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To overcome two obstacles in graphene functionalization—the random distribution of functional groups and substantial lattice defects, in this contribution, we rationally bypass the universal yet de...

Dry polymer brushes have attracted great attention because of their potential utility in regulating interface properties. However, it is still unknown whether dry polymer brushes will exhibit degrafting behavior as a result of thermal annealing. Herein, a study of the conformational entropy effect on thermal degrafting of dry polystyrene (PS) brushes is presented. For PS brushes with an initial grafting density (σ

Intelligent mines require much more mental effort from visual display terminal (VDT) operators. Long periods of mental effort can easily result in operator fatigue, which further increases the possibility of operation error. Therefore, research into how brain fatigue affects the sustained attention of VDT operators in intelligent mines is important. The research methods were as follows: (1) Recruit 17 intelligent mine VDT operators as subjects. Select objective physiological indicators, such as reaction time, error rate, task duration, flicker fusion frequency, heart rate, electrodermal activity, and blink frequency, and combine these with the subjective Karolinska Sleepiness Scale to build a comprehensive brain fatigue evaluation system. (2) According to the fatigue-inducing experiment requirements, subjects are required to carry out mathematical operations in accordance with the rules during the presentation time, determine whether the results of the operations fall within the [7, 13] interval, and continue for 120 min to induce brain fatigue. (3) Perform the standard stimulus button response experiment of the sustained attention to response task, before and after brain fatigue, and compare each result. The results show that: (1) When the standard stimulus appeared in the EEG experiment, the amplitude of the early N100 component before and after brain fatigue was significantly different. When the bias stimulus appeared, the average amplitudes of the P200 component and the late positive component, before and after brain fatigue, were significantly different, suggesting that the brain fatigue of VDT workers in coal mines would reduce sustained attention; (2) After the 120 min of the continuous operation task, the subjects showed obvious brain fatigue. The objective brain fatigue was followed by an increase in reaction time, an increase in error rate, a decrease in flicker fusion frequency, an increase in heart rate, an increase in electrodermal current, an increase in the number of blinks, and a larger pupil diameter, and both the subjective and objective data indicated more significant changes in the subjects’ brain fatigue at the 45th and 90th min. The results of the study could provide insight into the reduction in operational efficiency and safety of VDT operators in intelligent mines due to brain fatigue and further enrich the research in the area of brain fatigue in VDT operations.

Uncontrolled hemorrhage caused by trauma to internal organs or major arteries poses critical threats to lives. However, rapid hemostasis followed by tissue repair remains an intractable challenge in surgery owing to the lack of ideal internal-use adhesives that can achieve fast and robust wet adhesion and accelerate wound healing. Herein, we develop a robust hemostatic bioadhesive (CAGA) from novel highly-branched aminoethyl gelatin with end-grafted abundant catechol (Gel-AE-Ca). The unique chemical structure of Gel-AE-Ca makes CAGA capable of gelling on wet tissues via synergetic cross-linking of catechol-Fe

Capsaicin has been extensively studied for its excellent antifouling activity and very low environmental toxicity. However, mixing natural capsaicin with coatings can cause rapid capsaicin leakage, severely shortening its antifouling cycle. In this study, we describe the preparation and performance of a new capsaicin-modified marine antifouling organofluorosilicone, which is based on silicone and fluorine acrylate monomers covalently bound to an organic antimicrobial monomer, HMBA (N-(4-hydroxy-3-methoxybenzyl)-acrylamide) on a polymer network. The chemical grafting of HMBA into the polymer has improved the problem of short antifouling life of the coating due to antifouling agent leakage and the environmental pollution caused by the leakage. The study focused on the synthesis of pristine acrylate monomers with organic bioactive groups prepared from vanillin amine salts and their co-polymerization in the presence of distal acrylate oligomers. The resulting cross-linked films were characterized using infrared spectroscopy, contact angle, and adhesion analyses. The results indicate that the materials had good adhesion, low surface energy, and were resistant to prolonged immersion in water. The polyacrylate coating synthesized from acrylate exhibited antibacterial and anti-algae activity. Biological tests on the marine microorganisms, Pseudomonas species, Shewanella species, and Navicula incerta, revealed a 97%, 98%, and 99% reduction compared to the blank control group, respectively, indicating that the coating has strong anti-adhesive ability. This work is expected to develop a promising material for marine antifouling.

