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Ammonium dinitramide (ADN), as a novel and environmentally friendly oxidizer, has strong hygroscopicity when exposed to high-humidity air, which seriously hinders its application in solid propellants. Modification of oxidizers by cocrystallization is an effective strategy to improve the hygroscopicity of energetic components. In this paper, the theoretical simulation of ADN/CL-20 cocrystals was developed via a directional hydrogen bonding design to establish a cocrystal with improved hygroscopicity. Intermolecular interaction analyses reveal that hydrogen bonds and van der Waals interactions synergistically lead to the formation of cocrystals. The ADN/CL-20 cocrystal was prepared experimentally by the spray drying self-assembly technique, and the corresponding thermal analysis and sensitivity properties were conducted to illustrate the thermal stability and high safety. Furthermore, the critical relative humidity (CRH) measurement was carried out to evaluate the hygroscopicity of the cocrystal, exhibiting a certain degree of antihygroscopic effect with a CRH of 65%. The hydrogen bonds formed between ADN and CL-20 saturate the ammonium ions of ADN, further preventing ADN from absorbing water molecules in the air. The ADN/CL-20 cocrystal has high specific impulse characteristics (Isp: 272.6 s). Accordingly, this work clearly demonstrates that the ADN/CL-20 cocrystal is expected to be used in a solid propellant to make up for the deficiency of the ADN oxidizer.
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PoDPBT, an O-benzoyltransferase belonging to the BAHD family, can catalyze the benzoylation of 8-debenzoylpaeoniflorin to paeoniflorin. PoDPBT is the first enzyme demonstrated to be involved in the modification stage of paeoniflorin biosynthesis. DFGGG, a new DFGWG-like motif, was revealed in the BAHD family. The transcriptome database provides a resource for further investigation of other enzyme genes involved in paeoniflorin biosynthesis.
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Paeonia , Paeonia/genética , Aciltransferases/genética , Monoterpenos , CatáliseRESUMO
We developed a digital optical phase locking loop (OPLL) with three advantages, including high precision of phase locking, high control bandwidth up to 2.8 MHz, and automatic laser locking strategy. Spaceborne laser interferometers will be used to measure tiny displacements caused by gravitational waves in millions of kilometers range. A slave laser will be heterodyne phase locked to the incoming weak light at the end of an arm, emitting a higher power light back to the other satellite to measure pathlength variations at the picometer level. Such accuracy requires extremely precise OPLL. We report an experiment to demonstrate a digital OPLL that can automatically lock two independent free-running Nd:YAG lasers with residual phase error below 1mrad/Hz above 0.01 Hz, which is the best performance recorded for digital servos, to our knowledge. Such performance tested under a normal laboratory environment will be highly improved in a vacuum environment with temperature and vibration well controlled. Both the digital OPLL and the automatic strategy were implemented on a field programmable gate array that could be potentially used for future gravitational-wave detection. Our experiment might change the thinking of scientists who study phasemeters of gravitational-wave detection because we are aware that the digital phase locking loop used for "optical phase tracking" is differently designed from "optical phase locking."
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Lithium-sulfur (Li-S) battery is one of the most promising next-generation rechargeable batteries. Lots of fundamental research has been done for the problems during cycling like capacity fading and columbic efficiency reducing owing to severe diffusion and migration of polysulfide intermediates. In the early stage, a wide variety of carbon materials are used as host materials for sulfur to enhance electrical conductivity and adsorb soluble polysulfides. Beyond carbon materials, metal based polar compounds are introduced as host materials for sulfur because of their strong catalytic activity and adsorption ability to suppress the shuttle effect. In addition, relatively high density of metal compounds is helpful for increasing volumetric energy density of Li-S batteries. This review focuses on crystalline multi-metal compounds as host materials in sulfur cathodes. The multi-metal compounds involve not only transition metal composite oxides with specific crystalline structures, binary metal chalcogenides, double or complex salts, but also the metal compounds doped or partially substituted by other metal ions. Generally, for the multi-metal compounds, microstructure and morphologies in micro-nano scale are very significant for mass transfer in electrodes; moreover, adsorption and catalytic ability for polysulfides make fast kinetics in the electrode processes.
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Layered lead-halide organic-inorganic hybrid perovskites have shown great application prospects in photovoltaics and optoelectronics because of their diverse structural assemblies and richness in physical properties. In this report, a rare corrugated layer lead bromide hybrid perovskite of (demethyltropinone)4Pb3Br10 was discovered undergoing a high-temperature reversible phase transition at 410 K, which is induced by the order-disorder transition of organic cation response to the variation of external temperature. The title compound exhibits prominent switchable dielectric behavior, coupled with semiconducting property and brilliant orange fluorescence under UV excitation. The integrated multifunction ability indicates the emergence of new promising materials and provides new fertile ground to discover more potentially useful materials.
