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1.
Sci Rep ; 14(1): 8549, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609459

RESUMEN

To study the effect of internal particle size on the microstructure properties and thermal decomposition characteristics of site mixed emulsion explosive at different altitudes. Site mixed emulsion explosive was prepared with different shear rate. The particle size, viscosity, sensitized bubbles, detonation velocity and peak pressure of the emulsion explosive were tested after stored at different simulated altitudes. The thermal decomposition characteristics of emulsion matrix prepared at three different rotational speeds were measured by thermogravimetric analyzer and kinetic analysis was performed by non-isothermal model Kissinger-Akah-Sunose (KAS) method. The results show that with the increase in altitude, the internal phase size showed a trend of first increasing and then decreasing, and the number of sensitized bubbles within the emulsion explosive decreases. At an altitude of 0 m, the detonation velocity and peak overpressure of the emulsion explosive prepared by 1600 r min-1 increased 4.78% and 29.09%, respectively compared with 1200 r min-1, and at an altitude of 4500 m, the detonation velocity increased 11.87%, the peak overpressure increased 43.98%. The thermal decomposition activation energy of the emulsion matrix at 1600 r min-1 increased 13.14% compared to 1200 r min-1. It shows that in the production of site mixed emulsion explosive at high altitude, reducing the particle size of the internal phase of emulsion explosives in a certain range can effectively improve the performance of emulsion explosives.

2.
Zhonghua Yi Xue Za Zhi ; 103(47): 3842-3847, 2023 Dec 19.
Artículo en Chino | MEDLINE | ID: mdl-38123226

RESUMEN

Objective: To propose a method to determine the unreasonableness of the fixed angle in posterior atlantoaxial fusion surgery based on the ratio of line segments between anatomical landmarks of the atlantoaxial joint. Methods: A cross-sectional study was conducted. According to the inclusion criteria, a screening was performed on the database of asymptomatic volunteers who had full-spine lateral X-ray films taken at the Second Affiliated Hospital of Wenzhou Medical University from May 2016 to May 2021. A total of 207 volunteers were included, comprising 98 males with an age of (40.68±13.87) years and 109 females with an age of (42.64±14.45) years. On the lateral X-ray film, a line (L) parallel to the posterior margin of the odontoid process was drawn at the posterior edge of the lower articular surface of the axis (a), intersecting the atlas at points b, c, and d. The line segments ab, bd, bc, and the C1-C2 angle were measured, and the ratios of bd/ab and bc/ab were calculated. The ability of bd/ab and bc/ab to predict the unreasonable fixed angle of the atlantoaxial joint (≥22°) was analyzed by receiver operating characteristic (ROC) curve analysis in both male and female. The areas under the ROC curves (AUC) were calculated, and the performance of the two prediction methods was compared using the Delong's test. The cutoff value for distinguishing the unreasonableness of the C1-C2 angle and the sensitivity and specificity were calculated. Results: The ROC curve analysis in the male group showed that the AUC of bc/ab for predicting the unreasonable C1-C2 angle was 0.791 (95%CI: 0.696-0.867, P<0.001), with a cutoff value of 0.449, sensitivity of 97.3%, and specificity of 70.0%. The performance was significantly better than that of bd/ab (cutoff value 1.100, AUC=0.532, 95%CI: 0.428-0.634, sensitivity 26.3%, specificity 83.3%, P<0.001). The ROC curve analysis in the female group showed that the AUC of bc/ab for predicting the unreasonable C1-C2 angle was 0.804 (95%CI: 0.745-0.852, P<0.001), with a cutoff value of 0.488, sensitivity of 90.5%, and specificity of 58.6%. The performance was significantly better than that of bd/ab (cutoff value 0.960, AUC=0.687, 95%CI: 0.624-0.748, sensitivity 90.5%, specificity 44.8%, P=0.041). Conclusions: The bc/ab value can be used as an effective indicator to predict the unreasonable C1-C2 angle in posterior atlantoaxial fusion surgery with high diagnostic accuracy. The cutoff value for males is<0.449, and for females is<0.488.


Asunto(s)
Articulación Atlantoaxoidea , Fusión Vertebral , Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Vértebras Cervicales/cirugía , Película para Rayos X , Estudios Transversales , Tornillos Óseos , Articulación Atlantoaxoidea/cirugía , Fusión Vertebral/métodos
3.
Artículo en Chino | MEDLINE | ID: mdl-37805745

RESUMEN

Mortality due to severe burns has always been at a high level. A large number of studies have shown that the rapid onset of infectious symptoms and rapid progression of severely burned patients are closely related to the occurrence of cytokine storm. However, in clinical practice, cytokine storm monitoring, early warning, and symptomatic treatment are still in exploratory stage. This article reviews the cytokine storm and its related cytokines, the mechanism, early warning, and treatment of cytokine storm induced by burn infection, aiming to provide clinical references for reducing infection and mortality in severely burned patients.


