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Novel drive mechanism for in-tube micro robots

CHEN Yangzhi, XING Guangquan, PENG Xuefei, LIU Wenguang, YAO Huaping

《机械工程前沿（英文）》 2007年 第2卷 第1期   页码 94-98 doi: 10.1007/s11465-007-0016-8

摘要： The volume of an in-tube micro robot is small and its interior space is very limited. However, conventional transmission methods are unfit to drive in-tube micro robots. A novel micro drive mechanism called the micro-elastic-meshing-wheel is presented in this paper. It can be used for transmitting power and locomotion between two shafts, which are upright and cross in a micro space. The mechanical model of the novel drive mechanism is built, and the maximal transmission force is deduced. Then, sufficient experiments are carried out to test maximal transmission force produced by the novel drive mechanism. The calculation and experiment results show that the novel drive mechanism can transmit sufficient power to in-tube micro robots.

关键词： limited     conventional transmission     maximal transmission     upright     calculation    

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Telomeric impact of conventional chemotherapy

null

《医学前沿（英文）》 2013年 第7卷 第4期   页码 411-417 doi: 10.1007/s11684-013-0293-z

摘要：

The increased level of chromosome instability in cancer cells, leading to aneuploidy and gross chromosomal rearrangements, is not only a driving force for oncogenesis but also can be the Achille’s heel of the disease since many chemotherapies (CT) kill cells by inducing a non-tolerable rate of DNA damage. A wealth of published evidence showed that telomere stability can be more affected than the bulk of the genome by several conventional antineoplasic drugs. These results raise the interesting possibility that CT with genotoxic drugs preferentially target telomeres. In agreement with this view, accelerated shortening of telomere length has been described in blood lineage cells following high-dose CT (stem cell transplantation) or non-myeloablative CT. However, almost nothing is known on the consequences of this shortening in terms of telomere stability, senescence and on the development of second cancers or post-treatment aging-like syndromes in cancer survivors (cognitive defect, fertility impairment, etc.). In this article, we propose: (1) telomeres of cancer cells are preferential genomic targets of chemotherapies altering chromosome maintenance; (2) telomere functional parameters can be a surrogate marker of chemotherapy sensitivity and toxicity; (3) the use of anti-telomere molecule could greatly enhance the sensitivity to standards chemotherapies.

关键词： telomere     antineoplasic drugs     conventional chemotherapies    

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Choosing configurations of transmission line tower grounding by back flashover probability value

Dmitry KUKLIN

《能源前沿（英文）》 2016年 第10卷 第2期   页码 213-226 doi: 10.1007/s11708-016-0398-6

摘要： There is a considerable number of works devoted to electrical characteristics of grounding. These characteristics are important in general. However, in application to grounding of transmission line towers they are not enough to determine what grounding construction is preferable in some particular case, because these characteristics are calculated or measured apart from the grounded object, and only limited number of current (or voltage) source waveforms is used. This paper indicates reasons in favor of the fact that to choose the optimum design of grounding, the calculation model should include the tower as it is. The probability of back flashover, which provides both qualitative and quantitative estimate of the grounding structure efficiency, can be taken as the criterion for the grounding design. The insulation flashover probability is calculated on the basis of engineering method, which evaluates breakdown strength of insulation for nonstandard waveshapes, and probability data on lightning currents. Different approaches are examined for identifying the back flashover probability, as not only amplitudes but also other parameters can be taken into account. Finite-difference time-domain method is used for calculations of transients. It is found that lightning current waveform can greatly influence calculated back flashover probability value.

关键词： grounding     transmission line tower     back flashover probability     FDTD method    

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Oxygen reduction electrocatalysis: From conventional to single-atomic platinum-based catalysts for proton

《能源前沿（英文）》 doi: 10.1007/s11708-023-0907-3

摘要： Platinum (Pt)-based materials are still the most efficient and practical catalysts to drive the sluggish kinetics of cathodic oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs). However, their catalysis and stability performance still need to be further improved in terms of corrosion of both carbon support and Pt catalyst particles as well as Pt loading reduction. Based on the developed synthetic strategies of alloying/nanostructuring Pt particles and modifying/innovating supports in developing conventional Pt-based catalysts, Pt single-atom catalysts (Pt SACs) as the recently burgeoning hot materials with a potential to achieve the maximum utilization of Pt are comprehensively reviewed in this paper. The design thoughts and synthesis of various isolated, alloyed, and nanoparticle-contained Pt SACs are summarized. The single-atomic Pt coordinating with non-metals and alloying with metals as well as the metal-support interactions of Pt single-atoms with carbon/non-carbon supports are emphasized in terms of the ORR activity and stability of the catalysts. To advance further research and development of Pt SACs for viable implementation in PEMFCs, various technical challenges and several potential research directions are outlined.

