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In this study, a piezoelectric nanogenerator (PENG) based on multilayer composite fiber had good and stable piezoelectric output performance, which could realize biomechanical energy collection and human movement monitoring. The polyvinylidene fluoride‐hexafluoryl propylene (P(VDF‐HFP)) composite fiber doped with MXene was used as a promising piezoelectric functional layer (MPFP). By electrospinning, P(VDF‐HFP) composite fiber was constructed by alternating electrospinning with polyurethane (TPU) nanofibers layer by layer. The adoption of MXene as a functional filler promoted the transformation of P(VDF‐HFP) from α to piezoelectric β‐crystal, the piezoelectric β‐crystal content of P(VDF‐HFP) increased, and the dielectric properties and polarization levels were enhanced. At the same time, the multi‐layer structure design improved the piezoelectric sensitivity and mechanical properties of the composite fiber, and the composite fiber was more flexible and had longer tensile strain. With excellent dielectric and mechanical properties, 3MPFP/TPU/3MPFP/TPU multilayer composite fibers showed piezoelectric sensitivity of 10.88 V/kPa. Under the action of palm pressing, the PENG generated an open circuit voltage of 25 V, and the voltage signal of the device under different motion forms had specific characteristics such as peak value, frequency, and shape, which could be used to realize the analysis of human motion forms. This study provided an efficient, simple, and creative new idea for the application of flexible energy storage electronic devices, PENGs, and piezoelectric sensors. [ABSTRACT FROM AUTHOR]

Structural materials such as ceramics, metals, and carbon fiber‐reinforced plastics (CFRP) are frequently threatened by large compressive and impact forces. Energy absorption layers, i.e., polyurethane and silicone foams with excellent damping properties, are applied on the surfaces of different substrates to absorb energy. However, the amount of energy dissipation and penetration resistance are limited in commercial polyurethane foams. Herein, a distinctive nacre‐like architecture design strategy is proposed by integrating hard porous ceramic frameworks and flexible polyurethane buffers to improve energy absorption and impact resistance. Experimental investigations reveal the bioinspired designs exhibit optimized hardness, strength, and modulus compared to that of polyurethane. Due to the multiscale energy dissipation mechanisms, the resulting normalized absorbed energy (≈8.557 MJ m−3) is ≈20 times higher than polyurethane foams under 50% quasi‐static compression. The bioinspired composites provide superior protection for structural materials (CFRP, glass, and steel), surpassing polyurethane films under impact loadings. It is shown CFRP coated with the designed materials can withstand more than ten impact loadings (in energy of 10 J) without obvious damage, which otherwise delaminates after a single impact. This biomimetic design strategy holds the potential to offer valuable insights for the development of lightweight, energy‐absorbent, and impact‐resistant materials. [ABSTRACT FROM AUTHOR]

Poly(styrene‐b‐isobutylene‐b‐styrene) (SIBS) is a biomedical elastomer with excellent overall properties. However, the low surface energy and the surface hydrophobicity of SIBS have limited its application as a human implantable material. To improve its biocompatibility, in this work, hyaluronic acid (HA) was introduced onto the surface of SIBS. Firstly, glycidyl methacrylate (GMA) and HA were employed to prepare GMA‐modified HA (GMHA) via grafting reaction. Due to the introduction of carbon–carbon double bonds on the side chain of HA, the GMHA could be used for free radical polymerization between SIBS. The effects of UV illumination time, GMHA concentration, and initiator concentration on the grafting ratio were investigated. FTIR, 1H NMR, and XPS confirmed the successful grafting of HA onto SIBS. The experimental results showed that the surface modification method not only ensured that the excellent properties of the SIBS would not be destroyed but also improved its surface properties successfully. Besides, the MTT assay indicated that the GMHA‐modified SIBS was not bio‐toxic, so it could meet the need to expand its use in the biomedical fields. [ABSTRACT FROM AUTHOR]

Temporal control of chain growth is a central challenge for photoinitiated active polymerization. In this work, we introduced an iridium salt complex‐based catalyst system to achieve fine temporal control of the chain growth process. By electrochemical analysis, compared with the pyran salt photocatalyst, it was found that the iridium salt complex could promote the chain transfer of active species to reversible addition‐fragmentation chain transfer polymerization (RAFT) reagent, thereby generating dormant species, which provided the possibility of time control of the polymerization process. Using this catalytic system, we successfully achieved homopolymerization of vinyl ethers with different substituents and random copolymerization with isobutyl vinyl ethers, which is not only pointed the way for broadening the monomer selection in the future, but also provided an innovative way to prepare new functionalized materials. [ABSTRACT FROM AUTHOR]

