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In this paper, 4. 2% ytterbium-doped calcium niobium gallium garnet (Yb∶Ca3 (NbGa)5 O12) crystals with diameter of 2 inch (1 inch =2. 54 cm) were grown by Bridgman method. The obtained crystals were intact and free of visible defects. Crystal structure was determine by XRD, which reveals that the crystal belongs to the cubic crystal system with lattice parameters a = b = c =12. 493 Å. The crystals were oriented and cut to obtain some (420) plane wafers with dimensions of 10 mm ×10 mm ×1 mm. These wafers were double-side polished to obtain the final samples. The performance of the samples was characterized through X-ray diffraction, ultraviolet-visible spectrophotometer, and fluorescence spectroscope. The results show that the rocking curve of the crystal has a full width at half maximum (FWHM) of 43″, and the transmittance reaches 80% in the near-infrared wavelength range. At 935 nm, FWHM of the absorption peak is 47. 15 nm and absorption crosssection is 1. 53 ×10 -20 cm2. When excited with a 980 nm laser, an emission peak was observed at 1 031 nm, corresponding to the transition of Yb3 + from the excited state 2 F5/2 to the ground state 2 F7/2. [ABSTRACT FROM AUTHOR]

Objectives: Global navigation satellite system-interferometric reflectometry (GNSS-IR) technology has become one of the effective methods to retrieve tide levels by utilizing multipath information in signal-to-noise ratio (SNR) data. However, it is usually necessary to limit the elevation range, resulting in less usable data and insufficient time resolution. To solve the above problems, a preprocessing data quality control method is proposed. Methods: First, the significant difference between usable and unusable data is obtained through comparative analysis. Based on this difference, a GNSS-IR data quality control method is proposed to classify SNR data and screen out unusable data by data reconstruction and building a Transformer model. Second, appropriate data sets are selected to verify and evaluate the effectiveness and generalization ability of the method. Results: The results show that there are significant differences in amplitude characteristics between usable and unusable data, and the proportion of usable SNR data for 5°-30° elevation is significantly improved by the proposed method, thus extending the elevation range of usable data to 5°-30° at the inversion site. Conclusions: The proposed method significantly improves the amount of usable data and the time resolution of the GNSS-IR tide level retrieval method, which is of great significance for the application of GNSS-IR technology in real-time monitoring of tsunami and storm surge, as well as marine studies such as long-term sea level changes. Moreover, the method is a preprocessing data quality control method, which can identify and screen unusable data before tidal level retrieval, to break through the limitation that the post-processing method needs to accumulate SNR data for a long time. Therefore, it is better applicable to a scene where the tidal level changes dramatically in a short time, such as a tsunami. [ABSTRACT FROM AUTHOR]

To solve the problem of slow convergence and susceptibility to local optima in solving robot path planning problems using the standard whale optimization algorithm (WOA), an improved whale optimization algorithm (PSO - AWOA) with hybrid particle swarm algorithm and adaptive weights strategy is proposed. By introducing nonlinear inertia weight factors into the standard PSO and WOA algorithms and adaptively updating the weights during the population evolution, the global exploration ability and convergence speed are improved. Meanwhile, by introducing the PSO algorithm with strong optimization-seeking ability into the exploitation stage of the WOA algorithm, the new solution of iteration is guaranteed to be better than the original solution, which enhances the ability to jump out of the local optima. Finally, the PSO AWOA algorithm is applied to generate the optimal path for the robot in the grid map simulation environment. The results show that the proposed PSO - AWOA algorithm outperforms in terms of optimization accuracy and convergence speed by comparing the time consumption, planning path length, and the number of turning points of the algorithms given, which verifies the effectiveness of the improved algorithm. [ABSTRACT FROM AUTHOR]

