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1.
Nature ; 629(8012): 555-560, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38658758

RESUMO

The tokamak approach, utilizing a toroidal magnetic field configuration to confine a hot plasma, is one of the most promising designs for developing reactors that can exploit nuclear fusion to generate electrical energy1,2. To reach the goal of an economical reactor, most tokamak reactor designs3-10 simultaneously require reaching a plasma line-averaged density above an empirical limit-the so-called Greenwald density11-and attaining an energy confinement quality better than the standard high-confinement mode12,13. However, such an operating regime has never been verified in experiments. In addition, a long-standing challenge in the high-confinement mode has been the compatibility between a high-performance core and avoiding large, transient edge perturbations that can cause very high heat loads on the plasma-facing-components in tokamaks. Here we report the demonstration of stable tokamak plasmas with a line-averaged density approximately 20% above the Greenwald density and an energy confinement quality of approximately 50% better than the standard high-confinement mode, which was realized by taking advantage of the enhanced suppression of turbulent transport granted by high density-gradients in the high-poloidal-beta scenario14,15. Furthermore, our experimental results show an integration of very low edge transient perturbations with the high normalized density and confinement core. The operating regime we report supports some critical requirements in many fusion reactor designs all over the world and opens a potential avenue to an operating point for producing economically attractive fusion energy.

3.
J Chem Phys ; 160(24)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38912677

RESUMO

We present the ab initio thermoelastic properties of body-centered cubic molybdenum under extreme conditions obtained within the quasi-harmonic approximation including both the vibrational and electronic thermal excitation contributions to the free energy. The quasi-harmonic temperature-dependent elastic constants are calculated and compared with existing experiments and with the quasi-static approximation. We find that the quasi-harmonic approximation allows for a much better interpretation of the experimental data, confirming the trend found previously in other metals. Using the Voigt-Reuss-Hill average, we predict the compressional and shear sound velocities of polycrystalline molybdenum as a function of pressure for several temperatures, which might be accessible in experiments.

4.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(6): 891-897, 2024 Jun 06.
Artigo em Zh | MEDLINE | ID: mdl-38955738

RESUMO

To study the carriage status of drug susceptibility, clonal complex groups, serotypes, surface proteins and virulence genes of Streptococcus agalactiae from respiratory specimen sources. A total of 35 strains of S.agalactiae meeting the criteria were collected from 3 hospitals in 2 locations, Tangshan and Jinan. The age span of the patients was 3 days-92 years, and the percentage of elderly patients≥60 years was 71.5%.The susceptibility to 9 antimicrobial drugs was measured and analyzed using the micro broth dilution method. The strains were 100.0% sensitive to penicillin, linezolid, vancomycin, and ceftriaxone; However, it exhibits high resistance rates to erythromycin, clindamycin and levofloxacin, at 97.1%, 85.7% and 82.9% respectively; and the resistance rates to tetracycline and chloramphenicol were 34.3% and 14.2%, respectively. Genome sequence determination and analysis showed that 16 resistance genes were detected in 35 strains, among which: macrolide and lincosamide resistance genes were mainly ermB, with a carrying rate of 74.2%; tetracycline resistance genes were mainly tetM, with a carrying rate of 25.7%; in addition, the mutation rates of the quinolone resistance determinants gyrA and parC were 88.5% and 85.7%, respectively. 35 strains belonged to 6 ST types and 4 clonal groups, with CC10/ST10 as the main one, accounting for 62.8%; they contained 4 serotypes of Ⅰb, Ⅱ, Ⅲ, and Ⅴ, as well as 1 untyped strain, with serotype Ⅰb as the main one, accounting for 65.7%. The strains carried three pilus types, PI1+PI2a, PI2a and PI2b types, respectively, and detected five surface proteins, alpha, alp1, rib, srr, and rdf_0594, and seven virulence factors, cba, cfb, cylE, fbsA, hylB, lmb, and pavA. Overall, S.agalactiae isolated from respiratory tract specimens is predominantly sourced from elderly patients, with CC10 strains being most prevalent. These strains harbor multiple drug-resistant and virulence genes, demonstrating elevated resistance rates to macrolides, lincosamides, and quinolones. This emphasizes the necessity for vigilant attention to the health threat posed by S. agalactiae from respiratory tract speciments of elderly patients.


