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A review of the Yorkshire and Humber regional waste strategy
Managing waste has become a primary issue for regional planners. This article reports on the institutional process underpinning the region’s strategy and the stages in its production. It emphasises that there has been a watering down of the target for household waste production without appropriate explanation
Competition between charge and spin order in the extended Hubbard model on the triangular lattice
Several new classes of compounds can be modeled in first approximation by
electrons on the triangular lattice that interact through on-site repulsion
as well as nearest-neighbor repulsion . This extended Hubbard model on a
triangular lattice has been studied mostly in the strong coupling limit for
only a few types of instabilities. Using the extended two-particle self
consistent approach (ETPSC), that is valid at weak to intermediate coupling, we
present an unbiased study of the density and interaction dependent crossover
diagram for spin and charge density wave instabilities of the normal state at
arbitrary wave vector. When dominates over and electron filling is
large, instabilities are chiefly in the spin sector and are controlled mostly
by Fermi surface properties. Increasing eventually leads to charge
instabilities. In the latter case, it is mostly the wave vector dependence of
the vertex that determines the wave vector of the instability rather than Fermi
surface properties. At small filling, non-trivial instabilities appear only
beyond the weak coupling limit. There again, charge density wave instabilities
are favored over a wide range of dopings by large at wave vectors
corresponding to superlattice in real space.
Commensurate fillings do not play a special role for this instability.
Increasing leads to competition with ferromagnetism. At negative values of
or , neglecting superconducting fluctuations, one finds that charge
instabilities are favored. In general, the crossover diagram presents a rich
variety of instabilities. We also show that thermal charge-density wave
fluctuations in the renormalized classical regime can open a pseudogap in the
single-particle spectral weight, just as spin or superconducting fluctuations
The effect of sertraline and 8-OH-DPAT on the PTZinduced seizure threshold: Role of the nitrergic system
Purpose Serotonin is a key regulatory neurotransmitter in the CNS which plays an important role in seizure through different receptors, especially the 5HT1A subtype. The role of sertraline through the 5HT1A receptor and nitric oxide interaction on the PTZ-induced seizure threshold was investigated in this study. Method In this study, 70 white male mice were randomly divided into 10 groups including intact control, sham-control and eight experimental groups which received sertraline, 8-OH-DPAT, WAY100635, WAY100635 + sertraline, WAY100635 + 8-OH-DPAT, L-NAME, L-NAME + sertraline and L-NAME + 8-OH-DPAT. After 14 days of treatment in different groups, the PTZ-induced seizure threshold was assessed and the measurement of nitric oxide metabolites in the brain tissue was done with the Greiss method. Results The seizure threshold was significantly increased in the sertraline and 8OH-DPAT receiving groups compared to the sham group (P < 0.001). In the presence of WAY100635, the effect of both sertraline and 8-OH-DPAT in raising the seizure threshold was more prominent (P < 0.001) but on the other hand, in the presence of L-NAME, an increase in the anticonvulsant effect of 8-OH-DPAT was observed, while L-NAME alone had no effect on the seizure threshold (P < 0.001). The NOX concentration was significantly decreased in the 8-OH-DPATtreated group (P < 0.01), while the WAY100657 reversed it and the combination of 8-OH-DPAT with L-NAME reduced the NOX levels (P < 0.001). Conclusions These findings support the anticonvulsant effect of SSRIs and selective 5HT1A receptors, although serotonin receptors other than 5HT1A subtype may be involved and also it is probable that some anticonvulsant effects of the sertraline and 8-OH-DPAT are through the modulation of nitrergic system. © 2016 British Epilepsy Associatio
Lagrangian tracers on a surface flow: the role of time correlations
Finite time correlations of the velocity in a surface flow are found to be
important for the formation of clusters of Lagrangian tracers. The degree of
clustering characterized by the Lyapunov spectrum of the flow is numerically
shown to be in qualitative agreement with the predictions for the white-in-time
compressible Kraichnan flow, but to deviate quantitatively. For intermediate
values of compressibility the clustering is surprisingly weakened by time
correlations.Comment: 4 pages, 5 figures, to be published in PR
Single-particle and collective excitations in a charged Bose gas at finite temperature
The main focus of this work is on the predictions made by the dielectric
formalism in regard to the relationship between single-particle and collective
excitation spectra in a gas of point-like charged bosons at finite temperature
below the critical region of Bose-Einstein condensation. Illustrative
numerical results at weak coupling () are presented within the Random
Phase Approximation. We show that within this approach the single-particle
spectrum forms a continuum extending from the transverse to the longitudinal
plasma mode frequency and leading to a double-peak structure as increases,
whereas the density fluctuation spectrum consists of a single broadening peak.
