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Iron-based hydroxyl oxides can be regarded as feasible electrodes for sodium-ion batteries due to the simple preparation and rich resources. Goethite nanorod clusters that are wrapped by multi-walled carbon nanotubes with an open tunnel structure exhibit a considerable capacity, a favourable durability and an excellent rate capability within loose working conditions. The structural and electrochemical stability of this anode can be maintained when exposed at ambient environment after 30 days. Moreover, this anode coupled with high-quality Prussian blue cathode delivers feasible energy density of 60 W h kg−1 calculated on the basis of the pouch cell. Abundant voids formed by Kirkendall effect in nanorods allow for the simultaneous promotion of electrolyte infiltration, ion transfer and the pseudocapacitive effect. According to a series of ex situ and in situ measurements, the intercalation and conversion reactions for sodium storage have been revealed and low-volume deformation was observed during the sodiated/desodiated process. In particular, the existence of Na x FeOOH, Fe, NaOH and Na 2 O species at fully discharged state indicates an incomplete conversion reaction, resulting in steerable volume expansion and high ionic/electrical conductivity. The advanced sodium storage kinetics can be attributed to the moderate diffusion barrier and remarkable pseudocapacitive effect. Innovatively, a low-strain and high-capacity anode was developed by building porous nanorods cluster and incomplete conversion reaction. After fully discharged, a volume expansion of only 35% can be intuitively observed by in-situ TEM images. Moreover, the outstanding rate performance has been achieved via the significant pseudocapacitive contribution and fast tunnel-type diffusion path for Na+ ions. Image 1 • Porous α-FeOOH nanorods and clusters are synthetized via a one-pot hydrothermal method. • The MWCNTs are introduced into the active materials to construct a 3D conductive network. • The remarkable pseudocapacitive effect is conducive to the rate performance. • The incomplete conversion for sodium storage at low voltage is revealed by the ex situ XANES test. • The sodium storage process with low-strain and high stability is observed by the in situ TEM image. [ABSTRACT FROM AUTHOR]

Abstract Metal selenides have received much attention from the rechargeable battery community owing to their considerable capacity. However, attainment of a long cycle life and fast Na+ storage kinetics are still needed to enable their practical application. Co 0.85 Se nanosheets prepared using a simple hydrothermal method exhibit a hierarchical porous structure, which is conducive to fast electrolyte transport and rapid adsorption of Na+ ions. Herein, to improve the electronic conductivity of Co 0.85 Se, reduced graphene oxide (rGO) is introduced to construct a three-dimensional network and achieve fast electronic transport. This defect-controlled Co 0.85 Se@rGO anode exhibits a highly reversible capacity of 460 mA h g−1 at a current density of 0.5 A g−1. Outstanding durability and remarkable rate stability are also achieved via the synergistic effects of vacancy transport and the heterostructure between Co 0.85 Se and rGO. Furthermore, the Na+ insertion/extraction mechanism is systematically investigated using ex situ X-ray diffraction, Raman spectroscopy, high-resolution transmission electron microscopy, and a series of electrochemical analyses. These analyses enable detailed characterization of the ionic diffusion kinetics and corresponding components and structural changes. Finally, a first-principles approach is employed to determine the diffusion energy barrier of Na+ ions in perfect CoSe and defective Co 0.85 Se. Graphical abstract The vertically oriented Co 0.85 Se ultrathin nanosheets loaded on rGO with hierarchical porous structure exhibited superior electrochemical performances, which can be ascribed to three reasons: (I) abundant pores is conducive to the fast Na+ transport and relieve volume expansion during sodiation/desodiation; (II) special morphology provides strong pseudo-capacitance effect; (III) vacancies with gradient concentration in Co 0.85 Se enhance sodium storage kinetics. fx1 Highlights • The hierarchical porous Co 0.85 Se nanosheets are prepared by the solvent-controlled hydrothermal method. • These voids not only accelerate the ion transfer in electrode but also reserve space for relieving the volume expansion. • The robust Se-C bonds construct fast electron transfer paths between the isolated Co 0.85 Se nanosheets. • The vertically orientated Co 0.85 Se nanosheets enhance the volume energy density and structural stability. • The superior sodium storage kinetics and reversible redox reactions were verified via the GITT, ex-situ measurements and DFT calculations. [ABSTRACT FROM AUTHOR]

The performance of a Prussian blue cathode is affected by its structure and stability. Through the inhibitor and temperature control, the border-rich structure was obtained, which provides a good contact between electrode-electrolyte interfaces and increases the transmission path for Na + ions. In addition, the as-prepared sample with rhombohedral phase demonstrated lower band gap and lower energy barrier for Na + ions insertion. Benefiting from the kinetics optimization, the as-prepared electrode exhibited initial capacity of 120 mA h g −1 and maintained nearly 80% after 280 cycles at current density of 100 mA g −1 . This electrode also exhibited good rate performance about 60 mA h g −1 at rate of 10 C. The structural stability is also related to the formation of the passivation layer during the charge-discharge process. The optimized passivation layer not only protects the electrode form the adverse side reactions at high voltage but also delivers low interface impedance. It can be inferred that the passivation layer plays a positive role in long cycling performance. When the as-prepared electrode was measured in an electrolyte with FEC additive, it exhibited a high capacity retention rate of 79% after 500 cycles. [ABSTRACT FROM AUTHOR]