Considering the existing visible-infrared image (RGB-T) semantic segmentation models have limitations in segmentation performance, a nested semantic segmentation network fusing deep difference features is proposed. Specifically, the encoding part and the decoding part of the network are connected by a multi-level dense intermediate path to form a nested structure, and encoder features at various levels achieve densely repeated utilization via multi-stage path while the multimodal deep feature enhances its semantic expressiveness by the feature differential fusion strategy. The comparison experiments show that the proposed network achieves an average accuracy of 65.8% and an average intersection over union of 54.7% on the MFNet dataset. Compared with other state-of-the-art RGB-T segmentation models, it has better segmentation ability. [ABSTRACT FROM AUTHOR]

Burn dressings have the functions of preventing wound infection, inhibiting inflammation, and promoting wound healing in the treatment of burns, especially in the treatment of refractory burns. Therefore, it is urgent to develop highly efficient burn dressings to treat burns. Burn and wound management is the core of treatment. This article studies the specific roles of different types of dressings in burn wound healing, and elaborates on the application of inorganic dressings containing a single metal element or nanotech-based dressings, as well as heterojunction structures, which provide new options for burn treatment. On this basis, the development direction of burn wound dressings is prospected. [ABSTRACT FROM AUTHOR]

BACKGROUND: Pneumatic tourniquet can reduce bleeding in operation area and provide clear surgical visual field. However, because of its many collateral injuries, scholars at home and abroad have more controversies on the application of tourniquet. OBJECTIVE: To investigate the clinical efficacy of optimized use of tourniquet in total knee arthroplasty. METHODS: Clinical data of 96 patients with osteoarthritis who underwent primary unilateral total knee arthroplasty at the People’s Hospital of Hebi from December 2016 to June 2018 were retrospectively analyzed. The patients were divided into two groups according to the strategy of tourniquet. The control group (n=56) was treated with tourniquet before osteotomy and removed after bone cement fixation. The observation group (n=40) used tourniquet only in bone cement fixation. The operation time, tourniquet usage time, intraoperative blood loss, postoperative blood loss, and incidence of complications were recorded. The Visual Analogue Scale score, Hospital for Special Surgery score, range of motion of the knee joint, swelling of the affected limb, quadriceps muscle strength recovery and surgical satisfaction at postoperative 3 days were evaluated and compared. RESULTS AND CONCLUSION: (1) There was no significant difference in the operation time and total blood loss between two groups (P > 0.05). The tourniquet usage time in the observation group was significantly shorter than that in the control group (P < 0.05). The intraoperative blood loss in the observation group was higher than that in the control group, and the postoperative blood loss and hidden blood loss in the observation group were lower than those in the control group (P < 0.05). (2) The postoperative Visual Analogue Scale score, range of motion of the knee joint, Hospital for Special Surgery score, the swelling rate of the affected limbs, straight leg raise to 45°, and postoperative satisfaction in the observation group were significantly higher than those in the control group (P < 0. 05). (3) The incidence of postoperative complications in both groups showed no significant difference (P > 0.05). (4) In summary, the optimized use of tourniquet can reduce postoperative pain, swelling and drainage, promote the recovery of muscle strength and joint function, improve the satisfaction of patients, and has no significant effect on the total blood loss of total knee arthroplasty, but it can increase the intraoperative blood loss. [ABSTRACT FROM AUTHOR]

For uniform flow in artificial channels with different rough walls, the Froude number Fr, bottom slope ratio i, Reynolds number Re, discharge Q and channel mean water depth h were used as parameters. Through hydraulic model tests, the influence of these factors to the coefficient of roughness was determined and the primary and secondary relationships and related relationships among various factors were analyzed. The results show that the ranking of the hydraulic elements that have a greater influence on the roughness is the Froude number Fr, the channel average depth h and the bottom slope ratio i and the roughness has no relationship with discharge and Reynolds number. [ABSTRACT FROM AUTHOR]