关键词： oxygen reduction electrocatalysis     Pt single-atom catalysts     conventional Pt-based catalysts     design thoughts and synthesis     metal-support interactions    

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Esophageal pulse oximetry is more accurate and detects hypoxemia earlier than conventional pulse oximetry

null

《医学前沿（英文）》 2012年 第6卷 第4期   页码 406-410 doi: 10.1007/s11684-012-0217-3

摘要：

The esophagus is perfused directly by prominent arteries and may provide a more consistent tissue source for pulse oximetry. The goal of this study was to evaluate the sensitivity and accuracy of an esophageal pulse oximetry probe on patients during controlled hypoxemia in comparison to measurements obtained with conventional pulse oximetry (SpulseO2). Forty-five ASA I–II adult patients were included in this prospective observational study. Nellcor digital oximetric probes were placed on finger tips for SpulseO2 before anesthesia. After tracheal intubation, an esophageal probe was placed in the lower segment of the esophagus for esophageal oximetric monitoring (SoesO2). All patients were disconnected from the breathing circuit to establish a controlled hypoxemia, and were re-connected to the breathing circuit and ventilated with 100% oxygen immediately when SoesO2 dropped to 90%. Matched SoesO2 and SpulseO2 readings were recorded when SoesO2measurements were at 100%, 95%, 90% and the lowest reading. The time for SoesO2 and SpulseO2 to drop from 100% to 95%, 90% and return to 100% was recorded. Oxygen saturation from arterial blood samples (SartO2) was also measured at each time point respectively. The linear correlation coefficient of the regression analysis between SartO2 and SoesO2 was 0.954. The mean±2SD of the difference was 0.3%±4.3% for SoesO2vs. SartO2 and 6.8%±5.6% for SpulseO2vs. SartO2 (P<0.001). The 95% confidence interval for the absolute difference between SoesO2 and SartO2 was 0.3% to 0.7% and 6.2% to 7.4% between SpulseO2 and SartO2. The time to reach 90% saturation measured with SoesO2 was approximately 94 seconds earlier than the SpulseO2 (P<0.001). In conclusion, SoesO2 is more accurate and enables earlier detection of hypoxemia when compared to conventional pulse oximetry during hypoxemia for patients undergoing general anesthesia.

关键词： esophageal pulse oximetry     conventional pulse oximetry     hypoxemia    

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Techno-economic characteristics of wastewater treatment plants retrofitted from the conventional activated

《环境科学与工程前沿（英文）》 doi: 10.1007/s11783-021-1483-6

摘要：

While a growing number of wastewater treatment plants (WWTPs) are being retrofitted from the conventional activated sludge (CAS) process to the membrane bioreactor (MBR) process, the debate on the techno-economy of MBR vs. CAS has continued and calls for a thorough assessment based on techno-economic valuation.

关键词： Membrane bioreactor (MBR)     Conventional activated sludge (CAS)     Cost-benefit analysis     Data envelopment analysis     Net profit    

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Nonlinear experimental response of non-conventional composite steel and concrete connection

Tobia ZORDAN, Bruno BRISEGHELLA

《结构与土木工程前沿（英文）》 2009年 第3卷 第1期   页码 42-49 doi: 10.1007/s11709-008-0058-y

摘要： An experiment was carried out on a set of full-scale specimens of a non-conventional connection between a concrete column and a composite steel and concrete beam defined on the basis of a number of requirements. The proposed connection, conceived in the ambit of semi-rigid joints, is aimed at combining general ease of construction with a highly simplified assembly procedure with a satisfying transmission of hogging moment at supports in continuous beams. For this purpose, the traditional shear studs used at the interface between the steel beam and the upper concrete slab, are also employed at the ends of the steel profiles welded horizontally to the end plates. The test is aimed at investigating the hogging moment response of the connection under incremental loads until failure.

