Beyond Mendelism and Biometry

Historiographical analyses of the development of genetics in the first decade of the 20th century have been to a great extent framed in the context of the Mendelian-Biometrician controversy. Much has been discussed on the nature, origin, development, and legacy of the controversy. However, such a framework is becoming less useful and fruitful. This paper challenges the traditional historiography framed by the Mendelian-Biometrician distinction. It argues that the Mendelian-Biometrician distinction fails to reflect the theoretical and methodological diversity in the controversy. It also argues that the Mendelian-Biometrician distinction is not helpful to make a full understanding of the development of genetics in the first decade of the twentieth century.     

高校产学研一体化发展的实践与前瞻

本文探讨我国高校产学研一体化发展的必要性、可行性及其前景。从人类社会发展的历史特点入手，并借鉴了美国硅谷发展的经验和我国改革开放推进社会主义市场发展的需求，对高校产学研一体化发展的道路作了论述。针对目前高校产学研一体化中存在的问题，作者提出了加速高校产学研一体化发展的四条建议：1，高校产学研一体化发展必须转变观念，积极参与社会大循环；2，推进高校产学研一体化要有过硬的产品和准确的市场定位；3，高校产学研一体化发展要依托高科技园区，切实解决经费投入问题；4，高校产学研一体化发展要突出以人为本的思想，努力造就发明家和企业家。     

Molecular insights into the novel aspects of diatom biology

Diatoms are unicellular photosynthetic eukaryotes that are thought to contribute as much as 25% of global primary productivity. In spite of their ecological importance in the worlds oceans, very little information is available at the molecular level about the novel aspects of their biology. Recent advances, such as the development of gene transfer protocols, are now allowing the genetic dissection of diatom biology. Notable examples are advances in understanding the genetic basis for the silica-based bioinorganic pattern formation of their cell walls and for elucidating key aspects of diatom ecophysiology. The potentiation of current research will allow an evaluation of the use of diatoms to construct submicrometre-scale silicon structures for the nanotechnology industry and will reveal the molecular secrets underlying their ecological success. Received 29 March 2001; received after revision 31 May 2001; accepted 31 May 2001     

Choosing the Number of Conditioning Events in Judgemental Forecasting

One method for judgemental forecasting involves the use of decomposition; i.e. estimating the conditional means of an unknown quantity of interest for a finite number of conditioning events, and weighting these estimated conditional means by the estimated marginal probabilities of the corresponding conditioning events. In this paper we investigate how the level of decomposition (i.e. the number of conditioning events) affects the precision of the resulting forecast. Previous analyses assume that key parameters (the informativeness of the decomposition, and the precision of estimation for the conditional means and the marginal probabilities) remain constant as the number of conditioning events increases. However, this assumption is unreasonable, and for some parameters mathematically impossible; the values of these parameters are likely to change significantly even for small numbers of conditioning events. Therefore, we introduce models for how these key parameters may depend on the level of decomposition. We then investigate the implications of these models for the precision of the resulting forecast. In particular, we identify cases in which decomposition is never desirable, always desirable, or desirable only near the optimal number of conditioning events. This second case was not observed previously. We focus throughout on the situation likely to be of greatest interest in practice; namely, the behaviour of decomposition for relatively small numbers of conditioning events.© 1997 John Wiley & Sons, Ltd.     

Locke’s construction of the idea of power

I explain Locke’s account of the origin of our idea of power, showing that it concerns the idea of the disposition to act or change, and that this idea is constructed out of the ideas of action or change. I also show how Locke could have modified his account to avoid Hume’s criticism and argue that his neglect to do so reflects a studied neglect of taxonomy, an ambiguity in the notion of capacity, and complications in Locke’s conception of simple ideas. A comparison of the two empiricists reveals that not only do they disagree about the role of reason in the origin of our idea of power, but they are also talking about different ideas. Within the framework of Locke’s account of the origin of the idea of power, I explain why he believes that bodies only provide us with an obscure idea of active power. I conclude by defending his insight that there is a deep connection between the ability to predict and the idea of power.     