Assuntos
Antibacterianos , Testes de Sensibilidade Microbiana , Streptococcus agalactiae , Streptococcus agalactiae/genética , Streptococcus agalactiae/efeitos dos fármacos , Humanos , Idoso , Antibacterianos/farmacologia , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Adulto , Criança , Adolescente , Pré-Escolar , Lactente , Adulto Jovem , Recém-Nascido , Farmacorresistência Bacteriana/genética , Infecções Estreptocócicas/microbiologia
5.
Phys Rev Lett ; 130(7): 076101, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36867795

RESUMO

Silicon (Si) exhibits a rich collection of phase transitions under ambient-temperature isothermal and shock compression. This report describes in situ diffraction measurements of ramp-compressed Si between 40 and 389 GPa. Angle-dispersive x-ray scattering reveals that Si assumes an hexagonal close-packed (hcp) structure between 40 and 93 GPa and, at higher pressure, a face-centered cubic structure that persists to at least 389 GPa, the highest pressure for which the crystal structure of Si has been investigated. The range of hcp stability extends to higher pressures and temperatures than predicted by theory.

6.
Phys Rev Lett ; 131(14): 145101, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37862644

RESUMO

We report the observation of a set of coherent high frequency electromagnetic fluctuations that leads to a turbulence induced self-regulating phenomenon in the DIII-D high bootstrap current fraction plasma. The fluctuations have frequency of 130-220 kHz, the poloidal wavelength and phase velocity are 16-30 m^{-1} and ∼30 km/s, respectively, in the outboard midplane with the estimated toroidal mode number n∼5-9. The fluctuations are located in the internal transport barrier (ITB) region at large radius and are experimentally validated to be kinetic ballooning modes (KBM). Quasilinear estimation predicts the KBM to be able to drive experimental particle flux and non-negligible thermal flux, suggesting its significant role in regulating the ITB saturation.

7.
Public Health ; 221: 106-115, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37441994

RESUMO

OBJECTIVES: This systematic review was conducted to estimate the respective prevalence of gonorrhea among two high-risk populations in China and determine the epidemiological features of gonorrhea in them. STUDY DESIGN: Systematic review. METHODS: PubMed, Web of Science, China National Knowledge Infrastructure, and Wanfang databases were searched to identify studies published between January 1, 1990, and October 31, 2022, with gonorrhea prevalence tested by polymerase chain reaction among female sex workers (FSWs) and men who have sex with men (MSM). Meta-regression and subgroup analyses were used to investigate potential factors of heterogeneity across studies. Trend analysis of prevalence was conducted by the Jonckheere-Terpstra method. RESULTS: We identified 88 prevalence data points from 49 studies in China, with 30,853 participants of FSWs and 5523 participants of MSM. Pooled prevalence of gonorrhea among FSWs and MSM were 6.9% (95% confidence interval: 4.6-9.7%) and 2.5% (95% confidence interval: 1.5-3.7%), respectively. The subgroup analyses showed there were period, regional, and specimen collection methods diversities among FSWs, and diversities of the regions and specimen collection anatomical sites were found among MSM, in which the prevalence of rectum and pharynx was significantly higher than the urethra. A decreasing trend in the prevalence of gonorrhea was seen among FSWs (z = -4.03) from 1999 to 2021, not found for MSM in China. CONCLUSION: The prevalence of gonorrhea is high in two high-risk groups in China, with extragenital infections requiring particular attention. The findings of this study will provide evidence to formulate national policy and guidance for gonorrhea prevention and control.


Assuntos
Infecções por Chlamydia , Gonorreia , Infecções por HIV , Profissionais do Sexo , Minorias Sexuais e de Gênero , Masculino , Humanos , Feminino , Gonorreia/epidemiologia , Homossexualidade Masculina , Infecções por Chlamydia/epidemiologia , Prevalência , China/epidemiologia , Infecções por HIV/epidemiologia
8.
Zhonghua Fu Chan Ke Za Zhi ; 58(10): 774-782, 2023 Oct 25.
Artigo em Zh | MEDLINE | ID: mdl-37849258