Agricultural efficient water saving technology develops very fast in Xinjiang, hut as the main water supply source, the fact that sediment concentration of surface water is high affecting the promotion of the technology. So, it's necessary to research the bed cleaning device which can treat sediment effectively and meet the requirements of drip irrigation and the investment is relatively lower. The water drip gravity sinking sand filter tank has better solved the above problems. In this paper, we took the gravity desilting and filter basin of river water drip irrigation as the research object and studied the effects of water-sediment separation by the physical experiment, which the settling basin was 25 m long and the lateral overflow weir is 5 m, 3 m and 2 m long. The results show that the total processing efficiency of sediment can reach more than 55% under the working condition of the structure and the optimal side weir length is 3 m. 'Hie imported maximum sediment concentration is about 1.5 kg/m3 which meet the pool water quality standard. [ABSTRACT FROM AUTHOR]

BACKGROUND: Tissue bank receives donated human tissues and organs and performs various corresponding processing, including storage and transportation for the purposes to repair and to reconstruct various clinical tissue defects. OBJECTIVE: To predict the development of tissue banks in China by sorting out the development history of medical tissue banks and introducing the development status of tissue banks. METHODS: The first author searched the literature data published up to October 2021 through databases such as CNKI, WanFang, VIP, and PubMed. The search terms were “tissue bank, tissue transplantation, tissue donation, allograft, bone allograft, skin allograft, vascular allograft, organ donation, Red Cross Society of China, regulation, standard” in Chinese and English. The final manuscript was complete based on information inquiry on the official website of the National Medical Drugs Administration of China, as well as access to a professional book, Allogeneic Tissue Transplantation and Tissue Bank, exchange interviews with tissue bank practitioners, and on-the-spot investigations. RESULTS AND CONCLUSION: Medical tissue banks in China started in the 1950s, and have gone through the development stages of small-scale hospital tissue bank, non-profit tissue bank, and large-scale enterprise tissue bank. In the 1990s, tissue banks with enterprise nature were established in succession, the development and application of allogeneic tissues as materials for tissue repair were gradually improved. Various materials including allogeneic bone, skin, tendon, nerve and other materials have obtained the third-class medical device registration certificate. After entering the 21st century, non-profit tissue banks have emerged. At this time, tissue banks are mainly composed of three types: hospital tissue banks, enterprise nature tissue banks and non-profit tissue banks. With the effective development of the work, the clinical use of tissue materials has also increased yearly, and allogeneic tissue repair materials have become indispensable biomaterials for tissue repair and reconstruction in clinical practice. In 2020, with the “Regulations on Human Organ Transplantation (Draft Amendment)” soliciting opinions from the public and the promulgation and implementation of the “Civil Code of the People’s Republic of China,” the development of tissue banks has ushered in opportunities and challenges. It is believed that under the continuous development of science and technology and humanities, medical tissue banks will have greater development. [ABSTRACT FROM AUTHOR]

Lakes (including artificial reservoirs) are important surface water resources, and they are also an important part of the earth surface system consisting of "mountains, waters, forests, fields, lakes, grassland and desert". Based on the lake survey data and long-term monitoring data collected by the Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences as well as other institutions, this paper systematically analyzed the overall status and long-term trends of the ecological and environmental changes of natural and artificial lakes in China, focused on the ecological and environmental status and changes of typical lakes in the five major lake zones in China and highlighted the protection effects and challenges facing the ecological environment of lakes in China. In the meantime, countermeasures and suggestions for policy-makers and are proposed to promote the protection and restoration of the ecology and environment of lakes in China, and to ensure the water safety and sustainable development of lakes and river basins. [ABSTRACT FROM AUTHOR]

