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This case study proposed a novel electro-osmosis PRD vacuum preloading method to solve dredging sludge treatment issues: difficulty in draining from soil showing large volume, non-uniform settlement, and low strength. To verify the effectiveness of the new method, four kinds of physical model tests integrating particle image velocimetry (PIV) technique of traditional vacuum preloading (VP), prefabricated radiant drain vacuum preloading (PRD-VP), electro-osmotic vacuum preloading (EO-VP), and EO-PRD-VP methods are conducted. The water discharge, average surface settlement, pore water pressure, water content, and undrained shear strength after treatment, clogging range, relationship between clogging range and water discharge rate, and relationship between clogging range and average surface settlement are investigated. For those model tests, it is demonstrated that EO-PRD-VP method has the best advantage in volume reduction, uniform settlement, and strength improvement. Water discharge is enlarged by 13–33%. The differential settlement can reach 2.3 cm, decreased by 28–56%. The undrained shear strength can reach 12 kPa, increased by 1–2 times. In addition, the clogging range development is described, for the given water discharge rate and average surface settlement, clogging range of EO-PRD-VP method is the minimum. The empirical equations between clogging range and water discharge rate, clogging range, and average surface settlement are established to predict the clogging range, which can lay the foundation for developing the consolidation theory of EO-PRD-VP method. [ABSTRACT FROM AUTHOR]

This study observed the effects of the Clark comfortable nursing approach on self-care ability, self-burden, treatment adherence, quality of life, and complications in hemodialysis patients with end stage renal failure (ESRF). Eighty-two patients with ESRF receiving hemodialysis treatment were included and allocated into control and intervention groups. The control group received conventional nursing care, while the intervention group received the Clark comfortable nursing approach. The self-care ability, self-burden, treatment adherence, quality of life scores before and after the nursing intervention, and the occurrence of complications in both groups were compared. After the intervention, the intervention group showed higher scores in each dimension and the total score of the Exercise of Self-Care Agency Scale compared to the control group. Both groups exhibited improvements in various scores and total scores; however, the intervention group had lower scores overall than the control group. Additionally, the intervention group had higher scores in diet, water intake, medication, and dialysis regimen. Additionally, both groups had significantly higher scores in all dimensions of the quality-of-life scale post-intervention, with the intervention group demonstrating markedly higher scores in all dimensions. The total incidence of complications in the intervention group was 9.76%, which was lower than the 29.27% observed in the control group. The Clark comfortable nursing approach applied to hemodialysis patients with ESRF can enhance self-care ability, improve quality of life, increase treatment adherence, and reduce the incidence of hemodialysis-related complications. This model is worthy of clinical promotion. [ABSTRACT FROM AUTHOR]

Objective To investigate the oral health behavior of urban and rural students in the 12~15 year age group in Guangdong Province, aiming to provide informational support for adolescent oral health care. Methods A multistage stratified sampling method with equal capacity and simple random sampling was applied to obtain representative samples. A total of 7 680 students aged 12 to 15 were selected from Guangdong Province, with 1 920 in each age group of 12, 13, 14 and 15 years; half were male and half were female, and half were from urban areas and half were from rural areas. According to the Fourth National Oral Health Epidemiology Questionnaire Survey Program, a standard questionnaire was designed to conduct on-the-spot investigations on sugar intake, brushing, dental floss usage, fluoride toothpaste usage. Results ① Eating before a meal and before bed: the proportion of sweet snacks, sweet drinks and sugary drinks consumed ≥2 times/day was higher in the rural group than in the urban group (P < 0.001), with only sugary drinks consumed significantly differently by age (P < 0.001). ② The rural group had a significantly lower proportion of brushing ≥ 2 times/day, flossing habits and fluoride toothpaste habits than the urban group (P < 0.001), whereas only fluoride toothpaste habits were significantly different across age groups (P < 0.001). Conclusions Among the students aged 12 to 15 in Guangdong Province, the rural group had a higher proportion of consuming desserts, sweet drinks and sweetened drinks. The proportion of brushing ≥ 2 times/day was lower, and the usage rate of floss and fluoride toothpaste was lower.

