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1.
Heliyon ; 10(13): e34144, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39071693

RESUMEN

Carbon fiber reinforced composite structures have been a research hotspot in recent years, with 9 specimens designed for static tests under bending and torsion loads of CFRP concrete filled steel tubes. The torque angle (T-θ) curve was studied from an experimental perspective. Subsequently, a reasonable finite element model was established using ABAQUS software. In addition, the effects of changes in parameters such as the number of steel concrete strength, bending ratio, and steel ratio on C-CF-CFRP-ST bending and torsion specimens were studied through numerical parameter research. Finally, equations of bearing capacity of CFRP-concrete filled steel tube under coupled bending and torsion are proposed.

2.
Ying Yong Sheng Tai Xue Bao ; 34(6): 1541-1546, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37694416

RESUMEN

The development of precise climate risk zoning for chilling injury of Morchella esculenta can provide scientific basis for agricultural cultivation planning, dynamic assessment of chilling injury, and disaster prevention strategies. Based on meteorological data from 17 counties (cities) that located below the altitude of 3000 m in the Western Sichuan Plateau from 2011 to 2020, we analyzed the critical meteorological conditions for M. esculenta disasters in typical years. With the average yearly cold accumulation and cold injury frequency during the first day when the temperature remained stable between 5 ℃ and 10 ℃ during mushroom emergence as zoning indicators, we established a geographical spatial distribution model of the cold injury index, and then divided the risk level of M. esculenta cold injury in the Western Sichuan Plateau, evaluated the risk of cold injury. The results showed that the temperature index for chilling injury risk of M. esculenta in the study area was the daily minimum temperature ≤2.0 ℃. The daily average temperature <6.0 ℃ would cause slow growth or the cessation of growth, which was set as a warning indicator for chilling injury risk. Along the Dadu River and Minjiang River basins, the frequency of chilling injury on M. esculenta increased from south to north. Wenchuan, Maoxian, and Lixian had the fewest overall chilling injuries during the study period, whereas Jiulong, Yajiang, and Batang had the most. The duration for cold injury was mainly 1-3 d, followed by 4-5 d, and rarely for >5 d. The frequency of chilling injury lasting for more than 5 d in Xiangcheng, Batang, Jiulong, Yajiang, and Xiaojin was more than that lasting for 4-5 d. The annual average days of chilling injury of was 3.0-27.4 d, the daily average minimum temperature was -0.84-1.36 ℃, the extreme lowest temperature was -5.8-0.1 ℃, and the average accumulated cold was 0.16-9.64 ℃·d during the period of chilling injury. With the increases of elevation and latitude, the average days of chilling injury and the average accumulated cold increased. The largest duration of chilling injury was 3-20 d, the maximum accumulated cold was 0.44-13.34 ℃·d. The risk of chilling injury to M. esculenta increased from south to north and from low elevation to high elevation. The suitable planting areas were distributed in strips and branches along the direction of mountains and rivers, mainly in the flat areas of low mountains and valleys below the altitude of 2200 m, including Kangding, Luding, Danba, Wenchuan, Lixian, Maoxian, Jiuzhaigou, and Songpan.


Asunto(s)
Lesión por Frío , Frío , Humanos , China , Medición de Riesgo
3.
Polymers (Basel) ; 14(7)2022 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-35406346

RESUMEN

To study the behavior of square concrete-filled CFRP (carbon fiber polymer) steel tubular under bending-torsional load, nine square section concrete-filled CFRP steel tubular specimens are designed. The T-θ curve and failure mode of square concrete-filled CFRP steel tubular are studied under a bending-torsional load. Based on the test results, a finite element modeling method is proposed by using the finite element software ABAQUS, and the simulation results are compared with the experimental results. The results show that the simulation is in good agreement with the experimental results. On the basis of verifying the reliability of the model, the whole stress process and parameter analysis of the component are studied, and the calculation expression of bearing capacity of square concrete-filled CFRP steel tubular under bending-torsion load is proposed. The predicted specimen-bearing capacity of the proposed calculation expression of the bearing capacity of square concrete-filled CFRP steel tubular under bending-torsion load is basically consistent with the test results.

4.
Zhongguo Zhong Yao Za Zhi ; 47(23): 6529-6532, 2022 Dec.
Artículo en Chino | MEDLINE | ID: mdl-36604900

RESUMEN

According to Provisions for Drug Registration and Categories and Requirements of Application Dossiers for Traditional Chinese Medicine(TCM), non-clinical safety research/toxicology research should be conducted for classical compound Chinese medicine prescriptions(Categories 3.1 and 3.2), and the data should be submitted at the application for the marketing authorization. Based on the requirements of toxicology research in Categories and Requirements of Application Dossiers for Traditional Chinese Medicine, this study further refined and clarified the requirements of toxicology research on classical compound Chinese medicine preparations(Categories 3.1 and 3.2).