De novo anti‐HLA donor‐specific antibodies (DSAs) were rarely reported in stem cell transplantation patients. We present a case of 39‐year‐old acute myelogenous leukaemia patient who developed de novo DSAs only 16 days after transplantation with the highest mean fluorescence intensity (MFI) of 7406.23, which were associated with poor graft function (PGF). We used plasma exchange (PE) and intravenous immunoglobulin (IVIg) to reduce DSA level. A series of treatment including mesenchymal stem cells and donor cell transfusion were used to help recover graft function. On day 130, the patient achieved a successful engraftment. [ABSTRACT FROM AUTHOR]

Traditional living/controlled cationic polymerization provides a simple synthetic route for the preparation of various polymers with set molecular weight, narrow molecular weight distribution, and clear structure. Nowadays, under the requirements of sustainable development, it is very important to explore the green chemical technology in depth. This review offers an overview of initiation systems, reaction media, polymerization techniques, and monomers, with the aim of summarizing environmentally friendly methods utilized in the field of cationic polymerization over the past 15 years. It covers a variety of directions from traditional initiation systems to green initiators, from corrosive solvents to environmentally friendly solvents, from drop initiation to external stimulation initiation, from petroleum fractionated monomers to bio‐based monomers. These methods and Techniques aim to develop advanced high‐quality polymer products using cationic polymerization, and achieving efficient energy savings and reducing emissions. The ongoing exploration of green‐controlled cationic polymerization holds promise for opening up new avenues and novel technology for high‐performance polyolefin materials. [ABSTRACT FROM AUTHOR]

ChinaMu is the largest sequence‐indexed Mutator (Mu) transposon insertional library in maize (Zea mays). In this study, we made significant improvements to the size and quality of the ChinaMu library. We developed a new Mu‐tag isolation method Mu‐Tn5‐seq (MuT‐seq). Compared to the previous method used by ChinaMu, MuT‐seq recovered 1/3 more germinal insertions, while requiring only about 1/14 of the sequencing volume and 1/5 of the experimental time. Using MuT‐seq, we identified 113,879 germinal insertions from 3,168 Mu‐active F1 families. We also assembled a high‐quality genome for the Mu‐active line Mu‐starter, which harbors the initial active MuDR element and was used as the pollen donor for the mutation population. Using the Mu‐starter genome, we recovered 33,662 (15.6%) additional germinal insertions in 3,244 (7.4%) genes in the Mu‐starter line. The Mu‐starter genome also improved the assignment of 117,689 (54.5%) germinal insertions. The newly upgraded ChinaMu dataset currently contains 215,889 high‐quality germinal insertions. These insertions cover 32,224 pan‐genes in the Mu‐starter and B73Ref5 genomes, including 23,006 (80.4%) core genes shared by the two genomes. As a test model, we investigated Mu insertions in the pentatricopeptide repeat (PPR) superfamily, discovering insertions for 92% (449/487) of PPR genes in ChinaMu, demonstrating the usefulness of ChinaMu as a functional genomics resource for maize. [ABSTRACT FROM AUTHOR]

Flexible piezoelectric sensors combine advantages including low‐cost, flexibility, multi‐functions, present a huge market prospect. In this research, multiwalled carbon nanotubes (MWCNT)/MXene/polyacrylonitrile (PAN) piezoelectric composites films for flexible piezoelectric sensors are fabricated by electrospinning technology, the planar zigzag conformation content of 97.98% in PAN composite fibers is achieved owing to the synergistic effect of MWCNT and MXene, the synergistic effect of MWCNT and MXene nanoparticles can also efficiently promote the mechanical performance and piezoelectric output. The piezoelectric sensor exhibits fast response time (10.21 ms), a possible mechanism is proposed to explain the improvement of piezoelectric effect. The sensor can measure human pulse, distinguish human movements, the fabricated sensor has broad practical value in the field of healthcare, its' use can contribute to stable and accurate measurements of physiological parameters, enabling applications in various healthcare and fitness monitoring scenarios. [ABSTRACT FROM AUTHOR]