Asunto(s)
Quemaduras , Síndrome de Liberación de Citoquinas , Humanos , Quemaduras/terapia , Quemaduras/tratamiento farmacológico , Citocinas
4.
Eur Rev Med Pharmacol Sci ; 27(18): 8762-8772, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37782188

RESUMEN

OBJECTIVE: Gestational diabetes mellitus (GDM) is a serious pregnancy complication, and women with undiagnosed diabetes mellitus can develop chronic hyperglycemia during pregnancy. The purpose of this study is to investigate the impact of information-based continuity of care on glucose levels, health awareness, and maternal and infant outcomes in pregnant women with GDM, thereby providing a basis for the clinical implementation of effective interventions for GDM to reduce or avoid adverse outcomes due to GDM. PATIENTS AND METHODS: One hundred and sixty cases of pregnant women with GDM who underwent treatment in the obstetrics and gynecology department of our hospital from June 2019 to September 2021 were randomly selected as the study population and divided into the control group (n=80) and the study group (n=80). Women in the control group were received with conventional nursing intervention, and those in the study group were obtained with information-based continuity of care on the basis of the control group. Basic clinical data were collected. The levels of fasting blood glucose (FBG), 2h postprandial glucose (2hPG), knowledge of health education, treatment compliance scores, and changes in delivery outcomes were compared between the two groups. According to the maternal blood glucose control level, 160 pregnant women with GDM were divided into the better control group (143 cases) and the poor control group (17 cases). The risk factors affecting the level of maternal glycemic control in gestational diabetes were analyzed. RESULTS: After the intervention, the levels of FBG and 2hPG were significantly lower in both groups than those before the intervention, while the levels of FBG and 2hPG in the study group were notably lower than those in the control group. The health education knowledge score and treatment compliance score after the intervention were significantly higher than those before the intervention, and the health education knowledge score and treatment compliance score in the study group were observably higher than those in the control group (p<0.01). The adverse pregnancy outcomes of pregnant women in the study group were significantly reduced compared with those in the control group (p<0.05). Logistic regression analysis showed that body mass index (BMI), dietary control, literacy, and information-based continuity of care were all influential factors for maternal glycemic control level (p<0.05). Among the influencing factors, dietary control and continuity of care had clinical value in predicting maternal glycemic control levels in gestational diabetes. CONCLUSIONS: Continuous nursing based on informatization can effectively control the blood glucose level of pregnant women with GDM, improve the treatment compliance of pregnant women and the awareness rate of gestational diabetes knowledge so as to reduce the occurrence of adverse pregnancy outcomes and improve the health level. In addition, BMI and dietary control are independent risk factors that affect the blood glucose control level of pregnant women. Relevant intervention measures should be formulated according to the relevant influencing factors to effectively control the blood glucose level of pregnant women with GDM and improve maternal and infant outcomes.


Asunto(s)
Diabetes Gestacional , Embarazo , Lactante , Humanos , Femenino , Diabetes Gestacional/terapia , Glucemia , Mujeres Embarazadas , Escolaridad , Educación en Salud
5.
Zhonghua Liu Xing Bing Xue Za Zhi ; 44(10): 1545-1551, 2023 Oct 10.
Artículo en Chino | MEDLINE | ID: mdl-37875440

