Albumin (ALB) and protein disulfide isomerase family A member 4 (PDIA4) are novel markers to predict sperm freezability of Erhualian boar.

The frozen semen of Erhualian pig can promote the continuous improvement of commercial pigs, but currently, frozen semen fails to satisfy the practical application requirement. Oxidative damage is one of the crucial factors affecting the quality of frozen semen; besides, there are individual differences in boar sperm freezability. Based on the previous analysis of the proteomic differences of Erhualian boar sperm with different freezability, two differentially abundant proteins (DAPs) in boar sperm, albumin (ALB) and protein disulfide isomerase family A member 4 (PDIA4), were selected as the research objects in the current study. It is assumed that redox-related proteins ALB and PDIA4 can be used as markers to predict Erhualian boar sperm freezability. We cryopreserved the semen of 14 Erhualian boars. According to the difference of frozen semen quality, boars with good and poor freezability ejaculates (GFE and PFE, n = 3) were selected respectively. The relative contents of ALB and PDIA4 in GFE and PFE were analyzed by Western blot, and the localization patterns of ALB and PDIA4 in pre-frozen and frozen-thawed sperm were detected by immunofluorescence. The results showed that the abundances of ALB and PDIA4 in GFE were significantly higher than PFE, and there was a significant correlation between the relative contents of ALB and PDIA4 and frozen-thawed sperm quality parameters. Additionally, the freezing process had no effect on the localization patterns of ALB and PDIA4 in spermatozoa. In conclusion, these results suggest that ALB and PDIA4 are related to boar sperm cryotolerance and may be used as novel freezability markers.

[Relationship between sugary food intake and myopia in 11-14 years old Chinese children in 2019-2021].

OBJECTIVE: To investigate the relationship between the intake of sugary foods and the occurrence and development of myopia in children aged 11-14 in China. METHODS: In the 28 urban and rural survey sites in 14 provinces that implemented the "China Children's Nutrition and Health System Survey and Application for 0-18 Years Old" project, a multi-stage stratified random cluster sampling method was adopted, and finally 12 397 adolescent children aged 11 to 14 were selected in the analysis. Demographic characteristics, myopia information and the intake of sugary food(cakes, preserved fruits, candies, chocolates and ice cream) were collected through questionnaires. Multifactor Logistic regression was used to analyze the relationship between sugary food intake and myopia in children. RESULTS: The median daily intake of sugary foods(cakes, preserved fruits, candies, chocolates and ice cream)of 11-14 year old boys and girls in China was 11.4 g and 11.2 g respectively, 33.9% of boys and 34.2% of girls consumed ≥22 g of sugary food every day. The myopia rates of boys with intakes of <2 g, 2-21 g and ≥22 g were 36.0%, 39.2% and 41.6%, and girls' myopia rates were 45.9%, 51.8% and 55.1%. The result of Logistic regression analysis showed that after controlling for confounding factors such as age, gender, region, weekly high-intensity physical activity time, daily screen time, daily sleep time and daily intake of sugary beverages, compared with boys whose daily intake of sugary food was less than 2 g, the risk of myopia for boys whose daily intake of sugary food reached 2-21 g and ≥22 g was 1.18 and 1.23 times, for girls whose daily intake was less than 2 g, the risk of myopia was 1.27 times and 1.38 times for girls whose intake reached 2-21 g and ≥22 g(P<0.05). No matter whether confounding factors were controlled or not, there was no correlation between the intake of sugary foods and the degree of myopia(P>0.05). CONCLUSION: The consumption of sugary food such as cakes, preserved fruits, candies, chocolates and ice cream among children aged 11 to 14 in China is common, and there is a certain degree of positive correlation with the prevalence of myopia, but no correlation is observed with the degree of myopia.

An exploratory cross-sectional study on the impact of education on perception of stigma by Chinese patients with schizophrenia.

