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Development,Characterization and Application of a Three-Layer Intelligent pH-Sensing Indicator Based on Bromocresol Green(BCG)for Monitoring Fish Freshness
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作者 WEN Haiying OU Changrong +3 位作者 TANG Haiqing SANG Shangyuan DU Yingqi CHEN Jingyi 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第2期565-575,共11页
As a novel food quality monitoring technology,intelligent freshness indicator has received wide attention in recent years.However,its poor safety and stability are the main problems hindering its practical application... As a novel food quality monitoring technology,intelligent freshness indicator has received wide attention in recent years.However,its poor safety and stability are the main problems hindering its practical application.Hence a new pH-sensing indicator based on bromocresol green(BCG)was developed in this study for nondestructive and real-time monitoring the freshness of marine fishes.The indicator was designed with a three-layer structure,using the polytetrafluoroethylene(PTFE)membrane with high hydrophobicity and air permeability as the inner layer to isolate the moisture in the package,BCG-coated filter paper as the colorchanging layer to indicate the freshness of fish,and a transparent unidirectional permeable(TUP)membrane with moisture resistance as the out layer to isolate the moisture in the environment.This contributed to weaken the influence of humidity and prevent dye migration,so as to improve the accuracy and safety of the indicator.Therefore,a highly sensitive and distinguished color variation response to trimethylamine(TMA)standard solution with different concentrations was observed on the indicator.Additionally,the indicator showed a high color stability at different storage temperatures up to 14 days with total color differences(ΔE)less than 5.0.The indicator presented visible color variations from yellow to green then eventually to blue when applied to monitor the freshness of sea bass and salmon stored at 4℃,implying that fish was spoiled.Meanwhile,indicatorsΔE value was significantly positively correlated with total volatile basic nitrogen(TVB-N)and total viable count(TVC)in sea bass and salmon samples.Thus,the pH-sensing indicator can be applied as a cost-effective and promising intelligent indicator for monitoring fish freshness. 展开更多
关键词 fish freshness spoilage pH-sensing indicator color change bromocresol green(BCG) intelligent packaging
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Information Freshness-Oriented Trajectory Planning and Resource Allocation for UAV-Assisted Vehicular Networks
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作者 Hao Gai Haixia Zhang +1 位作者 Shuaishuai Guo Dongfeng Yuan 《China Communications》 SCIE CSCD 2023年第5期244-262,共19页
In this paper,multi-UAV trajectory planning and resource allocation are jointly investigated to improve the information freshness for vehicular networks,where the vehicles collect time-critical traffic information by ... In this paper,multi-UAV trajectory planning and resource allocation are jointly investigated to improve the information freshness for vehicular networks,where the vehicles collect time-critical traffic information by on-board sensors and upload to the UAVs through their allocated spectrum resource.We adopt the expected sum age of information(ESAoI)to measure the network-wide information freshness.ESAoI is jointly affected by both the UAVs trajectory and the resource allocation,which are coupled with each other and make the analysis of ESAoI challenging.To tackle this challenge,we introduce a joint trajectory planning and resource allocation procedure,where the UAVs firstly fly to their destinations and then hover to allocate resource blocks(RBs)during a time-slot.Based on this procedure,we formulate a trajectory planning and resource allocation problem for ESAoI minimization.To solve the mixed integer nonlinear programming(MINLP)problem with hybrid decision variables,we propose a TD3 trajectory planning and Round-robin resource allocation(TTPRRA).Specifically,we exploit the exploration and learning ability of the twin delayed deep deterministic policy gradient algorithm(TD3)for UAVs trajectory planning,and utilize Round Robin rule for the optimal resource allocation.With TTP-RRA,the UAVs obtain their flight velocities by sensing the locations and the age of information(AoI)of the vehicles,then allocate the RBs to the vehicles in a descending order of AoI until the remaining RBs are not sufficient to support another successful uploading.Simulation results demonstrate that TTP-RRA outperforms the baseline approaches in terms of ESAoI and average AoI(AAoI). 展开更多
