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1.
J Environ Sci (China) ; 148: 263-273, 2025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39095162

RESUMO

The adsorption of pollutants can not only promote the direct surface reaction, but also modify the catalyst itself to improve its photoelectric characteristics, which is rarely studied for water treatment with inorganic photocatalyst. A highly crystalline BiOBr (c-BiOBr) was synthesized by a two-step preparation process. Owing to the calcination, the highly crystalline enhanced the interface interaction between pollutant and c-BiOBr. The complex of organic pollutant and [Bi2O2]2+ could promote the active electron transfer from the adsorbed pollutant to c-BiOBr for the direct pollutant degradation by holes (h+). Moreover, the pollutant adsorption actually modified c-BiOBr and promoted more unpaired electrons, which would coupling with the photoexcitation to promote generate more O2•-. The molecular modification effect derived from pollutant adsorption significantly improved the removal of pollutants. This work strongly deepens the understanding of the molecular modification effect from the pollutant adsorption and develops a novel and efficient approach for water treatment.


Assuntos
Poluentes Químicos da Água , Adsorção , Poluentes Químicos da Água/química , Catálise , Bismuto/química , Purificação da Água/métodos
2.
Environ Geochem Health ; 46(9): 358, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39088124

RESUMO

Groundwater is the main source of water for more than 2 billion people worldwide. In southern Brazil, the Crystalline Basement Aquifer System is composed of strategic groundwater reservoirs. Groundwater is mostly taken from shallow wells, and it is often used without any treatment, which poses a risk to public health. The present study aims to evaluate shallow groundwater quality and the geochemistry of shallow and deep groundwater located in the municipality of Canguçu, southern Brazil. The physicochemical and microbiological parameters of groundwater samples collected from shallow wells were monitored and analyzed using ANOVA variance analysis and water quality index (CCME WQI) approaches. Also, the results were compared with secondary data from deep wells. The monitored shallow wells had thermotolerant coliforms, Escherichia coli, pH, potassium, manganese, iron, and nitrate in disagreement with the guidelines of the World Health Organization. Moreover, variance analysis showed that the parameters temperature, dissolved oxygen, pH, chloride, and magnesium were the most influenced by seasonal variations. According to the CCME WQI, most samples had good quality (60%), 28% had fair quality, and 12% had poor quality. In addition, the field campaigns with higher precipitation rates also presented fair quality. Therefore, most of the shallow groundwater quality is affected by surface pollutants from the urban area, aggravated in rainy periods. Whereas deep groundwater is influenced by geochemistry mechanisms. The results revealed the risk of water consumption for public health and the urgent need for better maintenance of these wells and water treatment implementation.


Assuntos
Monitoramento Ambiental , Água Subterrânea , Qualidade da Água , Água Subterrânea/química , Brasil , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio , Microbiologia da Água , Estações do Ano , Poços de Água , Nitratos/análise
3.
Appl Spectrosc ; : 37028241268158, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39094004

RESUMO

The aim of this work was the development and morphological/chemical, spectroscopic, and structural characterization of titanium dioxide, niobium pentoxide, and titanium:niobium (Ti:Nb) oxides, as well as materials modified with ruthenium (Ru) with the purpose of provide improvement in photoactivation capacity with visible sunlight radiation. The new materials synthesized by the sol-gel methodology were characterized by the following techniques: scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), photoacoustic spectroscopy, and X-ray diffraction. The SEM-EDS analyses showed the high purity of the bases, and the modified samples showed the adsorption of ruthenium on the surface with the crystals formation and visible agglomerates for higher calcination temperature. The nondestructive characterization of photoacoustic spectroscopy in the ultraviolet-visible (UV-Vis) region suggested that increasing calcination temperature promoted changes in chemical structures and an apparent decrease in gap energy. The separation of superimposed absorption bands referring to charge transfers from the ligand to the metal and the nanodomains of the transition metals suggested the possible absorption centers present at the absorption threshold of the analyzed oxides. Through the XRD analysis, the formation of stable phases such as T-Nb16.8O42, o-Nb12O29, and rutile was observed at a lower temperature level, suggesting pore induction and an increase in surface area for the oxides studied, at a calcination temperature below that expected by the related literature. In addition, the synthesis with a higher temperature level altered the previously existing morphologies of the Ti:Nb, base and modified with Ru, forming the new mixed crystallographic phases Ti2Nb10O29 and TiNb2O7, respectively. As several semiconductor oxide applications aim to reduce costs with photoexcitation in visible light, the modified Ti:Ru oxide calcined at a temperature of 800 °C and synthesized according to the sol-gel methodology used in this work is suggested as the optimum preparation point. This material presented the formation of a stable crystallographic phase (rutile), a significant decrease in gap energy (2.01 eV), and a visible absorption threshold (620 nm).

