Pub Date : 1900-01-01DOI: 10.4074/S1966960711001032
B. Lelyon, V. Chatellier, K. Daniel
In this paper, we discuss the cross-effects on the productive strategy of French dairy farms due to the decoupling and to price variation. A model based on mathematical programming has been developed to determine how dairy farmers might re-evaluate their systems to identify an optimal production plan. The model is applied to four types of dairy farms in order to analyze the impact of the reform depending on farm’s activities. The simulations point out how the implementation of the decoupling encourages farmers to increase the share of grassland. However, the increase in cereal prices is a strong incentive to intensify forage production to free up land for crop production. Finally, after four years of decoupling, this study helps to put into perspective the theoretical effects of decoupling and the actual choices made by farmers. This article identifies six factors which could explain these differences: the longterm production requirements, the eligibility criteria for the direct payment, the sociology/psychology of the farmer, the anticipation of a new reform, the trade organization and the value of property assets.
{"title":"Decoupling and prices: determinant of dairy farmers’ choices?","authors":"B. Lelyon, V. Chatellier, K. Daniel","doi":"10.4074/S1966960711001032","DOIUrl":"https://doi.org/10.4074/S1966960711001032","url":null,"abstract":"In this paper, we discuss the cross-effects on the productive strategy of French dairy farms due to the decoupling and to price variation. A model based on mathematical programming has been developed to determine how dairy farmers might re-evaluate their systems to identify an optimal production plan. The model is applied to four types of dairy farms in order to analyze the impact of the reform depending on farm’s activities. The simulations point out how the implementation of the decoupling encourages farmers to increase the share of grassland. However, the increase in cereal prices is a strong incentive to intensify forage production to free up land for crop production. Finally, after four years of decoupling, this study helps to put into perspective the theoretical effects of decoupling and the actual choices made by farmers. This article identifies six factors which could explain these differences: the longterm production requirements, the eligibility criteria for the direct payment, the sociology/psychology of the farmer, the anticipation of a new reform, the trade organization and the value of property assets.","PeriodicalId":170092,"journal":{"name":"Revue d’études en Agriculture et Environnement","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128385116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Le monde agricole a longtemps ete caracterise par une relative fermeture sur lui-meme. Fermeture professionnelle qui laisse peu de place aux nouveaux entrants d’origines sociales diverses, fermeture conjugale avec un choix relativement circonscrit aux filles d’agriculteur et restreint par la demographie des campagnes. La montee de l’heterogamie, non seulement professionnelle (les femmes travaillent de plus en plus a l’exterieur de l’exploitation) mais sociale (les femmes sont de moins en moins issues du milieu agricole), remet en question cette image. Cette ouverture conjugale n’est pas uniforme : les agriculteurs des secteurs les plus specialises, comme la cerealiculture, sont plus enclins a avoir une conjointe exterieure a l’agriculture ; elle sera la partenaire dans une vie familiale qui ne se confondra pas avec celle de l’exploitation. Dans les secteurs moins specialises – comme les systemes de polyculture elevage ou dans la production de lait avec un fort travail d’astreinte – ils ont plus tendance a avoir des conjointes filles d’agriculteurs qui travaillent avec eux, bref des collaboratrices dans une vie familiale centree sur le travail.