关键词 information freshness for vehicular networks multi-UAV trajectory planning resource allocation deep reinforcement learning
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Information freshness optimization of multiple status update streams in Internet of things:Generation rate control and service rate reservation
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作者 Tianci Zhang Junjie Zhou +3 位作者 Zhengchuan Chen Zhong Tian Wanli Wen Yunjian Jia 《Digital Communications and Networks》 SCIE CSCD 2023年第4期971-980,共10页
The Internet of things(IoT)has become a key infrastructure providing up-to-date and fresh information for policy analysis and decision-making of upper-layer applications.However,there are limited sensing and communica... The Internet of things(IoT)has become a key infrastructure providing up-to-date and fresh information for policy analysis and decision-making of upper-layer applications.However,there are limited sensing and communication resources in IoT devices,which significantly affects the timeliness and freshness of the updated status.This work proposes two schemes,namely,the generation rate control and service rate reservation schemes,to improve the overall information freshness of multiple status update streams at the receiver.Specifically,using the recently proposed Age of Information(AoI)as the metric for evaluating information freshness,we characterized the overall information freshness,i.e.,the overall average AoI at the receiver for both schemes,by considering the urgency difference of status update and streams.Both schemes for status updates and streams,respectively,were formulated as two optimization problems.We proved that both problems are convex and the optimal generation and service rates for different streams are found by the standard convex optimization algorithm.Moreover,we proposed both approximate optimal generation and approximate optimal service rate for fast deployment in heavy and light load cases.Numerical results verify the theoretical findings and accuracy of the proposed approximate solutions,guiding the design and deployment of IoT. 展开更多
关键词 Internet of things Information freshness Age of information Multi-source M/M/1 queuing model
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Abomasal infusion of branched-chain amino acids or branched-chain keto-acids alter lactation performance and liver triglycerides in fresh cows
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作者 Kristen Gallagher Isabelle Bernstein +7 位作者 Cynthia Collings David Main Ghayyoor Ahmad Sarah Naughton Jayasimha Daddam Vengai Mavangira Mike Vandehaar Zheng Zhou 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1145-1157,共13页
Background Dairy cows are at high risk of fatty liver disease in early lactation,but current preventative measures are not always effective.Cows with fatty liver have lower circulating branched-chain amino acid(BCAA)c... Background Dairy cows are at high risk of fatty liver disease in early lactation,but current preventative measures are not always effective.Cows with fatty liver have lower circulating branched-chain amino acid(BCAA)concentra-tions whereas cows with high circulating BCAA levels have low liver triglyceride(TG).Our objective was to determine the impact of BCAA and their corresponding ketoacids(branched-chain ketoacids,BCKA)on production performance and liver TG accumulation in Holstein cows in the first 3 weeks postpartum.Methods Thirty-six multiparous Holstein cows were used in a randomized block design experiment.Cows were abomasally infused for the first 21 d postpartum with solutions of 1)saline(CON,n=12);2)BCA(67 g valine,50 g leu-cine,and 34 g isoleucine,n=12);and 3)BCK(77 g 2-ketovaline calcium salt,57 g 2-ketoleucine calcium salt,and 39 g 2-ketoisoleucine calcium salt,n=12).All cows received the same diet.Treatment effects were determined using PROC GLIMMIX in SAS.Results No differences were detected for body weight,body condition score,or dry matter intake averaged over the first 21 d postpartum.Cows receiving BCK had significantly lower liver TG concentrations compared to CON(6.60%vs.4.77%,standard error of the mean(SEM)0.49)during the first 3 weeks of lactation.Infusion of BCA increased milk yield(39.5 vs.35.3 kg/d,SEM 1.8),milk fat yield(2.10 vs.1.69 kg/d,SEM 0.08),and lactose yield(2.11 vs.1.67 kg/d,SEM 0.07)compared with CON.Compared to CON,cows receiving BCA had lower plasma glucose(55.0 vs.59.2 mg/dL,SEM 0.86)but higherβ-hydroxybutyrate(9.17 vs.6.00 mg/dL,SEM 0.80).Conclusions Overall,BCAA supplementation in this study improved milk production,whereas BCKA supplementa-tion reduced TG accumulation in the liver of fresh cows. 展开更多
关键词 Branched-chain amino acids Branched-chain ketoacids Fatty liver Fresh cow
