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1.
Sci Total Environ ; 946: 174362, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38955280

RESUMO

Niobium has been considered to be enriched in high-Al-Ga in north China coal and coal-hosted Nb(Ta)-Zr(Hf)-REY-Ga polymetallic deposits in the southwestern region of China. However, modes of occurrence and influencing factors of Nb in Al-Ga-rich coal in North China are rarely reported. This study investigated the distribution characteristics of Nb in the No.6 high-Al-Ga coal of the Jungar Coalfield in North China. The in-situ Nb concentration of selected minerals, including kaolinite, Ti-oxides, boehmite, and zircon, is further quantitatively characterized based on multiscale in-situ elemental analyses, including SEM-EDS and LA-ICP-MS spot and mapping analyses. The results showed that Nb is rich in the tonstein and mudstone partings among bulk samples and is highly concentrated in Ti-oxides, followed by zircon among the minerals. A certain amount of Nb is associated with kaolinite and boehmite with different modes of occurrence: vermicular kaolinite (65.94 ppm) > clastic kaolinite (25.43 ppm) > altered K-bearing kaolinite (18.11 ppm) > cryptocrystalline kaolinite (17.03 ppm) > clastic boehmite (9.08 ppm) > cryptocrystalline boehmite (7.97 ppm). The Nb-Nb/Ta and Zr/Hf-Nb/Ta ratios suggest that the primary source of Nb in the No.6 coal is the altered felsic volcanic ash and bauxite deposit. The high-Fe concentration in Ti-bearing minerals indicates that anatase may originate from the alteration of ilmenite with a process of Fe depletion and Nb enrichment. The enrichment of Nb in coal is attributed to the substitution of Nb for Ti in isomorphism in all Ti-oxides, high-Ti, and Ti-bearing minerals.

2.
Opt Express ; 32(2): 2539-2553, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297780

RESUMO

Synthetic aperture Ladar (SAL) is an extension of synthetic aperture technology in the optical frequency band. Owing to the short wavelength of lasers, the system has high-resolution, high-data-rate, and refined imaging capabilities, which has potential in high-resolution observation fields such as ground observation and space target observation. However, the short wavelength of lasers also makes SAL severely sensitive to vibrations even on the micron order which cause azimuth defocusing and range cell migration. To address this problem, we establish a de-chirp signal model under vibration environment, and propose a vibration error estimation and compensation method using triangular interferometric signals. According to the symmetrical characteristics of triangular frequency modulated continuous wave (T-FMCW) and the time-frequency information introduced by the azimuthal vibration phase, we use a two-stage interferometry method to estimate instantaneous frequency introduced by the vibration errors that cause range cell migration. For the scenarios without obvious range cell migration, we use a one-stage interferometry method to estimate the instantaneous frequency. Subsequently, we establish a vibration compensation filter using the estimated instantaneous frequency to compensate for the vibration errors. We use two experiments to verify the effectiveness and superiority of the proposed method. The results show that the proposed method effectively eliminates range cell migration and azimuthal phase errors introduced by vibration errors, producing SAL imaging results with higher resolution than the conventional spectral correlation method.

3.
ACS Omega ; 7(16): 13557-13576, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35559164

RESUMO

The geochemical characteristics of trace elements in Carboniferous-Permian coal and gangue in the Yangcheng mining area in Qinshui Basin, a large Carboniferous-Permian coalfield in China, were studied by inductively coupled plasma mass spectrometry (ICP-MS), and their geological significance was discussed. The results show that the content of trace elements in late Paleozoic coal in the Yangcheng mining area is depleted, except for slight enrichment of Li. Except for Li, Co, and Mo, the content of trace elements in the gangue was higher than that in the coal. The content of rare earth elements in gangue (324.28 µg/g) is much higher than that in coal (66.22 µg/g). The rare earth elements (REY) content in the coal in the Shanxi Formation (93.88 µg/g) is slightly higher than that in the Taiyuan Formation (66.19 µg/g). The mean values of δEu and δCe are 0.71 and 0.94, respectively. Except for the YIC3-1 curve of the Shanxi Formation, which is obviously convex and shows a positive Eu anomaly, the REY distribution patterns of the remaining samples are similar, showing the characteristics of light rare earth elements (LREY) enrichment and heavy rare earth elements (HREY) depletion. The Carboniferous-Permian coal-forming environment in the Yangcheng mining area is in an anoxic-reducing, warm, humid, and brackish water sedimentary environment. The paleosalinity and paleotemperature of the Shanxi coal formation are higher than those of the Taiyuan Formation, which is more inclined to be a reducing environment. The provenance of Carboniferous-Permian coal in the Yangcheng mining area is mainly derived from acidic sedimentary rocks of the upper crust of the post-Archaean, mixed with a small amount of granite, alkaline basalt, and oceanic tholeiite. The tectonic setting of the provenance is mainly an active continental margin related to a continental island arc mixed with an oceanic island arc and a passive continental margin tectonic setting.

