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Atmospheric effects of the emerging mainland Chinese transportation system at and beyond the regional scale
Local surface travel needs in the People's Republic of China (mainland China) have traditionally been met largely by nonpolluting bicycles. A major automobile manufacturing/importing effort has begun in the country over the last decade, and planning documents indicate that the Chinese may strive to acquire more than 100 million vehicles early in the next century. By analogy with large automotive fleets already existing in the western world, both regional and global scale pollution effects are to be expected from the increase. The present work adopts the latest projections of Chinese automobile manufacture and performs some quantitative assessments of the extent of pollution generation. Focus for the investigation is placed upon the oxidant ozone. Emissions of the precursor species nitrogen oxides and volatile organics are constructed based on data for the current automotive sector in the eastern portion of the United States. Ozone production is first estimated from measured values for continental/oceanic scale yields relative to precursor oxidation. The estimates are then corroborated through idealized two dimensional modeling of the photochemistry taking place in springtime air flow off the Asian land mass and toward the Pacific Ocean. The projected fleet sizes could increase coastal and remote oceanic ozone concentrations by tens of parts per billion (ppb) in the lower troposphere. Influences on the tropospheric aerosol system and on the major greenhouse gas carbon dioxide are treated peripherally. Nitrogen oxides created during the vehicular internal combustion process will contribute to nitrate pollution levels measured in the open Pacific. The potential for soot and fugitive dust increases should be considered as the automotive infrastructure develops. Since the emerging Chinese automotive transportation system will represent a substantial addition to the global fleet and all the carbon in gasoline is eventually oxidized completely, a significant rise in global carbon dioxide inputs will ensue as well. Some policy issues are treated preliminary. The assumption is made that alterations to regional oxidant/aerosol systems and to terrestrial climate are conceivable. The likelihood that the Chinese can achieve the latest vehicle fleet goals is discussed, from the points of view of new production, positive pollution feedbacks from a growing automobile industry, and known petroleum reserves. Vehicular fuel and maintenance options lying before the Chinese are outlines and compared. To provide some perspective on the magnitude of the environmental changes associated with an Asian automotive buildup, recent estimates of the effects of future air traffic over the Pacific Rim are described
A mixed-mode shell-model theory for nuclear structure studies
We introduce a shell-model theory that combines traditional spherical states,
which yield a diagonal representation of the usual single-particle interaction,
with collective configurations that track deformations, and test the validity
of this mixed-mode, oblique basis shell-model scheme on Mg. The correct
binding energy (within 2% of the full-space result) as well as low-energy
configurations that have greater than 90% overlap with full-space results are
obtained in a space that spans less than 10% of the full space. The results
suggest that a mixed-mode shell-model theory may be useful in situations where
competing degrees of freedom dominate the dynamics and full-space calculations
are not feasible.Comment: 20 pages, 8 figures, revtex 12p
A review of phosphorus homeostasis and the impact of different types and amounts of dietary phosphate on metabolism and renal health in cats
Elevated concentrations of serum phosphate are linked with progression and increased case fatality rate in animals and humans with chronic kidney disease. Elevated concentrations of serum phosphate can be a risk factor for development of renal and cardiovascular diseases or osteoporosis in previously healthy people. In rodents, an excess intake of dietary phosphorus combined with an inverse dietary calcium : phosphorus ratio (<1 : 1) contributes to renal calcification. Renal injury also has occured in cats fed experimental diets supplemented with highly soluble phosphate salts, especially in diets with inverse calcium : phosphorus ratios. However, not all phosphorus sources contribute similarly to this effect. This review, which focuses on cats, summarizes the published evidence regarding phosphorus metabolism and homeostasis, including the relative impact of different dietary phosphorus sources, and their impact on the kidneys. No data currently shows that commercial cat foods induce renal injury. However, some diets contain high amounts of phosphorus relative to recommendations and some have inverse Ca : P ratios and so could increase the risk for development of kidney disease. While limiting the use of highly soluble phosphates appears to be important, there are insufficient data to support a specific upper limit for phosphate intake. This review also proposes areas where additional research is needed in order to strengthen conclusions and recommendations regarding dietary phosphorus for cats
Hypervelocity Stars: Predicting the Spectrum of Ejection Velocities
The disruption of binary stars by the tidal field of the black hole in the
Galactic Center can produce the hypervelocity stars observed in the halo. We
use numerical models to simulate the full spectrum of observable velocities of
stars ejected into the halo by this binary disruption process. Our model
includes a range of parameters for binaries with 3-4 M_Solar primaries,
consideration of radial orbits of the ejected stars through an approximate mass
distribution for the Galaxy, and the impact of stellar lifetimes. We calculate
the spectrum of ejection velocities and reproduce previous results for the mean
ejection velocity at the Galactic center. The model predicts that the full
population of ejected stars includes both the hypervelocity stars with
velocities large enough to escape from the Galaxy and a comparable number of
ejected, but bound, stars of the same stellar type. The predicted median speeds
of the population of ejected stars as a function of distance in the halo are
consistent with current observations. Combining the model with the data also
shows that interesting constraints on the properties of binaries in the
Galactic Center and on the mass distribution in the Galaxy can be obtained even
with modest samples of ejected stars.Comment: 26 pages, including 6 figures, accepted for publication in the
Astrophysical Journa
SU(3) symmetry breaking in lower fp-shell nuclei
Results of shell-model calculations for lower fp-shell nuclei show that SU(3)
symmetry breaking in this region is driven by the single-particle spin-orbit
splitting. However, even though states of the yrast band exhibit SU(3) symmetry
breaking, the results also show that the yrast band B(E2) values are
insensitive to this fragmentation of the SU(3) symmetry; specifically, the
quadrupole collectivity as measured by B(E2) transition strengths between low
lying members of the yrast band remain high even though SU(3) appears to be
broken. Results for and using the Kuo-Brown-3
two-body interaction are given to illustrate these observations.Comment: Updated to the published versio
Furanylfentanyl. ANNEX 1. Technical report on N-phenyl-N- [1-(2-phenylethyl)piperidin-4-yl]furan- 2-carboxamide (furanylfentanyl).
