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In general, tests for indoor air quality are categorized as either field tests or laboratory tests. Controlling indoor gas-phase chemical contaminants involves three aspects: pollution source control, contaminant dispersion control (including ventilation dilution and air flow organization) and air cleaning techniques. For both field tests and laboratory tests or any of the aspects of controlling indoor air quality, real-time monitoring of organic compounds is very important, particularly to show temporal indoor contaminants and their continuous concentration variations. In the field tests for determining indoor air quality or human exposure to harmful pollution, real-time monitoring is necessary because the pollution concentration tends to vary greatly over time and space (Ezzati, Mbinda and Kammen, 2000; Lai et al., 2004; Lirk, Bodrogi and Rieder, 2004; Stefaniak et al., 2000). The available research on indoor VOC source/sink behavior falls into two categories: experimental studies and modeling. The literature concerned with the experimental approach to studying the characteristics of VOC emissions from building materials is extensive, and includes descriptions of various methods such as the chamber method (ASTM, 1997, 2001), the FLEC method (Wolkoff, 1996), the CLIMPAQ method (Gunnarsen, Nielsen and Wolkoff, 1994) etc. In most cases a real-time technique of monitoring the instantaneous VOC concentration in the tested space is needed. Even in the modeling research such as Little, Hodgson and Gadgil (1994), Cox, Little and Hodgson (2001a, 2001b), Guo (2002a, 2002b), Xu and Zhang (2003, 2004), Deng and Kim (2004) etc., the determination of key parameters of VOC emissions such as the diffusion coefficient, partition coefficient etc. is based upon measurements some of which also require accurate realtime VOC concentration measurement. The real-time monitoring of some species concentration distribution in indoor air is an effective way to evaluate the dispersion of fresh air and/or gas-phase chemical pollutants, for example when determining the ventilation effectiveness, the air exchange rate (ACH) or the air age distribution for a given space (Park et al., 1998; Shin et al., 2005). It also provides a helpful validation for transient

The COVID-19 pandemic has led to considerable morbidity and mortality, and consumed enormous resources (e.g. energy) to control and prevent the disease. It is crucial to balance infection risk and energy consumption when reducing the spread of infection. In this study, a quantitative human, behavior-based, infection risk-energy consumption model for different indoor environments was developed. An optimal balance point for each indoor environment can be obtained using the anti-problem method. For this study we selected Wangjing Block, one of the most densely populated places in Beijing, as an example. Under the current ventilation standard (30 m

International audience; When circularly polarized light interacts with a nanostructure, the optical response depends on the geometry of the structure. If the nanostructure is chiral (i.e., it cannot be superimposed on its mirror image), then its optical response, both in near-field and far-field, depends on the handedness of the incident light. In contrast, achiral structures exhibit identical far-field responses for left- and right-circular polarization. Here, we show that a perfectly achiral nanostructure, a plasmonic metamolecule with trigonal D3h symmetry, exhibits a near-field response that is sensitive to the handedness of light. This effect stems from the near-field interference between the different plasmonic modes sustained by the plasmonic metamolecule under circularly polarized light excitation. The local chirality in a plasmonic trimer is then experimentally evidenced with nanoscale resolution using a molecular probe. Our experiments demonstrate that the optical near-field chirality can be imprinted into the photosensitive polymer, turning an optical chirality into a geometrical chirality that can be imaged using atomic force microscopy. These results are of interest for the field of polarization-sensitive photochemistry.

Background: The ongoing coronavirus disease (COVID-19) outbreak has placed the healthcare system and student training under considerable pressure. However, the plights of healthcare students in the COVID-19 period have drawn limited attention in China.Methods: A cross-sectional on-line survey was undertaken between January and March 2020 to explore the COVID-19 knowledge, attitude, and practice (KAP) survey among Chinese healthcare students. Demographic information and data on KAP were obtained using a self-reported questionnaire. The percentage KAP scores were categorized as good or poor. Independent predictors of good knowledge of COVID-19 were ascertained to use a logistic regression model.Results: Of the 1,595 participants, 85.9% (1,370) were women, 53.4% were junior college students, 65.8% majoring in nursing, and 29.8% had received training on COVID-19. The overall median percentage for good KAP was 51.6% with knowledge of 28.3%, attitude 67.8%, and practice 58.6%, respectively. Independent predictors of good knowledge of COVID-19 were being students ≥25 (95% CI = 0.27–0.93, P = 0.02), those taking bachelor degrees (95% CI = 1.17–2.07, P = 0.00), and those having participated in COVID-19 treatment training.Conclusions: The result of this study revealed suboptimal COVID-19-related KAP among healthcare students in China. To effectively control future outbreaks of COVID-19, there is a need to implement public sensitization programs to improve the understanding of COVID-19 and address COVID-19-related myths and misconceptions, especially among healthcare students.

