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1.
Front Plant Sci ; 15: 1392924, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39006959

RESUMO

Roads are an increasingly prevalent form of human activity that drives the decrease in plant community functions and threatens global biodiversity. However, few studies have focused on the changes in the function and diversity of alpine meadows caused by road infrastructure in the Tibetan Plateau. In this study, the changes in species diversity, functional diversity, and community stability were examined at different distances from the Qinghai-Tibet highway. The results showed that the road intensified the degradation of vegetation, which significantly altered species diversity and community structure. This effect gradually decreased from near to far from the highway. Plant community cover and species diversity were highest at intermediate distances (50-100 m) from the roadway; species diversity and stability were lowest in the grassland most disturbed by the road (0 m), and species diversity and functional diversity tended to stabilize farther away from the road (250 m). Our findings indicate that changes in species diversity are synchronized with changes in functional diversity, which largely determines the outcome of degraded grassland community diversity and stability. Our results provide a reference point for restoring degraded alpine areas and mitigating the ecological impacts of roads.

2.
J Affect Disord ; 362: 230-236, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38969024

RESUMO

BACKGROUND: To explore the risk factors of post-traumatic stress disorder (PTSD) among Chinese college students during the COVID-19 pandemic and the construction and validation of risk prediction models. METHODS: A total of 10,705 university students were selected for the study. The questionnaire included the Generalized Anxiety Disorder 7 (GAD-7), Patient Health Questionnaire 9 (PHQ-9), PTSD Checklist for DSM-5 (PCL-5), and self-designed questionnaire. These assessments were conducted to facilitate the survey, construct the predictive model and validate the model's validity. RESULTS: Sex, left-behind experience, poverty status, anxiety score, and depression score were identified as independent risk factors influencing psychological trauma among Chinese college students during the COVID-19 pandemic, while COVID-19 infection emerged as a protective factor against psychological trauma. A column chart was constructed to visualize the six independent risk factors derived from logistic regression analysis. The Hosmer-Lemeshow test results (χ2 = 13.021, P = 0.111) indicated that the risk prediction model fitted well. The receiver operating characteristic (ROC) curve showed an area under the curve (AUC) of 0.864 in the model group and 0.855 in the validation group. The calibration curves of the model closely resembled the ideal curve. Decision curve analysis (DCA) revealed that the model provided net benefit and demonstrated good clinical utility. LIMITATIONS: The validation of the model is currently restricted to internal assessments. However, further confirmation through larger sample sizes, multicenter investigations, and prospective studies is necessary. CONCLUSIONS: The model effectively predicted PTSD risk among Chinese college students during the COVID-19 pandemic, indicating strong clinical applicability.

3.
Nano Lett ; 24(19): 5714-5721, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38695488

RESUMO

The structure of solvated Li+ has a significant influence on the electrolyte/electrode interphase (EEI) components and desolvation energy barrier, which are two key factors in determining the Li+ diffusion kinetics in lithium metal batteries. Herein, the "solvent activity" concept is proposed to quantitatively describe the correlation between the electrolyte elements and the structure of solvated Li+. Through fitting the correlation of the electrode potential and solvent concentration, we suggest a "low-activity-solvent" electrolyte (LASE) system for deriving a stable inorganic-rich EEI. Nano LiF particles, as a model, were used to capture free solvent molecules for the formation of a LASE system. This advanced LASE not only exhibits outstanding antidendrite growth behavior but also delivers an impressive performance in Li/LiNi0.8Co0.1Mn0.1O2 cells (a capacity of 169 mAh g-1 after 250 cycles at 0.5 C).

