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1.
Eval Rev ; : 193841X241280681, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39250717

RESUMEN

Animal welfare is increasingly understood to be a key component of sustainable agricultural production. Southeast Asia and India are witnessing an emerging market for cage-free egg production. To evaluate the economic sustainability of cage-free policies in the region, it is critical to understand how this transition will affect farmers' costs and revenues. In this article, we provide an overview of the available information that can inform evaluations of cage-free egg production in Southeast Asia and India. Cage-free egg producers around the world tend to experience higher costs, but these costs are offset by higher revenues. As demand for cage-free eggs is stimulated in Southeast Asia and India by retailer or government policies, we expect that producers will be capable of meeting this demand. In Asia specifically, the dominant cost component is poultry feed. We conclude that the economic viability of egg production in the region is likely to be driven by feed prices and associated government policies, rather than production system per se.

2.
Heliyon ; 10(13): e33153, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39040400

RESUMEN

Doping and hybridization with other semiconductors are highly effective ways to address the limitations, including their weak response to visible light and significant recombination of photogenerated carriers. In addition, the assisted carbon on the catalyst surface and the structural design have the advantage of being catalytically active. Herein, visible-light-active N-doped C/Na2Ti6O13/TiO2 hollow spheres (denoted as N-C/NTO/TiO2 HS) were successfully prepared using a facile two-step method and evaluated for methylene blue (MB) aqueous solution degradation under visible-light irradiation. The as-obtained N-C/NTO/TiO2 HS demonstrated improved photocatalytic efficiency (94 %) and pseudo-first-order kinetic degradation rate (0.023 min-1). Moreover, after three cycles of testing, N-C/NTO/TiO2 HS showed a 91 % degradation rate in its photostability. The enhanced photocatalytic performance was attributed to the combined effects of N-doping, carbon species on the surface, and the coupling of TiO2 and Na2Ti6O13 using morphology engineering. Finally, based on the experimental results, a possible photocatalytic mechanism was proposed. This study provides a rational approach toward the development of high-performance titanate-based photocatalysts for solar energy-assisted wastewater treatment.

3.
Protein Pept Lett ; 31(3): 247-260, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38445693

RESUMEN

BACKGROUND: Fungal infections in plants, animals, and humans are widespread across the world. Limited classes of antifungal drugs to treat fungal infections and loss of drug efficacy due to rapidly evolving fungal strains pose a challenge in the agriculture and health sectors. Hence, the search for a new class of antifungal agents is imperative. Cyclotides are cyclic plant peptides with multiple bioactivities, including antifungal activity. They have six conserved cysteine residues forming three disulfide linkages (CI-CIV, CII-CV, CIII-CVI) that establish a Cyclic Cystine Knot (CCK) structure, making them extremely resistant to chemical, enzymatic, and thermal attacks. AIM: This in silico analysis of natural, plant-derived cyclotides aimed to assess the parameters that can assist and hasten the process of selecting the cyclotides with potent antifungal activity and prioritize them for in vivo/ in vitro experiments. OBJECTIVE: The objective of this study was to conduct in silico studies to compare the physicochemical parameters, sequence diversity, surface structures, and membrane-cyclotide interactions of experimentally screened (from literature survey) potent (MIC ≤ 20 µM) and non-potent (MIC > 20 µM) cyclotides for antifungal activity. METHODOLOGY: Cyclotide sequences assessed for antifungal activity were retrieved from the database (Cybase). Various online and offline tools were used for sequence-based studies, such as physicochemical parameters, sequence diversity, and neighbor-joining trees. Structure-based studies involving surface structure analysis and membrane-cyclotide interaction were also carried out. All investigations were conducted in silico. RESULTS: Physicochemical parameter values, viz. isoelectric point, net charge, and the number of basic amino acids, were significantly higher in potent cyclotides compared to non-potent cyclotides. The surface structure of potent cyclotides showed a larger hydrophobic patch with a higher number of hydrophobic amino acids. Furthermore, the membrane-cyclotide interaction studies of potent cyclotides revealed lower transfer free energy (ΔG transfer) and higher penetration depth into fungal membranes, indicating higher binding stability and membrane-disruption ability. CONCLUSION: These in silico studies can be applied for rapidly identifying putatively potent antifungal cyclotides for in vivo and in vitro experiments, which will ultimately be relevant in the agriculture and pharmaceutical sectors.