Shared manufacturing provides a new path for the transformation and development of the manufacturing industry, but challenges such as low quality and poor positivity for quality improvement limit the positive role of shared manufacturing. Considering the influences of heterogeneous emotions of subjects on quality decision making, the theory of rank-dependent expected utility (RDEU) and evolutionary game theory were integrated to establish an evolutionary game model of shared manufacturing quality innovation synergy with multi-agent participation and analyze how sentiment affects motivation for quality improvement. The study showed that: (1) emotions, an irrational factor, can significantly change the stable state of the evolution of the shared manufacturing quality innovation synergetic system by influencing the decision-making behavior of decision makers; (2) in terms of the specific microscopic influence mechanism, rationality is the key to ensuring that the behavioral decisions of decision makers do not enshrine large systemic deviations. (3) In terms of the mechanism of heterogeneous emotions, when one party is optimistic, the deepening of the other party’s pessimism tends to bring positive effects; when one party is pessimistic, the deepening of the other party’s optimism tends to bring negative effects. The main management insights are as follows: (1) correctly recognizing and treating heterogeneous emotions of decision makers and regulating the formation and role of heterogeneous emotions of decision makers; (2) appropriately creating an atmosphere of pessimistic emotions, and guiding shared manufacturing to pay attention to manufacturing quality innovation synergy; (3) appropriately releasing favorable information about quality innovation synergy, and continuously promoting high-quality development of shared manufacturing. This study broadens the path of quality improvement in shared manufacturing and the scope of application of emotion theory in a certain sense.

The interfacial orientation of aromatic groups plays a crucial role in determining the properties of graphene-based aromatic polymer nanocomposites. Here, the interfacial orientation of the polystyrene (PS) phenyl groups in contact with graphene is revealed by sum frequency generation (SFG) vibrational spectroscopy. The SFG spectra showed that the orientation of the phenyl groups is closely related to the interfacial concentration as the chains reach the quasi-equilibrium state. The phenyl groups remain in a relatively unrestricted state at a low concentration of the PS phenyl groups, and they prefer to recline to more favorably interact with graphene via a face-to-face configuration. Densely stacked phenyl groups are too crowded to form multilayer face-to-face interactions with graphene, and they prefer to remain upright, while π-π interactions are formed among the phenyl groups themselves in addition to the edge-to-face interactions to maximize the bonding energy of the π-π interactions. This is enthalpically favorable and driven mainly by the π-π interactions. This work provides important knowledge for the design and optimization of functional graphene-based aromatic polymer nanocomposites.

Objective: Small-vessel occlusions are the most common causes of mild strokes and, in China, account for approximately 27.3% of ischemic stroke cases. However, the factors associated with short- an...

It is highly urgent to develop synthetic strategies to make new category of stable luminescent radicals with desired emission wavelength. In this study, we have isolated two dioxoborocyclic radicals ( 3 and 4 ) by a direct sy nthetic rou te. They were charac terized by UV, EPR spectroscopy and SQUID measurements. Their structures were obtained by single crystal X ray diffraction. Both radicals produce blue photoluminescence (458 nm for 3 and 478 nm for 4 ) by radiative decay from higher excited states (D2/D3) to the ground state (D0) based on theoretical calculation, breaking Kasha rule. The work records a new kind of radical emitters and the first stable radicals with blue emission bands.

The thickness effect on the relaxation behavior and chain entanglements was investigated for thin polystyrene films. By following the time evolution of the wetting ridge at the surface induced by a...