Fe content and distribution on montmorillonite would probably enhance its sorption capacity for hydrophobic organic pollutants. Thus, Fe modified montmorillonites with different ratios of FeSO

A questionnaire survey on dermal symptoms and home environment was performed in eight Chinese cities (40 279 participants). Data on city level temperature, precipitation, PM10 , NO2, and gross domestic product (GDP) per capita were collected. In total, 2.2% had eczema, 2.4% facial erythema (FE) and 2.6% seborrheic dermatitis symptoms (SD). Higher temperature was associated with eczema (OR = 1.09). Higher GDP per capita was related to less SD. Higher PM10 was related to SD. Suburban living was protective for eczema (OR = 0.77) (vs. urban). Living in old buildings (built before 1991) was related to eczema (OR = 1.42). Living near heavily trafficked roads was related to FE (OR = 1.33) and SD (OR = 1.35). Having new furniture was related to all symptoms (OR = 1.26-1.47). Burning mosquito coils (OR = 1.37-1.57) and incense (OR = 1.33-1.37) were associated with eczema, FE, or SD. Presence of cockroaches and rats/mice was associated with FE or SD (OR = 1.31-1.40). Using air conditioner, daily cleaning and frequently exposing bedding to sunshine were protective (OR = 0.60-0.83). In conclusion, higher temperature, higher PM10 , urban living, living near heavily trafficked roads, old buildings, new furniture, burning mosquito coils and incense, and presence of cockroaches/rats/mice increased the risk of eczema, FE, or SD. Higher GDP, air conditioner, daily cleaning, and exposing bedding to sunshine were protective.

Increased public awareness of the health impacts of atmospheric fine particulate matter (PM2.5) has led to increased demand and deployment of indoor air cleaners. Yet, questions still remain about the effectiveness of indoor air cleaners on indoor PM2.5 concentrations and personal exposure to potentially hazardous components of PM2.5. Metals in PM2.5 have been associated with adverse health outcomes, so knowledge of their sources in urban indoor and outdoor areas and how exposures are influenced by indoor air cleaners would be beneficial for public health interventions. We collected 48-h indoor, outdoor, and personal PM2.5 exposure samples for 43 homes with asthmatic children in suburban Shanghai, China during the spring months. Two sets of samples were collected for each household, one set with a functioning air filter placed in the bedroom ("true filtration") and the other with a non-functioning ("sham") air cleaner. PM2.5 samples were analyzed for elements, elemental carbon, and organic carbon. The major sources of metals in PM2.5 were determined by Positive Matrix Factorization (PMF) to be regional aerosol, resuspended dust, residual oil combustion, roadway emissions, alloy steel abrasion, and a lanthanum (La) and cerium (Ce) source. Under true filtration, the median indoor to outdoor percent removal across all elements increased from 31% to 78% and from 46% to 88% across all sources. Our findings suggest that indoor air cleaners are an effective strategy for reducing indoor concentrations of PM2.5 metals from most sources, which could translate into improved health outcomes for some populations.

