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Advancing hemostasis:A meta-analysis of novel vs conventional endoscopic therapies for non variceal upper gastrointestinal bleeding
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作者 Shivangini Duggal Ishana Kalra +1 位作者 Keisha Kalra Vicky Bhagat 《World Journal of Gastrointestinal Endoscopy》 2025年第6期107-119,共13页
BACKGROUND Non variceal upper gastrointestinal bleeding(NVUGIB)is a life-threatening condition requiring prompt and effective hemostasis.Various endoscopic inter-ventions,including novel hemostatic powders(HP),over-th... BACKGROUND Non variceal upper gastrointestinal bleeding(NVUGIB)is a life-threatening condition requiring prompt and effective hemostasis.Various endoscopic inter-ventions,including novel hemostatic powders(HP),over-the-scope clips(OTSC),and traditional approaches,have been employed to manage upper gastroin-testinal bleeding(UGIB).Despite advancements,comparative efficacy and safety of these modalities remain uncertain.AIM To evaluate the efficacy and safety of novel hemostatic interventions compared to conventional endoscopic techniques for managing UGIB.METHODS Cochrane,MEDLINE,PubMed and Scopus libraries were searched for rando-mized controlled trials(RCTs)published up to October 2024.Only RCTs compa-ring novel interventions,such as HP or OTSC,with conventional endoscopic treatments computed tomography(CT)were included.The primary outcome was the 30-day rebleeding rate.Secondary outcomes included initial hemostasis,short-term rebleeding rates,need for salvage therapy(surgical/angiographic),30-day all-cause mortality,and bleeding-related mortality.We performed pairwise and network meta-analyses for all treatments.RESULTS Seventeen studies were included in this analysis.Regarding the 30-day rebleeding rate,OTSC and HP showed superior efficacy compared with CT[OTSC vs CT:Relative risk(RR):0.47,95%confidence interval(CI):0.33-0.65;HP vs CT:RR:0.73,95%CI:0.45-1.13],while OTSC and HP had comparable efficacy(RR:0.56,95%CI:0.30-1.05).OTSC ranked the highest in the network ranking estimate for this outcome.For the secondary outcomes,OTSC demonstrated superior efficacy for the short-term rebleeding rate(OTSC vs CT:RR:0.35,95%CI:0.14-0.74;HP vs CT:RR:0.62,95%CI:0.28-1.35;OTSC vs HP:RR:0.59,95%CI:0.17-1.67).Regarding the initial hemostasis rate,OTSC was slightly more effective than CT(OTSC vs CT:RR:1.20,95%CI:1.06-1.57)and comparable to HP(OTSC vs HP:RR:1.08,95%CI:0.89-1.40).There were no significant differences among treatments for all-cause mortality,bleeding-related mortality,or the necessity of surgical or angiographic salvage therapy.OTSC consistently ranked highest across most outcomes in the network ranking estimate. 展开更多
关键词 Hemostatic methods Non-variceal upper gastrointestinal bleeding Over-the-scope-clips conventional methods Hemostatic spray
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Nonvolatile Electrical Control of Transport Properties in Multiferroic OsCl_(2)/Sc_(2)CO_(2)Heterostructure
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作者 Shi-Xu Wang Shu-Xiang Qiao +4 位作者 Mei-Yan Ni Xiao-Hong Zheng Hua Hao Hong-Yan Lu Ping Zhang 《Chinese Physics Letters》 2025年第8期129-142,共14页
Ferromagnetic materials play an important role in memory materials,but conventional control methods are often limited by issues such as high power consumption and volatility.Multiferroic heterostructures provide a pro... Ferromagnetic materials play an important role in memory materials,but conventional control methods are often limited by issues such as high power consumption and volatility.Multiferroic heterostructures provide a promising alternative to achieve low power consumption and nonvolatile electric control of magnetic properties.In this paper,a two-dimensional multiferroic van der Waals heterostructure OsCl_(2)/Sc_(2)CO_(2),which is composed of ferromagnetic monolayer OsCl_(2)and ferroelectric monolayer Sc_(2)CO_(2),is studied by first-principles density functional theory.The results show that by reversing the direction of the electric polarization of Sc_(2)CO_(2),OsCl_(2)can be transformed from a semiconductor to a half-metal,demonstrating a nonvolatile electrical manipulation of the heterostructure through ferroelectric polarization.The underlying physical mechanism is explained by band alignments and charge density differences.Furthermore,based on the heterostructure,we construct a multiferroic tunnel junction with a tunnel electroresistance ratio of 3.38×10^(14)%and a tunnel magnetoresistance ratio of 5.04×10^(6)%,allowing control of conduction states via instantaneous electric or magnetic fields.The findings provide a feasible strategy for designing advanced nanodevices based on the giant tunnel electroresistance and tunnel magnetoresistance effects. 展开更多
