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With regard to retired LiFePO4 batteries, resource treatment has become a matter of public concern. The currently used wet recycling process causes secondary environmental pollution and has the difficulty of full-component recovery. Therefore, a green and efficient recovery process for the realization of full-component recovery of LiFePO4 black powder is proposed in this work. In this closed-loop process with liquid flow circulation, no waste liquid and gas emission is generated, and the purity of recycled Li2CO3 can reach up to 99.4%. Moreover, battery-grade FePO4 can be obtained after simple treatment, solving the problem of lithium tailings and slag in the traditional wet recycling process. The performances of recycled Li2CO3 and FePO4 are similar to commercialization products according to electrochemical tests. More importantly, the resynthesized LiFePO4 cathode displays high-capacity retention of 97.5% after 200 cycles at 0.5 C, indicating the superiority of our strategy. Furthermore, the pouch cell with 5.2 A h presents outstanding performance, and high-capacity retentions of 96% and 95.2% can be observed after 500 cycles at 0.5 C and 1 C, respectively. The aforementioned results indicate the attractive prospects of this green and efficient lithium extraction and full-component recovery process. [ABSTRACT FROM AUTHOR]

This paper is concerned with the stochastic optimal control problem of a 1-dimensional McKean–Vlasov stochastic differential equation (SDE) with reflection, of which the drift coefficient and diffusion coefficient can be both dependent on the state of the solution process along with its law and control. One backward stochastic partial differential equation (BSPDE) with the Neumann boundary condition can represent the value function of this control problem. Existence and uniqueness of the solution to the above equation are obtained. Finally, the optimal feedback control can be constructed by the BSPDE. [ABSTRACT FROM AUTHOR]

Aims: To analyse spatial and temporal changes in the global burden of diabetes mellitus (DM) attributable to dietary factors from 1990 to 2019. Materials and Methods: The burden of DM was analysed in terms of age‐standardized disability‐adjusted life‐year (DALY) rates and age‐standardized death rates (ASDRs), which were obtained from the Global Burden of Disease Study 2019, and their corresponding estimated annual percentage changes (EAPCs). Results: The ASDR exhibited a decreasing trend (EAPC = −0.02), while the age‐standardized DALY rate exhibited an increasing trend (EAPC = 0.65). Forty‐four percent of the burden of DM was attributable to dietary factors, with the three largest contributors being high intake of red meat, high intake of processed meat, and low intake of fruit. Residence in a region with a high sociodemographic index (SDI) was associated with a diet low in whole grains and high in red meat and processed meat, while residence in a low‐SDI region was associated with a diet low in whole grains and fruits, and high in red meat. Conclusions: The age‐standardized DALYs of DM attributable to dietary factors increased between 1990 and 2019 but differed among areas. The three largest dietary contributors to the burden of DM were high intake of red meat, high intake of processed meat, and low intake of fruit. [ABSTRACT FROM AUTHOR]

Music has become a common adjunctive treatment for Alzheimer's disease (AD) in recent years. Because Alzheimer's disease can be classified into different degrees of dementia according to its severity (mild, moderate, severe), this study is to investigate whether there are differences in brain response to music stimulation in AD patients with different degrees of dementia. Seventeen patients with mild-to-moderate dementia, sixteen patients with severe dementia, and sixteen healthy elderly participants were selected as experimental subjects. The nonlinear characteristics of electroencephalogram (EEG) signals were extracted from 64-channel EEG signals acquired before, during, and after music stimulation. The results showed the following. (1) At the temporal level, both at the whole brain area and sub-brain area levels, the EEG responses of the mild-to-moderate patients showed statistical differences from those of the severe patients (p < 0.05). The nonlinear characteristics during music stimulus, including permutation entropy (PmEn), sample entropy (SampEn), and Lempel–Ziv complexity (LZC), were significantly higher in both mild-to-moderate patients and healthy controls compared to pre-stimulation, while it was significantly lower in severe patients. (2) At the spatial level, the EEG responses of the mild-to-moderate patients and the severe patients showed statistical differences (p < 0.05), showing that as the degree of dementia progressed, fewer pairs of EEG characteristic showed significant differences among brain regions under music stimulation. In this paper, we found that AD patients with different degrees of dementia had different EEG responses to music stimulation. Our study provides a possible explanation for this discrepancy in terms of the pathological progression of AD and music cognitive hierarchy theory. Our study has adjunctive implications for clinical music therapy in AD., potentially allowing for more targeted treatment. Meanwhile, the variations in the brains of Alzheimer's patients in response to music stimulation might be a model for investigating the neural mechanism of music perception. [ABSTRACT FROM AUTHOR]

Objective To develop a short-term renal outcome prediction model for acute kidney injury (AKI) in patients with LN. Methods Two lupus AKI cohorts from two independent centres during 2013–2019 were included: a derivation cohort from a rheumatology centre and a validation cohort from a nephrology centre. Clinical characteristics and renal histologic features were obtained. The outcome measurement was the recovery of kidney function within 12 months. Lasso regression was used for feature selection. Prediction models with or without pathology were built and a nomogram was plotted. Model evaluation including calibration curve and decision curve analysis was performed. Results A total of 130 patients were included in the derivation cohort and 96 patients in the validation cohort, of which 82 and 73 patients received a renal biopsy, respectively. The prognostic nomogram model without pathology included determinants of SLE duration, days from AKI onset to treatment and baseline creatinine level [C-index 0.85 (95% CI 0.78, 0.91) and 0.79 (95% CI 0.70, 0.88) for the two cohorts]. A combination of histologic tubulointerstitial (TI) fibrosis in the nomogram gave an incremental predictive performance (C-index 0.93 vs 0.85; P  = 0.039) in the derivation cohort but failed to improve the performance in the validation cohort (C-index 0.81 vs 0.79; P  = 0.78). Decision curve analysis suggested clinical benefit of the prediction models. Conclusion The predictive nomogram models might facilitate more accurate management for lupus patients with AKI. [ABSTRACT FROM AUTHOR]

Purpose: Rapid prototyping (RP) technology is widely used in many fields in recent years. Bone tissue engineering (TE) is an interdisciplinary field involving life sciences, engineering and materials science. Hydroxyapatite (HAp) are similar to natural bone and it has been extensively studied due to its excellent biocompatibility and osteoconductivity. This paper aims to review nanoscaled HAp-based scaffolds with high porosity fabricated by various RP methods for bone regeneration. Design/methodology/approach: The review focused on the fabrication methods of HAp composite scaffolds through RP techniques. The paper summarized the evaluation of these scaffolds on the basis of their biocompatibility and biodegradability through in vitro and in vivo tests. Finally, a summary and perspectives on this active area of research are provided. Findings: HAp composite scaffold fabricated by RP methods has been widely used in bone TE and it has been deeply studied by researchers during the past two decades. However, its brittleness and difficulty in processing have largely limited its wide application in TE. Therefore, the formability of HAp combined with biocompatible organic materials and fabrication techniques could be effectively enhanced, and it can be used in bone TE applications finally. Originality/value: This review paper presented a comprehensive study of the various types of HAp composite scaffold fabricated by RP technologies and introduced their potential application in bone TE, as well as future roadmap and perspective. [ABSTRACT FROM AUTHOR]