4.
ACS Omega ; 6(27): 17660-17673, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34278151

RESUMO

The Qinshui basin is an important coal-accumulating basin in China, and its Late Paleozoic coal is an important source rock of coalbed methane in the basin. Its thermal evolution and gas generation characteristics determined the grade of coalbed methane resources, especially the coal measure free gas resources in the basin. Late Paleozoic coal samples were collected for organic geochemical analysis, a high-volatile bituminous coal was used for hydrous pyrolysis, to propose the thermal evolution characteristics, gas generation characteristics, thermal evolution, and free gas accumulation model, and the Ordos Basin is compared. The results show that the variation trends of various geochemical parameters are different with the increase in R o. Hydrous pyrolysis shows that the gas production potential of coal is excellent. The gases produced consist mainly of CH4, C2-, CO2, and H2. C2- is produced only before the simulated temperature of 550 °C, and oil is produced only before the temperature of 500 °C. The thermal evolution stages can be divided into the immature stage, symbiosis stage, wet gas stage, and dry gas stage, and the symbiosis stage can be divided into the preliminary stage and mainly gas stage. R o, T max, (2+3)MP/(1+9)MP, saturated+arene, V daf, and H/C can be used as indicators of the thermal evolution stages. On the plane, the distribution of thermal evolution stages of the Shanxi Formation and the Taiyuan Formation is very alike. The gas generating strength of the Taiyuan Formation is higher than that of the Shanxi Formation. The gas generating strength in the north of the Taiyuan Formation is higher, while that in the south of the Shanxi Formation is higher. The second gas generation stage has a good spatio-temporal configuration relationship with accumulation factors, and the gas production is large, which is beneficial to the enrichment of the coal measure free gas resources. Relatively, the Ordos Basin has better prospects for exploration and development.

5.
BMC Med Educ ; 21(1): 183, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33766012

RESUMO

BACKGROUND: The undergraduate program of psychiatry has been widely established in recent years to improve the education and recruitment of psychiatrists in China. We aim to investigate the career choice of medical students majoring in psychiatry in China and the influential factors. METHOD: This multicenter study was conducted in 26 medical schools in China from May to October of 2019. Participants included 4610 medical students majoring in psychiatry and 3857 medical students majoring in clinical medicine. Multivariable logistic regression was used to investigate the influential factors of students' choices of psychiatry at matriculation and as a career. RESULTS: 44.08% of psychiatry majored students gave psychiatry as a first choice at matriculation, and 56.67% of them would choose psychiatry as a career, which was in sharp contrast to the proportion of clinical medicine majored students who would choose psychiatry as a career (0.69%). Personal interest (59.61%), suggestions from family members (27.96%), and experiencing mental problems (23.19%) were main reasons for choosing psychiatry major at matriculation. Personal interest (odds ratio [OR] = 2.12, 95% confidence interval [CI] = 1.87-2.40), experiencing a psychiatry clerkship (OR = 1.99, 95% CI = 1.28-3.08), being female (OR = 1.50, 95% CI = 1.30-1.68), experiencing mental problems (OR = 1.33, 95% CI = 1.28-1.56), and suggestions from family members (OR = 1.25, 95% CI = 1.08-1.46) correlated positively with students' choice of psychiatry as career. Students who lacked psychiatry knowledge (OR = 0.49, 95% CI = 0.29-0.85) or chose psychiatry because of lower admission scores (OR = 0.80, 95% CI = 0.63-0.97) were less likely to choose psychiatry as a career. CONCLUSION: More than half of psychiatry majored medical school students planned to choose psychiatry as their career, whereas very few students in the clinic medicine major would make this choice. Increasing students' interest in psychiatry, strengthening psychiatry clerkships, and popularizing psychiatric knowledge are modifiable factors to increase the psychiatry career intention. The extent to which medical students' attitudes toward psychiatry can be changed through medical school education and greater exposure to psychiatry will need further investigation.


