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To improve the resilience of railway stations, a typical station was selected as the research object, and an isolation design was introduced. Twenty-four groups of near-fault pulse-like ground motions were selected. The seismic resilience of the no-isolation railway stations (NIRS) and the isolation railway stations (IRS) were compared to provide a numerical result of the improvement in resilience. The results show that in the station isolation design, the station's functional requirements and structural characteristics should be considered and the appropriate placement of isolation bearings is under the waiting room. Under the action of a rare earthquake, the repair cost, repair time, rate of harm and death of the IRS were decreased by 8.04 million, 18.30 days, 6.93×10−3 and 1.21×10−3, respectively, when compared to the NIRS. The IRS received a seismic resilience grade of three-stars and the NIRS only one-star, indicating that rational isolation design improves the seismic resilience of stations. Thus, for the design of stations close to earthquake faults, it is suggested to utilize appropriate isolation techniques to improve their seismic resilience. [ABSTRACT FROM AUTHOR]

The Southeast (SE) Asian tin belt is a major tin producer globally, with a prolonged mineralization history from the Permian to Paleogene (ca. 285-45 Ma). Tin deposits in this region are typically associated with tectonic settings that involve subduction and collision of the Paleo-, Meso-, and Neo-Tethys slabs. Ca. 40 Ma, a notable transition occurred in the tectonic regime of SE Tibet, with the Neo-Tethys subduction giving way to lateral extrusion of the Indochina block along major strike-slip faults. Previously, it was believed that this shift had brought tin mineralization to a halt. In this study, we present in situ laser ablation-inductively coupled plasma-mass spectrometry U-Pb cassiterite ages of 21-19 Ma from the Yunling tin deposit located in western Yunnan, China. Yunling produces gem-quality cassiterite that is transparent but contains low U contents, which renders usual U-Pb dating techniques unusable. To address this, a customized dating protocol involving cathodoluminescence (CL) imaging and testing of U distribution on crystallographically welldefined cassiterite crystals was applied. The study revealed two types of primary microstructures in cassiterite: volumetrically dominant concentric oscillatory growth zones and subordinate CL-dark sector zones. The U content shows a preferential enrichment in the CL-dark sector zones, typically tens of parts per million (ppm), which is two orders of magnitude greater than the U content in the concentric zone. This is significant, as the dating results (21-19 Ma) obtained through the targeted selection of CL-dark sector zones represent the youngest tin mineralization event in the SE Asian tin belt. Additionally, these results challenge the established belief that the ore-hosting Indosinian granite, dated to ca. 215 Ma, was related to Sn mineralization in the Yunling area. We suggest that emplacement of the early Neogene Sn mineralization at Yunling may be genetically connected to extensive delamination of the lithosphere in southeastern Tibet. The lithospheric delamination led to the upwelling and decompression partial melting of the asthenosphere, which provides a plausible explanation for the high temperature required for the release of Sn from biotite-dehydration melting of sedimentary protolith. The study also highlights the potential of Oligocene-Miocene-aged granites situated in the Sanjiang Tethys and adjacent areas of western Yunnan as prospective exploration targets for tin mineralization. [ABSTRACT FROM AUTHOR]

OBJECTIVE To compare the acute strength (failure load and work to failure) of standard incisional gastropexy (SIG) and modified incisional gastropexy (MIG). ANIMALS 37 pig cadavers. PROCEDURES Stomachs and right abdominal walls were harvested from pigs euthanized for reasons unrelated to this study. The tissues were stored in lactated Ringer's solution overnight in a 5 °C cooler. Matching body wall and stomach tissue pairs were randomized and divided into 2 groups, on which either SIG or MIG was performed the following day. The MIG technique was identical to SIG except 2 additional simple interrupted sutures, 1 cranial and 1 caudal to the continuous suture line, were placed full thickness into the stomach to ensure engagement of the submucosa. After gastropexy, the samples underwent biomechanical testing. Information regarding change in position and load was generated by the MTESTQuattro software. Mode of failure was examined after the procedure was complete. RESULTS The MIG had higher failure load and work to failure compared to SIG. All failures were caused by gastric tissue tearing. CLINICAL RELEVANCE The MIG is biomechanically superior to SIG and may provide more security than SIG during healing. However, clinical study is needed to ascertain if there isa difference in gastropexy failure and complications between these 2 techniques. [ABSTRACT FROM AUTHOR]

OBJECTIVE To compare complications between a modified incisional gastropexy (MIG) technique and standard incisional gastropexy (SIG). ANIMALS 347 client-owned dogs. PROCEDURES Dogs that had undergone SIG or MIG from March 2005 through April 2019 were identified through a medical record search of the University of Missouri Veterinary Health Center. The MIG technique is identical to SIG except 2 additional simple interrupted sutures are added, 1 cranial and 1 caudal to the continuous suture line, going full thickness into the stomach to ensure engagement of submucosa. Medical record information was used to identify intraoperative, postoperative, and short-term complications, and telephone or email communication to pet owners and/or referring veterinarians was used to identify complications (short-term and long-term) after discontinuance of care at the University of Missouri Veterinary Health Center. Intraoperative, postoperative, short-term, and long-term complications were analyzed in aggregate within 6 matched groupings: (1) gastropexy for gastric dilatation-volvulus, (2) prophylactic gastropexy without other procedures, (3) gastropexy with ovariohysterectomy, (4) gastropexy with castration, (5) gastropexy with splenectomy, and (6) gastropexy with celiotomy other than splenectomy. Overall rates of complications potentially attributed to gastropexy were compared between SIG and MIG using the Fisher exact test. Overall rates of complications not attributed to gastropexy were compared between SIG and MIG using the X² test. RESULTS There were no significant differences in overall complication rates between SIG and MIG. CLINICAL RELEVANCE Surgeons who feel that engagement of gastric submucosa is important for gastropexy success may use the MIG technique with minimal fear of complications. However, superiority of one technique over the other cannot be determined on the basis of this study. [ABSTRACT FROM AUTHOR]

