A fast analysis for thread-local garbage collection with dynamic class loading

Long-running, heavily multi-threaded, Java server applications make stringent demands of garbage collector (GC) performance. Synchronisation of all application threads before garbage collection is a significant bottleneck for JVMs that use native threads. We present a new static analysis and a novel GC framework designed to address this issue by allowing independent collection of thread-local heaps. In contrast to previous work, our solution safely classifies objects even in the presence of dynamic class loading, requires neither write-barriers that may do unbounded work, nor synchronisation, nor locks during thread-local collections; our analysis is sufficiently fast to permit its integration into a high-performance, production-quality virtual machine

Speaking of science: BBC science broadcasting and its critics, 1923–64

Several times in the BBC’s history, from the 1920s to the 1960s, scientific organisations (mainly the British Association) and numerous eminent scientists attempted to influence the management of science broadcasting. These attempts usually consisted of visits by scientific deputations to the BBC to argue for the reorganisation of science broadcasting. The historical part of the thesis narrates the so-far unpublished story of these interventions at the BBC, drawing on archival primary sources. The thesis sets these interventions in their historical context, and also in the context of BBC science production. The historical context of science production at the BBC, described here, is another little researched and largely unknown topic. The interventions are shown to have been strikingly consistent over several decades. Scientists argued that the public should be better informed about science, and that the BBC had a duty to promote the public understanding of science. To facilitate this, scientists argued that science production should be centralised, and that scientists should be given significant control over science programme planning. The responses of BBC managers to these interventions are shown also to have been strikingly consistent. Managers reiterated the professionalism and competence of production staff, and presented evidence of the BBC’s commitment to science programming. The thesis draws on several bodies of scholarship in concert to gain theoretical insight into these interventions. Specifically, theoretical ideas relating to science communication, boundary work, and the construction of scientific authority give analytical purchase on the conduct of the scientists. Similarly, theoretical ideas on the nature of professionalism, public-service broadcasting, and the relationship of organisational structure to behaviour give insight into the conduct of BBC managers, and into the conduct of the scientists. This theoretical background shows how the resolution of the issue in 1964 served a strategic function for the BBC

Plant viruses.

Cucumber mosaic virus in legumes, 85A024, 85A122, 85A123, 85A153, 85A163, 85A217, 85A219. Alfalfa mosaic virus in annual medics

HD 179949b - a close orbiting extrasolar giant planet with a stratosphere?

The original article can be found at: http://www3.interscience.wiley.com Copyright Blackwell Publishing. DOI: 10.1111/j.1365-2966.2008.13831.xWe have carried out a search for the 2.14-μm spectroscopic signature of the close orbiting extrasolar giant planet, HD179949b. High-cadence time-series spectra were obtained with the Cryogenic high-resolution InfraRed ´ Echelle Spectrograph at Very Large Telescope, Unit 1 on two closely separated nights. Deconvolution yielded spectroscopic profiles with mean signal-to-noise ratios of several thousand, enabling the near-infrared contrast ratios predicted for the HD179949 system to be achieved. Recent models have predicted that the hottest planets may exhibit spectral signatures in emission due to the presence of TiO and VO which may be responsible for a temperature inversion high in the atmosphere.We have used our phase-dependent orbital model and tomographic techniques to search for the planetary signature under the assumption of an absorption line dominated atmospheric spectrum, where T and V are depleted from the atmospheric model, and an emission line dominated spectrum, where TiO and VO are present. We do not detect a planet in either case, but the 2.120–2.174-μm wavelength region covered by our observations enables the deepest near-infrared limits yet to be placed on the planet/star contrast ratio of any close orbiting extrasolar giant planet system. We are able to rule out the presence of an atmosphere dominated by absorption opacities in the case of HD179949b at a contrast ratio of Fp/F∗ ∼ 1/3350, with 99 per cent confidence.Peer reviewe

Virus diseases of lupins virus diseases of pastures

Virus diseases of lupins. Bean yellow mosaic virus and cucumber mosaic virus Effect of CMV isolate Effect of pod position Effect of dry conditions on establishment Effect of cultivar on seed transmission rates Effect of reflective mulch Survey of commercial seed stocks. Virus disease of pastures Bean yellow mosaic virus and cucumber and alfalfa mosaic viruses Symptoms Distribution Seed-borne infection Persistence Recommendations for control Lupin phyllody disorder Barley yellow dwarf virus Publication

Scale-invariant moving finite elements for nonlinear partial differential equations in two dimensions

A scale-invariant moving finite element method is proposed for the adaptive solution of nonlinear partial differential equations. The mesh movement is based on a finite element discretisation of a scale-invariant conservation principle incorporating a monitor function, while the time discretisation of the resulting system of ordinary differential equations is carried out using a scale-invariant time-stepping which yields uniform local accuracy in time. The accuracy and reliability of the algorithm are successfully tested against exact self-similar solutions where available, and otherwise against a state-of-the-art h-refinement scheme for solutions of a two-dimensional porous medium equation problem with a moving boundary. The monitor functions used are the dependent variable and a monitor related to the surface area of the solution manifold

The use of coconut oil/diesel blends as a fuel for compression ignition engines (ODNRI Bulletin No. 31)

This bulletin describes experimental and evaluative work carried out by the Overseas Development Natural Resources Institute (ODNRI) to investigate fuelling of a standard compression ignition engine with blends of coconut oil and diesel. Initial studies were made of fuel-related properties for pure coconut oil and for a full range of blends with diesel. A major upgrading of the standard engine's fuel filtration system was necessary but thereafter it was found that a blend of 80% coconut oil in diesel, when heated to 45°C, provided a technically feasible substitute fuel. A limited duration engine trial was completed with this alternative arrangement to assess maintenance and operational requirements. On the basis of these results a preliminary economic evaluation was made of the potential for wider adoption of this type of substitute fuelling. Whilst this indicated that at prevailing prices of coconut oil relative to diesel this was unattractive, circumstances were identified in which this technology could have potential application

Purple dwarfs : New L subdwarfs from UKIDSS and SDSS

This is an Open Access article distributed under the terms of the Creative Commons Attribution License 2.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.The first L subdwarf was a discovered only ten years ago. Less than ten L subdwarfs been published in the literature to date. Metal-poor ultracool atmospheres has not been well understood. Halo mass function cross substellar limit has not been measured. We used UKIDSS and SDSS to search for L subdwarfs. We have confirmed some new L subdwarfs and are following up more candidates with ground based large telescopes. We discussed spectral features of L subdwarfs and halo brown dwarfs