Somatic mutation plays a key role in transforming normal cells into cancerous cells. The analysis of cancer progression therefore requires the study of how point mutations and chromosomal mutations accumulate in cellular lineages. The spread of somatic mutations depends on the mutation rate, the number of cell divisions in the history of a cellular lineage, and the nature of competition between different cellular lineages. We consider how various aspects of tissue architecture and cellular competition affect the pace of mutation accumulation. (...) We also discuss the rise and fall of somatic mutation rates during cancer progression. BioEssays 26:291–299, 2004. © 2004 Wiley Periodicals, Inc. (shrink)

Awareness is a personal experience, which is only accessible to the rest of world through interpretation. We set out to identify a neural correlate of visual awareness, using brief subliminal and supraliminal verbal stimuli while measuring cerebral blood flow distribution with H215O PET. Awareness of visual verbal stimuli differentially activated medial parietal association cortex (precuneus), which is a polymodal sensory cortex, and dorsolateral prefrontal cortex, which is thought to be primarily executive. Our results suggest participation of these higher order perceptual (...) and executive cortical structures in visual verbal awareness. (shrink)

The paper introduces a concept of logic applied to a formalization of the so-called inferences preserving degrees of truth. Semantical and syntactical characterizations of three kinds of logics preserving degrees of truth are provided. The other approach than in [3] and [9] to the problem of expressing that a sentence is less true than a sentence is presented.

In the paper, tracing the traditional Hilbert-style syntactic account of logics, a syntactic characteristic of a closure operation defined on a complete lattice follows. The approach is based on observation that the role of rule of inference for a given consequence operation may be played by an ordinary binary relation on the complete lattice on which the closure operation is defined.

We study sincere-strategy preference-based approval voting , a system proposed by Brams and Sanver [1] and here adjusted so as to coerce admissibility of the votes , with respect to procedural control. In such control scenarios, an external agent seeks to change the outcome of an election via actions such as adding/deleting/partitioning either candidates or voters. SP-AV combines the voters' preference rankings with their approvals of candidates, where in elections with at least two candidates the voters' approval strategies are adjusted (...) – if needed – to approve of their most-preferred candidate and to disapprove of their least-preferred candidate. This rule coerces admissibility of the votes even in the presence of control actions, and hybridizes, in effect, approval with pluralitiy voting. We prove that this system is computationally resistant to 19 out of 22 types of constructive and destructive control. Thus, SP-AV has more resistances to control than is currently known for any other natural voting system with a polynomial-time winner problem. In particular, SP-AV is the second natural voting system with an easy winner-determination procedure that is known to have full resistance to constructive control, and unlike Copeland voting it in addition displays broad resistance to destructive control. (shrink)

We study sincere-strategy preference-based approval voting (SP-AV), a system proposed by Brams and Sanver [1] and here adjusted so as to coerce admissibility of the votes (rather than excluding inadmissible votes a priori), with respect to procedural control. In such control scenarios, an external agent seeks to change the outcome of an election via actions such as adding/deleting/partitioning either candidates or voters. SP-AV combines the voters' preference rankings with their approvals of candidates, where in elections with at least two candidates (...) the voters' approval strategies are adjusted – if needed – to approve of their most-preferred candidate and to disapprove of their least-preferred candidate. This rule coerces admissibility of the votes even in the presence of control actions, and hybridizes, in effect, approval with pluralitiy voting. We prove that this system is computationally resistant (i.e., the corresponding control problems are NP-hard) to 19 out of 22 types of constructive and destructive control. Thus, SP-AV has more resistances to control than is currently known for any other natural voting system with a polynomial-time winner problem. In particular, SP-AV is (after Copeland voting, see Faliszewski et al. [2, 3]) the second natural voting system with an easy winner-determination procedure that is known to have full resistance to constructive control, and unlike Copeland voting it in addition displays broad resistance to destructive control (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim). (shrink)

