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This study comprises two meta-analyses conducted to investigate relations between socioeconomic status (SES) and academic achievement, with a focus on macro-level, micro-level, and methodological moderating variables in primary and secondary education. The first meta-analysis is based on 326 empirical studies with 949,699 students from 47 countries and areas, and the second is based on three international large-scale assessments (i.e., PISA, TIMSS, and PIRLS) with 1230 independent samples of 5,095,283 students from 105 countries and areas. We found moderate correlations between SES and academic achievement across the world, rs = 0.22 [approximately] 0.28. Moderation analyses revealed that (a) these relations have strengthened since the 1990s; (b) GDP per capita and economic equality did not affect the relations; (c) higher net enrollment ratio and longer duration of compulsory education did not weaken these relations; (d) the relations stayed stable or even strengthened across grades in concurrent and longitudinal designs. Taken together, our findings suggest that educational expansion that focuses on increasing educational opportunities does not seem to reduce inequalities in academic outcomes between high- and low-SES school children in educational systems on the national level. Quality indicators for educational expansion, however, should be considered in setting educational policy to achieve inclusive, equitable education.

Previous studies have focused more on the facilitating effect of nature exposure on positive behavioural consequences. However, less attention has been paid to whether nature exposure can inhibit internalized problem behaviours, such as Internet addiction. Within the framework of the stimuli‐organism‐response theory, the present study examined the relationship between nature exposure and Internet addiction and investigated the mediating roles of anthropomorphism of nature and awe. In China, we recruited 1469 adolescents (mean age = 13.90 years old, SD = 0.59, 53.2% girls). Mediation analyses indicated that awe partially mediated the relationship between nature exposure and adolescents' Internet addiction. The anthropomorphism of nature and awe served as sequential mediating roles in the relationship between nature exposure and adolescents' Internet addiction. This study provides a nature‐based perspective on the prevention and intervention of adolescents' Internet addiction. [ABSTRACT FROM AUTHOR]

PET/PA6, hollow, segmented-pie, microfiber nonwovens (PET/PA6 HSMNs) play an important role in a microfiber, synthetic leather base. Most of the current PET/PA6 HSMNs generally lack in hygiene performance. Moreover, there is an urgent need for the asymmetric wettability of PET/PA6 HSMNs to ensure the comfort of clothing. In this work, a novel, asymmetrically wettable, PET/PA6 HSMN with a gradient structure is proposed, which can regulate liquid adsorption and directional transport. An MOF-303 was successfully synthesized and loaded onto the PET/PA6 HSMN, which had been pre-treated with gradient hydrolysis under sulfuric acid. The droplet quickly permeated the modified PET/PA6 HSMN, and the droplet disappearance time decreased to 62.40 ms. The liquid strikethrough time of the modified PET/PA6 HSMN reached 5.16 s. The maximum adsorption capacity of the modified PET/PA6 HSMN was 68.161 mg/g, which was improved by 122.83%. In addition, the air permeability of the pre-treated PET/PA6 HSMN increased from 308.70 mm/s to 469.97 mm/s, with the sulfuric acid concentrations increasing from 0% to 20%, and the air permeability of the modified PET/PA6 HSMN decreased gradually from 247.37 mm/s to 161.50 mm/s. Furthermore, the tensile strength of the modified PET/PA6 HSMN treated with sulfuric acid and MOF-303 was also obviously enhanced compared with the PET/PA6 HSMN treated with pure sulfuric acid. This PET/PA6 HSMN, with asymmetric wettability, owing to its high hygiene performance and water transport capabilities, is promising and able to extend the application of a microfiber synthetic leather base for clothing. [ABSTRACT FROM AUTHOR]

This study, grounded in developmental systems theory, investigated the roles of family functioning, peer relationships, and adolescents' dark personality traits related to behavioral adjustment so that we would delve deeper into these relations. Cross-sectional data from 1,878 Chinese adolescents (759 females; M age = 14.97 years) was used. Results revealed that psychopathy was the strongest predictor of adolescents' behavioral adjustment. In addition, mediation analysis highlighted the indirect roles of psychopathy and peer relationship between family functioning and behavioral adjustment. These findings clarify the mechanisms of driving adolescents' behavioral adjustment and highlight the importance of future youth programs focusing on the family as a unit and preventing the development of psychopathy simultaneously. [ABSTRACT FROM AUTHOR]

