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1.
Front Pediatr ; 12: 1377061, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39328585

RESUMEN

Background: Differentiated thyroid cancer (DTC) has been increasingly common in women of reproductive age. However, the evidence remains mixed regarding the association of DTC with adverse pregnancy outcomes in pregnant women previously diagnosed with DTC. Methods: We conducted a retrospective cohort study in the Peking University Third Hospital in Beijing, China between January 2012 and December 2022. We included singleton-pregnancy women with a pre-pregnancy DTC managed by surgical treatment (after-surgery DTC) or active surveillance (under-surveillance DTC). To reduce the confounding effects, we adopted a propensity score to match the after-surgery and under-surveillance DTC groups with the non-DTC group, respectively, on age, parity, gravidity, pre-pregnancy weight, height, and Hashimoto's thyroiditis. We used conditional logistics regressions, separately for the after-surgery and under-surveillance DTC groups, to estimate the adjusted associations of DTC with both the composite of adverse pregnancy outcomes and the specific mother-, neonate-, and placenta-related pregnancy outcomes. Results: After the propensity-score matching, the DTC and non-DTC groups were comparable in the measured confounders. In the after-surgery DTC group (n = 204), the risk of the composite or specific adverse pregnancy outcomes was not significantly different from that of the matched, non-DTC groups (n = 816; P > 0.05), and the results showed no evidence of difference across different maternal thyroid dysfunctions, gestational thyrotropin levels, and other pre-specified subgroup variables. We observed broadly similar results in the under-surveillance DTC group (n = 37), except that the risk of preterm birth, preeclampsia, and delivering the low-birth-weight births was higher than that of the matched, non-DTC group [n = 148; OR (95% CI): 4.79 (1.31, 17.59); 4.00 (1.16, 13.82); 6.67 (1.59, 27.90)]. Conclusions: DTC was not associated with adverse pregnancy outcomes in pregnant women previously treated for DTC. However, more evidence is urgently needed for pregnant women with under-surveillance DTC, which finding will be clinically significant in individualizing prenatal care.

4.
Artículo en Inglés | MEDLINE | ID: mdl-38985335

RESUMEN

We assess the associations between personality traits and co-occurrence of depressive symptoms and high BMI from adolescence to early adulthood. We employed a nationally representative cohort in China from 2010 to 2020 year. We included adolescents aged 10-19 years without depressive symptoms and unhealthy weight status (obesity, overweight, or thinness) at baseline and excluded those without any measurement of depressive symptoms or BMI at follow-ups. We assessed baseline personality traits in 7 dimensions of conscientiousness, openness, neuroticism, agreeableness, extraversion, self-esteem, and responsibility. We also assessed the combined effects of these 7 dimensions of personality traits by generating individual-level personality trait risk scores based on the weighted sum of all these 7 dimensions of personality traits. We measured the co-occurrence of depressive symptoms and high BMI using both a single measurement of depressive symptoms and BMI at the last follow-up and repeated measurements of them over 10 years. We used the multinomial logistic regression models to examine the exposure-outcome associations. At baseline, we included 1778 individuals (mean age: 14.4 year; female: 853 (48.0%)). At follow-ups, we observed increased risk of co-occurrence of depressive symptoms and high BMI per 1-SD increase in neuroticism score (1.95-2.38 odds ratio) or 1-SD decrease in self-esteem and conscientiousness (0.63-0.80 odds ratio; all P values < 0.05); we observed no evidence of associations between openness, agreeableness, extraversion, or responsibility and the risk of co-occurrence of depressive symptoms and high BMI (all P values > 0.05). For the combined effects of the 7 dimensions of personality traits, we found an elevated risk of co-occurrence of depressive symptoms and high BMI per 1-SD increase in the personality trait risk scores (OR (95% CI), single measurement at the last follow-up: 2.01, 1.66 to 2.43; trajectory classification using the repeated measurements 2.30, 1.55 to 3.42; average level using the repeated measurements: 2.27, 1.93 to 2.67). In this national cohort in China, personality traits were found to be associated with the co-occurrence of depressive symptoms and high BMI from adolescence to early adulthood. These findings highlight the importance of stratifying individuals based on their personality traits and providing targeted interventions for those at risk of comorbid depression and obesity.