{"title":"Les choix des conjoints en agriculture","authors":"C. Giraud, J. Rémy","doi":"10.3406/reae.2008.1946","DOIUrl":"https://doi.org/10.3406/reae.2008.1946","url":null,"abstract":"Le monde agricole a longtemps ete caracterise par une relative fermeture sur lui-meme. Fermeture professionnelle qui laisse peu de place aux nouveaux entrants d’origines sociales diverses, fermeture conjugale avec un choix relativement circonscrit aux filles d’agriculteur et restreint par la demographie des campagnes. La montee de l’heterogamie, non seulement professionnelle (les femmes travaillent de plus en plus a l’exterieur de l’exploitation) mais sociale (les femmes sont de moins en moins issues du milieu agricole), remet en question cette image. Cette ouverture conjugale n’est pas uniforme : les agriculteurs des secteurs les plus specialises, comme la cerealiculture, sont plus enclins a avoir une conjointe exterieure a l’agriculture ; elle sera la partenaire dans une vie familiale qui ne se confondra pas avec celle de l’exploitation. Dans les secteurs moins specialises – comme les systemes de polyculture elevage ou dans la production de lait avec un fort travail d’astreinte – ils ont plus tendance a avoir des conjointes filles d’agriculteurs qui travaillent avec eux, bref des collaboratrices dans une vie familiale centree sur le travail.","PeriodicalId":170092,"journal":{"name":"Revue d’études en Agriculture et Environnement","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126773028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"La résilience en débat : quel devenir pour les agriculteurs en difficulté ?","authors":"Benoît Lallau, Estelle Thibaut","doi":"10.3406/reae.2009.1963","DOIUrl":"https://doi.org/10.3406/reae.2009.1963","url":null,"abstract":"","PeriodicalId":170092,"journal":{"name":"Revue d’études en Agriculture et Environnement","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114301657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The volatility of hog prices is high compared to most agricultural commodities. However, European hog producers do not benefit from any agricultural policy support. Through the continuous production process and induced selling activity on spot markets, producers benefit from a natural moving average product pricing. In addition, asymmetric price risk management is able to increase the expected utility of risk adverse hog producers. But, if there is a futures contract at the European Exchange (EUREX), there is no option market and as a consequence no derivative contracts on the European hog market. The article is presenting how financial intermediaries could offer an innovative derivative contract to complement the “naturall ” steady price of the French hog producers.
{"title":"An option on the average European futures prices for an efficient hog producer risk management","authors":"Martial Phélippé-Guinvarc'h, J. Cordier","doi":"10.3406/reae.2010.1937","DOIUrl":"https://doi.org/10.3406/reae.2010.1937","url":null,"abstract":"The volatility of hog prices is high compared to most agricultural commodities. However, European hog producers do not benefit from any agricultural policy support. Through the continuous production process and induced selling activity on spot markets, producers benefit from a natural moving average product pricing. In addition, asymmetric price risk management is able to increase the expected utility of risk adverse hog producers. But, if there is a futures contract at the European Exchange (EUREX), there is no option market and as a consequence no derivative contracts on the European hog market. The article is presenting how financial intermediaries could offer an innovative derivative contract to complement the “naturall ” steady price of the French hog producers.","PeriodicalId":170092,"journal":{"name":"Revue d’études en Agriculture et Environnement","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122699759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Partant de la situation actuelle de la profession veterinaire en Suisse, notre contribution rend compte du travail de redefinition identitaire que des professionnels operent lorsque le coeur traditionnel de leurs activites et certains fondements de leur metier, voire de leur prestige, sont remis en question. Parallelement, elle examine comment les femmes s’installent dans une profession qualifiee, au moment ou celle-ci est contrainte de (re)legitimer son role social. La profession veterinaire est confrontee a deux changements concomitants : les femmes arrivent en nombre, en meme temps que les specialisations se recomposent, les animaux d’elevage perdant du terrain au profit des animaux de compagnie. Or, les relations entre ces deux phenomenes ne sont pas de cause a effet. Le processus de feminisation en cours pourrait meme paraitre comme atypique, la specialite connotee comme la plus masculine se trouvant supplantee par le secteur en expansion des animaux de compagnie, dans lequel s’investissent les femmes. Cette hypothese est toutefois a relativiser car la reconnaissance et la legitimite dont beneficie la specialisation « animaux de compagnie » reste fragile.
