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1.
Proc Natl Acad Sci U S A ; 121(23): e2400159121, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38814870

RESUMO

Lithium is an emerging strategic resource for modern energy transformation toward electrification and decarbonization. However, current mainstream direct lithium extraction technology via adsorption suffers from sluggish kinetics and intensive water usage, especially in arid/semiarid and cold salt-lake regions (natural land brines). Herein, an efficient proof-of-concept integrated solar microevaporator system is developed to realize synergetic solar-enhanced lithium recovery and water footprint management from hypersaline salt-lake brines. The 98% solar energy harvesting efficiency of the solar microevaporator system, elevating its local temperature, greatly promotes the endothermic Li+ extraction process and solar steam generation. Benefiting from the photothermal effect, enhanced water flux, and enriched local Li+ supply in nanoconfined space, a double-enhanced Li+ recovery capacity was delivered (increase from 12.4 to 28.7 mg g-1) under one sun, and adsorption kinetics rate (saturated within 6 h) also reached twice of that at 280 K (salt-lake temperature). Additionally, the self-assembly rotation feature endows the microevaporator system with distinct self-cleaning desalination ability, achieving near 100% water recovery from hypersaline brines for further self-sufficient Li+ elution. Outdoor comprehensive solar-powered experiment verified the feasibility of basically stable lithium recovery ability (>8 mg g-1) directly from natural hypersaline salt-lake brines with self-sustaining water recycling for Li+ elution (440 m3 water recovery per ton Li2CO3). This work offers an integrated solution for sustainable lithium recovery with near zero water/carbon consumption toward carbon neutrality.

2.
Cardiovasc Diabetol ; 23(1): 128, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622690

RESUMO

BACKGROUND: Compelling evidence suggests that calcium/phosphorus homeostasis-related parameters may be linked to diabetes mellitus and cardiovascular events. However, few studies have investigated the association of fibroblast growth factor 23 (FGF23), α-klotho and FGF23/α-klotho ratio with atherosclerosis in patients with type 2 diabetes mellitus (T2DM). OBJECTIVE: This study was designed to evaluate whether FGF23, α-klotho and FGF23/α-klotho ratio are associated with T2DM and further to explore the relationships between these three factors and atherosclerosis in Chinese patients with T2DM. METHODS: Serum FGF23 and α-klotho levels were measured via an enzyme-linked immunosorbent assay (ELISA) kit, and the carotid intima-media thickness (CIMT) was assessed via high-resolution color Doppler ultrasonography. The associations of serum FGF23, α-klotho and FGF23/α-klotho ratio with atherosclerosis in T2DM patients were evaluated using multivariable logistic regression models. RESULTS: This cross-sectional study involved 403 subjects (207 with T2DM and 196 without T2DM), 41.7% of the patients had atherosclerosis, and 67.2% of the carotid intima were thickened to a thickness greater than 0.9 mm. Compared with those in the lowest tertile, higher tertiles of FGF23 levels and FGF23/α-klotho ratio were positively associated with T2DM after adjusting for covariates, and serum α-klotho concentration was inversely correlated with T2DM (all P values < 0.01). Moreover, elevated serum FGF23 levels and FGF23/α-klotho ratio were positively associated with CIMT and carotid atherosclerosis in T2DM patients (all P values < 0.01). Further spline analysis similarly revealed linear dose‒response relationship (all P values < 0.01). And there was still significant differences in CIMT and carotid atherosclerosis between the highest group of α-klotho and the reference group in T2DM patients (P values = 0.05). CONCLUSIONS: T2DM was positively linearly related to serum FGF23 concentration and FGF23/α-klotho ratio, and negatively correlated with serum α-klotho concentration. Furthermore, both FGF23 and FGF23/α-klotho ratio were positively correlated with CIMT and atherosclerosis in T2DM patients, while α-klotho was inversely correlated with both CIMT and atherosclerosis, although the associations were not completely significant. Prospective exploration and potential mechanisms underlying these associations remain to be further elucidated.