Background: Health‐related quality of life (HRQOL) is unequal between countries and regions, and the emphasis on HRQOL of populations of low‐income countries and regions is unprecedented. Objectives: To examine the association between family health and HRQOL among middle‐aged and older adults in rural China, and determine whether this association differs by age, gender and chronic disease subgroup. Methods: Cross‐sectional survey carried out from July to September 2021. The participants were 1059 people aged 46 and over living in rural China. We used the European Quality of Life Five Dimension Five Level (EQ‐5D‐5L) and Family Health Scale‐Short Form (FHS‐SF) to assess health‐related quality of life (HRQOL) and family health, respectively. Results: The mean EQ‐VAS was 75.66, the mean EQ index score was 0.92, and the mean FHS was 37.90 in rural middle‐aged and older adults. After Bonferroni correction, generalised linear regression models showed that FHS was significantly associated with the EQ‐VAS (β = 0.829; 95% confidence interval [CI]: 0.660 to 0.997; p <.001) and the EQ index score (β = 0.003; 95%CI: 0.001 to 0.004; p <.001). Binary logistic regression models showed that FHS was associated with three dimensions of HRQOL (mobility, self‐care and usual activities) (p <.01). Based on subgroup analyses, the effect of FHS on EQ‐VAS and the EQ index score was significant in three subgroups after Bonferroni correction (p <.01), but the association between FHS and the dimensions of HRQOL differed by age, gender and chronic disease group (p >.01). Conclusions: This study is the first to explore that family health and its dimensions are significant positive predictors of HRQOL among middle‐aged and older adults in rural China. Family‐based measures may have more potential and value because better family health significantly improves HRQOL. Implications for practice: In the health strategy, the government and primary health care workers should include family health as an indicator and assess it before and after the implementation of the strategy. [ABSTRACT FROM AUTHOR]

Background: The infiltrative nature of human gliomas renders complete surgical removal of tumors futile. Thus, illuminating mechanisms of their infiltrative properties may improve therapies and outcomes of glioma patients. Methods: Comprehensive bioinformatic analyses of PRSS family were undertaken. Transfection of HTRA1 siRNAs was used to suppress HTRA1 expression. CCK‐8, EdU, and colony formation assay were employed to assess cell viability, and cell migration/invasion was detected by transwell, wound healing, and 3D tumor spheroid invasion assays. Immunoprecipitation was applied to study the mechanism that HTRA1 affected cell migration. In addition, in situ xenograft tumor model was employed to explore the role of HTRA1 in glioma growth in vivo. Results: HTRA1 knockdown could lead to suppression of cell viability, migration and invasion, as well as increased apoptosis. Immunoprecipitation results indicates HTRA1 might facilitate combination between HDAC6 and α‐tubulin to enhance cell migration by decreasing α‐tubulin acetylation. Besides, HTRA1 knockdown inhibited the growth of xenografts derived from orthotopic implantation of GBM cells and prolonged the survival time of tumor‐bearing mice. Conclusion: Our results indicate that HTRA1 promotes the proliferation and migration of GBM cells in vitro and in vivo, and thus may be a potential target for treatment in gliomas. [ABSTRACT FROM AUTHOR]

Objective: This study investigated the cellular composition of peripheral blood grafts for anti‐thymocyte globulin (ATG)‐based myeloablative haploidentical haematopoietic stem cell transplantation (haplo‐HSCT). Methods: Clinical characteristics were retrospectively evaluated in a training cohort with ATG‐based myeloablative haplo‐HSCT between January 2016 and February 2020 and confirmed in a validation cohort between March 2020 and June 2021. Results: A higher dose of graft CD8+ T cells (≥ 0.85 × 108 kg−1) was significantly improved overall survival (OS; hazard ratio [HR], 1.750; P = 0.002) and disease‐free survival (DFS; HR, 1.751; P < 0.001) in the training cohort, according to multivariate Cox regression analysis. Higher doses of mononuclear cells (MNCs) demonstrated better OS (HR, 1.517; P = 0.038) and DFS (HR, 1.532; P = 0.027). Older patient age (> 46 years), older donor age (≥ 50 years) and a higher refined disease risk index (rDRI) were also related to OS. A graft CD8+ T‐cell risk system based on graft CD8+ T‐cell dose, donor age and rDRI was constructed using a nomogram model after LASSO Cox regression analysis. It showed acceptable discrimination, with a C‐index of 0.62 and 0.63, respectively. Graft CD8+ T‐cell dose was negatively correlated with donor age (P < 0.001) and positively correlated with a higher lymphocyte percentage in the peripheral blood before mobilisation (P < 0.001). Conclusion: A higher CD8+ T‐cell dose in peripheral blood‐derived grafts improves patients' survival with ATG‐based myeloablative haplo‐HSCT. Younger donors with higher lymphocyte percentages improved patients' survival with an intermediate rDRI risk. [ABSTRACT FROM AUTHOR]

