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1.
J Youth Adolesc ; 53(7): 1615-1629, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38300442

RESUMO

Existing research on non-suicidal self-injury (NSSI) among adolescents has primarily concentrated on general risk factors, leaving a significant gap in understanding the specific NSSI characteristics that predict diverse psychopathological outcomes. This study aims to address this gap by using Random Forests to discern the significant predictors of different clinical outcomes. The study tracked 348 adolescents (64.7% girls; mean age = 13.31, SD = 0.91) over 6 months. Initially, 46 characteristics of NSSI were evaluated for their potential to predict the repetition of NSSI, as well as depression, anxiety, and suicidal risks at a follow-up (T2). The findings revealed distinct predictors for each psychopathology. Specifically, psychological pain was identified as a significant predictor for depression, anxiety, and suicidal risks, while the perceived effectiveness of NSSI was crucial in forecasting its repetition. These findings imply that it is feasible to identify high-risk individuals by assessing key NSSI characteristics, and also highlight the importance of considering diverse NSSI characteristics when working with self-injurers.


Assuntos
Depressão , Comportamento Autodestrutivo , Humanos , Comportamento Autodestrutivo/psicologia , Feminino , Masculino , Adolescente , Depressão/psicologia , Fatores de Risco , Ansiedade/psicologia , Comportamento do Adolescente/psicologia , Ideação Suicida , Algoritmo Florestas Aleatórias
2.
Artigo em Inglês | MEDLINE | ID: mdl-38110758

RESUMO

Parental psychological control (PPC) is associated with adolescent non-suicidal self-injury (NSSI); however, its underlying mechanisms have not been extensively investigated. Considering that genetic and environmental factors interactively influence adolescent development, this study examined whether the parent-adolescent relationship mediated the link between PPC and adolescent NSSI, and whether this mediating process was moderated by the oxytocin receptor gene rs53576 polymorphism (OXTR rs53576). Participants comprised 673 adolescents (Meanage = 12.81 years, SD = 0.48 years) who completed questionnaires regarding PPC, the parent-adolescent relationship, and NSSI. DNA was extracted from each participant's saliva samples. The results indicated that the positive association between PPC and adolescent NSSI was mediated by the parent-adolescent relationship. Moreover, this indirect link was stronger for adolescents with AA homozygotes of OXTR rs53576 than for those with the GG or AG genotype. These findings extend our understanding of the association between PPC and adolescent NSSI and suggest that a simultaneous focus on PPC, the parent-adolescent relationship, and OXTR rs53576 may favor NSSI interventions.

3.
BMC Infect Dis ; 21(1): 841, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34416851

RESUMO

AIM: This study has conducted a comparative analysis of common carbapenemases harboring, the expression of resistance-nodulation-cell division (RND) family efflux pumps, and biofilm formation potential associated with carbapenem resistance among Acinetobacter baumannii (A. baumannii) strains with different carbapenem susceptibility. METHODS: A total of 90 isolates of A. baumannii from two tertiary hospitals of China were identified and grouped as carbapenem susceptible A. baumannii (CSAB) strains and carbapenem non-susceptible A. baumannii (CnSAB) strains based on the susceptibility to imipenem. Harboring of carbapenemase genes, relative expression of RND family efflux pumps and biofilm formation potential were compared between the two groups. RESULT: Among these strains, 12 (13.3 %) strains were divided into the CSAB group, and 78 (86.7 %) strains into the CnSAB group. Compared with CSAB strains, CnSAB strains increased distribution of blaOXA-23 (p < 0.001) and ISAba1/blaOXA-51-like (p = 0.034) carbapenemase genes, and a 6.1-fold relative expression of adeB (p = 0.002), while CSAB strains led to biofilm formation by 1.3-fold than CnSAB strains (p = 0.021). CONCLUSIONS: Clinically, harboring more blaOXA-23-like and ISAba1/blaOXA-51-like complex genes and overproduction of adeABC are relevant with carbapenem resistance, while carbapenem susceptible strains might survive the stress of antibiotic through their ability of higher biofilm formation.