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Effects of Functional Organic Materials on Fresh Weight,Quality,Single-melon Weight and SPAD Value of Watermelon
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作者 Kun CHEN Yuefeng ZHAO +5 位作者 Xiaoxue REN Mingda YANG Mingjun ZHAO Yumei WANG Xinhua HUANG Hao LIU 《Agricultural Biotechnology》 2024年第4期54-56,共3页
[Objectives]This study was conducted to explore a functional organic material formula suitable for watermelon cultivation with high quality,high yield and high efficiency.[Methods]Four treatments were set in the exper... [Objectives]This study was conducted to explore a functional organic material formula suitable for watermelon cultivation with high quality,high yield and high efficiency.[Methods]Four treatments were set in the experiment,namely four functional organic materials,garlic straw treatment(T_(1)),onion straw treatment(T_(2)),garlic straw+sheep manure treatment(T_(3))and onion straw+chicken manure treatment(T_(4)),to investigate the effects of different functional organic materials on fresh weight,quality,single-melon weight and SPAD value of watermelon.[Results]The effects of different functional organic materials on fresh weight,quality,single-melon weight and SPAD value of watermelon were quite different.The fresh weight,quality,single-melon weight and SPAD value of watermelon were higher in treatment T_(3)applying garlic straw and sheep manure and treatment T_(4)applying onion straw and chicken manure than in treatment T_(1)applying garlic straw and treatment T_(2)applying onion straw.Specifically,the fresh weight of whole plant was the highest in treatment T_(3),followed by treatment T_(4),and the values of the two treatments increased by 12.83%and 5.94%respectively compared with treatment T_(1);the weight of single melon was the highest in treatment T_(3),followed by treatment T_(4),and the values of the two treatments increased by 42.45%and 31.77%respectively compared with treatment T_(2);and the SPAD values of treatments T_(3)and T_(4)were significantly higher than those of treatments T_(1)and T_(2),and the value of treatment T_(3)was the largest.[Conclusions]This study provides theoretical support for the popularization and application of fertilization techniques combining organic fertilizers and reduced chemical fertilizers for watermelon. 展开更多
关键词 WATERMELON Organic materials Fresh weight QUALITY Single-melon weight SPAD value
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Fresh Processing Technology in Polygonatum odoratum Production Area and Its Comparison with Traditional Processing
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作者 Miao YANG Chufan PENG +4 位作者 Haixia LU Rufeng LIANG Hui TANG Zhongmei QIN Shengjiu GU 《Medicinal Plant》 2024年第1期38-40,44,共4页
[Objectives]To compare the effects of traditional processing and fresh processing on the quality of Polygonatum odoratum decoction piece.[Methods]The effects of fresh processing and traditional processing on the quali... [Objectives]To compare the effects of traditional processing and fresh processing on the quality of Polygonatum odoratum decoction piece.[Methods]The effects of fresh processing and traditional processing on the quality of P.odoratum decoction piece were compared and analyzed with appearance characteristics,total ash content,extract content,total polysaccharides content,and total flavonoids content as the evaluation indexes.[Results]Fresh processing method in different production areas has different effects on P.odoratum decoction piece.P.odoratum was dried in oven of 50℃.When moisture content was 41.44%-59.67%,it was cut.After complete drying at 50℃,the moisture content of dried P.odoratum was 8.94%-9.60%,and ethanol-soluble extract content was 77.29%-78.20%,and water-soluble extract was 77.7%-78.14%.At this time,the appearance characteristics of section of P.odoratum decoction piece were better than that of traditional processing,which was yellowish white.The total polysaccharide content was higher than that of traditional processing,and the content of total flavonoids was statistically significant different from that of traditional processing.[Conclusions]The quality of P.odoratum decoction piece by fresh processing is better than that of the traditional processing,and it is feasible to use fresh processing. 展开更多
关键词 Processing technique Plygonatum odoratum Fresh processing Total polysaccharide Total flavonoids
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A ratiometric fluorescent probe for hypoxanthine detection in aquatic products based on the enzyme mimics and fluorescence of cobalt-doped carbon nitride
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作者 Xin Wang Chengyi Hong +1 位作者 Zhengzhong Lin Zhiyong Huang 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期879-884,共6页
