bluuebunny/crossref_metadata_2025 huggingface dataset:
The Development of the National Money Market, 1893-1911
Authors: James John A.
Published: May 2010

In this article the convergence of U.S. interregional interest rates in the late nineteenth century is examined and two major hypotheses are tested in the framework of a bank portfolio selection model based on the capital-asset-pricing model. Both the spread of the commercial paper market and the lowering of entry barriers through the reduction of national bank minimum capital requirements are rejected as principal explanations. The erosion of local monopoly power is shown to have been of central importance, and this development was due to the growth of state rather than national banks.
The Post-Bellum Recovery of the South and the Cost of the Civil War
Authors: Temin Peter
Published: May 2010

In the last half of the nineteenth century the economy of the American South experienced three separate shocks which have been analyzed separately by different authors. This note synthesizes the literature and presents an integrated story in which the decline in the rate of growth of the demand for cotton (noted by Wright) and the results of emancipation on the southern labor supply (noted by Ransom and Sutch) had equal impacts on measured income in the post-bellum South. The Civil War itself had a much smaller and less lasting effect on southern income than Coldin and Lewis assumed; in the long run, it was the least important of the three shocks.
Nineteenth-Century Urbanization Patterns in the United States
Authors: Riefler Roger F.
Published: May 2010

Urbanization of the United States in the nineteenth century has been described in numerous scholarly texts. As Eric Lampard, writing in 1961, pointed out, “… the urban-industrial transformation [has] now become part of the furniture displayed in every up-to-date textbook of U.S. history.…” Yet, as the same author had pointed out six years earlier, at that time “no systematic study has ever been made of the role of cities in recent [as opposed to medieval] economic development. We are still unable to counter the charge that cities are ‘abnormal’ and ‘costly’ with any account of the ways in which they have actually facilitated, let alone fostered, progressive economic change.” Obviously, since 1955 significant progress has been made towards filling this lacuna.
A Price Index for Rural Massachusetts, 1750–1855
Authors: Rothenberg Winifred B.
Published: May 2010

Students of agricultural history, of pre-industrial labor productivity, of New England town histories, and, especially, of pre-1840 rates of economic growth have long needed a price index of Massachusetts farm prices for this period. The article presents two indexes, covering 15 farm products, weighted by their relative importance, first in 1800, then in 1855. Among the several issues raised by the behavior of farm prices between 1750 and 1855, one of the most interesting may be what this behavior reveals about the market imbeddedness of these farmers, particularly in view of the fact that the prices come, not from market quotations, but from farm account books.
World Demand for Cotton during the Nineteenth Century: Reply
Authors: Wright Gavin
Published: May 2010

Since writing “Cotton Competition,“ I have many times wished that I had never included the paragraph joining pages 632 and 633, since figures that were intended as no more than back-of-the-envelope confirmation of the econometric results have been cited as the central conclusions of the study. To make matters worse, the demand-shift formula was incorrectly applied, most seriously in the exaggerated decline in demand for American cotton between 1860 and 1870. For these reasons I am grateful to John Hanson for making these corrections and for giving me an opportunity to disown this particular halfdozen numbers.
Scots, Jews, and Subversives Among the Dismal Scientists
Authors: Grampp William D.
Published: May 2010

The most curious of the detractors of classical economics said it was the work of Scots, Jews, and subversives. The charges were meant to turn back the movement toward the free market, but there was some truth in them. Classical economics did begin in Scotland, Ricardo was Jewish, it was the policy of the Parliamentary Radicals, and it did threaten some major institutions. The paper describes how and to what effect these facts were used by men who each for his own reason did not like the market.
Urban Growth in the Mid-Atlantic States, 1785–1850
Authors: Crowther Simeon J.
Published: May 2010

This article analyzes aspects of secular urban growth in two systems of cities in the mid-Atlantic states. One system centers on New York City; the other on Philadelphia. The author finds that the growth oi New York's hinterland was an important factor in explaining that system's relatively rapid expansion through the War of 1812. In subsequent years, this situation changed; basing his analysis on cross-sectional data, the author shows that relatively simple patterns of development gave way to complex situations shaped by the differential impacts of transportation, manufacturing, and commerce on these two urban systems.
A Note on the Value of Colonial Exports of Shipping
Authors: Price Jacob M.
Published: May 2010

Aside from their studies of the iron industry, historians have given relatively little attention to the non-household manufacturing industries of colonial America—perhaps, many would say, for the very good reason that there was not much activity along these lines before the conjuncture of the American and the Industrial Revolutions. Yet there were manufactures that reached significant volumes for those times. One of these was the colonial shipbuilding industry which not only provided most of the vessels that carried North American commerce with the West Indies and the Old World but also provided the capital starved colonies with a significant export. In spite of its importance this trade has not received much attention from modern economic historians, including those who deal with the balance of payments. One reason is, perhaps, that the British government in the eighteenth century did not consider colonial built ships as foreign in any sense and did not regard their transfer to metropolitan ownership as “imports.” Thus the values of such transfers were not included in the Inspector-General's accounts of imports from the colonies nor were any other records kept of them, except for the ship-by-ship entries in the Registries of Shipping (which for the most part have not survived).
Child Labor and the Factory Acts
Authors: Nardinelli Clark
Published: May 2010

