Keep It Down: An Experimental Test of the Truncated k-Double Auction

The introduction of a centralized institution for trading production rights in quota-regulated agricultural sectors can dramatically improve the flow of information among market participants and increase efficiency. On the other hand, prevailing conditions in these small markets can provide sellers with a market advantage, yielding high quota prices that impose important financial costs on quota holders and limit the entry of new producers into the industry. In this paper, we modify the normal allocation rule of the k-double auction (kDA) to counter thin market conditions and to favor buyers who bid low prices. In laboratory experiments, we test the “truncated†kDA (T-kDA) against a regular kDA for its ability to affect buyer and seller behavior and decrease equilibrium prices, and assess how it impacts efficiency. The results show that the T-kDA significantly lowers the equilibrium price and results in moderate efficiency losses. Most importantly, the T-kDA effectively counters the market power of oligopolists when demand far outstrips supply.k-double auction, experimental economics, truncated, efficiency, commodity market, Agribusiness, Industrial Organization, Institutional and Behavioral Economics,

Keep it Down: An Experimental Test of the Truncated Uniform Price Auction

The introduction of a centralized institution for trading production rights in quota-regulated agricultural sectors can dramatically improve the flow of information among market pareticipants and increase efficiency. On the other hand, prevailing conditions in these small markets can provide sellers with a market advantage, yielding high quota prices that impose important financial costs on quota holders and limit the entry of new producers into the industry. In this paper, we modify the normal allocation rule of a uniform price auction (UPA) to favor buyers who bid low prices. In laboratory experiments, we test this “Truncated” Uniform Price Auction (T-UPA) against a regular Uniform Price Auction for its ability to decrease equilibrium prices, affect buyer and seller behavior and to assess how it impacts efficiency. The results show that the T-UPA significantly lowers the equilibrium price and results in moderate efficiency losses. Most importantly, the T-UPA effectively counters the market power of oligopolists when demand far outstrips supply. La mise en place d’une enchère centralisée pour l'échange des droits de production dans les secteurs agricoles peut considérablement améliorer le flux d'information parmi les participants au marché, ainsi qu'accroître l'efficacité. Toutefois, les conditions qui règnent dans ces petits marchés peuvent fournir aux vendeurs un avantage de marché, ce qui produit des prix de quotas élevés et limite l'entrée de nouveaux producteurs dans l'industrie. Dans cet article, nous modifions la règle de répartition normale d'une enchère de prix uniforme (UPA) afin de favoriser les acheteurs qui offrent des prix plus faibles. Dans les expériences de laboratoire, nous testons une enchère de prix uniforme «tronquée» (T-UPA) contre une enchère de prix uniforme régulière afin de tester sa capacité de diminuer les prix d'équilibre, d'influencer le comportement de l'acheteur et du vendeur, et d'évaluer son impact sur l'efficacité économique. Les résultats montrent que la T-UPA réduit considérablement le prix d'équilibre et entraîne des pertes d'efficacité modérées. Plus important encore, la T-UPA réussit à contrer le pouvoir de marché des oligopoleurs lorsque la demande dépasse largement l'offre.Auction, uniform, experimental economics, truncated, efficiency, commodity market , Enchère, uniforme, économie expérimentale, tronquée, efficacité, marché de commodité

Urgent need for a non-discriminatory and non-stigmatizing nomenclature for monkeypox virus

Free PMC article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9451062/We propose a novel, non-discriminatory classification of monkeypox virus diversity. Together with the World Health Organization, we named three clades (I, IIa and IIb) in order of detection. Within IIb, the cause of the current global outbreak, we identified multiple lineages (A.1, A.2, A.1.1 and B.1) to support real-time genomic surveillance.info:eu-repo/semantics/publishedVersio

The critical need for pooled data on coronavirus disease 2019 in African children : an AFREhealth call for action through multicountry research collaboration