关键词： composite connections     nonlinear behaviour     hogging moment     monotonic tests    

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Innovative hybrid reinforcement constituting conventional longitudinal steel and FRP stirrups for improved

Mostafa FAKHARIFAR,Ahmad DALVAND,Mohammad K. SHARBATDAR,Genda CHEN,Lesley SNEED

《结构与土木工程前沿（英文）》 2016年 第10卷 第1期   页码 44-62 doi: 10.1007/s11709-015-0295-9

摘要： The use of fiber reinforced polymer (FRP) reinforcement is becoming increasingly attractive in construction of new structures. However, the inherent linear elastic behavior of FRP materials up to rupture is considered as a major drawback under seismic attacks when significant material inelasticity is required to dissipate the input energy through hysteretic cycles. Besides, cost considerations, including FRP material and construction of pre-fabricated FRP configurations, especially for stirrups, and probable damage to epoxy coated fibers when transported to the field are noticeable issues. The current research has proposed a novel economical hybrid reinforcement scheme for the next generation of infrastructures implementing on-site fabricated FRP stirrups comprised of FRP sheets. The hybrid reinforcement consists of conventional longitudinal steel reinforcement and FRP stirrups. The key feature of the proposed hybrid reinforcement is the enhanced strength and ductility owing to the considerable confining pressure provided by the FRP stirrups to the longitudinal steel reinforcement and core concrete. Reinforced concrete beam specimens and beam-column joint specimens were tested implementing the proposed hybrid reinforcement. The proposed hybrid reinforcement, when compared with conventional steel stirrups, is found to have higher strength, stiffness, and energy dissipation. Design methods, structural behavior, and applicability of the proposed hybrid reinforcement are discussed in detail in this paper.

关键词： FRP     ductility     confinement     seismic     shear    

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AGRI-ENVIRONMENTAL ASSESSMENT OF CONVENTIONAL AND ALTERNATIVE BIOENERGY CROPPING SYSTEMS PROMOTING BIOMASS

《农业科学与工程前沿（英文）》 2022年 第9卷 第2期   页码 284-294 doi: 10.15302/J-FASE-2021435

摘要：

Bioenergy, currently the largest renewable energy source in the EU (64% of the total renewable energy consumption), has sparked great interest to meet the 32% renewable resources for the 2030 bioeconomy goal. The design of innovative cropping systems informed by bioeconomy imperatives requires the evaluate of the effects of introducing crops for bioenergy into conventional crop rotations. This study aimed to assess the impacts of changes in conventional cropping systems in mixed dairy cattle farms redesigned to introduce bioenergy crops either by increasing the biomass production through an increase of cover crops, while keeping main feed/food crops, or by substituting food crops with an increase of the crop rotation length. The assessment is based on the comparison between conventional and innovative systems oriented to feed and biogas production, with and without tillage, to evaluate their agri-environmental performances (biomass production, nitrogen fertilization autonomy, greenhouse gas emissions and biogas production). The result showed higher values in the biogas cropping system than in the conventional and feed ones for all indicators, biomass productivity (27% and 20% higher, respectively), nitrogen fertilization autonomy (26% and 73% higher, respectively), methanogenic potential (77% and 41% higher, respectively) and greenhouse gas emissions (15% and 3% higher, respectively). There were no negative impacts of no-till compared to the tillage practice, for all tested variables. The biogas cropping system showed a better potential in terms of agri-environmental performance, although its greenhouse gas emissions were higher. Consequently, it would be appropriate to undertake a multicriteria assessment integrating agri-environmental, economic and social performances.

关键词： alternative cropping systems / bioeconomy / biogas / biomass production / fertilization autonomy / greenhouse gas assessment    

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Recent transmission of Mycobacterium tuberculosis in China: the implication of molecular epidemiology

null

《医学前沿（英文）》 2018年 第12卷 第1期   页码 76-83 doi: 10.1007/s11684-017-0609-5

摘要：

Tuberculosis (TB) has remained an ongoing concern in China. The national scale-up of the Directly Observed Treatment, Short Course (DOTS) program has accelerated the fight against TB in China. Nevertheless, many challenges still remain, including the spread of drug-resistant strains, high disease burden in rural areas, and enormous rural-to-urban migrations. Whether incident active TB represents recent transmission or endogenous reactivation has helped to prioritize the strategies for TB control. Evidence from molecular epidemiology studies has delineated the recent transmission of ( ) strains in many settings. However, the transmission patterns of TB in most areas of China are still not clear. Studies carried out to date could not capture the real burden of recent transmission of the disease in China because of the retrospective study design, incomplete sampling, and use of low-resolution genotyping methods. We reviewed the implementations of molecular epidemiology of TB in China, the estimated disease burden due to recent transmission of strains, the primary transmission of drug-resistant TB, and the evaluation of a feasible genotyping method of strains in circulation.

