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NO3RR synthesis of ammonia is a complex eight-electron reaction involving multiple steps and intermediates, in which NO3- adsorption and NH3 desorption are crucial. The Cu-based high entropy quinary alloy catalyst has good surface adsorption and desorption ability for the reduction of nitric acid to ammonia. Here, the catalytic sites were coordinated by constructing CuNiCoZnMn alloys to adjust the electronic structure of the catalytic sites to facilitate the reaction of the substrate and thus optimize the whole reaction path. Based on the ternary alloy CuNiCo, the introduction of the Zn element continues to reduce the desorption energy barrier, and the introduction of the Mn element continues to enhance the initial adsorption energy so that the target product can be quickly held and released to accelerate the production of ammonia. The NH3 yield and Faraday efficiency obtained for the quinary CuNiCoZnMn alloy catalyst reached 723.7 µmol h-1 cm-2 and 96.6%, respectively, at -0.35 V vs RHE potential. The density functional theory calculations showed that the quinary CuNiCoZnMn alloy (NO3- to *NO3-) initial adsorption-free energy change and (*NH3 to NH3) NH3 desorption-free energy change are -2.50, 0.072 eV, respectively, which are significantly better than those of the ternary CuNiC and quaternary CuNiCoZn of -2.02, 0.544 eV and -1.97, 0.217 eV.
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BACKGROUND: Fractures of hands and feet are common in children, but relevant epidemiological studies are currently lacking. We aim to study the epidemiological characteristics of hand and foot fractures and growth plate injuries in children and provide a theoretical basis for their prevention, diagnosis, and treatment. METHODS: We retrospectively analyzed the data of children with hand and foot fractures who were hospitalized at Shenzhen Children's Hospital between July 2015 and December 2020. Data on demographic characteristics, fracture site, treatment method, etiology of injury, and accompanying injuries were collected. The children were divided into four age groups: infants, preschool children, school children, and adolescents. The fracture sites were classified as first-level (the first-fifth finger/toe, metacarpal, metatarsal, carpal, and tarsal) and second-level (the first-fifth: proximal phalanx, middle phalanx, distal phalanx, metacarpal, and metatarsal) sites. The changing trends in fracture locations and injury causes among children in each age group were analyzed. RESULTS: Overall, 1301 children (1561 fractures; 835 boys and 466 girls) were included. The largest number of fractures occurred in preschool children (n = 549, 42.20%), with the distal phalanx of the third finger being the most common site (n = 73, 15.57%). The number of fractures in adolescents was the lowest (n = 158, 12.14%), and the most common fracture site was the proximal phalanx of the fifth finger (n = 45, 29.61%). Of the 1561 fractures, 1143 occurred in the hands and 418 in the feet. The most and least common first-level fracture sites among hand fractures were the fifth (n = 300, 26.25%) and first (n = 138, 12.07%) fingers, respectively. The most and least common first-level foot fracture locations were the first (n = 83, 19.86%) and fourth (n = 26, 6.22%) toes, respectively. The most common first-level and second level etiologies were life related injuries (n = 1128, 86.70%) and clipping injuries (n = 428, 32.90%), respectively. The incidence of sports injuries gradually increased with age, accounting for the highest proportion in adolescents (26.58%). Hand and foot fractures had many accompanying injuries, with the top three being nail bed injuries (570 cases, 36.52%), growth plate injuries (296 cases, 18.96%), and distal severed fracture (167 cases, 10.70%). Among the 296 growth plate injuries, 246 occurred on the hands and 50 on the feet. CONCLUSIONS: In contrast to previous epidemiological studies on pediatric hand and foot fractures, we mapped the locations of these fractures, including proximal, shaft, distal, and epiphyseal plate injuries. We analyzed the changing trends in fracture sites and injury etiologies with age. Hand and foot fractures have many accompanying injuries that require attention during diagnosis and treatment. Doctors should formulate accident protection measures for children of different ages, strengthen safety education, and reduce the occurrence of accidental injuries.
