The unfolding of the historical style in modern cosmology: Emergence,evolution, entrenchment

This paper traces the emergence, evolution and subsequent entrenchment of the historical style in the shifting scene of modern cosmological inquiry. It argues that the historical style in cosmology was forged in the early decades of the 20^th century and continued to evolve in the century that followed. Over time, the scene of cosmological inquiry has gradually become dominated and entirely constituted by historicist explanations. Practices such as forwards and backwards temporal extrapolation (thinking about the past evolutionary history of the universe with different initial conditions and other parameters) are now commonplace. The non-static geometrization of the cosmos in the early 20th century led to inquires thinking about the cosmos in evolutionary terms. Drawing on the historical approach of Gamow (and contrasting this with the ahistorical approach of Bondi), the paper then argues that the historical style became a major force as inquirers began scouring the universe for fossils and other relics as a new form of scientific practice—cosmic palaeontology. By the 1970s the historical style became the bedrock of the discipline and the presupposition of new lines of inquiry. By the end of the 20th century, the historical style was pushed to its very limits as temporal reasoning began to occur beyond a linear historical narrative. With the atemporal ‘ensemble’ type multiverse proposals, a certain type of ahistorical reasoning has been reintroduced to cosmological discourse, which, in a sense, represents a radical de-historicization of the historical style in cosmology. Some are now even attempting to explain the laws of physics in terms of their historicity.     

Dealing with active oxygen intermediates: A halophilic perspective

Although oxygen tensions in the halophilic environment are diminished, they are nevertheless sufficient for the generation of active oxygen intermediates as byproducts of metabolism. Therefore, like all other aerobes, halophilic bacteria are compelled to possess the means to detoxify potentially lethal active oxygen intermediates. This review examines the superoxide, hydrogen peroxide, hydroxyl radical and singlet oxygen scavenging capacity of the halophiles,Halobacterium spp. Specifically, it looks at the potential of the bacteria to generate active oxygen intermediates and then examines the roles of superoxide dismutase, catalase, peroxidase and catalase-peroxidase. It also looks at some non-enzymatic means of neutralizing potentially lethal active oxygen intermediates.     

Hacking’s historical epistemology: a critique of styles of reasoning

The paper begins with a detailed reconstruction of the development of Ian Hacking’s theory of scientific ‘styles of reasoning’, paying particular attention to Alistair Crombie’s influence, and suggesting that Hacking’s theory deserves to come under the title ‘historical epistemology’. Subsequently, the paper seeks to establish three critical theses. First, Hacking’s reliance on Crombie leads him to adopt an outdated historiographical position; second, Hacking is unsuccessful in his attempt to distance historical epistemology from epistemic relativism; and third, Hacking has not (yet) offered convincing criteria for individuating styles of reasoning.     

Re-orienting discussions of scientific explanation: A functional perspective

Philosophy of science offers a rich lineage of analysis concerning the nature of scientific explanation, but the vast majority of this work, aiming to provide an analysis of the relation that binds a given explanans to its corresponding explanandum, presumes the proper analytic focus rests at the level of individual explanations. There are, however, other questions we could ask about explanation in science, such as: What role(s) does explanatory practice play in science? Shifting focus away from explanations, as achievements, toward explaining, as a coordinated activity of communities, the functional perspective aims to reveal how the practice of explanatory discourse functions within scientific communities given their more comprehensive aims and practices. In this paper, I outline the functional perspective, argue that taking the functional perspective can reveal important methodological roles for explanation in science, and consequently, that beginning here provides resources for developing more adequate responses to traditional concerns. In particular, through an examination of the ideal gas law, I emphasize the normative status of explanations within scientific communities and discuss how such status underwrites a compelling rationale for explanatory power as a theoretical virtue.     

French historical epistemology: Discourse,concepts, and the norms of rationality

In recent years, analytic philosophers have begun to recognize the value of the French school of historical epistemology (as embodied by figures such as Jean Cavaillès, Gaston Bachelard, Georges Canguilhem, and Michel Foucault) for contemporary debates in the history and philosophy of science. This tradition, which some characterize as a ‘French’ approach to the philosophy of science, however, remains largely un-read by mainstream philosophers of science. This article offers an interpretation of this tradition, highlighting what the author takes to be its two central features: (i) its claim that scientific discourse is the object of epistemology and (ii) its claim that scientific concepts are the building blocks of scientific discourse.     

Effects of vitamin B12 on plasma melatonin rhythm in humans: Increased light sensitivity phase-advances the circadian clock?

