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1.
Chemosphere ; 326: 138436, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36933842

RESUMEN

The renewability and zero carbon emissions of hydrogen make it a promising clean energy resource to meet future energy demands. Owing to its benefits, photocatalytic water-splitting has been extensively investigated for hydrogen production. However, the low efficiency poses a serious challenge to its implementation. Herein, we attempted to synthesize bimetallic transition metal selenides, namely Co/Mo/Se (CMS) photocatalysts, with varying atomic compositions (CMSa, CMSb, and CMSc) and investigated their photocatalytic water splitting efficiencies. The observed hydrogen evolution rates were as follows: 134.88 µmol g-1 min-1 for CoSe2, 145.11 µmol g-1 min-1 for MoSe2, 167.31 µmol g-1 min-1 for CMSa, 195.11 µmol g-1 min-1 for CMSb, and 203.68 µmol g-1 min-1 for CMSc. Hence, we deemed CMSc to be the most potent photocatalytic alternative among the compounds. CMSc was also tested for its efficiency towards degradation of triclosan (TCN), and results substantiated that CMSc succeeded degrading 98% TCN while CMSa and b were able to degrade 80 and 90% TCN respectively-the attained efficiency being exponentially higher than CoSe2 and MoSe2 taken for comparative analysis in addition to complete degradation of the pollutants leaving no harmful intermediaries during the process. Thus, CMSc shall be identified as a highly potential photocatalyst with respect to both environmental and energy applications.


Asunto(s)
Cobalto , Molibdeno , Luz , Agua , Hidrógeno
2.
Chemosphere ; 307(Pt 2): 135937, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35934097

RESUMEN

Hydrogen has been considered as a promising clean energy source owing to its renewability and zero carbon emission. Accordingly, photocatalytic water splitting has drawn much attention as a key green technology of producing hydrogen. However, it has remained as a great challenge due to the low production rate and expensive constituents of photocatalytic systems. Herein, we synthesised nanostructures consisting of transition metal selenide and g-C3N4 for photocatalytic water splitting reaction. They include ZnSe, FeSe2, Zn/FeSe2 and ZnFeSe2 nanoflowers and a nanocomposite made of Zn/FeSe2 and g-C3N4. Hydrogen evolution rates in the presence of ZnSe, FeSe2, Zn/FeSe2 and ZnFeSe2 photocatalysts were measured as 60.03, 128.02, 155.11 and 83.59 µmolg-1 min-1, respectively. On the other hand, with the nanocomposite consisting of Zn/FeSe2 and g-C3N4, the hydrogen and oxygen evolution rates were significantly enhanced up to 202.94 µmol g-1min-1 and 90.92 µmol g-1min-1, respectively. The nanocomposite was also examined as a photocatalyst for degradation of rhodamine B showing that it photodegrades the compound two times faster compared to pristine Zn/FeSe2 nanoflowers without g-C3N4. Our study suggests the nanocomposite of Zn/FeSe2 and g-C3N4 as a promising photocatalyst for energy and environmental applications.


Asunto(s)
Hierro , Agua , Carbono , Hidrógeno/química , Oxígeno , Compuestos de Selenio , Agua/química , Zinc , Compuestos de Zinc
3.
J Korean Med Sci ; 37(26): e205, 2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-35790207

RESUMEN

BACKGROUND: The advancement of information technology has immensely increased the quality and volume of health data. This has led to an increase in observational study, as well as to the threat of privacy invasion. Recently, a distributed research network based on the common data model (CDM) has emerged, enabling collaborative international medical research without sharing patient-level data. Although the CDM database for each institution is built inside a firewall, the risk of re-identification requires management. Hence, this study aims to elucidate the perceptions CDM users have towards CDM and risk management for re-identification. METHODS: The survey, targeted to answer specific in-depth questions on CDM, was conducted from October to November 2020. We targeted well-experienced researchers who actively use CDM. Basic statistics (total number and percent) were computed for all covariates. RESULTS: There were 33 valid respondents. Of these, 43.8% suggested additional anonymization was unnecessary beyond, "minimum cell count" policy, which obscures a cell with a value lower than certain number (usually 5) in shared results to minimize the liability of re-identification due to rare conditions. During extract-transform-load processes, 81.8% of respondents assumed structured data is under control from the risk of re-identification. However, respondents noted that date of birth and death were highly re-identifiable information. The majority of respondents (n = 22, 66.7%) conceded the possibility of identifier-contained unstructured data in the NOTE table. CONCLUSION: Overall, CDM users generally attributed high reliability for privacy protection to the intrinsic nature of CDM. There was little demand for additional de-identification methods. However, unstructured data in the CDM were suspected to have risks. The necessity for a coordinating consortium to define and manage the re-identification risk of CDM was urged.