Asunto(s)
Medicamentos Herbarios Chinos , Medicina Tradicional China , Medicamentos Herbarios Chinos/toxicidad , Prescripciones , Prescripciones de Medicamentos
5.
Ying Yong Sheng Tai Xue Bao ; 32(7): 2525-2533, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34313071

RESUMEN

Based on the distribution data of Tricholoma matsutake obtained from field investigation and literature, the ecological-niche factor analysis (ENFA) and the maximum entropy model (MaxEnt) were used to simulate the distribution law and suitable area of T. matsutake in the western Sichuan Plateau. The prediction was made for the future changes in the suitable area of T. matsutake by analyzing the relationship between climate factors and dynamic distribution. The results showed that the area under curve (AUC) values of both the model training set and validation set were greater than 0.90, indicating that the model prediction results were extremely accurate. The environmental variables affecting the potential distribution of T. matsutake were mainly the lowest temperature in the coldest month, the coldest season precipitation, annual temperature difference and soil type, with accumulative contribution of 90.3%. The niche parameters of suitable distribution areas of T. matsutake were as follows: the lowest temperature in the coldest month was -18.5--5.4 ℃, the coldest season precipitation was less than 15.7 mm, the annual temperature difference was 39.5-45 ℃, and soil type was semi-leached soil, including dry red soil, cinnamon soil, gray cinnamon soil, black soil and grey forest soil. The suitable areas of T. matsutake were distributed in the southwest, south, central and east of the plateau at an altitude range of 1900-3600 m. The highly suita-ble areas were mainly distributed in some towns of Yajiang, Xiangcheng, Kangding, Jiulong, Daocheng, Litang, Batang, Danba, Maerkang, Xiaojin, Jinchuan, Lixian, Maoxian, etc. The moderately and lowly suitable areas were located in some towns of Derong, Daofu, Xinlong, Luhuo, Baiyu, Luding, Rangtang, Wenchuan, Heishui, Jiuzhaigou. The highly suitable areas were discontinuously distributed according to the direction of rivers and mountains. The moderately suitable areas were connected with the highly suitable areas, while the lowly suitable areas were the extension of the highly and moderately suitable areas. Future climate change would be beneficial to the growth of T. matsutake on the western Sichuan Plateau, while the climate-suitable areas would show an overall increasing trend. Suitable areas in the low-altitude Minjiang River Basin would be more affected by climate change than those located in high-altitude areas.


Asunto(s)
Tricholoma , Agaricales , China , Cambio Climático , Ecosistema
6.
Chinese Journal of School Health ; (12): 1297-1301, 2021.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-886895

RESUMEN

Objective@#To explore the adverse effects of high temperature on emergency admissions of children during the summer in Beijing.@*Methods@#Child emergency admissions was collected from 30 hospitals in Beijing during the summer of 2016-2018, as well as data related to meteorological factors and air pollutant concentrations. A generalized linear model was used to analyze the association between the daily mean temperature and emergency admissions of children due to total non accidental diseases, circulatory diseases, and respiratory diseases during the summer in Beijing.@*Results@#During the summer of 2016 to 2018 in Beijing, the daily mean temperature was (24.06±3.59)℃, and the daily mean relative humidity was (65.08±17.45)%. Every 1 ℃ increase in the daily mean temperature on the day of exposure had a significant effect on emergency admissions of children, aged 0-14 years old, due to total non accidental diseases and respiratory diseases in Beijing, such that the risk of emergency admissions increased by 0.21, 0.64 times, respectively. The effect of high temperature on emergency admissions due to circulatory diseases was not significant. High temperature had inconsistent effects on emergency admissions of children from different age groups. Among them, the largest increase in the risk of emergency admissions due to total non accidental diseases was observed among children aged 5-9 years old, while children aged 0-4 were vulnerable to emergency admissions for respiratory diseases, and emergency admissions for circulatory diseases were the highest among children aged 10-14.@*Conclusion@#High temperature had a significant effect on emergency admissions of children during the summer in Beijing. Pediatric respiratory diseases are sensitive diseases that are associated with a high temperature in summer, and greater attention should be given to this issue.

7.
Artículo en Inglés | MEDLINE | ID: mdl-31677481

RESUMEN

Amino acids play key roles in cellular protein biosynthesis and energy metabolism pathways. In this study, a simple, rapid and sensitive method was developed for the simultaneous determination of 24 free amino acids in cell samples using hydrophilic interaction liquid chromatography coupled to tandem mass spectrometry (HILIC-MS/MS). Cell samples were deproteinized with methanol/H2O (80:20, v/v) without intricate derivatization process. The analytes were separated on a Waters BEH Amide column (2.1 mm × 100 mm, 1.7 µm), and accomplished within 5 min at a flow rate of 0.2 mL/min. The good linearity was obtained for all analytes (r2 > 0.99) with the limits of quantification from 0.1 to 25 ng/mL. The intra- and inter-day precision ranged from 0.35 to 10.36% and from 2.22 to 9.93%, respectively. The recoveries of most analytes were between 80% and 120% with RSD less than 10.0%. The developed method was then applied to the direct analysis of 24 underivatized amino acids in human gastric cancer cell line MGC803 treated with the antitumor candidate drug J3, and significant differences in the concentration levels of amino acids were also assessed.