Vitamin B12 (methylcobalamine) was administered orally (3 mg/day) to 9 healthy subjects for 4 weeks. Nocturnal melatonin levels after exposure to bright light (ca. 2500 lx) were determined, as well as the levels of plasma melatonin over 24 h. The timing of sleep was also recorded. Vitamin B12 was given blind to the subjects and crossed over with placebo. We found that the 24-h melatlonin rhythm was significantly phase-advanced (1.1. h) in the vitamin B12 trial as compared with that in the placebo trial. In addition, the 24-h mean of plasma melatonin level was much lower in the vitamin B12 traial than with the placebo. Furthermore, the nocturnal melatonin levels during bright light exposure were significantly lower in the vitamin B12 trial than with the placebo. On the other hand, vitamin B12 did not affect the timing of sleep. These findings raise the possibility that vitamin B12 phase-advances the human circadian rhythm by increasing the light sensitivity of the circadian clock.     

Mechanical and biochemical characterization of the contraction elicited by a calcium-independent myosin light chain kinase in chemically skinned smooth muscle

Summary The contraction induced by a Ca²⁺-independent myosin light chain kinase (MLCK-) was characterized in terms of isometric force (F_o), immediate elastic recoil (SE), unloaded shortening velocity (V_us), shortening under a constant load and ATPase activity of chemically skinned smooth muscle preparations. These parameters were compared to those measured in a Ca²⁺-induced contraction to assess the nature of cross bridge interaction in the MLCK-induced contraction. F_o developed in chicken gizzard fibers as well as SE were similar in contractions elicited by either agent. V_us in the contraction induced by MLCK-(0.36 mg/ml) was similar though averaged 39.3±8.9% less than V_us induced by Ca²⁺ (1.6x10^–6M) in the control fibers. Addition of Ca²⁺ (1.6x10^–6M) to a contraction induced by MLCK-resulted in small increases in both F_o and V_us. Shortening under a constant load was similar for both types of contractions. The contraction induced by MLCK-was accompanied by an increased rate of ATP hydrolysis. The MLCK-induced contraction is thus kinetically similar though not identical to a contraction induced by Ca²⁺. We conclude that with respect to actin-myosin interaction, MLCK- and Ca²⁺-induced contractions are similar.     

The mensuration of quadrilaterals and the generation of Pythagorean triads: A mathematical,heuristical and historical study with special reference to Brahmagupta's rules

Summary The ancient rule for the area of a quadrilateral, , is examined to show its inaccuracy and its arbitrariness, and in order to see how those using it might have become aware of its shortcomings. Consideration ofBrahmagupta's vastly more sophisticated rule, , and of the Hindu schedule of recognized quadrilateral types, leads to the question of the proper assessment to be made of this strand of Indian mathematics. The work on quadrilaterals was intimately connected with the generation of Pythagorean triangles out ofbja (=seed) numbers by the same method as had probably been used by the mathematicians of Old Babylonia. Ways in which this procedure could have arisen by induction from particular numerical calculation are shown and the rest of the study consists primarily of an investigation as to whether the same kind of approach might not also have been used to obtain the remarkable rules on quadrilaterals given byBrahmagupta. It is found that there is no compelling need to adopt the common assumption thatBrahmagupta must have had access to Alexandrian mathematics. But even if he did chance to learn of some helpful items from the works ofHero orPtolemy, it still seems necessary for a proper appreciation of his understanding of the mensuration of quadrilaterals to suppose that he would have worked such items into the contemporary Indian mathematical context in some such way as is indicated here. In particular, it is argued thatBrahmagupta, far from indulging in reckless generalization, could well have proceeded with great caution, from one amenable type of quadrilateral to another, verifying his inductions by comparing them with results given by alternative calculation methods.     

实用化光纤量子加密电话网络和高速数据传输系统——现场应用与安全管理

本文以如何应用量子通信技术满足现场应用和安全管理需求为出发点,以国内最近完成的一个在现场光纤网络上搭建的多节点量子加密电话网络和高速数据传输系统为实例,具体分析了为满足现场应用和安全管理的需求,实用化光纤量子通信系统所采用设计方案,并简单介绍了该系统实施和长期运行情况.该系统满足了重要事务对于不同应用形式及高安全等级通信的需求,并验证了实际应用环境下的可靠性和易用性,具有很好的代表性.本文也对量子通信系统应用于公共管理提出了建议.     

