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The dynamics of polymer nanocomposites varies depending on the physics and chemistry at the polymer–nanoparticle interface. The physical aging of the nanocomposites is accelerated or retarded based on interfacial interactions and the state of polymer adsorption at the interfaces. In this study, we investigated the aging kinetics of silica–polystyrene nanocomposites using differential scanning calorimetry, focusing on the effect of local conformations of chains adsorbed on the nanofiller surface. The results show that the temperature dependence of the aging rate follows a Vogel–Fulcher–Tammann relationship at high temperatures, whereas it exhibits an Arrhenius-like behavior below a characteristic temperature (Tc). Notably, at T < Tc, the aging rate decreases with increasing loop height of the chains adsorbed on the filler surface, but the activation energy remains unchanged. We proposed that the suppression of the aging rate at T < Tc is likely related to an increase in the length scale over which the slow interfacial dynamics can propagate due to the increased topological interactions between the chain loops of a larger size and the free chains in the matrix. The increased packing frustration occurring at the filler surface occupied by the larger loops might also contribute to the decreased aging rate. [ABSTRACT FROM AUTHOR]

A method based on the PeakForce QNM atomic force microscopic (AFM) adhesion measurement is employed to investigate the glassy dynamics of polystyrene (PS) single-chain particles end-grafted to SiO2—Si substrates with different diameters, D0, of 3.4 nm–8.8 nm and molar masses, Mn, of 8–123 kg/mol. As temperature was increased, the adhesion force, Fad, experienced by the AFM tip on pulling off the single chains after loading demonstrated a stepwise increase at an elevated temperature, which we identified to be Tg based on previous works. Our result shows that Tg of our grafted single chains increases with Mn in a manner consistent with the Fox–Flory equation, but the coefficient quantifying the Mn dependence of Tg is only (36 ± 6)% the value of bulk PS. In addition, the value of Tg in the Mn → ∞ limit is about 25 °C below the bulk Tg but more than 15 °C above that of (untethered) PS nanoparticles with D0 ≈ 100 nm suspended in a solution. Our findings are consistent with Tg of our single chains being dominated by simultaneous effects of the interfaces, which depress Tg, and end-grafting, which enhances Tg. The latter is believed to exert its influence on the glass transition dynamics by a mechanism reliant on chain connectivity and does not vary with chain length. [ABSTRACT FROM AUTHOR]

Coronavirus disease-2019 (COVID-19) has now entered its third year as a worldwide pandemic. Unlike the Unites States, over 90% of patients have used traditional Chinese medicine (TCM) in China combined with conventional western medicine. The present minireview/commentary summarizes the experiences of TCM in the treatment of COVID-19 combined with conventional western medicine, lessons from the United States and some additional insights. COVID-19 falls into the category of "dampness−toxin plague" and is divided into five stages: mild stage, moderate stage, severe stage, critical stage, and recovery stage. Clinical trials conducted in China have suggested that TCM treatment plays a significant role in alleviating clinical symptoms, decreasing the time of hospitalization, reducing the overall fatality rate, and providing other beneficial outcomes when combined with conventional western medicine. To date, TCM is not widely used in the American hospital system. Only one TCM clinical trial to treat mild to moderate COVID-19 has been registered with ClinicalTrials.gov. A suggestion of dialogues among associated parties is proposed. TCM has been used as part of an integrative medicine treatment paradigm combined with conventional western medicine for COVID-19 in China. As registered clinical trials combining conventional western medicine with TCM continue to be produced and show positive benefits, the possibilities for TCM integration into treatment protocols for COVID-19 will become more of a possibility in the United States. [ABSTRACT FROM AUTHOR]

