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The existing process for the preparation of cladded rebars is too complicated for large-scale industrial production. Therefore, this paper proposes a 55#/316L rebar preparation method based on vacuum hot rolling. The microstructure and mechanical properties of the composite interface of the rebar, along with the connecting technique, were studied using transmission electron microscopy, X-ray diffraction, and Vickers hardness testing. The obtained results showed that the minimum thickness of the 55#/316L rebar cladding was 0.25 mm, which was twice that of the M 329M/M 329-11 design standard used in the United States of America. Due to the diffusion of carbon, large numbers of second-phase particles were precipitated on the stainless-steel side, which resulted in intergranular chromium depletion. After multi-pass hot rolling, the minimum bonding strength of the composite interface reached 316.58 MPa, which was considerably higher than the specified value of 210 MPa. In addition, we designed three different types of rebar connection joints: sleeve, groove-welded, and bar-welded. According to the tensile test, the bar-welded joint had higher yield strength (385 MPa) and tensile strength (665 MPa) than the base rebar (376.6 MPa and 655 MPa), as well as a very high corrosion resistance. [ABSTRACT FROM AUTHOR]

Background Choline-related nutrients are dietary precursors of a gut microbial metabolite, trimethylamine-N-oxide, which has been linked to cardiometabolic diseases and related death. However, epidemiologic evidence on dietary choline and mortality remains limited, particularly among nonwhite populations. Objectives This study aimed to investigate the associations of choline-related nutrients with cardiometabolic and all-cause mortality among black and white Americans and Chinese adults. Methods Included were 49,858 blacks, 23,766 whites, and 134,001 Chinese, aged 40–79 y, who participated in 3 prospective cohorts and lived ≥1 y after enrollment. Cox regression models were used to estimate HRs and 95% CIs for cardiometabolic [e.g., ischemic heart disease (IHD), stroke, and diabetes] and all-cause deaths. To account for multiple testing, P values < 0.003 were considered significant. Results Mean choline intake among blacks, whites, and Chinese was 404.1 mg/d, 362.0 mg/d, and 296.8 mg/d, respectively. During a median follow-up of 11.7 y, 28,673 deaths were identified, including 11,141 cardiometabolic deaths. After comprehensive adjustments, including for overall diet quality and disease history, total choline intake was associated with increased cardiometabolic mortality among blacks and Chinese (HR for highest compared with lowest quintile: 1.26; 95% CI: 1.13, 1.40 and HR: 1.23; 95% CI: 1.11, 1.38, respectively; both P -trend < 0.001); among whites, the association was weaker (HR: 1.12; 95% CI: 0.95, 1.33; P -trend = 0.02). Total choline intake was also associated with diabetes and all-cause mortality in blacks (HR: 1.66; 95% CI: 1.26, 2.19 and HR: 1.20; 95% CI: 1.12, 1.29, respectively), with diabetes mortality in Chinese (HR: 2.24; 95% CI: 1.68, 2.97), and with IHD mortality in whites (HR: 1.31; 95% CI: 1.02, 1.69) (all P -trend < 0.001). The choline–mortality association was modified by alcohol consumption and appeared stronger among individuals with existing cardiometabolic disease. Betaine intake was associated with increased cardiometabolic mortality in Chinese only (HR: 1.16; 95% CI: 1.08, 1.25; P -trend < 0.001). Conclusions High choline intake was associated with increased cardiometabolic mortality in racially diverse populations. [ABSTRACT FROM AUTHOR]