Globally, there are prevailing knowledge gaps in the epidemiology, clinical manifestations, and outcomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among children and adolescents; and these gaps are especially wide in African countries. The availability of robust age-disaggregated data is a critical first step in improving knowledge on disease burden and manifestations of coronavirus disease 2019 (COVID-19) among children. Furthermore, it is essential to improve understanding of SARS-CoV-2 interactions with comorbidities and coinfections such as human immunodeficiency virus (HIV), tuberculosis, malaria, sickle cell disease, and malnutrition, which are highly prevalent among children in sub-Saharan Africa. The African Forum for Research and Education in Health (AFREhealth) COVID-19 Research Collaboration on Children and Adolescents is conducting studies across Western, Central, Eastern, and Southern Africa to address existing knowledge gaps. This consortium is expected to generate key evidence to inform clinical practice and public health policy-making for COVID-19 while concurrently addressing other major diseases affecting children in African countries.The US National Institutes of Health (NIH)/ Fogarty International Centre (FIC) to the African Forum for Research and Education in Health (AFREhealth).https://academic.oup.com/cidam2022Paediatrics and Child Healt

A year of genomic surveillance reveals how the SARS-CoV-2 pandemic unfolded in Africa.

The progression of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in Africa has so far been heterogeneous, and the full impact is not yet well understood. In this study, we describe the genomic epidemiology using a dataset of 8746 genomes from 33 African countries and two overseas territories. We show that the epidemics in most countries were initiated by importations predominantly from Europe, which diminished after the early introduction of international travel restrictions. As the pandemic progressed, ongoing transmission in many countries and increasing mobility led to the emergence and spread within the continent of many variants of concern and interest, such as B.1.351, B.1.525, A.23.1, and C.1.1. Although distorted by low sampling numbers and blind spots, the findings highlight that Africa must not be left behind in the global pandemic response, otherwise it could become a source for new variants

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance.

Investment in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing in Africa over the past year has led to a major increase in the number of sequences that have been generated and used to track the pandemic on the continent, a number that now exceeds 100,000 genomes. Our results show an increase in the number of African countries that are able to sequence domestically and highlight that local sequencing enables faster turnaround times and more-regular routine surveillance. Despite limitations of low testing proportions, findings from this genomic surveillance study underscore the heterogeneous nature of the pandemic and illuminate the distinct dispersal dynamics of variants of concern-particularly Alpha, Beta, Delta, and Omicron-on the continent. Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve while the continent faces many emerging and reemerging infectious disease threats. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats

In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Keep It Down: An Experimental Test of the Truncated k-Double Auction

The introduction of a centralized institution for trading production rights in quota-regulated agricultural sectors can dramatically improve the flow of information among market participants and increase efficiency. On the other hand, prevailing conditions in these small markets can provide sellers with a market advantage, yielding high quota prices that impose important financial costs on quota holders and limit the entry of new producers into the industry. In this paper, we modify the normal allocation rule of the k-double auction (kDA) to counter thin market conditions and to favor buyers who bid low prices. In laboratory experiments, we test the “truncated” kDA (T-kDA) against a regular kDA for its ability to affect buyer and seller behavior and decrease equilibrium prices, and assess how it impacts efficiency. The results show that the T-kDA significantly lowers the equilibrium price and results in moderate efficiency losses. Most importantly, the T-kDA effectively counters the market power of oligopolists when demand far outstrips supply

Suites opératoires des patients opérés des péritonites sur perforations du grêle à l’hôpital de la Compagnie Sucrière de Kwilu-Ngongo, en République Démocratique du Congo: Outcomes of surgery for peritonitis due to small bowel perforation at the Kwilu Ngongo ‘’Compagnie Sucrière’’ Hospital, in the Democratic Republic of Congo