{"title":"Les bouleversements de la profession vétérinaire. Lorsque la recherche d'une nouvelle légitimité sociale coïncide avec l'arrivée des femmes","authors":"M. Surdez","doi":"10.3406/reae.2009.1984","DOIUrl":"https://doi.org/10.3406/reae.2009.1984","url":null,"abstract":"Partant de la situation actuelle de la profession veterinaire en Suisse, notre contribution rend compte du travail de redefinition identitaire que des professionnels operent lorsque le coeur traditionnel de leurs activites et certains fondements de leur metier, voire de leur prestige, sont remis en question. Parallelement, elle examine comment les femmes s’installent dans une profession qualifiee, au moment ou celle-ci est contrainte de (re)legitimer son role social. La profession veterinaire est confrontee a deux changements concomitants : les femmes arrivent en nombre, en meme temps que les specialisations se recomposent, les animaux d’elevage perdant du terrain au profit des animaux de compagnie. Or, les relations entre ces deux phenomenes ne sont pas de cause a effet. Le processus de feminisation en cours pourrait meme paraitre comme atypique, la specialite connotee comme la plus masculine se trouvant supplantee par le secteur en expansion des animaux de compagnie, dans lequel s’investissent les femmes. Cette hypothese est toutefois a relativiser car la reconnaissance et la legitimite dont beneficie la specialisation « animaux de compagnie » reste fragile.","PeriodicalId":170092,"journal":{"name":"Revue d’études en Agriculture et Environnement","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123035733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
[paper in French] This paper focuses on the trajectory of the BCG vaccine used against bovine tuberculosis in France between 1921 and 1963. It shows how public health issues related to this disease are intimately linked with other issues, whether professional, industrial or of political economy. First, it analyses the way the Pasteur Institute, veterinarians and farmers got mobilized to transform the French legislation in order to gain more direct responsibilities in the control of bovine tuberculosis between 1930 and 1950. Second, it studies how farmers’ appropriation of prophylactic techniques contributed to redefine the sanitary policy against this disease in a global context of agricultural modernization promoted by the post-war French government, whereas at the same time, the new research orientation of the Pasteur Institute led to the abandon of the veterinary vaccine.
{"title":"La vaccination des bovidés contre la tuberculose en France, 1921-1963 : entre modèle épistémique et alternative à l'abattage","authors":"Delphine Berdah","doi":"10.3406/reae.2010.1994","DOIUrl":"https://doi.org/10.3406/reae.2010.1994","url":null,"abstract":"[paper in French] This paper focuses on the trajectory of the BCG vaccine used against bovine tuberculosis in France between 1921 and 1963. It shows how public health issues related to this disease are intimately linked with other issues, whether professional, industrial or of political economy. First, it analyses the way the Pasteur Institute, veterinarians and farmers got mobilized to transform the French legislation in order to gain more direct responsibilities in the control of bovine tuberculosis between 1930 and 1950. Second, it studies how farmers’ appropriation of prophylactic techniques contributed to redefine the sanitary policy against this disease in a global context of agricultural modernization promoted by the post-war French government, whereas at the same time, the new research orientation of the Pasteur Institute led to the abandon of the veterinary vaccine.","PeriodicalId":170092,"journal":{"name":"Revue d’études en Agriculture et Environnement","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129193485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
[paper in French] Open-access is probably the main cause of crowding on recreational sites, especially when they are attractive and close to urban areas. In this case, theory predicts equilibrium and optimum differ due to externality of congestion. Whereas Fisher and Krutilla (1972) caracterized optimum and equilibrium in monosite models, recent works on congestion in multiple sites models (Random Utility Models) only study equilibrium and the repartition of visits between sites in an empirical way. Our theoretical framework allows us to go further and derive visitation equilibrium and visitation optimum in a two sites Random Utility Model with participation. Sites differ by quality. We use a recent measure of welfare (Erlander, 2005), essential to calculate optimum. At equilibrium, we show that participation is too high and that the high quality site is too much visited. We introduce optimal taxes to resolve this issue. Because this solution does not appear very realistic in the French case, we also examine impacts of improvements of quality on welfare. An illustration is finally proposed with a multinomial logit model estimated with data on recreational fishing