Importance: Dietary fiber (the main source of prebiotics) and yogurt (a probiotic food) confer various health benefits via modulating the gut microbiota and metabolic pathways. However, their associations with lung cancer risk have not been well investigated., Objective: To evaluate the individual and joint associations of dietary fiber and yogurt consumption with lung cancer risk and to assess the potential effect modification of the associations by lifestyle and other dietary factors., Design, Setting, and Participants: This pooled analysis included 10 prospective cohorts involving 1 445 850 adults from studies that were conducted in the United States, Europe, and Asia. Data analyses were performed between November 2017 and February 2019. Using harmonized individual participant data, hazard ratios and 95% confidence intervals for lung cancer risk associated with dietary fiber and yogurt intakes were estimated for each cohort by Cox regression and pooled using random-effects meta-analysis. Participants who had a history of cancer at enrollment or developed any cancer, died, or were lost to follow-up within 2 years after enrollment were excluded., Exposures: Dietary fiber intake and yogurt consumption measured by validated instruments., Main Outcomes and Measures: Incident lung cancer, subclassified by histologic type (eg, adenocarcinoma, squamous cell carcinoma, and small cell carcinoma)., Results: The analytic sample included 627 988 men, with a mean (SD) age of 57.9 (9.0) years, and 817 862 women, with a mean (SD) age of 54.8 (9.7) years. During a median follow-up of 8.6 years, 18 822 incident lung cancer cases were documented. Both fiber and yogurt intakes were inversely associated with lung cancer risk after adjustment for status and pack-years of smoking and other lung cancer risk factors: hazard ratio, 0.83 (95% CI, 0.76-0.91) for the highest vs lowest quintile of fiber intake; and hazard ratio, 0.81 (95% CI, 0.76-0.87) for high vs no yogurt consumption. The fiber or yogurt associations with lung cancer were significant in never smokers and were consistently observed across sex, race/ethnicity, and tumor histologic type. When considered jointly, high yogurt consumption with the highest quintile of fiber intake showed more than 30% reduced risk of lung cancer than nonyogurt consumption with the lowest quintile of fiber intake (hazard ratio, 0.67 [95% CI, 0.61-0.73] in total study populations; hazard ratio, 0.69 [95% CI, 0.54-0.89] in never smokers), suggesting potential synergism., Conclusions and Relevance: Dietary fiber and yogurt consumption was associated with reduced risk of lung cancer after adjusting for known risk factors and among never smokers. Our findings suggest a potential protective role of prebiotics and probiotics against lung carcinogenesis.

Background: Previous genome-wide association studies (GWAS) have identified 42 loci (P < 5 × 10-8) associated with risk of colorectal cancer (CRC). Expanded consortium efforts facilitating the discovery of additional susceptibility loci may capture unexplained familial risk., Methods: We conducted a GWAS in European descent CRC cases and control subjects using a discovery-replication design, followed by examination of novel findings in a multiethnic sample (cumulative n = 163 315). In the discovery stage (36 948 case subjects/30 864 control subjects), we identified genetic variants with a minor allele frequency of 1% or greater associated with risk of CRC using logistic regression followed by a fixed-effects inverse variance weighted meta-analysis. All novel independent variants reaching genome-wide statistical significance (two-sided P < 5 × 10-8) were tested for replication in separate European ancestry samples (12 952 case subjects/48 383 control subjects). Next, we examined the generalizability of discovered variants in East Asians, African Americans, and Hispanics (12 085 case subjects/22 083 control subjects). Finally, we examined the contributions of novel risk variants to familial relative risk and examined the prediction capabilities of a polygenic risk score. All statistical tests were two-sided., Results: The discovery GWAS identified 11 variants associated with CRC at P < 5 × 10-8, of which nine (at 4q22.2/5p15.33/5p13.1/6p21.31/6p12.1/10q11.23/12q24.21/16q24.1/20q13.13) independently replicated at a P value of less than .05. Multiethnic follow-up supported the generalizability of discovery findings. These results demonstrated a 14.7% increase in familial relative risk explained by common risk alleles from 10.3% (95% confidence interval [CI] = 7.9% to 13.7%; known variants) to 11.9% (95% CI = 9.2% to 15.5%; known and novel variants). A polygenic risk score identified 4.3% of the population at an odds ratio for developing CRC of at least 2.0., Conclusions: This study provides insight into the architecture of common genetic variation contributing to CRC etiology and improves risk prediction for individualized screening., (© The Author(s) 2018. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Endometrial cancer (EC), a neoplasm of the uterine epithelial lining, is the most common gynecological malignancy in developed countries and the fourth most common cancer among US women. Women with a family history of EC have an increased risk for the disease, suggesting that inherited genetic factors play a role. We conducted a two-stage genome-wide association study of Type I EC. Stage 1 included 5,472 women (2,695 cases and 2,777 controls) of European ancestry from seven studies. We selected independent single-nucleotide polymorphisms (SNPs) that displayed the most significant associations with EC in Stage 1 for replication among 17,948 women (4,382 cases and 13,566 controls) in a multiethnic population (African America, Asian, Latina, Hawaiian and European ancestry), from nine studies. Although no novel variants reached genome-wide significance, we replicated previously identified associations with genetic markers near the HNF1B locus. Our findings suggest that larger studies with specific tumor classification are necessary to identify novel genetic polymorphisms associated with EC susceptibility.