Background. The composition and metabolic activities of gut microbiota are strongly interconnected with cardiac fibrosis (CF) and heart failure (HF). Qige Huxin formula (QHF), a traditional Chinese medicine (TCM) formulation originating from a classical Fangji Huangqi decoction, has been widely used to clinically treat HF for decades. However, it is still unclear whether QHF alleviates CF by modulating gut microbiota and intestinal integrity. Purpose. This study aimed to investigate the cardioprotective effects of QHF in isoprenaline-induced CF through modulating gut microbiota and intestinal integrity. Methods. Fifty mice were randomly divided into five groups after one week of acclimatization feeding: control group, model group, 2.56 g/kg/d group (low-dose QHF), 5.12 g/kg/d group (high-dose QHF), and meto group (15 mg/kg/d). The CF model was established by subcutaneously injecting the mice with isoprenaline (10 mg/kg/d for 14 days), followed by QHF treatment. The heart volume, cardiac weight index (CWI), serum myocardial enzymes, serum inflammatory cytokines, serum lipopolysaccharide, histopathology of the heart and colon tissues, ZO-1, and occludin of colon tissues were then measured. Fecal samples from mice were analyzed using 16S rRNA sequencing. Results. QHF treatment significantly reduced heart volume, CWI, and serum CK and CK-MB levels, attenuated cardiac histopathological alterations, and alleviated CF. QHF treatment also downregulated TNF-α, IL-1β, and IL-6 in serum. Moreover, QHF treatment decreased the serum level of lipopolysaccharide and maintained intestinal integrity by upregulating ZO-1 and occludin. The 16S rRNA microbiota analysis revealed that QHF treatment increased the relative abundance of Marvinbryantia and Phascolarctobacterium. Conclusions. QHF treatment exerts cardioprotective effects through modulating gut microbiota, protecting intestinal integrity, and alleviating inflammation. This study shows that gut microbiota may enhance heart-gut interaction. [ABSTRACT FROM AUTHOR]

Aim: Gut microbiota is of crucial importance to cardiac health. Astragaloside IV (AS-IV) is a main active ingredient of Huangqi, a traditional edible and medicinal herb that has been shown to have beneficial effects on cardiac fibrosis (CF). However, it is still uncertain whether the consumption of AS-IV alleviates cardiac fibrosis through the gut microbiota and its metabolites. Therefore, we assessed whether the anti-fibrosis effect of AS-IV is associated with changes in intestinal microbiota and fecal metabolites and if so, whether some specific gut microbes are conducive to the benefits of AS-IV. Methods: Male C57BL-6J mice were subcutaneously injected with isoprenaline (ISO) to induce cardiac fibrosis. AS-IV was administered to mice by gavage for 14 days. The effects of AS-IV on cardiac function, myocardial enzyme, cardiac weight index (CWI), and histopathology of ISO-induced CF mice were investigated. Moreover, 16S rRNA sequencing was used to establish gut-microbiota profiles. Fecal-metabolites profiles were established using the liquid chromatograph-mass spectrometry (LC-MS). Results: AS-IV treatment prevented cardiac dysfunction, ameliorated myocardial damage, histopathological changes, and cardiac fibrosis induced by ISO. AS-IV consumption increased the richness of Akkermansia, Defluviitaleaceae_UCG-011, and Rikenella. AS-IV also modulated gut metabolites in their feces. Among 141 altered gut metabolites, amino acid production was sharply changed. Furthermore, noticeable correlations were found between several specific gut microbes and altered fecal metabolites. Conclusions: An increase of Akkermansia, Defluviitaleaceae_UCG-011, and Rikenella abundance, and modulation of amino acid metabolism, may contribute to the anti-fibrosis and cardiac protective effects of Astragaloside IV. [ABSTRACT FROM AUTHOR]

Two challenging scientific disciplines, i.e., the physics of glasses [Anderson, Science 267, 1615 (1995); Kennedy and Norman, Science 309, 75 (2005)] and interface chemistry [Sanders, 125 Questions: Exploration and Discovery (Science/AAAS, 2021); Yates and Campbell, Proc. Natl. Acad. Sci. U. S. A. 108, 911 (2011)], converge in research on the dynamics of glass surfaces. In recent decades, studies have revealed that glasses exhibit profound alterations in their dynamics within nanometers of interfaces. Rather, at the free surfaces of glassy materials with arrested bulk dynamics, a highly mobile ultrathin layer is present, wherein molecular mobility is much faster than in the bulk. Enhanced surface mobility has become an important scientific concept and is intrinsic and universal to various categories of glasses (e.g., molecular, metallic, and polymeric glasses), thus having technological implications for processing and applications of glasses. This review provides a comprehensive summary of the historical evolution of the concept, characterization, theoretical modeling, and unique features of dynamics at the surfaces of glasses. Additionally, this paper also illustrates potential advantages of incorporating this concept into designing improved materials with extraordinary properties. We hope this review article will contribute to the current understanding of the unique surface dynamics of glassy materials. [ABSTRACT FROM AUTHOR]

