3-way Interactions Research Articles

Interactions between sleep duration and quality as predictors of adolescents' adjustment

ObjectivesWe examined interactions between adolescents' sleep duration and quality as predictors of their internalizing symptoms and externalizing behaviors. As a secondary aim, we assessed adolescent sex, race/ethnicity, and socioeconomic status (SES) as additional moderators of risk (ie, 3-way interactions among sleep duration; quality; and sex, race, or SES). DesignThe study used a cross-sectional design. SettingParticipants were from small towns and semirural communities in Alabama. ParticipantsThe sample consisted of 235 adolescents (Mage = 15.78 years, SD = 9.60 months) and was diverse with respect to sex (54% female), race/ethnicity (32% Black/African American, 67% White), and SES. MeasurementsSleep duration (actual sleep minutes) was examined with actigraphs for 1 week. Adolescents reported on their subjective sleep quality, internalizing symptoms, and externalizing behavior with psychometrically sound measures. ResultsFindings revealed interactions between sleep duration and sleep quality as predictors of adolescents' adjustment. Adolescents with both short sleep duration in conjunction with poor sleep quality had the highest levels of internalizing symptoms and aggressive and rule-breaking behavior. SES interacted with sleep duration and sleep quality to predict rule-breaking behavior, and the highest level of problems was observed for adolescents from lower-SES homes who had short sleep duration accompanied by poor sleep quality. ConclusionsFindings identify the conjoint role of sleep duration and quality as predictors of adolescents' socioemotional adjustment and emphasize the importance of examining multiple sleep parameters simultaneously toward a better understanding of adaptation in adolescence.

The Effects of Low-Volume, High-Intensity Training on Performance Parameters in Competitive Youth Swimmers.

To assess the effects of a 7-wk low-volume, high-intensity training (HIT) intervention on performance parameters in national-level youth swimmers. Sixteen swimmers (age 15.8 [1.0]y, age at peak height velocity 12.9 [0.6]y, 100-m freestyle 61.4 [4.1]s) were randomly assigned to an HIT group or a low-intensity, high-volume training (HVT) group that acted as a control. The HIT group reduced their weekly training volume of zone 1 (low-intensity) training by 50% but increased zone 3 (high-intensity) training by 200%. The HVT group performed training as normal. Pretest to posttest measures of physiological performance (velocity at 2.5- and 4-mM blood lactate [velocity2.5mM and velocity4mM] and peak blood lactate), biomechanical performance (stroke rate, stroke length [SL], and stroke index [SI] over a 50- and 400-m freestyle), and swimming performance (50-, 200-, and 400-m freestyle) were assessed. There were no significant 3-way interactions between time, group, and sex for all performance parameters (P > .05). There was a significant 2-way interaction between time and group for velocity4mM (P = .02, ), SL50 (P = .03, ), and SI50 (P = .03, ). Velocity4mM decreased in the HIT group but increased in the HVT group while SL50 and SI50 decreased in the HVT group. A 7-wk HIT intervention was neither beneficial nor detrimental to performance parameters; however, the HIT group completed 6 h (17.0 km) of swimming per week compared with 12 h (33.4km) per week for the HVT group.

Effects of Iron Fortification on Fatty Acid Profiles of Caprine Milk Cheddar Cheeses under Different Storage Treatment Regimens