Childbearing at an older age has been associated with a lower risk of endometrial cancer, but whether the association is independent of the number of births or other factors remains unclear. Individual-level data from 4 cohort and 13 case-control studies in the Epidemiology of Endometrial Cancer Consortium were pooled. A total of 8,671 cases of endometrial cancer and 16,562 controls were included in the analysis. After adjustment for known risk factors, endometrial cancer risk declined with increasing age at last birth (P(trend) < 0.0001). The pooled odds ratio per 5-year increase in age at last birth was 0.87 (95% confidence interval: 0.85, 0.90). Women who last gave birth at 40 years of age or older had a 44% decreased risk compared with women who had their last birth under the age of 25 years (95% confidence interval: 47, 66). The protective association was similar across the different age-at-diagnosis groups and for the 2 major tumor histologic subtypes (type I and type II). No effect modification was observed by body mass index, parity, or exogenous hormone use. In this large pooled analysis, late age at last birth was independently associated with a reduced risk of endometrial cancer, and the reduced risk persisted for many years.

Many in-vitro and animal studies have provided evidence that tea has many possible anticarcinogenic mechanisms, but epidemiological evidence for the effect of tea consumption on the primary liver cancer risk remains controversial and, to date, there have been no quantitative meta-analyses reported regarding this topic. The aim of this meta-analysis is to evaluate the association between tea consumption and the risk of primary liver cancer from case-control and cohort studies. Epidemiological studies of tea consumption in relation to primary liver cancer were identified by searching MEDLINE, EMBASE, Chinese Bio-medicine Database, and Chinese Wanfang Database, from January 1979 to December 2009. The language of publication was restricted to English and Chinese. Heterogeneity and publication bias were evaluated and the pooled relative risks (RRs) were calculated using a fixed-effect model. A random-effect model was used when statistically significant heterogeneity existed. All data analyses were carried out using R software and the package 'meta'. A total of 13 epidemiological studies consisting of six case-control and seven prospective cohort studies were included. An inverse association with a borderline significance [RR = 0.77; 95% confidence interval (CI) = 0.57-1.03] was found between tea consumption and primary liver cancer. The studies with higher quality showed a similar finding with pooled RR of 0.79 (95% CI = 0.61-1.01). Both men (RR = 0.86; 95% CI = 0.77-0.95) and women (RR = 0.54; 95% CI = 0.37-0.79) showed the preventive effects of tea intake on the development of primary liver cancer. Eight studies conducted on green tea consumption suggested that it was associated with a moderate reduction in risk for primary liver cancer (RR = 0.79; 95% CI = 0.68-0.93). No publication bias was found either from funnel plot visualization or the Egger-weighted regression (P value = 0.34) and the Begg rank correlation (P value = 0.12) methods. These results provide more evidence for a protective effect of tea consumption against the development of primary liver cancer. More well-conducted and large-scale epidemiological studies are needed.

Background: Incidence of breast cancer is rising in Asian countries, and breast cancer is the most common cancer among Asian women. However, there are few recent descriptive reports on the epidemiology of breast cancer among Eastern and Southeastern Asian populations., Methods: We examined incidence trends for invasive breast cancer in women aged ≥20 years from 15 registries in Eastern (China, Japan, the Republic of Korea, Taiwan) and Southeastern Asia (the Philippines, Singapore, Thailand) for the period 1993-2002 mainly using data from Cancer Incidence in Five Continents, Volumes VIII and IX. We compared trends in annual incidence rates and age-specific incidence curves over a 10-year period. We also compared the incidence rates of Asian-Americans with the rates of their Asian counterparts., Results: Breast cancer incidence rates increased gradually over time in all study populations. Rates were relatively high in Southeastern Asia and became progressively lower along a south-to-north gradient, with a fourfold geographic variation within the study populations. Age-specific incidence curves showed patterns that gradually changed according to incidence rates. Breast cancer incidence among Asian women living in the United States was 1.5-4 times higher than the corresponding incidence rate in the women's respective countries of origin., Conclusion: Breast cancer incidence is expected to continue to increase for the next 10 years in Asia and may approach rates reported among Asian-Americans. The number and mean age of breast cancer cases is expected to increase as the female Asian population ages, the prevalence of certain risk factors changes (early menarche, late menopause, low parity, late age at first live birth, and low prevalence of breastfeeding), and as Asian countries introduce mass screening programs.

