Rapid evolution of noncoding RNAs: lack of conservation does not mean lack of function

The mammalian transcriptome contains many nonprotein-coding RNAs (ncRNAs), but most of these are of unclear significance and lack strong sequence conservation, prompting suggestions that they might be non-functional. However, certain long functional ncRNAs such as Air and Xist are also poorly conserved. In this article, we systematically analyzed the conservation of several groups of functional ncRNAs, including miRNAs, snoRNAs and longer ncRNAs whose function has been either documented or confidently predicted. As expected, miRNAs and snoRNAs were highly conserved. By contrast, the longer functional non-micro, non-sno ncRNAs were much less conserved with many displaying rapid sequence evolution. Our findings suggest that longer ncRNAs are under the influence of different evolutionary constraints and that the lack of conservation displayed by the thousands of candidate ncRNAs does not necessarily signify an absence of function.

Vase treatments containing gibberellic acid do not increase longevity of cut Grevillea 'Sylvia' inflorescences

The longevity of Grevillea 'Sylvia' inflorescences can be very short and is influenced by exposure to ethylene. Gibberellic acid has the potential to delay senescence in some cut flowers by acting as an anti-ethylene treatment. Gibberellic acid was therefore applied to Grevillea 'Sylvia' inflorescences in vase solutions to determine its effects on longevity. Treatments with gibberellic acid did not prolong the longevity of inflorescences or influence 1-aminocyclopropane-1-carboxylic acid concentrations. Treatments at high gibberellic acid concentrations enhanced flower abscission and we therefore conclude that vase-applied gibberellic acid treatments are not suitable for extending the longevity of cut Grevillea 'Sylvia' inflorescences.

When "where'' is more important than "when": Birthplace and birthdate effects on the achievement of sporting expertise

In this study, we assessed whether contextual factors related to where or when an athlete is born influence their likelihood of playing professional sport. The birthplace and birth month of all American players in the National Hockey League, National Basketball Association, Major League Baseball, and Professional Golfer's Association, and all Canadian players in the National Hockey League were collected from official websites. Monte Carlo simulations were used to verify if the birthplace of these professional athletes deviated in any systematic way from the official census population distribution, and chi-square analyses were conducted to determine whether the players' birth months were evenly distributed throughout the year. Results showed a birthplace bias towards smaller cities, with professional athletes being over-represented in cities of less than 500,000 and under-represented in cities of 500,000 and over. A birth month/relative age effect (in the form of a distinct bias towards elite athletes being relatively older than their peers) was found for hockey and baseball but not for basketball and golf. Comparative analyses suggested that contextual factors associated with place of birth contribute more influentially to the achievement of an elite level of sport performance than does relative age and that these factors are essentially independent in their influences on expertise development.

Practicality of time-optimal two-qubit Hamiltonian simulation

What is the time-optimal way of using a set of control Hamiltonians to obtain a desired interaction? Vidal, Hammerer, and Cirac [Phys. Rev. Lett. 88, 237902 (2002)] have obtained a set of powerful results characterizing the time-optimal simulation of a two-qubit quantum gate using a fixed interaction Hamiltonian and fast local control over the individual qubits. How practically useful are these results? We prove that there are two-qubit Hamiltonians such that time-optimal simulation requires infinitely many steps of evolution, each infinitesimally small, and thus is physically impractical. A procedure is given to determine which two-qubit Hamiltonians have this property, and we show that almost all Hamiltonians do. Finally, we determine some bounds on the penalty that must be paid in the simulation time if the number of steps is fixed at a finite number, and show that the cost in simulation time is not too great.

