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The impacts of various drought types on autumn phenology have yet to be extensively explored. We address the influence of pre-season agricultural and meteorological droughts on autumn phenology in the Northern Hemisphere. To this end, enhanced autumn phenology models incorporating drought factors was developed, contributing to a deeper understanding of these complex interactions. The study reveals that there was no significant trend of advancement or delay in the End of Season (EOS) across the Northern Hemisphere based on SIF estimates from 2001 to 2020. The cumulative and delayed impacts of pre-season agricultural drought on EOS were found to be more pronounced than those associated with meteorological drought. The analysis of various evaluation indexes shows that the performance of the Cooling Degree Days (CDD) model incorporating the Standardized Soil Moisture Drought Index (CDDSSMI) in simulating EOS in the Northern Hemisphere is >14 % higher than that of the standard CDD model. Additionally, the performance of the CDD model with the Standardized Precipitation Index (CDDSPI) in simulating EOS in the Northern Hemisphere is improved by >5.6 % compared to the standard CDD model. A comparison of future EOS projections across various models reveals that the CDD model significantly overestimates EOS in different scenarios (SSP245 and SSP585). The CDDSSMI model projects EOS approximately 7 days earlier than the CDD model, and the CDDSPI model projects EOS approximately 5 days earlier than the CDD model. This study highlights the diverse impacts of drought types on plant autumn phenology and underscores the significance of parameterizing drought impacts in autumn phenology models.
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Agricultura , Sequías , Estaciones del Año , Agricultura/métodos , Modelos Teóricos , Cambio Climático , Monitoreo del Ambiente/métodosRESUMEN
Self-melting ice asphalt pavement materials inhibit pavement freezing and improve driving safety. This paper aims to study the long-term salt release characteristics of self-melting ice asphalt mixtures and the impact on pavement after complete salt release. Firstly, a method to accelerate the rapid release of salt based on the Los Angeles abrasion tester. Then, long-term salt release patterns were elucidated under the influence of deicing agent dosage, type of asphalt, and type of gradation. Finally, a quantitative analysis of the pavement performance after complete salt release is conducted. The results indicate that the release efficiency of the Los Angeles abrasion tester method has increased by 91 times compared to the magnetic stirrer immersion flushing method and by 114 times compared to the natural soaking method. The SBS-modified self-melting ice asphalt mixture possesses a longer duration of salt release, but the uniformity of salt release is inferior. Salt release duration is directly proportional to the dosage of deicing agents. SMA-13 self-melting ice asphalt mixture exhibits poorer uniformity in salt release. After complete salt release, high-temperature stability of self-melting ice asphalt mixtures decreased by 31.6%, low-temperature performance decreased by 15.4%, water stability decreased by 26.7%, and fatigue life decreased by 35.9%.
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INTRODUCTION: Objective assessment of cardiac hypertrophy in forensic pathology practice is of great significance for forensic pathologists, for whom reference values for normal heart weights are needed. Developed regions such as Europe, the United States, and Japan recalculate the weight of human organs at regular intervals, but in China, there has been no systematic calculation of the weights of human organs since 2006. AIMS: To statistically analyse the heart weight of Chinese adults postmortem and obtain a reference range. MATERIALS AND METHODS: 4170 adult autopsy reports were collected from 12 forensic departments in 10 provinces in China. The causes of death were classified by sex, and heart weight and the heart weight/body height ratio reference values were further calculated according to different body mass index and body heights. Finally, the cutoff value of cardiac hypertrophy in Chinese adults was calculated. RESULTS: In the group of non-cardiovascular disease causes of death, the cardiac weight of the electric death group was higher, while the heart weight of the prolonged bed-rest group was significantly reduced. After the electric death and prolonged bed-rest groups were excluded, heart weight, the heart weight/body height ratio, and cutoff values for cardiac hypertrophy were further classified and analysed according to body mass index. The mean reference values for heart weight in men and women with normal weight status were 325.82 ± 41.60 g and 286.39 ± 44.84 g, and the heart weight/body height ratios were 1.95 ± 0.23 in men and 1.82 ± 0.27, respectively. The cutoff values for cardiac hypertrophy were 387.35 g for men and 346.80 g for women. CONCLUSION: The heart weight reference values of both sexes in this study were significantly higher than those in 2006, which is considered related to the development of China's economy and the improvement of people's living standards. This study also suggests the need for a new round of statistical surveys and updated data on the weight of other organs.
