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1.
Science ; 383(6680): 305-311, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38236973

RESUMEN

On 6 February 2023, two large earthquakes (moment magnitude 7.8 and 7.6) shocked a vast area of southeastern Türkiye and northern Syria, leading to heavy casualties and economic loss. To investigate the rupture process over multiple fault segments, we performed a comprehensive analysis of local seismic and geodetic data and determined supershear ruptures on the initial branch and the Pazarcik and Erkenek segments and subshear ruptures on the Amanos segment of event 1. The bilateral rupture of event 2 also presents distinct sub- and supershear velocities. The dynamic stress of the branch fault rupture triggered the Pazarcik segment initial rupture at a point 9 kilometers west of the junction of these two faults, boosting the supershear rupture of the Pazarcik segment of the main fault. The geometry and prestress level of multiple segments controlled the rupture behaviors and influenced the ground shaking intensity.

2.
PLoS One ; 18(1): e0279879, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36656818

RESUMEN

The current epidemiological status of the new coronary pneumonia epidemic in China is being explored to prevent and control the localized dissemination of aggregated outbreaks. This study analyzed the characteristics of new outbreaks of coronavirus disease 2019 (COVID-19) at three stages of aggregated outbreaks in Jilin Province, China, to provide a reference for the prevention and control of aggregated outbreaks. Case information were collected from all patients in Jilin Province from January 12, 2020 to the present. The epidemic was divided into three stages according to the time of onset. The first stage comprised 97 cases reported from January 12, 2020 to February 19, 2020, during which 17 aggregated outbreaks occurred. The second comprised 43 cases reported from April 25, 2020 and May 23, 2020, involving one aggregated outbreak. The third comprised 435 cases reported on January 10, 2021 and February 9, 2021, involving one aggregated outbreak. The relationship between aggregated and non-aggregated cases in the first phase of the outbreak and the difference between imported and local cases during the aggregated outbreak were assess using statistical analysis, and the differences in the baseline information between the three phases were analyzed. The incubation periods of the three phases were 10 days, 8 days, and 5 days. The number of aggregated epidemic events in Jilin Province tended to increase and then decrease over time. The clustered events in Jilin Province were divided into four categories: household contact (14 times, 51 cases); household contact and public places (one time, three cases); household contact, public places, and gatherings (one time, six cases); and household contact, public places, gatherings, and work (three times, 495 cases). Clustered events occurred mainly between January 22, 2020, and February 4, 2020. Among all cases in the first phase of the outbreak, the method of detection and the time from diagnosis to discharge were longer in aggregated cases than in non-aggregated cases, and that the source of infection and renewal cases were more frequent and more likely to be detected in the outpatient clinics during aggregated outbreaks than the imported cases. The second phase of the epidemic showed significant spatial variability (Moran's I<0, P<0.05). The third stage of the epidemic occurred in a higher proportion of individuals aged 50-90 years and within a shorter incubation period compared with the first two stages. The current focus of prevention and control of the COVID-19 epidemic in Jilin Province is to strictly implement the restrictions on gatherings and to perform timely screening and isolation of close contacts of infectious sources while strengthening the supervision of the inflow of people from outside the region. Simultaneously, more targeted prevention and control measures can be implemented for different age groups and occupations.


Asunto(s)
COVID-19 , Epidemias , Humanos , COVID-19/epidemiología , SARS-CoV-2 , China/epidemiología , Brotes de Enfermedades/prevención & control
3.
Proc Natl Acad Sci U S A ; 119(23): e2116445119, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-35658079

RESUMEN

The deformation mode of the Tibetan Plateau is of crucial importance for understanding its construction and extrusion processes, as well as for the assessment of regional earthquake potential. Block motion and viscous flow models have been proposed to describe the deformation field but are not fully supported by modern geophysical observations. The 2021 Mw 7.4 Maduo earthquake, which occurred inside the Songpan-Ganzi terrane (SGT) in central-east Tibet, provides a chance to evaluate the associated deformation mode of the region. We conduct a joint inversion for this earthquake and resolve a bilateral rupture process, which is characterized by super- and subshear rupture velocities, respectively. We interpret this distinct rupture behavior to be the result of the respective slip concentration depths of the two ruptured segments. We analyze geological, seismic, and geodetic evidence and find that the SGT upper crust shows distributed shear deformation and distinct transverse anisotropy, which are associated with folded structures originating from compression of the paleo-Tethys ocean accretional prism realigned by following shear deformation. The SGT receives lateral shear loading from its NS boundary and accommodates a right-step sinistral motion across the terrane boundary faults. The unique tectonic setting of the SGT defines locations and behaviors of internal faulting and strong earthquakes such as the 2021 Maduo earthquake, with the latter occurring on slow-moving faults at intervals of several thousands of years.