Objective To investigate the expression of mTOR in TMJOA condylar cartilage of SD rats. Methods The model of TMJOA in SD rats was established by unilateral mastication，and the corresponding shamoperation group was established. TMJOA model was established by unilateral mastication.The right condyle was taken 2, 4 and 8 weeks after modeling. HE staining and safranine o-solid green staining were used for pathological examination； The expressions of Sox9 and mTOR were detected by immunohistochemical staining. Results　Hematoxylin-eosin (HE) staining and saffron o-green staining showed that the condylar cartilage of the control group had clear structure，smooth and intact surface，and the proteoglycans were evenly distributed. In the experimental group (TMD group)，obvious degenerative changes of condylar cartilage were observed over time (P < 0.05)，and the lesions were the highest in 4 W. Immunohistochemical staining showed that the expression level of Sox9 in the condylar cartilage of the experimental group decreased successively at 2 W (P < 0.01)，4 W (P < 0.05) and 8 W (P < 0.05)，and were lower than that of the control group. The expression level of mTOR decreased at 2 W (P < 0.05) and 4 W (P < 0.001)，but increased relatively at 8 W (P < 0.05) . Conclusion　With the progress of inflammation，mTOR in TMJOA condylar cartilage of SD rats shows a trend of early down-regulation and late upregulation, which plays a key role in transforming protective autophagy into destructive apoptosis. [ABSTRACT FROM AUTHOR]

To investigate the value of serum procalcitonin (PCT), C-reactive protein (CRP) / albumin (ALB) ratio combined with urinary leukocyte esterase (LEU) in predicting urinary tract infection after percutaneous nephrolithotomy (PCNL) in patients with complex renal calculi. 128 patients with complex kidney stones who were treated by PCNL in our hospital from March 2015 to June 2021 were selected as the observation object. They were followed up regularly after operation to count the situation of urinary tract infection. They were divided into urinary tract infection group and non urinary tract infection group according to whether postoperative urinary tract infection occurred. PCT level, LEU, CRP / ALB ratio and other clinical data were compared between the two groups. Multivariate Logistic regression was used to analyze the risk factors of postoperative urinary tract infection, draw the receiver operating characteristic (ROC) curve, and analyze the value of PCT, CRP / ALB ratio, LEU alone and combined detection in predicting postoperative urinary tract infection. The serum PCT and CRP / ALB in urinary tract infection group were higher than those in non urinary tract infection group (P<0.05). LEU was positive in the urinary tract infection group, but negative in the non urinary tract infection group. There were significant differences between the two groups in the history of previous urinary tract surgery, operation time,indwelling time of urinary catheter, length of hospital stay, preoperative urinary tract infection, stone load, use of > 3 antibiotics, renal dysfunction, intraoperative channel type and preoperative blood glucose level (P<0.05). Previous urinary tract surgery history, operation time ≥ 100 min, indwelling time of urinary catheter ≥ 7 d, preoperative urinary tract infection, stone load ≥ 1000 mm2, high preoperative blood glucose level and renal dysfunction were the risk factors of urinary tract infection after PCNL in patients with complex renal calculi (P<0.05). The area under the curve (AUC) of PCT, CRP / ALB and LEU alone in predicting urinary tract infection after PCNL were 0.712（0.476～0.944）, 0.686（0.436～0.931）and 0.836（0.753～0.918）respectively. The AUC of PCT, CRP / ALB and Leu combined in predicting urinary tract infection after PCNL was 0.879（0.785～0.972）, which were higher than those predicted by PCT, CRP / ALB and Leu alone. Conclusion There are many influencing factors of urinary tract infection in patients with complex renal calculi after PCNL, including indwelling time of urinary catheter, length of hospital stay, stone load, etc. in patients with urinary tract infection after PCNL, the ratio of PCT and CRP / ALB is high, and LEU is positive. These three may be used as biomarkers of urinary tract infection after PCNL [ABSTRACT FROM AUTHOR]