Assuntos
Acinetobacter baumannii , Acinetobacter baumannii/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Biofilmes , Carbapenêmicos/farmacologia , Divisão Celular , Testes de Sensibilidade Microbiana , beta-Lactamases/genética
4.
Faraday Discuss ; 197: 59-86, 2017 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-28332665

RESUMO

Condensation and esterification are important catalytic routes in the conversion of polyols and oxygenates derived from biomass to fuels and chemical intermediates. Previous experimental studies show that alkanal, alkanol and hydrogen mixtures equilibrate over Cu/SiO2 and form surface alkoxides and alkanals that subsequently promote condensation and esterification reactions. First-principle density functional theory (DFT) calculations were carried out herein to elucidate the elementary paths and the corresponding energetics for the interconversion of propanal + H2 to propanol and the subsequent C-C and C-O bond formation paths involved in aldol condensation and esterification of these mixtures over model Cu surfaces. Propanal and hydrogen readily equilibrate with propanol via C-H and O-H addition steps to form surface propoxide intermediates and equilibrated propanal/propanol mixtures. Surface propoxides readily form via low energy paths involving a hydrogen addition to the electrophilic carbon center of the carbonyl of propanal or via a proton transfer from an adsorbed propanol to a vicinal propanal. The resulting propoxide withdraws electron density from the surface and behaves as a base catalyzing the activation of propanal and subsequent esterification and condensation reactions. These basic propoxides can readily abstract the acidic Cα-H of propanal to produce the CH3CH(-)CH2O* enolate, thus initiating aldol condensation. The enolate can subsequently react with a second adsorbed propanal to form a C-C bond and a ß-alkoxide alkanal intermediate. The ß-alkoxide alkanal can subsequently undergo facile hydride transfer to form the 2-formyl-3-pentanone intermediate that decarbonylates to give the 3-pentanone product. Cu is unique in that it rapidly catalyzes the decarbonylation of the C2n intermediates to form C2n-1 3-pentanone as the major product with very small yields of C2n products. This is likely due to the absence of Brønsted acid sites, present on metal oxide catalysts, that rapidly catalyze dehydration of the hemiacetal or hemiacetalate over decarbonylation. The basic surface propoxide that forms on Cu can also attack the carbonyl of a surface propanal to form propyl propionate. Theoretical results indicate that the rates for both aldol condensation and esterification are controlled by reactions between surface propoxide and propanal intermediates. In the condensation reaction, the alkoxide abstracts the weakly acidic hydrogen of the Cα-H of the adsorbed alkanal to form the surface enolate whereas in the esterification reaction the alkoxide nucleophilically attacks the carbonyl group of a vicinal bound alkanal. As both condensation and esterification involve reactions between the same two species in the rate-limiting step, they result in the same rate expression which is consistent with experimental results. The theoretical results indicate that the barriers between condensation and esterification are within 3 kJ mol-1 of one another with esterification being slightly more favored. Experimental results also report small differences in the activation barriers but suggest that condensation is slightly preferred.

5.
Psychiatry Res ; 334: 115816, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38412712

RESUMO

Non-suicidal self-injury (NSSI) is a significant public health problem, but there is no consistent evidence of its risk factors. One possibility is that there are subtypes NSSI that have different risk factors and clinical symptoms. In this review we evaluated the evidence of subtypes to determine if there were consistent subtypes of NSSI that emerged across studies. Four databases (Medline; Embase; PsycINFO; Web of Science) were searched to identify studies that used data-driven approaches and were published before November 9, 2022. There were 21 studies with 23 unique samples for review. Most of the included studies used NSSI symptoms or personal characteristics as the subtyping indicators, revealing 2-5 subtypes of NSSI. Variations in subtyping indicators, sample characteristics, and statistical methods may have contributed to the inconsistent number and characteristics of subtypes across studies. A new conceptual framework is proposed to integrate these diverse findings, highlighting the important roles of NSSI function and psychological pain in differentiating NSSI subtypes. This framework sheds light on the differences among self-injurers and offers insights for future endeavors to address the complexities of NSSI.


Assuntos
Comportamento Autodestrutivo , Humanos , Comportamento Autodestrutivo/psicologia , Fatores de Risco , Gerenciamento de Dados , Bases de Dados Factuais
6.
Environ Sci Technol ; 47(19): 11318-25, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23988277

RESUMO

Hydraulically fractured shale formations are being developed widely for oil and gas production. They could also represent an attractive repository for permanent geologic carbon sequestration. Shales have a low permeability, but they can adsorb an appreciable amount of CO2 on fracture surfaces. Here, a computational method is proposed for estimating the CO2 sequestration capacity of a fractured shale formation and it is applied to the Marcellus shale in the eastern United States. The model is based on historical and projected CH4 production along with published data and models for CH4/CO2 sorption equilibria and kinetics. The results suggest that the Marcellus shale alone could store between 10.4 and 18.4 Gt of CO2 between now and 2030, which represents more than 50% of total U.S. CO2 emissions from stationary sources over the same period. Other shale formations with comparable pressure-temperature conditions, such as Haynesville and Barnett, could provide significant additional storage capacity. The mass transfer kinetic results indicate that injection of CO2 would proceed several times faster than production of CH4. Additional considerations not included in this model could either reinforce (e.g., leveraging of existing extraction and monitoring infrastructure) or undermine (e.g., leakage or seismicity potential) this approach, but the sequestration capacity estimated here supports continued exploration into this pathway for producing carbon neutral energy.