关键词 nonvolatile electrical control conventional control methods multiferroic heterostructure oscl ferromagnetic materials sc Co ferromagnetic monolayer ferroelectric monolayer
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Conventional vs.modified pseudo-dynamic seismic analyses in the shallow strip footing bearing capacity problem 被引量:2
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作者 Ghazal Rezaie Soufi Reza Jamshidi Chenari Sina Javankhoshdel 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2021年第4期993-1006,共14页
The conventional pseudo-dynamic(CPD)and modified pseudo-dynamic(MPD)methods are invoked to obtain the seismic bearing capacity of strip foundations using the limit equilibrium method,with a two-wedge failure mechanism... The conventional pseudo-dynamic(CPD)and modified pseudo-dynamic(MPD)methods are invoked to obtain the seismic bearing capacity of strip foundations using the limit equilibrium method,with a two-wedge failure mechanism.A spectral version of the conventional pseudo-dynamic method(SPD)is also invoked by considering the ground motion amplification factor,to be a function of the non-dimensional frequencyλ/B and soil damping.Numeric analyses show that bearing capacity results obtained by the MPD and SPD methods are generally consistent.Both experience the same general reduction in bearing capacity with the increase ofλ/B,with successive ups and downs corresponding to soil′s natural frequencies.For 5<λ/B<10,SPD and MPD results fluctuated between falling above and below CPD results.Forλ/B<2.5,SPD and MPD results were consistent with attenuation of the shear wave,while for 10<λ/B,amplification was exhibited.Results obtained by the CPD method monotonically decrease,due to the fact that CPD fails to inherently consider site effects and damping,and instead and relies on a single factor to consider the ground motion amplification. 展开更多
关键词 bearing capacity modified pseudo-dynamic method conventional pseudo-dynamic method spectral analysis
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Comparative Analysis for Evaluating Wind Energy Resources Using Intelligent Optimization Algorithms and Numerical Methods
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作者 Musaed Alrashidi 《Computer Systems Science & Engineering》 SCIE EI 2023年第10期491-513,共23页
Statistical distributions are used to model wind speed,and the twoparameters Weibull distribution has proven its effectiveness at characterizing wind speed.Accurate estimation of Weibull parameters,the scale(c)and sha... Statistical distributions are used to model wind speed,and the twoparameters Weibull distribution has proven its effectiveness at characterizing wind speed.Accurate estimation of Weibull parameters,the scale(c)and shape(k),is crucial in describing the actual wind speed data and evaluating the wind energy potential.Therefore,this study compares the most common conventional numerical(CN)estimation methods and the recent intelligent optimization algorithms(IOA)to show how precise estimation of c and k affects the wind energy resource assessments.In addition,this study conducts technical and economic feasibility studies for five sites in the northern part of Saudi Arabia,namely Aljouf,Rafha,Tabuk,Turaif,and Yanbo.Results exhibit that IOAs have better performance in attaining optimal Weibull parameters and provided an adequate description of the observed wind speed data.Also,with six wind turbine technologies rating between 1 and 3MW,the technical and economic assessment results reveal that the CN methods tend to overestimate the energy output and underestimate the cost of energy($/kWh)compared to the assessments by IOAs.The energy cost analyses show that Turaif is the windiest site,with an electricity cost of$0.016906/kWh.The highest wind energy output is obtained with the wind turbine having a rated power of 2.5 MW at all considered sites with electricity costs not exceeding$0.02739/kWh.Finally,the outcomes of this study exhibit the potential of wind energy in Saudi Arabia,and its environmental goals can be acquired by harvesting wind energy. 展开更多
关键词 Weibull distribution conventional numerical methods intelligent optimization algorithms wind resource exploration and exploitation cost of energy($/kWh)
