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Fertility outcome analysis after modified laparoscopic microsurgical tubal anastomosis

null

《医学前沿（英文）》 2011年第5卷第3期页码 310-314 doi: 10.1007/s11684-011-0152-8

摘要：

Modified laparoscopic microsurgical tubal anastomosis is an alternative for microsurgical anastomosis via laparotomy to reverse sterilization in women with renewed child wish. The current study aims to evaluate the fertility outcome after modified laparoscopic microsurgical tubal anastomosis. A retrospective study was performed. Fifty-eight women who underwent modified laparoscopic microsurgical tubal anastomosis were monitored to investigate the fertility outcome and characteristics of this new technology. Of the 58 patients, the cumulative pregnancy rate (PR) in the 42 patients with follow-up data was 23.8% (10/42), 57.1% (24/42), 66.7% (28/42), and 73.8% (31/42) within 6, 12, 24, and 36 months after surgery, respectively. The intrauterine PR was 69.0% (29/42). Two patients (4.8%) had ectopic pregnancies that occurred within 24 months of surgery; three cases ended in spontaneous abortion. The delivery rate was 83.9% (26/31). The length of operating time was 1.2±0.3 h, with a range of 1.0–2.5 h (60–145 min), and the mean time was approximately 75 min. The blood loss was relatively small, between 10 and 50 ml with an average amount of 22 ml. Thus, the modified laparoscopic tubal anastomosis is a highly successful procedure and a viable alternative to open abdominal microsurgical approaches. Compared with the traditional laparoscopic tubal sterilization reversal, this modified approach has three advantages: (1) less invasive approach via a trocar reduction; (2) remodeling of tube is better performing tied together after 3–4 sutures; and (3) faster operating time.

关键词： modified laparoscopy tubal anastomosis microsurgery

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宫腔镜、腹腔镜治疗剖宫产瘢痕妊娠72例分析

李长东,冯颖,陈素文,聂东云,李坚,张为远

《中国工程科学》 2014年第16卷第5期页码 20-23

摘要：

为了探讨宫腔镜和腹腔镜手术治疗剖宫产瘢痕妊娠（CSP）的指证及技术要点。回顾性地分析了首都医科大学附属北京妇产医院2013 年1 月—2013 年12 月收治的72 例CSP患者的治疗情况。所有患者入院后行血清人绒毛膜促性腺激素（HCG）测定和三维彩超检查。根据局部病灶范围、HCG结果和多普勒B超血流结果，术前选择性行子宫动脉栓塞介入治疗或甲氨蝶呤治疗后，进一步行宫腔镜、腹腔镜或宫腹联合手术治疗。结果显示，30 例采用超声监测下宫腔镜CSP病灶切除术，12 例采用腹腔镜监护下宫腔镜CSP病灶切除术，30 例采用宫腹腔镜联合CSP病灶切除+剖宫产瘢痕修补术，均收到了良好的治疗效果。术中出血量为（83±57）mL，术后肛门排气时间为（20±6.6）h，阴道流血时间为（3.2±4.8）d，血清HCG降至正常时间为（8.6±3.9）d，出院时间为（3.2±2.0）d。患者术后病理诊断与术前的CSP诊断符合率达到100 %。研究得出，有剖宫产史的妇女再次妊娠时，有发生CSP的可能。超声或腹腔镜监护下宫腔镜CSP病灶切除术是治疗CSP的有效措施，病灶切除确切，创伤小；宫、腹腔镜CSP病灶切除+剖宫产瘢痕修补术在切除病灶，对后续有生育要求患者同时修复剖宫产瘢痕处解剖学异常，降低了再次妊娠时CSP和子宫破裂、胎盘植入等产科并发症的风险。

关键词：剖宫产瘢痕妊娠宫腔镜腹腔镜

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Regulatory issues for genetically modified animals