4.
BMC Infect Dis ; 21(1): 245, 2021 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-33676420

RESUMEN

BACKGROUND: Based on differences in populations and prevention and control measures, the spread of new coronary pneumonia in different countries and regions also differs. This study aimed to calculate the transmissibility of coronavirus disease 2019 (COVID-19), and to evaluate the effectiveness of measures to control the disease in Jilin Province, China. METHODS: The data of reported COVID-19 cases were collected, including imported and local cases from Jilin Province as of March 14, 2019. A Susceptible-Exposed-Infectious-Asymptomatic-Recovered/Removed (SEIAR) model was developed to fit the data, and the effective reproduction number (Reff) was calculated at different stages in the province. Finally, the effectiveness of the measures was assessed. RESULTS: A total of 97 COVID-19 infections were reported in Jilin Province, among which 45 were imported infections (including one asymptomatic infection) and 52 were local infections (including three asymptomatic infections). The model fit the reported data well (R2 = 0.593, P < 0.001). The Reff of COVID-19 before and after February 1, 2020 was 1.64 and 0.05, respectively. Without the intervention taken on February 1, 2020, the predicted cases would have reached a peak of 177,011 on October 22, 2020 (284 days from the first case). The projected number of cases until the end of the outbreak (on October 9, 2021) would have been 17,129,367, with a total attack rate of 63.66%. Based on the comparison between the predicted incidence of the model and the actual incidence, the comprehensive intervention measures implemented in Jilin Province on February 1 reduced the incidence of cases by 99.99%. Therefore, according to the current measures and implementation efforts, Jilin Province can achieve good control of the virus's spread. CONCLUSIONS: COVID-19 has a moderate transmissibility in Jilin Province, China. The interventions implemented in the province had proven effective; increasing social distancing and a rapid response by the prevention and control system will help control the spread of the disease.


Asunto(s)
Número Básico de Reproducción , COVID-19 , Control de Enfermedades Transmisibles , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , COVID-19/epidemiología , COVID-19/prevención & control , COVID-19/transmisión , China/epidemiología , Control de Enfermedades Transmisibles/métodos , Control de Enfermedades Transmisibles/organización & administración , Control de Enfermedades Transmisibles/normas , Humanos , Incidencia , SARS-CoV-2/aislamiento & purificación
5.
PeerJ ; 7: e7327, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31346501

RESUMEN

BACKGROUND: Schizophrenia (SCZ) is a complex and severe mental illness. There is a lack of effective biomarkers for SCZ diagnosis. The aim of this study was to explore the possibility of using serum peptides for the diagnosis of SCZ as well as analyze the association of variants in genes coding for these peptides and SCZ. METHODS: After bead-based fractionation, the matrix-assisted laser desorption ionization/time-of-flight mass spectrometry technique was used to identify peptides that showed different expressions between 166 SCZ patients and 201 healthy controls. Differentially expressed peptides were verified in a second set of samples (81 SCZ patients and 103 healthy controls). The association of SCZ and three tagSNPs selected in genes coding for differentially expressed peptides was performed in 1,126 SCZ patients and 1,168 controls. RESULTS: The expression level of peptides with m/z 1,945.07 was significant lower in SCZ patients than in healthy controls (P < 0.000001). The peptide with m/z 1,945.07 was confirmed to be a fragment of Kininogen-1. In the verification tests, Kininogen-1 had a sensitivity of 95.1% and a specificity of 97.1% in SCZ prediction. Among the three tagSNPs (rs13037490, rs2983639, rs2983640) selected in the Cystatin 9 gene (CST9) which encodes peptides including Kininogen-1, tagSNP rs2983640 had its genotype distributions significantly different between SCZ patients and controls under different genetic models (P < 0.05). Haplotypes CG (rs2983639-rs2983640) and TCG (rs13037490-rs2983639-rs2983640) were significantly associated with SCZ (CG: OR = 1.21, 95% CI [1.02-1.44], P = 0.032; TCG: OR = 24.85, 95% CI [5.98-103.17], P < 0.0001). CONCLUSIONS: The present study demonstrated that SCZ patients had decreased expression of Kininogen-1 and genetic variants in Kininogen-1 coding gene CST9 were significantly associated with SCZ. The findings from both protein and genetic association studies suggest that Kininogen-1 could be a biomarker of SCZ.