Assuntos
Aterosclerose , Doenças das Artérias Carótidas , Diabetes Mellitus Tipo 2 , Humanos , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/etiologia , Espessura Intima-Media Carotídea , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Estudos Prospectivos , Fatores de Risco
3.
Mol Psychiatry ; 28(4): 1793-1801, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36690792

RESUMO

Long-term sequelae clustering phenotypes are important for precise health care management in COVID-19 survivors. We reported findings for 1000 survivors 20 months after diagnosis of COVID-19 in a community-based cohort in China. Sequelae symptoms were collected from a validated questionnaire covering 27 symptoms involved in five organ systems including self-reported physical condition, dyspnea, cognitive function and mental health. The generalized symptoms were reported with the highest rate (60.7%), followed by the mental (48.3%), cardiopulmonary (39.8%), neurological (37.1%; cognitive impairment, 15.6%), and digestive symptoms (19.1%). Four clusters were identified by latent class analysis: 44.9% no or mild group (cluster 1), 29.2% moderate group with mainly physical impairment (cluster 2), 9.6% moderate group with mainly cognitive and mental health impairment (cluster 3), and 16.3% severe group (cluster 4). Physical comorbidities or history of mental disorders, longer hospitalization periods and severe acute illness predicted severe group. For moderate group, adults less than 60 years, with physical comorbidities and severe acute illness were more likely to have physical symptoms, while adult women with longer hospitalization stays had increased risk of cognitive and mental health impairment. Overall, among more than half of community COVID-19 survivors who presented moderate or severe sequelae 20 months after recovery, three-tenth had physical vulnerability that may require physical therapy aiming to improve functioning, one-tenth mental or cognitive vulnerable cases need psychotherapy and cognitive rehabilitation, and one-sixth severe group needs multidisciplinary clinical management. The remaining half is free to clinical intervention. Our findings introduced an important framework to map numerous symptoms to precise classification of the clinical sequelae phenotype and provide information to guide future stratified recovery interventions.


Assuntos
COVID-19 , Disfunção Cognitiva , Humanos , Feminino , Estudos de Coortes , Doença Aguda , Disfunção Cognitiva/epidemiologia , Cognição
4.
Artigo em Inglês | MEDLINE | ID: mdl-38087123

RESUMO

PURPOSE: Mental disorders remain the leading causes of disability worldwide. We aimed to determine the burden and trends of mental disorders in China from 1990 to 2019. METHODS: The incidence, prevalence, and disability-adjusted life years (DALYs) of mental disorders at national level of China were examined by age, sex, and subcategories. Temporal trends in the age-standardized rates for incidence, prevalence, and DALYs were assessed by the average annual percentage change (AAPC). All estimates are presented as numbers and age-standardized rates, with 95% uncertainty intervals (UIs). RESULTS: The number of incident cases due to mental disorders increased from 42.90 million to 52.72 million, the number of prevalent cases increased from 132.63 million to 160.16 million, and the number of DALYs increased from 15.64 million to 20.29 million during 1990-2019. Decreasing trends were observed in the age-standardized rates for incidence, prevalence and DALYs. Anxiety and depressive disorders were more frequent in women, while ADHD, conduct disorder, and autism spectrum disorders were more common in men. Compared with 1990, the age-specific incidence rates were higher in individuals under 14 years and over 55 years, whereas rates were lower in those aged 15-49 years in 2019. CONCLUSION: The number of incident cases, prevalent cases, and DALYs due to mental disorders gradually increased in China from 1990 to 2019. Anxiety and depressive disorders were the leading causes of burden due to mental disorders, which affected women more than men. Mental disorders deserve greater attention in health policy decision making.

5.
BMC Psychiatry ; 22(1): 562, 2022 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-35996107

RESUMO

BACKGROUND: High-quality mental health services can improve outcomes for people with mental health problems and abate the burden of mental disorders. We sought to identify the challenges the country's mental health system currently faces and the human resource situation related to psychological services and to provide recommendations on how the mental health workforce situation could be addressed in China. METHODS: This study used a cross-sectional survey design. A web-based questionnaire approach and a convenience sampling method were adopted. It was carried out from September 2020 to January 2021 in China, and we finally included 3824 participants in the analysis. Descriptive statistical analysis of the characteristics of the study sample was performed. The risk factors for competence in psychological counseling/psychotherapy were assessed using multiple linear regression analysis. RESULTS: Workforce related to psychotherapy is scarce in China, especially in Western China and community mental health sectors. Psychiatrists (39.1%) and nurses (38.9%) were the main service providers of psychotherapy in psychiatric hospitals, and clinical psychologists (6.9%) and counsellors (5.0%) were seriously scarce in mental health care sectors. A total of 74.2% of respondents had no systematic psychological training, and 68.4 and 69.2% of them had no self-experience and professional supervision, respectively. Compared with clinical psychologists and counselors, psychiatrists and nurses had less training. Systematic psychological training (ß = - 0.88), self-experience (ß = - 0.59) and professional supervision (ß = - 1.26) significantly influenced psychotherapy capacity (P<0.001). CONCLUSIONS: Sustained effort will be required to provide a high-quality, equitably distributed psychotherapy workforce in China, despite challenges for community mental health sectors and western China being likely to continue for some time. Because mental illness is implicated in so many burgeoning social ills, addressing this shortfall could have wide-ranging benefits.


