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Steroid-induced osteonecrosis of the femoral head (SONFH) is a prevalent form of osteonecrosis in young individuals. More efficacious clinical strategies must be used to prevent and treat this condition. One of the mechanisms through which SONFH operates is the disruption of normal differentiation in bone marrow adipocytes and osteoblasts due to prolonged and extensive use of glucocorticoids (GCs). In vitro, it was observed that atorvastatin (ATO) effectively suppressed the impact of dexamethasone (DEX) on bone marrow mesenchymal stem cells (BMSCs), specifically by augmenting their lipogenic differentiation while impeding their osteogenic differentiation. To investigate the underlying mechanisms further, we conducted transcriptome sequencing of BMSCs subjected to different treatments, leading to the identification of Wnt5a as a crucial gene regulated by ATO. The analyses showed that ATO exhibited the ability to enhance the expression of Wnt5a and modulate the MAPK pathway while regulating the Wnt canonical signaling pathway via the WNT5A/LRP5 pathway. Our experimental findings provide further evidence that the combined treatment of ATO and DEX effectively mitigates the effects of DEX, resulting in the upregulation of osteogenic genes (Runx2, Alpl, Tnfrsf11b, Ctnnb1, Col1a) and the downregulation of adipogenic genes (Pparg, Cebpb, Lpl), meanwhile leading to the upregulation of Wnt5a expression. So, this study offers valuable insights into the potential mechanism by which ATO can be utilized in the prevention of SONFH, thereby holding significant implications for the prevention and treatment of SONFH in clinical settings. [ABSTRACT FROM AUTHOR]

Application of tissue-engineered bones (TEBs) is hindered by challenges associated with incorporated viable cells. Previously, we employed freeze-drying techniques on TEBs to devitalize mesenchymal stem cells (MSCs) while preserving functional proteins, yielding functional proteins-based TEBs (FP-TEBs). Here, we aimed to elucidate their in vivo angiogenic and osteogenic capabilities and the mechanisms. qPCR arrays were employed to evaluate chemokines and receptors governing EC migration. Identified C-X-C chemokine receptors (CXCRs) were substantiated using shRNAs, and the pivotal role of CXCR2 was validated via conditional knockout mice. Finally, signaling molecules downstream of CXCR2 were identified. Additionally, Src, MAP4K4, and p38 MAPK were identified indispensable for CXCR2 function. Further investigations revealed that regulation of p38 MAPK by Src was mediated by MAP4K4. In conclusion, FP-TEBs promoted EC migration, angiogenesis, and osteogenesis via the CXCR2-Src-Map4k4-p38 MAPK axis. [ABSTRACT FROM AUTHOR]

The present study investigated multilevel models posited to predict student approaches to homework. Participants were 1,072 middle school students in China. Results revealed that deep and surface approaches were positively associated with performance-approach. Furthermore, deep approach to homework was associated negatively with homework cost, yet positively with mastery-approach, homework expectancy, and prior knowledge. Surface approach to homework was associated positively with homework cost and parent education, yet negatively with homework expectancy and mastery-approach. Females were less likely to use surface approach to homework than males. At the class level, surface approach to homework was negatively associated with parent education. Implications for homework practice and future investigation are discussed in terms of these results. [ABSTRACT FROM AUTHOR]

This study investigated multilevel models of homework time management involving Chinese middle school students. At the individual level, homework time management was positively associated with arranging the environment, monitoring motivation, time on homework, and teacher and parent autonomy support. Additionally, homework time management was positively related to teacher autonomy support at the class level. Taken together, this study extended previous research, by indicating that homework time management was positively related to teacher and parent autonomy support when accounting for other theoretically pertinent variables. Implications of these results are explored with respect to homework practices and potential avenues for future investigation. [ABSTRACT FROM AUTHOR]

Bio-based materials as flame retardants meet the requirements of green strategy and sustainable development. Here nitrogen and phosphorus-modified bio-based cellulose nanocrystal composite (NPCNCs) were designed and added to epoxy resin (EP) to determine fire safety and mechanical properties. NPCNCs were successfully synthesized using ice bath polymerization and exhibited a fibrous appearance with rough surface. When corresponding into EP, NPCNCs endowed EP composite with excellent flame retardancy. For EP/6NPCNCs, the LOI value was 27.6% which was higher than that of pure EP (23.5%). Compared with pure EP, the total heat release, peak heat release rate, total smoke production and peak smoke production rate values of EP/6NPCNCs decreased by 27.27%, 43.34%, 70.21% and 66.67%. This was attributed to catalysis-dehydration and carbonization, carbon support of cellulose nanocrystals and gas phase dilution. In addition, the flame retardant EP composite mechanical properties were basically maintained compared with the pure EP. This article will provide a new way for the design bio-based P and N-modified flame retardants. [ABSTRACT FROM AUTHOR]

Objective: This study was designed to investigate the clinical features, treatment modalities, and risk factors influencing neurological recovery in patients who underwent scoliosis correction with delayed postoperative neurological deficit (DPND). Methods: Three patients with DPND were identified from 2 central databases for descriptive analysis. Furthermore, all DPND cases were retrieved from the PubMed and Embase databases. Neurological function recovery was categorized into complete and incomplete recovery groups based on the American Spinal Injury Association (ASIA) impairment scale. Results: Two patients were classified as type 3, and one was classified as type 2 based on the MRI spinal cord classification. Intraoperative neurophysiological monitoring (IONM) was consistently negative throughout the corrective procedure, and intraoperative wake-up tests were normal. The average time to DPND development was 11.8 h (range, 4–18 h), and all three patients achieved complete recovery of neurological function after undergoing revision surgery. A total of 14 articles involving 31 patients were included in the literature review. The mean time to onset of DPND was found to be 25.2 h, and 85.3% (29/34) of patients experienced DPND within the first 48 h postoperatively, with the most common initial symptoms being decreased muscle strength and sensation (26 patients, 83.9%). Regarding neurological function recovery, 14 patients were able to reach ASIA grade E, while 14 patients were not able to reach ASIA grade E. Univariate analysis revealed that preoperative diagnosis (p = 0.004), operative duration (p = 0.017), intraoperative osteotomy method (p = 0.033), level of neurological deficit (p = 0.037) and deficit source (p = 0.0358) were significantly associated with neurological outcomes. Furthermore, multivariate regression analysis indicated a strong correlation between preoperative diagnosis (p = 0.003, OR, 68.633; 95% CI 4.299–1095.657) and neurological prognosis. Conclusion: Our findings indicate that spinal cord ischemic injury was a significant factor for patients experiencing DPND and distraction after corrective surgery may be a predisposing factor for spinal cord ischemia. Additionally, it is important to consider the possibility of DPND when limb numbness and decreased muscle strength occur within 48 h after corrective scoliosis surgery. Moreover, emergency surgical intervention is highly recommended for DPND caused by mechanical compression factors with a promising prognosis for neurological function, emphasizing the importance of taking into account preoperative orthopedic diagnoses when evaluating the potential for neurological recovery. [ABSTRACT FROM AUTHOR]

