Glucose absorption, carbohydrase activities, and carbohydrate hydrolysis and uptake in the intestinal tract of mature sheep

Carbohydrates are the predominant source of energy used to carry out the biological processes of growth, maintenance, and reproduction in the animal body. Glucose is the most important carbohydrate metabolite in both the nonruminant and the ruminant animal. In the non ruminant, glucose is also the most abundant end product of carbohydrate digestion. The nonruminant is able to utilize only traces of cellulose and hemicellulose as end products of microbial degradation in the large intestine, and the small intestine of this animal is the major site of carbohydrate assimilation. The microbiological digestion of carbohydrates makes the reticulo-nimen and to a lesser extent the omasum the major sites of carbohydrate assimilation in the ruminant animal. These microorganisms also degrade a portion of cellulose and hemicellulose to absorbable end products which can be utilized by the host animal. The rumen, being the major site of carbohydrate assimilation, has received the greatest attention by investigators of protein, fat, and carbohydrate utilization in the ruminant. Some research has been conducted in an attempt to determine the ability of the pre weaned ruminant to utilize certain carbohydrates. Little information is available in the literature regarding the digestion of carbohydrates and the absorption of glucose in the small and large intestine of the mature ruminant animal. In advanced pregnancy and during lactation an animal is in a critical glucose balance resulting from lactose synthesis (Armstrong, 1965). Since the major precursor of lactose is blood glucose (Reiss and Barry, 1953) supplied primarily through gluconeogenesis of noncarbohydrate sources (Armstrong, 1965), the importance of any glucose absorbed from the gastro-intestinal tract which would contribute directly to the maintenance of the blood glucose level is obvious. Although it is estimated that only about 10 percent of the glucose requirement of the ruminant animal is absorbed from the alimentary tract (Armstrong, 1965), it is of interest to know the efficiency of glucose absorption and utilization of other carbohydrates in the small and large intestine of the mature ruminant. The objectives of these studies were to determine; (l) the levels of the carbohydrases, maltase, lactase, sucrase, amylase, and cellobiase in the mucosa of the duodenum, jejunum, and ileum; (2) the rate of absorption of glucose in vivo in the duodenum, jejunum, ileum, cecum, and colon; and (3) the degree of utilization of maltose, starch, and cellulose in the duodenum, jejunum, ileum, cecum, and colon in mature sheep

Predictors of change in global psychiatric functioning at an inpatient adolescent psychiatric unit: A decade of experience

BACKGROUND: Psychiatric inpatient treatment for children is sometimes beneficial, but predictors of who benefits, and in what circumstances, are largely unknown. This study aimed to identify personal and environmental factors that influence outcome in an adolescent unit that accepts both emergency and planned admissions. METHODS: Routine standardised intake and outcome measures were analysed for the period 2009–2018. Potential predictors assessed included the Children’s Global Assessment Scale (CGAS), engagement with treatment, behavioural attitudes and peer relationships on the unit. FINDINGS: One hundred and twelve admissions were tracked. Mean age of admission was 16 years, and 71% were female. A total of 61% had higher (better) CGAS scores on discharge than on admission; 34% of inpatients fully engaged with their treatment. Median admission duration was 118 days for males and 196 days for females. Admission lengths were much shorter for ethnic minority patients, but group sizes were small. Longer admissions led to greater improvement. Poor outcomes were associated with failure to engage with treatment and a deterioration in peer relationships. INTERPRETATION: Compliance with treatment and female gender were both significant predictors of positive change during admission. The establishment of good and supportive peer relationships during the admission was also a potent indicator of benefit

Predictors of change in global psychiatric functioning at an inpatient adolescent psychiatric unit: A decade of experience

Background: Psychiatric inpatient treatment for children is sometimes beneficial, but predictors of who benefits, and in what circumstances, are largely unknown. This study aimed to identify personal and environmental factors that influence outcome in an adolescent unit that accepts both emergency and planned admissions. Methods: Routine standardised intake and outcome measures were analysed for the period 2009–2018. Potential predictors assessed included the Children’s Global Assessment Scale (CGAS), engagement with treatment, behavioural attitudes and peer relationships on the unit. Findings: One hundred and twelve admissions were tracked. Mean age of admission was 16 years, and 71% were female. A total of 61% had higher (better) CGAS scores on discharge than on admission; 34% of inpatients fully engaged with their treatment. Median admission duration was 118 days for males and 196 days for females. Admission lengths were much shorter for ethnic minority patients, but group sizes were small. Longer admissions led to greater improvement. Poor outcomes were associated with failure to engage with treatment and a deterioration in peer relationships. Interpretation: Compliance with treatment and female gender were both significant predictors of positive change during admission. The establishment of good and supportive peer relationships during the admission was also a potent indicator of benefit