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Cardiomegalia , Corazón , Masculino , Adulto , Humanos , Femenino , Autopsia , Patologia Forense , China , Peso Corporal , Tamaño de los ÓrganosRESUMEN
OBJECTIVE: To evaluate whether the associations of maternal liver dysfunction and liver function biomarkers (LFBs) with gestational diabetes mellitus (GDM) are independent of overweight. DESIGN: Prospective cohort study. METHODS: A sub-cohort of pregnant women with seven LFBs examined at 9-13 weeks of gestation and with complete GDM evaluation at mid-gestation were extracted from the prospective Shanghai Preconception Cohort Study. Associations of liver dysfunction, defined as having any elevated LFB levels, and individual LFB levels with GDM incidence were assessed by adjusting body mass index and other covariates in the multivariable logistic regression model. Odds ratios (ORs) and 95% CI were reported. MAIN OUTCOME MEASURES: Incident GDM. RESULTS: Among 6211 pregnant women, 975 (15.7%) developed GDM. Liver dysfunction was associated with increased odds of GDM (OR 1.63; 95% CI 1.38-1.92). This association persisted after adjustment for BMI (adjusted OR [aOR] 1.37; 95% CI 1.15-1.63). Higher γ-glutamyl transferase, alanine aminotransferase, alkaline phosphatase, and albumin levels were also linked with GDM (aOR per 1 SD: 1.15, 95% CI 1.08-1.23; 1.10, 1.03-1.17; 1.21, 1.13-1.29 and 1.19, 1.11-1.27, respectively). Similar magnitudes of associations were observed between normal weight and overweight pregnant women. CONCLUSION: Maternal liver dysfunction in early pregnancy predisposes women to subsequent GDM, and this association is independent of being overweight preconception. Our findings of an increased risk even in normal-weight pregnant women adds new mechanistic insights about the pathophysiological role of liver function in GDM aetiology. TWEETABLE ABSTRACT: Maternal liver dysfunction in early pregnancy is associated with GDM incidence independent of preconception overweight.
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Diabetes Gestacional , Hepatopatías , Índice de Masa Corporal , China/epidemiología , Estudios de Cohortes , Diabetes Gestacional/epidemiología , Femenino , Humanos , Sobrepeso/complicaciones , Sobrepeso/epidemiología , Embarazo , Estudios Prospectivos , Factores de RiesgoRESUMEN
Hall-effect in semiconductors has wide applications for magnetic field sensing. Yet, a standard Hall sensor retains two problems: its linearity is affected by the non-uniformity of the current distribution; the sensitivity is bias-dependent, with linearity decreasing with increasing bias current. In order to improve the performance, we here propose a novel structure which realizes bias-free, photo-induced Hall sensors. The system consists of a semi-transparent metal Pt and a semiconductor Si or GaAs to form a Schottky contact. We systematically compared the photo-induced Schottky behaviors and Hall effects without net current flowing, depending on various magnetic fields, light intensities and wavelengths of Pt/GaAs and Pt/Si junctions. The electrical characteristics of the Schottky photo-diodes were fitted to obtain the barrier height as a function of light intensity. We show that the open-circuit Hall voltage of Pt/GaAs junction is orders of magnitude lower than that of Pt/Si, and the barrier height of GaAs is smaller. It should be attributed to the surface states in GaAs which block the carrier drifting. This work not only realizes the physical investigations of photo-induced Hall effects in Pt/GaAs and Pt/Si Schottky junctions, but also opens a new pathway for bias-free magnetic sensing with high linearity and sensitivity comparing to commercial Hall-sensors.
