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Due to many unforeseen circumstances that could happen in the today's bulk power system, there is a possibility of a system wide outage. In order to provide aids to the power system dispatchers following a complete collapse of the power system, a prototype package has been developed. Through interactive and friendly graphic interface, the package suggests a guideline for the dispatcher to restore the power system. With an aim to increase the ease of maintenance, object-oriented technique was adopted to implement the package. The development of the software involved three stages: 1) Object oriented analysis, 2) Object oriented design, and 3) Integration and testing. In this paper, the structure and the development procedure of the prototype system are presented. Keywords - power system restoration, object-oriented technique

TiO2/g-C3N4 2D/2D heterojunction nanocomposites were successfully synthesized through a facile self-assembly method. The structure characterization results shows good interaction between TiO2 nanosheets and g-C3N4 nanosheets. The photocatalytic activity of TiO2/g-C3N4 samples were measured by hydrogen production in water splitting under visible light irradiation, which was found that the composites enhance the photocatalytic activity clearly compared to pure g-C3N4 and TiO2 nanosheets. The results could attribute to the formation of 2D heterojunction because of the stimulative charge transfer, promotional separation efficiency of photoexcited electron and hole and the suitable band positions. Besides, the samples exhibited substantial stability under visible light irradiation by the recycling experiments. The feasible photocatalytic mechanism was minutely discussed, which could explain the enhanced photocatalytic activity. [ABSTRACT FROM AUTHOR]

Endothelial cells play a critical role in maintaining vascular function and kinetic homeostasis, but excessive accumulation of palmitic acid (PA) may lead to endoplasmic reticulum stress and trigger endothelial cell dysfunction. Baicalin (BCL), a natural plant extract, has received widespread attention for its biological activities in anti-inflammation and anti-oxidative stress. However, the mechanism of BCL on PA-induced endothelial cell dysfunction is unclear. Therefore, the aim of this study was to investigate whether BCL could inhibit PA-induced endoplasmic reticulum stress and thus attenuate endothelial cell dysfunction.Human umbilical vein endothelial cells (HUVECs) were divided into Control, PA, PA + BCL-10 μM, PA + BCL-20 μM, and PA + BCL-50 μM groups. The PA group was treated with PA (200 μM), while the PA + BCL groups were co-treated with different concentrations of BCL (10 μM, 20 μM, 50 μM) for 24 hours. Cell viability was detected by MTT. Cell migration ability was determined by Transwell assay, apoptosis level by flow cytometry, and tube formation ability by tube formation assay. Finally, the levels of apoptosis-related proteins (Bax, Bcl-2, and cleaved caspase-3) and angiogenesis-related proteins (VEGFA and FGF2) were detected by western blot, MMP-9, as well as the protein levels of endoplasmic reticulum stress biomarkers (GRP78, CHOP, PERK, and ATF4).The results at the cellular level showed that cell viability, migration ability and tube formation ability of PA-induced HUVECs were significantly reduced, while apoptosis level was significantly increased. However, administration of different concentrations of BCL significantly enhanced PA-induced cell viability, migration ability and tube formation ability of HUVECs while inhibiting apoptosis. The results of protein levels showed that the protein levels of Bax and cleaved caspase-3 were observably up-regulated in the cells of the PA group, while the protein level of Bcl-2 was significantly down-regulated; compared with the PA group, the protein levels of Bax and cleaved caspase-3 were much lower and the Bcl-2 protein level was much higher in the PA + BCL group. Additionally, the protein levels of VEGFA, FGF2 and MMP-9 were raised and those of GRP78, CHOP, PERK and ATF4 were lowered in the PA + BCL group of cells in a concentration-dependent manner.BCL significantly attenuates PA-induced endothelial cell dysfunction by inhibiting endoplasmic reticulum stress. [ABSTRACT FROM AUTHOR]

Background: To analyze the risk factors for the development of avascular necrosis (AVN) of the femoral head after reduction surgery in children with developmental hip dysplasia (DDH), and to establish a prediction nomogram. Methods: The clinical data of 134 children with DDH (169 hips) treated with closure reduction or open reduction from December 2016 to December 2019 were retrospectively analyzed. Independent risk factors for AVN after DDH reduction being combined with cast external immobilization were determined by univariate analysis and multivariate logistic regression and used to generate nomograms predicting the occurrence of AVN. Results: A total of 169 hip joints in 134 children met the inclusion criteria, with a mean age at surgery of 10.7 ± 4.56 months (range: 4–22 months) and a mean follow-up duration of 38.32 ± 27.00 months (range: 12–94 months). AVN developed in 42 hip joints (24.9%); univariate analysis showed that the International Hip Dysplasia Institute (IHDI) grade, preoperative development of the femoral head ossification nucleus, cartilage acetabular index, femoral head to acetabular Y-shaped cartilage distance, residual acetabular dysplasia, acetabular abduction angle exceeding 60°, and the final follow-up acetabular index (AI) were associated with the development of AVN (P < 0.05). Multivariate logistic regression analysis showed that the preoperative IHDI grade, development of the femoral head ossification nucleus, acetabular abduction angle exceeding 60°, and the final follow-up AI were independent risk factors for AVN development (P < 0.05). Internal validation of the Nomogram prediction model showed a consistency index of 0.833. Conclusion: Preoperative IHDI grade, preoperative development of the femoral head ossification nucleus, final AI, and acetabular abduction angle exceeding 60° are risk factors for AVN development. This study successfully constructed a Nomogram prediction model for AVN after casting surgery for DDH that can predict the occurrence of AVN after casting surgery for DDH. [ABSTRACT FROM AUTHOR]

