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In the process of service, reinforced concrete structures have to bear both load and multi-environmental factors. The deterioration of reinforced concrete beams is critical to the durability, safety, and sustainability of reinforced concrete structures. The main aim of the present research is to determine the degradation mechanism of reinforced concrete beams subjected to sustained loading and multi-environmental factors. Reinforced concrete beam specimens were prepared, loaded and then exerted multi-environmental factors. At the end of each degradation period, the degradation of concrete (chemical contents of concrete beam surfaces, carbonation depth, compressive strength and maximum cracks) and the corrosion of steel bars (corrosion ratio and tensile strength) were continuously measured. Moreover, degraded reinforced concrete beams were flexural loaded in four-point bending failure tests. The degradation mechanism of reinforced concrete beams subjected to sustained loading and multi-environmental factors was analyzed. Thus, this study can promote a comprehensive understanding of reinforced concrete beams subjected to sustained loading and multi-environmental factors. [ABSTRACT FROM AUTHOR]

Background Some hormones measured in pregnancy are linked to certain hormone-sensitive cancers. We investigated whether routine serum screening in pregnancy is associated with a woman's subsequent risk of hormone-sensitive cancer. Methods This population-based cohort study included women aged 12–55 years who underwent prenatal screening between 11 weeks + 0 days of gestation to 20 weeks + 6 days of gestation in Ontario, Canada, 1993–2011, where universal health care is available. The hazard ratio of newly diagnosed breast, ovarian, endometrial, and thyroid cancer—arising at 21 weeks + 0 days of gestation or thereafter—was estimated in association with an abnormally low (≤5th) or high (>95th) percentile multiple of the median (MoM) for alpha-fetoprotein (AFP), total human chorionic gonadotropin (hCG), unconjugated estriol, pregnancy-associated plasma protein A, and dimeric inhibin A. Results Among 677 247 pregnant women followed for a median of 11.0 years (interquartile range = 7.5–16.1), 7231 (1.07%) developed breast cancer, 515 (0.08%) ovarian cancer, 508 (0.08%) endometrial cancer, and 4105 (0.61%) thyroid cancer. In multivariable adjusted models, abnormally high hCG greater than the 95th percentile MoM was associated with a doubling in the risk of endometrial cancer (adjusted hazard ratio [aHR] = 1.98, 95% confidence interval [CI] = 1.33 to 2.95), and abnormally low AFP at the fifth percentile or less MoM conferred a moderately greater risk of thyroid cancer (aHR = 1.21, 95% CI = 1.07 to 1.38). Abnormally low pregnancy-associated plasma protein A at the fifth percentile or less MoM was not statistically significantly associated with breast cancer after multivariable adjustment (aHR = 1.19, 95% CI = 0.98 to 1.36). Conclusions Women with abnormally high levels of serum hCG or low AFP in early pregnancy may be at a greater future risk of certain types of hormone-sensitive cancers. [ABSTRACT FROM AUTHOR]

Objective: To predict birth weight at various potential gestational ages of delivery based on data routinely available at the first antenatal visit., Design: Individual participant data meta-analysis., Data Sources: Individual participant data of four cohorts (237 228 pregnancies) from the International Prediction of Pregnancy Complications (IPPIC) network dataset., Eligibility Criteria for Selecting Studies: Studies in the IPPIC network were identified by searching major databases for studies reporting risk factors for adverse pregnancy outcomes, such as pre-eclampsia, fetal growth restriction, and stillbirth, from database inception to August 2019. Data of four IPPIC cohorts (237 228 pregnancies) from the US (National Institute of Child Health and Human Development, 2018; 233 483 pregnancies), UK (Allen et al, 2017; 1045 pregnancies), Norway (STORK Groruddalen research programme, 2010; 823 pregnancies), and Australia (Rumbold et al, 2006; 1877 pregnancies) were included in the development of the model., Results: The IPPIC birth weight model was developed with random intercept regression models with backward elimination for variable selection. Internal-external cross validation was performed to assess the study specific and pooled performance of the model, reported as calibration slope, calibration-in-the-large, and observed versus expected average birth weight ratio. Meta-analysis showed that the apparent performance of the model had good calibration (calibration slope 0.99, 95% confidence interval (CI) 0.88 to 1.10; calibration-in-the-large 44.5 g, -18.4 to 107.3) with an observed versus expected average birth weight ratio of 1.02 (95% CI 0.97 to 1.07). The proportion of variation in birth weight explained by the model (R 2 ) was 46.9% (range 32.7-56.1% in each cohort). On internal-external cross validation, the model showed good calibration and predictive performance when validated in three cohorts with a calibration slope of 0.90 (Allen cohort), 1.04 (STORK Groruddalen cohort), and 1.07 (Rumbold cohort), calibration-in-the-large of -22.3 g (Allen cohort), -33.42 (Rumbold cohort), and 86.4 g (STORK Groruddalen cohort), and observed versus expected ratio of 0.99 (Rumbold cohort), 1.00 (Allen cohort), and 1.03 (STORK Groruddalen cohort); respective pooled estimates were 1.00 (95% CI 0.78 to 1.23; calibration slope), 9.7 g (-154.3 to 173.8; calibration-in-the-large), and 1.00 (0.94 to 1.07; observed v expected ratio). The model predictions were more accurate (smaller mean square error) in the lower end of predicted birth weight, which is important in informing clinical decision making., Conclusions: The IPPIC birth weight model allowed birth weight predictions for a range of possible gestational ages. The model explained about 50% of individual variation in birth weights, was well calibrated (especially in babies at high risk of fetal growth restriction and its complications), and showed promising performance in four different populations included in the individual participant data meta-analysis. Further research to examine the generalisability of performance in other countries, settings, and subgroups is required., Trial Registration: PROSPERO CRD42019135045., Competing Interests: All authors have completed the ICMJE uniform disclosure form at www.icmje.org/disclosure-of-interest/ and declare: support from the National Institute for Health and Care Research Health Technology Assessment UK programme for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work., (Copyright © Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: To investigate the prevalence of myopia among children and adolescents in a local area (Liyang City) of China and analyze the influencing factors, so as to formulate corresponding preventive measures., Methods: A questionnaire survey was conducted, mainly investigating subjects' age, gender, residence (urban/rural areas), parental myopia, daily time spent outdoors, daily sleep time, distance between computer screen and eyes, less than one punch (10 cm) from the chest to the edge of the desk when reading and writing, one inch (3 cm) between finger and pen tip when writing, number of in-school physical education (PE) classes, length of TV watching, and size of TV. The myopia of all participants was recorded., Results: This study enrolled 7,948 children and adolescents, including 4,733 (59.55%) cases of myopia, 1,025 (12.90%) of astigmatism, 251 (3.16%) of hyperopia, and 699 (8.79%) of anisometropia respectively. There were 2,519 (53.22%) cases of myopia in the left eye and 2,214 (46.78%) in the right eye. Low, moderate, and high myopia were determined in 2,682 (56.67%), 1,583 (33.45%), and 468 (9.89%), respectively. In terms of spherical equivalent (SEQ), a statistically lower SEQ was observed in urban areas (-1.56±0.46 d) versus suburban counties (-1.17±0.33 d), and in females (-1.68±0.30 d) compared with males (-1.17±0.44 d). The mean SEQ gradually decreased with age. The prevalence of myopia was 63.84% (2,436/3,816) in females, statistically higher than that of 55.59% (2,197/4,132) in males (χ 2 =56.00, P < 0.0001). The incidence of myopia was statistically higher in urban areas (67.93% [3,321/4,889]) versus rural areas (46.16% [1,412/3,059]). Parental myopia, one inch between finger and pen tip when writing, daily time spent outdoors, daily sleep time, distance between computer screen and eyes, less than one punch from the chest to the edge of the desk when reading and writing, number of in-school PE classes, and daily length of TV watching were significantly correlated with the occurrence of myopia., Conclusions: Parents are advised to pay attention to daily time spent outdoors, sleep time, distance between the computer screen and the eyes, distance between the chest and the edge of the table when reading and writing, and length of TV watching of their children. As far as schools are concerned, PE activity time should be properly maintained to ensure that children have enough outdoor exercise time to reduce eye fatigue., Competing Interests: None., (AJTR Copyright © 2022.)

