Preventing Hg Transference from Soil to Terrestrial Food Chain

Hg in acid soil could be activited by liming and become available to plant, if excessive or insufficient amount of lime was applied. The changes of Hg activity in acid soil with different rates of CaCO3 amendment Were studied by a pot experiment. To predict the adequate amount of lime application, a simple method using the pH (EDTA) as an indicator was suggested. The suitable range of lime application was the amount of lime addition when the pH of soil-EDTA system was.raised to 4.0-4.3.

Biotransfer of heavy metals along a soil-plant-insect-chicken food chain:Field study

The accumulation and transfer of Pb,Zn,Cu,and Cd along a soil-plant-insect-chicken food chain at contaminated sites were investigated.The study site nearing the Pb/Zn mine had been contaminated by heavy metals severely.Cadmium and Pb concentrations steadily declined with increasing trophic level（p 〈 0.01）,but concentrations of Zn and Cu slightly increased from plant to insect larva（p 〉 0.05）.The concentrations of heavy metals were the highest in chicken muscle,with lower values in liver and blood.The bioaccumulation of Pb was observed in chicken livers.The eliminations of Pb,Zn,Cu,and Cd via insect and chicken feces avoid metal bioaccumulation in insect and chicken body.These results suggest that the accumulation of heavy metals in specific animal organ of tissues could not be neglected,although transfer of metals to chicken from plant and insect was limited.

Transfer of Paralytic Shellfish Toxins via Marine Food Chains:A Simulated Experiment

Objective To study the transfer of paralytic shellfish toxins （PST） using four simulated marine food chains： dinoflagellate Alexandrium tamarense→Artemia Artemia salina→Mysid shrimp Neomysis awatschensis; A. tamarense→N. awatschensis; A. tamarense→A, salina→Perch Lateolabrax japonicus; and A. tamarense→L, japonicus. Methods The ingestion of A. tamarense, a producer of PST, by L. japonicus, N. awatschensis, and A. salina was first confirmed by microscopic observation of A. tamarense cells in the intestine samples of the three different organisms, and by the analysis of Chl.a levels in the samples. Toxin accumulation in L. japonicus and N. awatschensis directly from the feeding on A. tamarense or indirectly through the vector of A. salina was then studied, The toxicity of samples was measured using the AOAC mouse bioassay method, and the toxin content and profile of A. tamarense were analyzed by the HPLC method. Results Both A. salina and N. awatschensis could ingest A. tamarense cells. However, the ingestion capability of A. salina exceeded that of N. awatschensis. After the exposure to the culture of A. tamarense （2 000 cells·mL^-1） for 70 minutes, the content of Chl.a in A. salina and N. awatschensis reached 0.87 and 0.024 μg.mg^-1, respectively. Besides, A. tamarense cells existed in the intestines of L. japonicus, N. awatschensis and A. salina by microscopic observation. Therefore, the three organisms could ingest A. tamarense cells directly. A. salina could accumulate high content of PST, and the toxicity of A. salina in samples collected on days 1, 4, and 5 of the experiment was 2.18, 2.6, and 2.1 MU.g^-1, respectively. All extracts from the samples could lead to death of tested mice within 7 minutes, and the toxin content in anemia sample collected on the 1st day was estimated to be 1.65×10 ^5 μg STX equal/individual. Toxin accumulation in L japonicus and N. awatschensis directly from the feeding on A. tamarense or indirectly from the vector ofA. salina was also studied. The mice injected with extracts from L japonicus and N. awatschensis samples that accumulated PST either directly or indirectly showed PST intoxication symptoms, indicating that low levels of PST existed in these samples. Conclusion Paralytic shellfish toxins can be transferred to L. japonicus, N. awatschensis, and A. salina from A. tamarense directly or indirectly via the food chains.

Analysis of Information Sharing Mechanism in the Food Industry Green Supply Chain Management and Operation Process

In order to effectively address the issues of environmental pollution and food safety in food industry,the green supply chain management should be used in the food industry.However,information sharing is the basis of supply chain management.For this purpose,on the basis of describing the connotation of food industry green supply chain management,the paper introduces the contents and the effects of information sharing mode in detail.It focuses on the barriers of the implementation of information-sharing mechanisms in the food industry green supply chain management and operation process and analyzes the necessity of using information sharing mechanism among the members of the food industry green supply chain management mode by game theory,so as to strengthen the competitiveness of enterprises through supply chain management.