The industrial revolution transformed Great Britain from a nation of agricultural villages into a nation of factory towns. Many of the social changes accompanying industralization aroused the indignation of contemporary critics and later historians. Perhaps the most despised was the employment of children. Edward P. Thompson alleged “that the exploitation of little children, on this scale and with this intensity, was one of the most shameful events in our history.”
Labor Contracting in Turn-of-the-Century California Agriculture
Authors: Hallagan William S.
Published: May 2010

During the course of U.S. economic development, the institutions used to organize agricultural labor have undergone interesting and sometimes puzzling transformations. The transitions from wage contracting to tenancy observed in the post-bellum South and in nineteenth-century Iowa have been studied extensively.2 This paper evaluates the relatively neglected transition from wage labor to tenancy that occurred in the California fruit orchards during the period 1900–1910.3 Before 1903 Chinese and Japanese orchard workers were organized via the padrone system of wage labor, but in an abrupt series of events there ensued a shift into tenancy so dramatic that by 1909 contemporary observers noted that virtually all orchards were under tenant control. The fact that the new tenants were recent Japanese immigrants prompted investigations by the Immigration Commission as well as other agencies so that this particular shift into tenancy is documented in greater detail than those occurring in the South and in Iowa.
The Increasing Pay Gap for Women in the Textile and Clothing Industries, 1910 to 1970
Authors: McGouldrick Paul , Tannen Michael
Published: May 2010

This multiple regression study of male and female wages in the clothing and textile industries finds that the standardized pay gap has changed against women from 1910 to 1970. The cross-section study of wages in 1909-1910 finds a very small residual in favor of men; but when the English-speaking variable is interpreted as screening many able women (but not men) from manufacturing, the residual shifts to one slightly favoring women. The cross-section study of pay in substantially the same industry group during 1969 finds very substantial residuals in favor of men after standardizing earnings. Hypotheses suggested for explaining these contrary findings include a decline in women's investment in human capital relative to that of men, and changing government and union tax and benefit patterns that discriminate against female investment in human capital.
The Cost of World War II to the Soviet People: A Reply
Authors: Millar James R. , Linz Susan J.
Published: May 2010

Susan Linz and I are fascinated, if somewhat puzzled, by Edward Saraydar's comments on our research note “The Cost of World War II to the Soviet People” (this Journal, 38 [Dec. 1978]). His comment demonstrates what we ourselves discovered: that there are many ways to measure war costs. We are pleased to note that Saraydar apparently accepts the fundamental conception that we presented of the cost of the war to the population. We are also pleased to see that, despite his criticisms, the range we presented for the cost of the war (that is, 3.2 to 7.4 years' earnings of the 1940 Soviet labor force) stands up quite well as lower and upper bounds.
Market Power and Bank Lending: Some Evidence from Wisconsin, 1870–1900
Authors: Keehn Richard H.
Published: May 2010

The pioneering work of Lance Davis on regional bank loan rates in the United States from 1870 to 1914 generated several attempts to explain the observed regional interest rate differentials and their subsequent narrowing by 1914. This article reports on a more direct test of the hypothesis that barriers to capital mobility were due to monopoly power on the part of local bankers. Tests using data on individual banks and local markets for one state, Wisconsin, suggest that local competitive conditions did not exert a significant influence on bank lending performance. This may be the result of relatively free entry into Wisconsin banking during the period.
Monetary Reform, 1923–30: A Prelude to Colombia's Economic Development
Authors: Dalgaard Bruce R.
Published: May 2010

Two financial missions to Colombia headed by Edwin W. Kemmerer are examined to determine their impact on Colombia's financial system and on the flow of American investment to Colombia. The 1923 and 1930 missions established a central bank and completely reorganized the Colombian financial and fiscal system. These reforms served to provide enough stability to encourage American investment, which helped to develop a financial and economic infrastructure in Colombia.
Productivity Change and Grain Farm Practice on the Canadian Prairie, 1900–1930
Authors: Dick Trevor J. O.
Published: May 2010

This study constructs indexes of productivity change to show that the yield of prairie farm land fell, in some cases as much as 25 percent, while the productivity of non-land inputs rose 300 percent or more from 1900 to 1930. It was this latter productivity growth, rather than the supply of prairie wheat land emphasized by the “staples approach” to Canadian economic history, that made the western prairie profitable to farm, and that contributed most to expanding the supply of prairie wheat. Much of the post-World War I expansion of settlement was on the drier and relatively low yielding parts of the Canadian prairie.
The Diffusion of the New Husbandry in Northern France, 1815–1840
Authors: Grantham George W.
Published: May 2010