BACKGROUND: Stigma is a major issue across various society and cultures, and few studies focus on the perception of stigma by Chinese patients with schizophrenia. In the current cross-sectional study, we sought to assess the extent of internalized stigma among outpatients with schizophrenia in China and to investigate whether education level correlated with the experience of stigma. METHODS: Outpatients with schizophrenia were evaluated using the brief psychosis rating scale (BPRS), the positive and negative syndrome scale (PANSS), the clinical global impression-severity of illness (CGI-SI) scale and the Stigma Scale for Mental Illness (SSMI 2C). Patients were categorized into the high education and low education group according to their educational levels. RESULTS: One hundred thirty-three subjects were included in the study. Their mean course of illness was 4.32 ± 6.14 years (range, 1 month to 15 years). Their mean BPRS score was 19.87 ± 5.46, their mean PANSS score was 44.11 ± 13.1, and their mean CGI-SI score was 2.22 ± 0.81. In addition, the mean SSMI 2C score of the high education group (7.15 ± 0.98) was markedly higher than that of the low education group (5.75 ± 0.79, P < 0.05). The mean domain I score of the high education group (2.30 ± 0.76) was comparable to that of the low education group (2.07 ± 0.78, P > 0.05). The mean domain II score of the high education group (2.42 ± 0.96) was markedly higher than that of the low education group (2.01 ± 0.79, P < 0.05). Moreover, the mean domain III score of the high education group (2.43 ± 0.79) was significantly higher than that of the low education group (1.67 ± 0.77, P < 0.05). CONCLUSIONS: Education level impacts on the perception of stigma by patients with schizophrenia and more psycho-education should be done to improve patients' knowledge about schizophrenia.

Efficacy of repetitive transcranial magnetic stimulation (rTMS) on negative symptoms and cognitive functioning in schizophrenia: An umbrella review of systematic reviews and meta-analyses.

Negative symptoms and cognitive dysfunction are core characteristics of schizophrenia that profoundly impact daily function and quality of life. As a noninvasive brain stimulation, repetitive transcranial magnetic stimulation (rTMS) has been proposed as a relatively new treatment for ameliorating negative symptoms and cognitive dysfunction in schizophrenia. However, there is controversy over the treatment methods and efficacy. We aimed to provide a quantitative integration of the published evidence regarding the efficacy of rTMS and analyze the feasibility of rTMS for treating negative symptoms and cognitive dysfunction in schizophrenia. A total of twenty reviews were ultimately selected and divided into thirty-three latitudes. Twenty-six analyses showed that rTMS significantly decreased the negative symptom score, and seventeen analyses were performed. Six analyses showed that rTMS treatment can increase working memory scores, and two of them had significant effects. Two analyses from the same review showed that rTMS had a long-term significant effect on treating language function. Only one analysis showed that rTMS had a significant effect on treating executive function. The analyses showed that rTMS had no significant effect on attention function and processing speed. Most reviews indicate that rTMS has an effect on negative symptoms, executive function, working memory, and language function in patients with schizophrenia. Although the quality of evidence was not high, these results are still positive and worthwhile for further study.

Spatiotemporal pattern of coastal water pollution and its driving factors: implications for improving water environment along Hainan Island, China.

In the context of human activities and climate change, the gradual degradation of coastal water quality seriously threatens the balance of coastal and marine ecosystems. However, the spatiotemporal patterns of coastal water quality and its driving factors were still not well understood. Based on 31 water quality parameters from 2015 to 2020, a new approach of optimizing water quality index (WQI) model was proposed to quantitatively assess the spatial and temporal water quality along tropical Hainan Island, China. In addition, pollution sources were further identified by factor analysis and the effects of pollution source on water quality was finally quantitatively in our study. The results showed that the average water quality was moderate. Water quality at 86.36% of the monitoring stations was good while 13.53% of the monitoring stations has bad or very bad water quality. Besides, the coastal water quality had spatial and seasonal variation, along Hainan Island, China. The water quality at "bad" level was mainly appeared in the coastal waters along large cities (Haikou and Sanya) and some aquaculture regions. Seasonally, the average water quality in March, October and November was worse than in other months. Factor analysis revealed that water quality in this region was mostly affected by urbanization, planting and breeding factor, industrial factor, and they played the different role in different coastal zones. Waters at 10.23% of monitoring stations were at the greatest risk of deterioration due to severe pressure from environmental factors. Our study has significant important references for improving water quality and managing coastal water environment.

Spatiotemporal patterns of urban forest carbon sequestration capacity: Implications for urban CO2 emission mitigation during China's rapid urbanization.