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Hydraulic support leg pressure serves as a crucial indicator for assessing work face support quality. Current evaluation methods for support quality primarily concentrate on static analyses-like inadequate initial support force, pressure overrun, and uneven bracket force-while neglecting dynamic column pressure changes. This paper introduces a model for assessing hydraulic support quality using deep learning techniques. Real-time data is preprocessed into a spatio-temporal pressure sub-matrix sample, which is then inputted into the model. This process assesses the support quality type and characterizes its dynamic evolution within the area. The model facilitates the identification of dynamic support quality effects in the working face area, aiding operators in making targeted adjustments to hydraulic support status. Experimental results revealed that the optimized LeNet-5 network-adjusting parameters like convolutional layer count, kernel size, and ReLU activation function-achieved the highest classification accuracy of 85.25 % for support quality, surpassed other networks. Furthermore, the improved LeNet-5 network outperformed other networks in both F1 score and recall. Additionally, the improved LeNet-5 network achieved faster convergence to the optimal solution, accelerated training speed. This highlighted its advantages in evaluating the spatio-temporal support quality of hydraulic supports in smart mining operations.
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Hydrogen peroxide (H2O2) is a signaling molecule that has the capacity to control a variety of biological processes in organisms. Cancer cells release more H2O2 during abnormal tumor growth. There has been a considerable amount of interest in utilizing H2O2 as a biomarker for the diagnosis of cancer tissue. In this study, an electrochemical sensor for H2O2 was constructed based on 3D reduced graphene oxide (rGO), MXene (Ti3C2), and multi-walled carbon nanotubes (MWCNTs) composite. Three-dimensional (3D) rGO-Ti3C2-MWCNTs sensor showed good linearity for H2O2 in the ranges of 1-60 µM and 60 µM-9.77 mM at a working potential of -0.25 V, with sensitivities of 235.2 µA mM-1 cm-2 and 103.8 µA mM-1 cm-2, respectively, and a detection limit of 0.3 µM (S/N = 3). The sensor exhibited long-term stability, good repeatability, and outstanding immunity to interference. In addition, the modified electrode was employed to detect real-time H2O2 release from cancer cells and cancer tissue ex vivo.
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Técnicas Biossensoriais , Eletrodos , Grafite , Peróxido de Hidrogênio , Nanotubos de Carbono , Neoplasias , Nanotubos de Carbono/química , Grafite/química , Humanos , Neoplasias/diagnóstico , Técnicas Eletroquímicas , Limite de DetecçãoRESUMO
OBJECTIVE: To explore preemptive analgesic effect of preoperative intramural tramadol injection in percutaneous kyphoplasty (PKP) of vertebrae following local anesthesia. METHODS: From August 2019 to June 2021, 118 patients with thoraco lumbar osteoporotic fractures were treated and divided into observation group and control group, with 59 patients in each gruop. In observation group, there were 26 males and 33 females, aged from 57 to 80 years old with an average of (67.69±4.75)years old;14 patients on T11, 12 patients on T12, 18 patients on L1, 15 patients on L2;tramadol with 100 mg was injected intramuscularly half an hour before surgery in observation group. In control group, there were 24 males and 35 females, aged from 55 to 77 years old with an average of (68.00±4.43) years old;19 patients on T11, 11 patients on T12, 17patients on L1, 12 patients on L2;the same amount of normal saline was injected intramuscularly in control group. Observation indicators included operation time, intraoperative bleeding, visual analogue scale (VAS) evaluation and recording of preoperative (T0), intraoperative puncture(T1), and working cannula placement (T2) between two groups of patients, at the time of balloon dilation (T3), when the bone cement was injected into the vertebral body (T4), 2 hours after the operation (T5), and the pain degree at the time of discharge(T6);adverse reactions such as dizziness, nausea and vomiting were observed and recorded;the record the patient's acceptance of repeat PKP surgery. RESULTS: All patients were successfully completed PKP via bilateral pedicle approach, and no intravenous sedative and analgesic drugs were used during the operation. There was no significant difference in preoperative general data and VAS(T0) between two groups (P>0.05). There was no significant difference in operation time and intraoperative blood loss between the two groups (P>0.05). VAS of T1, T2, T3, T4 and T5 in observation group were all lower than those in control group(P<0.05), and there was no significant difference in T6 VAS (P>0.05). T6 VAS between two groups were significantly lower than those of T0, and the difference was statistically significant (P<0.05). There was no significant difference in incidence of total adverse reactions between two groups (P>0.05). There was a statistically significant difference in the acceptance of repeat PKP surgery (P<0.05). CONCLUSION: Half an hour before operation, intramuscular injection of tramadol has a clear preemptive analgesic effect for PKP of single-segment thoracolumbar osteoporotic fracture vertebral body under local anesthesia, which could increase the comfort of patients during operation and 2 hours after operation, and improve patients satisfaction with surgery.
