Interface thermal conductivities induced by van der Waals interactions.

The interface heat transfer of two layers induced by van der Waals (vdW) contacts is theoretically investigated, based on first-principles calculations at low temperatures. The results suggest that out-of-plane acoustic phonons with low frequencies dominate the interface thermal transport due to the vdW interaction. The interface thermal conductivity is proportional to the cubic of temperature at very low temperatures, but becomes linearly proportional to temperature as temperature increases. We show that manipulating the strain alters vdW coupling, leading to increased interfacial thermal conductivity at the interface. Our findings provide valuable insights into the interface heat transport in vdW heterostructures and support further design and optimization of electronic and optoelectronic nanodevices based on vdW contacts.

[Analysis of risk factors for venous thromboembolism in patients with polycythemia vera and establishment of a prediction model].

Objective: To investigate the risk factors of venous thrombosis in patients with polycythemia vera (PV) and establish a prediction model for venous thrombosis. Methods: PV patients with JAK2V617F gene mutation positive in the Second Hospital of Tianjin Medical University from September 2017 to November 2023 were retrospectively included. The patients were divided into groups according to whether they had venous thrombosis. After matching age and gender factors with propensity scores, 102 patients were included in the venous thrombosis group [46 males, 56 females, with a median age M (Q1, Q3) of 52 (44, 60) years] and 204 cases were included in the group without venous thrombosis [92 males, 112 females, with a median age of 52 (44, 59) years]. The clinical and laboratory characteristics, disease progression and incidence of gene mutation were compared between the two groups. The follow-up cohort ended on November 20, 2023, with a median follow-up [M (Q1, Q3)] of 11 (1, 53) years. Multivariate Cox risk model was used to analyze the influencing factors of venous thrombosis in PV patients, and establish a scoring system for the venous thrombosis risk factor prediction model of PV patients. Receiver operating characteristic (ROC) curve was used to evaluate the predictive efficiency of the model. Results: Hemoglobin concentration, the ratio of hematopoietic volume≥55%, neutrophil to lymphocyte ratio≥5, hypertension, subcostal spleen≥5 cm and secondary myelofibrosis in venous thrombosis group were higher than those in non-venous thrombosis group (all P<0.05). In addition, the proportion of history of thromboembolism, V617F gene mutation load (V617F%)≥50%, diabetes mellitus, ASXL1 mutation and secondary reticular silver staining≥3 in the venous thrombosis group were higher than those in the non-venous thrombosis group (all P<0.05). The proportion of PV patients with 3 or more gene mutations was 44.1% (45/102) in venous thrombosis group, which was higher than that of PV patients without venous thrombosis 29.9% (61/204) (P=0.014). The proportion of ASXL1 gene mutation in venous thrombosis group was 17.6% (18/102), which was higher than the 4.9% (10/204) in non-venous thrombosis group (P<0.001). Multivariate Cox risk model analysis showed that previous thromboembolism history (HR=2.031, 95%CI: 1.297-3.179, P=0.002), V617F%≥50% (HR=2.141, 95%CI: 1.370-3.347, P=0.001), ASXL1 mutation (HR=4.632, 95%CI: 1.497-14.336, P=0.008), spleen subcostal≥5 cm (HR=1.771, 95%CI: 1.047-2.996, P=0.033) are the risk factors of venous thrombosis in PV patients. According to HR values, a score system for predicting risk of venous thrombosis in PV patients was established: previous history of thromboembolism, V617F%≥50% and spleen subcostoal≥5 cm were assigned 1 point respectively, and ASXL1 mutation was assigned 2 points. Low risk group: score 0, medium risk group: score 1-2, high risk group: score≥3. The ROC curve analysis of the model for predicting venous thrombosis in PV patients showed that the area under the curve (AUC) was 0.807 (95%CI: 0.755-0.860), with the sensitivity of 88.2% and the specificity of 59.8% when the Youden index was 0.48. Conclusions: Previous thromboembolism history, V617F%≥50%, ASXL1 mutation, spleen subcostoal≥5 cm are risk factors of venous thrombosis in PV patients. The established prediction model has good prediction efficiency.

[Effects of parity on nutrition and health status of Chinese women of childbearing age].

