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1.
Conserv Biol ; 38(5): e14358, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39248733

RESUMEN

Monitoring wildlife trade dynamics is an important initial step for conservation action and demand reduction campaigns to reduce illegal wildlife trade. Studies often rely on one data source to assess a species' trade, such as seizures or the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) trade data. Each database provides useful information but is often incomplete. Combining information from multiple sources helps provide a more complete understanding of trade. A recent rapid increase in demand for helmeted hornbill (Rhinoplax vigil) casques (a brightly colored, solid keratinous rostrum) led to its uplisting to critically endangered on the International Union for Conservation of Nature Red List in 2015. However, there is little current information on what factors influence trade trends and what current levels of demand are. We combined data from CITES, seizure records, and previously underused, yet abundant, art and antique auction data to examine the global trade in helmeted hornbill casque products (HHPs). Three decades of auction data revealed that 1027 individual HHPs had been auctioned since 1992; total auction sales were over US$3 million from 1992 to 2021. The number of HHPs auctioned was greatest from 2011 to 2014, just after the global art boom (2009-2011), followed by a decline in volume and price. The auction data also revealed 2 possible markets for HHPs: true antique and speculative, defined by era, price, and trade patterns. Trends in illegal trade matched those of the auction market, but legal trade remained consistently low. Combining data sources from legal, illegal, and gray markets provided an overview of the dynamics of illegal trade in an endangered species. This approach can be applied to other wildlife markets to provide a more complete understanding of trade and demand at the market level to inform future demand reduction campaigns.


Análisis del comercio ornamental legal, ilegal y gris del cálao con casco, especie en peligro crítico Resumen El monitoreo de la dinámica del comercio de especies silvestres es un paso inicial importante para las acciones de conservación y las campañas de reducción de la demanda destinadas a reducir el comercio ilegal de especies silvestres. Los estudios suelen basarse en una sola fuente de datos para evaluar el comercio de una especie, como las incautaciones o los datos comerciales de la Convención sobre el Comercio Internacional de Especies Amenazadas de Fauna y Flora Silvestres (CITES). Cada base de datos proporciona información útil, pero a menudo incompleta. La combinación de información procedente de varias fuentes ayuda a comprender mejor el comercio. Un reciente y rápido aumento de la demanda de cascos (un casquete queratinoso, sólido y de colores brillantes) de cálao con casco (Rhinoplax vigil) hizo que en 2015 se incluyera en la Lista Roja de la Unión Internacional para la Conservación de la Naturaleza como especie en peligro crítico. Sin embargo, existe poca información actual sobre los factores que influyen en las tendencias del comercio y cuáles son los niveles actuales de demanda. Combinamos datos de CITES, registros de incautaciones y datos de subastas de arte y antigüedades previamente poco utilizados, aunque abundantes, para examinar el comercio mundial de productos de casquetes de cálao con casco (CCC). Tres décadas de datos de subastas revelaron que se habían subastado 1,027 CCC individuales desde 1992; las ventas totales en subasta superaron los tres millones de dólares entre 1992 y 2021. El número de CCC subastados fue mayor entre 2011 y 2014, justo después del boom del arte (2009­2011), seguido de un descenso en volumen y precio. Los datos de las subastas también revelaron dos posibles mercados para los CCC: el de las verdaderas antigüedades y el especulativo, definidos por la época, el precio y los patrones de comercio. Las tendencias del comercio ilegal coincidieron con las del mercado de subastas, pero el comercio legal se mantuvo bajo con constancia. Con la combinación de fuentes de datos de mercados legales, ilegales y grises, nuestros datos proporcionaron una visión general de la dinámica del comercio ilegal de una especie amenazada. Este enfoque puede aplicarse a otros mercados de especies silvestres para obtener un conocimiento más completo del comercio y la demanda a nivel de mercado que sirva de base a futuras campañas de reducción de la demanda.


