4,378 research outputs found
Twenty-first century atmospheric change and deforestation: potential impacts on tropical forests
No full textIntramolecular allylboration of γ-(ω-formylalkoxy)allylboronates for syntheses of trans- or cis-2-(ethenyl)tetrahydropyran-3-ol and 2-(ethenyl)oxepan-3-ol
No full text3-Alkoxy-1-alkynes 4 were hydroborated with pinacolborane (HBpin) to give 3-alkoxy-1-alkenylboronates 5. The latter gave (E)-3-alkoxyallylboronates (8: (E)-(MeO)2CHCH2(CH2)nCH2OCH=CHCH2Bpin, n=1–3) when they were subjected to iridium-catalyzed isomerization of the double bond. The corresponding (Z)-isomers 10 were synthesized by nickel-catalyzed isomerization of 5. Both allylboronates underwent intramolecular allylboration leading to the formation of trans-2-(ethenyl)tetrahydropyran-3-ol or 2-(ethenyl)oxepan-3-ol from 8 and the corresponding cis-isomers from 10 in the presence of Yb(OTf)3 (20 mol%) in aqueous acetonitrile at 90°C
Unemployment and Inflation Persistence in Spain: Are There Phillips Trade-Offs?
No full textThis paper studies the dynamic behavior of inflation and unemployment in Spain during the period 1964?1997. In particular, we analyze the implications of high persistence in both unemployment and inflation dynamics for inference regarding the size of Phillips trade-offs and sacrifice ratios in the Spanish economy, in response to a demand shock. To do so we use a Stuctural VAR approach with several identification outlines which give rise to alternative interpretations of the joint unemployment-inflation dynamics. When using a bivariate VAR we cannot reject the existence of a permanent output loss of one-half of one percentage point for each percentage point of permanent disinflation. However, when the VAR is augmented with a third variable, in order to disentangle monetary from non-monetary shocks within the demand class, the evidence favours a lower and marginally permanent trade-off with an output loss of about one-fourth of one percentage point.Publicad
Recent Changes in Amazon Forest Biomass and Dynamics
No full textRAINFOR has led field-based monitoring of forests across Amazonia since the turn of the millenium, and incorporated colleagues work since 1980. This unique long-term, large-scale perspective has yielded many surprising findings. Even far from the impacts of deforestation and degradation, the remote Amazon forests are changing. They have gained biomass, trees are growing faster, and they are dying faster. These changes are affected by climate change, and the accelerating carbon fluxes are themselves feeding back on the rate of global climate change. Neither has biodiversity been untouched by these changes. As an Amazon nation, Peru is a key part of this fascinating story which shows the unique ability of long-term, science-based monitoring to reveal how our world is changing
Agricultural trade liberalization in the Uruguay Round : one step forward, one step back?
No full textAfter evaluating the Uruguay Round's impact on agriculture and border protection in the next decade, the author concludes that while there was significant reform of the rules - particularly the conversion of nontariff barriers into tariffs and the reduction and binding of all tariffs - in practice, trade will probably be liberalized less than expected. The objective of the Round was to reverse protectionism and remove trade distortions. This may not be achieved in practice, at least not until further reductions are carried out in future rounds of negotiations. The major exception to this conclusion is in high-income Asian countries, where protection for major commodities will be significantly reduced. The tariffication and binding of all tariffs on agricultural products represents a significant step forward. Liberalization is implicit because countries are prohhibited from arbitrarily raising tariffs to new higher levels. But many of the newly established tariffs are so high in many countries as to effectively prohibit trade. Patterns of liberalization vary considerably by commodity and by country. Generally, the extent of liberalization was diminished by binding tariffs to the base period of 1986-88, when border protection was at a high point. In most OECD countries, this was worsened by"dirty tariffication:"the new base tariffs offered even greater protection than the nontariff barriers they replaced. Even after the commitments to tariff reductions in the Round, the ad valorem measure of the final binding tariffs will remain higher than the average rate of protection in 1982-93. A number of developing countries in East Asia, Latin America, and the Middle East chose to lock in prior liberalization efforts on some products. But for most commodities, there will be little actual liberalization, since most developing countries chose to bind their tariffs at a maximum level. Even when countries reduced already-bound rates, bound tariffs remained significantly higher than current applied rates, giving countries the flexibility to raise tariffs later. The high level of bound tariffs may allow countries to apply variable tariffs below the bound level, thus failing to stabilize tariffs and improve market access. Moreover, the Round did not touch many of the worst distortions in developing countries, such as import subsidies, export taxes, state-trading monopolies, and domestic policies that implicitly tax agriculture.Trade Policy,Environmental Economics&Policies,Economic Theory&Research,Export Competitiveness,Rules of Origin,Trade Policy,Rules of Origin,TF054105-DONOR FUNDED OPERATION ADMINISTRATION FEE INCOME AND EXPENSE ACCOUNT,Environmental Economics&Policies,Economic Theory&Research
Pattern and process in Amazon tree turnover, 1976-2001