Background: The outbreak of coronavirus disease 2019 (COVID-19) has rapidly spread to become a global emergency since December 2019. Chinese herbal medicine plays an important role in the treatment of COVID-19. Chinese herbal medicine honeysuckle is an extremely used traditional edible and medicinal herb. Many trials suggest that honeysuckle has obtained a good curative effect for COVID-19; however, no systematic evaluation on the clinical efficacy of honeysuckle in the treatment of COVID-19 is reported. This study aimed to evaluate the efficacy and safety of Chinese herbal medicine honeysuckle in the treatment of COVID-19. Methods: Seven electronic databases (PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure, China Science and Technology Journal Database, Wanfang Database, and China Biology Medicine) were searched to identify randomized controlled trials (RCTs) of honeysuckle for adult patients (aged ≥ 18 years) with COVID-19. The Cochrane Risk of Bias Tool was applied to assess the methodological quality of trials. Review Manager 5.3 software was used for data analysis. Results: Overall, nine RCTs involving 1,286 patients were enrolled. Our meta-analyses found that combination therapy of honeysuckle and conventional therapy was more effective than conventional therapy alone in lung computed tomography (CT) [relative risk (RR) = 1.24, 95% confidence interval (95%CI) (1.12, 1.37), P < 0.0001], clinical cure rate [RR = 1.21, 95%CI (1.12, 1.31), P < 0.00001], and rate of conversion to severe cases [RR = 0.50, 95%CI (0.33, 0.76), P = 0.001]. Besides, combination therapy can improve the symptom score of fever, cough reduction rate, symptom score of cough, and inflammatory biomarkers (white blood cell (WBC) count; C-reactive protein (CRP)) (P < 0.05). Conclusion: Honeysuckle combined with conventional therapy may be beneficial for the treatment of COVID-19 in improving lung CT, clinical cure rate, clinical symptoms, and laboratory indicators and reducing the rate of conversion to severe cases. Besides, combination therapy did not increase adverse drug events. More high-quality RCTs are needed in the future. [ABSTRACT FROM AUTHOR]

Introduction: Coronavirus disease 2019 (COVID-19) has emerged as a global pandemic since its outbreak in Wuhan, China. It is an urgent task to prevent and treat COVID-19 effectively early. In China's experience combating the COVID-19 pandemic, Chinese herbal medicine (CHM) has played an indispensable role. A large number of epidemiological investigations have shown that mild to moderate COVID-19 accounts for the largest proportion of cases. It is of great importance to treat such COVID-19 cases, which can help control epidemic progression. Many trials have shown that CHM combined with conventional therapy in the treatment of mild to moderate COVID-19 was superior to conventional therapy alone. This review was designed to evaluate the add-on effect of CHM in the treatment of mild to moderate COVID-19. Methods: Eight electronic databases including PubMed, EMBASE, Cochrane Central Register of Controlled Trials, the Clinical Trials.gov website, China National Knowledge Infrastructure (CNKI), China Science and Technology Journal Database (VIP), Wanfang Database and China Biology Medicine (CBM) were searched from December 2019 to March 2021 without language restrictions. Two reviewers searched and selected studies, and extracted data according to inclusion and exclusion criteria independently. Cochrane Risk of Bias (ROB) tool was used to assess the methodological quality of the included RCTs. Review Manager 5.3.0 software was used for statistical analysis. Results: Twelve eligible RCTs including 1393 participants were included in this meta-analysis. Our meta-analyses found that lung CT parameters [RR = 1.26, 95% CI (1.15, 1.38), P<0.00001] and the clinical cure rate [RR = 1.26, 95%CI (1.16, 1.38), P<0.00001] of CHM combined with conventional therapy in the treatment of mild to moderate COVID-19 were better than those of conventional therapy. The rate of conversion to severe cases [RR = 0.48, 95%CI (0.32, 0.73), P = 0.0005], TCM symptom score of fever [MD = -0.62, 95%CI (-0.79, -0.45), P<0.00001], cough cases [RR = 1.43, 95%CI (1.16, 1.75), P = 0.0006], TCM symptom score of cough[MD = -1.07, 95%CI (-1.29, -0.85), P<0.00001], TCM symptom score of fatigue[MD = -0.66, 95%CI (-1.05, -0.28), P = 0.0007], and CRP[MD = -5.46, 95%CI (-8.19, -2.72), P<0.0001] of combination therapy was significantly lower than that of conventional therapy. The WBC count was significantly higher than that of conventional therapy[MD = 0.38, 95%CI (0.31, 0.44), P<0.00001]. Our meta-analysis results were robust through sensitivity analysis. Conclusion: Chinese herbal medicine combined with conventional therapy may be effective and safe in the treatment of mild to moderate COVID-19. More high-quality RCTs are needed in the future. [ABSTRACT FROM AUTHOR]

