This contribution is a gentle introduction to so-called dynamic epistemic logics, that can describe how agents change their knowledge and beliefs. We start with a concise introduction to epistemic logic, through the example of one, two and finally three players holding cards; and, mainly for the purpose of motivating the dynamics, we also very summarily introduce the concepts of general and common knowledge. We then pay ample attention to the logic of public announcements, wherein agents change their knowledge as the (...) result of public announcements. One crucial topic in that setting is that of unsuccessful updates: formulas that become false when announced. The Moore-sentences that were already extensively discussed at the conception of epistemic logic in Hintikka’s ‘Knowledge and Belief ’ (1962) give rise to such unsuccessful updates. After that, we present a few examples of more complex epistemic updates. (shrink)

This essay explores some concerns about the quality of informed consent in patients whose autonomy is diminished by fatal illness. It argues that patients with diminished autonomy cannot give free and voluntary consent, and that recruitment of such patients as subjects in human experimentation exploits their vulnerability in a morally objectionable way. Two options are given to overcome this objection: (i) recruit only those patients who desire to contribute to medical knowledge, rather than gain access to experimental treatment, or (ii) (...) provide prospective subjects the choice to participate in standard doubleblind study or receive the experimental treatment. Either option would guarantee that patients in desperate conditions are given a more meaningful choice and a richer freedom, and thus a higher quality of informed consent, than under standard randomized trials. (shrink)

There is currently a debate over whether cognitive architecture is classical or connectionist in nature. One finds the following three comparisons between classical architecture and connectionist architecture made in the pro-connectionist literature in this debate: (1) connectionist architecture is neurally plausible and classical architecture is not; (2) connectionist architecture is far better suited to model pattern recognition capacities than is classical architecture; and (3) connectionist architecture is far better suited to model the acquisition of pattern recognition capacities by learning than (...) is classical architecture. If true, (1)-(3) would yield a compelling case against the view that cognitive architecture is classical, and would offer some reason to think that cognitive architecture may be connectionist. We first present the case for (1)-(3) in the very words of connectionist enthusiasts. We then argue that the currently available evidence fails to support any of (1)-(3). (shrink)

Predation and escaping from predation through hiding are two fundamental phenomena in ecology. The most common approach to reducing the chance of predation is to use a refuge. Here, we consider a three species fishery model system with prey refuge induced by a Holling type-II functional response. These three species of fish populations are named prey, middle predator, and top predator. Harvesting is employed in most fishery models to achieve both ecological and commercial benefits. Research proves that non-linear harvesting (Michaelis–Menten (...) type) returns more realistic outcomes. So, we have combined the Michaelis–Menten type of harvesting efforts for all populations. Uniform boundedness conditions for the solutions of the model are discussed. The existence conditions for possible equilibrium points with stability are presented. We explain the dynamical behavior at each equilibrium point through bifurcation analysis. The persistent criteria of the system are examined. Bionomic equilibrium and optimal harvesting control using Pontryagin’s maximum principle are calculated. For validation of the model in the real world, we have implemented this in the freshwater ecosystem of Lake Victoria. Extraction of native fish species and ecological balances are the foremost solicitude of Lake Victoria. We may resolve this concern partially by implementing prey refuge, since it may sustain the ecology of Lake Victoria, and therefore also its economical importance. Lake Victoria is acclaimed worldwide for the trade of fishing. Also, it provides the largest employment in east-central Africa and is beneficial to fishing equipment manufacturers. So, the bionomic equilibrium and harvesting control have significant applications in the fisheries. All the analytical studies are verified by numerical simulations. We have plotted phase portraits, bifurcation diagrams, Lyapunov exponents to explore the dynamics of the proposed model. (shrink)

The United States District Court of Kansas, in Gudenkauf v. Stauffer, Znc., granted the defendants motion for summary judgment for the plaintiff's claims of pregnancy-related discrimination under the Americans with Disabilities Act and the Family and Medical Leave Act of 1993, but the court denied a similar motion for the plaintiff's claim under the Pregnancy Discrimination Act. The court found summary judgment to be appropriate for the ADA claim based on its finding that the plaintiff's pregnancy did not constitute an (...) impairment as required by the statute; as for the FMLA claim, it determined that the defendants failure to grant the plaintiff's leave request did not violate the statute. However, the court determined that summary judgment was inappropriate for the PDA claim because of material questions of fact about whether the defendant had acted with discriminatory intent.In considering the motions for summary judgment, the court accepted the following facts as incontrovertible. Plaintiff Michaela Gudenkauf worked for the defendant Stauffer, Inc. (shrink)

Background: Managing HIV treatment is a complex multi-dimensional task because of a combination of factors such as stigma and discrimination of some populations who frequently get infected with HIV. In addition, patient-provider encounters have become increasingly multicultural, making effective communication and provision of ethically sound care a challenge. Purpose: This article explores ethical issues that health service providers in the United States and Botswana encountered in their interaction with patients in HIV care. Research design: A descriptive qualitative design was used (...) to collect data from health service providers and patients using focused group discussions. This article is based on responses from health service providers only. Participants and context: This article is based on 11 focused group discussions with a total sample of 71 service providers in seven US sites and one Botswana site. Ethical considerations: Ethical review boards at all the study sites reviewed the study protocol and approved it. Ethical review boards of the study’s coordinating centers, Rutgers University and the University of California at San Francisco, also approved it. The study participants provided a written informed consent to participate. Findings: HIV service providers encountered ethical challenges in all the four Beauchamp and Childress’ biomedical ethics of respect for patients’ autonomy, beneficence, justice, and nonmaleficence. Discussion: The finding that HIV service providers encounter ethical challenges in their interaction with patients is supported by prior studies. The ethical challenges are particularly prominent in multicultural care and resource-constrained care environments. Conclusion: Provision of HIV care is fraught with ethical challenges that tend to pose different issues depending on a given care environment. It is important that strong partnerships are developed among key stakeholders in HIV care. In addition, health service providers need to be provided with resources so they can provide quality and ethically sound care. (shrink)

The central idea of this paper is that forming the black hole horizon is attended with the transition from the classical regime of evolution to the quantum one. We offer and justify the following criterion for discriminating between the classical and the quantum: creations and annihilations of particle-antiparticle pairs are impossible in the classical reality but possible in the quantum reality. In flat spacetime, we can switch from the classical picture of field propagation to the quantum picture by changing the (...) overall sign of the spacetime signature. To describe a self-gravitating object at the final stage of its classical evolution, we propose to use the Foldy–Wouthuysen representation of the Dirac equation in curved spacetimes, and the Gozzi classical path integral. In both approaches, maintaining the dynamics in the classical regime is controlled by supersymmetry. (shrink)