The article analyses the history of the Einfühlung concept. Theories of ‘feeling into’ Nature, works of art or feelings and behaviours of other persons by German philosophers of the second half of the nineteenth century Robert and Friedrich Vischer and Theodor Lipps are evoked, as well as similar theory of understanding (Verstehen) by Wilhelm Dilthey and Friedrich Schleiermacher, to which Dilthey refers. The meaning of the term Einfühlung within Edith Stein’s thought is also analysed. Both Einfühlung and Verstehen were criticized (...) as non-objective and naive methods consisting only in the identification of the subject with the object or the projection of feelings onto the object. The article refers to criticism by Georg Gadamer and Bertolt Brecht and proposes ways to restitute the concept of Einfühlung after this criticism, recalling the theory of empathy by Dominick Lacapra, in terms of its advantages for the historical enquiry, or the myth of Narcissus analyzed in the spirit of psychoanalysis by Julia Kristeva. The article proposes a reformulation of the concept of mimesis, connected to the Einfühlung, understood as the identification, analogy, imitation of feelings (as it was described by Lipss and Vischer). Mimesis does not necessarily mean a passive repetition and reconstruction of the feelings of the object, but serves only as a starting point for the interest of the subject for the outside world or for experiences of historical protagonists. Then there is no identification or projection of feelings, but the creative, active and critical reformulation of knowledge. It is stated that empathy is not a passive, uncritical process, but that it deals with the critical choice of the object of empathy and with an active approach to the perceived feelings and appearances. In addition to this cognitive aspect, empathy may also contribute to the analytical and valuable introspection. Furthermore empathy allows us to connect the analysis of the facts with a personal narrative and understanding of individual identity in historical knowledge. (shrink)

Formalization of reasoning which accepts rules of inference leading to conclusions whose logical values are not smaller than the logical value of the “weakest” premise leads to the concept of consequence operation preserving degrees of truth. Several examples of such consequence operation have already been considered . In the present paper we give a general notion of the consequence operation preserving degrees of truth and its characterization in terms of projective generation and selfextensionality.

The evolution and maintenance of cooperation in human and animal societies challenge various disciplines ranging from evolutionary biology to anthropology, social sciences, and economics. In social interactions, cooperators increase the welfare of the group at some cost to themselves whereas defectors attempt to free ride and neither provide benefits nor incur costs. The problem of cooperation becomes even more pronounced when increasing the number of interacting individuals. Punishment and voluntary participation have been identified as possible factors to support cooperation and (...) prevent cheating. Typically, punishment behavior is unable to gain a foothold in a population, while volunteering alone can efficiently prevent deadlocks in states of mutual defection but is unable to stabilize cooperation. The combined effects of the two mechanisms have surprisingly different consequences in finite and infinite populations. Here we provide a detailed comparison of the two scenarios and demonstrate that driven by the inherent stochasticity of finite populations, the possibility to abstain from social interactions plays a pivotal role, which paves the way for the establishment of cooperation and punishment. (shrink)

The paper deals with a generalization of the notion of partition for wider classes of binary relations than equivalences: for quasiorders and tolerance relations. The counterpart of partition for the quasiorders is based on a generalization of the notion of equivalence class while it is shown that such a generalization does not work in case of tolerances. Some results from [5] are proved in a much more simple way. The third kind of “partition” corresponding to tolerances, not occurring in [5], (...) is introduced. (shrink)

In this paper, we present a new questionnaire for the assessment of self-control as an individual trait. We describe the process of construction of this assessment tool. We also report the results of relevant validation studies. The questionnaire has two independent versions, one based on self-reports and another one based on other-reports. The first version consists of five subscales, called Initiative and Persistence, Proactive Control, Switching and Flexibility, Inhibition and Adjournment, and Goal Maintenance. Seven samples of participants took part in (...) the validation study. The second version has not been split into subscales. Both versions obtained satisfactory indices of internal consistency, assessed with Cronbach’s alpha. The NAS-50 and NAS-40 scores were highly correlated with other measures of self-control, including Tangney, Baumeister, and Boone’s self-control scale. They also proved to be entirely independent of general intelligence. In conclusion, both versions can be regarded reliable and valid enough, and therefore suitable for the assessment of trait self-control for research purposes. (shrink)

There are well-known isomorphisms between the complete lattice of all partitions of a given set A and the lattice of all equivalence relations on A. In the paper the notion of partition is generalized in order to work correctly for wider classes of binary relations than equivalence ones such as quasiorders or tolerance relations. Some others classes of binary relations and corresponding counterparts of partitions are considered.