4.
Eur J Ophthalmol ; : 11206721241267028, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39094558

RESUMO

OBJECTIVE: This study aims to examine the characteristics and influencing factors of crystalline lens tilt and decentration in ultra-high myopic cataract patients, as measured by the CASIA2. METHODS AND ANALYSIS: 60 eyes scheduled for cataract surgery with an axial length (AL) ≥ 28 mm were included. The IOLMaster700 was utilized to measure AL and the white-to-white (WTW) distance. The CASIA2 was employed to measure front curvature radius (FCR), crystalline lens tilt, and crystalline lens decentration. The relationships between lens tilt, decentration, and related factors were evaluated. RESULTS: The degree of lens tilt was 4.62 ± 2.44°, and the decentration was 0.20 (Q1 0.13, Q3 0.28) mm. Among the 60 eyes, 11 (18.3%) had a tilt ≥7°, and 6 (10%) had a decentratiolens tilt ≥7° (P = 0.038, P = 0.018). Eyes with AL >30.00 mm and FCR <8.45 mm had a higher degree of lens tilt. Additionally, a tilt ≥7° was associated with a greater decentration (P = 0.032), n. CONCLUSION: Preoperative crystalline lenses in eyes with ultra-high myopia and cataract exhibit certain degrees of tilt and decentration. An AL >30 mm is a risk factor for a lens tilt ≥7° and an decentration ≥0.4 mm. An FCR <8.45 mm is a risk factor for increased lens tilt, and a tilt ≥7° is a risk factor for increased lens decentrati ≥ 0.4 mm. An increase in AL and FCR <8.45 mm were risk factors for a and eyes with AL >30.00 mm had a higher degree of decentration (P = 0.005).

5.
Sci Total Environ ; 948: 174846, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39032747

RESUMO

This study presents a Life Cycle Assessment (LCA) of photovoltaic (PV) electricity production in Italy based on the composition of the current and future Italian PV scenario. Using detailed and site-specific data, the actual composition of the Italian mix of PV technologies at the end of 2022 and those expected for 2030 were defined. A new LCA modelling of the most relevant PV technologies was carried out using updated and reliable inventory data. The impact assessment was performed adopting the most relevant impact categories of Environmental Footprint Method v. 3.1. The environmental profiles of the two Italian PV scenarios (PV Scenario_2021 and PV Scenario_2030) analysed in this study were compared with that of the PV scenario achievable using unaltered Ecoinvent v 3.9.1 datasets specific to Italian. The obtained results highlighted that the use of Ecoinvent datasets and hypothesis entails a significant overestimation of the environmental impacts of photovoltaic electricity production in Italy; showing higher impacts ranging from 70 % to 30 % (depending on the impact category considered) and the main key factors affecting the results were investigated. However, the wide impacts gaps pointed out the importance of conducting representative LCA studies of the fast-growing and evolving PV context of the countries, to provide reliable impact results to policy makers and to other researchers and who need to include the PV electricity generation in their studies. Furthermore, the environmental performance analysis of the two Italian PV scenarios highlighted the higher sustainability of the PV electricity production in the next years (PV Scenario_2030) for all considered impact categories (except for land use). This improvement can be primarily attributed to the higher annual energy yield and the greater utilization of high-efficiency PV technologies, along with the expansion of ground-mounted PV plants.