Perry Bradbury HACKETT

《农业科学与工程前沿（英文）》 2020年第7卷第2期页码 188-203 doi: 10.15302/J-FASE-2019307

摘要：

Precision genetics and breeding have the potential to meet the agricultural needs and goals of the world in the 21st century. These needs include increasing the efficiency of production of animals and improving their products with minimal impact on the environment. The USA is the major innovator in genomic science and the acknowledged leader in formulating policies to regulate genetic applications in medicine and agriculture. However, governments worldwide have been exceedingly reluctant to support the introduction of genetically modified (GM) animals into agriculture. Regulatory policies have stagnated due to legal guidelines that could not anticipate the needs and solutions that are evident today. This must change if we are to maintain planetary integrity. I propose a new, market-based regulatory model for GM livestock that has both a strong scientific foundation and has worked for 10000 years. The model is similar to that for information technology in which specific algorithms drive computer and cell phone applications. Genome engineers write genetic algorithms that drive the traits in biological organisms. Accordingly, GM products should be viewed in terms of their use and public benefit rather than by limitations to the genetic programing coming from a few highly vocal groups. Genetic algorithms (Genapps) of the 21st century will include not only introduction of synthetic genes, but also complete natural and synthetic biochemical pathways to produce agricultural products that are maximally efficient, healthy to humans and animals, and sustainable in an era of changing climates while avoiding environmental degradation.

关键词： algorithms editing FDA GMO recombinant DNA USDA

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Tuned reactive power dispatch through modified differential evolution technique

S. BISWAS (RAHA), N. CHAKRABORTY

《能源前沿（英文）》 2012年第6卷第2期页码 138-147 doi: 10.1007/s11708-012-0188-8

摘要： This paper explores the capability of modified differential evolution (MDE) technique for solving the reactive power dispatch (RPD) problem. The proposed method is based on the basic differential evolution (DE) technique with a few modifications made into it. DE is one of the strongest optimization techniques though it suffers from the problem of slow convergence while global minima appear. The proposed modifications are tried to resolve the problem. The RPD problem mainly defines loss minimization with stable voltage profile. To solve the RPD problem, the generator bus voltage, transformer tap setting and shunt capacitor placements are controlled by the MDE approach. In this paper, IEEE 14-bus and IEEE 30-bus systems are chosen for MDE implementation. The applied modification show much improved result in comparison to normal DE technique. Comparative study with other soft-computing technique including DE validates the effectiveness of the proposed method.

关键词： reactive power dispatch (RPD) modified differential evolution (MDE) differential evolution algorithm with localizations around the best vector (DELB)

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Current progress on natural orifice transluminal endoscopic surgery (NOTES)

null

《医学前沿（英文）》 2012年第6卷第2期页码 187-194 doi: 10.1007/s11684-012-0198-2

摘要：

Natural orifice transluminal endoscopic surgery (NOTES) has received considerable interest in recent years as a novel surgical technique. Here, we aim to review the current progress on NOTES, particularly focusing on the advantages and complications related to NOTES, the recent advances of surgical approaches, new instruments for closure of the natural orifice incision, and the newly developed platform for NOTES. Finally, we make a prediction of the conceivable applications of NOTES on human subjects.

关键词： natural orifice transluminal endoscopic surgery (NOTES) laparotomy laparoscopy

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Approaching the binding between Cu(II) and aerobic granules by a modified titration and µ-XRF

Hongwei LUO,Longfei WANG,Zhonghua TONG,Hanqing YU,Guoping SHENG

《环境科学与工程前沿（英文）》 2016年第10卷第2期页码 362-367 doi: 10.1007/s11783-015-0803-0

摘要： Interactions between metals and activated sludge can substantially affect the fate and transport of heavy metals in wastewater treatment plants. Therefore, it is important to develop a simple, fast and efficient method to elucidate the interaction. In this study, a modified titration method with a dynamic mode was developed to investigate the binding of Cu(II), a typical heavy metal, onto aerobic granules. The titration results indicated that pH and ionic strength both had a positive effect on the biosorption capacity of the granular sludge. The -XRF results demonstrated that the distribution of metals on the granular surface was heterogeneous, and Cu showed strong correlations and had the same “hot spots” positions with other metal ions (e.g., Ca, Mg, Fe etc.). Ion exchange and complexing were the main mechanisms for the biosorption of Cu(II) by aerobic granules. These results would be beneficial for better understanding of Cu(II) migration and its fate in wastewater treatment plants.