A ratiometric fluorescent probe for hypoxanthine(Hx)detection was established based on the mimic enzyme and fluorescence characteristics of cobalt-doped graphite-phase carbon nitride(Co doped g-C_(3)N_(4)).In addition... A ratiometric fluorescent probe for hypoxanthine(Hx)detection was established based on the mimic enzyme and fluorescence characteristics of cobalt-doped graphite-phase carbon nitride(Co doped g-C_(3)N_(4)).In addition to emitting strong fluorescence,the peroxidase activity of Co doped g-C_(3)N_(4)can catalyze the reaction of O-phenylenediamine and H_(2)O_(2)to produce diallyl phthalate which can emit yellow fluorescence at 570 nm.Through the decomposition of Hx by xanthine oxidase,Hx can be indirectly detected by the generating hydrogen peroxide based on the measurement of fluorescent ratio I(F_(570)/F_(370)).The linear range was 1.7-272.2 mg/kg(R^(2)=0.997),and the detection limit was 1.52 mg/kg(3σ/K,n=9).The established method was applied to Hx detection in bass,grass carp,and shrimp,and the data were verified by HPLC.The result shows that the established probe is sensitive,accurate,and reliable,and can be used for Hx detection in aquatic products. 展开更多
关键词 Co doped g-C_(3)N_(4) Ratiometric fluorescent probe HYPOXANTHINE freshness Aquatic products
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Physico-Chemical and Microbiological Study of Fresh Pineapple(Baronne de Guinée)Grown in the Sub-prefectures of:Maferinyah and Friguiagbé(Forécariah and Kindia Prefectures),Republic of Guinea
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作者 Sâa Gérard Tolno Haicha Cissé +3 位作者 Amadou Sylla Mamadou Madaniou Sow Adama Moussa Sakho Lounceny Traore 《Journal of Environmental Science and Engineering(A)》 CAS 2024年第6期211-217,共7页
Pineapple fruit in the Republic of Guinea is currently less competitive in the West African sub-region due to the nutritional quality of the product.Thus,it is normal to review certain parameters such as:sensory,physi... Pineapple fruit in the Republic of Guinea is currently less competitive in the West African sub-region due to the nutritional quality of the product.Thus,it is normal to review certain parameters such as:sensory,physico-chemical in order to improve this classification.To do this,instead of buying samples on the market,the aim is to analyze fresh samples harvested in the production fields and send them to the laboratory for analysis of certain physico-chemical and microbiological parameters.Analytical results showed that the Brix content in fields I and II at Maferinyah(Forécariah)was higher(14.35 and 16.5)than that found in fields I and II at Friguiagbé(Kindia)(14.2 and 12.4),The pH of fruit from both localities varies between 3.48 and 3.56,with the highest acidity value found in Field I at Friguiagbé(Kindia)2.16 and the lowest value in Field II at Maferinyah(Forécariah)0.46.Moisture contents for both localities ranged from 82.56 to 89.5,with the highest value found at Field I in Maferinyah(Forécariah)89.5.Dry extract and ash in both localities would be in the range 10.54 to 17.45;0.33 to 1.43 respectively.The highest values for dry extract and ash were found in Fields I and II Friguiagbé(Kindia)17.45 and 1.43.The samples analyzed contained certain trace elements such as magnesium,sodium,iron and phosphorus.Microbiological analyses showed the presence of Escherichia coli(E.coli),yeast-molds,Staphylococcus aureus and the absence of salmonella. 展开更多
关键词 Fresh pineapple cultivated physicochemical study microbiology
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Effect of Freshness Protection Package on Storage and Preservation of Chinese Cabbage 被引量:1
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作者 王希卓 孙洁 +2 位作者 张凯 杨琴 孙海亭 《Agricultural Science & Technology》 CAS 2016年第12期2742-2745,2808,共5页
The effect of freshness protection package on Chinese cabbage placed in the self-made shelf in ventilated storage was investigated, and the physiological-qual-ity indexes change were determined during the storage peri... The effect of freshness protection package on Chinese cabbage placed in the self-made shelf in ventilated storage was investigated, and the physiological-qual-ity indexes change were determined during the storage period. The results showed that the losses of weight and vitamin C were significantly reduced. The accumula-tion of crude fiber was effectively inhibited. But protein content was maintained at a low level and the rotting more serious of Chinese cabbage at the end of the stor-age packaged with the fresh keeping bags. 展开更多
关键词 freshness protection package Chinese cabbage PRESERVATION Ventilat-ed storage
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Effects of Salinity and Freezing on Freshness of Crucian
