•A general thermo-elastoplastic constitutive theory is proposed.•Physical properties’ derivatives are the connections between heat conduction and elastoplastic procedure.•The theory incorporates both ...direct and induced nonlinear effects.•The loading criteria and the drucker's stability postulates are modified.•The accuracy and efficiency of theory is higher than the conventional theory.
The thermal sensitive materials' temperature-dependent properties are the connections between thermal propagation and elastoplastic deformation, since their temperature derivatives further induce complicated nonlinearity. Incorporating the induced nonlinearity, a general thermo-elastoplastic constitutive theory is proposed. Following the theory, loading criteria, elastic trial methods and the Drucker's stability postulates are modified accordingly. As general form of the conventional theory, the general thermo-elastoplastic constitutive theory strictly conforms with mathematical principles, physical nature of material's thermo-elastoplastic behaviors and properties' temperature-dependency; thus, the general theory's accuracy is promoted by a margin of 50.4% while the computational time is slightly elevated by 10.4% in the welding experiment. Tensile test reveals that the general theory's results are more stable and reliable; however, the conventional theory produces thermo-elastoplastic evolution faster than the general theory, which is the reason for the welding experiment's suspicious and erroneous patterns. Besides, it is also demonstrated that the induced nonlinearity dominates the evolution of stress tensor with elevation of thermal effect.
Sediments from a remote lake of northeastern Tibetan Plateau were analyzed for polycyclic aromatic hydrocarbons (PAHs) and trace metals. USEPA priority PAHs, ranged from 11 in 1860 to 279 ng g
−1 in ...2002, while, the deposition fluxes were in the range of 0.2–11.4 ng cm
−2 yr
−1. Similarly, from 1860 to 2002, an increased trend of Hg flux was observed (0.5–3.2 ng cm
−2 yr
−1). Remarkable increase of PAHs and Hg concentration began from 1970, nearly the same period of the “Reform and Open” Policy had been embarked (1978) in China. Good correlations were found between concentrations of Pb, Zn, Cd, As, Hg, and PAHs, which suggested the sources of these chemicals in the sediment is analogous, likely from anthroprogenic sources. Based on isomer ratios, PAHs in core were dominantly from the incomplete combustion of coal. Owing to the proximity to dust source area (Qaidam Basin) and the close association between PAHs, Hg, Pb, and particle matters, atmospheric dust-transport and deposition might be the main pathways that pollutants enter into Qinghai Lake.
The historical deposition records of PAHs and Hg followed the economical development stages of China and sources of PAHs and Hg are dominantly pyrogenic.
Erectile dysfunction (ED) is an underappreciated clinical condition in men. This study aims to compare the dynamic changes in the distribution of ED among male kidney transplant recipients (mKTRs) in ...four epochs: end-stage renal disease period (ESRDp), early post-transplant period (EPTP), pre-COVID-19, and post-COVID-19. General information was gathered through interviews, follow-ups, and medical records. The International Index of Erectile Function Questionnaire-5 was used to assess erectile function. The Mann-Whitney U test and chi-square test were used to analyze differences in ED strength. Univariate and logistic regression analyses were conducted to identify risk factors for ED. The database contains 230 mKTRs. In the ESRDp, 17.0% had normal erectile function, 53.5% had mild ED, 18.3% had moderate ED, and 11.3% had severe ED. In the EPTP, the distribution was 38.2% normal, 42.6% mild, 10.8% moderate, and 8.2% severe. In the pre-COVID-19 period, it was 34.3%, 47.3%, 10.4%, and 7.8%, and in the post-COVID-19 period, it was 23.0%, 45.6%, 21.3%, and 10.0%. Overall, erectile function improved after kidney transplant (KT). However, post-COVID-19, the proportion of erectile function significantly decreased compared to EPTP and pre-COVID-19 periods. Risk factors for post-pandemic ED included degree, Generalized Anxiexy Disorder-7, kidney donor type, postoperative time, hypertension and hemoglobin concentration. KT improves erectile function in mKTRs within 5 years, but post-SARS-CoV-2 viral infection, ED worsens due to altered risk factors. These findings inform future research for comprehensive ED prevention and management strategies in this population.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Surgical resection remains primary curative treatment for patients with hepatocellular carcinoma (HCC) while over 50% of patients experience recurrence, which calls for individualized recurrence ...prediction and early surveillance. This study aimed to develop a machine learning prognostic model to identify high-risk patients after surgical resection and to review importance of variables in different time intervals. The patients in this study were from two centers including Eastern Hepatobiliary Surgery Hospital (EHSH) and Mengchao Hepatobiliary Hospital (MHH). The best-performed model was determined, validated, and applied to each time interval (0-1 year, 1-2 years, 2-3 years, and 3-5 years). Importance scores were used to illustrate feature importance in different time intervals. In addition, a risk heat map was constructed which visually depicted the risk of recurrence in different years. A total of 7,919 patients from two centers were included, of which 3,359 and 230 patients experienced recurrence, metastasis or died during the follow-up time in the EHSH and MHH datasets, respectively. The XGBoost model achieved the best discrimination with a c-index of 0.713 in internal validation cohort. Kaplan-Meier curves succeed to stratify external validation cohort into different risk groups (p < 0.05 in all comparisons). Tumor characteristics contribute more to HCC relapse in 0 to 1 year while HBV infection and smoking affect patients' outcome largely in 3 to 5 years. Based on machine learning prediction model, the peak of recurrence can be predicted for individual HCC patients. Therefore, clinicians can apply it to personalize the management of postoperative survival.
