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1.
Int J Biol Macromol ; : 132303, 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38744366

RESUMO

In order to solve ecological remediation issues for abandoned mines with steep slopes, a kind of hydrogels with high cohesion and water-retaining were designed by inorganic mineral skeleton combining with polymeric organic network cavities. This eco-friendly hydrogel (MFA/HA-g-p(AA-co-AM)) was prepared with acrylic acid (AA)-acrylamide (AM) as network, which was grafted with humic acids (HA) as network binding point reinforcement skeleton and polar functional group donors, KOH-modified fly ash (MFA) as internal supporter. The maximum water absorption capacities were 1960 g/g for distilled water, which followed the pseudo-second-order model. This super water absorption was attributed to the first stage of 62 % fast absorption due to the high specific surface area, pore volume and low osmotic pressure, moreover, the multiple hydrophilic functional groups and network structure swell contributed to 36 % of the second stage slow adsorption. In addition, the pore filling of water in mesoporous channels contributed the additional 2 % water retention on the third stage. The high saline-alkali resistance correlated with the electrostatic attraction with MFA and multiple interactions with oxygen-containing functional groups in organic components. MFA and HA also enhanced the shear strength and fertility retention properties. After 5 cycles of natural dehydration and reabsorption process, these excellent characteristics of reusability and water absorption capacity kept above 97 %. The application of 0.6 wt% MFA/HA-g-p(AA-co-AM) at 15° slope could improve the growth of ryegrass by approximately 45 %. This study provides an efficient and economic superabsorbent material for ecological restoration of abandoned mines with steep slopes.

2.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 42(1): 56-61, 2024 Feb 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38475951

RESUMO

OBJECTIVES: This study aimed to evaluate the influence of ceramic type and thickness on the masking ability and final aesthetic effects of chairside machinable all-ceramic crowns. METHODS: Six kinds from three types chairside machinable ceramic materials (IPS e.max CAD HT/MT/LT, IPS Empress LT, and VITA Suprinity HT/T) in shade A2 were fabricated to slice specimens into 1.0, 1.5, and 2.0 mm-thick sections (n=10). The color parameters of the specimens against black and white tiles and four resin substrates (A2, A4, B3, and C4 shade) were measured with a spectrophotometer. The translucency parameter (TP) was calculated using color parameters measured over standard white and black backgrounds. The color differences (ΔE) were calculated between there substrate shades (A4, B3, C4 ) and A2 shade (control group). Two-way analysis of variance (ANOVA) was performed on the TP values. The two va-riables were ceramic type and ceramic thickness. Three-way ANOVA was used to determine the effects of ceramic materials, ceramic thickness, and substrate shades on the ΔE values, followed by Tukey test for multiple comparisons (α=0.05). RESULTS: Ceramic type, ceramic thickness, and substrate shade significantly affected the ΔE values (P<0.001). The L* and b* values of the specimens increased with increasing ceramic thickness, except in substrate A2, whereas the ΔE values decreased. The color difference of all 1.0 mm-thick specimens or all specimens over the substrates C4 shade exceeded the clinically acceptable threshold (ΔE>3.3). CONCLUSIONS: The masking ability of chairside machinable all-ceramic crowns is influenced by ceramic type and thickness, and ceramic material. The thickness of ceramic less than 2.0 mm cannot mask the gray shade abutment.


Assuntos
Porcelana Dentária , Estética Dentária , Cor , Teste de Materiais , Cerâmica , Coroas
3.
Chemosphere ; 352: 141343, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38331269

RESUMO

Dimethyl phthalate (DMP) is widely used as plasticizer, and this kind of plastic industry wastewater is refractory due to the complex chemical structure and endocrine disrupting property. In order to effectively degrade and mineralize DMP contaminated wastewater, a heterogeneous UVC/VUV-Fenton catalyst system was designed with the amendment of targeted design catalyst Fe3O4@CM-ß-CD/rGO with core-shell like structure covered with loose convex folded lamellar. The optimum removal and mineralization efficiency of DMP were 98.6 % and 62.8 % in 30 min with 150 mg L-1 Fe3O4@CM-ß-CD/rGO and 8 mmol L-1 H2O2. This efficient and fast removal were attributed to a variety of photocatalytic oxidative active species •OH, •O2- and h+ with 59.6%, 29.1% and 9.9% contribution ratio, which mainly took effect on benzene ring open and side-chain fracture by oxidative, hydrolysis and hydrogen substitution determined by the rupture energy requirement from chemical bond in DMP. The target function of CM-ß-CD in catalyst controlled the photo-electron generation rate and shorten mass transfer distance by the cladding lamellar, moreover, rGO accelerated the redox between Fe (II) and Fe (III) and electron transfer. The catalytic recovery and removal to DMP kept above 90 % after five recycles. This study provided an excellent performance catalyst and an effective photo-Fenton approach and for the treatment of endocrine disrupting wastewater.