Objective: To analyze effects of parity on women's nutrition and health status. Methods: This study was based on the data bank of "Chinese Nutrition and Health Surveillance of Children and Adolescents Aged 0-17 years old and Lactating Mothers from 2016 to 2017". Using a multi-stage stratified random sampling method, 17 771 women at 0 to 24 months postpartum from 31 provinces in Mainland China were included in this study. Questionnaires were used to collect data on women's general demographic characteristics, parity, mode of delivery, pre-pregnancy weight, pre-delivery weight, diseases before and during pregnancy, postpartum hemorrhage. Current body height, body weight, waist circumference, and blood pressure were measured. Blood hemoglobin, blood glucose and blood lipids were detected. Pre-pregnancy BMI, gestational weight gain, postpartum weight retention, postpartum BMI, the rates of anemia, hypertension, diabetes, and dyslipidemia were calculated. Survey sample weights were calculated according to the sampling design and number of children under 2 years old from the sixth population census data of China. Effects of parity on the observational indicators after adjusting for confounding factors were analyzed by multivariate linear regression and multivariate logistic regression. Results: The age of 17 771 women was (29.5±5.0) years old, 12.2% (2 172) were over 35 but less than 40 years old, and 3.2% (563) were over 40 years old; the women with one parity, two parities, and three parities accounted for 47.3% (8 413), 48.5% (8 620) and 4.2% (738), respectively; urban women accounted for 49.9% (8 875), and rural women accounted for 50.1% (8 896). The results from multivariate linear regression showed that the pre-pregnancy BMI of women with two and three parities was 0.55 kg/m2 and 0.76 kg/m2 higher than women with one parity, respectively; the results of multivariate logistic regression showed that the OR(95%CI) of pre-pregnancy anemia was 1.45(1.04-2.02) for women with three parities compared with women with one parity, and the OR(95%CI) of anemia during pregnancy for women with two parities was 1.20(1.06-1.35) compared with women with one parity. Conclusion: Parity is associated with pre-pregnancy BMI and risk of anemia before and during pregnancy in women of reproductive age.

Substrate dependent terahertz magneto-optical properties of monolayer WS2.

Terahertz (THz) magneto-optical (MO) properties of monolayer (ML) tungsten disulfide (WS2), placed on different substrates and subjected to external magnetic fields, are studied using THz time-domain spectroscopy (TDS). We find that the THz MO conductivity exhibits a nearly linear response in a weak magnetic field, while a distinctly nonlinear/oscillating behavior is found in strong magnetic fields owing to strong substrate-induced random impurity scattering and interactions. The THz MO response of ML WS2 depends sensitively on the choice of the substrates, which we trace back to electronic localization and the impact of the substrates on the Landau level (LL) spectrum. Our results provide an in-depth understanding of the THz MO properties of ML WS2/substrate systems, especially the effect of substrates, which can be utilized to realize atomically thin THz MO nano-devices.

Optical properties of surface states in two-dimensional topological insulators.

We present a simple and tractable approach to investigate the optical properties of surface states in two-dimensional (2D) topological insulators (TIs). The analytic expression of optical conductivity of surface states in 2D TIs are obtained based on the kinetic equations. It is found that universal optical conductance can be observed in the high frequency region, which does not depend on the temperature, the chemical potential, or the bandgap of the systems. This universal optical conductance is similar to that in graphene. However, the optical absorption edge of such surface states strongly depend on the chemical potential and the bandgap of the systems. There are obvious optical absorption peaks at low temperature in the low frequency region, which are very different from that in graphene. The bandgaps in surface states can be accurately experimentally measured by the optical absorption edges or the peaks. We expect that our theoretical results offer transparent understandings for the experimental results and applications of 2D TIs.

[Prevalence of calf muscle cramps and influencing factors for pregnant women in China during 2010-2012].

Objective: To investigate the prevalence of calf muscle cramps and possible influencing factors for pregnant women in China. Methods: Using a multi-stage stratified probability proportional to size cluster randomization sampling method during 2010-2012. A total of 3 582 pregnant women were investigated at 150 counties from 31 provinces in China mainland. Information on calf muscle cramps, demographic socio-economic status, pregnancy information, and the physical activities was collected through questionnaires. The semi-quantitative food frequency questionnaire (FFQ) was used to collect food intake of pregnant women. Dynamic cluster analysis was used to assess dietary pattern. Multiple logistic regression was used to investigate the possible influencing factors for calf muscle cramps. Results: The prevalence of calf muscle cramps was 32.9% (1 180/3 582) in Chinese pregnant women, which was 11.6% (87/748), 28.2% (420/1 492), and 50.2% (673/1 342), respectively, during the first, second and third trimester. There were significant differences between them (χ(2)=349.16, P<0.001). Dietary patterns of the pregnant women were classified into three groups, which called relatively balanced pattern, high vegetables and fruits pattern, and high dairy pattern. Among the three groups, the prevalence of calf muscle cramps was 32.0% (952/2 971), 37.2% (186/500), and 37.8% (42/111), with significant differences (χ(2)=6.39, P=0.041). The OR (95%CI) values of calf muscle cramps in the second and third trimester was 2.96 (2.28-3.83), and 8.02 (6.16-10.44), respectively, comparing with the first trimester. The OR (95%CI) values of calf muscle cramps in the women taking calcium before pregnant was 1.45 (1.19-1.76), comparing with the one who was not taken. The OR (95%CI) values of calf muscle cramps in the women who had been diagnosed by pregnancy-induced hypertension was 5.76 (2.06-16.12), comparing with the one who had not been diagnosed. The OR (95%CI) values of calf muscle cramps in the high vegetables and fruits pattern and high dairy pattern was 1.13 (0.91-1.41), and 1.18 (0.76-1.81), respectively, comparing with the relatively balanced pattern. Conclusion: The prevalence of calf muscle cramps was relatively high in Chinese pregnant women, which was significantly different among three trimesters. The residential areas, occupation, and pregnancy-induced hypertension might be related to the prevalence of calf muscle cramps. However, there was no significant difference among different dietary patterns.

