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With the rapid expansion of the scale of nuclear energy, the proper treatment of radioactive waste generated by the nuclear industry has become one of the most important issues for the further development of nuclear energy. Cyclodextrin, as a kind of cyclic oligosaccharide composed of several glucopyranose units, has a good prospect of application in the field of radioactive ions adsorption and separation, because of its special molecular structure of internal hydrophobicity and external hydrophilicity. However, due to the presence of a large number of hydroxyl groups in the cyclodextrin molecules, they are easily soluble in water. Generally, the solidification of cyclodextrins to insoluble solids is always needed before being used as adsorption materials. Depending on the different methods of " solidification", cyclodextrin based adsorbent materials can be divided into three types: loaded cyclodextrin materials, cyclodextrin polymer materials, and cyclodextrin inclusion complex materials. The synthesis and application research advances of the three types of cyclodextrin adsorbent materials in radioactive ion adsorption and separation are summarized, the related adsorption mechanisms are discussed. Besides, the perspectives of the cyclodextrin based adsorbents in the field of radioactive ion adsorption are presented. [ABSTRACT FROM AUTHOR]

[Objectives] To accomplish the design of a two-stage dual-rotor opposed centrifugal compressor for a small gas turbine,[Methods] the compressor is subject to aerodynamic design and three-dimensional flow field check by using the software Concepts NREC and the Numeca. The impeller is made of 0Cr17Ni4Cu4Nb. The strength and vibration characteristics of the centrifugal impeller are analyzed and checked with the ANSYS within the linear elasticity range.[Results] The aerodynamic design results show that the total pressure ratio of the two-stage centrifugal compressor at design mass flow rate is 7.97,the adiabatic efficiency is 80.39% and the stability margin is 17.2%. The results of strength and vibration analysis show that the impeller strength meets material strength requirements. According to the "triple point" resonance theory,there are no risks of resonance vibration for the two-stage centrifugal impellers.[Conclusions] A design scheme for the two-stage centrifugal compressor with high pressure ratio,high efficiency and wide stability margin is obtained,the compressor meeting the requirements for aerodynamics,strength and vibration,which can provide some fundamental support for the design, technology integration and test of a small gas turbine.

Corrosion medium such as CO2-Cl-causing corrosion pits in the pipe wall exist usually in the service environment of well tubing. These pits will become the fatigue source of the fatigue damage of oil tubing under cyclic loading. In this paper,tubing steel of 13 Cr used in oil well is selected as research object,and CO2-Cl- corrosive environment is selected for simulating the service condition of tubing. In the corrosive environment,fatigue experiments are performed on standard CT specimens to study crack propagation behavior of 13 Cr steel. Crack propagation rate of the 13 Cr steel under cyclic loading is measured in air environment,in Cl- environment and in CO2-Cl- corrosive environment respectively. The change of corrosion fatigue crack propagation rate under the three environment condition is carried out. With the observation of fracture morphology, the mechanism of corrosion fatigue failure of the 13 Cr steel in the CO2-Cl- corrosive environment is analyzed.

The geometric parameters are defined according to structural features of RV reducer and the secondary development of ANSYS for parametric modeling is finished by using ANSYS parametric design language（ APDL） and user interface design language（ UIDL） based on tooth profile equation of curtate cycloid and involute. The parametric modeling is proved by using the kinematic simulation through Pro / E. The modal analysis of RV- 40 E is finished and the results is coincided with the experimental modal analysis results. By changing the parameter,a study about influence factors of the first order natural frequency is conducted. The influence curve is obtained and it can become the basis of improving dynamic property. The method of parametric modeling of RV reducer could improve the efficiency of finite element analysis by reducing the workload of modeling and avoiding repeated modeling. The application in modal analysis has laid the foundation for the integration of parametric modeling and finite analysis of RV reducer.

The theoretical formulas of operating frequency are established based on transmission principle and operation mode of RV reducer by using mechanism transformation method and pure rolling hypothesis of bearing roller,and applied to calculating operating frequency of RV- 40 E reducer. The theoretical calculated results are checked by ADAMS simulation,the maximum error of theoretical values is only 4. 19 percent. The autorotation speed of crank throw bearing roller is very high,increasing the roller diameter of crank throw bearing is an effective way to lower roller autorotation speed and improve bearing life. A general,quick and efficient calculating method for rotational frequency of RV reducer transmission parts and rolling bearing parts is provided.