Asunto(s)
Comercio , Conservación de los Recursos Naturales , Especies en Peligro de Extinción , Especies en Peligro de Extinción/legislación & jurisprudencia , Conservación de los Recursos Naturales/legislación & jurisprudencia , Animales , Comercio/legislación & jurisprudencia , Crimen/prevención & control
2.
Appetite ; 203: 107687, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39307463

RESUMEN

The growing number of athletes in the population leads to an increasing demand for high-protein functional foods to which food industries are trying to respond with new products and strategies that can meet the needs of athletes. An experimental auction was performed to elicit athletes' willingness to pay for an innovative high-protein bread, correlating it to specific food values. For a deeper understanding of the determinants of respondents' choices for high-protein bread and preferences regarding food values, the combination of Best-Worst Scaling and Cluster Analysis was used. The Cluster Analysis identified five different groups of athletes, each characterised by specific preferences and willingness to pay. Participants with high attention for the nutritional aspect and needs related to sports activity, are willing to pay more than the other ones. The investigated issue is crucial for customizing marketing strategies and meeting the needs of different athlete segments.

3.
PeerJ Comput Sci ; 10: e2159, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39145250

RESUMEN

In the contemporary digitalization landscape and technological advancement, the auction industry undergoes a metamorphosis, assuming a pivotal role as a transactional paradigm. Functioning as a mechanism for pricing commodities or services, the procedural intricacies and efficiency of auctions directly influence market dynamics and participant engagement. Harnessing the advancing capabilities of artificial intelligence (AI) technology, the auction sector proactively integrates AI methodologies to augment efficacy and enrich user interactions. This study delves into the intricacies of the price prediction challenge within the auction domain, introducing a sophisticated RL-GRU framework for price interval analysis. The framework commences by adeptly conducting quantitative feature extraction of commodities through GRU, subsequently orchestrating dynamic interactions within the model's environment via reinforcement learning techniques. Ultimately, it accomplishes the task of interval division and recognition of auction commodity prices through a discerning classification module. Demonstrating precision exceeding 90% across publicly available and internally curated datasets within five intervals and exhibiting superior performance within eight intervals, this framework contributes valuable technical insights for future endeavours in auction price interval prediction challenges.

4.
J Anim Sci Technol ; 66(4): 834-845, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39165741

RESUMEN

Currently, in pork auctions in Korea, only carcass weight and backfat thickness provide information on meat quantity, while the production volume of primal cuts and fat contents remains largely unknown. This study aims to predict the production of primal cuts in pigs and investigate how these carcass traits affect pricing. Using the VCS2000, the production of shoulder blade, loin, belly, shoulder picnic, and ham was measured for gilts (17,257 pigs) and barrows (16,365 pigs) of LYD (Landrace × Yorkshire × Duroc) pigs. Single and multiple regression analysis were conducted to analyze the relationship between the primal cuts and carcass weight. The study also examined the correlation between each primal cut, backfat thickness (1st thoracic vertebra backfat thickness, grading backfat thickness, and Multi-brached muscle middle backfat thickness), pork belly fat percentage, total fat yield, and auction price. A multiple regression analysis was conducted between the carcass traits that showed a high correlation and the auction price. After conducting a single regression analysis on the primal cuts of gilt and barrow, all coefficients of determination (R2) were 0.77 or higher. In the multiple regression analysis, the R2 value was 0.98 or higher. The correlation coefficient between the carcass weights and the auction price exceeded 0.70, while the correlation coefficients between the primal cuts and the auction prices were above 0.65. In terms of fat content, the backfat thickness of gilt exhibited a correlation coefficient of 0.70, and all other items had a correlation coefficient of 0.47 or higher. The correlation coefficients between the Forequarter, Middle, and Hindquarter and the auction price were 0.62 or higher. The R2 values of the multiple regression analysis between carcass traits and auction price were 0.5 or higher for gilts and 0.4 or higher for barrows. The regression equations between carcass weight and primal cuts derived in this study exhibited high determination coefficients, suggesting that they could serve as reliable means to predict primal cut production from pig carcasses. Elucidating the correlation between primal cuts, fat contents and auction prices can provide economic indicators for pork and assist in guiding the direction of pig farming.

