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Photodissociation dynamics of H2O via the FÌ state at 111.5 nm were investigated using the high resolution H-atom Rydberg "tagging" time-of-flight (TOF) technique, in combination with the tunable vacuum ultraviolet free electron laser at the Dalian Coherent Light Source. The product translational energy distributions and angular distributions in both parallel and perpendicular directions were derived from the recorded TOF spectra. Based on these distributions, the quantum state distributions and angular anisotropy parameters of OH (X) and OH (A) products have been determined. For the OH (A) + H channel, highly rotationally excited OH (A) products have been observed. These products are ascribed to a fast direct dissociation on the BÌ1A1 state surface after multi-step internal conversions from the initial excited FÌ state to the BÌ state. While for the OH (X) + H channel, very highly rotationally excited OH (X) products with moderate vibrational excitation are revealed and attributed to the dissociation via a nonadiabatic pathway through the well-known two conical intersections between the BÌ-state and the XÌ-state surfaces.
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Cervical cancer (CC) stands as one of the most prevalent malignancies among females, and the examination of serum tumor markers(TMs) assumes paramount significance in both its diagnosis and treatment. This research delves into the potential of combining Surface-Enhanced Raman Spectroscopy (SERS) with Multivariate Statistical Analysis (MSA) to diagnose cervical cancer, coupled with the identification of prospective serum biomarkers. Serum samples were collected from 95 CC patients and 81 healthy subjects, with subsequent MSA employed to analyze the spectral data. The outcomes underscore the superior efficacy of Partial Least Squares Discriminant Analysis (PLS-DA) within the MSA framework, achieving predictive accuracy of 97.73 %, and exhibiting sensitivities and specificities of 100 % and 95.83 % respectively. Additionally, the PLS-DA model yields a Variable Importance in Projection (VIP) list, which, when coupled with the biochemical information of characteristic peaks, can be utilized for the screening of biomarkers. Here, the Random Forest (RF) model is introduced to aid in biomarker screening. The two findings demonstrate that the principal contributing features distinguishing cervical cancer Raman spectra from those of healthy individuals are located at 482, 623, 722, 956, 1093, and 1656 cm-1, primarily linked to serum components such as DNA, tyrosine, adenine, valine, D-mannose, and amide I. Predictive models are constructed for individual biomolecules, generating ROC curves. Remarkably, D-mannose of V (C-N) exhibited the highest performance, boasting an AUC value of 0.979. This suggests its potential as a serum biomarker for distinguishing cervical cancer from healthy subjects.
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Biomarcadores Tumorais , Análise Espectral Raman , Neoplasias do Colo do Útero , Humanos , Análise Espectral Raman/métodos , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/sangue , Feminino , Biomarcadores Tumorais/sangue , Análise Multivariada , Análise dos Mínimos Quadrados , Análise Discriminante , Adulto , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Nonsuicidal self-injury (NSSI) is a serious public health and clinical problem, particularly for adolescents, and may link to problematic smartphone use (PSU) and chronotype. This study examines the independent and interaction effects of PSU and chronotype on NSSI among adolescents and identified gender differences in these associations. METHODS: A total of 21,357 students aged 11-19 were recruited using stratified cluster sampling across five representative provinces in China and completed standard questionnaires to record details of PSU, chronotype, and NSSI. RESULTS: A total of 38.1 % of students reported having engaged in NSSI and 17.7 % had PSU. PSU and chronotype were significantly associated with NSSI among adolescents, and this relationship was stronger in females. Interaction analysis indicated that E-type and PSU were interactively associated with increased risks of NSSI. CONCLUSION: The findings suggest that E-type and PSU can increase the risk of NSSI both independently and interactively. Therefore, they should be considered in intervention programs for NSSI, especially for females.