We also discuss the momentum distribution and the superfluidity of the gas.Comment: 15 pages, 5 figure
Conditions for magnetically induced singlet d-wave superconductivity on the square lattice
It is expected that at weak to intermediate coupling, d-wave
superconductivity can be induced by antiferromagnetic fluctuations. However,
one needs to clarify the role of Fermi surface topology, density of states,
pseudogap, and wave vector of the magnetic fluctuations on the nature and
strength of the induced d-wave state. To this end, we study the generalized
phase diagram of the two-dimensional half-filled Hubbard model as a function of
interaction strength , frustration induced by second-order hopping
, and temperature . In experiment, and
can be controlled by pressure. We use the two-particle self-consistent approach
(TPSC), valid from weak to intermediate coupling. We first calculate as a
function of and the temperature and wave vector at which
the spin response function begins to grow exponentially.D-wave
superconductivity in a half-filled band can be induced by such magnetic
fluctuations at weak to intermediate coupling, but only if they are near
commensurate wave vectors and not too close to perfect nesting conditions where
the pseudogap becomes detrimental to superconductivity. For given there
is thus an optimal value of frustration where the
superconducting is maximum. The non-interacting density of states plays
little role. The symmetry d vs d of the superconducting
order parameter depends on the wave vector of the underlying magnetic
fluctuations in a way that can be understood qualitatively from simple
arguments
Prevention of Drowning by Community-Based Intervention: Implications for Low- and Middle- Income Countries
Background: Drowning is a serious but neglected health problem in low-and middle-income countries.
Objectives: To describe the effectiveness of drowning prevention program on the reduction of drowning mortality rates in rural settings at the north of Iran, and guide its replication elsewhere.
Patients and Methods: This interventional design included pre- and post-intervention observations in the rural area of the Caspian Sea coastline without a comparison community. Cross-sectional data were collected at pre- and post-intervention phases. Outcome evaluation was based on a four-year period (March 2005-March 2009) utilizing drowning registry data for the north of Iran.
Results: The implementation program increased the rate of membership in an organization responsible for promoting safety in high risk areas near the Caspian Sea. Compared to a WHO standardized population, drowning incidence in rural areas of the study demonstrated a continuous decrease in age-specific drowning rate among the oldest victims with a gradual decline during the implementation. In the study area, the epidemiological aspects of the study population were exposed and contributing factors were highlighted.
Conclusions: This study showed that the promotion of passive interventions had a greater effect on drowning rate than that of active interventions
Application Procedures and Practices Futures Human Resource Planning
The most effective element of human resource development and organization of their most valuable asset is of very high importance of the human resource planning and extension and improvement of the level of complexity on the other hand, the progress, the amazing growth of technology, communications, and changes in the period and the emergence of new current problems in the International community, planning methods based on predictions somewhat dumb enough to not seem unreasonable and meet the real needs of the micro and macro levels is not.The inability to accurately predict the future and the growing complexity of the changes made The researchers took advantage of the capabilities and benefits of futures and fixed as it is necessary for planning and forecasting of scientific developments and the political, military, technology, consider.Future research into the human ability to imagine a future issue are considered and makes progress.Future studies, systematic process to identify opportunities and future needs, and to assist major organizations in making decisions, so future studies approach quickly spread among the communities and organizations and special place different areas of science, so in this article has been tried and tested techniques and methods of futures research and application of each of these methods in the field of human resource planning, which can be crucial in the development and promotion organization is explained and described
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