[Gestational weight gain and optimal ranges in Chinese mothers giving singleton and full-term births in 2013].

Objective: To analyze the status of gestational weight gain (GWG) among Chinese mothers who gave singleton and full-term births, and to look at optimal GWG ranges. Methods: In 2013, using the multi-stage stratified and population proportional cluster sampling method, we investigated 8 323 mother-child pairs at their 0-24 months postpartum from 55 counties (cities/districts) of 30 provinces (except Tibet) in mainland China. Questionnaire was used to collect data on body weight before pregnancy and delivery, diseases during gestation, hemorrhage or not at postpartum, child birth weight and length, and other information about pregnant outcomes. We measured mother's body weight and height, and child's body weight and length. Based on 'Chinese Adult Body Weight Standard', we divided mothers into four groups according to their body weight before pregnancy: low weight (BMI<18.5 kg/m(2)), normal weight (BMI 18.5-23.9 kg/m(2)), overweight (BMI 24.0-27.9 kg/m(2)) and obesity (BMI≥28.0 kg/m(2)). The status of GWG was assessed by IOM optimal GWG guidelines. Chinese optimal GWG ranges were calculated according to the association of GWG with pregnant outcomes and anthropometry of mothers and children, and according to P25-P75 of GWG among mothers who had good pregnant outcomes and good anthropometry, and whose children had good anthropometry. The status of GWG was assessed by the new optimal ranges. Results: P50 (P25-P75) of GWG among the 8 323 mothers was 15.0 (10.0-19.0) kg. According to the proposed optimal GWG ranges of IOM, the proportions of inadequate, optimal and excessive GWG accounted for 27.2% (2 263 mothers), 36.2% (3 016 mothers) and 36.6% (3 044 mothers). The optimal GWG ranges for low weight, normal weight, overweight and obesity were 11.5-18.0, 10.0-15.0, 8.0-14.0 and 5.0-11.5 kg. Based on these optimal GWG ranges established in this study, the rates of inadequate, optimal and excessive GWG were 15.7% (1 303 mothers), 45.0% (3 744 mothers) and 39.3% (3 276 mothers), and these rates were significantly different from that defined by the IOM standards (χ2=345.36, P<0.001). Conclusion: The median of GWG among Chinese mothers is 15.0 kg, which is at a relatively higher level. This study suggests the optimal GWG ranges for Chinese women who give singleton and full-term babies, which appears lower than IOM's.

[The influencing factors of anemia for pregnant women between 2010-2012 in China].

Objective: To investigate the prevalence of anemia and related risk factors for pregnant women in China. Method: Based on Chinese National Nutrition and Health Surveillance 2010-2012, a total of 3 501 pregnant women were investigated from 150 counties of 31 provinces, municipalities and autonomous regions in China, using a multi-stage stratified cluster randomization sampling method. General information of pregnant women, health status, and food intake during the gestation, was collected through a questionnaire investigation. 6 ml fasting venous blood was collected for the determination of hemoglobin concentration. Data were analyzed using multiple logistic regression to investigate the prevalence of anemia and the related influencing factors. Results: The 605 of 3 501 pregnant women had anemia. The prevalence of anemia was 17.2%; and mild anemia accounted for about 61.0% (369/605). Compared with the pregnant women living in the large cities, the OR (95%CI) of those living in the poor rural areas was 1.46 (1.08-1.98). Compared with the pregnant women living in the south area of China, the OR (95%CI) of those living in the north area of China was 1.39 (1.15-1.68); Compared with the pregnant women in the first trimester, the OR (95%CI) of those in the second trimester and the third trimester were 1.79 (1.33-2.43) and 2.11 (1.56-2.85), respectively. The OR (95%CI) of pregnant women who had used folic acid supplementation within the 6 months prior to gestation was 0.76 (0.63-0.93) compared with those who had not used. Conclusion: From 2010 to 2012, the epidemic characteristics of anemia was mild for the pregnant women in China, and pregnant women residential areas, periods of pregnancy and whether to take folic acid were related to anemia.

[Status and related factors for gestational weight gain of Chinese pregnant women during 2010-2012].