To effectively reduce carbon emissions from the manufacturing industry and promote green and sustainable developments evolutionary game theory is widely used. This study has constructed a four-party evolutionary game model, in which the government, civil environmental protection organisations, manufacturing enterprises, and consumers participate. A local robustness analysis and numerical simulation were used to assess the stability conditions under which the strategic behaviour of the four parties reaches an ideal state, and the influence of government parameter changes on the game system were further analysed. The results show that when the government's penalty is greater, the decision-making time of civil environmental protection organisations and manufacturing enterprises is shortened to varying degrees. When the subsidy coefficient provided by the government increases, civil environmental protection organisations, manufacturing enterprises, and consumers can reduce the time required for the system to stabilise to varying degrees. As the subsidy coefficient increases, the government's strategic choice evolves and strict regulations are loosened. The government should thus actively establish a reward and penalty mechanism, according to its own actual situation, set reasonable punishment and subsidy coefficients, and actively guide the subjective initiative of civil environmental protection organisations to reduce carbon emissions in the manufacturing industry. [ABSTRACT FROM AUTHOR]

Kinesin is a kind of motor protein, which interacts with microtubule filaments and regulates cellulose synthesis. Cotton fiber is a natural model for studying the cellular development and cellulose synthesis. Therefore, a systematic research of kinesin gene family in cotton (Gossypium spp.) will be beneficial for both understanding the function of kinesin protein and assisting the fiber improvement. Here, we aimed to identify the key kinesin genes present in cotton by combining genome-wide expression profile data, association mapping, and public quantitative trait loci (QTLs) in upland cotton (G. hirsutum L.). Results showed that 159 kinesin genes, including 15 genes of the kinesin-13 gene subfamily, were identified in upland cotton; of which 157 kinesin genes can be traced back to the diploid ancestors, G. raimondii and G. arboreum. Using a combined analysis of public QTLs and genome-wide expression profile information, there were 29 QTLs co-localized together with 28 kinesin genes in upland cotton, including 10 kinesin-13 subfamily genes. Genome-wide expression profile data indicated that, among the 28 co-localized genes, seven kinesin genes were predominantly expressed in fibers or ovules. By association mapping analysis, 30 kinesin genes were significantly associated with three fiber traits, among which a kinesin-13 gene, Ghir_A11G028430, was found to be associated with both cotton boll length and lint weight, and one kinesin-7 gene, Ghir_D04G017880 (Gh_Kinesin7), was significantly associated with fiber strength. In addition, two missense mutations were identified in the motor domain of the Gh_Kinesin7 protein. Overall, the kinesin gene family seemingly plays an important role in cotton fiber and boll development. The exploited kinesin genes will be beneficial for the genetic improvement of fiber quality and yield. [ABSTRACT FROM AUTHOR]

Combining bio-based functional reagents and biopolymers has become a solution to address the needs of sustainability, health, and safety as society has grown. This study developed a waterproof and intumescent flame retardant system for epoxy resin (EP) by combining hexachlorocyclotriphosphazene and melamine with vanillin, synthesizing a ternary polymer flame retardant (HCPVM), combining carbon and gas sources, and using piperazine pyrophosphate (PAPP) as an acid source. The test results showed that HCPVM could participate in the curing reaction of EP and improve the mechanical properties of EP material. At the same time, the flame retardancy and water resistance of the material have been significantly improved. The peak heat release rate (PHRR) of EP/3.5 PAPP/0.5 HCPVM was 65.43% lower than that of pure EP. Additionally, the system's LOI and UL-94 did not significantly change after five days of boiling. In summary, this study's waterproof bio-based intumescent flame retardant solution broadens the application possibilities for EP. [ABSTRACT FROM AUTHOR]

This study classified profiles of homework motivation applying achievement goal theory (AGT) and expectancy-value theory (EVT). Participants were 918 middle school students. Latent profile analysis (LPA) produced a 4-profile solution: Very Low Mastery-Approach, Low Motivation, Moderate Motivation, and High Motivation. Furthermore, profile membership predicted homework behavior and mathematics achievement. Additionally, there was the added benefit of combining both theories while creating homework motivational profiles. Our study suggests that promoting all four types of homework motivation beliefs, particularly with mastery-approach, may result in most desirable patterns of homework behavior and academic achievement. [ABSTRACT FROM AUTHOR]

Paravertebral muscles (PVM) act as one of the major dynamic factors to maintain human upright activities and play a remarkable role in maintaining the balance of the trunk. Adult degenerative scoliosis (ADS) has become one of the important causes of disability in the elderly population owing to the changes in spinal biomechanics, atrophy and degeneration of PVM, and imbalance of the spine. Previously, many studies focused on the physical evaluation of PVM degeneration. However, the molecular biological changes are still not completely known. In this study, we established a rat model of scoliosis and performed the proteomic analysis of the PVM of ADS. The results showed that the degree of atrophy, muscle fat deposition, and fibrosis of the PVM of rats positively correlated with the angle of scoliosis. The proteomic results showed that 177 differentially expressed proteins were present in the ADS group, which included 105 upregulated proteins and 72 downregulated proteins compared with the PVM in individuals without spinal deformities. Through the construction of a protein–protein interaction network, 18 core differentially expressed proteins were obtained, which included fibrinogen beta chain, apolipoprotein E, fibrinogen gamma chain, thrombospondin-1, integrin alpha-6, fibronectin-1, platelet factor 4, coagulation factor XIII A chain, ras-related protein Rap-1b, platelet endothelial cell adhesion molecule 1, complement C1q subcomponent subunit A, cathepsin G, myeloperoxidase, von Willebrand factor, integrin beta-1, integrin alpha-1, leukocyte surface antigen CD47, and complement C1q subcomponent subunit B. Further analysis of the Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) and immunofluorescence showed that the neutrophil extracellular traps (NETs) formation signaling pathway plays a major role in the pathogenesis of PVM degeneration in ADS. The results of the present study preliminarily laid the molecular biological foundation of PVM atrophy in ADS, which will provide a new therapeutic target for alleviating PVM atrophy and decreasing the occurrence of scoliosis. [ABSTRACT FROM AUTHOR]