Three types of caprine milk Cheddar cheeses as non-fortified control cheese (CC), regular ferrous sulfate (RFS) and large microencapsulated ferrous sulfate (LMFS) fortified cheeses were manufactured in three batches each to evaluate effects of iron addition on fatty acid compositions of two iron fortified cheeses compared to those of CC cheese. All manufactured experimental cheeses were subjected to storage treatments of two temperatures (4 and -18°C) and three periods (0, 2, and 4 months). Fatty acid profiles of the experimental cheeses were quantified using a gas chromatograph equipped with a fused silica capillary column, flame ionization detector, AOC-20s auto sampler and AOC-20i auto injector. Results showed that cheese type significantly (p<0.05 or p<0.01) affected levels of most fatty acids, except for C10:0, C14:1, C16:1, C18:1, and C20:0 acids, indicating that fatty acid contents of iron fortified cheeses were generally higher than control cheese especially at 4 months of storage. The level of C16:0 was highest, followed by C18:1, C18:0 and C10:0 acid, respectively, in all three types of the experimental goat milk cheeses for all storage treatment regimens. The main factors of cheese type, storage temperature and time had significant influences on several different fatty acids, and some of the 2-way and 3-way interactions also showed significant effects on levels of different fatty acids. It was concluded that iron fortification, storage temperature and period had significant influences on the levels of majority of tested fatty acids in the experimental caprine milk Cheddar cheeses.

Belief about seat belt use and seat belt wearing behavior among front and rear seat passengers in the United States

Introduction: Unrestrained drivers and passengers represent almost half of all passenger vehicle occupant deaths in the United States. The current study assessed the relationship between the belief about importance of seat belt use and the behavior of always wearing a seat belt. Method: Data from 2012 ConsumerStyles were analyzed separately for front and rear passenger seating positions. Multivariable regression models were constructed to identify the association between seat belt belief and behavior (i.e., always wears seat belt) among adults. Models controlled for type of state seat belt law (primary, secondary, or none). Results: Seat belt use was higher in front passenger seats (86.1%) than in rear passenger seats (61.6%). Similarly, belief that seat belt use was very important was higher in reference to the front passenger seat (84.2%) versus the rear passenger seat (70.5%). For the front passenger seat, belief was significantly associated with seat belt use in states with both primary enforcement laws (adjPR 1.64) and secondary enforcement laws (adjPR 2.77). For the rear passenger seat, belief was also significantly associated with seat belt use, and two 2-way interactions were observed (belief by sex, belief by region). Conclusions: Despite overall high rates of seat belt use in the United States, certain groups are less likely to buckle up than others. The study findings suggest that efforts to increase seat belt use among high-risk populations, such as those who live in states with secondary or no seat belt laws and those who ride in rear seats (which include people who utilize taxis or ride-hailing vehicles) could benefit from interventions designed to strengthen beliefs related to the benefits of seat belt use. Practical applications: Future research that uses a theoretical framework to better understand the relationship between beliefs and behavior may inform interventions to improve seat belt use.

Interpersonal-level discrimination indices, sociodemographic factors, and telomere length in African-Americans and Whites

ObjectiveStudies have linked self-reported discrimination to telomere attrition, a biological marker of accelerated cellular aging. However, it is unknown whether intersections between social categories—race, socioeconomic status (SES), sex, and age—influence the association of varying forms of discrimination with telomere length. We examined these associations in a socioeconomically and racially/ethnically diverse urban sample. MethodsCross-sectional data were from 341 middle-aged (30–64 years) African American and White, community participants in the Healthy Aging in Neighborhoods of Diversity across the Life Span Study (HANDLS). Multiple regression models examined up to 3-way interactions between a discrimination measure (i.e., everyday, racial, gender, lifetime burden, and frequency of discrimination across sources) and two social categories. ResultsAfter adjusting for depressive symptoms, waist circumference, and lifetime substance use, two themes emerged: 1) among women with higher SES, a) greater lifetime discrimination burden (b = -0.23, p = .011), gender discrimination (b = -0.29, p = .040), and racial discrimination (b = -0.24, p = 0.023) and 2) among younger adults, irrespective of race and sex, greater frequency of discrimination across sources (b = 0.002, p = .008) was associated with shorter telomeres. ConclusionsIrrespective of race, women with higher SES and younger adults reporting greater discrimination may be at particular risk for accelerated aging. Telomere attrition promotes and accelerates chronic health conditions for which there are health disparities. Future research explicating intersections among specific discrimination indices and social categories is warranted.

