2,066 research outputs found
The Former USSR Forest Sector and Capital Constraints
This study presents an analysis of the likely capital constraints that Russia and other republics of the former Soviet Union will face under evolving competitive market conditions. As such it serves as a first step in determining the future of forestry in the former Soviet republics, particularly Russia.
The objectives of the study are to identify likely competitive price responses in the former Soviet Union market for roundwood, the likely impacts of different levels of roundwood exports on international prices and the feedback of international prices may have on the domestic price. The study postulates that, without adequate levels of investments in harvesting and processing capacity, domestic demand -- with below international market prices -- will further erode the existing capital base. As a consequence capital constraints will lead to serious shortages in wood supply in the near future in the absence of capital investment. A more rapid approach to market prices would force serious inflationary pressures on domestic demand.
The results of the study may be used to determine possible policy strategies needed to forestall a decline in output in the forest sector. A collapse of the forest sector will lead to serious wood shortages in meeting the domestic demands of former Soviet republics and may lead to a deterioration in the environment. Lower returns to the sector will limit forest management activities. The forest sector may also miss the opportunity to raise foreign exchange in international markets
Epicyclic frequencies derived from the effective potential: simple and practical formulae
We present and discuss a short and simple derivation of orbital epicyclic
frequencies for circular geodesic orbits in stationary and axially symmetric
spacetimes. Such spacetimes include as special cases analytically known black
hole Kerr and Schwarzschild spacetimes, as well as the analytic Hartle-Thorne
spacetime and all numerically constructed spacetimes relevant for rotating
neutron stars. Our derivation follows directly from energy and angular momentum
conservation and it uses the concept of the effective potential. It has never
been published, except for a few special cases, but it has already become a
part of the common knowledge in the field.Comment: Invited lecture at the conference "From X-ray Binaries to Quasars:
Black Hole Accretion on All Mass Scales", 13-15 July, 2004, Amsterda
Laboratory simulation of cometary x rays using a high-resolution microcalorimeter
X-ray emission following charge exchange has been studied on the University
of California Lawrence Livermore National Laboratory electron beam ion traps
EBIT-I and EBIT-II using a high-resolution microcalorimeter. The measured
spectra include the K-shell emission from hydrogenlike and heliumlike C, N, O,
and Ne needed for simulations of cometary x-ray emission. A comparison of the
spectra produced in the interaction of O8+ with N2 and CH4 is presented that
illustrates the dependence of the observed spectrum on the interaction gas.Comment: 11 pages, 2 figure
Multiplicity distributions inside parton cascades developing in a medium
The explanation of the suppression of high-pT hadron yields at RHIC in terms
of jet-quenching implies that the multiplicity distributions of particles
inside a jet and jet-like particle correlations differ strongly in
nucleus-nucleus collisions at RHIC or at the LHC from those observed at e+e- or
hadron colliders. We present a framework for describing the medium-induced
modification, which has a direct interpretation in terms of a probabilistic
medium-modified parton cascade, and which treats leading and subleading partons
on an equal footing. We show that our approach can account for the strong
suppression of single inclusive hadron spectra measured in Au-Au collisions at
RHIC, and that this implies a characteristic distortion of the single inclusive
distribution of soft partons inside the jet. We determine, as a function of the
jet energy, to what extent the soft fragments within a jet can be measured
above some momentum cut.Comment: 5 pages, 4 eps-figures; talk given at Hot Quarks 2006, Villasimius
(Sardinia, Italy), May 15-20, 200
Examining national and district-level trends in neonatal health in Peru through an equity lens:A success story driven by political will and societal advocacy
Abstract Background Peru has impressively reduced its neonatal mortality rate (NMR). We aimed, for the period 2000–2013, to: (a) describe national and district NMR variations over time; (b) assess NMR trends by wealth quintile and place of residence; (c) describe evolution of mortality causes; (d) assess completeness of registered mortality; (e) assess coverage and equity of NMR-related interventions; and (f) explore underlying driving factors. Methods We compared national NMR time trends from different sources. To describe NMR trends by wealth quintiles, place of residence and districts, we pooled data on births and deaths by calendar year for neonates born to women interviewed in multiple surveys. We disaggregated coverage of NMR-related interventions by wealth quintiles and place of residence. To identify success factors, we ran regression analyses and combined desk reviews with qualitative interviews and group discussions. Results NMR fell by 51 % from 2000 to 2013, second only to Brazil in Latin America. Reduction was higher in rural and poorest segments (52 and 58 %). District NMR change varied by source. Regarding cause-specific NMRs, prematurity decreased from 7.0 to 3.2 per 1,000 live births, intra-partum related events from 2.9 to 1.2, congenital abnormalities from 2.4 to 1.8, sepsis from 1.9 to 0.8, pneumonia from 0.9 to 0.4, and other conditions from 1.2 to 0.7. Under-registration of neonatal deaths decreased recently, more in districts with higher development index and lower rural population. Coverage of family planning, antenatal care and skilled birth attendance increased more in rural areas and in the poorest quintile. Regressions did not show consistent associations between mortality and predictors. During the study period social determinants improved substantially, and dramatic out-of-health-sector and health-sector changes occurred. Rural areas and the poorest quintile experienced greater NMR reduction. This progress was driven, within a context of economic growth and poverty reduction, by a combination of strong societal advocacy and political will, which translated into pro-poor implementation of evidence-based interventions with a rights-based approach. Conclusions Although progress in Peru for reducing NMR has been remarkable, future challenges include closing remaining gaps for urban and rural populations and improving newborn health with qualified staff and intermediate- and intensive-level health facilities
Stability of trapped Bose-Einstein condensates
In three-dimensional trapped Bose-Einstein condensate (BEC), described by the
time-dependent Gross-Pitaevskii-Ginzburg equation, we study the effect of
initial conditions on stability using a Gaussian variational approach and exact
numerical simulations. We also discuss the validity of the criterion for
stability suggested by Vakhitov and Kolokolov. The maximum initial chirp
(initial focusing defocusing of cloud) that can lead a stable condensate to
collapse even before the number of atoms reaches its critical limit is obtained
for several specific cases. When we consider two- and three-body nonlinear
terms, with negative cubic and positive quintic terms, we have the conditions
for the existence of two phases in the condensate. In this case, the magnitude
of the oscillations between the two phases are studied considering sufficient
large initial chirps. The occurrence of collapse in a BEC with repulsive
two-body interaction is also shown to be possible.Comment: 15 pages, 11 figure
Herd-level risk factors of bovine tuberculosis in England and Wales after the 2001 foot-and-mouth disease epidemic
We present the results of a 2005 case–control study of bovine tuberculosis (bTB) breakdowns in English and Welsh herds. The herd management, farming practices, and environmental factors of 401matched pairs of case and control herds were investigated to provide a picture of herd-level risk factors in areas of varying bTB incidence. A global conditional logistic regression model, with region-specific variants, was used to compare case herds that had experienced a confirmed bTB breakdown to contemporaneous control herds matched on region, herd type, herd size, and parish testing interval. Contacts with cattle from contiguous herds and sourcing cattle from herds with a recent history of bTB were associated with an increased risk in both the global and regional analyses. Operating a farm over several premises, providing cattle feed inside the housing, and the presence of badgers were also identified as significantly associated with an increased bTB risk. Steps taken to minimize cattle contacts with neighboring herds and altering trading practices could have the potential to reduce the size of the bTB epidemic. In principle, limiting the interactions between cattle and wildlife may also be useful; however this study did not highlight any specific measures to implement
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