bluuebunny/crossref_metadata_2025_split huggingface dataset:
PRICES OF SLAVES IN WEST AND WEST‐CENTRAL AFRICA: TOWARD AN ANNUAL SERIES, 1698–1807
Authors: Richardson David 
Published: May 2007

ABSTRACTCurrently available price series for slaves during the eighteenth century need to be treated with much caution, and it seems unlikely that large quantities of new evidence will be unearthed. Further progress toward the creation of more reliable price series will thus require new methods of estimation. In this paper, a new price series for slaves at the African coast is calculated using data relating to the number of slaves shipped from the coast by British traders and the value of trade goods bartered for them.
TERMS OF TRADE AND ECONOMIC GROWTH IN NINETEENTH CENTURY BRITAIN *
Authors: Irwin Douglas A. 
Published: May 2007

ABSTRACTInternational trade and economic growth have been considered intimately linked in nineteenth century Britain. Conventional estimates of Britain's gross national product, however, fail to account for changes in the terms of trade and may be misleading indicators of changes in real income. Revised figures that incorporate terms of trade changes are presented here. One finding is that conventional estimates of GNP overstate growth in real income early in the century when the terms of trade deteriorated.
PRICE AND WELFARE EFFECTS OF OLIGOPOUSTIC MERGERS
Authors: McElroy F. William 
Published: May 2007

ABSTRACTWhen oligopolists merge, the new firm enjoys a lower cost structure than any of its premerger constituent parts. This is because of rationalization economies which are created as facilities previously operated at disparate marginal cost levels come under common control. The resultant price‐decreasing force is countered by the loss of competition due to the merger. The latter can stem not only from reduction in the number of competitors, but also from the possibility that, with a more concentrated market structure, firms’conjectures about each others’reactions will move in the direction of being more cooperative. The paper shows that, under normal conditions, the effects of diminished competition outweigh those of rationalization so that a price increase will result from the merger. In addition, the equivalence of merger to the imposition of taxes is exploited to derive a market‐share based test for mergers to cause welfare decreases. This complements a test proposed by Farrell and Shapiro that works only for welfare increases.
POLITICAL PARTIES AND GOVERNMENT BEHAVIOUR
Authors: Wren Colin 
Published: May 2007

ABSTRACTThe paper attempts to explain and identify differences in party political behaviour in office, in terms of the weight they attach to unemployment and inflation. Reasons are advanced to suggest that incumbents do not take‐up the median voter position, but instead pursue differentiated policies (i.e. make choices) which are both consistent with their known ideology (preferences) and with maximizing their share of the vote at the next election. The model is fitted with UK data, and the results are encouraging, providing some support for the notion that parties pursue politically‐motivated policies throughout their term of office and not just in the run‐up to elections.
COMMON STOCHASTIC TRENDS: EVIDENCE FROM THE LONDON METAL EXCHANGE
Authors: Agbeyegbe Terence D. 
Published: May 2007

ABSTRACTRecent evidence from cointegration theory points towards the efficiency of the London Metal Exchange. We show that on theoretical grounds this evidence could be misleading. We also conduct multivariate and univariate unit roots tests on prices of three different metals, namely: copper, lead and zinc. The price data are seasonal and unadjusted quarterly data from the London Metal Exchange and they cover the period from 1972.1–1987.4. The evidence presented here supports the presence of common stochastic trends in metal price movements.
The growth of UK health expenditure
Authors: Whynes David K. 
Published: May 2007

ABSTRACTOver the past four decades, spending on health care in the United Kingdom has accounted for a rising share, both of total public spending and of the total output of the economy. Other industrial economies have had similar experiences, although the peculiar nature of the UK health service makes the general explanations offered for such expenditure growth inappropriate. Health spending growth in the UK, for the period 1949–89, is found to be strongly associated with output growth, and reasons to explain this relationship are advanced. The relationship's continued stability in the light of the 1989 health service reforms is questioned.
The Use of Tetrahymena to Evaluate the Effects of Gamma Radiation on Essential Nutrilites*
Authors: ELLIOTT A. M. , BROWNELL L. E. , GROSS J. A. 
Published: May 2007