5.
J Anim Sci ; 1022024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-39212666

RESUMEN

Stress during the transition of beef steers from ranch to feedlot may depend on steer source and preconditioning. The interplay between physiological and behavioral patterns of preconditioned (PC) and auction-derived (AD) steers, particularly after commingling, is poorly understood. Our objective was to evaluate whether hair cortisol (HC) concentrations were related to the health and performance of PC and AD steers and study behavioral activities after commingling over 6 wk in a feedlot. Steers, sourced either from ranch (PC, n = 250) or local auction (AD, n = 250), were assigned into 1 of 5 pens, 100% PC (100PC); 75% PC 25% AD (75PC); 50% PC 50% AD (50PC); 25% PC 75% AD (25PC), and 100% AD (0PC), each pen containing 100 steers. Pen was the experimental unit and individual steers were the observational unit where physiological and behavioral changes were measured. The study subsampled 225 steers (PC = 113 and AD = 112) which were equipped with CowManager ear tags to record behaviors. On day 40, hair samples from each steer were collected by clipping hair close to the skin. Data were analyzed using multiple linear, logistic regression, or multilevel negative binomial regression models depending on the outcomes. There was no difference in HC concentrations (day 40) between PC and AD steers (P = 0.66), and no association with Bovine Respiratory Disease (BRD)-related morbidity (P = 0.08) or average daily gain (ADG) (P = 0.44). After adjusting for source and commingling effects, HC concentrations did not affect time spent eating (P = 0.83), ruminating (P = 0.20), active (P = 0.89), or non-active (P = 0.32). PC steers spent more time eating and ruminating over weeks 1 to 4 (P < 0.01) and weeks 1 to 3, respectively (P < 0.05), and more time being active over weeks 1 and 2 compared to AD steers (P < 0.001), but less time being non-active than AD steers on weeks 1 to 3 (P < 0.001). Steers in 100PC and 50PC pens spent more time eating than steers in 0PC (P < 0.001), whereas steers in 25PC spent less time eating than steers in 0PC (P < 0.001). Steers in 0PC spent the most time being not active (P < 0.01). In conclusion, preconditioned steers spent more time eating, ruminating, and being active and less time being not active over the first 3 wk in the feedlot, regardless of commingling. The HC concentrations did not identify potentially lower stress related to ranch transfer and were neither associated with BRD-related morbidity nor ADG.


Preconditioning constitutes management practices that help reduce steers' transition-related stress from a ranch to a feedlot. Auction-derived (AD) steers, generally exposed to various stressors over a short period, are often commingled with preconditioned (PC) steers in feedlots for homogeneity. The present study examined the physiological and behavioral changes in PC and AD steers when commingled in various proportions during the first 6 wk in the feedlot. Our study found that PC steers exhibited favorable behaviors, spending more time eating, ruminating, and being active compared to AD steers, irrespective of commingling. However, hair cortisol concentrations did not identify steers experiencing lower ranch transfer-related stress, disease, or poor growth performance.


Asunto(s)
Conducta Animal , Cabello , Hidrocortisona , Estrés Fisiológico , Animales , Bovinos/fisiología , Masculino , Hidrocortisona/metabolismo , Hidrocortisona/análisis , Cabello/química , Conducta Animal/fisiología , Crianza de Animales Domésticos/métodos
6.
J Environ Manage ; 365: 121547, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38941850

RESUMEN

This paper studies the effect of Green Public Procurement (GPP) on competition, bids, and winning bids under two different regulation periods where the latter include more explicitly expressed GPP ambitions. Based on detailed data from Swedish internal cleaning service procurements, our results imply that environmental considerations might not influence the bids as required for GPP to be considered an effective environmental policy instrument. Over time, lower degree of competition and increased bids are found. This phenomenon can be attributed, at least in part, to regulatory influences, signifying an escalating complexity in the process of submitting bids.