Thermally sensitive polymers have attracted tremendous interest in the design of stimulus-responsive surfactants. In this article, poly(propylene oxide)-b-poly(N-isopropylacrylamide) (PPO-b-PNIPAm) with different block lengths of PNIPAm was synthesized through atom transfer radical polymerization (ATRP). Different from commercial Pluronic surfactants, four distinct sections appeared in the decrease of surface tension with concentration. First, with increasing concentration, the amount of adsorbed polymers increased and the surface tension decreased sharply until a plateau was reached, which was caused by the rearrangement of methyl groups. The increasing adsorbed amount of PPO-b-PNIPAm resulted in the rearrangement of isopropyl groups, which changed from a lying down or horizontal conformation to a standing up or vertical conformation. This behavior led to the decrease in surface tension in part III until the critical micelle concentration (CMC) was reached. The surface tension of PPO-b-PNIPAm was thermally responsive. Except for the hysteresis observed in the first cycle, the surface tension was reversible during the heating-and-cooling cycles. At low concentrations, the low surface tension at higher temperatures was mainly caused by the increasing adsorption amount and ordered arrangement of methyl groups, while the standing up conformation of isopropyl groups at higher concentrations resulted in the low surface tension observed at high temperatures.

Inaccessible home environments that create barriers to the enjoyment and the approachability of the living space impact some U.S. Veterans. Injuries acquired while serving in the military or develo...

An environmentally friendly chelating agent, tetrasodium iminodisuccinate (IDS), was investigated as an inhibitor in the simulated concrete pore solution on Q235 carbon steel by using Tafel polarization (TF), electrochemical impedance spectroscopy (EIS) and surface morphology tests. The EIS and TF results indicate that the IDS is a mixed type of inhibitor and exhibits excellent protection efficiency (97.54%) at 200 mg/L. Furthermore, based on the Langmuir adsorption isotherm, IDS protects carbon steel through physical and chemical adsorption. Besides, density functional theory (DFT) and molecular dynamics (MD) simulations are applied to explore the inhibition mechanism to support the experimental data, indicating that IDS can be used as a new green corrosion inhibitor.

The concept of free volume underpins the variations in polymer dynamics. Annihilation of free-volume holes through diffusion to surfaces has been proposed to determine the vitrification of the confined polymers. In this work, we assessed the hole diffusion dynamics in glassy thin poly (ethylene terephthalate) films with various thicknesses using a strategy based on covering the film surface with crystals of different sizes, which allows for changing the hole diffusion efficiency, thus tuning the glass transition temperature of the thin film (Tgfilm). The apparent activation energy for hole diffusion (Ea,hole) in the thin films was elucidated by modeling the correlation between Tgfilm and surface coverage of crystals using the free-volume hole diffusion model. Our results demonstrated a trend of linear decrease in Ea,hole with the increasing inverse film thickness (h–1), suggesting that the presence of a free surface with faster dynamics promotes hole diffusion in thin films. This finding demonstrates that the free volume release in thin films and thus the confined polymer dynamics can be modulated by changing the free surface properties of the films., B.Z. acknowledges financial support from Natural Science Foundation of China (Grant nos. 21973083) and Projects of International Cooperation and Exchanges NSFC (Grant nos. 22011530456). D.C. acknowledges financial support from the project PGC2018-094548-B-I00 (MICINN-Spain and FEDER-UE) and the project IT-1175-19 (Basque Government).

The dynamics of different blocks in block copolymers are expected to affect the other blocks due to compositional heterogeneity, thus influencing their bulk structure and performance. It is signifi...

A PtZn/0.02TS-170 catalyst with very high activity, selectivity, and catalytic durability for propane dehydrogenation is reported in this paper. It was found that the excellent properties of the catalyst originate from the strong interaction of the Ti existing in the zeolite framework with Zn and Pt. The Ti not only remarkably increases the Pt dispersion and thereby enhances the initial activity of the catalyst, but also significantly modifies the electronic density of Pt together with the Zn and therefore increases the durability of the catalyst. The crucial functions of the Ti in constructing the structure and for modifying the reaction were evidenced by the CO adsorption capacity, CO adsorption IR spectroscopy and C3H6-TPD of the related catalysts. Thanks to the interaction of the Ti with Zn and Pt, the PtZn/0.02TS-170 catalyst exhibited a very high initial specific rate of 58.09 molC3H6 gPt−1 h−1 and a quite low deactivation constant of 0.0158 h−1 in the 96.8 h time on stream at 600 °C.