This article deals with agricultural innovation in early nineteenth-century France. The core of the argument advanced is that the diffusion of the new intensive mixed husbandry in northern France was delayed by the slow growth in demand for meat and dairy products before 1840, which reduced the advantages to be gained from adopting forage-intensive crop rotations. Because the climate of southern France precluded large-scale adoption of the northern varieties of mixed husbandry, this study confines itself to the part of France lying north of the Loire, and east of the Breton peninsula. This region contained 39 percent of France's people in 1840, raised 48 percent of its wheat and 64 percent of its fodder, and produced more than 75 percent of the value of its animal production. It was already the most industrialized and wealthy section of the country.
Marketing Methods in the International Steam Engine Market: The Case of Boulton and Watt
Authors: Tann Jennifer
Published: May 2010

James Watt patented his improved steam engine in 1769 but, as is well known, lacked the capital and other facilities to exploit the patent. It was not until the commencement of his partnership with Matthew Boulton in 1775, after Boulton had successfully obtained an Act of Parliament extending the patent to 1800, that the technical development and commercial exploitation of his engine could be effected. The first engines were all reciprocating ones operating pumping and, later, blowing machinery. But, partly in response to Boulton's insistence that demand for factory engines would escalate, Watt developed and in 1782 patented his rotative engine.
Taxation and Inequality in Uganda, 1900–1964
Authors: Jamal Vali
Published: May 2010

Amuch neglected topic in the economic history of Uganda is the contribution of fiscal policy to the inequality of income. While generalizations have been made about the heavy burden of taxation on Uganda's Africans and the bias in the distribution of government expenditure, no systematic analysis of these issues has been undertaken. It is my objective to rectify this shortcoming, and to provide estimates of the incidence of taxation on different races and sectors of the economy at different periods. This study should be of parallel interest to my earlier article, demonstrating the extent of inequality in Uganda, since it shows that the government's tax policy had a major effect on the distribution of income in the country. The present paper focuses particularly on the farmers, who have always been at the bottom of the distribution ladder, and attempts to answer the following questions. 1.) What were the major sources of tax revenue in Uganda, and what proportion of the revenue was derived from the farmers? 2.) What was the farmers' rate of taxation compared to that of other sections of the population? 3.) How was expenditure out of government revenue distributed?
Antebellum Southern White Fertility: A Demographic and Economic Analysis
Authors: Steckel Richard H.
Published: May 2010

This paper investigates the decline and regional differential in antebellum southern white fertility using published census materials and the 1860 population schedules. Demographic analysis is conducted with a synthetic total fertility rate that has four components: age at first birth, age at last surviving birth, surviving-child spacing, and the proportion of women who eventually have surviving children. The socioeconomic analysis employs regressions and focuses on causes of the underlying changes in the components. Family limitation appears to have been unimportant in this population. The distribution of wealth was.probably an important factor shaping the time trend and regional differential in fertility.
Jewish American Entrepreneurs
Authors: Sarachek Bernard
Published: May 2010

This note contrasts the familial origins of 136 Jewish American entrepreneurs with those of 187 American non-Jewish entrepreneurs described in a previous study of mine. Information on both groups was drawn from published biographies. In addition, manuscript biographies were used to gather information on Jewish entrepreneurs.
Nonlinear dynamics and synthetic-jet-based control of a canonical separated flow
Authors: KOTAPATI RUPESH B. , MITTAL RAJAT , MARXEN OLAF , HAM FRANK , YOU DONGHYUN , CATTAFESTA LOUIS N.
Published: May 2010

A novel flow configuration devised for investigation of active control of separated airfoil flows using synthetic jets is presented. The configuration consists of a flat plate, with an elliptic leading edge and a blunt trailing edge, at zero incidence in a free stream. Flow separation is induced on the upper surface of the airfoil at the aft-chord location by applying suction and blowing on the top boundary of the computational domain. Typical separated airfoil flows are generally characterized by at least three distinct frequency scales corresponding to the shear layer instability, the unsteadiness of the separated region and the vortex shedding in the wake, and all these features are present in the current flow. Two-dimensional Navier–Stokes simulations of this flow at a chord Reynolds number of 6 × 104 have been carried out to examine the nonlinear dynamics in this flow and its implications for synthetic-jet-based separation control. The results show that there is a strong nonlinear coupling between the various features of the flow, and that the uncontrolled as well as the forced flow is characterized by a variety of ‘lock-on’ states that result from this nonlinear coupling. The most effective separation control is found to occur at the highest forcing frequency for which both the shear layer and the separated region lock on to the forcing frequency. The effects of the Reynolds number on the scaling of the characteristic frequencies of the separated flow and its subsequent control are studied by repeating some of the simulations at a higher Reynolds number of 1 × 105.
Fully nonlinear higher-order model equations for long internal waves in a two-fluid system
Authors: DEBSARMA SUMA , DAS K. P. , KIRBY JAMES T.
Published: May 2010