Objective To understand the level and current status of oral health knowledge among people aged 35⁃44 years in Guangdong Province and to provide a reference for oral health education in Guangdong Province. Methods An equal⁃sized, stratified, multistage, random sampling design was applied to obtain representative sample groups consisting of 288 Guangdong residents aged 35⁃44 years in four urban areas and four rural areas with a gender ratio of one to one. According to the Guideline of the 4th National Oral Health Survey, a questionnaire survey was conducted, and a statistical analysis of the questionnaire responses related to oral health knowledge was performed. Results In total, 288 people participated in the survey, of which 95.8 percent were aware that“Oral health is very important to their own lives, and the prevention of oral diseases depends on themselves first” , 76.0% recognized that“Regular oral examination is very necessary” , and 66.7% disagreed that“Teeth were innate and had little to do with their own protection” . The percentages of participants that agreed with the statements“Eating sugar can cause dental caries” ,“Oral disease may affect general health” ,“Bacteria may cause dental caries”and“Bacteria may cause gum inflammation”were 87.2% , 84.7%, 80.9%, and 80.2%, respectively. However, the rates of awareness that teeth could be protected by fluoride and by pit and fissure sealant were only 36.8% and 18.8%, respectively. Conclusion General knowledge of oral health care was relatively high among adults aged 35 ⁃ 44 years in Guangdong Province, but knowledge of fluoride, pit and fissure sealing and caries prevention was relatively low. Oral health education should be continuously improved, especially regarding the popularization of oral health knowledge.

In order to analyze the thermal environment and its influence on workers’ thermal adaptation, a field study was conducted in a rubber factory during winter. Indoor and outdoor environmental parameters were measured and subjective questionnaire surveys were collected. The study was conducted from November to January the next year. During the survey, indoor temperature was in the range of 12.6 to 21.7°C and indoor air velocity ranged from 0.15 to 0.3 m/s. The clothing insulation during heating period was between 0.85-0.9 clo, while it was between 1.21-1.33 clo during pre-heating period. The estimated metabolic rate was around 2-2.2 met. Analysis showed that the thermal sensation vote (TSV) was higher than that predicted by PMV. The neutral temperature difference between TSV and PMV was 4.8°C. The thermal comfort and thermal adaptation of workers in winter were systematically analyzed and a thermal adaptive model was proposed. Basis on the adaptive model, the comfort temperature range of workers was suggested.

Local draft experiments were conducted to establish the overall thermal sensation prediction model under low pressure environment. Head, chest, hand, and ankle were exposed to local airflow under three pressure environments: 1 atm, 0.87 atm, and 0.74 atm, respectively. The skin temperature was measured and the subjective questionnaires were collected. The results showed that in cooler environment, the mean skin temperature decreased with the decrease of pressure, and people maybe more sensitive. When the environmental pressure decreased, the overall thermal sensation decreased correspondingly. Compared with the normal pressure condition, as the pressure decreased, the weight of local thermal sensation on overall thermal sensation changed a little. The weight of chest decreased while the weight of hands increased. When exposed to local draft, the four body parts showed similar influence on the overall thermal sensation under lower pressure conditions. Based on influence of pressure, temperature, and local draft speed, the overall thermal sensation prediction model for each body part was established respectively. The results indicated that the predicted values were highly correlated with the measured values. The models could be used to predict thermal sensation of people who are exposed to local draft in low pressure environment.

This study examines the public acceptance of platoon control for connected and automated vehicles (CAVs) and analyzes it from a sustainability perspective. A questionnaire survey was conducted targeting a diverse social group to collect data on public attitudes, acceptability, and factors related to the environment, social responsibility, personal economy, and behavior. Factor analysis was then performed to reduce these data into three factors: "attitudes and acceptance", "environment and social responsibility", and "personal economy and behavior". Further, multiple regression analysis was employed to investigate the relationship between these three factors and the willingness to accept platooning control, as well as the willingness to actively adopt it. The findings indicate that the "attitude and acceptance" factor significantly influences the public's acceptance of platoon control. Moreover, the "environment and social responsibility" and "personal economy and behavior" factors also have a certain influence on decision-making. This study not only contributes to understanding public attitudes towards CAVs' platoon control but also explores how to promote the development of sustainable intelligent transportation systems. By gaining a better understanding of public attitudes, policymakers and relevant stakeholders can take measures to enhance the acceptance of CAVs, thereby driving the sustainable development of transportation systems. [ABSTRACT FROM AUTHOR]