Safety reliability optimal allocation of food cold chain

This paper applied the safety reliability of food cold chain logistics to establish reliability allocation model for cold chain systems, designed optimization algorithms, and made a case analysis. By applying system reliability allocation principle, this article firstly built safety reliability allocation model of food cold chain logistics system without cost constraint based on the safety reliability model of food cold chain logistics system, and then it set up optimal decision- making model of food cold chain logistics system with cost constraint using the functional relationship between the time, temperature of cold chain logistics and logistics costs. Next, according to the characteristics of the model, a heuristic algorithm was proposed to allocate safety reliability of the system to each cold chain unit so as to achieve the goal of operatingcosts optimization subject to assurance ofoverall safety reliability of the cold chain system. Taking the safety impact factor of food cold chain unit as a weight, the article also deduced the equation of reallocation of safety reliability of food cold chain system. In the end, these models were used to optimize the allocation of safety reliability in an example of Sushi cold chain process. It provided a new thought and method to optimally plan the unit safety of food cold chain system as well as reduce the cost of food cold chain.

Poverty reduction through the development of inclusive food value chains

Propelled by urbanization,rising incomes,and changing diets,food markets have been expanding in Africa and South Asia,creating the vast potential for job and income opportunities along food supply chains and,hence,for poverty reduction.The novel coronavirus(COVID-19)that spread to a pandemic in early 2020 provokes enormous setbacks to this expansion.This,however,should provide lessons regarding the importance of resilient and inclusive food systems.Emergency responses to COVID-19 should consider interventions towards that end and leverage the opportunities provided by food markets growth as economies recover from the present economic recession.This paper assesses options of how this could be done by facilitating the better functioning and interconnectedness of the many small and medium-sized enterprises that are proliferating along the"hidden middle"of food value chains in storage,logistics,transportation,and wholesale and retail distribution.It also explores how policies can help smallholder farmers connect to this"hidden middle"in more gainful ways and help them climb out of poverty as well.

COPPER ACCUMULATION AND TRANSPORT IN A MARINE FOOD CHAIN COMPOSED OF PLATYMONAS SUBCORDIFORMIS, BRACHIONUS PLICATILIS AND PENAEUS MONODON

Accumulation, transport and toxicity of Cu in the food chain consisting of Platymonas subcordiformis,Brachionus plicatilis and Penaeus monodon were studied,Effects of Cu on the growth of organisms in the food chain were investigated and the inhibiting the concentration (EC50) of Cu was then determined according to the dynamics of the relative number of cells or total individuals of organisms, expressed in percentagn with reference to the controlled system under different culture conditions. On the basis of the variations in accumulation and percentages of accumulation of Cu in the biological phase, tbe reationship between the accumulation of Cu in organisms and its toxicity was analyzed and the main approach for determining the transport of Cu in the food chain was then discussed.

Optimal harvesting for an age-dependent n-dimensional food chain model

This paper is concerned with optimal harvesting policy for an age-dependent n-dimensional food chain model. The existence and uniqueness of non-negative solution of the system are proved using the fixed point theorem. By Mazur＇s theorem, the existence of optimal control strategy is demonstrated and optimality conditions derived by means of normal cone.

A dynamic food-chain model and program for predicting the consequences of nuclear accident

A dynamic food chain model and program, DYFOM 95, for predicting the radiological consequences of nuclear accident has been developed, which is not only suitable to the West food chain but also to Chinese food chain. The following processes, caused by accident release which will make an impact on radionuclide concentration in the edible parts of vegetable were considered: dry and wet deposition interception and initial retention, translocation, percolation, root uptake and tillage. Activity intake rate of animals, effects of processing and activity intake of human through ingestion pathway ware also considered in calculations. The effects of leaf area index LAI of vegetable were considered in dry deposition model. A method for calculating the contribution of rain with different period and different intensity to total wet deposition was established. The program contains 1 main code and 5 sub codes to calculate dry and wet deposition on surface of vegetable and soil, translocation of nuclides in vegetable, nuclide concentration in the edible parts of vegetable and in animal products and activity intake of human and so on.