4.
Natl Sci Rev ; 11(4): nwae042, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38487497

RESUMO

Tracking the dynamic surface evolution of metal halide perovskite is crucial for understanding the corresponding fundamental principles of photoelectric properties and intrinsic instability. However, due to the volatility elements and soft lattice nature of perovskites, several important dynamic behaviors remain unclear. Here, an ultra-high vacuum (UHV) interconnection system integrated by surface-sensitive probing techniques has been developed to investigate the freshly cleaved surface of CH3NH3PbBr3  in situ under given energy stimulation. On this basis, the detailed three-step chemical decomposition pathway of perovskites has been clarified. Meanwhile, the evolution of crystal structure from cubic phase to tetragonal phase on the perovskite surface has been revealed under energy stimulation. Accompanied by chemical composition and crystal structure evolution, electronic structure changes including energy level position, hole effective mass, and Rashba splitting have also been accurately determined. These findings provide a clear perspective on the physical origin of optoelectronic properties and the decomposition mechanism of perovskites.

5.
Adv Mater ; 36(15): e2310260, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38116707

RESUMO

The evaporation-induced hydrovoltaic effect based on ion-selective nanochannels can theoretically be employed for high-performance ion sensing; yet, the indeterminate ion-sensing properties and the acquisition of high sensing performance are rarely explored. Herein, a controllable nanochannel regulation strategy for flexible hydrovoltaic devices with highly sensitive ion-sensing abilities is presented across a wide concentration range. By multiple dip-coating of silk fibroin (SF) on an electrospinning nylon-66 nanofiber (NNF) film, the surface polarity enhancement, the fibers size regulation with a precision of ≈25 nm, and the nanostructure firm binding are achieved simultaneously. The resultant flexible freestanding hydrovoltaic device exhibits an open circuit voltage up to 4.82 V in deionized water, a wide ion sensing range of 10-7 to 100 m, and ultrahigh sensitivity as high as 1.37 V dec-1, which is significantly higher than the sensitivity of the traditional solid-contact ion-selective electrodes (SC-ISEs). The fabricated flexible ion-sensitive hydrovoltaic device is successfully applied for wearable human sweat electrolyte sensing and for environmental trace-ion monitoring, thereby confirming the potential application of the hydrovoltaic effect for ion sensing.

6.
Front Microbiol ; 14: 1242506, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37779708

RESUMO

Despite the widespread application of decentralized wastewater treatment (WWT) facilities in China, relatively few research has used the multi-media biological filter (MMBF) facilities to investigate the microorganism characteristics. This study utilizes 16S rRNA high-throughput sequencing (HTS) technology to examine the microbial biodiversity of a representative wastewater treatment (WWT) system in an expressway service area. The pathways of nitrogen removal along the treatment route were analyzed in conjunction with water quality monitoring. The distribution and composition of microbial flora in the samples were examined, and the dominant flora were identified using LEfSe analysis. The FAPROTAX methodology was employed to investigate the relative abundance of genes associated with the nitrogen cycle and to discern the presence of functional genes involved in nitrogen metabolism. On average, the method has a high level of efficiency in removing COD, TN, NH3-N, and TP from the effluent. The analysis of the microbial community identified a total of 40 phyla, 111 classes, 143 orders, 263 families, and 419 genera. The phyla that were predominantly observed include Proteobacteria, Acidobacteria, Chloroflexi, Actinobacteria, Nitrospirae, Bacteroidetes. The results show that the system has achieved high performance in nitrogen removal, the abundance of nitrification genes is significantly higher than that of other nitrogen cycle genes such as denitrification, and there are six nitrogen metabolism pathways, primarily nitrification, among which Nitrospirae and Nitrospira are the core differentiated flora that can adapt to low temperature conditions and participate in nitrification, and are the dominant nitrogen removal flora in cold regions. This work aims to comprehensively investigate the diversity and functional properties of the bacterial community in decentralized WWT processes.

7.
Rev Med Chil ; 150(1): 115-119, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35856973

RESUMO

Insulin antibodies (IAs) induced by exogenous insulin rarely cause hypoglycemia. However, insulin autoantibodies (IAAs) in insulin autoimmune syndrome (IAS) can cause hypoglycemia. The typical manifestations of IAS are fasting or postprandial hypoglycemia, elevated insulin level, decreased C-peptide levels, and positive IAA. We report a 45-year-old male with type 1 diabetes mellitus (T1DM) treated with insulin analogues suffering from recurrent hypoglycemic coma and diabetic ketoacidosis (DKA). His symptoms were caused by exogenous insulin and were similar to IAS. A possible reason was that exogenous insulin induced IA. IA titers were 61.95% (normal: < 5%), and the concentrations of insulin and C-peptide were > 300 mU/L and < 0.02 nmol/L when hypoglycemia occurred. Based on his clinical symptoms and other examinations, he was diagnosed with hyperinsulinemic hypoglycemia caused by IA. His symptoms improved after changing insulin regimens from insulin lispro plus insulin detemir to recombinant human insulin (Gensulin R) and starting prednisone.