57 Effects of particle size and heat treatment on in situ and in vitro digestion of dry-rolled Enogen® Feed Corn.

Enogen Feed Corn (EFC; Syngenta Seeds, LLC) has amplified expression of heat-stable amylase. Our objectives were to evaluate impacts of particle size and heat treatment on digestibility of EFC using a 4 x 4 x 3 factorial treatment arrangement. Mill-run corn (CON) and EFC were ground in a Wiley Mill through 9-, 6-, and 4-mm screens. CON and EFC were then blended to produce mixtures of 0, 33.3, 66.7, or 100% EFC. Duplicate samples were heated in a forced-air oven to internal temperatures of 50, 75, or 100oC, and a non-heated control also was used. In situ dry matter disappearance (14 h; ISDMD) was measured in triplicate using 6 fistulated steers. In vitro gas production (IVGP) and volatile fatty acid (VFA) profiles were measured in duplicate after incubating for 24 h at 39oC using fermentation bottles equipped with pressure sensing modules (ANKOM Technology, Macedon, NY). Production of VFA was measured by gas chromatography. There were no 2- or 3-way interactions (P > 0.10). ISDMD, IVGP, and concentrations of propionate and butyrate increased linearly in response to decreasing particle size (P 0.16). ISDMD and IVGP increased linearly in response to increasing proportions of EFC (Table 1), but VFA production was not affected by proportion of EFC. Enogen Feed Corn is more susceptible to degradation by ruminal microbes compared to non-Enogen corn, but absence of a quadratic response suggests that its impact on other dietary components is minimal. Open in a separate window

Abortion and other risk factors for mastitis in Iranian dairy herds

This paper forms a part of a series of studies aiming to estimate the costs of abortion in Iranian dairy herds. In previous studies we have determined mastitis as a significant risk factor for abortion. In order to provide a more reliable estimation of the costs associated with abortion in Iranian dairy herds, the risk of a cow getting infected with mastitis needs to be included. Data from 6 commercial herds and 32,191 cows was assigned to 3-weeks in milk (3-WIM) records from 1 to 567 d after calving (1st–27th 3-WIM). The effect of herd, parity, calving season, past incidence of abortion, cumulative FCM yield level (CFCML), past incidence of mastitis in previous 3-WIM periods (EMAS), days in milk (DIM) and their significant 2-way interactions on mastitis in current 3-WIM period (MAS) were evaluated using a logistic regression model. Mastitis rate (MR) in studied herds was on average 28.3%. Results show that herd, parity, EMAS, CFCML, calving season, and lactation stage significantly (P < 0.01) influenced the risk of MAS. The risk of MAS increased with lactation number. Cows with EMAS had 4.98 times greater risk of MAS compared to cows with no EMAS. Additionally, cows with medium-level CFCML (i.e. 2, 3, and 4) had a higher risk of MAS compared to cows on level 1 and 5. Calving during the spring significantly (P < 0.01) increased the risk of MAS compared to other seasons. Past incidence of abortion, however, was not significantly associated with MAS, but remained in the final model because of the interaction with other factors.It can be concluded that a risk factor analysis with all significant interactions is more informative than a model without the interactions, especially when making the optimal decision for a cow with given characteristics. Moreover, knowledge on the effect of influential factors on mastitis will be useful when designing mastitis control programs at herd or national level.

Interactions of dietary fiber bound antioxidants with hydroxycinnamic and hydroxybenzoic acids in aqueous and liposome media.

The interactions between dietary fiber (DF)-bound antioxidants and free antioxidants, with different substitution patterns of -OH and -OCH3 groups on their aromatic rings has been investigated. The activity and efficiency of these interactions were examined with a structural approach. Whole wheat (WW) DF-bound antioxidants and 21 hydroxycinnamic acid/hydroxybenzoic acids (HCA/HBA) were used in the experimental studies. Studies were performed in liposome and aqueous media by monitoring lipid oxidation and scavenging of DPPH radical in the presence of WW-bound antioxidants and HCA/HBA derivatives. Predominantly synergistic interactions were observed in aqueous medium, while both synergistic and antagonistic interactions were seen in liposome medium. Concentrations of HCA/HBA and WW-bound antioxidants in mixtures and their 2-way interactions made significant effect on lipid oxidation and radical scavenging reactions, with some exceptions. HCA/HBA derivatives with 3 ,4 -dihydroxyphenyl substitution acted as strong antioxidants in liposome medium, while the number of -OH groups affected antioxidant activity in aqueous medium.