China is beginning to transform from a migrant exporting country to a migrant importing country. Our study aimed to assess risks of imported tuberculosis among travellers and to determine risk factors, to tailor institutional guidelines. We conducted an observational, retrospective, population-based cohort study. Molecular epidemiology surveillance methods were used to screen travellers for cases of pulmonary tuberculosis (PTB) at Guangzhou Port in China from January 2010 to December 2016. A total of 165,369 travellers from 190 countries and regions were screened for PTB. The rate of suspected PTB, laboratory confirmed rate, and the total detection rate in emigrants were significantly higher than those in travellers (p<0.01). There were four differences in the PTB screening process between emigrants and travellers. According to the transmission risk degree of the tuberculosis, forty high-risk PTB importing countries were divided into five levels. The travellers diagnosed with PTB were significantly younger than the emigrants (p<0.01). The distribution of genotypes differed significantly between the travellers and emigrants (p< 0.001). PTB screening process in travellers at ports should include a risk assessment of high-risk groups. It should reduce diagnosis time by rapid molecular detection methods and strengthen drug resistant (DR) transmission and monitoring of imported PTB strains through molecular genotyping at ports. [ABSTRACT FROM AUTHOR]

A previously developed statistical model for transverse cracking in cross ply laminates is extended to oblique cracking in multidirectional laminates. The oblique cracks are assumed to form in a ply when the local in-plane tensile stress normal to fibers exceeds the transverse strength of the ply. This strength is assumed to have a statistical distribution given by a two-parameter Weibull function. The model is applied to a glass–epoxy [0/60 2 /0/−60 2 ] s laminate in which cracking evolution of the four −60° plies in the middle of the laminate is examined. The local stress field in the cracked −60° plies is calculated by a three-dimensional finite element method based on a unit cell construction developed by Li et al. [1] . The measured crack density is found to agree well with that calculated by the statistical model. [ABSTRACT FROM AUTHOR]

Abstract: We present a statistical analysis based methodology for making assessment of the manufacturing quality of cross ply composite laminates as it relates to its effect on transverse cracking evolution. Assuming a two-parameter Weibull distribution of tensile strength of the transverse plies to represent randomly distributed manufacturing defects, multiple crack formation in the plies is simulated in the non-interactive and interactive regimes of cracking using the local stress fields calculated by a variational analysis. The statistical methodology is demonstrated on crack density evolution in cross ply laminates manufactured by four different processing routes and loaded in monotonic tension in the axial direction. The differences in the crack density evolution, supposedly due to different defect population induced by the four manufacturing conditions, could be described by the proposed statistical simulation method. [Copyright &y& Elsevier]

At low concentrations zinc (Zn) is essential for plants and animals, but it becomes toxic when it exceeds a critical level. This study aimed to explore the effects of biochar on the remediation of Zn-polluted soil and the distribution of Zn in rice plants using pot experiments. Various amounts of biochar (0% (control), 2.5%, and 5% w/w) derived from rice straw were mixed with Zn-contaminated soil collected from farmland near a mine. The results showed that biochar enhanced the biomass of rice tissues and significantly reduced the concentration of Zn in brown rice. These results could be attributed to the combination of several effects: (1) Biochar increased the soil pH and organic carbon content, resulting in a reduction in the concentration of soil available Zn and transforming forms of immobilized Zn from acid soluble to reducible. (2) Biochar addition decreased the amorphous iron and complex iron concentrations in the soil solution and reduced the formation of root Fe plaques as well as the storage of Zn in iron plaques, thus diminishing the probability of Zn transfer from root surfaces to tissues. (3) Biochar played a key role in abating the toxic effect of Zn in rice plants as it decreased the transfer of Zn from roots to leaves and promoted Zn storage in the vacuoles of root cells. These results suggest that the application of biochar to Zn-contaminated soil is effective in reducing Zn accumulation in rice grains and can enhance rice production. [Display omitted] • Biochar enhanced plant biomass and decreased Zinc (Zn) accumulation in rice grain. • Biochar decreased the bioavailability of Zn in soils. • Biochar reduced the storage of Zn in iron plaques. • Biochar reduced the transfer of Zn from root to leaf. [ABSTRACT FROM AUTHOR]

