471 research outputs found
A note on the probability of generating alternating or symmetric groups
We improve on recent estimates for the probability of generating the
alternating and symmetric groups and . In
particular we find the sharp lower bound, if the probability is given by a
quadratic in . This leads to improved bounds on the largest number
such that a direct product of copies
of can be generated by two elements
Performance of commercial maize hybrids under irrigation on the Darling Downs and the St. George irrigation area
Twenty-one dent and two pop types of maize hybrids were grown under furrow irrigation in some or all of nine trials from the 1965-66 to the 1969-70 summer season. Q23, DS601, GM211, Q1280, GH134, GH128, Q692 and Q724 showed average performances above the trial mean yields. The recently introduced hybrids DeKalb 8O5A, Pioneer Q5OO and DeKalb XL45 were not as comprehensively tested but gave very promising performances. Lodging resistance was superior in these latter types. Days to 50% silking, lodging incidence, 1,000 grain weight and grain nitrogen data are presented
Female song is widespread and ancestral in songbirds
Animal science
Antiferro-quadrupole resonance in CeB6
We report experimental observation of a new type of magnetic resonance caused
by orbital ordering in a strongly correlated electronic system. Cavity
measurements performed on CeB6 single crystals in a frequency range 60-100 GHz
show that a crossing of the phase boundary TQ(B) between the
antiferro-quadrupole and paramagnetic phases gives rise to development at T
<TQ(B) of a magnetic resonance. The observed mode is gapless and correspond to
g-factor 1.62.Comment: 2 pages, Submitted to SCES05 proceeding
Magnetic resonance in cerium hexaboride caused by quadrupolar ordering
Experimental evidence of the magnetic resonance in the antiferro-quadrupole
phase of CeB6 is reported. We have shown that below orbital ordering
temperature a new magnetic contribution from localized magnetic moments (LMM)
emerge and gives rise to observed resonant phenomenon. This behaviour is hardly
possible to expect in dense Kondo system, where LMM should vanish al low
temperatures rather than emerge. From the other hand, in the quadrupole
ordering concept, where magnetism of Ce magnetic ions is solely accounted, is
difficult to explain splitting of magnetisation into components having
different physical nature. Therefore an adequate theory explaining magnetic
properties of CeB6 including magnetic resonance and orbital ordering appears on
the agenda.Comment: 4 pages, Accepted paper for MISM05 proceeding
The Influence of Murine Genetic Background in Adeno-Associated Virus Transduction of the Mouse Brain
Adeno-associated virus (AAV) vectors have become an important tool for delivering therapeutic genes for a wide range of neurological diseases. AAV serotypes possess differential cellular tropism in the central nervous system. Although several AAV serotypes or mutants have been reported to transduce the brain efficiently, conflicting data occur across studies with the use of various rodent strains from different genetic backgrounds. Herein, we performed a systematic comparison of the brain transduction properties among five AAV serotypes (AAV2, 5, 7, 8, and 9) in two common rodent strains (C57BL/6J and FVB/N), following local intrastriatal injection of AAV vectors encoding enhanced green fluorescent protein (EGFP) driven by the CBh promoter. Important differences were found regarding overall cellular tropism and transduction efficiency, including contralateral transduction among the AAV serotypes and between the mouse strains. We have further found loss of NeuN-immunoreactivity and microglial activation from AAV transduction in the different mouse strains. The important strain-specific differences from our study suggest that the genetic background of the mouse may affect AAV serotype transduction properties in the brain. These data can provide valuable information about how to choose an effective AAV vector for clinical application and interpret the data obtained from preclinical studies and clinical trials
Time capsules of biodiversity: Future research directions for groundwater-dependent ecosystems of the Great Artesian Basin
The Great Artesian Basin of Australia represents one of the largest and deepest basins of freshwater on Earth. Thousands of springs fed by the Basin are scattered across Australia’s arid zone, often representing the sole sources of freshwater for thousands of kilometers. As “islands” in the desert, the springs support endemic fauna and flora that have undergone millions of years of evolution in almost total isolation. Here, we review the current body of knowledge surrounding Great Artesian Basin springs and their significance from ecological, evolutionary, and cultural perspectives using South Australian spring wetlands as a case study. We begin by identifying the status of these springs as critical sources of groundwater, the unique biodiversity they support, and their cultural significance to the Arabana people as Traditional Custodians of the land. We then summarize known threats to the springs and their biota, both exogenous and endogenous, and the potential impacts of such processes. Finally, considering the status of these at-risk habitats as time capsules of biodiversity, we discuss lessons that can be learnt from current conservation and management practices in South Australia. We propose key recommendations for improved biodiversity assessment and monitoring of Great Artesian Basin springs nationwide, including 1) enhanced legal protections for spring biota; 2) increased taxonomic funding and capacity; 3) improved biodiversity monitoring methods, and 4) opportunities for reciprocal knowledge-sharing with Aboriginal peoples when conducting biodiversity research.P. G. Beasley-Hall, N. P. Murphy, R. A. King, N. E. White, B. A. Hedges, S. J. B. Cooper, A. D. Austin, and M. T. Guzi
Norms and trust-shaping relationships among food-exporting SMEs in Ghana
There is a marked paucity of empirically rigorous research that focuses on the impact that indigenous institutional influences can have on the internationalization strategies of entrepreneurs operating in developing countries. This study therefore explores the complex processes through which owner-managers of food-exporting SMEs in Ghana draw on cultural norms to build networks that enable internationalization, in the absence of formal institutional support. The results facilitate a better understanding of the hybridization of indigenous and global norms that underpin SME internationalization in Ghana and other developing economies, particularly in Africa. The study contributes to the theory and practice of interorganizational relationships and to international entrepreneurship in an African context
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