Enterprise profiles in deprived areas: Are they distinctive?

This paper examines the extent to which segmenting business activity on the basis of the relative deprivation of a given area provides additional understanding (in terms of analysis and policy) that is not obtained by alternative divisions, e.g., by sector, size, etc. The paper is primarily motivated by the explicit inclusion of a deprived area dimension to many UK small business/enterprise policies introduced since 1997. We use two datasets drawn from the customer records of Barclays Bank PLC to obtain an initial analysis of the business stocks and dynamics in deprived and non-deprived areas of England. The data indicate that the deprived areas of England vary systematically from the wider economy in terms of several business stock characteristics and associated dynamics. These differences include a lower proportion of business service firms, lower female involvement in the owner-manager base and a poorer risk profile. The analysis supports the view that there are likely to be benefits from the tailoring of small business/ enterprise policies to sub-national levels

Optical dating of rock art

This article describes the principles of optical dating-an umbrella term for a family of related techniques based on the storage of radiation energy in light-sensitive traps in natural minerals-and its application to rock art. Optical dating has been applied predominantly to sand- and silt-sized grains of quartz (optically stimulated luminescence, OSL) and feldspar (infrared stimulated luminescence, IRSL) that were exposed to sunlight prior to deposition, where the age represents the time elapsed since the grains were last bleached by the sun\u27s rays. Only a few studies have used OSL or IRSL dating to constrain the age of rock paintings and engravings, and these applications can be grouped under two broad headings: dating of associated sediments and dating of rock surfaces. These studies are briefly reviewed in this chapter, together with some comments on future directions and challenges for OSL and IRSL dating of rock art

Opinion Box 11: When did modern humans first colonize Southeast Asia and Australia?

When modern humans first left Africa and entered Eurasia, they spread eastward, along the rim of the Indian Ocean. Australia lies at the end of this arc of dispersal, and our ancestors needed advanced planning capabilities and watercraft to safely island-hop through Southeast Asia and make landfall in northern Australia. Knowing when Homo sapiens first colonized this island continent has long been viewed, therefore, as providing a minimum date for the emergence of the cognitive skills and behaviors usually associated with our species

A sensitivity analysis of Southwestern climate [abstract and conclusions]

EXTRACT (SEE PDF FOR FULL ABSTRACT): We provide here an estimate of the extent that modern climate in the southwest US is sensitive to changes in several parameters that reflect global climatic changes. For the purposes of this study, we define modern climate as mean monthly values for the months of February and August (called winter and summer, respectively) of temperature and precipitation, at points representing the average of cells of dimension 7.5' on a side. The area studied surrounds the drainage basin of Death Valley, California

On the dose dependency of the bleachable and non-bleachable components of IRSL from K-feldspar: improved procedures for luminescence dating of Quaternary sediments

The infrared (IR) stimulated luminescence (IRSL) and post-IR IRSL (pIRIR) signals from K-feldspar can, for convenience, be divided into two components, bleachable and ‘non-bleachable’, where the latter corresponds to the ‘residual’ signal observed in sunlight-bleached samples. In this paper, we examine the non-bleachable component of IRSL of K-feldspar for several sedimentary samples from across Eurasia. We observed a large variability in the residual doses among these samples after prolonged exposure to sunlight. By employing multiple elevated temperature (MET) IR stimulations at 50–300 °C, we show that the residual dose increases systematically with stimulation temperature, attaining values as high as ∼50 Gy at 300 °C, even after several hours to tens of hours of exposure to unfiltered sunlight. We examined two samples in detail and found that the bleachable and non-bleachable components produced different dose response curves. Pulse annealing studies showed that the non-bleachable component is more stable than the bleachable component, suggesting that a preheat procedure cannot eliminate the non-bleachable component. Additional experiments revealed that the non-bleachable component is dose dependent. Owing to this dose dependency, we demonstrate mathematically and empirically that the simple subtraction of a residual dose from the measured equivalent dose (De) – which is the most common approach employed (if any residual dose is subtracted at all) – will result in underestimation of the actual De. We present a method to correct for the dose dependency of the residual dose, which can improve the accuracy of either MET-pIRIR or pIRIR age estimates for samples in which the non-bleachable component represents a significant fraction of the measured signals