The Cohort Consortium Vitamin D Pooling Project of Rarer Cancers (VDPP), a consortium of 10 prospective cohort studies from the United States, Finland, and China, was formed to examine the associations between circulating 25-hydroxyvitamin D (25(OH)D) concentrations and the risk of rarer cancers. Cases (total n = 5,491) included incident primary endometrial (n = 830), kidney (n = 775), ovarian (n = 516), pancreatic (n = 952), and upper gastrointestinal tract (n = 1,065) cancers and non-Hodgkin lymphoma (n = 1,353) diagnosed in the participating cohorts. At least 1 control was matched to each case on age, date of blood collection (1974-2006), sex, and race/ethnicity (n = 6,714). Covariate data were obtained from each cohort in a standardized manner. The majority of the serum or plasma samples were assayed in a central laboratory using a direct, competitive chemiluminescence immunoassay on the DiaSorin LIAISON platform (DiaSorin, Inc., Stillwater, Minnesota). Masked quality control samples included serum standards from the US National Institute of Standards and Technology. Conditional logistic regression analyses were conducted using clinically defined cutpoints, with 50-<75 nmol/L as the reference category. Meta-analyses were also conducted using inverse-variance weights in random-effects models. This consortium approach permits estimation of the association between 25(OH)D and several rarer cancers with high accuracy and precision across a wide range of 25(OH)D concentrations.

Upper gastrointestinal (GI) cancers of the stomach and esophagus have high incidence and mortality worldwide, but they are uncommon in Western countries. Little information exists on the association between vitamin D and risk of upper GI cancers. This study examined the association between circulating 25-hydroxyvitamin D (25(OH)D) and upper GI cancer risk in the Cohort Consortium Vitamin D Pooling Project of Rarer Cancers. Concentrations of 25(OH)D were measured from 1,065 upper GI cancer cases and 1,066 age-, sex-, race-, and season-of blood draw-matched controls from 8 prospective cohort studies. In multivariate-adjusted models, circulating 25(OH)D concentration was not significantly associated with upper GI cancer risk. Subgroup analysis by race showed that among Asians, but not Caucasians, lower concentrations of 25(OH)D (<25 nmol/L) were associated with a statistically significant decreased risk of upper GI cancer (reference: 50-<75 nmol/L) (odds ratio = 0.53, 95% confidence interval: 0.31, 0.91; P trend = 0.003). Never smokers with concentrations of <25 nmol/L showed a lower risk of upper GI cancers (odds ratio = 0.55, 95% confidence interval: 0.31, 0.96). Subgroup analyses by alcohol consumption produced opposing trends. Results do not support the hypothesis that interventions aimed at increasing vitamin D status would lead to a lower risk of these highly fatal cancers.

Case-control studies generally suggesting an inverse association between sun exposure and non-Hodgkin lymphoma (NHL) have led to speculation that vitamin D may protect against lymphomagenesis. To examine this hypothesis, the authors conducted a pooled investigation of circulating 25-hydroxyvitamin D (25(OH)D) and subsequent NHL risk within 10 cohorts participating in the Cohort Consortium Vitamin D Pooling Project of Rarer Cancers. The authors analyzed measurements from 1,353 cases and 1,778 controls using conditional logistic regression and other methods to estimate the association of 25(OH)D with NHL. No clear evidence of association between categories of 25(OH)D concentration and NHL was observed overall (P(trend) = 0.68) or by sex (men, P(trend) = 0.50; women, P(trend) = 0.16). Findings for other measures (continuous log(25(OH)D), categories of 25(OH)D using sex-/cohort-/season-specific quartiles as cutpoints, categories of season-adjusted residuals of predicted 25(OH)D using quartiles as cutpoints) were generally null, although some measures of increasing 25(OH)D were suggestive of an increased risk for women. Results from stratified analyses and investigations of histologic subtypes of NHL were also null. These findings do not support the hypothesis that elevated circulating 25(OH)D concentration is associated with a reduced risk of NHL. Future research investigating the biologic basis for the sunlight-NHL association should consider alternative mechanisms, such as immunologic effects.

Although the kidney is a major organ for vitamin D metabolism, activity, and calcium-related homeostasis, little is known about whether this nutrient plays a role in the development or the inhibition of kidney cancer. To address this gap in knowledge, the authors examined the association between circulating 25-hydroxyvitamin D (25(OH)D) and kidney cancer within a large, nested case-control study developed as part of the Cohort Consortium Vitamin D Pooling Project of Rarer Cancers. Concentrations of 25(OH)D were measured from 775 kidney cancer cases and 775 age-, sex-, race-, and season-matched controls from 8 prospective cohort studies. Overall, neither low nor high concentrations of circulating 25(OH)D were significantly associated with kidney cancer risk. Although the data showed a statistically significant decreased risk for females (odds ratio = 0.31, 95% confidence interval: 0.12, 0.85) with 25(OH)D concentrations of > or =75 nmol/L, the linear trend was not statistically significant and the number of cases in this category was small (n = 14). The findings from this consortium-based study do not support the hypothesis that vitamin D is inversely associated with the risk of kidney cancer overall or with renal cell carcinoma specifically.