In the context of carbon neutrality, the BRICS countries, representatives of emerging developing countries, have proposed their own adaptation policies and carbon emission reduction targets (CERT). Here, we sort out the evolution of their climate policies and actions over the past half-century. After piecing together their energy structures and carbon emissions from various sources and by different sectors, we see distinct energy structures diverging over time with increasing varieties of non-fossil energy. However, all the BRICS countries, except for Brazil, still rely heavily on fossil fuels, which poses a real challenge to emission reduction. After considering their diversified energy structures, we estimate their timelines for achieving the carbon neutrality goal using the Greenhouse Gas and Air Pollution Interactions and Synergies (GAINS) model. From the model output, we propose possible solutions to help achieve the carbon neutrality goal with respect to their individual status quo and future needs for socioeconomic development. The suggestions include reinforcing the legislation, strengthening cooperation in the fields of energy and carbon management and in core technologies for carbon emission reduction, improving the cooperation mechanisms of the BRICS countries, and further expanding all-round cooperation. [ABSTRACT FROM AUTHOR]

With yeast cell as research objective, the effects of different amounts of gluten antifreeze polypeptides on yeast cell survival rate, cell morphology, cell membrane damage and leakage of cell contents during the freezing or repeated freezing and thawing process were studied. The results showed that a certain mass concentration (20 ~ 40 g/ L) of gluten antifreeze polypeptides could improve the survival rate of yeast cells during the freezing or repeated freezing and thawing process. After repeated freezing and thawing 8 times, the cell survival rate in the yeast suspension supplemented with 40 g/ L gluten antifreeze polypeptide was the highest, which was 65. 63% higher than that in the blank group. Gluten antifreeze polypeptide could slow down the destruction of yeast cells by ice crystals and keep yeast cells relatively intact and smooth surface morphology. The gluten antifreeze polypeptides significantly reduced the proportion of damaged cells during the freezing or repeated freezing and thawing process, and inhibited the leakage of intracellular DNA and GSH to a certain extent. Gluten antifreeze polypeptides improved the survival rate of yeast cells by reducing the adverse effects of ice crystals on cell membranes during the freezing or repeated freezing and thawing process. [ABSTRACT FROM AUTHOR]

The compilation of technology lists of addressing climate change has guiding effect on promoting technological research and development, demonstration and popularization. It is also crucial for China to strengthen ecological civilization construction, achieve the carbon emission peak and carbon neutral target, and enhance global climate governance capabilities. This study first proposes the existing classification outline of the technology promotion lists, technology demand lists and future technology lists. Then, different methodologies are integrated on the basis of the existing outline of four technology lists: China's existing technological promotion list for addressing climate change, China's demand list for climate change mitigation technology, China's key technology list for addressing climate change, and China's future technology list for addressing climate change. What's more, core technologies are analyzed in the aspects of technology maturity, carbon reduction cost, carbon reduction potential, economic benefits, social influence, uncertainty, etc. The results show that: key industries and sectors in China already have relatively mature mitigation/adaptation technologies to support the achievement of climate change targets. The multi-sectoral system of promoting climate-friendly technologies has been established, which has played an active role in tackling climate change. Currently, climate technology needs are concentrated in the traditional technology and equipment upgrading, renewable energy technology and management decision-making support technology. The key technologies are concentrated in 3 major areas and 12 technological directions that urgently need a breakthrough. For carbon emmission peak and carbon nentrality, carbon depth reduction/zero carbon emissions and geoengineering technology ( CDR and SRM) have played an important role in forming the structure of global emissions and achieving carbon neutrality in the future. Thus, the uncertainty assessment for the comprehensive technology cost-effectiveness, technology integration direction, technical maturity, ethics and ecological impacts is supportive to the national technology strategy. Finally, the presented study proposes several policy suggestions for medium-and long-term technology deployment, improving technology conversion rate, promoting the research and development of key core technologies, and forming a technology list collaborative update and release mechanism. [ABSTRACT FROM AUTHOR]

The stress-strain data in uniaxial, planar and biaxial tension tests of standard rubber specimen are measured, based on which the parameters of 5 common hyperelastic constitutive models are identified with least square principle, and the fitting accuracies of different models are compared. Then taking the rubber isolator of a real vehicle as an example, its force-displacement curves under three typical engineering strains with different constitutive models are calculated and compared with measured data. The results show that in dealing with smaller strain values, Mooney-Rivlin model has the highest accuracy and computational stability among all the models, while in dealing with large strain values, Van der Waals model and Ogden3 model have better accuracies than other models. [ABSTRACT FROM AUTHOR]

A case of ectodermal dysplasia syndrome was reported in this article. This case report and relevant lite-rature of ectodermal dysplasia syndrome let us know the clinical symptom, etiology and effect factors of heredity of this disease. [ABSTRACT FROM AUTHOR]