RESUMEN

Objective: To analyze the association between the occurrence of spermarche and menarche and psychological distress among Chinese Han children and adolescents aged 9 to 18 years. Methods: Data were drawn from the 2019 Chinese National Survey on Students' Constitution and Health, and a total of 54 438 boys aged 11 to 18 years and 76 376 girls aged 9 to 18 years with psychological distress, spermarche/menarche records were included in the final analysis. The occurrence of spermarche/menarche was recorded by physicians, and psychological distress was classified according to the Kessler Psychological Distress Scale scores. The chi-square test was used to compare the difference between groups in the occurrence of spermarche/menarche, and the multinomial logistic regression model and stratification analysis was established to analyze the association between psychological distress and spermarche/menarche. Results: The incidence of spermarche/menarche in 2019 ranged from 6.3% to 96.5% for eight age groups of Chinese boys and 2.8% to 99.0% for ten age groups of girls. The rates of high psychological distress among boys and girls were 32.5% and 32.7%. Among boys aged 11 to 18 years, the rate of high psychological distress increased with age, with a trend test P<0.001, and the difference in the rate of high psychological distress between those who had and had not had their spermarche was not statistically significant in all age groups. Among girls aged 9 to 18 years, the rate of high psychological distress increased with age, with a trend P<0.001; the rate of high psychological distress was higher in the group with menarche at age 10 and 12 than in the group without menarche (all P<0.05). High psychological distress was positively correlated with spermarche among boys aged 13-15 years living in urban areas and hight level economic development areas (OR=1.11, 95%CI: 1.02-1.21;OR=1.18, 95%CI: 1.06-1.32). Overall, high psychological distress was positively correlated with menarche in girls aged 9-12 and 13-15 years (OR=1.33, 95%CI: 1.25-1.42; OR=1.22, 95%CI: 1.07-1.39). High psychological distress was positively correlated with menarche among girls aged 9-12 years living in different regions except for the Northeast region, in areas with different levels of economic development, and in urban and rural areas, in girls aged 13-15 years living in urban, central, and western regions, and in girls aged 16-18 years residing in the central region. Conclusions: This study found an association between the occurrence of spermarche/menarche and psychological distress among Chinese Han children and adolescents aged 9 to 18 years in 2019, which was particularly significant among girls aged 9 to 12 years and boys aged 13 to 15 years living in areas with higher levels of socioeconomic development.


Asunto(s)
Menarquia , Maduración Sexual , Masculino , Femenino , Humanos , Niño , Adolescente , Pueblo Asiatico , Modelos Logísticos , Estudiantes , China/epidemiología
6.
Zhonghua Liu Xing Bing Xue Za Zhi ; 44(10): 1537-1544, 2023 Oct 10.
Artículo en Chino | MEDLINE | ID: mdl-37875439

RESUMEN

Objective: To describe the prevalence of psychological distress and to analyze its influencing factors among Chinese children and adolescents aged 9-18 years in 2019. Methods: Data was from the 2019 Chinese National Survey on Students' Constitution and Health, and 148 892 children and adolescents were included. Psychological distress was measured using the Kessler Psychological Distress Scale (K10): scores ≤19 were defined as no psychological distress, scores between 20-24 were defined as mild psychological distress, scores between 25-29 were defined as moderate psychological distress, and scores ≥30 were defined as severe psychological distress (moderate to severe psychological distress were defined as high psychological distress). The ANOVA, t test, and χ2 test were used to compare the differences in K10 scores and high psychological distress rates among children and adolescents with different characteristics. The ANOVA and trend χ2 test were used to analyze the trends. Modified-Poisson regression models were used to determine influencing factors of high psychological distress. Results: The K10 scores for Chinese children and adolescents aged 9-18 years in 2019 was 21.5±9.2, and their rate of high psychological distress was 31.6%. The rates of high psychological distress among children and adolescents aged 9-12, 13-15, and 16-18 years were 22.3%, 35.9%, and 38.8%. K10 scores and rates of high psychological distress showed an increasing trend as age increased (trends test all P<0.001). K10 scores and rates of high psychological distress were higher among children and adolescents who were older, female, rural, in areas with medium to low GDP per capita level, and with lower parental education (all P<0.001). Multifactorial modified-Poisson regression analysis showed that children and adolescents aged 13-15 years, 16-18 years, female, rural, and in areas with low to moderate GDP per capita level were at higher risk of high psychological distress (all P<0.05), with aOR (95%CI) of 1.55 (1.52-1.58), 1.66 (1.63-1.69), 1.07 (1.05-1.09), 1.02 (1.01-1.04), 1.10 (1.07-1.12). Children and adolescents in areas with medium to high GDP per capita level, whose father had a secondary or high school degree, whose father had a college degree or above, whose mother had a secondary or high school degree, and whose mother had a college degree or above were at lower risk of high psychological distress (all P<0.05), with aOR (95%CI) of 0.96 (0.94-0.98), 0.92 (0.90-0.93), 0.84 (0.82-0.86), 0.95 (0.93-0.97), 0.86 (0.83-0.88). Conclusions: The prevalence of psychological distress was high among Chinese children and adolescents aged 9-18 years in 2019, which is a vital problem. Mental health interventions need to be implemented among children and adolescents that were older, girls, rural, live in areas with lower economic levels, and whose parents have a lower education level.


