Sowing in the autumn season : exploring benefits of green care farms for dementia patients

In the Netherlands an increasing number of farms combine agricultural production with care services for people with care needs. It is generally believed that these green care farms (GCFs) have beneficial effects on the health status of a diversity of target groups. At present, empirical studies testing this hypothesis are scarce. The main objective of the studies described in this thesis was to gain insight into the potential benefits of day care at GCFs for community‐dwelling older dementia patients. Day care at GCFs was therefore compared with day care at regular day care facilities (RDCFs). In view of the differences between both day care types regarding the day care setting and day care program it was hypothesized that they would differ in their effects on the health status of dementia patients. In two cross‐sectional studies it was tested to what extent the day program of dementia patients at GCFs differed from those at RDCFs. It appeared that at GCFs, dementia patients were (physically) more active, participated in more diverse activities, were more outdoors, and had more opportunities to perform activities in smaller groups than those at RDCFs. It was tested whether these differences resulted into different effects for five domains of health: dietary intake, cognition, emotional well‐being, behaviour, and functional performance. In a comparative cross‐sectional study dietary intake of dementia patients attending day care at GCFs or RDCFs was recorded both at home and during their time at the day care facility. The study showed that dementia patients attending day care at GCFs had significantly higher intakes of energy, carbohydrate, and fluid than their counterparts attending day care at RDCFs. In a cohort study, rates of change during 1 year in cognitive functioning, emotional well‐being, behavioural symptoms, and functional performance were compared between dementia patients attending day care at GCFs and RDCFs. Functioning in these domains remained rather stable and no differences were observed between subjects from GCFs and RDCFs. In the cohort study, also caregiver burden of family caregivers of these dementia patients was assessed. Caregivers’ quality of life, emotional distress, and feelings of competence remained rather stable in family caregivers of dementia patients from both day care settings. In conclusion, the present work has shown that GCFs exceeded RDCFs in offering older dementia patients a diverse day program and in stimulating their dietary intake. The latter may result into a better preserved nutritional status in dementia patients attending day care at GCFs than in those attending day care at RDCFs. GCFs and RDCFs were equally effective in preventing significant decrease of cognitive functioning, emotional well‐being, and functional performance and in preventing significant increase of the number of behavioural symptoms. Both day care types further prevented significant increase of caregiver burden. Day care at GCFs is a new and valuable addition to the present care modalities for community‐dwelling older dementia patients and their caregiver

Unphysical Operators in Partially Quenched QCD

We point out that the chiral Lagrangian describing pseudo-Goldstone bosons in partially quenched QCD has one more four-derivative operator than that for unquenched QCD with three flavors. The new operator can be chosen to vanish in the unquenched sector of the partially quenched theory. Its contributions begin at next-to-leading order in the chiral expansion. At this order it contributes only to unphysical scattering processes, and we work out some examples. Its contributions to pseudo-Goldstone properties begin at next-to-next-to-leading order, and we determine their form. We also determine all the zero and two derivative operators in the $O(p^6)$ partially quenched chiral Lagrangian, finding three more than in unquenched QCD, and use these to give the general form of the analytic next-to-next-to-leading order contributions to the pseudo-Goldstone mass and decay constant. We discuss the general implications of such additional operators for the utility of partially quenched simulationsComment: 13 pages, 11 figures Version 2: Additional footnote and parenthesis in section

Transmission of force through particulate systems with restricted geometry

Particle systems may be characterised by a knowledge of the dimensions of the individual particles. By using the Feret's diameter distribution and the random filament distribution of an iron powder the characterisation of a system of the powder particles, constrained in a cylindrical die, has been achieved. The Monte Carlo method has been used to simulate the transmission of force through the model created by this characterisation. The results of 500 Monte Carlo simulations have been used to produce a description of the force due to one surface particle at various points in the system. Using this diagram together with a knowledge of the spatial distribution of the surface particles and the dimensions of the die it was possible to produce: (1) curves of side wall pressure vs. depth in the die for various loads; (2) curves of applied to transmitted pressure for various height:diameter ratios; (3) curves of friction loss at the walls vs. depth for different height:diameter ratios. The differences between the experimentally determined values and the values predicted on the basis of the model have been explained in terms of the assumptions made, and suggestions made as to how these may be eliminated

On the theory of beta-radioactivity IV : The polarization of beta-rays emitted by aligned nuclei in allowed transitions

The consequences of alignment of nuclei, which show allowed ß-transitions, are investigated. A general formula is derived for the transition probability of an allowed β-transition, in which the direction of emission of electron and neutrino, the polarization of the electron and the orientation of the nuclear spin are taken into account. The calculations have been made for a Hamiltonian for the β-interaction, which is an arbitrary "mixture" of the five invariants of the Dirac theory. The influence of the nuclear charge has, however, been neglected. From this formula the following results are immediately obtained: The angular distribution of the β-radiation remains spherically symmetric if the nuclei are aligned, so that the alignment cannot be detected in this way. The emitted β-radiation is polarized and the degree of polarization follows from the general formula. If we take the special case that the interaction Hamiltonian is of the tensor or the axial vector type and if the β-rays are emitted perpendicular to the direction of the nuclear spin of completely aligned nuclei with nuclear spin ji, the degree of polarization is given by: a) 1/Eif ji = jf + 1, b) 1/E(ji + 1), if ji = jf,c)ji/E(ji + 1), if ji = ji - 1. (E is the relativistic energy of the electrons, E ≈ 1 for small kinetic energies; jf gives the spin of the final nucleus)