This publication presents the data and findings of the risk assessment on furanylfentanyl (N-phenyl-N-[1-(2-phenylethyl)piperidin-4-yl]furan-2-carboxamide), carried out by the extended Scientific Committee of the EMCDDA on 23 May 2017. The Risk Assessment Report, which was submitted to the European Commission and the Council of the European Union on 23 May 2017, examines the health and social risks of the drug, information on international trafficking and the involvement of organised crime, as well as a consideration of the potential implications of subjecting the drug to control measures. Furanylfentanyl is the fourteenth new psychoactive substance to be risk assessed under the terms of Council Decision 2005/387/JHA. On the basis of the Risk Assessment Report - and on the initiative of the European Commission - on 15 November 2017, the Council decided that furanylfentanyl should be subject to control measures across the Member States. This decision was adopted in the final stage of the three-step process - early warning, risk assessment and control of new psychoactive substances - established by the Council Decision 2005/387/JHA. This legal framework allows the EU institutions and Member States to act on all new and potentially threatening narcotic and psychotropic drugs which appear on the European drug scene, with the EMCDDA and Europol, in collaboration with their respective networks playing a central role in the early detection of such substances as well as the harms caused by their use - information that underpins risk assessment, and, ultimately, decision-making
Technical report on N-(4-fluorophenyl)-N-(1-phenethylpiperidin-4-yl)isobutyramide (4-fluoroisobutyrylfentanyl; 4F-iBF). Annex 1 to the Risk Assessment Report on N-(4-fluorophenyl)-N-(1-phenethylpiperidin-4-yl)isobutyramide (4-fluoroisobutyrylfentanyl; 4F-iBF)
In accordance with Article 6 of Council Decision 2005/387/JHA on the information exchange, risk
assessment and control of new psychoactive substances
Technical report on N-phenyl-N-[1-(2-phenylethyl)piperidin-4-yl]oxolane-2-carboxamide (tetrahydrofuranylfentanyl; THF-F). Annex 1 to the Risk Assessment Report on N-phenyl-N-[1-(2-phenylethyl)piperidin-4-yl]oxolane-2- carboxamide (tetrahydrofuranylfentanyl).
In accordance with Article 6 of Council Decision 2005/387/JHA on the information exchange,
risk assessment and control of new psychoactive substances
Sensitivity and noise in THz electro-optic upconversion radiometers
This paper presents a study of noise in room-temperature THz radiometers that use THz-to-optical upconversion followed by optical detection of thermal radiation. Despite some undesired upconverted thermal noise, no noise is intrinsically introduced by efcient electro-optic modulation via a sumfrequency-generation process in high quality factor (Q) whispering-gallery mode (WGM) resonators. However, coherent and incoherent optical detection results in fundamentally diferent noise characteristics. The analysis shows that the upconversion receiver is quantum limited like conventional amplifers and mixers, only when optical homodyne or heterodyne detection is performed. However, this type of receiver shows advantages as a THz photon counter, where counting is in the optical domain. Theoretical predictions show that upconversion-based room-temperature receivers can outperform state-of-the-art cooled and room-temperature THz receivers based on low-noise amplifers and mixers, provided that a photon conversion efciency greater than 1% is realized. Although the detection bandwidth is naturally narrow due to the highly resonant electro-optic modulator, it is not fundamentally limited and can be broadened by engineering selective optical coupling mechanisms to the resonator.Ministerio de EconomĂa y Competitividad (MINECO) (TEC2013-47753-C3); Comunidad de Madrid MARTINLARA Project (ref. P2018/NMT-4333); FUNDACION SENER; Banco Santander (TEC2016-76997- C3-2-R); 2017 UC3M-Santander Chair of Excellence
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