Many emerging materials, such as ultrastable glasses1,2 of interest for phone displays and OLED television screens, owe their properties to a gradient of enhanced mobility at the surface of glass-forming liquids. The discovery of this surface mobility enhancement3–5 has reshaped our understanding of the behaviour of glass formers and of how to fashion them into improved materials. In polymeric glasses, these interfacial modifications are complicated by the existence of a second length scale—the size of the polymer chain—as well as the length scale of the interfacial mobility gradient6–9. Here we present simulations, theory and time-resolved surface nano-creep experiments to reveal that this two-scale nature of glassy polymer surfaces drives the emergence of a transient rubbery, entangled-like surface behaviour even in polymers comprised of short, subentangled chains. We find that this effect emerges from superposed gradients in segmental dynamics and chain conformational statistics. The lifetime of this rubbery behaviour, which will have broad implications in constraining surface relaxations central to applications including tribology, adhesion, and surface healing of polymeric glasses, extends as the material is cooled. The surface layers suffer a general breakdown in time−temperature superposition (TTS), a fundamental tenet of polymer physics and rheology. This finding may require a reevaluation of strategies for the prediction of long-time properties in polymeric glasses with high interfacial areas. We expect that this interfacial transient elastomer effect and TTS breakdown should normally occur in macromolecular systems ranging from nanocomposites to thin films, where interfaces dominate material properties5,10.Surface enhancements in glass mobility are complicated in polymers by the interplay of the surface mobile layer thickness with a second length scale (the size of the polymer chains), giving rise to a transient rubbery surface even in polymers with short chains. [ABSTRACT FROM AUTHOR]

BACKGROUND: At present. extrusion is widely used in total knee arthroplasty. Studies have shown that extrusion can aggravate early pain and increase the risk of romplications after operation. Therefore, a safer and more effective method it is urgently needed in clinic. OBJECTIVE: To observe the effects of elevation and extrusion of blood-expelling method on clinical outcomes during total knee arthroplasty. METHODS: Sixty-four patients who were scheduled to undergo unilateral total knee arthroplasty for the first time were randomly divided into two groups. During total knee arthroplasty, the control group received extrusion method, while the experimental group received elevation method. The main outromes of the two groups were rompared: visual analogue scale score, knee joint swelling, C-reactive protein, serum creatine kinase activity and postoperative complications; secondary outcomes: tourniquet use time, Hospital for Special Surgery score, and SF-36 score. RESULTS AND CONCLUSION: (1) Visual analogue scale scores in the experimental group were significantly lower than those in the control group on the first day, the seventh day, the first month and the third month after operation (P < 0.05). (2) Knee swelling, serum creatine kinase and C-reactive protein increased in both groups after operation, but the increase in experimental group was significantly lower than that in control group (P < 0.05). (3) In terms of postoperative complications, the incidences of tension vesicles and deep vein thrombosis in the control group were higher than those in the experimental group (P < 0.05). The total complication rate was signifJCSnUy higher in the control group than in the experimental group (P < 0.05). (4) There was no significant difference in tourniquet use tine between the two groups (P > 0.05). (5) Hospital for Special Surgery score and SF-36 score were assessed at 1, 3 and 6 months. The results showed that it was better than before, but there was no signifiCant difference between the two groups (P > 0.05). (6) In conclusion, elevation of blood-expelling method could alleviate early pain response, reduce inflammation reaction and soft tissue injury, and decrease the incidence of skin tension blisters and thromboembolism. It is in line with the concept of rapid recovery. Therefore, during total knee arthroplasty, elevation of blood-expelling method is a safer and more effective method than extrusion. [ABSTRACT FROM AUTHOR]