Objective: To examine the status and related factors for gestational weight gain of Chinese pregnant women at different trimesters in 2010-2012. Methods: Participants were from Chinese National Nutrition and Health Surveillance in 2010-2012. Using a multi-stage stratified cluster random sampling method, we recruited 2 805 singleton pregnant women with gestational age 13 weeks or more from 31 provinces of China. A standard questionnaire was used to collect general information and pre-pregnancy weight; body weight and height of pregnant women were measured using a unified weighing scale and stadiometer, dietary intake during the previous year was collected using a food frequency questionnaire. A multiple logistic regression was used to analyze potential factors associated with appropriate gestational weight gain. Results: Among 2 805 pregnant women, 1 441 were in the second (13-27 weeks) and 1 364 in the third trimesters (≥28 weeks) . In the 2(nd) trimester, 229 cases (15.9%), 440 cases (30.5%) and 772 cases (53.6%) were insufficient gestational weight gain, appropriate gestational weight gain and excessive gestational weight gain respectively. So were 256 cases (18.8%), 474 cases (34.8%), 634 cases (46.5%) in the 3(rd) trimester respectively. In the multivariate unconditional logistic model, less fruit intake was associated with insufficient weight gain for women in the 2(nd) trimester (OR (95%CI): 1.58 (1.06-2.34)). Pregnant women with Han ethnicity who live in the small/medium city had lower risk of insufficient weight gain in the 3(rd) trimester (OR (95%CI): 0.58 (0.34-0.98)). Those pregnant women with physical activity <1 hour/day had a higher risk of excessive weight gain (OR (95%CI): 1.33 (1.02-1.73)). Conclusion: The prevalence of appropriate gestational weight gain was low in China. Our study suggests that pregnant weight gain is associated with fruit intake, types of residential area and physical activity.

[Preoperative C-reactive protein/albumin ratio predicts the prognosis of patients with resectable pancreatic cancer].

Objective: To evaluate the clinical significance of C-reactive protein/albumin ratio in predicting the postoperative prognosis of pancreatic cancer patients. Methods: The clinical date of 97 patients with resectable pancreatic cancers who treated at Department of Hepatobiliary and Pancreatic Surgery, the third Affiliated Hospital of Soochow University from January 2005 to December 2015 were analyzed retrospectively. The cut-off value of CRP/Alb ratio was determined by the receiver operating characteristic(ROC) curve. According to the CRP/Alb ratio, patients were respectively divided into two groups: the high group(CRP/Alb ratio≥0.109) and the low group(CRP/Alb<0.109). The relationships between CRP/Alb ratio and clinical characteristics were analyzed by χ(2) test. Median survival and 1-year overall survival rate(OS) was calculated by Kaplan-Meier method.The risk factors of patients with poor prognosis were analyzed by univariate and multivariate Cox regression analysis model. Results: Tumor TNM stage(χ(2)=4.280, P=0.039) and differentiation(χ(2)=6.635, P=0.010) had significant relationship with CRP/Alb ratio. The median survival of higher CRP/Alb ratio group and lower CRP/Alb ratio group was 15 months and 23 months respectively. Compared with lower CRP/Alb ratio group, the 1-year OS of higher CRP/Alb ratio group decreased remarkablely, and the difference was statistically(χ(2)=10.207, P=0.001). Moreover, median survival and OS were decreased in patients with advanced age(≥65 years old: χ(2) =5.338, P=0.021), high TNM stage(ⅡB-Ⅲ: χ(2) =10.529, P=0.001), poor tumor differentiation(χ(2)=5.380, P=0.020), vascular invasion(χ(2) =7.856, P=0.005) and positive surgical margin(χ(2)=9.059, P=0.003). A high CRP/Alb ratio was identified as an independent risk factor of poor prognosis for patients with pancreatic cancer(HR=1.832, 95% CI: 1.067-3.144, P=0.028). Besides, old age(HR=1.684, P=0.014), high TNM stage(HR=1.666, P=0.031), vascular invasion(HR=1.834, P=0.024) and positive surgical margin(HR=2.205, P=0.023) were also included. Conclusion: Preoperative CRP/Alb ratio can be an important clinical factor for assessing the prognosis of patients with resectable pancreatic cancers, and high CRP/Alb ratio suggests poor prognosis.

[Effect of inhibiting perivascular adhesion on intimal hyperplasia of the vein grafts in rabbits].