Asunto(s)
Investigación Biomédica , Estudios Transversales , Bases de Datos Factuales , Humanos , Reproducibilidad de los Resultados
4.
Chemosphere ; 303(Pt 2): 135091, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35644242

RESUMEN

The wide use of antibiotics has caused their continual release and persistence in the eco-system, subsequently giving birth to antibiotic resistant bacterial species in the aquatic environment, thereby necessitating immediate and efficient remediation of the contaminated environment. In the present study, we synthesized Ag/Ag2S@BiOI nanowires with an average diameter of ∼150 nm and length of 3-5 µm using a hydrothermal method and employed them as photocatalysts for photocatalytic degradation of tetracycline as a model antibiotic. The nanowire achieved nearly complete degradation of tetracycline (∼99%) within 60 min at the optimal condition of 100 mg/L TC concentration and pH 2. The degradation followed pseudo-first order kinetics, with a rate constant of 0.06228 min- 1. Our toxicity tests showed that the nanowire has negligible toxicity towards PBMC cells, suggesting it as a promising photocatalyst.


Asunto(s)
Nanocables , Antibacterianos/toxicidad , Catálisis , Femenino , Humanos , Leucocitos Mononucleares , Embarazo , Tetraciclina/toxicidad
5.
Chemosphere ; 301: 134699, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35483659

RESUMEN

Pharmaceuticals and personal care products occupy a predominant position with respect to both utility and release into the ecosystem, thereby contributing to environmental pollution at alarming rates. Of the several methods identified to minimize the concentration of PPCPs, nanomaterial based photocatalysis seems to be a potential alternative for it being highly economical and eco-friendly. In this study, we synthesized Nickel zinc ferrite (Ni-ZF) [Nix Zn1-x Fe2O4 (x = 0, 0.3, 0.7)] nanoparticles with an average diameter of ∼400 nm by a co-precipitation method towards diclofenac degradation. The composite showed greater degrees of crystallinity devoid of any impurities. Nearly complete DCF degradation (∼99%) was achieved after 50 min reaction time with the nanoparticles at pH 7 for an initial DCF concentration of 50 mg/L. The degradation process followed a pseudo first-order rate law with the rate constant of 0.1657 min- 1. Microbial toxicity and phytotoxicity studies demonstrated negligible toxicity imposed by the contaminated water treated with the prepared composite, suggesting it as a promising photocatalyst benefitting in all aspects.


Asunto(s)
Diclofenaco , Nanopartículas , Catálisis , Diclofenaco/toxicidad , Ecosistema , Luz , Zinc
6.
Polymers (Basel) ; 14(5)2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35267799

RESUMEN

Biocompatibility is important for the 3D printing of resins used in medical devices and can be affected by photoinitiators, one of the key additives used in the 3D printing process. The choice of ingredients must be considered, as the toxicity varies depending on the photoinitiator, and unreacted photoinitiator may leach out of the polymerized resin. In this study, the use of ethyl (2,4,6-trimethylbenzoyl) phenylphosphinate (TPO-L) as a photoinitiator for the 3D printing of resin was considered for application in medical device production, where the cytotoxicity, colour stability, dimensional accuracy, degree of conversion, and mechanical/physical properties were evaluated. Along with TPO-L, two conventional photoinitiators, phenylbis (2,4,6-trimethylbenzoyl) phosphine oxide (BAPO) and diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide (TPO), were considered. A total of 0.1 mol% of each photoinitiator was mixed with the resin matrix to prepare a resin mixture for 3D printing. The specimens were printed using a direct light processing (DLP) type 3D printer. The 3D-printed specimens were postprocessed and evaluated for cytotoxicity, colour stability, dimensional accuracy, degree of conversion, and mechanical properties in accordance with international standards and the methods described in previous studies. The TPO-L photoinitiator showed excellent biocompatibility and colour stability and possessed with an acceptable dimensional accuracy for use in the 3D printing of resins. Therefore, the TPO-L photoinitiator can be sufficiently used as a photoinitiator for dental 3D-printed resin.

