198 research outputs found
Kentucky Terrain
The terrain of Kentucky has been shaped by geologic forces and the underlying rocks.Tectonic forces lifted, bent, and buckled the rocksāoriginally formed from sediments on shallow sea floors or swampy lowlands. Weathering and erosion shaved the hills and dissected the plains, exposing at the surface a cross section of rocks 250 to 500 million years old. The sands, gravels, silts, and clays of the Jackson Purchase Region are younger, remnants of a time when the sea lapped at the confluence of the Mississippi and Ohio Rivers.
The landforms in Kentucky are the result of the differential weathering of interbedded sandstones, siltstones, shales, and limestones. Sandstones and siltstones resist erosion, limestones dissolve along cracks and crevices, and shales break down quickly when exposed to air and water. Areas dominated by sandstones and siltstones tend to have hills with steep sides. As the shale content increases, the landscape becomes more rounded, with wide stream valleys. Areas underlain by limestone may have few surface streams (karst topography) and gently rolling land. As the shale content in the rocks increases relative to limestone, the land becomes hillier.
Natural resourcesācoal, oil, natural gas, soilsāare the products of geologic history and vary from region to region. In turn, the ecology and economy of the different regions of Kentucky are distinctive.
To learn more about the rocks and terrain typical of your area, find the region you live in on the map and then go to the associated text and picture group for that region (color-coded frame and header block matches the map region color)
Geologic Hazards in Kentucky
Geologic data were derived from the Kentucky Geological Survey-U.S. Geological Survey areal geologic mapping project. Nearly 190 geologists mapped the geology of Kentucky from 1960 to 1978. KGS geologists converted the resulting 707 geologic quadrangle maps into digital format at part of the STATEMAP component of the National Cooperative Geologic Mapping Program of the United States Geological Survey
Measuring the U.S. Employment Situation Using Online Panels: The Yale Labor Survey
This study presents the design and results of a rapid-ļ¬re survey that collects labor market data for individuals in the United States. The purpose is to test online panels for their application to social, economic, and demographic information as well as to apply this approach to the U.S. labor market. The Yale Labor Survey (YLS) used an online panel from YouGov to replicate statistics from the Current Population Survey (CPS), the governmentās oļ¬icial source of household labor market statistics. The YLSās advantages included its timeliness, low cost, and ability to develop new questions quickly to study unusual labor market patterns during the COVID-19 pandemic. Results from the YLS track employment data closely from the CPS during the pandemic. Although YLS estimates of unemployment and participation rates mirrored the broad trends in CPS data, YLS estimates of those two rates were less accurate than for employment. The study demonstrates the power of carefully crafted online surveys to replicate expensive traditional methods quickly and inexpensively
Simulation Study of Sulfonate Cluster Swelling in Ionomers
We have performed simulations to study how increasing humidity affects the
structure of Nafion-like ionomers under conditions of low sulfonate
concentration and low humidity. At the onset of membrane hydration, the
clusters split into smaller parts. These subsequently swell, but then maintain
constant the number of sulfonates per cluster. We find that the distribution of
water in low-sulfonate membranes depends strongly on the sulfonate
concentration. For a relatively low sulfonate concentration, nearly all the
side-chain terminal groups are within cluster formations, and the average water
loading per cluster matches the water content of membrane. However, for a
relatively higher sulfonate concentration the water-to-sulfonate ratio becomes
non-uniform. The clusters become wetter, while the inter-cluster bridges become
drier. We note the formation of unusual shells of water-rich material that
surround the sulfonate clusters.Comment: 24 pages, 15 figure
Fordism: a review essay
Fordism is a central concept in American labour history. This essay, the first survey of the range of historiographical and sociological approaches deployed to understand Fordism, suggests that Fordism and Americanism are inseparably intertwined. Previous scholarship has emphasised that the technological and managerial efficiency of Fordist practice were a hallmark of twentieth century Americanism. Historians of labour have demonstrated that these aspects manifested as a relentless system of control in the workplace that paradoxically helped to unify worker resistance. Historians of capitalism have tended to used Fordism to refer to an ethos underpinning mid-twentieth century capitalist development marked by a balance between mass production and mass consumption. They identify increased social provisions and class compromise between labour and management as features that made Fordism attractive to states rebuilding their economies following the Second World War. New transnational histories of Fordism have begun to bridge the gap between these two main interpretations to show how Fordist practice and ethos were exported together internationally as part of an ideological project to modernise nations in America's image. This essay concludes by assessing the usefulness of Fordism to historians and suggesting avenues for future research
