The objectives of this study were to develop a high-density chromosome bin map of homoeologous group 7 in hexaploid wheat, to identify gene distribution in these chromosomes, and to perform comparative studies of wheat with rice and barley. We mapped 2148 loci from 919 EST clones onto group 7 chromosomes of wheat. In the majority of cases the numbers of loci were significantly lower in the centromeric regions and tended to increase in the distal regions. The level of duplicated loci (...) in this group was 24% with most of these loci being localized toward the distal regions. One hundred nineteen EST probes that hybridized to three fragments and mapped to the three group 7 chromosomes were designated landmark probes and were used to construct a consensus homoeologous group 7 map. An additional 49 probes that mapped to 7AS, 7DS, and the ancestral translocated segment involving 7BS also were designated landmarks. Landmark probe orders and comparative maps of wheat, rice, and barley were produced on the basis of corresponding rice BAC/PAC and genetic markers that mapped on chromosomes 6 and 8 of rice. Identification of landmark ESTs and development of consensus maps may provide a framework of conserved coding regions predating the evolution of wheat genomes. (shrink)

Insulin is a member of a family of hormones, growth factors and neuropeptides which are found in both vertebrates and invertebrates. A common ‘insulin fold’ is probably adopted by all family members. Although the specificities of receptor binding are different, there is possibility of co‐evolution of polypeptides and their receptors.

John Searle (1932-) is one of the most famous living American philosophers. A pupil of J. L. Austin at Oxford in the 1950s, he is currently Mills Professor of the Philosophy of Mind and Language at the University of California, Berkeley. In 1995 John Searle published "The Construction of Social Reality", a text which not only promises to disclose the institutional backdrop against which speech takes place, but initiate a new 'philosophy of society'. Since then "The Construction of Social Reality" (...) has been subject to a flurry of criticism. While many of Searle's interlocutors share the sense that the text marks an important breakthrough, he has time and again accused critics of misunderstanding his claims. Despite Searle's characteristic crispness and clarity there remains some confusion, among both philosophers and sociologists, regarding the significance of his proposals. This book traces some of the high points of this dialogue, leveraging Searle's own clarifications to propose a new way of understanding the text. In particular, Joshua Rust looks to Max Weber in suggesting that Searle has articulated an ideal type. In locating The Construction of Social Reality under the umbrella of one of sociology's founding fathers, this book not only makes Searle's text more accessible to the readers in the social sciences, but presents Max Weber as a thinker worthy of philosophical reconsideration. Moreover, the recharacterization of Searle's claims in terms of the ideal type helps facilitate a comparison between Searle and other social theorists such as Talcott Parsons. (shrink)

RésuméLa notion de système joue un rôle essentiel en physique. Les difficulté actuelles de la physique théorique résident en grande partie dans cette notion même. A chaque étape du développement de la physique il a fallu imaginer un processus nouveau pour effacer partiellement la coupure introduite dans la description de l'univers par la considération d'un système. Nous examinons ici le dernier procédé ou théorie fonctionnelle du corpuscule, qui consiste à se servir, pour la représentation du corpuscule, d'une image plus complète (...) que celles utilisées jusqu'ici, celle d'une fonction u d'un espace fonctionnel séparable. (shrink)

The evolutionary implications of environmental change due to organismic action remain a controversial issue, after a decades—long debate on the subject. Much of this debate has been conducted in qualitative fashion, despite the availability of mathematical models for organism–environment interactions, and for gene frequencies when allele fitness can be related to exploitation of a particular environmental resource. In this article we focus on representative models dealing with niche construction, ecosystem engineering, the Gaia Hypothesis and community interactions of Lotka–Volterra type, and (...) show that their quantitative character helps bring into sharper focus the similarities and differences among their respective theoretical contexts. (shrink)

This article won the Mind prize essay competition announced last year, for an essay defending the academic pursuit of philosophy. The author is at present a free-lance philosopher; at the time of writing the paper he was a part time lecturer at the University of Newcastle upon Tyne, in the department that has since closed. His collection of aphorisms, Sentences and Slogans has recently been published privately (for details, see 'Books Received').

There are doubtless many with personal experience of suffering, or of comforting others in distress, who would agree with Milton thus far that philosophic argument is powerless to satisfy those who in their anguish ask the question ‘Why did it happen to me?’ Yet to think so is to underestimate both the necessity and the power of reason: clarity of mind and the disposition to argue are commonly enhanced rather than diminished by suffering; and if reason is an essential part (...) of man's nature, it should serve him, if anywhere, in the trials of life. We have every justification, therefore, despite common opinion, for seeking a rational answer to the question proposed. It must, however, be admitted at the outset that there is no direct answer to the question which can both withstand critical scrutiny and bring genuine comfort to the afflicted, an answer, that is, which accepts the question as it stands with its attendant presuppositions; but there is an indirect answer, which, precisely by rejecting one or more of these presuppositions and restating the question, can indeed satisfy these two requirements. Before such an answer can be outlined, however, the question in its traditional form must be examined and the traditional answers to it critically reviewed. (shrink)

A Dirac-like equation for a massive field obeying the classical Proca equations of motion (PMO) is proposed in close analogy with Majorana’s construct for Maxwell electrodynamics. Its underlying algebraic structure is examined and a plausible physical interpretation is discussed. The behavior of the PMO equations in the presence of an external electromagnetic field is also investigated in the low energy limit, via unitary transformations similar to the Foldy-Wouthuysen canonical transformation for a Dirac fermion.

This article presents the main features of the work of Domenico Vandelli (1735-1816), an Italian-born man of science who lived a large part of his life in Portugal. Vandelli's scientific interests as a naturalist paved the way to his activities as a reformer and adviser on economic and financial issues. The topics covered in his writings are similar to those discussed by Linnaeus, with whom Vandelli corresponded. They clearly reveal that the scientific preparation indispensable for a better knowledge of natural (...) resources was also a fundamental condition for correctly addressing problems of efficiency in their economic allocation. The key argument put forward in this article is that the relationship between natural history and the agenda for economic reform and development deserves to be further analysed. It is indeed a central element in the emergence of political economy as an autonomous scientific discourse during the last decades of the eighteenth century. (shrink)

Hanlester Network v. Shalala ) marks the first test of the application of the Medicare-Medicaid anti-kickback statute to physician self-referral joint ventures. The most recent development in this ongoing litigation was the April 6, 1995 decision of the Ninth Circuit Court of Appeals, holding the Hanlester Network vicariously liable for its marketing vice president's knowing and willful violation of the antikickback statute. The vice president had offered to pay physician-investors in order to induce their referrals of program-related business.The Hanlester Network (...) was a California general partnership comprised of corporations, clinical laboratories, and individual investors. In April 1987, it entered into a management agreement on behalf of the clinical laboratories with SmithKline BioScience Laboratories. (shrink)