We present a general derivation of the Duffin-Kemmer-Petiau (D.K.P) equation on the relativistic phase space proposed by Bohm and Hiley. We consider geometric algebras and the idea of algebraic spinors due to Riesz and Cartan. The generators βμ (p) of the D.K.P algebras are constructed in the standard fashion used to construct Clifford algebras out of bilinear forms. Free D.K.P particles and D.K.P particles in a prescribed external electromagnetic field are analized and general Liouville type equations for these cases are (...) obtained. Choosing particular values for the label p we classify the different types of the D.K.P Liouville operators. (shrink)

This study explored drug users’ attitudes toward and understanding of randomized controlled trials testing addiction therapies. A video portraying a fictional consent conference for a randomized controlled trial with placebo arm was shown to poor male and female drug users of diverse ethnic status and sexual orientation. The video stimulated focus group discussion in which participants’ comments often reflected “experimental realism”—a realistic view of the trial—and adequate understanding of the uncertain efficacy of the treatment being tested, as well as the (...) concepts of randomization and placebo control. However, participants’ comprehension of the nature of placebos was compromised by the widespread view that placebos are a way of testing a subject’s willpower and personal control over his or her addiction. Comments also showed a mistrust of the video investigator’s integrity and competence and signs of therapeutic misconception and misestimation. The study’s findings underscore the importance of tailoring informed consent encounters to the personal and sociohistorical context of participants’ lived experiences. (shrink)

Dispositions are essential to our understanding of the world. Dispositions: A Debate is an extended dialogue between three distinguished philosophers - D.M. Armstrong, C.B. Martin and U.T. Place - on the many problems associated with dispositions, which reveals their own distinctive accounts of the nature of dispositions. These are then linked to other issues such as the nature of mind, matter, universals, existence, laws of nature and causation.

We apply the Galilean covariant formulation of quantum dynamics to derive the phase-space representation of the Pauli–Schrödinger equation for the density matrix of spin-1/2 particles in the presence of an electromagnetic field. The Liouville operator for the particle with spin follows from using the Wigner–Moyal transformation and a suitable Clifford algebra constructed on the phase space of a (4 + 1)-dimensional space–time with Galilean geometry. Connections with the algebraic formalism of thermofield dynamics are also investigated.

Atualmente, biotecnologias são empregadas na forma de protocolos a fim de sincronizar o crescimento folicular e a ovulação, bem como permitir que vacas atuem como receptoras de embriões visando melhorar o potencial genético do rebanho. O objetivo desse estudo foi avaliar o efeito da utilização de implantes intravaginais de progesterona de 1º, 2º e 3º uso no protocolo de transferência de embriões em tempo fixo (TETF) sobre a taxa de prenhez em receptoras girolandas. O experimento ocorreu em uma fazenda localizada (...) no município de São Sebastião do Maranhão (MG). Foram utilizadas 74 vacas submetidas aos seguintes protocolos: No dia 0 (D0) administrou-se 2 ml de 17β-Estradiol e progesterona e foi colocado o implante intravaginal de progesterona. Estes implantes foram colocados de forma aleatória, sendo de 1° uso (grupo 1; n=15), 2° (grupo 2; n=24) ou 3° (grupo 3; n=35).No D8, os implantes foram retirados e administrou-se 2 ml PGF2α; 1,5 ml de eCG e 1 ml de 17β-Estradiol e progesterona. A inovulação dos embriões in vitroo correu no D (16) para todas as vacas que apresentaram um corpo lúteo. As variáveis qualitativas (prenhe ou não prenhe) foram comparadas em tabelas de contingência e analisadas pelo teste de qui-quadrado a 5% de probabilidade. Neste estudo não houve diferença estatística entre os grupos protocolados em relação ao aproveitamento como receptoras: 1º uso (53,3%), 2º (79,2%) e 3º (68,65). Ademais, observou-se uma taxa de prenhez entre os grupos de 37,5% para o 1º uso, 42,1% para o 2º e 33,3% para o 3º (P>0,05). Dentre as vantagens ao reaproveitamento dos implantes multiusos destaca-se a redução dos custos dos protocolos hormonais, já que a progesterona é o hormônio mais oneroso, desta forma, a maximização do uso reduz o valor final do protocolo sem prejuízos a taxa de prenhez. (shrink)

'Why did the window break when it was hit by the stone? Because the window is brittle and the stone is hard; hardness and brittleness are powers, dispositional properties or dispositions.' Dispositions are essential to our understanding of the world. This book is a record of the debate on the nature of dispositions between three distinguished philosophers - D. M. Armstrong, C. B. Martin and U. T. Place - who have been thinking about dispositions all their working lives. Their distinctive (...) accounts cover many of the issues surrounding dispositions such as the nature of mind, matter, universals, existence, laws of nature and causation. Dispositions illuminates this central topic in analytic philosophy and at the same time highlights deeper concerns of metaphysics. (shrink)

Smart farming has largely been driven by productivity and efficiency aims, but there is an increasing awareness of potential socio-ethical challenges. The responsible research and innovation approach aims to address such challenges but has had limited application in smart farming contexts. Using smart dairying research and development in New Zealand as a case study, we examine the extent to which principles of RRI have been applied in NZ smart dairying development and assess the broader lessons for RRI application in smart (...) farming. We draw on insights from: a review of research on dairy technology use in NZ; interviews with smart dairying stakeholders; and the application of an analytical framework based on RRI dimensions. We conclude that smart dairying R&D and innovation activities have focused on technology development and on-farm use without considering socio-ethical implications and have excluded certain actors such as citizens and consumers. This indicates that readiness to enact RRI in this context is not yet optimal, and future RRI efforts require leadership by government or dairy sector organisations to fully embed RRI principles in the guidelines for large R&D project design. More broadly, enacting RRI in smart farming requires initial identification of RRI readiness in a given sector or country and devising a roadmap and coherent project portfolio to support capacity building for enacting RRI. Additionally, methods for operationalising RRI must be adapted to the context of the national or sectoral innovation system in which smart farming is being developed. (shrink)

Argumentation as the public exchange of reasons is widely thought to enhance deliberative interactions that generate and justify reasonable public policies. Adopting an argumentation-theoretic perspective, we survey the norms that should govern public argumentation and address some of the complexities that scholarly treatments have identified. Our focus is on norms associated with the ideals of correctness and participation as sources of a politically legitimate deliberative outcome. In principle, both ideals are mutually coherent. If the information needed for a correct deliberative (...) outcome is distributed among agents, then maximising participation increases information diversity. But both ideals can also be in tension. If participants lack competence or are prone to biases, a correct deliberative outcome requires limiting participation. The central question for public argumentation, therefore, is how to strike a balance between both ideals. Rather than advocating a preferred normative framework, our main purpose is to illustrate the complexity of this theme. (shrink)

In this article, we present results from a literature review of intrinsic, instrumental, and relational values of nature conducted for the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, as part of the Methodological Assessment of the Diverse Values and Valuations of Nature. We identify the most frequently recurring meanings in the heterogeneous use of different value types and their association with worldviews and other key concepts. From frequent uses, we determine a core meaning for each value type, which is (...) sufficiently inclusive to serve as an umbrella over different understandings in the literature and specific enough to help highlight its difference from the other types of values. Finally, we discuss convergences, overlapping areas, and fuzzy boundaries between different value types to facilitate dialogue, reduce misunderstandings, and improve the methods for valuation of nature's contributions to people, including ecosystem services, to inform policy and direct future research. © 2023 The Author(s). Published by Oxford University Press on behalf of the American Institute of Biological Sciences. (shrink)