Immobilization of aluminum chloride on MCM-41 as a new catalyst system for liquid-phase isopropylation of naphthalene

A great deal of effort has been made at searching for alternative catalysts to replace conventional Lewis acid catalyst aluminum trichloride (AlCl3). In this paper, immobilization of AlCl3 on mesoporous MCM-41 silica with and without modification was carried out. The catalytic properties of the immobilized catalyst systems for liquid-phase isopropylation of naphthalene were studied and compared with those of H/MCM-41 and H/mordenite. The structures of the surface-immobilized aluminum chloride catalysts were studied and identified by using solid-state magic angle spinning nuclear magnetic resonance (MAS NMR), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), nitrogen adsorption, and X-ray diffraction (XRD) techniques. The catalytic activity of the immobilized catalysts was found to be similar to that of acidic mordenite zeolite. A significant enhancement in the selectivity of 2,6-diisopropylnaphthalene (2,6-DIPN) was observed over the immobilized aluminum chloride catalysts. Immobilization of aluminum chloride on mesoporous silica coupled with surface silylation is a promising way of developing alternative catalyst system for liquid-phase Friedel-Crafts alkylation reactions. (C) 2002 Elsevier Science B.V. All rights reserved.

A review of the first year's experience with an automatic message-routing system for low-cost telemedicine

The Swinfen Charitable Trust has used email for some years as a low-cost telemedicine medium to provide consultant support for doctors in developing countries. A scalable, automatic message-routing system was constructed which automates many of the tasks involved in message handling. During the first 12 months of its use, 1510 messages were processed automatically. There were 128 referrals from 18 hospitals in nine countries. Of these 128 queries, 89 (70%) were replied to within 72 h; the median delay was 1.1 day. The 39 unanswered queries were sent to backup specialists for reply and 36 of them (92%) were replied to within 72 h. In the remaining three cases, a second-line (backup) specialist was required. The referrals were handled by 54 volunteer specialists from a panel of over 70. Two system operators, located 10 time zones apart, managed the system. The median time from receipt of a new referral to its allocation to a specialist was 0.2 days (interquartile range, IQR, 0.1-0.8). The median interval between receipt of a new referral and first reply was 2.6 days (IQR 0.8-5.9). Automatic message handling solves many of the problems of manual email telemedicine systems and represents a potentially scalable way of doing low-cost telemedicine in the developing world.

Listening to the 'voices' of students with severe learning difficulties through a task-based approach to research and learning in physical education

In this article, Hayley Fitzgerald, Anne Jobling and David Kirk consider the physical education and sporting experiences of a group of students with severe learning difficulties. Their study is thought provoking, not only because of the important and somewhat neglected subject matter, but equally for the research approach adopted. The way in which the study engaged with the students and the insights gained from that engagement will be of particular interest to practitioner researchers.

Random error in willingness to pay measurement: A multiple indicators, latent variable approach to the reliability of contingent values

The reliability of measurement refers to unsystematic error in observed responses. Investigations of the prevalence of random error in stated estimates of willingness to pay (WTP) are important to an understanding of why tests of validity in CV can fail. However, published reliability studies have tended to adopt empirical methods that have practical and conceptual limitations when applied to WTP responses. This contention is supported in a review of contingent valuation reliability studies that demonstrate important limitations of existing approaches to WTP reliability. It is argued that empirical assessments of the reliability of contingent values may be better dealt with by using multiple indicators to measure the latent WTP distribution. This latent variable approach is demonstrated with data obtained from a WTP study for stormwater pollution abatement. Attitude variables were employed as a way of assessing the reliability of open-ended WTP (with benchmarked payment cards) for stormwater pollution abatement. The results indicated that participants' decisions to pay were reliably measured, but not the magnitude of the WTP bids. This finding highlights the need to better discern what is actually being measured in VVTP studies, (C) 2003 Elsevier B.V. All rights reserved.

Improvement of compact terminal antenna performance by incorporating open-end slots in ground plane

This letter describes a new idea of increasing operational bandwidth of a compact planar inverted F antenna (PIFA) by introducing open-end slots in the ground plane under the radiating patch. The slots are not in the way of active modules of a wireless transceiver and thus the proposed antenna size reduction method is attractive from the point of view of practical implementation.