Patients with device detected atrial high-rate episodes (AHRE) have an increased risk of MACE. The R2CHA2DS2-VASc, CHADS2, R2CHADS2 and CHA2DS2-VASc score have been investigated for predicting major adverse cardiovascular events (MACE) in different groups of patients. We aimed to evaluate the R2CHA2DS2-VASc score in combination with AHRE ≥ 6 min for predicting MACE in patients with dual-chamber PPM but no prior atrial fibrillation (AF). We retrospectively enrolled 376 consecutive patients undergoing dual-chamber PPM implantation and no prior AF. The primary endpoint was subsequent MACE. For all patients in the cohort, CHADS2, R2CHADS2, CHA2DS2-VASc, R2CHA2DS2-VASc scores and AHRE ≥ or < 6 min were determined. AHRE was recorded as a heart rate > 175 bpm (Medtronic) or > 200 bpm (Biotronik) lasting ≥ 30 s. Multivariate Cox regression analysis with time-dependent covariates was used to determine the independent predictors of MACE. ROC-AUC analysis was performed for CHADS2, R2CHADS2, CHA2DS2-VASc, and R2CHA2DS2-VASc scores and then adding AHRE ≥ 6 min to the four scores. The median age was 77 years, and 107 patients (28.5%) developed AHRE ≥ 6 min. After a median follow-up of 32 months, 46 (12.2%) MACE occurred. Multivariate Cox regression analysis showed that R2CHA2DS2-VASc score (HR, 1.485; 95% CI, 1.212–1.818; p < 0.001) and AHRE ≥ 6 min (HR, 2.125; 95% CI, 1.162–3.887; p = 0.014) were independent predictors for MACE. The optimal R2CHA2DS2-VASc score cutoff value was 4.5 (set at ≥ 5), with the highest Youden index (AUC, 0.770; 95% CI, 0.709–0.831; p < 0.001). ROC-AUC analysis of the four risk scores separately combined with AHRE ≥ 6 min all showed better discriminatory power than the four scores alone (All Z-statistic p < 0.05). In patients with PPM who develop AHRE ≥ 6 min, it is crucial to perform risk assessment with either four scores to further stratify risk for MACE. [ABSTRACT FROM AUTHOR]

The innovative design of microstructure topology is of great significance to improve the energy absorption performance of honeycombs. In this paper, by embedding a hexagonal substructure in each inclined wall of the traditional reentrant (RE) honeycomb, a novel auxetic honeycomb, called reentrant combined-wall (RCW) honeycomb, is developed for improving energy absorption. Combining the experimental methods, numerical simulations, and analytical analyses, we systematically studied the in-plane quasi-static behaviors of the proposed honeycomb structure. It can be found that the deformation of the RCW honeycomb has a transitional stage, which makes a significant stress enhancement. During the crushing process, the Poisson's ratio of the RCW honeycomb keeps negative and is lower than that of the RE honeycomb. Besides, numerical and analytical analyses show that the stress-strain response of the RCW honeycomb has a good designability. Further, the analysis of specific energy absorption (SEA) is also performed, in which the RCW honeycomb shows a significant superiority over the RE honeycomb, with the SEA value almost twice that of the latter. Therefore, it can be concluded that the proposed novel structure has tangible improvements in the crushing strength, auxetic performance, and energy absorption, which deserves more attention in future work. [ABSTRACT FROM AUTHOR]

Fertility and longevity of hydrothermal systems are key parameters required to improve our ability in predicting new deposits and directly extracting metals from metalliferous fluids. Reconstructing evolutional trajectories of metalliferous fluids with high temporal resolution is critical for pushing our understanding forward, but this is inevitably challenging because traditional approaches for obtaining this information either have poor temporal resolution and/or bear considerable uncertainties. We present a novel approach (translating texturecontrolled information to temporal patterns) to reconstruct the thermal and isotopic history of the Weilasituo vein-type tin deposit (Inner Mongolia, China) at the millennial scale. In situ oxygen isotope thermometry of paragenetically constrained quartz and cassiterite reveals that tin deposition was accompanied by gradual cooling of pure magmatic fluids from ∼500 °C to ∼390 °C at lithostatic conditions, while fluid mixing and/or water-rock interaction were not required. The system then transitioned to hydrostatic conditions and permitted penetration of meteoric water and further cooling. Aluminum diffusion in quartz chronometry yields time scales of ∼50 k.y., ∼5 k.y., and ∼200 k.y. for pre-, syn-, and post-ore stages, respectively. Our results highlight that the magmatic-hydrothermal system did not form ore minerals for most of its lifetime, with mineralization occurring only briefly (i.e., <5% of its lifetime). Hence, the rates and efficiency of ore formation may need significant revision. For magmatichydrothermal systems with felsic magmas being stored at high crystallinity after extensive volatile exsolution, the efficiency of scavenging metals from melts to fluids critically controls their fertility. To directly extract metals from metalliferous fluids, the key is targeting systems with a high degree of magma crystallization (e.g., higher metal contents in fluids) in warm crust (e.g., able to sustain long-lived systems). [ABSTRACT FROM AUTHOR]

Herbal medicine (HM) is a type of medicine that uses active ingredients made from plants to treat diseases and maintain health and wellbeing. Due to its increasing worldwide usage, the possibility of HMs and conventional drugs being concurrently used is high, potentially leading to adverse events resulting from herb-drug interactions. Despite the safety concerns regarding such interactions, few studies have been conducted for assessing clinical consequences of using HMs with conventional drugs in real-world settings. As clinical trials are not forthcoming rapidly enough to provide the evidence for herb-drug interactions, observational studies are considered as an alternative approach. The present review focuses on evaluating the utility of analyzing real-world data in observational research to study the clinical consequences of herb-drug interactions between HMs and conventional drugs. The data sources and study designs of each highlighted literature are examined based on its strengths and limitations in analyzing herb-drug interactions. Finally, future observational studies involving novel and rigorous methodologies that may be effective in studying herb-drug interactions are discussed. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of acupuncture on brain function in patients with schizophrenia in remission. Methods: A total of 101 patients with schizophrenia in remission were selected in this study. The patients were randomly divided into the control group (n = 51) and the treatment group (n = 50). Patients in the control group were treated with antipsychotics, while patients in the treatment group were treated with acupuncture on the basis of antipsychotics treatment in the control group. Clinical therapeutic effect of the two groups was observed and compared. Moreover, 10 patients were randomly selected from each of the two groups to collect data of the resting state functional magnetic resonance imaging (fMRI) before and after treatment to judge the effect of brain function. Results: The scores of CGI scale of the patients in the two groups decreased after treatment compared with those before treatment, and the differences were statistically significant (P < 0.05). Compared with the control group after treatment, the scores of CGI scale of patients in the treatment group after treatment significantly decreased, and the difference was statistically significant (P < 0.05). According to the analysis of low-frequency amplitude (ALEF) in the fMRI results, the significant effect of acupuncture mainly reflected in the left occipital parietal lobe. According to the analysis of local consistency (ReHo), the significantly improved area of patient in the treatment group was the left occipital lingual gyrus. Conclusion: Acupuncture can improve the clinical therapeutic effect of patients with schizophrenia in remission, and it has relative stimulating effect on the spontaneous neuronal activity of patients. Moreover, it can provide an adjuvant therapeutic option for patients with schizophrenia. In addition, it can promote the clinical development of integrated Traditional Chinese and Western medicine. [ABSTRACT FROM AUTHOR]

The article develops a transformable microfluidic chip, named TransfOrigami microfluidics (TOM), by integrating stimuli-responsive materials with a thin and foldable microfluidic chip. Topics discussed include TOM's application as an environmentally adaptive photomicroreactor, complex vasculature of plants, and environmentally responsive morphing of the TOM.