5.
ISA Trans ; 152: 256-268, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39013690

RESUMEN

This study discusses a finite-time compensation tracking control method for a rehabilitative training walker. The dynamic model with input dead zone was constructed to describe the walker, and a finite-time disturbance forces observation method was proposed based on the impact mechanism on tracking performance. This approach is novel in that the disturbance forces were observed in reverse through their effects on tracking performance, thus successfully obtaining the disturbance forces of the walker. To ensure the practical finite-time stability of the system, the nonlinear finite-time compensation tracking controller with stochastic configuration networks (SCN) dead-zone estimation was built for the rehabilitative walker. Simulation results and comparative analyses confirmed that the proposed compensation control method effectively restrains dead zone and internal disturbance forces.

6.
Beijing Da Xue Xue Bao Yi Xue Ban ; 56(3): 397-402, 2024 Jun 18.
Artículo en Chino | MEDLINE | ID: mdl-38864123

RESUMEN

OBJECTIVE: To explore the association between self-control and the co-occurrence of depressive symptoms and overweight or obesity from adolescence to early adulthood in the Chinese population, and to provide a scientific basis for personalized interventions targeting individuals with different risks in the future. METHODS: From a prospective cohort study that lasted for 10 years: The China family panel studies (CFPS), a total of 608 children and adolescents meeting the following inclusion and exclusion criteria were included as study subjects: (1) Aged 10 to 19 years, at normal weight according to Chinese standards, and without depressive symptom in 2010; (2) Had self-control scores, and with at least two measurements of depressive symptoms and body mass index (BMI) between 2010 and 2020; (3) The only one or the youngest child and adolescent from each family. The co-occurrence of depressive symptoms and overweight or obesity was defined in three ways: Both of the average level of standardized scores of depressive symptoms and BMI Z-scores across multiple measurements over time were at a high level, or both of the trajectories of depressive symptoms and BMI over time based on the latent classification trajectory model (LCTM) belonging to the "risk-type", or individuals had depressive symptoms and overweight/obesity at the last follow-up survey. The multinomial Logistic regression model was used to examine the association between standardized scores of self-control and the co-occurrence of depressive symptoms and overweight or obesity. RESULTS: The score of self-control was associated with the co-occurrence of depressive symptoms and overweight or obesity when using healthy individuals as the reference group after adjusting for age (years), gender (male/female), area (urban/rural), weekly physical activity duration (high/low), parental education level (college or above/high school or below), parental weight status (overweight or obese or not), and parental depressive symptoms (with depressive symptoms or not), regardless of the definition of the risk population. Specifically, the risk of co-occurrence of depressive symptoms and overweight or obesity was reduced by 33% (95%CI: 14% to 48%, based on the average level across multiple measurements over time) to 78% (95%CI: 6% to 95%, based on the joint trajectories of depressive symptoms and BMI over time) per 1-standard deviation (1-SD) increase in self-control score. In addition, the risk of depressive-symptom-dominant and overweight-or-obesity-dominant was reduced by 25% (95%CI: 4% to 42%, only based on the average level across multiple measurements over time) and 21% (95%CI: 1% to 37%, only based on the joint trajectories of depressive symptoms and BMI over time) per 1-SD increase in self-control score, respectively. The results from sensitivity analysis that defined individuals' weight status according to World Health Organization (WHO) standards were consistent with our main findings. CONCLUSION: Individuals with higher self-control scores from adolescence to early adulthood have a lower risk of co-occurrence of depressive symptoms and overweight or obesity, suggesting that personalized interventions for co-occurrence of depressive symptoms and overweight or obesity can be carried out based on self-control scores in the future.