Urban forests provide ecological functions and human well-being. However, spatiotemporal changes in urban forest carbon sequestration (CS) under rapid urbanization remain poorly understood. We established a model to predict the annual CS dynamics in urban forests based on plot-measured CS and Landsat images. Our results showed that the urban forest coverage in Changchun increased from 18.09 % to 24.01 % between 2000 and 2019, especially in the urban suburbs. However, urban forest patches became more fragmented and less connected, particularly in the urban center. The NDVI is better than other vegetation indices for mapping urban forest CS. We observed a gradual increase in urban forest CS capacity from 2000 to 2019, with higher CS capacity found in urban suburbs compared to urban centers. The class distribution of urban forest CS capacity was skewed toward low values (0-2 g·m-2·d-1), but this tendency diminished gradually. In 2000, the urban forest in Changchun offset approximately 2.11 % of carbon emissions but declined to 0.88 % by 2019 due to increased carbon emissions. Rapid urbanization was the main factor affecting CS, with impervious surface area accounting for 48.7 % of the variation. Urban landscape pattern indices also influenced the CS, with higher forest patch connectivity and lower patch density leading to greater CS capacity. Our study helps urban managers develop urban greening strategies for carbon neutrality and low-carbon city.

Rapid urbanization and meteorological changes are reshaping the urban vegetation pattern in urban core area: A national 315-city study in China.

Urban vegetation takes on the responsibility of improving the urban environment and human wellbeing. However, the changing pattern and its driving mechanism are still not well understood at the national scale, especially in China under nearly 20 years-long rapid urbanization. In this study, for urban core area in 315 cities, over 18,000 high-resolution remote sensing images across 18 years were used to detect the spatiotemporal changes of urban vegetation and furtherly explore the interaction and independence of rapid urbanization and meteorological change. We found that, urban vegetation coverage decreased from 12.23 % to 5.91 % (-0.35 % per year) in 2003 to 2020. Urban vegetation per capita presented a steeper decline by 68 % (-0.51 m2 per capita per year) from 18.94 m2 in 2003 to 9.83 m2 in 2020. Spatially, the northwest and central-south zone decreased faster at the regional scale, and small cities contribute the higher decreasing rate. From 2003 to 2020, urbanization is the significant negative factor which contribute to 29.6 % of the reduction, and the meteorological factors do not affect urban vegetation change. Also, we found that the temporal pattern of urban vegetation change could be separated into two stages, including a rapid decline stage (2009-2020) and a progressively declining stage (2003-2008), each has its own driving mechanism. From 2003 to 2008, the decline in urban vegetation had insignificant relationship with meteorological changes and rapid urbanization. However, from 2009 to 2020, urbanization became the most critical factor to affect the urban vegetation, the contribution of urbanization rises to 30.3 %, meteorological factors contribute 14.3 % to the variation (r2 = 0.52). A growing crisis awareness of the rapid decline (especially in 2009 to 2020) of urban vegetation should return to the public scene, and these findings may provide some essential suggestions for securing this urban ecological barrier.

A biomimetic peptide-drug supramolecular hydrogel as eyedrops enables controlled release of ophthalmic drugs.

The rapid clearance of instilled drugs from the ocular surface due to tear flushing and excretion results in low drug bioavailability, necessitating the development of new drug delivery routes. Here, we generated an antibiotic hydrogel eye drop that can extend the pre-corneal retention of a drug after topical instillation to address the risk of side effects (e.g., irritation and inhibition of enzymes), resulting from frequent and high-dosage administrations of antibiotics used to obtain the desired therapeutic drug concentration. The covalent conjugation of small peptides to antibiotics (e.g., chloramphenicol) first endows the self-assembly ability of peptide-drug conjugate to generate supramolecular hydrogels. Moreover, the further addition of calcium ions, which are also widely present in endogenous tears, tunes the elasticity of supramolecular hydrogels, making them ideal for ocular drug delivery. The in vitro assay revealed that the supramolecular hydrogels exhibited potent inhibitory activities against both gram-negative (e.g., Escherichia coli) and gram-positive (e.g., Staphylococcus aureus) bacteria, whereas they were innocuous toward human corneal epithelial cells. Moreover, the in vivo experiment showed that the supramolecular hydrogels remarkably increased pre-corneal retention without ocular irritation, thereby showing appreciable therapeutic efficacy for treating bacterial keratitis. This work, as a biomimetic design of antibiotic eye drops in the ocular microenvironment, addresses the current issues of ocular drug delivery in the clinic and further provides approaches to improve the bioavailability of drugs, which may eventually open new directions to resolve the difficulty of ocular drug delivery. STATEMENT OF SIGNIFICANCE: Herein, we present a biomimetic design for antibiotic hydrogel eye drops mediated by calcium ions (Ca2+) in the ocular microenvironment, which can extend the pre-corneal retention of antibiotics after topical instillation. The mediation of Ca2+ which is widely present in endogenous tears, tunes the elasticity of hydrogels, making them ideal for ocular drug delivery. Since increasing the ocular retention of antibiotic eye drops enhances its action and reduces its adverse effects, this work may lead to an approach of peptide-drug-based supramolecular hydrogel for ocular drug delivery in clinics to combat ocular bacterial infections.