Peptides and epithelial growth regulation

Summary There is now considerable evidence implicating several peptides in the control of gastrointestinal epithelial cell proliferation and cell renewal. While some of these may act directly, many may be involved in regulating the powerful trophic effects of the intake and digestion of foold on the gut epithelium.—Several peptides have been associated with the regulation of intestinal cell proliferation. There is little doubt that gastrin is trophic to the stomach, but, its role in the rest of the gastrointestinal tract is debatable. Enteroglucagon has often been associated with increased intestinal epithelial proliferation, but at the moment all the evidence for this is circumstantial. The effects of peptide YY and bombesin warrant further study. The availability of recombinant epidermal growth factor (EGF) has recently enabled us to demonstrate a powerful trophic response to infused EGF throughout the gastrointestinal tract. The increasing availability of peptides will eventually allow the rigorous in vivo evaluation of the trophic role of these potentially very important peptides.     

Locke on measurement

Like many virtuosi in his day, the English philosopher John Locke maintained an active interest in metrology. Yet for Locke, this was no mere hobby: questions concerning measurement were also implicated in his ongoing philosophical project to develop an account of human understanding. This paper follows Locke's treatment of four problems of measurement from the early Drafts A and B of the Essay concerning Human Understanding to the publication of this famous book and its aftermath. It traces Locke's attempt to develop a natural or universal standard for the measure of length, his attempts to grapple with the measurement of duration, as well as the problems of determining comparative measures for secondary qualities, and the problem of discriminating small differences in the conventional measures of his day. It is argued that the salient context for Locke's treatment of these problems is the new experimental philosophy and its method of experimental natural history.     

Bioaccumulation processes in ecosystems

The fate of environmental pollutants — the various isotopes of elements, and inorganic or organic compounds — is a fundamental aspect of ecology and ecotoxicology, and bioaccumulation is a phenomenon often discussed in this context. Human activities have drastically altered natural concentrations of many substances in the environment and added numerous new chemicals. An understanding of the processes of bioaccumulation is important for several reasons. 1) Bioaccumulation in organisms may enhance the persistence of industrial chemicals in the ecosystem as a whole, since they can be fixed in the tissues of organisms. 2) Stored chemicals are not exposed to direct physical, chemical, or biochemical degradation. 3) Stored chemicals can directly affect an individual's health. 4) Predators of those organisms that have bioaccumulated harmful substances may be endangered by food chain effects. While former theories on the processes of bioaccumulation focused on single aspects that affect the extent of accumulation (such as the trophic level within the food chain or the lipophilicity of the chemical), modern theories are based on compartmental kinetics and the integration of various environmental interactions. Concepts include results from quantitative structure-activity relationships (QSAR), pharmacokinetics, ecophysiology and general biology, molecular genetic aspects and selection, and finally the structure of communities and man-made alterations in them.     

The effect of scale changes on repetitive patterns: Influence of 6-aminonicotinamide on feather germ number

There are many examples of patterned developing systems which are size invariant: if the total size of the system is reduced, then the pattern responds by changing its scale in such a way that the number of pattern elements remains constant. This phenomenon is one of the bases which underaly the formulation of the concept of positional information, one of the great unifying ideas in developmental biology. However, there are less common examples of patterns which are size dependent. In these, alterations of overall size lead to a reduction in pattern elements. Such size-dependent patterns are therefore of theoretical interest. Here we describe how the number of feather germs along the wing bud of the developing chick embryo responds to shortening of the limb, and consider the implications of these observations.     