Annealing a supported polymer film in the melt state results in the growth of an irreversibly adsorbed layer, which has been shown to influence thin film properties such as diffusion and glass transition temperature. Adsorbed layer growth is attributed to many simultaneous interactions between individual monomer units and the substrate, stabilizing chains against desorption. In this study, adsorbed layers of polystyrene (PS), poly(methyl methacrylate) (PMMA), and their random copolymers are isolated by select solvents. While PS adsorbed layer thickness is largely unaffected by the choice of washing solvent, the PMMA adsorbed layer completely desorbs when washed with tetrahydrofuran and chloroform, as opposed to toluene. Scaling relationships between adsorbed layer thickness and degree of chain adsorption at the substrate enable the use of adsorbed layer thickness to probe specific polymer‐substrate interactions. Composition‐dependent desorption trends indicate non‐preferential adsorption between styrene and methyl methacrylate repeat units at the substrate, despite differences in substrate interaction strength. This insight contributes to the developing mechanism for the adsorption of random copolymers during melt‐state annealing, further extending the ability to predict processing‐inducted changes to the properties of polymer thin films to heterogeneous systems. [ABSTRACT FROM AUTHOR]

BACKGROUND: Unicompartmental knee osteoarthritis can be treated clinically with either total or partial knee arthroplasty. In the choice of treatment methods, a variety of factors lead to significant differences. There is little reliable evidence to guide the clinical surgical options OBJECTIVE: To compare the short-term curative effect of unicompartmental and total knee arthroplasties in the treatment of unicompartmental osteoarthritis and to explore the effects of two treatment methods on the balance function of patients. METHODS: This was a perspective trial. The patients with unicompartmental knee osteoarthritis were divided into unicompartmental knee arthroplasty group (22 cases, 23 knees) and total knee arthroplasty group (30 cases, 30 knees) based on surgical method. All patients signed the informed consents and the study was approved by the hospital ethical committee. The operation time, hospitalization time, Hospital for Special Surgery score, and the range of motion of the knee joint were compared between two groups to evaluate the early efficacy. The patients' balance function was evaluated using the Tecnobody Proprioception Test System, Timed Up and Go test, and Berg Balance Scale before and 3 months after surgery. RESULTS AND CONCLUSION: (1) Compared with the total knee arthroplasty group, the unicompartmental knee arthroplasty group had shorter operation time and hospitalization time (P < 0.001 ). (2) At 3 months after surgery, there was no significant difference in the Hospital for Special Surgery score, range of motion of the knee joint, Timed Up and Go test or Berg Balance Scale score between two groups (P > 0.05). The Tecnobody Proprioception Test System scores at 3 months after surgery in the unicompartmental knee arthroplasty group were significantly higher than those in the total knee arthroplasty group (P < 0.001 ). (3) These results indicate that both unicompartmental and total knee arthroplasties have satisfactory short-term results in the treatment of unicompartmental knee osteoarthritis. Unicompartmental knee arthroplasty is superior to total knee arthroplasty in terms of operation time, hospitalization time, and balance function recovery. [ABSTRACT FROM AUTHOR]