Highly stable fibronectin-mimetic-peptide-based supramolecular hydrogel to accelerate corneal wound healing.

Without timely treatment, poor wound healing in corneal injuries can seriously impair vision and lead to blindness. Thus, it is vital to develop a therapeutic strategy to accelerate corneal re-epithelialization. The conjugation of self-assembled motifs with a fibronectin-mimetic peptide sequence (PHSRN) drastically improves the chemical stability of PHSRN against protease hydrolysis and minimally affects its biological activity to promote the migration of corneal epithelial cells. The optimized Nap-FFPHSRN self-assembled into bioactive supramolecular hydrogels increases cell motility by remolding F-actin and boosts the tight junction of the corneal epithelium by increasing the expression of zonula occludens-1 (ZO-1). An in vivo experiment showed that a Nap-FFPHSRN hydrogel provided extended precorneal retention with good ocular tolerance after topical instillation. An animal model of corneal scrape showed that a single daily dose of Nap-FFPHSRN hydrogel had a superior therapeutic effect in facilitating corneal re-epithelialization with complete morphological and architectural recovery. With a rational approach to mimic bioactive proteins, this study presents a new strategy to demonstrate the potential of peptide-based supramolecular hydrogels for use in clinical treatment of corneal injury. STATEMENT OF SIGNIFICANCE: Here we systematically investigate the self-assembly behavior and chemical stability of designed peptide amphiphiles (Nap-FPHRSN, Nap-FFPHSRN and Nap-FFFPHSRN). The introduction of self-assembled motifs (Nap-F, Nap-FF and Nap-FFF) drastically enhances the chemical stability of fibronectin-mimetic peptide (PHSRN). Moreover, topical instillation of Nap-FFPHSRN hydrogel once daily, exhibits a better in vivo effect than PHSRN and the same in vivo effect as fibronectin, both of which are instilled three times daily, for promoting full morphological and architectural recovery after corneal re-epithelialization. As a rational design of conjugating bioactive peptides with self-assembled motifs to mimic bioactive proteins, this work may lead to a new approach that improves the in vivo therapeutic effect for treating corneal injury in clinic settings.

Supramolecular nanofiber of indomethacin derivative confers highly cyclooxygenase-2 (COX-2) selectivity and boosts anti-inflammatory efficacy.

Herein, we report a facile method for converting carboxylate-containing indomethacin (Idm) into a cyclooxygenase-2 (COX-2) selective inhibitor via the amidation of an unnatural peptide sequence (Nal-Nal-Asp). The resulting indomethacin amides (i.e., Idm-Nal-Nal-Asp) have high selectivity for COX-2, and can self-assemble into a one-component supramolecular hydrogel that acts as a 'self-delivery' system for boosting anti-inflammatory efficacy. Self-assembled Idm-Nal-Nal-Asp hydrogel robustly inhibits COX-2 expression in lipopolysaccharide (LPS)-activated Raw 264.7 macrophages while also exhibits superior anti-inflammatory and antioxidant activities via reactive oxygen species (ROS)-related NF-κB and Nrf2/HO-1 pathways. Moreover, a rabbit model of endotoxin-induced uveitis (EIU) reveals that the Idm-Nal-Nal-Asp hydrogel outperforms clinically used 0.1 wt% diclofenac sodium eye drops in terms of in vivo anti-inflammatory efficacy via topical instillation route. As a rational approach to designing and applying COX-2 selective inhibitors, this work presents a simple method for converting non-selective nonsteriodal anti-inflammatory drugs (NSAIDs) into highly selective COX-2 inhibitors that can self-assemble into supramolecular hydrogel for anti-inflammation applications.