一种基于图像边缘的鲁棒水印算法

本文基于图像的边缘,提出一种鲁棒水印算法．该算法使用Prewitt检测算子对载体图像进行边缘检测,并对边缘点进行选取,将水印信息嵌入在边缘点像素处的梯度方向上．由于人类视觉感知在图像边缘处的掩蔽效应,同时由于图像边缘的感知重要性和在图像处理中的稳定性,使得本文算法在不可见性和鲁棒性方面具有较好的效果．本文从理论上分析了算法抵抗攻击的能力．并在试验中得到了验证．同时结合人类视觉感知的掩蔽效应．提出了一种客观评价图像质量的方法．试验中对该方法进行了验证,并表明本文算法在该方法下具有较好的不可见性．     

Development of behavior and learning inAplysia

Summary A set of fundamental issues in neuroethology concerns the neural mechanisms underlying behavior and behavioral plasticity. We have recently analyzed these issues by combining a simple systems approach in the marine molluscAplysia with a developmental analysis aimed at examining the emergence and maturation of different forms of behavior and learning. We have focussed on two kinds of questions: 1) How are specific neural circuits developmentally assembled to mediate different types of behaviors? and 2) how is plasticity integrated with these circuits to give rise to different forms of learning? From our analysis of the development of learning and memory inAplysia, several themes have emerged: 1) Different forms of learning emerge according to different developmental timetables. 2) Cellular analogs of learning have the same developmental timetables as their respective forms of behavioral learing. 3) An analysis of non-decremented responses prior to the emergence of sensitization reveals a novel inhibitory process on both behavioral and cellular levels. 4) Sensitization emerges simultaneously in diverse response systems, suggesting an underlying general process. 5) A widespread proliferation of central neurons occurs in the same developmental stage as the emergence of sensitization, raising the possibility that some aspect of the trigger for neuronal proliferation may also contribute to the expression of sensitization.     

The transcendental method from Newton to Kant

Kant’s transcendental method, as applied to natural philosophy, considers the laws of physics as conditions of the possibility of experience. A more modest transcendental project is to show how the laws of motion explicate the concepts of motion, force, and causal interaction, as conditions of the possibility of an objective account of nature. This paper argues that such a project is central to the natural philosophy of Newton, and explains some central aspects of the development of his thinking as he wrote the Principia. One guiding scientific aim was the dynamical analysis of any system of interacting bodies, and in particular our solar system; the transcendental question was, what are the conceptual prerequisites for such an analysis? More specifically, what are the conditions for determining “true motions” within such a system—for posing the question of “the frame of the system of the world” as an empirical question? A study of the development of Newton’s approach to these questions reveals surprising connections with his developing conceptions of force, causality, and the relativity of motion. It also illuminates the comparison between his use of the transcendental method and that of Euler and Kant.     

Bovine pituitary intraglandular colloid fraction F5 localized in the rat endocrine pancreas

Summary Bovine pituitary intraglandular colloid thought to be a waste product, is the holocrine secretion of intermediate lobe cells. It is housed in the intraglandular lumen (residual lumen) and is extruded into the venous circulation of the cavernous sinuses via clefts in the capsule of the gland aligned with the intraglandular lumen. Intraglandular colloid, fraction F₅ (mol.wt 34,000), radiolabeled with (¹²⁵I)Na and injected (0.15 ml) into the right internal jugular vein of male Wistar rats, accumulated in the endocrine pancreas. Autoradiographs showed that the material had specifically localized in the capillary network of the endocrine pancreas. Since the intermediate lobe is poorly vascularized, intraglandular colloid is considered to be the transport medium for intermediate lobe materials.This study was supported by a grant from the Natural Sciences and Engineering Research Council of Canada.I would like to thank S. Choles and J. Bennett for their technical expertise with the help of P. Galvin and W. Halina. I thank members of the Central Animal Facilities, McMaster University Medical Centre, Hamilton, Ontario, for labeling the intraglandular colloid and for counting the decay rate of the tissue. I would also like to thank Drs. A. deBold and J. Kraicer, Faculty of Medicine, Queen's University, Kingston, Ontario, for their interest in this study.     