6.
Sci Total Environ ; : 174976, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39047838

RESUMO

Environmental exposure to crystalline silica (CS) particles is common and occurs during natural, industrial, and agricultural activities. Prolonged inhalation of CS particles can cause silicosis, a serious and incurable pulmonary fibrosis disease. However, the underlying mechanisms remain veiled. Herein, we aim to elucidate the novel mechanisms of interleukin-11 (IL-11) driving fibroblast metabolic reprogramming during the development of silicosis. We observed that CS exposure induced lung fibrosis in mice and activated fibroblasts, accompanied by increased IL-11 expression and metabolic reprogramming switched from mitochondrial respiration to glycolysis. Besides, we innovatively uncovered that elevated IL-11 promoted the glycolysis process, thereby facilitating the fibroblast-myofibroblast transition (FMT). Mechanistically, CS-stimulated IL-11 activated the extracellular signal-regulated kinase (ERK) pathway and the latter increased the expression of hypoxia inducible factor-1α (HIF-1α) via promoting the translation and delaying the degradation of the protein. HIF-1α further facilitated glycolysis, driving the FMT process and ultimately the formation of silicosis. Moreover, either silence or neutralization of IL-11 inhibited glycolysis augmentation and attenuated CS-induced lung myofibroblast generation and fibrosis. Overall, our findings elucidate the role of IL-11 in promoting fibroblast metabolic reprogramming through the ERK-HIF-1α axis during CS-induced lung fibrosis, providing novel insights into the molecular mechanisms and potential therapeutic targets of silicosis.

7.
Sci Rep ; 14(1): 16718, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030219

RESUMO

For first time, new innovative ruthenium N3-Dye anchored with selenium (Se) and N3 dye anchored with sulphur atoms were synthesized in a good yield. Dyes are applied and evaluated in performance of dye sensitized solar cell. N3-Se dye showed superior photochemical& electrochemical behavior and high rate electron transfer across anode surface than N3-S dye. The better optical and electrochemical activities would make Se-dye a candidate for applications in solar cells. Half life time of N3-S showed a single exponential decay with an average lifetime of 0.8 ns. For N3-Se dye, decay curve was fitted by sum two exponential functions with 75% and 25% counts have 2.5 ns and 30 ns respectively. Solar cells were fabricated and analyzed to determine their solar-to-electric conversion efficiency under standard AM 1.5 sunlight. Commercial N3 dyes showed current density (Jsc) of 17.813 mA cm-2, open circuit potential (Voc) of 0.678 V, filling factor (FF) of 0.607 and conversion efficiencies (η) of 7.3%. Corresponding values for N3-S dye, Jsc 11.2 mA cm-2, Voc 0.650 V, FF 0.681 and η 5%. Se-N3 dye, showed Jsc = 6.670 mA cm-2, Voc = 0.6004 V, FF = 0.77 and η = 3.09%. Long lifetime of N3-Se caused low practical performance.

8.
ACS Appl Mater Interfaces ; 16(28): 36688-36695, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38963145

RESUMO

High-mobility and color-tunable highly emissive organic semiconductors (OSCs) are highly promising for various optoelectronic device applications and novel structure-property relationship investigations. However, such OSCs have never been reported because of the great trade-off between mobility, emission color, and emission efficiency. Here, we report a novel strategy of molecular conformation-induced unique crystalline polymorphism to realize the high mobility and color-tunable high emission in a novel OSC, 2,7-di(anthracen-2-yl) naphthalene (2,7-DAN). Interestingly, 2,7-DAN has unique crystalline polymorphism, which has an almost identical packing motif but slightly different molecular conformation enabled by the small bond rotation angle variation between anthracene and naphthalene units. More remarkably, the subtle covalent bond rotation angle change leads to a big change in color emission (from blue to green) but does not significantly modify the mobility and emission efficiency. The carrier mobility of 2,7-DAN crystals can reach up to a reliable 17 cm2 V-1 s-1, which is rare for the reported high-mobility OSCs. Based on the unique phenomenon, high-performance light-emitting transistors with blue to green emission are simultaneously demonstrated in an OSC crystal. These results open a new way for designing emerging multifunctional organic semiconductors toward next-generation advanced molecular (atomic)-scale optoelectronics devices.