Fully nonlinear model equations, including dispersive effects at one-order higher approximation than in the model of Choi & Camassa (J. Fluid Mech., vol. 396, 1999, pp. 1–36), are derived for long internal waves propagating in two spatial horizontal dimensions in a two-fluid system, where the lower layer is of infinite depth. The model equations consist of two coupled equations for the displacement of the interface and the horizontal velocity of the upper layer at an arbitrary elevation, and they are correct to O(μ2) terms, where μ is the ratio of thickness of the upper-layer fluid to a typical wavelength. For solitary waves propagating in one horizontal direction, the two coupled equations reduce to a single equation for the elevation of the interface. Solitary wave profiles obtained numerically from this equation for different wave speeds are in good agreement with computational results based on Euler's equations. A numerical approach for the propagation of solitary waves is provided in the weakly nonlinear case.
The first African-American in Antarctica: George W. Gibbs Jr.
Authors: Stein Glenn M.
Published: May 2010

On 2 September 2009, the Advisory Committee on Antarctic Names (US Board on Geographic Names) confirmed a place name for George Washington Gibbs Jr, the first African-American expedition member to set foot on the Antarctic continent (Fig. 1). Gibbs Point forms the northwest entrance to Gaul Cove, on the northeast of Horseshoe Island, Marguerite Bay, Antarctic Peninsula (67°48′22″S, 67°09′38″W) (Fig. 2).
Evaluating an evolutionary method of design style imitation
Authors: Gómez de Silva Garza Andrés , Zamora Lores Arám
Published: May 2010

We propose a computational method for producing novel constructs that fall within an existing design or artistic style. The method is based on evolutionary algorithms, and we discuss related knowledge representation issues. We then present an implementation of this method that we used in order to imitate the style of the Dutch painter Mondrian. Finally, we explain and give the results of a cognitive experiment designed to determine the effectiveness of the method, and provide a discussion of these results.
Diagnosis and management of prostate cancer in the older man
Authors: McCracken SRC , Durkan GC , Pickard RS , Robson CN
Published: May 2010

Prostate cancer is the most common malignancy and the second leading cause of cancer death, in men, in western countries. Prostate cancer is diagnosed in very few people aged younger than 50 years (<0.1% of all patients). The mean age of patients with this disorder is 72–74 years. Most men aged older than 85 years have histological prostate cancer. Androgen deprivation reduces tumour activity in approximately 80% of patients with advanced disease, but most tumours relapse within 2 years to an incurable castrate-resistant state. Treatment options for patients with castrate-resistant prostate cancer are very limited and, even with toxic therapy, such as docetaxel, the life expectancy is only improved by a median of 2 months. Hence earlier diagnosis and improved treatments for prostate cancer are urgently required. Novel drugs, such as Abiratorone acetate and MDV-3100 have shown promise in pre-clinical and early clinical trials, and a number are now in phase III clinical trials, alone or in combination with docetaxel.
Age-related change in endothelial and microvessel function and therapeutic consequences
Authors: Strain W David , Elyas Salim , Gates Phillip E , Shore Angela C
Published: May 2010

As the absolute numbers and proportion of older adults increases across most of the developed world, a greater understanding of the aetiopathogenic mechanisms of the increased vascular risk and their therapeutic implications becomes essential to all clinicians assessing and managing the geriatric patient. The role of endothelial function and the microcirculation is increasingly recognized in the maintenance of adequate perfusion, and their dysfunction is thought to be an early and potentially reversible mechanism by which age acts to increase cardiovascular risk.

Here we review evidence that altered microvascular function appears before other recognized predictors of vascular disease, and progresses from childhood to late adult life, preceding fulminant atherosclerotic or arteriosclerotic disease. Low birth-weight babies have reduced endothelial function in skin microvessels at 3 months, and by age ten brachial artery endothelial function is reduced in comparison with normal birth-weight babies. In overweight/obese adolescent children with clustering of traditional cardiovascular disease risk factors, endothelial function is lower compared with normal weight children and this appears to persist into early adulthood. Adult ageing is associated with impaired microvessel endothelial function and an increase in capillary blood pressure, independent of brachial artery blood pressure. Biological and lifestyle factors that influence microvessel function include body fat and visceral adiposity, sex hormone status, diet and physical activity.

Exploration of the therapeutic implications for management of endothelial dysfunction remains in embryonic state. The use of ACE-inhibitors, angiotensin receptor blockers and direct renin inhibitors in patients with evidence of microvascular damage such as retinopathy and microalbuminuria has been established; however, in the general older population the benefit has yet to be established. Therefore current recommendations are to screen for microvascular damage and if present target treatments after control of other vascular risk factors such as hypertension.
ADAM SMITH’S SYSTEM OF NATURAL LIBERTY: COMPETITION, CONTESTABILITY, AND MARKET PROCESS
Authors: BRADLEY MICHAEL E.
Published: May 2010

In this article, I argue that Adam Smith’s system of perfect liberty contains some of the seeds of perfect competition, but that the modern perfectly competitive model differs from Smith’s perfect liberty in some important respects—in particular, the role of active competition among firms and the role of the entrepreneur. The article examines the analytical linkages between Smith’s system of liberty and three strands of modern economic theory—neoclassical perfect competition, contestable market theory and the Austrian analysis of market process.
Local signalling environments and human male infertility: what we can learn from mouse models
Authors: Nalam Roopa L. , Matzuk Martin M.
Published: May 2010