目的 探讨＂饬定法“单开门椎管扩大成形木治疗多节段脊婕型颈推病术后是否佩戴颈托的疗效差异。方法 选择2014年9月至2017年7月该科多节段脊髓型颈椎病60例，采用“铝钉法”C3~C7单开I1推管扩大成形木治疗，手术为同一组医生实施。术后随机将其分为改良组和对照组，各30例。改良组术后颈椎不佩戴颈托，麻醉清醒后笫2 天即指导患者颈椎康复锻炼；对照组3术后常规佩戴颈托3周后指导患者颈椎康复锻炼。记录比较两组术后3、6、12、18个月随访的日 本骨科协会评分标准(JOA)评分、颈椎活动度、颈椎曲度、轴性症状。结果 两组患者术后JOA评分均明显改善，但两组患者术后3、6、12、18个月的JOA评分比较，差异均无统计学意义(P>0.05)；两组患者术前颈椎活动度和颈椎曲度比较，差异均无统计学意义(P>0. 05)；改良组末次随访颈椎曲度和颈椎活动度均优于对照组，差异均有统计学意义(P<0.05)；改良组轴性症状发生率明显低于对照组，差异有统计学意义(P<0.05)。结论 ”铅钉法“单开门椎管扩大成形术治疗多节段脊髓型颈椎病术后不佩戴颈托进行早期康复是可行的，能有效降低轴性症状，改善颈椎活动度，提高患者舒适度，但对神经功能恢复改善无明显作用。 [ABSTRACT FROM AUTHOR]

Hg3 In2 Te6 (MIT for short) is a stable phase corresponding to x =0. 5 in the II-IV/III-IV compound semiconductor Hg(3-3x) In2x Te3. In this paper, the stability and doping efficiency of Au in MIT were systematically investigated using the firstprinciples method. The results show that Au-Te bonds has polar covalent bond characteristics similar to that of Hg-Te bonds in MIT, indicating that Au has certain doping stability in MIT. In addition, it is found that there are amphoteric doping properties of Au in MIT: Au exhibits acceptor properties in AuHg and AuIn systems, and the Au-5d electron orbital resonates with the Te-5p electron orbital at the top of the valence band and - 4 eV position, respectively, forming acceptor defect levels. While Au exhibits donor characteristics in AuTe and AuI systems, Au-5d resonates with Hg-6s and In-5s electron orbitals at the conduction band bottom, forming donor defect levels. It is worth noting that under Hg-rich conditions, there will be a self-compensation effect between AuI, AuTe and AuHg systems, and the Fermi level will be pinned at the top of valence band, while under Te-rich conditions, the self-compensation effect will be effectively eliminated. [ABSTRACT FROM AUTHOR]

In order to establish a fast, accurate and efficient evaluation method for the impact of shield construction on adjacent buildings, the principal strain based on angular distortion and lateral strain was selected as the evaluation index to assess the damage to the building. Numerical investigation was carried out to explore the interaction between the building and the ground, and the results showed that the bending stiffness and the axial stiffness had a significant influence on the angular deformation index of the building, while the horizontal strain index of the building was mainly affected by the axial stiffness. A calculation method of building deformation index considering the influence of the building was established, and DPI as a measure of the influence degree was introduced. A method for evaluating the influence of shield construction on adjacent buildings was presented, which considered the interaction between buildings and strata, and was convenient for engineering application. The results of the proposed evaluation method were in good agreement with the field observed data. [ABSTRACT FROM AUTHOR]

Feg()i nanoparticles were prepared by chemical co--precipitation method, and the particles were surface treated with citric acid and oleic acid. Through field transmission electron microscope, Fourier infrared spectrometer, UV-visible spectrophotometer test and four-ball friction and wear tester, the size and morphology, surface functional groups, dispersion stability and tribological properties of modified nanoparticles were evalua-ted respectively. Scanning electron microscope and optical microscope were used to analyze the morphology of wear scars. The modified nanoparticles are spherical and contain a small amount of square particles. Among them, the average particle size of the citric acid modified particles is (9.6 土().1 9) nm, and the average particle size of the particles modified by citric acid and oleic acid is 9.8i().1 6 nm. The infrared spectrum shows that the active agent is successfully coated on the surface of the particles. The absorbance of the magnetic fluid does not change much within 3() hours and tends to be stable, with good dispersion stability. Under a certain concentration of magnetic fluid lubrication, it exhibits excellent anti-friction and anti-wear properties. Among them, ().3% magnetic fluid has the best anti-friction and anti-wear performance. The friction coefficient is reduced by 22.68%, and the wear scar diameter is reduced by up to 13.7%. Through the synergy of the formation of adsorption film, deposition repair, micro-bearing and micro-cutting, a certain concentration of magnetic fluid can effectively improve the anti-wear and anti-wear properties of glycerin, and the type of surfactant has an impact on the friction performance of glycerin-based magnetic fluid. [ABSTRACT FROM AUTHOR]