The complete synthetic medium for the growth of Tetrahymena pyriformis E was subjected to gamma‐radiation from cobalt60. A dose‐response curve indicated the range of radiation which damaged the medium so that growth of Tetrahymena was inhibited.The essential vitamins and amino acids which comprise the medium were individually irradiated in solution. Media were prepared with single irradiated components and tested for their ability to support growth of the protozoa.Thiamine, riboflavin, pantothenate, pyridoxine, folic acid, and thioctic acid were destroyed by less than 1 × 106 rep, while 2 × 106 rep was required to inactivate nicotinic acid. Most amino acids proved to be relatively radiation‐resistant. At the high radiation levels of 1 × 107 rep and 2.3 × 107 rep respectively, only serine and methionine were damaged. All other amino acids remained biologically active even after receiving 2.3 × 107 rep, the highest level of radiation employed. Organoleptic observations, however, showed radiation‐caused color and odor changes in many of those amino acids whose biological activity for Tetrahymena was unaffected. The nucleotide, guanylic acid, was also inactivated at 2.3 × 107 rep.
Studies in Carotenogenesis. Some Observations on Carotenoid Synthesis in Two Varieties of Euglena gracilis.
Authors: GOODWIN T. W. , JAMIKORN M. 
Published: May 2007

Euglena gracilis v. bacillaris and E. gracilis v. fuscopunctata produce the same three carotenoids, β‐carotene, lutein and neoxanthin in approximately the same relative amounts. Lutein is the major pigment and β‐carotene represents about 10–15% of the total. The concentration of carotenoids in E. gracilis v. bacillaris is very high, reaching 700 mg./100 g. dry weight.Streptomycin (0.02%, w/v) and darkness reduced growth of E. gracilis v. bacillaris by about 50% and carotenoid synthesis by about twenty times. Diphenylamine (1/70,000) reduced growth and carotenoid synthesis equally (about 50%). In no case was the synthesis of more saturated polyenes (the phytofluene series) stimulated.The nature of the eye spot pigment is discussed.
The Blood Protozoa of Seventeen Species of Sparrows and Other Fringillidae
Authors: MANWELL REGINALD D. 
Published: May 2007

SUMMARY. A total of 1037 birds, belonging to 17 species of Fringillidae (order Passeres) and nearly all collected in or near Syracuse, N. Y., were examined for blood parasites. Of the species of avian malaria, Plasmodium cathemerium occurred most frequently, followed by P. hexamerium, P. relictum, P. elongatum, and P. circumflexum. Other species were not seen, although some (e.g. P. nucleophilum, P. polare, P. vaughani) are known to occur in Central New York.A number of song, chipping, and field sparrows were given experimental inoculations of Plasmodium vaughani‐infected blood and liberated. A few were recaught at varying intervals, but none were infected, suggesting that these species are insusceptible to this type of avian malaria.Malaria in song sparrows, which were caught in large numbers, is common and probably endemic, not varying greatly in frequency from year to year. But the incidence shows a sharp peak in the spring, most cases apparently being low‐grade relapses, which probably serve to reestablish the infection in the new crop of mosquitoes. There are indications that Haemoproteus and Leucocytozoon behave similarly.Infection with these last two parasites occurred in most of the species examined, but the incidence varied greatly, being especially high in white‐throated and white‐crowned sparrows. Reproductive stages of Haemoproteus were observed in the lungs of song and chipping sparrows.
A Biometrical Study of the Oocyst of Eimeria brunetti, a Parasite of the Common Fowl*
Authors: BECKER ELERY R. , ZIMMERMANN WILLIAM J. , PATTILLO WALTER 
Published: May 2007