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CLINICAL OBSERVATION ON TREATMENT OF PERIPHERAL FACIAL PARALYSIS WITH DIFFERENT NEEDLING METHODS
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作者 胡幼平 杨运宽 《World Journal of Acupuncture-Moxibustion》 2002年第4期37-40,共4页
Purpose: To observe the clinical therapeutic effect of different needling methods in the treatment of peripheral facial paralysis. Methods: A total of 158 cases of peripheral facial palsy patients are randomly divided... Purpose: To observe the clinical therapeutic effect of different needling methods in the treatment of peripheral facial paralysis. Methods: A total of 158 cases of peripheral facial palsy patients are randomly divided into treatment group (n=116 cases, who are treated by penetration needling method) and control group (n=42 cases, who are treated with traditional acupuncture method). In treatment group, main acupoint pairs for penetration needling are Yangbai (GB 14) -Yuyao (EX-HN 4), Tongziliao (GB 1) -Taiyang (EX-HN 5), Jiache (ST 6) -Dicang (ST 4) and Chengjiang (CV 24) -Jiachengjiang (EX-HN) on the affected side, and in control group, the main acupoints used are Yifeng (TE 17), Yangbai (GB 14), Sibai (ST 2), Dicang (ST 4), Jiache (ST 6), Jingming (BL 1) and Chengjiang (CV 24). The treatment is given once daily with 10 sessions being a therapeutic course. Results: After 3 courses of treatment, the cure rates of treatment group and control group are 81.8% and 66.7% separately, showing a significant difference between two groups (P<0.05). The total effective rates of treatment and control groups are 96.5% and 88.1% separately, presenting a significant difference between two groups (P<0.01). Conclusion: The therapeutic effect of penetration needling method is better than that of traditional acupuncture method. 展开更多
关键词 Facial Paralysis Penetration needling method conventional acupuncture method
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Advances in the detec
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作者 Yingying Zhao Dandan Xia +3 位作者 Panpan Ma Xiaofeng Gao Wenyi Kang Jinfeng Wei 《Food Science and Human Wellness》 SCIE 2020年第1期40-44,共5页
Human health is threatened by foodborne illness and Staphylococcus aureus is a common foodborne pathogenic bacteria.It can cause food poisoning when we are infected,therefore,it is necessary to detect pathogenic bacte... Human health is threatened by foodborne illness and Staphylococcus aureus is a common foodborne pathogenic bacteria.It can cause food poisoning when we are infected,therefore,it is necessary to detect pathogenic bacteria.The virulence genes and detection methods of S.aureus are summarized from literatures.Traditional detection methods are simple but need bacteria enrichment and to prolong detection time.Immunological technology has high specificity,but false positive results are easy to occur in its detection.In recent years,molecular biology methods have developed rapidly,and various PCR techniques have been applied to detect foodborne pathogens.Real-time fluorescent quantitative PCR is more effective than ordinary PCR,while price is expensive when use it,the scope of use is limited.LAMP is a flexible detection method,biosensor and flow cytometry are fast but the cost of detection is high and the price is relatively expensive. 展开更多
关键词 Staphylococcus aureus Virulence genes conventional methods Rapid detection methods
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A pilot randomized control study to evaluate endoscopic resection using a ligation device for rectal carcinoid tumors 被引量:3
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作者 Hiroyuki Sakata Ryuichi Iwakiri +10 位作者 Akifumi Ootani Seiji Tsunada Shinichi Ogata Hibiki Ootani Ryo Shimoda Kanako Yamaguchi Yasuhisa Sakata Sadahiro Amemori Kotaro Mannen Masanobu Mizuguchi Kazuma Fujimoto 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第25期4026-4028,共3页