Assuntos
Serviços de Saúde Mental , China , Estudos Transversais , Atenção à Saúde , Humanos , Recursos Humanos
6.
Psychosom Med ; 83(4): 368-372, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33951724

RESUMO

OBJECTIVE: Infectious diseases can cause psychological changes in patients. This study aimed to evaluate the prevalence and related risk factors for anxiety and depression in patients with COVID-19. METHODS: A cross-sectional study was performed on patients with COVID-19 admitted to the Sino-French New City branch of Wuhan Tongji Hospital from January to February 2020. The Zung Self-Rating Anxiety and Depression Scales were used to evaluate the prevalence of anxiety and depression. Demographic, clinical, and sociological data were also collected. Multivariable logistic regression analysis was used to identify independent risk factors of anxiety and depression in patients with COVID-19. RESULTS: In the current study, 183 patients were enrolled (mean age = 53 ± 9 years; 41.1% women). The prevalences of anxiety and depression were 56.3% and 39.3%, respectively. Logistic regression analysis revealed that older age, female sex, being divorced or widowed, COVID-19 disease duration, renal disease, and depression were identified as independent risk factors for anxiety in patients with COVID-19. Factors that were associated with depression were female sex, being widowed, COVID-19 disease duration, and anxiety. CONCLUSIONS: This study demonstrates a high prevalence of anxiety and depression in patients with COVID-19 at the peak of the epidemic in Wuhan, China. The identification of demographic, clinical, and social factors may help identify health care professionals to provide psychological care as part of treatment for patients with COVID-19 and other life-threatening infectious diseases.


Assuntos
Ansiedade/epidemiologia , COVID-19/psicologia , Depressão/epidemiologia , Ansiedade/etiologia , COVID-19/complicações , China/epidemiologia , Estudos Transversais , Depressão/etiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prevalência , Escalas de Graduação Psiquiátrica , Fatores de Risco
7.
Langmuir ; 37(6): 2195-2204, 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33533622

RESUMO

Multi-yolk-shell MnO@mesoporous carbon (MnO@m-carbon) nanopomegranates, featuring MnO nanoparticles within cavities of m-carbon with internal space between the MnO nanoparticle and a cavity carbon shell, were subtly constructed. Moreover, the buffer space was well controlled by means of regulating the size of the cavity in m-carbon or the content of MnO. The results of electrochemical measurements demonstrated that MnO(10)@m-carbon(22) nanopomegranates (MnO nanoparticle, 15 nm; cavity size, 22 nm) had the best cycling and rate performance for lithium ion storage. The pomegranate-like MnO@m-carbon nanostructures have shown several advantages for their excellent performance: the nanocavity in m-carbon can restrict the growth and agglomeration of MnO nanoparticles; the well-interconnected mesoporous carbon matrix provides a "highway" for electrons and lithium ion transport; the voids between the MnO nanoparticle and cavity shell can alleviate the volume expansion.

8.
Foot Ankle Surg ; 23(1): 32-39, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28159040

RESUMO

Today, autogenous bone graft (ABG) is still considered as the gold standard for joint fusion. Recombinant human platelet-derived growth factor-BB (rhPDGF-BB) which is of chemotactic and mitogenic to mesenchymal stem cells and possesses outstanding osteogenetic potentials has been used for ankle and foot fusion in recent years. The goal of this article is to evaluate the safety and efficacy of rhPDGF-BB versus ABG in foot and ankle fusion. The PubMed MEDLINE, EMBASE, Web of Science, and Cochrane Library were systematic searched. Finally, three randomized controlled trials (RCTs) with 634 patients were enrolled in this study. Results of radiologic effectiveness which included CT and radiographic union rates revealed that there was no significant difference between rhPDGF-BB approach and ABG approach. Analysis of clinical results held the same outcomes expect that ABG group was superior in long-term Short Form-12 physical component scores. The pooled results also demonstrated that rhPDGF-BB was as safe as ABG in foot and ankle surgery. However, autograft harvesting procedure has some drawbacks such as donor-site pain and morbidity, additional operation time, blood loss, and scarring, which can be overcome by rhPDGF-BB. Thus, rhPDGF-BB is a viable alternative to autograft in foot and ankle fusion surgery. Yet, more high-quality RCTs with long-term follow-up are still required to make the final conclusion.