Asunto(s)
Índice de Masa Corporal , Depresión , Obesidad , Sobrepeso , Autocontrol , Humanos , Adolescente , Estudios Prospectivos , Depresión/epidemiología , Femenino , Masculino , Sobrepeso/epidemiología , Sobrepeso/psicología , China/epidemiología , Obesidad/epidemiología , Obesidad/psicología , Obesidad/complicaciones , Niño , Adulto Joven , Encuestas y Cuestionarios , Estudios de Cohortes
7.
Front Cardiovasc Med ; 11: 1372055, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38699583

RESUMEN

Inflammation and dyslipidemia are critical inducing factors of atherosclerosis. Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors and control the expression of multiple genes that are involved in lipid metabolism and inflammatory responses. However, synthesized PPAR agonists exhibit contrary therapeutic effects and various side effects in atherosclerosis therapy. Natural products are structural diversity and have a good safety. Recent studies find that natural herbs and compounds exhibit attractive therapeutic effects on atherosclerosis by alleviating hyperlipidemia and inflammation through modulation of PPARs. Importantly, the preparation of natural products generally causes significantly lower environmental pollution compared to that of synthesized chemical compounds. Therefore, it is interesting to discover novel PPAR modulator and develop alternative strategies for atherosclerosis therapy based on natural herbs and compounds. This article reviews recent findings, mainly from the year of 2020 to present, about the roles of natural herbs and compounds in regulation of PPARs and their therapeutic effects on atherosclerosis. This article provides alternative strategies and theoretical basis for atherosclerosis therapy using natural herbs and compounds by targeting PPARs, and offers valuable information for researchers that are interested in developing novel PPAR modulators.

8.
Obes Rev ; 25(5): e13715, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38320834

RESUMEN

Numerous guidelines have called for personalized interventions to address childhood obesity. The role of fat mass and obesity-associated gene (FTO) in the risk of childhood obesity has been summarized. However, it remains unclear whether FTO could influence individual responses to obesity interventions, especially in children. To address this, we systematically reviewed 12,255 records across 10 databases/registers and included 13 lifestyle-based obesity interventions (3980 children with overweight/obesity) reporting changes in body mass index (BMI) Z-score, BMI, waist circumference, waist-to-hip ratio, and body fat percentage after interventions. These obesity-related outcomes were first compared between children carrying different FTO genotypes (rs9939609 or its proxy) and then synthesized by random-effect meta-analysis models. The results from single-group interventions showed no evidence of associations between FTO risk allele and changes in obesity-related outcomes after interventions (e.g., BMI Z-score: -0.01; 95% CI: -0.04, 0.01). The results from controlled trials showed that associations between the FTO risk allele and changes in obesity-related outcomes did not differ by intervention/control group. To conclude, the FTO risk allele might play a minor role in the response to obesity interventions among children. Future studies might pay more attention to the accumulation effect of multiple genes in the intervention process among children.


Asunto(s)
Obesidad Infantil , Niño , Humanos , Índice de Masa Corporal , Predisposición Genética a la Enfermedad , Genotipo , Obesidad Infantil/genética , Obesidad Infantil/prevención & control , Pérdida de Peso
9.
Chin Med J (Engl) ; 137(5): 547-555, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38311812