9.
Small ; : e2404192, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004849

RESUMO

The tunable pore walls and skeletons render covalent organic frameworks (COFs) as promising absorbents for gold (Au) ion. However, most of these COFs suffered from low surface areas hindering binding sites exposed and weak binding interaction resulting in sluggish kinetic performance. In this study, COFs have been constructed with synergistic linker and linkage for high-efficiency Au capture. The designed COFs (PYTA-PZDH-COF and PYTA-BPDH-COF) with pyrazine or bipyridine as linkers showed high surface areas of 1692 and 2076 m2 g‒1, providing high exposed surface areas for Au capture. In addition, the Lewis basic nitrogen atoms from the linkers and linkages are easily hydronium, which enabled to fast trap Au via coulomb force. The PYTA-PZDH-COF and PYTA-BPDH-COF showed maximum Au capture capacities of 2314 and 1810 mg g-1, higher than other reported COFs. More importantly, PYTA-PZDH-COF are capable of rapid adsorption kinetics with achieving 95% of maximum binding capacity in 10 min. The theoretical calculation revealed that the nitrogen atoms in linkers and linkages from both COFs are simultaneously hydronium, and then the protonated PYTA-PZDH-COF are more easily binding the AuCl4 ‒, further accelerating the binding process. This study gives the a new insight to design COFs for ion capture.

10.
Ann Work Expo Health ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007362

RESUMO

INTRODUCTION: Respirable crystalline silica (RCS) exposures in tanzanite gem mining have been linked to tuberculosis and silicosis among miners. We conducted a plot study to assess RCS exposures and to introduce safer mining practices in one small-scale underground tanzanite mine. MATERIALS AND METHODS: Personal and area air samples for RCS were collected during tanzanite mining operations before and after improved work practices employed to reduce exposures and analyzed using X-ray diffraction. Area samples were collected at the rest area, located approximately 300 m underground and 100 m from other work activities. Improved practices included the use of wet drilling methods and drilling with new bits. RESULTS: A total of 33 personal and 4 area air samples were collected. Pre-intervention, mean exposures for all operations, drilling operations, non-drilling activities, and area samples were 122 mg/m3, 247 mg/m3, 34.3 mg/m3, and 1.95 mg/m3, respectively which exceeded the U.S. OSHA Permissible Exposure Limit (PEL) by 2,440 times for all operations, by 4,946 times for drilling operations, by 686 times for non-drilling activities and 39 times for area samples collected at an underground rest area. The post-intervention results showed a 99% reduction of RCS exposures for wet drilling operations, 98.5% reduction for non-drilling activities, and 36% reduction for area samples. Despite improvements, post-intervention RCS exposures during drilling had a mean of 2.08 mg/m3 or more than 41 times the OSHA PEL. CONCLUSIONS: We successfully piloted a program to work with small-scale tanzanite miners to reduce RCS exposures and raise awareness about the occupational health risks of RCS, though additional measures are recommended to further reduce RCS exposures. Similar programs should be taken to scale throughout underground mining sites in Tanzania and other countries.

11.
Cell Commun Signal ; 22(1): 359, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992691

RESUMO

PURPOSE: Bietti crystalline dystrophy (BCD) is an inherited retinal degeneration disease caused by mutations in the CYP4V2 gene. Currently, there is no clinical therapy approach available for BCD patients. Previous research has suggested that polyunsaturated fatty acids (PUFAs) may play a significant role in the development of BCD, implicating the involvement of ferroptosis in disease pathogenesis. In this work, we aimed to investigate the interplay between ferroptosis and BCD and to detect potential therapeutic strategies for the disease. METHODS: Genetic-edited RPE cell line was first established in this study by CRISPR-Cas9 technology. Cyp4v3 (the homologous gene of human CYP4V2) knock out (KO) mice have also been used. Lipid profiling and transcriptome analysis of retinal pigment epithelium (RPE) cells from Cyp4v3 KO mice have been conducted. Ferroptosis phenotypes have been first investigated in BCD models in vitro and in vivo, including lipid peroxidation, mitochondrial changes, elevated levels of reactive oxygen species (ROS), and altered gene expression. Additionally, an iron chelator, deferiprone (DFP), has been tested in vitro and in vivo to determine its efficacy in suppressing ferroptosis and restoring the BCD phenotype. RESULTS: Cyp4v3 KO mice exhibited progressive retinal degeneration and lipid accumulation, similar to the BCD phenotype, which was exacerbated by a high-fat diet (HFD). Increased levels of PUFAs, such as EPA (C22:5) and AA (C20:4), were observed in the RPE of Cyp4v3 KO mice. Transcriptome analysis of RPE in Cyp4v3 KO mice revealed changes in genes involved in iron homeostasis, particularly an upregulation of NCOA4, which was confirmed by immunofluorescence. Ferroptosis-related characteristics, including mitochondrial defects, lipid peroxidation, ROS accumulation, and upregulation of related genes, were detected in the RPE both in vitro and in vivo. Abnormal accumulation of ferrous iron was also detected. DFP, an iron chelator administration suppressed ferroptosis phenotype in CYP4V2 mutated RPE. Oral administration of DFP also restored the retinal function and morphology in Cyp4v3 KO mice. CONCLUSION: This study represented the first evidence of the substantial role of ferroptosis in the development of BCD. PUFAs resulting from CYP4V2 mutation may serve as substrates for ferroptosis, potentially working in conjunction with NCOA4-regulated iron accumulation, ultimately leading to RPE degeneration. DFP administration, which chelates iron, has demonstrated its ability to reverse BCD phenotype both in vitro and in vivo, suggesting a promising therapeutic approach in the future.