Blockchain, the underlying technology of Bitcoin, has been deeply studied in various fields after its development in recent years. As a typical decentralized distributed data storage system, consensus reached among all participants in a blockchain system requires a consensus mechanism to be realized. In order to make blockchain applicable to different application scenarios, different consensus mechanisms have been proposed. With the further development of blockchain applications, more and more studies have been conducted on the consensus mechanism. However, some existing consensus mechanisms still have some problems in various aspects. Therefore, this paper proposes a trade deal algorithm based on the blockchain mechanism of consensus. First of all, according to PBFT, the lack of a dynamic problem in the VPBFT voting mechanism was introduced. The node system is divided into four types with different responsibilities and gives the number of relations between nodes. When the number of nodes is changed, it can be calculated according to the quantity relation, ensuring dynamic. Second, a data anonymous transaction and authentication protocol is designed. In the protocol, when the seller sells data, the mapping relationship between the real identity and the false identity of the data owner is blinded and sent to the buyer. When the buyer wants to verify their identity, the seller's identity can only be verified with the authentication of the blockchain. The proposed algorithm is superior to the current consensus in terms of time and energy consumption, throughput, and fault tolerance methods, which is proven through experimental tests and simulation analysis. [ABSTRACT FROM AUTHOR]

The article "Metabolism score for visceral fat (METS-VF): an innovative and powerful predictor of stroke" published in the Archives of Medical Science discusses the significance of cardiovascular diseases, particularly among middle-aged and older individuals. The study introduces METS-VF, a new visceral fat prediction index, and explores its association with cardiovascular events. Using data from the China Health and Retirement Longitudinal Study, the study aims to establish a prospective cohort to examine the relationship between METS-VF and cardiovascular diseases, highlighting the importance of reducing visceral fat and triglyceride levels to prevent these diseases. [Extracted from the article]

Poor sleep quality (PSQ) can have long-term effects leading to serious health issues. As more people turn to nonmedical treatments, including the use of music for improving sleep quality, health professionals need to be aware of how to use music effectively. This systematic literature review investigated, synthesized, and analyzed 56 studies concerning the impact of music on sleep quality that were published between January 2007 and December 2019. The authors found the studies: (a) were conducted by a variety of research disciplines from multiple countries; (b) investigated a large number of participants from various clinical and non-clinical populations; (c) employed an array of research designs, interventions, measurement tools, and rationales for music choice, and (d) found mostly positive results. Of the 56 studies, 52 (92.9%) showed a positive influence of music on sleep quality, while 4 (7.1%) found no impact. Seven (12.5%) articles reported that music had a greater or equal impact on sleep quality compared to other treatments. Future research should include more detailed descriptions of music interventions in order to find the most effective music interventions for improving the sleep quality of different populations. [ABSTRACT FROM AUTHOR]

The electrochemical migration (ECM) problem caused by corrosion is one of the most serious threats to the reliability of electronic equipments in a harsh condition. In this paper, the Al 2 O 3 , TiO 2 and ZrO 2 inorganic coating with a thickness of 1 μm deposited by magnetron sputtering technique are used to protect SAC305 solder alloy against ECM corrosion failure. Then the surface topographies, surface roughness and thickness of the coating are observed through atomic force microscopy and scanning electron microscopy. The thin electrolyte film containing chloride experiments are used to simulate the marine atmospheric environment to inspect the protection performance of the coatings. The results show that these coatings can inhibit ECM process and extend the time to short circuit to some extent. Specifically, TiO 2 has the most excellent protective properties, followed by ZrO 2. Moreover, the protection performances of these coatings are also further compared through adsorption energy of chloride on the coatings surface calculation, and the result indicates that Cl− is more easily absorbed on the surface of Al 2 O 3 , which also implies that the Al 2 O 3 has poorer protection property than TiO 2 and ZrO 2. [ABSTRACT FROM AUTHOR]

In this paper, for some typical local slump problems, through the site survey of engineering conditions, we observe the local slumping parts, collect a large number of production data, and adopt the Chiping polar projection method to evaluate the initial stability of the problem area. The unstable structure is combined with the solid scale projection to analyze the sliding direction, the sliding surface, the sliding amount, and the like. The study has a clearer understanding of the local slump problem, and based on the stability judgment results, combined with the site conditions, ultimately serves the engineering examples. [ABSTRACT FROM AUTHOR]

Glucagon-like peptide-1 (GLP-1) is a 30-amino acid peptide hormone that is mainly expressed in the intestine and hypothalamus. In recent years, basic and clinical studies have shown that GLP-1 is closely related to lipid metabolism, and it can participate in lipid metabolism by inhibiting fat synthesis, promoting fat differentiation, enhancing cholesterol metabolism, and promoting adipose browning. GLP-1 plays a key role in the occurrence and development of metabolic diseases such as obesity, nonalcoholic fatty liver disease, and atherosclerosis by regulating lipid metabolism. It is expected to become a new target for the treatment of metabolic disorders. The effects of GLP-1 and dual agonists on lipid metabolism also provide a more complete treatment plan for metabolic diseases. This article reviews the recent research progress of GLP-1 in lipid metabolism. [ABSTRACT FROM AUTHOR]

Granite-related wolframite-quartz veins are the world's most important tungsten mineralization and production resource. Recent progress in revealing their hydrothermal processes has been greatly facilitated by the use of infrared microscopy and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) analysis of both quartz- and wolframite-hosted fluid inclusions. However, owing to the paucity of detailed petrography, previous fluid inclusion studies on coexisting wolframite and quartz are associated with a certain degree of ambiguity. To better understand the fluid processes forming these two minerals, free-grown crystals of intergrown wolframite and quartz from the giant Yaogangxian W deposit in South China were studied using integrated in situ analytical methods including cathodoluminescence (CL) imaging, infrared microthermometry, Raman microspectroscopy, and fluid inclusion LA-ICP-MS analysis. Detailed crystal-scale petrography with critical help from CL imaging shows repetition of quartz, wolframite, and muscovite in the depositional sequence, which comprises a paragenesis far more complex than previous comparable studies. The reconstruction of fluid history in coexisting wolframite and quartz recognizes at least four successive fluid inclusion generations, two of which were entrapped concurrently with wolframite deposition. Fluctuations of fluid temperature and salinity during precipitation of coexisting wolframite and quartz are reflected by our microthermometry results, according to which wolframite-hosted fluid inclusions do not display higher homogenization temperature or salinity than those in quartz. However, LA-ICP-MS analysis shows that both primary fluid inclusions in wolframite and quartz-hosted fluid inclusions associated intimately with wolframite deposition are characterized by strong enrichment in Sr and depletion in B and As compared to quartz-hosted fluid inclusions that are not associated with wolframite deposition. The chemical similarity between the two fluid inclusion generations associated with wolframite deposition implies episodic tungsten mineralization derived from fluids exhibiting distinct chemical signatures. Multiple chemical criteria including incompatible elements and Br/Cl ratios of fluid inclusions in both minerals suggest a magmatic-sourced fluid with the possible addition of sedimentary and meteoric water. Combined with microthermometry and Raman results, fluid chemical evolution in terms of B, As, S, Sr, W, Mn, Fe, and carbonic volatiles collectively imply fluid phase separation and mixing with sedimentary fluid may have played important roles in wolframite deposition, whereas fluid cooling and addition of Fe and Mn do not appear to be the major driving factor. This study also shows that fluid inclusions in both wolframite and coexisting quartz may contain a substantial amount of carbonic volatiles (CO2 ± CH4) and H3BO3. Ignoring the occurrence of these components can result in significant overestimation of apparent salinity and miscalculation of LAICP-MS elemental concentrations. We suggest that these effects should be considered critically to avoid misinterpretation of fluid inclusion data, especially for granite-related tungsten-tin deposits. [ABSTRACT FROM AUTHOR]

