Antioxidative Peptides Derived from Enzyme Hydrolysis of Bone Collagen after Microwave Assisted Acid Pre-Treatment and Nitrogen Protection

This study focused on the preparation method of antioxidant peptides by enzymatic hydrolysis of bone collagen after microwave assisted acid pre-treatment and nitrogen protection. Phosphoric acid showed the highest ability of hydrolysis among the four other acids tested (hydrochloric acid, sulfuric acid and/or citric acid). The highest degree of hydrolysis (DH) was 9.5% using 4 mol/L phosphoric acid with a ratio of 1:6 under a microwave intensity of 510 W for 240 s. Neutral proteinase gave higher DH among the four protease tested (Acid protease, neutral protease, Alcalase and papain), with an optimum condition of: (1) ratio of enzyme and substrate, 4760 U/g; (2) concentration of substrate, 4%; (3) reaction temperature, 55 °C and (4) pH 7.0. At 4 h, DH increased significantly (P < 0.01) under nitrogen protection compared with normal microwave assisted acid pre-treatment hydrolysis conditions. The antioxidant ability of the hydrolysate increased and reached its maximum value at 3 h; however DH decreased dramatically after 3 h. Microwave assisted acid pre-treatment and nitrogen protection could be a quick preparatory method for hydrolyzing bone collagen

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

An agent architecture for open system specifications

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Interaction patterns and observable commitments in a multi-agent trading scenario

We propose a formal semantics for the protocol diagrams (interaction patterns) of AUML (Agent Unified Modelling Language). We connect this proposal with a general framework for defining the semantics of ACLs (Agent Communication Languages). We then show that protocol diagrams should be parameterised with observable commitments: additional specification of the expected outcomes and normative positions resulting from the use of the protocol. A complete axiomatisation of a contract-net protocol is given, and animated to show how the agents comply with expected replies and respecting the norms. We conclude that this approach to ‘socialising ’ interaction between agents is important for developing open agent systems and potentially useful in standardisation. 1

Quarto Workshop Internazionale \u201cEngineering Societies in the Agents World\u201d (ESAW 2003)

Rapporto sul Quarto Workshop Internazionale \u201cEngineering Societies in the Agents World\u201d (ESAW 2003

Norm-aware agents for ad hoc networks: A position paper

Abstract. A norm-governed, agent-based approach is proposed as a key technology for operating Ad Hoc networks, both as the logical platform for ubiquitous computing applications and as the physical platform for ubiquitous computing environments. Of the many issues raised by such a proposal, three are: what kind of cognitive capability the agents require, what kind of social and regulatory organisation is expected; and what kind of coordination mechanism is appropriate. This position statement explores the requirements of agents with respect to these issues: the architecture for ‘cognitive ’ software agents, the communication protocols for coordination, and the management languages for social regulation. Through this review, we aim to open up important theoretical and practical issues in the design and construction of intelligent software agents as components of Ad Hoc networks for/in ubiquitous computing.

Voting in online deliberative assemblies

Voting is an essential element of mechanism design for multiagent systems, and decision support for CSCW tools implementing online deliberative assemblies. Much attention has been given both to designing the process so that it is resistant to manipulation by strategic voting, and so that an automated system can follow rules of order as developed for the conduct of formal meetings. In this paper, we formalise a general voting protocol trying to take into account a right to cast a vote, and an entitlement that the vote cast is counted in the correct way. We discuss the design and development of a system for online deliberative assemblies, that incorporates this protocol as part of a suite of protocols which collectively implement rules of order. We conclude with some comments on the voting protocol as it relates to the 2004 ACM Statement on E-Voting. 1

Formalization of a voting protocol for virtual organizations

A voting protocol for decision-making in virtual organizations is presented. In an agent-based virtual organization the functions of formation, management and dissolution of the organization are passed to software processes. Each phase in this life-cycle requires decision making: an ostensibly fair way for independent agents to make decisions is to take a vote. Accordingly, this paper formalizes a protocol for voting. The emphasis is on characterising the powers, permissions, obligations and even sanctions of the voters, using a norm-governed approach to agent societies. The specification language is the Event Calculus, and its animation is informative with respect to a full implementation. It is wellknown that various types of ad hoc alliance of autonomous entities require voting procedures, and a normative specification of the interactions is therefore beneficial for many aspects of self-organization and self-management