Objective: To investigate the effect of preventing perivascular adhesion with topical application of sodium hyaluronate on intimal hyperplasia of the vein grafts in rabbits. Methods: Twenty-four male New Zealand white rabbits, aged 5 months, were randomly divided into 2 groups: Group A and B (n=12 rabbits per group). Artery defect model was established by cutting about 1 cm artery from the middle part of the dissociated left common carotid artery. A section about 3 cm was cut from the right external jugular vein, and the harvested vein was inverted and end-to-end anastomosed to the artery defect. After anastomosis, the adventitia and two anastomosis of the grafted veins in group A was applied 0.2 ml sodium hyaluronate locally to, and corresponding site in Group B was served as a control, but with the sterile normal saline. The grafted veins were obtained 1, 2 and 4 weeks after operation, HE staining and Masson staining were preformed for histological changes of grafted vein wall, proliferating cell nuclear antigen (PCNA) and platelet-derived growth factor (PDGF) immunohistochemistry staining were conducted for proliferation and expression and distribution of PDGF of the grafted vein. Results: The macroscopic and histological observation showed that the perivascular adhesions in Group A were looser when compared with those in Group B. The thickness of the intima, the degree of intima hyperplasia of 2 groups at different time points were as follows: at 1 week after operation, group A[(25.5±3.9) µm, (1.2±0.1) ]and group B[(26.2±4.2)µm, (1.2±0.1)]; at 2 weeks after operation, group A[(44.3±2.5)µm, (1.2±0.1)]and group B[(51.0±3.8)µm, (1.4±0.0)]; at 4 weeks after operation, group A[(69.9±6.8)µm, (1.5±0.1)] and group B[(84.4±6.4)µm, (1.7±0.1)]. Group A was inferior to group B in terms of the above three parameters 2 and 4weeks after operation (P<0.05). Cell proliferation index of intima and that of media were as follows: at 1 week after operation, group A (7.4±2.2), (21.5±3.2) and group B (11.5±2.0), (28.6±4.5); at 2 weeks, group A (20.0±3.2), (35.8±3.4) and group B (26.8±4.1), ( 42.6±4.2); at 4 weeks, group A (11.4±2.0), (22.1±2.7) and group B (15.5±2.4, 28.6±3.9). Group A was inferior to group B in terms of cell proliferation index of intima and media 1, 2 and 4 weeks after operation (P<0.05). The percentage of PDGF-positive cells of intima, media and adventitia was as follows: at 1 week after operation, group A (7.7±1.6), (19.6±3.7), (2.5±1.5) and group B (7.6±2.4), (20.6±4.4), (10.3±2.3); at 2 weeks after operation, group A (11.4±2.6), (19.8±3.1), (12.9±3.3) and group B (19.5±3.5), ( 30.6±5.2), (30.5±5.8); at 4 weeks after operation, group A (6.2±1.9), ( 11.1±2.8), (10.2±2.4) and group B (10.5±2.0), (18.6±3.2), (26.5±3.8). Group A was inferior to group B in terms of the percentage of PDGF-positive cells of intima, media and adventitia 2 and 4 weeks after operation (P<0.05) and Group A was inferior to group B that of adventitia 1 week after operation (P<0.05). Conclusion: Preventing perivascular adhesion with topical application of sodium hyaluronate can inhibit intimal hyperplasia.

[Dietary intake status of Chinese lactating women during the first month postpartum in 2013].

Objective: To assess the dietary intake status of Chinese lactating women during the first month postpartum. Methods: Data were extracted from Chinese National Nutrition and Health Surveillance, children aged 0-5 years and lactating women (2013). A total of 55 counties from 30 provinces in China (excluding the Tibet Autonomous Region) were selected using a multi-stage stratified cluster randomization sampling method. A group of 3 623 lactating women, at 1-6 months after delivery, were investigated in the study. The semi-quantitative food frequency questionnaire (FFQ) was used to collect information on frequencies and amounts of food consumed. Differences in food consumption rates and dietary intake in lactating women having different characteristics were analyzed and compared. Results: To eliminate abnormal values, 3 300 lactating women were included in the study. During the first month postpartum, food types with higher consumption rates were animal products (98.2%, 3 239) and vegetables (90.7%, 2 987), in addition to cereals (100%) and liquids (100%). The consumption rate of fruits was 67.4% (2 222) and the lowest consumption rate was for dairy products (38.3%, 1 262). The median intake of cereals, vegetables, fruits and animal products were 247.8, 150.0, 40.0 and 178.6 g/d, respectively. The daily median intake of dairy products and soybean/nut products was 0.0 g/d. Overall, the lactating women consumed 895.7 ml/d liquids. About 49.3% (1 627) of the subjects consumed less than the recommended intake for animal products in Chinese Dietary Guideline (2016). More than 50% of the lactating women consumed less than the recommended intakes for the other types of food, especially dairy, soybean/nut and liquids. The consumption rates for dairy products were 26.9%, 29.4%, 31.8% and 33.8% and those for soybean/nut products were 33.9% , 35.8% , 37.5% and 41.7% for the lactating women living in rural areas, with educations at junior high school level and below, with average family incomes under 15 000 yuan per capita in 2012 and who work as household mothers, respectively. These consumption rates for dairy and soybean/nuts were significantly lower than those in women living in cities (48.4%, 55.0%), with an education level of senior high school or above (48.8%, 55.7%), with average family income over 15 000 yuan per capita in 2012 (45.5%, 52.8%) and who work outside the home (43.7%, 49.4%). P values were <0.05 for all comparisons. Conclusion: The daily intake of all foods by lactating women during the first month postpartum was lower than the levels recommended in Chinese Dietary Guideline (2016). The consumption rate of dairy and soybean/nut products during this time period was low, especially for those living in rural areas, with education levels of junior high school and below, with average family incomes less than 15 000 yuan per capita in 2012 and who are housemothers.