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Traumatismos de los Pies , Fracturas Óseas , Traumatismos de la Mano , Huesos del Metacarpo , Fracturas de Salter-Harris , Masculino , Preescolar , Lactante , Femenino , Adolescente , Niño , Humanos , Estudios Retrospectivos , Fracturas de Salter-Harris/complicaciones , Fracturas Óseas/epidemiología , Fracturas Óseas/etiología , Fracturas Óseas/diagnóstico , Traumatismos de la Mano/epidemiología , Traumatismos de la Mano/etiología , Traumatismos de la Mano/terapia , Huesos del Metacarpo/lesiones , Traumatismos de los Pies/epidemiología , Traumatismos de los Pies/etiología , Traumatismos de los Pies/terapiaRESUMEN
The deep integration of the digital economy and high-quality energy development is a vital breakthrough in promoting the digital transformation and upgrading of energy, and it is also a critical path to achieving green and low-carbon development. However, the degree of integration of the two has yet to be discovered. This article measures the coupling coordination degree of the digital economy and high-quality energy development using panel data from 30 provinces in China from 2013 to 2020, explores the spatiotemporal evolution characteristics of the coupling coordination degree, and further analyzes the driving factors of the coupling coordination degree. The results show that:(1) The coupling coordination degree shows an upward trend, but there are apparent gradient differences and spatial non-equilibrium features in the coupling coordination degree among provinces. (2) The coupling coordination degree shows a "parabolic" spatial trend of "high east and low west" in the east-west direction and an "inverted U-shaped" spatial trend in the north-south direction. (3) The center of gravity of the coupling coordination degree moves to the southwest, clustering in the northeast-southwest direction and showing a spreading trend in the southeast-northwest direction. (4) The coupling coordination degree has a significant positive spatial correlation, and the cold-hot spot gradually develops into a distribution pattern with the Yangtze River Delta in China as the agglomeration center. (5) Economic development, industrial structure, government behavior, environmental regulation, urbanization, technological innovation, and external openness significantly impact the coupling coordination degree. In addition, economic development and human capital have a positive spatial spillover effect on the coupling coordination degree. Urbanization level and technological innovation have a negative spatial spillover effect on the coupling coordination degree. Accordingly, to promote the coupling and interaction between the digital economy and high-quality energy development, the government should take effective measures in optimizing the industrial structure, scientifically promoting the urbanization process, and enhancing the scientific and technological innovation capacity.
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OBJECTIVE: To explore the value of ultrasonography in the diagnosis and treatment of Langerhans cell histiocytosis (LCH) in children. METHOD: The clinical and imaging features of 55 children with pathologically confirmed LCH were retrospectively analyzed. RESULTS: Thirteen patients had bone LCH and 42 had multisystem LCH. Among the 13 cases of bone LCH, 8 cases involving the skull and 2 involving the scapula were characterized by osteolytic bone destruction, 1 case involving the clavicle and 1 involving the iliac bone showed multiple irregular bone destruction, and 1 case involving the tibia showed local hypoechoic cortical bone. Soft tissue echo filling was present in the local areas of bone destruction. Among the 42 cases of multisystem LCH, 33 involved the bone, 35 showed an enlarged liver, 15 involved the spleen, 2 involved the pancreas, 3 involved the lung, 3 involved the thymus, and 21 affected the lymph nodes in different regions. CONCLUSIONS: Ultrasonography of the flat bones in children with LCH mainly showed punched-out osteolytic bone destruction. Long bone lesions were characterized by fan shell changes in the endosteum of long bones, and some also showed bone destruction. Multisystem LCH can affect almost any organ. Ultrasonography is important for early diagnosis.