This study proposes an exotic option that extends the classical European option by requiring option holders to continuously trade in underlying assets according to a predesignated trading strategy with a general logarithmic position. The pricing formula for the exotic option with a general logarithmic strategy is derived from the Black–Scholes option pricing formula, and its price advantage is compared (based on simulations) to the classical European option and to the exotic option with a linear position. By varying key parameters, we found that the exotic option with a general logarithmic position has a significant price advantage (up to 34% under certain parameter settings) over the classical European option. Moreover, the exotic option with a general logarithmic strategy can save 5.5% more of the option premium than applying a linear position strategy. Our simulation results indicate that the price advantage of this proactive hedging option with a general logarithmic strategy depends heavily on the initial amount of capital; in particular, this exotic option is more suitable for traders with limited initial amounts of capital. [ABSTRACT FROM AUTHOR]

Background: Diabetic nephropathy (DN) is one of the most serious microvascular complications of diabetes, valsartan and α-lipoic acid alone or in combination has been used for the treatment of patients with DN. However, some results in these clinical reports were still controversial. The purpose of this study was to evaluate the efficacy of valsartan combined with α-lipoic acid on renal function in patients with DN. Methods: We searched the electronic databases including PubMed, Sciencedirect, EMBASE, Cochrane library, Chinese national knowledge infrastructure (CNKI) and Wanfang databases, and the publication deadline was limited to January 2020. Randomized controlled trials (RCTs) evaluating the effects of valsartan combined with α-lipoic acid in DN patients were included. Pooled estimates were conducted using a fixed or random effect model. The outcomes included urinary albumin excretion rate (UAER), and the level of urinary albumin, β2-microglobulin (β2-MG), hypersensitive C-reactive protein (hs-CRP) and oxidative stress. Results: 11 studies with 1294 participants were included in this study. The pooled analysis indicated that α-lipoic acid combined with valsartan could remarkably reduce UAER (P < 0.00001, SMD = -1.95, 95%CI = -2.55 to − 1.20; P = 0.03, SMD = -0.85, 95%CI = -1.59 to − 0.1) and the level of urinary albumin (P = 0.001, SMD = -1.48, 95%CI = − 2.38 to − 0.58; P = 0.01, SMD = -1.67, 95%CI = -3.00 to − 0.33), β2-MG (P < 0.001,SMD = − 2.59, 95%CI = -3.78 to − 1.40; P = 0.03, SMD = -0.48, 95%CI = -0.93 to − 0.04) when compared with valsartan or lipoic acid monotherapy in patients with DN. However, there was no significant difference in the level of hs-CRP among the three therapies (P = 0.06, SMD = -2.80, 95%CI = -5.67 to 0.07; P = 0.10, SMD = -0.42, 95%CI = − 0.92 to 0.08). In addition, α-lipoic acid combined with valsartan markedly increased the level of SOD (P = 0.03, SMD = 1.24, 95%CI = 0.32 to 1.03; P = 0.0002, SMD = 0.68, 95%CI = 0.32 to 1.03) and T-AOC (P < 0.00001, SMD = 0.89, 95%CI = 0.62 to 1.16; P = 0.02, SMD = 0.58, 95%CI = 0.10 to1.07), and reduced the level of MDA(P = 0.0002, SMD = -1.99, 95%CI = -3.02 to − 0.96; P = 0.0001, SMD = -0.69, 95%CI = -1.04 to − 0.34). Conclusions: α-lipoic acid combined with valsartan could significantly reduce the level of urinary albumin and oxidative stress, increase antioxidant capacity and alleviate renal function damage in patients with DN, and this will provide a reference for the selection of treatment drugs for DN. [ABSTRACT FROM AUTHOR]

Immune thrombocytopenia (ITP) is a common complication of connective tissue diseases (CTD). However, refractory and recurrent cases are frequent, who often need intensive immunotherapy. In the real world to compare the efficacy and safety of two common options, rituximab (RTX) and cyclosporine (CsA), in patients with refractory CTD-ITP, we conducted this retrospective study. Inpatients diagnosed with CTD-ITP who experienced treatment failure with initial prednisone or other immunosuppressants and who subsequently received either RTX or CsA between 2013 and 2018 were identified. All the patients were followed up for at least 6 months. Remission was defined as sustained platelet count ≥ 50 × 10^9/L, where ≥ 100 × 10^9/L was considered complete remission and 50–100 × 10^9/L was considered partial remission. Propensity score weighting analysis was performed to balance the confounders as indication. A total of 83 patients with CTD-ITP were identified, of whom 43 had systemic lupus erythematosus, 24 had undifferentiated CTD, and 16 had primary Sjogren syndrome. The RTX group (n = 53) had a much higher remission rate than the CsA group (n = 30) after 3 months and throughout the following 3 months (3 m, 86.8% vs 63.6%, p = 0.025; 6 m, 81.8% vs 53.5%, p = 0.011). Binary logistic regression analysis confirmed that treatment with RTX predicted better outcome (OR 4.09, 1.42 ~ 11.79), while age > 50 (OR 0.31, 0.11 ~ 0.93) was a risk factor. Furthermore, we reinforced the conclusions by propensity score weighting analysis (RTX OR 4.89, 1.64 ~ 14.58; age > 50 OR 0.31, 0.12 ~ 0.83). In our real-world retrospective study, for patients with refractory CTD-ITP, RTX was superior to CsA in terms of the durable remission rate. Key Points: • Refractory cases are common in patients with immune thrombocytopenia secondary to connective tissue diseases (CTD-ITP), requiring intensive immunotherapy. • Randomized controlled trials comparing rituximab and a traditional immunosuppressive agents (IS), such as cyclosporin, are lacking in these patients. • Our real-word retrospective study indicated that rituximab was superior to cyclosporin in patients with refractory CTD-ITP. [ABSTRACT FROM AUTHOR]