Asunto(s)
Madres , Padres , Humanos , Femenino , Adolescente , Niño , Prevalencia , Análisis de Regresión , Salud Mental , Estrés Psicológico/epidemiología
7.
Zhonghua Liu Xing Bing Xue Za Zhi ; 44(10): 1552-1557, 2023 Oct 10.
Artículo en Chino | MEDLINE | ID: mdl-37875441

RESUMEN

Objective: To describe the status of physical fitness of children and adolescents aged 13-18 years in China in 2019 and analyze its association with psychological distress. Methods: Data were drawn from the 2019 Chinese National Survey on Students' Constitution and Health, and 90 633 Han children and adolescents aged 13-18 years were included. Physical fitness was evaluated by "National Students Constitutional Health Standards" (2014 revised edition). Psychological distress was classified according to the scores of the Kessler Psychological Distress Scale: ≤19, 20-24, 25-29, and ≥30 scores indicated no, mild, moderate, and severe psychological distress, respectively, with moderate and severe psychological distress collectively referred to as high psychological distress. The χ2 test was used to compare the distribution differences between boys and girls, the Cochran-Armitage test was used to analyze the trend, and the multinomial logistic regression in the mixed effect model was established to analyze the association between physical fitness and psychological distress. Results: In 2019, the unqualified rate of physical fitness among children and adolescents aged 13-18 years in China was 17.2%, and the prevalence of excellent and good physical fitness was 18.2%, which was lower among boys (15.9%) than girls (20.5%) with a statistically significant difference (P<0.05). The excellent and good physical fitness rate showed a significantly decreasing trend with age (trend test P<0.05). The rate of high psychological distress among children and adolescents aged 13-18 years in China in 2019 was 39.3%, with boys (37.0%) having a lower prevalence than girls (41.6%), supported by a statistically significant difference (P<0.05), and a decreasing trend with the degree of physical fitness was observed both in boys and girls (trend test P<0.05). The multinomial logistic regression model showed that the prevalence of moderate (OR=0.83, 95%CI: 0.79-0.88, P<0.001) and severe (OR=0.81, 95%CI: 0.77-0.86, P<0.001) psychological distress were both lower in children and adolescents with excellent and good physical fitness. Conclusion: The status of physical fitness and psychological distress of Chinese children and adolescents aged 13-18 in 2019 was not optimistic, with physical fitness showing a significantly negative association with psychological distress.


Asunto(s)
Pueblo Asiatico , Aptitud Física , Adolescente , Femenino , Humanos , Masculino , China/epidemiología , Aptitud Física/psicología , Estudiantes , Distrés Psicológico
8.
Zhonghua Liu Xing Bing Xue Za Zhi ; 44(10): 1558-1566, 2023 Oct 10.
Artículo en Chino | MEDLINE | ID: mdl-37875442

RESUMEN

Objective: To analyze the association between overweight and obesity, psychological distress, and the influence of physical exercise among Chinese children and adolescents. Methods: The study used data from the 2019 Chinese National Survey on Students' Constitution and Health. A total of 95 280 Han Chinese children and adolescents aged 13 to 18 years were included in the study based on complete information on overweight and obesity, psychological distress assessment, and physical exercise variables. The Kessler Psychological Distress Scale was used to measure their psychological distress, with scores above 25 indicating high psychological distress. The BMI group of the adolescents was evaluated according to the Chinese standard "WS/T 586-2018 Screening for Overweight and Obesity in School-age Children and Adolescents", including underweight, normal weight, overweight, and obesity. The individual's BMI Z-score (BMIZ) was evaluated using the WHO standard and divided into ten groups based on the population percentile distribution. The survey collected the subjects' average daily physical exercise time and divided them into two groups: less than 1 hour and greater than or equal to 1 hour. Logistic regression analysis was used to analyze the relationship between overweight and obesity and high psychological distress among children and adolescents and the differences in association between different physical exercise groups. Results: The detection rates of overweight and obesity among Han Chinese children and adolescents aged 13 to 18 years in 2019 were 14.5%, and 7.6%, respectively. The rate of high psychological distress was 37.6%, and the rate of average daily physical exercise time exceeding 1 hour was 17.1%. Using the population with a BMIZ P10 below as a reference, the association strength between high psychological distress and the population gradually increased, with an OR (95%CI) value of 1.08 (1.02-1.14), 1.09 (1.02-1.14), 1.10 (1.03-1.16), and 1.16 (1.09-1.23) for BMIZ in the P60-, P70-, P80-, >P90 groups. Compared to normal weight, both overweight and obesity were positively associated with high psychological distress in children and adolescents, with obesity showing a more significant correlation, while underweight was negatively associated with high psychological distress. The detection rates of high psychological distress in normal weight, underweight, overweight, and obese groups were 37.6%, 37.0%, 38.2%, and 38.7%, respectively, with an OR (95%CI) value of 0.93 (0.88-0.98) for the underweight group and 1.05 (1.01-1.10) and 1.13 (1.07-1.19) for the overweight and obese groups, respectively. The positive correlation between BMIZ, overweight, and obesity with high psychological distress was significant only in adolescents who exercised less than 1 hour per day on average. Conclusions: Chinese children and adolescents face the problem of obesity and high psychological distress, with a positive correlation between these two problems. Physical activity may moderate the association between obesity and psychological distress in children and adolescents. Adequate physical exercise may offset the potential high psychological distress caused by obesity in children and adolescents. Thus, strengthening physical exercise among children and adolescents reduces the risks of both obesity and psychological health problems effectively.