Assuntos
Doenças Autoimunes , Diabetes Mellitus Tipo 1 , Cetoacidose Diabética , Hipoglicemia , Doenças Autoimunes/diagnóstico , Peptídeo C/uso terapêutico , Coma , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/tratamento farmacológico , Cetoacidose Diabética/induzido quimicamente , Cetoacidose Diabética/complicações , Cetoacidose Diabética/tratamento farmacológico , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Insulina/uso terapêutico , Anticorpos Anti-Insulina/uso terapêutico , Masculino , Pessoa de Meia-Idade
8.
Zhongguo Gu Shang ; 35(1): 33-7, 2022 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-35130596

RESUMO

OBJECTIVE: To explore the effect of Chinese massage on the rehabilitation of scoliosis patients undergoing 3D printing orthopedics. METHODS: A retrospective selection of 262 patients with adolescent idiopathic scoliosis(AIS) who underwent 3D printing technology orthopedics admitted to the Department of Orthopedics in our hospital from January 2013 to January 2019 were selected for clinical research. According to the rehabilitation treatment methods adopted by the patients after the operation, the patients were divided into control group and observation group, there were 131 cases in each group. The observation group was treated with traditional Chinese acupuncture and massage after operation, and the control group was treated with conventional rehabilitation. The torso rotation angle and the maximum Cobb angle before and after intervention were measured and compared between two groups, Oswestry Disability Index(ODI) was used for functional evaluation, and the visual analogue scale(VAS) was used to evaluate the changes in pain before and after rehabilitation intervention. RESULTS: After the intervention, the trunk rotation angle and maximum Cobb angle of the observation group were significantly better than those of the control group, the VAS score of the observation group was significantly lower than that of the control group, ODI in the observation group was significantly lower than that in the control group, and the difference was statistically significant(P<0.05). CONCLUSION: After scoliosis patients undergo preoperative 3D printing correction, the scientific and reasonable implementation of TCM acupuncture and massage can effectively improve the patient's vertebral rotation angle, maximum Cobb angle, and improve the patient's spinal function.


Assuntos
Procedimentos Ortopédicos , Ortopedia , Escoliose , Fusão Vertebral , Adolescente , Humanos , Vértebras Lombares/cirurgia , Massagem , Medicina Tradicional Chinesa , Impressão Tridimensional , Estudos Retrospectivos , Escoliose/cirurgia , Resultado do Tratamento
9.
Rev. méd. Chile ; 150(1): 115-119, ene. 2022. tab
Artigo em Inglês | LILACS | ID: biblio-1389609

RESUMO

ABSTRACT Insulin antibodies (IAs) induced by exogenous insulin rarely cause hypoglycemia. However, insulin autoantibodies (IAAs) in insulin autoimmune syndrome (IAS) can cause hypoglycemia. The typical manifestations of IAS are fasting or postprandial hypoglycemia, elevated insulin level, decreased C-peptide levels, and positive IAA. We report a 45-year-old male with type 1 diabetes mellitus (T1DM) treated with insulin analogues suffering from recurrent hypoglycemic coma and diabetic ketoacidosis (DKA). His symptoms were caused by exogenous insulin and were similar to IAS. A possible reason was that exogenous insulin induced IA. IA titers were 61.95% (normal: 300 mU/L and < 0.02 nmol/L when hypoglycemia occurred. Based on his clinical symptoms and other examinations, he was diagnosed with hyperinsulinemic hypoglycemia caused by IA. His symptoms improved after changing insulin regimens from insulin lispro plus insulin detemir to recombinant human insulin (Gensulin R) and starting prednisone.