Asunto(s)
Política Ambiental , Suecia , Comercio
7.
Sensors (Basel) ; 24(7)2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38610248

RESUMEN

IoT (Internet-of-Things)-powered devices can be exploited to connect vehicles to smart city infrastructure, allowing vehicles to share their intentions while retrieving contextual information about diverse aspects of urban viability. In this paper, we place ourselves in a transient scenario in which next-generation vehicles that are able to communicate with the surrounding infrastructure coexist with traditional vehicles with limited or absent IoT capabilities. We focus on intersection management, in particular on reusing existing traffic lights empowered by a new management system. We propose an auction-based system in which traffic lights are able to exchange contextual information with vehicles and other nearby traffic lights with the aim of reducing average waiting times at intersections and consequently overall trip times. We use bid propagation to improve standard vehicle trip times while allowing emergency vehicles to free up the way ahead without needing ad hoc system for such vehicle, only an increase in their budget. The proposed system is then tested against two baselines: the classical Fixed Time Control system currently adopted for traffic lights, and an auction strategy that does not exploit traffic light coordination. We performed a large set of experiments using the well known MATSim transport simulator on both a synthetic Manhattan map and on a map we built of an urban area located in Modena, Northern Italy. Our results show that the proposed approach performs better than the classical fixed time control system and the auction strategy that does not exploit coordination among traffic lights.

8.
Cent Eur J Oper Res ; 32(2): 241-266, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38650678

RESUMEN

Combinatorial auctions are an important part of many frameworks for carrier collaboration in logistics. In the last years, many innovative auction mechanisms have been developed in the economic literature that could potentially be applied in this context and that could significantly simplify the process of determining efficient allocations of requests. These mechanisms rely on certain assumptions about the valuations of bidders. In this paper, we perform computational experiments to analyze to which extent these requirements are fulfilled for valuations derived from a simple logistics problem, the Traveling Salesman Problem. We find that bidders' valuations typically violate even very elementary requirements, but that these violations affect only a limited number of request bundles. We further analyze whether these violations exhibit a consistent pattern across multiple carriers and check consistency if route lengths are calculated exactly or approximated. Supplementary Information: The online version contains supplementary material available at 10.1007/s10100-023-00873-1.

9.
Environ Sci Pollut Res Int ; 31(8): 11968-11982, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38227258

RESUMEN

The construction land quota pricing mechanism with cost plus pricing method is not sufficient to reflect its intrinsic value. This diminishes the willingness of farmers to voluntarily reclaim abandoned residential and other rural construction land, leading to suboptimal efficiency in rural land utilization and an excessive squandering of rural land resources. Thus, a sequential auction model with two stages for complementary goods was constructed, which considered the synergic characteristics between the land and quota. Further, regret psychology of bidder was considered in the case of winning or losing. A rational pricing mechanism has been developed to allocate construction land quotas, aiming to enhance farmers' motivation to the vacant homesteads of reclamation and revitalizing the stock of rural construction land. The results revealed that the regret psychology in the case of winning would decrease the transaction price of the quota, i.e., the greater the perceived regret in the case of winning, the more significant the reduction in the bidding price offered. Moreover, the regret psychology in the event of losing/failure would increase the transaction price of quota. Furthermore, publishing only the winner's price after the auction leads to the highest price of the quota offered by the bidder. In contrast, publishing only the loser's bidding price leads to the lowest transaction price of the quota offered by the bidder. In addition, the fee for delayed construction would increase the bidding price of the construction land quota. Therefore, local governments should consider announcing only the winner of price after the quota auction has ended. In addition, imposing a fee for delayed construction would enhance the transaction price of land quota, increase farmers' revenue from land reclamation, and incentivize farmers to reclaim unused rural land.


