The origins of American resource abundance

American manufacturing exports became increasingly resource-intensive over the very period, roughly 1880-1920, during which the U.S. ascended to the position of world leadership in manufacturing. This paper challenges the simplistic view that the resource-intensity of manufacturing reflected the country''s abundant geological endowment of mineral deposits. Instead, it shows that in the century following 1850 the U.S. exploited its natural resource potentials to a far greater extent than other countries and did so across virtually the entire range of industrial minerals. It argues that "natural resource abundance" was an endogenous. "socially constructed" condition that was not geologically pre-ordained. It examines the complex legal, institutional, technological and organizational adaptations that shaped the U.S. supply-responses to the expanding domestic and international industrial demands for minerals and mineral-products. It suggests that the existence of strong "positive feedbacks"--even in the exploitation of depletable resources--was responsible for the explosive growth of the American minerals economy.economic development an growth ;

Early Twentieth Century Productivity Growth Dynamics: An Inquiry into the Economic History of “Our Ignorance”

A marked acceleration of total factor productivity (TFP) growth in U.S. manufacturing followed World War I. This development contributed substantially to the absolute and relative rise of the domestic economy's aggregate TFP residual, which is observed when the 'growth accounts' for the first quarter of the twentieth century are compared with those for the second half of the nineteenth century. Two visions of the dynamics of productivity growth are germane to an understanding of these developments. One emphasizes the role of forces affecting broad sections of the economy, through spillovers of knowledge and the diffusion of general purpose technologies (GPT's). The second view considers that possible sources of productivity increase are multiple and idiosyncratic. Setting aside possible measurement errors, the latter approach regards sectoral and economy-wide surges of the TFP growth to be simply the result of which carried more weight than others. Although there is room for both views in an analysis of the sources of the industrial TFP acceleration during the 1920's, we find the evidence more compelling in support of the first approach. The proximate source of the TFP surge lay in the switch from declining or stable capital productivity to a rising output-capital ratio, which occurred at this time in many branches of manufacturing, and which was not accompanied by slowed growth in labor productivity. The 1920's saw critical advances in the electrification industry, the diffusion of a GTP that brought significant fixed capital-savings. But the same era also witnessed profound transformations in the American industrial labor market, followed the stoppage of mass immigration from Europe; rising real wages provided strong impetus to changes in workforce recruitment and management practices that were underway in some branches of the economy before the War. The productivity surge reflected the confluence of these two forces. This historical study has direct relevance for policies intended to increase the rate of productivity growth. In many respects, the decade of the 1920's launched the US economy on a high-growth path that lasted until the 1970's. If we hope to return to the growth performance of that era, we would be well advised to understand how it began.

General Purpose Technologies and Productivity Surges: Historical Reflections on the Future of the ICT Revolution

Presented to the International Symposium on ECONOMIC CHALLENGES OF THE 21ST CENTURY IN HISTORICAL PERSPECTIVE, Oxford, England, 2nd-4th July, 1999 Celebrating the Scholarly Career of Charles H. Feinstein, FBA. Re- examination of early twentieth century American productivity growth experience sheds light on the general phenomenon of recurring prolonged swings in total factor productivity (TFP) growth rate experienced in the advanced industrial economies. After a “productivity slowdown” lasting more than a quarter of a century (during which TFP for in the manufacturing sector grew at less than 1 percent per annum, industrial TFP surged to average 6 percent per annum during 1919-29. This contributed substantially to the absolute and relative rise of the US domestic economy’s TFP residual, and in many respects it may be seen as the opening of the high-growth era that persisted into the 1970s. The productivity surge marked the culminating phase in the diffusion of “the dynamo” as a general purpose technology (GPT); that saw a shift in the underlying technological regime brought about by the implementation of critical engineering and organizational advances originating in some two decades earlier. Closer analysis reveals the significant concurrence of the factory electrification movement in this period with important structural changes that were taking place in US labor markets; in addition, there were significant complementarities between managerial and organizational innovations and the new dynamo-based factory technology, on the one hand, and, and the reinforcement of both kinds of innovation by the macroeconomic conditions of the 1920s. This more complicated, historical view of the dynamics of GPT diffusion is supported by comparisons of the US experience of factory electrification with the developments taking place in Japanese industry during the 1920’s, and in the UK manufacturing sector during the 1930’s. Concluding sections of the paper reflect on the analogies and contrasts between the historical case of a socio-economic regime transition involving the electric dynamo and the modern experience of the information and communications technology (ICT) revolution. Our formulation the GPT concept in explicitly historical terms contributes to explaining the paradoxical phenomenon of the late twentieth century productivity slowdown in the US. It also points to some contemporary portents of a future phase of more rapid ICT-based growth in total factor productivity.