Asunto(s)
Antifúngicos , Ciclotidas , Hongos , Ciclotidas/química , Ciclotidas/farmacología , Antifúngicos/farmacología , Antifúngicos/química , Hongos/efectos de los fármacos , Simulación por Computador , Pruebas de Sensibilidad Microbiana , Secuencia de Aminoácidos , Proteínas de Plantas/química , Proteínas de Plantas/farmacología
4.
Carbohydr Polym ; 326: 121581, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38142087

RESUMEN

Klebsiella pneumoniae is one of the priority objects for the development of new therapies against infections. The species has been perceived as of limited variety of O antigens (11 O serotypes identified to date). That trait makes lipopolysaccharide an attractive target for protective antibodies. Nowadays, K. pneumoniae O antigens encoding genes are often analysed by bioinformatic tools, such as Kaptive, indicating higher actual diversity of the O antigen loci. One of the novel K. pneumoniae O loci for which the antigen structure has not been elucidated so far is OL101. In this study, four clinical isolates predicted as OL101 were characterized and found to have the O antigen structure composed of ß-Kdop-[→3)-α-l-Rhap-(1→4)-α-d-Glcp-(1→]n, representing a novel serotype O13. Identification of the ß-Kdop terminus was based on the analysis of the complete LPS molecule by the HR-MAS NMR spectroscopy. The bioinformatic analysis of 71,377 K. pneumoniae genomes from public databases (July 2023) revealed a notable OL101 prevalence of 6.55 %.


Asunto(s)
Infecciones por Klebsiella , Antígenos O , Humanos , Antígenos O/genética , Antígenos O/química , Klebsiella pneumoniae/genética , Serogrupo , Lipopolisacáridos/química
5.
J Colloid Interface Sci ; 656: 495-503, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38007941

RESUMEN

Given their plentiful reserves, impressive safety features, and economical pricing, aqueous zinc - ion batteries (ZIBs) have positioned themselves as strong competitors to lithium - ion batteries. Yet, the scarcity of available cathode materials poses a challenge to their continued development. In this study, a V2O5/V6O13 heterostructure has been synthesized using a one - pot hydrothermal approach and employed as the cathode material for ZIBs. As evidenced by both experimental and theoretical findings, V2O5/V6O13 heterostructure delivers a rapid electrons and ions diffusion kinetics promoted by the stable interface and strong electronic coupling with significant charge transfer between V2O5 and V6O13, as well as a stable interface achieved by adjusting V - O bond length. Consequently, the optimized V2O5/V6O13 heterostructure cathode of ZIBs demonstrates exceptional capacity (338 mAh g-1 at 0.1 A g-1), remarkable cycling stability (92.96 % retained after 1400 cycles at 1 A g-1). Through comprehensive theoretical calculations and ex situ characterization, the kinetic analysis and storage mechanism of Zn2+ are thoroughly investigated, providing a solid theoretical foundation for the advancement of novel V - based cathode materials aimed at enhancing the performance of ZIBs.

6.
Angew Chem Int Ed Engl ; 62(46): e202312310, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37795830

RESUMEN

Na2 Ti6 O13 (NTO) with high safety has been regarded as a promising anode candidate for sodium-ion batteries. In the present study, integrated modification of migration channels broadening, charge density re-distribution, and oxygen vacancies regulation are realized in case of Nb-doping and have obtained significantly enhanced cycling performance with 92 % reversible capacity retained after 3000 cycles at 3000 mA g-1 . Moreover, unexpected low-temperature performance with a high discharge capacity of 143 mAh g-1 at 100 mA g-1 under -15 °C is also achieved in the full cell. Theoretical investigation suggests that Nb preferentially replaces Ti3 sites, which effectively improves structural stability and lowers the diffusion energy barrier. What's more important, both the in situ X-ray diffraction (XRD) and in situ Raman furtherly confirm the robust spring effect of the Ti-O bond, making special charge compensation mechanism and respective regulation strategy to conquer the sluggish transport kinetics and low conductivity, which plays a key role in promoting electrochemical performance.