Asunto(s)
Agricultores , Asignación de Recursos , Humanos , China , Costos y Análisis de Costo , Emociones
10.
Artículo en Inglés | MEDLINE | ID: mdl-38037646

RESUMEN

Peer-to-peer (P2P) energy trading is one of the most effective methods to increase the usage of Renewable Energy (RE) resources in the distribution network and reduce losses by eliminating long transmission and distribution lines. This research aims to enhance the efficiency of P2P energy trading by examining the suitability of four distinct double auction mechanisms: Average, McAfee, Trade Reduction and Vickrey-Clarke-Groves (VCG). We conducted a systematic evaluation of these mechanisms across various microgrid (MG) types. The study algorithm integrates user preferences, bidding strategies and time-of-use tariffs, allowing participants to indicate their willingness to pay for different energy qualities and specific time periods. Notably, both the Average and VCG mechanisms emerged as the most effective across a majority of MG setups. Specifically, the average mechanism was found to be optimal for a consumer-centric MG, while the VCG mechanism was predominantly advantageous during non-peak hours trading. However, it was observed that P2P energy trading from MG to MG was inefficient due to the lesser number of peers. In conclusion, this work offers a comprehensive solution that adeptly identifies and recommends the most fitting auction mechanisms for diverse MG configurations and usage timings, paving the way for more efficient P2P energy trading.

11.
Front Microbiol ; 14: 1192763, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37808284

RESUMEN

Background: Bovine respiratory disease (BRD) is a significant health problem in beef cattle production, resulting in considerable economic losses due to mortalities, cost of treatment, and reduced feed efficiency. The onset of BRD is multifactorial, with numerous stressors being implicated, including transportation from farms to feedlots. In relation to animal welfare, regulations or practices may require mandatory rest times during transportation. Despite this, there is limited information on how transportation and rest stops affect the respiratory microbiota. Results: This study evaluated the effect of cattle source (ranch-direct or auction market-derived) and rest stop duration (0 or 8 h of rest) on the upper respiratory tract microbiota and its relationship to stress response indicators (blood cortisol and haptoglobin) of recently weaned cattle transported for 36 h. The community structure of bacteria was altered by feedlot placement. When cattle were off-loaded for a rest, several key bacterial genera associated with BRD (Mannheimia, Histophilus, Pasteurella) were increased for most sampling times after feedlot placement for the ranch-direct cattle group, compared to animals given no rest stop. Similarly, more sampling time points had elevated levels of BRD-associated genera when auction market cattle were compared to ranch-direct. When evaluated across time and treatments several genera including Mannheimia, Moraxella, Streptococcus and Corynebacterium were positively correlated with blood cortisol concentrations. Conclusion: This is the first study to assess the effect of rest during transportation and cattle source on the respiratory microbiota in weaned beef calves. The results suggest that rest stops and auction market placement may be risk factors for BRD, based solely on increased abundance of BRD-associated genera in the upper respiratory tract. However, it was not possible to link these microbiota to disease outcome, due to low incidence of BRD in the study populations. Larger scale studies are needed to further define how transportation variables impact cattle health.

12.
Environ Sci Pollut Res Int ; 30(42): 96424-96440, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37567993

RESUMEN

As the problems of "valuing compliance over trading" and quota over-allocation seriously affect the effectiveness of China's national carbon emission trading (CET) market, the quota auction mechanism will be introduced timely to solve these problems. Since implementing the quota auction means reduced free quotas, regulated enterprises are more motivated to pursue low-carbon technology innovation (L-CTI). On these grounds, by establishing a system dynamics model of the national CET market and designing seven scenarios for simulation analysis, this paper investigates the impact of quota auction and L-CTI on the emission reduction effectiveness and cost effectiveness of the national CET market. The results indicate that for the national CET market, introducing quota auction is conducive to decreasing the CET price and improving its liquidity and emission reduction effectiveness, which is one of the quota allocation mechanisms to improve the CET market effectiveness at present. However, the quota auction will increase the abatement cost and reduce the cost effectiveness. Therefore, to improve the institutional performance of China's CET system, it is necessary to conduct L-CTI to alleviate the increasing abatement cost caused by quota auction, and thus improve the emission reduction effectiveness and cost effectiveness of the national CET market.