Background: It is recommended that all pregnant women be offered screening for Down syndrome and open neural tube defects, but emerging prenatal tests that are not publicly insured may compromise access. We evaluated screening rates for publicly insured screening tests across health care regions in the province of Ontario and determined whether maternal, provider or regional characteristics are associated with screening uptake., Methods: We conducted a population-based retrospective cohort study involving pregnant women in Ontario who were at or beyond 16 weeks' gestation in 2007-2009. We ascertained prenatal screening rates using linked health administrative and prenatal screening datasets. We examined maternal, provider and regional characteristics associated with screening uptake. Rate ratios (RRs) were estimated., Results: Of the 264 737 women included in the study, 62.2% received prenatal screening; uptake varied considerably by region (range 27.8%-80.3%). A greater proportion of women initiated screening in the first rather than the second trimester (50.0% v. 12.2%). Factors associated with lower screening rates included living in a rural area versus an urban area (adjusted rate ratio 0.64, 95% confidence interval [CI] 0.63-0.66), receiving first-trimester care from a family physician or midwife versus an obstetrician (adjusted rate ratio 0.91, 95% CI 0.90-0.92, and 0.40, 95% CI 0.38-0.43, respectively) and being in a lower income quintile (adjusted RR for lowest v. highest 0.95, 95% CI 0.94-0.96). Being an immigrant or a refugee was associated with higher screening rates., Interpretation: There were significant maternal, provider and regional differences in the uptake of prenatal screening across the province. With discrepancies expected to increase with the emergence of noninvasive prenatal tests paid for out of pocket by many women, policy efforts to reduce barriers to prenatal screening and optimize its availability are warranted.

Dedifferentiated chondrosarcoma (CS) is a rare, highly malignant variant of CS in which a high-grade sarcoma coexists with a low-grade chondroid tumor. In this study, a novel dedifferentiated CS cell line, MS0812, was spontaneously established from mutated human embryonic muscle cells. Several features of the cell line were investigated, including growth characteristics, cytogenetics, electron microscopic features, expression of various antigenic markers and tumor formation. MS0812 has been cultured continuously for more than 3 years. The growth characteristics of MS0812 are similar to the immortalized cell lines as reported. The cell line exhibited complex karyotypes and hyperploidy, the chromosome number ranged from 50 to 158. MS0812 was positive for vimentin, desmin and muscle actin, indicating their muscle origin. With specific inductive condition, MS0812 differentiates into neural cells and adipocytes. Deletion of the p16 gene, which seemed to play a major role in the malignant phenotype of this cell line, was confirmed by PCR and immunocytochemistry. MS0812 formed tumors in nude mice, and the tumor revealed a fibrosarcoma with chondroid components, which were consistent with dedifferentiated CS as reported. Chondroid components showed metachromasia by Alcian blue and toluidine blue and were S100 and collagen-II positive. To our knowledge, this is the first report of the establishment of a human dedifferentiated chondrosarcoma from mutated human embryonic muscle cells, and it is a useful model for the study of the molecular pathogenesis of dedifferentiated CS.