关键词： aerobic granules Cu(II) modified titration µ-XRF analysis

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Kinetics and thermodynamics of the phosphine adsorption on the modified activated carbon

Bingnan REN

《化学科学与工程前沿（英文）》 2011年第5卷第2期页码 203-208 doi: 10.1007/s11705-010-0571-0

摘要： The kinetics and the thermodynamics of phosphine (PH ) adsorption on the modified activated carbon have been explained for the adsorption process of PH . This study investigated the kinetic and thermodynamic properties of PH adsorption on the activated carbon impregnated with 5% HCl solution. The thermodynamic properties including PH adsorption isotherm and adsorption heat were separately investigated at 20°C, 70°C, 90°C. The results showed that the Freundlich-type isotherm equation described the isotherms well. The adsorption capacity increased with increasing temperature between 20°C and 70°C. Between 70°C and 90°C, the adsorption capacity decreased obviously with increasing temperature. The adsorption capacity reached the maximum at 70°C. By analyzing the results of the kinetics and the thermodynamics, we found that the adsorption of PH was dominated by physical adsorption at the lower temperature (20°C). Then with increasing temperature, chemical adsorption gradually dominated in the adsorption process. The adsorption capacity decreased at above 70°C is due to the exothermic effects in the process of adsorption.

关键词： adsorption PH₃ activated carbon kinetics thermodynamics

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Removing phosphorus from aqueous solutions by using iron-modified corn straw biochar

Fenglin LIU,Jiane ZUO,Tong CHI,Pei WANG,Bo YANG

《环境科学与工程前沿（英文）》 2015年第9卷第6期页码 1066-1075 doi: 10.1007/s11783-015-0769-y

摘要： Iron-modified corn straw biochar was used as an adsorbent to remove phosphorus from agricultural runoff. When agricultural runoffs with a total phosphorus (TP) concentration of 1.86 mg·L to 2.47 mg·L were filtered at a hydraulic retention time of 2 h through a filtration column packed with the modified biochar, a TP removal efficiency of over 99% and an effluent TP concentration of less than 0.02 mg·L were achieved. The isotherms of the phosphorus adsorption by the modified biochar fitted the Freundlich equation better than the Langmuir equation. The mechanism of the phosphorus adsorbed by the modified biochar was analyzed by using various technologies, i.e. scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis, X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR). The results indicated that the surface of the modified biochar was covered by small iron granules, which were identified as Fe O . The results also showed that new iron oxides were formed on the surface of the modified biochar after the adsorption of phosphorus. Moreover, new bonds of Fe-O-P and P-C were found, which suggested that the new iron oxides tend to be Fe (PO ) (OH) . Aside from removing phosphorus, adding the modified biochar into soil also improved soil productivity. When the modified biochar-to-soil rate was 5%, the stem, root, and bean of broad bean plants demonstrated increased growth rates of 91%, 64%, and 165%, respectively.

关键词： iron-modified biochar phosphorus removal agricultural waste agricultural runoff

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Immobilization of penicillin G acylase onto amino-modified silica hydrogel

Weibing Dong, Huining HE, Junbo Gong, Victor C. YANG,

《化学科学与工程前沿（英文）》 2010年第4卷第1期页码 87-90 doi: 10.1007/s11705-009-0298-y

摘要： Amino-modified silica hydrogel (N-MSHG) was prepared by a simple sol-gel processing via the co-condensation of commercial silica sol with 3-aminopropyltrie-oxysilane. Penicillin G acylase (PGA), a model enzyme, was covalently immobilized onto the N-MSHG and then was used for the enzymatic synthesis of amoxicillin. The samples were characterized by Nitrogen sorption analysis, FT-IR and thermal gravimetric analysis (TGA). The results showed that the amino-modified gel was a mesoporous material with an average pore size of 12.64±0.17nm. The immobilization process was efficient and the immobilized enzyme showed high catalytic efficiency. The yield of the synthesis of amoxicillin in aqueous media was 38% for 2.5h. This sol-gel preparation is simple and shows prominent potential value in industrial processing.

关键词： gravimetric amino-modified efficient Amino-modified amoxicillin

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Phosphorous removal from wastewater by lanthanum modified Y zeolites

Weikang ZHANG, Ye TIAN

《化学科学与工程前沿（英文）》 2015年第9卷第2期页码 209-215 doi: 10.1007/s11705-014-1448-4

摘要： The adsorption capacities of Y zeolite and La (III)-modified Y zeolite were studied. A series of La(III)-modified Y zeolites with different La/Y zeolite mass ratios were characterized by X-ray diffraction, X-ray fluorescence and Brunauer-Emmett-Teller surface area analysis. Batch experiments were conducted to evaluate the effects of various experimental parameters, such as pH, ionic strength, coexisting anions ( , Cl , and ) and temperature, on the phosphate adsorption. The capacity of the La (III)-modified Y zeolite to remove phosphate increased as the La/Y zeolite mass ratio increased and after 4 h, a phosphate removal efficiency of 95% was achieved for a La/Y zeolite mass ratio of 0.10. The equilibrium adsorption isotherm data correlated better to the Langmuir model than the Freundlich model and the data followed a pseudo-second-order kinetic equation.