Summary: Donor‐specific anti‐HLA antibodies (DSA) are a major cause of engraftment failure in patients receiving haploidentical haematopoietic stem cell transplantation (Haplo‐HSCT). Double filtration plasmapheresis (DFPP) avoids the unnecessary loss of plasma proteins and increases the efficiency of purification. To investigate the effectiveness of the desensitization protocol including DFPP and rituximab, we conducted a nested case–control study. Thirty‐three patients who had positive DSA were desensitized by the protocol and 99 patients with negative DSA were randomly matched as control. The median DSA mean fluorescence intensity values before and after DFPP treatment were 7505.88 ± 4424.38 versus 2013.29 ± 4067.22 (p < 0.001). All patients in DSA group achieved haematopoietic reconstitution and the median neutrophils and platelets engraftment times were 13 (10–21) and 13 (10–29) days respectively. Although the cumulative incidence of II–IV aGVHD (41.4% vs. 28.1%) and 3‐year moderate to severe cGVHD (16.8% vs. 7.2%) were higher in DSA cohort than in the control, no statistical significance was observed. The 3‐year non‐relapse mortality and the overall survival were 6.39% and 72.0%, respectively, in the DSA cohort, which were comparable to the negative control. In conclusion, DFPP and rituximab could be effectively used for desensitization and overcome the negative effects of DSA in Haplo‐HSCT. [ABSTRACT FROM AUTHOR]

Cationic polymerization is an important branch of polymer chemistry. Traditional cationic polymerization must be carried out in anhydrous and low temperature environment, with harsh operating conditions, high operating costs and high energy consumption. Visible light induced cationic polymerization is simple, environmentally friendly, and low‐cost, so it has become a research hotspot of living cationic polymerization. This paper gives an overview of the recent advances (mainly from 2015 to 2023) on visible‐light‐induced cationic polymerization, with a focus on visible‐light‐initiated and visible‐light‐controlled cationic polymerization. On the basis of controlling cationic polymerization to achieve macromolecular reaction engineering, the realization of temporal scale control will be the main development direction in the future. [ABSTRACT FROM AUTHOR]

Summary: Most events that limit life expectancy after allogeneic haematopoietic stem cell transplantation (allo‐HSCT) occur within the first 2 years; however, treatment outcomes in long‐term survivors who survive for at least 2 years post‐HSCT without relapse are yet to be elucidated. To explore the life expectancy trends and late complications and to assess the main mortality‐related factors, we investigated the characteristics of patients who received allo‐HSCT for haematological malignancies from 2007 to 2019 in our centre and survived in remission for 2 years. A cohort of 831 patients was enrolled; of these, 508 received grafts from haploidentical‐related donors (61.1%). The estimated overall survival rate at 10 years was 91.9% (95% confidence interval [CI], 89.8–93.5), which was affected by prior grade III–IV acute graft‐versus‐host disease (GVHD) (hazard ratio [HR], 2.98; 95% CI, 1.47–6.03; p = 0.002) and severe chronic GVHD (HR, 3.60; 95% CI, 1.93–6.71; p < 0.001). The probability of late relapse and non‐relapse mortality at 10 years was 8.7% (95% CI, 6.9–10.8) and 3.6% (95% CI, 2.5–5.1) respectively. The top cause of late mortality was relapsed (49.0%). Projected long‐term survival in 2‐year disease‐free survivors following allo‐HSCT was excellent. Strategies should be implemented to minimise the late death‐specific hazards in recipients. [ABSTRACT FROM AUTHOR]

The cationic polymerization of isobutene vinyl ether(IBVE) contains waters system was achieved by using triphenylmethylium tetrakis‐(pentafluorophenyl)borate [Ph3C][B(C6F5)4], which overcame the harsh experimental requirements of traditional cationic polymerization. The influences of water content, solvent polarity, and reaction temperature on polymerization were studied. The end structure of the polymer was analyzed by 1H‐NMR. Combined with the effect of the proton trapping agent and triethylamine salt which can trap [H+], it was found that there was a reversible equilibrium between [Ph3C+] and [H+] active species during the polymerization process. The cationic polymerizations of isobutyl vinyl ether were initiated by these two active species simultaneously. The controllable cationic polymerization of isobutyl vinyl ether was achieved by the addition of ethyl methyl carbonate and ethyl benzoate. Gaussian 09 W simulation confirms the polymerization mechanism. [ABSTRACT FROM AUTHOR]