Making sense of Day 1 of the Two New Sciences: Galileo’s Aristotelian-inspired agenda and his Jesuit readers

This study proposes an explanation for the choice of topics Galileo addressed in Day 1 of his 1638 Two New Sciences, a section of the work which has long puzzled historians of science. I argue that Galileo’s agenda in Day 1, that is the topics he discusses and the questions he poses, was shaped by contemporary teaching commentaries on Books 3 through 8 of Aristotle’s Physics. Building on the insights and approach of theorists of reader reception, I confirm this interpretation by examining the response of professors of natural philosophy at the Jesuit Collegio Romano to Galileo’s text.     

Reception and discovery: the nature of Johann Wilhelm Ritter’s invisible rays

Ultraviolet radiation is generally considered to have been discovered by Johann Wilhelm Ritter in 1801. In this article, we study the reception of Ritter’s experiment during the first decade after the event—Ritter’s remaining lifetime. Drawing on the attributional model of discovery, we are interested in whether the German physicists and chemists granted Ritter’s observation the status of a discovery and, if so, of what. Two things are remarkable concerning the early reception, and both have to do more with neglect than with (positive) reception. Firstly, Ritter’s observation was sometimes accepted as a fact but, with the exception of C. J. B. Karsten’s theory of invisible light, it played almost no role in the lively debate about the nature of heat and light. We argue that it was the prevalent discourse based on the metaphysics of Stoffe that prevented a broader reception of Ritter’s invisible rays, not the fact that Ritter himself made his findings a part of his Naturphilosophie. Secondly, with the exception of C. E. Wünsch’s experiments on the visual spectrum, there was no experimental examination of the experiment. We argue that theorizing about ontological systems was more common than experimenting, because, given its social and institutional situation, this was the appropriate way of contributing to physics. Consequently, it was less clear in 1810 than in 1801 what, if anything, had been discovered by Ritter.     

Linear combination of forecasts: A general Bayesian model

We provide a general Bayesian model for combining forecasts from experts (or forecasting models) who might be biased and correlated with each other. The combination procedure involves debiasing and then combining unbiased forecasts. We also provide a sequential method for learning about the forecasters' biases in the process of combining information from them.     

Defining disposition concepts: A brief history of the problem

The aim of this paper is twofold. Firstly, I give a brief account of the history of the debate on the problem of defining disposition concepts from its beginning in the late 1920s until today. This account is divided into four parts, corresponding with 2, 3, 4 and 5 of the paper, each of which deals with a major period of the debate. Section 2 reports up to the mid-1950s. Section 3 deals with important contributions to the discussion between 1955 and 1958. However, the progress made around that time was far ahead of the logical theory and techniques which were needed for foundational reasons and for a better understanding of the basic notions. Some logical techniques appropriate for that aim were developed in the late 1960s and early 1970s. Though not uncontroversial, those logical techniques resulted in improvements of the insights gained in the mid-1950s; I shall report on those logical techniques and their application to the problem of defining disposition concepts in Section 4. In the early 1990s, however, the whole tradition of defining disposition concepts in terms of conditionals has been challenged by some strong counter-examples which are treated in Section 5. Finally, the second of the aims of this paper is explored in Section 6, in which I sketch very briefly the current stage of the debate by discussing and evaluating the most recent approaches to the subject.     

面向云-端融合的移动互联网应用运行平台

与传统的互联网应用相比,移动互联网应用尽管也运行于Web技术栈之上,但移动设备的便携性和多样性,带来了客户端设备计算能力相对有限、数据存储随需而变、显示屏幕大小不一、本地应用与Web应用和服务难以交互等技术挑战．为此,本文设计实现了一种面向云一端融合的移动互联网应用运行平台．首先,提出一种符合移动互联网应用体系结构的构件模型,将客户端应用划分为数据、计算、界面和服务四个部分;其次,设计了一种实现云一端资源融合的构件运行框架,支持应用数据的按需存储、计算任务的云端迁移、以及用户界面的动态切分;再次,设计了一种实现云一端服务融合的组装框架,支持客户端本地应用和传统Web应用的服务封装、和基于总线的服务即时组装;最后,基于Chrome浏览器实现了平台原型,支持基于HTML5和JavaScript的移动互联网应用,通过多个Web应用基准测试集和热点应用的实验,验证了平台的有效性和可行性．     

Linear combination of forecasts with an intercept: A bayesian approach

The standard approach to combining n expert forecasts involves taking a weighted average. Granger and Ramanathan proposed introducing an intercept term and unnormalized weights. This paper deduces their proposal from Bayesian principles. We find that their formula is equivalent to taking a weighted average of the n expert forecasts plus the decision-maker's prior forecast.     