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Anestesia Local , Cifoplastia , Vértebras Lombares , Fraturas por Osteoporose , Vértebras Torácicas , Tramadol , Humanos , Feminino , Masculino , Idoso , Tramadol/administração & dosagem , Pessoa de Meia-Idade , Cifoplastia/métodos , Vértebras Torácicas/cirurgia , Vértebras Torácicas/lesões , Fraturas por Osteoporose/cirurgia , Vértebras Lombares/cirurgia , Anestesia Local/métodos , Idoso de 80 Anos ou mais , Analgesia/métodos , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Fraturas da Coluna Vertebral/cirurgia , Analgésicos Opioides/administração & dosagemRESUMO
BACKGROUND AND OBJECTIVE: Patients on parenteral nutrition (PN) are at high risk of both liver and pancreatic injury. More efforts were focused on liver, however, limited data is available to evaluate the effects of PN on pancreas. Thus, we performed a retrospective observational study to evaluate the association between PN and pancreatic injury in Chinese adult patients. METHODS: Adult patients (18-80 years), who received PN for a week or longer, and with repeated measurements of pancreatic enzymes, were included in the analysis. Pancreatic injury was confirmed by serum level of pancreatic amylase (P-AMYwas 53 U/L or higher) or lipase (LP was 63 U/L or higher), which were evaluated at baseline and following every week during PN duration. Age, sex, body weight, height, diagnosis of diseases, history of diseases, surgery, white blood cell, c-reactive protein, liver and renal function, fasting blood glucose, lipid profile, and daily energy supplied by PN and enteral nutrition were abstracted from medical records. RESULTS: A total number of 190 adult patients (125 men, 65 women) were included in the study. The average age and BMI were 61.8 ± 13.0 years and 21.7±3.3 kg/m2, while medium serum level of P-AMY and LP were 29.0 U/L (quartile range: 18.0, 47.0) and 33.0 U/L (quartile range: 19.0, 58.0), respectively at baseline. The median duration of PN was 15 days (quartile range: 11.0, 21.0). The prevalence of pancreatic injury was 42.1% (80/190) while it was 28.4% (54/190), 43.3% (77/178), 47.8% (44/92) after one-, two-, and three-week or longer PN adminstration. The proportion of daily energy supplement by PN (OR = 3.77, 95%CI: 1.87, 7.61) and history of infection were positively (OR = 3.00, 95%CI: 1.23, 7.36), while disease history for diabetes mellitus (OR = 0.38, 95%CI: 0.15, 0.98) and cancer (OR = 0.46, 95%CI: 0.23, 0.95), were negetively associated with pancreatic injury. Total bile acids were associated with the increment of P-AMY (beta = 0.98, 95%CI: 0.39, 1.56) and LP (beta = 2.55, 95%CI: 0.98, 4.12) by multi-variate linear regression. CONCLUSION: PN was associated with pancreatic injury, as demonstrated by the increase of both serum P-AMY and LP.
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The significant Tc enhancement of 110 K in [N-fluoromethyldabconium] triiodide lead caused by the promising design of H/F substitution is the first and unprecedented, opening up an applicable and universal strategy to effectively regulate the Tc working temperature in phase transition materials.
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OBJECTIVE: To compare the clinical and radiological outcome between the modified Broström repair with augmentation using suture tape (MBA) and the modified Broström repair (MB) for patients with chronic lateral ankle instability. METHODS: A retrospective study was performed in Ningbo No. 6 Hospital. The study included 53 patients who underwent surgical treatment from March 2014 to July 2016 and were followed for 2 years. A total of 25 patients underwent modified Broström repair with augmentation using suture tape, and 28 patients were treated with modified Broström repair. Patients were evaluated using the American Orthopedic Foot and Ankle Scale (AOFAS) hindfoot scale, the Foot and Ankle Ability Measure (FAAM) score, range of motion (ROM), and the visual analogue scale (VAS). The talar tilt angle (TTA) and anterior talar translation (ATT) were used to evaluate the mechanical stability. All radiological outcomes were measured by two orthopaedic surgeons, with the measurements repeated 3 days later. RESULTS: The mean age of the patients was 26.6 ± 17.8 years in the MBA group and 28.1 ± 19.4 years in the MB group, and no statistical difference in preoperative data was found between two groups. There were significant differences before and after the operation within the groups. Both groups achieved satisfactory outcomes, and significant improvements (VAS, FAAM, AOFAS, TTA, and ATT) were observed between the 1-year follow-up and final follow-up (P < 0.05). The MBA group showed significant improvement in the FAAM Sport (87.1 ± 5.4 vs 78.2 ± 12.0, P = 0.001) and total scores (93.1 ± 2.3 vs 90.5 ± 5.1, P = 0.027) at the final follow-up compared with the MB group, and for the other outcomes, there were no significant differences between the two groups. CONCLUSION: The modified Broström repair with augmentation using suture tap for chronic lateral ankle instability achieves a better outcome; however, further research is necessary.