RESUMO

Objective: To characterize the relationship between the levels of plasma methyl donor and related metabolites (including choline, betaine, methionine, dimethylglycine and homocysteine) and fetal growth in twin pregnancies. Methods: A hospital-based cohort study was used to collect clinical data of 92 pregnant women with twin pregnancies and their fetuses who were admitted to Peking University Third Hospital from March 2017 to January 2018. Fasting blood was collected from the pregnant women with twin pregnancies (median gestational age: 18.9 weeks). The levels of methyl donors and related metabolites in plasma were quantitatively analyzed by high-performance liquid chromatography combined with mass spectrometry. The generalized estimation equation was used to analyze the relationship between maternal plasma methyl donors and related metabolites levels and neonatal outcomes of twins, and the generalized additive mixed model was used to analyze the relationship between maternal plasma methyl donors and related metabolites levels and fetal growth ultrasound indicators. Results: (1) General clinical data: of the 92 women with twin pregnancies, 66 cases (72%) were dichorionic diamniotic (DCDA) twin pregnancies, and 26 cases (28%) were monochorionic diamniotic (MCDA) twin pregnancies. The comparison of the levels of five plasma methyl donors and related metabolites in twin pregnancies with different basic characteristics showed that the median levels of plasma choline and betaine in pregnant women ≥35 years old were higher than those in pregnant women <35 years old, and the differences were statistically significant (all P<0.05). (2) Correlation between plasma methyl donor and related metabolites levels and neonatal growth indicators: after adjusting for confounding factors, plasma homocysteine level in pregnant women with twins was significantly negatively correlated with neonatal birth weight (ß=-47.9, 95%CI:-94.3- -1.6; P=0.043). Elevated methionine level was significantly associated with decreased risks of small for gestational age infants (SGA; OR=0.5, 95%CI: 0.3-0.9; P=0.021) and low birth weight infants (OR=0.6, 95%CI: 0.4-0.9; P=0.020). Increased homocysteine level was associated with increased risks of SGA (OR=1.5, 95%CI: 1.0-2.2; P=0.029) and inconsistent growth in twin fetuses (OR=1.9, 95%CI: 1.0-3.7; P=0.049). (3) Correlation between the levels of plasma methyl donors and related metabolites and intrauterine growth indicators of twins pregnancies: for every 1 standard deviation increase in plasma choline level in pregnant women with twin pregnancies, fetal head circumference, abdominal circumference, femoral length and estimated fetal weight in the second trimester increased by 1.9 mm, 2.6 mm, 0.5 mm and 20.1 g, respectively, and biparietal diameter, abdominal circumference and estimated fetal weight increased by 0.7 mm, 3.0 mm and 38.4 g in the third trimester, respectively, and the differences were statistically significant (all P<0.05). (4) Relationship between plasma methyl donor and related metabolites levels in pregnant women with different chorionicity and neonatal birth weight and length: the negative correlation between plasma homocysteine level and neonatal birth weight was mainly found in DCDA twin pregnancy (ß=-65.9, 95%CI:-110.6- -21.1; P=0.004). The levels of choline, betaine and dimethylglycine in plasma of MCDA twin pregnancy were significantly correlated with the birth weight and length of newborns (all P<0.05). Conclusion: Homocysteine level is associated with low birth weight in twins, methionine is associated with decreased risk of SGA, and choline is associated with fetal growth in the second and third trimesters of pregnancy.


Assuntos
Peso ao Nascer , Desenvolvimento Fetal , Gravidez de Gêmeos , Adulto , Feminino , Humanos , Recém-Nascido , Gravidez/sangue , Gravidez/metabolismo , Betaína/sangue , Betaína/metabolismo , Peso ao Nascer/fisiologia , Colina/sangue , Colina/metabolismo , Estudos de Coortes , Desenvolvimento Fetal/fisiologia , Peso Fetal/fisiologia , Homocisteína/sangue , Homocisteína/metabolismo , Metionina/sangue , Metionina/metabolismo , Gravidez de Gêmeos/sangue , Gravidez de Gêmeos/fisiologia , Biomarcadores/sangue , Biomarcadores/metabolismo , Trimestres da Gravidez/sangue , Trimestres da Gravidez/fisiologia , Resultado da Gravidez
9.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(10): 1640-1646, 2023 Oct 06.
Artigo em Zh | MEDLINE | ID: mdl-37859384