{"title":"La valeur récréative de la forêt en France : une approche par les coûts de déplacement","authors":"S. Garcia, J. Jacob","doi":"10.3406/reae.2010.1938","DOIUrl":"https://doi.org/10.3406/reae.2010.1938","url":null,"abstract":"[paper in French] Open-access is probably the main cause of crowding on recreational sites, especially when they are attractive and close to urban areas. In this case, theory predicts equilibrium and optimum differ due to externality of congestion. Whereas Fisher and Krutilla (1972) caracterized optimum and equilibrium in monosite models, recent works on congestion in multiple sites models (Random Utility Models) only study equilibrium and the repartition of visits between sites in an empirical way. Our theoretical framework allows us to go further and derive visitation equilibrium and visitation optimum in a two sites Random Utility Model with participation. Sites differ by quality. We use a recent measure of welfare (Erlander, 2005), essential to calculate optimum. At equilibrium, we show that participation is too high and that the high quality site is too much visited. We introduce optimal taxes to resolve this issue. Because this solution does not appear very realistic in the French case, we also examine impacts of improvements of quality on welfare. An illustration is finally proposed with a multinomial logit model estimated with data on recreational fishing","PeriodicalId":170092,"journal":{"name":"Revue d’études en Agriculture et Environnement","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129546959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
– Developper le potentiel d’adoption des matieres organiques pour ameliorer les productions agricoles revient a conferer a l’agriculture une nouvelle fonction et a integrer la question environnementale a l’exercice du metier d’agriculteur. Que se passe-t-il lors de la rencontre entre le projet d’associer l’agriculture a la gestion des dechets de la ville et les publics auxquels il s’adresse ? A quelles conditions l’agriculture periurbaine peut-elle contribuer a integrer les enjeux environnementaux qui lui sont assignes ?
{"title":"La valorisation des matières organiques de la ville. Le cas des petits maraîchers de la zone périurbaine de Dakar","authors":"M. Zélem","doi":"10.22004/AG.ECON.188237","DOIUrl":"https://doi.org/10.22004/AG.ECON.188237","url":null,"abstract":"– Developper le potentiel d’adoption des matieres organiques pour ameliorer les productions agricoles revient a conferer a l’agriculture une nouvelle fonction et a integrer la question environnementale a l’exercice du metier d’agriculteur. Que se passe-t-il lors de la rencontre entre le projet d’associer l’agriculture a la gestion des dechets de la ville et les publics auxquels il s’adresse ? A quelles conditions l’agriculture periurbaine peut-elle contribuer a integrer les enjeux environnementaux qui lui sont assignes ?","PeriodicalId":170092,"journal":{"name":"Revue d’études en Agriculture et Environnement","volume":"18 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133847256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Janvier 2008, les negociations multilaterales a l’Organisation mondiale du commerce (OMC) sont toujours bloquees sur le chapitre agricole. La pression internationale est forte sur l’Union europeenne (UE) pour qu’elle ouvre plus largement ses marches agricoles alors que celle-ci craint que cela ne conduise a remettre en cause son modele agricole europeen. En parallele, l’UE propose de developper l’utilisation des biocarburants dans les activites europeennes de transport terrestre, ce qui aurait un effet benefique pour son secteur agricole. L’objectif general de cet article est d’evaluer empiriquement les effets de ces deux scenarios pour apprecier dans quelle mesure la politique europeenne de promotion des biocarburants pourrait faciliter un accord agricole a l’OMC en attenuant ses effets redoutes. Ces evaluations sont conduites avec un modele d’equilibre general calculable qui permet d’en mesurer les impacts sur les differents secteurs agricoles et agroalimentaires europeens. Les resultats attendus des simulations montrent les effets benefiques du developpement des biocarburants et negatifs d’un accord a l’OMC sur les revenus agricoles europeens. Ils montrent surtout qu’en valeur absolue les seconds effets dominent les premiers et qu’ils sont tres contrastes entre les differents secteurs. Enfin, les analyses montrent l’attention qui doit etre portee a la definition des produits sensibles en fonction de la situation des marches: l’interet du secteur agricole europeen serait en particulier de retenir le bioethanol dans les produits sensibles a la place du sucre