6.
Open Access Maced J Med Sci ; 7(9): 1436-1439, 2019 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-31198450

RESUMEN

AIM: To investigate the relationship between the polymorphism of related gene loci of miRNAs regulated fibrinopeptide A and schizophrenia. Lay the foundation for the aetiology of schizophrenia. METHODS: Adapt to the phase match of sex and age case-control study, a total of 513 Chinese Han patients with schizophrenia were selected as the case group, 513 normal healthy persons as a control group. Obtaining SNPs information of the FGA gene by querying the dbSNP database, and reference HapMap database included SNPs site frequency information for screening. The frequency distributions of SNPs were genotyped by iMLDR® SNP detection technology. Two SNPs (pre-hsa-miR-605rs2043556 T>C, pre-hsa-miR-499a/pre-hsa-miR-499brs4909237 T < C) were analyzed to demonstrate their association with susceptibility to schizophrenia. RESULTS: There were no significant differences between patients and controls in genotype and allele distribution of SNPs rs2043556 and rs4909237 in the precursor region of hsa-miR-605 and pre-hsa-miR-499a/pre-hsa-miR-499b. Their gene-gene interaction, which suggests that the polymorphisms of miRNA genes might not contribute to schizophrenia susceptibility in the Han Chinese population. CONCLUSION: No significant difference existed between schizophrenic patients and controls in SNP (rs2043556 and rs4909237) in the precursor region of hsa-miR-605 and pre-hsa-miR-499a/pre-hsa-miR-499b. There may not regulate FGA gene expression. Thus, hsa-miR-605 and pre-hsa-miR-499a/pre-hsa-miR-499b may not influence the risks of schizophrenia.

7.
Dis Markers ; 2019: 8062397, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31061683

RESUMEN

Recent research has shown that prenatal famine exposure may be one of the risk factors for schizophrenia and that people born in famine years may be at an increased risk of schizophrenia due to alteration of the DNA methylation of genes. In this study, the association of rs2283291/rs4648635 and the incidence of schizophrenia and prenatal famine exposure at the genetic level were investigated to provide clues to the pathogenesis of schizophrenia. A total of 960 participants were recruited, comprising 473 prenatal famine-exposed individuals (225 patients and 248 controls) and 487 prenatal non-famine-exposed individuals (220 patients and 267 controls). The association of prenatal famine, schizophrenia, and their interaction with DNA methylation levels was analyzed using SPSS and GMDR software. Gender stratification analysis revealed a significant association between the rs2283291 genotype and schizophrenia in male patients (P = 0.017), and difference still existed after correction by the Bonferroni method. It was also found that an increasing risk of schizophrenia was associated with rs2283291 in males (OR: 1.62, 95% CI: 1.13-2.33, P = 0.0086, AIC = 669.7) in an overdominant model. The results of gene-environment interaction and gene-gene interaction revealed no association with the risk of schizophrenia. This study reported for the first time that rs2283291 was associated with schizophrenia in Chinese males.


Asunto(s)
Canales de Calcio Tipo L/genética , Desnutrición/epidemiología , Polimorfismo de Nucleótido Simple , Esquizofrenia/genética , China , Femenino , Interacción Gen-Ambiente , Humanos , Masculino , Persona de Mediana Edad , Esquizofrenia/epidemiología , Factores Sexuales
8.
J Affect Disord ; 245: 950-956, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30699880