The most fascinating aspect of human language is grammar. Grammar is a computational system that mediates a mapping between linguistic form and meaning. Grammar is the machinery that gives rise to the unlimited expressibility of human language.

We predicted that short-term training of executive control would improve both cognitive control itself and general fluid intelligence. We randomly assigned 120 high school students to the experimental and control groups. The former underwent a 14-day training of four executive functions: interference resolution, response inhibition, task switching, and goal monitoring. The latter did not train anything. The training significantly improved cognitive control and IQ. The control group also improved their IQ scores but gained less than the experimental one. However, the (...) amount of IQ scores enhancement did not correlate with the majority of indices of the training effectiveness, thus justifying the supposition that such enhancement resulted from the general effect of participation in the training rather than from the improvement of executive functions underlying Gf. (shrink)

Our purpose is to formulate a complete logic of propositions that takes into account the fact that propositions are both senses provided with truth values and contents of conceptual thoughts. In our formalization, propositions are more complex entities than simple functions from possible worlds into truth values. They have a structure of constituents (a content) in addition to truth conditions. The formalization is adequate for the purposes of the logic of speech acts. It imposes a stronger criterion of propositional identity (...) than strict equivalence. Two propositions P and Q are identical if and only if, for any illocutionary force F, it is not possible to perform with success a speech act of the form F(P) without also performing with success a speech act of the form F(Q). Unlike hyperintensional logic, our logic of propositions is compatible with the classical Boolean laws of propositional identity such as the symmetry and the associativity of conjunction and the reduction of double negation. (shrink)

Two examples of Galois connections and their dual forms are considered. One of them is applied to formulate a criterion when a given subset of a complete lattice forms a complete lattice. The second, closely related to the first, is used to prove in a short way the Knaster-Tarski’s fixed point theorem.

Two different kinds of multiple-conclusion consequence relations taken from Shoesmith and Smiley and Galatos and Tsinakis or Nowak, called here disjunctive and conjunctive, respectively, defined on a formal language, are considered. They are transferred into a bounded lattice and a complete lattice, respectively. The properties of such abstract consequence relations are presented.

The concept of multiple-conclusion consequence relation from [8] and [7] is considered. The closure operation C assigning to any binary relation r the least multiple-conclusion consequence relation containing r, is dened on the grounds of a natural Galois connection. It is shown that the very closure C is an isomorphism from the power set algebra of a simple binary relation to the Boolean algebra of all multiple-conclusion consequence relations.

The paper deals with seven propositional paraconsistent logics. Four of them are based on intuitionistic positive logic: the minimal Johansson’s logic, some two its weakenings and its extension by the law of excluded middle. The remaining three ones are their counterparts having the classical positive base. For all logics the Kripke-style semantics is provided.

The aim of the work is to present the conservative views of the journalist and historian Henryk Lisicki and the role he played in the community with which he collaborated, i.e. the Krakow conservatives called the Stańczyk Circle. The source of the article are monographs, brochures, dissertations, essays and articles published in „Przegląd Polski“ by Lisicki. In order to evaluate to what extent Lisicki’s political thought was original, and to what extent it was in conformity with the Stańczyk Circle, the (...) publications of Walerian Kalinka, Stanisław Tarnowski, Michał Bobczyński, Józef Szujski and Stanisław Koźmian were also used. While working on the topic, the author made use of the works specializing in the history of Polish and Western conservative thought published by Ryszard Ludwikowski, Bogdan Szlachta, Jacek Bartyzel, Józef Szacki and the views expressed by the members of the Stańczyk Circle such as Michał Jaskólski, Wojciech Dutka, Stanisław Filipowicz, Henryk Michalak. When examining the above issues, a comparative method was used, tracing both the similarities and differences in the ideas of Lisicki and his colleagues from the Stańczyk Circle. The main thesis formulated in the work is that although Lisicki did not belong to the group of leaders, his close intellectual ties with Stanisław Koźmian gave him a respected position among Krakow conservatives. The analysis of his works confirmed that he was also capable of original reflections which focused on the attitude of the conservatives to the nineteenth-century democratization processes, the evolution of Western absolute monarchies towards the constitution democracies and the expansion of electoral rights. Hence, it was symptomatic for Lisicki and his community to argue, inter alia, for the necessity of rapprochement with moderate liberals, the aim of which was to weaken the danger coming from the revolted masses which were being under the influence of radicals. (shrink)