Aspects of the political economy of development and synthetic biology
What implications might synthetic biologyās potential as a wholly new method of production have for the world economy, particularly developing countries? Theories of political economy predict that synthetic biology can shift terms of trade and displace producers in developing countries. Governments, however, retain the ability to mitigate negative changes through social safety nets and to foster adaptation to some changes through research, education and investment. We consider the effects the synthetic production of otherwise naturally derived molecules are likely to have on trade and investment, particularly in developing countries. Both rubber in Malaysia and indigo dyes in India provide historical examples of natural molecules that faced market dislocations from synthetic competitors. Natural rubber was able to maintain significant market share, while natural indigo vanished from world markets. These cases demonstrate the two extremes of the impact synthetic biology might have on naturally derived products. If developing countries can cushion the pain of technological changes by providing producers support as they retool or exit, the harmful effects of synthetic biology can be mitigated while its benefits can still be captured
Subtype-Selective Small Molecule Inhibitors Reveal a Fundamental Role for Nav1.7 in Nociceptor Electrogenesis, Axonal Conduction and Presynaptic Release.
Human genetic studies show that the voltage gated sodium channel 1.7 (Nav1.7) is a key molecular determinant of pain sensation. However, defining the Nav1.7 contribution to nociceptive signalling has been hampered by a lack of selective inhibitors. Here we report two potent and selective arylsulfonamide Nav1.7 inhibitors; PF-05198007 and PF-05089771, which we have used to directly interrogate Nav1.7's role in nociceptor physiology. We report that Nav1.7 is the predominant functional TTX-sensitive Nav in mouse and human nociceptors and contributes to the initiation and the upstroke phase of the nociceptor action potential. Moreover, we confirm a role for Nav1.7 in influencing synaptic transmission in the dorsal horn of the spinal cord as well as peripheral neuropeptide release in the skin. These findings demonstrate multiple contributions of Nav1.7 to nociceptor signalling and shed new light on the relative functional contribution of this channel to peripheral and central noxious signal transmission.The funder provided support in the form of
salaries for authors [AA, AB, MC, JT, MM, AW, EP,
AG, PJC, RD, DP, ZL, BM, CW, NS, RS, PS, NC, DK,
RB, ES], but did not have any additional role in the
study design, data collection and analysis, decision to
publish, or preparation of the manuscript. The specific
roles of these authors are articulated in the āauthor
contributionsā section
Theorizing media production: the poverty of political economy
This article argues that the Political Economy of Communication (PEC) has generally failed to develop theories of media production. Such theory as exists has been heavily influenced by accounts of mass production and flexible specialization in Hollywood. Hollywood film production has been viewed as paradigmatic of media production in general, in the same way as Ford was for manufacturing, and these theories continue to influence accounts of production across media and cultural industries. The article tests the mass production/flexible specialization paradigm against both the evidence of the Hollywood case and Fordās mass production system. An alternative paradigm, the theory of craft media production, is also examined. The article then attempts to show how applying organization theory and media economics can provide a more convincing explanation of media production and of the Hollywood case. Finally, the article briefly attempts to show how we might develop rich theoretical explanations of media production by exploring the relationships between economic, organizational and media-specific cultural elements
From Producer Innovation to User and Open Collaborative Innovation
In this paper we assess the economic viability of innovation by producers relative to two increasingly important alternative models: innovations by single user individuals or firms, and
open collaborative innovation. We analyze the design costs and architectures and
communication costs associated with each model. We conclude that both innovation by
individual users and open collaborative innovation increasingly compete with and may
displace producer innovation in many parts of the economy. We explain why this represents a paradigm shift with respect to innovation research, policymaking, and practice. We discuss
important implications and offer suggestions for further research
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