Influence of bottom topography on integral constraints in zonal flows with parameterized potential vorticity fluxes

An integral constraint for eddy fluxes of potential vorticity (PV), corresponding to global momentum conservation, is applied to two-layer zonal quasi-geostrophic channel flow. This constraint must be satisfied for any type of parameterization of eddy PV fluxes. Bottom topography strongly influence the integral constraint compared to a flat bottom channel. An analytical solution for the mean flow solution has been found by using asymptotic expansion in a small parameter which is the ratio of the Rossby radius to the meridional extent of the channel. Applying the integral constraint to this solution, one can find restrictions for eddy PV transfer coefficients which relate the eddy fluxes of PV to the mean flow. These restrictions strongly deviate from restrictions for the channel with flat bottom topography

Health care of children

It is estimated that at the present rate of population growth, at least 21,5 million children under the age of 14 years will require health care by the year 2000. With the available medical manpower, it is not possible to provide the present child population with the uniformly high standard of health care to which they are entitled. It is urged that Paediatric Nurse Associates be trained to assist in this regard. A preliminary report of the training scheme introduced for Paediatric Nurse Associates at the Red Cross War Memorial Children's Hospital is presented for discussion and criticism.S. Afr. Med. J., 48, 1752 (1974)

Health care of children

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Proposed Search For The Detection Of Gravitational Waves From Eccentric Binary Black Holes

Most compact binary systems are expected to circularize before the frequency of emitted gravitational waves (GWs) enters the sensitivity band of the ground based interferometric detectors. However, several mechanisms have been proposed for the formation of binary systems, which retain eccentricity throughout their lifetimes. Since no matched-filtering algorithm has been developed to extract continuous GW signals from compact binaries on orbits with low to moderate values of eccentricity, and available algorithms to detect binaries on quasicircular orbits are suboptimal to recover these events, in this paper we propose a search method for detection of gravitational waves produced from the coalescences of eccentric binary black holes (eBBH). We study the search sensitivity and the false alarm rates on a segment of data from the second joint science run of LIGO and Virgo detectors, and discuss the implications of the eccentric binary search for the advanced GW detectors

On the dual cascade in two-dimensional turbulence

We study the dual cascade scenario for two-dimensional turbulence driven by a spectrally localized forcing applied over a finite wavenumber range [k_\min,k_\max] (with k_\min > 0) such that the respective energy and enstrophy injection rates $\epsilon$ and $\eta$ satisfy k_\min^2\epsilon\le\eta\le k_\max^2\epsilon. The classical Kraichnan--Leith--Batchelor paradigm, based on the simultaneous conservation of energy and enstrophy and the scale-selectivity of the molecular viscosity, requires that the domain be unbounded in both directions. For two-dimensional turbulence either in a doubly periodic domain or in an unbounded channel with a periodic boundary condition in the across-channel direction, a direct enstrophy cascade is not possible. In the usual case where the forcing wavenumber is no greater than the geometric mean of the integral and dissipation wavenumbers, constant spectral slopes must satisfy $\beta>5$ and $\alpha+\beta\ge8$, where $-\alpha$ ($-\beta$) is the asymptotic slope of the range of wavenumbers lower (higher) than the forcing wavenumber. The influence of a large-scale dissipation on the realizability of a dual cascade is analyzed. We discuss the consequences for numerical simulations attempting to mimic the classical unbounded picture in a bounded domain.Comment: 22 pages, to appear in Physica

The ocean's saltiness and its overturning

Here we explore the relationship between the mean salinity urn:x-wiley:grl:media:grl55555:grl55555-math-0001 of the ocean and the strength of its Atlantic and Pacific Meridional Overturning Circulations (AMOC and PMOC). We compare simulations performed with a realistically configured coarse‐grained ocean model, spanning a range of mean salinities. We find that the AMOC strength increases approximately linearly with urn:x-wiley:grl:media:grl55555:grl55555-math-0002. In contrast, the PMOC strength declines approximately linearly with urn:x-wiley:grl:media:grl55555:grl55555-math-0003 until it reaches a small background value similar to the present‐day ocean. Well‐established scaling laws for the overturning circulation explain both of these dependencies on urn:x-wiley:grl:media:grl55555:grl55555-math-0004

Adjustable levels of strong turbulence in a positive/negative ion plasma

Positive/negative ion plasmas, composed of Ba+, SF6−, and residual electrons, were observed to display characteristics of strong turbulence.Experiments on the UCI Q machine linked the presence of negative ions (and the depletion of electrons) with large density fluctuations (δn/n≂1), large‐amplitude, low‐frequency electrostatic noise (f≤20 kHz), and rapid transport of ions across magnetic field lines (D⊥≂104 cm2/sec). Ion velocity distributions were heated parallel to and cooled perpendicular to the confining magnetic field. The partial pressure of gaseous SF6 was shown to serve as a regulator of plasma turbulence. Turbulence levels could be smoothly varied from quiescent states (δn/n≂0.01) to strongly turbulent states (δn/n≂1)

A Cross-Over in the Enstrophy Decay in Two-Dimensional Turbulence in a Finite Box

The numerical simulation of two-dimensional decaying turbulence in a large but finite box presented in this paper uncovered two physically different regimes of enstrophy decay. During the initial stage, the enstrophy, generated by a random Gaussian initial condition, decays as t^{-gamma} with gamma approximately 0.7-0.8. After that, the flow undergoes a transition to a gas or fluid composed of distinct vortices. Simultaneously, the magnitude of the decay exponent crosses over to gamma approximately 0.4. An exact relation for the total number of vortices, N(t), in terms of the mean circulation of an individual vortex is derived. A theory predicting that N(t) is proportional to t^{-xi} and the magnitudes of exponents gamma=2/5 and xi=4/5 is presented and the possibility of an additional very late-time cross-over to gamma=1/3 and xi=2/3 is also discussed.Comment: 11 pages, 7 figure

Understanding the training and education needs of homecare workers supporting people with dementia and cancer: a systematic review of reviews

Many people with dementia, supported by family carers, prefer to live at home and may rely on homecare support services. People with dementia are also often living with multimorbidities, including cancer. The main risk factor for both cancer and dementia is age and the number of people living with dementia and cancer likely to rise. Upskilling the social care workforce to facilitate more complex care is central to national workforce strategies and challenges. Training and education development must also respond to the key requirements of a homecare workforce experiencing financial, recruitment and retention difficulties. This systematic review of reviews provides an overview of dementia and cancer training and education accessible to the homecare workforce. Findings reveal there is a diverse range of training and education available, with mixed evidence of effectiveness. Key barriers and facilitators to effective training and education are identified in order to inform future training, education and learning development for the homecare workforce supporting people with dementia and cancer

Ion acceleration and anomalous transport in the near wake of a plasma limiter

Ion acceleration and anomalous transport were studied experimentally in the near wake region of an electrically floating disk limiter immersed in two different types of collisionless, supersonically flowing, magnetized plasmas: the first initially quiescent, the second initially turbulent. Ion densities and velocity distributions were obtained using a nonperturbing laser induced fluorescence diagnostic. Large-amplitude, low-frequency turbulence was observed at the obstacle edge and in the wake. Rapid ion and electron configuration space transport and ion velocity space transport were observed. Configuration space and velocity space transport were similar for both quiescent and turbulent plasma-obstacle systems, suggesting that plasma-obstacle effects outweigh the effects of initial plasma turbulence levels