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OBJECTIVE: To investigate the association of folate and vitamin B12 in early pregnancy with gestational diabetes mellitus (GDM) risk. RESEARCH DESIGN AND METHODS: The data of this study were from a subcohort within the Shanghai Preconception Cohort Study. We included pregnancies with red blood cell (RBC) folate and vitamin B12 measurements at recruitment (between 9 and 13 gestational weeks) and those with three samples available for glucose measurements under an oral glucose tolerance test. GDM was diagnosed between 24 and 28 weeks' gestation. Odds ratio (OR) and 95% CI of having GDM was used to quantify the association. RESULTS: A total of 1,058 pregnant women were included, and GDM occurred in 180 (17.01%). RBC folate and vitamin B12 were significantly higher in pregnancies with GDM than those without GDM (P values were 0.045 and 0.002, respectively) and positively correlated with 1-h and 2-h serum glucose. Daily folic acid supplementation in early pregnancy increases the risk of GDM; OR (95% CI) was 1.73 (1.19-2.53) (P = 0.004). Compared with RBC folate <400 ng/mL, pregnancies with RBC folate ≥600 ng/mL were associated with â¼1.60-fold higher odds of GDM; the adjusted OR (95% CI) was 1.58 (1.03-2.41) (P = 0.033). A significant trend of risk effect on GDM risk across categories of RBC folate was observed (P trend = 0.021). Vitamin B12 was significantly associated with GDM risk (OR 1.14 per 100 pg/mL; P = 0.002). No significant association of serum folate and percentile ratio of RBC folate/vitamin B12 with GDM was observed. CONCLUSIONS: Higher maternal RBC folate and vitamin B12 levels in early pregnancy are significantly associated with GDM risk, while the balance of folate/vitamin B12 is not significantly associated with GDM.
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Diabetes Gestacional , China/epidemiología , Estudios de Cohortes , Diabetes Gestacional/epidemiología , Femenino , Ácido Fólico , Humanos , Embarazo , Estudios Prospectivos , Vitamina B 12 , VitaminasRESUMEN
Nicotinamide phosphoribosyltransferase (NAMPT) is a rate-limiting enzyme in mammalian nicotinamide adenine dinucleotide (NAD)+ biosynthesis. Through its NAD+-biosynthetic activity, NAMPT influences the activity of NAD+-dependent enzymes, such as sirtuins. NAMPT is able to modulate processes involved in the pathogenesis of non-alcohol induced fatty liver disease (NAFLD), but the roles NAMPT plays in development of alcoholic liver disease (ALD) still remain unknown. Here, we show that ethanol treatment suppresses the expression of Nampt in hepatocytes. Consistently, chronic ethanol administration also reduces Nampt expression in the mouse liver. We next demonstrate that hepatocytes infected with Ad-NAMPT adenovirus exhibit significantly elevated intracellular NAD+ levels and decreased ethanol-induced triglyceride (TG) accumulation. Similarly, adenovirus-mediated overexpression of NAMPT in mice ameliorates ethanol induced hepatic steatosis. Moreover, we demonstrate that SIRT1 is required to mediate the effects of NAMPT on reduction of hepatic TG accumulation and serum ALT, AST levels in ethanol-fed mice. Our results provide important insights in targeting NAMPT for treating alcoholic fatty liver disease.