Abstract To improve the corrosion resistance and electrical conductivity of 316L stainless steel used as a bipolar plate, TiN and ZrN coatings are deposited on the surface through magnetron sputtering in this study. Subsequently, the surface topography, composition, corrosion resistance, and interfacial contact resistance of the coated samples are characterized. The results show that the TiN and ZrN coating can significantly enhance the corrosion resistance of the 316L stainless steel. The corrosion current density of the coated 316L stainless steel with TiN and ZrN in the simulated cathodic environment of a proton-exchange membrane fuel cell (PEMFC) is 0.099 μA/cm2 and 0.209 μA/cm2, respectively, which meets the U.S. DOE 2020 target (<1 μA·cm−2). The EIS and polarization curves show that the TiN coating has better corrosion resistance than that of the ZrN coating. Moreover, the contact angle results indicate that TiN and ZrN can also improve the hydrophobicity of the stainless steel. The interfacial contact resistance between the TiN-coated sample and carbon paper before and after polarization is the smallest, which satisfies the U.S. DOE requirement (≤10 mΩ·cm2). Highlights • Uniform TiN and ZrN coating are deposited by reactive magnetron sputtering. • TiN and ZrN coating improve obviously the corrosion resistance and conductivity. • ICR and corrosion current of TiN coated sample meet the goal of DOE. [ABSTRACT FROM AUTHOR]

Abstract In this study, plasma electrolytic nitriding technology and an annealing treatment are used to modify titanium bipolar plates. Subsequently, the surface topography, corrosion resistance, and interfacial contact resistance of the nitrided samples are characterized. The results show that the nitrided layer consists of porous volcano-like micro-nano structure surface layer and the dense inner layer. Compared to the blank sample (87.9°±1.7°), the contact angle between the nitrided samples with annealing and deionized water significantly increases (104.7°±1.4° (nitrided for 15 min), 114.3 ± 3.0° (nitrided for 30 min)). The results of the electrochemical and atomic force microscopy analysis indicate that the nitrided samples with annealing have good corrosion resistance. The corrosion potential and corrosion current density of the nitrided samples with annealing are −0.016 V (Ag/AgCl) and 0.275 μA cm−2 (nitrided for 15 min) and 0.04 V (Ag/AgCl) and 0.195 μA cm−2 (nitrided for 30 min), respectively, which satisfy the requirement of DOE 2020 target (<1 μA cm−2). After potentiostatic polarization at 600 mV (SCE) in the simulated environment, the contact resistance of the samples remains very low (6.47 mΩ cm2 (nitrided for 15 min) and 3.91 mΩ cm2 (nitrided for 30 min)) and also satisfies the requirement of the DOE (≤10 mΩ cm2). Highlights • Plasma electrolytic nitriding technique was used to modify titanium bipolar plates. • Nitriding and annealing treatment improved significantly the corrosion resistance. • ICR of nitrided samples with annealing met the goal of DOE. [ABSTRACT FROM AUTHOR]

This paper develops a new method for estimating the elastic-plastic buckling strength of the truss structures under the static and seismic loads. Firstly, a new method for estimating the buckling strength of the truss structures was derived based on the buckling strength of the representative member considering the parameters, such as the structure configurations, boundary conditions, etc. Secondly, the new method was verified through the buckling strength estimation and the finite element method (FEM) analysis of the single member models, portal frame models and simple truss models. Finally, the method was applied to evaluate the buckling strength of a simple truss structure under seismic load, and the failure loads between the proposed method and the FEM were analyzed reasonably. The results show that the new method is feasible and reliable for structure engineers to estimate the buckling strengths of the truss structures under the static loads and seismic loads. [ABSTRACT FROM AUTHOR]

The transition-metal-catalyzed reaction of diazo compounds with arenes or heteroarenes is an efficient and straightforward approach to functionalize aromatic compounds. This digest summarizes recent progresses on transition-metal-catalyzed asymmetric reactions of diazo compounds with electron-rich (hetero-) arenes, including C–H functionalization, cascade reaction, cyclopropanation, cycloaddition, Buchner reaction and intramolecular dearomatization. [ABSTRACT FROM AUTHOR]

Metal-coordinating compounds are generally known to have strong smells, a phenomenon that can be attributed to the fact that odorant receptors for intense-smelling compounds, such as those containing sulfur, may be metalloproteins. We previously identified a mouse odorant receptor (OR), Olfr1509, that requires copper ions for sensitive detection of a series of metal-coordinating odorants, including (methylthio)methanethiol (MTMT), a strong-smelling component of male mouse urine that attracts female mice. By combining mutagenesis and quantum mechanics/molecular mechanics (QM/MM) modeling, we identified candidate binding sites in Olfr1509 that may bind to the copper-MTMT complex. However, whether there are other receptors utilizing metal ions for ligand-binding and other sites important for receptor activation is still unknown. In this study, we describe a second mouse OR for MTMT with a copper effect, namely Olfr1019. In an attempt to investigate the functional changes of metal-coordinating ORs in multiple species and to decipher additional sites involved in the metal effect, we cloned various mammalian orthologs of the 2 mouse MTMT receptors, and a third mouse MTMT receptor, Olfr15, that does not have a copper effect. We found that the function of all 3 MTMT receptors varies greatly among species and that the response to MTMT always co-occurred with the copper effect. Furthermore, using ancestral reconstruction and QM/MM modeling combined with receptor functional assay, we found that the amino acid residue R260 in Olfr1509 and the respective R261 site in Olfr1019 may be important for receptor activation. [ABSTRACT FROM AUTHOR]