Scientific and technological innovation plays key supporting and leading roles to achieve "carbon peaking and carbon neutrality" goals (referred to as "dual carbon"). It is necessary to make sustained efforts in the three aspects, namely energy structure adjustment, energy consumption, and carbon sequestration, and build a novel multi-energy-integrated energy production and utilization system based on hydrogen energy, energy storage, and methanol, in which the main lines are clean and efficient utilization of fossil energy, large-scale utilization and complementation of clean energy, low-carbon reconstruction of industrial processes, and intelligent multi-energy integration of building and transportation. In 2022, the Chinese Academy of Sciences has launched the scientific and technological action plan to support dual carbon goals. By implementing eight major actions including strategic research, cross-innovation of basic frontiers, breakthroughs in key technologies, comprehensive demonstration of new technologies and other scientific and technological innovation, deploying talent team building, international cooperation, improvement of innovation system capabilities, and popular science and dissemination actions, the action plan is to provide vigorous scientific and technological support for China's carbon peaking and carbon neutrality goals. [ABSTRACT FROM AUTHOR]

In this paper, nano-FeTiO3 powders with different Ferro titanate molar ratios were prepared by sintering in a reduction atmosphere. The samples were characterized by XRD, XI'S, BET, Zeta potentiometer and VSM. The adsorption of Congo red with different Ferrotitanate molar ratios was studied. According to the study, when FeTiO3 molar ratio was 1 : in the reduction atmosphere, the sample was pure FeTiO3 phase. When FeTiO3 ion ratio was 0.25 : 1 and 0.5 : 1, the sample phase was composed of FeTiO3 and titanium oxide. When FeTiO3, ratio was increased to 2: 1, a small amount of Fe3+C 0.1 and Fe3C were also found in the sample. In the sample, Fe coexisted in Fee2+ and Fe3+ forms, while titanium coexisted in Ti3+ and Ti1+ forms with oxygen vacancy. The dye adsorption performance study showed that the samples with a molar ratio of 0.5 : 1 had the best adsorption performance due to the large specific surface area and Zeta potential value, and the maximum equilibrium adsorption capacity was 128.7 mg/g. The adsorption process conformed to pseudo-second-order model. At the same time, the magnetic test shows that the sample had certain magnetism, so the dye could be re covered and reused by external magnetic field after adsorption. [ABSTRACT FROM AUTHOR]

BACKGROUND: A proper virus inactivation procedure of medical bio-derived tissue repair material is very important to reduce the risk of virus infection and ensure the safety in the therapeutic process. OBJECTIVE: To elaborate different virus inactivation methods of allogeneic and xenogeneic tissue repair materials. METHODS: PubMed, Elsevier, CNKI, and WanFang databases were searched for relevant articles using the keywords of “allogeneic, xenogeneic, viral inactivation, disinfection, tissue repair biomaterial” in English and Chinese, respectively. RESULTS AND CONCLUSION: Virus inactivation methods can damage the performance of biological materials to different extents. For example, heat inactivation may produce permanent damage to the performance of heat-sensitive materials; γ-ray irradiation may result in the loss of mechanical properties and biologically active substances; acid/alkali method may also destroy the properties and structure of some materials intolerant to acid and alkali corrosion; and some reagent residues such as ethylene oxide, peracetic acid, and hydrogen peroxide may produce irritation to the body and even cause carcinogenic and teratogenic substances. Therefore, in enterprises and research institutions, the virus-killing effect and severity of damage to the material performance should be considered when the virus inactivation process is selected, and the use of existing production processes to verify the virus inactivation is recommended as much as possible. [ABSTRACT FROM AUTHOR]