This dissertation is a defense of moderate invariantism, the traditional epistemological position combining the following three theses: invariantism, according to which the word ‘know’ expresses the same content in every context of use; intellectualism, according to which whether one knows a certain proposition does not depend on one’s practical interests; and antiskepticism, according to which we really do know much of what we ordinarily take ourselves to know. Moderate invariantism needs defending because of seemingly powerful arguments for contextualism, the view (...) that, like ‘I’ and ‘now’, ‘know’ expresses different contents in different contexts. It has been argued that only contextualism can properly reply to skeptical arguments, and that only contextualism can account for our tendency to go from judging that a knowledge claim is true to judging that it is false in response to shifts in the context of use. Moderate invariantist replies to these arguments have largely failed. I propose new replies on behalf of moderate invariantism, while critiquing earlier, less successful attempts. Chapter one is introductory. In chapters two and three, I examine contextualist replies to skeptical arguments arising from radical skeptical hypotheses (such as the possibility that one is a brain in a vat) and from considerations involving lotteries. I argue that if contextualism can adequately respond to these arguments, then there are equally effective replies available to the moderate invariantist. In the next two chapters, I examine Stewart Cohen’s “Airport Case,” which elicits intuitions about knowledge claims that supposedly only contextualism can accommodate. In chapter four, I argue that none of the invariantist replies to the case that depend on denying the intuitions succeed; in chapter five, I accept the intuitions, but argue that contextualism does not follow from them. Finally, in chapter six, I evaluate two interesting invariantist critiques of contextualism; according to the first, contextualism collapses into the radical position that every English expression is context-sensitive; according to the second, ‘know’ fails a test for context-sensitivity involving indirect speech reports. (shrink)

Endosymbiotic bacteria can directly manipulate their host's sex determination towards the production of female offspring.

Sex‐determining mechanisms appear to be very diverse in invertebrates. Haplodiploidy is a widespread mode of reproduction in insects: males are haploid and females are diploid. Several models have been proposed for the genetic mechanisms of sex determination in haplodiploid Hymenoptera. Although a one‐locus multi‐allele model is valid for several species, sex determination in other species cannot be explained by any of the existing models. Evidence for and predictions of two recently proposed models are discussed. Some genetic and molecular approaches are (...) proposed to study sex determination in Hymenoptera. (shrink)

The mechanisms by which sex is genetically determined are bewilderingly diverse and appear to change rapidly during evolution.(1) What makes the sex‐determining process so prone to perturbations? Two recent articles(2,3) explore theoretically the role of genetic conflict in sex determination evolution. Both studies use the idea that selection on sex‐determining genes may act differently in parents and in offspring and they suggest that the resulting conflict can drive changes in sex‐determining mechanisms. BioEssays 23:477–480, 2001. © 2001 John Wiley & Sons, (...) Inc. (shrink)

Now in its fifth edition, Good Reasoning Matters! is a practical guide to recognizing, evaluating, and constructing arguments. Combining straightforward instruction with abundant exercises and examples, this innovative introduction to argument schemes and rhetorical techniques will help students learn to think critically both within and beyond the classroom.

The Y chromosomes of most Drosophila species are necessary for male fertility but they are not involved in sex determination. They have many puzzling properties that resemble the effects caused by B chromosomes. Classical genetic and molecular studies reveal substantial affinities between Y and B chromosomes and suggest that the Y chromosomes of Drosophila are not degenerated homologues of the X chromosomes, but rather that their Y chromosomes evolved as specialized supernumeraries similar to classical B chromosomes.

On one hand, Chinese consumers are well known for conspicuous consumption and the adoption of luxury products and named brands. On the other hand, they also have a bad reputation for buying counterfeit products. Their simultaneous preferences for two contrasting types of product present a paradox that has not been addressed in the literature. This study attempts to present an explanation of this paradox by examining the effects of traditional Chinese cultural values and consumer values on consumers’ deontological judgment of (...) pirated CDs and the amount of social benefits they perceive they gain from them. We interviewed 300 Hong Kong Chinese consumers, and found that face consciousness increased materialism and risk aversion, thereby producing a favorable deontological judgment of pirated CDs. Face consciousness also has a direct effect on the amount of social benefits perceived in pirated CDs. Both favorable deontological judgment and perceived social benefits contributed to a strong intention to buy pirated CDs. The results are discussed in a cultural perspective. (shrink)

