End-to-End Formal Verification of Ethereum 2.0 Deposit Smart Contract

We report our experience in the formal verification of the deposit smart contract, whose correctness is critical for the security of Ethereum 2.0, a new Proof-of-Stake protocol for the Ethereum blockchain. The deposit contract implements an incremental Merkle tree algorithm whose correctness is highly nontrivial, and had not been proved before. We have verified the correctness of the compiled bytecode of the deposit contract to avoid the need to trust the underlying compiler. We found several critical issues of the deposit contract during the verification process, some of which were due to subtle hidden bugs of the compiler.Ope

Consumer preferences for wild game cured meat label : do attitudes towards animal welfare matter?

Even though the European Union has imposed a mandatory labeling system for conventional meats, there is no mandatory labelling scheme for the so called \u201cminor meats\u201d- such as hunted wild game meat (HWGM). Thus, some European countries have implemented voluntary labelling programs certificating the origin of wild game meat. This study uses a discrete choice experiment to (1) assess consumer preferences for processed meat products (including wild game meat bearing a HWGM label), and (2) investigate whether consumers\u2019 attitudes towards animal welfare affects their food choice behavior for alternative meat products. Data was collected through an online survey conducted in Italy and consumer preferences for HWGM was estimated through a latent class logit model. Overall, results suggest that, even though HWGM label does not exist yet on the Italian market, it is appealing to Italian consumers and it will likely be accepted by the majority of them. However, consumers who are particularly concerned about animal welfare issues and animal rights showed the lowest level of the interest in the hunted game meat product and thus the presence of the HWGM label does not provide any benefit to them. Our findings have important implications for the development of successful marketing strategies and policy intervention in the HWGM sector at a national and European level

FAUSTA: Scaling Dynamic Analysis with Traffic Generation at WhatsApp

We introduce Fausta, an algorithmic traffic gener-ation platform that enables analysis and testing at scale. Fausta has been deployed at Meta to analyze and test the WhatsApp plat-form infrastructure since September 2020, enabling WhatsApp developers to deploy reliable code changes to a code base of millions of lines of code, supporting over 2 billion users who rely on WhatsApp for their daily communications. Fausta covers expected and unexpected program behaviors in a privacy-safe controlled environment to support multiple use cases such as reliability testing, privacy analysis and performance regression detection. It currently supports three different algorithmic input generation strategies, each of which construct realistic backend server traffic that closely simulates production data, without replaying any real user data. Fausta has been deployed and closely integrated into the WhatsApp continuous integration process, catching bugs in development before they hit production. We report on the development and deployment of Fausta's reliability use case between September 2020 and August 2021. During this period it has found 1,876 unique reliability issues, with a fix rate of 74%, indicating a high degree of true positive fault revelation. We also report on the distribution of fault types revealed by Fausta, and the correlation between coverage and faults found. Overall, we do find evidence that higher coverage is correlated with fault revelation

The local value chain of hunted red deer meat : a scenario analysis based on a northern Italian case study

Although in recent decades, meat from hunted wild ungulates has shown interesting results in terms of market opportunities, the scientific literature is still lacking in economic studies concerning the estimation of the meat\u2019s value for involved stakeholders. We present an analysis of the evolution of price in the local red deer meat supply chain. This analysis has been conducted through a survey based on in-depth interviews with the stakeholders involved in an Italian local supply chain. Findings derived from this study describe a case study, however, they also represent the potential dynamics of the value of Italian game meat, highlighting that the development of a sustainable local supply chain of this product may represent an economic resource for involved stakeholders

National Brands versus Private Labels versus Niche Products: a graphical representation of consumers' perception

The more consumers\u2019 needs evolve, the more food market\u2019s stakeholders require information in order to make rational choices responding to consumption patterns\u2019 changes. In the present research the perception of well-established and niche food products is discussed. Five macro-categories of food have been considered: national brands, private labels, organic products, Protected Denomination of Origin products and local food. After decades of diversification strategies, we analyze similarities and dissimilarities between products on the basis of their perceived quality. The survey was conducted in Milan (Italy) between May and July 2014, collecting information about 360 adult consumers. Perception of products have been evaluated asking to interviewees to pick from a list of attributes, which ones they attach to each products. Data are elaborated through simple correspondence analysis, obtaining a perceptual map, which provides a graphical representation of links between attributes and products. Results suggest that consumer perceive national brands and private labels as similar and organic and local food distinctively differentiated by other products for sale in food market, but do not provide a completely reliable interpretation for PDO products. National brands and private labels remain the most convenient food, organic food are perceived as healthy, environmental-friendly, expensive and respectful of animal welfare, while local food is represented as traditional, fair and flavorful. No differences have been found controlling for gender, while consumer who are used to direct-sale recognize to PDO products the same characteristics of local food