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It is still a huge challenge to introduce effective crack‐healing ability into energetic composites with a high oxidizer content. In this article, a poly(urea‐urethane) energetic elastomer was prepared by the polycondensation reaction of glycidyl azido polymer (GAP), isophorone diisocyanate (IPDI), and 2‐aminophenyl disulfide (2‐APD). In the poly(urea‐urethane) elastomer structure, the hybrid dynamic lock, including multilevel H‐bonds and disulfide bonds, not only provides abundant dynamic interactions and promotes chain diffusion, but also enhances physical crosslinking density. Such a unique design fabricated the energetic elastomer with robust tensile strength (0.72 MPa), high stretchability (1631%), and outstanding toughness (8.95 MJ/m3) in the field of energetic polymers. Meanwhile, this energetic elastomer exhibited high self‐healing efficiency (98.4% at 60 °C) and heat release (Q = 1750.46 J/g). Experimental and theoretical results adequately explain the self‐healing mechanism, particularly the role of azido units. The high‐solid content (80 wt%) energetic composites based on the energetic elastomer presented outstanding micro‐defect self‐healing (97.8%) and recycling without loss of mechanical performance. The development of smart energetic composites with excellent self‐healing and recyclable ability provides a meaningful way for a wide range of applications in the field of energetic materials. [ABSTRACT FROM AUTHOR]

Hand flexor tendon injuries are common and biomechanically challenging to achieve good functional outcomes. Several approaches using the Pennington‐modified Kessler repair technique have been attempted, but high‐level evidence is still lacking. Here, we evaluated the relative efficacy of three versions of the Pennington‐modified Kessler technique in repairing complete flexor digitorum profundus (FDP) laceration in Zone 1. We conducted a 2‐year, single‐center, double‐blind, randomized clinical trial involving 85 patients with 105 digits enrolled between June 1, 2017 and January 1, 2019. Eligible participants were 20–60 years of age and underwent tendon repair in the acute phase for complete FDP laceration distal to the insertion of the superficial flexor tendon. The digits were randomized 1:1:1 to three treatment groups: (1) Pennington‐modified Kessler repair; (2) Pennington‐modified Kessler repair followed by circumferential tendon suture; or (3) Pennington‐modified Kessler repair followed by circumferential epitenon suture. The primary endpoint was total active range of motion (TAROM) at 2 years after the initial surgery. The secondary endpoint was the reoperation rate. Compared with group 1, both techniques for peripheral suture were associated with a decrease in TAROM at 2 years after surgery. The total reoperation rates of the three groups were 11.4%, 18.2%, and 17.6%, and we found no significant differences among the three groups possibly due to the limited sample size. Unexpectedly, among participants with complete FDP laceration in Zone I, both circumferential‐tendon and circumferential‐epitenon sutures caused worsening of TAROM after 2 years. No conclusions can be drawn regarding reoperation rates among the groups. Level of evidence: Therapeutic level I. [ABSTRACT FROM AUTHOR]

Background: The extensive functional and structural remodeling that occurs in the brain after amputation often results in phantom limb pain (PLP). These closely related phenomena are still not fully understood. Methods: Using magnetic resonance imaging (MRI) and graph theoretical analysis (GTA), we explored how alterations in brain cortical thickness (CTh) and structural covariance networks (SCNs) in upper limb amputees (ULAs) relate to PLP. In all, 45 ULAs and 45 healthy controls (HCs) underwent structural MRI. Regional network properties, including nodal degree, betweenness centrality (BC), and node efficiency, were analyzed with GTA. Similarly, global network properties, including global efficiency (Eglob), local efficiency (Eloc), clustering coefficient (Cp), characteristic path length (Lp), and the small‐worldness index, were evaluated. Results: Compared with HCs, ULAs had reduced CThs in the postcentral and precentral gyri contralateral to the amputated limb; this decrease in CTh was negatively correlated with PLP intensity in ULAs. ULAs showed varying degrees of change in node efficiency in regional network properties compared to HCs (p < 0.005). There were no group differences in Eglob, Eloc, Cp, and Lp properties (all p > 0.05). The real‐worldness SCN of ULAs showed a small‐world topology ranging from 2% to 34%, and the area under the curve of the small‐worldness index in ULAs was significantly different compared to HCs (p < 0.001). Conclusion: These results suggest that the topological organization of human CNS functional networks is altered after amputation of the upper limb, providing further support for the cortical remapping theory of PLP. [ABSTRACT FROM AUTHOR]

