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This lecture discusses the work by the Estonian economist Ragnar Nurkse (1907-1959). It focuses on the early Nurkse, who was concerned with exchange rates, capital flows and what today we call the international financial architecture. It asks how many of the conclusions of International Currency Experience [Nurkse, R. (1944). International Currency Experience. Geneva: League of Nations.] survive. How many of Nurkse's points about the interwar gold standard are confirmed by subsequent scholarship? How many of his points are still relevant to the international monetary problems of today?

Oxidative addition and reductive elimination are the central steps in new palladium-catalyzed chemistry that forms C–N and C–O bonds in arylamines and ethers. In the potential mechanism shown on the right the amine is formed by reductive elimination from a four-coordinate, 16-electron amido aryl complex. The use of a chelating ligand such as 1,1′-bis(diphenylphosphanyl)ferrocene (DPPF) reduces the occurrence of the competing β-hydrogen elimination. X=Br, I; R, R′=alkyl, aryl.

The Whitehorse Group and Quartermaster Formation are extensive red-bed terrestrial sequences representing the final episode of sedimentation in the Palo Duro Basin in north-central Texas, U.S.A. Regionally, these strata record the culmination of a long-term regression sequence beginning in the middle to late Permian. The Whitehorse Group includes beds of abundant laminated to massive red quartz siltstone to fine sandstone and rare dolomite, laminated to massive gypsum, and claystones, as well as diagenetic gypsum. The Quartermaster Formation exhibits a change from nearly equal amounts of thin planar and lenticular fine sandstone and laminated to massive mudstone in its lower half to overlying strata with coarser-grained, cross-bedded sandstones indicative of meandering channels up to 7 m deep and rare overbank mudstones. Paleosols are absent in the Upper Whitehorse Group and only poorly developed in the Quartermaster Formation. Volcanic ash-fall deposits (tuffs) present in uppermost Whitehorse Group and lower Quartermaster Formation strata permit correlation among five stratigraphic sections distributed over ∼150 km and provide geochronologic age information for these rocks. Both the Whitehorse Group and Quartermaster Formation have traditionally been assigned to the late Permian Ochoan (Changhsingian) stage, and workers assumed that the Permian-Triassic boundary is characterized by a regionally significant unconformity. Chemostratigraphic or biostratigraphic evidence for this age assignment, however, have been lacking to date. Single zircon U-Pb CA-TIMS analyses from at least two distinct volcanic ash fall layers in the lower Quartermaster Formation, which were identified and collected from five different localities across the Palo Duro Basin, yield interpreted depositional ages ranging from 252.19 ± 0.30 to 251.74 ± 0.28 Ma. Single zircon U-Pb CA-TIMS analyses of detrital zircons from sandstones located only a few meters beneath the top of the Quartermaster Formation yield a range of dates from Mesoproterozoic (1418 Ma) to Middle Triassic (244.5 Ma; Anisian), the latter of which is interpreted as a maximum depositional age, which is no older than Anisian, thus indicating the Permian-Triassic boundary to lie somewhere within the lower Quartermaster Formation/upper Whitehorse Group succession. Stable carbon isotope data from 180 samples of early-burial dolomicrite cements preserve a chemostratigraphic signal that is similar among sections, with a large ∼−8‰ negative isotope excursion ∼20 m beneath the Whitehorse Group-Quartermaster Formation boundary. This large negative carbon isotope excursion is interpreted to be the same excursion associated with the end-Permian extinction and this is in concert with the new high precision radioisotopic age data presented and the fact that the excursion lies within a normal polarity stratigraphic magnetozone. Dolomite cement δ 13 C values remain less negative (between about −5 and −8 permil) into the lower part of the Quartermaster Formation before becoming more positive toward the top of the section. This long interval of negative δ 13 C values in the Quartermaster Formation is interpreted to represent the earliest Triassic (Induan) inception of biotic and ecosystem “recovery.” Oxygen isotope values of dolomicrite cements show a progressive trend toward more positive values through the boundary interval, suggesting substantially warmer conditions around the end-Permian extinction event and a trend toward cooler conditions after the earliest Triassic. Our observations on these strata show that the paleoenvironment and paleoclimate across the Permian-Triassic boundary in western, sub-equatorial Pangea was characterized by depositional systems that were not conducive to plant preservation.