We investigated associations between dampness in Chinese homes and sick building syndrome (SBS) symptoms and studied the role of climate, family size, cleaning and ventilation for dampness, mould and SBS. A questionnaire survey was done in 2019–2020 among adults in five cities (32349 participants) and data on outdoor climate was collected. Multilevel logistic regression was used to calculate adjusted odds ratios (ORs). In total, 2.2% had rhinitis, 1.8% eye, 1.6% throat and 2.9% skin symptoms, 2.1% headache and 8.7% fatigue (weekly symptoms). Overall, 12.1% reported indoor mould, 5.7% damp bedding, 5.3% mould odour and 33.8% humid air in current home. Mould was associated with all symptoms (ORs 1.86–2.15 for minor mold growth and 1.65–3.45 for major mould growth). Damp bedding was associated with all symptoms (ORs 2.18–2.80 for minor dampness and 2.51–8.03 for major dampness). Mould odour was associated with all symptoms (ORs 1.84–2.77 for sometimes odour and ORs 3.78–7.80 for weekly odour). Perception of humid air was associated with all symptoms. ORs increased by number of dampness signs. Precipitation, outdoor relative air humidity and temperature increased dampness, mould and SBS symptoms. Large family size increased dermal symptoms. Daily floor cleaning, airing in winter, putting bedding to sunshine and mechanical ventilation in the bathroom reduced dampness, mould and SBS symptoms. In conclusion, mould and dampness in Chinese homes can increase rhinitis and SBS-symptoms in a dose-response manner. A warmer and more humid climate can increase, and cleaning and ventilation in the home can decrease dampness, mould and SBS symptoms. • Mould and dampness can increase medical symptoms in adults in a dose-response manner. • Precipitation, temperature and air humidity can increase domestic dampness and mould. • Precipitation, temperature and relative air humidity can increase medical symptoms. • Cleaning and putting bedding to sunshine can reduce dampness, mould and symptoms. • Airing and mechanical ventilation can reduce dampness, mould and medical symptoms. [ABSTRACT FROM AUTHOR]

Despite mounting evidence linking asthma to air pollution, it remains unclear which specific pollutant(s) exposure during critical time window(s) plays a pivotal role in the development of asthma. The objective of this study is to investigate the effects of intrauterine and postnatal air pollution exposure on children's asthma. From 2019 to 2020, a retrospective cohort study was conducted in Changsha, China. The inverse distance weighted (IDW) method was used to estimate each child's personal exposure to outdoor air pollutants at their home address. Associations between personal air pollution exposure and asthma were comprehensively examined. The occurrence of children's asthma was found to be linked to exposure to PM 2.5 and NO 2 during both the intrauterine and current periods, with significant ORs (95% CI) of 1.44 (1.08–1.93) and 1.29 (1.00–1.68) for IQR increase in intrauterine exposure particularly during the 2nd trimester, and 1.26 (1.01–1.57) and 1.26 (1.04–1.51) for exposure in previous year. Post-natal PM 10 exposure was linked to asthma, with an OR (95% CI) of 1.28 (1.01–1.62). Higher risks of asthma were associated with intrauterine exposure to PM 2.5 and postnatal exposure to PM 10. The critical time windows for PM 2.5 , PM 2.5-10 , and PM 10 exposure were identified as the entire pregnancy, the second trimester, and the entire postnatal period, respectively. Cumulative exposure to PM 2.5 and NO 2 during gestational weeks had a notable impact on asthma. Additionally, exposure to traffic-related air pollution (TRAP) at all timing stages, as well as PM 2.5-10 and SO 2 at night, increased the risk of asthma. Certain subgroups were more vulnerable to asthma risk due to air pollution. Children's asthma was predominantly influenced by exposure to particulate matters and TRAP during both the intrauterine and postnatal periods. [Display omitted] • Traffic-related air pollution (TRAP) exposure was related with childhood asthma. • Pregnancy, 2nd trimester, and postnatal period were critical widows for PM exposure. • Daytime and nighttime TRAP exposure played an important role in the risk of asthma. • There were cumulative effects of PM 2.5 and NO 2 over gestation in relation to asthma. • Our study supports and develops the "fetal origin of childhood asthma" hypothesis. [ABSTRACT FROM AUTHOR]