From non-destructive and cross-sectional visualization by synchrotron X-ray tomography, we suggest a novel capacity decaying mechanism of all-solid-state Na batteries built with closo-borate electrolytes caused by electrochemically generated inactive Na electrodeposits. [Display omitted] • Na all-solid-state batteries (Na ASSBs) were built with the closo-borate solid electrolyte. • Noninvasive synchrotron X-ray tomography technique was used to study the decaying mechanisms of the cycled Na ASSBs. • Markov process model was employed to describe the physicochemical meaning of the observed capacity decay. • A new decaying mechanism of the Na ASSBs caused by the continuous accumulation of Na electrodeposits was proposed. [ABSTRACT FROM AUTHOR]

Hemicellulose is key in determining the fate of plant cell wall in almost all growth and developmental stages. Nevertheless, there is limited knowledge regarding its involvement in the development and ripening of banana fruit. This study investigated changes in the temporal-spatial distribution of various hemicellulose components, hemicellulose content, activities of the main hydrolysis enzymes, and transcription level of the main hemicellulose-related gene families in banana peels. Both hemicellulose and xylan contents were positively correlated to the fruit firmness observed in our previous study. On the contrary, the xylanase activity was negatively correlated to xylan content and the fruit firmness. The vascular bundle cells, phloem, and cortex of bananas are abundant in xyloglucan, xylan, and mannan contents. Interestingly, the changes in the signal intensity of the CCRC-M104 antibody recognizing non-XXXG type xyloglucan are positively correlated to hemicellulose content. According to RNA-Seq analysis, xyloglucan and xylan-related genes were highly active in the early stages of growth, and the expression of MaMANs and MaXYNs increased as the fruit ripened. The abundance of plant hormonal and growth-responsive cis -acting elements was detected in the 2 kb upstream region of hemicellulose-related gene families. Interaction between hemicellulose and cell wall-specific proteins and MaKCBP1/2, MaCKG1, and MaHKL1 was found. The findings shed light on cell wall hemicellulose's role in banana fruit development and ripening, which could improve nutrition, flavor, and reduce postharvest fruit losses. • Hemicellulose and xylan concentration positively linked with banana fruit firmness. • Xyloglucan recognized by CCRC-M104 was positively related to hemicellulose content. • The MaXYNs and MaMANs were increased significantly after fruit ripening. • The hormonal-responsive cis- elements were detected in high numbers. • The hemicellulose-related proteins strongly interacted with some growth-related ones. [ABSTRACT FROM AUTHOR]

Activation of the stimulator of interferon genes (STING) pathway by radiotherapy (RT) has a significant effect on eliciting antitumor immune responses. The generation of hydroxyl radical (·OH) storm and the sensitization of STING - relative catalytic reactions could improve radiosensitization-mediated STING activation. Herein, multi-functional radiosensitizer with oxygen vacancies depended mimicking enzyme-like activities was fabricated to produce more dsDNA which benefits intracellular 2′, 3′-cyclic GMP-AMP (cGAMP) generation, together with introducing exogenous cGAMP to activate immune response. MnO 2 @CeO x nanozymes present enhanced superoxide dismutase (SOD)-like and peroxidase (POD)-like activities due to induced oxygen vacancies accelerate the redox cycles from Ce4+ to Ce3+ via intermetallic charge transfer. CeO x shells not only serve as radiosensitizer, but also provide the conjugation site for AMP/GMP to form MnO 2 @CeO x -GAMP (MCG). Upon X-ray irradiation, MCG with SOD-like activity facilitates the conversion of superoxide anions generated by Ce - sensitization into H 2 O 2 within tumor microenvironment (TME). The downstream POD-like activity catalyzes the elevated H 2 O 2 into a profusion of ·OH for producing more damage DNA fragments. TME-responsive decomposed MCG could supply exogenous cGAMP, meanwhile the releasing Mn2+ improve the sensitivity of cyclic GMP-AMP synthase to dsDNA for producing more cGAMP, resulting in the promotion of STING pathway activation. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Electrolytes that possess both interfacial stability toward lithium metal anodes and compatibility with high voltage cathodes are required for high energy density batteries. Here a high concentration LiTFSI salt firstly dissolves in an ionic liquid Pyr1,3FSI. This electrolyte with synergetic effect of TFSI and FSI anions, which not only effectively suppresses lithium dendrite growth because of the highly concentrated solid electrolyte interphase film, but also beneficially improve the cycling performance of lithium batteries. Lithium plating/stripping tests reveal that the concentrated electrolyte has superior compatibility with a lithium metal anode than an electrolyte with low salt concentration. Furthermore, a lithium metal battery containing the electrolyte and a lithium cobalt oxide cathode achieves high coulombic efficiency and good cycling stability at 4.4 V and high temperature. These results indicate that the highly concentrated ionic liquid electrolyte is promising for use in lithium metal batteries. Graphical abstract Image 1 Highlights • High concentrated electrolyte synthesized with LiTFSI and ionic liquid Pyr1,3FSI. • High concentrated sample possess interfacial stability toward lithium metal anode. • High concentrated sample was used in a high-voltage LiCoO 2 /Li battery. • The lithium metal battery achieved a high coulombic efficiency at 60 °C. [ABSTRACT FROM AUTHOR]