With the continuous improvement of detection technology, the survivability of targets on the battlefield is facing great challenges. Consequently, microwave absorbers with stealth characteristics are of important research value to modern military. Aim at solving the problems of narrow bandwidth or complex structure, an implementation model of ultra‐wideband (UWB) absorber based on hybrid structure is proposed. In this letter, a polarization‐insensitive ultra‐wideband absorber (PIUWA) is designed, manufactured, and characterized, which has a good absorptivity of more than 90% ranges from 4 to 24.53GHz (the fractional bandwidth [FBW] is 144%) by triggering multiple resonance peaks in the hybrid structure. In addition, the subwavelength periodicity of the PIUWA is theoretically beneficial to the angular stability under full‐wave polarizations. The operating mechanism of the PIUWA is demonstrated by the equivalent circuit model and the correctness of the design is verified by experimental measurements. This letter contributes to the approach of designing and fabricating UWB microwave absorbers with high absorptivity, good angular stability, and simpler assembly procedure. [ABSTRACT FROM AUTHOR]

The volatile flavor compounds of Huangjiu (Chinese rice wine) brewed from different raw materials were obviously different, but there were few studies on the volatile flavor compounds of Huangjiu brewed from different wheat Qu at different brewing stages. In this paper, headspace–solid phase microextraction combined with gas chromatography–mass spectrometry, combined with principal component analysis and sensory evaluation, was used to determine the volatile flavor compounds in Huangjiu brewed from wheat Qu made by hand and wheat Qu made by mechanical. The results showed that there were significant differences in the contents and types of volatile flavor substances in Huangjiu brewed from different wheat Qu at fermentation stages, and the prefermentation and postfermentation Huangjiu samples could be well distinguished from each other. Compared with the Huangjiu brewed from wheat Qu made by mechanical, the Huangjiu brewed from wheat Qu made by hand has stronger aroma and better taste. [ABSTRACT FROM AUTHOR]

In order to improve the high cost of equipment and difficult management caused by the natural aging of Chinese rice wine (Huangjiu), micro‐oxygen (MO) and electric field (PEF) technology are used to accelerate the aging of Huangjiu. The results showed that micro‐oxygen and electric field have a significant effect on the sensory characteristics and flavor characteristics of Huangjiu. Compared with the naturally aged Huangjiu, the flavor compounds of Huangjiu treated with micro‐oxygen and electric field increase significantly. Based on principal component analysis, Huangjiu processed at 0.35 mg L/day or 0.5 mg L/day combined electric field exhibited similar flavor to the natural aged Huangjiu, which was highly associated with long‐chain fatty acid ethyl esters (C13–C18). Moreover, partial least squares regression demonstrated that sensory attributes of cereal aroma and astringency were highlighted after aging time, while fruit aroma, continuation, and full body were dominant after micro‐oxygen and electric field treatment. Micro‐oxygen and electric field effectively enhanced the quality of Huangjiu, which could be applied in other alcoholic beverages. [ABSTRACT FROM AUTHOR]