Asunto(s)
Sobrepeso , Obesidad Infantil , Niño , Adolescente , Humanos , Sobrepeso/epidemiología , Sobrepeso/psicología , Obesidad Infantil/epidemiología , Delgadez , Estudiantes , Ejercicio Físico , Índice de Masa Corporal
9.
Zhonghua Liu Xing Bing Xue Za Zhi ; 44(10): 1567-1574, 2023 Oct 10.
Artículo en Chino | MEDLINE | ID: mdl-37875443

RESUMEN

Objective: To evaluate the level of psychological distress among Chinese children and adolescents and analyze its lifestyle influencing factors. Methods: Data were obtained from the 2019 Chinese National Survey on Students' Constitution and Health. A lotal of 120 285 Han Chinese children and adolescents aged 9-18 years with complete information on the psychological distress scale and lifestyle factors were selected, including 58 432 boys and 61 853 girls. The Kessler Psychological Distress Scale (K10) measured psychological distress, and lifestyles such as physical activity, sedentary behavior, diet, and sleep were also investigated. K10 scores of different genders were compared using the t-test, and the levels of psychological distress were compared using the χ2 test. Logistic regression was used to analyze lifestyle risk factors associated with high psychological distress, and multiple linear regression was used to find the relationship between K10 scores and lifestyle scores. Results: The average K10 score for Han Chinese children and adolescents aged 9-18 years was 21.25±7.35, with girls (21.43±7.35) scoring higher than boys (21.06±7.36), the difference was statistically significant (t=8.72, P<0.001). The rate of high psychological distress was 29.81%, with girls (31.08%) reporting higher rates than boys (28.46%), the difference was statistically significant (χ2=98.54,P<0.001). 56.10% of children and adolescents have unhealthy lifestyles, with girls (58.77%) reporting higher rates than boys (53.27%), the difference was statistically significant (χ2=368.53,P<0.001). Except for insufficient outdoor activities for girls (P=0.128), lifestyles such as insufficient physical activity, insufficient muscle-and-bone exercises, long screen time, not eating breakfast, eggs and dairy products every day, drinking sugary beverages once or more per day, and not having enough sleep are all risk factors for high psychological distress (all P<0.001). For every additional healthy lifestyle score, the K10 score decreased by 0.98 [ß=-0.98 (95%CI: -1.01- -0.95)] points (P<0.001). K10 scores in each region negatively correlate with lifestyle scores (all P<0.001). Among them, the K10 score in the eastern region showed the slightest decrease as the lifestyle score increased, while the western region showed the most decrease. Conclusions: The prevalence of psychological distress and unhealthy lifestyle in Chinese children and adolescents are high and interrelated. Compared those with healthy lifestyles, children and adolescents with unhealthy lifestyles are at greater risk of high psychological distress. Therefore, promoting healthy lifestyles for children and adolescents may be one of the important ways to improve their mental health.


Asunto(s)
Estilo de Vida , Sueño , Humanos , Masculino , Femenino , Adolescente , Niño , Ejercicio Físico , Salud Mental , Estilo de Vida Saludable
10.
Rev Sci Instrum ; 94(6)2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37862534

RESUMEN

Plasma Position Reflectometry (PPR) is planned to provide plasma position and shape information for plasma operation in future fusion reactors. Its primary function is to calibrate the drift of the magnetic signals due to the integral nature of magnetic measurement. Here, we attempt to measure plasma position using ordinary mode (O-mode) and extraordinary mode (X-mode) reflectometry systems on two tokamaks. A new physical model based on the phase shift is proposed to deduce the relative movement of the cut-off layer without density inversion. We demonstrate the plasma position measurements by absolute measurement from density profile inversion and relative measurement from phase shift. The combination of X-mode and O-mode reflectometers can minimize the limitations of single polarization reflectometry and further increase the accuracy of plasma position measurement. These results could provide an important technical basis for the further development of a real-time control system based on PPR.

