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Velocity-changing collisional effects in nonlinear atomic spectroscopy and photon echo decay in gases
A general theory of atomic dipole coherence under the influence of collisional phase changes, inelastic effects and optically active atom velocity changes, including those due to anisotropic interactions is presented. Velocity change effects are obtained in closed form. Line shapes appear as convolutions of standard pressure broadening contours with velocity-change contours. Width and shift parameters for the He-broadened Na D lines at 2 m bar pressure, 380 K are calculated, as are He-induced photon echo decay rates for these lines. Overall agreement with xperiment is reasonably good
Farrowing accommodation for organic pigs
Newborn piglets in organic farrowing pens have a lower survival rate than in conventional farrowing pens. This difference is mainly caused by housing the sow loose compared to crated and by climatic effects of the outdoor temperature. Organic lactating sows should have at least 7.5 m² indoor area with straw and a 2.5 m² outdoor run.
The aim of the project was to increase piglet survival in order to improve animal welfare as well as the profitability of organic farms.
In the experiment we compared survival and behaviour in 3 pen types: type 1 with outdoor run, type 2 with an indoor run and a higher proportion of solid floor and type 3 without run. Data was analysed with Analysis of Variance using parity and liveborn piglets as covariables. Results of 131 litters in total showed 9.6a, 10.8b and 9.4a (p=0.05) weaned piglets per litter for pen type 1, 2 and 3. Fouling scores indicating dunging behaviour in the indoor lying area showed 13a, 21b and 19b (p=0.04) for pen types 1, 2 and 3. We found a tendency that litters with high survival rates used the separate piglet nest sooner for lying than the litters with low survival rates. Climatic conditions seemed to be crucial for the vitality and survival of the newborn piglets.
The better climatic conditions combined with the higher proportion of solid floor resulted in a higher survival rate of the piglets. These results are currently used in a second experiment focussing on extra heating around farrowing and solid floor proportion in a new farrowing accommodation
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The research crisis in American institutions of complementary and integrative health: one proposed solution for chiropractic profession.
A crisis confronts the Complementary and Integrative Health (CIH) teaching institutions in the US. Research infrastructure is needed to build and sustain productive research programs and retain their own research faculty. In most health professions, this infrastructure is largely built through research grants. In CIH, most educational institutions are funded through student tuition, which has historically also had to be the source for building their research programs. Only a limited number of these institutions have emerged as National Institute of Health (NIH) grant-funded programs. As a result, the American chiropractic institutions have seen a retrenchment in the number of active research programs. In addition, although research training programs e.g., NIH's K awards are available for CIH researchers, these programs generally result in these researchers leaving their institutions and depriving future CIH practitioners of the benefit of being trained in a culture of research. One proposed solution is to leverage the substantial research infrastructure and long history of collaboration available at the RAND Corporation (https://www.rand.org) This article presents the proposed five components of the RAND Center for Collaborative CIH Research and the steps required to bring it to being: 1) the CIH Research Network - an online resource and collaborative site for CIH researchers; 2) the CIH Research Advisory Board - the governing body for the Center selected by its members; 3) the RAND CIH Interest Group - a group of RAND researchers with an interest in and who could provide support to CIH research; 4) CIH Researcher Training - access to existing RAND research training as well as the potential for the Center to provide a research training home for those with training grants; and 5) CIH RAND Partnership for Research - a mentorship program to support successful CIH research. By necessity the first step in the Center's creation would be a meeting between the heads of interested CIH institutions to work out the details and to obtain buy-in. The future success of CIH-directed research on CIH will require a pooling of talent and resources across institutions; something that the American chiropractic institutions have not yet been able to achieve. This article discusses one possible solution
Total destruction of invariant tori for the generalized Frenkel-Kontorova model
We consider generalized Frenkel-Kontorova models on higher dimensional
lattices. We show that the invariant tori which are parameterized by continuous
hull functions can be destroyed by small perturbations in the topology
with
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