7.
Environ Pollut ; 289: 117864, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34352631

RESUMEN

In this work, we prepared nanocomposites of nickel-decorated manganese oxynitride on graphene nanosheets and demonstrated them as photocatalysts for degradation of acetylsalicylic acid (ASA). The catalyst exhibited a high degradation efficiency over ASA under visible light irradiation and an excellent structural stability after multiple uses. Compared to manganese oxide (MnO) and manganese oxynitride (MnON) nanoparticles, larger specific surface area and smaller band gap were observed for the nanocomposite accounting for the enhanced photocatalytic efficiency. Besides the compositional effect of the catalyst, we also examined the influence of various experimental parameters on the degradation of ASA such as initial concentration, catalyst dose, initial pH and additives. The best performance was obtained for the nanocomposite when the catalyst dose was 10 mg/mL and the initial pH 3. Detection of intermediates during photocatalysis showed that ASA undergoes hydroxylation, demethylation, aromatization, ring opening, and finally complete mineralization into CO2 and H2O by reactive species. For practical applications as a photocatalyst, cytotoxicity of the nanocomposite was also evaluated, which revealed its insignificant impact on the cell viability. These results suggest the nanocomposite of nickel-decorated manganese oxynitride on graphene nanosheets as a promising photocatalyst for the remediation of ASA-contaminated water.


Asunto(s)
Grafito , Aspirina , Luz , Manganeso , Níquel
8.
Materials (Basel) ; 13(24)2020 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-33317089

RESUMEN

Miniscrews have gained recent popularity as temporary anchorage devices in orthodontic treatments, where failure due to sinus perforations or damage to the neighboring roots have increased. Issues regarding miniscrews in insufficient interradicular space must also be resolved. This study aimed to evaluate the primary stability of miniscrews shorter than 6 mm and their feasibility in artificial bone with densities of 30, 40, and 50 pounds per cubic foot (pcf). The primary stability was evaluated by adjusting the intrabony miniscrew length, based on several physical properties: maximum insertion torque (MIT), maximum removal torque (MRT), removal angular momentum (RAM), horizontal resistance, and micromotion. The MIT and micromotion results demonstrated that the intrabony length of a miniscrew significantly affected its stability in low-density cortical bone, unlike cases with a higher cortical bone density (p < 0.05). The horizontal resistance, MRT, and RAM were affected by the intrabony length, regardless of the bone density (p < 0.05). Thus, the primary stability of miniscrews was affected by both the cortical bone density and intrabony length. The effect of the intrabony length was more significant in low-density cortical bone, where the implantation depth increased as more energy was required to remove the miniscrew. This facilitated higher resistance and a lower risk of falling out.

9.
Materials (Basel) ; 13(19)2020 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-33028011

RESUMEN

The increasing demand for orthodontic treatment over recent years has led to a growing need for the retrieval and reuse of titanium-based miniscrews to reduce the cost of treatment, especially in patients with early treatment failure due to insufficient primary stability. This in vitro study aimed to evaluate differences in the primary stability between initially inserted and re-inserted miniscrews within different cortical bone densities. Artificial bone was used to simulate cortical bone of different densities, namely 20, 30, 40, and 50 pound per cubic foot (pcf), where primary stability was evaluated based on maximum insertion torque (MIT), maximum removal torque (MRT), horizontal resistance, and micromotion. Scanning electron microscopy was used to evaluate morphological changes in the retrieved miniscrews. The MIT, MRT, horizontal resistance, and micromotion was better in samples with higher cortical bone density, thereby indicating better primary stability (P < 0.05). Furthermore, a significant reduction of MIT, MRT, and horizontal resistance was observed during re-insertion compared with the initial insertion, especially in the higher density cortical bone groups. However, there was no significant change in micromotion. While higher cortical bone density led to better primary stability, it also caused more abrasion to the miniscrews, thereby decreasing the primary stability during re-insertion.

10.
BMC Med Genet ; 21(1): 160, 2020 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-32807123

RESUMEN

BACKGROUND: Diabetes is mostly assessed by the fasting glucose level. Several studies reported that serum fasting glucose levels and cardiovascular disease are associated with MC4R. METHODS: A total of 4294 subjects participated in this study. There were 1810 subjects with cardiovascular disease among the 4294 subjects. We used multivariate linear regression models and multiple logistic regression analysis. RESULTS: Individuals with the TC/CC genotype had a 1.29-fold higher risk of diabetes than did those with the TT genotype when adjusting for age, sex, and BMI (OR, 1.29; 95% CI, 1.04-1.60). For healthy subjects, the association was significant in women (OR, 1.99; 95% CI, 1.01-3.93). Men with the TC/CC genotype had a 1.21-fold higher risk of cardiovascular disease than did those with the TT genotype when adjusting for age, sex, and BMI (OR, 1.21; 95% CI, 1.04-1.41). The relationship between MC4R and cardiovascular disease was stronger in lean men (OR, 1.40; 95% CI, 1.12-1.74, p = 0.0028) than in overweight men. CONCLUSIONS: This study suggests that the rs17782313 SNP in MC4R is related to diabetes and the SNP is also associated with cardiovascular disease in lean men.