Assuntos
Indutores da Angiogênese/uso terapêutico , Articulação do Tornozelo , Artrodese , Transplante Ósseo , Artropatias/cirurgia , Proteínas Proto-Oncogênicas c-sis/uso terapêutico , Becaplermina , Humanos , Artropatias/diagnóstico , Artropatias/etiologia , Transplante Autólogo
9.
Environ Eng Sci ; 33(1): 25-34, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26909006

RESUMO

A nonintrusive digital imaging process was developed to study particle size distributions created through flocculation and sedimentation. Quantification of particle size distributions under different operating conditions can be of use in the understanding of aggregation mechanisms. This process was calibrated by measuring standardized polystyrene particles of known size and was utilized to count and measure individual kaolin clay particles as well as aggregates formed by coagulation with polyaluminum chloride and flocculation. Identification of out-of-focus flocs was automated with LabVIEW and used to remove them from the database that was analyzed. The particle diameter of the test suspension of kaolinite clay was measured to be 7.7 ± 3.8 µm and a linear relationship was obtained between turbidity and the concentration of clay particles determined by imaging. The analysis technique was applied to characterize flocs and floc particle size distribution as a function of coagulant dose. Removal of flocs by sedimentation was characterized by imaging, and the negative logarithm of the fraction of turbidity remaining after settling had a linear relationship with the logarithm of aluminum dose. The maximum floc size observed in the settled water was less than 120 µm, which was in accordance with the value predicted by a model for the capture velocity of the experimental tube settler of 0.21 mm/s.

10.
Zhonghua Yu Fang Yi Xue Za Zhi ; 48(7): 555-60, 2014 Jul.
Artigo em Zh | MEDLINE | ID: mdl-25312560

RESUMO

OBJECTIVE: To study the epidemiological status of diabetes' risk factors among urban and suburban residents and their perceptions of their own health status and risk of diabetes. METHODS: Stratified multi-stage sampling method was used to conduct the survey among 18-60 years old residents from Zhejiang, Jiangsu, Shanxi, Henan, Yunnan, and Qinghai provinces in China from March to May in 2013. The Questionnaire of Health Literacy of Diabetes Mellitus of the Public in China was used to conduct the survey, and then the data were analyzed. The main contents of the questionnaire included diabetes mellitus knowledge, diabetes mellitus risk factors and diabetes mellitus risk self-assessment. The results of the survey were standardized by the 6(th) national census data. RESULTS: A total of 4 416 respondents were surveyed, and 4 282 valid questionnaires were successfully collected during the survey and the response rate was 97.0%. After weighted adjustment, the overweight and obesity rate of the residents in 6 provinces was 35.3%, abdominal obesity rate was 54.7%. 77.8% of the residents without diabetes had more than one risk factor, but only 8.5% thought they might got diabetes. The residents with high risk behavior possessing rates of diabetes were in eastern areas (79.7%), urban areas (80.7%), men (84.1%), aged from 45 to 60(100.0%), below primary school education level (83.4%) and enterprise personnel (79.7%). The residents with high risk consciousness of getting diabetes were in eastern areas (11.0%), urban areas (9.7%), men (9.7%), aged from 45 to 60 (12.3%), over college education level (12.7%) and the offices (14.7%). The results of logistic regression showed that residents in the middle areas (OR = 2.148, 95% CI: 1.633-2.920), urban residents (OR = 2.100, 95% CI: 1.611-2.738), male (OR = 2.488, 95% CI: 1.962-3.154), the older (OR = 1.102, 95% CI: 1.090-1.115) had a higher risk behavior rate of diabetes mellitus. Urban residents (OR = 2.784, 95% CI: 1.497-5.175), male (OR = 1.522, 95% CI: 1.152-2.011), the older (OR = 1.022, 95% CI: 1.009-1.035), college educational level (OR = 1.685, 95% CI: 1.033-2.749), with a higher score of health awareness(OR = 1.090, 95% CI: 1.061-1.120)had a higher risk consciousness to being diabetes mellitus. CONCLUSION: The urban and suburban residents in China had a high risk behavior possessing rates of diabetes, and a low risk consciousness of being diabetes.