Assuntos
Distrofias Hereditárias da Córnea , Ferroptose , Camundongos Knockout , Epitélio Pigmentado da Retina , Animais , Ferroptose/genética , Ferroptose/efeitos dos fármacos , Distrofias Hereditárias da Córnea/genética , Distrofias Hereditárias da Córnea/patologia , Distrofias Hereditárias da Córnea/metabolismo , Distrofias Hereditárias da Córnea/tratamento farmacológico , Humanos , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/patologia , Epitélio Pigmentado da Retina/efeitos dos fármacos , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Doenças Retinianas/genética , Doenças Retinianas/patologia , Doenças Retinianas/metabolismo , Doenças Retinianas/tratamento farmacológico , Família 4 do Citocromo P450/genética , Camundongos Endogâmicos C57BL , Linhagem Celular , Peroxidação de Lipídeos/efeitos dos fármacos
12.
Nano Lett ; 24(28): 8525-8534, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38954769

RESUMO

Cr2(NCN)3 is a potentially high-capacity and fast-charge Li-ion anode owing to its abundant and broad tunnels. However, high intrinsic chemical instability severely restricts its capacity output and electrochemical reversibility. Herein we report an effective crystalline engineering method for optimizing its phase and crystallinity. Systematic studies reveal the relevancy between electrochemical performance and crystalline structure; an optimal Cr2(NCN)3 with high phase purity and uniform crystallinity exhibits a high reversible capacity of 590 mAh g-1 and a stable cycling performance of 478 mAh g-1 after 500 cycles. In-operando heating XRD reveals its high thermodynamical stability over 600 °C, and in-operando electrochemical XRD proves its electrochemical Li storage mechanism, consisting of the primary Li-ion intercalation and subsequent conversion reactions. This study introduces a facile and low-cost method for fabricating high-purity Cr2(NCN)3, and it also confirms that the Li storage of Cr2(NCN)3 can be further improved by tuning its phase and crystallinity.

13.
Materials (Basel) ; 17(13)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38998149

RESUMO

A siliceous material in which a framework order was established with a surfactant with sixteen carbon atoms in alkyl chains, MCM-41-C16, was synthesised, surface-modified, and tested regarding the selected physical properties. The pristine material was extracted in an acidic aqueous alcohol and then lined with different surface groups. The properties of four adsorbents were investigated using XRD, X-ray photoelectron spectroscopy, and N2 physisorption techniques. The unit-cell constant was determined from X-ray diffractograms, being in fixed relation to the edge length of the hexagonal frame. The specific surface areas of mesopores and whole crystallites were determined from low-temperature N2-physisorption isotherms. The novelty of this work is a mathematical model of a crystalline microstructure explaining the sizes and shapes of crystalline grains in relation to adsorption features, proposed and successfully tested with the aforementioned experimental data. The roughness of the surface is different from one that is necessary to explain the experimental characteristics quantitatively.

14.
Natl Sci Rev ; 11(8): nwae189, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39007000

RESUMO

A major impediment to the development of the efficient use of artificial photosynthesis is the lack of highly selective and efficient photocatalysts toward the conversion of CO2 by sunlight energy at room temperature and ambient pressure. After many years of hard work, we finally completed the synthesis of graphdiyne-based palladium quantum dot catalysts containing high-density metal atom steps for selective artificial photosynthesis. The well-designed interface structure of the catalyst is composed of electron-donor and acceptor groups, resulting in the obvious incomplete charge-transfer phenomenon between graphdiyne and plasmonic metal nanostructures on the interface. These intrinsic characteristics are the origin of the high performance of the catalyst. Studies on its mechanism reveal that the synergism between 'hot electron' from local surface plasmon resonance and rapid photogenerated carrier separation at the ohmic contact interface accelerates the multi-electron reaction kinetics. The catalyst can selectively synthesize CH4 directly from CO2 and H2O with selectivity of near 100% at room temperature and pressure, and exhibits transformative performance, with an average CH4 yield of 26.2 µmol g-1 h-1 and remarkable long-term stability.