For most graphene electrodes, there is usually a disappointing trade-off relationship between gravimetric and volumetric capacitive characteristics, which is definitely a major stumbling block in the development of real-life supercapacitors with high energy density. Herein, we rationally designed a hierarchically porous and modestly packed diamine pillared graphene, which is achieved by a facile and straightforward reaction between commercialized bulk graphite fluoride and in situ generated diamine anions. Combined reliable characterization studies demonstrate that an advantageous reductive defluorination of the unsubstituted carbon–fluorine units (C–Fx) accompanies the foreseen substitution of C–Fx by diamines, endowing the resultant products with recovered 2D π-conjugation and high conductivity. In comparison to ethylenediamine and p-phenylenediamine, pseudocapacitive 4,4′-oxydianiline (ODA) molecular pillars, having a bulky and rigid geometry, provide the ODA-G product with a greatly widened d-spacing (6.2 Å), large wettable and electrolyte-accessible specific surface area (1985 m2 g−1), hierarchically porous and interconnected structuration, heavyweight nature (density of 1.08 g cm−3), etc. Consequently, the symmetric supercapacitor fabricated using ODA-G as both electrodes delivers an impressive gravimetric capacitance of 328.5 F g−1 and a maximized volumetric capacitance of 354.8 F cm−3 at a current density of 0.5 A g−1, whilst exhibiting a remarkable rate capability and cycling stability. Apart from an exceptional gravimetric energy density, the volumetric energy density of the ODA-G device is as high as 19.5 W h L−1 at a large power density of 9093 W L−1. It is notable that this contribution deepens our insight into the chemistry of graphite fluoride, and can guide the judicious design and synthesis of versatile functionalized graphene applicable to other electrochemical energy-storage systems, or the newly-emerging photothermal water evaporation, desalination, etc. [ABSTRACT FROM AUTHOR]

Flexible transparent conductive films (TCFs) fabricated from indium tin oxide (ITO)-alternative materials are highly desirable for a variety of present and future (opto-)electronics. In this contribution, we report that the hybridization of a kind of two-dimensionally electro-conductive material and a kind of one-dimensionally electro-conductive material, i.e. reduced graphene oxide (rGO) and copper nanowires (CuNWs), is a good choice to meet such desire. Different combination ratios between these two kinds of materials by either adding CuNWs into rGO bulk or vice versa were tested. It was found that a significant synergistic effect in improving TCF performance takes place between two-dimensional (2D) rGO nanosheets and one-dimensional (1D) copper nanowires. That is, 1D metallic CuNWs are superior to 2D rGO nanosheets as a conducting additive to improve the performance of TCFs mainly based on the rGO material, while 2D rGO nanosheets rather than 1D CuNWs are very good additives for CuNW-based TCFs to decrease sheet resistance with a small sacrifice in film transparency. Moreover, the hybridization of CuNWs with rGO can not only significantly reduce datum fluctuation in sheet resistance, but also improve the anti-oxidation and anti-foldability properties of TCFs mainly based on CuNWs. Finally, flexible TCFs with a transmittance at 550 nm larger than 80% and a sheet resistance down to 50 Ω sq−1 have been achieved on a polyethylene terephthalate (PET) substrate. [ABSTRACT FROM AUTHOR]

ABSTRACT In this article, the fluorinated amphiphilic V-shaped brushes with two highly incompatible arms of mPEG42 and PMMA38- b-PFMAy were produced by reacting COOH in the PAA segment in methoxypoly(ethylene glycol)- b-poly(acrylic acid)- b-poly(methyl methacrylate)- b-poly(2-perfluoro-octylethyl methacrylate) (mPEG42- b-PAA11-b-PMMA38- b-PFMAy) with an epoxy group on the functionalized SiO2 substrate. It was found that the resulting phase separation structures of the V-shaped brushes can be adjusted by altering the degree of polymerization ( y) of PFMA. The brush surface with y = 8 showed an alternating phase separation structure, in which one domain was water-soluble PEG and the other was ultralow surface energy domain with a crystalline fluorinated side group. Protein adsorption studies indicated that this surface structure exhibited desirable protein-resistant performance. The reason was attributed to the stimuli-responsive PEG domain, in which PEG chains stretch out at the interface in water, while the PFMA domain remains relatively stable. The synergistic effect of the hydrophilic PEG domain and the hydrophobic PFMA domain in water prevents protein adsorption. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 2599-2610 [ABSTRACT FROM AUTHOR]