No full textPrevious work has shown that tree turnover, tree biomass and large liana densities have increased in mature tropical forest plots in the late twentieth century. These results point to a concerted shift in forest ecological processes that may already be having significant impacts on terrestrial carbon stocks, fluxes and biodiversity. However, the findings have proved controversial, partly because a rather limited number of permanent plots have been monitored for rather short periods. The aim of this paper is to characterize regional-scale patterns of 'tree turnover' (the rate with which trees die and recruit into a population) by using improved datasets now available for Amazonia that span the past 25 years. Specifically, we assess whether concerted changes in turnover are occurring, and if so whether they are general throughout the Amazon or restricted to one region or environmental zone. In addition, we ask whether they are driven by changes in recruitment, mortality or both. We find that: (i) trees 10 cm or more in diameter recruit and die twice as fast on the richer soils of southern and western Amazonia than on the poorer soils of eastern and central Amazonia; (ii) turnover rates have increased throughout Amazonia over the past two decades; (iii) mortality and recruitment rates have both increased significantly in every region and environmental zone, with the exception of mortality in eastern Amazonia; (iv) recruitment rates have consistently exceeded mortality rates; (v) absolute increases in recruitment and mortality rates are greatest in western Amazonian sites; and (vi) mortality appears to be lagging recruitment at regional scales. These spatial patterns and temporal trends are not caused by obvious artefacts in the data or the analyses. The trends cannot be directly driven by a mortality driver (such as increased drought or fragmentation-related death) because the biomass in these forests has simultaneously increased. Our findings therefore indicate that long-acting and widespread environmental changes are stimulating the growth and productivity of Amazon forests
EO9 (Apaziquone): from the clinic to the laboratory and back again
No full textEO9 (Apaziquone) is a bioreductive drug that has a chequered history. It underwent clinical trial but failed to show activity in phase II clinical trials when administered i.v. Poor drug delivery to tumours caused by a combination of rapid pharmacokinetic elimination and poor penetration through avascular tissue were the major factors responsible for EO9’s poor efficacy. Based upon an understanding of why EO9 failed, a further clinical trial against patients with superficial transitional cell carcinoma
of the bladder was conducted. The rationale for this was that intravesical administration directly into the bladder would circumvent the drug delivery problem, and any drug reaching the blood supply would be rapidly cleared thereby reducing the risk of systemic exposure. EO9 was well tolerated, and clinical activity against marker lesions was recorded in both phase I and II clinical trials. This article charts the pharmacological history of EO9 and discusses the potential implications that ‘the EO9 story’ has for the development of other loco-regional therapies
MICROWAVE SPECTROSCOPY OF BUTAN-2-OL - CONFORMATIONS, COMPLEXES AND CLUSTERS
No full textA. K. King and B. J. Howard Chem. Phys. Lett. 348(343), 2001. A. K. King and B. J. Howard J. Mol. Spectrosc., Submitted for publication. A. K. King and B. J. Howard J. Mol. Spectrosc. 201/1(38), 2001.Author Institution: Physical and Theoretical Chemistry Department, University of OxfordThe first rotationally-resolved spectrum of a van der Waals complex formed between two chiral molecules will be presented. The complex is a hetero-chiral dimer of butan-2-ol and the spectrum was observed by Fourier Transform Microwave Spectroscopy in a supersonic . The results of the ab initio calculations used to identify the dimer will also be presented. The microwave spectrum of a complex formed between a butan-2-ol molecule and an argon atom will also be discussed, including a limited amount of structural . This too will be accompanied by an ab initio study. Finally, mention will be made of the detection of six of the nine possible conformational isomers of the butan-2-ol molecule in expansions of argon and . There are still a large number of unassigned lines in the spectrum of butan-2-ol, some of which must be due to the homo-chiral dimer. Work to assign them is ongoing, any new results will be presented
A Critique on the Book Haqiqat-ol Hadiqat: Selections & Selections & Excerpts of All Chapters of Sanai Ghaznavis Hadiqat-ol Haqiqat
No full text“Haqiqat-ol Hadiqat: Selections & Excerpts of All Chapters of Sanai Ghaznavis Hadiqat-ol Haqiqat” is a book compiled by Homeira Zomorodi, with the aim of providing a selection from “Sanai Ghaznavis Hadiqat-ol Haqiqat” book and related commentary. Was the book successful in achieving its purpose of familiarizing Persian literature readers and students with this significant Persian literary work? In order to evaluate the text accuracy, the author refers to valid sources such as Persian dictionaries, the original text of Sana’i Ghaznavi’s book, old Persian texts sharing common anecdotes with the original text, and commentaries and explications. As a result of such evaluation, few shortcomings have been found, some of which can be cited as various writing, editing, and printing-related flaws in the text, and the citations of verses in many cases are incorrect. In several instances, there are also inaccurate interpretations of verses, incorrect presentation of anecdotes and allusions origins, and flawed translation of cited Arabic phrases. Also, many verses are left unexplained
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