Progress in the generation of spinal cord organoids over the past decade and future perspectives

Spinal cord organoids are three-dimensional tissues derived from stem cells that recapitulate the primary morphological and functional characteristics of the spinal cord in vivo.As emerging bioengineering methods have led to the optimization of cell culture protocols,spinal cord organoids technology has made remarkable advancements in the past decade.Our literature search found that current spinal cord organoids do not only dynamically simulate neural tube formation but also exhibit diverse cytoarchitecture along the dorsal-ventral and rostral-caudal axes.Moreover,fused organoids that integrate motor neurons and other regionally specific organoids exhibit intricate neural circuits that allows for functional assessment.These qualities make spinal cord organoids valuable tools for disease modeling,drug screening,and tissue regeneration.By utilizing this emergent technology,researchers have made significant progress in investigating the pathogenesis and potential therapeutic targets of spinal cord diseases.However,at present,spinal cord organoid technology remains in its infancy and has not been widely applied in translational medicine.Establishment of the next generation of spinal cord organoids will depend on good manufacturing practice standards and needs to focus on diverse cell phenotypes and electrophysiological functionality evaluation.

The Impact of Nova Outbursts on the Chemical Abundance of the Interstellar Medium

Nova outbursts are the results of thermonuclear runaways,which occur when sufficient material accretes on the surfaces of white dwarfs(WDs).Using the MESA code,we construct a detailed grid for carbon-oxygen and oxygen-neon-magnesium novae.By employing population synthesis methods,we conduct a statistical analysis of the distribution of novae in the Milky Way.In our models,on average,a typical nova system may undergo about8000 eruptions and the Galactic nova rate is~130 yr^(-1).The C,N,and O elements in nova ejecta are strongly affected by the mixing degree between WD core and accreted material.Our results show that the average value of^(12)C/^(13)C in nova ejecta is about an order of magnitude lower than that on the surface of a red giant,that for^(16)O/^(17)O is about 5 times lower,and that for^(14)N/^(15)N is about 1.5 times lower.The annual yields of^(13)C,^(15)N,and^(17)O from nova ejection are larger than those from AGB stars.This indicates that compared to a red giant,nova eruptions are a more important source of the odd-numbered nuclear elements of^(13)C,^(15)N,and^(17)O in the Galactic interstellar medium.

COSO-ERM(2017)框架下公立医院预算管理优化研究

预算管理是公立医院内部控制中非常重要的一环,提升公立医院预算管理水平符合国家对公立医院改革的要求。基于COSO-ERM框架,提出风险导向下医院预算管理优化措施。研究结论表明通过推广风险管理文化、建立战略导向型预算、建立风险识别评估与应对机制、加强监督与信息沟通可以优化医院预算管理。

Economy, environmental assessment and energy conservation for separation of isopropanol/diisopropyl ether/water multi-azeotropes via extractive distillation coupled pervaporation process

This wok proposed the extraction distillation coupled pervaporation(ED+PV) technology process using two different solvents to separate isopropanol(IPA) and diisopropyl ether(DIPE) from DIPE/IPA/H_(2)O ternary heterogeneous azeotropes in industrial wastewater from the synthesis of isopropanol in this study.Based on strict design specifications, simulation and sequential iteration methods are used for process design and optimization. Compared to the ethylene glycol(EG)-EG+H_(2)O process and the 1,3-propanediol(PDO)-IPA+H_(2)O process, the total annual cost(TAC) of the EG-IPA+H_(2)O process decreased by 20.76% and 7.86%(PDO). Compared to the EG-EG+H_(2)O process, the TAC of the PDO-IPA+H_(2)O process reduced 14%, but the global warming potential(GWP) and human toxicity of the PDO-IPA+H_(2)O process increased 11.3% and 4.07% respectively. Compared to the PDO-IPA+H_(2)O process, the EG-IPA+H_(2)O process saves 7.86%(TAC), 9.78%(GWP) and 9.85%(human toxicity). The ED+PV process with EG is superior to PDO in factors of TAC, energy consumption, human toxicity and environment. The EG-IPA+H_(2)O process changed the separation order of the products of the multi-azeotropic system, reduced the cost and energy conservation of the system, and enhanced the environmental protection evaluation of the process, is the best process through life cycle assessment for analyzing the economy, energy conservation, environmental assessment and human toxicity, designing cleaner products, controlling waste discharge, and promoting the chemical purification industry. This work provides a new process design and optimized separation ideas, will have a good guiding significance for the research and application separation of multi-azeotropic mixture with mixed solvents in organic wastewater from the cleaner chemical production, has been up to standard wastewater discharge process, and realized the development goal of carbon peak and carbon neutrality in the sustainable development of chemical clean industry.