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Citocinas/metabolismo , Hígado Graso Alcohólico/metabolismo , Hígado Graso Alcohólico/terapia , Nicotinamida Fosforribosiltransferasa/metabolismo , Adenoviridae/genética , Animales , Células Cultivadas , Citocinas/genética , Citocinas/uso terapéutico , Modelos Animales de Enfermedad , Regulación hacia Abajo/efectos de los fármacos , Etanol/toxicidad , Hígado Graso Alcohólico/genética , Técnicas de Silenciamiento del Gen , Terapia Genética , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , NAD/metabolismo , Nicotinamida Fosforribosiltransferasa/genética , Nicotinamida Fosforribosiltransferasa/uso terapéutico , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Recombinantes de Fusión/uso terapéutico , Sirtuina 1/antagonistas & inhibidores , Sirtuina 1/genética , Sirtuina 1/metabolismo , Sirtuinas/deficiencia , Sirtuinas/genética , Sirtuinas/metabolismo , Triglicéridos/metabolismo , Regulación hacia ArribaRESUMEN
Chronic exposure of pancreatic ß-cells to abnormally elevated levels of free fatty acids can lead to ß-cell dysfunction and even apoptosis, contributing to type 2 diabetes pathogenesis. In pancreatic ß-cells, sirtuin 6 (SIRT6) has been shown to regulate insulin secretion in response to glucose stimulation. However, the roles played by SIRT6 in ß-cells in response to lipotoxicity remain poorly understood. Our data indicated that SIRT6 protein and mRNA levels were reduced in islets from diabetic and aged mice. High concentrations of palmitate (PA) also led to a decrease in SIRT6 expression in MIN6 ß-cells and resulted in cell dysfunction and apoptosis. Knockdown of Sirt6 caused an increase in cell apoptosis and impairment in insulin secretion in response to glucose in MIN6 cells even in the absence of PA exposure. Furthermore, overexpression of SIRT6 alleviated the palmitate-induced lipotoxicity with improved cell viability and increased glucose-stimulated insulin secretion. In summary, our data suggest that SIRT6 can protect against palmitate-induced ß-cell dysfunction and apoptosis.
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Apoptosis , Diabetes Mellitus Tipo 2/metabolismo , Células Secretoras de Insulina/metabolismo , Estrés Oxidativo , Sirtuinas/metabolismo , Animales , Línea Celular , Supervivencia Celular , Senescencia Celular , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/patología , Ácidos Grasos no Esterificados/efectos adversos , Regulación Enzimológica de la Expresión Génica , Hiperglucemia/metabolismo , Insulina/metabolismo , Secreción de Insulina , Células Secretoras de Insulina/patología , Islotes Pancreáticos/metabolismo , Islotes Pancreáticos/patología , Metabolismo de los Lípidos , Ratones , Ratones Mutantes , Ratones Transgénicos , Ácido Palmítico/efectos adversos , Interferencia de ARN , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Sirtuinas/antagonistas & inhibidores , Sirtuinas/genética , Técnicas de Cultivo de TejidosRESUMEN
OBJECTIVE: To investigate Fas protein expression of the myocardium in dilated cardiomyopathy (DCM) and its relationship with occurrence of sudden death caused by DCM. METHODS: Nine autopsy cases of sudden death caused by DCM along with the heart samples were chosen from the archives in the Department of Forensic Medicine, Tongji Medical College, HUST from 1997 to 2007. Other 11 cases which died of violence and other diseases were selected as the control group. Expressions of myocardial Fas protein in the samples were quantitatively detected by immunohistochemistry and computerized imaging analysis. RESULTS: Myocardial Fas protein expression increased significantly in the DCM group. Positive color showed brown-yellow granulated or striped distribution in the longitudinal section of myocardial within the cell membrane and cytoplasm, and showed circular brown granules in the cross section of the cell membrane, while these changes were not observed in the control group though there was focal weak staining noted. Statistical significance was observed between the experimental and control groups (P = 0.002), but no statistical significance was found for the average optical density value between these two groups (P = 0.675). CONCLUSION: The expression of Fas protein increased obviously in the DCM group. Such alteration in expression quantity and distribution of myocardial Fas protein may be related to arrhythmia and heart failure in the patients with DCM.