Few studies exist from China on associations between home environment and adult health. We studied associations between home environment factors (other than dampness and mould) and rhinitis, throat and dermal symptoms and headache and fatigue among young parents in six cities across China (N = 36,541). They were recruited as parents from day care centers selected randomly and answered a questionnaire on medical symptoms and the home environment. Odds ratios (OR) were calculated by multilevel logistic regression adjusting for gender, atopy, smoking, home size and dampness/mould. Overall, 4.8% had skin symptoms 3.1% rhinitis, 2.8% eye, 4.1% throat symptoms, 3.0% headache and 13.9% had fatigue (all as weekly symptoms). Redecoration was associated with rhinitis, eye and skin symptoms, headache and fatigue. New furniture was associated with eye, throat and skin symptoms and fatigue. Gas cooking was associated with eye and throat symptoms, headache and fatigue. Biomass cooking was associated with eye and throat symptoms and headache. Burning incense was associated with eye, throat and skin symptoms, headache and fatigue. Presence of cockroaches and mosquitos or flies was associated with all six symptoms. Rats or mice were associated with eye and dermal symptoms. Cat keeping was associated with eye symptoms while dog keepers had less fatigue. Living near major roads was associated with rhinitis, eye, throat and skin symptoms and fatigue. Daily cleaning, a mechanical ventilation system in the kitchen or in the bathroom, living in older buildings and living in less urbanized areas were protective factors. In conclusion, urbanization, traffic exhaust, indoor emissions from redecoration and new furniture, gas cooking and air pollution from burning incense and biomass may cause dermal and mucosal symptoms, headache and fatigue among adults in China. Indoor animals (cats, mice/rats, cockroaches) were other risk factors. Daily cleaning, mechanical ventilation and living in older buildings can be protective.

We surveyed 40 010 three- to six-year-old children in seven Chinese cities (Beijing, Taiyuan, Urumqi, Shanghai, Nanjing, Changsha, and Chongqing) during 2010-2012 so as to investigate possible links between home renovation and childhood eczema. Their parents responded to questions on home renovation and childhood eczema. Multivariate and two-level (city-child) logistic regression analyses yielding odds ratios with 95% confidence intervals were performed. Sensitivity analyses stratifying data for region, climate, and income level were also performed. The prevalences of childhood eczema in children with different floor and wall covering materials were significantly different and were significantly higher with home renovation during early lifetime. Exposure to synthetic materials significantly increased the risk of childhood eczema by 20%-25%. The risks (AOR, 95% CI) of current eczema among children in families with solid wood flooring and oil paint wall covering were 1.25 (1.04-1.49) and 1.35 (1.14-1.60), respectively. Home renovation during pregnancy was related to children's lifetime and current eczema.

Exposure to VOCs causes a variety of adverse health effects, with much of the exposure occurring at home during sleep. The use of an air cleaner maybe an effective and convenient way to reduce associated exposures and health risks. Studies about the impacts of air cleaner on VOCs are limited. The main objective of this paper was to assess the inhalation health risks that toxic VOCs present during nighttime sleep and to estimate the removal effectiveness of an indoor air cleaner on these VOCs. Asthmatic children, who are especially vulnerable to the detrimental effects of air pollutants, were recruited and the VOC concentrations in their bedrooms were measured during two periods - once with a true air cleaner and once with a sham air cleaner. Among the toxic VOCs quantified, formaldehyde, acetaldehyde and toluene had the highest concentrations (median: 18.0, 14.0 and 12.1 μg/m³, respectively) in the bedrooms. Health risk assessments were conducted to identify compounds of greatest concern. During nighttime sleep, 7 VOCs presented inhalation cancer risk above the acceptable risk (1 × 10−6), 4 VOCs exceeded the non-cancer risk threshold (1) in most of the homes tested. The results indicate that the use of an air cleaner in residences may lead to significant reductions in VOC concentrations indoors, but even with this reduction, the associated health risks are still of concern. This study highlights the need for reductions in toxic VOCs at home, points to the imminent need for improvements in control of VOC sources.

This study estimates adult mortalities attributed to PM2.5 across urban China in 2015 and the corresponding mortalities that might be avoided by meeting the yearly averaged indoor PM2.5 threshold i...

A reduced-scale (1:10) tunnel with four vertical shafts is constructed to investigate the fire smoke propagation in a natural ventilation tunnel equipped with large cross-sectional ceiling openings. A series of fire tests are performed to explore the impact of fire HRR (Heat Release Rate), shaft height and shaft interval on the gas temperature and smoke back-layering length. It is observed that the smoke cannot fill up the entire cross-section of the shaft, but just propagates adhering to the shaft sidewalls and then spills out of the tunnel. This flow mode of hot smoke in the large cross-sectional shaft is significantly different from the general plug-holing phenomenon, especially for the fresh air entrainment. In such case the fresh air is entrained just along the shaft sidewalls rather than exhausted directly from the lower part of the tunnel. Moreover, experimental results indicate that the dimensionless ceiling gas temperature on the upstream side of the shaft appears to be independent on the shaft height, while the temperature decay rate on the downstream side increases with the shaft height. The variation of the smoke back-layering length under different conditions implies that the smoke back-layering length initially decreases with the shaft height, then keeps constant with the HRRs when the HRRs are greater than 25.8 kW. Additionally, the smoke back-layering length generally increases with the fire-shaft interval when the shaft height is lower than 0.65 m, while it levels off initially and then increases again when the shaft height is higher than 0.65 m. Experimental testing in this paper contributes to understanding of the smoke movement in the naturally ventilated tunnel with large cross-sectional vertical shafts.