关键词： tuberculosis     recent transmission     molecular epidemiology     China    

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Robotic distal pancreatectomy versus conventional laparoscopic distal pancreatectomy: a comparative study

null

《医学前沿（英文）》 2015年 第9卷 第3期   页码 356-360 doi: 10.1007/s11684-015-0404-0

摘要：

Robotic system has been increasingly used in pancreatectomy. However, the effectiveness of this method remains uncertain. This study compared the surgical outcomes between robot-assisted laparoscopic distal pancreatectomy and conventional laparoscopic distal pancreatectomy. During a 15-year period, 35 patients underwent minimally invasive approach of distal pancreatectomy in our center. Seventeen of these patients had robot-assisted laparoscopic approach, and the remaining 18 had conventional laparoscopic approach. Their operative parameters and perioperative outcomes were analyzed retrospectively in a prospective database. The mean operating time in the robotic group (221.4 min) was significantly longer than that in the laparoscopic group (173.6 min) (P = 0.026). Both robotic and conventional laparoscopic groups presented no significant difference in spleen-preservation rate (52.9% vs. 38.9%) (P = 0.505), operative blood loss (100.3 ml vs. 268.3 ml) (P = 0.29), overall morbidity rate (47.1% vs. 38.9%) (P = 0.73), and post-operative hospital stay (11.4 days vs. 14.2 days) (P = 0.46). Both groups also showed no perioperative mortality. Similar outcomes were observed in robotic distal pancreatectomy and conventional laparoscopic approach. However, robotic approach tended to have the advantages of less blood loss and shorter hospital stay. Further studies are necessary to determine the clinical position of robotic distal pancreatectomy.

关键词： distal pancreatectomy     pancreatic neoplasm     robotic surgery    

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Antibiotic resistome mostly relates to bacterial taxonomy along a suburban transmission chain

《环境科学与工程前沿（英文）》 2022年 第16卷 第3期 doi: 10.1007/s11783-021-1466-7

摘要：

• The α-diversities of resistome were lower in manure and compost than in soils.

关键词： Antibiotic resistance genes     Resistome     Bacterial taxonomy     Transmission chain    

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Planet position errors in planetary transmission: Effect on load sharing and transmission error

Miguel IGLESIAS, Alfonso FERNáNDEZ, Ana DE-JUAN, Ramón SANCIBRIáN, Pablo GARCíA

《机械工程前沿（英文）》 2013年 第8卷 第1期   页码 80-87 doi: 10.1007/s11465-013-0362-7

摘要：

In this paper an advanced model of spur gear transmissions developed by the authors is used to study the influence of carrier planet pin hole position errors on the behaviour of the transmission. The model, initially conceived for external gear modeling, has been extended with internal meshing features, and thus increasing its capabilities to include planetary transmission modeling. The new features are presented, along with the summary of the model general approach. The parameters and characteristics of the planetary transmission used in the paper are introduced. The influence of carrier planet pin hole position errors on the planet load sharing is studied, and several static cases are given as examples in order to show the ability of the model. Tangential and radial planet pin hole position errors are considered independently, and the effect of the load level is also taken into account. It is also given attention to the effect on the transmission error of the transmission. Two different configurations for the planetary transmission are used, attending to the fixed or floating condition of the sun, and the differences in terms of load sharing ratio are shown.

关键词： gear     planetary     epicyclic     transmission     load sharing     transmission error    

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Eliminating mother-to-child transmission of HBV: progress and challenges in China

Wenzhan Jing, Jue Liu, Min Liu

《医学前沿（英文）》 2020年 第14卷 第1期   页码 21-29 doi: 10.1007/s11684-020-0744-2

摘要： China has the world’s largest burden of hepatitis B virus (HBV) infection, but the country has made considerable progress in preventing its mother-to-child transmission (MTCT) in the past three decades. This feat is made possible due to the high coverage of birth-dose hepatitis B vaccine (HepB,>95%), hepatitis B surface antigen (HBsAg) screening for pregnant women (>99%), and hepatitis B immunoglobulin plus HepB for newborns whose mothers are HBsAg positive (>99%). Studies on the optimal antiviral treatment regimen for pregnant women with high HBV-DNA load have also been conducted. However, China still faces challenges in eliminating MTCT of HBV. The overall HBsAg prevalence among pregnant women is considered an intermediate endemic. The prevalence of HBsAg among pregnant women from remote, rural, or ethnic minority areas is higher than that of the national level because of limited health resources and public health education for HBV. The coverage for maternal and child healthcare and immunization services should be improved, especially in western regions. Integration of current services to prevent MTCT of HBV with other relevant health services can increase the acceptability, efficiency, and coverage of these services, particularly in remote areas and ethnic minority areas. By doing so, progress toward key milestones and targets to eliminate hepatitis B as the main public health threat by 2030 can be achieved.