基因功能注释——后基因组时代面临的挑战

在已经解序的、数以百计的生物基因组中,存在大量编码未知功能蛋白的基因序列。同时,众多已知功能的酶蛋白在解序的基因组中找不到对应的基因。确定未知功能基因的功能和寻找孤儿酶对应的基因是后基因组时代面临的极具挑战性的科学任务。本文综合讨论了目前基因组中基因功能注释存在的问题及解决这些问题的策略与方法。     

The imperative for inclusion: A gender analysis of genetics

It has now been more than thirty years since Joan Wallach Scott (1986) argued that gender is a legitimate and necessary category of historical analysis that applies to all fields, including genetics. In the intervening years, a substantial body of work has appeared that adds women to the historiography of genetics. While this is a necessary component for including gender as a category of analysis in genetics, it is not sufficient. Gender analysis involves the broader goal of integrating gender into the interrogation of how social factors within research practices and institutional organization influence scientific work and knowledge production in genetics. This article argues for the imperative for inclusion—including both women and gender analysis—which, taken together, not only provide a more equitable and informative picture of the discipline's development, but also yield a historiography that more faithfully reflects the activity of doing science.     

Narrow and broad styles of scientific reasoning: A reply to O. Bueno

In a recent paper, Otávio Bueno (2012) introduced a narrower understanding of Hacking's concept of styles of scientific reasoning. Although its ultimate goal is to serve a pluralist view of science, Bueno's proposal is a thought-provoking attempt at outlining a concept of style that would keep most of the original understanding's heuristic value, while providing some analytical grip on the specific details of particular scientific practices. In this reply, I consider solely this latter more proximate goal. More precisely, I assess whether or not Bueno's narrower understanding of styles could provide historians and philosophers of science with a workable unit to investigate particular transformations in scientific practices. While the author's proposal is certainly interesting overall, the usefulness of the unit it describes may be compromised by three shortcomings: 1° the extent to which the unit is meant to be narrower is indeterminate; 2° it does not improve much on the analytical capabilities of Hacking's concept; and 3° like Hacking's concept it is rather powerless to capture the dynamical character of particular scientific practices.     

Constructing dystopian experience: A Neurath-Cartwrightian approach to the philosophy of social technology

Social situations, the object of the social sciences, are complex and unique: they contain so many variable aspects that they cannot be reproduced, and it is even difficult to experience two situations that are alike in many respects. The social scientists' past experiences that serve as their background knowledge to intervene in an existent situation is poor compared to what a traditional epistemologist would consider ideal. A way of dealing with the variable and insufficient background of social scientists is by means of models. But, then, how should we characterize social scientific models? This paper examines Otto Neurath's scientific utopianism as an attempt to deal with this problem. Neurath proposes that social scientists work with utopias: broad imaginative plans that coordinate a multitude of features of a social situation. This notion can be used in current debates in philosophy of science because we notice that utopias, in Neurath's sense, are comparable to models and nomological machines in Nancy Cartwright's conception. A model-based view of science lays emphasis on the fact that scientists learn from the repeated operation of such abstract entities, just as they learn from the repetition of experiments in a laboratory. Hence this approach suggests an approximation between the natural and the social sciences, as well as between science and utopian literature. This is exemplified by analyzing the literary dystopia We, written by Yevgeny Zamyatin, to show that reasoning from and debating about utopian writings, even if fictional and pessimistic, creates phenomena of valuation, which are fundamental for constituting a background of experiences in the social sciences.     

Glycogen synthase kinase 3: A key regulator of cellular fate

The serine/threonine kinase glycogen synthase kinase-3 (GSK-3) was initially identified as a key regulator of insulin-dependent glycogen synthesis. GSK-3 was subsequently shown to function in a wide range of cellular processes including differentiation, growth, motility and apoptosis. Aberrant regulation of GSK-3 has been implicated in a range of human pathologies including Alzheimer’s disease, non-insulin-dependent diabetes mellitus (NIDDM) and cancer. As a consequence, the regulation of GSK-3 and the therapeutic potential of GSK-3 inhibitors have become key areas of investigation. This review will focus on the mechanisms of GSK-3 regulation, with emphasis on modulation by upstream signals, control of substrate specificity and GSK-3 localisation. The details of these mechanisms will be discussed in the context of specific signalling pathways. Received 30 January 2007; received after revision 5 March 2007; accepted 16 April 2007