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作者 高桂生 史秋梅 +5 位作者 葛慕湘 陈娟 苏咏梅 董玉玲 韩红升 宋青春 《Agricultural Science & Technology》 CAS 2015年第12期2791-2794,2800,共5页
Salt tolerance and freeze preservation of crucian are always important concerns of people. There are rare reports on effect of different salinity on fresh- ness and quality. However, water salinity will directly affec... Salt tolerance and freeze preservation of crucian are always important concerns of people. There are rare reports on effect of different salinity on fresh- ness and quality. However, water salinity will directly affect osmotic pressure in fish, thereby affecting meat quality. In this study, the tolerance of crucian to different salinities (1‰, 2‰, 5‰, 8‰, 10‰ and 15‰) was investigated. In addition, the ef- fect of different salinity on freezing freshness and quality of crucian was studied. The results showed that the tolerance threshold of crucian to salinity was about 8‰, and the freezing quality of crucian in water with salinity of ‰ was significantly better than that in fresh water. 展开更多
关键词 Crucian SALINITY Salt tolerance freshness
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A Cooperative Schema between Web Sever and Search Engine for Improving Freshness of Web Repository 被引量:1
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作者 WEN Kun-mei LU Zheng-ding LI Yu-hua SUN Xiao-lin 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第1期11-14,共4页
Because the web is huge and web pages are updated frequently, the index maintained by a search engine has to refresh web pages periodically. This is extremely resource consuming because the search engine needs to craw... Because the web is huge and web pages are updated frequently, the index maintained by a search engine has to refresh web pages periodically. This is extremely resource consuming because the search engine needs to crawl the web and download web pages to refresh its index, Based on present technologies of web refreshing, we present a cooperative schema between web server and search engine for maintaining freshness of web repository. The web server provides metadata defined through XML standard to describe web sites. Before updating the web page the crawler visits the meta-data files. If the meta-data indicates that the page is not modified, then the crawler will not update it. So this schema can save bandwidth resource. A primitive model based on the schema is implemented. The cost and efficiency of the schema are analyzed. 展开更多
关键词 search engine freshness cooperative schema
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Fruits and Vegetables Freshness Categorization Using Deep Learning 被引量:2
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作者 Labiba Gillani Fahad Syed Fahad Tahir +3 位作者 Usama Rasheed Hafsa Saqib Mehdi Hassan Hani Alquhayz 《Computers, Materials & Continua》 SCIE EI 2022年第6期5083-5098,共16页
The nutritional value of perishable food items,such as fruits and vegetables,depends on their freshness levels.The existing approaches solve a binary class problem by classifying a known fruit\vegetable class into fre... The nutritional value of perishable food items,such as fruits and vegetables,depends on their freshness levels.The existing approaches solve a binary class problem by classifying a known fruit\vegetable class into fresh or rotten only.We propose an automated fruits and vegetables categorization approach that first recognizes the class of object in an image and then categorizes that fruit or vegetable into one of the three categories:purefresh,medium-fresh,and rotten.We gathered a dataset comprising of 60K images of 11 fruits and vegetables,each is further divided into three categories of freshness,using hand-held cameras.The recognition and categorization of fruits and vegetables are performed through two deep learning models:Visual Geometry Group(VGG-16)and You Only Look Once(YOLO),and their results are compared.VGG-16 classifies fruits and vegetables and categorizes their freshness,while YOLO also localizes them within the image.Furthermore,we have developed an android based application that takes the image of the fruit or vegetable as input and returns its class label and its freshness degree.A comprehensive experimental evaluation of proposed approach demonstrates that the proposed approach can achieve a high accuracy and F1score on gathered FruitVeg Freshness dataset.The dataset is publicly available for further evaluation by the research community. 展开更多
关键词 Fruits and vegetables classification degree of freshness deep learning object detection model VGG-16 YOLO-v5
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Changes of structure and functional properties of rice protein in the fresh edible rice during the seed development 被引量:5