AIM: Rectal carcinoid tumors smaller than 10 mm can be resected with local excision using endoscopy. In order to remove rectal carcinoid tumors completely, we evaluated endoscopic mucosal resection with a ligation de... AIM: Rectal carcinoid tumors smaller than 10 mm can be resected with local excision using endoscopy. In order to remove rectal carcinoid tumors completely, we evaluated endoscopic mucosal resection with a ligation device in this pilot control randomized study. METHODS: Fifteen patients were diagnosed with rectal carcinoid tumor (less than 10 mm) in our hospital from 1993 to 2002. There were 9 males and 6 females, with a mean age 61.5 years (range, 34-77 years). The patientshad no complaints of carcinoid syndrome symptoms. Fifteen patients were randomly divided into 2 groups: 7 carcinoid tumors were treated by conventional endoscopic resection, and 8 carcinoid tumors were treated by endoscopic resection using a ligation device. RESULTS: All rectal carcinoid tumors were located at the middle to distal rectum. The size of the tumors varied from 3 mm to 10 mm and background characteristics of the patients were not different in the two groups. The rate of complete removal of carcinoid tumors using a ligation device (100%, 8/8) was significantly higher than that of conventional endoscopic resection (57.1%, 4/7). The three patients had tumor involvement of deep margin, for which additional treatment was performed. No complications occurred during or after endoscopic resection using a ligation device. All patients in the both groups were alive during the 3-year observation period. CONCLUSION: Endoscopic resection using a ligation device is a useful and safe method for resection of small rectal carcinoid tumors. 展开更多
关键词 CARCINOID Ligation mucosectomy ENDOSCOPY RECTUM conventional method
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Using DGT to Assess Cadmium Bioavailability to Ryegrass as Influenced by Soil Properties 被引量:1
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作者 SONG Ningning WANG Fangli +1 位作者 MA Yibing TANG Shirong 《Pedosphere》 SCIE CAS CSCD 2015年第6期825-833,共9页
A generally accepted method for predicting the bioavailability and transfer of cadmium(Cd) from soil to plants has not yet been established. In this study, the diffusive gradients in thin films(DGT) and conventional e... A generally accepted method for predicting the bioavailability and transfer of cadmium(Cd) from soil to plants has not yet been established. In this study, the diffusive gradients in thin films(DGT) and conventional extraction methods for metal fractions were used to investigate how effective these methods were at predicting Cd bioavailability to ryegrass(Lolium perenne) and to assess whether these holistic variables were independent of the soil property variables. The influences of soil properties on the predictive capabilities of the different methods were evaluated using multivariate statistics. The Cd concentrations in the shoots and roots of ryegrass correlated more closely with the effective Cd concentration measured by DGT(CE), compared with those with soil total Cd, pore water Cd, and ethylenediaminetetraacetic acid disodium salt(Na2EDTA)- and acetic acid(HOAc)-extractable Cd. When soil properties were included in a stepwise multiple linear regression, Cd transfer to L. perenne was negatively influenced by p H and positively influenced by organic matter(OM). The multivariate statistics showed that the adjusted correlation coefficients for the plots involving soil total Cd, pore water Cd, and Na2EDTA- and HOAc-extractable Cd had been significantly improved after considering the influences of soil properties, which suggested that these methods were p H and OM dependent. For CE, the relationship was p H independent or only dependent in strongly acidic soils. These results suggested that the main soil factors affecting bioavailability had the lowest impact on the DGT technique. Therefore, the DGT technique provided significant advantages over conventional methods when assessing Cd bioavailability. 展开更多
关键词 conventional extraction methods diffusive gradients in thin films effective Cd concentration organic matter pore water
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A new design of groundwater sampling device and its application
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作者 Yih-Jin Tsai Ming-Ching T. Kuo 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第5期838-841,共4页