RESUMO

Objective: To explore the influencing factors of electronic cigarette use among adolescent students in China. Methods: We searched CNKI, Database of Chinese sci-tech periodicals (VIP), Wan-fang database, PubMed, Web of Science and ScienceDirect for potentially relevant articles published from the inception to March 20th, 2023. The Metagen package in R was used for Meta-analysis. Results: A total of 19 publications with a sample size of 5 336 017 were identified. The results showed that electronic cigarette use among Chinese adolescent students was associated with gender (OR=2.41, 95%CI: 2.03-2.86), close friends smoking (OR=3.02, 95%CI: 2.08-4.39), current smoking (OR=11.26, 95%CI: 4.35-29.18), friends using electronic cigarettes (OR=5.19, 95%CI: 2.01-13.38), thinking smoking makes young people look more attractive (OR=2.00, 95%CI: 1.35-2.97), type of school (OR=2.10, 95%CI: 1.59-2.78), thinking smoking makes people feel more comfortable in social situations (OR=3.58, 95%CI: 2.99-4.28), other tobacco use (OR=5.53, 95%CI: 3.33-9.20), and ever experimented with cigarette use (OR=9.32, 95%CI: 4.38-19.80). Conclusion: The influencing factors for electronic cigarette use among adolescent students in China include gender, close friends smoking, current smoking, friends using electronic cigarettes, thinking smoking makes young people look more attractive, type of school, thinking smoking makes people feel more comfortable in social situations, other tobacco use, and ever experimented with cigarette use.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Vaping , Adolescente , Humanos , Estudos Transversais , População do Leste Asiático , Estudantes
10.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57: 65-71, 2023 Jul 03.
Artigo em Zh | MEDLINE | ID: mdl-37400221

RESUMO

Objective: To analyze the drug resistance and multilocus sequence typing of five types of diarrheagenic Escherichia coli (DEC) isolated from diarrhea outpatients of diarrhea comprehensive monitoring designated hospital in Qingpu District, Shanghai from 2015 to 2019. Methods: From January 2015 to December 2019, five types of DEC, isolated and identified from diarrhea outpatient cases' anal swabs of the Qingpu branch of Zhongshan Hospital were collected to determine the minimal inhibitory concentration by using the micro broth dilution susceptibility test. The strains, resistant to the third-generation cephalosporins or carbapenems, or producing ESBLs, were selected based on the results of sensitivity tests and determined by WGS. The MLST typing of DEC was analyzed based on the WGS technology and the minimum spanning tree was constructed by BioNumerics 7.6 software to analyze the local dominant flora. Results: A total of 513 strains of DEC were detected and isolated from 4 494 anal swabs, with a detection rate of 11.42%. About 500 strains were tested for drug sensitivity to nine antibiotics in four classes, including 330 strains of enterotoxigenic E.coli (ETEC), 72 strains of enteroaggregative E.coli (EAEC), 95 strains of enteropathogenic E.coli (EPEC), 1 strain of enterohemorrhagic E.coli (EHEC), and 2 strains of enteroinvasive E.coli (EIEC). From 2015 to 2019, the resistance rate of cefotaxime-clavulanic acid was significantly different (P<0.05). The resistance rate of virulence types of DEC to nalixic acid was significantly different (P<0.05). About 71 strains of DEC were determined by WGS, and 77 drug-resistant genes were detected. Strains were classified into 32 ST subtypes, with the dominant genotypes being ST-1491 (29.6%, 21/71) and ST-10 Complex (23.9%, 17/71). All ST-1491 produced ESBLs, which were blaCTX-M gene mutant strains. The dominant type of ST-10 complex was ST-218 (35.3%, 6/17). In addition, 8 strains of EAEC, 14 strains of EPEC and 49 strains of ETEC were classified into 7, 14 and 18 ST subtypes, respectively. Conclusion: The drug resistance of DEC strains from the diarrhea outpatient case of Qingpu District is serious. The ST types of EAEC and EPEC are highly polymorphic. The dominant ST types of DEC are basically consistent with the common genotypes in southeast China.

