Effects of serotonin receptor agonists and antagonists on offensive aggression in mice

The effects of serotonin receptor agonists 5-methoxytryptamine and quipazine, and antagonist mianserin on resident-intruder offensive aggression were investigated. Both agonists reduced aggression. The fact that 5-methoxytryptamine preferentially binds to 5-HT-1 receptors strongly suggest that the decreased aggression with S-methoxytryptamine was related to stimulation of an inhibitory 5-HT-1 receptor. It is also suggested that the reduction in aggression with quipazine was related to quipazine's preferential binding to the 5-HT-1 receptor. The 5-HT-2 receptor antagonist mianserin reduced aggression suggesting that 5-HT-2 receptor blockade is inhibitory for aggression. Thus, two serotonin classes of receptors may be differentially involved in offensive aggression.     

Short-term effects of residence on the testosterone responses to fighting in alpha male guinea pigs

The short-term effects on testosterone (T) levels of (a) taking blood samples, (h) fighting in one's own home cage, and (c) fighting in another male's home cage were examined in eight alpha male guinea pigs, each living together with two females and two subordinate males in their home cages for 4 months. Every male was given two 5-minute agonistic encounters, one in his home cage and one in another male's home cage. After the encounter, intruder males were returned to their home cages. Three blood samples were taken 10 minutes before and 5 and 45 minutes after the agonistic encounters (sampling times were designated as 0, 20, and 60 minutes, respectively). One week before the agonistic encounters were conducted, blood samples were taken from each male on the same time schedule (0, 20, and 60 minutes). The main findings were as follows: (1) the animals showed an increase in T-levels after an agonistic encounter in their home cages and a decline in T-levels after an agonistic encounter in the home cages of other alpha males' irrespective of being the winner or the loser and the degree of escalation during the encounter; (2) the smaller the differences in T-titers between both opponents 10 minutes before the encounter, the more escalated the agonistic encounter.     

Ethics,policy, and rare genetic disorders: the case of Gaucher disease in Israel

Gaucher disease is a rare, chronic,ethnic-specific genetic disorder affecting Jewsof Eastern European descent. It is extremelyexpensive to treat and presents difficultdilemmas for officials and patients in Israelwhere many patients live. First, high-cost,high-benefit, but low volume treatment forGaucher creates severe allocation dilemmas forpolicy makers. Allocation policies driven bycost effectiveness, age, opportunity or needmake it difficult to justify funding. Processoriented decision making based on terms of faircooperation or decisions invoking the ``rule ofrescue' risk discriminating against minoritieswho may already suffer from inequitabledistribution of heath care resources. Apartfrom cost, Gaucher disease prompts questionsabout abortion. Unlike severe geneticdisorders, Gaucher offers no grounds forabortion and, in many ways, is analogous togender based abortions that are prohibitedregardless of fetal age. Finally, Gaucherraises concerns about the disclosure of geneticinformation. These affect potential carriersasked to participate in population studies andcarriers and patients who must considerdisclosure to others. These concerns weigh theright to privacy against communal interests andbilateral commitments.     

Argument Structure and Disciplinary Perspective

Many in the informal logic tradition distinguish convergent from linked argument structure. The pragma-dialectical tradition distinguishes multiple from co-ordinatively compound argumentation. Although these two distinctions may appear to coincide, constituting only a terminological difference, we argue that they are distinct, indeed expressing different disciplinary perspectives on argumentation. From a logical point of view, where the primary evaluative issue concerns sufficient strength of support, the unit of analysis is the individual argument, the particular premises put forward to support a given conclusion. Structure is internal to this unit. From a dialectical point of view, where the focus concerns how well a critical discussion comes to a reasoned conclusion of some disputed question, the argumentation need not constitute a single unit of argument. The unit of dialectical analysis will be the entire argumentation made up of these several arguments. The multiple/co-ordinatively compound distinction is dialectical, while the linked/convergent distinction is logical. Keeping these two pairs of distinctions separate allows us to see certain attempts to characterize convergent versus linked arguments as rather characterizing multiple versus co-ordinatively compound arguments, in particular attempts of Thomas, Nolt, and Yanal, and to resolve straightforwardly conflicts, tensions, or anomalies in their accounts. Walton's preferred Suspension/Insufficient Proof test to identify linked argument structure correctly identifies co-ordinatively compound structure. His objection to using the concept of relevance to explicate the distinction between linked and convergent structure within co-ordinatively compound argumentation can be met through explicating relevance in terms of inference licenses. His counterexample to the Suspension/No Support test for identifying linked structure which this approach supports can itself be straightforwardly dealt with when the test is explicated through inference licenses.     

Temporal Interaction of Information and Belief

The temporal updating of an agent’s beliefs in response to a flow of information is modeled in a simple modal logic that, for every date t, contains a normal belief operator B _t and a non-normal information operator I _t which is analogous to the ‘only knowing’ operator discussed in the computer science literature. Soundness and completeness of the logic are proved and the relationship between the proposed logic, the AGM theory of belief revision and the notion of plausibility is discussed. A first draft of this paper was presented at the Workshop on Belief Change in Rational Agents: Perspectives from Artificial Intelligence, Philosophy and Economics, Dagstuhl (Germany), August 2005. Special Issue Formal Epistemology II. Edited by Branden Fitelson     

样例学习条件下的因果力估计

在逐个呈现因果样例的条件下,考察单一因果关系因果力估计的特点,同时检验联想解释,概率对比模型,权重DP模型,效力PC理论和pCI规则。实验让65名大学生被试估计不同化学药物影响动物基因变异的能力。实验结果表明：（1）对产生原因的因果力估计符合权重DP模型;（2）对预防原因的因果力估计较多符合效力PC理论;（3）因果力估计具有复杂多样性,难以用统一的模式加以描述和概括。     

平行分析在探索性因素分析中的应用

平行分析是探索性因素分析中用来确定所保留的凶子个数的一种方法。探索性因素分析中常用的确定因子个数的方法有特征值大于1准则和碎石图,但这两种方法又各有不足。平行分析则为探索性因素分析中所保留因子个数的确定提供了另一种新思路。本文详细介绍了平行分析的步骤、潜在逻辑以及进行平行分析所用的软件,并通过实例来说明其在探索性因素分析中如何应用。     

Rule following and rule use in the balance-scale task

Quinlan et al. [Quinlan, p., van der Mass, H., Jansen, B., Booij, O., & Rendell, M. (this issue). Re-thinking stages of cognitive development: An appraisal of connectionist models of the balance scale task. Cognition, doi:10.1016/j.cognition.2006.02.004] use Latent Class Analysis (LCA) to criticize a connectionist model of development on the balance-scale task, arguing that LCA shows that this model fails to capture a torque rule and exhibits rules that children do not. In this rejoinder we focus on the latter problem, noting the tendency of LCA to find small, unreliable, and difficult-to-interpret classes. This tendency is documented in network and synthetic simulations and in psychological research, and statistical reasons for finding such unreliable classes are discussed. We recommend that LCA should be used with care, and argue that its small and unreliable classes should be discounted. Further, we note that a preoccupation with diagnosing rules ignores important phenomena that rules do not account for. Finally, we conjecture that simple extensions of the network model should be able to achieve torque-rule performance.