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Comportamento Autodestrutivo , Smartphone , Feminino , Humanos , Adolescente , Cronotipo , Comportamento Autodestrutivo/epidemiologia , Inquéritos e Questionários , China/epidemiologiaRESUMO
It is a promising method to identify structural damage using bridge dynamic response under moving vehicle excitation, but the lack of accurate information about road roughness and vehicle parameters will lead to the failure of this method. The paper proposed a step-by-step EKF damage identification method, which transforms the inversion problem of unknown structural parameters under unknown loads (vehicle and road roughness) into two separate inversion problems: moving contact force identification and damage parameters identification. Firstly, the VBI model is converted into bridge vibration model under a moving contact force, and the moving contact force covering the information of road roughness and vehicle parameters can be calculated by EKF iteration. Secondly, the moving contact force identified in the first step is loaded on the bridge as a known condition, and the bridge damage problem is also solved by the EKF method. Numerical analyses of a simply-supported bridge under the moving vehicle are conducted to investigate the accuracy and efficiency of the proposed method. Effects of the vehicle speed, the damage cases, the measurement noise, and the roughness levels on the accuracy of the identification results are investigated. The results demonstrate the proposed algorithm is efficient and robust, and the algorithm can be developed into an effective tool for structural health monitoring of bridges.
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Algoritmos , VibraçãoRESUMO
BACKGROUND: Although previous studies have examined many predictors of suicidal behaviors. However, little is known for childhood physical abuse (CPA) and aggression, which are prevalent among adolescents. This study aimed to explore association between CPA and suicidal behaviors, and the potential mediating role of aggression. METHOD: A total of 16,111 students graded 7 to 12 were recruited using a stratified cluster sampling across five representative provinces in China. Conflict Tactics Scale-Parents to Child (CTS-PC) and Buss and Warren's Aggression Questionnaire (BWAQ) were used to measure CPA and aggression, respectively. RESULTS: During the last year, 16.0 % of adolescents reported suicidal behaviors. Specifically, 7.9 % were suicide ideators, 4.6 % were planners, and 3.5 % were attempters. The prevalence of CPA in mild, moderate, and severe was 15.7 %, 26.9 %, and 4.4 %, respectively. Multinomial logistic regression indicated that moderate and severe CPA and overall aggression were associated with suicide ideators, planners, and attempters. In five sub-types of aggression, only hostility was significantly associated with all three suicidal behaviors. Structural equation modelling showed that aggression partially mediate the relationship between CPA and suicidal behaviors. The mediation proportion of overall aggression, physical aggression, verbal aggression, anger, hostility, and indirect aggression were 27.2 %, 22.4 %, 5.2 %, 14.2 %, 23.5 %, and 12.1 %, respectively. LIMITATIONS: Cross-sectional design, self-reported questionnaire, and no other forms of childhood maltreatment. CONCLUSIONS: CPA is a critical risk factor of suicidal behaviors among Chinese adolescents and aggression is a mediator between CPA and suicidal behaviors. Targeted suicide prevention should focus on those adolescents who report CPA and aggression, especially for hostility.
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Maus-Tratos Infantis , Ideação Suicida , Adolescente , Agressão , Criança , China/epidemiologia , Estudos Transversais , Humanos , Abuso Físico , Fatores de Risco , Tentativa de SuicídioRESUMO
BACKGROUND: Previous studies have reported that Internet addiction (IA) is an important predictor of aggression. However, little is known whether aggression is a risk factor of IA. This study aims to explore whether IA can predict total and sub-types of aggression, whether aggression also can predict IA, and the potential sex difference. METHOD: A total of 15,977 adolescents aged 12 to 18 were recruited though a stratified cluster sampling across five representative provinces in mainland of China. Young's Internet Addiction Test (IAT) and Buss and Warren's Aggression Questionnaire (BWAQ) were used to measure IA and aggression, respectively. RESULTS: The prevalence of IA and total aggression was 16.8 % and 25.0 %, respectively. Binary logistic regression analysis indicated that IAT score was significantly associated with total and five sub-types of aggression (P < 0.001). However, scores of physical aggression, hostility, and indirect aggression were positively associated with IA (P < 0.001), while verbal aggression and anger were not significant (P > 0.05). Moreover, the interaction of sex and IA was significant for aggression. Specifically, females with IA had higher risks of anger and indirect aggression but had lower risks of physical and verbal aggression compared to males with IA. LIMITATIONS: Cross-sectional design, self-reported information, and only Chinese rural adolescents. CONCLUSIONS: IA is a strong risk factor of total and five sub-types of aggression, while not all sub-types of aggression are predictors of IA. Prevention programs for adolescents' IA and aggression should consider different aggression sub-types and sex.