A spectroscopic search for AGN activity in the reionization era

The ubiquity of Lyman alpha (Ly$\alpha$) emission in a sample of four bright [O III]-strong star-forming galaxies with redshifts above 7 has led to the suggestion that such luminous sources represent a distinct population compared to their fainter, more numerous, counterparts. The presence of Ly$\alpha$ emission within the reionization era could indicate that these sources created early ionized bubbles due to their unusually strong radiation, possibly due to the presence of active galactic nuclei. To test this hypothesis we have secured long integration spectra with XSHOOTER on the VLT for three $z\simeq$7 sources selected to have similar luminosities and prominent excess fluxes in the IRAC 3.6 or 4.5$\mu$m band, usually attributed to strong [O III] emission. We secured additional spectroscopy for one of these galaxies at $z$=7.15 using MOSFIRE at the Keck telescope. For this, the most well-studied source in our sample with the strongest IRAC excess, we detect prominent nebular emission from He II and NV indicative of a non-thermal source. For the other two sources at $z$=6.81 and $z$=6.85, for which no previous optical/near infrared spectroscopy was initially available, Ly$\alpha$ is seen in one and CIII] emission in the other. Although a modest sample, our results further support the hypothesis that the phenomenon of intense [O III] emission is associated preferentially with sources lying in early ionized bubbles. However, even though one of our sources at $z$=7.15 clearly indicates the presence of non-thermal radiation, such ionized bubbles may not uniquely arise in this manner. We discuss the unique advantages of extending such challenging diagnostic studies with JWST.Comment: 11 pages, 7 figures, submitted to Ap

Preliminary results of the EIP Project

The primary rationale of the Early Indian Petroglyphs Project is to investigate claims of the occurrence of Lower Palaeolithic petroglyphs in central regions of India. Other purposes of this multifacetted research project are to provide new data for the chronology of the Middle and Late Pleistocene hominin history of India; to introduce scientific methods of rock art dating in this country; and to investigate its Lower Palaeolithic stone tool industries. This project, a collaboration of Indian and Australian researchers, was commenced in 2001. It involves archaeological excavations, a range of analytical studies and intensive field surveys, and it will continue for several more years. Since its findings are of considerable significance it would not be appropriate to defer the publication of all details until after its completion. The present paper is a detailed progress report of this work, offering an overview of its theoretical base and presenting its first tangible results. They indicate that Lower Palaeolithic petroglyphs have been located at two sites, and may exist at a few others not yet adequately investigated. These initial results also provide the first datings of Indian rock art, secured from many sites of petroglyphs and pictograms in various parts of central India

Dishing the dirt: sediments reveal a famous early human cave site was also home to hyenas and wolves

Denisova Cave in Siberia\u27s Altai Mountains is one of the world\u27s most important archaeological sites. It is famous for preserving evidence of three early human groups: Neanderthals, early Homo sapiens, and a third group known as the Denisovans. Fossil bones, stone tools and ancient DNA gathered from the cave have told a story that is extremely significant for understanding the early chapters of human evolution in Asia, going back 300,000 years. But our new analysis of the cave\u27s dirt floor reveals that it was also frequented by hyenas, wolves, and even bears for much of its history

Fifty years ago, at Lake Mungo, the true scale of Aboriginal Australians\u27 epic story was revealed

This month marks the golden jubilee of a watershed event in the history of this nation that should cause all Australians to pause and reflect. On July 15, 1968, while searching for clues to past climates and ancient landscapes on land under the joint care of Paakantyi/Barkindji, Ngiyampaa and Mutthi Mutthi people, Earth scientist Jim Bowler ambled across the cremated remains of an Aboriginal woman eroding from a crescent-shaped dune flanking the shoreline of now-dry Lake Mungo in western New South Wales. The 40,000-year-old Mungo Lady and the equally ancient remains of Mungo Man, found nearby in 1974, doubled scientific estimates of how long Aboriginal people had called Australia home. The discovery taught us Aboriginal history stretched back to a time when the only humans in Europe were Neanderthals, and people had not yet reached America. The scientific, cultural and political reverberations still resonate today

Digital optical recorder-reproducer system

A mass archival optical recording and reproduction system includes a recording light source such as a laser beam focussed and directed upon an acousto-optic linear modulator array (or page composer) that receives parallel blocks of data converted from a serial stream of digital data to be stored. The page composer imparts to the laser beam modulation representative of a plurality of parallel channels of data and through focussing optics downstream of the page composer parallel arrays of optical spots are recorded upon a suitable recording medium such as a photographic film floppy disc. The recording medium may be substantially frictionlessly and stably positioned for recording at a record/read station by an air-bearing platen arrangement which is preferably thermodynamically non-throttling so that the recording film may be positioned in the path of the information-carrying light beam in a static or dynamic mode. During readout, the page composer is bypassed and a readout light beam is focussed directly upon the recording medium containing an array of previously recorded digital spots, a sync bit, data positioning bits, and a tracking band. The readout beam which has been directed through the recording medium is then imaged upon a photodetector array, the output of which may be coupled to suitable electronic processing circuitry, such as a digital multiplexer, whereby the parallel spot array is converted back into the original serial data stream