Leading biologists and philosophers of biology discuss the basic theories and concepts of biology and their connections with ethics, economics, and psychology, providing a remarkably unified report on the “state of the art” in the philosophy of biology.

BackgroundThe proper and ethical inclusion of PWLHIV and their young children in research is paramount to ensure valid evidence is generated to optimize treatment and care. Little empirical data exists to inform ethical considerations deemed most critical to these populations. Our study aimed to systematically review the empiric literature regarding ethical considerations for research participation of PWLHIV and their young children.MethodsWe conducted this systematic review in partnership with a medical librarian. A search strategy was designed and performed within the following (...) electronic databases: Ovid MEDLINE, Embase and CINAHL. We screened titles and abstracts using the following inclusion criteria: (1) a study population of PWLHIV or children under 5 years of age; and (2) collection of qualitative or quantitative data regarding ethics of research participation. Excluded were reviews, commentaries, policy statements, clinical care-related ethics concerns, abstracts, case studies, or studies unrelated to HIV research. Studies were appraised for quality, data were extracted, and studies were qualitatively analyzed using a principle-based ethical framework within the Belmont Report.ResultsOf the 7470 titles identified, 538 full-text articles were reviewed for eligibility and only three articles met full criteria for inclusion within this review. While we allowed for inclusion of studies involving young children born to mothers with HIV, only articles focused on PWLHIV were identified. Within the results of these studies, four themes emerged: (1) adequacy of informed consent; (2) consideration of paternal involvement; (3) balancing risks; and (4) access to research and treatment. A strength of this review is that it included perspectives of international research investigators, community leaders, and male partners. However, only two studies collected empiric data from PWLHIV regarding their experiences participating in researchConclusionResearchers and funding agencies should be aware of these considerations and appreciate the value of and critical need for formative research to ensure clinical trials involving PWLHIV promote ethical, well-informed research participation and, ultimately, improve care outcomes. More research is needed to create a comprehensive ethical framework for researchers when conducting studies with PWLHIV. (shrink)

As crucial interface organs gut and skin have much in common. Therefore it is unsurprising that several gut pathologies have skin co‐morbidities. Nevertheless, the reason for this remains ill explored, and neither mainstream gastroenterology nor dermatology research have systematically investigated the ‘gut‐skin axis'. Here, in reviewing the field, we propose several mechanistic levels on which gut and skin may interact under physiological and pathological circumstances. We focus on the gut microbiota, with its huge metabolic capacity, and the role of dietary (...) components as potential principle actors along the gut‐skin axis. We suggest that metabolites from either the diet or the microbiota are skin accessible. After defining open key questions around the nature of these metabolites, how they are sensed, and which cutaneous changes they can induce, we propose that understanding of these pathways will lead to novel therapeutic strategies based on targeting one organ to improve the health of the other. (shrink)

RationaleSurrogates of critically ill patients often have inaccurate expectations about prognosis. Yet there is little research on how intensive care unit clinicians should discuss prognosis, and existing expert opinion-based recommendations give only general guidance that has not been validated with surrogate decision makers.ObjectiveTo determine the perspectives of key stakeholders regarding how prognostic information should be conveyed in critical illness.MethodsThis was a multicenter study at three academic medical centers in California, Pennsylvania, and Washington. One hundred eighteen key stakeholders completed in-depth semistructured (...) interviews. Participants included 47 surrogates of adult patients with acute respiratory distress syndrome; 45 clinicians working in study ICUs, including physicians, nurses, social workers, and spiritual care providers; and 26 experts in health communication, decision science, ethics, family-centered care, geriatrics, healthcare disparities, palliative care, psychology, psychiatry, and critical care.Measurements and main resultsThere was broad support among surrogates for existing expert recommendations, including truthful prognostic disclosure, emotional support, tailoring the disclosure strategy to each family's needs, and checking for understanding. In addition, stakeholders offered suggestions that add specificity to existing recommendations, including: In addition to conveying prognostic estimates, clinicians should help families "see the prognosis for themselves" by showing families radiographic images and explaining the clinical significance of physical manifestations of severe disease at the bedside. Many physicians did not support using numeric estimates to convey prognosis to families, whereas many surrogates, clinicians from other disciplines, and experts believed numbers could be helpful. Clinicians should conceptualize prognostic communication as an iterative process that begins with a preliminary mention of the possibility of death early in the ICU stay and becomes more detailed as the clinical situation develops. Although prognostic information should be initially disclosed by physicians, other members of the multidisciplinary team-nurses, social workers, and spiritual care providers-should be given explicit role responsibilities to reinforce physicians' prognostications and help families process a poor prognosis emotionally.ConclusionsFamily members, clinicians, and experts identified specific communication behaviors that clinicians should use to discuss prognosis in the critical care setting. These findings extend existing opinion-based recommendations and should guide interventions to improve communication about prognosis in ICUs. (shrink)