Antibiotic susceptibility and molecular characterization of resistance genes among Escherichia coli and among Salmonella subsp. in chicken food chains

Objective: To investigate the occurrence of resistance genes among Escherichia coli(E. coli) and Salmonella subsp. isolated in chicken food chains in Phnom Penh, 2012–2013.Methods: Six hundred eighty two E. coli and 181 Salmonella Albany, Corvallis, and Kentucky strains were examined for susceptibilities to eight antimicrobials and following resistance genes were identified by PCR: blaTem, Str A, aad A, sul1, sul2, gyr A, Tet(A), and Tet(B).Results: E. coli presented high resistances to tetracycline, amoxicillin, and sulfamethoxazole(63.1%–76.1%). Salmonella Albany and Salmonella Kentucky traduced high resistance percentages to amoxicillin, tetracycline, sulfamethoxazole, and nalidixic acid(84.6%–100%). Among amoxicillin-resistant isolates, blaTemgenes were observed for 62% of E. coli isolates and 20% of 65 Salmonella Kentucky. The Str A gene was prevalent in 36% of 331 aminoglycoside-resistant E. coli and 90% of 40 aminoglycoside-resistant Salmonella Corvallis. The sul2 gene was predominant among sulfamethoxazole-resistant isolates, for 56% of 431 E. coli and 53% of 66 Salmonella Corvallis; the sul1 gene was observed in 54% of Salmonella Albany. The Tet(A) resistance gene was prevalent in E.coli(86%), Salmonella Corvallis(82%), Salmonella Kentucky(84%). High percentages of gyr A genes observed among nalidixic-acid resistant E. coli(91%), Salmonella Albany(92%), Salmonella Corvallis(75%) and Salmonella Kentucky(85%).Conclusions: Important occurrences of resistance gene were observed among E. coli and Salmonella in chicken food chains in Cambodia.

Dioxins in the Food Chain: Contamination Fingerprint Analysis in Breeding Hens, Hatching Eggs and Broilers

While routine monitoring poultry meat was obtained from breeding hens, dioxins contaminations were detected in Portugal. Levels of 430.9 pg PCDD/F-WHO-TEQ/g1 were found, which are higher than the official limits legally allowed for this matrix (1.75 pg PCDD/F-WHO-TEQ/g). To identify the magnitude of the contaminations, 60 samples were collected from poultry farms and different matrices, namely: feed, water, wood shavings from the litters, muscle of the breeding hens, hatching eggs collected in the positive farm and muscle collected from broilers farms supplied by the positive breeding farm. The comparison of the dioxins congeners profiles showed that there was a coincidence of peaks of higher relative concentrations in the wood shavings, with the peaks of the highest relative concentration in the hatching eggs, especially the relative concentrations of the congeners 1,2,3,4,6,7,8-HpCDD and OCDD, which may be explained by the role of VLDLy in the delivery of triglycerides to the oocyte, where they will be used as the energy source for the developing embryo. The comparison of the dioxins congeners profiles of the breeding hens muscle with the poultry muscle, showed a coincidence of peaks of higher relative concentrations in the congeners 1,2,3,7,8-PeCDD, 1,2,3,6,7,8-HxCDD, 1,2,3,4,6,7,8-HpCDD and OCDD which may indicate a dechlorination pathway “in vivo”. Results allowed concluding that those wood shavings, improperly used as poultry litters, were certainly the source of contamination of the food chain.

Impact of COVID-19 Epidemic on the International Food Supply Chain and Countermeasures of Shandong Province

The COVID-19 epidemic has exerted an impact on the global food supply chain,and also has contributed to the tendency of food hoarding and short supply;strong food demand has led to a rapid rise in international food prices,which has put enormous pressure on China's food import,and domestic food price showed a rise trend accordingly.In order to ensure sufficient and stable supply of China's food market,it is necessary to adhere to the food security strategy of"food self-sufficiency"for a long term.In the spring agricultural production,Shandong Province has taken effective measures to stabilize food production and achieved good results.It has not been greatly affected by the COVID-19 epidemic;however,under the continuous spread of foreign epidemics,we must adhere to the dual hard core operation of epidemic prevention and production,and explore the establishment of technical specifications for agricultural production under normal conditions for epidemic prevention and control to ensure the food security.