China has implemented two national clean air actions in 2013-2017 and 2018-2020, respectively, with the aim of reducing primary emissions and hence improving air quality at a national level. It is important to examine the effectiveness of such emission reductions and assess the resulting changes in air quality. However, such evaluation is difficult as meteorological factors can amplify, or obscure the changes of air pollutants, in addition to the emission reduction. In this study, we applied the random forest machine learning technique to decouple meteorological influences from emissions changes, and examined the deweathered trends of air pollutants in 12 Chinese mega-cities during 2013-2020. The observed concentrations of all criteria pollutants except O

Brillouin frequency shift (BFS) of distributed optical fiber sensor is extracted from the Brillouin gain spectrum (BGS), which is often characterized by Lorenz type. However, in the case of complex stress and optical fiber self damage, the BGS will deviate from Lorenz type and be asymmetric, which leads to the extraction error of BFS. In order to enhance the extraction accuracy of BFS, the Lorenz local single peak fitting algorithm was developed to fit the Brillouin gain spectrum curve, which can make the BSG symmetrical with respect to the Brillouin center frequency shift. One temperature test of a fiber-reinforced polymer (FRP) packaged sensor whose BSG curve is asymmetric was conducted to verify the idea. The results show that the local region curve of BSG processed by the developed algorithm has good symmetry, and the temperature measurement accuracy obtained by the developed algorithm is higher than that directly measured by demodulation equipment. Comparison with the reference temperature, the relative measurement error measured by the developed algorithm and BOTDA are within 4% and 8%, respectively.

The prognosis of patients with advanced urothelial carcinoma is dismal. Platinum-based chemotherapy is still the main first-line treatment for advanced urothelial carcinoma, while immunotherapy can be used as a first-line treatment option for people who cannot tolerate platinum. Immunotherapy is preferred in the second-line treatment of bladder urothelial carcinoma. PD-1 inhibitors (Pembrolizumab, nivolumab and atezolizumab) and PD-L1 inhibitors (Ddurvalumab and avelumab) have not been approved for the treatment of advanced urothelial cancer in China. We describe a patient with advanced urothelial carcinoma experienced disease progression after gemcitabine chemotherapy. Following a treatment of domestic PD-1 inhibitor (sintilimab), the patient achieved a durable complete response with mild toxicity. This case indicates that PD-1 inhibitor sintilimab might be a second-line treatment choice for advanced urothelial carcinoma.

Airborne particulate matters (PM) pose serious health threats to the population, and efficient filtration is needed for indoor and vehicular environments. However, there is an intrinsic conflict between filtration efficiency, air resistance, and service life. In this study, a two-stage electrostatically assisted air (EAA) filtration device is designed and the efficiency-air resistance-filter life envelope is significantly improved by a thin coating of polydopamine (PDA) on the polyethylene terephthalate (PET) coarse filter by in situ dopamine polymerization. The 8 mm thick EAA PDA-140@PET filter has a high filtration efficiency of 99.48% for 0.3 µm particles, low air resistance of 9.5 Pa at a filtration velocity of 0.4 m s-1 , and steady performance up to 30 d. Compared with the bare PET filter, the penetration rate for 0.3 µm particles is lowered by 20×. The coated PDA is of submicron thickness, 10-3 × the gap distance between filter fibers, so low air resistance could be maintained. The filter shows steadily high filtration efficiency and an acceptable increase of air resistance and holds nearly as many particles as its own weight in a 30 day long-term test. The working mechanism of the EAA coarse filter is investigated, and the materials design criteria are proposed.