Carbon monoxide (CO), a product of organic oxidation processes, arises in vivo during cellular metabolism, most notably heme degradation. CO binds to the heme iron of most hemoproteins. Tissue hypoxia following hemoglobin saturation represents a principle cause of CO‐induced mortality in higher organisms, though cellular targets cannot be excluded. Despite extreme toxicity at high concentrations, low concentrations of CO can confer cytoprotection during ischemia/reperfusion or inflammation‐induced tissue injury. Likewise, heme oxygenase, an enzyme that produces CO, biliverdin and iron, as well (...) as a secondary increase in ferritin synthesis, from the oxidation of heme, can confer protection in vivo and in vitro. CO has been shown to affect several intracellular signaling pathways, including guanylate cyclase, which generates guanosine 3′:5′ cyclic monophosphate and the mitogen‐activated protein kinases (MAPK). Such pathways mediate, in part, the known vasoregulatory, anti‐inflammatory, anti‐apoptotic and anti‐proliferative effects of this gas. Exogenous CO delivered at low concentrations is showing therapeutic potential as an anti‐inflammatory agent and as such can modulate numerous pathophysiological states. This review will delve into the biological significance and medical applications of this gas molecule. BioEssays 26:270–280, 2004. © 2004 Wiley Periodicals, Inc. (shrink)

Cancer and its treatment pose challenges that affect not only patients but also their significant others, including intimate partners. Accumulating evidence suggests that couples’ ability to communicate effectively plays a major role in the psychological adjustment of both individuals and the quality of their relationship. Two key conceptual models have been proposed to account for how couple communication impacts psychological and relationship adjustment: the social-cognitive processing (SCP) model and the relationship intimacy (RI) model. These models posit different mechanisms and outcomes, (...) and thus have different implications for intervention. The purpose of this project is to test and compare the utility of these models using comprehensive and methodologically rigorous methods. Aims are: (1) to examine the overall fit of the SCP and RI models in explaining patient and partner psychological and relationship adjustment as they occur on a day-to-day basis and over the course of 1 year; (2) to examine the fit of the models for different subgroups (males vs. females, and patients vs. partners); and (3) to examine the utility of various methods of assessing communication by examining the degree to which baseline indices from different measurement strategies predict self-reported adjustment at 1-year follow up. The study employs a longitudinal, multi-method approach to examining communication processes including: standard self-report questionnaires assessing process and outcome variables collected quarterly over the course of 1 year; smartphone-based ecological momentary assessments to sample participant reports in real time; and laboratory-based couple conversations from which we derive observational measures of communicative behavior and affective expression, as well as vocal indices of emotional arousal. Participants are patients with stage II-IV breast, colon, rectal, or lung cancer and their spouses/partners, recruited from two NCI-designated comprehensive cancer centers. Results will be published in scientific journals, presented at scientific conferences, and conveyed to a larger audience through infographics and social media outlets. Findings will inform theory, measurement, and the design and implementation of efficacious interventions aimed at optimizing both patient and partner well-being. (shrink)

A set X of nonnegative integers is computably enumerable (c.e.), also called recursively enumerable (r.e.), if there is a computable method to list its elements. Let ε denote the structure of the computably enumerable sets under inclusion, $\varepsilon = (\{W_e\}_{e\in \omega}, \subseteq)$ . We previously exhibited a first order ε-definable property Q(X) such that Q(X) guarantees that X is not Turing complete (i.e., does not code complete information about c.e. sets). Here we show first that Q(X) implies that X has (...) a certain "slowness" property whereby the elements must enter X slowly (under a certain precise complexity measure of speed of computation) even though X may have high information content. Second we prove that every X with this slowness property is computable in some member of any nontrivial orbit, namely for any noncomputable A ∈ ε there exists B in the orbit of A such that X ≤ T B under relative Turing computability (≤ T ). We produce B using the Δ 0 3 -automorphism method we introduced earlier. (shrink)

I am in a difficult situation, being asked as a survivor to talk about people who are no longer with us, for survival always poses the problem of whether we have to deal with an event of a purely biological nature or one that, considered from an intellectual standpoint, is not merely arbitrary. Goethe frequently grappled with exactly this problem — if I may, for a moment, appeal to such a great standard. A second personal remark: when one has lived (...) as long as I have and belonged to a group that has gained such historical significance, one is constantly considered a kind of historical fragment. (shrink)

In this paper, I consider a popular version of the clever student’s reasoning in the surprise examination case, and demonstrate that a valid argument can be constructed. The valid argument is a reductio ad absurdum with the proposition that the student knows on the morning of the first day that the teacher’s announcement is fulfilled as its reductio. But it would not give rise to any paradox. In the process, I criticize Saul Kripke’s solution and Timothy Williamson’s attack on a (...) key step of the student’s reasoning. I then consider the condemned prisoner case in W. V. Quine’s paper ‘On a So-Called Paradox’. I argue that the prisoner’s reasoning as conceived by Quine is more relevant and reasonable than the student’s argument in the popular version of the surprise examination case. I also argue that Quine’s criticism of the prisoner’s reasoning is correct, and therefore that the condemned prisoner case, and the surprise examination case as well, would not generate any paradox. (shrink)