RESUMEN

BACKGROUND: Differentiated thyroid cancer (DTC) is commonly diagnosed in women of child-bearing age, but whether pregnancy influences the prognosis of DTC remains controversial. This study aimed to summarize existing evidence regarding the association of pregnancy with recurrence risk in patients previously treated for DTC. METHODS: We searched PubMed, Embase, Web of Science, Cochrane, and Scopus based on the prespecified protocol registered at PROSPERO (CRD42022367896). After study selection, two researchers independently extracted data from the included studies. For quantitative data synthesis, we used random-effects meta-analysis models to pool the proportion of recurrence (for pregnant women only) and odds ratio (OR; comparing the risk of recurrence between the pregnancy group and the nonpregnancy group), respectively. Then we conducted subgroup analyses to explore whether risk of recurrence differed by response to therapy status or duration of follow-up time. We also assessed quality of the included studies. RESULTS: A total of ten studies were included. The sample size ranged from 8 to 235, with participants' age at pregnancy or delivery ranging from 28 to 35 years. The follow-up time varied from 0.1 to 36.0 years. The pooled proportion of recurrence in all pregnant patients was 0.13 (95% confidence intervals [CI]: 0.06-0.25; I2 : 0.58). Among six included studies reporting response to therapy status before pregnancy, we observed a trend for increasingly higher risk of recurrence from excellent, indeterminate, and biochemically incomplete to structurally incomplete response to therapy ( Ptrend <0.05). The pooled risk of recurrence in the pregnancy group showed no evidence of a significant difference from that in the nonpregnancy group (OR: 0.75; 95% CI: 0.45-1.23; I2 : 0). The difference in follow-up time (below/above five years) was not associated with either the proportion of recurrence in all pregnant patients ( P >0.05) or the OR of recurrence in studies with a comparison group ( P >0.05). Two included studies that focused on patients with distant metastasis also did not show a significant difference in disease recurrence between pregnancy and nonpregnancy groups (OR: 0.51 [95% CI: 0.14-1.87; I2 : 59%]). CONCLUSION: In general, pregnancy appears to have a minimal association with the disease recurrence of DTC with initial treatment. Clinicians should pay more attention to progression of DTC among pregnant women with biochemical and/or structural persistence. REGISTRATION: PROSPERO, https://www.crd.york.ac.uk/PROSPERO/ ; No. CRD42022367896.


Asunto(s)
Recurrencia Local de Neoplasia , Neoplasias de la Tiroides , Humanos , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/terapia , Embarazo , Femenino , Complicaciones Neoplásicas del Embarazo/patología , Complicaciones Neoplásicas del Embarazo/terapia
10.
J Clin Endocrinol Metab ; 109(3): 837-843, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-37738427

RESUMEN

CONTEXT AND OBJECTIVE: Differentiated thyroid cancer (DTC) is very common in women of reproductive age. However, it remains unclear whether pregnancy is associated with DTC progression before surgical treatment. METHODS: This retrospective cohort study, conducted at the Peking University Third Hospital in Beijing, China between January 2012 and December 2022, included 311 eligible women aged 20 to 45 years. To control for potential confounders, we first used propensity score matching (PSM) to match the pregnant group (n = 48) with the nonpregnant group (n = 154) on age, tumor size, tumor type, and Hashimoto's thyroiditis status at baseline, and then used Cox proportional risk models stratified by the matched pairs to estimate the association of pregnancy with DTC progression. RESULTS: After PSM, the pregnant and nonpregnant groups were well comparable at baseline (standardized difference < 10% and P > .05). Over an average observation period of 2.5 years, we observed no difference between the pregnant group and the matched nonpregnant group in DTC progression-free survival (hazard ratio [HR] = 0.96; 95% CI, 0.56 to 1.65; P = .895), tumor enlargement-free survival (HR = 0.99; 95% CI, 0.56 to 1.76; P = .969) or lymph node metastasis-free survival (LNM) (HR = 0.67; 95% CI, 0.21 to 2.13; P = .498). The postoperative pathological characteristics also showed no significant difference between the pregnant and nonpregnant groups (P > .05). CONCLUSION: Pregnancy seemed to be irrelevant to DTC progression-free survival before surgical treatment. Further prospective cohort studies are needed to translate this finding into clinical practice.


Asunto(s)
Adenocarcinoma , Enfermedad de Hashimoto , Neoplasias de la Tiroides , Embarazo , Humanos , Femenino , Estudios Retrospectivos , Puntaje de Propensión , Neoplasias de la Tiroides/epidemiología , Neoplasias de la Tiroides/cirugía , Neoplasias de la Tiroides/patología
11.
Technol Health Care ; 32(2): 823-830, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37393459