Assuntos
Sequestro de Carbono , Metano/química , Dióxido de Carbono/química , Fenômenos Geológicos
7.
Environ Sci Technol ; 47(20): 11858-65, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24040744

RESUMO

Hydrated mineral surfaces in the environment are generally hydrophilic but in certain cases can strongly adhere CO2, which is largely nonpolar. This adhesion can significantly alter the wettability characteristics of the mineral surface and consequently influence capillary/residual trapping and other multiphase flow processes in porous media. Here, the conditions influencing adhesion between CO2 and homogeneous mineral surfaces were studied using static pendant contact angle measurements and captive advancing/receding tests. The prevalence of adhesion was sensitive to both surface roughness and aqueous chemistry. Adhesion was most widely observed on phlogopite mica, silica, and calcite surfaces with roughness on the order of ~10 nm. The incidence of adhesion increased with ionic strength and CO2 partial pressure. Adhesion was very rarely observed on surfaces equilibrated with brines containing strong acid or base. In advancing/receding contact angle measurements, adhesion could increase the contact angle by a factor of 3. These results support an emerging understanding of adhesion of, nonpolar nonaqueous phase fluids on mineral surfaces influenced by the properties of the electrical double layer in the aqueous phase film and surface functional groups between the mineral and CO2.


Assuntos
Dióxido de Carbono/química , Minerais/química , Água/química , Adesividade , Concentração Osmolar , Sais/química , Estresse Mecânico , Molhabilidade
8.
Sci Rep ; 13(1): 15395, 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37717092

RESUMO

Vital node discovery is a hotspot in network topology research. The key is using the Internet's routing characteristics to remove noisy paths and accurately describe the network topology. In this manuscript, a vital regional routing nodes discovery algorithm based on routing characteristics is proposed. We analyze the stability of multiple rounds of measurement results to overcome the single vantage point's path deviation. The unstable paths are eliminated from the regional network which is constructed through probing for target area, and the pruned topology is more in line with real routing rules. Finally, we weight the edge based on the actual network's routing characteristics and discover vital nodes in combination with the weighting degree. Unlike existing algorithms, the proposed algorithm reconstructs the network topology based on communication and transforms unweighted network connections into weighted connections. We can evaluate the node importance in a more realistic network structure. Experiments on the Internet measurement data (275 million probing results collected in 107 days) demonstrate that: the proposed algorithm outperforms four existing typical algorithms. Among 15 groups of comparison in 3 cities, our algorithm found more (or the same number) backbone nodes in 10 groups and found more (or the same number) national backbone nodes in 13 groups.

9.
Front Psychol ; 14: 1199285, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38274673

RESUMO

Introduction: Parenting and peer victimization (PV) are crucial for adolescent drinking. To further explore the cause of adolescent drinking, the present study investigated the role of PV and personal growth initiative (PGI) in the relationship between parental corporal punishment (PCP) and adolescent drinking. Methods: Present study build moderated mediation models to test the hypothesis, and detailed analysis of gender differences was conducted on the models. The data were collected in a cross-sectional questionnaire study with n = 1,007 adolescents (mean age = 13.16 years, 51.84% girls, n = 522). Results: Model analysis showed that: (1) PV totally mediated the relationship between PCP and adolescent girls' drinking behavior; (2) The positive association between PV and drinking was only significant for girls with low PGI. Discussion: These findings underscore the importance of the protective effect of a personality trait characterized by spontaneous self-promotion on adolescent girls' drinking.

10.
Front Psychol ; 13: 1032675, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36533059

RESUMO

Introduction: Having to adapt to a new environment with various other challenges while completing their studies, Chinese college students experience intense stress related to the study of the English language. However, there has been little research on the serial mediating mechanism of English-learning stress on English academic performance. Methods: Present study recruited 1130 undergraduate students to finish self-report online questionnaire to collect the information about their English-learning stress, academic anxiety and burnout, English academic performance and grit. We constructed a moderated serial mediation model to test the effect of academic anxiety and academic burnout and explored whether grit can restrict the decrease in academic performance caused by English-learning stress. Results: Results show that: (1) both academic anxiety and academic burnout mediate the relationship between English-learning stress and performance; (2) academic anxiety and academic burnout show a significant serial mediating role between academic pressure and English academic performance; and (3) grit significantly moderates the relationship between academic burnout and English academic performance. Discussion: These results lead us to believe that cultivating the grit of Chinese college students may be an effective way to improve the academic performance of those experiencing high English-learning stress.