关键词： phosphate removal wastewater lanthanum impregnation Y zeolites

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Outdoor aging of road asphalt and SBS modified asphalt

Li XIANG, Juan TU, Jian CHENG, Guohe QUE

《化学科学与工程前沿（英文）》 2011年第5卷第1期页码 35-42 doi: 10.1007/s11705-010-0551-4

摘要： The process of performance degradation of road asphalt (RA) is regarded as aging. At present, better understanding of the thermal-oxidative aging of asphalt is achieved and the corresponding method to evaluate this process is developed; meanwhile, photo-oxidative aging (aging in an atmospheric environment, which is referred to as “outdoor aging” in this paper) of asphalt remains at the initial stages of scientific exploration. The outdoor natural ultraviolet (UV) aging of RA and SBS modified asphalt (SBSMA) are investigated in this study. The experimental results show that the basic performances of RA and SBSMA present similar change tendencies. The softening point increased, while the penetration and ductility decreased as the outdoor aging time passed by, and the 5°C ductility (ductility measured at 5°C) of SBSMA decreased very quickly. The group components of RA and SBSMA also change during UV aging. The content of asphaltene rose and that of aromatics and saturates decreased, while the content of resins changed insignificantly. Moreover, the Fourier transform infrared (FTIR) graphs show that the content of sulfoxide and carbonyl groups in RA and SBSMA increased significantly during the outdoor aging process.

关键词： asphalt SBS modified road asphalt outdoor aging ultraviolet

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Estimation of thermodynamic properties of the ternary molten salt system, LiF-NaF-BeF2, by the modified

ZHANG Dalin, QIU Suizheng, SU Guanghui, JIA Dounan

《能源前沿（英文）》 2007年第1卷第2期页码 174-180 doi: 10.1007/s11708-007-0022-x

摘要： The molten salt reactor (MSR), which is one of the generation IV reactors, can meet the demand of transmutation and breeding. The thermodynamic properties of the molten salt system like LiF-NaF-BeF2 influence the design and construction of the fuel salt and coolant in the MSR for the new generation. In this paper, the equation of state of the ternary system 15%LiF-58%NaF-27%BeF, over the temperature range from 873.15 to 1 073.15 K at one atmosphere pressure, is described using a modified Peng-Robinson (PR) equation. The densities of the ternary system and its components are estimated by this equation directly, and compared with the experimental data. Based on the equation of state, the other thermodynamic properties such as the enthalpy, entropy and heat capacity at constant pressure are estimated by the residual function method and the fugacity coefficient method respectively. The densities calculated by PR equation are highly in agreement with the experimental data, and the enthalpy, entropy and heat capacity evaluated by the two different methods are consistent with each other. It can be concluded that the modified PR equation can be applied to evaluate the density of the molten salt system, and it is recommended that it be used as the basis to estimate the enthalpy, entropy and heat capacity of the molten salt system.

关键词： modified Peng-Robinson coolant consistent MSR entropy

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Gold modified cobalt-based Fischer-Tropsch catalysts for conversion of synthesis gas to liquid fuels

Alan J. McCue, Jura Aponaviciute, Richard P.K. Wells, James A. Anderson

《化学科学与工程前沿（英文）》 2013年第7卷第3期页码 262-269 doi: 10.1007/s11705-013-1334-5

摘要： The addition of Au as a promoter/modifier for alumina supported Co catalyst has been studied by combined high temperature, high pressure Fourier transform infrared (FTIR) and on-line gas chromatography. The combination of these tools permitted the state of the active catalyst surface to be monitored while following the elution of reaction products during the first 5–7 h on stream of the catalyst. The catalysts under study were a 10%Co/Al O and a 2.5%Au/10%Co/Al O Samples were characterised before use using Raman and temperature programmed reduction (TPR). During the initial stages of reaction, hydrocarbons were built up on the surface of the catalyst as monitored by FTIR and the nature and amount of these species were assessed in terms of CH /CH ratio and the density of these alkyl fragments by employing absorption coefficients for the individual components. The nature and reducibility of the Co particles were modified by the presence of Au while the later also shifted the CO/H balance by acting as an effective water-gas shift catalyst during the early stages of reaction. This characteristic was lost during reaction as a consequence of redistribution of the two metallic phases.