7.
Small ; 19(44): e2304130, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37381654

RESUMEN

Aqueous zinc-ion batteries have received continuous interests because of applying low-cost and eco-friendly aqueous electrolytes and having high safety. Beyond energetically to explore new-type cathode materials, it is of great significance to regulate the zinc storage behavior of the existing cathodes in order to understand the underlying working mechanism. Therefore, as a proof of concept, this work achieves the regulation of zinc storage behaviors of the tunnel structure tunnel structure B-phase vanadium dioxide (VO2 (B)) and vanadium oxide (V6 O13 ) cathodes via a simple chemical tungsten-doping induction approach. Under low-concentration tungsten-doping induction of 1, 2 and 3 at.%, the tunnel sizes of VO2 (B) can be controlled readily. Moreover, the V6 O13 with large size tunnels can be achieved by medium-concentration tungsten induction of 6 and 9 at.%. It is demonstrated that tungsten induced VO2 (B) can achieve zinc storage without lattice structure change via operando X-ray diffraction analyses. Remarkably, via operando and non-operando analyses, tungsten induced V6 O13 with lager size tunnels can realize the oriented 1D zinc ion intercalation/deintercalation. The further kinetics analysis shows that the zinc storage is mainly diffusion control, which is different from most of vanadium-based cathodes with capacitance control. This viable tungsten-doping induction strategy provides a new insight into achieving the controllable regulation of zinc storage behaviors.

8.
Biomed Mater ; 18(2)2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36758244

RESUMEN

The development of novel antibacterial nano-materials with synergistic biological effects has attracted extensive interest of the researchers. In the study, 0.5 mol% Ag and 0.5 mol% Cu co-doped K2Ti6O13(0.5 Ag-0.5 Cu-KTO) nanomaterial was successfully synthesized using two-step method of sol-gel and hydrothermal synthesis. The crystal structure of 0.5 Ag-0.5 Cu-KTO was the same as that of monoclinic K2Ti6O13. Ag ions and Cu ions were uniformly loaded on K2Ti6O13by replacing partial Ti ions, so that these antibacterial ions could be slowly released. High specific surface area of 0.5 Ag-0.5 Cu-KTO (337.6 m2g-1) provided more surface active sites for Ag-Cu doping and adsorption. More negative surface zeta potential (-32.83 mV in phosphate buffer solution and -21.45 mV in physiological saline solution, respectively) would be beneficial to prevent the aggregation of the nanowires in physiological environment. Under the same doping amount, compared to 1.0 mol% Cu doped K2Ti6O13, 0.5 Ag-0.5 Cu-KTO exhibited better antibacterial performance against gram-positive and gram-negative bacteria at only 100 µg ml-1dose concentration, near to 1.0 mol% Ag doped K2Ti6O13(1.0 Ag-KTO). And 0.5 Ag-0.5 Cu-KTO showed more excellent biocompatibility than 1.0 Ag-KTO, which was attribute to the introduction of Cu ions effectively decreasing the hemolytic and cytotoxic risks from Ag ions. As expected, the synthesized 0.5 Ag-0.5 Cu-KTO nanowires demonstrated excellent structural stability, high antibacterial activity, good hemocompatibility and cytocompatibility owing to the synergistic effects of Cu and Ag ions. 0.5 Ag-0.5 Cu-KTO nanowires will be a promising antimicrobial candidate for biomedical applications.