[Risk factors for prevalence of folic acid deficiency in Chinese lactating women in 2013].

Objective: The study aimed to assess the folic acid status of lactating women in China and to analyze factors related to folic acid deficiency in these subjects. Methods: The data on lactating women were extracted from the Chinese National Nutrition and Health Surveillance in 2013. By a multi-stage stratified cluster random sampling method, 10 331 lactating women were selected for the study. The lactating women, 0-24 months postpartum, were from 55 sites in 30 provinces of China, excluding the Tibet Autonomous Region. A standard questionnaire was used to obtain general information and dietary intake during the previous one month period was collected using a food frequency questionnaire. A total of 20% of the total number of lactating women were randomly selected to analyze serum folic acid. Finally, 1 894 lactating women, with questionnaire results and serum folic acid data, were included in the study. Serum folic acid concentrations were analyzed using an electro-chemiluminescence immunoassay method. Folic acid deficiency was defined as a serum folic acid level <2 ng/ml. A multiple logistic regression analysis was used to analyze the factors associated with folic acid deficiency in these women. Results: After excluding abnormal values, 1 894 lactating women were included in the study. Based on our findings, the prevalence of folate deficiency was 3.0% (56/1 894) in lactating women in China. The prevalence of folic acid deficiency was 0.3% (1/388), 1.3% (7/550), 6.0% (38/639) and 3.2% (10/317) in larger, medium or small cities, general rural counties and poor rural counties, respectively. The prevalence of folic acid deficiency was 6.3% (17/269) and 2.4% (39/1 623) for minority and Han ethnic groups, respectively, and was 6.3% (52/823) and 0.4% (4/1 071) for subjects in northern and southern areas of China, respectively. Binary unconditionally logistic regression was used to analyze the factors associated with folic acid deficiency in the lactating women. The results showed that, compared with those living in the south and those in the Han ethnic group, those living in the north and belonging to the minority ethnic group had a greater risk of folic acid deficiency, with (OR=3.63, 95% CI: 1.64-8.05) and (OR=5.42, 95% CI: 1.75-16.74), respectively. With each month of age during childhood, the prevalence of folic acid deficiency decreased by 10% (OR=0.90, 95%CI: 0.85-0.96). Compared with low income subjects, those with middle incomes had OR (95%CI) of 0.25 (0.10-0.60) for folic acid deficiency. A lesser intake of cereal was associated with a greater risk of folic acid deficiency in lactating women (OR=3.04, 95%CI: 1.18-7.79). A lesser intake of tubers was a protective factor for folic acid deficiency in lactating women (OR=0.29, 95% CI:0.12-0.70). Conclusion: The folic acid status of Chinese lactating women has, in general, recently improved. However, living in northern areas, during early lactating periods, belonging to an ethnic minority, living in rural areas, having a low income, lower intake of cereal and excessive intake of tubers were risk factors for folic acid deficiency in lactating women. In these women, folic acid intervention should be considered a priority.

[Nutritional status and influence of vitamin D among Chinese lactating women in 2013].

Objective: To analyze serum vitamin D levels in Chinese lactating women, in 2013, and to evaluate their vitamin D nutritional status and influencing factors. Methods: Data were from the Chinese National Nutrition and Health Surveillance in 2013. Using the multistage stratified cluster sampling method, serum samples from lactating women, at 0-24 months postpartum, were obtained from 55 sites in 30 provinces of China, excluding the Tibet Autonomous Region. The concentration of serum vitamin D was determined by mass spectroscopy. A standard questionnaire was used to obtain basic information and the season of blood collection. Dietary information for one recent month was collected using a food frequency questionnaire. A total of 1 981 lactating women were included in the study. A multiple logistic regression model was used to analyze the factors related to vitamin D levels among lactating women. Results: The mean vitamin D level was (16.6±6.5) ng/ml, the prevalence of vitamin D deficiency (VDD) (vitamin D<12 ng/ml) was 25.2% (499 cases) and the prevalence of vitamin D inadequacy (12 ng/ml≤vitamin D<20 ng/ml) was 45.4% (900 cases). Compared with in the Han ethnic group, the OR value of VDD was 13.37 for Muslim ethnic women. Compared with women having a junior high school education or below, the OR value of VDD was 1.40 for those women with an educational level of senior high, middle school or above. Compared with housewives or nonworking women, the OR value of VDD was 1.62 for professional women. Compared with women living in general rural settings, the OR values of VDD for women living in large cities, medium and small cities or poor rural settings were 1.99, 1.46 and 2.66 respectively. Compared with the women surveyed in the fall, the OR value of VDD was 2.19 for the women surveyed in winter or spring. The VDD prevalence increased with higher latitude (OR=1.12) and decreased with increased meat consumption per day (OR= 0.73). (P<0.05 for all comparisons). Conclusion: Vitamin D deficiency and vitamin D inadequacy were common in lactating women in China. Those with increased risk of VDD included lactating women who were ethnic Muslims, with higher education levels, engaged in a professional occupation, living in higher latitude region and were surveyed in winter and spring.

