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Sound Absorption Properties of Discarded Feathers/Ethylene Vinyl Acetate Copolymer Thermoplastic Composite Materials 被引量:2
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作者 毕吉红 吕丽华 +3 位作者 钱永芳 叶方 王晓 魏春艳 《Journal of Donghua University(English Edition)》 EI CAS 2016年第4期540-544,共5页
The discarded feathers / ethylene vinyl acetate copolymer( EVA) thermoplastic composite materials was obtained with discarded feathers as reinforced material and EVA powders as matrix material by hot pressing method. ... The discarded feathers / ethylene vinyl acetate copolymer( EVA) thermoplastic composite materials was obtained with discarded feathers as reinforced material and EVA powders as matrix material by hot pressing method. Sound absorption properties were studied by changing mass ratio of discarded feathers and EVA,thickness of composite materials,hot pressing pressure and hot pressing temperature. It was found that the sound absorption properties of composite materials were good when the mass ratio of discarded feathers and EVA was 1: 1,thickness of composite materials was 30 mm,hot pressing pressure was 8 MPa,and hot pressing temperature was 80 ℃. Under the optimum conditions,the effect of composite density on sound absorption property was analyzed. In a certain range,the sound absorption property was enhanced with the decrease of the composite density.When the composite density was 0. 1g /cm^3, the maximum absorption coefficient was 0.96. Finally,the capillary theory was used to calculate the maximum sound absorption coefficient of discarded feathers / EVA thermoplastic composite materials. The good agreements of experimental results and calculated results proved the validity of the theoretical models. 展开更多
关键词 discarded feather absorption property theoretical analysis
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Bacterial leaching of discarded copper ores from Yongping, China 被引量:1
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作者 Muqing Qiu Genxuan Wang Zhuxia Shen 《Journal of University of Science and Technology Beijing》 CSCD 2005年第4期294-297,共4页
The elementary and phase analysis of discarded copper ores from Yongping of China has been performed. The experi- ments of extracting copper from the discarded copper ores were done with the mixed bacteria obtained th... The elementary and phase analysis of discarded copper ores from Yongping of China has been performed. The experi- ments of extracting copper from the discarded copper ores were done with the mixed bacteria obtained through a series of enrichment, separation, domestication and combination tests. The results show that in the process of bioleaching, the pH value rises at first and drops gradually. The Eh value keeps rising along with the time and the appropriate Eh value varying between 750 and 800 mV will benefit the bioleaching copper. The high concentration of ferric ions is detrimental to the bioleaching copper. The results of bioleaching copper are good. That is, the copper recovery is 31.8% after 27 days. 展开更多
关键词 BIOLEACHING discarded copper ores mixed bacteria
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How to Comprehensively Utilize the Discarded Fresh Tobacco Leaf ?
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作者 Xiqing LIU Weiping FENG +3 位作者 Zhifu XU Dongyang HU Zairan DENG Wenyu LI 《Asian Agricultural Research》 2015年第12期74-76,共3页
This paper aims to explore comprehensive utilization way of discarded fresh tobacco leaf. Based on modern tobacco demands on green,environmental protection and sustainable development,as well as actual situation of bi... This paper aims to explore comprehensive utilization way of discarded fresh tobacco leaf. Based on modern tobacco demands on green,environmental protection and sustainable development,as well as actual situation of biogas production facility in some villages of local tobacco area,this paper selects Longwan Village of Fengshiyan Town as the experimental site and explores the rational way of discarded fresh tobacco leaf biogas fermentation. Results show that cutting and fermentation of discarded fresh tobacco leaf before adding into biogas digester is conductive to improving p H in fermentation process,reducing crust amount,and effectively improving biogas production amount and rate. The study can provide reference for effective processing and rational utilization of discarded fresh tobacco leaf. 展开更多
关键词 discarded FRESH TOBACCO LEAF BIOGAS FERMENTATION Comprehensive UTILIZATION
