95,966 research outputs found
Actively decaying or just poorly preserved? Can we tell when plant and invertebrate remains in urban archaeological deposits decayed?
We have recendy argued that poorly preserved delicate macrofossil remains of plants and invertebrates in near-surface deposits in York are in active decay, rather than being preserved in stasis, part-way down the decay trajectory. Observations of both archaeological and modern deposits suggest empirically that remains either survive for a long period (if conditions are conducive) or decay rapidly (if they are not). The hypothesis that very gradual decay has led to large numbers of deposits containing remains in a similar state appears illogical. It is more likely that, where poorly preserved biological remains are found, they either decayed in the past and then were stabilised when ground conditions became anoxic, or are currently in decay. Long-term patterns of decay cannot easily be investigated experimentally, but arguments concerning patterns and rates of decay can be. Apart from the question of in-ground preservation, understanding patterns of decay will allow us to address a range of taphonomic problems fundamental to drawing archaeological information from these remains
Evidence for tanning from plant and insect remains
[FIRST PARAGRAPH] It is suggested elsewhere (Hall and Kenward forthcoming) that a bioarchaeological 'indicator group' (sensa Kenward and Hall 1997) for tanning may be recognisable. The material giving rise to this hypothesis was discovered during assessment of samples from Anglo-Scandinavian and early post- Conquest riverside deposits at Layerthorpe Bridge, York (Carrott et al. 1997). Here, large quantities of bark fragments (and the sclereids -small clumps of lignified cells characteristic of certain trees, notably oak- left when bark decays) were recorded in many samples. These gave the suspicion that the bark was being employed for some purpose, since there was usually very little wood present with it. Much the most likely process to have required bark in bulk is tanning (taken here to represent the steeping of hides in pits or vats with tree bark). Support for this came from a somewhat surprising direction. The beetle Trox scaber was unusually abundant (it was found in 30 of the samples, at a frequency of 3-6 per sample when present; five samples contained 'several' individuals and one 'many’, on the semi-quantitative scale used for recording). This contrasts with the evidence from Anglo-Scandinavian Coppergate, where it was present in a large proportion (242) of the samples but was never abundant. There were only eight cases where three or four individuals were noted, the rest being ones or twos, and the mean number of individuals per sample where the beetle was present was 1.2 (AY 14/7; Kenward, unpublished database). Thus T. scaber was significantly more abundant at the Layerthorpe Bridge site than at Coppergate
Setting people in their environment: plant and animal remains from Anglo-Scandinavian York
INTRODUCTION: For the past millennium, the inhabitants of the centre of York have, whether hey knew it or not, been living on top of a compost heap in which are preserved all kinds of remains of Anglo-Scandinavian and early post-conquest life. The preservation of this mass of organic matter has come about because, for reasons which are not fully understood, the deposits show anoxic waterlogging - in other words they have remained moist, and decay has been inhibited by lack of free oxygen. Later citizens must often have encountered these 'peaty' deposits and wondered about some of the more recognisable biological remains, as well as the numerous artefacts, surviving in them. However, it was not until the early 20th century that the value of all this material in investigating the past started to be appreciated
Business Method Patents, Innovation, and Policy
The trickle of business method patents issued by the United States Patent Office became a flood after the State Street Bank decision in 1998. Many scholars, both legal and economic, have critiqued both the quality of these patents and the decision itself. This paper discusses the likely impact of these patents on innovation. It first reviews the facts about business method and internet patents briefly and then explores what economists know about the relationship between the patent system and innovation. It concludes by finding some consensus in the literature about the problems associated with this particular expansion of patentable subject matter, highlighting remaining areas of disagreement, and suggesting where there are major gaps in our understanding of the impact of these patents.
The Financing of Research and Development
Evidence on the 'funding gap' for R&D is surveyed. The focus is on financial market reasons for underinvestment in R&D that persist even in the absence of externality-induced underinvestment. The conclusions are that 1) small and new innovative firms experience high costs of capital that are only partly mitigated by the presence of venture capital; 2) evidence for high costs of R&D capital for large firms is mixed, although these firms do prefer internal funds for financing these investments; 3) there are limits to venture capital as a solution to the funding gap, especially in countries where public equity markets are not highly developed; and 4) further study of governmental seed capital and subsidy programs using quasi-experimental methods is warranted.
Business Method Patents, Innovation, and Policy
The trickle of business method patents issued by the United States Patent Office became a flood after the State Street Bank decision in 1998. Many scholars, both legal and economic, have critiqued both the quality of these patents and the decision itself. This paper discusses the likely impact of these patents on innovation. It first reviews the facts about business method and internet patents briefly and then explores what economists know about the relationship between the patent system and innovation. It concludes by finding some consensus in the literature about the problems associated with this particular expansion of patentable subject matter, highlighting remaining areas of disagreement, and suggesting where there are major gaps in our understanding of the impact of these patents.
The Manufacturing Sector Master File: 1959-1987
This document describes the panel of publicly traded United States manufacturing firms which was created and updated at the National Bureau of Economic Research from 1978 through 1990 within the Productivity Program. The panel consists of 2726 large manufacturing firms with one to twenty-nine years of data each; the period covered by the sampling frame was 1976 through 1987, with data back to 1959 where possible. There are about 90 variable for each firm-year of data: the variables give the complete income statement, balance sheet, statement of changes, and data on the market value f the common stock. The firms on the file are identified both by their CUSIP number and by name, making it feasible to match this data to other sources. A special feature of this data file is that all exits from the file between 1976 and 1987 have been identified and the reasons for exit have been tabulated in a diskette file. This file is described in Appendix A of this document.
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