Assuntos
Peróxido de Hidrogênio , Ácidos Ftálicos , beta-Ciclodextrinas , Peróxido de Hidrogênio/química , Águas Residuárias , Catálise
4.
Environ Res ; 249: 118427, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38325780

RESUMO

Porous organic polymers (POPs) present superior adsorption performance to steroid endocrine disruptors. However, the effective recovery and high cost have been a big limitation for their large-scale applications. Herein, magnetic azo-linked porous polymers (Fe3O4@SiO2/ALP-p) were designed and prepared in a green synthesis approach using low-price materials from phloroglucinol and pararosaniline via a diazo-coupling reaction under standard temperature and pressure conditions, which embedded with Fe3O4@SiO2 nanoparticles to form three-dimensional interlayer network structure with flexible-rigid interweaving. The saturated adsorption capacity to bisphenol-A (BPA) was 485.09 mg/g at 298 K, which increased by 1.4 times compared with ALP-p of relatively smaller mass density. This enhanced adsorption was ascribed to increment from surface adsorption and pore filling with 2.3 times of specific surface area and 2.6 times of pore volume, although the total organic functional groups decreased with Fe3O4@SiO2 amendment. Also, the adsorption rate increased by about 1.1 and 1.5-fold due to enhancement in the initial stage of surface adsorption and subsequent stage pore diffusion, respectively. Moreover, this adsorbent could be used in broad pH (3.0-7.0) and salinity adaptability (<0.5 mol/L). The loss of adsorption capacity and magnetic recovery were lower than 1.1% and 0.8% in each operation cycle because of the flexible-rigid interweave. This excellent performance was contributed by synergistic effects from physisorption and chemisorption, such as pore filling, electrostatic attraction, π-π stacking, hydrogen bonding, and hydrophobic interaction. This study offered a cost-effective, high-performing, and ecologically friendly material along with a green preparation method.


Assuntos
Compostos Benzidrílicos , Fenóis , Polímeros , Poluentes Químicos da Água , Adsorção , Fenóis/química , Poluentes Químicos da Água/química , Porosidade , Polímeros/química , Compostos Benzidrílicos/química , Química Verde/métodos , Compostos Azo/química , Reciclagem/métodos , Purificação da Água/métodos
5.
Environ Res ; 238(Pt 1): 117160, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37717801

RESUMO

In order to design an optimal carbon peak and carbon neutralization pathway for the high-density building sector, a dynamic prediction model is established using system-dynamics coupled building life cycle carbon emission model (SD-BLCA) with consideration of future evolutionary trajectory and time constraints. The model is applied in Beijing using the SD-BLCA combined with scenario analysis and Monte Carlo methods to explore optimal trajectory for its building sector under 30-year timeframe. The results indicate that by increasing the proportion of renewable energy generation by 7% and retrofitting 60 million m2 of existing buildings, these two mature measures can offset the growth of carbon emissions and achieve the peak target by 2025. However, achieving carbon neutrality necessitates a shift from isolated technologies to a comprehensive net-zero emissions strategy. The study proposes a time roadmap that integrates a zero-carbon energy supply system and the carbon reduction measures of the whole life cycle. This strategy primarily relies on renewable sources to provide heat, power, and hydrogen, resulting in estimated reductions of 29.8 Mt, 28.1 Mt, and 0.7 Mt, respectively. Zero energy buildings, green buildings, and renovated buildings can reduce carbon emissions through their own energy-saving measures by 8.4, 18.2, and 11.8 kg/m2, respectively.