Granular activated carbon (GAC) supported ZnO catalyst (ZnO-GAC) was prepared to activate persulfate (PS) for the decolorization of Acid Orange 7 (AO7) in the presence of ultrasonic irradiation (US). The effects of initial pH, PS concentration, catalyst dosage, initial dye concentration, and reaction temperature were investigated. The results showed that the decolorization efficiency increased with the increase of catalyst dosage and temperature, but decreased with the increase of initial dye concentration and initial pH, and the optimal PS concentration for color removal was 0.5 g L −1 . Radical quenching tests were performed by using ethanol, tert -butanol and phenol to verify the formation of sulfate radicals and hydroxyl radicals in the US/ZnO-GAC/PS process. Under the optimal conditions, 91.2% of decolorization was achieved and 83.1% of TOC was removed after 60 min treatment. Activated sludge inhibition tests were carried out to monitor the change of toxicity during the treatment of AO7 solution. [ABSTRACT FROM AUTHOR]

A two-dimensional (2D) heterobilayer system consisting of MoS2 on WSe2, deposited on epitaxial graphene, is studied by scanning tunneling microscopy and spectroscopy at temperatures of 5 and 80 K. A moiré pattern is observed, arising from lattice mismatch of 3.7% between the MoS2 and WSe2. Significant energy shifts are observed in tunneling spectra observed at the maxima of the moiré corrugation, as compared with spectra obtained at corrugation minima, consistent with prior work. Furthermore, at the minima of the moiré corrugation, sharp peaks in the spectra at energies near the band edges are observed for spectra acquired at 5 K. The peaks correspond to discrete states that are confined within the moiré unit cells. Conductance mapping is employed to reveal the detailed structure of the wave functions of the states. For measurements at 80 K, the sharp peaks in the spectra are absent, and conductance maps of the band edges reveal little structure. [ABSTRACT FROM AUTHOR]

Cibotium barometz is mainly distributed in eastern, southern, and southwest China as an important industrial export crop of great economical and medicinal value. The rhizome of C. barometz is widely used in Traditional Chinese Medicine clinics to treat conditions such as lumbago, limb-ache, rheumatism, and sciatica. In this study, the results of in vivo pharmacological experiments conclusively demonstrated that crude saccharides from C. barometz (CBB) exhibited osteoprotective effects in ovariectomized rats, which significantly increased bone mineral content (BMC) and bone mineral density (BMD), and prevented damage of the trabecular bone, consequently improving its biomechanical properties. To investigate the biological active ingredient(s), a novel oligo-glucomannan (denoted CBBP-1) was isolated and purified from CBB via anion-exchange and size-exclusion chromatography. Structural analysis indicated that CBBP-1 consisted of (1 → 4)-linked α- d -glucose, (1 → 6)-linked β - d -glucose with (1 → 3, 6)-linked α- d -mannose, and a terminal α- d -glucose. Morphological analysis revealed that CBBP-1 had an irregular sheet structure. Furthermore, osteoblastic MC3T3-E1 cells treated with CBBP-1 had significantly increased mRNA expression of runt-related transcription factor 2 , osterix , osteopontin , osteocalcin , and bone sialoprotein , indicating that CBBP-1 may stimulate osteoblastic differentiation. In conclusion, this study provides evidence that CBBP-1 may have potential as an anti-osteoporosis agent in the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

The role played by mould in the electrochemical migration (ECM) behaviour of an immersion silver finished printed circuit board (PCB-ImAg) under a direct current (DC) bias was investigated. An interesting phenomenon is found whereby mould, especially Aspergillus niger , can preferentially grow well on PCB-ImAg under electrical bias and then bridge integrated circuits and form a migration path. The cooperation of the mould and DC bias aggravates the ECM process occurring on PCB-ImAg. When the bias voltage is below 15 V, ECM almost does not occur for Ag coating. Mechanisms that explain the ECM processes of PCB-ImAg in the presence of mould and DC bias are proposed. [ABSTRACT FROM AUTHOR]

This work studied the effects of Nd on the corrosion behavior of a SAC305 alloy. The results show that the undercooling in solidification process decreases to 1.5–2.5 ℃ with Nd addition. The corrosion resistance of the solder with Nd is markedly enhanced, which is reflected in the following aspects: (1) the potential difference between IMCs and Sn drops to 14.4 mV and lessens the galvanic corrosion sensitivity; (2) the thickness of the passivation film increases; and (3) the proportion of SnO 2 in corrosion product layer in the pseudopassivation region increases. Specifically, 0.05 wt% Nd addition can provide the best improvement effects. [Display omitted] • 0.05 wt% Nd addition can provide the best improvement effects. • Nd addition decreases the potential difference between the IMCs and Sn. • Nd addition increases the thickness of the passivation film on solder alloy surface. • Nd addition enhances the proportion of SnO 2 in corrosion products layer. [ABSTRACT FROM AUTHOR]

The semiconductor properties and protective role of a single-component Cu 2 O layer were studied using cyclic voltammetry, Mott–Schottky (MS) tests, electrochemical impedance spectroscopy (EIS), in-situ laser Raman spectroscopy, and electrochemical atomic force microscopy techniques (ECAFM). The results suggest that the single-component Cu 2 O layer exhibits p-type semiconductor properties. An interesting phenomenon was observed; the carrier concentration, and the diffusivity of the Cu + vacancies increased progressively as the oxide layer formation potential increased. The oxide layer was composed of granular cuprous oxide; relatively large Cu 2 O particles were formed on the surface under − 120 mV (Ag/AgCl) and − 60 mV (Ag/AgCl). At a film formation potential of − 120 mV (Ag/AgCl), the thickness of the oxide layer (Cu 2 O) was approximately 6.046 nm, while it was 0.5594 nm at 0 mV (Ag/AgCl). The Cu 2 O layer formed at a lower potential offers superior stability and protection. [ABSTRACT FROM AUTHOR]

The role of the mold in electrochemical migration (ECM) of printed circuit board (PCB) under DC bias was investigated using environment scanning electron microscope, 3D stereology microscopy, and scanning Kelvin probe. The mold under electrical bias can grow well and complete with the processes of growth, metabolism and proliferation. The mold can also promote metal ionization and localized corrosion and provide the ion source for ECM process. The cooperation of mold and DC bias promote ECM process on PCB and aggravate short circuit failure behavior. The proposed ECM mechanisms explain the ECM process of PCB under mold and DC bias environment. [ABSTRACT FROM AUTHOR]

In order to study the deformation and stress-strain relationship of FRP (fiber reinforced plastics) confined concrete under a long-term sustained loading, the model GL2000 and model Findley were selected firstly as concrete creep model and FRP creep model, respectively by analyzing 8616 data of concrete creep and 4320 data of concrete shrinkage. Then according to the conditions of static and geometry equilibrium, a method of long-term deformation was proposed. Moreover, an equation for calculating the ultimate compressive strength and strain of FRP confined concrete was suggested by considering the initial stress. Finally based on the axial-lateral strain relationship proposed by Teng and actively-confined concrete model proposed by Mander, an analysis-oriented stress-strain model was built by an incremental-iterative method. It is found that the predicting results of the long-term deformation method and the stressstrain model agree well with the test data. [ABSTRACT FROM AUTHOR]

