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Disulfides are widely found in natural products and find a wide range of applications in life sciences, materials chemistry and other fields. The preparation of disulfides mainly rely on oxidative couplings of two sulfur containing compounds. This strategy has many side reactions and other shortcomings. Herein, we describe the reductive nickel-catalyzed cross-electrophile coupling of unactivated alkyl bromides with symmetrical alkyl- and aryltetrasulfides to form alkyl-alkyl and aryl-alkyl unsymmetrical disulfides. This approach for disulfide synthesis is practical, relies on easily available, unfunctionalized substrates, and is scalable. We investigated the mechanism of this transformation and found that the tetrasulfide compound does not selectively break the central S–S bond, but regio-selectively generates trisulfide intermediates. The preparation of disulfides mainly relies on oxidative couplings of two sulfur-containing compounds, a strategy which has side reactions and other shortcomings. In this work, the authors present a reductive nickel-catalyzed cross-electrophile coupling of unactivated alkyl bromides with symmetrical tetrasulfides to form unsymmetrical disulfides, proceeding via trisulfide intermediates.

Chalcogen-containing compounds have received considerable attention because of their manifold applications in agrochemicals, pharmaceuticals, and material science. While many classical methods have been developed for preparing organic sulfides, most of them exploited the transition-metal-catalyzed cross-couplings of aryl halides or pseudo halides with thiols or disulfides, with harsh reaction conditions usually being required. Herein, we present a user-friendly, nickel-catalyzed reductive thiolation of unactivated primary and secondary alkyl bromides with thiosulfonates as reliable thiolation reagents, which are easily prepared and bench-stable. Furthermore, a series of selenides is also prepared in a similar fashion with selenosulfonates as selenolation reagents. This catalytic method offers a facile synthesis of a wide range of unsymmetrical alkyl-aryl or alkyl-alkyl sulfides and selenides under mild conditions with an excellent tolerance of functional groups. Likewise, the use of sensitive and stoichiometric organometallic reagents can be avoided. Chalcogen-containing compounds find broad application in chemical industry. Here, the authors report a nickel-catalyzed reductive chalcogenation of unactivated alkyl bromides with thiosulfonates and selenosulfonates to access a range of unsymmetrical sulfides and selenides under mild conditions.

Background Dysfunctions of long non-coding RNA (lncRNAs) have been associated with the initiation and progression of hepatocellular carcinoma (HCC), but the clinicopathologic significance and potential role of lncRNA PTTG3P (pituitary tumor-transforming 3, pseudogene) in HCC remains largely unknown. Methods We compared the expression profiles of lncRNAs in 3 HCC tumor tissues and adjacent non-tumor tissues by microarrays. In situ hybridization (ISH) and quantitative real-time polymerase chain reaction (qRT-PCR) were applied to assess the level of PTTG3P and prognostic values of PTTG3P were assayed in two HCC cohorts ( n  = 46 and 90). Artificial modulation of PTTG3P (down- and over-expression) was performed to explore the role of PTTG3P in tumor growth and metastasis in vitro and in vivo. Involvement of PTTG1 (pituitary tumor-transforming 1), PI3K/AKT signaling and its downstream signals were validated by qRT-PCR and western blot. Results We found that PTTG3P was frequently up-regulated in HCC and its level was positively correlated to tumor size, TNM stage and poor survival of patients with HCC. Enforced expression of PTTG3P significantly promoted cell proliferation, migration, and invasion in vitro, as well as tumorigenesis and metastasis in vivo. Conversely, PTTG3P knockdown had opposite effects. Mechanistically, over-expression of PTTG3P up-regulated PTTG1, activated PI3K/AKT signaling and its downstream signals including cell cycle progression, cell apoptosis and epithelial-mesenchymal transition (EMT)-associated genes. Conclusions Our findings suggest that PTTG3P, a valuable marker of HCC prognosis, promotes tumor growth and metastasis via up-regulating PTTG1 and activating PI3K/AKT signaling in HCC and might represent a potential target for gene-based therapy.