One-electron reduction of 2,7-tBu2-pyrene-4,5,9,10-tetraone (1) with potassium afforded two monoradicals 1K(cryp) and 1K(18c6), a radical tetramer [1K(15c5)]4 and a radical polymer (1K)2n. Using 1K(cryp) and 1K(18c6), we demonstrated large spin density modulation of an organic radical anion in the solid state by electrostatic attraction, without alternation of the molecular skeletons.

The catalytic decomposition of N2O was investigated over Mg–Co composite oxide catalysts. It was found that the activities of the catalysts could be significantly enhanced by hydrothermally treating the precipitate coming from the co-deposition of Mg2+ and Co2+ using Na2CO3 as a precipitant. By correlating the physical and chemical characterization results with the activities for the catalyst samples prepared with and without the hydrothermal treatment, a mechanism accounting for the increased activity due to the hydrothermal treatment was discussed. It was demonstrated that the substitution extent of CoT (tetrahedral cobalt of the spinel) by Mg is the key factor that determines the activity of the composite catalysts, and hydrothermal treatment is highly favorable for the ions' replacement during the preparation procedure. The formation of the coordinatively unsaturated octahedral cobalt (CoO) on the spinel surface is therefore remarkably accelerated under the reaction conditions, since the CoO–O bond is significantly weakened by the substitution, which explains why the hydrothermal treatment gave the resulting catalyst with a much higher activity compared with that without the treatment.

Anatase-free titanium silicalite-1 (TS-1) zeolite with a high framework titanium content is highly required for catalysing selective oxidation reactions, however, its synthesis generally suffers from issues relating to cost, efficiency, and environmental friendliness. Herein, a new protocol was proposed for synthesizing a zeolite with the necessary characteristics. It involved dissolving large amounts of S-1 zeolite at 80 °C to prepare liquid seeds, which avoided anatase TiO2 impurity formation and accelerated the incorporation of titanium into the zeolite framework, and using fumed silica as a silicon source in the zeolite to decrease the amount of wastewater discharge. By using this protocol, uniform anatase-free nanosized hierarchical TS-1 zeolite with a Si/Ti ratio of 41, with very high activity for the cyclohexanone ammoximation reaction, was obtained. ESI-MS and DLS analyses indicate that primary silicon species with four- or five-membered rings in the liquid seeds significantly accelerated the crystallization of TS-1 zeolite and the incorporation of titanium into the zeolite framework.

Two-electron oxidation of five aniline-based compounds 4,4′′-p/m-terphenyldiamines afforded a class of terphenyldiamine dications 12+–52+. Their electronic structures were systematically investigated by theoretical calculations and various experiments, including single-crystal X-ray diffraction, UV/Vis absorption spectroscopy, EPR spectroscopy and SQUID measurements. p-Terphenyldiamine dications 12+–32+ are open-shell singlets in the ground state with large singlet–triplet energy gaps. The inherent instability of dication 42+ precludes the determination of its ground state, whereas the observed linear Curie plot for m-terphenyldiamine dication 52+ indicates that its ground state is triplet. The calculated singlet–triplet energy gap (ΔEOS–T) value is 1.27 kcal mol−1 for 42+ and 1.10 kcal mol−1 for 52+. This work provides the first examples of isolable aniline-based diradical dications.

The film thickness and substrate interface are the two most common parameters to tune the dynamics of supported thin films. Here, we investigated the glass transition temperature (Tg) and thermal e...