In a full-scale case study, the performance of two methods—the vacuum-surcharge preloading method (S-VP) and the air-booster vacuum preloading method (A-VP)—were compared in terms of the dredged soft soil ground of the Xiang'an International Airport pavement reinforcement project in Xiamen City, China. The pore water pressure dissipation, settlement, lateral displacement, and consolidation degree were measured in the zones reinforced using the two methods. The direct shear test and field vane shear test were conducted before and after improvement. The S-VP and A-VP methods were loaded for 308 and 228 days, respectively. The results show that both reinforcement methods significantly improved the shear strength and foundation bearing capacity of the soft soil ground. The S-VP method has about 30% higher final vane shear strength and more uniform settlement compared to the A-VP method. However, the dissipation value of the average pore water pressure and the maximum foundation settlement were 5.6% and 11% higher, respectively, in A-VP than in S-VP. Compared to the S-VP method, the A-VP method decreased the maximum lateral displacements by 15%–20%, and increased the maximum reinforcement depth by 11%. Finally, compared with the use of sand cushion and vacuum pump, the A-VP method was more economical in terms of cost and energy use. Land reclamation projects will produce a large area of ground composed of ultrasoft soil, which has very low strength and cannot be used for construction activities directly on such ground. For such ultrasoft soil ground, the vacuum preloading method is generally used to strengthen the ultrasoft soil. In this study, two different vacuum preloading methods [the vacuum-surcharge preloading method (S-VP) and the air-booster vacuum preloading method (A-VP)] were used to strengthen the ultrasoft soil, and the final reinforcement effect and cost of the two methods were compared. The results show that the final reinforcement effect of the A-VP method was close to that of the S-VP method. Furthermore, the A-VP method saved more than 3 million Chinese currency (CNY) and reduced the power consumption by 80% in this project. In addition, the implementation of the A-VP method does not require a large amount of sand that is difficult to obtain in coastal areas, which is good protection for the natural resources in coastal areas. Therefore, in the ultrasoft soil reinforcement project, the A-VP method is a method worth considering. [ABSTRACT FROM AUTHOR]

To investigate the effect of azimuthal anisotropy on frequency-domain marine controlled-source electromagnetic (CSEM) responses, an adaptive edge-based finite-element (FE) modeling algorithm is presented in this letter. The 3-D algorithm is capable of dealing with generally anisotropic conductive media. It is implemented on unstructured tetrahedral grids, which allow for complex model geometries. The accuracy of the FE solution is controlled through adaptive mesh refinement, which is performed iteratively until the solution converges to the desired accuracy tolerance. The algorithm is validated against the quasi-analytic solutions for a 1-D layered model with anisotropy. We then simulate the marine CSEM responses over a set of 3-D anisotropic models and illustrate that the azimuthal anisotropy has a considerable influence on both the inline and broadside marine CSEM responses but to different extents. [ABSTRACT FROM AUTHOR]

The lytic cold-active bacteriophage VSW-3, belonging to the Podoviridae family and infecting the host Pseudomonas fluorescens SW-3, was isolated from the Napahai plateau wetland in China. With the development of sequencing technology, the study of Pseudomonas genomic diversity has increased; however, knowledge of cold-active phages infecting Pseudomonas is limited. The newly sequenced phage VSW-3 was classified based on virion morphology by transmission electron microscope. Sequence analysis revealed that the genome size was 40,556 bp with an overall GC content of 57.54 % and 46 open reading frames. The genome was organized into several modules containing genes for packaging, structural proteins, replication/transcription, and phage lysis. The sequence contained 45 potential promoters, 3 transcription terminators, and yet no tRNAs. This is the first report of cold-active Pseudomonas fluorescens bacteriophage genome sequencing. [ABSTRACT FROM AUTHOR]

Lead halide perovskite micro-devices such as microplates and microwires have shown great potential in microlasers, especially in the “green gap” wavelength region of conventional semiconductors. However, the synthesized perovskite lasers are usually randomly distributed on the substrate, making their laser emissions hard to be collected and utilized. Here we demonstrate a simple way to efficiently couple perovskite microlasers into conventional single mode fibers. By attaching a perovskite microwire onto a tapered fiber via micromanipulation, we found that the emissions along the single mode fiber are more than an order of magnitude larger than the collected emission with a 40× objective lens (NA = 0.6). The detailed estimation shows that the experimentally measured collection efficiency at one end of the tapered fiber can be around 13–20%, which is good enough for practical applications. Our numerical calculations show that the collection is mainly induced by the diffraction at the end of the microwire instead of the evanescent coupling and the total coefficient at the two ends can be further improved by optimizing the tapered fiber and microwire. As the tapered fiber is drawn from a commercial single-mode fiber, this research clearly shows the potential of perovskite devices to be integrated with conventional fiber systems. [ABSTRACT FROM AUTHOR]

Solution‐processed lead halide perovskites have shown good applicability in both solar cells and microlasers. Very recently, the nonlinear properties of perovskites have attracted considerable research attention. Second harmonic generation and two‐photon absorption have been successfully demonstrated. However, perovskite devices based on these nonlinear properties, such as micro‐ and nanolasers have thus far not been fabricated. Here we demonstrate two‐photon pumped microlasers from CH3NH3PbBr3 perovskite microwires. These CH3NH3PbBr3 perovskite microwires are synthesized through a one‐step solution precipitation method and dispersed on a glass substrate. Under optical excitation at 800 nm, two‐photon pumped lasing action with periodic peaks is successfully observed at around 546 nm. The obtained quality (Q) factors of the two‐photon pumped microlasers are around 682, and the corresponding thresholds are about 674 µJ cm‐2. Both the Q factors and thresholds are comparable to conventional whispering‐gallery modes in two‐dimensional polygon microplates. This work is the first demonstration of two‐photon pumped microlasers in CH3NH3PbBr3 perovskite microwires. We believe our finding will significantly expand the application of perovskites in low‐cost nonlinear optical devices, such as optical limiters, optical switches, and biomedical imaging devices. [ABSTRACT FROM AUTHOR]