In his long and illuminating paper [1] Joe Barback defined and showed to be non-vacuous a class of infinite regressive isols he has termed “complete y torre” isols. These particular isols a enjoy a property that Barback has since labelled combinatoriality. In [2], he provides a list of properties characterizing the combinatoria isols. In Section 2 of our paper, we extend this list of characterizations to include the fact that an infinite regressive isol X is combinatorial if and only if (...) its associated Dekker semiring D satisfies all those Π2 sentences of the anguage LN for isol theory that are true in the set ω of natural numbers. of the various function and relation symbols of LN via the “lifting ” to D of their Σ1 definitions in ω coincide with their interpretations via isolic extension.) We also note in Section 2 that Π2-correctness, for semirings D, cannot be improved to Π 3-correctness, no matter how many additional properties we succeed in attaching to a combinatoria isol; there is a fixed equation image sentence that blocks such extension. In Section 3, we provide a proof of the existence of combinatorial isols that does not involve verification of the extremely strong properties that characterize Barback's CT isols. (shrink)

Let Λ denote the semiring of isols. We characterize existential completeness for Nerode subsemirings of Λ, by means of a purely isol-theoretic “Σ1 separation property”. Our characterization is purely isol-theoretic in that it is formulated entirely in terms of the extensions to Λ of the Σ1 subsets of the natural numbers. Advantage is taken of a special kind of isol first conjectured to exist by Ellentuck and first proven to exist by Barback . In addition, we strengthen the negative part (...) of [13] by showing that existential completeness is not secured, for a given Nerode semiring, by either a certain “functional closure” property for the extensions of partial recursive functions or the property of “pulling in” some portion of each partial recursive fiber; these latter results are perhaps a little surprising. (shrink)

We construct a recursive ultrapower F/U such that F/U is a tame 1-model in the sense of [6, §3] and FU is existentially incomplete in the models of II2 arithmetic. This enables us to answer in the negative a question about closure with respect to recursive fibers of certain special semirings Γ of isols termed tame models by Barback. Erik Ellentuck had conjuctured that all such semirings enjoy the closure property in question. Our result is that while many do, some (...) do not. (shrink)

Several problems that pertain to certain arithmetically well-behaved countable subsemirings of Λ, the semiring of isols, are discussed. This is relevant to the present volume memorializing the late John Myhill, in that Myhill was an early co-developer of the theory of Λ.

Given a Δ1 ultrapower ℱ/[MATHEMATICAL SCRIPT CAPITAL U], let ℒU denote the set of all Π2-correct substructures of ℱ/[MATHEMATICAL SCRIPT CAPITAL U]; i.e., ℒU is the collection of all those subsets of |ℱ/[MATHEMATICAL SCRIPT CAPITAL U]| that are closed under computable functions. Defining in the obvious way the lattice ℒ) with domain ℒU, we obtain some preliminary results about lattice embeddings into – or realization as – an ℒ. The basis for these results, as far as we take the matter, (...) consists of the well-known class of minimal ℱ/[MATHEMATICAL SCRIPT CAPITAL U]'s, which function as atoms, and the class of minimalfree ℱ/[MATHEMATICAL SCRIPT CAPITAL U]'s, to whose nonemptiness a substantial section of the paper is devoted. It is shown that an infinite, convergent monotone sequence together with its limit point is embeddable in an ℒ, and that the initial segment lattices {0, 1,…, n } are not just embeddable in , but in fact realizable as, lattices ℒ. Finally, the diamond is embeddable; and if it is not realizable, then either the 1 - 3 - 1 lattice or the pentagon is at least embeddable. (shrink)

Hirschfeld and Wheeler proved in 1975 that ∑1 ultrapowers (= “simple models”) are rigid; i.e., they admit no non-trivial automorphisms. We later noted, essentially mimicking their technique, that the same is true of Δ1 ultrapowers (= “Nerode semirings”), a class of models of Π2 Arithmetic that overlaps, but is mutually non-inclusive with, the class of Σ1 ultrapowers. Hirschfeld and Wheeler left as open the question whether some Σ1 ultrapowers might admit proper isomorphic self-injections. We do not answer that question; but (...) we do answer the corresponding question, in the negative, for the Δ1 case. (shrink)