Dietary Patterns and Associations with Myopia in Chinese Children.

Dietary shifts in populations undergoing rapid economic transitions have been proposed as partly contributing toward the rapid intergenerational rise in myopia prevalence; however, empirical evidence of the effect of dietary factors on myopia is limited. This study investigated the association between dietary factors and incident myopia in Chinese children aged 10-11 years. We evaluated dietary habits using a 72-item food frequency questionnaire (FFQ) among 7423 children. Myopic status was assessed using the "General Personal Information Questionnaire". Principal component analysis was used to extract dietary patterns and investigate their association with myopia. After adjusting for potential confounders, participants with the highest adherence to dietary pattern A (95% confidence interval (CI): 0.66-0.92, p for trend = 0.007) and dietary pattern C (95% CI: 0.58-0.80, p for trend < 0.001) had a lower risk of myopia than participants with the least adherence. Both of these dietary patterns are characterized by high consumption of meats, aquatic product, dairy and its products, eggs, legumes, vegetables, fruits, grains, and potatoes. Our findings suggest that other environmental factors, such as those related to the dietary environment, may contribute to the development of myopia. These findings can serve as a reference for diet-related primary prevention of myopia.

Decrease in the residents' accessibility of summer cooling services due to green space loss in Chinese cities.

Urban green spaces (UGSs) reduce the surrounding temperature and create cooling areas as a buffer between people and high temperatures, thus helping residents adapt to the warming climate. However, the accessibility of UGS cooling services to the residents of cities remains largely unknown, which hinders decision-making regarding the formulation of climate adaptation and urban greening schemes. In the present study, we estimated the number of residents who accessed UGSs for cooling by analyzing the annual changes in such cooling areas during summer across 315 Chinese cities from 2003 to 2015. Approximately 93.3% of the cities showed significant decreasing trends (p < 0.05) of the total UGS area; as such the UGS coverage dropped from 12.23 ± 0.32% in 2003 to 7.69 ± 0.22% in 2015. Consequently, with the prevalent loss of UGS, the coverage of cooling spaces decreased from 32.55 ± 0.76% in 2003 to 24.39 ± 0.60% in 2015. This has formed a spatial mismatch between the growing urban population and the remaining UGSs. Accordingly, the number of residents of areas outside these cooling spaces increased by 4.23 million per year. In particular, the shortage of cooling services was more significant in cities with < 20,000 USD gross domestic product per capita and < 5 million residents than in the rest of the cities. To minimize the adverse impacts of increasing temperatures, focused greening plans are warranted, specifically in underdeveloped cities.

Soil microbial abundance was more affected by soil depth than the altitude in peatlands.

Soil microbial abundance is a key factor to predict soil organic carbon dynamics in peatlands. However, little is known about the effects of altitude and soil depth and their interaction on soil microbial abundance in peatlands. In this study, we measured the microbial abundance and soil physicochemical properties at different soil depths (0-30 cm) in peatlands along an altitudinal gradient (from 200 to 1,500 m) on Changbai Mountain, China. The effect of soil depth on soil microbial abundance was stronger than the altitude. The total microbial abundance and different microbial groups showed the same trend along the soil depth and altitudinal gradients, respectively. Microbial abundance in soil layer of 5-10 cm was the highest and then decreased with soil depth; microbial abundance at the altitude of 500-800 m was the highest. Abiotic and biotic factors together drove the change in microbial abundance. Physical variables (soil water content and pH) and microbial co-occurrence network had negative effects on microbial abundance, and nutrient variables (total nitrogen and total phosphorus) had positive effects on microbial abundance. Our results demonstrated that soil depth had more effects on peatland microbial abundance than altitude. Soil environmental change with peat depth may lead to the microorganisms receiving more disturbances in future climate change.

Effect of School-Based Nutrition and Health Education for Rural Chinese Children.

The nutritional status of rural Chinese children has improved in recent years, but their nutritional knowledge is still relatively lacking. School-based nutrition and health education was conducted for children in three counties of China from 2018 to 2020. The students in the intervention schools were given two-year nutrition and health education courses, while the control schools did not receive any intervention. Students' nutrition knowledge, dietary intake, and dietary behaviors were collected using a questionnaire, and height and weight were measured uniformly. The nutrition knowledge score in the intervention group was increased by 1.01 and 0.64 points in the first and second years. A multilevel model was used to evaluate the intervention effects. Statistically significant interactions between groups and time were observed in nutrition knowledge, the frequency of eating breakfast, and dietary intake, including meat, eggs, milk, and vegetables (p < 0.05), but not in nutritional status. Therefore, the supplementation of school-based nutrition and health education had a positive impact on the nutrition knowledge and dietary intake of rural Chinese children.