Cinnamomi ramulus (CR) and Cinnamomi cortex (CC), both sourced from Cinnamomum cassia Presl, are commonly used Chinese medicines in the Chinese Pharmacopeia. However, while CR functions to dissipate cold and to resolve external problems of the body, CC functions to warm the internal organs. To clarify the material basis of these different functions and clinical effects, a simple and reliable UPLC-Orbitrap-Exploris-120-MS/MS method combined with multivariate statistical analyses was established in this study with the aim of exploring the difference in chemical compositions of aqueous extracts of CR and CC. As the results indicated, a total of 58 compounds was identified, including nine flavonoids, 23 phenylpropanoids and phenolic acids, two coumarins, four lignans, four terpenoids, 11 organic acids and five other components. Of these compounds, 26 significant differential compounds were identified statistically including six unique components in CR and four unique components in CC. Additionally, a robust HPLC method combined with hierarchical clustering analysis (HCA) was developed to simultaneously determine the concentrations and differentiating capacities of five major active ingredients in CR and CC: coumarin, cinnamyl alcohol, cinnamic acid, 2-methoxycinnamic acid and cinnamaldehyde. The HCA results showed that these five components could be used as markers for successfully distinguishing CR and CC. Finally, molecular docking analyses were conducted to obtain the affinities between each of the abovementioned 26 differential components, focusing on targets involved in diabetes peripheral neuropathy (DPN). The results indicated that the special and high-concentration components in CR showed high docking scores of affinities with targets such as HbA1c and proteins in the AMPK–PGC1–SIRT3 signaling pathway, suggesting that CR has greater potential than CC for treating DPN.

The development of highly efficient electrocatalysts for direct seawater splitting with bifunctionality for inhibiting anodic oxidation reconstruction and selective oxygen evolution reactions is a major challenge. Herein, we report a direct seawater oxidation electrocatalyst that achieves long-term stability for more than 1000 h at 600 mA/cm 2 @η 600 and high selectivity (Faraday efficiency of 100%). This catalyst revolves an amorphous molybdenum oxide layer constructed on the beaded-like cobalt oxide interface by atomic layer deposition technology. As demonstrated, a new restricted dynamic surface self-reconstruction mechanism is induced by the formation a stable reconstructed Co-Mo double hydroxide phase interface layer. The device assembled into a two-electrode flow cell for direct overall seawater electrolysis maintained at 1 A/cm 2 @1.93 V for 500 h with Faraday efficiency higher than 95%. Hydrogen generation rate reaches 419.4 mL/cm 2 /h, and the power consumption (4.62 KWh/m 3 H 2 ) is lower than that of pure water (5.0 KWh/m 3 H 2 ) at industrial current density. Chlorine evolution reaction and deep reconstruction of catalyst are critical issues in direct seawater electrolysis. Here, the authors propose a MoO 3 /CoO/carbon composite material for improved selective seawater oxidation and restricted dynamic surface self-reconstruction.

Purpose The purpose of this paper is to investigate how different forms of interpersonal conflicts and employees’ psychological empowerment may affect knowledge sharing intentions directly or indirectly via interpersonal trust in the workplace. Design/methodology/approach Survey data collected from 249 employees of 37 of the top 500 corporations in the manufacturing industry in Taiwan were used for the data analysis. The research model was analyzed using the component-based structural equation modeling technique, namely, the partial least squares (PLS) approach. Findings The results indicate that both relationship and task conflicts have significant indirect effects on employees’ knowledge sharing intentions via psychological empowerment and trust. Additionally, psychological empowerment significantly influences employees’ knowledge sharing intentions both directly and indirectly via trust. Research limitations/implications The primary theoretical implication is an advancement in the understanding of the critical antecedents of and their different effects on employees’ knowledge sharing intentions from the perspectives of conflict management and individual psychological empowerment. Future research may concentrate on investigating the bidirectional interactions among trust, relationship conflicts and task conflicts in different knowledge-sharing contexts. Practical implications This study provides practical insights into conflict resolution intended to facilitate psychological empowerment and interpersonal trust that encourage knowledge sharing in the workplace. Originality/value To the best of the authors’ knowledge, this study is the first knowledge sharing study that empirically examines how task and relationship conflicts affect employees’ knowledge sharing intentions differently via the mediation of their perceived psychological empowerment and interpersonal trust in one another in the workplace.