SUMMARY. An unsporulated oocyst of Eimeria brunetti encountered at random in a mild infection would probably be 13.8 to 33.7 μ long and 12.4 to 26.2 μ wide. Its shape‐index (length/width) would probably lie between the extremes of 1.0 and 1.6. Its dimensions would probably not change significantly during the sporulation process. If a sample of the oocysts randomly encountered happened to be the progeny of a single inoculation, their mean size would depend, among other things, on the day of the patent period the sample was taken, as well as on certain undetermined factors in the individual host; but their mean length would probably lie between 21.1 μ and 27.1 μ and their mean width between 17.5 μ and 21.7 μ. The mean dimensions would probably be smaller early in the patent period of the infection than later.By a certain process of reasoning it was deduced that the individual components of an “ideal” sample of oocysts of E. brunetti would range from 18.4 μ to 28.4 μ in length and from 15.2 μ to 23.9 μ in width; their mean dimensions with standard deviations would be about 23.4 ± 2.0 μ by 19.7 ± 1.7 μ, and their shape‐indexes would range from 1.0 to 1.4 and average about 1.19. The lengths, widths, and shape‐indexes of the oocysts would usually describe unimodal frequency distribution curves, most of them near‐symmetrical. The mean size of the matured spores produced inside such oocysts would probably be close to 13.2 by 7.5 μ, and their shape‐index near 1.76. As a matter of fact, such a sample would be encountered only by pure chance, because the size of the oocyst of E. brunetti remains an undetermined quantity until it is translated into a veritable definition that takes account not only of its variability under one set of conditions, but also of its capacity to respond to other conditions, among them the size of the inoculation, the influence of the individual host, and the day of the infection.It would be hazardous to discriminate between or among species of coccidia on the basis of oocyst measurements, particularly when they lack conspicuous diagnostic morphological or physiological features of another nature. As Cheissin reflected, observations on a single finding of oocysts, particularly when they are sparse in numbers, are not a substitute for repeated observations on oocysts issuing from the host at different times and over a considerable period.
The Development of Megaloschizonts of Leucocytozoon simondi Mathis and Leger.*
Authors: COWAN ARCHIBALD B. 
Published: May 2007

SUMMARY. Susceptible ducklings were exposed to natural infection during a limited time, and infections of supposedly known duration were obtained. Slides of tissues from these ducklings were prepared by common histological techniques. Comparative materials were provided by cooperators. On the basis of study of these tissues what seems a logical description of development of megaloschizonts of Leucocytozoon simondi was formulated.The earliest stage found was the trophozoite. There is no evidence of schizogony in this form; the only internal structure is the nucleus. Prior to any schizogony there is a marked increase in the amount of chromatin in the nucleus, especially on the periphery.It is hypothesized that as the chromatin increases, buds are evaginated from the margin of what may then be called the central body and are set off to form spherical primary cytomeres. The chromatin of primary cytomeres first diffuses and then proliferates to form peripheral clusters. These clusters of chromatin separate to form secondary cytomeres which continue to multiply in the same manner.The production of cytomeres by the central body and by division of primary and secondary cytomeres eventually fills the cytoplasmic area of the megaloschizont. Apparently pressure within the schizont then shapes the course of further development. The central body ceases to function as a primordium and becomes compressed. The multiplying cytomeres become smaller and more granular in appearance, and their chromatin becomes more concentrated. Merozoite‐like bodies are eventually produced. These reproduce until the central body is greatly compressed and the membrane enclosing the megaloschizont is ruptured and releases the merozoites.
The Breeding System and Distribution of Tetrahymena pyriformis.*
Authors: GRUCHY DAVID F. 
Published: May 2007

SUMMARY. Seven hundred twenty samples of water from 46 states and the province of Ontario, Canada, were collected and examined for Tetrahymena pyriformis. Thirty‐four hundred clonal cultures of the ciliate were isolated from the 154 (21%) positive samples and grown axenically in peptone medium.The breeding behavior of strains from these 154, sources was investigated by mixing clonal cultures in various combinations. Eight sources yielded selfing strains and 52 yielded strains capable of mating only in certain combinations. Thirty new mating types in seven new non‐interbreeding varieties were discovered. Ninety of the 154 collections yielded non‐conjugating strains. Fifty of these proved to be amicronucleate.Distribution of variety 2 organisms was the most widespread; 22 collections from 11 states and Ontario, Canada, were obtained. Variety 3 was collected 14 times from seven states. Other varieties were found less often. The ciliate was found about as often in running as in standing water, but certain varieties were found predominantly in one or the other habitat.
Studies on Trichomonads. II. The Metabolism of a Trichomonas batrachorum‐type Flagellate from the Cecum of Swine
Authors: DORAN DAVID J. 
Published: May 2007