15.
Semin Ophthalmol ; : 1-7, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039754

RESUMO

BACKGROUND: The capsular tension ring is a novel assistant tool for cataract surgery; however, controversy exists in its co-implantation. The potential for hyperopic or myopic shift resulting from the co-implantation of the capsular tension ring and intraocular lens remains unclear. This study aimed to determine the postoperative refractive prediction error and the direction of refractive shift in cataract patients who underwent capsular tension ring co-implantation. METHODS: We conducted a systematic review and meta-analysis,searching electronic databases for studies of individuals diagnosed with cataracts receiving surgery with or without capsular tension ring implantation. Systematic searches were performed based on five databases: PubMed, Cochrane Library, Web of Science, Medline, and China National Knowledge Infrastructure. The primary outcome was the mean arithmetic refractive prediction error. Secondary outcomes were mean absolute refractive prediction error and the number of eyes within a certain refractive prediction error range. We applied a fixed-effectsmodel to pool effect sizes across trials using weighted mean differences (WMD) and risk ratios (RR) with their 95% confidence intervals (95% CI). Statistical heterogeneity scores were assessed with the I2statistic. RESULTS: A total of 407 affected eyes were included in eight independent clinical studies. Meta-analysis suggested significant differences both in short-term (≤1 month) co-implantation (WMD = 0.16, p < .001, 95% CI: -0.13 ~ 0.19) and long-term (≥3 months) co-implantation between the capsular tension ring co-implantation group and the control group (WMD = 0.19, p < .001, 95% CI: 0.15 ~ 0.23). However, no significant difference was observed in the high myopia subgroup whether capsular tension ring co-implantation (WMD = 0.03, p = .083, 95% CI: -0.27 ~ 0.34). Heterogeneity was not found among the studies. CONCLUSION: Compared to simple intraocular lens implantation, capsular tension ring co-implantation is more susceptible to developing hyperopic shifts in non-myopic cataract patients, probably related to anterior chamber depth. It requires careful consideration by clinicians when determining the target diopter preoperatively. However, interpretation is limited, because there is a lack of studies available for analysis. There still needs to be additional studies to expand the evidence base.

16.
Theriogenology ; 226: 328-334, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38959843

RESUMO

The objective of this study was to compare the plasma (PL) and seminal plasma (SP) pharmacokinetic profile of ceftiofur (CEFT) and desuroylceftiofur acetamide (DFCA) after administration of CEFT crystalline-free acid (CCFA) by SC route in two sites of the ear in beef bulls. Four clinically healthy Hereford bulls received a comprehensive physical exam and subsequently a breeding-soundness examination, CBC, and chemistry profile panel. All bulls were diagnosed healthy and satisfactory potential breeders. In one group (n = 2), a single dose of CCFA was administered SC route at the base of the ear (BOE) at a dose of 6.6 mg/kg of body weight. The second group (n = 2) was also administered by SC route in the middle third of the posterior aspect of the ear (MTE). The concentrations of CEFT and DFCA in PL and SP were determined by a high-performance liquid chromatography mass spectrometry (HPLC-MS). Blood and semen samples were collected before the administration of CCFA and at 12, 24, 36, 48, 72, 96, 120, 144, and 168 h after injection. No levels of CEFT were detected in PL and only in 20 of the 40 SP samples (P = 0.0001). The mean level of CEFT in SP was 0.11 % in comparison with the DFCA level. DFCA was found in all PL and SP samples. Therefore, DFCA was chosen to be utilized in the study of the pharmacokinetics parameters both in PL and SP. There were no differences in the mean PL levels of DFCA for the two sites of SC administration between the BOE (102.9 ± 78.9 ng/mL; X ± SD) and to MTE (116.1 ± 70.2 ng/mL; P = 0.58). The mean SP levels of DFCA after administration in the BOE was 857 ± 747 ng/mL, and for the MTE was 549 ± 488 ng/mL without differences between both sites (P = 0.15). The mean level of DFCA in PL was 109.5 ± 74.0 ng/mL, which was lower than the mean SP levels of 695 ± 103 ng/mL (P = 0.001). Moreover, the PL peak DFCA concentration (Cmax) was 229 ± 46 ng/mL at 36.0 ± 29.4 h (Tmax) post-administration. The SP Cmax was 1851 ± 533 ng/mL at 30.0 ± 28.6 h (Tmax) post-administration. The Cmax between PL and SP were distinctive (P = 0.004) without any differences in Tmax between PL and SP (P = 0.60). The terminal half-life for PL DFCA (47.4 ± 29.3 h) was not different than in SP (53.1 ± 23.6 h; P = 0.77). The PL area under the curve concentration time from the first to the last sample (AUC0-last) was 18,984 ± 4841 ng/mL/h, which was significatively smaller compared with 125,677 ± 59,445 ng/mL/h for SP AUC0-last (P = 0.04). The PL mean residence time from the first to the last sample (MRT0-last) was 69.7 ± 15.1 h, and it was similar than for SP of 66.5 ± 7.7 h (P = 0.69). From the present investigation, based in its pharmacokinetic features, it was concluded that CCFA should be an appropriate antibiotic that could be used for the treatment of bull genital infections when its indication is properly outlined. To study the pharmacokinetics of CCFA in SP, DFCA metabolite was appropriated.