Assuntos
Psiquiatria , Estudantes de Medicina , Escolha da Profissão , China , Feminino , Humanos , Psiquiatria/educação , Faculdades de Medicina , Inquéritos e Questionários
6.
Front Psychiatry ; 11: 481, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32581867

RESUMO

Anhedonia, the loss or decline of the ability to enjoy pleasure, is an important clinical characteristic of schizophrenia. Schizotypal traits refer to the appearance of subclinical symptoms of schizophrenia across normal people. Still, few studies have investigated chemosensory anhedonia in schizophrenia patients and schizotypy individuals. Seventy-one schizophrenia patients (SCZ), 162 schizotypy individuals (SCT) as selected by the Schizotypal Personality Questionnaire (SPQ), and 182 healthy controls (HC) participated in our study. We used the Positive and Negative Syndrome Scale (PANSS) to measure the clinical symptoms of schizophrenia patients. All participants completed the Chemosensory Pleasure Scale (CPS), which was used to assess participants' smell and taste hedonic capacities. We found that the three groups differed in chemosensory anhedonia. The SCZ group presented more severe chemosensory anhedonia than the SCT group, and the SCT group presented more severe chemosensory anhedonia than the HC group. We also found that chemosensory hedonic capacity was negatively correlated with negative schizotypal traits in the SCT group. Our results suggested that chemosensory anhedonia is an important characteristic of schizophrenia spectrum disorders.

7.
Front Psychol ; 11: 493, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32372994

RESUMO

Introduction: Previous studies have found that schizotypy can predict suicide, and that meaningfulness has influential effects on suicidality in the general population. However, it is still not clear whether meaningfulness is associated with suicidality in individuals with schizotypy. The aim of this study was to assess the mediating effects of meaningfulness in the relationship between schizotypy and suicidality. Method: We recruited 2,615 university students (including undergraduates and postgraduates; mean age = 18.35, SD = 0.81; males, 39%) to participate in our study, and used the Meaningful Life Measure (Chinese, revised) to assess their experiences of meaningfulness, the Suicidal Behaviors Questionnaire (Chinese version) to evaluate participants' suicidal thoughts and attempts, and the Schizotypal Personality Questionnaire to examine their personal schizotypal traits. Results: Meaningfulness was found to be inversely related to the other two factors, and schizotypy was positively associated with suicidality. The correlation between schizotypy and suicidality was reduced when meaningfulness was included, which may suggest that meaningfulness can partly mediate this relationship, accounting for 55.47% of the association. Conclusions: Prior research has suggested that assessing meaningfulness could provide more detailed information about suicide risk in individuals with schizotypy. Our study found that improving perceptions of meaningfulness can be an effective intervention in reducing suicide risk among people with schizotypy.

8.
Chem Senses ; 44(7): 457-464, 2019 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-31201424

RESUMO

Anhedonia, or the inability to experience pleasure, is a key clinical feature of many mental disorders such as depression and schizophrenia. Although various valid measurements of anhedonia and pleasure experience exist, no scales exist that quantify smell and taste pleasure experiences. The Chemosensory Pleasure Scale (CPS) was therefore designed to assess the hedonic capacity for smell and taste pleasure. We examined the reliability and validity of the CPS in our study. First, we conducted exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) to identify and examine the structure of the CPS. Second, the CPS's validity and test-retest stability were investigated. The CPS was correlated with other measurements of anhedonia and pleasure experience. Furthermore, the empirical validity of CPS was also examined in our study. The results indicated that the CPS is a reliable and valid measure for assessing an individual's hedonic capacity for smell and taste pleasure in nonclinical samples. Further application of the CPS for various populations is also discussed herein, especially for patients with mental disorders such as depression, schizophrenia, and autism.


Assuntos
Prazer , Olfato , Paladar , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
9.
Mol Med Rep ; 19(4): 2537-2550, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30720084

RESUMO

Earthworms are useful indicator organisms of soil health and Eisenia fetida have been extensively used as test organisms in ecotoxicological studies. In order to gain insight into the gene expression profiles associated with physiological functions of earthworms, a full­length enriched cDNA library of the Eisenia fetida genome was successfully constructed using Switching Mechanism at 5'End of RNA Template technology. Construction of a cDNA library and analysis of Expressed Sequence Tags (ESTs) are efficient approaches for collecting genomic information and identifying genes important for a given biological process. Furthermore, analysis of the expression abundance of ESTs was performed with the aim of providing genetic and transcriptomic information on the development and regenerative process of earthworms. Phrep and Crossmatch were used to process EST data and a total of 1,140 high­quality EST sequences were determined by sequencing random cDNA clones from the library. Clustering analysis of sequences revealed a total of 593 unique sequences including 225 contiguous and 368 singleton sequences. Basic Local Alignment Search Tool analysis against the Kyoto Encyclopedia of Genes and Genomes database resulted in 593 significant hits (P­value <1x10­8), of which 168 were annotated through Gene Ontology analysis. The STRING database was used to determine relationships among the 168 ESTs, identifying associated genes involved in protein­protein interactions and gene expression regulation. Based on nucleic acid and protein sequence homology, the mutual relationships between 287 genes could be obtained, which identified a portion of the ESTs as known genes. The present study reports on the construction of a high­quality cDNA library representative of adult earthworms, on a preliminary analysis of ESTs and on a putative functional analysis of ESTs. The present study is expected to enhance our understanding of the molecular basis underlying the biological development of earthworms.