The study aimed to explore the effects of atractylon on the proliferation and apoptosis of intestinal cancer cells through the phosphatidylinositol 3-hydroxy kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway. The intestinal cancer HT29 cell lines were cultured in vitro, and atractylon at different concentrations (15 and 30 mg/mL) was added. Then cell proliferative activity was detected via cell counting kit-8 (CCK8) assay, and the proportion of positive cells was determined using EdU staining. The content of interferon-γ (INF-γ), tumor necrosis factor-α (TNF-α) and matrix metalloproteinase-9 (MMP-9) was detected via enzyme-linked immunosorbent assay (ELISA), and the apoptosis of HT29 cells was detected through terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining. Moreover, reverse transcription-polymerase chain reaction (RT-PCR) was performed to determine the messenger ribonucleic acid (mRNA) levels of proliferation, apoptosis and PI3K/AKT/mTOR signaling pathway-related genes, and Western blotting was used to analyze the expression of the PI3K/AKT/mTOR signaling pathway. The cell growth status was poorer with a lower density in the 15 mg/mL atractylon group and basically normal morphological structure in the 30 mg/mL atractylon group. The number of cells significantly declined and the proliferative activity was also significantly weakened in the 30 mg/mL atractylon group. There were obviously more apoptotic cells in the 30 mg/mL atractylon group. Besides, INF-γ, TNF-α and MMP-9 were all evidently decreased in the 30 mg/mL atractylon group. Expressions of B-cell lymphoma-2 (Bcl-2), PI3K, AKT and mTOR obviously declined in the 30 mg/mL atractylon group, and they were raised in the NC group, while the expression of Caspase3 showed the opposite trends. Atractylon at an appropriate concentration can inhibit the proliferation and promote the apoptosis of intestinal cancer cells by suppressing the PI3K/AKT/mTOR signaling pathway, which can be used to treat colorectal cancer and other related diseases.

Due to the importance of the interface in the segmental dynamics of supported macromolecule ultrathin films, the glass transition temperature (

Coal mine accidents seriously affect people’s safety and social development, and intelligent mines have improved the production safety environment. However, safety management and miners’ work in intelligent mines face new changes and higher requirements, and the safety situation remains challenging. Therefore, exploring the key influencing factors of miners’ unsafe behaviors in intelligent mines is important. Our work focuses on (1) investigating the relationship and hierarchy of 20 factors, (2) using fuzzy theory to improve the decision-making trial and evaluation laboratory (DEMATEL) method and introducing the maximum mean de-entropy (MMDE) method to determine the unique threshold scientifically, and (3) developing a novel multi-criteria decision-making (MCDM) model to provide theoretical basis and methods for managers. The main conclusions are as follows: (1) the influence degree of government regulation, leadership attention, safety input level, safety system standardization, and dynamic supervision intensity exert the most significant influence on the others; (2) the causality of government regulation, which is the deep factor, is the highest, and self-efficacy displays the smallest causality, and it is the most sensitive compared to various other factors; (3) knowledge accumulation ability, man–machine compatibility, emergency management capability, and organizational safety culture has the highest centrality among the individual factors, device factors, management factors, and environmental factors, respectively. Thus, corresponding management measures are proposed to improve coal mine safety and miners’ occupational health.

Two radical cations of bis-BN-based analogues of Thiele's hydrocarbons were facilely synthesized, fully characterized, and theoretically investigated. One-electron oxidation leads to the reduced bond length alternation and NICS values of the central C

The polymorphism of methylenetetrahydrofolate reductase (MTHFR) gene C677T has been linked to H-type hypertension. But the conclusion remained controversial. To elucidate this issue, we performed a comprehensive meta-analysis to analyze the MTHFR C677T polymorphism and H-type hypertension.The English and Chinese databases were systematically searched to identify relevant studies until November 2020. RevMan 5.3 and Stata 12.0 software were used for meta-analysis. The odds ratio (ORs) and 95% confidence intervals (95% CIs) were used to assess the relationship between the MTHFR C677T polymorphism and H-type hypertension.A total of 14 studies involving 1769 cases and 1443 controls were included. The meta-analysis results showed the association between MTHFR C677T polymorphism and H-type hypertension with the homozygous codominant model (OR = 3.30, 95% CI = 1.94-5.60), heterozygous codominant model (OR = 2.34, 95% CI = 1.53-3.58), dominant model (OR = 1.79, 95% CI = 1.33-2.41), recessive model (OR = 2.70, 95% CI = 1.73-4.21),and the allelic model (OR = 1.82, 95% CI = 1.41-2.35). All p-values were less than 0.05. Therefore, MTHFR C677T polymorphism has a positive correlation with the risk of H-type hypertension. Among them, TT mutation has the greatest impact on the activity of this enzyme, which causes Hcy to rise and leads to H-type hypertension.In summary, our results provide sufficient data to support the hypothesis that the MTHFR C677T polymorphism is related to H-type hypertension susceptibility.