Asunto(s)
Carbono , Análisis de Sistemas , Carbono/análisis , Tecnología , China
13.
Sensors (Basel) ; 23(14)2023 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-37514774

RESUMEN

This study presents an architectural framework for the blockchain-based usage-based insurance (UBI) policy auction mechanism in the internet of vehicles (IoV) applications. The main objective of this study is to analyze and design the specific blockchain architecture and management considerations for the UBI environment. An auction mechanism is developed for the UBI blockchain platform to enhance consumer trust. The study identifies correlations between driving behaviors and associated risks to determine a driver's score. A decentralized bidding algorithm is proposed and implemented on a blockchain platform using elliptic curve cryptography and first-price sealed-bid auctions. Additionally, the model incorporates intelligent contract functionality to prevent unauthorized modifications and ensure that insurance prices align with the prevailing market value. An experimental study evaluates the system's efficacy by expanding the participant pool in the bidding process to identify the winning bidder and is investigated under scenarios where varying numbers of insurance companies submit bids. The experimental results demonstrate that as the number of insurance companies increases exponentially, the temporal overhead incurred by the system exhibits only marginal growth. Moreover, the allocation of bids is accomplished within a significantly abbreviated timeframe. These findings provide evidence that supports the efficiency of the proposed algorithm.

14.
Exp Econ ; : 1-27, 2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-37363161

RESUMEN

This paper is concerned with multi-object, multi-unit auctions with a budget constrained auctioneer who has noisy value estimates for each object. We propose a new allocation mechanism, the endogenous reference price auction, with two key features. First, bids are normalized across objects using "reference prices." Second, reference prices are set endogenously using information extracted from the bids submitted. We report on an experiment showing that a simple endogenous process mitigates value inaccuracies and improves three performance measures: the seller's profit, allocative efficiency and total surplus. These results have important implications for large auctions used in practice. Supplementary Information: The online version contains supplementary material available at 10.1007/s10683-022-09783-6.

15.
Comput Commun ; 206: 85-100, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37197296

RESUMEN

The recruitment of trustworthy and high-quality workers is an important research issue for MCS. Previous studies either assume that the qualities of workers are known in advance, or assume that the platform knows the qualities of workers once it receives their collected data. In reality, to reduce costs and thus maximize revenue, many strategic workers do not perform their sensing tasks honestly and report fake data to the platform, which is called False data attacks. And it is very hard for the platform to evaluate the authenticity of the received data In this paper, an incentive mechanism named Semi-supervision based Combinatorial Multi-Armed Bandit reverse Auction (SCMABA) is proposed to solve the recruitment problem of multiple unknown and strategic workers in MCS. First, we model the worker recruitment as a multi-armed bandit reverse auction problem and design an UCB-based algorithm to separate the exploration and exploitation, regarding the Sensing Rates (SRs) of recruited workers as the gain of the bandit Next, a Semi-supervised Sensing Rate Learning (SSRL) approach is proposed to quickly and accurately obtain the workers' SRs, which consists of two phases, supervision and self-supervision. Last, SCMABA is designed organically combining the SRs acquisition mechanism with multi-armed bandit reverse auction, where supervised SR learning is used in the exploration, and the self-supervised one is used in the exploitation. We theoretically prove that our SCMABA achieves truthfulness and individual rationality and exhibits outstanding performances of the SCMABA mechanism through in-depth simulations of real-world data traces.