11.
Front Psychol ; 13: 1038470, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36389463

RESUMO

Internet addiction (IA) is a growing social problem with negative mental and social outcomes; the present study examined whether rejection sensitivity mediates the relationship between interparental conflict and adolescent IA and the moderating role of school connectedness. One thousand and seven adolescents (51.84% females; Meanage = 13.17; SD = 0.69) anonymously completed questionnaires to assess interparental conflict, school connectedness, rejection sensitivity, IA, and demographic information. The model results showed that: (1) the positive association between interparental conflict and adolescent IA was partially mediated by rejection sensitivity; (2) this indirect link was moderated by the school connectedness and was stronger for adolescents with high school connectedness. The results provide support for the attachment theory that high interparental conflict could increase adolescents' rejection sensitivity, and high school connectedness plays a double-edged role that adolescents show more rejection sensitivity while reporting high interparental conflict and high school connectedness.

12.
Light Sci Appl ; 11(1): 168, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35650178

RESUMO

On-chip spatial mode operation, represented as mode-division multiplexing (MDM), can support high-capacity data communications and promise superior performance in various systems and numerous applications from optical sensing to nonlinear and quantum optics. However, the scalability of state-of-the-art mode manipulation techniques is significantly hindered not only by the particular mode-order-oriented design strategy but also by the inherent limitations of possibly achievable mode orders. Recently, metamaterials capable of providing subwavelength-scale control of optical wavefronts have emerged as an attractive alternative to manipulate guided modes with compact footprints and broadband functionalities. Herein, we propose a universal yet efficient design framework based on the topological metamaterial building block (BB), enabling the excitation of arbitrary high-order spatial modes in silicon waveguides. By simply programming the layout of multiple fully etched dielectric metamaterial perturbations with predefined mathematical formulas, arbitrary high-order mode conversion and mode exchange can be simultaneously realized with uniform and competitive performance. The extraordinary scalability of the metamaterial BB frame is experimentally benchmarked by a record high-order mode operator up to the twentieth. As a proof of conceptual application, an 8-mode MDM data transmission of 28-GBaud 16-QAM optical signals is also verified with an aggregate data rate of 813 Gb/s (7% FEC). This user-friendly metamaterial BB concept marks a quintessential breakthrough for comprehensive manipulation of spatial light on-chip by breaking the long-standing shackles on the scalability, which may open up fascinating opportunities for complex photonic functionalities previously inaccessible.

13.
Ann Palliat Med ; 10(8): 9184-9191, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34488404

RESUMO

BACKGROUND: This study aimed to investigate the distribution pattern of carbapenemases and evaluate their solitary contribution to carbapenem resistance. METHODS: One hundred and twelve isolates of Acinetobacter baumannii (A. baumannii) isolated from the intensive care unit (ICU) of a southern China tertiary hospital were identified, and antimicrobial susceptibility tests (ASTs) of these strains were determined. Common carbapenemases were detected and the distribution pattern of carbapenemases was analyzed. Logistic regression and general linear model analyzed were performed to identify the correlation between antimicrobial susceptibility and carbapenemase genes. RESULTS: These 112 strains were classified into a carbapenem-resistant A. baumannii (CRAB) group (71.7%) and a carbapenem-susceptible A. baumannii (CSAB) group (28.3%). Carbapenemase genes, including blaOXA-51-like (100.0%), blaOXA-23 (93.4%), ISAba1/blaOXA-51-like (27.5%), blaNDM-1 (8.8%), blaOXA-24 (2.2%) and blaOXA-58 (2.2%) were detected in CRAB strains, and no blaSIM, blaVIM and blaIMP gene in these 112 isolates. There was a statistically significant difference between CSAB and CRAB group in carrying blaOXA-23 (P<0.001) and ISAba1/blaOXA-51-like (P=0.024). CONCLUSIONS: A pattern of blaOXA-51-like (100.0%), blaOXA-23 (93.4%), blaNDM-1 (8.8%), blaOXA-24 (2.2%) and blaOXA-58 (2.2%) was detected in CRAB strains. BlaOXA-23-like and ISAba1/blaOXA-51-like complex might be more relevant to carbapenem resistance in A. baumannii. Harboring blaOXA-23-like and ISAba1/blaOXA-51-like complex might increase the possibility of resistance 2.16 times [risk ratio (RR): 2.16; 95% confidence interval (CI): 1.04-4.51] and 1.29 times (RR: 1.29; 95% CI: 1.07-1.56), respectively.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Infecções por Acinetobacter/tratamento farmacológico , Acinetobacter baumannii/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Proteínas de Bactérias , Humanos , Testes de Sensibilidade Microbiana , beta-Lactamases
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