Bicomponent spunbond hydroentanglement technology can break the interface between the two components by physical extrusion and shearing, thereby realizing the green and efficient production of high-strength microfiber nonwoven materials. Herein, we report a soft and fluffy bicomponent spunbond hydroentanglement nonwoven material using high-shrinkage polyester/polyamide 6 (HSPET/PA6) as the bicomponent. HSPET/PA6 hollow segmented pie composite fibers with different volume ratios were prepared by spunbond technology, the HSPET and PA6 segments were alternately arranged, and the interface was flat. The composite fibers were split by heat treatment. The dry heat shrinkage rates of the composite fibers were 8.45% (50/50) and 10.57% (70/30), and the boiling water shrinkage rates were 10.02% (50/50) and 12.27% (70/30). HSPET/PA6 hollow segmented pie microfiber nonwovens were prepared by hydroentanglement technology. After heat treatment, the fibers of nonwovens were further split and the HSPET fibers curled, giving the nonwovens a fluffy characteristic. By comparing the properties of HSPET/PA6 after heat treatment, the shrinkage effect of the water bath was obviously better than that of dry heat, and the split degree of fibers reached 81.97% (50/50) and 84.65% (70/30). Compared with polyester/PA6 nonwovens, the softness of HSPET/PA6 nonwovens increased by 45.1% (50/50) and 49.3% (70/30) after boiling water shrinkage. At the same time, the mechanical properties of HSPET/PA6 nonwovens were also improved. The successful fabrication of HSPET/PA6 microfiber nonwovens provides a new method for enhancing the softness of bicomponent spunbond hydroentanglement nonwovens. [ABSTRACT FROM AUTHOR]

The microfiber synthetic leather base (MSLB) was prepared by mixing hollow segmented pie microfibers and polyacrylonitrile electrospun nanofibers. Micro/nano hybrid leather base was prepared to simulate the three-dimensional (3D) structure of natural leather. The diameter of the polyacrylonitrile nanofibers was 950 nm, 450 nm and 200 nm, respectively. The effects of nanofibers of different diameters on the performances of MSLB were investigated. The results indicated that polyacrylonitrile nanofibers were randomly dispersed in MSLB. Differential scanning calorimetry further demonstrated the presence of polyacrylonitrile nanofibers in MSLB, and thermogravimetric analysis showed that the addition of polyacrylonitrile nanofibers had a little influence on the thermal stability of MSLB. There was no significant change in the water contact angle of the MSLB surface before and after the addition of nanofibers. As the diameter of the nanofibers decreased from 950 nm to 200 nm, the static water vapor transmission rate was increased by 28.2%, the softness was increased by 39.74%, and air permeability was decreased by 17.16%. When the nanofiber diameter is 950 nm, the moisture absorption performance of MSLB was better, which was 768.99%. Moreover, the tear strength was also significantly enhanced by 105.76%. [ABSTRACT FROM AUTHOR]

Compared to natural leather, microfiber synthetic leather has many excellent qualities, such as chemical resistance and physical and mechanical properties. However, preparation of microfiber synthetic leather with a high water vapor transmission rate (WVT), moisture absorption and wearing comfort property is still a challenge. In this study, we prepared thermoplastic polyurethane (TPU)/sulfonated polysulfone (SPSf) electrospun nanofibers and applied them to a microfiber synthetic leather base (MSLB). The effects of TPU/SPSf nanofiber content on the structure and properties of the MSLB were investigated. The results indicated that the TPU/SPSf nanofibers with an average diameter of 0.12 µm were well distributed at all directions in the MSLB. Differential scanning calorimetry analysis showed four T g peaks, further demonstrating the existence of TPU/SPSf nanofibers. With the increase of TPU/SPSf nanofiber content from 0 to 30 wt%, the contact angles decreased gradually from 111.64° to 67.07°, leading to 55.19% improvement in the WVT value (from 2868.96 to 4452.24 g/(m2•24 h)) and 26.25% improvement in the moisture absorption (from 628.70% to 793.75% mm/s). Simultaneously, when the nanofiber content was 30 wt%, the nanofibers tended to bundle and 6.79% decrement of air permeability was observed. Specifically, the softness of the MSLB was improved by 88.55%. Moreover, the thermal stability and the tear strength were also obviously enhanced. Consequently, this research provided a feasible and promising way to prepare a high-performance MSLB using TPU/SPSf nanofibers. [ABSTRACT FROM AUTHOR]

