SGPT), Serum Alkaline Phosphatase (SALP), urea and creatinine) and histopathology of the liver, kidney, heart and lung of both control and experimental groups of rats. The changes in haematological and biochemical parameters were statistically not significant after the administration of compounds 1 and 2 in a dose of 300 microg/rat/day for consecutive 14 days. No abnormality was found in the histopathology of the liver, kidney, heart and lung in the experimental groups of rats following same dose when compared with control group. This preliminary study suggests that the isolated compounds may be used safely for clinical trial.

Asunto(s)

RESUMEN

The aim of this study was to determine therapeutic effects of complete Freund's adjuvant (CFA) on the progression and relapsing of pristine-induced arthritis (PIA) and investigate the mechanism involved. Chronic relapsing arthritis was induced by pristine in LEW rats. After onset of arthritis, rats were intradermally injected CFA and rats in control group were injected the same volume of PBS. Arthritis was monitored visually, and joint pathology was examined histologically. Cytokine mRNA expression in inguinal lymph nodes was assessed by RT-PCR. The levels of nitric oxide (NO) in serum were measured by colorimetric assay. The results showed that CFA significantly suppressed the progression and relapsing of PIA. Relapsing rate of PIA in CFA-treated group was 12.5% and it was 85.7% in PBS-control group (P < 0.005). CFA markedly inhibited the infiltration of inflammatory cells and cartilage damage in the joints of CFA-treated rats and promoted the increases of IFN-y mRNA and NO levels. The present study provided an implication that adjuvant therapy may be a new strategy for the treatments of rheumatoid arthritis (RA) and other chronic inflammatory diseases.

Asunto(s)