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Effect of partial and complete replacement of soybean with discarded cashew nut (Anacardium occidentale L) on liver and stomach histology of Clarias gariepinus (Burchell, 1822) 被引量:1
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作者 Emmanuel O.Ogueji Stanley C.Iheanacho +2 位作者 Christian E.Mbah Abubakar J.Yaji Uchenna Ezemagu 《Aquaculture and Fisheries》 2020年第2期86-91,共6页
The need for replacement of highly priced soybean meal(SM)in fish diets with unconventional plant materials has become imperative for the sustainability of aquaculture production.This study addressed the effect of rep... The need for replacement of highly priced soybean meal(SM)in fish diets with unconventional plant materials has become imperative for the sustainability of aquaculture production.This study addressed the effect of replacing SM with discarded cashew nut meal(DCNM)on the liver and stomach histology in African catfish(Clarias gariepinus).Total 90 juveniles(24.83±1.52 g)were fed DCNM based diets,inclusion level of 0,50%and 100%.Fish were fed twice daily(8:00 a.m.–4:00 p.m.)at 5%body weight for 56 days.The histology of liver and the stomach were assessed.Histo-morphological changes of the liver tissue were moderate at 100%DCNM fed fish compared to 50%DCNM and control(0 DCNM).Photomicrograph of stomach of 50%DCNM fed fish showed normal histo-morphological features,while moderate to severe histological distortions were observed in the stomach of 100%DCNM fed fish.The findings of the present study showed that partial(50%)replacement of SM with DCNM had no adverse nutritional consequence while total(100%)replacement of SM with DCNM in the diet of C.gariepinus resulted to moderate histological distortions of the liver and stomach. 展开更多
关键词 African catfish discarded cashew nut meal Alternative protein source HISTOLOGY LIVER STOMACH
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In-vitro Developmental Potential of Single Blastomeres Derived from Day 3 Discarded Human Embryos
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作者 Dong-mei JI Yi-juan SUN Ai-jun ZHANG Xiao-wei LU Zhi-hong NIU Yun FENG 《Journal of Reproduction and Contraception》 CAS 2010年第1期1-8,共8页
Objective To investigate whether isolated blastomeres of discarded human embryos could develop into blastocysts cultured in vitro without zona pellucida. Methods Total discarded 60 embryos, which were not suitable for... Objective To investigate whether isolated blastomeres of discarded human embryos could develop into blastocysts cultured in vitro without zona pellucida. Methods Total discarded 60 embryos, which were not suitable for transplanting or freezing, were collected from 21 patients. Of 60 embryos, 10, 8, 24, 12, and 4 embryos were at 2-, 3-, 4-, 5- and 6-cell stage, respectively. These embryos were split by 0.5% protease combined with mechanical method. The resulting single blastomere was cultured individually, evaluated daily and counted blastocyst development. Pluripotency of inner cell mass (ICM) of the blastocyst was analyzed by the expression of alkaline phosphatase(AKP). Results A total of 229 single blastomeres were isolated from 60 embryos. Defining the day when the embryos were split as the first day (d 1). The majority of the blastomere- derived embryos followed the normal pattern of development with compaction on d 3 and cavitationon d 4 and developed into small blastocysts on d 5. Rates of division, compaction, cavity and expansion of single blastomeres from 4-cell embryos were higher than those in other groups (P 〈O.05), and AKP was expressed in ICM. Conclusion Some of the blastomeres from discarded human embryo are flexible and able to develop into blastocysts, the potential was related to their donor embryos closely. They seem to follow development pattern of their donor embryos. The blastomere- derived blastocysts have smaller size and fewer cells compared with regular in vitro cultured human embryos. However, AKP expression showed ICM cells with pluripotency. We believe that the value of single blastomere of discarded embryos will be further confirmed in the future. 展开更多
关键词 discarded embryo single blastomere in-vitro development
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Mesenchymal stromal cells from human perinatal tissues: From biology to cell therapy 被引量:16
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作者 Karen Bieback Irena Brinkmann 《World Journal of Stem Cells》 SCIE CAS 2010年第4期81-92,共12页