Dependence of Nebular Heavy-Element Abundance on H I Content for Spiral Galaxies

We analyze the galactic H I content and nebular log(O/H) for 60 spiral galaxies in the Moustakas et al. (2006) spectral catalog. After correcting for the mass-metallicity relationship, we show that the spirals in cluster environments show a positive correlation for log(O/H) on DEF, the galactic H I deficiency parameter, extending the results of previous analyses of the Virgo and Pegasus I clusters. Additionally, we show for the first time that galaxies in the field obey a similar dependence. The observed relationship between H I deficiency and galactic metallicity resembles similar trends shown by cosmological simulations of galaxy formation including inflows and outflows. These results indicate the previously observed metallicity-DEF correlation has a more universal interpretation than simply a cluster's effects on its member galaxies. Rather, we observe in all environments the stochastic effects of metal-poor infall as minor mergers and accretion help to build giant spirals.Comment: Accepted for publication in Ap

Platelet-mediated metabolism of the common dietary flavonoid, quercetin.

BACKGROUND: Flavonoid metabolites remain in blood for periods of time potentially long enough to allow interactions with cellular components of this tissue. It is well-established that flavonoids are metabolised within the intestine and liver into methylated, sulphated and glucuronidated counterparts, which inhibit platelet function. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrate evidence suggesting platelets which contain metabolic enzymes, as an alternative location for flavonoid metabolism. Quercetin and a plasma metabolite of this compound, 4'-O-methyl quercetin (tamarixetin) were shown to gain access to the cytosolic compartment of platelets, using confocal microscopy. High performance liquid chromatography (HPLC) and mass spectrometry (MS) showed that quercetin was transformed into a compound with a mass identical to tamarixetin, suggesting that the flavonoid was methylated by catechol-O-methyl transferase (COMT) within platelets. CONCLUSIONS/SIGNIFICANCE: Platelets potentially mediate a third phase of flavonoid metabolism, which may impact on the regulation of the function of these cells by metabolites of these dietary compounds

Evidence for a Molecular Cloud Origin for Gamma-Ray Bursts: Implications for the Nature of Star Formation in the Universe

It appears that the majority of rapidly-, well-localized gamma-ray bursts with undetected, or dark, optical afterglows, or `dark bursts' for short, occur in clouds of size R > 10L_{49}^{1/2} pc and mass M > 3x10^5L_{49} M_{sun}, where L is the isotropic-equivalent peak luminosity of the optical flash. We show that clouds of this size and mass cannot be modeled as a gas that is bound by pressure equilibrium with a warm or hot phase of the interstellar medium (i.e., a diffuse cloud): Such a cloud would be unstable to gravitational collapse, resulting in the collapse and fragmentation of the cloud until a burst of star formation re-establishes pressure equilibrium within the fragments, and the fragments are bound by self-gravity (i.e., a molecular cloud). Consequently, dark bursts probably occur in molecular clouds, in which case dark bursts are probably a byproduct of this burst of star formation if the molecular cloud formed recently, and/or the result of lingering or latter generation star formation if the molecular cloud formed some time ago. We then show that if bursts occur in Galactic-like molecular clouds, the column densities of which might be universal, the number of dark bursts can be comparable to the number of bursts with detected optical afterglows: This is what is observed, which suggests that the bursts with detected optical afterglows might also occur in molecular clouds. We confirm this by modeling and constraining the distribution of column densities, measured from absorption of the X-ray afterglow, of the bursts with detected optical afterglows: We find that this distribution is consistent with the expectation for bursts that occur in molecular clouds, and is not consistent with the expectation for bursts that occur in diffuse clouds. More...Comment: Accepted to The Astrophysical Journal, 22 pages, 6 figures, LaTe

Determining the exit time distribution for a closed cyclic network

AbstractConsider a closed, N-node, cyclic network, where each node has an independent, exponential single server. Using lattice-Bessel functions, we can explicitly solve for the transition probabilities of events that occur prior to one of the nodes becoming empty. This calculation entails associating with this absorbing process a symmetry group that is the semidirect product of simpler groups. As a byproduct, we are able to compute explicitly the entire spectrum for the finite-dimensional matrix generator of this process. When the number of nodes exceeds 1, such a spectrum is no longer purely real. Moreover, we are also able to obtain the quasistationary distribution or the limiting behavior of the network conditioned on no node ever being idle