Compounds in the atmosphere contaminate samples of groundwater. An inexpensive and simple method for collecting groundwater samples is developed to prevent contamination when the background concentration of contaminan... Compounds in the atmosphere contaminate samples of groundwater. An inexpensive and simple method for collecting groundwater samples is developed to prevent contamination when the background concentration of contaminants is high. This new design of groundwater sampling device involves a glass sampling bottle with a Teflon-lined valve at each end. A cleaned and dried sampling bottle was connected to a low flow-rate peristaltic pump with Teflon tubing and was filled with water. No headspace volume was remained in the sampling bottle. The sample bottle was then packed in a PVC bag to prevent the target component from infiltrating into the water sample through the valves. In this study, groundwater was sampled at six wells using both the conventional method and the improved method. The analysis of trichlorofluoromethane( CFC-11 ) concentrations at these six wells indicates that all the groundwater samples obtained by the conventional sampling method were contaminated by CFC-11 from the atmosphere. The improved sampling method greatly eliminated the problems of contamination, preservation and quantitative analysis of natural water. 展开更多
关键词 groundwater sampling improved method conventional method tritium trichlorofluoromethane(CFC-11
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Microbial Limit Test of Zhideke Granules
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作者 Yunjuan PANG Yushan ZHOU +4 位作者 Jie LIANG Hui XU Jinyu WEI Dongfang HUANG Zhengyi SUN 《Medicinal Plant》 CAS 2021年第3期72-74,共3页
[Objectives]To test the microbial limit of Zhideke granules.[Methods]According to the relevant regulations on the testing of granules in Chinese Pharmacopoeia in 2015,the applicability of the methods for counting the ... [Objectives]To test the microbial limit of Zhideke granules.[Methods]According to the relevant regulations on the testing of granules in Chinese Pharmacopoeia in 2015,the applicability of the methods for counting the total number of aerobic bacteria,molds and yeasts and objectionable organisms in Zhideke granules was studied.[Results]The total number of aerobic bacteria in Zhideke granules was determined by dilution plate method(1∶20,1 mL per dish),the total number of molds and yeasts was determined by conventional plate method(1∶10,1 mL per dish),and E.coli was detected by conventional method of TTB(1∶10 test solution,10-100 mL TSB).[Conclusions]The method was suitable for the microbial limit test of Zhideke granules. 展开更多
关键词 Zhideke granule Microbial limit Methodological verification Aerobic bacteria MOLD YEAST Plate method conventional method E.COLI
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Efficiency of locally available filter media on fluoride and phosphate removal for household water treatment system
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作者 Mekonnen Birhane Alebel Abebe +1 位作者 Esayas Alemayehu Embialle Mengistie 《Chinese Journal of Population,Resources and Environment》 2014年第2期110-115,共6页
Since conventional water treatment is not affordable in developing countries,looking for locally available and alternative treatment options is mandatory.Removal of fluoride and phosphate can be achieved by designing ... Since conventional water treatment is not affordable in developing countries,looking for locally available and alternative treatment options is mandatory.Removal of fluoride and phosphate can be achieved by designing appropriate filtration media from different materials such as sand,calcined clay,pumice,scoria and bone char.This study was designed to determine the removal efficiency of these locally available filter media with respect to detention time and pH.The filtration apparatuses(tank) were filled separately with stone,gravel with grain size 0.6-4.75 mm and 40 cm deep,sand(ES = 0.15—0.35 mm and UC = 1.5-3),calcined clay,pumice,scoria and bone char with grain size 0.25-0.5 inch.Water samples were prepared using glass bottles with fluoride concentrations of 6 and 8 mg/1 and phosphate concentration of 4 mg/1.Laboratory analysis was carried out before and after filtration to determine the removal efficiency of each medium.It was found that the highest removal of fluoride was achieved by bone char(89.65%),followed by pumice(82.4%).However,bone char has rather increased the concentration of phosphate by 63.8%.Sand was the most efficient media to remove phosphate,managing to remove by 70%.Therefore,it is an attractive option to use these locally available,environmental friendly and appropriate technologies for efficient removal of both fluorine and phosphate at the household or community water treatment level. 展开更多
关键词 conventional water treatment methods chemical impurities filter medium detention time reduction potential fluoridated water
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Advances in Breeding of Festuca arundinacea Schreb.