Electroless nickel/immersion gold (ENIG)-plated printed circuit boards (PCBs) were exposed to typical atmospheric environments in China for prolonged periods to understand the mechanism of corrosion failure. Results showed that the corrosion products that covered PCB-ENIG played a protective role by filling, covering, and coating surface defects. Under Turpan atmospheric environment, the plating layer was prone to damage easily, resulting in loss of protective properties. The corrosion mechanism was mainly microporous corrosion, in which halo-shaped macropores with a raised nucleus in the center were formed. When electrical bias was applied, PCB-ENIG was prone to electrochemical migration (ECM) caused by galvanic effects in the form of localized corrosion. Both Ni and Cu elements were involved in the ECM process. The synergistic effect of contaminated medium and high humidity is the critical factor of the ECM-induced PCB-ENIG corrosion. [ABSTRACT FROM AUTHOR]

Submerged berms are an increasingly used coastal defense structure for beach nourishment because of their eco-friendly nature. A beach-nourishment project that included sand placement on the beach and in the nearshore area as a submerged berm was carried out in the winter of 2010 on West Beach in Qinhuangdao, China. West Beach is a low-energy beach characterized by small wave heights, a small tidal range, and low tidal-flow velocities. An analysis of the postnourishment beach profile evolution was conducted based on beach profile surveys from 2011 to 2014. The analysis showed that the most active parts of the profiles were the berm and the submerged berm, whereas the remaining parts of the profiles remained relatively stable. The cross-shore profiles of the submerged berm evolved significantly from roughly symmetrical shapes to asymmetrical shapes, which can be explained by applying the concept of equilibrium wave-energy dissipation per unit of water to a low-energy beach with a submerged berm. Empirical orthogonal function analysis was conducted on the beach profile surveys, which confirmed the features of the background-berms pattern gained from the evolution analysis. The first three eigenfunctions corresponded to the mean beach profile, the volume changes of the berm and the submerged berm, and the change in the submerged berm from roughly symmetrical to asymmetrical in shape, respectively. Finally, a new equilibrium beach profile (EBP) form was developed to represent low-energy sandy beaches with submerged berms. The findings in this paper contribute to the understanding of cross-shore beach morphodynamics and can provide a reference for beach nourishment under similar conditions. [ABSTRACT FROM AUTHOR]

The oil shale from open-pit oil shale mine of Fushun, Liaoning province was chosen as our study objective, the effect of the time and temperature on oil shale crack was studied. The results showed that with the temperature increasing, crack width, length and quantity increased. When temperature was greater than 300 °C, the length and quantity increased rapidly, so, the threshold temperature was 300 °C; with the heating time increasing, the crack width and quantity increased first, then decreased, while the length presented an increase. The crack quantity reached the maximum for heating 8 h and crack width reached the broadest at 6 h. So the optimum heating time is 6-8 h. [ABSTRACT FROM AUTHOR]

The corrosion behavior and electrochemical migration mechanism of a copper-clad plate (PCB-Cu) in a marine atmospheric environment with industrial pollution were studied in field exposure experiments. The results showed that corrosion was initiated from activity locations with low potential. With extended exposure time, the amount of corrosion products increased and gradually formed a double layer structure. The inner layer corrosion products were mainly Cu 2 O; the outer layer mainly included CuCO 3 ·Cu(OH) 2 , Cu(OH) 2 ·CuO·HCl, CuSO 4 ·3Cu(OH) 2 and CuSO 3 ·3Cu(OH) 2 . When a 12 V bias voltage was applied, an anomalous electrochemical migration (ECM) phenomenon was observed: a Cu dendrite was produced near the anode and migrated toward the cathode. Finally, ECM led to the bridge connection of the two metallization stripes and caused a short circuit in the PCB-Cu. [ABSTRACT FROM AUTHOR]

The ionization energies (IEs) of TiO and TiO2 and the 0 K bond dissociation energies (D0) and the heats of formation at 0 K (ΔH°f0) and 298 K (ΔH°f298) for TiO/TiO+ and TiO2/TiO2+ are predicted by the wave-function-based CCSDTQ/CBS approach. The CCSDTQ/CBS calculations involve the approximation to the complete basis set (CBS) limit at the coupled cluster level up to full quadruple excitations along with the zero-point vibrational energy (ZPVE), high-order correlation (HOC), core--valence (CV) electronic, spin--orbit (SO) coupling, and scalar relativistic (SR) effect corrections. The present calculations yield IE(TiO) = 6.815 eV and are in good agreement with the experimental IE value of 6.819 80 ± 0.000 10 eV determined in a two-color laser-pulsed field ionization-photoelectron (PFI-PE) study. The CCSDT and MRCI+Q methods give the best predictions to the harmonic frequencies: ωe (ωe+) = 1013 (1069) and 1027 (1059) cm-1 and the bond lengths re (re+) = 1.625 (1.587) and 1.621 (1.588) Å, for TiO (TiO+) compared with the experimental values. Two nearly degenerate, stable structures are found for TiO2 cation: TiO2+(C2v) structure has two equivalent TiO bonds, while the TiO2+(Cs) structure features a long and a short TiO bond. The IEs for the TiO2+(C2v)←TiO2 and TiO2+(Cs)←TiO2 ionization transitions are calculated to be 9.515 and 9.525 eV, respectively, giving the theoretical adiabatic IE value in good agreement with the experiment IE(TiO2) = 9.573 55 ± 0.000 15 eV obtained in the previous vacuum ultraviolet (VUV)--PFI-PE study of TiO2. The potential energy surface of TiO2+ along the normal vibrational coordinates of asymmetric stretching mode (ω3+) is nearly flat and exhibits a double-well potential with the well of TiO2+ (Cs) situated around the central well of TiO2+ (C2v). This makes the theoretical calculation of ω3+ infeasible. For the symmetric stretching (ω1+), the current theoretical predictions overestimate the experimental value of 829.1 ± 2.0 cm-1 by more than 100 cm-1. This work together with the previous experimental and theoretical investigations supports the conclusion that the CCSDTQ/CBS approach is capable of providing reliable IE and D0 predictions for TiO/TiO+ and TiO2/TiO2+ with error limits less than or equal to 60 meV. The CCSDTQ/CBS calculations give the predictions of D0(Ti+--O) -- D0(Ti--O) = 0.004 eV and D0(O--TiO) -- D0(O--TiO+) = 2.699 eV, which are also consistent with the respective experimental determination of 0.008 32 ± 0.000 10 and 2.753 75 ± 0.000 18 eV. [ABSTRACT FROM AUTHOR]