Objective. To identify susceptibility modules and genes for cardiovascular disease in diabetic patients using weighted gene coexpression network analysis (WGCNA). Methods. The raw data of GSE13760 were downloaded from the Gene Expression Omnibus (GEO) website. Genes with a false discovery rate < 0.05 and a log2 fold change ≥ 0.5 were included in the analysis. WGCNA was used to build a gene coexpression network, screen important modules, and filter the hub genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed for the genes in modules with clinical interest. Genes with a significance over 0.2 and a module membership over 0.8 were used as hub genes. Subsequently, we screened these hub genes in the published genome-wide SNP data of cardiovascular disease. The overlapped genes were defined as key genes. Results. Fourteen gene coexpression modules were constructed via WGCNA analysis. Module greenyellow was mostly significantly correlated with diabetes. The GO analysis showed that genes in the module greenyellow were mainly enriched in extracellular matrix organization, extracellular exosome, and calcium ion binding. The KEGG analysis showed that the genes in the module greenyellow were mainly enriched in antigen processing and presentation, phagosome. Fifteen genes were identified as hub genes. Finally, HLA-DRB1, LRP1, and MMP2 were identified as key genes. Conclusion. This was the first study that used the WGCNA method to construct a coexpression network to explore diabetes-associated susceptibility modules and genes for cardiovascular disease. Our study identified a module and several key genes that acted as essential components in the etiology of diabetes-associated cardiovascular disease, which may enhance our fundamental knowledge of the molecular mechanisms underlying this disease. [ABSTRACT FROM AUTHOR]

With the increasing rate of chemoresistance in colorectal cancer (CRC) patients with advanced tumor stages, it is a matter of urgent importance to delineate the factors involved in the drug resistance process. In this study, gene expression profiles were downloaded from the Gene Expression Omnibus database and an integrated analysis with the aim of detecting hub long non-coding RNAs (lncRNAs) and their regulated, differentially expressed genes (DEGs) during treatment with oxaliplatin (OxPt) or irinotecan was conducted. A total of seven differentially expressed lncRNAs were correlated with OxPt resistance and 21 were correlated with resistance to SN-38, the active metabolite of irinotecan. Gene Ontology annotation and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis confirmed that drug resistance was strongly associated with an imbalance between cell proliferation and apoptosis, cell energetic metabolism under hypoxic conditions, and angiogenesis. Moreover, a large number of lncRNA-targeted DEGs were located in extracellular exosomes. Further analyses identified four hub lncRNAs involved in the process of drug resistance, including CRNDE, H19, UCA1 and HOTAIR, which are predictive factors for treatment sensitivity. Among them, HOTAIR stands out as a strong factor, the elevated expression of which is also associated with advanced tumor node and metastasis stage and poor CRC disease prognosis. [ABSTRACT FROM AUTHOR]

In the multi-attribute decision-making problems, uncertain information can be well-represented by single-valued neutrosophic linguistic sets (SVNLSs); Decision makers' risk attitudes toward gains and losses can be solved by prospect theory (PT). Based on both, a novel integrated fuzzy decision method is proposed which combines SVNLS and PT (SVNLS-PT). In this method, we extend linguistic scale function to adapt the single-valued neutrosophic linguistic environment. Following that, we introduce the operational laws, some aggregation operators and the distance calculating method of SVNLS. Besides, PT is employed to rank the alternatives. In order to reflect both subjective considerations of decision makers and objective information, weights of attributes are combined by objective weights and subjective weights which objective weights are obtained by mean-squared deviation method and subjective weights by establishing the liner programing model. Finally, a case study concerning investment project of Internet of Vehicles is provided to illustrate the applicability of the proposed method. [ABSTRACT FROM AUTHOR]

Background: The primary aim of this research was to examine the role of psychological empowerment on the work engagement of university faculty members in China and the implications for both faculty members and university administrators. The questions of the study focus on the level of psychological empowerment and work engagement of university faculty members and the correlation between psychological empowerment and work engagement. Materials and methods: Data were collected from a sample of 162 faculty members working at a China university. They were asked to complete two self-reported scales with good reliability and validity: the psychological empowerment scale (PES) and the Utrecht work engagement scale (UWES). The responses from the sample were analyzed using SPSS software. The descriptive statistics showed the participants' statistical characteristics, while independent sample t-tests and one-way analysis of variance (ANOVA) revealed group differences among university faculty members. Correlation analysis and multidimensional regression analysis demonstrated how psychological empowerment affected work engagement. Results: The total scores for the PES and UWES were both moderately high. Gender, age, degree attained, and professional ranking were associated with differences in levels of psychological empowerment and work engagement. The results confirmed that psychological empowerment was positively correlated with all the dimensions of work engagement. The regression analysis results showed that the positive role of psychological empowerment in work engagement was mainly realized through two dimensions: meaning and competence. Conclusion: The study results revealed significant group differences in the PES and UWES scores among university faculty members. Universities should give more support to younger and junior faculty. There is highly positive correlation between psychological empowerment and work engagement. University should recognize the role of psychological empowerment and create a supportive environment to promote faculty members' professional development, which, in turn, can increase universities' productivity. [ABSTRACT FROM AUTHOR]

Aqueous supercapacitors have occupied a significant position among various types of stationary energy storage equipment, while their widespread application is hindered by the relatively low energy density. Herein, N/F co-doped carbon materials activated by manganese clusters (NCM) are constructed by the straightforward experimental routine. Benefiting from the elevated conductivity structure at the microscopic level, the optimized NCM-0.5 electrodes exhibited a remarkable specific capacitance of 653 F g−1 at 0.4 A g−1 and exceptional cycling stability (97.39% capacity retention even after 40,000 cycles at the scanning rate of 100 mV s−1) in a neutral 5 M LiCl electrolyte. Moreover, we assembled an asymmetric device pairing with a VOx anode (NCM-0.5//VOx), which delivered a durable life span of 95% capacity retention over 30,000 cycles and an impressive energy density of 77.9 Wh kg−1. This study provides inspiration for transition metal element doping engineering in high-energy storage equipment. [ABSTRACT FROM AUTHOR]

With the rapid increase in the usage of lithium ion batteries, recovering Li 2 CO 3 from LiFePO 4 black powder has become an issue of public concern. Nowadays, the widely used acid leaching technology has some obvious disadvantages, such as complex recovery process, serious equipment corrosion and unavoidable secondary pollution. In this work, a novel acid-free leaching route of recovering Li 2 CO 3 and FePO 4 from LiFePO 4 black powder is proposed. This novel route does not include inorganic or organic acid leaching, complex pH adjustment and wastewater treatment processes. After optimizing the technological conditions, Li 2 CO 3 and FePO 4 with high purity are recovered with high recovery rate of over 96%. Then, the recovered Li 2 CO 3 and FePO 4 are used as iron and lithium sources to regenerate LiFePO 4 and the electrochemical performances are compared in detail. When the molar ratio of Li 2 CO 3 :FePO 4 :C 6 H 12 O 6 (glucose) is 1.03:2:0.35, the regenerated LiFePO 4 (R-LFP-0.35) cathode displays the optimal electrochemical performance with the discharge capacity of 163.9 mAh g−1 at 0.1 C, 120 mAh g−1 at 4 C and excellent capacity retention ratio of 98.0% after 100 cycles at 0.2 C. This work provides a new green and environmentally friendly strategy for the recycling of LiFePO 4 black powder. • A novel acid-free leaching route of recovering Li 2 CO 3 and FePO 4 is proposed. • The closed-loop recycling route improves the recovery rate of Li 2 CO 3. • The recovered Li 2 CO 3 and FePO 4 are of high purity. • The regenerated LiFePO 4 cathode displays excellent electrochemical properties. [ABSTRACT FROM AUTHOR]