[Prevalence of and risk factors for delayed onset of lactation in Chinese lactating women in 2013].

Objective: To study the prevalence of delayed onset of lactation (later than 3 days) in lactating women in China and to analyze its influencing factors. Methods: Data were extracted from Chinese National Nutrition and Health Surveillance-Mothers, from mothers with children under 2 years of age (in 2013). A total of 11 178 women who were lactating or had lactated were selected from 55 counties of 30 provinces (excluding the Tibet Autonomous Region) in China, using the multi-stage stratified cluster randomization sampling method. Basic information, including onset of lactation, initiation of breastfeeding, breastfeeding difficulties and breastfeeding knowledge were collected using a questionnaire investigation. The prevalence of delayed onset of lactation were analyzed by the weighted processing of complex sampling from the 6th national population census data. A multiple logistic regression was used to analyze the factors associated with delaged onset of lactation. Results: Among 11 178 lactating women, 3 388 had an onset of lactation later than 3 d. The prevalence of delayed onset of lactation was 30.3%. After complex weighting, the prevalence of delayed onset of lactation was 31.2% (95% CI: 25.7%-36.8%) for lactating women in China. Delivery by Caesarean section (OR=1.28, 95%CI: 1.06-1.53) and initiating breastfeeding ≥4 h (OR= 2.34, 95%CI: 1.76-3.11) were the negative factors for delayed onset of lactation. Compared with those living in large cities, lactating women living in medium or small cities (OR=1.39, 95%CI: 1.05-1.84) had a higher risk of delayed onset of lactation. Compared with the lactating women doing housework, the risk of delayed onset of lactation was lower (P<0.05) among those whose occupations were as leaders of Enterprises/Institutions (OR=0.68, 95%CI: 0.47-0.99), in catering and service trades (OR=0.61, 95%CI: 0.43-0.86), in agriculture/forestry/fishery/herdsmen fields (OR=0.65, 95%CI: 0.44-0.96) and who were unemployed (OR= 0.64, 95%CI: 0.46-0.90). Breastfeeding education during pregnancy might lower the risk of delayed onset of lactation (OR=0.78, 95% CI: 0.62-0.98). Conclusion: The prevalence of delayed onset of lactation was relatively high for Chinese lactating mothers. Caesarean section and late initiation of breastfeeding were the primary risk factors. Lactating mothers living in medium or small cities and those doing housework appear to be high-priority groups for intervention. Based on our findings, breastfeeding education during pregnancy is recommended to lower the risk of delayed onset of lactation.

[The status of postpartum weight retention and its associated factors among Chinese lactating women in 2013].

Objective: To analyze the status of postpartum weight retention and its associated factors among Chinese lactating women in 2013. Methods: This study was based on the databank of Chinese National Nutrition and Health Surveillance in 2013. Using the multi-stage stratified cluster sampling method, we enrolled 12 514 women, at 0-24 months postpartum, from 55 sites in 30 provinces of China (excluding the Tibet Autonomous Region). Questionnaires were used to collect data on basic characteristics, physical activity, lifestyle, food intake, pre-pregnancy weight, weight before delivery, disease history during pregnancy, delivery date, delivery mode, parity and breastfeeding information. Current body weight and height of each subject were measured. Postpartum weight retention in each subject was calculated as the difference between pre-pregnancy and current weights. High postpartum weight retention was defined as ≥5 kg. Survey sample weights were calculated according to the sampling design and number of children under 2 years old from 2010 population census data of China. Associated factors of high postpartum weight retention were identified by multiple logistic regression analysis. Results: A total of 9 972 women were included in this study. P50 (P25-P75) of weight retention for participants was 3.6 (0.2-7.3) kg and high weight retention accounted for 41.5% of the subjects (4 134/9 972). The weighted means (SE) of weight retention was 3.5 (0.1) kg, and it was at 0 to <3, 3 to <6, 6 to <9, 9 to <12, 12 to <18 and 18 to <24 months postpartum were 5.3 (0.2), 4.5 (0.2), 3.8 (0.2), 3.1 (0.2), 2.8 (0.2) and 3.0 (0.2) kg, respectively. The weighted proportion of high postpartum weight retention was 37.4% (95%CI: 36.0%-38.9%). Compared with women aged under 25 years old, the odds ratio of high postpartum weight retention was 1.31 for women over 30 years old. Compared with women at 18 to <24 months postpartum, the odds ratio of high postpartum weight retention was 2.67, 1.61 and 1.31 for women at 0 to <3, 3 to <6 and 6 to <9 months postpartum, respectively. Compared with women having a pre-pregnant BMI from 18.5 to <25.0 kg/m2, the odds ratio of high postpartum weight retention was 1.30 and 0.67 for women having pre-pregnant BMI <18.5 kg/m2 and ≥25.0 kg/m2, respectively. Compared with women having appropriate gestational weight gain, the odds ratio of high postpartum weight retention was 0.47 and 2.24 for women having low and excessive gestational weight gains, respectively. Compared with farmers, the odds ratio of high postpartum weight retention was 1.44 for housewives. (P<0.05 for all comparisons). Conclusion: Postpartum weight retention in Chinese lactating women is at an intermediate level. High postpartum weight retention is primarily associated with age, postpartum period, pre-pregnant BMI, gestational weight gain and career. The key control factor for weight retention is gestational weight gain, and 1 year postpartum is critical period for weight recovery.