Assuntos
Antibacterianos , Cefalosporinas , Sêmen , Animais , Masculino , Bovinos , Cefalosporinas/farmacocinética , Cefalosporinas/sangue , Cefalosporinas/administração & dosagem , Sêmen/química , Antibacterianos/farmacocinética , Antibacterianos/sangue , Antibacterianos/administração & dosagem
17.
Environ Sci Technol ; 58(29): 13110-13119, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38989600

RESUMO

Transition-metal dichalcogenides (TMDs) have shown great promise as selective and high-capacity sorbents for Hg(II) removal from water. Yet, their design should consider safe disposal of spent materials, particularly the subsequent formation of methylmercury (MeHg), a highly potent and bioaccumulative neurotoxin. Here, we show that microbial methylation of mercury bound to MoS2 nanosheets (a representative TMD material) is significant under anoxic conditions commonly encountered in landfills. Notably, the methylation potential is highly dependent on the phase compositions of MoS2. MeHg production was higher for 1T MoS2, as mercury bound to this phase primarily exists as surface complexes that are available for ligand exchange. In comparison, mercury on 2H MoS2 occurs largely in the form of precipitates, particularly monovalent mercury minerals (e.g., Hg2MoO4 and Hg2SO4) that are minimally bioavailable. Thus, even though 1T MoS2 is more effective in Hg(II) removal from aqueous solution due to its higher adsorption affinity and reductive ability, it poses a higher risk of MeHg formation after landfill disposal. These findings highlight the critical role of nanoscale surfaces in enriching heavy metals and subsequently regulating their bioavailability and risks and shed light on the safe design of heavy metal sorbent materials through surface structural modulation.


Assuntos
Mercúrio , Metilação , Adsorção , Nanoestruturas/química , Poluentes Químicos da Água/química , Compostos de Metilmercúrio , Molibdênio/química
18.
ACS Nano ; 18(28): 18444-18456, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38953611

RESUMO

Rechargeable aqueous batteries adopting Fe-based materials are attracting widespread attention by virtue of high-safety and low-cost. However, the present Fe-based anodes suffer from low electronic/ionic conductivity and unsatisfactory comprehensive performance, which greatly restrict their practicability. Concerning the principle of physical chemistry, fabricating electrodes that could simultaneously achieve ideal thermodynamics and fast kinetics is a promising issue. Herein, hierarchical Fe3O4@Fe foam electrode with enhanced interface/grain boundary engineering is fabricated through an in situ self-regulated strategy. The electrode achieves ultrahigh areal capacity of 31.45 mA h cm-2 (50 mA cm-2), good scale application potential (742.54 mA h for 25 cm2 electrode), satisfied antifluctuation capability, and excellent cycling stability. In/ex situ characterizations further validate the desired thermodynamic and kinetic properties of the electrode endowed with accurate interface regulation, which accounts for salient electrochemical reversibility in a two-stage phase transition and slight energy loss. This work offers a suitable strategy in designing high-performance Fe-based electrodes with comprehensive inherent characteristics for high-safety large-scale energy storage.