Nowadays the waterborne polyurethane (WPU) is a newly developed polymer foam material as a replacement for conventional organic solvent‐based polyurethane (PU). Nevertheless, the WPU foams exhibit some drawbacks such as inferior mechanical strength, low thermal and dimensional stability, which inhibits its large‐scale application at present. So a series of novel WPU/silver nanocomposite foams was successfully prepared by mechanical foaming method. The effect of silver nanoparticles (nano Ag) content on the morphology, thermal behavior, air permeability, water vapor transmission rate (WVT), mechanical, and antibacterial properties of WPU/Ag nanocomposite foams were systematically investigated. The results revealed that the nano Ag were uniformly dispersed in WPU matrix and facilitated cell growth, leading to enhanced mean pore size, thermal stability, air permeability, and WVT value of nanocomposite foams. About 122% improvement in the air permeability and 28% improvement in the WVT value were obtained when the nano Ag content extended from 0 to 4 wt%. It was found that the nano Ag content had great influence on tensile strength and elongation at break. When nano Ag content was 2 wt%, the nanocomposite foam exhibited the maximum tensile strength value of 1.26 MPa. Moreover, because of the addition of nano Ag, the nanocomposite foam showed bacteriostatic rate of 98.23% and 97.38% against Escherichia coli and Staphylococcus aureus, respectively. POLYM. COMPOS., 40:1492–1498, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Highlights: [•] A facile and one-pot approach was employed to prepare nanosized La3+ doped Zn ferrites. [•] Magnetic properties of the samples were modified by CTAB. [•] CTAB can be used to affect the dispersion of La3+ in Zn ferrite with the same content of La3+. [ABSTRACT FROM AUTHOR]

Highlights: [•] A core–shell structure of ZnLa0.02Fe1.98O4/PPy nanoparticles was facilely fabricated at room temperature. [•] The saturation magnetization and electric conductivity of the sample are 26.0±0.2emu/g, 169±2S/cm, respectively. [•] The ZnLa0.02Fe1.98O4/PPy shows higher adsorption rate and capacity in removal of anionic organic dye, methyl orange (MO), from water than that of ZnLa0.02Fe1.98O4. [ABSTRACT FROM AUTHOR]

Abstract: Core–shell structure of Fe3O4/Ag/polypyrrole (PPy) nano-particles (NPs) was prepared by a facile method through the redox reaction of silver nitrate and pyrrole in the presence of polyvinyl pyrrolidone (PVP) as protection agent. The presence of PVP has an effect on the morphology and structure of the Fe3O4/Ag/PPy NPs. Rod-shaped Fe3O4/Ag/PPy NPs were obtained with the increase of the concentration of PVP to 0.125mM, in which the wire-like core was formed by the aggregation of Fe3O4 and Ag nanoparticles. At the same time, the PPy shell of the NPs became more uniform and thicker with the increase of the concentrations of PVP and AgNO3 in the solution. The electric conductivity of the NPs can be enhanced to 335±8S/cm by incorporation of the Ag into the NPs. At the same time, the thickness of the PPy shell affects the electric conductivity of the samples. All the NPs in the present work exhibit superparamagnetic behavior. [Copyright &y& Elsevier]

Abstract: An anionic surfactant, sodium dodecyl sulfate (SDS), was used to modify fabrication of La3+ doped zinc ferrite (ZnLa0.02Fe1.98O4) clusters with a facile and efficient one-pot solvothermal method, where these clusters were aggregated by magnetic nanoparticles. The effects of SDS on magnetic properties of the samples were investigated. The saturation magnetization (M s ) of the samples increases when the concentration of SDS is increased to 15mM, and it decreases when the concentration of SDS further increased to 20mM. The maximum M s of the sample is 101.0±0.2emu/g. The coercivity of the samples decreased significantly when SDS was added in the reaction systems. And it remains at about 5–8Oe when the concentration of SDS is between 5 and 20mM. [Copyright &y& Elsevier]