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作者 Dan Li Mingjing Yao +3 位作者 Yang Yang Bing Wang Dongjie Zhang Na Zhang 《Food Science and Human Wellness》 SCIE CSCD 2023年第5期1850-1860,共11页
It has been reported that fresh edible rice has more bioactive compounds and its protein is easier to digest and has lower hypoallergenic than mature rice. In this paper, the changes in structure and functional proper... It has been reported that fresh edible rice has more bioactive compounds and its protein is easier to digest and has lower hypoallergenic than mature rice. In this paper, the changes in structure and functional properties of proteins at five different stages, including early milky stage(EMS), middle milky stage(MMS), late milky stage(LMS), waxy ripe stage(WS)and ripening stage(RS), during the seed development were investigated. It was found that with the seed developing, the molecular weight of fresh rice protein gradually become larger while the secondary structure changed from the highest content of disordered structure at MMS to the highest content of ordered structure at RS, which affect the surface hydrophobicity and then the functional properties of proteins, including foaming properties, emulsifying properties and oil holding capacity. Fresh rice protein at MMS has the strongest surface hydrophobicity while fresh edible rice protein at RS has the strongest oil holding capability. The results of our study can provide a theoretical basis for the application of fresh rice protein in the food industry and help to develop new fresh edible rice food. 展开更多
关键词 Fresh edible rice Rice protein Protein structure Functional properties
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Wi-freshness:基于CSI的猪肉新鲜度检测系统研究 被引量:3
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作者 牛超 杨卫东 +2 位作者 胡鹏明 高向上 沈二波 《物联网学报》 2023年第2期143-152,共10页
有效、快速地评价猪肉新鲜度对猪肉品质监测具有重要意义。然而,传统的感官评价方法过于主观,理化分析又耗时过长且具有破坏性。虽然射频信号被用于定位、材料识别、生命体征监测,但在肉类新鲜度检测方面并未受到重视。提出了一种实时... 有效、快速地评价猪肉新鲜度对猪肉品质监测具有重要意义。然而,传统的感官评价方法过于主观,理化分析又耗时过长且具有破坏性。虽然射频信号被用于定位、材料识别、生命体征监测,但在肉类新鲜度检测方面并未受到重视。提出了一种实时、无损、低成本的基于信道状态信息(CSI,channel state information)的猪肉新鲜度检测系统Wi-freshness。该系统基于泛在网络(商用Wi-Fi)部署和实施,是物联网在生鲜农产品领域一个新的应用。Wi-freshness包括CSI数据感知、数据预处理、检测建模和新鲜度检测4个模块。考虑Wi-freshness需要处理的数据特征值不多,以及对预测的实时性要求较高的特点,提出一种基于宽度学习系统(BLS,broad learning system)的检测模型。实验结果表明,Wi-freshness系统能达到93%以上的检测准确率。 展开更多
关键词 信道状态信息 WI-FI 猪肉新鲜度检测 宽度学习系统
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Impact of Progressive Pruning on Leaf Miner (Coelaenomenodera lameensis) Incidence and the Yield of Oil Palm (Elaeis guineensis) —A Case Study of Benso Oil Palm Plantation Plc, Adum Banso Estate, Ghana
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作者 Isaac Addo Emmanuel Ackah +5 位作者 Samuel Avaala Awonnea Kwasi Baah Ofori Victor Tetteh Zutah Geoffrey Smith Oduro Esther Fobi Donkor Kwadwo Gyasi Santo 《American Journal of Plant Sciences》 CAS 2023年第3期377-389,共13页
The oil palm leaf miner, Coelaenomenodera lameensis, is currently the most destructive pest of oil palm in Ghana and other African oil palm growing countries, causing significant losses in fresh fruit bunch yield. Pro... The oil palm leaf miner, Coelaenomenodera lameensis, is currently the most destructive pest of oil palm in Ghana and other African oil palm growing countries, causing significant losses in fresh fruit bunch yield. Progressive pruning is an oil palm pruning method in which pruning is done at the same time as fresh fruit bunch harvesting. This study evaluated the impact of progressive pruning on leaf miner population in oil palm and how these two factors (leaf miner and progressive pruning) affect the yield of oil palm at the Benso Oil Palm Plantation Public listed company (BOPP. Plc). Five distinct blocks in the plantation were selected for observations on fronds at various ranks (33, 25, or 17) based on the degree of defoliation by counting the number of pests on leaflets at different phases of insect development. Fronds from selected plots were sampled in a Completely Randomized Design (CRD). The size of plots used for the study ranged between 19 to 45 hectares. A minimum of 78 fronds were evenly cut from each block for pest count depending on the block size. Secondary data on annual yields of fresh fruit bunches before and after the introduction of progressive pruning were also obtained from BOPP. Plc records from 2011-2020. The results from the analyzed data on leaf miner index before and after the introduction of progressive pruning showed that progressive pruning has, to a high extent (64% to 36%), reduced leaf miner populations in the plantation. Paired t-test on fresh fruit bunch yield has also revealed a significant (p < 0.001) increase in annual fresh fruit bunch yield due to progressive pruning. A regression analysis, however, revealed a lower rate of yield loss (3.05 to 2.70 tonnes) to leaf miner infestation after the introduction of progressive pruning. The study recommends progressive pruning as a key cultural practice for improving crop yields in leaf miner prone plantations. 展开更多