SYNOPSIS. Certain aspects of the metabolism of a Trichomonas batrachorum‐type flagellate from the cecum of swine were studied. This trichomonad (1) oxidized glucose, mannose, maltose, sucrose, and inulin, (2) was incapable of oxidizing Krebs' cycle intermediates, (3) possessed peroxide‐splitting capabilities, (4) was inhibited by only iodoacetate and arsenite, and (5) formed acid(s) aerobically. Although there was no effect on oxygen uptake, pyruvate and lactate increased the anaerobic evolution of gas(es). In addition to CO2, other gas, not absorbed by KOH, was produced anaerobically.Compared with other porcine trichomonads, the metabolism of this small trichomonad resembles most closely that of the large cecal trichomonad, T. suis. However, the smaller trichomonad had a generally lower respiratory rate, a slightly lower optimal pH, and failed to oxidize fructose, galactose, lactose, raffinose, and trehalose.
Some Biological Characteristics of Chlorotic Substrains of Euglena gracilis.*
Authors: GROSS J. A. , JAHN T. L. 
Published: May 2007

SYNOPSIS. It has been assumed by others that green euglenas and derived bleached forms are physiologically equivalent except for chlorophyll and plastids. Some workers, however, have remarked upon differences which might depend on the mode of bleaching.Several hitherto undescribed chlorotic substrains of E. gracilis var. bacillaris were examined for pigment alteration, growth under a variety of conditions, and ability to withstand high temperature. These studies indicated physiological variation in the different chlorotic substrains. Although all were apparently chlorophyll‐less and aplastidic, only one seemed completely achromatic. The carotenoid content of others varied. Metabolic changes manifested by altered pigmentation may reflect enzymatic variation caused by the chlorosis‐inducing agents.
Leaf Water Repellency as an Adaptation to Tropical Montane Cloud Forest Environments
Authors: Holder Curtis D. 
Published: May 2007

ABSTRACTAdaptations that reduce water retention on leaf surfaces may increase photosynthetic capacity of cloud forests because carbon dioxide diffuses slower in water than air. Leaf water repellency was examined in three distinct ecosystems to test the hypothesis that tropical montane cloud forest species have a higher degree of leaf water repellency than species from tropical dry forests and species from temperate foothills‐grassland vegetation. Leaf water repellency was measured by calculating the contact angle of the leaf surface and the line tangent to a water droplet through the point of contact on the adaxial and the abaxial surface. Leaf water repellency was significantly different between the three study areas. The hypothesis that leaf water repellency is higher in cloud forest species than tropical dry forests and temperate foothills‐grassland vegetation was not confirmed in this study. Leaf water repellency was lower for cloud forest species (adaxial surface = 50.8°; abaxial surface = 82.9°) than tropical dry forest species (adaxial surface = 74.5°; abaxial surface = 87.3°) and temperate foothills‐grassland species (adaxial surface = 77.6°; abaxial surface = 95.8°). The low values of leaf water repellency in cloud forest species may be influenced by presence of epiphylls and loss of epicuticular wax on the leaf surfaces.
Anabolic androgenic steroids induce micronuclei in buccal mucosa cells of bodybuilders
Authors: Torres-Bugarín O , Covarrubias-Bugarín R , Zamora-Perez A L , Torres-Mendoza B M G , García-Ulloa M , Martínez-Sandoval F G 
Published: May 2007