Cell-based regenerative medicine is of growing interest in biomedical research. The role of stem cells in this context is under intense scrutiny and may help to define principles of organ regeneration and develop inno... Cell-based regenerative medicine is of growing interest in biomedical research. The role of stem cells in this context is under intense scrutiny and may help to define principles of organ regeneration and develop innovative therapeutics for organ failure. Utilizing stem and progenitor cells for organ replacement has been conducted for many years when performing hematopoietic stem cell transplantation. Since the first successful transplantation of umbilical cord blood to treat hematological malignancies, non-hematopoietic stem and progenitor cell populations have recently been identified within umbilical cord blood and other perinatal and fetal tissues. A cell population entitled mesenchymal stromal cells (MSCs) emerged as one of the most intensely studied as it subsumes a variety of capacities: MSCs can differentiate into various subtypes of the mesodermal lineage, they secrete a large array of trophic factors suitable of recruiting endogenous repair processes and they are immunomodulatory.Focusing on perinatal tissues to isolate MSCs, we will discuss some of the challenges associated with these cell types concentrating on concepts of isolation and expansion, the comparison with cells derived from other tissue sources, regarding phenotype and differentiation capacity and finally their therapeutic potential. 展开更多
关键词 Mesenchymal stromal CELLS UMBILICAL CORD CORD blood Regenerative medicine Cell therapy Stem CELLS AMNION CHORION PERINATAL discarded tissue Fetal membranes
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Therapeutic Effects of Essential Oil from Waste Leaves of <i>Psidium guajava</i>L. against Cosmetic Embarrassment Using Phylogenetic Approach 被引量:1
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作者 Ahsan Kamran Rohit Mishra +3 位作者 Rita Gupta Awadhesh Kumar Ashok Bajaj Anupam Dikshit 《American Journal of Plant Sciences》 2012年第6期745-752,共8页
Medicinal plants are facing threats due to loss of habitat and overexploitation of knows species. Therefore the present work shows utilization of essential oil from discarded leaves of Psidium guajava Linn. against hu... Medicinal plants are facing threats due to loss of habitat and overexploitation of knows species. Therefore the present work shows utilization of essential oil from discarded leaves of Psidium guajava Linn. against human dermatophytic fungi Trichophyton rubrum, T. mentagrophytes, Trichophyton violaceum, Trichophyton tonsurans, Epidermophyton floccosum, Microsporum gypseum and Microsporum canis. The oil was found to be fungicidal at 3.0 μl/ml and it tolerated heavy inoculum of pathogens at fungicidal concentrations. The fungicidal activity of the oil was thermostable, up to 70°C and shelf life was found to be six months, which was maximum the time taken into consideration. The oil having cineole, caryophyllane, copaene, azulene and eucalyptol as main constituents, exhibited broad fungicidal activity. The oil did not show any adverse effect on mammalian skin upto 5% concentration. Phylogeny of the dermatophytes with respect to toxicity of the oil has also been discussed using molecular data. The cost effective formulation from waste leaves can be exploited after undergoing double blind successful multicentral topical testing. 展开更多
关键词 Essential Oil DERMATOPHYTES Phylogeny discarded LEAVES PSIDIUM guajava L. TRICHOPHYTON rubrum T. mentagrophyte
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Narrow-band imaging observation of colorectal lesions using NICE classification to avoid discarding significant lesions 被引量:5
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作者 Santa Hattori Mineo Iwatate +9 位作者 Wataru Sano Noriaki Hasuike Hidekazu Kosaka Taro Ikumoto Masahito Kotaka Akihiro Ichiyanagi Chikara Ebisutani Yasuko Hisano Takahiro Fujimori Yasushi Sano 《World Journal of Gastrointestinal Endoscopy》 CAS 2014年第12期600-605,共6页
AIM: To assess the risk of failing to detect diminutive and small colorectal cancers with the "resect and discard" policy.METHODS: Patients who received colonoscopy and polypectomy were recruited in the retr... AIM: To assess the risk of failing to detect diminutive and small colorectal cancers with the "resect and discard" policy.METHODS: Patients who received colonoscopy and polypectomy were recruited in the retrospective study. Probable histology of the polyps was predicted by six colonoscopists by the use of NICE classification. The incidence of diminutive and small colorectal cancersand their endoscopic features were assessed. RESULTS: In total, we found 681 cases of diminutive(1-5 mm) lesions in 402 patients and 197 cases of small(6-9 mm) lesions in 151 patients. Based on pathology of the diminutive and small polyps, 105 and 18 were non-neoplastic polyps, 557 and 154 were low-grade adenomas, 18 and 24 were high-grade adenomas or intramucosal/submucosal(SM) scanty invasive carcinomas, 1 and 1 were SM deeply invasive carcinoma, respectively. The endoscopic features of invasive cancer were classified as NICE type 3 endoscopically.CONCLUSION: The risk of failing to detect diminutive and small colorectal invasive cancer with the "resect and discard" strategy might be avoided through the use of narrow-band imaging observation with the NICE classification scheme and magnifying endoscopy. 展开更多