Phloem unloading in cultivated melon fruits follows an apoplasmic pathway during enlargement and ripening

Melon(Cucumis melo L.)has a long history of cultivation worldwide.During cultivation,domestication,and selection breeding,the sugar content of mature melon fruits has been significantly increased.Compared with unsweet melon and wild melon,rapid sucrose accumulation can occur in the middle and late stages of sweet melon fruit development.The phloem unloading pathway during the evolution and development of melon fruit has not been identified and analyzed.In this study,the phloem unloading pathway and the function of related sugar transporters in cultivated and wild melon fruits were analyzed by CFDA[5(6)-carbofluorescein diacetate]and esculin tracing,cytological pathway observation,qRT–PCR,and gene function analysis,etc.Results show that the phloem unloading pathway of wild melon fruit is largely symplastic,whereas the phloem unloading pathway of cultivated melon fruit shifts from symplastic to apoplasmic during development.According to a fruit grafting experiment,the fruit sink accumulates sugars independently.Correlation analysis showed that the expression amounts of several sucrose transporter genes were positively correlated with the sucrose content of melon fruit.Furthermore,CmSWEET10 was proved to be a sucrose transporter located on the plasma membrane of the phloem and highly expressed in the premature stage of sweet melon fruits,which means it may be involved in phloem apoplast unloading and sucrose accumulation in sweet melon fruits.Finally,we summarize a functional model of related enzymes and sugar transporters involved in the apoplast unloading of sweet melon fruits during enlargement and sucrose accumulation.

Energy,exergy,economic and environmental comprehensive analysis and multi-objective optimization of a sustainable zero liquid discharge integrated process for fixed-bed coal gasification wastewater

For a long time,China's regional water resource imbalance has restricted the development of coal chemical industry,and it is imperative to achieve zero liquid discharge(ZLD).Therefore,the game relationship between technical indicators,costs and emissions in ZLD process of fixed-bed coal gasification wastewater treatment process should be explored in detail.According to the accurate model,the simulation for ZLD of fixed-bed coal gasification wastewater treatment process is established,and this process is assessed from the perspective of thermodynamics,economy,and environment.The total energy consumption of ZLD process before optimization is 4.032×10^(8)W.The results of exergy analysis show exergy destruction of ZLD process is 94.55%.For economic and environmental results,the total annual cost is 1.892×10^(7)USD·a^(-1)and the total environmental impact is 4.782×10^(-8).The total energy consumption of the optimal six-step ZLD process based on multi-objective optimization is 4.028×10^(8)W.The CO_(2)content in the treated wastewater is 0.1%.This study will have an important role in promoting the establishment of the ZLD process for coal chemistry industry.

Comprehensive analysis on the economy and energy demand of pressure-swing distillation and pervaporation for separating waste liquid containing multiple components

A large amount of waste liquids containing methanol/acetone/water mixtures are produced in the synthesis of methyl methacrylate(MMA).Under the advocacy of green chemical industry,it is urgent to develop an efficient,economic and energy-saving mixture separation process.Through thermodynamic azeotropic behavior and pressure sensitivity analysis,pressure-swing distillation was determined and the optimal separation pressure of each column in the process was obtained.Due to the composition of waste liquids produced were quite different in MMA production,the pressure-swing distillation separation process was designed to fully achieve the accurate waste liquids treatment.Taking the total annual cost(TAC)as the target,the sequential iteration method was used to optimize the process,and the impact of composition on economy was compared.In order to further realize the energy-saving of the separation process,the pervaporation membrane module was introduced to pretreat the waste liquid in the pressure-swing distillation.The results showed that the TAC of the coupling process was 46% higher than that of the pressure-swing distillation process,and the thermodynamic efficiency was 30% higher.This study provides waste liquid treatment technology for enterprises and analyzes its economic and energy efficiency,which has reference significance for the development of coupled separation technology.