This study focuses on the effect of phase change cooling garment (PCCG) on thermal comfort of factory workers in hot indoor environment. Participants were asked to perform two physical activities: packing and standing. Physiological parameters (including heart rate, blood pressure, oxygen saturation, skin temperature and ear canal temperature) were measured and subjective questionnaires (involving overall and local thermal sensation, thermal comfort, thermal satisfaction, etc.) were collected. Cognitive ability tests were conducted. The results showed that the PCCG reduced the mean skin temperature and local skin temperature of the cooling parts effectively. The mean skin temperature decreased approximately 1 °C during packing, and 1.6 °C during standing, which indicated that the cooling effect declined with the increase of metabolic rate. For the other measured physiological parameters, the use of PCCG had little effect on them. Both the local and overall thermal sensation decreased significantly when using the PCCG, and the decrement also dropped as metabolic rate increased. Other subjective votes were also significantly improved. The working efficiency was increased by 19%. Most of the subjects had no cold stimuli sensation when put on the PCCG. The results of cognitive ability tests showed that, the use of PCCG had no effect on the task error rate, while the completion time was decreased. The reduction in mean skin temperature and thermal sensation was correlated in the two activities, separately. For workers exposed to hot environment, the PCCG improved their thermal comfort and working efficiency effectively, while the effectiveness was related to activity level. • Cooling garment improved workers' thermal comfort in hot indoor environment. • Reduction in thermal sensation was related to reduction of mean skin temperature. • Improving effect of cooling garment decreased as metabolic rate increased. • Cooling garment increased working efficiency, less time was used in cognitive test. [ABSTRACT FROM AUTHOR]

AbstractThe prefabricated vertical drain (PVD) alleviating clogging mechanism under different air injection pressure and time is not clear for air-boosted vacuum preloading. The computational fluid dynamic-discrete element method (CFD-DEM) is developed to dynamically observe PVD clogging and investigate the PVD clogging mechanism. i.e., PVD discharge rate, soil particle migration, and porosity change under the different air injection patterns of vacuum preloading with no air injection, constant air injection pressure of 75 kPa, and variable air injection pressure of 25∼150 kPa. Compared with conventional vacuum preloading with no air injection, the water discharge rate of PVD can be increased, clogging layer area can be reduced significantly for air-boosted vacuum preloading. The porosity near the air injection port is greater than that close to the PVD. The consolidation mechanism of air-boosted vacuum preloading the disturbance effect in the early stage of consolidation, the pressurization effect in the middle stage of consolidation, and the clogging effect in the later stage of consolidation are revealed. Three kinds of laboratory model tests are run to demonstrate air injection alleviating PVD clogging. The results demonstrate that increasing the air injection pressure can significantly alleviate PVD clogging. [ABSTRACT FROM AUTHOR]

Here we numerically and experimentally demonstrate the conversion of normally incident light into the guiding modes of distributed Bragg reflector (DBRs) mirror. By fabricating a gold grating onto a 7.5 pairs TiO2/SiO2 DBR mirror, a series of asymmetrical resonances have been formed at the bandgap range of the DBR mirror. The detailed numerical calculations show that these Fano resonances are attributed to the coupling of incident waves into guiding modes of the DBR mirror. Compared with the other resonances, this coupling mechanism can be simply realized and it has also been revealed to be quite robust to the environmental changes, making the conversion between propagating waves and guiding waves to be practically interesting for many applications. [ABSTRACT FROM AUTHOR]

Recently, on-chip single-mode laser emissions in coupled microdisks have attracted considerable research attention due to their wide applications. While most of single-mode lasers in coupled microdisks or microrings have been qualitatively explained by either Vernier effect or inversed Vernier effect, none of them have been experimentally confirmed. Here, we studied the mechanism of single-mode laser operation in coupled microdisks. We found that the mode numbers had been significantly reduced to nearly single-mode within a large pumping power range from threshold to gain saturation. The detail laser spectra showed that the largest gain and the first lasing peak were mainly generated by one disk and the laser intensity was proportional to the wavelength detuning of two set of modes. The corresponding theoretical analysis showed that the experimental observations were dominated by internal coupling within one cavity, which was similar to the recently explored inversed Vernier effect in two coupled microrings. We believe our finding will be important for understanding the previous experimental findings and the development of on-chip single-mode laser. [ABSTRACT FROM AUTHOR]