Background: Insulin resistance is a pathogenic factor for type II diabetes and has been associated with metabolic abnormalities and adverse clinical outcomes. The purpose of this study was to examine the relationship between insulin resistance and socio-demographics, adiposity and behavioral factors in the general, non-diabetic adult Canadian population. Methods: Data for 3515 non-diabetic adults aged 18 to 79 years from the Canadian Health Measures Survey (cycles 1 and 2, 2007-2011) were analyzed. Insulin resistance index was measured by the homeostasis model assessment of insulin resistance (HOMA-IR), and insulin resistance (IR) was defined as individuals in the highest quartile of the HOMA-IR index. Logistic regression models were used to examine the effect of demographics, lifestyle factors and adiposity measurements on HOMA-IR. Results: The risk of IR increased with age, particularly in men. Individuals had adjusted odds ratio (OR) (with corresponding 95 % confidence interval) of 5.97 (2.90-8.52) and 25.12 (15.20-41.51) associated with a body-massindex (BMI) between 25.0 and < 30.0, or ≥30.0, of 9.23 (6.52-13.07) with abdominal obesity (waist circumstance ≥102 cm for men and ≥ 88 cm for women), of 8.72 (6.13-12.39) with a high waist-to-height ratio (>0.57), and of 6. 30 (4.33-9.16) with a high waist-to-hip ratio (>0.90 for men and >0.85 for women). Physically inactive people and non-alcohol consumer also had a significantly higher odd of IR. Conclusions: This study found that men and older, obese and physically inactive people were at increased risk for IR. Adiposity indices including BMI, waist circumstance, waist-to-height ratio and waist-to-hip ratio were highly associated with IR with similar magnitude of association. [ABSTRACT FROM AUTHOR]

For the usage of dialkyl phosphate as a gelatinizer in oil-based fracturing fluids, two methods of preparation are involved. The improved ethyl phosphate method is used to control one of the ester chains by using a single alcohol substitute for mixed alcohols. A new method for polyphosphates is used to control both the ester chains. Different kinds of alcohols are used as the raw materials in a 3×3 orthogonal experiment (ratio of reactants, reaction temperature and reaction time) to obtain the optimum reaction conditions. Furthermore, 14 kinds of gelatinizers are produced in these experiments. The viscosity of the products is used as an evaluation index. The results based on these two methods showed that there is a positive correlation between the length of the dialkyl phosphate ester chain and the viscosity of the fracturing fluid with a certain number of carbon atoms. In other words, the viscosity of the fracturing fluid increased with an increasing length of the ester chain length. Then the growth slowed down. The viscosity of the products that were produced by the polyphosphate method was visibly improved by 7.72-45.35% of the level of the other. За синтезу диалкил-фосфата, који се користе као угушћивачи течности на бази уља за хидраулично разбијање ("fracking"), примењена су два поступка. Први, побољшани етил-фосфатни поступак - омогућава контролу само једног естарског ланаца, заменом једне ОH групе у моноетил-фосфату, док други, нови полифосфатни поступак, омогу- ћава контролу оба естарска ланца. Различите врсте алкохола су се користиле као сиро-вине у 3×3 ортогоналном дизајну експеримента (однос реактаната, температура и време одигравања реакције) да би се установили оптимални услови извођења реакције. Као резултат ових експеримената, добијено је 14 различитих врста угушћивача, који су поре- ђени на основу вискозности. Показано је да угушћивачи синтетисани на оба начина испољавају исти тренд, тј. да дужина ланаца диалкил-фосфатних естара утиче на пораст вискозности течности за хидрулично разбијање до одређеног броја угљеникових атома. Другим речима, вискозност флуида се повећава са порастом дужине естарских ланаца и достиже максимум на C13, а након тога опада. Вискозност производа на бази диалкил- -фосфатних естара добијених полифосфатним поступком је била 7,7-45,3% већа у односу на аналогне производе добијене побољшаним етил-фосфатним поступком. [ABSTRACT FROM AUTHOR]

[Display omitted] Monocyte chemotactic protein-1 (MCP-1) is known to be able to facilitate vascular endothelial growth factor (VEGF) gene expression, hence promoting vascular hyperpermeability and neovascularization. We show here that a microRNA molecule, miR-374b-5p can target the 3′-untranslated region of the VEGF mRNA, thus preventing VEGF production. Additionally, MCP-1 promotes the acetylation of transcription factor stat3 at Lys685, which facilitates the formation of an ac-stat3-DNA methyltransferase-histone methyltransferase complex (ac-stat3/DNMT1/EZH2) that binds to the promoter of the miR-374b-5p gene. This results in diminished miR-374b-5p expression and enhanced VEGF production. Moreover, treatment of appropriate animal models either with a miR-374b-5p mimicry or with inhibitors of either stat3 acetylation, DNMT1, or EZH2, leads to marked inhibition of MCP-1-promoted neovascularization and tumor growth. These findings indicate that MCP-1 facilitated inhibition of miR-374b-5p gene expression leads to the removal of a block of VEGF mRNA translation by miR-374b-5p. This mechanism could be of importance in the modulation of inflammatory conditions. [ABSTRACT FROM AUTHOR]

To improve the precision of reliability analysis on turbine blades, the fuzzy response surface method of reliability analysis is proposed by considering the fuzziness of the input variables and the vagueness of the limit state variables. Initially, the fuzzy basic variables were converted into equivalent random variables according to the method of equivalent transformation. Additionally, the mathematic model of the fuzzy response surface for structural reliability analysis was established, based on the quadratic polynomial response surface function. The mean value and variance of the blade stress and radial deformation were obtained by using the Monte-Carlo method based on generous linkage sampling to the model. Finally, the probability of failure and fuzzy random reliability index were calculated based on the probability integral method. Results indicate that the reliability probability of the blade is 97.665%, when the allowable stress and deformation are 390 MPa and 0.195 mm, respectively. It is demonstrated that with an increase of the fuzzy coefficient, the blade reliability index decreases; thus, the random reliability of the blade is slightly higher than the fuzzy reliability. [ABSTRACT FROM AUTHOR]

A research project for senior undergraduates of chemistry has been developed to introduce syntheses of a series of monodispersed semiconductor PbS quantum dots (QDs) and their characterization methodologies. In this paper, we report the preparation of monodispersed semiconductor PbS QDs with sizes smaller than the exciton Bohr radius using a simple, one-step process, and the characterization of the QDs using a range of instruments, including Fourier-transform infrared spectroscopy, transmission electron microscopy (TEM), high-resolution TEM (HRTEM), and energy-dispersive X-ray spectroscopy. Our synthesis approach involves dissolving powdered sulfur (as the S precursor) in 1-tetradecene and adding PbCl2 as the Pb precursor to the suspension as well as oleylamine as a capping ligand. The PbS QD project represents, we believe, an almost ideal opportunity to provide exposure of undergraduate students to nanotechnology research via syntheses and characterization of semiconductor nanoparticles. [ABSTRACT FROM AUTHOR]