Activation of macrophages and overexpression of TNFα is associated with the pathogenesis of chronic inflammatory diseases. However, the mechanisms leading to TNFα overexpression are still unknown. 5-methylocytosine (5-mC) is an epigenetic modification that is associated with silenced genes. Recent studies showed that it is converted to 5-hydroxylmethylocytosine (5-hmC) and reactivates gene expression through the action of the family of Ten-Eleven-Translocation (TET1-3) enzymes. In this study, we show that 5-hmC levels are increased globally and specifically in the TNFα promoter during the differentiation of monocytes to macrophages. In addition, the levels of 5-hmC are increased upon LPS stimulation of macrophages. Furthermore, CRIPSR stable knockout of TET1 decreases the expression of TNFα and other pro-inflammatory cytokines. In conclusion, we showed that TET1 contributes to the activation of macrophages possibly through regulation of 5-hydroxymethylation in the promoter of pro-inflammatory cytokine genes. The TET1 enzyme could be a promising therapeutic target to inhibit the persistent inflammation caused by macrophages in chronic inflammatory diseases. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we compared the F2-Layer critical frequency (foF2) derived from FORMOSAT-3/COSMIC radio occultation (RO) and ionosondes at Chiang Mai, Chumphon and Kototabang during the years 2008–2015 to evaluate the performance of COSMIC RO over Southeast Asia region. The results show that the time development of foF2 values derived from COSMIC RO generally agrees well with those from ionosonde measurements. However, the differences between the foF2 derived from COSMIC RO and that derived from ionosonde observations display latitudinal dependence. COSMIC RO tends to underestimate foF2 at Chiang Mai and Kototabang, which is near to the north EIA crest and the south one, respectively, while a little overestimate foF2 at Chumphon, which is close to the geomagnetic equator. COSMIC RO agrees best with ionosonde at Chumphon and worst at Chiang Mai. At each ionosonde station, the quality of COSMIC RO data degrades with the increase of solar activity. In addition, at the station Chiang Mai and Kototabang, COSMIC RO performs better in summer than in equinox and winter. Furthermore, the differences in foF2 derived from COSMIC RO and that from ionosonde measurements vary with local time, i.e., the differences in foF2 are generally smaller at night and larger in noontime when equatorial ionization anomaly (EIA) is well developed. [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate the interrelationship between tooth preparation and dental structure of Chinese maxillary central incisors and provide scientific guidance for clinical all-ceramic restoration. Forty-five specimens of maxillary central incisors were fabricated by 3D printer based on data of Micro CT scanning. Subsequently, every three specimens from the same natural tooth were randomly divided into three groups (n = 15): porcelain veneer, all ceramic crown, and the blank control group. All the specimen teeth were prepared according to routine clinical criteria, reconstructed into 3D models and then measured in software. The results showed that the mean quantity of reduction (volume fraction) was (28.35 ± 4.37) % and (56.93 ± 3.47) % for porcelain veneer and all-ceramic crown, respectively. The bonding areas of different all-ceramic restorations were (128.85 ± 11.73) mm2 and (97.15 ± 9.98) mm2 for all-ceramic crown and porcelain veneer respectively. In porcelain veneer group, the area of enamel adhesive was (54.80 ± 12.70) mm2, and the area of dentin was (42.35 ± 9.62) mm2. As the results of the one-sample t test, the mean distances from medullary angle to incisal edge or adjacent surface have significant differences with the test value which was set as 0.5 (P < .05). The reduction of the tooth for porcelain veneer is less than that of ceramic crown and the cementation of porcelain veneer is mostly dependent on the conservation of the enamel during preparation. The region from mesial adjacent surface to mesiopulpal angle is prone to have the problem of medullary perforation. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the potential cytotoxicity of self-adhesive resin cements with or without light irradiation on human periodontal ligament fibroblasts (HPDLFs) in vitro. Three self-adhesive resin cements (RelyX U200, Maxcem Elite and Multilink Speed) were cured with light or not. Cured cements were stored at 37°C for 24 h in water or Dulbecco’s modified eagle medium (DMEM) medium. Their chromatographic analysis of water-based extract solution was made and then the DMEM-based extract solution was diluted in complete DMEM {1:5, 1:10, 1:20, 1:40, 1:80 (v/v)} for evaluating cell relative growth rate and cell apoptosis/necrosis rate of HPDLFs. The data was analyzed by one-way ANOVA and independent T test. Regardless of light irradiation, cell relative growth rate increased, and the apoptosis/necrosis rate of each resin cement decreased with the increase of gradient dilution. Regardless of gradient dilution, the cell relative growth rate and apoptosis/necrosis rate of RelyX U200 and Maxcem Elite with light irradiation were higher than those without light irradiation. Besides, without light irradiation, Multilink Speed showed higher cell relative growth rate and lower apoptosis/necrosis rate than other cements. Light irradiation and composition difference of self-adhesive resin cements could affect their cytotoxicity on HPDLFs. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has significantly influenced the global economy, international travel, global supply chains, and how people interact, and subsequently affect globalization in coming years. In order to understand the impact of COVID-19 on globalization and provide potential guidance to policymakers, the present study predicted the globalization level of the world average and 14 specific countries in scenarios with and without COVID-19 based on a new Composite Indicator method which contains 15 indicators. Our results revealed that the world average globalization level is expected to decrease from 2017 to 2025 under the scenario without COVID-19 by −5.99%, while the decrease of globalization under the COVID-19 scenario is predicted to reach −4.76% in 2025. This finding implies that the impact of COVID-19 on globalization will not be as severe as expected in 2025. Nevertheless, the downward trend of globalization without COVID-19 is due to the decline of the Environmental indicators, whereas the decline under the COVID-19 scenario is attributed to Economic aspects (almost −50%). The impact of COVID-19 on globalization varies across individual countries. Among the countries investigated, COVID-19 had a positive impact on the globalization of Japan, Australia, the United States, the Russian Federation, Brazil, India and Togo. In contrast, the globalization in the United Kingdom, Switzerland, Qatar, Egypt, China and Gabon are expected to decrease. The variation of impact induced by COVID-19 on those countries is attributed to the weighting of economic, environmental and political aspects of globalization is different across these countries. Our results can help governments take suitable measures to balance economic, environmental and political policies, which may better support their decision-making. [ABSTRACT FROM AUTHOR]