Introduction Renal interstitial fibrosis, an important pathological feature of kidney aging and chronic renal failure, is regulated by mesenchymal stem cells (MSCs). We have previously demonstrated low expression of miR-133b in MSC-derived extracellular vesicles (MSC-EVs) in aged rats. However, miR-133b can mediate the inhibition of epithelial-mesenchymal transition (EMT) of renal tubules induced by transforming growth factor-β1 (TGF-β1). We investigated the effect of miR-133b for the treatment of geriatric renal interstitial fibrosis and evaluated its target genes. Methods We performed real-time polymerase chain reaction to detect miR-133b expression induced during EMT of HK2 cells by TGF-β1 at different concentrations (0, 6, 8, and 10 ng/mL) and at different time points (0, 24, 48, and 72 h). The target genes of miR-133b were validated using the dual-luciferase reporter assay. In vitro experiments were performed to evaluate mRNA and protein expression of miR-133b targets, E-cadherin, α-smooth muscle actin (SMA), fibronectin, and collagen 3A1 (Col3A1), in HK2 cells transfected with miR-133b under TGF-β1 stimulation. A 24-month-old unilateral ureteral obstruction (UUO) mouse model was established and injected with transfection reagent and miR-133b into the caudal vein. The target gene of miR-133b and other parameters mentioned above such as mRNA and protein expression levels and renal interstitial fibrosis were detected at 7 and 14 days. Results miR-133b expression gradually decreased with an increase in TGF-β1 concentration and treatment time, and the miR-133b mimic downregulated connective tissue growth factor (CTGF) expression. The dual-luciferase reporter assay confirmed CTGF as a direct target of miR-133b. Transfection of the miR-133b mimic inhibited TGF-β1-induced EMT of HK2 cells; this effect was reversed by CTGF overexpression. miRNA-133b expression significantly increased (approximately 70–100 times) in mouse kidney tissues after injection of the miRNA-133b overexpression complex, which significantly alleviated renal interstitial fibrosis in mice with UUO. Conclusion miR-133b exerted targeted inhibitory effects on CTGF expression, which consequently reduced TGF-β1-induced EMT of HK2 cells and renal interstitial fibrosis in aged mice with UUO.

Exposure to fine particulate matter (PM2.5) and ozone (O3) may lead to inflammation and oxidative damage in the oral cavity, which is hypothesized to contribute to the worsening of airway inflammation and asthma symptoms. In this panel study of 43 asthmatic children aged 5-13 years old, each child had 4 clinic visits with a 2-week interval between two consecutive visits. At each visit, saliva samples were collected and subsequently analyzed for interleukin 6 (IL-6) and eosinophil cationic protein (ECP) as biomarkers of inflammation and malondialdehyde (MDA) as a biomarker of oxidative stress in the oral cavity. At each visit, children were measured for fractional exhaled nitric oxide (FeNO) as a marker of pulmonary inflammation. Asthma symptoms of these children were measured using the Childhood Asthma Control Test (C-ACT). We found that an interquartile range (IQR) increase in 24-h average personal exposure to PM2.5 measured 1 and 2 days prior was associated with increased salivary IL-6 concentration by 3.0% (95%CI: 0.2%-6.0%) and 4.2% (0.7%-8.0%), respectively. However, we did not find a clear association between personal O3 exposure and any of the salivary biomarkers, except for a negative association between salivary MDA and O3 exposure measured 1 day prior. An IQR increase in salivary IL-6 concentration was associated with significantly increased FeNO by 28.8% (4.3%-53.4%). In addition, we found that increasing salivary IL-6 concentrations were associated with decreased individual and total C-ACT scores, indicating the worsening of asthma symptoms. We estimated that 13.2%-22.2% of the associations of PM2.5 exposure measured 1 day prior with FeNO and C-ACT scores were mediated by salivary IL-6. These findings suggest that the induction of inflammation in the oral cavity may have played a role in linking air pollution exposure with the worsening of airway inflammation and asthma symptoms.