Acrylate block polymer brushes (Au-PMMA65-b-PODMAy-ec-FMA2) with two 2-perfluorooctylethyl methacrylate units at the brush end were successfully prepared on an Au substrate using a “grafting to” method. Characterization by XPS, contact angle measurement, ellipsometry and nanomechanical measurement showed that a well-ordered and perpendicularly oriented structure of the perfluoroalkyl side chains on the brush surface was enhanced with an increasing degree of polymerization (y) of poly (n-octadecyl methacrylate), and a crystalline structure of perfluoroalkyl side chains formed when y was equal to 24. Protein adsorption studies indicated that the adsorbed mass of fibrinogen decreased with an increasing order of the structure of the perfluoroalkyl side chains at the brush end. When the perfluoroalkyl group on the brush surface formed a crystal structure, there was only trace fibrinogen adsorption on the brush surface. This work demonstrates that the protein-resistant performance was enhanced greatly by constructing polymer brush surfaces with well-ordered and perpendicularly oriented structures of the perfluoroalkyl side chains. [ABSTRACT FROM AUTHOR]

The surface chemical structure development in solution-cast styrene(S)/butadiene(B) block copolymer films as a function of solvent evaporation time was investigated using sum frequency generation vibrational spectroscopy (SFG). The surface structure formation of the styrene(S)/butadien(B) block copolymer (30 wt% PS) films during the solution-to-film process was found to be controlled mainly by dynamic factors, such as the mobility of the PB block in solution. For SB diblock copolymers, a pure PB surface layer was formed only when the film was cast by dilute toluene solution. With increasing concentration of casting solution, PB and PS components were found to coexist on the film surface, and the morphology of the PB component on the film surface changed from cylindrical rods to spheres. For SBS triblock copolymers, a small amount of PS component existed on the surface even if the film was cast by 1.0 wt% toluene solution. In addition, PS components at the outermost layer of the film increased and the length of PB cylindrical rods on the surface decreased with increasing concentration of casting solution. [ABSTRACT FROM AUTHOR]

Graphite fluoride‐launched graphene functionalization has attracted increasing interest in recent years. Highly basic nucleophiles are normally employed for ultrastrong CF bonding. However, frequently, an appreciable majority of C–F units of graphite fluoride are reductively eliminated, leading to low functionalization degrees. It is hypothesized that graphite fluoride could likely be functionalized to a larger degree by lowering the basicity of the nucleophiles. Herein, ultraweakly basic NH3·H2O is adopted as a nucleophile to react with extremely inert graphite fluoride, and the resulting reaction affords amino/hydroxyl cofunctionalized graphene (NH2–G–OH). As expected, the NH2/OH functionalization degree and the ratio of substituted C–F units to reduced ones reach high values of 0.34 and 1.62, respectively. Due to the dual energy‐storage mechanisms of the electrochemical double‐layer capacitance coupled with Faradaic pseudocapacitance, the NH2–G8–OH‐based all‐solid‐state supercapacitors are flexible and robust and deliver state‐of‐the‐art capacitive characteristics, while exhibiting high rate capability and electrochemical cycling stability. In addition, NH2/OH moieties remain highly reactive to be post‐functionalized by versatile electrophiles, not only achieving an umpolung of graphite fluoride, but also enabling NH2–G8–OH a competitive alternative to monopolistic GO, and opening up an innovative pathway for development of high‐performance graphene derivatives amenable to multifarious applications. [ABSTRACT FROM AUTHOR]