Metals exposure from natural environment and pollution have been linked to cardiovascular disease (CVD). However, whether associations existing between plasma multiple metals and incident ...cardiovascular disease in patients with type 2 diabetes (T2D) is unknown.
We conducted a prospective cohort study to investigate whether plasma levels of metals are associated with incident CVD risk in patients with T2D.
In a prospective study of 3897 type 2 diabetes embedded in the Dongfeng–Tongji cohort, fasting blood samples were collected in 2008 at baseline and in 2013 in the first follow-up period. Plasma concentrations of 23 metals were measured by inductively coupled plasma mass spectrometry (ICP-MS). The associations between plasma metal concentrations and CVD risk in patients with T2D were investigated with Cox proportional hazards models.
During an average of 6.2 years follow-up, 1114 participants developed CVD. In the single-metal models adjusting for established cardiovascular risk factors, plasma zinc and selenium levels were negatively and strontium was positively associated with incident CVD risk in patients with T2D. Similar results were obtained in the multiple-metal model, the HRs (95% CIs) for zinc, selenium, and strontium comparing extreme quartiles were 0.78 (95% CI: 0.65–0.93; P trend = 0.011), 0.76 (95% CI: 0.64–0.91; P trend = 0.001), and 1.51 (95% CI: 1.26–1.81; P trend <0.001), respectively. In the joint association analyses of two metals, individuals with high plasma levels of zinc and selenium had significantly lower risk of incident CVD in patients with T2D than those with low levels (HR = 0.77, 95% CI: 0.65–0.91).
The present study suggested that plasma levels of zinc and selenium had an inverse association with incident CVD risk in patients with T2D, while strontium had a positive correlation. Plasma zinc and selenium combinedly decreased incident CVD risk in patients with T2D. Further research is still needed to verify these findings in other populations.
•We investigate the association between plasma levels of metals and incident CVD risk in patients with T2D.•Plasma zinc and selenium were negatively and strontium was positively associated with incident CVD risk among T2D cases.•Plasma zinc and selenium combinedly greatly decreased incident CVD risk in patients with T2D.
The presence of gallstone disease (GSD) was reported to be positively associated with diabetes risk. Whether the association is causal remains unclear. We aim to examine the potential causal ...association between GSD and type 2 diabetes risk using a Mendelian randomization analysis. Observational study was conducted among 16,299 participants who were free of cancer, heart disease, stroke, and diabetes at baseline in the Dongfeng‐Tongji cohort study. GSD was diagnosed by experienced physicians by abdominal B‐type ultrasound inspection and type 2 diabetes was defined according to the criteria of the American Diabetes Association. Cox proportional hazard regression model was used to examine the association of GSD with type 2 diabetes risk. A genetic risk score (GRS) for GSD was constructed with eight single nucleotide polymorphisms that were derived from the previous genome‐wide association studies. The causal associations of the score for GSD with type 2 diabetes were tested among 7,000 participants in Mendelian randomization analysis. We documented 1,110 incident type 2 diabetes cases during 73,895 person‐years of follow‐up from 2008 to 2013 (median 4.6 years). Compared with participants without GSD, the multivariate‐adjusted hazard ratio of type 2 diabetes risk in those with GSD was 1.22 (95% confidence interval CI, 1.03‐1.45, P = 0.02). Each 1 SD (0.23) increment in the weighted GRS was associated with a 17% increment of type 2 diabetes risk (odds ratio = 1.17, 95% CI, 0.90‐1.52) without statistical significance (P = 0.25). Conclusion: The present study supported a positive but not a causal association of GSD with type 2 diabetes risk. More studies are needed to verify our findings.