RESUMEN

BACKGROUND: In malignant tumours of the female reproductive system, cervical cancer is second only to breast cancer, seriously threatening the health and safety of most women. OBJECTIVE: To evaluate the clinical value of 3.0 T multimodal nuclear magnetic resonance imaging (MRI) in the International Federation of Gynecology and Obstetrics' (FIGO) staging of cervical cancer. METHODS: The clinical data of 30 patients with pathologically diagnosed cervical cancer admitted to our hospital from January 2018 to August 2022 were analysed retrospectively. Before treatment, all patients were examined with conventional MRI, diffusion-weighted imaging and multi-directional contrast-enhanced imaging. RESULTS: The accuracy of multimodal MRI in the FIGO staging of cervical cancer (29/30, 96.7%) was significantly higher than the accuracy obtained in a control group (21/30, 70.0%), with a statistically significant difference (p= 0.013). In addition, there was good agreement between two observers applying multimodal imaging (kappa= 0.881) and moderate agreement between two observers in the control group (kappa= 0.538). CONCLUSION: Multimodal MRI can evaluate cervical cancer comprehensively and accurately to enable accurate FIGO staging, providing significant evidence for clinical operation planning and subsequent combined therapy.


Asunto(s)
Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/diagnóstico por imagen , Estadificación de Neoplasias , Estudios Retrospectivos , Imagen por Resonancia Magnética/métodos , Imagen de Difusión por Resonancia Magnética
12.
Clin Nutr ; 43(1): 163-175, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38052139

RESUMEN

BACKGROUND: Multiple lifestyle-based childhood obesity interventions have been conducted to address childhood obesity, but individual's response to the universal intervention approach varied greatly. Whether gene variants related to children and adolescents' varied responses to obesity interventions remained unclear. AIMS: To determine the associations of gene variants with the changes in obesity- and metabolism-related indicators after obesity interventions in children and adolescents. METHODS: Ten databases and registers (including grey literature) were searched. The lifestyle-based obesity interventions in children and adolescents (≤18 years) that reported the changes in obesity- (body mass index (BMI), BMI Z-score, waist circumference (WC), waist-to-hip ratio (WHR), etc) and metabolism-related (glucose, cholesterol, etc) indicators by genotype after interventions were included. Our primary outcome was the mean difference of the changes in BMI Z-score by genotype after interventions, and secondary outcomes were changes in the remaining obesity- and metabolism-related indicators after interventions. We used the random-effects model to synthesize the results. RESULTS: This review included 50 studies (15,354 children and adolescents with overweight/obesity) covering 102 genes and 174 single nucleotide polymorphisms (SNPs). Approximately three-quarters of SNPs showed no evidence of association with the changes in obesity- or metabolic-related indicators after interventions. One quarter of SNPs were minorly associated with the changes in the BMI Z-score (median effect size: 0.001) with little clinical significance. Only 6 (12 %) studies focused on the accumulated effect of multiple gene variants. CONCLUSIONS: Gene variants that have been explored appear to play a minor role in lifestyle-based obesity interventions in children and adolescents. More high-quality studies based on the design of randomized controlled trials are needed to examine the accumulated effect of multiple gene variants in childhood obesity interventions. PROSPERO REGISTRY NUMBER: This systematic review and meta-analysis was registered at PROSPERO as CRD42022312177.


Asunto(s)
Obesidad Infantil , Adolescente , Niño , Humanos , Obesidad Infantil/genética , Obesidad Infantil/terapia , Sobrepeso , Índice de Masa Corporal , Estilo de Vida
13.
Sci Total Environ ; 913: 169535, 2024 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-38159752

RESUMEN

Pyrolysis technology is considered one of the most promising processes for the environmentally friendly disposal of sewage sludge (SS), as it can neutralize pathogens, reduce hazardous substances, and promote the immobilization of heavy metals. However, nitrogen-containing gases produced in SS pyrolysis can be converted to nitrogen oxides, causing serious environmental pollution. In this study, we investigated the evolution of the nitrogen (N) element in rapid pyrolysis of SS and explored the effect of clay minerals (attapulgite, montmorillonite, and kaolin) in regulating N conversion. The results showed that the higher temperature (800 °C) could promote the conversion of pyrroles/pyridines and NOx precursors in char to N2 (the conversion rate was 32.76 %), and clay minerals catalyzed the cleavage of N-containing macromolecules in the bio-oil, reducing the N content in bio-oil from 28.70 % to 6.23 %, and was conducted to realize the denitrification of bio-oil. Notably, the attapulgite (ATP) on N migration was more effective and could reduce the yield of NOx precursors from 23.80 % to 10.55 % by capturing NH4* and inhibiting the secondary reaction, while catalyzing the removal of N2 from pyridine/pyrrole (N2 production increased to 34.38 %). MgO and CaO in the clays played a major role in facilitating the conversion of char-N to N2, and clay structures loading on the biochar surface promoted the catalysis of N-containing volatiles to N2 by metal oxides. This study provides a viable and harmless approach to SS minimization.