The major objectives of our study were (a) to identify student profiles according to five homework characteristics (homework time, frequency, quality, interest, and favorability) and (b) to examine their relationship with three critical variables in the homework process—homework effort, completion, and math achievement. Latent profile analysis (LPA) was used to examine a data set with 3018 8th graders in China. Based on these characteristics, five distinct profiles were identified: Profile 1 (Low), Profile 2 (Moderate Time/High With Others), Profile 3 (Low Frequency/Moderate With Others), Profile 4 (Moderate Time/High Frequency/Low With Others), and Profile 5 (High Time and Frequency/Moderate With Others). Parent education was positively associated with the two healthiest profiles (Profile 2 and Profile 5). Finally, profile membership was a significant predictor of homework effort, completion, and math achievement. Specifically, our study suggests that students can work about 30 min on math homework and achieve the same results, if they work often, with high quality, fueled by interest and favorability (compared with students who spend about 110 min on math homework). Taken together, our study provided novel insights into the combination of homework characteristics that could have significant implications for homework practice and research. [ABSTRACT FROM AUTHOR]

The present study investigated the predictive effects of clusters of variables on homework environment management based on the data from 3018 students in Grade 8. These clusters included: background variables, homework characteristics, adult support and monitoring, homework purposes, goal orientations, and contextual control. At the individual level, management of homework environment was significantly related to at least one variable from each of the six clusters. Specifically, it was associated negatively with time spent watching TV, and positively with prior achievement, homework interest, homework quality, family help, teacher feedback, academic purpose, self-regulatory purpose, mastery-approach, and help seeking. Additionally, males managed homework environment less frequently than females. Finally, management of homework environment was positively related to homework quality at the class level. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA), one of the major diseases afflicting the elderly, is a type of degenerative joint disease related to cartilage and synovium. This study aimed to clarify the role and mechanism of adipose mesenchymal stem cell (ADSC)-derived exosomes (Exos) in OA-induced chondrocyte degradation and synovial hyperplasia, thus improving the quality of life of patients. The rat OA model, chondrocytes, synovial fibroblast models and immunofluorescence were applied to observe the in vivo and in vitro functions of human ADSC (hADSC)-derived Exos in OA and its possible regulatory signaling pathways. Bioinformatics software and luciferase reporter assay were carried out to verify the mechanism of microRNA-376c-3p (miR-376c-3p) in hADSC-derived Exos in OA in vitro. Moreover, Safranine O-Fast Green Cartilage staining, Masson staining, immunohistochemistry and immunofluorescence were conducted to verify the role of miR-376c-3p in hADSC-derived Exos in OA in vivo. hADSC-derived Exos mitigated OA-induced chondrocyte degradation and synovial fibrosis both in vivo and in vitro models by repressing the WNT-beta-catenin signaling pathway. For the mechanism exploration in vitro, miR-376c-3p was raised in hADSC-derived Exos and mediated the fibrosis of synovial fibroblasts in OA, and miR-376c-3p targeted the 3'-untranslated region of WNT3 or WNT9a. Meanwhile, the in vivo experiments also corroborated that the miR-376c-3p in hADSC-derived Exos mitigated OA-induced chondrocyte degradation and synovial fibrosis. MiR-376c-3p in hADSC-derived Exos repressed the WNT-beta-catenin pathway by targeting WNT3 or WNT9a, and then mitigating OA-induced chondrocyte degradation and synovial fibrosis, thereby providing theoretical basis for clinical implementation of treatment. [ABSTRACT FROM AUTHOR]

Informed by expectation-value theory and related literature, the goal of the current investigation was to identify profiles of students drawn from three purposes of homework (academic, self-regulatory, and approval-seeking). Participants were 750 eleventh-grade students in China. Results from latent profile analysis (LPA) revealed identified four different profiles of students: Very Low Profile (very low in all purposes; 5.73%), Low Profile (low in all purposes; 30.40%), Moderate Profile (moderate in all purposes; 54.40%), and High Profile (high in all purposes; 9.47%). Results further revealed that student gender was associated with profile membership. Finally, profile membership was significantly related to homework effort and completion (with a medium effect size) in that, in general, the higher the homework purposes, the higher the homework effort and homework completion. [ABSTRACT FROM AUTHOR]

This paper presents the effect of wind tunnel sidewalls on the wind turbine airfoils with experimental and numerical methods. The test is carried out in a low-speed wind tunnel at Re=2.62×105. Pressures acting on the airfoil surface are measured by a multiport pressure device. And, the oil flow visualization technique is used to investigate the flow field characteristics of the airfoil surface. Then, a numerical simulation was conducted with the measurement results. As a result, it is clarified the flow structures on the airfoil surface depend strongly on the angles of attack and the sidewalls. At small angles of attack, the three-dimensional separation caused by the interaction between the sidewall boundary layer and the airfoil boundary layer is very small, and only appears near the junction of the airfoil model and the sidewall. This corner separation becomes large with the increase of the angle of attack. At the middle part of the testing model, the boundary layer flow evolves into three-dimensional separation, i.e., stall cell, when the separation develops to an appreciate extent. The stall phenomenon will further spread from the center line to sidewalls with the increase of the angle of attack; and then, its development will be limited by the sidewall boundary layer separation. Comparably, the simulation shows that the sidewall make the pressure coefficient Cp decrease, and proper boundary condition can maintain two-dimensional flow at large angles of attack by eliminating the influence of corner vortices. [ABSTRACT FROM AUTHOR]