19.
Exp Eye Res ; 246: 109992, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38972445

RESUMO

Previous studies have shown that pharmaceutical agents such as lipoic acid have the ability to soften the lens, presenting a promising avenue for treating presbyopia. One obstacle encountered in the preclinical stage of such agents is the need for precise measurements of lens elasticity in experimental models. This study aimed to evaluate the effects of 25-hydroxycholesterol, lipoic acid, and obeticholic acid on the viscoelastic properties of mouse lenses using a custom-built elastometer system. Data were acquired on lenses from C57BL/6J female mice from two age groups: young (age: 8-10 weeks) and old (age: 32-43 weeks). OD lenses were used as the control and OS lenses were treated. Control lenses were immersed in Dulbecco's Modified Eagle Medium (DMEM) and treatment lenses were immersed in a compound solution containing 25-hydroxycholesterol (5 young and 5 old), lipoic acid at 2.35 mM (5 young and 5 old), lipoic acid at 0.66 mM (5 old), or obeticholic acid (5 old) at 37 °C for 18 h. After treatment, the mouse lenses were placed in a DMEM-filled chamber within a custom-built elastometer system that recorded the load and lens shape as the lens was compressed by 600 µm at a speed of 50 µm/s. The load was continuously recorded during compression and during stress-relaxation. The compression phase was fit with a linear function to quantify lens stiffness. The stress-relaxation phase was fit with a 3-term exponential relaxation model providing relaxation time constants (t1, t2, t3), and equilibrium load. The lens stiffness, time constants and equilibrium load were compared for the control and treated groups. Results revealed an increase in stiffness with age for the control group (young: 1.16 ± 0.11 g/mm, old: 1.29 ± 0.14 g/mm) and relaxation time constants decreased with age (young: t1 = 221.9 ± 29.0 s, t2 = 24.7 ± 3.8 s, t3 = 3.12 ± 0.87 s, old: t1 = 183.0 ± 22.0 s, t2 = 20.6 ± 2.6 s and t3 = 2.24 ± 0.43 s). Among the compounds tested, only 25-hydroxycholesterol produced statistically significant changes in the lens stiffness, relaxation time constants, and equilibrium load. In conclusion, older mouse lenses are stiffer and less viscous than young mouse lenses. Notably, no significant change in lens stiffness was observed following treatment with lipoic acid, contrary to previous findings.

20.
Appl Microbiol Biotechnol ; 108(1): 404, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953996

RESUMO

Polyethylene terephthalate (PET) is a major component of plastic waste. Enzymatic PET hydrolysis is the most ecofriendly recycling technology. The biorecycling of PET waste requires the complete depolymerization of PET to terephthalate and ethylene glycol. The history of enzymatic PET depolymerization has revealed two critical issues for the industrial depolymerization of PET: industrially available PET hydrolases and pretreatment of PET waste to make it susceptible to full enzymatic hydrolysis. As none of the wild-type enzymes can satisfy the requirements for industrialization, various mutational improvements have been performed, through classical technology to state-of-the-art computational/machine-learning technology. Recent engineering studies on PET hydrolases have brought a new insight that flexibility of the substrate-binding groove may improve the efficiency of PET hydrolysis while maintaining sufficient thermostability, although the previous studies focused only on enzymatic thermostability above the glass transition temperature of PET. Industrial biorecycling of PET waste is scheduled to be implemented, using micronized amorphous PET. Next stage must be the development of PET hydrolases that can efficiently degrade crystalline parts of PET and expansion of target PET materials, not only bottles but also textiles, packages, and microplastics. This review discusses the current status of PET hydrolases, their potential applications, and their profespectal goals. KEY POINTS: • PET hydrolases must be thermophilic, but their operation must be below 70 °C • Classical and state-of-the-art engineering approaches are useful for PET hydrolases • Enzyme activity on crystalline PET is most expected for future PET biorecycling.


Assuntos
Hidrolases , Polietilenotereftalatos , Polietilenotereftalatos/metabolismo , Polietilenotereftalatos/química , Hidrolases/metabolismo , Hidrolases/química , Hidrolases/genética , Hidrólise , Engenharia de Proteínas/métodos , Biodegradação Ambiental , Reciclagem
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