A retrosynthetic co-templating method for the preparation of silicoaluminophosphate molecular sieves

This work has been supported by Johnson Matthey PLC, UK. Solid-state NMR spectra were obtained at the EPSRC UK National Solid-state NMR Service at Durham.A retrosynthetic method has been developed to design the synthesis of target zeotypes whose frameworks belong to the ABC-6 structural family and which contain gme cages. This permits the preparation of silicoaluminophosphate versions of AFX (SAPO-56), SFW (STA- 18) and GME (STA-19) topology types. The method makes simultaneous use of two organic structure directing agents (SDAs) to promote the formation of structural features such as cages or channels of the target framework. Computational modelling was used to identify SDAs for gme and other cages or channels in the target structures. The trimethylammonium cation was found to be the most favourable SDA for the gme cage while bisdiazabicyclooctane (DABCO) alkane cations and quaternary ammonium oligomers of DABCO with connecting polymethylene chain lengths of 4 to 8 methylene units acted as 1 templates for the additional cages or channels, respectively. The incorporation of each of the co-SDAs in the as-prepared materials was confirmed by chemical analysis, 13C MAS NMR and Rietveld refinement combined with computational modeling. Calcination of the SAPO- 56, STA-18 and some of the STA-19 materials gives microporous, fully tetrahedrally- coordinated framework solids with AFX, SFW and GME topologies: other STA-19 samples convert topotactically to SAPO-5. These results show that SAPOs in the ABC-6 family can be prepared via a targeted co-templating approach.PostprintPostprintPeer reviewe

Fourteen New Companions from the Keck & Lick Radial Velocity Survey Including Five Brown Dwarf Candidates

We present radial velocities for 14 stars on the California & Carnegie Planet Search target list that reveal new companions. One star, HD 167665, was fit with a definitive Keplerian orbit leading to a minimum mass for the companion of 50.3 Mjup at a separation from its host of ~5.5 AU. Incomplete or limited phase coverage for the remaining 13 stars prevents us from assigning to them unique orbital parameters. Instead, we fit their radial velocities with Keplerian orbits across a grid of fixed values for Msini and period, P, and use the resulting reduced chi-square surface to place constraints on Msini, P, and semimajor axis, a. This technique allowed us to restrict Msini below the brown dwarf -- stellar mass boundary for an additional 4 companions (HD 150554, HD 8765, HD 72780, HD 74014). If the combined 5 companions are confirmed as brown dwarfs, these results would comprise the first major catch of such objects from our survey beyond ~3 AU.Comment: 29 pages, 14 figures, accepted to Ap

Facilitators and barriers to compliance with COVID-19 guidelines: a structural topic modelling analysis of free-text data from 17,500 UK adults

BACKGROUND: During the COVID-19 pandemic, the UK government implemented a series of guidelines, rules, and restrictions to change citizens' behaviour to tackle the spread of the virus, such as the promotion of face masks and the imposition of lockdown stay-at-home orders. The success of such measures requires active co-operation on the part of citizens, but compliance was not complete. Detailed research is required on the factors that aided or hindered compliance with these measures. METHODS: To understand the facilitators and barriers to compliance with COVID-19 guidelines, we used structural topic modelling, a text mining technique, to extract themes from over 26,000 free-text survey responses from 17,500 UK adults, collected between 17 November and 23 December 2020. RESULTS: The main factors facilitating compliance were desires to reduce risk to oneself and one's family and friends and to, a lesser extent, the general public. Also of importance were a desire to return to normality, the availability of activities and technological means to contact family and friends, and the ability to work from home. Identified barriers were difficulties maintaining social distancing in public (due to the actions of other people or environmental constraints), the need to provide or receive support from family and friends, social isolation, missing loved ones, and mental health impacts, perceiving the risks as low, social pressure to not comply, and difficulties understanding and keep abreast of changing rules. Several of the barriers and facilitators raised were related to participant characteristics. Notably, women were more likely to discuss needing to provide or receive mental health support from friends and family. CONCLUSION: The results demonstrated an array of factors contributed to compliance with guidelines. Of particular policy importance, the results suggest that government communication that emphasizes the potential risks of the virus and provides simple, consistent guidance on how to reduce the spread of the virus would improve compliance with preventive behaviours as COVID-19 continues and for future pandemics