To get strong, stiff and light cylindrical shell, carbon fiber reinforced hierarchical Isogrid stiffened cylinder (HISC) was designed and fabricated. The cylinder has fractal stiffeners, including the first-order primary Isogrid stiffeners and the self-similar second-order sub-Isogrid stiffeners. The primary Isogrid has thick and high ribs and contains several sub-Isogrid cells whose rib is much thinner and lower. The primary Isogrid improves the bending rigidity of the cylindrical wall to resist the global instability while the sub-Isogrid improves the bending rigidity of the skin enclosed by the primary Isogrid to resist local buckling. The HISC was fabricated by filament winding method based on a silicone rubber mandrel with hierarchical grooves. Axial compression test was performed to reveal the failure mode. With hierarchical stiffeners, the cylinder balances the construction of the skin and the ribs and fails at material failure. Global instability and local buckling are both well restricted by the hierarchical stiffeners. [ABSTRACT FROM AUTHOR]

To get a strong, stiff and weight efficient cylindrical shell, carbon fiber reinforced corrugated-core sandwich cylinders (CSCs) were designed and made. The corrugated-core is made up of corrugated cylindrical shell and manufactured by mould hot pressing method. Split forming and integral filament winding forming methods were applied to make the CSC separately. Effects from non-wrapped and wrapped cylindrical ends were investigated individually. Uniaxial compression tests were performed to reveal the strength and failure mode. Split forming method makes the CSC stiffer but integral filament winding forming method makes the CSC stronger. With non-wrapped ends, the cylinders fail at end delamination and the load carrying capacity is 289.7 kN and 373.7 kN, respectively. The load is improved to 415.6 kN and 491.4 kN, respectively, when the cylinder is end-wrapped. Skin fracture controls the failure of the CSCs with wrapped ends and makes them stronger. Meanwhile, the load carrying ability of the CSC is stronger than lattice truss-core sandwich cylinders (LTSCs). Benefiting from the high axial load carrying ability of the CFRC corrugated shell, strength of the designed CSC failing at skin fracture improves at a magnitude of 50% compared with the referenced LTSC. [ABSTRACT FROM AUTHOR]

The band-edge emission lifetime in a single ZnO tetrapod is studied by using the time-resolved confocal micro-photoluminescence (TR- μ PL) spectroscopic technique at room temperature. By performing μ PL and TR- μ PL mapping along the tapered arm of tetrapod, we observe whispering gallery mode (WGM) polaritons and find that the predominant radiative lifetime of exciton polaritons decreases linearly with increasing the surface-to-volume ratio of the sample. This behavior is ascribed to the surface electric field induced enhancement of the radiative decay rate of the exciton-like polaritons coupling with LO phonons. [ABSTRACT FROM AUTHOR]

Thrombotic microangiopathy (TMA) includes a series of life-threatening disorders. Systemic lupus erythematosus (SLE) is one of the most common acquired causes. To identify predictors of prognosis in patients with TMA secondary to SLE, we conducted a single-center historical study. From January 2013 to June 2016, of 2182 SLE hospitalized patients in the Ren Ji Hospital, a total of 21 consecutive patients with TMA secondary to SLE were identified. The 90-day short-term mortality was 33.3%. The kidney involvement (66.7%) was associated with poor prognosis, while the administration of rituximab ( n = 13) was an independent protective factor according to logistic regression analysis. Compared to conventional treatment, i.e., plasma exchange, high-dose glucocorticoids, and intravenous immunoglobulin, the overall survival is significantly higher among patients receiving rituximab add-on (92.2 vs 33.3%, p = 0.0173); however, five out of seven patients with renal involvement in the rituximab group were eventually hemodialysis dependent. Our data indicated that add-on rituximab in the background of conventional therapy may improve the overall but not the renal survival in SLE-TMA patients. [ABSTRACT FROM AUTHOR]

A theoretical study was carried out to predict the failure load and mode of composite anisogrid lattice sandwich cylinder (LSC) under fundamental loads. Four failure modes were suggested for this structure under axial compression, uniform external pressure and torsion, including global buckling, skin monocell buckling, rib crippling and strength failure. For each failure mode, the load capacity of the composite LSC was predicted theoretically and corrected by finite element method (FEM) with proper correction coefficients. To instruct the design of the LSC, failure mode maps were constructed, showing the dependence of failure mode and load on the geometrical variables of the lattice and skins. The concept of a failure mode map is extended to give a useful design tool for anisogrid sandwich cylinder manufacturers and their customers. [ABSTRACT FROM AUTHOR]

Under uniaxial compression, carbon fiber reinforced composite (CFRC) orthogrid sandwich cylinder has four potential failure modes, including global buckling, monocell buckling, rib buckling and material failure. The smearing method was applied to predict the equivalent stiffness and calculate the stresses of the skins and the orthogrid, providing fundaments to build the failure criteria. Theoretical models were established to reveal the failure modes and predict the ultimate load of the compressed orthogrid cylinder by the way of failure maps, providing a feasible way to optimally design CFRC anisogrid cylinder. [ABSTRACT FROM AUTHOR]

To construct weight efficient aerospace sandwich structures, interlocked orthogrid sandwich composite panels reinforced by carbon fibers were designed, made and tested. The orthogrid is weight efficient in flatwise compression for its strength is greater than usual three-dimensional (3D) lattice truss composite structures. Progressive crushing of the ribs endows the orthogrid long deformation plateau and great mean crushing force (MCF) while most of 3D lattice truss composite structures are usually brittle. Crushing models of lattice truss materials were developed to predict the MCF and it is found that the orthogrid composite has comparable or even better specific energy absorption (SEA) compared with 3D metallic lattice trusses. Forming continuous resin adhesive layers between the facesheets and the orthogrid, the orthogrid sandwich panel has stronger shear strength and is more weight efficient than usual 3D lattice truss sandwich panels jointed by adhesive joints in shear resistance. Through the research, it is concluded that interlocking orthogrid provides a simple but efficient way to construct lightweight sandwich composite. [ABSTRACT FROM AUTHOR]

To get a strong, stiff and weight efficient cylindrical shell, a carbon fiber reinforced orthogrid-core sandwich cylinder was designed and fabricated. The core is made up of orthogonal grids and manufactured by interlocking method. The sandwich cylinder is fabricated by filament winding method. Free vibration test combining with theoretical analysis and numerical simulation was carried out to reveal the vibration responses and estimate the modulus of the wound laminate. Uniaxial compression test was performed to reveal the strength and failure mode. Without end flanges, laminate delamination at the end controls the peak load. Delamination of skins induces interfacial debonding and dimpling of inner skin finally. An engineering method based on the average strain at the peak load is proposed to predict the load capacity of the cylinder. Compared with stiffened cylinder, the orthogrid sandwich cylinder is stiffer and stronger. Meanwhile, its making process is simplified and the mechanical ability is comparable with other lattice-core sandwich cylinders. [ABSTRACT FROM AUTHOR]