Objective: To explore the safety and effectiveness of one-stage posterior eggshell osteotomy and long-segment pedicle screw fixation in the treatment of ankylosing spondylitis kyphosis combined with acute thoracolumbar vertebral fracture., Methods: A clinical data of 20 patients with ankylosing spondylitis kyphosis combined with acute thoracolumbar spine fracture, who were treated with one-stage posterior eggshell osteotomy and long-segment pedicle screw fixation between April 2016 and January 2022, was retrospectively analyzed. Among them, 16 cases were male and 4 cases were female; their ages ranged from 32 to 68 years, with an average of 45.9 years. The causes of injury included 10 cases of sprain, 8 cases of fall, and 2 cases of falling from height. The time from injury to operation ranged from 1 to 12 days, with an average of 7.1 days. The injured segment was T 11 in 2 cases, T 12 in 2 cases, L 1 in 6 cases, and L 2 in 10 cases. X-ray film and CT showed that the patients had characteristic imaging manifestations of ankylosing spondylitis, and the fracture lines were involved in the anterior, middle, and posterior columns and accompanied by different degrees of kyphosis and vertebral compression; and MRI showed that 12 patients had different degrees of nerve injuries. The operation time, intraoperative bleeding, intra- and post-operative complications were recorded. The visual analogue scale (VAS) score and Oswestry disability index (ODI) were used to evaluate the low back pain and quality of life, and the American spinal cord injury association (ASIA) classification was used to evaluate the neurological function. X-ray films were taken, and local Cobb angle (LCA) and sagittal vertical axis (SVA) were measured to evaluate the correction of the kyphosis., Results: All operations were successfully completed and the operation time ranged from 127 to 254 minutes (mean, 176.3 minutes). The amount of intraoperative bleeding ranged from 400 to 950 mL (mean, 722.5 mL). One case of dural sac tear occurred during operation, and no cerebrospinal fluid leakage occurred after repair, and the rest of the patients did not suffer from neurological and vascular injuries, cerebrospinal fluid leakage, and other related complications during operation. All incisions healed by first intention without infection or fat liquefaction. All patients were followed up 8-16 months (mean, 12.5 months). The VAS score, ODI, LCA, and SVA at 3 days after operation and last follow-up significantly improved when compared with those before operation ( P <0.05), and the difference between 3 days after operation and last follow-up was not significant ( P >0.05). The ASIA grading of neurological function at last follow-up also significantly improved when compared with that before operation ( P <0.05), including 17 cases of grade E and 3 cases of grade D. At last follow-up, all bone grafts achieved bone fusion, and no complications such as loosening, breaking of internal fixation, and pseudoarthrosis occurred., Conclusion: One-stage posterior eggshell osteotomy and long-segment pedicle screw fixation is an effective surgical procedure for ankylosing spondylitis kyphosis combined with acute thoracolumbar vertebral fracture. It can significantly relieve patients' clinical symptoms and to some extent, alleviate the local kyphotic deformity.

Objective: To investigate the effects of blocking the activation of ERK pathway on the expression of matrix metalloproteinase-9 (MMP-9) and the formation of cerebral edema in SD rats after brain injury., Methods: Ninety SD rats were randomly divided into 3 equal groups, including a sham-operated group, modified Feeney's traumatic brain injury model group, and ERK inhibition group where the ERK inhibitor SCH772984 (500 μg/kg) was injected via the femoral vein 15 min before brain trauma. At 2 h and 2 days after brain trauma, the permeability of blood-brain barrier was assessed by Evans blue method, the water content of the brain tissue was determined, and the phosphorylation level of ERK and the expression level of MMP-9 mRNA and protein were measured by RT-PCR and Western blotting., Results: Compared with the sham-operated group, the rats with brain trauma exhibited significantly increased level of ERK phosphorylation at 2 h and significantly increased expression of MMP-9 mRNA and protein 2 days after the injury ( P &lt; 0.01). Treatment with the ERK inhibitor significantly decreased the phosphorylation level of ERK after the injury ( P &lt; 0.01), suppressed over-expression of MMP-9 mRNA and protein 2 days after the injury ( P &lt; 0.01). The permeability of blood-brain barrier increased significantly 2 h after brain trauma ( P &lt; 0.05) and increased further at 2 days ( P &lt; 0.01); the water content of the brain did not change significantly at 2 h ( P &gt; 0.05) but increased significantly 2 d after the injury ( P &lt; 0.01). Treatment with the ERK inhibitor significantly lowered the permeability of blood-brain barrier and brain water content after brain trauma ( P &lt; 0.01)., Conclusions: Blocking the activation of ERK pathway significantly reduced the over-expression of MMP-9 and alleviates the damage of blood-brain barrier and traumatic brain edema, suggesting that ERK signaling pathway plays an important role in traumatic brain edema by regulating the expression of MMP-9.