RESUMEN

BACKGROUND: Although psychological distress is common among patients with chronic diseases, the degree of risk for developing psychological distress is not well-established. Our aim with this study is to determine the odds ratio for psychological distress in patients with cancer as compared to either 1) patients with chronic disease patients without cancer, or 2) healthy controls in a large representative sample of Chinese population. METHODS: Using a multistage, stratified cluster sampling method, 21,101 subjects 18-79 years old were interviewed face-to-face in Jilin province, China. Their psychological status was assessed with the 12-item General Health Questionnaire (GHQ-12). A total score of ≥4 was used as the threshold for determining psychological distress. RESULTS: The prevalence of psychological distress was 14.08% across the entire sample: 10.63% in healthy controls; 14.81% in patients with chronic diseases; and 20% in patients with cancer. Multiple logistic regression analysis indicated that, as compared to the health controls, both cancer (OR = 1.609, 95%CI = 1.245-2.081) and chronic disease patients (OR = 1.330, 95%CI = 1.189-1.478) were more likely to suffer from psychological distress. Moreover, cancer patients had a higher risk of psychological distress than patients with chronic diseases (OR = 1.295, 95%CI = 1.049-1.600; p = 0.016). In addition, the cancer group (2.68 ±â€¯0.114) demonstrated a higher GHQ score than the patients with chronic diseases (2.30 ±â€¯0.017) and healthy controls (1.98 ±â€¯0.029) (both p < 0.001). CONCLUSION: Our results showed both a higher rate and greater degree of psychological distress in patients with cancer. This suggests a need for better psychological management in cancer patients to help alleviate their distress.


Asunto(s)
Ansiedad/epidemiología , Depresión/epidemiología , Neoplasias/epidemiología , Estrés Psicológico/epidemiología , Adolescente , Adulto , Anciano , Ansiedad/psicología , China/epidemiología , Enfermedad Crónica , Estudios Transversales , Depresión/psicología , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Neoplasias/psicología , Oportunidad Relativa , Prevalencia , Estrés Psicológico/psicología , Adulto Joven
9.
Cell Physiol Biochem ; 46(6): 2480-2486, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29742493

RESUMEN

BACKGROUND/AIMS: Schizophrenia is a severe psychiatric disorder, and complement 3 (C3) is closely related to schizophrenia. We investigated the association between C3 polymorphisms and schizophrenia in a Northeast Han Chinese population. METHODS: A total of 2240 Chinese people, consisting of 1086 patients with schizophrenia and 1154 healthy controls, were recruited for this study. Ten single nucleotide polymorphisms (SNPs; rs11569562, rs344555, rs2241393, rs2241392, rs11569514, rs445750, rs451760, rs11672613, rs2230205, and rs2250656) in C3 were selected and genotyped. RESULTS: Genotype distribution analysis indicated that rs11569514 was significantly associated with schizophrenia. In the dominant model (AA vs. GG+GA genotypes), we found a significant protective effect for rs344555 against schizophrenia (odds ratio [OR]: 0.72, 95% confidence interval [CI]: 0.53-0.99, P = 0.04). In the codominant model (TT vs. AA), we found a significant risk effect for rs11569514 on schizophrenia (OR: 4.39, 95% CI: 2.06-9.37, P < 0.001). Haplotypes, including TG (rs11569562 and rs344555), TGG (rs11569562-rs344555-rs2241393), AG (rs344555-rs2241393), CGGGT (rs11569562-rs344555-rs2241393-rs2241392-rs11569514), and ACGTG (rs11569514-rs445750-rs451760-rs11672613-rs2230205), showed either a risk or protective role for schizophrenia. CONCLUSIONS: SNP rs11569514 in C3 and haplotypes of C3 variants were associated with schizophrenia in a Han Chinese population.


Asunto(s)
Complemento C3/genética , Polimorfismo de Nucleótido Simple , Esquizofrenia/genética , Adulto , Pueblo Asiatico/genética , Estudios de Casos y Controles , China/epidemiología , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Esquizofrenia/epidemiología
10.
Angew Chem Int Ed Engl ; 51(34): 8573-6, 2012 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-22807193

RESUMEN

Building the building blocks: A highly enantioselective hydrogenation of ß-aryl-ß-alkyl disubstituted nitroalkenes 1 has been developed. This method results in enantiomerically pure nitroalkanes 2, which are versatile precursors for chemical synthesis.


Asunto(s)
Alquenos/química , Nitroparafinas/síntesis química , Catálisis , Hidrogenación , Nitroparafinas/química , Estereoisomerismo
11.
Chemistry ; 18(32): 9992-8, 2012 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-22782739

RESUMEN

New tetraphosphorus ligands have been developed and applied in the rhodium-catalyzed regioselective hydroformylation of a variety of functionalized allyl and vinyl derivatives. Remarkably high linear selectivity was obtained by these tetraphosphorus ligands. The ligand that bears strong electron-withdrawing 2,4-difluorophenyl groups is the most effective one in affording linear aldehydes. The Rh/tetraphosphorus ligand catalyst is highly effective to produce linear aldehydes from functionalized allyl derivatives with heteroatoms or aromatic groups directly adjacent to the allyl group. For vinyl derivatives, the ligand is highly linear selective for acrylic derivatives, styrene, vinyl pyridine, and vinyl phthalimide. Linear to branch ratios of 26:1 and 10:1 were obtained for the hydroformylation of styrene and allyl cyanide, respectively.