11.
Zhonghua Jie He He Hu Xi Za Zhi ; 46(10): 1022-1027, 2023 Oct 12.
Artículo en Chino | MEDLINE | ID: mdl-37752047

RESUMEN

Chronic cough is a common complaint in respiratory specialist clinics, with a significant impact on cough-specific quality of life and psychophysiological health. The diagnosis, treatment and management of chronic cough remains a major challenge. We summarized a series of recent advances from clinical studies in the epidemiology, diagnosis and management of chronic cough over the past year.


Asunto(s)
Tos , Calidad de Vida , Humanos , Tos/diagnóstico , Tos/etiología , Tos/terapia
12.
Nat Commun ; 14(1): 4563, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37507388

RESUMEN

Band topology of materials describes the extent Bloch wavefunctions are twisted in momentum space. Such descriptions rely on a set of topological invariants, generally referred to as topological charges, which form a characteristic class in the mathematical structure of fiber bundles associated with the Bloch wavefunctions. For example, the celebrated Chern number and its variants belong to the Chern class, characterizing topological charges for complex Bloch wavefunctions. Nevertheless, under the space-time inversion symmetry, Bloch wavefunctions can be purely real in the entire momentum space; consequently, their topological classification does not fall into the Chern class, but requires another characteristic class known as the Stiefel-Whitney class. Here, in a three-dimensional acoustic crystal, we demonstrate a topological nodal-line semimetal that is characterized by a doublet of topological charges, the first and second Stiefel-Whitney numbers, simultaneously. Such a doubly charged nodal line gives rise to a doubled bulk-boundary correspondence-while the first Stiefel-Whitney number induces ordinary drumhead states of the nodal line, the second Stiefel-Whitney number supports hinge Fermi arc states at odd inversion-related pairs of hinges. These results experimentally validate the two Stiefel-Whitney topological charges and demonstrate their unique bulk-boundary correspondence in a physical system.

13.
Phys Rev Lett ; 130(25): 256601, 2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37418718

RESUMEN

As a fundamental concept of all crystals, space groups are partitioned into symmorphic groups and nonsymmorphic groups. Each nonsymmorphic group contains glide reflections or screw rotations with fractional lattice translations, which are absent in symmorphic groups. Although nonsymmorphic groups ubiquitously exist on real-space lattices, on the reciprocal lattices in momentum space, the ordinary theory only allows symmorphic groups. In this work, we develop a novel theory for momentum-space nonsymmorphic space groups (k-NSGs), utilizing the projective representations of space groups. The theory is quite general: Given any k-NSGs in any dimensions, it can identify the real-space symmorphic space groups (r-SSGs) and construct the corresponding projective representation of the r-SSG that leads to the k-NSG. To demonstrate the broad applicability of our theory, we show these projective representations and therefore all k-NSGs can be realized by gauge fluxes over real-space lattices. Our work fundamentally extends the framework of crystal symmetry, and therefore can accordingly extend any theory based on crystal symmetry, for instance, the classification crystalline topological phases.

14.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(3): 421-428, 2023 Jun 18.
Artículo en Chino | MEDLINE | ID: mdl-37291916