Research in the field of homework has confirmed the significant association between students' perceptions of their parents' involvement and their motivation and engagement with these tasks. In this study we analyzed the possible mediating role of self-handicapping strategies in the relationship between perceptions of parental support (content-oriented and autonomy-oriented support) when doing homework and the students' behavioral engagement (time spent, effort made, amount of homework done, level of procrastination). The participants were 643 students in compulsory secondary education (between 7th and 10th grade). The results showed that the lower the perceptions of support from parents when doing homework, the greater the students' use of self-handicapping strategies and the worse their behavioral engagement (less effort, less amount of homework done, more procrastination) and vice versa. These findings seem to indicate that self-handicapping is a motivational strategy that would partially explain students' poor behavioral engagement with homework in the absence of parental support. [ABSTRACT FROM AUTHOR]

This work utilizes wet–dry cycle corrosion tests to investigate the corrosion behavior of medium manganese steel by analyzing its corrosion kinetics, corrosion phases, surface morphology, cross-section morphology, elemental distribution and electrochemical characteristics. The corrosion process was divided into two stages, and the change is due to the unique transformation of corrosion products. The mixture of β-FeOOH and MnO2 in the corrosion product up to 72 h causes an increase in redox ability and electronic transmission rate and enlarges the specific surface in the initial corrosion products. The transformation of the unique mixture determines the transformation of the corrosion process. [ABSTRACT FROM AUTHOR]

Informed by two theoretical models of homework effects, we extended a model of homework on mathematics achievement in a large sample of Chinese eighth graders. Our model incorporated six clusters of homework variables – student background factors, homework characteristics, teacher variables, parent variables, student motivation, and homework behavior. Results indicated that mathematics achievement was related to at least one variable for each of the six clusters at the individual level. At the class level, mathematics achievement was associated positively with homework time, frequency, and interest, but negatively with teacher control. Finally, the combination of prior grades in mathematics and homework completion together influenced mathematics achievement. The study highlights the utility of our extended theoretical model for understanding predictive effects on achievement in a non-Western sample. The different norms and practices around homework in China are discussed, as are implications for future research. [ABSTRACT FROM AUTHOR]

The current investigation evaluates the psychometric properties of the Online Homework Goal Orientation Scale (OHGOS) for college students. Participants were 612 college students in China. Results revealed that the OHGOS included two subscales: mastery- and performance-approaches. Results further revealed that intercept was invariant across gender for both mastery- and performance-approaches, suggesting that the OHGOS is applicable for both females and males. Additionally, consistent with theoretical predictions, mastery-approach (in comparison with performance-approach) was more strongly related to online homework effort, completion, emotion regulation, arranging study environment, time management, and help seeking. Taken together, our present study finds strong evidence that the OHGOS is a valid instrument of online homework goal orientations. [ABSTRACT FROM AUTHOR]

This paper compares the microstructure and mechanical evolution in a high-strength quenched and micro-alloyed steel during the austenitising bending process. Simulation results indicated a new finding that the stress neutral layer (SNL) tends to move to the tension zone during straining. The hardness gradient detected from the centre to compression/tension zones was resulted from comprehensive factors: First of all, the location of SNL revealed a prominent impact on strength. Second, the dislocation accumulation would be responsible for the hardness gradient on the surfaces. In addition, the overall strength decrease during straining was mainly ascribed to integrated effects of dynamic recovery (DRV) and dynamic recrystallisation (DRX). Apart from that, overall smaller martensite packet size and coarser prior austenite grains resulted in the increased hardness value at a lower bending degree. Also, the high consistency between experimental and simulation results is instructive for the practical forming process of railway spring fasteners. [ABSTRACT FROM AUTHOR]

The aim of the current investigation was to validate High Level Cognitive Strategies Scale (HLCSS) using the data from 3018 8th graders in China. The factorial results revealed that the HLCSS included three distinct yet related subscales: organization, elaboration, and critical thinking. Additionally, the HLCSS achieved a high level of measurement invariance over gender, and there was further support for latent factor mean invariance across gender. Concerning the predictive validity of the HLCSS, the present study found that organization, elaboration, and critical thinking were positively associated with math achievement. The correlation between critical thinking and math achievement was stronger than the correlation between elaboration and math achievement, which in turn was stronger than the correlation between organization and math achievement. [ABSTRACT FROM AUTHOR]

The aim of our investigation is to identify teacher motivation profiles towards information technology, according to achievement goal and expectancy-value theories. Latent profile analysis (LPA) was applied to examine if homogenous latent profiles exist within a sample of 866 teachers in China. Four distinct profiles of teachers were identified: Very Low Goal Orientation, High Goal Orientation, High Mastery-Approach and Expectancy/Very Low Work-Avoidance, and Low Mastery- and Performance-Approach. Furthermore, profile membership was related to monitoring motivation, effort, help seeking, and future intention. Finally, we found the added benefits of integrating achievement goal and expectancy-value theories when forming teacher motivation profiles. These results, taken together, suggest that support for teacher motivation to use information technology ought to be differentiated. [ABSTRACT FROM AUTHOR]

Traumatic brain injury (TBI) is an important cause of death in young adults and children. Till now, the treatment of TBI in the short- and long-term complications is still a challenge. Our previous evidence implied aquaporin 4 (AQP4) and hypoxia inducible factor-1α (HIF-1α) might be potential targets for TBI. In this study, we explored the roles of AQP4 and HIF-1α on brain edema formation, neuronal damage and neurological functional deficits after TBI using the controlled cortical injury (CCI) model. The adult male Sprague Dawley rats were randomly divided into sham and TBI group, the latter group was further divided into neutralized-AQP4 antibody group, 2-methoxyestradiol (2-ME2) group, and their corresponding control, IgG and isotonic saline groups, respectively. Brain edema was examined by water content. Hippocampal neuronal injury was assessed by neuron loss and neuronal skeleton related protein expressions. Spatial learning and memory deficits were evaluated by Morris water maze test and memory-related proteins were detected by western blot. Our data showed that increased AQP4 protein level was closely correlated with severity of brain edema after TBI. Compared with that in the control group, both blockage of AQP4 with neutralized-AQP4 antibody and inhibition of HIF-1α with 2-ME2 for one-time treatment within 30–60 min post TBI significantly ameliorated brain edema on the 1st day post-TBI, and markedly alleviated hippocampal neuron loss and spatial learning and memory deficits on the 21st day post-TBI. In summary, our preliminary study revealed the short-term and long-term benefits of targeting HIF-1α-AQP4 axis after TBI, which may provide new clues for the selection of potential therapeutic targets for TBI in clinical practice. [ABSTRACT FROM AUTHOR]