Infertility is one of the most prevalent public health problems facing young adult males in today's society. A clear, treatable cause of infertility cannot be determined in a large number of these patients, and a growing body of evidence suggests that infertility in many of these men may be due to genetic causes. Studies using mouse knockout technology have been integral for examination of normal spermatogenesis and to identify proteins essential for this process, which in turn are candidate genes for human male infertility. Successful spermatogenesis depends on a delicate balance of local signalling factors, and this review focuses on the genes that encode these factors. Normal functioning of all testicular cell types is essential for fertility and might also be crucial to prevent germ cell oncogenesis. Analysis of these signalling processes in spermatogenesis using mouse models has provided investigators with an invaluable tool to effectively translate basic science research to the research of human disease and infertility.
Advances in magneto‐optical imaging applied to rock magnetism and paleomagnetism
Authors: Uehara Minoru , van der Beek Cornelis Jacominus , Gattacceca Jérôme , Skidanov Vladimir A. , Quesnel Yoann
Published: May 2010

We present results of the magneto‐optical imaging technique applied to rock samples. This technique measures the magnetic flux threading a magneto‐optically active film, which rotates the polarization direction of transmitted light (Faraday rotation) and is directly placed on the sample. Through the analyzer of a reflected light microscope, the vertical component of the surface magnetic field of the sample is observed and can be quantified through a specific calibration procedure. Owing to the thin magneto‐optically active film (5 μm) and the small sample‐to‐film distance (∼1 μm), stray fields produced by magnetic grains in rocks carrying saturation isothermal remanent magnetization are successfully imaged with a spatial resolution of 10 μm. We can also image the surface field distribution of rocks carrying natural remanent magnetizations by modulating the analyzer angle. In addition to its high spatial resolution, this technique offers a direct comparison between magnetic and reflected light images. Therefore, this new technique appears to be a powerful tool to map and identify the carriers of magnetic remanence in rock samples.
The future of hydrology: An evolving science for a changing world
Authors: Wagener Thorsten , Sivapalan Murugesu , Troch Peter A. , McGlynn Brian L. , Harman Ciaran J. , Gupta Hoshin V. , Kumar Praveen , Rao P. Suresh C. , Basu Nandita B. , Wilson Jennifer S.
Published: May 2010

Human activities exert global‐scale impacts on our environment with significant implications for freshwater‐driven services and hazards for humans and nature. Our approach to the science of hydrology needs to significantly change so that we can understand and predict these implications. Such an adjustment is a necessary prerequisite for the development of sustainable water resource management strategies and to achieve long‐term water security for people and the environment. Hydrology requires a paradigm shift in which predictions of system behavior that are beyond the range of previously observed variability or that result from significant alterations of physical (structural) system characteristics become the new norm. To achieve this shift, hydrologists must become both synthesists, observing and analyzing the system as a holistic entity, and analysts, understanding the functioning of individual system components, while operating firmly within a well‐designed hypothesis testing framework. Cross‐disciplinary integration must become a primary characteristic of hydrologic research, catalyzing new research and nurturing new educational models. The test of our quantitative understanding across atmosphere, hydrosphere, lithosphere, biosphere, and anthroposphere will necessarily lie in new approaches to benchmark our ability to predict the regional hydrologic and connected implications of environmental change. To address these challenges and to serve as a catalyst to bring about the necessary changes to hydrologic science, we call for a long‐term initiative to address the regional implications of environmental change.
A general lack of compensation for gene dosage in yeast
Authors: Springer Michael , Weissman Jonathan S , Kirschner Marc W
Published: May 2010

Gene copy number variation has been discovered in humans, between related species, and in different cancer tissues, but it is unclear how much of this genomic‐level variation leads to changes in the level of protein abundance. To address this, we eliminated one of the two genomic copies of 730 different genes in Saccharomyces cerevisiae and asked how often a 50% reduction in gene dosage leads to a 50% reduction in protein level. For at least 80% of genes tested, and under several environmental conditions, it does: protein levels in the heterozygous strain are close to 50% of wild type. For <5% of the genes tested, the protein levels in the heterozygote are maintained at nearly wild‐type levels. These experiments show that protein levels are not, in general, directly monitored and adjusted to a desired level. Combined with fitness data, this implies that proteins are expressed at levels higher than necessary for survival.
Divergence of nucleosome positioning between two closely related yeast species: genetic basis and functional consequences
Authors: Tirosh Itay , Sigal Nadejda , Barkai Naama
Published: May 2010

