Electron localisation in 1 dimension

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WHO NEEDS TICKETS? Examining Problems in the Growing Online Ticket Resale Industry

The Internet has dramatically changed the methods by which people purchase tickets to events. In the past decade, the secondary ticket market has grown exponentially, and today the online ticket resale industry is valued at approximately $4 billion. Although there are consumer benefits to this industry growth, some of the industry practices have precipitated a consumer backlash. This was typified in 2007 when many parents, hoping to purchase tickets to the Hannah Montana Best of Both Worlds Tour, watched as tickets sold out online in only a few minutes or less. Coupled with this episode was the Ticketmaster v. RMG Technologies case, which dealt with brokers who were using software to aid in purchasing large quantities of tickets to high-profile events. Congress has finally started to pay attention in 2009. This Note argues that the time for national regulation of this growing market is now

Statistical properties of a localization-delocalization transition induced by correlated disorder

The exact probability distributions of the resistance, the conductance and the transmission are calculated for the one-dimensional Anderson model with long-range correlated off-diagonal disorder at E=0. It is proved that despite of the Anderson transition in 3D, the functional form of the resistance (and its related variables) distribution function does not change when there exists a Metal-Insulator transition induced by correlation between disorders. Furthermore, we derive analytically all statistical moments of the resistance, the transmission and the Lyapunov Exponent. The growth rate of the average and typical resistance decreases when the Hurst exponent $H$ tends to its critical value ($H_{cr}=1/2$) from the insulating regime. In the metallic regime $H\geq1/2$, the distributions become independent of size. Therefore, the resistance and the transmission fluctuations do not diverge with system size in the thermodynamic limit

Assessing the hunting practices of Namibia's commercial seal hunt

Following mounting public concerns regarding the treatment of animals in recent years, there has been increasing interest in the development of science-based guidelines for animal welfare in industries such as agriculture and hunting.1,2,3 In the latter case, for example, the European Food Safety Authority (EFSA) was requested by the European Commission, in 2007, to issue a scientific opinion regarding welfare aspects of seal hunting and to assess the most appropriate killing methods, to reduce unnecessary suffering. As part of its assessment, EFSA's Scientific opinion4 compared seal hunting to the killing of livestock in abattoirs. It noted that while slaughter conditions vary considerably, the goal should be the same: to kill animals with the minimum amount of pain, distress and fear and without causing any avoidable suffering. The report concluded that there was strong evidence that effective killing is not always practiced during seal hunts and that unnecessary and avoidable pain and suffering occurs. Subsequently, Russia ended its commercial hunt for harp seals Pagophilus groenlandicus in the White Sea in February 20095 and banned the killing of all seals under the age of one year in March of 2009.6Two months later, the European Parliament voted 550-49 in favour of a resolution banning the importation of seal hunt products, which comes into effect in 2010.7 Canada and Norway have subsequently lodged challenges against the EU ban with the World Trade Organization

The Kast Ground Based UV Spectral Survey of 79 QSOs at Redshift 2 for Lyman Alpha Forest and Metal Absorption

We present a moderate resolution (~1.15 Angstroms/pixel) survey of 79 quasars obtained using the Kast spectrograph on the Shane 3m telescope at Lick observatory. The spectra span the wavelength range of 3175-5880 Angstroms, and have typical signal to noise of 6-20 in the regions of the spectra showing Lyman alpha forest absorption. The quasars have a mean emission redshift of z=2.17, and nearly all cover the entire Lyman alpha forest between Lyman alpha and Lyman beta. Although the quasars were selected to avoid BAL, two quasars in the survey are BAL, one of which is a new discovery. We list the HI and metal ions observed in a total of 140 absorption systems. We also identify 526 emission lines, and list their observed wavelengths, along with new redshifts of the quasars. We determine the rest wavelengths of 3 emission lines or line blends in the forest to be 1070.95 +/- 1.00, 1123.13 +/- 0.51, and 1175.88 +/- 0.30 Angstroms.Comment: Submitted to the Astronomical Journa