Assuntos
Etiquetas de Sequências Expressas , Biblioteca Gênica , Oligoquetos/genética , Análise de Sequência de DNA , Animais , Biologia Computacional/métodos , Ontologia Genética , Anotação de Sequência Molecular
12.
Saudi Med J ; 32(1): 15-22, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21212910

RESUMO

OBJECTIVE: To study the synthesis of 131iodine (I) labeled histamine-indomethacin (His-IN), its in vivo distribution in Lewis-bearing mice, and its effects on suppression of Lewis lung cancer growth and induction of apoptosis. METHODS: The present study was carried out in the Experimental Research Center, Sheng Jing Hospital of China Medical University Hospital, Shenyang China between December 2008 and October 2009. Chemical synthesis of His-IN was carried out. Ninety-five C57 mice were allocated into 12 groups, and a series of experiments including the in vivo biological distribution of 131I-His-IN in C57 mice bearing Lewis lung cancer was explored, and the therapeutic effects of IN and 131I-His-IN in lung cancer-bearing mice were assessed through tumor suppression experiments, flow cytometry, and detection of tumor necrosis factor. RESULTS: The 131I-His-IN radionuclide count ratio of the tumor site and surrounding region significantly increased with time, namely, the retention time of 131I-His-IN radionuclide was longer in the tumor site. A 3.0 mg/kg and 3.5 mg/kg 131I-His-IN, as well as 3.0 mg/kg and 3.5 mg/kg IN all had tumor suppression and apoptosis induction effects on tumors, among which the 3.5 mg/kg 131I-His-IN group had significant differences compared with all other groups. CONCLUSION: The 131I-His-IN not only retains the tumor-affinity property of IN, the synergistic effect of these 2 also enhances the tumor suppression and pro-apoptotic function.


Assuntos
Carcinoma Pulmonar de Lewis/metabolismo , Radioisótopos do Iodo/farmacocinética , Neoplasias Pulmonares/metabolismo , Animais , Apoptose/efeitos dos fármacos , Cromatografia em Camada Fina , Sinergismo Farmacológico , Citometria de Fluxo , Histamina/farmacocinética , Masculino , Camundongos , Ratos , Ratos Endogâmicos Lew , Fator de Necrose Tumoral alfa/análise
14.
Nan Fang Yi Ke Da Xue Xue Bao ; 27(4): 482-4, 2007 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-17545038

RESUMO

OBJECTIVE: To compare the differences in mental health state and psychological capacities between Chinese college students with and without siblings. METHODS: The psychological status and capacities were evaluated with SCL-90, the Self-Esteem Scale, Spheres of Control Scale, Security Questionnaire and Cattell 16-PF Questionnaire in 427 college students, and among the students who presented valid responses, 139 with and 139 without siblings were selected for this comparative study. RESULTS: The total score and average score of SCL-90 in college students without siblings were significantly lower than those in students with siblings (P<0.05); the scores of factors C, E, and F of 16-PF were significantly higher but the score of factor O significantly lower in the former group (P<0.05). The scores of certainty in control, interpersonal security and total score of security were significantly higher in the students without siblings (P<0.01). CONCLUSION: The mental health state and some of the psychological capacities are generally better in college students with siblings than in those without siblings.


Assuntos
Saúde Mental , Irmãos , Estudantes/psicologia , Humanos , Inquéritos e Questionários , Universidades , Adulto Jovem
15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-268098

RESUMO

<p><b>OBJECTIVE</b>To compare the differences in mental health state and psychological capacities between Chinese college students with and without siblings.</p><p><b>METHODS</b>The psychological status and capacities were evaluated with SCL-90, the Self-Esteem Scale, Spheres of Control Scale, Security Questionnaire and Cattell 16-PF Questionnaire in 427 college students, and among the students who presented valid responses, 139 with and 139 without siblings were selected for this comparative study.</p><p><b>RESULTS</b>The total score and average score of SCL-90 in college students without siblings were significantly lower than those in students with siblings (P<0.05); the scores of factors C, E, and F of 16-PF were significantly higher but the score of factor O significantly lower in the former group (P<0.05). The scores of certainty in control, interpersonal security and total score of security were significantly higher in the students without siblings (P<0.01).</p><p><b>CONCLUSION</b>The mental health state and some of the psychological capacities are generally better in college students with siblings than in those without siblings.</p>


Assuntos
Humanos , Adulto Jovem , Saúde Mental , Irmãos , Estudantes , Psicologia , Inquéritos e Questionários , Universidades
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