Extensional and in-extensional folding elements are two conventional plastic collapse mechanisms for thin-walled tubes to predict their anti-crushing behaviors. In the compression experiments of triangular tubes, a new folding element, named as inward-contracted folding element, was observed. Accompanying with this folding mechanism, double zigzags and half-shortened wavelength were observed in the corresponding deformation curve compared with the deformation curves of tubes collapsing at conventional modes. This inward-contracted folding element always follows behind the extensional folding to form a hybrid folding element. A plastic model was proposed, through which the mean crushing force (MCF) and the folding wavelength are predictable. [ABSTRACT FROM AUTHOR]

We prove an inequality for the geometric mean of accretive operators, where the geometric mean was brought in by Drury [Linear Multilinear Algebra. 2015;63:296–301]. The proof makes use of a result of Mathias [SIAM J. Matrix Anal. Appl. 1992;13:640–654]. This inequality is then used to clarify several plausible assertions. [ABSTRACT FROM AUTHOR]

• A unique information assimilation measure based on an IR platform. • More quality communications contribute to lower stock return synchronicity. • The effect is mostly due to increased firm-specific information instead of noise. • More quality communications has positive effect on investor reaction to news. In this paper, we employ a unique information assimilation measure for listed firms in China based on their communications with investors through an online platform designated by the China Securities Regulatory Commission (CSRC). We examine whether a firm's efforts in enhancing investors' information assimilation, such as providing more quality clarifications and explanations, helps facilitate the incorporation of firm-specific information in stock prices and reduces stock return synchronicity. We find robust evidence that more quality-clarifying communications contribute to lower stock return synchronicity after controlling for other information sources, and the decrease in synchronicity is mostly due to increased firm-specific information rather than noise. The causal relationship is established using a stacking DID approach and a PSM method. In a further analysis, we find that more quality communications can strengthen investors' reaction to good news and smooth their reaction to bad news. Our study provides direct evidence that enhanced information assimilation benefits firms by entrenching more firm-specific information into stock prices. [ABSTRACT FROM AUTHOR]

Hierarchical structures greatly enhance the anti-crushing behavior of thin-walled tubular structures. To reveal the hierarchical mechanism, hierarchical lattice tubes (HLTs) with lattice sandwich walls were designed and manufactured. In-plane compression experiments were carried out to reveal the progressive collapse modes and folding mechanisms. Compared with single-cell tubes (STs) and multi-cell lattice tubes (MLTs), HLTs possess much greater mean crushing forces (MCFs), three to five times higher. Two crushing mechanisms were revealed, including the hierarchical sandwich-folding mechanism and the multi-folding mechanism. Hierarchical sandwich-fold has much greater plastic bending moment while multi-fold has much shorter wave-length. Both these two mechanisms let hierarchical structure greatly improve its anti-crushing ability and weight efficiency in energy absorption. Theoretical models were proposed to predict the MCF and the specific energy absorption (SEA) of the HLT. These models are consistent with the test data and correctly reflect the energy absorbing ability of the HLT. [ABSTRACT FROM AUTHOR]

Hierarchy greatly enhances anti-crushing behavior of thin-walled tubular structures. To reveal the energy-absorbing mechanism, hierarchical triangular lattice structures with lattice-core sandwich walls were designed. Crushing experiments were carried out to reveal the progressive collapse modes and folding mechanisms. Compared with single-cell and multi-cell lattice structures, hierarchical structures possess greater mean crushing forces (MCFs), three to four times higher. Three mechanisms, including hierarchical folding, shortening wave length and enlarging plastic bending moment of sandwich wall, help hierarchical structure greatly enhance its anti-crushing behavior. Folding styles turning from single fold, multi-fold, hierarchical fold to single sandwich-fold when increasing micro-cells in the wall were revealed by numerical simulation to propose optimized hierarchical lattice structure possessing the best specific energy absorption (SEA). Based on progressive folding mechanism, global bending mechanism and hybrid folding mechanism, theoretical models were built to predict the MCF. The predictions are reasonable. [ABSTRACT FROM AUTHOR]

To improve the reutilization of advanced carbon fiber reinforced composite (CFRC) lattice-core sandwich cylinder (LSC), a severely damaged LSC was retrofitted by CFRC laminate through wrapping and riveting schemes. Free vibration and uniaxial compression experiments were carried out to reveal its mechanical performances. Natural frequencies and vibration modes of the repaired cylinder are close to the intact cylinder. Compared with the stiffness of the intact cylinder, 98.7 kN/mm, stiffness of the repaired cylinder is 138.83 kN/mm, even a little stiffer. Failure of the repaired cylinder locates at the lower end. Initially, the inner skin delaminated from the core and finally fracture of the outer skin made the cylinder out of work. The repaired segment is not damaged. Ultimate load of the repaired cylinder is 377.38 kN, only a little smaller than of the intact cylinder. The retrofitting scheme is effective to re-utilize the severally damaged CFRC LSC. [ABSTRACT FROM AUTHOR]

Discrete choice experiments are widely used in fields such as marketing, planning, transportation, and medical care to obtain information on consumer preferences. In such experiments, choice sets consisting of two or more profiles are presented to subjects, where a profile consists of a set of attributes (as a list or picture) which describe the product or process. Subjects are asked to select their most preferred profile from each choice set, and the importance of the attributes can be deduced from the choices made. This paper investigates locally A-optimal designs for estimating main effects of the attributes, together with their interactions, under the multinomial logit model. Lower bounds are derived for the average variance of any set of orthonormal contrasts of interest. A new approach is proposed for generating locally A-optimal or A-efficient designs. It is shown through examples that the new construction method enables highly efficient designs to be constructed without a complete search. [ABSTRACT FROM AUTHOR]

Pure chitosan and carbon nanotube (CNT)/chitosan nanocomposite films were fabricated via a sublimation-drying process at −196 °C, during which polymeric repulsion generates unique pores with multi-layered structures. The films were then transformed into multi-layered and vertically aligned multi-layered (VAM) structures by compression. Due to the cross-linking between layers, the films prepared at −196 °C showed significantly better mechanical properties than the films prepared at −78 and −20 °C. Furthermore, a peculiar phenomenon was observed in that pure chitosan which exhibited better mechanical properties than the nanocomposites. To explain these results, we suggest a model in which the VAM structure supports more load than the CNT fillers. [ABSTRACT FROM AUTHOR]

