Systematic relationships of Pityopus californicus inferred from large ribosomal subunit (26S) rRNA gene sequences

Pityopus californicus is a rare mycoheterotrophic herb that occurs in coniferous and mixed forests of western North America. Previous authors have speculated that Pityopus californicus is not a true species but is a recurring hybrid. The reputed parental candidates of P. californicus include the closely related Pleuricospora fimbriolata , Hemitomes congestum , and Monotropa hypopithys . However, a phylogenetic analysis of large ribosomal subunit (26S) rRNA gene sequences suggests that Pityopus californicus is sister to Monotropa hypopithys and not a recurring hybrid.     

Anisotropy and Corotation of Galactic Cosmic Rays

Based on some 40 billion cosmic ray events collected from 1997 to 2005 by the Tibet Air Shower Array experiment (a major scientific collaboration between China and Japan) operating at the YangBaJing Cosmic Ray Observatory (90.522 E, 30. 102 N; 4300 m above sea level) near Lhasa in Tibet, a two-dimensiondl cosmic-ray intensity map in the sky was obtained with very high directional granularity and unprecedented precision in intensity at a level of 10-4.     

Detection of a radio counterpart to the 27 December 2004 giant flare from SGR 1806-20

It was established over a decade ago that the remarkable high-energy transients known as soft gamma-ray repeaters (SGRs) are located in our Galaxy and originate from neutron stars with intense (< or = 10(15)G) magnetic fields-so-called 'magnetars'. On 27 December 2004, a giant flare with a fluence exceeding 0.3 erg cm(-2) was detected from SGR 1806-20. Here we report the detection of a fading radio counterpart to this event. We began a monitoring programme from 0.2 to 250 GHz and obtained a high-resolution 21-cm radio spectrum that traces the intervening interstellar neutral hydrogen clouds. Analysis of the spectrum yields the first direct distance measurement of SGR 1806-20: the source is located at a distance greater than 6.4 kpc and we argue that it is nearer than 9.8 kpc. If correct, our distance estimate lowers the total energy of the explosion and relaxes the demands on theoretical models. The energetics and the rapid decay of the radio source are not compatible with the afterglow model that is usually invoked for gamma-ray bursts. Instead, we suggest that the rapidly decaying radio emission arises from the debris ejected during the explosion.     

Retinal angiogenesis in development and disease

The retina has long been regarded as 'an approachable part of the brain' for investigating neurosensory processes. Cell biologists are now capitalizing on the accessibility of the retina to investigate important aspects of developmental angiogenesis, including how it relates to neuronal and glial development, morphogenesis, oxygen sensing and progenitor cells. Pathological angiogenesis also occurs in the retina and is a major feature of leading blinding diseases, particularly diabetic retinopathy. The retina and its clinical disorders have a pivotal role in angiogenesis research and provide model systems in which to investigate neurovascular relationships and angiogenic diseases.     

Significant dissipation of tidal energy in the deep ocean inferred from satellite altimeter data

How and where the ocean tides dissipate their energy are long-standing questions that have consequences ranging from the history of the Moon to the mixing of the oceans. Historically, the principal sink of tidal energy has been thought to be bottom friction in shallow seas. There has long been suggestive evidence, however, that tidal dissipation also occurs in the open ocean through the scattering by ocean-bottom topography of surface tides into internal waves, but estimates of the magnitude of this possible sink have varied widely. Here we use satellite altimeter data from Topex/Poseidon to map empirically the tidal energy dissipation. We show that approximately 10(12) watts--that is, 1 TW, representing 25-30% of the total dissipation--occurs in the deep ocean, generally near areas of rough topography. Of the estimated 2 TW of mixing energy required to maintain the large-scale thermohaline circulation of the ocean, one-half could therefore be provided by the tides, with the other half coming from action on the surface of the ocean.     

Purification and immobilization of human carbonic anhydrase B by using polyacrylamide gel

Summary Human erythrocyte carbonic anhydrase B was purified and immobilized in polyacrylamide gel. As compared to the soluble enzyme, the immobilized enzyme was considerably more resistant to heat and sulphanilamide action.Acknowledgments. I thank Prof. R. L. Brahmachary for providing me all the laboratory facilities to carry out the investigation.     

Insights into Operationalizing Communities of Practice from SSM-Based Inquiry Processes

Two systemic inquiries, based on soft systems methodology (SSM), into the potential for using community of practice (CoP) theory by an Australian-government created research and development corporation to change its knowledge management (KM) strategy, are reported. Key staff were engaged in the inquiry into how to build a third-order KM strategy based on CoPs; an exploration of key published work on CoPs yielded four SSM activity models—‘being a community practice system’; ‘doing the work of imagination sub-system’; ‘doing the work of alignment sub-system’ and ‘doing the work of engagement sub-system’. These models can be used as heuristics to aid the purposeful design of CoPs in other settings. SSM, enacted as a systemic inquiry, can be understood as a form of systemic action research, which was well equipped to deal with CoP theory and, when enacted participatively, can generate important systemic insights. The inquiry began the process of fostering an appreciation of third order KM but, on the evidence available, did not lead to on-going commitment to a CoPs-based KM strategy. Future research should acknowledge how the framing of research situations influences the research process, the importance of the design of practice change settings and the limited evidence for purposeful interventions leading to successful CoPs.     

Solutions for a cultivated planet

Increasing population and consumption are placing unprecedented demands on agriculture and natural resources. Today, approximately a billion people are chronically malnourished while our agricultural systems are concurrently degrading land, water, biodiversity and climate on a global scale. To meet the world's future food security and sustainability needs, food production must grow substantially while, at the same time, agriculture's environmental footprint must shrink dramatically. Here we analyse solutions to this dilemma, showing that tremendous progress could be made by halting agricultural expansion, closing 'yield gaps' on underperforming lands, increasing cropping efficiency, shifting diets and reducing waste. Together, these strategies could double food production while greatly reducing the environmental impacts of agriculture.