In this study, we designed a new flame retardant to improve the fire safety performance of epoxy resin (EP). Graphitic carbon nitride (g-C3N4) was derived from melamine through a solid-phase reaction, after which nickel ammonium phosphate nanowires (NiNH4PO4·H2O) were grown on the g-C3N4 using a hydrothermal method. The resulting material (g-C3N4/NiNH4PO4·H2O) was a halogen-free flame retardant containing effective flame-retardant elements such as C, N, P, and Ni. Subsequently, g-C3N4/NiNH4PO4·H2O was added to EP to test its fire resistance and mechanical properties. When the amount of g-C3N4/NiNH4PO4·H2O was 5 phr (per hundred resin), the peak of smoke production rate and peak heat release rate of the EP composite were reduced by 35.42 and 70.4 %, respectively, compared to those of pure EP. Meanwhile, the limiting oxygen index of the EP composite was enhanced to 30.0 % from 24.5 % (pure EP). Finally, the flame-retardant mechanisms of the gas phase and condensed phase were explored. [ABSTRACT FROM AUTHOR]

The current study examines reciprocal influences of homework purposes (approval-seeking, self-regulatory, and academic) and math achievement, using data from 1365 students in grade 8 at two measurement points. Results indicated there were positive reciprocal influences of (a) academic purpose and achievement, and (b) academic purpose and self-regulatory purpose. Results further revealed that prior achievement had a positive effect on later self-regulatory purpose. Meanwhile, prior approval-seeking purpose had a negative effect on later achievement. Taken together, the present study advance extant research, by differentiating three types of homework purposes using models of reciprocal influences, and by showing their respective relationships with math achievement over time. [ABSTRACT FROM AUTHOR]

Resistance to chemotherapy drugs is a major factor affecting the surgical outcome and prognosis of osteosarcoma patients. Circular RNAs (circRNAs) play an important role in tumor resistance to chemotherapy. In the present study, we aimed to investigate the role and mechanism of circRNA circ-chitinase 3-like 1.2 (CHI3L1.2) in resistance to cisplatin chemotherapy in osteosarcoma. We found that circ-CHI3L1.2 levels were higher in cisplatin-resistant cells than in their parent cells. circ-CHI3L1.2 knockdown decreased the half-maximal inhibitory concentration (IC50) of cisplatin and the expression levels of P-glycoprotein (P-gp), multidrug-resistance protein 1 (MRP1), and glutathione-S-transferase Pi1 (GSTP1), and promoted apoptosis of cisplatin-resistant osteosarcoma cells. In addition, circ-CHI3L1.2 knockdown induced mesenchymal to epithelial transition (MET) and suppressed cell migration and invasion. The competitive endogenous RNA (ceRNA) mechanism indicated that circ-CHI3L1.2 targets the micro-RNA (miR)-340-5p-lysophosphatidic acid acyltransferase β (LPAATβ) axis, and inhibition of miR-340-5p alleviates the effect of circ-CHI3L1.2 knockdown. In conclusion, circ-CHI3L1.2 levels were increased in cisplatin-resistant osteosarcoma cells and circ-CHI3L1.2 knockdown sensitized cisplatin-resistant osteosarcoma cells to cisplatin through the miR-340-5p-LPAATβ axis. [ABSTRACT FROM AUTHOR]

An internal fixation composite structure of antibiotic cement plates was created. The aim of this study was to analyse the infection control effect of this structure when applied to treat a bone infection. We retrospectively analysed patients with bone infection admitted to our hospital between January 2013 and June 2019. After debridement, an antibiotic cement plate composite structure was used to fill and stabilize the defects. The treatment effect was evaluated at six months after surgery, and the infection control rate, factors associated with the recurrence of infection, and complications were analysed. If the patients had bone defects, the defect was repaired after infection control, and the infection control rate of all of the patients was re-evaluated at 12 months after surgery. A total of 548 patients were treated with this technique, including 418 men and 130 women. The infection sites included 309 tibias, 207 femurs, 16 radii and ulnae, 13 humeri, and 3 clavicles. After at least 6 months of follow-up, 92 patients (16.79%) had an infection recurrence and needed further treatment. The recurrence rate of the tibia was higher than that of the femur (P = 0.025). Eighty-nine out of 92 patients who relapsed underwent a second debridement with the same method, and the infection control rate after the second debridement was 94.71%. Complications included 8 cases of epidermal necrosis around the incision, 6 cases of internal fixation failure, and 30 cases of lower limb swelling. By the follow-up time of 12 months, another 6 patients had experienced recurrence of infection, and 4 cases were controlled after debridement. Finally, among all 548 cases, 7 patients remained persistently infected, and 6 underwent amputation. The infection control rate was 97.6% at the 1-year follow-up. The clinical efficacy of this new antibiotic cement plate composite structure for internal fixation after debridement of bone infection is stable and reliable. [ABSTRACT FROM AUTHOR]

Whereas it is often a challenge to keep students motivated and interested in academic tasks, it is more of a challenge to have students stay motivated and interested in academic tasks outside school during nonschool hours—homework. Prior research, however, has largely overlooked the reasons or purposes students have for doing homework and their interest in homework. Informed by achievement goal theory and interest theory, along with cultural differences pertaining to these theories, the present study uses reciprocal models to study longitudinal relationships among homework goal orientation, interest, and math achievement. Participants were 1450 Chinese students in grade 8. Results found reciprocal influences of mastery-approach and math achievement. Additionally, prior mastery-approach had a positive effect on subsequent performance-approach. Furthermore, prior interest had a positive effect on subsequent mastery-approach. Meanwhile, prior performance-approach negatively influenced subsequent achievement. Taken together, the present study points to the complex interplay among mastery-approach, performance-approach, homework interest, and math achievement over time. These findings hold important practical implications (e.g., to promote mastery-approach and math achievement simultaneously and to help students focus on developing competencies through math homework, not how well they have done compared with their peers). [ABSTRACT FROM AUTHOR]