Assuntos
Dióxido de Carbono , Carbono , Pequim , Dióxido de Carbono/análise , Condições Sociais , China
6.
J Hazard Mater ; 452: 131302, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37031670

RESUMO

Biological dehalogenation degradation was an important detoxification method for the ecotoxicity and teratogenic toxicity of fluorocorticosteroids (FGCs). The functional strain Acinetobacter pittii C3 can effectively biodegrade and defluorinate to 1 mg/L Triamcinolone acetonide (TA), a representative FGCs, with 86 % and 79 % removal proportion in 168 h with the biodegradation and detoxification kinetic constant of 0.031/h and 0.016/h. The dehalogenation and degradation ability of strain C3 was related to its dehalogenation genomic characteristics, which manifested in the functional gene expression of dehalogenation, degradation, and toxicity tolerance. Three detoxification mechanisms were positively correlated with defluorination pathways through hydrolysis, oxidation, and reduction, which were regulated by the expression of the haloacid dehalogenase (HAD) gene (mupP, yrfG, and gph), oxygenase gene (dmpA and catA), and reductase gene (nrdAB and TgnAB). Hydrolysis defluorination was the most critical way for TA detoxification metabolism, which could rapidly generate low-toxicity metabolites and reduce toxic bioaccumulation due to hydrolytic dehalogenase-induced defluorination. The mechanism of hydrolytic defluorination was that the active pocket of hydrolytic dehalogenase was matched well with the spatial structure of TA under the adjustment of the hydrogen bond, and thus induced molecular recognition to promote the catalytic hydrolytic degradation of various amino acid residues. This work provided an effective bioremediation method and mechanism for improving defluorination and detoxification performance.


Assuntos
Acinetobacter , Hidrolases , Hidrólise , Hidrolases/metabolismo , Acinetobacter/genética , Acinetobacter/metabolismo , Oxirredução , Genômica
7.
J Environ Manage ; 323: 116070, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36113292

RESUMO

The quality of groundwater along rivers is greatly affected by long-term infiltration from surface water, especially reclaimed water-receiving rivers. To predict the degree of influence of contaminated river water on groundwater quality, the spatiotemporal distribution and migration evolution prediction of benzo[a]pyrene (B(a)P) was monitored and simulated by Hydrus-coupled Groundwater Modeling Systems (GMS) model in terms of reclaimed water-receiving Liangshui River. The prediction results indicated the goodness-of-fit of this coupled model, according to the model efficiency (E: 0.78-0.93), the mean absolute error (MAE: 0.01-0.32 m) and the root-mean-square error (RMSE: 0.06-0.35 m). The vertical infiltration rate of B(a)P in the vadose zone was 0.102 m-1, which was only 0.73% that of water. B(a)P penetrated the 16 m depth vadose zone for 63 years owing to the attenuation function of adsorption and biodegradation, with contribution ratios of 78.4% and 19.3%, respectively. However, once B(a)P intersects with groundwater, the migration of B(a)P is dominated by horizontal migration due to downward movement along the groundwater flow direction. The migration rate of B(a)P in groundwater was 6.65 m/y in the horizontal direction, which was 2.42 and 16.22 times higher than the dispersion rate in the longitudinal and vertical directions, respectively. The spatiotemporal distribution indicated that the B(a)P concentration decreased with the crow-fly distance from river with attenuation rate constants of 1.19 × 10-4, 3.05 × 10-4, and 3.67 × 10-3 m-1 over horizontal, longitudinal, and vertical direction, respectively, which were negatively correlated with migration rate. However, the B(a)P content increased over the extension of infiltration time with an accumulation rate of 7.3 × 10-2 d-1. The migration and accumulation of B(a)P induced potential health risks to groundwater-based drinking water safety, which resulted in the groundwater safety utilization range decreasing from 450 m, 283 m, and 20.1 m-583 m, 338 m, and 28.2 m far from the river over the horizontal, longitudinal, and vertical directions, respectively, 20 years later. This study provides a numerical modeling solution for the viable spatiotemporal evolution of B(a)P in groundwater and an effective decision-making tool for the safe utilization of groundwater as drinking water.


Assuntos
Água Potável , Água Subterrânea , Poluentes Químicos da Água , Benzo(a)pireno , China , Monitoramento Ambiental/métodos , Rios , Poluentes Químicos da Água/análise
8.
J Hazard Mater ; 436: 129284, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35739793