Assuntos
Diabetes Mellitus , Conhecimentos, Atitudes e Prática em Saúde , Fatores de Risco , Adulto , China/epidemiologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Obesidade , População Suburbana , Inquéritos e Questionários , População Urbana
11.
Zhonghua Yu Fang Yi Xue Za Zhi ; 48(7): 571-5, 2014 Jul.
Artigo em Zh | MEDLINE | ID: mdl-25312563

RESUMO

OBJECTIVE: To explore the status of diabetes-related behaviors and affecting factors among urban and suburban residents in China. METHODS: A sample of 18-60 years old residents from Zhejiang, Jiangsu, Shanxi, Henan, Yunnan and Qinghai provinces was investigated by using stratified cluster random sampling method from March to May in 2013, and 4 282 residents were recruited. The Questionnaire of Health Literacy of Diabetes Mellitus of the Public in China was used to conduct the survey. χ(2) test was used to compare the different risk behavior characteristics of diabetes. The results of the survey were standardized by the 6th national census data. Multiple regression analysis was used to understand the affecting factors to related behaviors. RESULTS: After data standardization, 14.3% sat more than 6 hours every day, 57.6% exercised less than 3 times every week, 21.3% had no regularly daily diet, 58.7% paid no attention to diet control, 15.7% and 7.8% residents preferred salty and oily diet, 51.4% had physical examination less than 1 time every year, 29.7% were smokers, and 9.2% often drank. Urban residents spent much more time on sitting (18.2%) than rural residents (8.4%) (P < 0.05), and the rates of lack of physical exercise(52.7%), irregular diet (17.2%), paying no attention to diet control (51.9%), smokers (23.6%) among urban residents were lower than rural residents (60.1%, 21.4%, 62.5% and 32.1% respectively) (P < 0.05). The rates of irregular diet (24.6%), paying no attention to diet control (63.5%), high-salt and high-fat diet (30.1%), smokers (57.7%), drinking (18.7%) among men were higher than those in females (15.5%, 52.1%, 23.2%, 2.2%, and 0.8% respectively) (P < 0.05); regions, genders, educational levels, occupations were related to relative behaviors of diabetes, residents in rural areas (t = 7.829, P < 0.01), males (t = -21.760, P < 0.01), lower education level (t = 0.771, P < 0.01), as well as institution personnel (t = -4.240, P < 0.01) had lower behavior scores, which meant they had more risk behaviors related to diabetes. CONCLUSION: There were diabetes-related risk behaviors among both urban and suburban residents in China, such as insufficient physical exercise, no diet control and regular medical examinations. These risk behaviors happened more in rural areas than in urban areas, men than women, older age group than lower age group.


Assuntos
Demografia , Diabetes Mellitus , Comportamentos Relacionados com a Saúde , Adulto , Fatores Etários , Consumo de Bebidas Alcoólicas , China/epidemiologia , Dieta , Dieta Hiperlipídica , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ocupações , Fatores de Risco , População Rural , Fatores Sexuais , Inquéritos e Questionários , População Urbana , Adulto Jovem
12.
Zhonghua Yu Fang Yi Xue Za Zhi ; 48(7): 576-80, 2014 Jul.
Artigo em Zh | MEDLINE | ID: mdl-25312564