Strategic Agricultural Commodity Value Chains in Africa for Increased Food: The Regional Approach for Food Security

The challenge Africa faces the most is how to feed the 2.4 billion people in 2050. This will require a transformational agriculture. Africa doesn’t need subsistence agriculture, but rather agriculture linked to the market where market demand and the consuming habits are taken in consideration. Agriculture evolves in an environment where small holders are linked to markets (national and regional), where economies of complementarity and economies of scale are taken advantage of by producers and private sector. In short, Africa will need a paradigm shift to industrialise and commercialise its agriculture sector in order to increase food production, and income and to create jobs in and outside the sector. Africa needs agribusiness and agro-industries to domesticate the benefits of the sector, to create wealth in the sector and retain that wealth in the continent. Agricultural commodities regional value chains for increased food should be the target for Africa. The continent remains the region with the highest prevalence of under-nourishment. Since agriculture remains the mainstay of most African economies except the mineral producers, the sector deserves a close attention from leaders. It accounts for 65% of employment and 40% of Africa’s export earnings and accounts for 17% of the GDP. This shows how important the sector is. Agriculture needs to be seen as a conduit for farmers to get connected to markets, a conduit for revenue, for jobs and for transformation. Africa needs to come back on the international scene as food sufficient continent and even food exporter. This can be achieved only with a stable, productive agricultural resource base. Thus, achieving and sustaining food security and economic prosperity in Africa will require significant efforts to modernize the continent’s agriculture sector through injection of agribusiness and agro-industries and through the application of science and technology in agriculture. In essence, agriculture needs to be viewed as knowledge based entrepreneurial activity. Smart investments in agriculture will have multiplier effects for the whole economy and hence induce prosperity to other sectors. In recent years, a renewed focus on agriculture has been evident in policy and development agendas across the African continent. This paper outlines the status of agriculture, agribusiness and agro-industries in Africa, their role in the agenda of agricultural transformation and economic transformation and the focus on regional value chain to increase food production, transformation and trade. The paper adopts a new thinking in agriculture, which reflects a regional value chain approach. The author covers such issues as: need for agricultural transformation, the role of value chain in agricultural sector, the need for regional value chain for increased income and increased food, the role of markets and the common denominator of all, the regional integration to push forward the African agriculture agenda. Evidence shows that it is agricultural growth, through its leverage effects on the rest of the economy that typically enables poor countries, poor regions and ultimately poor households to take the first steps toward economic transformation. Therefore agricultural productivity, at the small holder’s level, has the potential to lift millions of Africa’s vulnerable out of poverty and provide sustainable jobs. Other factors, namely “the rapid urbanization” and “increased population growth”, are quoted to be of critical importance. Africa population is projected to double, attaining the 2.3 billion people mark over the next 40 years representing half of the globe’s total population. This could trigger competition for resources and can have devastating effects on natural resources if not rightly channelled.

A Food Traceability Framework Based on Permissioned Blockchain

In recent years,food safety problems have become increasingly serious.The traditional supply chain traceability solution faces some serious problems,such as centralization,data tampering,and high communication costs.To solve these problems,this paper proposes a food traceability framework based on permissioned blockchain.The proposed framework is decentralized,and the supply chain data of the framework cannot be tampered with.The framework divides supply chain entities into five organizations,and each organization deploys its own chaincode onto the blockchain.The chaincode specifies the query permission of each organization,which can effectively protect the user’s sensitive information.The PBFT consensus algorithm adopted by the framework improves the performance of processing transactions.The transactional throughput experiment shows that the proposed framework can achieve a high number of transactions per second.Query efficiency experiment demonstrates that the framework has lower query latency and good user experience.

Comparison and Experience Reference of Pork Supply Chain between China and Vietnam on the Basis of Food Safety Security

The paper aims to conduct a comprehensive analysis of theoretical model and practice on the pork supply chain of China from the perspective of logical consistency while laying emphasis on the nodes of pork supply chain and the value distribution of value chain. First of all,analyze the conceptual model of pork supply chain in China and further characterize each node of the supply chain as well as the link between the nodes. By comparing with the pork supply chain in Vietnam,analyze the characteristics and existing problems of the pork supply in China.Finally,give advice and suggestions from the aspects of supply chain process reengineering,food quality supervision and the policies & regulations etc.