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Articulação do Tornozelo/cirurgia , Instabilidade Articular/cirurgia , Ligamentos Laterais do Tornozelo/cirurgia , Procedimentos Ortopédicos/instrumentação , Fita Cirúrgica , Adolescente , Adulto , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/fisiopatologia , Avaliação da Deficiência , Humanos , Instabilidade Articular/diagnóstico por imagem , Instabilidade Articular/fisiopatologia , Ligamentos Laterais do Tornozelo/diagnóstico por imagem , Ligamentos Laterais do Tornozelo/fisiopatologia , Pessoa de Meia-Idade , Medição da Dor , Radiografia , Amplitude de Movimento Articular , Estudos Retrospectivos , Adulto JovemRESUMO
The qualitative analysis for by-products in the course of disinfection of the raw water and the effluent of GAC in Beijing Tiancuishan Drinking Water Treamtment Plant by potassium monopersulfate compound powder was determined. Halogen disinfection by-products during disinfection process by potassium monopersulfate compound powder was evaluated in a bench scale by comparing with chlorine disinfection process, and the genotoxicity evaluation of potassium monopersulfate compound powder and chlorine disinfection processes was also conducted by umu-test. The results showed that there were small changes in the organic pollutant components of water samples after disinfection by potassium monopersulfate compound powder, while some new halogen disinfection by-products were generated. Disinfection with potassium monopersulfate compound powder generated much less trihalomethanes (THMs) and haloacetic acids (HAAs) than chlorination disinfection. Moreover, the results of umu test indicated that the raw water and the effluent of GAC presented lower genotoxicity after potassium monopersulfate compound powder disinfection than chlorine disinfection. However, there was a risk for safety at a high level of organic matters and disinfectant dosage during potassium monopersulfate compound powder disinfection process.
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Desinfetantes/química , Água Potável/química , Compostos de Potássio/química , Sulfatos/química , Poluentes Químicos da Água/química , Purificação da Água , Pequim , Cloro/química , Desinfecção , Testes de Mutagenicidade , Trialometanos/químicaRESUMO
OBJECTIVE: To investigate the association of the expressions of Th1 cytokines in gastric cancer tissue and the prognosis of patients with gastric cancer after radical resection. METHODS: Fifty-eight patients with gastric cancer treated at the Zhongshan Hospital of Fudan University were retrospectively analyzed. The expressions of Th1 cytokines mRNA were detected in tumor tissues by real-time polymerase chain reaction(RT-PCR) method in Th1 cells including TRAV10, IRF1, TBX21, CD3Z, GZMB, GATA3, and IFNG. Association of Th1 cytokines mRNA expressions and prognosis was evaluated. RESULTS: The median follow up was 42.5(1-64) months. The 1-year survival rate was 84.5% and the 3-year survival rate was 72.4%. Univariate Cox regression analysis showed that lymph node metastasis, distant metastasis, TNM staging, lymphovascular invasion, GNLY mRNA expression, and the overall expression level of the 8 types of Th1 cells were associated with the prognosis of patients with gastric cancer(all P<0.05). The 3-year survival was 86.2% in patients with increased expression of mRNA and 58.6% in those with decreased expression. The 3-year survival was 79.6% in patients with any increase in the 8 Th1 cytokines and 33.3% in those with consistent downregulation of the 8 cytokines. Multivariate Cox analysis showed that lymph node metastasis and the overall expression level of 8 Th1 cytokines were independent risk factors associated with the prognosis of patients with gastric cancer in this cohort(both P<0.05). CONCLUSIONS: The mRNA expression of GNLY is associated with the prognosis of patients with gastric cancer but is not an independent risk factor. The combination of mRNA expressions of the eight cytokines is an independent prognostic factor.