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Abstract  

This study examines the relative efficiency of the R&D process across a group of 22 developed and developing countries using Data Envelopment Analysis (DEA). The R&D technical efficiency is examined using a model with patents granted to residents as an output and gross domestic expenditure on R&D and the number of researchers as inputs. Under CRS (Constant Returns to Scale), Japan, the Republic of Korea and China are found to be efficient, whereas under the VRS (Variable Returns to Scale) framework, Japan, the Republic of Korea, China, India, Slovenia and Hungary are found to be efficient. The emergence of some of the developing nations on the efficiency frontier indicates that these nations can also serve as benchmarks for their efficient use of R&D resources. The inefficiency in the R&D resource usage highlighted by this study indicates the underlying potential that can be tapped for the development and growth of nations.

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Abstract

In a series of recent papers, Kanazawa has extended the Trivers-Willard hypothesis by suggesting that possession of any heritable trait that improves male reproductive success to a greater extent than it does female reproductive success will lead to a male-biased offspring sex ratio (at the individual level). He produces supporting evidence that big and tall parents have more sons than daughters. Here we test this hypothesis using two large datasets from very different populations, one British and one from rural Guatemala. There was no support for Kanazawa's extension of the Trivers-Willard hypothesis in either sample. Maternal marital status was the only predictor of offspring sex ratio but this effect was very small and limited to the British sample. Results are discussed with reference to recent studies of sex-ratio variation in humans.

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Abstract  

Using the pulse radiolysis competition kinetic technique, OH radical rate constants with 12 metal DTPA complexes were determined in neutral aerated aqueous solutions. They are in the range of /1.3–5.9/×109 dm3 mol–1s–1. To a first approximation, the rate constant was found to decrease linearly with an increase in the field strength of the metal ion (q/r2).

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Evolutionary theory suggests that maternal grandparents will invest more in their grandchildren than paternal grandparents, due to the difference between the certainty of maternity and the uncertainty of paternity. Tests of this prediction have tended to use retrospective ratings by grandchildren rather than self-reported behaviour by grandparents. Using a large-scale dataset from the Netherlands, we show significant differences between maternal and paternal grandparents in terms of frequencies of contact with their grandchildren, while controlling for a wide range of other variables. Our results show biases consistent with the paternity uncertainty hypothesis.

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Zingiber parishii Hook. f. (Zingiberaceae), a native plant of Myanmar has been reported for the first time from India. Detailed description, illustration and other relevant notes are provided.

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As suggested by previous research, childlessness can thoroughly affect the likelihood of giving and receiving help to kin, even in modern societies. In this paper we show that childless women over thirty-five have had more recent contact with their nephews/nieces than mothers. Yet, both groups showed no significant differences in contact with their uncles/aunts. This suggests heightened social investment in kin with high reproductive value by childless women compared to mothers. Results are discussed with reference to kin selection theory.

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Present study is based on the stipe anatomy of 13 selected species of pteridophytes of South India. Detailed description, key to the taxa based on stipe anatomy, photographs and descriptions are provided.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: D. Robertson, V. Thomas, H. Rieck, D. Haggard, W. Reece, J. Pappin, W. Hensley, D. Brown, C. Thomas, and P. Robinson

Abstract  

Battelle, Pacific Northwest Laboratories has recently developed, tested and field-demonstrated a technology for the direct assay of transuranic radionuclides (TRU), fission products, and activation products in a variety of radwaste packages generated at commercial nuclear power plants. This technology involves non-destructive passive neutron counting for determination of nanocurie/gram quantities of the TRU radionuclides. Direct gamma spectrometry combined with thermoluminescent dosimetry (TLD) and correlation analysis is also utilized to determine the concentrations of the fission and activation products present in the radwaste packages. Employing counting times of 10 to 20 minutes, a complete analysis of all radionuclides specified for assay by the U.S. Nuclear Regulatory Commission (in 10CFR61) prior to shallow-land disposal of commercial radwastes can be measured at concentrations at least tenfold below the least restrictive Class A waste catagory.

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Abstract

The potential of thermogravimetric analysis (TG) as a tool for the characterisation of ochre paint used in indigenous Australian bark paintings has been investigated. TG has been combined with differential scanning calorimetry (DSC) and mass spectrometry (MS) to identify and quantify the main inorganic and organic components present in the paints. The results obtained were supported by comparison with infrared spectra and XRD data obtained for the same specimens. The potential of thermal methods for the characterisation ochres has been demonstrated, with subtle differences between small samples being able to be identified.

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Journal of Flow Chemistry
Authors: Sofie Seghers, Frederik E.A. Van Waes, Ana Cukalovic, Jean-Christophe M. Monbaliu, Jeroen De Visscher, Joris W. Thybaut, Thomas S.A. Heugebaert, and Christian V. Stevens

Despite extensive research into peptide synthesis, coupling of amino acids with weakly nucleophilic heterocyclic amines remains a challenge. The need for microwave technology to promote this coupling interferes with the scalability of the process. By applying the microwave-to-flow paradigm, a library of (α-aminoacyl)amino-substituted heterocycles was continuously produced at near quantitative conversions and the reaction was scaled up successfully. Various N-Cbz-protected amino acids were activated using BtH/SOCl2 under continuous-flow conditions with excellent yields. Their coupling with heterocyclic amines was accomplished in MeCN—NMP on a preparative scale. However, performing both steps in-line resulted in an inconvenient work-up. Therefore, a two-step approach was taken, isolating the intermediate Bt-activated amino acid via simple filtration. This allows for a solvent switch to DMSO for the coupling reaction which led to excellent conversions for a broad range of substrates.

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