Agri-food Supply Chain Management: Literature Review

The purpose of this paper is to present a critical review of prior literature relating to agri-food supply chain management. An in-depth analysis has been carried out to identify the influential information from the literature. This paper has identified gaps to be explored about agricultural supply chain management (SCM) practices which may be used by researchers to enrich theory construction and practitioners may concentrate on establishing the extent and frontiers of agri-food SCM. This research work is the first attempt to make a critical literature review of available literature on agri-food SCM practices for developing countries like India. The research articles and other materials related to the agri-food supply chain management were collected from online data bases like Scopus, EBSCO and Google Scholar for the period of 10 years (2006-2016). The study performs content analysis and is followed by descriptive analysis. In the next phase, the literature in the field of agri-food supply chain management is classified into four broad categories viz. general literature review of agri-food supply chain, policies affecting the segments of agri-food supply chain, individual segments of agri-food SCM (structure of supply chain segments and conduct of supply chain segments) and performance of supply chain segments. These four categories are comprehensively reviewed and elaborated the research gap in the literature based on agri-food supply chain management. Finally, potato supply chain of India is considered as a case example for comprehensive analysis and elaborated in detail.

Pattern Formation in Tri-Trophic Ratio-Dependent Food Chain Model

In this paper, a spatial tri-trophic food chain model with ratio-dependent Michaelis-Menten type functional response under homogeneous Neumann boundary conditions is studied. Conditions for Hopf and Turing bifurcation are derived. Sufficient conditions for the emergence of spatial patterns are obtained. The results of numerical simulations reveal the formation of labyrinth patterns and the coexistence of spotted and stripe-like patterns.

A Food Traceability System Based on Blockchain and Radio Frequency Identification Technologies

The frequent occurrence of food safety accidents at the global level has triggered consumer sensitivity. Establishing a food traceability system can effectively guarantee food safety and increase consumer confidence and satisfaction. Existing food traceability systems often ignore environmental factors that affect food quality at all stages of the supply chain, and the authenticity of the information obtained through traceability is difficult to guarantee. In this study, a food supply chain traceability model was established based on blockchain and radio frequency identification (RFID) technologies. The model focused on the traceability of environmental data during the various stages of the food supply chain and combined a centralized database and blockchain for data storage. The lot identification data of the various supply chain stages were stored in a centralized database, while the environmental data were stored in a blockchain. Thereby, the authenticity and accuracy of the traceability data were ensured. The blockchain part of the model has been simulated in the Ethereum test environment, and the experiment has achieved traceability of temperature data.

Deterministic and Stochastic Fractional-Order Hastings-Powell Food Chain Model

In this paper,a deterministic and stochastic fractional-order model of the tri-trophic food chain model incorporating harvesting is proposed and analysed.The interaction between prey,middle predator and top predator population is investigated.In order to clarify the characteristics of the proposed model,the analysis of existence,uniqueness,non-negativity and boundedness of the solutions of the proposed model are examined.Some sufficient conditions that ensure the local and global stability of equilibrium points are obtained.By using stability analysis of the fractional-order system,it is proved that if the basic reproduction number R_(0)<1,the predator free equilibrium point E_(1) is globally asymptotically stable.The occurrence of local bifurcation near the equilibrium points is investigated with the help of Sotomayor’s theorem.Some numerical examples are given to illustrate the theoretical findings.The impact of harvesting on prey and themiddle predator is studied.We conclude that harvesting parameters can control the dynamics of the middle predator.A numerical approximation method is developed for the proposed stochastic fractional-order model.

A DYNAMIC FOOD CHAIN MODEL FOR HONG KONG BASED ON RADFOOD MODEL AND BIRCHALL－JAMES ALGORITHM

In this paper a dynamic food chain model for Hong Kong which simulates the transfer of radioactive substances from a fallout deposition via the food chain into the human bodies is built. The model is based on the RADFOOD model and the BirchallJames algorithm. The radionuclides 13if and 90Sr representing the short-term and long-term risk situations have been studied as sample cases. Various types of crops,and the dietary pattern of the public have been collsidered. The resulting internal radiation doses have been calculated. The results are obtained for food consumption starting at various time after the fallout deposition and for different consumption durations.