209 research outputs found
Effect of protein deficiency on absorption, transport and distribution of α-tocopherol in the rat
The absorption, transport and distribution of α-[3H]tocopherol were greatly decreased in protein deficiency. This was reflected in the subcellular distribution of α-[3H]tocopherol in livers of protein-deficient rats. The ratio, bound: free for α-[3H]tocopherol, also decreased in both serum and liver cytosol. After protein refeeding, absorption, transport and distribution patterns of α-[3H]tocopherol for the protein-deficient rats were restored to patterns similar to those of control animals
Involvement of binding lipoproteins in the absorption and transport of α-tocopherol in the rat
1. Specific lipoproteins binding α-tocopherol but not its known metabolites have been isolated and identified from cytosol of rat intestinal mucosa and from serum. 2. A timestudy of the appearance of the orally administered α-[3H]tocopherol with these lipoproteins indicates that very-low-density lipoprotein of serum acts as a carrier of the vitamin. 3. The involvement of the mucosal lipoprotein in the absorption of the vitamin from the intestine has been inferred from observations on the amounts of α-tocopherol in serum of orotic acid-fed rats where release of lipoproteins from the liver to serum is completely inhibited. A considerable decrease in the association of α-tocopherol with serum very-low-density lipoprotein under this condition is interpreted to mean that serum lipoproteins are limiting factors for the transport of the vitamin across the intestine and that this is possibly effected by exchange of α-tocopherol between serum very-low-density lipoprotein and mucosal lipoprotein
Involvement of binding lipoproteins in the absorption and transport of α-tocopherol in the rat
Photoperiod and vernalisation response of Mediterranean wheats, and implications for adaptation
Hexaploid wheat has the largest cultivated area among crop plants due to its adaptability to different agroclimatic regions. A large part of this adaptability depends upon the variation in vernalisation and photoperiod requirements. A better understanding of the genetic control of flowering in wheat, as expressed by vernalisation requirements and photoperiod response, will guide breeders in targeting crosses of different types and will also improve our understanding of regional adaptation requirements. Characterisation of large numbers of breeding lines for photoperiod and vernalisation response in wheat is needed to assign the lines to geographic areas of most probable adaptation. Simple screening methods to quantify the effects of these two factors and their interaction are needed to assist breeding progress. Twenty wheat lines were evaluated for response to photoperiod and vernalisation under two controlled environments and under high ambient air temperatures in field conditions. Vernalised and non vernalised seedlings were transplanted into pots and placed in three photoperiod (8, 12 and 16 h light) cabinets, in the greenhouse or in growth chambers. Days to anthesis decreased with increasing length of photoperiod. Vernalised plants flowered earlier than non vernalised plants. There was a significant correlation between days to anthesis in the greenhouse and the growth chamber (r=0.88, P<0.001). Length of basal vegetative period, effects of vernalisation, and photoperiod from the two screening techniques were positively correlated with each other. Growth habit score, vernalisation requirement and heading date in the field were highly correlated with the main effect of vernalisation in the two controlled environments. The results indicated that selection for vernalisation response in a large number of genotypes can be achieved under high ambient air temperatures in the field. The selected material can subsequently be screened for photoperiod response under greenhouse conditions. Using these techniques, 49 local and improved cultivars from the Mediterranean region in west Asia and north Africa (WANA), showing differences in response to photoperiod, vernalisation, and earliness independent of vernalisation and photoperiod, affecting time to anthesis, were identified. Most old local cultivars were sensitive to both photoperiod and vernalisation. All the improved genotypes were insensitive to photoperiod. Responses to vernalisation were generally small under short photoperiods, but were more pronounced in long photoperiod, particularly in winter and facultative types from northern latitudes. These results should help to explain the adaptability of cultivars based on photoperiod and vernalisation requirements and their interactio
Effect of unesterified cholesterol on the activity of cholesteryl ester transfer protein
Forward Neutron Production at the Fermilab Main Injector
We have measured cross sections for forward neutron production from a variety
of targets using proton beams from the Fermilab Main Injector. Measurements
were performed for proton beam momenta of 58 GeV/c, 84 GeV/c, and 120 GeV/c.
The cross section dependence on the atomic weight (A) of the targets was found
to vary as where is for a beam momentum of
58 GeV/c and 0.540.05 for 120 GeV/c. The cross sections show reasonable
agreement with FLUKA and DPMJET Monte Carlos. Comparisons have also been made
with the LAQGSM Monte Carlo.Comment: Accepted for publication in Physical Review D. This version
incorporates small changes suggested by referee and small corrections in the
neutron production cross sections predicted by FLUK
Measurement of Charged Pion Production Yields off the NuMI Target
The fixed-target MIPP experiment, Fermilab E907, was designed to measure the
production of hadrons from the collisions of hadrons of momenta ranging from 5
to 120 GeV/c on a variety of nuclei. These data will generally improve the
simulation of particle detectors and predictions of particle beam fluxes at
accelerators. The spectrometer momentum resolution is between 3 and 4%, and
particle identification is performed for particles ranging between 0.3 and 80
GeV/c using , time-of-flight and Cherenkov radiation measurements. MIPP
collected events of 120 GeV Main Injector protons striking a
target used in the NuMI facility at Fermilab. The data have been analyzed and
we present here charged pion yields per proton-on-target determined in bins of
longitudinal and transverse momentum between 0.5 and 80 GeV/c, with combined
statistical and systematic relative uncertainties between 5 and 10%.Comment: 15 pages, 13 figure
Isolation of a high-density-lipoprotein conversion factor from human plasma. A possible role of apolipoprotein A-IV as its activator
Breast cancer genetic counseling among Dutch patients from Turkish and Moroccan descent: participation determinants and perspectives of patients and healthcare professionals
Characterisation of the muon beams for the Muon Ionisation Cooling Experiment
A novel single-particle technique to measure emittance has been developed and used to characterise seventeen different muon beams for the Muon Ionisation Cooling Experiment (MICE). The muon beams, whose mean momenta vary from 171 to 281 MeV/c, have emittances of approximately 1.2–2.3 π mm-rad horizontally and 0.6–1.0 π mm-rad vertically, a horizontal dispersion of 90–190 mm and momentum spreads of about 25 MeV/c. There is reasonable agreement between the measured parameters of the beams and the results of simulations. The beams are found to meet the requirements of MICE
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