Background. Amputation in adults is a serious procedure or traumatic outcome, one that leads to a possible "remapping" of limb representations (somatotopy) in the motor and sensory cortex. The temporal and spatial extent underlying reorganization of somatotopy is unclear. The aim of this study was to better understand how local and global structural plasticity in sensory-motor cortical networks changes temporally and spatially after upper-limb amputation. Methods. We studied 8 healthy nonamputee control subjects and 16 complete upper-limb amputees. Resting-state MRI (rs-fMRI) was used to measure local and large-scale relative differences (compared to controls) in both the amplitude of low-frequency fluctuations (ALFF) and degree of centrality (DC) at 2 months, 6 months, and 12 months after traumatic amputation. Results. In amputees, rs-fMRI scans revealed differences in spatial patterns of ALFF and DC among brain regions over time. Significant relative increases in ALFF and DC were detected not only in the sensory and motor cortex but also in related cortical regions believed to be involved in cognition and motor planning. We observed changes in the magnitude of ALFFs in the pre- and postcentral gyrus and primary sensory cortex, as well as in the anterior cingulate, parahippocampal gyrus, and hippocampus, 2 months after the amputation. The regional distribution of increases/decreases in ALFFs and DC documented at 2-month postamputation was very different from those at 6 and 12-month postamputation. Conclusion. Local and wide-spread changes in ALFFs in the sensorimotor cortex and cognitive-related brain regions after upper-limb amputation may imply dysfunction not only in sensory and motor function but also in areas responsible for sensorimotor integration and motor planning. These results suggest that cortical reorganization after upper extremity deafferentation is temporally and spatially more complicated than previously appreciated, affecting DC in widespread regions. [ABSTRACT FROM AUTHOR]

Nickel cobaltite (NiCo2O4) nanostructures have been considered as promising bifunctional electrocatalyst materials for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in alkaline electrolyte. However, the activity of these materials toward overall water splitting is still unsatisfactory because a larger voltage is needed to drive the reactions. This study shows that more-efficient bifunctional catalysts based on NiCo2O4 materials can be obtained by adopting an integrated composite electrode with robust hollow structures. This novel electrode is constructed by the growth of hollow Ni@NiCo2O4 nanorod arrays on three-dimensional (3D) Ni foam. The interlayer of Ni hollow nanorods is conformally covered by NiCo2O4 nanosheets, providing large surface area and fast electron transport. Benefiting from these integrated characteristics, the hollow Ni@NiCo2O4 electrode as an oxygen evolution electrocatalyst can deliver a low overpotential of 270 mV at 10 mA cm−2 and present excellent electrochemical durability. Meanwhile, the HER performance also impressive, with an overpotential of about 87 mV at 10 mA cm−2. As a result, the hollow Ni@NiCo2O4 electrode as a bifunctional catalyst can achieve a current density of 10 mA cm −2 with a voltage of only 1.58 V, showing promise for high performance yet cheap electrocatalysts for the overall water splitting reactions. [ABSTRACT FROM AUTHOR]

Electrochemical splitting of water is an efficient way to produce clean energy for energy storage and conversion devices. Herein, 3D hierarchical NiCo2O4@NiO@Ni core/shell nanocone arrays (NAs) are reported on Ni foam for stable overall water splitting with high efficiency. The architecture and composition of the 3D catalysts are particularly tuned. The outstanding structural and component features of the as-prepared 3D catalysts are characterized by the vertically grown NiCo2O4 nanocone/NiO nanosheet core/shell structure and Ni decorated 3D-conductive networks, which largely prompt the catalytic performance. The hybrid catalyst with core/shell nanocone array structures exhibits superior bifuncational activities for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) with an overpotential of 240 and 120 mV at a current density of 10 mA cm−2, respectively. The Tafel slope of the optimal 3D electrode is about 43 and 58 mV dec−1 in an alkaline electrolyte for OER and HER, respectively. An alkaline electrolyzer constructed by two symmetric NiCo2O4@NiO@Ni electrodes delivers splendid activity toward overall water splitting with a current of 10 mA cm−2 at only ≈1.60 V and almost no deactivation after 10 h. This work provides a promising strategy to design ternary core/shell electrodes as high performance Janus catalysts for overall water splitting. [ABSTRACT FROM AUTHOR]