A longitudinal study of learning for a group of indigenous Australian university students: Dissonant conceptions and strategies

Conceptions of learning and strategies used by 15 indigenous students in three Australian universities were studied longitudinally over three years. Their academic achievements were good, but at a high cost in terms of time and effort. In spite of the fact that almost half of the students expressed higher-order (qualitative) conceptions of learning in the first year and more in the second and third years, all of the students reported using highly repetitive strategies to learn. That is, they did not vary their way of learning, reading or writing in the beginning of their studies and less than half of them did so at the end of the three years. It is argued that encountering variation in ways of learning is a prerequisite for the development of powerful ways of learning and studying.

E2F6: a member of the E2F family that does not modulate squamous differentiation

The inhibition of E2F has been demonstrated to be important in the initiation of squamous differentiation by two independent manners: promotion of growth arrest and the relief of the differentiation-suppressive properties of E2Fs. E2F6 is reported to behave as a transcriptional repressor of the E2F family. In this study, we examined the ability of E2F6 to act as the molecular switch required for E2F inhibition in order for keratinocytes to enter a terminal differentiation programme. Results demonstrated that whilst E2F6 was able to suppress E2F activity in proliferating keratinocytes, it did not modulate squamous differentiation in a differentiated keratinocyte. Furthermore, inhibition of E2F, by overexpressing E2F6, was not sufficient to sensitise either proliferating keratinocytes or the squamous cell carcinoma cell line, KJD-1/SV40, to differentiation-inducing agents. Significantly, although E2F6 could suppress E2F activity in proliferating cells, it could not inhibit proliferation of KJD-1/SV40 cells. These results demonstrate that E2F6 does not contain the domains required for modulation of squamous differentiation and imply isoform-specific functions for individual E2F family members. (C) 2004 Elsevier Inc. All rights reserved.

The state of history and the empire of metaphysics [Review]

One of the curious things about this challenging book is that its ostensible subject— the Saxon medical and political scientist Hermann Conring (1606–1681)— is not mentioned in the title. Constantin Fasolt argues that we cannot know what Conring really thought or meant in his writings, which means that his topic cannot be Conring as such and must instead be that which occludes our knowledge of him, the titular limits of history. Given that we do in fact learn a good deal about Conring from Fasolt’s book, we can only hope that the decapitation of its subject will be rectified in a subsequent edition, or perhaps by the restorative work of librarians putting together subject headings. And yet Fasolt’s decision is understandable, for Conring is indeed a stalking-horse for a much bigger quarry: historiography and the historical consciousness. By “history” Fasolt understands a way of imposing intelligibility on the world, which is founded on the twin assumptions that the past is gone and unchangeable, and that the meaning of texts can be determined by placing them in their historical contexts (ix). In challenging this mode of intelligibility, Fasolt is not attempting to improve professiona history—it’s already as good as it can be—but to displace it. He regards his work as a declaration of “independence from historical consciousness” (32). At the same time, Fasolt insists that he is not simply jumping from historiography to philosophy, or attempting to preempt history with ontology (37-39). That has been tried by Nietzsche and Heidegger, who have been tainted by Nazism (Fasolt thinks unfairly). It has also been attempted by modern philosophers from Gadamer to Foucault and Charles Taylor who, in failing to address the “violence” that its mode of intelligibility does to the world, have not succeeded in outflanking history. Perhaps, Fasolt wonders, it is only the personal experience of those who have been subject to this violence—the experience of those who have been subject to historical examination—that can break the spell of history. Fasolt’s disclaimer notwithstanding, in the course of these remarks I shall argue that he is indeed jumping from history to philosophy, or attempting to outflank history by subjecting it to a particular metaphysical understanding. I shall do so in part by sketching the recent intellectual history of this move—a historical examination that I hope inflicts as little violence as possible on Fasolt’s argument.