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

WOODLAND POND SALAMANDER ABUNDANCE IN RELATION TO FOREST MANAGEMENT AND ENVIRONMENTAL CONDITIONS IN NORTHERN WISCONSIN

Woodland ponds are important landscape features that help sustain populations of amphibians that require this aquatic habitat for successful reproduction. Species abundance patterns often reflect site-specific differences in hydrology, physical characteristics, and surrounding vegetation. Large-scale processes such as changing land cover and environmental conditions are other potential drivers influencing amphibian populations in the Upper Midwest, but little information exists on the combined effects of these factors. We used Blue-spotted (Ambystoma laterale Hallowell) and Spotted Salamander (A. maculatum Shaw) monitoring data collected at the same woodland ponds thirteen years apart to determine if changing environmental conditions and vegetation cover in surrounding landscapes influenced salamander movement phenology and abundance. Four woodland ponds in northern Wisconsin were sampled for salamanders in April 1992-1994 and 2005-2007. While Bluespotted Salamanders were more abundant than Spotted Salamanders in all ponds, there was no change in the numbers of either species over the years. However, peak numbers of Blue-spotted Salamanders occurred 11.7 days earlier (range: 9-14 days) in the 2000s compared to the 1990s; Spotted Salamanders occurred 9.5 days earlier (range: 3 - 13 days). Air and water temperatures (April 13- 24) increased, on average, 4.8 oC and 3.7 oC, respectively, between the decades regardless of pond. There were no discernible changes in canopy openness in surrounding forests between decades that would have warmed the water sooner (i.e., more light penetration). Our finding that salamander breeding phenology can vary by roughly 10 days in Wisconsin contributes to growing evidence that amphibian populations have responded to changing climate conditions by shifting life-cycle events. Managers can use this information to adjust monitoring programs and forest management activities in the surrounding landscape to avoid vulnerable amphibian movement periods. Considering direct and indirect stressors such as changing habitat and environmental conditions simultaneously to better understand trends in space and time can help improve monitoring programs for this taxa, which is at major risk of continued declines

Dirac points with giant spin-orbit splitting in the electronic structure of two-dimensional transition-metal carbides

Two-dimensional (2D) materials, especially their most prominent member, graphene, have greatly influenced many scientific areas. Moreover, they have become a base for investigating the relativistic properties of condensed matter within the emerging field of Dirac physics. This has ignited an intense search for new materials where charge carriers behave as massless or massive Dirac fermions. Here, we theoretically show the existence of Dirac electrons in a series of 2D transition-metal carbides, known as MXenes. They possess twelve conical crossings in the 1st Brillouin zone with giant spin-orbit splitting. Our findings indicate that the 2D band structure of MXenes is protected against external perturbations and preserved even in multilayer phases. These results, together with the broad possibilities to engineer the properties of these materials phases, make Dirac MXenes a potential candidate for studying and developing novel Dirac-physics-based technologies.Comment: 4 figures and supplementar

Sugar consumption and caries risk in schoolchildren with low caries experience

– This paper assesses the risk from sugar consumption in a population of schoolchildren with low caries experience. It relates eight different measures of sugar consumption to the occurrence of any DMFS increment, and, separately, to approximal and pit-and-fissure DMFS. The data are from a 3-yr longitudinal study of 429 children, initially aged 11–15, residing in non-fluoridated rural communities in Michigan, USA. All children completed at least three dietary interviews, were present for baseline and final dental examinations, and had a parent or guardian provide questionnaire information on residence history, use of fluoride and dental services, and family history. Results indicated that a higher proportion of total energy intake from sugars increased the probability of caries on all surfaces, and a higher total intake of sugars was also associated with total caries increment. No relationship, however, was found between DMFS increment and the frequency of eating high sugar foods. Each additional 5 g of daily sugars intake was associated with a 1% increase in the probability of developing caries, and those whose energy intake from sugars was 1 SD above the mean had 2.0 times the risk of developing approximal caries than did children whose energy intake from sugars was 1 SD below the mean.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74862/1/j.1600-0528.1995.tb00218.x.pd

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

Validity of Two Methods for Assessing Oral Health Status of Populations

Objective : This investigation assessed two methods for estimating epidemiologic indicators of oral health status among children: (1) a visual-only screening, performed independently by a dental hygienist and a registered nurse; and (2) a parent- or guardian-completed questionnaire. The indicators included dichotomous variables measuring dental caries and treatment needs, presence of sealants, injuries to the anterior teeth, and dental fluorosis. Methods : Following training and calibration, data were collected over an eight-day period in April 1994 among 632 elementary schoolchildren (aged 5 to 12 years) in Monticello, Georgia. Both screening and questionnaire findings were compared pairwise with results from visual-tactile examinations done by a dentist. Validity, represented by sensitivity, specificity, and predictive values, was assessed for screening results from the dental hygienist, the nurse, and the parent-completed questionnaire. Results : Validity was high for screening for caries and treatment needs (>90% for sensitivity, specificity, and predictive values in a sample having 30% to 40% prevalence). Less valid data — mainly an effect of false negatives — were obtained for fluorosis, injuries, and presence of sealants. No significant difference in validity was observed between the nurse and the dental hygienist. One-third of respondents to the questionnaire did not know if their children needed fillings (a proxy for untreated decay) or had received sealants; only knowledge of restorations was comparable to results from screening. Intraexaminer reliability for the two screeners ranged from 85 to 100 for percent agreement and 0.70 to 0.93 for kappa scores. Conclusions : Screening by dental hygienists or nurses can provide valid data for surveillance of dental caries and treatment needs. Training for visual assessment of fluorosis and injuries must be improved to diminish the proportion of false negatives. A parent-completed questionnaire is less effective than visual screening for evaluating oral health status in children.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66163/1/j.1752-7325.1997.tb02977.x.pd

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