On the basis of synthesizing a highly efficient chain‐transfer agent ethyl (1‐isobutoxyethyl) carbonotrithioate(CTA), living cationic polymerization of isobutyl vinyl ether (IBVE) was successfully initiated by visible light catalysis. The random copolymerization of isobutyl vinyl ether and propyl vinyl ether (PVE), cyclohexyl vinyl ether (CyVE), and 2‐chloroethyl vinyl ether (CEVE) was achieved on the basis of investigating the reactivity ratios of vinyl ether monomers. The influence of photocatalyst (PC) concentration and wavelength on the copolymerizations was investigated. It was found that high PC concentration results in a fast polymerization rate. The wavelength of the blue LED was most suitable for this reaction system. This photocatalytic reaction provides a new way for molecular design of cationic polymerization. [ABSTRACT FROM AUTHOR]

Here, we demonstrate the design and application of a multifunctional piezoelectric composite nanofiber membrane. In this study, the most widely used electrospinning method, by adding a small amount of 1‐allyl‐3‐butylimidazolium tetrafluoroborate ionic liquids and ferric chloride hexahydrate (FeCl3·6H2O) to regulate the structure and properties of polyacrylonitrile (PAN), the mechanical properties, piezoelectric properties, dielectric properties, and ferroelectric properties of composite nanofibers were improved. The results show that the piezoelectric properties of PAN composite fibers are greatly improved under the action of dual fillers. At 103 Hz, the dielectric constant of the PAN composite fiber is as high as 8.24, which is three times that of the pure PAN fiber. The sensor made from the composite nanofibers exhibits excellent sensitivity and high saturation polarization. At low pressure (<1 kPa), the sensitivity of the composite fiber is as high as 0.51 kPa. When we tap the sensor with our finger, the PAN composite fiber produces high piezoelectric output (5.7 V). The results show that the composite nanofibers have great potential in energy storage devices and flexible piezoelectric sensors, among other fields. [ABSTRACT FROM AUTHOR]

In this paper, barium titanate nanoparticles (BaTiO3, BT) were incorporated into the polyurethane (TPU) matrix to prepare dielectric elastomer composites. Then, the composites were thermal treated to improve the interfacial compatibility between TPU and BT, enhance the interface polarization, and improve the dielectric properties. The results showed that the dielectric constant of the composites after thermal treatment at 150°C reached to 7.3 at 1 kHz, the elongation at break remained 1934%, and the elastic modulus (Y) dropped to 4.4 MPa. In addition, the discharge energy density reached 73 mJ/cm3 under an electric field of 300 kV/cm, and charge–discharge energy conversion efficiency was up to 84%. More importantly, the electrically actuated displacement of 2.61 mm at electric field of 160 kV/cm was 1.7 times greater than that of untreated composites. The composites worked stably under the action of the circulating electric field. This study provided a new strategy for obtaining high‐performance dielectric elastomer actuators, which were expected to be applied to biomimetic robots, human skin, or dielectric energy storage devices. [ABSTRACT FROM AUTHOR]

D‐A conjugated polymers P1 and P2 are synthesized by copolymerizing bisthiophene‐fused diketopyrrolopyrrole (4,11‐bis(2‐decyltetradecyl)‐7H,14H‐thieno[3',2':7,8]‐indolizino[2,1‐a]thieno[3,2‐g]indolizine‐7,14‐dione, BTI) with terthiophene and thiophene‐benzothiadiazole‐thiophene, respectively. Molecular packing is characterized by X‐ray diffraction. The film morphology is characterized by atomic force and scanning electron microscopy. The vertical phase separation is characterized by XPS. The mechanism of film morphology formation is explained from intermolecular interaction, kinetics, and surface free energy. The spin‐coated films of polymers blended with PC71BM are served as semiconductor layers in near‐infrared (NIR) phototransistors. The impact of morphology on optoelectronic performance is analyzed. The mobility of organic field effect transistors based on P1 or P2 thin films remains constant with the addition of PC71BM with weight ratio being less than 50%. The main reason is that π–π stacking in both P1 and P2 thin films is at all directions and PC71BM does not disturb the charge percolation path. Benzothiadiazole in P2 enables stronger mutual attraction between P2 and PC71BM, and therefore large contact area between P2 and PC71BM forms in the heterojunction. The photoresponsivity improves by 2 times for NIR phototransistors based on P2/PC71BM when decreasing light intensity from 63 to 1.8 µW cm‐2. The above results suggest a feasible conjugated polymer design rule for high sensitivity NIR phototransistors. [ABSTRACT FROM AUTHOR]