RESUMEN

OBJECTIVE: To analyze the association between outdoor artificial light-at-night (ALAN) exposure and overweight and obesity among children and adolescents aged 9 to 18 years in China. METHODS: Using follow-up data of 5 540 children and adolescents aged 9 to 18 years conducted from November 2019 to November 2020 in eight provinces of China, latitude and longitude were determined based on school addresses, and the mean monthly average nighttime irradiance at the location of 116 schools was extracted by the nearest neighbor method to obtain the mean outdoor ALAN exposure [unit: nW/(cm2·sr)] for each school. Four indicators of overweight and obesity outcomes were included: Baseline overweight and obesity, persistent overweight and obesity, overweight and obesity progression and overweight and obesity incidence. Mixed effects Logistic regression was used to explore the association between ALAN exposure levels (divided into quintiles Q1-Q5) and baseline overweight and obesity, persistent overweight and obesity, overweight and obesity progression and overweight and obesity incidence. In addition, a natural cubic spline function was used to explore the exposure response association between ALAN exposure (a continuous variable) and the outcomes. RESULTS: The prevalence of baseline overweight and obesity, persistent overweight and obesity, overweight and obesity progression and overweight and obesity incidence among the children and adolescents in this study were 21.6%, 16.3%, 2.9% and 12.8%, respectively. The OR value for the association between ALAN exposure and baseline overweight and obesity was statistically significant when ALAN exposure levels reached Q4 or Q5, 1.90 (95%CI: 1.26-2.86) and 1.77 (95%CI: 1.11-2.83), respectively, compared with the children and adolescents in the Q1 group of ALAN exposure. Similar to the results for baseline overweight and obesity, the OR values for the association with persistent overweight and obesity were 1.89 (95%CI: 1.20-2.99) and 1.82 (95%CI: 1.08-3.06) when ALAN exposure levels reached Q4 or Q5, respectively, but none of the OR values for the association between ALAN and overweight and obesity progression and overweight and obesity incidence were statistically significant. Fitting a natural cubic spline function showed a non-linear trend between ALAN exposure and persistent overweight and obesity. CONCLUSION: There is a positive association between ALAN exposure and overweight and obesity in children and adolescents, and the promotion of overweight obesity in children and adolescents by ALAN tends to have a cumulative effect rather than an immediate effect. In the future, while focusing on the common risk factors for overweight and obesity in children and adolescents, there is a need to improve the overweight and obesity-causing nighttime light exposure environment.


Asunto(s)
Sobrepeso , Obesidad Infantil , Humanos , Adolescente , Niño , Sobrepeso/epidemiología , Sobrepeso/etiología , Obesidad Infantil/epidemiología , Obesidad Infantil/etiología , Contaminación Lumínica , Factores de Riesgo , China/epidemiología
15.
Phys Rev Lett ; 130(16): 161802, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37154643

RESUMEN

We present a new determination of the smallest neutrino mixing angle θ_{13} and the mass-squared difference Δm_{32}^{2} using a final sample of 5.55×10^{6} inverse beta-decay (IBD) candidates with the final-state neutron captured on gadolinium. This sample is selected from the complete dataset obtained by the Daya Bay reactor neutrino experiment in 3158 days of operation. Compared to the previous Daya Bay results, selection of IBD candidates has been optimized, energy calibration refined, and treatment of backgrounds further improved. The resulting oscillation parameters are sin^{2}2θ_{13}=0.0851±0.0024, Δm_{32}^{2}=(2.466±0.060)×10^{-3} eV^{2} for the normal mass ordering or Δm_{32}^{2}=-(2.571±0.060)×10^{-3} eV^{2} for the inverted mass ordering.

16.
J Dent Res ; 102(7): 814-824, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37204148

RESUMEN

Subclinical hypothyroidism (SCH) has been shown to be associated with microbiota. However, the association between SCH and oral microbiota has not yet been elucidated. The results of our previous clinical studies showed that Prevotella intermedia was abundant in the oral microbiota of SCH patients. This study aimed to investigate the relationship between SCH and oral microbiota, verify the pathogenicity of P. intermedia in SCH, and preliminarily explore the possible mechanism. The SCH mouse model with oral application of P. intermedia was established, and the variance in the mouse oral microbiota and changes in thyroid function and metabolism were detected in mice. Student's t test and analysis of variance were used for statistical analysis. Oral application of P. intermedia changed the composition of the oral microbiota of SCH mice, which enhanced the damage to the thyroid and decreased the expression of functional genes of the thyroid. Moreover, P. intermedia decreased oxygen consumption and aggravated glucose and lipid metabolism disorders in SCH mice. Glucose tolerance and insulin tolerance decreased, and the triglyceride content of the liver and inflammatory infiltration in adipose tissue increased in SCH mice after P. intermedia stimulation. Mechanistically, P. intermedia increased the proportion of CD4+ T cells in cervical lymph nodes and thyroids in SCH mice. Th1 cells were suggested to play an important role in the pathogenesis of SCH involving P. intermedia. In conclusion, P. intermedia aggravated SCH manifestations, including thyroid dysfunction and glucose and lipid metabolism disorders, by causing immune imbalance in mice. This study sheds new light on the pathogenesis of SCH from the perspective of oral microbiota.