11.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(8): 1199-1205, 2023 Aug 06.
Artigo em Zh | MEDLINE | ID: mdl-37574313

RESUMO

Objective: To analyze the drug resistance and multilocus sequence typing of five types of diarrheagenic Escherichia coli (DEC) isolated from diarrhea outpatients of diarrhea comprehensive monitoring designated hospital in Qingpu District, Shanghai City from 2015 to 2019. Methods: From January 2015 to December 2019, five types of DEC, isolated and identified from diarrhea outpatient cases' anal swabs of the Qingpu branch of Zhongshan Hospital were collected to determine the minimal inhibitory concentration by using the micro broth dilution susceptibility test. The strains, resistant to the third-generation cephalosporins or carbapenems, or producing ESBLs, were selected based on the results of sensitivity tests and determined by WGS. The MLST typing of DEC was analyzed based on the WGS technology and the minimum spanning tree was constructed by BioNumerics 7.6 software to analyze the local dominant flora. Results: A total of 513 strains of DEC were detected and isolated from 4 494 anal swabs, with a detection rate of 11.42%. About 500 strains were tested for drug sensitivity to nine antibiotics in four classes, including 330 strains of enterotoxigenic E.coli (ETEC), 72 strains of enteroaggregative E.coli (EAEC), 95 strains of enteropathogenic E.coli (EPEC), 1 strain of enterohemorrhagic E.coli (EHEC), and 2 strains of enteroinvasive E.coli (EIEC). From 2015 to 2019, the resistance rate of cefotaxime-clavulanic acid was significantly different (P<0.05). The resistance rate of virulence types of DEC to nalixic acid was significantly different (P<0.05). About 71 strains of DEC were determined by WGS, and 77 drug-resistant genes were detected. Strains were classified into 32 ST subtypes, with the dominant genotypes being ST-1491 (29.6%, 21/71) and ST-10 Complex (23.9%, 17/71). All ST-1491 produced ESBLs, which were blaCTX-M gene mutant strains. The dominant type of ST-10 complex was ST-218 (35.3%, 6/17). In addition, 8 strains of EAEC, 14 strains of EPEC and 49 strains of ETEC were classified into 7, 14 and 18 ST subtypes, respectively. Conclusion: The drug resistance of DEC strains from the diarrhea outpatient case of Qingpu District is serious. The ST types of EAEC and EPEC are highly polymorphic. The dominant ST types of DEC are basically consistent with the common genotypes in southeast China.

12.
Niger J Clin Pract ; 26(9): 1234-1241, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37794534

RESUMO

Background: Cervical spondylopathy is a common musculo-articular disorder, multiple exercises are recommended. Chinese fitness exercises are prevalent and used to treat various diseases. Aim: To explore the efficacy of Chinese fitness exercise Yi Jin Jing exercise in intervening the cervical spondylopathy in adolescents. Patients and Methods: The study was conducted in 60 adolescent patients with cervical spondylopathy, with 30 patients in each group. Methods: The study was conducted in 60 adolescent patients with cervical spondylopathy, with 30 patients in each group. The observation group was required to take Yi Jin Jing exercise, and the control group took the brisk walking exercise. The first week was the preparatory period for the patients, and then the participants were required to do exercises three times a week for at least 30 minutes in the later 3 weeks. Before and after treatment, Neck Disability Index (NDI) scores, pain visual analog scale (VAS) scores, and cervical curvature in both groups were observed, and the incidence of adverse events in both groups was recorded during the trial. Results: The NDI and VAS scores in both groups statistically decreased after intervention and mildly increased at follow-up, while the reduction in scores of the Yi Jin Jing group was more significant. Cervical curvature in both groups improved on day 28 compared to day 0. There were no adverse reactions during the evaluation period. Conclusion: The Chinese health-care qigong Yi Jin Jing exercise is more effective than brisk walking in improving the cervical range of motion and relieving pain in adolescents with cervical spondylopathy. Trial registration/Protocol registration: Clinical Trial Registry (ChiCTR2000030723).


Assuntos
Exercício Físico , Pescoço , Humanos , Adolescente , China , Terapia por Exercício , Dor , Resultado do Tratamento , Vértebras Cervicais
13.
Phys Rev Lett ; 128(8): 085003, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35275672