This study reported the self‐healing behavior of natural rubber (NR) and NR‐butyl rubber (IIR) composites, which was enhanced by graft‐polymerization of zinc dimethacrylate (ZDMA) onto rubber chains. Using dicumyl peroxide (DCP) as the vulcanization agent formed a reversible covalent/ionic crosslinking supermolecular network. By controlling the vulcanization process, a reversible supramolecular network composed of covalent cross‐linking, ionic cross‐linking, and physical entanglement is obtained. Experiments shown that the self‐repairing behavior of ionic bonds comes from the recombination of ionic clusters. Although the saturated backbone of IIR is hardly to provide ionic or covalent crosslinks, the addition of IIR can increase the degree of physical entanglements level of rubber and provide physical self‐healing behavior. The entanglement healing is weaker than ionic cross‐linking, but due to the better chain mobility, the multiple times healing ability of IIR introduced by entanglements is better than covalent or ionic bonds. [ABSTRACT FROM AUTHOR]

Summary: One of the most complex issues with haploidentical stem cell transplantation (haplo‐SCT) is donor selection, given that multiple haploidentical donors are often available for a given recipient. To develop evidence‐based guidance for donor selection in the setting of anti‐thymocyte globulin‐based haplo‐SCT, we performed a prospective cohort study of 512 patients with haematological malignancies who had haplo‐SCT to determine which donor variables were most important in favouring transplant outcomes. Increasing donor age was associated with poorer overall survival (OS) [hazard ratio (HR) 1·08, P = 0·044]. Female donors to male recipients was significantly associated with higher non‐relapse mortality (NRM; HR 2·05, P = 0·006). Furthermore, increasing donor age had a higher risk of Grades 3–4 acute graft‐versus‐host disease (aGVHD; HR 1·17, P = 0·005), female donors to male recipients was associated with a higher risk of Grades 2–4 aGVHD (HR 1·50, P = 0·022). Sibling donors had superior OS, disease‐free survival, and NRM than parental donors in patients aged <35 years. However, sibling donors had higher NRM than offspring donors in patients aged ≥35 years. A younger donor, usually a young sibling in younger recipients (aged <35 years) or a young offspring in older patients (aged ≥35 years) and avoiding female donors to male recipients should be preferred when multiple haploidentical donors are available. [ABSTRACT FROM AUTHOR]

Exploring sustainable, low‐cost and high‐performance non‐noble metal (NNM) electrocatalysts as alternatives to Pt‐based catalysts for oxygen reduction reaction (ORR) is crucial for the large‐scale application of metal‐air batteries and fuel cell technology. A new method for preparing ORR catalysts is to use biomass activated carbon supported transition metal. Biomass activated carbon has a highly porous structure which is beneficial to charge and energy transport. In this article, peanut shell activated carbon (PSAC) was prepared as a carrier and iron phthalocyanine (FePc) was the active component of the catalyst. Different mass ratios of the FePc and PSAC were selected for physical doping and then treated at a high temperature. The obtained catalyst FePc/PSAC‐3/1 showed excellent ORR catalytic performance, the onset potential and the half‐wave potential are 0.94 V and 0.85 V respectively, highly comparable to that of commercial Pt/C (20 wt% Pt) catalyst. FePc/PSAC‐3/1 has good stability and better tolerance to the methanol crossover effect than the Pt/C catalyst in alkaline electrolytes. The product was further used as an air cathode to construct the Zn‐air battery at the same time. The excellent recharge‐ability was further evaluated by a 43 h long‐term cycling test without noticeable deterioration for the voltage gap. This work demonstrates the great promise of developing new families of NNM ORR catalysts by the economical and sustainable process. [ABSTRACT FROM AUTHOR]