RESUMO

OBJECTIVE: To explore the status of diabetes prevention awareness among Chinese residents in order to provide the scientific basis for making intervention strategy. METHODS: A sample of 18-60 years old residents in six provinces was investigated from March to April in 2013. RESULTS: Totally, 17.8% of respondents answered all questions correctly about the awareness of diabetes. As for "Diabetes is a common chronic disease" got highest recognition rate (86.2%), and "Diabetes can be cured" got the lowest rate, 48.3%. 50.6% of respondents answered all questions correctly about the diabetes symptoms; and "thirsty, drink more water" got the highest recognition rate (75.3%). 17.8% of respondents answered all questions correctly about the complications of diabetes; and "causes of diabetes ketoacidosis" got the lowest rate of 31.6%. 12.3% of respondents answered all questions correctly about the diabetes high-risk group; the correct recognition rate for "family history" was the highest (75.1%); and the "macrosomia" got the lowest rate of 20.4%. 74.2% of respondents answered all questions correctly about the diabetes preventive measure;the correct cognition rate of a reasonable diet was the highest (92.0%), and the weight control was the lowest (81.5%). In addition, there are significant differences of knowledge score between different areas and genders. City residents' knowledge score about diabetes related views (6.2 ± 1.8), typical symptoms (2.9 ± 1.4), complication (4.1 ± 2.3), high-risk groups (3.4 ± 1.7), prevention measures (3.7 ± 0.9) were higher than rural residents (respectively 5.2 ± 2.2, 2.7 ± 1.5, 3.2 ± 2.3, 2.9 ± 1.8, 3.3 ± 1.2) (P < 0.05). Female residents' knowledge score about diabetes related views (5.7 ± 2), typical symptoms (2.9 ± 1.4), complication (3.8 ± 2.3), high-risk groups (3.1 ± 1.8), prevention measures (3.5 ± 1) were higher than male residents (respectively 5.5 ± 2.1, 2.7 ± 1.5, 3.5 ± 2.4, 3.1 ± 1.8, 3.4 ± 1.2, 18.1 ± 6.8) (P < 0.05). CONCLUSION: The public is lack of diabetes prevention awareness, and city residents' knowledge score is higher than rural residents', females are higher than males.


Assuntos
Diabetes Mellitus , Conhecimentos, Atitudes e Prática em Saúde , Adulto , Povo Asiático , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , População Rural , Fatores Sexuais , População Urbana , Adulto Jovem
13.
Int J Biol Macromol ; 273(Pt 2): 133224, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38897518

RESUMO

In recent years, with the booming of the edible mushroom industry, chitin production has become increasingly dependent on fungi and other non-traditional sources. Fungal chitin has advantages including superior performance, simpler separation processes, abundant raw materials, and the absence of shellfish allergens. As a kind of edible mushroom, flammulina velutipes (F. velutipes) also has the advantages of wide source and large annual yield. This provided the possibility for the extraction of chitin. Here, a procedure to extract chitin from F. velutipes waste be presented. This method comprises low-concentration acid pretreatment coupled with consolidated bioprocessing with Aspergillus niger. Characterization by SEM, FTIR, XRD, NMR, and TGA confirmed that the extracted chitin was ß-chitin. To achieve optimal fermentation of F. velutipes waste (80 g/L), ammonium sulfate and glucose were selected as nitrogen and carbon sources (5 g/L), with a fermentation time of 5 days. The extracted chitin could be further deacetylated and purified to obtain high-purity chitosan (99.2 % ± 1.07 %). This chitosan exhibited a wide degree of deacetylation (50.0 % ± 1.33 % - 92.1 % ± 0.97 %) and a molecular weight distribution of 92-192 kDa. Notably, the yield of chitosan extracted in this study was increased by 56.3 % ± 0.47 % compared to the traditional chemical extraction method.

14.
Environ Sci Pollut Res Int ; 31(8): 11647-11665, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38224433

RESUMO

The oxidation characteristics and spontaneous combustion (SC) tendency of raw long-flame coal (RC), water-soaked 200-day coal (S200), pre-oxidized water-soaked coal at 200 °C (O200S200), and pre-oxidized soaked coal at 300 °C (O300S200) in an oxygen-poor environment were investigated using a programmed warming system. The results show that pre-oxidation water-soaked treatment (PWT) promotes the coal-oxygen complex reaction and increases the rate of coal oxygen consumption (OCR) and the rate of carbon and oxygen compound production. The rate of CO and CO2 production of the water-soaked (WS) coal increased by 0.329 mol·(cm3·s)-1 and 0.922 mol·(cm3·s)-1, respectively, compared with that of the original coal sample. PWT reduces the activation energy of coal in the low-temperature oxidation stage (the maximum difference can be up to 110.99 kJ/mol) and enhances the oxidizing and heat-releasing capacity. There was a synergistic effect between the pre-oxidation (PO) and WS treatment, and the lowest comprehensive determination index of the SC propensity of coal in O200S200 samples was 831.92 which was 4.72 lower than that of RC samples, presenting a more SC tendency. Low oxygen concentration has an inhibitory effect on the oxidation characteristic parameters of coal, and the apparent activation energy of the low-temperature oxidation stage of pre-oxidized water-soaked coal (PWC) increased to 206.418 kJ/mol at 3% oxygen concentration. The lower the oxygen concentration of the anoxic environment, the lower the risk of SC of the coal samples. The results of the study can provide theoretical guidance for the identification and prevention of SC disasters in coal seams with shallow burial and close spacing.