Asunto(s)
Antibacterianos , Nanocables , Antibacterianos/química , Titanio/química , Bacterias Gramnegativas , Bacterias Grampositivas , Iones
9.
Materials (Basel) ; 15(23)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36500070

RESUMEN

V6O13 thin films were deposited on indium-doped tin oxide (ITO) conductive glass by a concise low-temperature liquid-phase deposition method and through heat treatment. The obtained films were directly used as electrodes without adding any other media. The results indicate that the film annealed at 400 °C exhibited an excellent cycling performance, which remained at 82.7% of capacity after 100 cycles. The film annealed at 400 °C with diffusion coefficients of 6.08 × 10-12 cm2·s-1 (Li+ insertion) and 5.46 × 10-12 cm2·s-1 (Li+ extraction) in the V6O13 film electrode. The high diffusion coefficients could be ascribed to the porous morphology composed of ultrathin nanosheets. Moreover, the film endured phase transitions during electrochemical cycling, the V6O13 partially transformed to Li0.6V1.67O3.67, Li3VO4, and VO2 with the insertion of Li+ into the lattice, and Li0.6V1.67O3.67, Li3VO4, and VO2 partially reversibly transformed backwards to V6O13 with the extraction of Li+ from the lattice. The phase transition can be attributed to the unique structure and morphology with enough active sites and ions diffusion channels during cycles. Such findings reveal a bright idea to prepare high-performance cathode materials for LIBs.

10.
Micromachines (Basel) ; 13(11)2022 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-36363845

RESUMEN

Low loss Ruddlesden-Popper (RP) series, i.e., (Sr1-xCax)5Ti4O13, 0.0 ≤ x ≤ 0.06, has been synthesized by a mixed oxide route. In this work, the substitution of Ca2+ cation in Sr5Ti4O13 sintered ceramics was chosen to enhance the structural, optical, and dielectric properties of the product. It was found that the Ca2+ content has significant effects on enhancing the dielectric properties as compared to Mn and glass additions. It was observed that the relative density, band gap energy, and dielectric loss (tangent loss) increase while relative permittivity decreases along with Ca2+ content. High relative density (96.7%), low porosity, and high band gap energy (2.241 eV) values were obtained in (Sr1-xCax)5Ti4O13, 0.0 ≤ x ≤ 0.06 sintered ceramics. These results will play a key role in the application of dielectric resonators.

11.
Molecules ; 27(19)2022 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-36234946

RESUMEN

This study reports a facile approach for constructing low-cost and remarkable electroactivity iron vanadate (Fe-V-O) semiconductor material to be used as a photoelectrochemical sensor for dopamine detection. The structure and morphology of the iron vanadate obtained by the Successive Ionic Adsorption and Reaction process were critically characterized, and the photoelectrochemical characterization showed a high photoelectroactivity of the photoanode in visible light irradiation. Under best conditions, dopamine was detected by chronoamperometry at +0.35 V vs. Ag/AgCl, achieving two linear response ranges (between 1.21 and 30.32 µmol L-1, and between 30.32 and 72.77 µmol L-1). The limits of detection and quantification were 0.34 and 1.12 µmol L-1, respectively. Besides, the accuracy of the proposed electrode was assessed by determining dopamine in artificial cerebrospinal fluid, obtaining recovery values ranging from 98.7 to 102.4%. The selectivity was also evaluated by dopamine detection against several interferent species, demonstrating good precision and promising application for the proposed method. Furthermore, DFT-based electronic structure calculations were also conducted to help the interpretation. The dominant dopamine species were determined according to the experimental conditions, and their interaction with the iron vanadate photoanode was proposed. The improved light-induced DOP detection was likewise evaluated regarding the charge transfer process.