A series of tin‐organic frameworks materials (SnMOF) were synthesized using different organic linkers, including phthalic acid, isophthalic acid, 1,4‐dicarboxybenzene, and 1,3,5‐benzenetricarboxylic acid. The structure and morphology of SnMOF were characterized by Fourier Transform infrared spectroscopy (FT‐IR), X‐ray diffraction, N2 adsorption/desorption isortherm (BET), scanning electron microscope‐Energy Dispersive System (EDS), and Thermogravimetry (TG). Taking together, these experimental results indicated that the different types and amounts of COOH in organic linkers have a significant effect on the physical properties of SnMOF. Among them, carbon‐supported SnMOF as catalysts for acetylene hydrochlorination features the considerable activity and vinyl chloride selectivity. Such excellent performance is attributed to the fact that 1,3,5‐benzenetricarboxylic acid can effectively strengthen the interaction effect between C2H2 and Sn‐O‐C, according to the results of C2H2‐TPD, HCl adsorption experiments, and X‐ray photoelectron spectroscopy (XPS). [ABSTRACT FROM AUTHOR]

Objectives: Stem cell niche regulated the renewal and differentiation of germline stem cells (GSCs) in Drosophila. Previously, we and others identified a series of genes encoding ribosomal proteins that may contribute to the self‐renewal and differentiation of GSCs. However, the mechanisms that maintain and differentiate GSCs in their niches were not well understood. Materials and Methods: Flies were used to generate tissue‐specific gene knockdown. Small interfering RNAs were used to knockdown genes in S2 cells. qRT‐PCR was used to examine the relative mRNA expression level. TUNEL staining or flow cytometry assays were used to detect cell survival. Immunofluorescence was used to determine protein localization and expression pattern. Results: Herein, using a genetic manipulation approach, we investigated the role of ribosomal protein S13 (RpS13) in testes and S2 cells. We reported that RpS13 was required for the self‐renewal and differentiation of GSCs. We also demonstrated that RpS13 regulated cell proliferation and apoptosis. Mechanistically, we showed that RpS13 regulated the expression of ribosome subunits and could moderate the expression of the Rho1, DE‐cad and Arm proteins. Notably, Rho1 imitated the phenotype of RpS13 in both Drosophila testes and S2 cells, and recruited cell adhesions, which was mediated by the DE‐cad and Arm proteins. Conclusion: These findings uncover a novel mechanism of RpS13 that mediates Rho1 signals in the stem cell niche of the Drosophila testis. [ABSTRACT FROM AUTHOR]

In this study, metal organic framework/activated carbon catalysts (X–MOF/AC, where X=Sn or Cu) were synthesized using a facile method and used for the acetylene hydrochlorination reaction. The prepared catalysts were characterized using Fouriertransform infrared spectroscopy (FTIR), X‐ray diffraction analysis(XRD), nitrogen adsorption‐desorption analysis, thermo‐gravimetric analysis (TGA), acetylene temperature‐programmed desorption experiments (C2H2‐TPD), hydrogen temperature‐programmed reduction experiments (H2‐TPR), X‐ray photoelectron spectroscopy (XPS) and scanning electron microscopy‐energy dispersive spectroscopy (SEM‐EDS). Compared with Cu–MOF/AC, Sn‐MOF/AC behaved the highest acetylene conversion of 93.5% under the conditions of 200 °C and an acetylene gas space velocity of 30 h−1. Furthermore, XRD, TGA and SEM‐EDS results showed that Sn‐MOF and Cu–MOF possesse different morphology and thermalstability, respectively. Additionally, C2H2‐TPD and TGA results indicated that Sn‐MOF/AC displays the higher acetylene adsorption and the better anti‐coking ability as compare to Cu–MOF/AC. [ABSTRACT FROM AUTHOR]

We used a minirhizotron system to investigate the influence of three major factors-root morphology, root depth, and season of root emergence-on root survivorship and longevity in a Kobresia humilis meadow on the Tibetan Plateau during the growing season of 2009. Root longevity was assessed by survival analysis, Kaplan-Meier analysis, and Cox proportional hazards regression. Root longevity was correlated positively with root diameter. A 17.5 % decrease in the risk of mortality was associated with a 0.1-mm increase in diameter. Roots distributed in the top 10 cm of the soil had significantly shorter longevities than roots at greater depths, with a 48 % decrease of mortality risk for each 10-cm increase in soil depth from the surface to 40 cm. Of all the factors examined, the season of root emergence had the strongest effect on root lifespan. Roots that emerged in May and June had shorter longevity than roots that emerged later in the year, and roots that emerged in September and October were more likely to survive over winter. Our findings indicated that life-history traits of roots in K. humilis meadows are highly heterogeneous, and this heterogeneity should be considered when modeling the contribution of roots to carbon and nitrogen fluxes in this type of meadow ecosystem. Moreover, temporal, spatial, and compositional variations in root longevity must be considered. [ABSTRACT FROM AUTHOR]

The article focuses on the study on the synthesis of star-shaped polyisobutylene (PIB) with polystyrene-b-polyisoprene-b-polystyrene (SIpS) triblock copolymers. The study used the 2-Chloro-2,4,4-trimethylpentane (TMPCl)/ Titanium tetrachloride TiCl4/SIpS triblock copolymer/2,6-di-tert-butylpyridine (DtBP) initiating system cationic polymerization to accomplished PIB. Results show that the integration of SIpS triblock copolymers in the star-branched polymers are confirmed.