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作者 Jiahai WU Xiaoli WANG +2 位作者 Wei FU Qiong MU Chunyan YANG 《Agricultural Biotechnology》 CAS 2013年第6期33-38,43,共7页
In this paper, domestic and foreign advances in breeding situation and conventional breeding methods of Festuca arundinacea Schreb. and the applica- tion of modem biological techniques ( somaclonal variation, somatic... In this paper, domestic and foreign advances in breeding situation and conventional breeding methods of Festuca arundinacea Schreb. and the applica- tion of modem biological techniques ( somaclonal variation, somatic cell hybridization, genetic map construction, genetic diversity, gene cloning and expression, ge- netic engineering) in breeding of new varieties of F. arundinacea were summarized, which proposed new ideas for the development of F. arundinacea breeding and provided reference for breeding of new varieties of F. arundinacea. 展开更多
关键词 Festuca arundinacea Schreb. Breeding situation conventional breeding methods Modern biological techniques
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Expert consensus on digital restoration of complete dentures
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作者 Yue Feng Zhihong Feng +25 位作者 Jing Li Jihua Chen Haiyang Yu Xinquan Jiang Yongsheng Zhou Yumei Zhang Cui Huang Baiping Fu Yan Wang Hui Cheng Jianfeng Ma Qingsong Jiang Hongbing Liao Chufan Ma Weicai Liu Guofeng Wu Sheng Yang Zhe Wu Shizhu Bai Ming Fang Yan Dong Jiang Wu Lin Niu Ling Zhang Fu Wang Lina Niu 《International Journal of Oral Science》 2025年第5期597-607,共11页
Digital technologies have become an integral part of complete denture restoration.With advancement in computer-aided design and computer-aided manufacturing(CAD/CAM),tools such as intraoral scanning,facial scanning,3D... Digital technologies have become an integral part of complete denture restoration.With advancement in computer-aided design and computer-aided manufacturing(CAD/CAM),tools such as intraoral scanning,facial scanning,3D printing,and numerical control machining are reshaping the workflow of complete denture restoration.Unlike conventional methods that rely heavily on clinical experience and manual techniques,digital technologies offer greater precision,predictability,and efficacy.They also streamline the process by reducing the number of patient visits and improving overall comfort.Despite these improvements,the clinical application of digital complete denture restoration still faces challenges that require further standardization.The major issues include appropriate case selection,establishing consistent digital workflows,and evaluating long-term outcomes.To address these challenges and provide clinical guidance for practitioners,this expert consensus outlines the principles,advantages,and limitations of digital complete denture technology.The aim of this review was to offer practical recommendations on indications,clinical procedures and precautions,evaluation metrics,and outcome assessment to support digital restoration of complete denture in clinical practice. 展开更多
关键词 manual techniquesdigital conventional methods numerical control machining clinical experience denture restorationunlike intraoral scanningfacial scanning d printingand denture restorationwith digital technologies
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Fabrication of scaffolds in tissue engineering: A review 被引量:7
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作者 Peng ZHAO Haibing GU +3 位作者 Haoyang MI Chengchen RAO Jianzhong FU Lih-sheng TURNG 《Frontiers of Mechanical Engineering》 SCIE CSCD 2018年第1期107-119,共13页
Tissue engineering (TE) is an integrated discipline that involves engineering and natural science in the development of biological materials to replace, repair, and improve the function of diseased or missing tissue... Tissue engineering (TE) is an integrated discipline that involves engineering and natural science in the development of biological materials to replace, repair, and improve the function of diseased or missing tissues. Traditional medical and surgical treatments have been reported to have side effects on patients caused by organ necrosis and tissue loss. However, engineered tissues and organs provide a new way to cure specific diseases. Scaffold fabrication is an important step in the TE process. This paper summarizes and reviews the widely used scaffold fabrication methods, including conventional methods, electrospinning, three-dimensional printing, and a combination of molding techniques. Furthermore, the differences among the properties of tissues, such as pore size and distribution, porosity, structure, and mechanical properties, are elucidated and critically reviewed. Some studies that combine two or more methods are also reviewed. Finally, this paper provides some guidance and suggestions for the future of scaffold fabrication. 展开更多