A new method of combined steam flash-explosion and alkaline treatment (SFE-AT) was developed to extract cellulose fibers from bark of cotton stalks, and lightweight composites with favorable properties were made from the obtained fibers and polypropylene (PP). It was reported that the cellulose fibers from bark of cotton stalks had higher mechanical properties than those from most lignocellulosic byproducts. However, conventional method of using strong alkaline condition (30–100 g/L NaOH) for extraction of cellulose fibers from lignocellulosic byproducts led to environmental pollution and high cost. In this study, bark of cotton stalks were treated using three methods, including alkaline treatment (AT), steam flash-explosion (SFE) and SFE-AT. The different cotton stalk fibers were blended with PP fibers and compression-molded into composites under optimized conditions (temperature of 170 °C, pressure of 3 MPa, 4 min). The results showed that PP composites reinforced by cotton stalk fibers from SFE-AT had the best mechanical properties and stability to water, attributing to the largest surface area and highest cellulose content of cotton stalk fibers by SFE-AT. SFE could separate bark of cotton stalks with high efficiency and subsequent mild AT could sufficiently remove the non-cellulose impurities by using NaOH solution with concentration as low as 5 g/L. Ultra-lightweight PP composites with the bulk density of 0.27 g/cm 3 could be prepared with cotton stalk fibers by SFE-AT. Overall, the method of SFE-AT with high efficiency and low cost could be very useful in exploring industrial applications of bark of cotton stalks and other lignocellulosic byproducts. [ABSTRACT FROM AUTHOR]

Specific and accurate determination of N1-Methyladenosine (m1A) is of critical significance to better understand its biological functions. Precise quantification of low level of RNA modification against a high background of homologous normal RNA still remains a big challenge. To solve this issue, a facile site-specific cleavage-assisted isothermal exponential amplification reaction (SSC-EXPAR) is skillfully designed for direct m1A assay. By exploiting the highly selective RNA cleavage, the normal RNA can be disconnected to avoid the false-positive interference, while the intact m1A can mediate and trigger three-way junction structure-based EXPAR (3WJ-EXPAR). The elegant design of m1A-aroused positive signal can guarantee the accurate and reliable detection of low-level m1A. As low as 1 fM of m1A-containing RNA can be accurately determined with a specificity allowing the discrimination of 0.5% m1A against unmodified adenosine (A) at single-base resolution. In virtue of the outstanding sensitivity and specificity, the SSC-EXPAR approach holds great potential in further understanding of m1A-associated biofunctions and the clinical value in diagnosis and therapeutic treatment of human cancers. • A facile site-specific RNA cleavage-assisted EXPAR strategy is devised for the detection of m1A. • Direct quantification of m1A is accomplished by the turn-on type positive signal generated by m1A. • The specificity is up to 0.5% to discriminate m1A against unmodified adenosine (A). • A strategy avoids the false-positive interference from abundance homologous normal RNA and can guarantee the accurate and reliable detection of low-level m1A. [ABSTRACT FROM AUTHOR]

To study mechanical behaviors of advanced carbon fiber reinforced composite (CFRC) sandwich cylinder with lattice cores, uni-axial compression and free vibration experiments were carried out. Load carrying capacity and local failure modes of the lattice-core sandwich cylinder (LSC) were revealed. Natural frequencies and vibration modes of CFRC LSC were revealed by experiments for the first time. For usual LSC in astronautic engineering, the first order vibration is in the plane of the cross section, turning from a circle to an oval. An equivalent method was proposed to predict the primary frequency and mode shape of the LSC, which is in excellent accordance with the experiment. Compared with grid stiffened cylinder (GSC), LSC of the same weight and dimension always has higher primary frequency, indicating that LSC is much stiffer and could be designed even lighter in astronautic applications. [ABSTRACT FROM AUTHOR]

The influence of biochar amendments on the physical quality of a clayey soil (Vertisol) was evaluated by aggregate-size distribution and stability, water retention, and pore-space structure of biochar-amended soils. Clayey soil was treated with three kinds of biochars (straw biochar, woodchips biochar, and wastewater-sludge biochar) at the rate of 0, 20, 40, and 60 g biochar (kg soil)-1 and incubated for 180 d in glasshouse. The application of straw biochar (SB) and wastewater-sludge biochar (WSB) significantly enhanced the formation of 5-2 and 0.25-0.5 mm macroaggregates in the clayey soil relative to the control treatment, while the < 0.25-cm microaggregate decreased with biochar additions. However, woodchips biochar (WCB) had no obvious effect on the formation of macroaggregate. The application of SB and WSB increased the mean weight diameter (MWD) and geometric mean diameter (GMD) of clayey soil, implying that biochar increased the aggregate stability. They improved the aggregate stability through an enhanced resistance to slaking and increased interparticular cohesion. The SB-amended soils exhibited significant increases in the available water contents of soils. The application of SB significantly increased pore volume in the macropore (> 75 μm) and mesopore (30-75 μm) ranges, which may be the result of the reorganization of pore-size distribution and aggregation processes induced by the addition of biochar. Results indicated that biochar had the potential to improve the physical quality and pore-space status of clayey soil. It is suggested that biochar may be considered as a soil amendment for improving poor physical characteristics of clayey soil. [ABSTRACT FROM AUTHOR]

Highlights: [•] A new hierarchical lattice truss composite with sandwich walls was designed and manufactured. [•] Strength and deformation characteristics of the hierarchical composites were revealed by tests. [•] Qualitative model was proposed to describe the deformation plateau of the composites. [•] Excellent mass efficiency and specific energy absorption of the composites were revealed. [ABSTRACT FROM AUTHOR]

Abstract: Sandwich cylindrical shells are the major components of aerospace structures. In this paper, an analytical investigation was carried out to examine the response of carbon fiber reinforced composite (CFRC) sandwich cylinders with lattice cores. An equivalent monocoque shell theory, was developed in this paper to predict mechanical behaviors of the quasi-isotropic sandwich cylinder, including the deformation and the multi-mode failure criterion. Five failure modes were suggested for the sandwich cylinder, including global buckling, face sheet mono-cell buckling/dimpling, face sheet local buckling, lattice rib crippling and strength failure. Using the suggested criterion, failure mode maps of the sandwich cylinder were acquired to instruct the design of the hierarchical sandwich cylinder with five geometrical variables. The method also correctly predicted the failure modes of the tested sandwich cylinder within acceptable errors. [Copyright &y& Elsevier]

This article describes the fabrication of a flexible polymer thin film incorporating a highly aligned Ag nanowire array, resulting in high transparency and polarisation that are useful for potential applications to optical filters, electronic and optical devices and negative refractive index materials. [ABSTRACT FROM PUBLISHER]