Asunto(s)
Enfermedades Cardiovasculares/genética , Diabetes Mellitus Tipo 2/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple/genética , Receptor de Melanocortina Tipo 4/genética , Glucemia/metabolismo , Enfermedades Cardiovasculares/sangre , Diabetes Mellitus Tipo 2/sangre , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Oportunidad Relativa , República de Corea
11.
ChemSusChem ; 13(10): 2571-2576, 2020 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-32202374

RESUMEN

A general and straightforward way of preparing few-nanometer-sized well-separated MAPbIx Br3-x (MA=methylammonium) perovskite photosensitizers on the surface of an approximately 1 µm thick mesoporous TiO2 photoanode was suggested through a two-step sequential deposition of low-concentrated lead halides (0.10-0.30 m PbI2 or PbBr2 ) and methylammonium iodide/bromide (MAI/MABr). When those nanoscale MAPbIx Br3-x perovskites were incorporated as a photosensitizer in typical solid-state dye-sensitized solar cells (ss-DSSCs), it could be verified clearly by the capacitance analysis that nano-particulate MAPbI3 perovskites play the same role as that of a typical dye sensitizer (MK-2 molecule) although their size, composition, and structure are different.

12.
Food Sci Biotechnol ; 28(1): 165-174, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30815307

RESUMEN

Amylosucrases (ASase, EC 2.4.1.4) from Deinococcus geothermalis (DGAS) and Neisseria polysaccharea (NPAS) were heterologously expressed in Bacillus subtilis. While DGAS was successfully expressed, NPAS was not. Instead, NPAS was expressed in Escherichia coli. Recombinant DGAS and NPAS were purified using nickel-charged affinity chromatography and employed to modify daidzin to enhance its water solubility and bioavailability. Analyses by LC/MS revealed that the major products of transglycosylation using DGAS were daidzein diglucoside and daidzein triglucoside, whereas that obtained by NPAS was only daidzein diglucoside. The optimal bioconversion conditions for daidzein triglucoside, which was predicted to have the highest water-solubility among the daidzin derivatives, was determined to be 4% (w/v) sucrose and 250 mg/L daidzin in sodium phosphate pH 7.0, with a reaction time of 12 h. Taken together, we suggest that the yield and product specificity of isoflavone daidzin transglycosylation may be modulated by the source of ASase and reaction conditions.

13.
Biochem Biophys Res Commun ; 309(3): 619-24, 2003 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-12963035

RESUMEN

Although apoptosis contributes to myocardial cell death in the ischemia-reperfused heart, the molecular basis of apoptosis is poorly understood. Apoptosis-inducing factor (AIF) has been characterized as a caspase-independent death effector. Upon the induction of apoptosis, mitochondrial AIF is released to the cytoplasm and then enters the nucleus, in which it induces chromatin condensation and 50 kbp DNA fragmentation. In the present study, we examined the role of AIF in ischemia-reperfusion injury in isolated rat hearts. AIF was detected in the cytosolic and nuclear fractions of hearts subjected to ischemia-reperfusion, whereas it was detected only in the mitochondria of control hearts. Moreover, AIF release increased in a reperfusion time-dependent manner. Pulse field gel electrophoresis revealed that 50 kbp DNA fragments were produced by ischemia/reperfusion. In contrast, cytochrome c release and the activation of caspase-3 did not occur to a significant extent. Moreover, ischemic preconditioning attenuated the AIF release and the 50 kbp DNA fragmentation. These results suggest that AIF-dependent apoptosis is likely to attribute to myocardial cell death in the ischemia-reperfused heart and that it is related with the protective effect of ischemic preconditioning.


Asunto(s)
Apoptosis , Flavoproteínas/fisiología , Proteínas de la Membrana/fisiología , Miocardio/metabolismo , Animales , Factor Inductor de la Apoptosis , Caspasa 3 , Caspasas/fisiología , Núcleo Celular/metabolismo , Grupo Citocromo c/análisis , Citosol/metabolismo , Fragmentación del ADN , Flavoproteínas/análisis , Precondicionamiento Isquémico , Masculino , Proteínas de la Membrana/análisis , Mitocondrias/metabolismo , Daño por Reperfusión Miocárdica/etiología , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/patología , Miocardio/citología , Técnicas de Cultivo de Órganos , Transporte de Proteínas , Ratas , Ratas Sprague-Dawley
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