The molecular mechanisms underlying the associations between air pollution exposure and adverse cardiopulmonary effects remain to be better understood. Altered amino acid metabolism may plays an important role in the development of cardiopulmonary diseases and may be perturbed by air pollution exposure. To test this hypothesized molecular mechanism, we conducted an association analysis from an existing intervention study to examine the relations of air pollution exposures with amino acids in 43 Chinese healthy adults. Plasma levels of amino acids were measured using a UPLC-QqQ-MS system. Time-weighted personal exposure to O3, PM2.5, NO2, and SO2 over four time windows, i.e., 12 h, 24 h, 1 week, and 2 weeks, were calculated using the measured indoor and outdoor concentrations coupled with the time-activity data for each participant. Linear mixed-effects models were used to estimate the associations between air pollutants at each exposure window and amino acids by controlling for potential confounders. We observed significant associations between exposures and plasma concentrations of amino acids, with the direction of associations varying by amino acid and air pollutant. While there is little evidence of associations for NO2 and SO2, the associations with amino acids were fairly pronounced for exposure to PM2.5 and O3. In particular, independent O3 (12- and 24-hour) associations were observed with changes in the amino acids that were related to the urea cycle, including aspartate, asparagine, glutamate, arginine, citrulline, and ornithine. Our findings indicated that air pollution may cause acute perturbation of amino acid metabolism, and that O3 and PM2.5 may affect the metabolism of amino acids in different pathways. Main finding: Acute air pollution exposure might affect the perturbation of amino acid metabolism, and in particular, was associated with amino acids in relation to the urea cycle.

Fine particulate matter (PM

Given a large fraction of people’s exposure to urban PM2.5 occur indoors, reducing indoor PM2.5 levels may offer a more feasible and immediate way to save substantial lives and economic losses attributable to PM2.5 exposure. We aimed to estimate the premature mortality and economic loss reductions associated with achieving the newly established Chinese indoor air guideline and a few hypothetical indoor PM2.5 guideline values. We used outdoor PM2.5 concentrations from 1497 monitoring sites in 339 Chinese cities in 2015, coupled with a steady-state mass balance model, to estimate indoor concentrations of outdoor-infiltrated PM2.5. Using province-specific time-activity patterns for urban residents, we estimated outdoor and indoor exposures to PM2.5 of outdoor origin. We then proceeded to use localized census-based concentration-response models and the value of statistical life estimates to calculate premature deaths and economic losses attributable to PM2.5 exposure across urban China. Finally, we estimated potentially avoidable mortality and corresponding economic losses by meeting the current 24-hour based guideline and various hypothetical indoor limits for PM2.5. In 2015 in urban areas of mainland China, the city-specific annual mean outdoor and indoor PM2.5 concentrations ranged 9–108 μg/m3 and 5–56 μg/m3, respectively. Indoor exposures contributed 62%–91% daily and 68%–83% annually to the total time-weighted exposures. The potential reductions in total deaths and economic losses for the scenario in which daily indoor concentrations met the current guideline of 75 μg/m3, 37.5 μg/m3, and 25 μg/m3 were 16.9 (95% CI: 0.7–62.1) thousand, 87.7 (95% CI: 9.7–197.7) thousand, and 165.5 (95% CI: 30.8–304.0) thousand, respectively. The corresponding reductions in economic losses were 5.7 (95% CI: 0.2–34.8) billion, 29.4 (95% CI: 2.4–109.6) billion, and 55.2 (95% CI: 7.7–168.0) billion US Dollars, respectively. Deaths and economic losses would be reduced exponentially within the range of 0–75 μg/m3 for hypothetical indoor PM2.5 limits. The findings demonstrate the effectiveness of reducing indoor concentrations of outdoor-originated PM2.5 in saving substantial lives and economic losses in China. The analysis provides quantitative evidence to support the implementation of an indoor air quality guideline or standard for PM2.5.

A novel PTH-derived peptide, PTHdP, including a repetitive aspartic acid sequence at the C-terminal and phosphorylated serine at the N-terminal has been previously designed. To evaluate its potential as a bone growth factor for bone tissue engineering, true bone ceramics incorporated with nanohydroxyapatite coating and chitosan (CH/TBC) was developed as a desired three-dimensional porous delivery carrier in this study. In vitro results showed that PTHdP could be loaded with high-efficiency and subsequently released in a controlled and sustained manner from CH/TBC. Bioactivity of released PTHdP was retained and able to exert a significant effect on promoting or inhibiting osteogenesis actions when exposed intermittently or continuously, respectively, for MC3T3-E1 cell culture. As evaluated in a critical-size rabbit radial defect model by radiographic and histological examination, the combination of CH/TBC scaffolds with PTHdP exhibited a remarkably stronger capacity to stimulate new bone formation than control and pure CH/TBC groups. These results indicated the novel PTHdP peptide achieved high affinity to bone mineral without interference in bioactivity, and local delivery of PTHdP from apatite materials could be a promising alternative for future bone tissue engineering.