关键词： hepatitis B virus     mother-to-child transmission     progress     challenge    

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An approach for evaluating the impact of an intermittent renewable energy source on transmission expansion

Rongrit CHATTHAWORN,Surachai CHAITUSANEY

《信息与电子工程前沿（英文）》 2015年 第16卷 第10期   页码 871-882 doi: 10.1631/FITEE.1500049

摘要： We propose a new robust optimization approach to evaluate the impact of an intermittent renewable energy source on transmission expansion planning (TEP). The objective function of TEP is composed of the investment cost of the transmission line and the operating cost of conventional generators. A method to select suitable scenarios representing the intermittent renewable energy generation and loads is proposed to obtain robust expansion planning for all possible scenarios. A meta-heuristic algorithm called adaptive tabu search (ATS) is employed in the proposed TEP. ATS iterates between the main problem, which minimizes the investment and operating costs, and the subproblem, which minimizes the cost of power generation from conventional generators and curtailments of renewable energy generation and loads. The subproblem is solved by nonlinear programming (NLP) based on an interior point method. Moreover, the impact of an intermittent renewable energy source on TEP was evaluated by comparing expansion planning with and without consideration of a renewable energy source. The IEEE Reliability Test System 79 (RTS 79) was used for testing the proposed method and evaluating the impact of an intermittent renewable energy source on TEP. The results show that the proposed robust optimization approach provides a more robust solution than other methods and that the impact of an intermittent renewable energy source on TEP should be considered.

关键词： Adaptive tabu search     Renewable energy generation     Robust optimization     Transmission expansion planning    

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标题 作者 时间 类型 操作

Novel drive mechanism for in-tube micro robots

CHEN Yangzhi, XING Guangquan, PENG Xuefei, LIU Wenguang, YAO Huaping

期刊论文

Telomeric impact of conventional chemotherapy

null

期刊论文

Choosing configurations of transmission line tower grounding by back flashover probability value

Dmitry KUKLIN

期刊论文

Oxygen reduction electrocatalysis: From conventional to single-atomic platinum-based catalysts for proton

期刊论文

Esophageal pulse oximetry is more accurate and detects hypoxemia earlier than conventional pulse oximetry

null

期刊论文

Techno-economic characteristics of wastewater treatment plants retrofitted from the conventional activated

期刊论文

Nonlinear experimental response of non-conventional composite steel and concrete connection

Tobia ZORDAN, Bruno BRISEGHELLA

期刊论文

Innovative hybrid reinforcement constituting conventional longitudinal steel and FRP stirrups for improved

Mostafa FAKHARIFAR,Ahmad DALVAND,Mohammad K. SHARBATDAR,Genda CHEN,Lesley SNEED

期刊论文

AGRI-ENVIRONMENTAL ASSESSMENT OF CONVENTIONAL AND ALTERNATIVE BIOENERGY CROPPING SYSTEMS PROMOTING BIOMASS

期刊论文

Recent transmission of Mycobacterium tuberculosis in China: the implication of molecular epidemiology

null

期刊论文

Robotic distal pancreatectomy versus conventional laparoscopic distal pancreatectomy: a comparative study

null

期刊论文

Antibiotic resistome mostly relates to bacterial taxonomy along a suburban transmission chain

期刊论文

Planet position errors in planetary transmission: Effect on load sharing and transmission error

Miguel IGLESIAS, Alfonso FERNáNDEZ, Ana DE-JUAN, Ramón SANCIBRIáN, Pablo GARCíA

期刊论文

Eliminating mother-to-child transmission of HBV: progress and challenges in China

Wenzhan Jing, Jue Liu, Min Liu

期刊论文

An approach for evaluating the impact of an intermittent renewable energy source on transmission expansion

Rongrit CHATTHAWORN,Surachai CHAITUSANEY

期刊论文