Study on the relationship among dose, concentration and clinical response in Chinese schizophrenic patients treated with Amisulpride.

OBJECTIVE: To provide therapeutic window of amisulpride dose and serum concentration. METHODS: 194 schizophrenics were assessed with PANSS. The concentration of Amisulpride in blood was tested. And relationship with concentration was analyzed. RESULTS: The dose of amisulpride was 100mg∼1200 mg/d(555+/-218), plasma concentration was 20∼1280 ng/mL(349+/-223) and C/D ratio was 0.07∼1.65 (0.63+/-0.34). The correlation of dose and concentration was significantly correlated (r = 0.55; P < 0.05).It was found that concentration(P < 0.001), C/D ratio(r = 0.383, P < 0.001), rather than dose (-0.042,p > 0.05) related to age significantly.It was found no differences in dose(p > 0.05), concentration (p > 0.05) and C/D ratio(p > 0.05) between male and female patients. The change ratio of positive symptom was 10 %∼90 %, negative symptom was 5∼80 %, general symptoms was 5∼90 %, PANSS was 5∼90 %.The correlation between change ratio of positive symptom, general symptom and PANSS and dose, concentration were significant(P < 0.01), but not related with the change ratio of negative symptom(p>0.05).The both dose and concentration of amisulpride were higher significantly in effective group than that in ineffective group according to change ratio of positive symptom, negative symptom, general symptom and PANSS(P < 0.01). CONCLUSION: The correlation of dose and concentration of amisulpride was significantly correlated. The recommended range 457∼637 ng/mL was suggested as average therapeutic window.

A Placebo-Controlled Study on the Treatment of Metabolic Syndrome of Qi Stagnation and Dampness Obstruction Related to Atypical Antipsychotics with Traditional Chinese Medicine (TCM).

METHODS: 154 schizophrenics who met both the diagnostic criteria of metabolic syndrome and qi stagnation and dampness obstruction syndrome were randomly divided into 2 : 1 groups. The PANSS and Tess were assessed before treatment and at the end of first month, second month, and third month after treatment; blood pressure, weight, waist circumference, hip circumference, blood glucose, glycosylated hemoglobin, high-density lipoprotein, low-density lipoprotein, triglyceride, and cholesterol were also measured at the same four time points. On the basis of continuous antipsychotic treatment, the study group took Liuyu decoction, and the control group took placebo. RESULTS: Of the 154 cases, 102 were in the study group and 52 in the control group. Before and after treatment, there was a slight increase but no significant difference in blood pressure, blood sugar, glycosylated hemoglobin, cholesterol, TG, DHL, and LHL in two groups (P > 0.05) and also between the two groups (P > 0.05). The body weight, waist circumference, hip circumference, and BMI in the study group decreased, while that in the control group increased from the dividing group to the end of study. At the end of the third month, there was a significant difference in the body weight, waist circumference, hip circumference, and BMI between the two groups (P < 0.05). Before and after treatment, there was a significant difference in positive symptoms, negative symptoms, general symptoms, and PANSS in two groups, respectively (P < 0.05). The negative symptoms, general symptoms, PANSS, and TESS in the study group were lighter than that in the control group after treatment. CONCLUSION: Liuyu decoction is not only beneficial to the treatment in body constitution of metabolic syndrome in qi stagnation and dampness obstruction but also beneficial to the improvement of such patients' mental symptoms and side effects.

Enhanced Storage Stability of Different Polymer Modified Asphalt Binders through Nano-montmorillonite Modification.