16.
Front Vet Sci ; 10: 1137078, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37008349

RESUMEN

Introduction: Stressors predisposing to bovine respiratory disease (BRD) upon arrival in the feedlot, include the ranch to feedlot transition and mixing cattle from multiple sources. Preconditioning (PC) reduces multiple stressors, but commingling PC and auction-derived (AD) calves in a feedlot may increase BRD risk. Our objective was to evaluate PC calf performance over the first 40 days in the feedlot and determine impacts of commingling with varying proportions of AD calves (25, 50, and 75%). Methods: Calves were either preconditioned at one ranch (n = 250) or mixed-source and bought from a local auction (n = 250). At arrival, calves were assigned into 1 of 5 pens: 100 PC, 75 PC, 50 PC, 25 PC, and 0 PC, reflecting the percentage of PC calves in a 100-head pen. Results: Over 40 days, morbidity in pen 100 PC was lower compared to 0 PC (24 vs. 50%, P < 0.001) and varied in commingled pens, being highest (63%) in 25 PC and least (21%) in 50 PC (P < 0.05). There were 3 AD deaths in 0 PC and 2 deaths in 25 PC. The AD calves in 0 PC were 3 times more likely to get BRD than PC calves in 100 PC; however, AD calves gained 0.49 kg/d more than PC calves (P < 0.0001). Ignoring pen placement, AD calves were 2.76 times more likely to get BRD but gained 0.27 kg/d more than PC calves (P < 0.0001). Commingling did not affect morbidity of PC (P = 0.5) or AD calves (P = 0.96), implying commingling did not affect health. Calves in 25 PC were 3.39 times more likely to get BRD than those in the 100 PC (P < 0.001). Furthermore, 25 PC calves gained the most (1.08 kg/d), followed by 50 PC (0.62 kg/d) and 75 PC (0.61 kg/d), compared to 100 PC (P < 0.05). Calf weight at arrival modified ADG (P < 0.05). Discussion: In conclusion, PC calves had lower morbidity over the first 40 days, irrespective of commingling. With larger variations in arrival weight, there was no advantage of PC for ADG in the first 40 days. The unknown weaning strategies and comparable arrival weights of AD calves may have contributed to greater ADG in AD calves.

17.
J Agromedicine ; 28(3): 401-414, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36789737

RESUMEN

Social isolation within agricultural communities is prevalent within the United Kingdom (UK). Along with other social and economic determinants, social isolation is considered to be a contributing factor towards the high rates of mental health issues experienced among people working in agriculture. The livestock auction mart is one of the remaining spaces upon which many livestock farmers rely for consistent social interaction and to experience community, both determinants proven to improve physical and mental health. However, the importance of the social contribution of livestock auction marts to farmer wellbeing appears rarely in associated literature. The aims of this study, therefore, were i) to determine levels of isolation experienced by livestock farmers who attend auction marts and ii) to identify the role of the mart as a system of social support, with an emphasis on the informal support system attendees provide for one another. Findings from 90 qualitative interviews demonstrate that the auction mart is an important social site where occupational community and identity can be produced and reproduced for all attending stakeholders, positively impacting upon mental health and wellbeing. The strength of the occupational community among livestock farmers should be considered as a key element among a basket of options approach in the development of support interventions, and as a pathway to negotiating barriers to both help-seeking behaviors and reaching the hard-to-reach.


Asunto(s)
Agricultores , Salud Mental , Animales , Humanos , Agricultores/psicología , Ganado , Agricultura , Reino Unido
18.
bioRxiv ; 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36711724