Study of beam divergence and thrust vector eccentricity characteristics of the Hall thruster based on dual Faraday probe array planes and its applications

The accurate knowledge of the thrust vector eccentricity and beam divergence characteristics of Hall thrusters are of significant engineering value for the beneficial integration and successful application of Hall thrusters on spacecraft.For the characteristics of the plume bipolar diffusion due to the annular discharge channel of the Hall thruster,a Gaussian-fitted method for thrust vector deviation angle and beam divergence of Hall thrusters based on dual Faraday probe array planes was proposed in respect of the Hall thruster beam characteristics.The results show that the ratios of the deviation between the maximum and minimum values of the beam divergence angle and the thrust vector eccentricity angle using a Gaussian fit to the optimized Faraday probe dual plane to the mean value are 1.4%and 11.5%,respectively.The optimized thrust vector eccentricity angle obtained has been substantially improved,by approximately 20%.The beam divergence angle calculated using a Gaussian fitting to the optimized Faraday probe dual plane is approximately identical to the non-optimized one.The beam divergence and thrust vector eccentricity angles for different anode mass flow rates were obtained by averaging the beam divergence and thrust vector eccentricity angles calculated by the dual-plane,Gaussian-fitted ion current density method for different cross-sections.The study not only allows for an immediate and effective tool for determining the design of thrust vector adjustment mechanisms of spacecraft with different power Hall thrusters but also for characterizing the 3D spatial distribution of the Hall thruster plume.

Experimental and numerical simulation study of the effect for the anode positions on the discharge characteristics of 300W class low power Hall thrusters

Low-power Hall thruster(LHT) generally has poor discharge efficiency characteristics due to the large surface-to-volume ratio.Aiming to further refine and improve the performance of 300 W class LHT in terms of thrust and efficiency,and to obtain the most optimal operating point,the experimental study of the discharge characteristics for three different anode positions was conducted under the operation of various discharge voltages(100-400 V) and anode mass flow rates(0.65 mg·s-1and 0.95 mg·s-1).The experimental results indicated that the thruster has the most excellent performance in terms of thrust and efficiency etc at a channel length of 27 mm for identical operating conditions.In addition,particle in cell simulations,employed to reveal the underlying physical mechanisms,show that the ionization and acceleration zone is pushed downwards towards the channel exit as the anode moves towards the exit.At the identical operating point,when the channel length is reduced from 32 to 27 mm,the ionization and acceleration zone moves towards the exit,and the parameters such as thrust and efficiency increase due to the high ionization rate,ion number density,and axial electric field.When the channel length is further moved to 24 mm,the parameters in terms of thrust(F) and efficiency(ηa) are reduced as a result of the decreasing ionization efficiency(ηm) and the larger plume divergence angle(α).In this paper,the results indicated that an optimum anode position(ΔL=27 mm) exists for the optimum performance.

氯化镁/甘油改性淀粉/聚丁二酸丁二醇酯共混材料的结构与性能

为了改善淀粉/聚丁二酸丁二醇酯(PBS)共混材料的相容性和力学性能,文中以氯化镁/甘油为复配改性剂,采用熔融共混方法制备了改性淀粉/聚丁二酸丁二醇酯共混材料,研究了改性共混材料的红外吸收特性、形态结构、热性能、力学性能及结晶性能。研究结果表明,氯化镁和甘油可与淀粉/PBS共混材料产生强相互作用,破坏淀粉/PBS共混材料原有的氢键与结晶结构,提高淀粉与PBS的相容性,使共混材料的玻璃化转变温度、结晶温度、冷结晶温度及结晶度降低;采用氯化镁/甘油复配改性剂可制备出具有良好性能的淀粉/PBS共混材料,改性后的淀粉/PBS共混材料的断裂伸长率和拉伸强度均得到提高。

Analysis on the Demand and Countermeasures of Air Ground Coordination in China’s Aviation Medical Rescue

Compared with ground first aid, aviation medical rescue has better advantages in mountain disaster relief, remote transfer and rapid medical rescue response, which is an effective supplement to ground medical first aid. China’s aviation medical rescue is in its infancy, compared with the level of developed countries there is a big gap. Based on the development and characteristics of aviation medical rescue in China, this paper combs the process of air-ground cooperative rescue, analyzes the demand and current situation of air-ground cooperative rescue in aviation medical rescue in China, and puts forward some countermeasures to improve the ability of aviation medical rescue in China.