Methanotrophs, methanogens and microbial community structure in livestock slurry surface crusts.

AIMS: Crusts forming at the surface of liquid manure (slurry) during storage have been shown to harbour a potential for mitigating CH4 emissions. This study investigated the microbial community in surface crusts, with a focus on micro-organisms related to CH4 metabolism. METHODS AND RESULTS: Microbial communities in four crusts from cattle and swine slurries were investigated using denaturing gradient gel electrophoresis and tag-encoded amplicon pyrosequencing. All crusts had distinct compositions of bacteria and archaea. The genera Methylobacter, Methylomicrobium, Methylomonas, and Methylosarcina of Type I, and Methylocystis of Type II, dominated the methane-oxidizing bacteria (MOB) community, whereas Methanocorpusculum was the predominant methanogen. Higher numbers of operational taxonomic units (OTUs) representing Type I than Type II MOB were found in all crusts. Potential CH4 oxidation rates were determined by incubating crusts with CH4 , and CH4 oxidization was observed in cattle, but not in swine slurry crusts. CONCLUSIONS: Slurry surface crusts harbour a diverse microbial community. Type I MOB are more diverse and abundant than Type II MOB in this environment. The distinct CH4 oxidation rates could be related to microbial compositions. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first to present the overall microbial community structure in slurry surface crusts. A better understanding of microbial community in surface crusts could support strategies for mitigation of CH4 emissions from livestock manure management.

[Clinical characteristics of myeloid tumors combined with the proliferation of large granular lymphocytes].

Myeloid neoplasms (MNs) belong to a group of hematological malignancies characterized by the abnormal biological functions of hematopoietic stem progenitor cells. The abnormal immune and hematopoietic microenvironment of patients with MN interact with malignant clonal hematopoietic stem cells, promoting the occurrence and development of their diseases. MN large granular lymphocyte proliferation (MN-LGLP) is a special and rare clinical phenomenon in this type of disease. Currently, research on this disease in domestic and international cohorts is limited. This study analyzes the clinical and laboratory characteristics of this type of patient and explores the impact of LGLP on the clinical characteristics and survival of patients with MN. Patients with MN-LGLP are prone to neutropenia and splenomegaly. The presence of LGLP is not a risk factor affecting the survival of patients with MN-LGLP. STAG, ASXL1, and TET2 are the most common accompanying gene mutations in MN-LGLP, and patients with MN-LGLP and STAG2 mutations have poor prognoses.

Tuning nano-skyrmions and nano-skyrmioniums in Janus magnets.

We study non-trivial spin textures, nanoscale magnetic skyrmions and skyrmioniums, in two-dimensional (2D) Janus magnets, such as MnSTe and MnSeTe, based on the micromagnetism approach and Landau-Lifshitz-Gilbert (LLG) equation. It is found that the Janus magnetic structures can host stable Néel nano-skyrmions with sub-10 nm diameters, and skyrmioniums with zero topological charge. The skyrmion size can be squeezed by external magnetic fields, and even the topological charge can be changed. The diameters of the skyrmioniums are about twice the size of the skyrmions. Moreover, the switching of the topological charge Q = ±1 can be realized by changing the direction of the external magnetic fields. Our results clearly show that magnetic skyrmions in Janus magnets can be used to construct new types of efficient spintronic nanodevices.

[Comparative study of medical common data models for FAIR data sharing].

The common data model (CDM) is an important tool to facilitate the standardized integration of multi-source heterogeneous healthcare big data, enhance the consistency of data semantic understanding, and promote multi-party collaborative analysis. The data collections standardized by CDM can provide powerful support for observational studies, such as large-scale population cohort study. This paper provides an in-depth comparative analysis of the data storage structure, term mapping pattern, and auxiliary tools development of the three international typical CDMs, then analyzes the advantages and limitations of each CDM and summarizes the challenges and opportunities faced in the CDM application in China. It is expected that exploring the advanced technical concepts and practical patterns of foreign countries in data management and sharing will provide references for promoting FAIR (findable, accessible, interoperable, reusable) construction of healthcare big data in China and solving the current practical problems, such as the poor quality of data resources, the low degree of semantization, and the inabilities of data sharing and reuse.