The behaviors of urban residents in terms of waste separation at source are crucial to achieve the reduction and recycling of waste in urban governance. In this study, the data were collected from 1008 respondents in Shaanxi province, the host of China’s 14th National Games; theoretical and empirical analyses were conducted to determine the factors influencing waste separation behaviors, and specific policy suggestions are proposed. The results show that the waste separation behaviors of urban residents are positively influenced by their cognition of waste pollution, ecological values, sense of social responsibility, perceived knowledge, and perceived utilities of waste separation. Moreover, the residents’ waste separation intentions partially mediate the relationships between their cognition of waste pollution, ecological values, perceived utilities, and waste separation behaviors, which almost totally mediate the relationship between their sense of social responsibility and waste separation behaviors. In addition, it was shown that the cost of waste separation can weaken the effect of waste separation intention on behavior, while waste separation facilities, social norms, and the publicity for China’s 14th National Games have the opposite effect. Finally, policy suggestions are proposed to encourage urban residents to adopt waste separation behaviors, contributing to transforming Shaanxi into a zero-waste province.

Aim. We aimed to explore the effects of Bupleuri Radix (BR) on the recurrence of resected colonic polyp (CP) by measuring angiogenin-2-induced protein kinase B (Ang PKB)/Akt signaling. Method. The main ingredients of BR were extracted by using ethanol and measured by HPLC. One hundred twenty patients with CP >10 mm who underwent resected surgery were randomly allocated to an aspirin (AG) or a BR medicine (BG) group. The allocation ratio was 1 : 1 and the intervention duration was one year. The recurrence rate of resected CP was investigated and the plasma levels of Ang PKB/Akt and inflammatory cytokines were measured using ELISA kits. After one-year surgery, side effects were recorded. The relationship between the serum levels of the main compounds of BR and plasma levels of Ang PKB/Akt was analyzed. Results. The main ingredients of CP are paeoniflorin, baicalin, saikosaponin A, and bupleurum saponin B2. Recurrence of resected CP was found in 17 patients from the AG group and eight patients from the BG group after one-year follow-up p < 0.05 . The levels of angiogenin-2 II and PKB/Akt in the AG group were higher than those in the BG group p < 0.05 . Meanwhile, BR treatment reduced the plasma levels of TNF-α, IL-1β, and IL-6, and increased the level of IL-10 p < 0.05 . Inflammatory cytokines are important factors that affect the recurrence of resected CP. Serum paeoniflorin, baicalin, saikosaponin A, and bupleurum saponin B2 in BR had a strong negative relationship with the plasma levels of Ang PKB/Akt. Conclusion. BR significantly reduces the recurrence risk of resected CP by affecting Ang PKB/Akt signaling.

The thickness dependent chain mobility in polymer films influenced by the interfacial effect was investigated by the cold crystallization behavior of thin poly(ethylene terephthalate) (PET) films c...

We show that the thickness, h0, dependence of the effective viscosity, ηeff(h0), of unentangled random copolymer films of styrene (St) and 4-methoxystyrene (MeOS) supported by silica (SiOx) can be ...

Because of the wide adaptability to samples in various states, UV–vis diffuse reflectance spectroscopy has attracted increasing attention. In the present work, it was firstly used to analyze lignocellulosic biomass material and develop the possible use for rapid detection. Through the analysis of the spectra, it was observed that the extremely pure microcrystalline cellulose, filter paper and purchased xylan have almost no absorption, whereas the chemical pulps, dissolving pulps and extracted hemicellulose with residual trace impurities show a weak absorption in the range from 200 nm to 400 nm. The prominent sensitivity to the trace impurities, such as residual lignin, makes the UV–vis diffuse reflectance spectroscopy a potential tool for the rapid detection of the purity of cellulose and hemicellulose. As for lignin, the spectrum is characterized by a broader strong absorption at 250–280 nm and 280–350 nm, of which the latter is similar to UV absorption spectra. In addition, UV–vis diffuse reflectance spectroscopy can be potentially used in monitoring lignin-like substance formation in the biomass engineering.