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Enfermedades Óseas , Histiocitosis de Células de Langerhans , Enfermedades Óseas/diagnóstico por imagen , Niño , Histiocitosis de Células de Langerhans/diagnóstico por imagen , Histiocitosis de Células de Langerhans/patología , Humanos , Ganglios Linfáticos/patología , Estudios Retrospectivos , CráneoRESUMEN
CRISPR/Cas technologies have revolutionized the ability to redesign genomic information and tailor endogenous gene expression. Nevertheless, the discovery and development of new CRISPR/Cas systems has resulted in a lack of clarity surrounding the relative efficacies among these technologies in human cells. This deficit makes the optimal selection of CRISPR/Cas technologies in human cells unnecessarily challenging, which in turn hampers their adoption, and thus ultimately limits their utility. Here, we designed a series of endogenous testbed systems to methodically quantify and compare the genome editing, CRISPRi, and CRISPRa capabilities among 10 different natural and engineered Cas protein variants spanning Type II and Type V CRISPR/Cas families. We show that although all Cas protein variants are capable of genome editing and transcriptional control in human cells, hierarchies exist, particularly for genome editing and CRISPRa applications, wherein Cas9 ≥ Cas12a > Cas12e/Cas12j. Our findings also highlight the utility of our modular testbed platforms to rapidly and systematically quantify the functionality of practically any natural or engineered genomic-targeting Cas protein in human cells.
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Sistemas CRISPR-Cas , Edición Génica , Humanos , Edición Génica/métodos , Sistemas CRISPR-Cas/genética , Genoma , GenómicaRESUMEN
It is an ideal way to use triboelectric nanogenerators (TENGs) to capture energy from the environment for the degradation of organic contaminants in water as a zero-carbon pathway. However, there is an urgent need to further develop TENGs with a simple structure and high output power. Herein, a novel TENG with a vortex-like flexible self-recovery blades of inner stator (denoted as VFR-TENG) is designed and manufactured with the assistance of a fused deposition modeling 3D printing technology. With the rotation of the outer rotor, a facile rotating contact-separation mode is achieved by the alternating arrangement of the flexible self-recovery blades. The contact tightness of the friction layer, a key factor for the transfer of charge density, can be easily adjusted by the thickness and arrangement style of the flexible self-recovery blades. The regulation of material elasticity and rotational frequency on the output characteristics is further investigated based on the special flexible structure. The VFR-TENG exhibits an instantaneous short-circuit current of 350 µA, an open-circuit voltage of 650 V, a transferred charge of 1.1 µC, and an optimum output power density of 4.4 W·m-2. This high-performance VFR-TENG is used for electrochemical degradation systems, which achieves excellent degradation efficiencies of 88.9, 91.7, and 94.1% for methylene blue, methyl orange, and malachite green within 150 min, respectively. This work provides a new idea for the design of flexible self-recovery contact-separation TENGs, which is of great inspiration for the exploitation of TENGs with both the high peak current and high-frequency characteristics for efficient water treatment.
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A persistent ultrasound-assisted hydrothermal method has been developed to prepare cobalt oxide incorporated nitrogen-doped graphene (Co3O4/N-GO) hybrids. The electrochemical behaviors and catalytic activity of the prepared hybrids have been systematically investigated as cathode materials for Al-air battery. The results show that ultrasonication can promote the yield ratio of Co3O4 from 63.1% to 70.6%. The prepared Co3O4/N-GO hybrid with ultrasonication exhibits better ORR activity over that without ultrasonication. The assembled Al-air battery using the ultrasonicated Co3O4/N-GO hybrid exhibited an average working voltage of 1.02 V in 4 M KOH electrolyte at 60 mAâcm-2, approximately 60 mV higher than that using hybrid without ultrasonication. This should be attributed to large number density of fine Co3O4 particles growing on the dispersed GO sheets under the persistent ultrasonication. The related ultrasonic mechanism has been discussed in details.