Chromosome-breaking activity of extracts of the mushroomPaxillus involutus Fries ex Batsch

Summary Dry and presoaked seeds ofNigella damascena were treated with aqueous extracts of the mushroomPaxillus involutus. At the first mitosis after the onset of germination, metaphase chromosomes showed damage independent of the origin of the mushrooms. The damaging substance(s) is (are) thermostable. Except a few achromatic gaps, all the lesions observed are of the chromosome type, i.e. are induced at the pre-synthetic G1 stage.     

Short-term forecasting of industrial production by means of quick indicators

This paper reports results on building transfer function models with linear combinations of quick indicators as inputs for very short-term prediction of the monthly time series of the volume of industrial production in Finland. The number of input variables in the transfer function models is reduced in two alternative ways: by replacing the original indicators by their two first principal components and by omitting certain indicators. The prediction accuracy of the transfer function models is checked outside the sample and found superior to that of corresponding ARIMA models. Neither of the two ways of reducing the number of input variables leads to consistently more accurate forecasts than the other. It is also found that the prediction accuracy of the transfer function models compares rather favourably with the preliminary values of the volume of industrial production published by the Central Statistical Office during the periods of rapid growth.     

Experiencing deep and global currents at a ‘Prototypical Strait’, 1870s and 1980s

Deep ocean currents are not accessible to direct human perception. Their insertion into global structures of circulation is even more profoundly removed from individual sensorial experience. But oceanographers tend to use wider concepts of experience to include instruments, traditions of observation and theoretical models. Historians and philosophers of science, as well as STS scholars, have also redefined scientific experience as operational and collective transformations of parts of the world around us into fragments of larger bodies of knowledge. This paper pursues this definition to follow the instrumental and epistemological resources available to those “observing” deep-water circulation at the Strait of Gibraltar in two very distinct moments, ca. 1870 and ca. 1985, respectively through the works of scientists like William B. Carpenter and the transnational team involved in the Gibraltar Experiment. Detecting and mapping the Gibraltar undercurrent necessitated taking data of temperature and salinity as proxies for masses of water. Making it relevant to world ocean currents required the use of models and moving across scales. In both contexts, empires of global reach provided the globalizing motivations and infrastructures.     

The role of time series analysis in the evaluation of econometric models

This paper compares the properties of a structural model—the London Business School model of the U.K. economy—with a time series model. Information provided by this type of comparison is a useful diagnostic tool for detecting types of model misspecification. This is a more meaningful way of proceeding rather than attempting to establish the superiority of one type of model over another. In lieu of a better structural model, the effects of inappropriate dynamic specification can be reduced by combining the forecasts of both the structural and time series models. For many variables considered here these provide more accurate forecasts than each of the model types alone.     

The dynamics of reason and its elusive object in Kant, Fichte and Schelling

Kant used transcendental reflection to distinguish in judgment what belongs to its form and what to its material. Regarding the form of judgment, Buchdahl’s work highlights the analogies between the different levels of judgment in Kant’s transcendental ontology. He uses the explicit contingency of judgments of the system of nature to illuminate the contingency of judgments of objects in general. In the Critique of pure reason, Kant had left much of the work of judgment to the unconscious imagination. Fichte and Schelling attempted to make conscious and determinate the work of the unconscious imagination, but found themselves unable to avoid a reflexive regress in trying to objectify and provide a foundation for the activity of the self in judgment. Buchdahl also clarifies the role Kant gave to the object in judgment, as the indeterminate ‘thinghood’ remaining once all forms of cognition are abstracted. Fichte represented this objective side of consciousness as the not-I, as the limit of the activity of the I, as an unconscious, alien element within consciousness. Schelling struggled to illuminate this unconscious object in judgment, to provide a construction of nature, without dissolving its positive presence into abstract formulations. In pursuing relentlessly Kant’s critique of judgment, Fichte and Schelling exposed its opaque points and problematized the ambition to build a complete system of philosophy.