RESUMO

High-ß_{θe} (a ratio of the electron thermal pressure to the poloidal magnetic pressure) steady-state long-pulse plasmas with steep central electron temperature gradient are achieved in the Experimental Advanced Superconducting Tokamak. An intrinsic current is observed to be modulated by turbulence driven by the electron temperature gradient. This turbulent current is generated in the countercurrent direction and can reach a maximum ratio of 25% of the bootstrap current. Gyrokinetic simulations and experimental observations indicate that the turbulence is the electron temperature gradient mode (ETG). The dominant mechanism for the turbulent current generation is due to the divergence of ETG-driven residual flux of current. Good agreement has been found between experiments and theory for the critical value of the electron temperature gradient triggering ETG and for the level of the turbulent current. The maximum values of turbulent current and electron temperature gradient lead to the destabilization of an m/n=1/1 kink mode, which by counteraction reduces the turbulence level (m and n are the poloidal and toroidal mode number, respectively). These observations suggest that the self-regulation system including turbulence, turbulent current, and kink mode is a contributing mechanism for sustaining the steady-state long-pulse high-ß_{θe} regime.

14.
Ultrasound Obstet Gynecol ; 60(4): 506-513, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35468234

RESUMO

OBJECTIVES: To summarize our experience in the application of radiofrequency ablation (RFA) and microwave ablation (MWA) for selective fetal reduction in complicated monochorionic pregnancies and compare the perinatal outcome of the two techniques. METHODS: This was a retrospective study of data from a consecutive cohort of all monochorionic twin pregnancies that underwent selective fetal reduction with RFA or MWA at Peking University Third Hospital, Beijing, China from January 2012 to December 2018. All surviving cotwins were followed up to assess their neurodevelopment using the Age & Stage Questionnaire, Chinese version. Perinatal and neurodevelopmental outcomes were compared between the RFA and MWA groups. We also fitted multivariable models to test the association between procedure-related factors and the main perinatal outcomes, including preterm birth (PTB) < 37 weeks' gestation, intrauterine fetal death (IUFD) of the cotwin, adverse outcome (defined as occurrence of IUFD of the cotwin, termination of pregnancy or PTB < 28 weeks) and overall survival. RESULTS: In total, 45 cases (42 twin and three triplet pregnancies) underwent RFA and 126 cases (105 twin and 21 triplet pregnancies) underwent MWA. The overall survival rates in monochorionic diamniotic twin pregnancies were similar between the RFA and MWA groups (61.0% vs 67.0%; P = 0.494). However, pregnancies whose indication for fetal reduction was selective intrauterine growth restriction or twin reversed arterial perfusion had higher overall survival rates (75.5% and 82.6%, respectively) compared with those in other indication groups. A total of 104 children were followed up (20 in the RFA group and 84 in the MWA group); four (20.0%) and eight (9.5%) children were assessed as having overall developmental delay in the RFA and MWA groups, respectively, with no significant difference between the two groups. Multivariable analyses showed that procedure indication, number of ablation cycles and gestational age at procedure were associated significantly with the main perinatal outcomes. CONCLUSIONS: RFA and MWA for selective fetal reduction in complicated monochorionic pregnancies can achieve similar overall survival rate and neurodevelopmental outcome, but MWA is associated with a lower risk of preterm birth. Moreover, procedure-related factors are associated significantly with perinatal outcome. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Complicações na Gravidez , Nascimento Prematuro , Ablação por Radiofrequência , Criança , Feminino , Morte Fetal/etiologia , Retardo do Crescimento Fetal , Idade Gestacional , Humanos , Recém-Nascido , Micro-Ondas/uso terapêutico , Gravidez , Complicações na Gravidez/etiologia , Resultado da Gravidez/epidemiologia , Redução de Gravidez Multifetal/métodos , Gravidez de Gêmeos , Nascimento Prematuro/etiologia , Nascimento Prematuro/prevenção & controle , Ablação por Radiofrequência/métodos , Estudos Retrospectivos
15.
Clin Radiol ; 77(4): 299-306, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35094817