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In this paper, cyclic voltammetry and square wave voltammetry are applied to characterize the cathode processes of neodymium ions on a W electrode in LiF-NdF3 melts with or without the metal Nd. The results indicate that neodymium ions in the LiF-NdF3 (2 wt%) melt are reduced in two steps, i.e. Nd(3+) â Nd(2+) and Nd(2+) â Nd(0), corresponding to starting reduction potentials of 0.35 V vs. Li(+)/Li and 0.1 V vs. Li(+)/Li, respectively. The Nd(3+) â Nd(2+) process is controlled by mass transfer and the Nd(2+) â Nd(0) process is controlled by both an interfacial step and mass transfer. But in the LiF-NdF3 melt with excess metal Nd equilibrium, the kinetics of the above two processes are controlled by mass transfer. After potentiostatic electrolysis at 0.35 V in the LiF-NdF3-Nd2O3 melt NdF2 is formed on the Mo cathode, and metallic Nd is obtained by potentiostatic electrolysis at 0.1 V in the LiF-NdF3-Nd2O3-Nd melt, which validates the above electrochemical reduction results.
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In the traditional view, muscle atrophy and interstitial fibrosis were regarded as the basic pathological features of congenital muscular torticollis (CMT). But in the ultrastructure study, the mesenchyme-like cells, myoblasts, myofibroblasts, and fibroblasts were found in the proliferation of interstitium of CMT. To investigate the characteristics of pathological features and the mechanisms of muscle atrophy in CMT, we retrospectively reviewed the medical records of 185 CMT patients from July 2009 to July 2011 in Shenzhen Children's Hospital in China and performed pathological studies. According to age, the 185 CMT patients were divided into 4 groups. All resected surgical specimens were processed for hematoxylin and eosin staining and Masson trichromic staining. Sudan III staining was used for frozen sections, whereas immunohistochemical staining for S-100, calpain-1, ubiquitin, and 20S proteasome was carried out on 40 CMT specimens. Eight adductor muscle specimens from 8 patients with development dysplasia of the hip were taken as control group in the immunohistochemical staining. By Masson trichromic staining, the differences in the percent area of fibrous tissue in each CMT groups were significant. In Sudan III staining and immunostaining for S-100, adipocyte hyperplasia was the pathological feature of CMT. Moreover, compared with controls, most atrophic muscle fibers in CMT specimens were found to show strong immunoreactivity for calpain-1, ubiquitin, and 20S proteasome. With increasing age, fibrosis peaked at both sides and it was low in middle age group. Adipocytes increased with age. The characteristics of pathological features in CMT are changeable with age. The calpain and the ubiquitin-proteasome system may play a role in muscle atrophy of CMT. In the CMT, adipogenesis, fibrogenesis, and myogenesis may be the results of mesenchyme-like cells in SCM (sternocleidomastoid muscle). In conclusion, the present study furthermore supports maldevelopment of the fetal SCM theory for etiology of CMT.
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Adipogénesis , Atrofia Muscular/etiología , Atrofia Muscular/patología , Músculos del Cuello/patología , Tortícolis/congénito , Adolescente , Niño , Preescolar , Femenino , Fibrosis/etiología , Humanos , Inmunohistoquímica , Lactante , Masculino , Estudios Retrospectivos , Tortícolis/complicaciones , Tortícolis/patologíaRESUMEN
In a greenhouse study, Cyperus alternifolius, Coleus blumei and Jasminum sambac were cultured in a floating phytoremediation system with plantation cups inserted into a polyfoam plate that floated in the upper part of a tank filled with 100 L domestic wastewater. The contents of chemical oxygen demand (CODCr), total P (T-P), total N (T-N), soluble P(S-P), ammonia-nitrogen (NH4+ -N) and nitrate-nitrogen (NO3- -N) in the domestic wastewater were tested during the growth of these three plants. The results showed that Cyperus alternifolius and Coleus blumei could grow well in the floating phytoremediation system, their dry weight being 285.8% and 371.4% of the initial weight of planting, respectively, but Jasminum sambac could not grow well, being 125.0% of the initial weight of planting. The removal rate of TN by these 3 plants was 68.0%, 62.0% and 45.0%, and that of NO3- -N, CODCr and TP was 98.0%, 80.0% and 92.0%, 78.0%, 66.0% and 55.0%, and 90.6%, 90.5% and 88.0% respectively. Cyperus alternifolius and Coleus blumei had good effects on the removal of pollutants in the floating phytoremediation system.