Objective:To evaluate genotoxicity of anabolic androgenic steroids (AAS) in male bodybuilders by a micronucleus assay in buccal mucosa cells.Methods:11 male bodybuilders volunteered to participate in this study and two groups were formed: group 1 (n = 6), without AAS consumption and group 2 (n = 5), with AAS consumption. A sample of buccal epithelium was taken from each participant once a week for 6 weeks. Samples were fixed, stained and analysed by a light microscope, and 2000 cells were counted from each slide. Results are expressed as micronucleated cells (MNC) per 1000 cells and were analysed by the Mann–Whitney U test and Wilcoxon’s test.Results:A marked increased in MNC was seen in bodybuilders with AAS consumption compared with those without AAS consumption (mean (SD) 4.1 (2.4) MNC/1000 cells vs 0.4 (0.4) MNC/1000 cells, respectively; p<0.004). Intragroup comparisons showed no differences in the MNC frequencies during the sampling time in group 1, whereas the MNC frequency in group 2 varied significantly, reaching the highest MNC frequencies in the third and fourth week of sampling (5.9 (2.4) MNC/1000 cells; 5.8 (1.8) MNC/1000 cells, respectively); frequency in the first sampled week was 1.1 (0.1) MNC/1000 cells. Significant differences in all sampled weeks were found between the two groups.Conclusion:AAS consumption increased the frequency of MNC from buccal mucosa in bodybuilders.
Airflow measurements in small animals
Authors: Marano Giuseppe 
Published: May 2007

Monitoring respiratory airflow is extremely important in pharmacological studies of the respiratory system. However, in mechanically ventilated small animals (e.g. rats and guinea pigs) the use of a commercial pneumotachometer, attached directly to the tracheal cannula, substantially increases the equipment dead space (the volume shared by inspired and expired gases). Since apparatus dead space must be added to the tidal volume (determined on the basis of ventilatory rate and animal body weight) necessary to meet the respiratory needs of the animal, the resulting stroke volume is greatly increased, specially in very small animals. This results in an increase in intrathoracic pressure which is potentially associated with a decrease in venous return, cardiac output, and arterial pressure. The author investigated the possibility of avoiding the potential problems of the added instrumental dead space by software-summing the separate flows measured on the inflation and deflation limbs of the breathing circuit. This study shows that the summation of the flow signals obtained from separate pneumotachometers on the inspiratory and expiratory arms of the breathing circuit is not dissimilar to the total flow as measured by a pneumotachometer directly attached to the tracheal cannula and that the method here described can be an advantageous alternative to the employment of a single pneumotachometer.
Reduction of animal use: experimental design and quality of experiments
Authors: Festing Michael F. W. 
Published: May 2007

Poorly designed and analysed experiments can lead to a waste of scientific resources, and may even reach the wrong conclusions. Surveys of published papers by a number of authors have shown that many experiments are poorly analysed statistically, and one survey suggested that about a third of experiments may be unnecessarily large. Few toxicologists attempted to control variability using blocking or covariance analysis. In this study experimental design and statistical methods in 3 papers published in toxicological journals were used as case studies and were examined in detail. The first used dogs to study the effects of ethanol on blood and hepatic parameters following chronic alcohol consumption in a 2 × 4 factorial experimental design. However, the authors used mongrel dogs of both sexes and different ages with a wide range of body weights without any attempt to control the variation. They had also attempted to analyse a factorial design using Student's t-test rather than the analysis of variance. Means of 2 blood parameters presented with one decimal place had apparently been rounded to the nearest 5 units. It is suggested that this experiment could equally well have been done in 3 blocks using 24 instead of 46 dogs. The second case study was an investigation of the response of 2 strains of mice to a toxic agent causing bladder injury. The first experiment involved 40 treatment combinations (2 strains × 4 doses × 5 days) with 3-6 mice per combination. There was no explanation of how the experiment involving approximately 180 mice had actually been done, but unequal subclass numbers suggest that the experiment may have been done on an ad hoc basis rather than being properly designed. It is suggested that the experiment could have been done as 2 blocks involving 80 instead of about 180 mice. The third study again involved a factorial design with 4 dose levels of a compound and 2 sexes, with a total of 80 mice. Open field behaviour was examined. The author incorrectly used the t-test to analyse the data, and concluded that there was no dose effect, when a correct analysis showed this to be highly significant. In all case studies the scientists presented means α standard deviations or standard errors involving only the animals contributing to that mean, rather than the much better estimates that would be obtained with a pooled estimate of error. This is virtually a universal practice. While it is not in itself a serious error, it may lead scientists to design experiments with group sizes of at least 3 animals, which may result in an unnecessarily large experiment if there are many treatment combinations. In conclusion, all 3 papers could have been substantially improved, with higher precision and the use of fewer animals if more attention had been paid to better experimental design.