关键词 Image-enhanced endoscopy Narrowband imaging Resect and DISCARD NICE CLASSIFICATION Magnifying ENDOSCOPE COLONOSCOPY SUBMUCOSAL deeply
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Experimental evaluation of activated carbon derived from South Africa discard coal for natural gas storage 被引量:2
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作者 Jibril Abdulsalam Jean Mulopo +2 位作者 Bilainu Oboirien Samson Bada Rosemary Falcon 《International Journal of Coal Science & Technology》 EI 2019年第3期459-477,共19页
Lacking in literature is the use of discard coal to produce activated carbon and in its subsequent use in the storage of natural gas. In this study, the characterization and gas storage evaluation of a largely porous ... Lacking in literature is the use of discard coal to produce activated carbon and in its subsequent use in the storage of natural gas. In this study, the characterization and gas storage evaluation of a largely porous activated carbon with large surface area synthesized from discard coal were investigated. Discard coals are waste material generated from coal beneficiation process. In developing the activated carbon, chemical activation route with the use of KOH reagent was applied. The effects of KOH/discard coal weight ratio (1:1, 2.5:1, 4:1), temperature (400-800 ℃) and particle size (0.15-0.25 mm, 0.25-0.5 mm, 0.5-1 mm) on the adsorptive properties of the activated carbon were methodically evaluated and optimized using response surface methodology. The synthesized activated carbon was characterized using BET, SEM/EDS, and XRD. The results showed that for each activation process, the surface area and pore volume of the resulting activated carbon increased with increased temperature and KOH/discard coal weight ratio. The maximum surface area of 1826.41 m2/g, pore volume of 1.252 cm^3/g and pore size of 2.77 nm were obtained at carbonization temperature of 800 ℃ and KOH/discard coal weight ratio of 4:1. Methane and nitrogen adsorption data at high pressure were fitted to Toth isotherm model with a predictive accuracy of about 99%. Adsorption parameters using the Toth model provides useful information in the design of adsorbed natural gas storage system. According to the requirements of adsorbent desired for natural gas storage, it could be stated that the synthesized activated carbon could well be applied for natural gas storage. 展开更多
关键词 DISCARD COAL ACTIVATED carbon Surface area METHANE ADSORPTION
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Bacterial degradation of coal discard and geologically weathered coal 被引量:2
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作者 Jacob Taiwo Olawale Oghenekume Gerald Edeki Ashton Keith Cowan 《International Journal of Coal Science & Technology》 EI 2020年第2期405-416,共12页
The biodegradation of coal discard is being intensively studied in South Africa in an effort to develop passive methods for the successful revegetation and rehabilitation of waste dumps, to mitigate pollution, and fac... The biodegradation of coal discard is being intensively studied in South Africa in an effort to develop passive methods for the successful revegetation and rehabilitation of waste dumps, to mitigate pollution, and facilitate mine closure. Bacteria were isolated from slurries of coal tailings and diesel-contaminated soil, screened for coal biodegradation competence, characterized, and the colonization and degradation of coal discard and geologically weathered coal investigated using individual isolates and consortia. Ten novel coal-degrading bacterial strains were isolated and characterized, the gene sequences deposited with GenBank, and the (wild-type) strains deposited at Microbial Culture Collection, India. The results from the present work show that bituminous coal discard and geologically weathered coal is used by these isolates as carbon and energy source. Isolated strains and consortia colonized and degraded both coal substrates. Growth rate of the isolates is faster and stationery phase achieved sooner in minimal medium containing geologically weathered coal. This observation suggests that the oxygen-rich weathered coal is a more friable substrate and thus readily colonised and biodegraded. A reduction in mass of substrate is demonstrated for both individual isolates and consortia. The changes in pH and associated media colouration occurred concomitant with formation of humic acid-like (HS) and fulvic acid-like substances (FS) which is confirmed following analysis of these products by FT-IR spectroscopy. It is concluded that preferential metabolism of alkanes from the coal substrates provided the carbon and energy for bacterial growth and transformation of the substrates to HS and FS. 展开更多