Asunto(s)
Hipotiroidismo , Trastornos del Metabolismo de los Lípidos , Ratones , Animales , Prevotella intermedia , Hipotiroidismo/complicaciones , Hipotiroidismo/metabolismo , Trastornos del Metabolismo de los Lípidos/complicaciones , Glucosa
17.
Nat Commun ; 14(1): 743, 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36765052

RESUMEN

A peculiar feature of quantum states is that they may embody so-called projective representations of symmetries rather than ordinary representations. Projective representations of space groups-the defining symmetry of crystals-remain largely unexplored. Despite recent advances in artificial crystals, whose intrinsic gauge structures necessarily require a projective description, a unified theory is yet to be established. Here, we establish such a unified theory by exhaustively classifying and representing all 458 projective symmetry algebras of time-reversal-invariant crystals from 17 wallpaper groups in two dimensions-189 of which are algebraically non-equivalent. We discover three physical signatures resulting from projective symmetry algebras, including the shift of high-symmetry momenta, an enforced nontrivial Zak phase, and a spinless eight-fold nodal point. Our work offers a theoretical foundation for the field of artificial crystals and opens the door to a wealth of topological states and phenomena beyond the existing paradigms.

18.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(12): 2064-2067, 2023 Dec 06.
Artículo en Chino | MEDLINE | ID: mdl-38186157

RESUMEN

Seasonal influenza leads to a significant disease burden, and older people infected with influenza are susceptible to various complications. Influenza immunization can prevent infection effectively and significantly reduce the risk of complications and severe cases. Creating a supportive environment for vaccination is crucial in advancing the influenza vaccination rate among the elderly population. In China, the present environment for supporting influenza vaccinations among the elderly is primarily comprised of policies for free vaccination and expense reimbursement, which exhibit noteworthy regional variations across cities and regions. This study systematically analyses the supportive environment and regional disparities associated with influenza vaccination among the elderly in China. It aims to comprehend the opportunities for influenza prevention and control resulting from the current background of influenza vaccination and to identify potential health inequality challenges caused by regional differences. The findings should inform the introduction of relevant national policies and programs to protect the health and well-being of the elderly population.


Asunto(s)
Disparidades en el Estado de Salud , Gripe Humana , Humanos , Anciano , Gripe Humana/prevención & control , China , Ciudades , Vacunación
19.
J Physiol Pharmacol ; 74(6)2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38345443

RESUMEN

We explored the involvement of orphan nuclear receptor 4 A1 (NR4A1) in myocardial fibrosis mediated by transforming growth factor-beta1 (TGF-ß1) and its response to cytosporone B (Csn-B). We developed a diabetic cardiomyopathy mouse model by administering a high-fat diet in conjunction with a low-dose streptozotocin injection. Our analysis involved monitoring alterations in blood glucose and lipid levels, cardiac function and structure, as well as profibrotic factors such as α smooth muscle actin (α-SMA), collagen I, collagen III, TGF-ß1, connective tissue growth factor, and fibronectin. These assessments were conducted using biochemical techniques, Doppler ultrasound, histopathology, and real-time quantitative polymerase chain reaction. Cardiac fibroblasts (CFs) were extracted from suckling mice and cultivated in a high-glucose medium to simulate diabetes-induced myocardial fibrosis in vitro. These CFs were then subjected to coculture experiments with TGF-ß1 or Csn-B. The proliferation and migration of CFs were assessed using cell counting kit 8 (CCK-8) assays and Transwell assays, respectively. Western blotting and immunofluorescence assays were employed to evaluate the expression levels of NR4A1, p-NR4A1, and α-SMA in CFs treated with TGF-ß1 after NR4A1 knockdown or Csn-B administration, respectively. In diabetic heart tissue, the expression of p-NR4A1 was notably elevated. Furthermore, CFs exhibited enhanced proliferative capabilities and increased p-NR4A1 expression following high glucose exposure. Interestingly, NR4A1 knockdown resulted in a significant increase in the expression of fibrosis-related proteins in CFs following treatment with TGF-ß1. Moreover, our observations revealed a marked decrease in p-NR4A1 levels and a reduction in the expression of fibrosis-related proteins after Csn-B treatment. In diabetic mice treated with Csn-B, we noted diminished NR4A1 phosphorylation and a mitigation of myocardial fibrosis. We concluded that in the mouse model, Csn-B played a pivotal role in inhibiting diabetes-induced myocardial fibrosis by activating NR4A1.


Asunto(s)
Diabetes Mellitus Experimental , Fenilacetatos , Factor de Crecimiento Transformador beta1 , Animales , Ratones , Colágeno/metabolismo , Diabetes Mellitus Experimental/metabolismo , Modelos Animales de Enfermedad , Fibroblastos/metabolismo , Fibrosis , Glucosa/metabolismo , Receptores Nucleares Huérfanos/metabolismo
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