关键词： gold modified catalyst conversion of synthesis gas

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Adsorption of humic acid from aqueous solution on bilayer hexadecyltrimethyl ammonium bromide-modified

Yanhui ZHAN, Jianwei LIN, Yanling QIU, Naiyun GAO, Zhiliang ZHU

《环境科学与工程前沿（英文）》 2011年第5卷第1期页码 65-75 doi: 10.1007/s11783-010-0277-z

摘要： Surfactant-modified natural zeolites (SMNZ) with different coverage types were prepared by loading hexadecyltrimethyl ammonium bromide (HTAB) onto the surface of a natural zeolite. The adsorption behavior of humic acid (HA) on SMNZ was investigated. Results indicate that the adsorbent SMNZ exhibited a higher affinity toward HA than the natural zeolite. HA removal efficiency by SMNZ increased with HTAB loading. Coexisting Ca in solution favored HA adsorption onto SMNZ. Adsorption capacity decreased with an increasing solution pH. For typical SMNZ with bilayer HTAB coverage, HA adsorption process is well described by a pseudo-second-order kinetic model. The experimental isotherm data fitted well with the Langmuir model. Calculated maximum HA adsorption capacities for SMNZ with bilayer HTAB coverage at pH 5.5 and 7.5 were 63 and 41 mg·g , respectively. E2/E3 (absorbance at 250 nm to that at 365 nm) and E4/E6 (absorbance at 465 nm to that at 665 nm) ratios of the residual HA in solution were lower than that of the original HA solution. This indicates that the HA fractions with high polar functional groups, low molecular weight (MW), and aromaticity had a stronger tendency for adsorption onto SMNZ with bilayer HTAB coverage. Results show that HTAB-modified natural zeolite is a promising adsorbent for removal of HA from aqueous solution.

关键词： bilayer surfactant-modified zeolite hexadecyltrimethyl ammonium bromide (HTAB) adsorption humic acid (HA)

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Adsorption property of direct fast black onto acid-thermal modified sepiolite and optimization of adsorption

Chengyuan SU, Weiguang LI, Yong WANG

《环境科学与工程前沿（英文）》 2013年第7卷第4期页码 503-511 doi: 10.1007/s11783-012-0477-9

摘要： The adsorption of direct fast black onto acid-thermal modified sepiolite was investigated. Batch adsorption experiments were performed to evaluate the influences of experimental parameters such as initial dye concentration, initial solution pH and adsorbent dosage on the adsorption process. The three-factor and three-level Box-Behnken response surface methodology (RSM) was utilized for modeling and optimization of the adsorption conditions for direct fast black onto the acid-thermal modified sepiolite. The raw sepiolite was converted to acid-thermal modified sepiolite, and changes in the fourier transform infrared spectrum (FTIR) adsorption bands of the sample were noted at 3435 cm and 1427 cm . The zeolitic water disappeared and the purity of sepiolite was improved by acid-thermal modification. The decolorization rate of direct fast black adsorbed increased from 68.2% to 98.9% on acid-thermal modified sepiolite as the initial solution pH decreased from 10 to 2. When the adsorbent dosage reached to 2.5 g·L , 2.0 g·L , 1.5 g·L and 1.0 g·L , the decolorization rate was 90.3%, 86.7%, 61.0% and 29.8%, respectively. When initial dye concentration increased from 25 to 200 mg·L , the decolorization rate decreased from 91.9% to 60.0%. The RSM results showed that the interaction between adsorbent dosage and pH to be a significant factor. The optimum conditions were as follows: the adsorbent dosage 1.99 g·L , pH 4.22, and reaction time 5.2 h. Under these conditions, the decolorization rate was 95.1%. The three dimensional fluorescence spectra of direct fast black before and after treatment showed that the direct fast black was almost all adsorbed by the acid-thermal modified sepiolite.

关键词： direct fast black acid-thermal modified sepiolite adsorption response surface methodology