Purpose: The aim of our study was to evaluate the relationship between the 24-h blood pressure (BP) profile, plasma NT-proBNP levels and left ventricular hypertrophy (LVH) in subjects with primary aldosteronism (PA) compared to patients with essential hypertension (EH). Methods: A total of 385 consecutive patients with PA [187 with aldosterone producing adenoma (APA) and 198 with idiopathic hyperaldosteronism (IHA)] and 385 patients with EH were matched based on age, sex, body mass index (BMI), BP values and duration of hypertension. Twenty-four-hour ambulatory BP monitoring (ABPM), plasma levels of NT-proBNP, left ventricular mass index (LVMI), and other clinical medical data were assessed in all patients. Results: No differences in age, sex, BMI, clinical BP, 24-h mean BP, daytime BP, or duration of hypertension were found between groups. Nighttime systolic BP (130 ± 16 vs. 127 ± 17 mmHg, p < 0.05) and diastolic BP (82 ± 10 vs. 79 ± 11 mmHg, p < 0.01) were higher in PA patients than in EH patients. In addition, nocturnal BP decline was reduced, while median NT-proBNP (53.7 vs. 33.2 pg/ml, P < 0.001) and LVMI (113 ± 25 vs. 102 ± 26 g/m2, P < 0.001) were higher in PA patients than in EH patients. Moreover, the median NT-proBNP level was higher in APA patients than in IHA patients (68.0 vs. 42.4 pg/ml, P < 0.001). In stepwise multivariate regression analysis, LVMI was correlated with NT-proBNP, nighttime systolic BP and sex in PA patients. Conclusions: Patients with PA show higher nighttime BP and NT-proBNP levels and lower nocturnal BP decline than those with EH. In addition, higher nocturnal systolic BP has been shown to be strongly associated with cardiac damage in PA patients. [ABSTRACT FROM AUTHOR]

Ankylosing spondylitis (AS) is chronic inflammatory arthritis with a progressive fusion of axial joints. Anti-inflammatory treatments such as anti-TNF-α antibody therapy suppress inflammation but do not effectively halt the progression of spine fusion in AS patients. Here we report that the autoimmune inflammation of AS generates a microenvironment that promotes chondrogenesis in spine ligaments as the process of spine fusion. Chondrocyte differentiation was observed in the ligaments of patients with early-stage AS, and cartilage formation was followed by calcification. Moreover, a large number of giant osteoclasts were found in the inflammatory environment of ligaments and on bony surfaces of calcified cartilage. Resorption activity by these giant osteoclasts generated marrow with high levels of active TGF-β, which induced new bone formation in the ligaments. Notably, no Osterix+ osteoprogenitors were found in osteoclast resorption areas, indicating uncoupled bone resorption and formation. Even at the late and maturation stages, the uncoupled osteoclast resorption in bony interspinous ligament activates TGF-β to induce the progression of ossification in AS patients. Osteoclast resorption of calcified cartilage-initiated ossification in the progression of AS is a similar pathologic process of acquired heterotopic ossification (HO). Our finding of cartilage formation in the ligaments of AS patients revealed that the pathogenesis of spinal fusion is a process of HO and explained why anti-inflammatory treatments do not slow ankylosing once there is new bone formation in spinal soft tissues. Thus, inhibition of HO formation, such as osteoclast activity, cartilage formation, or TGF-β activity could be a potential therapy for AS. [ABSTRACT FROM AUTHOR]

The current study validated the Math Homework Purpose Scale (MHPS) for preadolescents. Having randomly split participants into two subsamples, we conducted exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) on subsample 1 (n = 293) and subsample 2 (n = 292), respectively. Both EFA and CFA indicated that the MHPS consisted of three factors: Academic, Self-regulatory, and Approval-seeking Reasons. Given an adequate level of measurement invariance, we further examined the latent mean difference across gender. Results revealed no statistically significant mean differences in Academic, Self-regulatory, and Approval-seeking Reasons across gender. Finally, consistent with theoretical expectations, Academic and self-regulatory Reasons were positively correlated with homework effort, homework completion, and math achievement. [ABSTRACT FROM AUTHOR]

To assess the effectiveness of tricortical iliac crest allografts with anterolateral instrumentation after single-stage surgery for thoracic and lumbar spinal tuberculosis (TB). Fifty-six patients with thoracic and lumbar spinal TB underwent single-stage anterior radical debridement, interbody fusion with tricortical iliac crest allografts and anterolateral single rod instrumentation. All patients were given 18 months of antituberculosis chemotherapy. The patients were followed up regularly, and their clinical manifestations, roentgenogram results, erythrocyte sedimentation rate (ESR) and liver function test were the results to be concerned. Radiographs were analysed before surgery, immediately after surgery, and at the final follow-up examination. Mean follow-up period was 37.5 months in 52 patients, and 4 patients were lost to follow-up. No patients had superficial wound infections, and all the incisions healed within 2 weeks. No graft fracture, collapse, or sliding was observed. The average bony fusion time was 10.6 months. Bony fusion was observed in all 52 patients within 18 months. The average degrees of kyphotic correction loss for thoracic and lumbar spine were 6.71° and 2.78° respectively. Although it took a long time to achieve solid fusion, tricortical iliac crest allografts were found to be convenient and safe to be used in spinal TB surgery. They may be effective options for interbody fusion, deformity correction and correction maintenance with anterolateral single rod instrumentation. [ABSTRACT FROM AUTHOR]