Asunto(s)
Técnicas Biosensibles , Dopamina , Técnicas Biosensibles/métodos , Dopamina/química , Técnicas Electroquímicas/métodos , Electrodos , Hierro , Luz , Límite de Detección , Vanadatos
12.
ACS Appl Mater Interfaces ; 14(11): 13836-13847, 2022 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-35286068

RESUMEN

Both 3-hydroxy-2-butanone and triethylamine are highly toxic and harmful to human health, and their chronic inhalation can cause respiratory diseases, eye lesions, dermatitis, headache, dizziness, drowsiness, and even fatality. Developing sensors for detecting such toxic gases with low power consumption, high response with superselectivity, and stability is crucial for healthcare and environmental monitoring. This study presents a typical gas sensor fabricated based on AuPdO modified Cu-doped K2W4O13 nanowires, which can selectively detect 3-hydroxy-2-butanone and triethylamine at 120 and 200 °C, respectively. The sensor displays excellent sensing performance at reduced operating temperature, high selectivity, fast response/recovery, and stability, which can be attributed to a synergistic effect of Cu dopants and AuPdO nanoparticles on the K2W4O13 host. The enhanced sensing response and selectivity could be attributed to the oxygen vacancies/defects, bandgap excitation, the electronic sensitization, the reversible redox reaction of PdO and Cu, the cocatalytic activity of AuPdO, and Schottky barrier contacts at the interface of tungsten oxide and Au. The significant variations in the activation capacities of Cu-doped K2W4O13, Pd/PdO, and Au nanoparticles toward 3H-2B and TEA, and the diffusion depth of the two gases in the coated sensing layer may cause dual selectivity. The designed gas sensor materials can serve as a sensitive target for detecting toxic biomarkers and hold broad application prospects in food and environmental safety inspection.

13.
Toxicol Rep ; 8: 1803-1813, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34760624

RESUMEN

Earlier reports have shown that Cyclophosphamide (CYCP), an anti-malignant drug, elicited cytotoxicity; and that naringin has several beneficial potentials against oxidative stress and dyslipidaemias. We investigated the influence of naringin on free radical scavenging, cellular integrity, cellular ATP, antioxidants, oxidative stress, and lipid profiles in the CYCP-induced erythrocytotoxicity rat model. Rats were pretreated orally by gavage for fourteen consecutive days with three doses (50, 100, and 200 mg/kg) naringin before single CYCP (200 mg/kg, i.p.) administration. Afterwards, the rats were sacrificed. Naringin concentrations required for 50 % scavenging hydrogen peroxide and nitric oxide radical were 0.27 mg/mL and 0.28 mg/mL, respectively. Naringin pretreatment significantly (p < 0.05) protected erythrocytes plasma membrane architecture and integrity by abolishing CYCP-induced decrease in the activity of erythrocyte LDH (a marker of ATP). Pretreatment with naringin remarkably (p < 0.05) reversed CYCP-induced decreases in the erythrocytes glutathione levels, activities of glutathione-S-transferase, catalase, glutathione peroxidase, and glutathione reductase; attenuated CYCP-mediated increases in erythrocytes levels of malondialdehyde, nitric oxide, and major lipids (cholesterol, triacylglycerol, phospholipids, and non-esterified fatty acids). Taken together, different acute pretreatment doses of naringin might avert CYCP-mediated erythrocytes dysfunctions via its antioxidant, free-radical scavenging, and anti-dyslipidaemia properties.

14.
ACS Appl Mater Interfaces ; 13(32): 38239-38247, 2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-34342420

RESUMEN

The difficulty of adsorption and activation of CO2 at the catalytic site and rapid recombination of photogenerated charge carriers severely restrict the CO2 conversion efficiency. Here, we fabricate a novel alkaline Co(OH)2-decorated ultrathin 2D titanic acid nanosheet (H2Ti6O13) catalyst, which rationally couples the structural and functional merits of ultrathin 2D supports with catalytically active Co species. Alkaline Co(OH)2 beneficially binds and activates CO2 molecules, while monolayer H2Ti6O13 acts as an electron relay that bridges a photosensitizer with Co(OH)2 catalytic sites. As such, photoexcited charges can be efficiently channeled from light absorbers to activated CO2 molecules through the ultrathin hybrid Co(OH)2/H2Ti6O13 composite, thereby producing syngas (CO/H2 mixture) from photoreduction of CO2. High evolution rates of 56.5 µmol h-1 for CO and 59.3 µmol h-1 for H2 are achieved over optimal Co(OH)2/H2Ti6O13 by visible light illumination. In addition, the CO/H2 ratio can be facilely tuned from 1:1 to 1:2.4 by changing the Co(OH)2 content, thus presenting a feasible approach to controllably synthesize different H2/CO mixtures for target applications.