We investigated associations between prenatal and postnatal environmental factors and onset and remission of preschool childhood eczema across China. The study population was preschoolers in randomized day care centers in seven cities (N = 39,782). Data on eczema and prenatal and postnatal indoor and outdoor environment were obtained from a cross-sectional questionnaire sent to parents or other guardians. Reports on eczema in the first 2 years and in the past year was used to retrospectively calculate onset and remission (changes of reported eczema). Prenatal and postnatal outdoor temperature, NO2 and PM10 were modelled from official air pollution data. Associations were estimated by two-level logistic regression. Calculated onset rate was 3.2%/y and remission rate 29.2%/y. Exposure to NO2 during pregnancy was associated with onset of eczema, similarly for all trimesters. Postnatal PM10 and NO2 were related to decreased remission. Postnatal outdoor temperature was associated with onset of eczema. Pre-natal and current redecoration or buying new furniture, and perinatal as well as current dampness and indoor mould, were associated with increased onset and decreased remission. Cockroaches in current home was another indoor risk factors. Prenatal exposure to farm environment and large family size were all negatively associated with eczema. In conclusion, a warmer climate and prenatal NO2 can be associated with increased onset of eczema in Chinese preschoolers. Postnatal PM10 and NO2 can be associated with reduced remission. Perinatal and current dampness, indoor mould and cockroaches may increase onset and decrease remission. Exposure to chemical emissions from indoor materials after first year of life may increase onset. Prenatal exposure to farm environment and large family size could be protective.

Additional file 1.

The long-term effects of ambient PM2.5 and chemical constituents on childhood pneumonia were still unknown. A cross-sectional study was conducted in 30,315 children in the China Children, Homes, Health (CCHH) project, involving 205 preschools in six cities in China, to investigate the long-term effects of PM2.5 constituents on lifetime-ever diagnosed pneumonia. Information on the lifetime-ever pneumonia and demographics were collected by validated questionnaires. The lifetime annual average ambient PM2.5, ozone and five main PM2.5 constituents, including SO42-, NO3-, NH4+, organic matter (OM) and black carbon (BC), were estimated according to preschool addresses by a combination of satellite remote sensing, chemical transport modeling and ground-based monitors. The prevalence of lifetime-ever diagnosed pneumonia was 34.5% across six cities and differed significantly among cities (p = 0.004). The two-level logistic regression models showed that the adjusted odds ratio for PM2.5 (per 10 µg/m3) and its constituents (per 1 µg/m3)-SO42-, NO3-, NH4+, and OM were 1.12 (95% CI:1.07-1.18), 1.02 (1.00-1.04), 1.06 (1.04-1.09), 1.05 (1.03-1.07) and 1.09 (1.06-1.12), respectively. Children in urban area, aged

Background: youthful blood environment was shown to decelerate the aging process of kidney and to attenuate senile renal fibrosis in a young-old parabiotic animal model; in addition, we identified a stem cell factor (SCF) that is closely linked with the process. To further investigate the effect of youthful blood environment on renal interstitial fibrosis and the underlying mechanisms, we bred SCF receptor c-Kit gene loss-of-function Wps/Wps mice and established a combination mice model that was subjected to unilateral ureteral obstructive (UUO) and parabiotic surgeries.Methods: Parabiotic mice were divided into isochronic parabiotic (young-young, Y-IP and old-old, O-IP) and heterochronic parabiotic (young-old, HP) groups. UUO surgery was performed in one of the parabiotic pairs in the IP group (Y-IPuuo and O-IPuuo) and in the elderly mice in the HP group (O-HPuuo). In order to study the role of SCF/c-kit on renal interstitial fibrosis, UUO surgery was performed in wildtype (WT) and Wps/Wps mice. Results: Fourteen days after UUO surgery, the kidney interstitial fibrosis area, kidney function, and the expressions of SCF/c-Kit, pNF-κB, and fibrosis-related proteins in the O-HPuuo group were significantly lower than those in the Ouuo and O-IPuuo groups. Compared with wildtype UUO mice, the expressions of pNF-κB and fibrosis-related proteins, kidney interstitial fibrosis area, and the kidney function were all significantly decreased in Wps/Wps UUO mice.Conclusions: Youthful blood environment downregulated the expressions of SCF/c-Kit in elderly UUO mice, and ameliorated UUO-induced kidney fibrosis and function loss, which may be mediated via the NF-κB pathway.