Despite mounting evidence linking outdoor air pollution with otitis media (OM), the role of air pollutant(s) exposure during which critical window(s) on childhood OM remains unknown. We sought to identify the key air pollutant(s) and critical window(s) associated with the onset and recurrent attacks of OM in kindergarten children. A combined cross-sectional and retrospective cohort study involving 8689 preschoolers aged 3–6 years was performed in Changsha, China. From 2013–2020, data on air pollutants were collected from ambient air quality monitoring stations in Changsha, and the exposure concentration to each child at their home address was calculated using the inverse distance weighted (IDW) method. The relationship between air pollution and OM in kindergarten children was studied using multiple logistic regression models. Childhood lifetime OM was associated with PM 2.5 , SO 2 and NO 2 , with ORs (95% CI) of 1.43 (1.19–1.71), 1.18 (1.01–1.37) and 1.18 (1.00–1.39) by per IQR increase in utero exposure and with PM 2.5 , PM 2.5–10 and PM 10 , with ORs = 1.15 (1.00–1.32), 1.25 (1.13–1.40) and 1.49 (1.28–1.74) for entire post-natal exposure, respectively. The 2nd trimester in utero and the post-natal period, especially the 1st year, were key exposure time windows to PM 2.5 and PM 10 associated with lifetime OM and the onset of OM. Similarly, the 4th gestational month was a critical window for all pollutants except CO exposure in relation to lifetime OM and OM onset, but not recurrent OM attacks. PM 2.5 exposure during the nine gestational months and PM 10 exposure during the first three years had cumulative effects on OM development. Our subgroup analysis revealed that certain children were more susceptible to the OM risk posed by air pollution. Early-life exposure to air pollution, particularly PM 2.5 during the middle of gestation and PM 10 during the early post-natal period, was associated with childhood OM. [Display omitted] • Children's otitis media (OM) is mainly affected by pre-natal PM 2.5 and post-natal PM 10 exposures. • The 2nd trimester and the first year are critical windows for PM 2.5 and PM 10 exposures, respectively. • The 4th gestational month is critical for pollution exposure in relation to lifetime OM and OM onset. • Cumulated pre-natal PM 2.5 and post-natal PM 2.5–10 and PM 10 exposures play key roles in OM risk. • Our study supports and expands upon the "fetal origin of OM" hypothesis. [ABSTRACT FROM AUTHOR]

Childhood pneumonia remains a major public health concern worldwide, but the critical meteorological factors that contribute to it are unknown. To investigate the relationship between childhood pneumonia and prenatal and postnatal exposure to meteorological factors to identify the critical factors and vulnerable timing windows. We conducted a retrospective cohort study of 8689 preschoolers in China. We gathered information on personal factors, health status, and indoor environment through questionnaires. We considered meteorological factors including temperature (mean, maximum, minimum), diurnal temperature variation (DTV), relative humidity, wind speed, rainfall, pressure and sunshine during early life. Using multiple logistic regression models, we investigated the links between childhood pneumonia and early life exposure to meteorological factors. Exposure to mean, maximum, and minimum temperatures was associated with childhood pneumonia in the first month and first trimester, with ORs (95% CI) of 1.32 (1.07–1.62), 1.26 (1.04–1.52) and 1.33 (1.08–1.64) in the first month, and 1.42 (1.12–1.81), 1.36 (1.08–1.71) and 1.47 (1.15–1.88) in the first trimester for per IQR increase in each meteorological factor exposure. Wind speed, rainfall, and sunshine exhibited significant associations with pneumonia during the first, second, and third trimesters, respectively. Exposure to various temperatures, DTV, relative humidity, rainfall, air pressure, and sunshine were linked to childhood pneumonia in the postnatal period, particularly in the previous year. The sensitivity analysis revealed that boys are more vulnerable to meteorological factors. Keeping dogs or plants may offer protection against the pneumonia risk of prenatal and postnatal meteorological exposure. Exposure to meteorological factors during both the prenatal and postnatal periods, especially in early pregnancy, was found to elevate the risk of childhood pneumonia. [Display omitted] • Effect of climatic factors on childhood pneumonia in different windows is unclear. • Pneumonia in children was associated with prenatal exposure to ambient temperature. • Early pregnancy was identified as a critical time window for climatic exposure. • Postnatal exposure to climatic factors had the highest risk of childhood pneumonia. • Our study support "Fetal origin of pneumonia" hypothesis by meteorological factors. [ABSTRACT FROM AUTHOR]