14.
Front Microbiol ; 14: 1287802, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38149271

RESUMEN

Due to its traditional fermentation, there are obvious limits on the quality improvements in black tea. However, microbial fermentation can provide an abundance of metabolites and improve the flavor of tea. The "golden flower" fungi are widely used in the microbial fermentation of tea and has unique uses in healthcare. To further explore the improvements in black tea quality achieved via microbial fermentation, we used widely targeted metabolomics and metagenomics analyses to investigate the changes in and effects of metabolites and other microorganisms during the interaction between the "golden flower" fungi and black tea. Five key flavor metabolites were detected, the levels of catechin, epigallocatechin gallate, (-)-epicatechin gallate were decreased by different degrees after the inoculation of the "golden flower" fungus, whereas the levels of caffeine and (+)-gallocatechin increased. Botryosphaeriaceae, Botryosphaeriales, Dothideomycetes, Aspergillaceae, Trichocomaceae, and Lecanoromycetes play a positive role in the black tea fermentation process after inoculation with the "golden flower" fungi. D-Ribose can prevent hypoxia-induced apoptosis in cardiac cells, and it shows a strong correlation with Botryosphaeriaceae and Botryosphaeriales. The interaction between microorganisms and metabolites is manifested in tryptophan metabolism, starch and sucrose metabolism, and amino sugar and nucleotide sugar metabolism. In conclusion, the changes in metabolites observed during the fermentation of black tea by "golden flower" fungi are beneficial to human health. This conclusion extends the knowledge of the interaction between the "golden flower" fungi and black tea, and it provides important information for improving the quality of black tea.

15.
ACS Omega ; 8(40): 37622, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37841196

RESUMEN

[This corrects the article DOI: 10.1021/acsomega.2c07909.].

16.
J Med Chem ; 66(19): 13746-13767, 2023 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-37791640

RESUMEN

Metallo-ß-lactamases (MBLs) are zinc-dependent enzymes capable of hydrolyzing all bicyclic ß-lactam antibiotics, posing a great threat to public health. However, there are currently no clinically approved MBL inhibitors. Despite variations in their active sites, MBLs share a common catalytic mechanism with carbapenems, forming similar reaction species and hydrolysates. We here report the development of 2-aminothiazole-4-carboxylic acids (AtCs) as broad-spectrum MBL inhibitors by mimicking the anchor pharmacophore features of carbapenem hydrolysate binding. Several AtCs manifested potent activity against B1, B2, and B3 MBLs. Crystallographic analyses revealed a common binding mode of AtCs with B1, B2, and B3 MBLs, resembling binding observed in the MBL-carbapenem product complexes. AtCs restored Meropenem activity against MBL-producing isolates. In the murine sepsis model, AtCs exhibited favorable synergistic efficacy with Meropenem, along with acceptable pharmacokinetics and safety profiles. This work offers promising lead compounds and a structural basis for the development of potential drug candidates to combat MBL-mediated antimicrobial resistance.


Asunto(s)
Carbapenémicos , Inhibidores de beta-Lactamasas , Animales , Ratones , Inhibidores de beta-Lactamasas/farmacología , Inhibidores de beta-Lactamasas/química , Carbapenémicos/farmacología , Meropenem/farmacología , Ácidos Carboxílicos , beta-Lactamasas/metabolismo , Antibacterianos/farmacología , Antibacterianos/química
17.
ACS Omega ; 8(37): 33349-33357, 2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37744794

RESUMEN

Adsorption and degradation of organic compounds on sludge were investigated by comparing activated and inactivated sludge at various dosages, pH values, and temperatures. The organic compounds in wastewater were identified and evaluated through fluorescence spectra. The results show that optimum adsorption occurred as the activated and inactivated sludge concentration was 4000 mg/L at a pH of 7.99 and a temperature of 30 °C. The fluorescence scanning spectrum indicated that activated sludge could remove protein-like organic matter, fulvic acid-like organic matter, and humic acid-like organic matter by 22.1, 9.4, and 41.2%, respectively, via adsorption only or by 25.9, 9.8, and 74.3%, respectively, via adsorption and degradation. Under optimum conditions, by using the good adsorption performance of sludge combined with other sewage treatment technologies, the treatment of high-content organic wastewater can be achieved.