Celem pracy jest analiza formalna pewnych ogólnych własności charakteryzujących wnioskowania. Autorzy twierdzą, że posiadanie tych własności jest warunkiem koniecznym, aby wnioskowanie było logicznie wartościowe. Wprowadzają aksjomatycznie pojęcie "uogólnionej operacji inferencji", które formalnie ujmuje wnioskowanie mające owe cechy. Następnie reprezentują uogólnioną operację inferencji przy użyciu relacji binarnych określonych na podzbiorach języka. Podają również taką reprezentację dla logicznej operacji konsekwencji (każda logiczna operacja konsekwencji jest uogólnioną operacją inferencji).

The aim of this article is to evaluate critically possibilities of interpreting Łukasiewicz logic by means of J.Słupecki s method presented in reference (1). In paragraph 1, we are giving a formal construction on which the method of partial interpretation Ƚ₃ is based. Paragraph 2 contains initial assumptions through which prof. J. Słupecki obtains the partial interpretation Ƚ₃ In paragraph 3, we prove that the way of obtaining this interpretation is really based on the construction from paragraph 1. Finally, in (...) paragraph 4, we present our opinion on the interpretation Ƚ₃. We prove that this interpretation cannot be obtained by means of the applied method. (shrink)

Theological Faculty of the Adam Mickiewicz University in Poznań organized a series of sessions devoted to problems of dialogue. Professor Baniak, the main organizer of those meetings, invited philosophers, theologians, pedagogues, psychologists and other intellectuals/scientists, whose area of interest was dialogue. The first conference took place in June 2001, the last in June 2007, and organizers have a hope that the endeavor would be continued. Lectures given at conferences were devoted to many subjects—classical philosophy of dialogue, dialogue in theological thought, (...) interreligious dialogue etc. (shrink)

The paper contains two concepts of implication that can be called analytic in the sense of Parry [5] or Fine [2]. Contrary to the Parry's approach, these implications do not involve S4 strict implication but the classical one. This fact refers to the similar notion of so-called demodalized analytic implication of Dunn [1] and strong implication of Vanderveken, cf. [4, 6]. The features of analytic classical implications are presented in the form of two propositional logics on the pure implicational language.

W artykule analizuje się pojęcie „proposition" (sądu w sensie logicznym) wprowadzone w pracy D. Vandervekena "What is a Proposition", stosując metody algebraiczne. Analiza ta umożliwia głębsze zrozumienie tego pojęcia, prowadzi m.in. do uogólnienia pojęcia „mocnej implikacji" (§5), jej głównym rezultatem jest pewna reprezentacja pojęcia „proposition” (§ 6).

We review mathematical models of HIV dynamics, disease progression, and therapy. We start by introducing a basic model of virus infection and demonstrate how it was used to study HIV dynamics and to measure crucial parameters that lead to a new understanding of the disease process. We discuss the diversity threshold model as an example of the general principle that virus evolution can drive disease progression and the destruction of the immune system. Finally, we show how mathematical models can be (...) used to understand correlates of long‐term immunological control of HIV, and to design therapy regimes that convert a progressing patient into a state of long‐term non‐progression. BioEssays 24:1178–1187, 2002. © 2002 Wiley‐Periodicals, Inc. (shrink)