Asunto(s)
Alquenos/química , Compuestos Organofosforados/química , Rodio/química , Compuestos de Vinilo/química , Catálisis , Ligandos , Estructura Molecular , Estereoisomerismo
12.
Org Lett ; 14(1): 102-5, 2012 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-22149490

RESUMEN

A highly regioselective isomerization-hydroaminomethylation of internal olefins has been developed. A 95.3% amine selectivity and 36.2 n/i ratio were obtained for 2-octene with a Tetrabi ligand and Rh(acac)(CO)(2), and a TON of linear amine was achieved of 6837 with a 39.1 n/i ratio of amine. The m-CF(3)-Ph substituted ligand was the best of the applied Tetrabi-type phosphorus ligands for different internal olefins, as up to a 99.2% amine selectivity and 95.6 n/i ratio were obtained for 2-pentene.


Asunto(s)
Alquenos/química , Hidrógeno/química , Fósforo/química , Rodio/química , Aminación , Catálisis , Ligandos , Metilación , Estructura Molecular , Estereoisomerismo
13.
Chemistry ; 17(51): 14559-63, 2011 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-22105788

RESUMEN

A highly regioselective hydroaminomethylation of terminal olefins catalyzed by Rh complexes with 2, 2', 6, 6'-tetrakis ((diphenylphosphino)methyl)-1, 1'-biphenyl (Tetrabi) ligand has been developed. Up to 99 % amine selectivity, 168 linear/branched amine product ratio (n/i), and 97.4 % linear amine yield has been obtained at a substrate/rhodium precursor ratio (S/Rh) of 1000 with this methodology. The turnover number was achieved 6930 at 10,000 S/Rh ratio, and the n/i can reach up to >525. Several different olefins and secondary amines have been applied successfully with high chemoselectivity (99 %), yield (>98 %), and regioselectivity (>120).


Asunto(s)
Alquenos/química , Aminas/síntesis química , Compuestos de Bifenilo/química , Compuestos Organometálicos/química , Compuestos Organofosforados/química , Rodio/química , Aminas/química , Catálisis , Ligandos , Estructura Molecular , Estereoisomerismo
14.
Chem Commun (Camb) ; 46(45): 8555-7, 2010 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-20944852

RESUMEN

A novel three hindered quadrant bisphosphine ligand has been synthesized. The ligand shows excellent enantioselectivities and reactivities for rhodium-catalyzed hydrogenations of various functionalized olefins.


Asunto(s)
Diseño de Fármacos , Fosfinas/química , Fosfinas/síntesis química , Catálisis , Ácidos Ciclohexanocarboxílicos/química , Ácidos Dicarboxílicos/química , Hidrogenación , Ligandos , Rodio/química , Estereoisomerismo , Especificidad por Sustrato
17.
Chemistry ; 16(3): 871-7, 2010 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-19950337

RESUMEN

A series of hybrid phosphine-phosphoramidite ligands has been designed and synthesized in moderate yields from chiral BINOL (1,1'-bi-2-naphthol) or NOBIN (2-amino-2'-hydroxy-1,1'-binaphthyl). They have achieved highly regio- and enantioselectivities in Rh-catalyzed asymmetric hydroformylations of styrene derivatives (branched/linear ratio up to 56.6, ee up to 99 %), vinyl acetate derivatives (up to 98 % ee), and allyl cyanide (up to 96 % ee). Systematic variation of ligand structure showed that the steric factor on the phsophoramidite moiety determined the performance of the ligand. With the increased hindrance, the branched/linear ratio rose, while the ee value dropped in the hydroformylation of styrene. However, the N-substituents did not influence the selectivities much.


Asunto(s)
Ligandos , Compuestos Organofosforados/síntesis química , Fosfinas/química , Catálisis , Naftalenos/química , Naftoles/química , Nitrilos/química , Compuestos Organofosforados/química , Rodio , Estereoisomerismo , Relación Estructura-Actividad , Estireno/química , Compuestos de Vinilo/química
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