重视标准D2胃癌根治术中No.8淋巴结清扫

临床研究证实进展期胃癌No.8淋巴结的转移发生率较高.能否彻底清扫No.8淋巴结将会影响胃癌的R0切除率和术后复发率.No.8淋巴结清扫的范围与程度仍存在争议.本文就标准D2胃癌根治术中No.8淋巴结清扫的相关问题作一综述.

园林企业消耗性生物资产审计风险控制对策案例研究

财务造假案例中不乏存货造假的身影,存货成为众多上市公司财务造假的后花园和重灾区。园林企业的存货中消耗性生物资产占据比例较高,因其复杂性和特殊性,审计师对这种类型企业的消耗性生物资产进行审计需耗费较多的心血,同时也将承担更高的审计风险。如何降低园林企业消耗性生物资产的审计风险,提高审计业务水平,为财务报表预期使用者提供一份公允反映企业财务状况的报告,这是所有审计人员的共同心愿。本文通过分析园林企业消耗性生物资产的审计流程,深刻揭露消耗性生物资产蕴含的审计风险,进而提出有效的方法和手段对园林企业消耗性生物资产审计风险进行有效控制,这对会计师事务所的内部管理工作具有现实指导意义。

BSC模型下海尔智家数字化转型的战略绩效评价体系研究

数字化正在成为推动我国经济持续平稳发展的重要驱动力,建立科学规范的数字化转型战略绩效评价体系能够为我国企业数字化转型指明方向。以财务数据为主的传统绩效评价已无法全面真实的反映企业的转型绩效数字化。针对该局限性,本文以海尔智家的战略为导向,绘制了海尔智家数字化转型战略地图,并借助平衡计分卡构建战略绩效评价数字化转型战略评价体系。结果表明海尔智家数字化转型效果显著。评价体系的构建为企业指明转型方向,对企业成功进行数字化转型具有重要意义。

发展情报学思想的产生及其理论研究进展

[目的/意义]学习借鉴国外发展情报学的创新发展成功经验,推动具有中国特色的情报学研究健康发展及理论体系建设。[方法/过程]运用历史追溯和对比分析的方法,对近50年来发展情报学理论与应用的历史概况和主要领域研究进展进行了全面归纳总结。[结果/结论]认为与西方经典情报学相比,发展情报学的研究成果已在学科重点问题设定、理论体系基本假设修正和理论与实践紧密结合三个方面取得创新突破,在很大程度上拓展了情报科学的研究范畴及其应用价值。

Craniocerebral injury promotes the repair of peripheral nerve injury

The increase in neurotrophic factors after craniocerebral injury has been shown to promote fracture healing. Moreover, neurotrophic factors play a key role in the regeneration and repair of peripheral nerve. However, whether craniocerebral injury alters the repair of peripheral nerve injuries remains poorly understood. Rat injury models were established by transecting the left sciatic nerve and using a free-fall device to induce craniocerebral injury. Compared with sciat- ic nerve injury alone after 6-12 weeks, rats with combined sciatic and craniocerebral injuries showed decreased sciatic functional index, increased recovery of gastrocnemius muscle wet weight, recovery of sciatic nerve ganglia and corresponding spinal cord segment neuron mor- phologies, and increased numbers of horseradish peroxidase-labeled cells. These results indicate that craniocerebral injury promotes the repair of peripheral nerve injury.

Radiofrequency ablation for single hepatocellular carcinoma 3 cm or less as first-line treatment

AIM:To evaluate long-term outcomes of radiofrequency(RF) ablation as first-line therapy for single hepatocellular carcinoma(HCC) ≤ 3 cm and to determine survival and prognostic factors.METHODS:We included all 184 patients who underwent RF ablation as a first-line treatment for single HCC ≤ 3 cm between April 2005 and December 2013.According to the criteria of Livraghi,the 184 patients were divided into two groups:those suitable for surgical resection(84 cases) and those unsuitable for surgical resection(100 cases).The primary endpoints were the overall survival(OS) rate and safety;the secondary endpoints were primary technique effectiveness and recurrence rate.RESULTS:There were 19(10.3%) cases of ablation related minor complications.The complete tumor ablation rate after one RF session was 97.8%(180/184).The rate of local tumor progression,extrahepatic metastases and intrahepatic distant recurrence were 4.9%(9/184),9.8%(18/184) and 37.5%(69/184),respectively.In the 184 patients,the 1-,3-,and 5-year OS rates were 99.5%,81.0%,and 62.5%,respectively.The 1-,3-,and 5-year OS rates were 100%,86.9%,and 71.4%,respectively,in those suitable for surgical resection and 99.0%,76.0%,and 55.0%,respectively,in those unsuitable for surgical resection(P = 0.021).On univariate and multivariate analyses,poorer OS was associated with Child-Pugh B class and portal hypertension(P < 0.05).CONCLUSION:RF ablation is a safe and effective treatment for single HCC ≤ 3 cm.The OS rate of patients suitable for surgical resection was similar to those reported in surgical series.

