Notations and conventions in molecular spectroscopy: part 2. Symmetry notation

The field of Molecular Spectroscopy was surveyed in order to determine a set of conventions and symbols which are in common use in the spectroscopic literature. This document, which is Part 2 in a series, establishes the notations and conventions used for the description of symmetry in rigid molecules, using the Schoenflies notation. It deals firstly with the symmetry operators of the molecular point groups (also drawing attention to the difference between symmetry operators and elements). The conventions and notations of the molecular point groups are then established, followed by those of the representations of these groups as used in molecular spectroscopy. Further parts will follow, dealing inter alia with permutation and permutation-inversion symmetry notation, vibration-rotation spectroscopy and electronic spectroscopy.

Conservative upwind difference schemes for the Euler equations for real gas flows in a duct

In a recent paper [P. Glaister, Conservative upwind difference schemes for compressible flows in a Duct, Comput. Math. Appl. 56 (2008) 1787–1796] numerical schemes based on a conservative linearisation are presented for the Euler equations governing compressible flows of an ideal gas in a duct of variable cross-section, and in [P. Glaister, Conservative upwind difference schemes for compressible flows of a real gas, Comput. Math. Appl. 48 (2004) 469–480] schemes based on this philosophy are presented for real gas flows with slab symmetry. In this paper we seek to extend these ideas to encompass compressible flows of real gases in a duct. This will incorporate the handling of additional terms arising out of the variable geometry and the non-ideal nature of the gas.

Difference in competence for in vitro proliferation and ex vitro growth of genetically identical mature and juvenile clones of apomictic Malus species

The apomictic system in Malus wits Used Is a model to examine rejuvenation by generating genetically identical tissue culture lines that had two entirely different developmental origins: either embryo-derived tissues (juvenile clones) or somatic tissue from the adult/mature tree (mature clones). These two lines were then subsequently used to examine in vitro difference between mature (M) and juvenile (J) tissues in potential for shoot, root proliferation and ex vitro (glasshouse) growth. The M clones of M. hupehensis and M. toringoides in vitro had significantly fewer total shoots and shoot more than 2 cm in length per proliferating explant than the J clones and also rooted less efficiently. Ex vitro (glasshouse) juvenile clones had shorter internodes, a greater number of leaves and more dry weight compared to their mature counterparts.

A comparative study on the effectiveness of laboratory bioassays of entomopathogenic nematodes against desert locust nymphs Schistocerca gregaria (Acrididae:Orthoptera)

Entomopathogenic nematodes, Steinernema carpocapsae, S. feltiae (Steinernematids) Heterorhabditis indica and H. bacteriophora (Heterorhabditids) were studied to control nymphs of desert locust Schistocerca gregaria. Results of all experiments showed a significant difference in mortality percentage among all isolates. All nematodes were found more effective when exposure time was increased up to 10 days. On the other hand, both Heterorhabditids caused maximum mortality as compared to Steinernematids at 30 degree C. When different moisture levels were tested in the sand arena, a medium level of moisture (1%) caused maximum insect mortality in all isolates. However, highest concentration of each isolate (200 IJs per ml) proved to be most appropriate for maximum insect death. Similarly, both Heterorhabditis nematodes when orally applied to insects killed maximum nymphs as compared to other two Steinernematids. A similar response was observed in infectivity test when maximum percentage of IJs of both isolates of Heterorhabditis successfully penetrated into the body of locust nymphs. This research suggests some useful basic findings in developing biocides with suitable virulent of entomopathogenic nematode for controlling nymphs of desert locust.

The failure of meta-analytic asymptotics for the seemingly efficient estimator of the common risk difference

We consider the case of a multicenter trial in which the center specific sample sizes are potentially small. Under homogeneity, the conventional procedure is to pool information using a weighted estimator where the weights used are inverse estimated center-specific variances. Whereas this procedure is efficient for conventional asymptotics (e. g. center-specific sample sizes become large, number of center fixed), it is commonly believed that the efficiency of this estimator holds true also for meta-analytic asymptotics (e.g. center-specific sample size bounded, potentially small, and number of centers large). In this contribution we demonstrate that this estimator fails to be efficient. In fact, it shows a persistent bias with increasing number of centers showing that it isnot meta-consistent. In addition, we show that the Cochran and Mantel-Haenszel weighted estimators are meta-consistent and, in more generality, provide conditions on the weights such that the associated weighted estimator is meta-consistent.

Phylloxera and the grapevine: a sense of common purpose?

The purpose of life is its continuation: survival is the reason things live. Here we explore this 'basic' of biology, by reference to the extraordinary life-cycle of the aphid-like pest phylloxera, and the complexity of its relationship with its host the grapevine. The effort and ingenuity that phylloxera employs to continue itself leads to a doubt that survival alone is sufficient reason. It has frequently been suggested that the reduction of life to a catalogue of facts (by science) creates this doubt, because it robs existence of its essence (which is something other than its mechanics). The part that science is said to steal is what Robert Pirsig calls Quality-the harmonious balance of things. Pirsig seems to imply that this is something inherent in things-and independent from us. A more mundane explanation is that the difference between facts and the complete reality is us-the tendency of mind to connect freely between different kinds of information. This possibility is briefly illustrated here by a myth based on the facts of phylloxera.