Gene regulation differs greatly between related species, constituting a major source of phenotypic diversity. Recent studies characterized extensive differences in the gene expression programs of closely related species. In contrast, virtually nothing is known about the evolution of chromatin structure and how it influences the divergence of gene expression. Here, we compare the genome‐wide nucleosome positioning of two closely related yeast species and, by profiling their inter‐specific hybrid, trace the genetic basis of the observed differences into mutations affecting the local DNA sequences (cis effects) or the upstream regulators (trans effects). The majority (∼70%) of inter‐species differences is due to cis effects, leaving a significant contribution (30%) for trans factors. We show that cis effects are well explained by mutations in nucleosome‐disfavoring AT‐rich sequences, but are not associated with divergence of nucleosome‐favoring sequences. Differences in nucleosome positioning propagate to multiple adjacent nucleosomes, supporting the statistical positioning hypothesis, and we provide evidence that nucleosome‐free regions, but not the +1 nucleosome, serve as stable border elements. Surprisingly, although we find that differential nucleosome positioning among cell types is strongly correlated with differential expression, this does not seem to be the case for evolutionary changes: divergence of nucleosome positioning is excluded from regulatory elements and is not correlated with gene expression divergence, suggesting a primarily neutral mode of evolution. Our results provide evolutionary insights to the genetic determinants and regulatory function of nucleosome positioning.
Patterns of basal signaling heterogeneity can distinguish cellular populations with different drug sensitivities
Authors: Singh Dinesh Kumar , Ku Chin‐Jen , Wichaidit Chonlarat , Steininger Robert J , Wu Lani F , Altschuler Steven J
Published: May 2010

Phenotypic heterogeneity has been widely observed in cellular populations. However, the extent to which heterogeneity contains biologically or clinically important information is not well understood. Here, we investigated whether patterns of basal signaling heterogeneity, in untreated cancer cell populations, could distinguish cellular populations with different drug sensitivities. We modeled cellular heterogeneity as a mixture of stereotyped signaling states, identified based on colocalization patterns of activated signaling molecules from microscopy images. We found that patterns of heterogeneity could be used to separate the most sensitive and resistant populations to paclitaxel within a set of H460 lung cancer clones and within the NCI‐60 panel of cancer cell lines, but not for a set of less heterogeneous, immortalized noncancer human bronchial epithelial cell (HBEC) clones. Our results suggest that patterns of signaling heterogeneity, characterized as ensembles of a small number of distinct phenotypic states, can reveal functional differences among cellular populations.
Statistical Tests for Detecting Differential RNA-Transcript Expression from Read Counts
Authors: Stegle Oliver , Drewe Philipp , Bohnert Regina , Borgwardt Karsten , Rätsch Gunnar
Published: May 2010

As a fruit of the current revolution in sequencing technology, transcriptomes can now be analyzed at an unprecedented level of detail. These advances have been exploited for detecting differential expressed genes across biological samples and for quantifying the abundances of various RNA transcripts within one gene. However, explicit strategies for detecting the hidden differential abundances of RNA transcripts in biological samples have not been defined. In this work, we present two novel statistical tests to address this issue: a 'gene structure sensitive' Poisson test for detecting differential expression when the transcript structure of the gene is known, and a kernel-based test called Maximum Mean Discrepancy when it is unknown. We analyzed the proposed approaches on simulated read data for two artificial samples as well as on factual reads generated by the Illumina Genome Analyzer for two C. elegans samples. Our analysis shows that the Poisson test identifies genes with differential transcript expression considerably better that previously proposed RNA transcript quantification approaches for this task. The MMD test is able to detect a large fraction (75%) of such differential cases without the knowledge of the annotated transcripts. It is therefore well-suited to analyze RNA-Seq experiments when the genome annotations are incomplete or not available, where other approaches have to fail.
PMEM of carabid beetles in the agro-ecosystem: Prospects and problems
Authors: Priesnitz Kai , Benker Ullrich
Published: May 2010

The comparison of carabid communities sampled at three different field sites during 5 years of ecological biosafety research provides useful information for the design of a post market environmental monitoring of this arthropod family. Each evaluated field site demonstrated a unique composition of carabid species. A baseline for the carabid beetle communities would therefore be necessary for each field site to detect any changes in its composition over time. Aside from the influence of the location, the impacts of weather, the date of sampling and of course the chosen sampling method have to be considered. A standardized method is a basic requirement for a replicable assessment. The number of traps per square meter, and the size and the design of the traps have to be determined a priori. The influence of the weather has to be taken into account and only a monitoring over a longer time period may yield reliable data. Multiple samples taken subsequently during the growing season would minimize potential mistakes in the interpretation of data. However, the main problem implementing a PMEM with carabids considering the mentioned obstacles will be the long-term financing of such a project.
Long-term Benefits of GM crops: Potential for Diabrotica Suppression in Europe using Bt Maize
Authors: Storer Nicholas , Schlotter Peter , Steffey Kevin
Published: May 2010