Assuntos
Carvão Mineral , Oxigênio , Oxigênio/análise , Combustão Espontânea , Água , Temperatura Alta
15.
J Colloid Interface Sci ; 633: 546-554, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36470135

RESUMO

Defects engineering has played an ever-increasing important role in electrochemistry, especially secondary lithium batteries. TiO2 is regarded as a promising anode due to its attractive cycling stability, low volume strain and great abundance, while challenges of intrinsic poor electrical and ionic conductivity remain to be addressed. Herein, we report a three-in-one oxygen vacancy (VO)-involved pomegranate design for TiO2-x/C composite anode, which provides highly improved electrical conduction, shortened Li+ pathway and promoted Li+ redox. N-doped mesoporous carbon acts as a robust scaffold to support the whole structure, electron highway and efficient reductant to generate VO on TiO2 nanoparticles during crystallization. Theoretical calculations reveal the crucial role of surface VO on TiO2 in Li electrochemistry. Resultantly, the optimal TiO2-x/C anode achieves significantly enhanced cycling performance (203 mAh/g retained after 2000 cycles at 1 A/g). Postmortem analysis reveals the robustness of VO and reasonable structure stability upon cycles for improved battery performance.


Assuntos
Carbono , Lítio , Cristalização , Oxigênio
16.
Sci Total Environ ; 890: 164354, 2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37230362

RESUMO

With the normalization of deep mining, the risk of residual coal spontaneous combustion (CSC) in deeply mined areas has gradually increased. To investigate the thermal characteristics and microgroup transformation mechanisms during the secondary oxidation of deep-well oxidized coal, a deep-well oxidation process was simulated in a synchronous thermal analyzer, and the thermal parameters of the oxidized coal were tested. The correlated transformation pathways of microscopic active groups was studied by electron paramagnetic resonance (EPR) and in situ diffuse reflectance (in situ FTIR) experiments during the reoxidation of oxidized coal. The results showed that with increasing deep-well ambient temperature and oxidation temperature, the characteristic temperature of coal gradually decreased, exothermic heat release gradually increased, and active aliphatic structures and -OH, -CHO and other active functional groups gradually accumulated and became distributed more uniformly. When the thermal conditions and oxidation temperature were very high (> 160 °C), the active free radicals in the oxidized coal were rapidly consumed, resulting in a gradual decrease in the characteristic temperature and heat release during the secondary oxidation process, while the contents of peroxy and carboxyl groups continued to increase. In the slow oxidation stage of oxidized coal, methyl groups were mainly transformed with hydroxyl and peroxide groups (r > 0.96), and the associated oxidative consumption of -CHO and -COOH mainly occurred in the rapid oxidation stage (r > 0.99). Geminal diols and peroxy groups are important intermediates in the coal-oxygen composite reaction process. With an increase in the deep-well temperature and initial oxidation temperature, the reoxidation tendency and heat release capacity of residual coal in the goaf gradually increased, and the risk of CSC intensified. The research results provide a theoretical reference for the prevention and control of coal fires in deep mines and play an important role in guiding environmental management and gas emissions reduction measures in mining areas.


Assuntos
Carvão Mineral , Incêndios , Combustão Espontânea , Temperatura , Temperatura Alta
17.
J Colloid Interface Sci ; 641: 386-395, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36940595

RESUMO

Spinel bimetallic transition metal oxide anode such as ZnMn2O4, has drawn increasing interest due to attractive bimetal interaction and high theoretical capacity. While it suffers from huge volume expansion and poor ionic/electronic conductivity. Nanosizing and carbon modification can alleviate these issues, while the optimal particle size within host is unclear yet. We here propose an in-situ confinement growth strategy to fabricate pomegranate-structured ZnMn2O4 nanocomposite with calculated optimal particle size in mesoporous carbon host. Theoretical calculations reveal favorable interatomic interactions between the metal atoms. By the synergistic effects of structural merits and bimetal interaction, the optimal ZnMn2O4 composite achieves greatly improved cycling stability (811 mAh g-1 at 0.2 A g-1 after 100 cycles), which can maintain its structural integrity upon cycling. X-ray absorption spectroscopy analysis further confirms delithiated Mn species (Mn2O3 but little MnO). Briefly, this strategy brings new opportunity to ZnMn2O4 anode, which could be adopted to other conversion/alloying-type electrodes.