RESUMO

AIM: To assess the relationship between gadolinium deposition in the brain and various gadolinium-based contrast agents (GBCAs) and to explore confounding variables. METHODS: The study group included 87 patients with multiple enhanced brain magnetic resonance imaging (MRI) examinations of which 48 patients were in the linear GBCA group (33 patients in gadopentetate dimeglumine group and 15 patients in gadobenate dimeglumine group) and 39 patients in the macrocyclic GBCA group (22 patients in gadobutrol group and 17 patients in gadoterate meglumine group). The control group included 87 normal participants who were matched regarding age, sex, MRI machine and imaging sequences to the study cohort. T1 signal intensity (SI) ratios of the dentate nucleus to the pons (DN/pons) and of the globus pallidus to the frontal white matter (GP/FWM) in both groups were calculated and compared. The relationships between SI ratios and confounding variables were analysed. RESULTS: Significant differences were detected between two linear GBCA groups and control groups in T1 SI ratios of the DN/pons and GP/FWM (all p<0.001). There were no differences for two the macrocyclic GBCA groups compared with matching control groups (all p>0.05). T1 SI ratios of the linear GBCA group were significantly higher than those of the macrocyclic GBCA group (p<0.001). In the linear GBCA group, the T1 SI ratios of the DN/pons correlated moderately positively with the number of GBCA administrations (r=0.643, p<0.001), and MRI machine and sequence used. CONCLUSIONS: Increased T1 SI could be observed after repeated administrations of linear GBCA. T1 SI of the DN correlated with the number of linear GBCA administrations, and detection might be affected by MRI machine and sequence.


Assuntos
Meios de Contraste , Gadolínio , Encéfalo/diagnóstico por imagem , Estudos de Casos e Controles , Humanos , Estudos Retrospectivos
16.
Zhonghua Yan Ke Za Zhi ; 58(11): 914-916, 2022 Nov 11.
Artigo em Zh | MEDLINE | ID: mdl-36348528

RESUMO

A patient complained of progressive visual acuity decline in the left eye for 3 years was admitted. The appearance of the patient was bilateral microcornea. After ocular ultrasonography, ultrasound biomicroscopy, etc, the patient was diagnosed as sclerocornea of the left eye with open-angle glaucoma. Trabeculectomy of the left eye was performed after drug treatment failed, and there were no surgical complications. The intraocular pressure of the left eye was normal and the anterior chamber was well formed 6 months after surgery.


Assuntos
Doenças da Córnea , Glaucoma de Ângulo Aberto , Trabeculectomia , Humanos , Glaucoma de Ângulo Aberto/complicações , Glaucoma de Ângulo Aberto/cirurgia , Pressão Intraocular , Doenças da Córnea/cirurgia
17.
Osteoporos Int ; 32(9): 1785-1793, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33655399

RESUMO

China is a middle-risk country for hip fracture at present, which differs from previous data that it was low-risk. By 2050, the total number of hip fractures in people older than 65 years is predicted to be 1.3 million. INTRODUCTION: To assess hip fracture incidence in China and examine the heterogeneity of hip fracture in seven geographical regions of China. METHODS: There were 238,230 hip fracture patients aged 65 years or older from 2013 to 2016 from a large national in-patients database (HQMS) involving 30.6 million hospitalizations. Taking into account the total national hospitalization rate per calendar year, we estimated the incidence of hip fracture per 100,000 residents older than 65 years in China overall and in seven geographical Chinese regions. RESULTS: The proportion of men and women older than 65 years with hip fractures was 1.00:1.95. Between 2013 and 2016, the number of hip fractures per 100,000 people age 65+ was 278. China has vast territories; the number of hip fractures per 100,000 people over 65 years old was 202 in Northeast China and 374 in Northwest China. Northwest has higher altitude, lower population density, is less developed with lower urbanization than Northeast China which is low altitude, and highly urbanized. CONCLUSIONS: China should no longer be regarded as a low-risk country for hip fracture. By 2050, the total number of hip fractures in people older than 65 years in China is predicted to be 1.3 million. Higher altitude areas had higher hip fracture rates than lower altitude, higher urbanized areas.


Assuntos
Fraturas do Quadril , Ossos Pélvicos , Idoso , China/epidemiologia , Feminino , Fraturas do Quadril/epidemiologia , Hospitalização , Humanos , Incidência , Masculino
18.
J Chem Phys ; 154(11): 114103, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33752342

RESUMO

We have developed a software package, namely, PASP (Property Analysis and Simulation Package for materials), to analyze the structural, electronic, magnetic, and thermodynamic properties of complex condensed matter systems. Our package integrates several functionalities including symmetry analysis, global structure searching methods, effective Hamiltonian methods, and Monte Carlo simulation methods. In conjunction with first-principles calculations, PASP has been successfully applied to diverse physical systems. In this paper, we give a brief introduction to its main features and underlying theoretical formulism. Some typical applications are provided to demonstrate the usefulness, high efficiency, and reliability of PASP. We expect that further developments will make PASP a general-purpose tool for material simulation and property calculation of condensed matters.