15.
Biosens Bioelectron ; 191: 113452, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34186304

RESUMEN

Photoinduced charge transfer (PICT) plays a crucial role in the chemical mechanism of surface-enhanced Raman scattering (SERS), in which small organic molecules are generally used as probes. Herein, semiconducting K2Ti6O13 nanowires (NWs) are synthesized and are found to exhibit high SERS activity probed by 4-mercaptobenzoic acid (4-MBA). Density functional theory (DFT) calculations reveal high-efficiency CT on the K2Ti6O13 nanowires. Furthermore, PICT on the K2Ti6O13 NWs is for the first time evidenced by a redox protein, cytochrome c (Cyt c). Under optimized experimental conditions, the transformation of oxidized Cyt c to its reduced state clearly verifies the electron transfer (ET) from the K2Ti6O13 nanowire to the protein. The ET mechanism is explored based on energy levels of semiconductors and molecular dynamics simulations, thus revealing the importance of energy level matching and electron tunneling from the semiconductor surface to the redox center. This study indicates a great potential of multiple-layered K2Ti6O13 NWs in the application of SERS on semiconducting materials and more importantly, it provides a new route for the rational design of protein-semiconductor interfaces for investigating electron transfer processes of redox proteins and biocatalytic reactions.


Asunto(s)
Técnicas Biosensibles , Nanocables , Electrones , Oxidación-Reducción , Titanio
16.
Materials (Basel) ; 14(4)2021 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-33669952

RESUMEN

New zinc metaborate Zn4B6O13-willemite Zn2SiO4 composites were investigated as promising materials for LTCC (low temperature cofired ceramics) substrates of microelectronic circuits for submillimeter wave applications. Composites were prepared as bulk ceramics and LTCC multilayer structures with cofired conductive thick films. The phase composition, crystal structure, microstructure, sintering behavior, and dielectric properties were studied as a function of willemite content (0, 10, 13, 15, 20, 40, 50, 60, 100 wt %). The dielectric properties characterization performed by THz time domain spectroscopy proved the applicability of the composites at very high frequencies. For the 87% Zn4B6O13-13% Zn2SiO4 composite, the best characteristics were obtained, which are suitable for LTCC submillimeter wave applications. These were a low sintering temperature of 930 °C, compatibility with Ag-based conductors, a low dielectric constant (5.8 at 0.15-1.1 THz), a low dissipation factor (0.006 at 1 THz), and weak frequency and temperature dependences of dielectric constant.

17.
Chemistry ; 27(11): 3875-3886, 2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-32852862

RESUMEN

Na2 Ti3 O7 (NTO) is considered a promising anode material for Na-ion batteries due to its layered structure with an open framework and low and safe average operating voltage of 0.3 V vs. Na+ /Na. However, its poor electronic conductivity needs to be addressed to make this material attractive for practical applications among other anode choices. Here, we report a safe, controllable and affordable method using urea that significantly improves the rate performance of NTO by producing surface defects such as oxygen vacancies and hydroxyl groups, and the secondary phase Na2 Ti6 O13 . The enhanced electrochemical performance agrees with the higher Na+ ion diffusion coefficient, higher charge carrier density and reduced bandgap observed in these samples, without the need of nanosizing and/or complex synthetic strategies. A comprehensive study using a combination of diffraction, microscopic, spectroscopic and electrochemical techniques supported by computational studies based on DFT calculations, was carried out to understand the effects of this treatment on the surface, chemistry and electronic and charge storage properties of NTO. This study underscores the benefits of using urea as a strategy for enhancing the charge storage properties of NTO and thus, unfolding the potential of this material in practical energy storage applications.