{"title":"La sélection des produits agricoles sensibles : le cas européen","authors":"Alexandre Gohin","doi":"10.3406/reae.2008.2087","DOIUrl":"https://doi.org/10.3406/reae.2008.2087","url":null,"abstract":"Janvier 2008, les negociations multilaterales a l’Organisation mondiale du commerce (OMC) sont toujours bloquees sur le chapitre agricole. La pression internationale est forte sur l’Union europeenne (UE) pour qu’elle ouvre plus largement ses marches agricoles alors que celle-ci craint que cela ne conduise a remettre en cause son modele agricole europeen. En parallele, l’UE propose de developper l’utilisation des biocarburants dans les activites europeennes de transport terrestre, ce qui aurait un effet benefique pour son secteur agricole. L’objectif general de cet article est d’evaluer empiriquement les effets de ces deux scenarios pour apprecier dans quelle mesure la politique europeenne de promotion des biocarburants pourrait faciliter un accord agricole a l’OMC en attenuant ses effets redoutes. Ces evaluations sont conduites avec un modele d’equilibre general calculable qui permet d’en mesurer les impacts sur les differents secteurs agricoles et agroalimentaires europeens. Les resultats attendus des simulations montrent les effets benefiques du developpement des biocarburants et negatifs d’un accord a l’OMC sur les revenus agricoles europeens. Ils montrent surtout qu’en valeur absolue les seconds effets dominent les premiers et qu’ils sont tres contrastes entre les differents secteurs. Enfin, les analyses montrent l’attention qui doit etre portee a la definition des produits sensibles en fonction de la situation des marches: l’interet du secteur agricole europeen serait en particulier de retenir le bioethanol dans les produits sensibles a la place du sucre","PeriodicalId":170092,"journal":{"name":"Revue d’études en Agriculture et Environnement","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133552217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Some consumers are willing to pay extra for food if it is of domestic origin. This paper theoretically examines the consequences of such home biased behavior for agricultural policy, assuming that the policy is decided by the median voter. The analysis is conducted in the framework of a small open economy, with a Ricardian production structure. Consumers differ with respect to how much extra they are willing to pay for a domestically produced agricultural good. For a tariff we find that, if there would be some home biased choices (no matter how few) in a laissez-faire regime, the political equilibrium will imply a strictly positive tariff. This tariff is high if the productivity in the agricultural sector of this country is low. A political equilibrium with a strictly positive subsidy requires stronger home bias than a tariff.
{"title":"Home bias in preferences and the political economics of agricultural protection","authors":"Clas Eriksson","doi":"10.3406/reae.2011.1879","DOIUrl":"https://doi.org/10.3406/reae.2011.1879","url":null,"abstract":"Some consumers are willing to pay extra for food if it is of domestic origin. This paper theoretically examines the consequences of such home biased behavior for agricultural policy, assuming that the policy is decided by the median voter. The analysis is conducted in the framework of a small open economy, with a Ricardian production structure. Consumers differ with respect to how much extra they are willing to pay for a domestically produced agricultural good. For a tariff we find that, if there would be some home biased choices (no matter how few) in a laissez-faire regime, the political equilibrium will imply a strictly positive tariff. This tariff is high if the productivity in the agricultural sector of this country is low. A political equilibrium with a strictly positive subsidy requires stronger home bias than a tariff.","PeriodicalId":170092,"journal":{"name":"Revue d’études en Agriculture et Environnement","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130564988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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