BackgroundOur previous study showed that guanine nucleotide exchange factor T (GEFT) was highly expressed in colorectal cancer (CRC) tissues and CRC patients with high GEFT expression had a poor prognosis, and suggested the close link of GEFT expression and CRC tumorigenesis/metastasis. In this text, the roles and upstream regulatory mechanisms of GEFT in the development and progression of CRC were further investigated.MethodsExpression levels of GEFT mRNA and LINC00355 was measured by RT-qPCR assay. Protein levels of lin-28 homologue A (LIN28A) and GEFT were determined by western blot assay. Cell proliferative, migratory, and invasive capacities were assessed by CCK-8, Transwell migration and invasion assays, respectively. The effect of GEFT knockdown on CRC tumorigenesis was examined by mouse xenograft experiments in vivo. GEFT mRNA stability was examined by actinomycin D assay. The relationships of LINC000355, LIN28A, and GEFT were explored by RNA pull down and RIP assays.ResultsGEFT was highly expressed in CRC tissues and cell lines. GEFT knockdown inhibited CRC cell proliferation, migration, and invasion, and hindered CRC xenograft tumor growth. GEFT overexpression alleviated the detrimental effects of LINC00355 loss on CRC cell proliferation, migration, and invasion. LINC00355 promoted GEFT expression and enhanced GEFT mRNA stability via LIN28A. LIN28A knockdown weakened the promotive effect of LINC00355 on CRC cell proliferation, migration, and invasion.ConclusionLINC00355 facilitated CRC tumorigenesis and progression by increasing GEFT expression via LIN28A, deepening our understanding on roles and upstream regulatory mechanisms of GEFT in CRC development and progression.

Given a large fraction of people's exposure to urban PM

Highlights • Combine the Wells-Riley model with Spatial Flow Impact Factor to obtain the spatial distribution of infection risk. • Determine the optimal distribution of people and/or facilities in the confined space through anti-problem approach. • Provide an inspiration to the simultaneous optimization of built environments that affect infection risk., The ongoing COVID-19 epidemic has spread worldwide since December 2019. Effective use of engineering controls can prevent its spread and thereby reduce its impact. As airborne transmission is an important mode of infectious respiratory disease transmission, mathematical models of airborne infection are needed to develop effective engineering control. We developed a new approach to obtain the spatial distribution for the probability of infection (PI) by combining the spatial flow impact factor (SFIF) method with the Wells-Riley model. Our method can be combined with the anti-problem approach, in order to determine the optimized arrangement of people and/or air purifiers in a confined space beyond the ability of previous methods. This method was validated by a CFD-integrated method, and an illustrative example is presented. We think our method can be helpful in controlling infection risk and making the best use of the space and equipment in built environments, which is important for preventing the spread of COVID-19 and other infectious respiratory diseases, and promoting the development of sustainable cities and society.

This paper presents a field experimental study of several participants’ evacuation behaviour in fire-induced smoke in a bidirectional six-lane, urban tunnel with natural ventilation. Ceiling openings with vertical shafts are equipped as natural ventilation and provide a large amount of sunlight into the tunnel in the daytime, increasing the illuminance in the tunnel and assisting evacuation in fire emergency. In this study, route choice, movement time, physical condition and reaction to technical installations were recorded and discussed to evaluate evacuees’ performance. Human factors including pedestrians’ gender, age and emotional state were taken into consideration. Besides, the characteristic of ceiling openings and its impact on human evacuation and technical systems settings are analysed. The results of the experiment and analysis suggest natural ventilation has a positive impact on evacuation. This study also leads to guidance on evacuation strategies in tunnels with natural ventilation and puts forward suggestions regarding to technical installations in the tunnel, such as way-finding signs and continuous light.

The long-term effects of ambient PM