关键词 BACTERIA BIODEGRADATION Coal discard Humic acid Fulvic acid FT-IR Geologically weathered coal
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Mathematical modeling of induction heating of discard substitution block for billet hot extrusion process 被引量:1
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作者 ZHU Hongda LEI Zuosheng +3 位作者 GUO Jiahong ZHOU Yueming JIN Xiaoli GAO Qi 《Baosteel Technical Research》 CAS 2016年第1期28-32,共5页
A magnetic and temperature field-coupled mathematical model is proposed to calculate the induction heating process of a discard substitution block for billet hot extrusion process. The mathematical model is validated ... A magnetic and temperature field-coupled mathematical model is proposed to calculate the induction heating process of a discard substitution block for billet hot extrusion process. The mathematical model is validated by comparing simulation results with temperature measurements recorded during physical modeling. Based on systematical analysis of calculation results, a quantitative sawtooth induction power curve was proposed to realize the aim of achieving the best distributed temperature field in the block within the shortest induction time. 展开更多
关键词 induction heating discard substitution hot extrusion mathematical modeling
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The use of demersal trawling discards as a food source for two scavenging seabird species:a case study of an eastern Mediterranean oligotrophic marine ecosystem
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作者 Georgios Karris Vlasis Ketsilis-Rinis +4 位作者 Anastasia Kalogeropoulou Stavros Xirouchakis Athanasios Machias Irida Maina Stefanos Kavadas 《Avian Research》 CSCD 2018年第3期239-252,共14页
Background: The banning of fisheries discards by imposing an obligation to land unwanted catch constitutes a key point of the Common Fishery Policy reform proposed by the European Commission. The effect of such a ban ... Background: The banning of fisheries discards by imposing an obligation to land unwanted catch constitutes a key point of the Common Fishery Policy reform proposed by the European Commission. The effect of such a ban on discards on top marine predators such as seabirds is largely unknown, especially in oligotrophic systems of the Medi?terranean. The current study investigates the presence of scavenging seabirds around fishing trawlers as well as the exploitation of discards produced by bottom trawlers in the eastern Ionian Sea.Methods: On?board observations were randomly conducted in May and December 2014, in order to record the presence and use of fishery discards by two common seabird species, namely, Scopoli's Shearwater(Calonectris diomedea) and the Yellow?legged Gull(Larus michahellis).Results: A total of 3400 seabirds were counted during May of which 2190 individuals were Scopoli's Shearwaters and 1210 were Yellow?legged Gulls. The latter species was the only scavenger observed during winter and in total, 768 individuals were counted. Differences in species abundance in the study area are related to breeding phenology and migratory movements. The number of seabirds attending bottom trawler operations during morning and afternoon hours showed no significant differences for both seabird species. Both scavenging seabirds extensively exploited fishery discards, which were mainly demersal fish, and consumed 70–80% of the total fishery discards biomass; how?ever, they appeared to avoid poisonous species and/or large?sized fish. Yellow?legged Gulls displayed kleptoparasitic behaviour on Scopoli's Shearwater during feeding experiments. The number of such incidents depended on the number of gulls around the fishing vessel, with more than 90% success rates.Conclusions: Considering the average annual biomass of discards estimations and the consumption rate found in this work, 106.1–117.9 t may be offered as a food subsidy to scavenging seabirds in the study area and should support a substantial part of local populations. Our results constitute baseline information on the annual amount of fishery discards and their exploitation rate by seabirds in the Ionian Sea, and suggest further work for a complete understand?ing of the potential impacts of the discards reform bill on seabirds. 展开更多