Quantum-dot molecules were constructed on a semiconductor surface using atom manipulation by scanning tunneling microscopy (STM) at 5 K. The molecules consist of several coupled quantum dots, each of which comprises a chain of charged adatoms that electrostatically confines intrinsic surface-state electrons. The coupling takes place across tunnel barriers created reversibly using the STM tip. These barriers have an invariant, reproducible atomic structure and can be positioned--and repeatedly repositioned--to create a series of reconfigurable quantum-dot molecules with atomic precision. [ABSTRACT FROM AUTHOR]

In this work, crude polysaccharide extracts were obtained from mycelia of the edible fungus Ganoderma capense (Lloyd) Teng. After removal of proteins by the Sevage method, fractionation and purification by anion-exchange and gel-permeation chromatography, a polysaccharide (GCPB-3) was isolated. The relative molecular weight of GCPB-3 was 124 kDa determined by high performance gel permeation chromatography (HPGPC). The homogeneous polysaccharide was composed of d -xylose and l -arabinose in the ratio of 1:1, and showed a specific optical rotation of [ α ] D 25 = +145°(c 1.0, H 2 O). Its structural features were determined by monosaccharide analysis, partial acid hydrolysis, methylation analysis, periodic acid oxidation, gas chromatography-mass spectrometry (GC-MS), Fourier transform-infrared spectroscopy (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy ( 1 H, 13 C, HMQC and HMBC). The results characterized GCPB-3 as a heteropolysaccharide with backbone consisting of β- l -Ara p and β- d -Xyl p , linked with 1→4 sugar bonds. Interestingly, GCPB-3 showed some DPPH•- and hydroxy-radical scavenging activities. [ABSTRACT FROM AUTHOR]

The electronic structure of CaO films of 10-60 monolayer thickness grown on Mo(001) has been investigated with synchrotron-mediated x-ray photoelectron spectroscopy (XPS) and scanning tunneling microscopy (STM). Upon annealing or reducing the thickness of the film, a rigid shift of the CaO bands to lower energy is revealed. This evolution is explained with a temperature-induced diffusion of Mo ions from the metal substrate to the oxide and their accumulation in the interface region of the film. The Mo substitutes divalent Ca species in the rocksalt lattice and is able to release electrons to the system. The subsequent changes in the Mo oxidation state have been followed with high-resolution XPS measurements. While near-interface Mo transfers extra electrons back to the substrate, generating an interface dipole that gives rise to the observed band shift, near-surface species are able to exchange electrons with adsorbates bound to the oxide surface. For example, exposure of O2 results in the formation of superoxo species on the oxide surface, as revealed from STM measurements. Mo interdiffusion is therefore responsible for the pronounced donor character of the initially inert oxide, and largely modifies its adsorption and reactivity behavior. [ABSTRACT FROM AUTHOR]

The oxidation of various alkanes catalyzed by [MnV(N)(CN)4]2- using various terminal oxidants at room temperature has been investigated. Excellent yields of alcohols and ketones (>95%) are obtained using H2O2 as oxidant and CF3CH2OH as solvent. Good yields (>80%) are also obtained using (NH4)2[Ce(NO3)6] in CF3CH2OH/H2O. Kinetic isotope effects (KIEs) are determined by using an equimolar mixture of cyclohexane (c-C6H12) and cyclohexane-d12 (c-C6D12) as substrate. The KIEs are 3.1 ± 0.3 and 3.6 ±0.2 for oxidation by H2O2 and Ce(IV), respectively. On the other hand, the rate constants for the formation of products using c-C6H12 or c-C6D12 as single substrate are the same. These results are consistent with initial rate-limiting formation of an active intermediate between [Mn(N)(CN)4]2- and H2O2 or CeIV, followed by H-atom abstraction from cyclohexane by the active intermediate. When PhCH2C(CH3)2OOH (MPPH) is used as oxidant for the oxidation of c-C6H12, the major products are c-C6H11OH, c-C6H10O, and PhCH2C(CH3)2OH (MPPOH), suggesting heterolytic cleavage of MPPH to generate a Mn-O intermediate. In the reaction of H2O2 with [Mn(N)(CN)4]2- in CF3CH2OH, a peak at m/z 628.1 was observed in the electrospray ionization mass spectrometry, which is assigned to the solvated manganese nitrido oxo species, (PPh4)[Mn(N)(O)(CN)4]-∙CF3CH2OH. On the basis of the experimental results the proposed mechanism for catalytic alkane oxidation by [MnV(N)(CN)4]2-/ROOH involves initial rate-limiting O-atom transfer from ROOH to [Mn(N)(CN)4]2- to generate a manganese(VII) nitrido oxo active species, [MnVII(N)(O)(CN)4]2-, which then oxidizes alkanes (R'H) via a H-atom abstraction/O-rebound mechanism. The proposed mechanism is also supported by density functional theory calculations. [ABSTRACT FROM AUTHOR]

Adipose tissue inflammation is now considered to be a key process underlying metabolic diseases in obese individuals. However, it remains unclear how adipose inflammation is initiated and maintained or the mechanism by which inflammation develops. We found that microRNA-802 (Mir802) expression in adipose tissue is progressively increased with the development of dietary obesity in obese mice and humans. The increasing trend of Mir802 preceded the accumulation of macrophages. Adipose tissue-specific knockout of Mir802 lowered macrophage infiltration and ameliorated systemic insulin resistance. Conversely, the specific overexpression of Mir802 in adipose tissue aggravated adipose inflammation in mice fed a high-fat diet. Mechanistically, Mir802 activates noncanonical and canonical NF-κB pathways by targeting its negative regulator, TRAF3. Next, NF-κB orchestrated the expression of chemokines and SREBP1, leading to strong recruitment and M1-like polarization of macrophages. Our findings indicate that Mir802 endows adipose tissue with the ability to recruit and polarize macrophages, which underscores Mir802 as an innovative and attractive candidate for miRNA-based immune therapy for adipose inflammation. [ABSTRACT FROM AUTHOR]

We present a versatile nickel-electrocatalytic deaminative cross-coupling platform for the efficient construction of C(sp3)-C(sp3) and C(sp3)-C(sp2) bonds from readily available alkyl bistriflimides. This methodology involves the assembly of two leaving groups on alkyl amines to form alkyl bistriflimides, followed by their effective coupling with a wide range of alkyl halides, alkyl pseudohalides, aryl halides, and alkenyl halides under electrochemical reductive conditions. Moreover, the successful application of electrochemical reductive relay cross-coupling and transition metal-free cross-electrophile coupling further demonstrates the versatility of alkyl bistriflimides as valuable building blocks in organic synthesis. Combined control experiments and density functional theory calculations provide insights into the reaction pathway and the crucial role of iodide in the catalytic process. [ABSTRACT FROM AUTHOR]