With the rapid depletion of crude resources, microorganism lipids have started attracting increasing attention because of their renewable qualities. However, their production is limited by high costs. In this study, we aimed to reduce the production cost of Sporidiobolus pararoseus JD-2 lipid by co-producing extracellular polysaccharide (EPS) and single-cell protein (SCP). In batch fermentation, the yields of lipid, EPS and SCP under ammonia nitrogen limitation increased by 20.3%, 32.0% and 43.7%, respectively, compared with the yields in the control group (without NH4+). Next, fed-batch fermentation was performed under different ammonia nitrogen levels. The yield, productivity and coefficient of lipid reached 47.1 ± 1.1 g/L, 0.66 g/L/h and 0.250 g/g, respectively, under an ammonia nitrogen level of 20 g/L (NH4)2SO4. In the same process, 14.3 ± 1.6 g/L EPS and 12.7 ± 0.8 g/L SCP were also obtained. Nutrient analysis of the product revealed that NH4+ affected the proportion of pigments in the carotenoids and increased the content of unsaturated fatty acids in the lipid; EPS mainly comprised galactose, glucose, mannose and fucose, at a ratio of approximately 45:37:2:1; and the essential amino acid content in SCP accounted for 48% of the product. Thus, this study provided a new strategy for improving S. pararoseus JD-2 lipid production at a lower cost. [ABSTRACT FROM AUTHOR]

Lysine is widely used in food, medical and feed industries. The biosynthesis of l-lysine is closely related to NADPH level, but the regulation mechanism between the biosynthesis of l-lysine in C. glutamicum and the cofactor NADPH is still not clear. Here, a high intracellular NADPH level strain C. glutamicum XQ-5Δpgi::(zwf-gnd) was constructed by blocking the glycolytic pathway and overexpressing the pentose phosphate pathway in the lysine-producing strain C. glutamicum XQ-5, and the intracellular NADPH level in strain XQ-5Δpgi::(zwf-gnd) was increased from 3.57 × 10–5 nmol/(104 cells) to 1.8 × 10–4 nmol/(104 cell). Transcriptome analyses pointed to Cgl2680 as an important regulator of NADPH levels and l-lysine biosynthesis in C. glutamicum. By knocking out the gene Cgl2680, the intracellular NADPH level of the recombinant C. glutamicum lysCfbr ΔCgl2680 was raised from 7.95 × 10–5 nmol/(104 cells) to 2.04 × 10–4 nmol/(104 cells), consequently leading to a 2.3-fold increase in the NADPH/NADP+ ratio. These results indicated that the regulator Cgl2680 showed the negative regulation for NADPH regeneration. In addition, Cgl2680-deficient strain C. glutamicum lysCfbr ΔCgl2680 showed the increase of yield of both l-lysine and l-leucine as well as the increase of H2O2 tolerance. Collectively, our data demonstrated that Cgl2680 plays an important role in negatively regulating NADPH regeneration, and these results provides new insights for breeding l-lysine or l-leucine high-yielding strain. [ABSTRACT FROM AUTHOR]

The metamorphism of snow (snowmelt process) has a potential influence on chemical and physical process occurring within it. This study carried out a detailed study on the variation of dissolved organic matter (DOM) in different stages of snowmelt in a typical mountain glacier located at Tibetan Plateau through collecting four different surface snow/ice categories, i.e., fresh snow, fine firn, coarse firn, and granular ice during May to October in 2015. The dissolved organic carbon (DOC) was observed by lost 44% from fresh snow to fine firn and enriched 129% from fine firn to granular ice, reflecting the dynamic variability in DOC concentration during snow metamorphism. The absorbance properties of each snow category are positively correlated with DOC concentration. The result of excitation emission matrix fluorescence with parallel factor analysis (EEM-PARAFAC) and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) highlighted the domination of lipid- and protein-like compounds in glacial-derived DOM. The molecular composition of the DOM also exhibited a new N-containing molecular formula (CHON classes) that was enriched during snow metamorphism. This study suggests that snow metamorphism could induce a loss of DOM as well as enrich and modify the DOM. [ABSTRACT FROM AUTHOR]

Emotion management is an important component under the self-regulated learning model, and teachers' emotion management plays an essential role in their technology integration into teaching practices. The current study investigated models of teachers' emotion management while learning and using information technology, using data from 866 teachers from 58 kindergartens in China. Results from multilevel analysis revealed that at the individual level, emotion management was positively related to monitoring motivation, managing time, arranging the environment, mastery orientation, and help seeking. Meanwhile, emotion management was negatively related to avoidance orientation. In addition, compared with young teachers, older teachers were less likely to take initiatives to manage emotion. At the kindergarten level, emotion management was negatively related to avoidance orientation. These findings were discussed with theory and research in related fields, and implications were drawn in terms of adding the self-regulated learning strategies in the professional trainings and increasing teachers' awareness to apply self-regulation strategies. [ABSTRACT FROM AUTHOR]

The current study evaluated the psychometric properties of the Teacher Homework Involvement Scale (THIS) for undergraduates in online environments. Based on a randomized divided sample, we carried out CFA with Group 1 (n = 306) and Group 2 (n = 306), respectively. CFA findings from both groups indicated that THIS contained three factors: Homework Quality, Autonomy Support, and Feedback Quality. Results further revealed that there was measurement invariance between these two groups. In addition, our findings revealed that latent factor means were invariant across gender for both groups combined. Furthermore, the THIS showed very good to excellent reliability. Finally, consistent with theoretical expectations, the THIS was positively associated with desirable behaviors regarding online homework assignments (effort, time management, and completion), online course quality, and online course satisfaction. [ABSTRACT FROM AUTHOR]

A nanorod-structured strontium hydroxystannate [SrSn(OH)6] flame retardant was synthesized via a facile coprecipitation method and employed in epoxy resin (EP). Based on X-ray diffraction analysis, scanning electron microscopy, and transmission electron microscopy, the as-synthesized SrSn(OH)6 nanorods exhibited high crystallinity and uniform size distribution. The flame retardancy and smoke suppression properties of EP/SrSn(OH)6 composites were investigated by limiting oxygen index and cone calorimetry tests. The results showed that incorporation of SrSn(OH)6 led to a dramatic reduction of the fire hazards of EP, including a 21.9% maximum decrease in the peak heat release rate, a 33.3% reduction in the toxic CO yield, and a 133.3% increase in the char residue. In particular, this is the first attempt to evaluate the flame retardancy properties of SrSn(OH)6 nanorods in EP. The improved flame retardancy properties of the SrSn(OH)6 nanorods is attributed to their catalytic carbonization effect. [ABSTRACT FROM AUTHOR]

