5,057 research outputs found
Intestinal Effects of Dietary Betaine in Piglets
The study was conducted to investigate the effects of graded dietary inclusion levels
of betaine on ileal and total tract nutrient digestibilities and intestinal bacterial fermentation
characteristics in piglets. A total of 8 barrows (BW 7.9 kg) was fitted with simple T-cannulas at the
distal ileum. The animals were randomly allocated to 1 of the 4 assay diets with 2 pigs per treatment in
4 repeated measurement periods. The assay diets included a basal diet based on wheat, barley and
soybean meal alone, or supplemented with a liquid betaine product at dietary levels of 1.5, 3.0, or 6.0
g betaine kg–1
diet (as–fed). Ileal digestibilities of dry matter (DM) and neutral detergent fiber (NDF)
increased both quadratically and linearly (P<0.05), and ileal digestibility of glycine increased linearly
as dietary betaine level increased (P<0.05). Moreover, there were linear increases in the concentrations
of ileal D–lactic acid (P<0.05), indicating intensified intestinal bacterial activities as dietary betaine
level increased. At the fecal level, total tract crude protein (CP) digestibility increased quadratically
(P<0.05), and digestibility of amino acids (AA) tended to increase quadratically (P=0.06 to P=0.11),
except for proline (P>0.05), as dietary betaine level increased. The increased bacterial degradation of
CP and AA in the large intestine coincides with the linear increase (P<0.05) in fecal diaminopimelic
acid concentrations, indicating enhanced intestinal bacterial growth with increasing dietary betaine
levels. In most cases, there was a response in the variables that were measured up to 3.0 g betaine per
kg diet, whereas increasing the betaine level from 3.0 to 6.0 g betaine per kg diet had no additional
effect. It can be concluded that dietary betaine stimulates microbial fermentation of fiber in the small
intestine, leaving less fermentable fiber to reach the large intestine and therefore, increased microbial
degradation of protein in the large intestine may occur.
Keywords: piglets, betaine, digestibility, bacterial fermentation, microflor
Betaine, organic acids and inulin do not affect ileal and total tract nutrient digestibility or microbial fermentation in piglets
The study was conducted to investigate the effects of betaine alone or combined with organic acids and inulin on ileal and total tract nutrient digestibilities and intestinal microbial fermentation characteristics in piglets. In total, 24 four-week-old barrows with an average initial body weight of 6.7 kg were used in two consecutive experiments with 12 piglets each. Betaine, organic acids and inulin at a level of 0.2, 0.4 and 0.2%, respectively, or combinations of these supplements were added to the basal diet. The supplementation of betaine, organic acids and inulin or any of their combinations did not affect ileal and total tract nutrient digestibilities. The microbial fermentation products both at the ileal and faecal level were not affected by any of the treatments. In conclusion, combining betaine with organic acids and inulin did not have any associated effects on the variables that were measured
Effect of graded levels of dietary betaine on ileal and total tract nutrient digestibilities and intestinal bacterial metabolites in piglets*
The study was conducted to investigate the effects of graded dietary
inclusion levels of betaine on ileal and total tract nutrient digestibilities
and intestinal bacterial metabolites in piglets. A total of eight barrows
with an average initial body weight of 7.9 kg were randomly allocated
to one of the four assay diets with two pigs per treatment in four
repeated measurement periods. The assay diets included a basal diet
based on wheat, barley and soybean meal alone, or supplemented with
a liquid betaine product at dietary levels of 1.5, 3.0, or 6.0 g betaine per
kilogram diet (as-fed). Ileal digestibilities of dry matter and neutral
detergent fibre increased both quadratically and linearly, and ileal
digestibility of glycine increased linearly as dietary betaine level
increased (p < 0.05). Furthermore, total tract digestibility of crude pro-
tein increased quadratically (p < 0.05) and total tract digestibilities of
most amino acids tended to increase quadratically (p = 0.06 to p = 0.11)
with increasing dietary betaine level. Moreover, there were linear
increases in the concentrations of most bacterial metabolites which were
significant p < 0.05 for ileal d-lactic acid and for faecal diaminopimelic
acid. The results demonstrate that dietary betaine supplementation stim-
ulates bacterial fermentation of fibre in the small intestine and bacterial
degradation of crude protein in the large intestine
Quantification of Strand Accessibility in Biostable DNA Origami with Single-Staple Resolution
DNA-based nanostructures are actively gaining interest as tools for biomedical and therapeutic applications following the recent development of protective coating strategies prolonging structural integrity in physiological conditions. For tailored biological action, these nanostructures are often functionalized with targeting or imaging labels using DNA base pairing. Only if these labels are accessible on the structure's surface will they be able to interact with their intended biological target. However, the accessibility of functional sites for different geometries and environments, specifically after the application of a protective coating, is currently not known. Here, we assay this accessibility on the level of single handle strands with two- and three-dimensional resolution using DNA-PAINT and show that the hybridization kinetics of top and bottom sides on the same nanostructure linked to a surface remain unaltered. We furthermore demonstrate that the functionality of the structures remains available after an oligolysine-PEG coating is applied, enabling bioassays where functionality and stability are imperative
Social physique anxiety and physical activity in early adolescent girls : the influence of maturation and physical activity motives