The storage stability concern, caused by phase separation for the density difference between polymers and asphalt fractions, has limited the widespread application of polymer modified asphalt (PMA). Therefore, this study aims to improve the storage concern of PMA by incorporating nano-montmorillonite. To this end, different nano-montmorillonites were incorporated to three PMAs modified with three typical asphalt modifiers, i.e., crumb rubber (CRM), styrene-butadiene-rubber (SBR) and styrene-butadiene-styrene (SBS). A series of laboratory tests were performed to evaluate the storage stability and rheological properties of PMA binders with nano-montmorillonite. As a consequence, the incorporation of nano-montmorillonite exhibited a remarkable effect on enhancing the storage stability of the CRM modified binder, but limited positive effects for the SBR and SBS modified binders. The layered nano-montmorillonite transformed to intercalated or exfoliated structures after interaction with asphalt fractions, providing superior storage stability. Among selected nano-montmorillonites, the pure montmorillonite with Hydroxyl organic ammonium performed the best on enhancing storage stability of PMA. This paper suggests that nano-montmorillonite is a promising modifier to alleviate the storage stability concern for asphalt with polymer modifiers.

Spatiotemporal patterns of urban thermal environment and comfort across 180 cities in summer under China's rapid urbanization.

BACKGROUND: China is considered as the largest and most rapidly urbanizing nation in the world. However, possible changes of urban thermal environment and comfort under the rapid urbanization in China still remain poorly understood at a national scale. METHODS: Based on the data collected from 180 cities in 1990, 2005, and 2015 in China, the spatiotemporal patterns of urban thermal environment and comfort in summer and their relationships with urbanization variables were investigated in this study. RESULTS: Our results indicate that urban thermal environment has changed greatly during the 25 years. Furthermore, the changes of urban climate in different regions are inconsistent. The Physiological Equivalent Temperature (PET) at most cities (81%) in China increased from 1990 to 2015, which suggested that urban thermal comfort in China was also deteriorating during the 25 years. However, while the PET of some cities in China began to decrease from 2005 to 2015, there were still 33% of cities that had positive trends,which mainly located in North region. Urbanization resulted in a significant influence on urban climate. Compared to southern cities, northern cities were more sensitive to urbanization impact. The most important contribution to increasing of PET for urbanization variables is gross domestic product, followed by urban population. The analysis results reveal changing patterns of urban thermal comfort in China during summer season. It can help urban government and managers improve urban thermal environment and comfort.

Long-term dynamics of urban thermal comfort in China's four major capital cities across different climate zones.

China has experienced intensive urbanization over the past decades. However, it is still unclear about the influence of urbanization on urban thermal comfort and how the effect varies with climate condition. Based on long-term daily meteorological data from 1990 to 2015 in four Chinese cities undergoing rapid urbanization, our study tried to detect the long-term dynamics of summer urban thermal comfort across different climate zones and analyze their relationships with urbanization. Our results showed that urbanization can increase urban temperature and decrease relative humidity and wind velocity. Urban thermal comfort and discomfort days also changed greatly, especially in Harbin, Northeast China from 1990 to 2015. However, such changes for different cities across different climate zones are inconsistent. Results also showed that urbanization especially for social economic activities can have a significant influence on the physiological Equivalent Temperature (PET). Compared with southern cities, the PET in northern cities such as Harbin and Changchun in this study is more sensitive to urbanization. These results reveal that the changing patterns of urban thermal comfort in Chinese cities under rapid urbanization, and help government take some effective measures to improve urban thermal environment.

Recycled Heavy Bio Oil as Performance Enhancer for Rubberized Bituminous Binders.

Asphalt rubber (AR) is a sustainable paving material with merits including waste tire consumption, low traffic noise, and enhanced mechanical performance. However, the poor workability and storage stability limited its further application. This study attempted to alleviate these two concerns of AR simultaneously by incorporating heavy bio oil (HBO). To achieve this goal, bio-AR binders with three different mixing sequences were prepared. A series of rheological and chemical tests were conducted. Test results prove that the bio-AR binders exhibited superior rutting and fatigue resistance compared to AR binder. The viscosity values of bio-ARs were closed to AR modified with commercial warm mix additive, which indicates enhancement in workability. Due to the relatively high density of HBO, the density difference between the asphalt liquid phase and crumb rubber in the bio-AR system narrowed, which brought improved storage stability. Among bio-ARs prepared with different mixing sequences, the direct mixing one (ARB) had the most satisfied overall performance. The early incorporation of HBO had limited negative influence on binder performance, but allowed for more energy saving during the bio-AR binder production. Future study will be conducted on performance of bio-AR mixtures and quantitative estimation of its energy saving during the blending and compacting process.