Laparoscopic vs computerized tomography-guided radiofrequency ablation for large hepatic hemangiomas abutting the diaphragm

AIM: To compare safety and therapeutic efficacy of laparoscopic radiofrequency(RF) ablation vs computed tomography(CT)-guided RF ablation for large hepatic hemangiomas abutting the diaphragm.METHODS: We retrospectively reviewed our sequential experience of treating 51 large hepatic hemangiomas abutting the diaphragm in 51 patients by CT-guided or laparoscopic RF ablation due to either the presence of symptoms and/or the enlargement of hemangioma.Altogether, 24 hemangiomas were ablated via a CTguided percutaneous approach(CT-guided ablation group), and 27 hemangiomas were treated via a laparoscopic approach(laparoscopic ablation group).RESULTS: The mean diameter of the 51 hemangiomas was 9.6 ± 1.8 cm(range, 6.0-12.0 cm). There was nodifference in the diameter of hemangiomas between the two groups(P > 0.05). RF ablation was performed successfully in all patients. There was no difference in ablation times between groups(P > 0.05). There were 23 thoracic complications in 17 patients: 15(62.5%, 15/24) in the CT-guided ablation group and2(7.4%, 2/27) in the laparoscopic ablation group(P< 0.05). According to the Dindo-Clavien classification,two complications(pleural effusion and diaphragmatic rupture grade Ⅲ) were major in two patients. All others were minor(grade Ⅰ). Both major complications occurred in the CT-guided ablation group. The minor complications were treated successfully with conservative measures, and the two major complications underwent treatment by chest tube drainage and thoracoscopic surgery, respectively. Complete ablation was achieved in 91.7%(22/24) and 96.3%(26/27) in the CT-guided and the laparoscopic ablation groups,respectively(P > 0.05).CONCLUSION: Laparoscopic RF ablation therapy should be used as the first-line treatment option for large hepatic hemangiomas abutting the diaphragm.It avoids thermal injury to the diaphragm and reduces thoracic complications.

A review of extractive distillation from an azeotropic phenomenon for dynamic control

Extractive distillation is an effective method for separating azeotropic or close boiling point mixtures by adding a third component.Various technologies for performing the extractive distillation process have been explored to protect the environment and save resources.This paper focuses on the improvement of these advanced technologies in recent years.Extractive distillation is retrieved and analyzed from the view of phase equilibrium,selection of solvent in extractive distillation,process design,energy conservation,and dynamic control.The quantitative structure–property relationship used in extractive distillation is discussed,and the future development of extractive distillation is proposed to determine how the solvent affects the relative volatility of the separated mixture.In the steady state design,the relationship between the curvature of the residue curve and parameters of the optimal steady state is also highlighted as another field worthy of further study to simplify the distillation process.

Practical constrained least-square algorithm for moving source location using TDOA and FDOA measurements

By utilizing the time difference of arrival （TDOA） and frequency difference of arrival （FDOA） measurements of signals received at a number of receivers, a constrained least-square （CLS） algorithm for estimating the position and velocity of a moving source is proposed. By utilizing the Lagrange multipliers technique, the known relation between the intermediate variables and the source location coordinates could be exploited to constrain the solution. And without requiring apriori knowledge of TDOA and FDOA measurement noises, the proposed algorithm can satisfy the demand of practical applications. Additionally, on basis of con- volute and polynomial rooting operations, the Lagrange multipliers can be obtained efficiently and robustly allowing real-time imple- mentation and global convergence. Simulation results show that the proposed estimator achieves remarkably better performance than the two-step weighted least square （WLS） approach especially for higher measurement noise level.