18.
Front Psychol ; 13: 879284, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35645907

RESUMO

Fostering subordinate moqi is a significant method to improve the cooperating quality and promote positive outcomes. However, little is known about the influencing factors and mechanisms of subordinate moqi. To address this issue and explore the influencing factors of subordinate moqi, we draw on self-categorization theory to develop a mediation model to examine whether and how deep-level similarity affects subordinate moqi, casting the leader-member exchange (LMX) as a mediator. A two-wave online survey was conducted and 316 data was collected. A Structure Equation Modeling analysis was used to test all hypotheses with Mplus 7. Results showed that the deep-level similarity could positively predict subordinate moqi and LMX, respectively. Additionally, LMX was a significant predictor of subordinate moqi as well as it mediated the positive relationships between deep-level similarity and subordinate moqi. These findings expand our understanding of the antecedents of subordinate moqi. It is suggested that developing subordinates' deep-level similarity with supervisors and LMX relationships are instrumental in cultivating subordinate moqi which promote positive outcomes. Organizations should integrate effective management programs into managerial strategies to enhance deep-level similarity and LMX, in turn, fosters subordinate moqi.

19.
Int J Biol Macromol ; 214: 601-609, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35760162

RESUMO

This paper describes a new method combining octenyl succinic anhydride (OSA) esterification and high hydrostatic pressure for starch modification, which interacts with conjugated linoleic acid (CLA) to form an octenyl succinic anhydride-lotus seed starch-conjugated linoleic acid (OSA-LS-CLA) complex. This method proves the formation of complex observed by fourier transform infrared spectroscopy and complex index. The stable structure of the complex was derived from increasing molecular weight by introducing macromolecular conjugated linoleic acid and the higher crystallinity than original starch observed by X-ray diffraction. The formation method and changes of complex were observed by scanning electron microscopy and confocal laser scanning microscope. The solubility and swelling power of the complex increases as the temperature increased, significantly at 75 °C. The formation of the OSA-LS-CLA complex significantly reduced the digestion rate of LS, which was 26 % lower than that of LS. These results indicate that the OSA-LS-CLA under high hydrostatic pressure can form a complex with stable structure, which makes up for the deficiency of raw starch to a certain extent. And the formation of this structure can improve the thermal stability of the complex and has strong digestion resistance, which provides a potential direction for further research in reducing starch digestibility.


Assuntos
Ácidos Linoleicos Conjugados , Anidridos Succínicos , Esterificação , Sementes/química , Amido/química , Anidridos Succínicos/química
20.
Artigo em Inglês | MEDLINE | ID: mdl-36361105

RESUMO

Attention to physical and mental health is becoming more intensive. In China, factors and mechanisms are now a focus of research. We used dynamic air quality monitoring data and the Chinese General Social Survey (CGSS) to assess the spatial differences and the coupling between subjective and objective air pollution. In addition, a logistic model was used to explore the impact mechanisms of social inequality, air pollution, food safety, and lack of green space on health. The results show that (1) the impact of subjective and objective air pollution on the health level of the population is significant; (2) income inequality, air pollution, food pollution, and travel behavior significantly affect the residents' health; and (3) environmental health has a significant differentiation mechanism between urban and rural areas. The negative health effects of air pollution and insufficient green space are more significant in cities; food pollution is more likely in rural areas. In terms of socioeconomic inequality, gender, family size, travel, and physical exercise had no significant effect on rural health. Health improvement was higher in the low-income group than in the high-income group. The adverse effect of travel behavior on environmental pollution is conducive to improving health. Therefore, social equality, strictly controlled environmental pollution, exercise, and travel can help narrow the gap between rich and poor, promote urban-rural health equity, and improve human health.


Assuntos
Poluição do Ar , Parques Recreativos , Humanos , Análise de Dados , Poluição do Ar/análise , China/epidemiologia , Fatores Socioeconômicos
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