Background. Small bowel perforation are an usual cause of generalized peritonitis. Surgical technics are numerous without real consensus due to various complications acounted. Data on this topic are scarce, particularly in rural areas. The present study assessed the frequency of peritonitis due to intestinal perforation and the outcome of those patients during postoperative period. Methods. 39 records of patients admitted at the Kwilu-Ngungu Compagnie Sucrière Hospital from 2004 to 2015 for generalized peritonitis due to non-traumatic intestinal perforation where included. Clinical data (age, sex), surgical protocols (surgical technique, postoperative complications, evolution, digestive sutures) and outcome (survivor, death) were recorded. Fisher's exact or chi square tests were used to compare the proportions as appropriated. Results. Peritonitis following intestinal perforation accounts for 37.1% of all generalized peritonitis cases. Male patients were predominant (64%), and the mean age of the studied population was 19.5 years (range 3-60 years). The surgical techniques consisted mainly of excision-suture and intestinal resection followed by a terminal-terminal anastomosis with external mucosal sutures. The recorded complications occurred in 31/39 patients, more frequently in those with a poor preoperative general health conditions (64.7%). Superficial parietal infections were more frequent thant deep ones (43.5% vs 15.4%); postoperative peritonitis from digestive suture release were observed in 20.5% of subjects. Digestive suture releases occurred more frequently in patients who underwent resection and anastomis versus the group of abrasion and suture (60.2% vs 6.2%; p = 0.002). The overall mortality rate was 13%. Out of five deceased patients, three had developed a newly postoperative peritonitis. Conclusion. First-line excision-suture seems to give a better result (fewer parietal infections and digestive sutures) compared to resection-anastomosis as a surgical technique for peritonitis on intestinal perforation. However, more elaborate studies (randomized, large and multicentric) should be planned to better demonstrate the performance of each surgical approach. Contexte. Les perforations de l’intestin grêle sont une cause habituelle des péritonites généralisées et les complications post-opératoires sont fréquentes. Diverses techniques ont été décrites pour leur traitement, sans réel consensus de performance. L’ampleur du problème est loin d’être établi, surtout en milieu rural. La présente étude évalue la fréquence de la péritonite post-perforation intestinale et l’issue des patients opérés. Méthodes. L’étude retrospective a inclus 39 dossiers des patients  opérés pour péritonite  sur perforation  non traumatique du grêle  entre 2004 et 2015, à l’hôpital de la compagnie sucrière de Kwilu-Ngongo. Les données cliniques (âge, sexe), chirurgicales (technique chirurgicale : excision suture vs résection anastomose, complications post opératoires, évolution de la plaie, lâchage des sutures digestives) et l’issue vitale (survivant, décès) ont été considérées. Les tests de chi carré ou exact de Fisher ont été utilisés pour comparer les proportions selon les cas. Résultats. Les péritonites sur perforation intestinale rendaient compte de 37,1% des cas de toutes les péritonites généralisées. Les sujets du sexe masculin étaient plus nombreux (64%) et l’âge moyen était de 19,5 ans (extrêmes de 3-60 ans). Les techniques chirurgicales utilisées pour les perforations comprenaient essentiellement l’excision-suture et la résection intestinale suivie d’une anastomose termino-terminale avec des sutures extramuqueuses extériorisées. Des complications postopératoires sont survenues chez 31 opérés,  affectant surtout les sujets en mauvais état général pré-opératoire. Elles ont été essentiellement : des infections pariétales superficielles (43,5%), des infections pariétales profondes (15,4%) et des péritonites postopératoires sur lâchage de suture digestive (20,5%). Les lachâges des sutures ont affectés surtout le groupe des sujets  versusn celui des patients soumis à l’avivement-suture (60,2% vs 6,2% ; p=0,002). Le taux global de mortalité  était de 13%. Trois sur les cinq patients décédés étaient des cas repris pour péritonite post opératoire. Conclusion. L’excision-suture en première intention semble donner un meilleur résultat (moins d’infections pariétales et de lâchage de sutures digestives) par rapport à la résection-anastomose comme technique chirurgicale des péritonites sur perforation intestinale. Toutefois, des études plus élaborées (randomisées, grande taille et multicentriques) sont à envisager pour mieux illuster la performance de chaque approche chirurgicale