Essential metals play important roles in the carcinogenic process. However, seldom longitudinal investigations have evaluated their roles in lung cancer development. We aimed to investigate the ...associations between multiple essential metals and lung cancer incidence and to explore the potential mechanisms.
A nested case-control study of 440 incident lung cancer cases and 1:3 frequency matched 1320 healthy controls from the Dongfeng-Tongji Cohort was conducted. The baseline plasma concentrations of 11 essential metals (cobalt, copper, iron, manganese, molybdenum, rubidium, selenium, strontium, stannum, vanadium, and zinc) were measured, and their associations with lung cancer incidence were estimated. Effect of positive metal (zinc) on 4-year telomere attrition was then evaluated among an occupational cohort of 724 workers. We also assessed the transcriptional regulation effects of plasma zinc on mRNA expression profiles, and the expressions of zinc-related genes were further compared in pair-wised lung tumor and normal tissues.
Elevated plasma level of zinc was associated with lower incident risk of lung cancer OR (95% CI) = 0.89 (0.79, 0.99) and decreased 4-year telomere attrition β (95% CI) = −0.73 (−1.27, −0.19). These effects were pronounced among males. In particularly, zinc could regulate the expressions of 8 cancer-related genes, including SOD1, APE, TP53BP1, WDR33, LAPTM4B, TRIT1, HUWE1, and ZNF813, which were over-expressed in lung tumor tissues.
We propose that high plasma zinc could prevent incident lung cancer, probably by slowing down telomere attrition and regulating the expressions of cancer-related genes. These results provided a new insight into lung cancer prevention.
•Increased plasma zinc level was associated with a lower risk of lung cancer.•High plasma zinc level was associated with decreased telomere length attrition.•Plasma zinc level was associated with the expressions of 13 cancer-related genes.•8 of the 13 cancer-related genes were up-regulated in lung tumor tissues.
The aim of this study is to examine the bidirectional association between nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM).
The data was derived from the Dongfeng-Tongji ...cohort study, which was established in 2008 and followed until October 2013. NAFLD was classified as none, mild, moderate/severe based on ultrasound examination. The analysis to examine the association between NAFLD and incident T2DM risk included 18,111 participants free of diabetes at baseline and the duration of follow-up was 4.60 ± 0.60 years. Cox proportional regression model was used to calculate the hazard ratio (HR) for the association. The analysis to investigate the association between T2DM and incident NAFLD risk included 12,435 participants free of NAFLD at baseline. Logistic regression model was used to calculate the odd ratio (OR) of NAFLD.
Compared with those without NAFLD, individuals with mild or moderate/severe NAFLD had a monotonic elevated risk of developing T2DM (HR: 1.88 95% CI: 1.63-2.18 and 2.34 1.85-2.96, respectively) after adjustment for potential confounders. In a parallel analysis, compared to participants with fasting plasma glucose < 6.1 mmol/L, the ORs of developing NAFLD in subjects with impaired fasting glucose and T2DM were 1.35 (95% CI: 1.16-1.57) and 1.40 (95% CI: 1.22-1.62), respectively.
Our results provide compelling evidence that the NAFLD-T2DM association is bidirectional in Chinese population.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Visibility determination is a key requirement in a wide range of national and urban applications, such as national security, landscape management, and urban design. Mobile LiDAR point clouds can ...depict the urban built environment with a high level of details and accuracy. However, few three-dimensional visibility approaches have been developed for the street-level point-cloud data. Accordingly, an approach based on mobile LiDAR point clouds has been developed to map the three-dimensional visibility at the street level. The method consists of five steps: voxelization of point-cloud data, construction of lines-of-sight, construction of sectors of sight, construction of three-dimensional visible space, and calculation of volume index. The proposed approach is able to automatically measure the volume of visible space and openness at any viewpoint along a street. This approach has been applied to three study areas. The results indicated that the proposed approach enables accurate simulation of visible space as well as high-resolution (1 m × 1 m) mapping of the visible volume index. The proposed approach can make a contribution to the improvement of urban planning and design processes that aim at developing more sustainable built environments.
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