Operational characteristics of mixed-format multistage tests using the 3PL testlet response theory model

textMultistage tests (MSTs) have received renewed interest in recent years as an effective compromise between fixed-length linear tests and computerized adaptive test. Most MSTs studies scored the assessments based on item response theory (IRT) methods. Many assessments are currently being developed as mixed-format assessments that administer both standalone items and clusters of items associated with a common stimulus called testlets. By the nature of a testlet, a natural dependency occurs between the items within the testlet that violates the local independence of items. Local independence is a fundamental assumption of the IRT models. Using dichotomous IRT methods on a mixed-format testlet-based assessment knowingly violates local independence. By combining the score points within a testlet, researchers have successfully applied polytomous IRT models. However, the use of such models loses information by not using the unique response patterns provided by each item within a testlet. The three-parameter logistic testlet response theory (3PL-TRT) model is a measurement model developed to retain the uniqueness in response patterns of each item, while accounting for the local dependency exhibited by a testlet, or testlet effect. Because few studies have examined mixed-format MSTs administration under the 3PL-TRT model, the dissertation performed a simulation to investigate the administration of a mixed-format testlet based MSTs under the 3PL-TRT model. Simulee responses were generated based on the 3PL-TRT calibrated item parameters from a real large-scale passage based standardized assessment. The manipulated testing conditions considered four panel designs, two test lengths, three routing procedures, and three conditions of local item dependence. The study found functionally no bias across testing conditions. All conditions showed adequate measurement properties, but a few differences did occur between some of the testing conditions. The measurement precision was impacted by panel design, test length and the magnitude of local item dependence. The three-stage MSTs consistently illustrated slightly lower measurement precision than the two-stage MSTs. As expected, the longer test length conditions had better measurement precision than the shorter test length conditions. Conditions with the largest magnitude of local item dependency showed the worst measurement precision. The routing procedure had little impact on the measurement effectiveness.Educational Psycholog

Conflicting Selection in the Course of Adaptive Diversification: The Interplay between Mutualism and Intraspecific Competition

Adaptive speciation can occur when a population undergoes assortative mating and disruptive selection caused by frequency-dependent intraspecific competition. However, other interactions, such as mutualisms based on trait matching, may generate conflicting selective pressures that constrain species diversification. We used individual-based simulations to explore how different types of mutualism affect adaptive diversification. A magic trait was assumed to simultaneously mediate mate choice, intraspecific competition, and mutualisms. In scenarios of intimate, specialized mu- tualisms, individuals interact with one or few individual mutualistic partners, and diversification is constrained only if the mutualism is obligate. In other scenarios, increasing numbers of different partners per individual limit diversification by generating stabilizing selection. Stabilizing selection emerges from the greater likelihood of trait mismatches for rare, extreme phenotypes than for common intermediate phenotypes. Constraints on diversification imposed by increased numbers of partners decrease if the trait matching degree has smaller positive effects on fitness. These results hold after the relaxation of various assumptions. When trait matching matters, mutualism-generated stabilizing selection would thus often constrain diversification in obligate mutualisms, such as ant-myrmecophyte associations, and in low-intimacy mutualisms, including plant-seed disperser systems. Hence, different processes, such as trait convergence favoring the incorporation of nonrelated species, are needed to explain the higher richness of low-intimacy assemblages—shown here to be up to 1 order of magnitude richer than high-intimacy systems

Outcomes of inpatient psychiatric treatment for adolescents: A multiple perspectives evaluation

Adolescent inpatient psychiatric treatment was evaluated from the multiple perspectives of clinicians, young people and parents using standardised measures and goal-based outcomes (GBOs). The sample included cases (N = 128) discharged from a London adolescent unit between April 2009 and December 2015. Measures were completed at admission and discharge, and change in ratings was analysed to assess treatment outcomes. Ratings of clinicians and young people on the Health of the Nation Outcome Scales for Children and Adolescents (HoNOSCA) were compared. Adolescents demonstrated significant improvement across all measures from admission to discharge. Correlation between clinicians’ and adolescents’ HoNOSCA ratings was weak at admission (r = .25) but stronger at discharge (r = .63). Standardised effect sizes were larger for GBOs (d = 1.73 and 3.16 for adolescent and clinician-rated goals, respectively) compared to all standardised measures (d = 0.31–0.93). Improvement was observed across all measures of functioning and symptoms following inpatient treatment. Clinicians and young people developed better shared understanding of the problems from admission to discharge. GBOs are more sensitive to change compared to standardised measures and may be meaningfully adopted by inpatient units for routine outcome monitoring

A Network Perspective for Community Assembly

Species interactions are responsible for many key mechanisms that govern the dynamics of ecological communities. Variation in the way interactions are organized among species results in different network structures, which translates into a community's ability to resist collapse and change. To better understand the factors involved in dictating ongoing dynamics in a community at a given time, we must unravel how interactions affect the assembly process. Here, we build a novel, integrative conceptual model for understanding how ecological communities assemble that combines ecological networks and island biogeography theory, as well as the principles of niche theory. Through our conceptual model, we show how the rate of species turnover and gene flow within communities will influence the structure of ecological networks. We conduct a preliminary test of our predictions using plant-herbivore networks from differently-aged sites in the Hawaiian archipelago. Our approach will allow future modeling and empirical studies to develop a better understanding of the role of the assembly process in shaping patterns of biodiversity