It is mostly reported that graphene lattice doped/codoped with heteroatoms (e.g., nitrogen and boron) in an in‐plane fashion exhibits an impressive oxygen reduction reaction (ORR) electrocatalytic efficiency when serving as a metal‐free catalyst, but the cases that graphene sheets functionalized with heteroatoms in an out‐plane scenario are rarely involved. Herein, amino (NH2)‐/fluoro (F)‐cofunctionalized graphene (NH2GF) is rationally designed and synthesized both in out‐plane modes through a programmable substitutive/reductive defluorination toward bulk graphite fluoride using NaNH2. Versatile NH2‐/F‐(co)functionalized graphene products with tunable fluorination and amination are readily yielded and their ORR electrocatalysis is evaluated. Intriguingly, the parameter of NH2/F molar ratio is determinative for their electrocatalytic performances. Consequently, graphene product (roughly formulated in (NH2)7.0C100F2.8, vide infra) dually functionalized with NH2 and F and with an optimized NH2/F factor of 2.5 outperforms others—overmuch in either NH2 only or F only. Encouragingly, (NH2)7.0C100F2.8 even delivers a slightly better electrocatalytic activity than Pt/C catalyst. This finding implies a significant synergistic effect between NH2 and F in boosting graphene electrocatalysis. Apart from fantastic electrocatalytic activity, (NH2)7.0C100F2.8 also exhibits remarkable resistance to crossover effect and exceptional cycling stability. A remarkable NH2‐/F‐cofunctionalized graphene electrocatalyst featured with a nonmainstream out‐plane doping mode is rationally designed and synthesized by an innovative methodology, in which nonpopular graphite fluoride is employed as the starting material and reacted with NaNH2. The coexistence and the significant synergistic effect between NH2 and F make NH2‐/F‐cofunctionalized graphene more electrocatalytically active than Pt/C. [ABSTRACT FROM AUTHOR]

Various silicon nitride (SiN) films were prepared using plasma enhanced chemical vapor deposition (PECVD) by tuning deposition condition to control initial hydrogen in the films. The as-deposited films, which exhibit different tensile stress from 0.2 to 1.2 GPa, were treated by ultraviolet (UV) curing to investigate how the stress and shrinkage response to film initial hydrogen state and how to modify SiN hydrogen state by deposition condition to achieve high tensile stress. The results show that the stress and shrinkage of SiN films response quite differentially to UV curing depending on hydrogen state. Stress of SiN was hardly tuned by UV curing in case of Si–H deficiency, but largely increased in case of balanced Si–H and N–H bonds. Both high and low stress-tunable SiN films were used as contact etch stop layer (CAESL) in 45 nm bulk device. Device performance (Ion–Ioff) has been improved by about 5% using high stress-tunable SiN film. [ABSTRACT FROM AUTHOR]

Sterol o-acyltransferase 1 (Soat1, also known as ACAT1) is an endoplasmic reticulum enzyme that catalyzes free cholesterol to cholesterol ester. We identified four single-nucleotide polymorphisms (SNPs) (A421C, A439G, C454T, and C613T) within the coding region of Soat1 between mouse strains C57BL/6 (B6) and C3H and two of the SNPs led to amino-acid substitutions (IIe147Val and His205Tyr). We then sequenced the coding region of Soat1 in 33 additional mouse strains and found three Soat1 protein variants, including 147IIe 205His, 147Va1205His, and 147Va1205Tyr. When fed a high fat/cholesterol diet with cholate for 8 weeks, mouse strains with the 147Va1205His variant had significantly higher non-HDL levels (343 ± 161 vs. 140 ± 43 or 129 ± 70, P = 9.9E-05 in female; 331 ± 240 vs. 127 ± 47 or 122 ± 93; P = 0.0039 in male), smaller body weight (13 ± 1 vs. 23 ± 5 or 26 ± 5, P = 0.0009 in female; 15 ± 1 vs. 28 ± 6 or 30 ± 4; P = 0.0002 in male), and were absent in aortic fatty streak lesions (0 vs. 343 ± 501 or 259 ± 690 in female P =0.65; and 553 ± 961 or 287 ± 1036 in male; P =0.58). Thus, these results support Soat1 to be an important gene contributing to hyperlipidemia, body weight, and atherosclerosis in mice. [ABSTRACT FROM AUTHOR]