Objective: To investigate the feasibility of fabricating an oriented scaffold combined with chondrogenic-induced bone marrow mesenchymal stem cells (BMSCs) for enhancement of the biomechanical property of tissue engineered cartilage in vivo., Methods: Temperature gradient-guided thermal-induced phase separation was used to fabricate an oriented cartilage extracellular matrix-derived scaffold composed of microtubules arranged in parallel in vertical section. No-oriented scaffold was fabricated by simple freeze-drying. Mechanical property of oriented and non-oriented scaffold was determined by measurement of compressive modulus. Oriented and non-oriented scaffolds were seeded with chondrogenic-induced BMSCs, which were obtained from the New Zealand white rabbits. Proliferation, morphological characteristics, and the distribution of the cells on the scaffolds were analyzed by MTT assay and scanning electron microscope. Then cell-scaffold composites were implanted subcutaneously in the dorsa of nude mice. At 2 and 4 weeks after implantation, the samples were harvested for evaluating biochemical, histological, and biomechanical properties., Results: The compressive modulus of oriented scaffold was significantly higher than that of non-oriented scaffold (t=201.099, P=0.000). The cell proliferation on the oriented scaffold was significantly higher than that on the non-oriented scaffold from 3 to 9 days (P < 0.05). At 4 weeks, collagen type II immunohistochemical staining, safranin O staining, and toluidine blue staining showed positive results in all samples, but negative for collagen type I. There were numerous parallel giant bundles of densely packed collagen fibers with chondrocyte-like cells on the oriented-structure constructs. Total DNA, glycosaminoglycan (GAG), and collagen contents increased with time, and no significant difference was found between 2 groups (P > 0.05). The compressive modulus of the oriented tissue engineered cartilage was significantly higher than that of the non-oriented tissue engineered cartilage at 2 and 4 weeks after implantation (P < 0.05). Total DNA, GAG, collagen contents, and compressive modulus in the 2 tissue engineered cartilages were significantly lower than those in normal cartilage (P < 0.05)., Conclusion: Oriented extracellular matrix-derived scaffold can enhance the biomechanical property of tissue engineered cartilage and thus it represents a promising approach to cartilage tissue engineering.

A case of ectodermal dysplasia syndrome was reported in this article. This case report and relevant literature of ectodermal dysplasia syndrome let us know the clinical symptom, etiology and effect factors of heredity of this disease.

We isolated the strain MBL13 with high collagenase productivity from the soil of piled up animal bones. It was identified as Bacillus cereus. We purified and characterized Bacillus cereus collagenase (BCC). The molecular weight of BCC was 38.0 kDa and the optimum temperature and pH for the enzyme activity were 40 degrees C and 8.0 respectively. The enzyme was stable when the temperature was below 50 degrees C, but only retained 10% activity when kept at 60 degrees C for 1 h. The enzyme activity was stable between pH 7.0-8.5. Some metal ions such as Ca2+, Zn2+, Mg2+ enhanced the enzyme activity, and Cu2+ brought the obvious inhibition. In addition, EDTA and EGTA could inhibit the enzyme activity. We suggested that the purified enzyme was a member of the metalloproteases. Based on the experiment of substrate specificity, we found that the purified enzyme was bone collagenolytic protease, and had a much stronger capacity of hydrolysis for type I collagen than that for type II collagen and type III collagen. By BCC hydrolyzing bone collagen, we obtained polypeptides with different chain lengths. The comparative test indicated that the hydrolysis capacity of BBC was higher than that of standard type I collagenase. The results introduced a new strain and a novel collagenolytic protease for industrial enzyme.

Unlabelled: We retrospectively reviewed 115 cases of living donors for right lobes of liver transplants, not including the middle hepatic veins, in our hospital. The weights and volumes of the right lobe liver grafts were measured and recorded in the surgery. The actual total volume of liver was calculated from the right lobe graft volume divided by the proportion of the right lobe as indicated in the computed tomography. Simple linear regression analysis and stepwise multiple linear regression analysis were undertaken to develop a formula for calculating the total liver volume, which was compared with other existing formulae., Results: The liver donors had a mean age of (35.97 +/- 9.6) years old, and a female to male ratio of 60:55. The computed tomography detected a mean volume of (727.47 +/- 136.17) mL of right lobe, which occupied 55.59% +/- 6.70% of the entire livers. The right lobe grafts had an actual volume of (581.73 +/- 96.137) mL and the donors had an actual total liver volume of (1053.08 +/- 167.56) mL. A formula was developed for calculating the standard liver volume: SLV(mL) = 11.508 x Body Weight + 334.024. The HongKong formula underestimated, whereas all of the other formulae overestimated the actual liver volume of the donors. Conclusion The standard liver volume of Chinese adults can be calculated as: SLV = 11.508 x Body Weight + 334.024.