Transgenic crops producing insecticidal proteins from Bacillus thuringiensis (Bt) have been widely adopted since 1996 in the United States of America to combat important pests of maize and cotton. There is growing evidence that several target pest populations have been dramatically reduced in areas where the Bt crops have been most intensively adopted over multiple years. The evidence is most dramatic for nonmigratory monophagous and oligophagous species that show high mortality on Bt crops, such as European corn borer (Ostrinia nubilalis), and tobacco budworm (Heliothis virescens). Bt cotton is currently being used in the southwestern USA as part of an area-wide eradication program for pink bollworm (Pectinophora gossypiella). Single, stacked, and pyramided Bt maize lines producing coleopteran-active insecticidal proteins have been shown in some cases to cause >99% mortality of western corn rootworm (Diabrotica virgifera virgifera) larvae every year. Simulation models suggest that long-term area-wide cultivation of these Bt corn lines can lead to dramatic population reduction, and even local extinction, of corn rootworms. An eradication program for this economically important pest, based around Bt maize and incorporating a combination of other tools, would benefit European agriculture and the environment. Post-commercial monitoring programs should be designed to investigate long-term benefits to agricultural production systems that can be reasonably expected from the widespread cultivation of Bt crops in Europe.
The 1973 Least-Squares Adjustment of the Fundamental Constants
Authors: Cohen E. Richard , Taylor B. N.
Published: May 2010

This paper is a summary of the 1973 least-squares adjustment of the fundamental physical constants carried out by the authors under the auspices of the CODATA Task Group on Fundamental Constants. The salient features of both the input data used and its detailed analysis by least-squares are given. Also included is the resulting set of best values of the constants which is to be recommended for international adoption by CODATA, a comparison of several of these values with those resulting from recent past adjustments, and a discussion of current problem areas in the fundamental constants field requiring additional research.
Water wave radiation by a heaving submerged horizontal disk very near the free surface
Authors: Farina Leandro
Published: May 2010

The radiation of water waves by heaving horizontal disk at a shallow submergence depth is considered. The problem is formulated as a Fredholm integral equation. The resonant frequencies originating from the shallow submergence are examined and their locations are computed by a modified Newton’s method. The hydrodynamic coefficients in a neighborhood of a resonance pole are found to be represented by circles in the complex plane. An asymptotic approximation is obtained for small values of the submergence depth. The relationship between the small-submergence first order problem and the dock problem is explored and found to be clearly represented by the added mass and damping coefficients.
Frequency-dependent viscous flow in channels with fractal rough surfaces
Authors: Cortis Andrea , Berryman James G.
Published: May 2010

The viscous dynamic permeability of some fractal-like channels is studied. For our particular class of geometries, the ratio of the pore surface area-to-volume tends to ∞ (but has a finite cutoff), and the universal scaling of the dynamic permeability, k(ω), needs modification. We performed accurate numerical computations of k(ω) for channels characterized by deterministic fractal wall surfaces, for a broad range of fractal dimensions. The pertinent scaling model for k(ω) introduces explicitly the fractal dimension of the wall surface for a range of frequencies across the transition between viscous and inertia dominated regimes. The new model provides excellent agreement with our numerical simulations.
Molecular double core hole electron spectroscopy for chemical analysis
Authors: Tashiro Motomichi , Ehara Masahiro , Fukuzawa Hironobu , Ueda Kiyoshi , Buth Christian , Kryzhevoi Nikolai V. , Cederbaum Lorenz S.
Published: May 2010

We explore the potential of double core hole electron spectroscopy for chemical analysis in terms of x-ray two-photon photoelectron spectroscopy. The creation of deep single and double core vacancies induces significant reorganization of valence electrons. The corresponding relaxation energies and the interatomic relaxation energies are evaluated by complete active space self-consistent field (CASSCF) calculations. We propose a method on how to experimentally extract these quantities by the measurement of single ionization potentials (IPs) and double core hole ionization potentials (DIPs). The influence of the chemical environment on these DIPs is also discussed for states with two holes at the same atomic site and states with two holes at two different atomic sites. Electron density difference between the ground and double core hole states clearly shows the relaxations accompanying the double core hole ionization. The effect is also compared to the sensitivity of single core hole IPs arising in single core hole electron spectroscopy. We have demonstrated the method for a representative set of small molecules LiF, BeO, BF, CO, N2, C2H2, C2H4, C2H6, CO2, and N2O. The scalar relativistic effect on IPs and on DIPs are briefly addressed.
Viability of using near infrared PbS quantum dots as active materials in luminescent solar concentrators
Authors: Shcherbatyuk G. V. , Inman R. H. , Wang C. , Winston R. , Ghosh S.
Published: May 2010

The performance of chemically synthesized lead sulfide (PbS) quantum dots (QDs) in planar, nontracking luminescent solar concentrators (LSCs) is evaluated using spectroscopic and photovoltaic techniques. Spatially resolved measurements are used to investigate and analyze the role of reduced self-absorption on the LSC efficiency. From comparative measurements of samples with Rhodamine B and CdSe/ZnS QDs it is established that PbS LSCs generate nearly twice the photocurrent in silicon cells than the other materials, achieving an integrated optical efficiency of 12.6%. This is attributed primarily to the broadband absorption of PbS which allows optimum harvesting of the solar spectrum.
Thermal shot noise in top-gated single carbon nanotube field effect transistors
Authors: Chaste J. , Pallecchi E. , Morfin P. , Fève G. , Kontos T. , Berroir J.-M. , Hakonen P. , Plaçais B.
Published: May 2010