Observed Lagrangian Transition of Stratocumulus into Cumulus during ASTEX: Mean State and Turbulence Structure

Aircraft measurements made during the "First Lagrangian" of the Atlantic Stratocumulus Transition Experiment (ASTEX) between 12 and 14 June 1992 are presented. During this Lagrangian experiment an air mass was followed that was advected southward by the mean wind. Five aircraft flights were undertaken to observe the transition of a stratocumulus cloud deck to thin and broken stratocumulus clouds penetrated by cumulus from below. From the horizontal aircraft legs the boundary layer mean structure, microphysics, turbulence structure, and entrainment were analyzed. The vertical profiles of the vertical velocity skewness are shown to illustrate the transition of a cloudy boundary layer predominantly driven by longwave radiative cooling at the cloud top to one driven mainly by convection due to an unstable surface stratification and cumulus clouds. During the last flight before the stratocumulus deck was observed to be broken and replaced by cumuli, the total water flux, the virtual potential temperature flux, and the vertical velocity variance in the stratocumulus cloud layer were found significantly larger compared with the previous flights. To analyze the cloud-top stability the mean jumps of conserved variables across the inversion were determined from porpoising runs through the cloud top. These jumps were compared with cloud-top entrainment instability criteria discussed in the literature. It is suggested that enhanced entrainment of dry air is a key mechanism in the stratocumulus-cumulus transition

On the theory of beta-radioactivity III : The influence of electric and magnetic fields on polarized electron beams

The influence of electric and magnetic fields on the spin orientation (polarization) of electrons in a beam is calculated according to the Pauli spin theory and the Dirac theory. For the cases, where the field is perpendicular or parallel to a polarized electron beam, the following results are found. Transverse electric field. In the non-relativistic approximation the spin orientation remains constant in space, even if the beam is deflected; the relativistic formula gives for the ratio of the rotation of the spin orientation and the angle of deflection of the beam: Ekin/E (ratio of kinetic energy and total energy, i.e., including the rest mass). Transverse magnetic field. The spin orientation does not change in relation to the direction of propagation. Longitudinal electric field. Though the beam is accelerated (or retarded) the spin orientation remains constant in space. Longitudinal magnetic field. The spin orientation rotates about the direction of propagation. It is shown that longitudinal polarization of electron beams (spins parallel or antiparallel to the direction of propagation) can be observed by means of an electric deflection of the beam and a scattering experiment in succession

Gastromermis massei n. sp. (Nematoda : Mermithidae) : a parasite of blackflies Simulium wolffhuengeli Enderlein (Simuliidae : Diptera) in Argentina

#Gastromermis massei n. sp. (#Nematoda : #Mermithidae) est décrit et illustré. Cette espèce, parasite de #Simulium wolffhuengeli Enderlein (#Simuliidae : #Diptera), a été trouvée dans la rivière Cosquin, à Cordoba, Argentine. Elle peut être séparée des autres espèces du genre par la combinaison des caractères suivants : présence de six cordes hypodermiques, position de l'orifice buccal, forme du pore amphidial, absence de volets vulvaires, longueur et forme des extrêmités proximale et distale des spicules, nombre de papilles génitales et longueur de l'appendice caudal chez les individus postparasitaires. #G. massei n. sp. est la sizième espèce du genre décrite en Argentine, genre le mieux représenté chez les #Mermithidae de ce pays. Une clef d'identification des espèces du genre à six cordes hypodermiques est proposé. (Résumé d'auteur

Analogies between Mass-Flux and Reynolds-Averaged Equations

In many large-scale models mass-flux parameterizations are applied to prognose the effect of cumulus cloud convection on the large-scale environment. Key parameters in the mass-flux equations are the lateral entrainment and detrainment rates. The physical meaning of these parameters is that they quantify the mixing rate of mass across the thermal boundaries between the cloud and its environment. The prognostic equations for the updraft and downdraft value of a conserved variable are used to derive a prognostic variance equation in the mass-flux approach. The analogy between this equation and the Reynolds-averaged variance equation is discussed. It is demonstrated that the prognostic variance equation formulated in mass-flux variables contains a gradient-production, transport, and dissipative term. In the latter term, the sum of the lateral entrainment and detrainment rates represents an inverse timescale of the dissipation. Steady-state solutions of the variance equations are discussed. Expressions for the fractional entrainment and detrainment coefficients are derived. Also, solutions for the vertical flux of an arbitrary conserved variable are presented. For convection in which the updraft fraction equals the downdraft fraction, the vertical flux of the scalar flows down the local mean gradient. The turbulent mixing coefficient is given by the ratio of the vertical mass flux and the sum of the fractional entrainment and detrainment coefficients. For an arbitrary updraft fraction, however, flux correction terms are part of the solution. It is shown that for a convective boundary layer these correction terms can account for countergradient transport, which is illustrated from large eddy simulation results. In the cumulus convection limit the vertical flux flows down the cloud gradient. It is concluded that in the mass-flux approach the turbulent mixing coefficients, and the correction terms that arise from the transport term, are very similar to closures applied to the Reynolds-averaged equations