RESUMO

Defluorination is a key factor in reducing biologically accumulated carcinogenic and teratogenic toxicity of fluoroglucocorticoids (FGCs). To enhance defluorination efficiency, a highly efficient defluorination-degrading strain Acinetobacter. pittii C3 was isolated, and the promotion mechanism through humic acid (HA)-mediated biotransformation was investigated. Optimal biodegradation conditions for Acinetobacter sp. pittii C3 were pH of 7.0, temperature of 25 â„ƒ, and HA content of 5.5 mg/L, according to response surface methodology analysis. The attenuation rate constant and maximum defluorination percentage of triamcinolone acetonide (TA) in HA-mediated biotransformation system (HA-C3) were 3.99 × 10-2 and 96%, respectively, which were 2.22 and 1.24 times higher than those in the unitary C3 biodegradation system (U-C3), respectively. The major defluorination pathways included elimination, hydrolysis, and hydrogenation, with contributions of 24.5%, 32.4%, and 43.1%, respectively. The bio-reductive hydrodefluorination rate was enhanced by 1.89 times that of HA-mediated, while the other two defluorination pathways exhibited insignificant changes. HA, as the congeries of negatively charged microbes and hydrophobic TA, accelerates the electron transfer rate between Acinetobacter. pittii C3 and TA through the quinone groups. Furthermore, the mutual conversion between the functional groups of hydroxyl oxidation and ketone reduction of HA provided electron donors for TA reductive defluorination and hydrogenation and electron acceptors for TA oxidation. This study provides an effective strategy for FGC-enhanced detoxification using natural HA.


Assuntos
Acinetobacter , Substâncias Húmicas , Acinetobacter/metabolismo , Biodegradação Ambiental , Biotransformação
9.
Artigo em Inglês | MEDLINE | ID: mdl-29234438

RESUMO

BACKGROUND: Many previous studies have shown the potential therapeutic effect of acupuncture for metabolic syndrome (MetS). However, most of these studies were limited by short durations of observation and a lack of sham acupuncture as control. We designed a randomized controlled trial, used sham acupuncture as the control, and evaluated the efficacy over 12 weeks of treatment and 12 weeks of follow-up. METHODS/DESIGN: The study was designed as a multicentre, parallel-group, randomized, double-blinded trial. 40 patients were randomly assigned to two groups: treatment group (treated with acupuncture) and control group (treated with sham acupuncture). Outcomes were measured at 4, 8, and 12 weeks and 3 months after treatment. RESULTS: 33 participants (17 in acupuncture group and 16 in control group) completed the treatment and the follow-up. Decreases from baseline in mean waist circumference (WC) and weight at the end of treatment were 4.85 cm (95% CI [2.405,5.595]) and 4.00 kg (95% CI [1.6208,4.4498]) in acupuncture group and 1.62 cm and 1.64 kg in control group (P < 0.01). The changes in mean glycosylated haemoglobin (HbA1c), triglycerides (TG), total cholesterol (TC), and blood pressure in acupuncture group were greater than the changes in control group (P < 0.05, P < 0.01). CONCLUSION: Acupuncture decreases WC, HC, HbA1c, TG, and TC values and blood pressure in MetS.

10.
Chin J Integr Med ; 23(11): 864-870, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28116662

RESUMO

OBJECTIVE: To organize the clinical practice guidelines (CPGs) related to acupuncture included in the National Guideline Clearinghouse (NGC) to systematically summarize the diseases and disorders most commonly treated with acupuncture, the strength of recommendations for acupuncture and the quality of evidence. METHODS: The NGC database was systematically searched for guidelines that included acupuncture as an intervention. Two independent reviewers studied the summaries and the full texts of the guidelines and included guidelines based on the inclusion and exclusion criteria. Thirty-nine guidelines were collected with 80 recommendations. The Appraisal of Guidelines for Research and Evaluation (AGREE) II instrument was used to assess the quality of these guidelines. RESULTS: Of the 80 recommendations on acupuncture, 49 recommendations were clearly for acupuncture, 25 recommendations were against acupuncture and 6 recommendations did not indicate any clear recommendations, 37 recommendations were for painful diseases/disorders, and 12 recommendations were for non-painful diseases/disorders. Locomotor system disorders were the most common in the painful diseases/disorders category. Out of all the recommendations for acupuncture, most recommendations (87.76%) were weak in strength, and most of the evidence (40.84%) was of low quality. CONCLUSIONS: In the National Guideline Clearinghouse, the recommendations for acupuncture focus on painful diseases/disorders. The recommendations in the guidelines are not high in strength, and most of the evidence is moderate or low in quality.