The high-frequency transconductance and current noise of top-gated single carbon nanotube transistors have been measured and used to investigate hot electron effects in one-dimensional transistors. Results are in good agreement with a theory of one-dimensional nanotransistor. In particular the prediction of a large transconductance correction to the Johnson–Nyquist thermal noise formula is confirmed experimentally. Experiment shows that nanotube transistors can be used as fast charge detectors for quantum coherent electronics with a resolution of 13 μe/Hz in the 0.2–0.8 GHz band.
Electric-field-control of magnetic remanence of NiFe2O4 thin film epitaxially grown on Pb(Mg1/3Nb2/3)O3–PbTiO3
Authors: Park Jung Hwan , Jeong Young Kyu , Ryu Sangwoo , Son Jong Yeog , Jang Hyun Myung
Published: May 2010

We propose an asymmetric bilayer structure in which the magnetic remanence (MR) is controlled by the in-plane strain of the top NiFe2O4 (NFO) layer epitaxially constrained by the bottom Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) substrate. In this asymmetric structure, an electric-field-induced giant piezoelectric strain from the bottom PMN-PT layer is effectively transferred to the top NFO layer. We have shown that the room-temperature magnetic remanence (MR) of the 100-nm-thick NFO layer is enhanced by 46% when an electric-field-induced in-plane compressive strain is about −0.1%. Synchrotron x-ray absorption near edge structure study supports a scenario of the cation-charge redistribution between Ni2+ and Fe3+ ions under the condition of an electric-field-induced in-plane compressive strain.
Resistance switching of Cu/SiO2 memory cells studied under voltage and current-driven modes
Authors: Bernard Y. , Gonon P. , Jousseaume V.
Published: May 2010

Resistance switching in Cu/SiO2-based conductive-bridging random access memories is studied under voltage and current-driven modes. These two modes are used to study memory cycling and time-dependent switching. Voltage-current (V-I) cycles (logarithmic current ramp) are compared to I-V cycles (linear voltage ramp). The Off-On transition in V-I cycles is governed by device capacitance. The Off-On switching time (in the 10−1–103 s range) was studied under constant voltage and constant current stresses. The switching time varies as exp(V0/V) and as 1/I. Switching kinetics is discussed considering a Fowler–Nordheim tunneling injection law and a field-induced nucleation theory.
The effect of traps on the performance of graphene field-effect transistors
Authors: Zhu J. , Jhaveri R. , Woo J. C. S.
Published: May 2010

This paper studies the performance degradation of graphene field-effect transistors due to the presence of traps. The mobile charge modulation by gate voltage is degraded because of immobile trapped charges. As a result the current is reduced and the on/off ratio is decreased. Extracted mobility using transconductance method is shown to be underestimated considerably due to the effect of traps.
Ultrafast laser inscription of bistable and reversible waveguides in strontium barium niobate crystals
Authors: Jaque D. , Psaila N. D. , Thomson R. R. , Chen F. , Maestro L. M. , Ródenas A. , Reid D. T. , Kar A. K.
Published: May 2010

We report the fabrication of buried optical channel waveguides in strontium barium niobate nonlinear ferroelectric crystals by direct ultrafast laser inscription. These waveguides are strongly polarized and can be reversibly switched on and off by changing the temperature of the crystal, a characteristic we attribute to the bistable enhancement of the electro-optic coefficients at the ferro to paraelectric phase transition.
Water deficit and impaired pegging effects on peanut seed yield: links with water and photosynthetically active radiation use efficiencies
Authors: Haro Ricardo J. , Dardanelli Julio L. , Collino Daniel J. , Otegui María E.
Published: May 2010

Peanut (Arachis hypogaea L.) production is frequently affected by unpredictable events of water deficit during pod set, which modulate water use, water use efficiency for biomass production (WUEB), and biomass partitioning to seeds. We studied the effects of drought-induced impaired pegging on WUEB and the link between WUEB and photosynthetically active radiation use efficiency (PAR-UE). Field experiments were conducted that combined: two cultivars of contrasting pegging capacity (ASEM > Florman), two water regimes (irrigated and water stress) and different sowing dates. WUEB ranged between 6.1 and 6.7 g kPa/mm for irrigated plots, and between 2.9 and 7.1 g kPa/mm for water-stressed plots. WUE for pod production showed similar trends, but was larger for ASEM than for Florman because of higher biomass allocation to pods and pegging capacity of the former. The relationship between standardised values of WUEB and PAR-UE varied linearly for the post-R6 period, but fitted models differed between water regimes. This difference was attributed to the relative importance of stomata control on gas exchange (direct effects of water deficit) respect to feedback effects on photosynthesis caused by reproductive sink size (indirect effects of water deficit). Variation in post-R6 PAR-UE could be linked exclusively to the latter, but variation registered in WUEB acknowledged both controls.