The synergistic flame-retardant and smoke suppression properties of ammonium polyphosphate (APP) and activated carbon-supported Fe2O3 (AC-Fe2O3) on flame-retardant epoxy resin (EP) composites were studied. The fire behavior and smoke emission of EP composites were evaluated by limiting oxygen index (LOI), scanning electron microscopy, UL-94 vertical burning, and cone calorimeter test. LOI and UL-94 tests showed that the addition of appropriate amount of AC-Fe2O3 can effectively reduce the fly ash phenomenon, the dripping, and after-flame time. The thermogravimetric analysis and derivative thermogravimetry results showed that APP and AC-Fe2O3 can effectively decrease the maximum decomposition rate (Rmax) and promote the carbonization reaction of EP. As for the cone calorimeter test results, APP and AC-Fe2O3 clearly changed the decomposition behavior of EP, leading to the formation of a stable char layer on the surface of the composites. When flame-retardant loading was 4 mass%, the peak heat release rate and peak smoke production rate of the 3APP/1AC-Fe2O3/EP sample decreased 50.2% and 46.9%, respectively. The amount of char residual after test increased from 8.47 to 21.25%. In addition, it was observed from the macroscopic photographs of the char residue after the cone test that, at the optimum proportion, APP and AC-Fe2O3 could promote the formation of compact charred layers and prevent their cracking, which effectively protected the underlying materials from burning. [ABSTRACT FROM AUTHOR]

The present study validated the Expectancy Value Scale (EVS) for teachers regarding information technology. Participants were 866 teachers from 58 kindergartens in China. Based on a randomly split sample, we used one half (n = 433) for exploratory factor analysis, and anther half (n = 433) for confirmatory factor analysis. Both EFA and CFA results revealed that Expectancy and Value were distinguishable. Furthermore, latent factor means for the EVS were invariant across age (less than 30 years vs. 30 years and more) and education level (high school vs. bachelor's or beyond). Finally, consistent with theoretical expectations, the EVS was negatively correlated with distractions while learning and applying information technology. [ABSTRACT FROM AUTHOR]

A new-type multiple-source heat pump cycle with two-stage compression was established on the basis of the problems of similarly existing heat pumps. The equivalent temperature levels of typical evaporators are applied to the different heat sources of the proposed cycle, and the high-temperature heat sources are shown to enhance vapor injection. Then, the mathematical model and prototype are developed, and the results from experimental simulation and validation showed that the solar collector can improve the heating performance of the proposed heat pump system. In the middle-temperature heating period, the outdoor temperature is less than −25°C, and the average coefficient of performance (COP) value of the proposed heat pump was 4.2, which was greater than the COPs of conventional ground source heat pumps. [ABSTRACT FROM AUTHOR]

This study examines factors related to student self-efficacy beliefs in on-line groupwork. Participants in this study were 204 graduate students taking an online graduate-level course from a public university in the Southeast United States of America. Two-level hierarchical linear models were used to examine predictors of the students' self-efficacy. Three student-level variables were found to be related to groupwork self-efficacy: individual's willingness to handle groupwork challenge, trust relationship, and leadership influence. At the group level, the group's willingness to handle groupwork challenge was positively related to individual student's groupwork self-efficacy. Discussions of the findings suggest that leadership is important for groupwork. Instructors of online courses are recommended to design high-quality group projects that are purposeful, meaningful, challenging, and engaging. Communications between group members are also recommended to build trust. Implications of the findings to online learning and instruction as well as directions for future research are presented. [ABSTRACT FROM AUTHOR]

A phosphorous–nitrogen containing cyclophosphazene derivative intumescent flame retardant with branched structures, named six(1-oxo-2,6,7-trioxa-1-phosphabicyclo[2,2,2]octane-4-methyl) cyclotriphosphazene (PEPAP), was synthesized by introducing caged phosphate to cyclotriphosphazene backbone. Then the PEPAP was applied to polypropylene (PP) by melt blending to improve the flame retardancy and thermal stability. Fourier transform infrared spectroscopy and proton nuclear magnetic resonance (1HNMR) were used to confirm the chemical structure of PEPAP. Thermal stability and flammability properties of PEPAP and PEPAP/PP composites were investigated by thermogravimetric analysis, limited oxygen index (LOI), vertical burning test (UL-94) and cone calorimetry tests. The flame-retardant mechanism was explored by thermogravimetric analysis/infrared spectrometry and thermogravimetry/mass spectrum analysis. The results showed that PEPAP had high thermal stability, and the addition of PEPAP greatly enhanced the carbonization process of PP. Also, the addition of PEPAP can dramatically improve the LOI value and UL 94 rating. For the 25% PEPAP/PP sample, the LOI value was increased to 29.4% and it can pass UL 94 V-0. The intumescent chars with an intact, multicellular structure formed from PEPAP/PP composites contain polyphosphoric acid, indicating a condensed flame-retardant mechanism of PEPAP. [ABSTRACT FROM AUTHOR]

Dragonfly algorithm (DA) is a new optimization technique based on swarm intelligence. DA simulates the static and dynamic swarming behaviors of dragonflies in nature. The search pattern of DA consists of two essential phases: exploration and exploitation that are inspired by the survival rule of dragonflies in navigating, searching for food and fleeing enemies when dynamically or statistically swarming. This method is straightforward to implement and is efficient in solving real-world problems. However, an excessive number of social interactions in DA may result in low solution accuracy, easy stagnation at local optima and an imbalance between exploration and exploitation. To overcome these deficiencies, an improved Nelder-Mead algorithm is added to the conventional DA (INMDA) to strengthen its local explorative capability and avoid the possibility of falling into local optima. Simulation experiments were conducted on several well-known benchmark functions with different dimensions. In addition, the three classic classification problems are utilized to benchmark the performance of the proposed algorithm in training a multilayer perceptron. The experimental results and statistical significance show that the performance of the proposed INMDA is superior to that of the other algorithms. [ABSTRACT FROM AUTHOR]