RESUMEN

The dopamine reward prediction error signal is known to be subjective but has so far only been related to explicit external stimuli and rewards. However, personal choices are based on private internal values of the rewards at stake. Without indications of an agent's private internal value, we do not know whether dopamine neurons, or any reward neurons, encode the internal value. The well-established Becker-DeGroot-Marschak (BDM) auction-like mechanism allows participants to place bids for freely stating their private internal value for a good. BDM bids are known to reflect the agent's true internal valuation, as inaccurate bidding results in suboptimal reward ('incentive compatibility'). In our experiment rhesus monkeys placed BDM bids for juice rewards without specific external constraints. Their bids for physically identical rewards varied trial by trial and increased overall for larger rewards. Responses of midbrain dopamine neurons followed the trial-by-trial variation of bids despite constant, explicitly predicted reward amounts; correspondingly, the dopamine responses were similar when the animal placed similar bids for different reward amounts. Support Vector Regression demonstrated accurate prediction of the animal's bids by as few as twenty dopamine neurons, demonstrating the validity of the dopamine code for internal reward value. Thus, dopamine responses reflect the instantaneous internal subjective reward value rather than the value imposed by external stimuli.

19.
J Dairy Sci ; 106(1): 132-150, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36333136

RESUMEN

Concerns about antibiotic resistant infections in the United States have called for reduction of antibiotic use in livestock, including dairy cattle. Although effective in curbing antibiotic use, universal organic dairy farming would be impractical and unattainable due to its high land and premium demands. The US Department of Agriculture's organic certification, which completely eliminates antibiotic use in milk production, also raises animal welfare concerns, as it could discourage the use of antibiotics even to treat indicated diseases. Therefore, a proposed alternative for US consumers is a label indicating the responsible antibiotic use (RAU) - not complete elimination - that would minimize antibiotics more than conventional (unlabeled) milk and maximize animal welfare more than organic milk. Our goal was to determine consumers' (1) self-reported preference and (2) willingness to pay for this hypothetical RAU label of milk relative to existing substitutes in organic and unlabeled fluid milk. We conducted (1) a nationally representative survey of US adults and (2) a randomized non-hypothetical experimental Becker-Degroot-Marschak auction with real money and real milk. Although almost half of the survey participants (48.5%) responded that they would buy a RAU-labeled milk, consumers in the experimental auction refused to pay a significant premium for the milk compared with unlabeled milk (mean willingness to pay (95% confidence interval) per half-gallon: $1.92 ($1.65-$2.19) for RAU-labeled milk versus $1.86 ($1.58-$2.13) for unlabeled milk). These results suggest that consumers' survey-identified preferences for RAU-labeled milk could reflect either social desirability bias or a genuine preference for which, however, consumers simply will not pay a significant premium. The study provides preliminary data for future exploration of marketability of the proposed RAU label in the United States and demonstrates the benefits of using complementary survey and experimental auction approaches to understand the potential market for a new dairy product.


Asunto(s)
Comportamiento del Consumidor , Leche , Bovinos , Animales , Estados Unidos , Antibacterianos , Bienestar del Animal , Encuestas y Cuestionarios
20.
Environ Sci Pollut Res Int ; 30(12): 34518-34535, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36515871

RESUMEN

Due to the intensified environmental protection consciousness of enterprises and consumers, the green winner determination (GWD) considering environmental performance becomes very important for the 4PL transportation service procurement. In this paper, a new GWD method is studied, which considers different types of attributes including those related to environmental performance and the consensus reaching process (CRP). To characterize multiple types of attributes, linguistic terms, interval numbers, and crisp numbers are combined. To achieve an acceptable consensus level among linguistic evaluations given by different experts, a minimum adjustment consensus model is constructed. And on this basis, an interactive CRP is proposed. Integrating the heterogeneous information addressing process and the CRP, a HC-VIKOR method is developed to promote the 4PL's operational efficiency and service quality. Further, a numerical example is designed to demonstrate the effectiveness of the proposed method. Sensitivity analysis reveals that both the acceptable consensus threshold and the weight of group utility have a significant influence on the winner determination result. Comparison analysis shows that the proposed method outperforms the existing methods. Our study not only extends the traditional winner determination but also provides decision support for the 4PL to provide transportation services efficiently.


Asunto(s)
Conservación de los Recursos Naturales , Transportes , Consenso , Lingüística
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