关键词 DISCARDS Fisheries Scopoli's Shearwater Yellow-legged Gull
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Corollary of Marine Eco-system Sustainability by Addressing the Issues of Bycatches
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作者 Pramod Kumar Pandey Biswajit Lahiri Amitava Ghosh 《Journal of Fisheries Science》 2020年第1期1-4,共4页
The issue of bycatch in the fisheries sector has been a major concern for the marine biologists over few decades in terms of conservation of marine eco-system and sustainability of the fisheries sector and marine biod... The issue of bycatch in the fisheries sector has been a major concern for the marine biologists over few decades in terms of conservation of marine eco-system and sustainability of the fisheries sector and marine biodiversity.As far as the concept of Bycatch is concerned,these are the unwanted species having less commercial importance,which in most of the cases disposed into the seas onboard or are caught during fishing.The article discusses the social,economic,cultural,and environmental impacts in addressing the issue of bycatch.The concern regarding bycatch is relatively new in the horizon in Indian perspective though it is often considered a major issue faced by developed nations since long.The problem of bycatch poses a serious threat to livelihoods and food security as it acts as a precursor to depletion of the food sources for local consumption with adverse social,economic,cultural,and environmental impacts.The adverse effects of by-catch can be mitigated through commercialisation of bycatch and making profits from the sale of bycatch,opening up of new markets for bycatch species or products,uses of bycatch as fishmeal and application of bycatch reduction devices(BRDs).Reorientation of the present monitoring system to collect fisheries data,strengthening technical know-how,bringing effective policy intervention,efficient co-management,and sincere and honest efforts in reducing bycatch and discards may provide a considerable impact towards sustainability of marine eco-system. 展开更多
关键词 Marine eco-system Bycatch and discards SUSTAINABILITY Marine fisheries
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C-DRX配置对Volte语音质量的影响分析
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作者 梁金山 赵明峰 +1 位作者 张皓彦 楚扬 《信息通信》 2016年第11期210-211,共2页
主要分析C-DRX周期对Volte语音质量的影响,并对典型的C-DRX配置进行了测试对比,以寻求一种较优的C-DRX参数配置方案,为Volte参数配置提供建议。
关键词 C-DRX DISCARD TIMER MOS值
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Study on the catch,bycatch and discard of Chinese pelagic longline fisheries in the Atlantic Ocean
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作者 Boyi Pan Jiangfeng Zhu +3 位作者 Qinqin Lin Zhe Geng Feng Wu Yuying Zhang 《Aquaculture and Fisheries》 CSCD 2024年第2期280-286,共7页
Catch,bycatch and discard information is important for the assessment and management of fisheries.Using Chinese pelagic tuna longline observer data from 2010 to 2018,we studied the catch composition in the Chinese pel... Catch,bycatch and discard information is important for the assessment and management of fisheries.Using Chinese pelagic tuna longline observer data from 2010 to 2018,we studied the catch composition in the Chinese pelagic tuna longline fisheries in Atlantic targeting bigeye tuna(Thunnus obesus)and bluefin tuna(Thunnus thynnus),and analyzed the survival status and discard rates of common bycatch species.A total of 55 species,including tunas,billfishes,sharks,sea turtles,cetaceans,seabirds,and other pelagic species,were observed.The results indicated that the catch composition of the Chinese pelagic tuna longline fishery targeting bigeye tuna was significantly different from that targeting bluefin tuna.The annual discard rates of common species decreased over this period.Discard rate by length and discard mortality for common species were varied among species.This is the first study to estimate catch,bycatch,and discard using Chinese pelagic tuna longline observer data in the Atlantic Ocean,which is important for the management of Chinese tuna longline fisheries in Atlantic Ocean. 展开更多
关键词 Longline fishery Catch composition DISCARD Size distribution ATLANTIC
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Modified Multi-Key Fully Homomorphic Encryption Based on NTRU Cryptosystem without Key-Switching 被引量:7