关键词 Coelaenomenodera lameensis Elaeis spp Leaf Miner Oil Palm Progressive Pruning Fresh Fruit Bunch BOPP. Plc
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Distributionally Robust Newsvendor Model for Fresh Products under Cap-and-Offset Regulation
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作者 Xuan Zhao Jianteng Xu Hongling Lu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第8期1813-1833,共21页
The cap-and-offset regulation is a practical scheme to lessen carbon emissions.The retailer selling fresh products can adopt sustainable technologies to lessen greenhouse gas emissions.We aim to analyze the optimal jo... The cap-and-offset regulation is a practical scheme to lessen carbon emissions.The retailer selling fresh products can adopt sustainable technologies to lessen greenhouse gas emissions.We aim to analyze the optimal joint strategies on order quantity and sustainable technology investment when the retailer faces stochastic market demand and can only acquire the mean and variance of distribution information.We construct a distributionally robust optimization model and use the Karush-Kuhn-Tucker(KKT)conditions to solve the analytic formula of optimal solutions.By comparing the models with and without investing in sustainable technologies,we examine the effect of sustainable technologies on the operational management decisions of the retailer.Finally,some computational examples are applied to analyze the impact of critical factors on operational strategies,and some managerial insights are given based on the analysis results. 展开更多
关键词 Distributionally robust optimization KKT conditions cap-and-offset regulation fresh products
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Bio-Efficacy of Plant-Derived Pesticides against Fall Armyworm (Spodoptera frugiperda) and Their Interactive Effects on Maize Agronomic Performance under Field Conditions
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作者 Junias Sogra Lux Jimmy +1 位作者 Kenndy Kamik Alex Galus 《Agricultural Sciences》 2023年第11期1535-1546,共12页
Maize is widely cultivated in Papua New Guinea (PNG) and provides farmers with nutrition and income. However, the fall armyworm (FAW) (Spodoptera frugiperda) (J.E. Smith) (Lepidoptera: Noctuidae) invasion is a threat ... Maize is widely cultivated in Papua New Guinea (PNG) and provides farmers with nutrition and income. However, the fall armyworm (FAW) (Spodoptera frugiperda) (J.E. Smith) (Lepidoptera: Noctuidae) invasion is a threat to its production and supply. Hence, this field experiment was conducted to assess the bio-efficacy of plant-derived pesticides (PDPs) against FAW and their interactive effects on maize agronomic performance under field conditions. The treatments studied were turmeric rhizome extract (TRE), neem leaf ash solution (NLAS), neem bark extract (NBE), and untreated plots (control) and were replicated 5 times using the randomized complete block design. The data were subjected to analysis of variance and means were separated by Fisher’s protected least significant difference test. The result showed that the application of PDPs significantly reduced FAW infestation during the period of peak infestation. At 33 DAS, NBE significantly had the lowest number of FAW larvae (0.6) [F (4, 15) = 5.11, p = 0.02] and FAW attack intensity (29.8%) [F (4, 15) = 8.69, p F (4, 15) = 3.58, p = 0.04] and had the highest number of harvested ears (5.0) [F (4, 15) = 3.72, p = 0.04] and fresh ear weights (447 g) [F (4, 15) = 4.65, p = 0.02] compared to NLAS. The TRE and NLAS had performed poorly relative to the control. Hence, NBE can be used to control FAW infestation at a period of high attack intensity (33 DAS). Moreover, this study will provide basic information for future studies on biopesticidal plant extracts as a control of FAW infestation under field conditions in PNG. 展开更多
关键词 FAW Larvae Attack Intensity Plant Height Harvested Ear Ear Fresh Weight
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不同品种鲜食糯玉米采后贮藏品质及抗氧化酶活性的变化 被引量:5
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作者 范文广 陈少青 +3 位作者 周新原 郑鄢燕 左进华 王清 《食品工业科技》 CAS 北大核心 2024年第2期307-315,共9页
为探究不同品种鲜食糯玉米采后贮藏品质及抗氧化酶活性变化规律,选用京科糯2000、京科糯768以及农科糯336为材料,研究其在20℃常温贮藏条件下感官品质、硬度、失重率、色泽、V_(C)、可溶性固形物、糖类物质、丙二醛含量和抗氧化酶活性... 为探究不同品种鲜食糯玉米采后贮藏品质及抗氧化酶活性变化规律,选用京科糯2000、京科糯768以及农科糯336为材料,研究其在20℃常温贮藏条件下感官品质、硬度、失重率、色泽、V_(C)、可溶性固形物、糖类物质、丙二醛含量和抗氧化酶活性的变化规律。结果表明,随着贮藏天数的延长,不同品种鲜食糯玉米均出现不同程度地籽粒失水皱缩、风味散失、光泽和甜度下降等现象,京科糯768表面劣变最为严重,其次是农科糯336,京科糯2000籽粒表面劣变程度最轻。三个品种鲜食糯玉米的硬度、L*值、V_(C)、可溶性固形物、可溶性糖含量均下降,失重率、b*值、淀粉和丙二醛含量总体升高。农科糯336中V_(C)、可溶性固形物和可溶性糖含量下降幅度最小,且淀粉和丙二醛含量上升幅度最小,并且可溶性糖含量和过氧化物酶(Peroxidase,POD)活性显著高于京科糯2000与京科糯768(P<0.05),而抗坏血酸过氧化物酶(Ascorbate peroxidase,APX)活性显著高于京科糯768(P<0.05)。综上,农科糯336在贮藏期间具有更好的营养价值和贮藏品质,并且还具有较高的POD活性。京科糯2000在贮藏期间,果实内部葡萄糖、果糖以及L*值的下降幅度和b*值上升幅度均最小,感官品质较好。而京科糯768能更好地维持玉米籽粒硬度值。 展开更多