The thickness of the surface layer on both poly(methyl methacrylate) (PMMA) and polystyrene (PS) films was investigated by monitoring the surface reorganization of fluorinated tracer-labeled PMMA a...

One- and two-electron oxidation of a digallene stabilized by an N-heterocyclic carbene afforded the first stable gallium-based radical cation and dication salts, respectively. Structural analysis and theoretical calculations reveal that the oxidation occurs at the Ga=Ga double bond, leading to removal of π electrons of the double bond and a decrease of the bond order. The spin density of the radical cation mainly locates at the two gallium centers as demonstrated by EPR spectroscopy and theoretical calculations. Moreover, the reactivity of the radical cation salt toward nBu3 SnH and cyclo-S8 was studied; a digallium-hydride cation salt containing a Ga-Ga single bond and a gallium sulfide cluster bearing an unprecedented ladder-like Ga4 S4 core structure were obtained, respectively.

The one- and two-electron oxidation reactions of tetrathiolated di-tert-butylpyrene compound 1 with NO[Al(ORF)4] (ORF = OC(CF3)3) resulted in radical cation salt 1•+[Al(ORF)4]- and diradical dication salt 12+••·2[Al(ORF)4]-, respectively. Both salts were isolated as stable crystals and investigated by single-crystal X-ray diffraction, EPR spectroscopy, SQUID measurements, and UV-vis spectroscopy. The electron spin density is delocalized on one single sulfur-doped ring in 1•+ and on both sulfur-doped rings in 12+••. The diradical dication 12+•• features a robust triplet ground state, representing the first example of a high-spin sulfur-hydrocarbon diradical.

Stanniocalcin-2 (STC2) is a glycoprotein that has been found to play key roles in the regulation of cancer, diabetes mellitus, and osteogenesis. Herein we sought to extend these past studies by examining the importance of STC2 in the context of human mesenchymal stem cell (hMSC) adipogenic differentiation and exploring the mechanisms underlying such importance. We found that STC2 expression was significantly reduced on day 7 of hMSC adipogenesis. When we deliberately overexpressed STC2 in these cells, this resulted in significantly decreased expression of both peroxisome proliferator-activated receptor γ (PPARγ) and Fatty Acid Binding Protein-4 (FABP4) together with increased extracellular-signal regulated kinase 1/2 (ERK1/2) phosphorylation and markedly reduced lipid droplet formation within cells. Treatment of cells using the ERK inhibitor U0126 disrupted this ERK1/2 phosphorylation and restored the adipogenic differentiation of these hMSCs. When we instead knocked down STC2 expression, the opposite phenotypes were observed. Together these findings thus reveal that STC2 modulates ERK1/2 signaling in hMSCs so as to suppress their adipogenic differentiation.

The lanthanide complexes [Cp*2Ln][N,N′-bpyB] (1: Ln = Dy; 3: Ln = Gd; Cp* = pentamethylcyclopentadienyl) and [222-cryptand-K][(Cp*2Ln)(N,N′-bpyB)] (2: Ln = Dy; 4: Ln = Gd) bearing the redox-noninno...

Azo radical anion 1˙− and dianion 12− have been isolated by one- and two-electron reduction of the azo compound 1 (ArNNAr, Ar = 4-CN-2,6-iPr2-C6H2) with alkali metals, respectively. The reduced species have been characterized by single-crystal X-ray analysis, EPR, UV and FT-IR spectroscopy, as well as SQUID measurements. The filling of one and two electrons in the π* orbital of the N–N double bond of 1 leads to a half-double N–N bond in 1˙− and a single N–N bond in 12−. The uncoordinated nature of these reduced species enables them to activate CO2. The exposure of 1˙− solution to CO2 led to the formation of oxalate anion C2O42−, while that of 12− solution to CO2 afforded the hydrazine dicarboxylate dianion [1-2CO2]2−, which reversibly dissociated back to 1 and CO2 upon oxidation.