Abstract: A synthetic enzymatic pathway was designed for the deep oxidation of glucose in enzymatic fuel cells (EFCs). Polyphosphate glucokinase converts glucose to glucose-6-phosphate using low-cost, stable polyphosphate rather than costly ATP. Two NAD-dependent dehydrogenases (glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase) that were immobilized on the bioanode were responsible for generating two NADH per glucose-6-phosphate (i.e., four electrons were generated per glucose via a diaphorase-vitamin K3 electron shuttle system at the anode). Additionally, to prolong the enzyme lifetime and increase the power output, all of the recombinant enzymes that originated from thermophiles were expressed in Escherichia coli and purified to homogeneity. The maximum power density of the EFC with two dehydrogenases was 0.0203mWcm−2 in 10mM glucose at room temperature, which was 32% higher than that of an EFC with one dehydrogenase, suggesting that the deep oxidation of glucose had occurred. When the temperature was increased to 50°C, the maximum power density increased to 0.322mWcm−2, which was approximately eight times higher than that based on mesophilic enzymes at the same temperature. Our results suggest that the deep oxidation of glucose could be achieved by using multiple dehydrogenases in synthetic cascade pathways and that high power output could be achieved by using thermostable enzymes at elevated temperatures. [Copyright &y& Elsevier]

Abstract: The open reading frame TM1080 from Thermotoga maritima encoding ribose-5-phosphate isomerase type B (RpiB) was cloned and over-expressed in Escherichia coli BL21 (DE3). After optimization of cell culture conditions, more than 30% of intracellular proteins were soluble recombinant RpiB. High-purity RpiB was obtained by heat pretreatment through its optimization in buffer choice, buffer pH, as well as temperature and duration of pretreatment. This enzyme had the maximum activity at 70°C and pH 6.5–8.0. Under its suboptimal conditions (60°C and pH 7.0), k cat and K m values were 540s−1 and 7.6mM, respectively; it had a half lifetime of 71h, resulting in its turn-over number of more than 2×108 mol of product per mol of enzyme. This study suggests that it is highly feasible to discover thermostable enzymes from exploding genomic DNA database of extremophiles with the desired stability suitable for in vitro synthetic biology projects and produce high-purity thermoenzymes at very low costs. [Copyright &y& Elsevier]

Abstract: A multi-performance MWCNT-reinforced chitosan nanocomposite was fabricated by two methods: a freeze-drying process associated with the sublimation and compression (SAC) method; and the casting-evaporation (CE) method. We obtained ordered and multilayered structures with limited porosity, and well-dispersed MWCNT structures of the chitosan nanocomposite, especially with the SAC method. In the case of the nanocomposite films prepared by the CE method, the mechanical strength and elongation were significantly increased by up to about 40% compared with the pure chitosan films. On the other hand, the ordered and porous multilayered pure chitosan films prepared by the SAC method showed significantly lower tensile strength and elongation compared to the pure solid chitosan films. However, the relative enhancement of the mechanical properties of multilayered MWCNT/chitosan nanocomposites with porosity was higher, especially in terms of the elongation, which showed a twofold improvement in strain. The relaxed bond, which could be a relatively strong hydrogen bond, between the functional groups in the chitosan chains and the functionalized surface of the MWCNTs might be stretched under stress, thereby improving the ductility of the multilayered nanocomposite films. In addition, the viscoplastic behavior of the films by the CE method could become more active with increasing strain rate. Interestingly, ordered and porous pure chitosan films did not reveal the viscoplastic behavior; it rather presented strain softening and viscoelastic characteristics. However, the interaction between the chitosan chains and the surface-modified MWCNTs could regenerate viscoplasticity of the chitosan films. [Copyright &y& Elsevier]

Abstract: To overcome the poor mechanical properties of pure Cu thin films, we performed electrocodeposition to make nanocomposite thin films by incorporating inert Al2O3 nanoparticles (50nm and 300nm in diameter). In addition, to reduce agglomeration due to their high surface energy, we used ultrasonication during the electrocodeposition. In this paper, we examined the effects of the ultrasonication on the mechanical properties of nanocomposite films with different ultrasonic energy density up to 225W/cm2. Ultrasonication during electrocodeposition efficiently reduced the agglomeration of nanoparticles and reduced the grain size of the Cu matrix. Smaller nanoparticles were more efficiently de-agglomerated by ultrasonication, which resulted in more enhanced mechanical properties in the 50nm Al2O3 nanoparticle-enhanced specimens. Although the addition of nanoparticles in the Cu matrices significantly increased the hardness of the specimens, as observed in nanoindentation tests, we did not observe such an increase in tensile tests. Reducing the grain size by ultrasonication seems to be an important parameter in enhancing the overall mechanical properties of nanocomposites. Ultrasonication provided a significant increase in all mechanical properties, including elastic modulus, yield stress, ultimate tensile stress, and elongation, of all controlled Cu films. [ABSTRACT FROM AUTHOR]

Abstract: We present flexible nacre-like multi-layered films of chitosan and hydroxyapatite using manipulation of inherited polymeric phase separation in the solidification process. Films were characterized as homogeneous dispersity, high mechanical strength, and ordered microstructure in given optimized conditions of temperature and composite ratio. It resulted that the initial solidification temperature and the composition ratio are important factors in determination of homogeneity and mechanical strength of organic/inorganic composites. These films might be suitable for further osteological applications with surgical appliances, wound dressings, and space-filling implants. [Copyright &y& Elsevier]

We present two numerical methods for the approximation of the generalized Zakharov system (ZS). The first one is the time-splitting spectral (TSSP) method, which is explicit, time reversible, and time transverse invariant if the generalized ZS is, keeps the same decay rate of the wave energy as that in the generalized ZS, gives exact results for the plane-wave solution, and is of spectral-order accuracy in space and second-order accuracy in time. The second one is to use a local spectral method, the discrete singular convolution (DSC) for spatial derivatives and the fourth-order Runge–Kutta (RK4) for time integration, which is of high (the same as spectral)-order accuracy in space and can be applied to deal with general boundary conditions. In order to test accuracy and stability, we compare these two methods with other existing methods: Fourier pseudospectral method (FPS) and wavelet-Galerkin method (WG) for spatial derivatives combining with the RK4 for time integration, as well as the standard finite difference method (FD) for solving the ZS with a solitary-wave solution. Furthermore, extensive numerical tests are presented for plane waves, solitary-wave collisions in 1d, as well as a 2d problem of the generalized ZS. Numerical results show that TSSP and DSC are spectral-order accuracy in space and much more accurate than FD, and for stability, TSSP requires k=O(h), DSC–RK4 requires k=O(h2) for fixed acoustic speed, where k is the time step and h is the spatial mesh size. [Copyright &y& Elsevier]