QSOs and Absorption Line Systems Surrounding the Hubble Deep Field

We have imaged a 45x45 sq. arcmin. area centered on the Hubble Deep Field (HDF) in UBVRI passbands, down to respective limiting magnitudes of approximately 21.5, 22.5, 22.2, 22.2, and 21.2. The principal goals of the survey are to identify QSOs and to map structure traced by luminous galaxies and QSO absorption line systems in a wide volume containing the HDF. We have selected QSO candidates from color space, and identified 4 QSOs and 2 narrow emission-line galaxies (NELGs) which have not previously been discovered, bringing the total number of known QSOs in the area to 19. The bright z=1.305 QSO only 12 arcmin. away from the HDF raises the northern HDF to nearly the same status as the HDF-S, which was selected to be proximate to a bright QSO. About half of the QSO candidates remain for spectroscopic verification. Absorption line spectroscopy has been obtained for 3 bright QSOs in the field, using the Keck 10m, ARC 3.5m, and MDM 2.4m telescopes. Five heavy-element absorption line systems have been identified, 4 of which overlap the well-explored redshift range covered by deep galaxy redshift surveys towards the HDF. The two absorbers at z=0.5565 and z=0.5621 occur at the same redshift as the second most populated redshift peak in the galaxy distribution, but each is more than 7Mpc/h (comoving, Omega_M=1, Omega_L=0) away from the HDF line of sight in the transverse dimension. This supports more indirect evidence that the galaxy redshift peaks are contained within large sheet-like structures which traverse the HDF, and may be precursors to large-scale ``pancake'' structures seen in the present-day galaxy distribution.Comment: 36 pages, including 9 figures and 8 tables. Accepted for publication in the Astronomical Journa

Will the grass be greener on the other side of climate change?

Increasing atmospheric [CO2] is stimulating photosynthesis and plant production, increasing the demand for nitrogen relative to soil supply with declining global foliar nitrogen concentrations as a consequence. The effects of such oligotrophication on the forage quality of sweetveld, mixed veld, and sourveld grasslands in South Africa, which support livestock production and native ungulates, are unknown. Soil characteristics and the herbage quality of an abundant grass are described from baseline historical (mid-1980s) data collected across a sweet-mixed-sour grassland gradient in KwaZulu-Natal. Sourveld occurred on the most acidic, dystrophic soils and exhibited a pronounced decline in leaf nitrogen, digestibility, and other macronutrients during winter, in sharp contrast to sweetveld, on nutrient-rich soils, where forage quality varied little seasonally. In a carbon-enriched, warmer, and most likely drier future climate, we predict that forage quality will not be substantially altered in sweetveld where soil nutrients and temperature are not limiting but that sourveld could become ‘sourer’ because soil nutrients will be inadequate to match higher plant production promoted by elevated [CO2] and warmer and longer growing seasons. Reassessing historical data and seasonal and spatial monitoring of forage quality will enable assessment of past and future impacts of climate change on grassland forage quality. Significance: Grassland forage quality will likely decline with elevated [CO2] and warming, particularly in sourveld. Climate change could deepen and widen the sourveld winter forage bottleneck, necessitating greater supplementary feeding of livestock

The 1000 GeV gamma rays from ms pulsars

The detection of 1000 GeV gamma-rays with the characteristic 6.1 ms periodicity of the radio pulsar PSR 1953 +29 is reported. This result, significant at the 5.4 beta level, provides the first direct evidence for the association of the 6 ms radio pulsar PSR1953+29 with the gamma-ray source 2CG065+0. Extensive observations of the 1.5 ms pulsar PSR 1937 are also reported

The 1000 GeV gamma ray emission from radio pulsars

Radio pulsars have concentrated on long observations of the Crab pulsar and showed that it emits short intense bursts and a persistent weak periodic flux at gamma-ray energies 1000 GeV. It was shown that the light curve of the persistent emission was dominated by a single peak, coincident with the position of the radio and low energy gamma-ray main pulse. The results of a more detailed analysis of the structure of this main pulse are reported following an appraisal of the timing system. It is shown that at energies 1000 GeV the duration of the main pulse is not greater than 0.4 ms, which is less than that seen at all frequencies other than radio. Flux limits for the emission of 1000 GeV gamma-rays by seven other radio pulsars are reporte