18.
ACS Appl Mater Interfaces ; 12(38): 42942-42948, 2020 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-32833420

RESUMEN

Nonlinear optical crystals play important roles in modern laser science and technology. However, the design and growth of new nonlinear optical (NLO) materials is still a challenging issue for researchers. Due to the excellent performance of Mg3B7O13Cl crystal, we paid attention to the optimization of its structure, in order to find new NLO materials with favorable properties. Here, Zn3B7O13Cl crystals were obtained by a high-temperature solution method. Its structure was determined to be the trigonal symmetry with a polar space group of R3c, which is more highly symmetric than that of Mg3B7O13Cl (Pca21). The experimental and theoretical investigations demonstrated that the title compound exhibits a short absorption cutoff (band gap ∼6.53 eV), moderate SHG responses (2.2 times that of KDP at 1064 nm), and the improved birefringence, which results from the large distortion and anisotropy of borate groups and zinc polyhedrons. Therefore, the structural modification of Mg3B7O13Cl by zinc cations achieves a balance between the deep-ultraviolet transparency, the nonlinear optical effect, and the moderate birefringence, which is very significant for the design of practical NLO materials.

19.
Stem Cell Res Ther ; 11(1): 77, 2020 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-32085810

RESUMEN

BACKGROUND: Induced pluripotent stem cells (iPSCs) exhibit limitless pluripotent plasticity and proliferation capability to provide an abundant cell source for tissue regenerative medicine. Thus, inducing iPSCs toward a specific differentiation direction is an important scientific question. Traditionally, iPSCs have been induced to chondrocytes with the help of some small molecules within 21-36 days. To speed up the differentiation of iPSCs, we supposed to utilize bioactive ceramics to assist chondrogenic-induction process. METHODS: In this study, we applied ionic products (3.125~12.5 mg/mL) of the lithium-containing bioceramic (Li2Ca4Si4O13, L2C4S4) and individual Li+ (5.78~23.73 mg/L) in the direct chondrogenic differentiation of human iPSCs. RESULTS: Compared to pure chondrogenic medium and extracts of tricalcium phosphate (TCP), the extracts of L2C4S4 at a certain concentration range (3.125~12.5 mg/mL) significantly enhanced chondrogenic proteins Type II Collagen (COL II)/Aggrecan/ SRY-Box 9 (SOX9) synthesis and reduced hypertrophic protein type X collagen (COL X)/matrix metallopeptidase 13 (MMP13) production in iPSCs-derived chondrocytes within 14 days, suggesting that these newly generated chondrocytes exhibited favorable chondrocytes characteristics and maintained a low-hypertrophy state. Further studies demonstrated that the individual Li+ ions at the concentration range of 5.78~23.73 mg/L also accelerated the chondrogenic differentiation of iPSCs, indicating that Li+ ions played a pivotal role in chondrogenic differentiation process. CONCLUSIONS: These findings indicated that lithium-containing bioceramic with bioactive specific ionic components may be used for a promising platform for inducing iPSCs toward chondrogenic differentiation and cartilage regeneration.


Asunto(s)
Condrocitos/efectos de los fármacos , Condrogénesis/efectos de los fármacos , Hipertrofia/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Litio/uso terapéutico , Medicina Regenerativa/métodos , Diferenciación Celular , Células Cultivadas , Humanos
20.
Agric Econ ; 50(5): 567-580, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31762523

RESUMEN

Effective agricultural extension is key to improving productivity, increasing farmers' access to information, and promoting more diverse sets of crops and improved methods of cultivation. In India, however, the coverage of agricultural extension workers and the relevance of extension advice is poor. We investigate whether a women's self-help group (SHG) platform could be an effective way of improving access to information, women's empowerment in agriculture, agricultural practices, and production diversity. We use cross-sectional data on close to 1,000 women from five states in India and employ nearest-neighbor matching models to match SHG and non-SHG women along a range of observed characteristics. We find that participation in an SHG increases women's access to information and their participation in some agricultural decisions, but has limited impact on agricultural practices or outcomes, possibly due to financial constraints, social norms, and women's domestic responsibilities. SHGs need to go beyond provision of information to changing the dynamics around women's participation in agriculture to effectively translate knowledge into practice.

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