Asunto(s)
Aminoácidos/análisis , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Línea Celular Tumoral , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Lineales , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
8.
Ying Yong Sheng Tai Xue Bao ; 30(7): 2137-2144, 2019 Jul.
Artículo en Chino | MEDLINE | ID: mdl-31418215

RESUMEN

Based on the biological characteristics of Cordyceps sinensis, combined with the spatial and temporal distribution characteristics of local agro-climatic resources and the investigation data of C. sinensis resources, we investigated the ecological climate suitability regionalization and the spatial distribution of C. sinensis in Shiqu County using mathematical statistics analysis, optimization method and GIS spatial analysis. We used altitude, mean annual temperature, mean annual precipitation, vegetation, and soil as the leading indicators and topographic gradient as the auxiliary indicators, as the main basis for the suitability zoning of C. sinensis resources. The results showed that C. sinensis grew in most of the townships in Shiqu County, with their distribution areas being fragmented and scattered, showing sporadic patches and blocks. They were mainly distributed in east and west parts of the county and in the Zhaqu River basin in the central part. The suitable distribution area for C. sinensis in Shiqu was 4000-4700 m above sea level, with mean annual temperature of -2.5-3 ℃ and mean annual precipitation of 550-850 mm. The growth environment was generally alpine mea-dow and subalpine meadow with good hydrophobicity and slope of 15°-50°. The suitable growth environment and meteorological conditions were beneficial to the growth and development of feeding plants and bat moths. The unsuitable area was in the high mountain area above the river wide valley area, pastoral area, wetland, or snowline.


Asunto(s)
Cordyceps , Sistemas de Información Geográfica , China , Clima , Ecología , Suelo
9.
J Asian Nat Prod Res ; 21(5): 476-493, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-29322879

RESUMEN

Diabetic cardiomyopathy (DCM) is one of the chief diabetes mellitus complications. Inflammation factors may be one reason for the damage from DM. The purpose of this research is to study the potential protective effects of puerarin on DM and the possible mechanisms of action related to NF-κB signal pathway. Following administration of puerarin to the disease model rat, several changes were observed including the changes of serum biochemical index, improved diastolic dysfunction, and enhanced endogenous antioxidant enzymes activities, further NF-κB signaling activation. Puerarin showed cardio-protective effects on DCM by inhibiting inflammation, and it might be a potential candidate for the treatment of DCM.


Asunto(s)
Diabetes Mellitus Experimental/complicaciones , Cardiomiopatías Diabéticas/prevención & control , Inflamación/tratamiento farmacológico , Isoflavonas/farmacología , Animales , Línea Celular , Células Cultivadas , Glucosa/toxicidad , Isoflavonas/química , Estructura Molecular , Mioblastos Cardíacos/efectos de los fármacos , Miocardio/citología , FN-kappa B , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos
10.
Pediatr Neurol ; 61: 63-9, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27265460

RESUMEN

BACKGROUND: Congenital insensitivity to pain with anhidrosis is an extremely rare hereditary disorder linked to variants in NTRK1. Our goal was to characterize the clinical features and the genetic basis of the disorder in Chinese patients. METHODS: Patients were enrolled via social networking. Clinical features were investigated by interview, chart review, and physical examination. DNA was extracted from peripheral blood to genotype NTRK1 in patients and their parents. Variants identified were checked against a control cohort by high-throughput sequencing, and the effects of these variants were assessed in silico. RESULTS: Clinical features in five patients were cataloged, and six loss-of-function NTRK1 variants were identified, including a frameshift variant c.963delG, a nonsense variant c.1804C>T, an intron variant c.851-33T>A, and three missense variants c.1802T>G, c.2074C>T, and c.2311C>T. CONCLUSIONS: The results expand the spectrum of clinical and genetic features of congenital insensitivity to pain with anhidrosis and will help facilitate analysis of genotype-phenotype association in the future.


Asunto(s)
Neuropatías Hereditarias Sensoriales y Autónomas/genética , Neuropatías Hereditarias Sensoriales y Autónomas/fisiopatología , Receptor trkA/genética , Niño , Preescolar , Femenino , Genotipo , Humanos , Mutación con Pérdida de Función , Masculino , Fenotipo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Adulto Joven
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