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作者 Xiaoliang Che Tanping Zhou +3 位作者 Ningbo Li Haonan Zhou Zhenhua Chen Xiaoyuan Yang 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2020年第5期564-578,共15页
The Multi-Key Fully Homomorphic Encryption (MKFHE) based on the NTRU cryptosystem is an important alternative to the post-quantum cryptography due to its simple scheme form,high efficiency,and fewer ciphertexts and ke... The Multi-Key Fully Homomorphic Encryption (MKFHE) based on the NTRU cryptosystem is an important alternative to the post-quantum cryptography due to its simple scheme form,high efficiency,and fewer ciphertexts and keys.In 2012,Lopez-Alt et al.proposed the first NTRU-type MKFHE scheme,the LTV12 scheme,using the key-switching and modulus-reduction techniques,whose security relies on two assumptions:the Ring Learning With Error (RLWE) assumption and the Decisional Small Polynomial Ratio (DSPR) assumption.However,the LTV12and subsequent NTRU-type schemes are restricted to the family of power-of-2 cyclotomic rings,which may affect the security in the case of subfield attacks.Moreover,the key-switching technique of the LTV12 scheme requires a circular application of evaluation keys,which causes rapid growth of the error and thus affects the circuit depth.In this paper,an NTRU-type MKFHE scheme over prime cyclotomic rings without key-switching is proposed,which has the potential to resist the subfield attack and decrease the error exponentially during the homomorphic evaluating process.First,based on the RLWE and DSPR assumptions over the prime cyclotomic rings,a detailed analysis of the factors affecting the error during the homomorphic evaluations in the LTV12 scheme is provided.Next,a Low Bit Discarded&Dimension Expansion of Ciphertexts (LBD&DEC) technique is proposed,and the inherent homomorphic multiplication decryption structure of the NTRU is proposed,which can eliminate the key-switching operation in the LTV12 scheme.Finally,a leveled NTRU-type MKFHE scheme is developed using the LBD&DEC and modulus-reduction techniques.The analysis shows that the proposed scheme compared to the LTV12 scheme can decrease the magnitude of the error exponentially and minimize the dimension of ciphertexts. 展开更多
关键词 NTRU-type Multi-Key Fully Homomorphic Encryption(MKFHE) prime cyclotomic rings Low Bit discarded(LBD) homomorphic multiplication decryption structure
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Effects of twine material on the marine debris and relative ghost fishing of portunid hoop (tangle) nets
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作者 Matt K.Broadhurst Russell B.Millar 《Aquaculture and Fisheries》 2020年第2期99-104,共6页
Portunids are important to recreational fisheries in Australia and typically are harvested by baited gears.Most of these baited gears are considered environmentally benign,although small conical hoop(tangle)nets fishe... Portunids are important to recreational fisheries in Australia and typically are harvested by baited gears.Most of these baited gears are considered environmentally benign,although small conical hoop(tangle)nets fished in southeastern Australia sometimes are damaged and lose twine,which becomes marine debris.Substituting conventional multifilament polyamide(PA)twine with alternative multi-monofilament and monofilament PA twines in hoop nets can dramatically reduce marine debris,but there remain unanswered questions concerning the relative fishing power of alternative twines among derelict hoop nets.This study addresses the shortfall in data by comparing the efficiencies and damage to replicate hoop nets made from the three twines and left to fish for short(one and two days),medium(three to five days)and long(ten and fourteen days)soaks.Irrespective of twine material or soak time,all hoop nets entangled the same numbers of giant mud crabs,Scylla serrata implying catch saturation within two days.Only four other animals were caught(all yellowfin bream,Acanthopagrus australis)and all died.At least some replicates of all hoop nets were damaged and lost twine,but this was greatest among the multifilament(up to a maximum of 9.3m hoop-net deployment−1),followed by the multi-monofilament(up to 7.4m hoop-net deployment−1)and monofilament hoop nets(1.4m hoop-net deployment−1).Replacing the existing multifilament twine in hoop nets with monofilament when targeting S.serrata would maintain catches and minimise marine debris during conventional soaks,without increasing ghost fishing over the short term. 展开更多
关键词 BYCATCH DECAPODS Discard mortality Unaccounted fishing mortality
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