Urinary bladder cystitis occurs in patients receiving radiation therapy for pelvic tumors. Radiation-induced formation of superoxide radicals is believed to damage the urothelium, exposing the underlying bladder smooth muscle to urine, culminating in nerve irritation and muscle dysfunction. We tested whether overexpression of MnSOD could decrease superoxide levels and protect the bladder from radiation damage. Pelvic irradiation led to sloughing of urothelial umbrella cells, with decreased transepithelial resistance, increased water and urea permeabilities, and increased expression of inducible nitric oxide synthase. Six months after irradiation, cystometrograms showed elevated intravesical pressures and prolonged voiding patterns. However, urothelia transfected with the MnSOD transgene recovered from radiation injury more rapidly, and detrusor function was much closer to that of control bladders than irradiated bladders without the transgene. We conclude that MnSOD gene therapy is protective, which could lead to its use in mitigating radiation cystitis and preventing dysfunction of the urinary bladder.

Using first-principles calculations, we investigate the surface energies, equilibrium morphology, and surface redox potentials for in the olivine structure. Low-energy surfaces are found in the [100], [010], [011], [101], [201], and [301] directions of the orthorhombic structure. With the calculated surface energies, we provide the thermodynamic equilibrium shape for the crystal through a Wulff construction. The dominating surfaces in the Wulff shape are (010), (011), and (201). Most of the surfaces in the Wulff shape have lower Li extraction potentials than the bulk, except for the (100) and (011) surfaces.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTRole of Electronic Structure in the Susceptibility of Metastable Transition-Metal Oxide Structures to TransformationJohn Reed and Gerbrand CederView Author Information Department of Materials Science and Engineering, Massachusetts Institute of Technology, Building 13-5056, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139 Cite this: Chem. Rev. 2004, 104, 10, 4513–4534Publication Date (Web):September 28, 2004Publication History Received1 March 2004Published online28 September 2004Published inissue 1 October 2004https://pubs.acs.org/doi/10.1021/cr020733xhttps://doi.org/10.1021/cr020733xresearch-articleACS PublicationsCopyright © 2004 American Chemical SocietyRequest reuse permissionsArticle Views7377Altmetric-Citations305LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Chemical structure,Energy,Ions,Oxides,Transition metals Get e-Alerts

Este ensayo analiza las explicaciones en pugna del patrón de desequilibrios globales y la magnitud del déficit externo norteamericano. Aquí se sostiene que, lejos de ser incompatibles, las explicaciones propuestas son parte de una historia más grande. La caída de la tasa de ahorro de Estados Unidos ha desempeñado un papel importante en el advenimiento de los desequilibrios de EE. UU. y el mundo. Al mismo tiempo, tendencias favorables de productividad convirtieron a EE. UU. en un buen lugar para invertir, atrayendo el ahorro externo que ayuda a financiar la inversión norteamericana y su cuenta corriente. El exceso de ahorro global es un factor que también cuenta, en tanto respalda los flujos de capital hacia EE. UU. y la inversión en EE. UU. Por último, la visión de la codependencia sino-norteamericana subraya el nivel de satisfacción de los países asiáticos con una situación en la que la demanda de exportaciones es desproporcionadamente importante en relación con la demanda doméstica (debido a una combinación de elevada aversión al riesgo después de la crisis de 1997-98 y su compromiso continuo con el crecimiento liderado por las exportaciones), una posición que se sostiene mediante tipos de cambio subvaluados y se refleja en el acelerado crecimiento de las importaciones de EE. UU. Clasificación JEL: F42 ; F44 ; G01

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAlkyl, aryl, hydrido, and acetate complexes of (DMPM)2Ru [DMPM = bis(dimethylphosphino)methane]: reductive elimination and oxidative addition of carbon-hydrogen bondsJohn F. Hartwig, Richard A. Andersen, and Robert G. BergmanCite this: Organometallics 1991, 10, 6, 1710–1719Publication Date (Print):June 1, 1991Publication History Published online1 May 2002Published inissue 1 June 1991https://doi.org/10.1021/om00052a016RIGHTS & PERMISSIONSArticle Views352Altmetric-Citations26LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (1 MB) Get e-Alerts Get e-Alerts