This study considered the influence of maturation on social physique anxiety (SPA), the relationship between SPA and current and future physical activity (PA) levels and the influence of motives for physical activity on this relationship in early adolescent girls (n=162; mean age=11.80±0.33 years). Participants completed the Pubertal Development Scale, the modified Social Physique Anxiety Scale and the Motives for Physical Activity Scale at baseline and the Physical Activity Questionnaire for Older Children at baseline and 6 months later. The girls became less active across the 6 months and girls in the early stages of maturation had significantly lower SPA than the girls in the middle and late stages of maturation. SPA was not related to current or future physical activity in the sample as a whole. Cluster analysis identified four groups with different motive profiles and the High Appearance and Fitness group demonstrated a moderate negative relationship between SPA and PA at phase 1, whereas the other groups did not. These findings indicate that SPA may increase with maturation and the relationship between SPA and PA is dependent on reasons for being active. For girls who are motivated to be active primarily by body-related reasons SPA is likely to lead to lower levels of PA
Direct observation and imaging of a spin-wave soliton with like symmetry
The prediction and realization of magnetic excitations driven by electrical
currents via the spin transfer torque effect, enables novel magnetic
nano-devices where spin-waves can be used to process and store information. The
functional control of such devices relies on understanding the properties of
non-linear spin-wave excitations. It has been demonstrated that spin waves can
show both an itinerant character, but also appear as localized solitons. So
far, it was assumed that localized solitons have essentially cylindrical,
like symmetry. Using a newly developed high-sensitivity time-resolved
magnetic x-ray microscopy, we instead observe the emergence of a novel
localized soliton excitation with a nodal line, i.e. with like symmetry.
Micromagnetic simulations identify the physical mechanism that controls the
transition from to like solitons. Our results suggest a potential new
pathway to design artificial atoms with tunable dynamical states using
nanoscale magnetic devices
Reversible Fluorination of Graphene: towards a Two-Dimensional Wide Bandgap Semiconductor
We report the synthesis and evidence of graphene fluoride, a two-dimensional
wide bandgap semiconductor derived from graphene. Graphene fluoride exhibits
hexagonal crystalline order and strongly insulating behavior with resistance
exceeding 10 G at room temperature. Electron transport in graphene
fluoride is well described by variable-range hopping in two dimensions due to
the presence of localized states in the band gap. Graphene obtained through the
reduction of graphene fluoride is highly conductive, exhibiting a resistivity
of less than 100 k at room temperature. Our approach provides a new
path to reversibly engineer the band structure and conductivity of graphene for
electronic and optical applications.Comment: 7 pages, 5 figures, revtex, to appear in PR
Edge pixel response studies of edgeless silicon sensor technology for pixellated imaging detectors
Silicon sensor technologies with reduced dead area at the sensor's perimeter are under development at a number of institutes. Several fabrication methods for sensors which are sensitive close to the physical edge of the device are under investigation utilising techniques such as active-edges, passivated edges and current-terminating rings. Such technologies offer the goal of a seamlessly tiled detection surface with minimum dead space between the individual modules. In order to quantify the performance of different geometries and different bulk and implant types, characterisation of several sensors fabricated using active-edge technology were performed at the B16 beam line of the Diamond Light Source. The sensors were fabricated by VTT and bump-bonded to Timepix ROICs. They were 100 and 200 μ m thick sensors, with the last pixel-to-edge distance of either 50 or 100 μ m. The sensors were fabricated as either n-on-n or n-on-p type devices. Using 15 keV monochromatic X-rays with a beam spot of 2.5 μ m, the performance at the outer edge and corners pixels of the sensors was evaluated at three bias voltages. The results indicate a significant change in the charge collection properties between the edge and 5th (up to 275 μ m) from edge pixel for the 200 μ m thick n-on-n sensor. The edge pixel performance of the 100 μ m thick n-on-p sensors is affected only for the last two pixels (up to 110 μ m) subject to biasing conditions. Imaging characteristics of all sensor types investigated are stable over time and the non-uniformities can be minimised by flat-field corrections. The results from the synchrotron tests combined with lab measurements are presented along with an explanation of the observed effects
Electronic structure investigation of Ti3AlC2, Ti3SiC2, and Ti3GeC2 by soft-X-ray emission spectroscopy
The electronic structures of epitaxially grown films of Ti3AlC2, Ti3SiC2 and
Ti3GeC2 have been investigated by bulk-sensitive soft X-ray emission
spectroscopy. The measured high-resolution Ti L, C K, Al L, Si L and Ge M
emission spectra are compared with ab initio density-functional theory
including core-to-valence dipole matrix elements. A qualitative agreement
between experiment and theory is obtained. A weak covalent Ti-Al bond is
manifested by a pronounced shoulder in the Ti L-emission of Ti3AlC2. As Al is
replaced with Si or Ge, the shoulder disappears. For the buried Al and
Si-layers, strongly hybridized spectral shapes are detected in Ti3AlC2 and
Ti3SiC2, respectively. As a result of relaxation of the crystal structure and
the increased charge-transfer from Ti to C, the Ti-C bonding is strengthened.
The differences between the electronic structures are discussed in relation to
the bonding in the nanolaminates and the corresponding change of materials
properties.Comment: 15 pages, 8 figure
- …