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Comportamento Aditivo , Transtorno de Adição à Internet , Adolescente , Agressão , Comportamento Aditivo/epidemiologia , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Internet , Masculino , Caracteres Sexuais , Inquéritos e QuestionáriosRESUMO
The phylogeographic structure of the land snail Camaena cicatricosa was analyzed in this study based on mitochondrial gene (COI and 16srRNA, mt DNA) and internal transcribed spacer (ITS2) sequences in 347 individuals. This snail is the vector of the zoonotic food-borne parasite Angiostrongylus cantonensis and one of the main harmful snails distributed exclusively in China. The results revealed significant fixation indices of genetic differentiation and high gene flow between most populations except several populations. An isolation-by-distance test showed no significant correlation between genetic distance and geographical distance among C. cicatricosa populations, which suggested that gene flow was not restricted by distance. The levels of haplotype and nucleotide diversity of C. cicatricosa were generally high, except those in some special populations, according to the mt DNA and ITS2 data. Furthermore, the phylogenetic trees and asteroid networks of haplotypes indicated nonobvious genetic structure, the same as results got based on the synonymous and non synonymous sites of 347 sequences of the COI gene. All lines of evidence indicated that climatic changes and geographical and human barriers do not substantially affect the current population structure and distribution of the investigated snails.
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DNA Intergênico/genética , DNA Mitocondrial/genética , Genética Populacional , Caramujos/genética , Animais , China , Estruturas Genéticas , Variação Genética/genética , Haplótipos/genética , Humanos , Filogeografia , RNA Ribossômico 16S/genéticaRESUMO
The land snail Cernuella virgata (da Costa, 1778) is widely considered as a pest to be quarantined in most countries. In this study, the complete mitochondrial genome of Cernuella virgata is published. The mitochondrial genome has a length of 14,147 bp a DNA base composition of 29.07% A, 36.88% T, 15.59% C and 18.46% G, encoding 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes and two ribosomal RNA (rRNA) genes. The complete nucleotide composition was biased toward adenine and thymine, A+T accounting for 69.80%. Nine PCGs and 14 tRNA genes are encoded on the J strand, and the other four PCGs and eight tRNA genes are encoded on the N strand. The genome also includes 16 intergenic spacers. All PCGs start strictly with ATN, and have conventional stop codons (TAA and TAG). All tRNAs fold into the classic cloverleaf structure, except tRNA(Arg) , tRNA(Ser(UCN)) , tRNA(Ser(AGN)) and tRNA(Pro) . The first three lack the dihydrouridine arm while the last lacks the TψC arm. There are 502 bp long noncoding regions and 418bp long gene overlaps in the whole mitochondrial genome, accounting for 3.54% and 2.95% of the total length respectively. Phylogenetic analyses based on the sequences of the protein coding genes revealed a sister group relationship between the Hygromiidae and the Helicidae.
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The camaenid land snail genus Camaena is widely distributed throughout Southeast Asia. Thirteen species are found in China alone. Among these, Camaena cicatricosa (Müller, 1774) is the most widely distributed species, including four subspecies, Camaena cicatricosa ducalis (Ancey, 1885), Camaena cicatricosa inflata (Möllendorff, 1885), Camaena cicatricosa obtecta (Fischer, 1898) and Camaena cicatricosa connectens (Dautzenberg & Fischer, 1906). The systematics of these taxa is revised herein based on comparative shell morphology and anatomy as well as analyses of DNA sequences of two mitochondrial genes (COI, 16S rRNA) and one nuclear marker, ITS2. We found that all subspecies form well-supported clades in a molecular phylogeny and are well-differentiated from each other by genetic distances that are consistent with amounts of interspecific differentiation. In addition, they clearly differ from each other in reproductive features. Based on these observations, we elevate all four subspecies to the rank of full species. Moreover, based on morphological and mitochdondrial differentiation, we describe a new species, Camaena poyuensis sp. n. from Guangxi, China. The new species conspicuously differs from its sibling species Camaena cicatricosa in having a larger and more depressed shell, a completely covered umbilicus, more or less purplish peristome, an obtuse angle at the junction of the basal and columellar lip, longer pedunculus of the bursa copulatrix, thicker epiphallus and penis, and short conic verge. Previous named species are also redescribed on their shell and anatomical characters, because the original descriptions are uninformative.