Assuntos
Terapia por Acupuntura , Guias de Prática Clínica como Assunto , Terapia por Acupuntura/efeitos adversos , Humanos , Avaliação de Resultados em Cuidados de Saúde
11.
Trials ; 17(1): 305, 2016 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-27363578

RESUMO

BACKGROUND: Many previous studies have shown the potential therapeutic effect of acupuncture for allergic rhinitis. Most of these studies, however, were limited by the short duration of observations and lack of sham acupuncture as the control group. Our preliminary experiments showed that the use of a warm needling achieved a much more persistent effect in the treatment of allergic rhinitis (AR) compared with simple acupuncture therapy. Hence, we have designed a multicenter, randomized controlled trial (RCT) in which the first-line medication loratadine will be used as the control group, and the effect of warm needling therapy will be evaluated through long-term observation. METHODS/DESIGN: The trial is designed as a multicenter, parallel-group, randomized, single-blinded (outcome assessors), non-inferiority trial. A total of 98 patients with persistent AR will be randomly assigned into two groups. Patients in the treatment group will be treated with warm needling at GV14 and acupuncture at EX-HN3, ST2, LI20, EX-HN8, GV23, LU7, LU5 and LI4 three times a week, for a total of 4 weeks. Patients in the control group will be treated with oral loratadine 10 mg/day for 4 weeks. The primary outcome will be the change in the Total Nasal Symptom Score (TNSS) from baseline to that at 6 months after treatment during the follow-up period. The secondary outcomes will include the Total Non-nasal Symptom Score and the Rhinoconjunctivitis Quality of Life Questionnaire, changes in the TNSS from baseline to that at 2 and 4 weeks during treatment, and 3 months after treatment during the follow-up period. Outcomes will be measured at 2 and 4 weeks, and 3 and 6 months after treatment. Any side effects of treatment will be observed and recorded. DISCUSSION: We expect that the study results will provide evidence to determine the effects of warm needling compared with loratadine. Our final goal of the study is to evaluate the difference in the short-term and long-term effects between the two therapeutic methods, especially the long-term effect of warm needling. TRIAL REGISTRATION: ClinicalTrials.gov NCT02339714 . Registered on 14 January 2015.


Assuntos
Terapia por Acupuntura/instrumentação , Antialérgicos/uso terapêutico , Loratadina/uso terapêutico , Agulhas , Rinite Alérgica/terapia , Terapia por Acupuntura/efeitos adversos , Adolescente , Adulto , Antialérgicos/efeitos adversos , China , Protocolos Clínicos , Feminino , Temperatura Alta , Humanos , Loratadina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Projetos de Pesquisa , Rinite Alérgica/diagnóstico , Rinite Alérgica/psicologia , Método Simples-Cego , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
12.
Chin J Integr Med ; 2015 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-26597284

RESUMO

A clinical practice guideline of acupuncture for depression was compiled according to the grading of recommendations assessment, development and evaluation (GRADE) method, including the clinical characteristics, diagnosis, treatment and other information about depression, while several acupuncture treatments of depression, severe depression, depression after stroke were recommended.

13.
Artigo em Inglês | MEDLINE | ID: mdl-26495023

RESUMO

This study was performed to evaluate the effectiveness and safety of warm needling acupuncture at meridian-sinew sites based on the meridian-sinew theory in the treatment of hemiplegic shoulder pain (HSP) after stroke. In total, 124 subjects were randomized into a treatment group and control group. In the treatment group, warm needling therapy and acupuncture at meridian-sinew sites based on the meridian-sinew theory were performed. In the control group, usual care therapy was applied. The visual analog scale (VAS) score, range of motion (ROM), and Barthel index (BI) were used to evaluate treatment effectiveness. At 2 weeks of treatment, the VAS score, ROM, and BI had obviously changed from baseline in the two groups (P < 0.01). The changes in the VAS score and ROM in the treatment group were significantly greater than those in the control group (P < 0.01). At the 3-month follow-up after treatment, the changes in the treatment group were significantly greater than those in the control group (P < 0.01). This study indicates that warm needling therapy with acupuncture at meridian-sinew sites based on the meridian-sinew theory is effective for HSP.

14.
Zhongguo Zhen Jiu ; 35(10): 1065-8, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26790227

RESUMO

Based on entire literature retrieval about low back pain treated with acupuncture and moxibustion, Clinical Practice Guideline for Low Back Pain Treated with Acupuncture and Moxibustion was drafted according to method of evidence quality and recommended intensity grading system(GRADE). This article specificly introduces the aim and available diseases of the guideline. The principle and recommended plans are also detailedly explained.


Assuntos
Terapia por Acupuntura/normas , Dor Lombar/terapia , Moxibustão/normas , Terapia por Acupuntura/métodos , China , Humanos , Moxibustão/métodos , Guias de Prática Clínica como Assunto
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