Los anticuerpos contra la insulina (AI) inducidos por la insulina exógena raramente causan hipoglucemia. No obstante, los autoanticuerpos contra la insulina (AIA) en el síndrome autoinmune de insulina (SAI) pueden causar hipoglucemia. Las manifestaciones típicas del SAI son la hipoglucemia en ayunas o posprandial, niveles elevados de insulina, la disminución del nivel de péptido C y AIA positivos. Presentamos un paciente hombre de 45 años con diabetes mellitus de tipo 1 (DMT1) tratado con análogos de insulina, que sufría comas hipoglucémicos recurrentes y cetoacidosis diabética (CAD). Sus síntomas fueron causados por la insulina exógena y fueron similares al SAI. La posible razón fue que la insulina exógena indujo AI. El título de AI era del 61,95% (Normal: 300 mU/L y < 0,02 nmol/L cuando se producía la hipoglucemia. Basados en sus síntomas clínicos y otros exámenes, se le diagnosticó hipoglucemia hiperinsulinémica causada por la AI. Sus síntomas mejoraron después de cambiar el régimen de insulina de lispro más insulina detemir a insulina humana recombinante (Gensulin R) y de empezar a tomar prednisona.


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Doenças Autoimunes/diagnóstico , Cetoacidose Diabética/complicações , Cetoacidose Diabética/induzido quimicamente , Cetoacidose Diabética/tratamento farmacológico , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemia/induzido quimicamente , Peptídeo C/uso terapêutico , Coma , Hipoglicemiantes/efeitos adversos , Insulina/uso terapêutico , Anticorpos Anti-Insulina/uso terapêutico
10.
Nanomaterials (Basel) ; 11(11)2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34835855

RESUMO

This letter reports room-temperature electrically pumped narrow-linewidth GaN-on-Si laser diodes. Unlike conventional distributed Bragg feedback laser diodes with hundreds of gratings, we employed only a few precisely defined slot gratings to narrow the linewidth and mitigate the negative effects of grating fabrication on the device performance. The slot gratings were incorporated into the ridge of conventional Fabry-Pérot cavity laser diodes. A subsequent wet etching in a tetramethyl ammonium hydroxide solution not only effectively removed the damages induced by the dry etching, but also converted the rough and tilted slot sidewalls into smooth and vertical ones. As a result, the threshold current was reduced by over 20%, and the reverse leakage current was decreased by over three orders of magnitude. Therefore, the room-temperature electrically pumped narrow-linewidth GaN-on-Si laser diode has been successfully demonstrated.

11.
Water Res ; 62: 88-96, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24937358

RESUMO

Cement-based and alternative cementitious materials were tested in the laboratory for their capability of removing phosphate from wastewater. The results demonstrated that both Langmuir and Freundlich adsorption isotherms were suitable for describing the adsorption characteristics of these materials. Among the four types of filter media tested, the cement-based mortar A has the highest value of maximum adsorption (30.96 mg g(-1)). The P-bonding energy (KL) and adsorption capacity (K) exhibited a positive correlation with the total content of Al2O3 and Fe2O3 in each mortar. The maximum amount of P adsorbed (Qm) and adsorption intensity (1/n) exhibited a positive correlation with the CaO content in each mortar. For three of them, the P-removal rates were in excess of 94 percent for phosphorus concentrations ranging from 20 to 1000 mg L(-1). The underlying mechanisms were examined using field emission scanning microscopy (FESEM), coupled with energy-dispersive X-ray spectroscopy (EDX) and X-ray powder diffraction (XRD). The results reveal that the removal of phosphate predominantly followed a precipitation mechanism in addition to weak physical interactions between the surface of adsorbent filter media and the metallic salts of phosphate. The use of cement-based or alternative cementitious materials in the form of ground powder shows great promise for developing a cost-effective and environmentally sustainable technology for P-sequestration and for wastewater treatment.


Assuntos
Materiais de Construção , Fósforo/isolamento & purificação , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Cinética , Soluções , Espectrometria por Raios X , Temperatura
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