To improve the properties of diblock copolystyrene‐based anion exchange membranes (AEMs), a series of AEMs with comb‐shaped quaternary ammonium (QA) architecture (QA‐PSm‐b‐PDVPPAn‐xC where x denotes the number of carbon atoms in different alkyl tail chains and has values of 1, 4, 8, and 10 and C denotes carbon) were designed and synthesized via subsequent quaternization reactions with three different alkyl halogens (methyl iodide and N‐alkane bromines (CH3[CH2]x‐1Br where x = 4, 8, and 10). Compared with triblock analogues quaternized with methyl iodide in our previous research, QA‐PSm‐b‐PDVPPAn‐xC (x = 4, 8, and 10) AEMs are more flexible with the introduction of a long alkyl tail chain; this probably impedes crystallization of the rigid polystyrene‐based main chain and induces sterically adjustable ionic association. An increase in the pendant alkyl tail chain length generally led to enhanced microphase separation of the obtained AEMs, and this was confirmed using small‐angle X‐ray scattering and atomic force microscopy. The highest conductivity (25.5 mS cm−1) was observed for QA‐PS120‐b‐PDVPPA80‐10C (IEC = 1.94 meq g–1) at 20 °C. Furthermore, the water uptake (<30%) and swelling ratio (<13.1%) of QA‐PSm‐b‐PDVPPAn‐xC AEMs are less than half of these corresponding values for their triblock counterparts. The QA‐PS120‐b‐PDVPPA80‐10C membrane retained a maximum stability that was as high as 86.8% of its initial conductivity after a 40‐day test (10 M NaOH, 80 °C), and this was probably because of the steric shielding of the cationic domains that were surrounded by the longest alkyl tail chains. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47370. [ABSTRACT FROM AUTHOR]

Styrene cationic polymerizations initiated by cumyl alcohol (CumOH)/B(C6F5)3 are systematically studied in aqueous suspension and emulsion. Theoretical calculations and experimental research suggest that CumOH/B(C6F5)3 has higher initiating activity than H2O/B(C6F5)3. During emulsion polymerization of styrene, molecular weight and polymerization rate decrease with the addition of surfactants. These polymerization processes share the same features. Specifically, all elemental reactions (initiation, propagation, and termination) in aqueous media occur at the droplet interface. End structure analysis indicates that chain transfer reactions to water and a‐proton elimination and chain transfer reactions to monomer occur. The possible mechanism for the styrene cationic polymerization in aqueous media is demonstrated. Poly(styrene)s are successfully synthesized in aqueous media by using cumyl alcohol initiating system. All elemental reactions (initiation, propagation, and termination) in aqueous media occur at the droplet interface. Chain transfer reactions to water and β‐proton elimination and chain transfer reactions to monomer occur. The polymerization characteristics and corresponding polymerization mechanism are investigated. [ABSTRACT FROM AUTHOR]

Styrene cationic polymerizations initiated by cumyl alcohol (CumOH)/B(C6F5)3 are systematically studied in aqueous suspension and emulsion. Theoretical calculations and experimental research suggest that CumOH/B(C6F5)3 has higher initiating activity than H2O/B(C6F5)3. During emulsion polymerization of styrene, molecular weight and polymerization rate decrease with the addition of surfactants. These polymerization processes share the same features. Specifically, all elemental reactions (initiation, propagation, and termination) in aqueous media occur at the droplet interface. End structure analysis indicates that chain transfer reactions to water and a‐proton elimination and chain transfer reactions to monomer occur. The possible mechanism for the styrene cationic polymerization in aqueous media is demonstrated. Poly(styrene)s are successfully synthesized in aqueous media by using cumyl alcohol initiating system. All elemental reactions (initiation, propagation, and termination) in aqueous media occur at the droplet interface. Chain transfer reactions to water and β‐proton elimination and chain transfer reactions to monomer occur. The polymerization characteristics and corresponding polymerization mechanism are investigated. [ABSTRACT FROM AUTHOR]