18.
Waste Manag ; 171: 382-392, 2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37776809

RESUMEN

To relieve the secondary contamination of heavy metals (HMs), the synergistic effect of co-pyrolysis of textile dyeing sludge (DS)/litchi shell (LS) and CaO on the migration of HMs was demonstrated in this study. The proportions of Cu, Zn, Cr, Mn, and Ni in the F4 fraction increased to 75%, 55%, 100%, 50%, and 62% at the suitable CaO dosages. When 10% CaO was added, the RI value of DLC-10% was reduced to 7.89, indicating low environmental risk. The characterizations of the physicochemical properties of biochar provided support for the HMs immobilization mechanism. HMs combined with inorganic minerals or functional groups to form new stable HMs crystalline minerals and complexes to achieve immobilization of HMs. The pH value and pore structure also play an important role in improving the immobilization performance of HMs. In conclusion, the results provided a new direction for the subsequent harmless treatment of HMs-enriched waste.

19.
Chemosphere ; 342: 140205, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37722535

RESUMEN

An innovative Fe-N co-coupled catalyst MN-2 was prepared from waste spirulina by co-pyrolysis as a highly active carbon-based catalyst for the activation of peroxydisulfate (PDS) for the degradation of sulfathiazole (ST). The protein-rich raw material Spirulina provided sufficient N during the pyrolysis process, thus achieving N doping without an additional nitrogen source, optimizing the interlayer structure of the biochar material and effectively inhibiting the leaching of the ligand metal Fe. MN-2 showed highly efficient catalytic activity for peroxydisulfate (PDS), with a degradation efficiency of 100% for ST within 30 min and a kinetic constant (kobs) reached 0.306 min-1, benefiting from the excellent adsorption ability of MN-2 forming MN-2-PDS* complexes and the electron transfer process generated by Fe3+ and Fe2+ cycling, oxygen-containing functional groups. The effects of PDS dosage, initial pH and coexisting anions on the oxidation process were also investigated. Free radical quenching, electron paramagnetic resonance and electrochemical measurements were employed to explain the hydroxyl (·OH) and sulfate (SO4·-) as the dominant active species and the electron transfer effect on the removal of ST. MN-2 maintained a ST removal rate of 84% after four recycling experiments, showing a high reusability performance. This work provides a simple way to prepare magnetized N-doped biochar, a novel catalyst (MN-2) for efficient activation of PDS for ST degradation, and a feasible method for removing sulfanilamide antibiotics in water environment.


Asunto(s)
Carbón Orgánico , Electrones , Transporte de Electrón , Carbón Orgánico/química , Sulfatiazol
20.
iScience ; 26(7): 106967, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37534188

RESUMEN

As countries pursue power system decarbonization, a well-intentioned strategy being pursued in jurisdictions like China is the strict integration target, often in the form of a curtailment cap. The effects of these curtailment caps have not been systematically studied. Here, we evaluate the effects of these caps on the decarbonization of one provincial power system using a capacity expansion model. Results reveal that curtailment caps yield deleterious effects that do not align with the stated goals of these policies. Capping curtailment significantly increases storage capacity (+43% with a 5% curtailment cap) and reduces renewable capacity (-17%). Even with the increase in flexible storage capacity, the policy still jeopardizes power system reliability by increasing occurrences of over or under generation. It also suppresses power generation from hydropower and reduces energy storage utilization while increasing fossil fuel utilization. Capping curtailment increases economic costs (+6% with a 5% curtailment cap) and CO2 emissions (+7%).

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