19.
Aquaculture ; 530: 735759, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33456090

RESUMO

Aquaculture, the fastest growing food production sector cannot continue to rely on finite stocks of marine fish as the primary source of the omega-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFA), eicosapentaenoic acid (EPA; 20:5n3) and docosahexaenoic acid (DHA; 22:6n-3), for feeds. A four-month feeding trial was conducted to investigate the impact of a de novo oil, with high levels of EPA and DHA, obtained from transgenic Camelina sativa on growth performance, tissue fatty acid profiles, and expression of lipid metabolism genes when used as a replacement for fish oil in feed for European seabass (Dicentrachus labrax). Triplicate groups of 50 juvenile fish (initial weight 16.7 ± 0.92 g) per tank were fed for 4 months with one of three isolipidic and isoproteic experimental diets consisting of a standard diet containing a commercial blend of fish oil and rapeseed oil (CFO), a diet containing transgenic Camelina oil (TCO), or a blend of fish oil and rapeseed oil with enhanced levels of EPA and DHA (EFO) formulated to match the n-3 LC-PUFA profile of the TCO feed. Final weight of fish fed the GM-derived oil was not different to fish fed either CFO or EFO. Slight lower growth performance of fish fed TCO at the beginning of the trial was related to transient reduced feed intake, possibly caused by glucosinolates in the raw Camelina sativa oil. The GM-derived oil improved the nutritional quality of the fish fillet by enhancing total n-3 PUFA levels compared to the fish fed the other two feeds, and maintained flesh EPA and DHA at the same levels as in fish fed the diets containing fish oil. The metabolic response in liver and intestine was generally relatively mild although diets TCO and EFO seemed to trigger a metabolic response consisting of an up-regulation of both ß-oxidation (cpt1a) and fatty acid transport (fabp1), possibly reflecting higher levels of LC-PUFA. Overall, the present study indicated that an oil of terrestrial origin, Camelina sativa, when engineered to contain high levels of EPA and DHA can replace fish oil in feeds for European seabass with no detrimental impact on growth or feed efficiency, while also maintaining or increasing tissue n-3 LC-PUFA contents.

20.
Zhonghua Jie He He Hu Xi Za Zhi ; 44(11): 961-965, 2021 Nov 12.
Artigo em Zh | MEDLINE | ID: mdl-34758522

RESUMO

Objective: To analyze the epidemiological characteristics of an outbreak of novel coronavirus pneumonia (COVID-19) in Shijiazhuang, Hebei Province in 2021 and to provide scientific basis for developing improved strategies to prevent and control the outbreak of COVID-19. Methods: Descriptive analysis of the outbreak of COVID-19 in Shijiazhuang, Hebei Province was performed with SPSS 21.0 and Excel software. The statistical analysis of the incubation period was performed using the rstan package in R4.0.4. Results: As of February 14th 2021, a total of 942 local confirmed cases were reported in Hebei Province, 869 cases in Shijiazhuang, of which 847 cases were available for case information. This outbreak was mainly in rural areas, with the largest number of confirmed cases in Xiaoguozhuang village, 249 (29.4%); followed by Nanqiaozhai village, 128 (15.1%); and Liujiazuo village, 85 (10.0%). The outbreak lasted from January 2nd, 2021 to February 14th, 2021, and was mainly transmitted among the farmers as well as the students through dining parties, public gatherings and family contacts, showing an obvious time and occupation concentration trend. An analysis of 116 local confirmed cases in this outbreak with specific exposure time and onset time indicated that the median incubation period was 6 [interquartile range(IQR): 3.3, 10.0] days; whereas another report including 264 local confirmed cases with specific exposure time window showed that a median incubation period was 8.5 [95% confidence interval (CI): 1.8-18.8] days. Conclusions: This outbreak was mainly related to rural areas, and was associated with parties, public gatherings and family gatherings. Self-protection and isolation of key areas and populations at risk should be effectively implemented to avoid close contact and other measures to reduce the occurrence of COVID-19 aggregation. Based on the results of the incubation period of this outbreak, the isolation period could be recommended to be extended to three weeks.


Assuntos
COVID-19 , SARS-CoV-2 , China/epidemiologia , Surtos de Doenças , Humanos
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