关键词 不同品种 鲜食糯玉米 贮藏品质 抗氧化酶
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Role of Fresh Cadaver Practice and Jesus Prayers on Daily Base in Innovations of a Difficult Neurosurgical Operation (Craniopagus Separation)
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作者 András Csókay István Hudák +6 位作者 István Valálik Attila Jósvai Bence Trencsényi Előd Égető Bertalan Tóth Bernadett Csókay Gergely Csókay 《Open Journal of Modern Neurosurgery》 2023年第4期189-201,共13页
Purpose: Challenging cases in neurosurgery require experience, which is gained by operating on a number of similarly difficult cases. However, even in large population centers, there are extremely rare cases, such as ... Purpose: Challenging cases in neurosurgery require experience, which is gained by operating on a number of similarly difficult cases. However, even in large population centers, there are extremely rare cases, such as craniopagus twins. In these instances, other case-specific solutions are required which were improved in the course of fresh cadaver practice on daily base. Methods: During a 20-month preparation period by fresh cadavers the surgical strategy was developed step by step, comprising five neurosurgical ideas, facilitated by deep Jesus prayers as a spiritual source. Possible causes of postoperative complications that occured on 33d postoperative day were also analyzed. Results: During surgery, these nuances proved to be useful, which is also reflected by the postoperative clinical results. One of the twins advanced to a GOS score of 5three months after the surgery. The other twin, despite nonsurgical septic complications, continued to progress well, but on postoperative day 33 for seemingly unknown reasons, she suffered a severe cerebral hemorrhage, which significantly delayed her rehabilitation. A thorough revision of the whole process much later revealed a pitfall that could have a role in this complication. Conclusions: The challenging neurosurgical separation of the craniopagus twins was carried out successfully with the help of five novel neurosurgical refinements, which were found during 300 fresh cadaver practices. Mistakes can serve as a lesson. We hope that the procedures developed and the knowledge gained can be applied in the future. 展开更多
关键词 CRANIOPAGUS Conjoined Twins Fresh Cadaver Practice
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3D bioprinting of complex biological structures with tunable elastic modulus and porosity using freeform reversible embedding of suspended hydrogels
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作者 Zhuang Chen Chuanzhen Huang +5 位作者 Hanlian Liu Xu Han Zhichao Wang Shuying Li Jun Huang Zhen Wang 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2023年第5期550-562,共13页
Three-dimensional(3D)bioprinting has been used widely for the construction of hard tissues such as bone and cartilage.However,constructing soft tissues with complex structures remains a challenge.In this study,complex... Three-dimensional(3D)bioprinting has been used widely for the construction of hard tissues such as bone and cartilage.However,constructing soft tissues with complex structures remains a challenge.In this study,complex structures characterized by both tunable elastic modulus and porosity were printed using freeform reversible embedding of suspended hydrogels(FRESHs)printing methods.A mixture of alginate and gelatin was used as the main functional component of the bioink.Rheological analysis showed that this bioink possesses shear thinning and shear recovery properties,supporting both cryogenic and FRESH printing methods.Potential printing capabilities and limitations of cryogenic and FRESH printing were then analyzed by printability tests.A series of complex structures were printed by FRESH printing methods which could not be realized using conventional approaches.Mechanical tests and scanning electron microscopy analysis showed that the printed structure is of excellent flexibility and could be applied in various conditions by adjusting its mechanical modulus and porosity.L929 fibroblast cells maintained cell viability in cell-laden-printed structures,and the addition of collagen further improved the hydrogels’biocompatibility.Overall,all results provided useful insight into the building of human soft tissue organ blocks. 展开更多
关键词 Bioink Freeform reversible embedding of suspended hydrogels(FRESHs)printing 3D extrusion cell-laden printing Tissue engineering Tunable elastic modulus and porosity
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