关键词 tissue engineering scaffolds electrospinning 3D printing molding techniques conventional methods
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Extraction of distributed parameters for multi-conductor transmission lines by the difference iteration method
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作者 Yang Li Lu Guizhen 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2018年第5期93-100,共8页
The distributed parameters of the transmission lines have the significant impact to the signal propagation. In the conventional method of the distributed parameter extraction,the discontinuity of inverse trigonometric... The distributed parameters of the transmission lines have the significant impact to the signal propagation. In the conventional method of the distributed parameter extraction,the discontinuity of inverse trigonometric or hyperbolic can arise the problem about phase ambiguity which causes significant errors for transmission models. A difference iteration method( DIM) is proposed for extracting distributed parameters of high frequency transmission line structure in order to overcome the phase ambiguity in the conventional method( CM). The formulations of the proposed method are first derived for two-conductor and multi-conductor lines. Then the validation is performed for the models of micro-strip transmission line. Numerical results demonstrate that the proposed DIM can solve the problem about the phase ambiguity and the extracted distributed parameters are accurate and efficient for a wide range of the frequencies of interest and line lengths. 展开更多
关键词 two-conductor transmission line multi-conductor transmission line conventional method difference iteration method distributed parameters
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Fast Energy Detection for Ultra-multilayered Anisotropic Media Based on Transfer Matrix Method in Terahertz Region
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作者 Jiuyang Fan Qing Huo Liu +1 位作者 Zhixiang Huang Yuxian Zhang 《Electromagnetic Science》 2025年第3期79-92,共14页
In this article,the ultra-efficient transfer matrix method(U-TMM)is developed to detecting the propagation coeffi-cients of ultra-multilayered anisotropic media(UMAM)in the terahertz region.Starting from the curl Maxw... In this article,the ultra-efficient transfer matrix method(U-TMM)is developed to detecting the propagation coeffi-cients of ultra-multilayered anisotropic media(UMAM)in the terahertz region.Starting from the curl Maxwell’s equations and combined with the constitutive relation,the governing equation can be described in matrix form from which the four eigenvalues are derived,so that each component of the electromagnetic field can be uniquely represented by the fixed formula.The core thought with U-TMM is to maintain tangential continuity of electromagnetic fields between different media,thereby constructing transfer matrix between various regions and achieving the calculation of propagation coefficients in UMAM.After successfully validating U-TMM through two numerical examples,we find that U-TMM compensates for the shortcomings of COMSOL software in dealing with the UMAM problems,and in addition,the computational efficiency is significantly improved compared to the conventional transfer matrix method.Finally,to verify the energy change process in UMAM,we generate color images of the propagation coeffi-cients by U-TMM in transverse electric/transverse magnetic mode,which can be applied to the analysis for materials and devices in the terahertz region. 展开更多
关键词 Ultra-efficient transfer matrix method Ultra-multilayered anisotropic media Terahertz conventional transfer ma-trix method
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