Acute kidney injury (AKI) has become a worldwide public health problem, but little information is available about the disease burden in China. We aimed to evaluate the burden of AKI and assess the availability of diagnosis and treatment in China. We launched a nationwide, cross-sectional survey of adult patients who were admitted to hospital in 2013 in academic or local hospitals from 22 provinces in mainland China. Patients with suspected AKI were screened out on the basis of changes in serum creatinine by the Laboratory Information System, and we reviewed medical records for 2 months (January and July) to confirm diagnoses. We assessed rates of AKI according to two identification criteria: the 2012 Kidney Disease: Improving Global Outcomes (KDIGO) AKI definition and an increase or decrease in serum creatinine by 50% during hospital stay (expanded criteria). We estimated national rates with data from the 2013 report by the Chinese National Health and Family Planning Commission and National Bureau of Statistics. Of 2 223 230 patients admitted to the 44 hospitals screened in 2013, 154 950 (7·0%) were suspected of having AKI by electronic screening, of whom 26 086 patients (from 374 286 total admissions) were reviewed with medical records to confirm the diagnosis of AKI. The detection rate of AKI was 0·99% (3687 of 374 286) by KDIGO criteria and 2·03% (7604 of 374 286) by expanded criteria, from which we estimate that 1·4–2·9 million people with AKI were admitted to hospital in China in 2013. The non-recognition rate of AKI was 74·2% (5608 of 7555 with available data). Renal referral was done in 21·4% (1625 of 7604) of the AKI cases, and renal replacement therapy was done in 59·3% (531 of 896) of those who had the indications. Delayed AKI recognition was an independent risk factor for in-hospital mortality, and renal referral was an independent protective factor for AKI under-recognition and mortality AKI has become a huge medical burden in China, with substantial underdiagnosis and undertreatment. Nephrologists should take the responsibility for leading the battle against AKI. National 985 Project of China, National Natural Science Foundation of China, Beijing Training Program for Talents, International Society of Nephrology Research Committee, and Bethune Fund Management Committee.

PurposeThis article aims at a Unified Theory of Acceptance and Use of Technology (UTAUT) model framework that was used to investigate the impact of a 16-h smartphone training program on the correlations among different constructs of smartphone use in a sample of older adults.Design/methodology/approachA total of 208 participants aged 60–78 (mean: 65.4) years completed a questionnaire that collected information on demographic variables and the frequency and duration of smartphone use as well as the answers to questions on the six UTAUT constructs of performance expectancy, effort expectancy, social influence, facilitating conditions, and behavioral intention and usage behavior. The data were analyzed using partial least squares analysis.FindingsThis study was the first to compare post-training changes in the correlations among UTAUT constructs. The results revealed significant post-training changes in all construct correlations. Behavioral intention and facilitating conditions were shown to significantly impact usage behavior both before and after training and performance expectancy was shown to impact behavioral intention before training. After training, both effort expectancy and social influence were found to impact behavioral intention significantly. Moreover, the impact of facilitating conditions on usage behavior was significantly increased after training.Originality/valueTo date, no study published in the literature has investigated the impact of technological training on the technology-use intentions and behaviors of older adults. The findings of this study suggest that, for older adults, the results of the acceptance and use model for smartphones change significantly and positively between pre-smartphone training and post-smartphone training time points. The findings support that technology training has a positive impact on smartphone use in older adults.

Lithium–sulfur battery possesses high energy density but suffers from severe capacity fading due to the dissolution of lithium polysulfides. Novel design and mechanisms to encapsulate lithium polysulfides are greatly desired by high-performance lithium–sulfur batteries towards practical applications. Herein, we report a strategy of utilizing anthraquinone, a natural abundant organic molecule, to suppress dissolution and diffusion of polysulfides species through redox reactions during cycling. The keto groups of anthraquinone play a critical role in forming strong Lewis acid-based chemical bonding. This mechanism leads to a long cycling stability of sulfur-based electrodes. With a high sulfur content of ~73%, a low capacity decay of 0.019% per cycle for 300 cycles and retention of 81.7% over 500 cycles at 0.5 C rate can be achieved. This finding and understanding paves an alternative avenue for the future design of sulfur–based cathodes toward the practical application of lithium–sulfur batteries. Novel cathode design holds the key to enabling high performance lithium-sulfur batteries. Here the authors utilize anthraquinone to chemically stabilize polysulfides, revealing that the keto groups of anthraquinone play a critical role in forming strong Lewis acid-based chemical bonding.

Centrosymmetric materials with site inversion asymmetries possess hidden spin polarization, which remains challenging to be converted into spin currents because the global inversion symmetry is still conserved. This study demonstrates the spin-polarized circular photocurrents in centrosymmetric transition metal dichalcogenide semiconductors at normal incidence without applying electric bias. The global inversion symmetry is broken by using a spatially-varying circularly polarized light beam, which could generate spin gradient owing to the hidden spin polarization. The dependence of the circular photocurrents on electrode configuration, illumination position, and beam spot size indicates an emergence of circulating electric current under spatially inhomogeneous light, which is associated with the deflection of spin-polarized current through the inverse spin Hall effect. The circular photocurrents is subsequently utilized to probe the spin polarization and the inverse spin Hall effect under different excitation wavelengths and temperatures. The results of this study demonstrate the feasibility of using centrosymmetric materials with hidden spin polarization and non-vanishing Berry curvature for spintronic device applications. The authors report the generation of circular photocurrents from multilayer 2H-phase transition metal dichalcogenides, including MoTe 2 , MoS 2 , and WSe 2 , which is attributed to the manifestation of hidden spin polarization and inverse spin Hall effect.