Bifunctional electrocatalyst is promising for the overall water splitting with high efficiency. Herein, inspired by the superior oxygen evolution reaction (OER) performance of transition metal oxide and remarkable hydrogen evolution reaction (HER) activity of transition metal phosphide, hierarchical NiCo2O4/Ni2P core-shell nanocone array on Ni foam is synthesized. The synergetic effect between the NiCo2O4 'core' and the Ni2P 'shell' results in dramatically enhanced catalytic performance. It shows higher activity and longer durability in both OER and HER than bare NiCo2O4 or Ni2P. The hierarchical NiCo2O4/Ni2P catalyst is capable of catalyzing OER with a low overpotential of 250 mV at 10 mA cm−2 in alkaline media. Moreover, it shows excellent catalytic activity for HER to achieve 10 mA cm−2 at a small overpotential of 45 mV. When the NiCo2O4/Ni2P is adopted as both anode and cathode in a two-electrode cell for overall water splitting, it only needs 1.59 V to reach a current density of 10 mA cm−2. Almost no decay is observed after the electrodes work for about 50 h. The newly developed electrocatalyst combines the satisfactory working stability with outstanding catalytic activity, which paves the way for exploring overall water splitting catalysts. [ABSTRACT FROM AUTHOR]

Aims. In this work, the main objectives were to investigate the clinical characteristics and bacterial spectrum present in open fractures contaminated by seawater. Methods. We conducted a retrospective cohort study and included all patients with open fractures from 1st January, 2012, to 31st December, 2015, in our hospital. Patients were grouped based on the presence of seawater contamination in wounds. We compared the infection rate, bacterial spectrum, and antibiotic resistance between the two groups. Results. We totally included 1337 cases of open fracture. Wounds from 107 cases (8.0%) were contaminated by seawater. The wound infection rate of seawater-contaminated group was significantly higher in patients with Gustilo-Anderson Type II and Type III open fractures. The bacterial spectrum from seawater-contaminated wounds was remarkably different from that of the remaining. Antibiotic sensitivity tests revealed that more than 90% of infecting pathogens in seawater-contaminated wounds were sensitive to levofloxacin and ciprofloxacin. Conclusion. Cephalosporin in combination with quinolone was recommended in the early-stage management of open fractures contaminated by seawater. [ABSTRACT FROM AUTHOR]

im: One major cause of hepatic sinusoidal obstruction syndrome (HSOS) is the consumption of products containing pyrrolizidine alkaloids (PA). As the use of herbal preparations has increased in China, so has the number of reports of HSOS induced by ingesting PA-containing herbs. The aim of the present study was to investigate the mechanisms by which prednisone and the related factors, transforming growth factor (TGF)-β1 and connective tissue growth factor (CTGF), prevent liver fibrosis and the pathogenesis of HSOS. Methods: A murine model of HSOS was created by oral gavage with Gynura segetum with or without prednisone for 30 days. Histological changes in liver tissue were evaluated by a scoring system in tissue slices subjected to hematoxylin-eosin and Masson trichrome staining. Hepatic expression of TGF-β1 and CTGF mRNA and protein was detected by immunohistochemistry, reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis. RT-PCR was also used to detect tumor necrosis factor (TNF)-α and nuclear factor (NF)-κBp65 mRNA expression. Activation of NF-κBp65 was detected by immunohistochemistry. Results: Intervention with prednisone diminished the symptoms of HSOS in mice treated with G. segetum. Prednisone treatment significantly inhibited expression of TGF-β1 and CTGF mRNA and protein ( P < 0.05), and inhibited expression of TNF-α and NF-κBp65 mRNA ( P < 0.05) in the liver tissue of HSOS mice. Conclusion: Prednisone suppresses the development of liver fibrosis in HSOS mice by inhibiting TGF-β1, CTGF, TNF-α and NF-κBp65 expression. [ABSTRACT FROM AUTHOR]