Disentangling variables that influence growth response of balsam fir regeneration during a spruce budworm outbreak

Height increment of balsam fir (Abies balsamea (L.) Mill.) regeneration during a spruce budworm (Choristoneura fumiferana Clem.) outbreak can be affected by a variety of variables including defoliation, ground vegetation competition, canopy openness, the height of regeneration, and stand type. To disentangle how these variables interact to determine regeneration height increment, we sampled 36 plots in two regions showing contrasting climate, regional vegetation, and budworm outbreak severity. Linear mixed-effects models were used to analyze the effects of these five variables on height increment of balsam fir regeneration. In the Amqui (early defoliation) plots, height increment was significantly affected by a “cumulative defoliation × height of regeneration × hardwood content” interaction. Defoliation significantly reduced height increment when regeneration was >30 cm tall in softwood and mixedwood plots, but regeneration <30 cm tall in softwood and mixedwood plots and all regeneration in hardwood plots had light defoliation, which did not reduce height increment. Results were even more complex for the North Shore (late defoliation) plots, where there were three significant 3-way interactions affecting height increment: “height × hardwood content × ground vegetation cover”, “hardwood content × canopy openness × cumulative defoliation”, and “hardwood content × ground vegetation cover × cumulative defoliation”. Canopy openness was >25% in all softwood plots, and height increment substantially declined with increasing cumulative defoliation; however, in mixedwood and hardwood plots, canopy openness was <25% and height increment increased with defoliation. In softwood plots, height increment declined sharply with increasing cumulative defoliation at all ground vegetation cover levels, but in mixedwood and hardwood plots, height increment increased or decreased slightly with increasing cumulative defoliation. Results showed that the variables affecting height increment have surprisingly complex interactive effects.

Maternal Lifetime Trauma and Birthweight: Effect Modification by In Utero Cortisol and Child Sex

To evaluate associations between maternal lifetime traumatic stress and offspring birthweight and examine modifying effects of third trimester cortisol and fetal sex. Analyses included 314 mother-infant dyads from an ethnically mixed pregnancy cohort. Maternal lifetime trauma was reported via the Life Stressor Checklist-Revised. Fenton birthweight for gestational age z-scores (BWGA-z) were calculated. A 3-cm scalp-nearest maternal hair segment collected at birth was assayed to reflect cumulative third trimester cortisol secretion. Multivariable regression was used to investigate associations between maternal lifetime trauma and BWGA-z and examine 2- and 3-way interactions with cortisol and fetal sex. Because subjects with low or high cortisol levels could represent susceptible populations, varying coefficient models that relax the linearity assumption on cortisol level were used to assess the modification of maternal lifetime trauma associations with BWGA-z as a function of cortisol. Women were primarily minorities (41% Hispanic, 26% black) with ≤12 years education (63%); 63% reported ≥1 traumatic event. Prenatal cortisol modified the association between maternal lifetime trauma and birthweight. Women with higher lifetime trauma and increased cortisol had significantly lower birthweight infants in males; among males exposed to the 90th percentile of cortisol, a 1-unit increase in trauma score was associated with a 0.19-unit decrease in BWGA-z (95% CI, -0.34 to -0.04). Associations among females were nonsignificant, regardless of cortisol level. These findings underscore the need to consider complex interactions among maternal trauma, disrupted in utero cortisol production, and fetal sex to fully elucidate intergenerational effects of maternal lifetime trauma.

Autonomic nervous system coordination moderates links of negative interparental conflict with adolescent externalizing behaviors.

Although negative interparental conflict predicts elevated externalizing problems for children, there are individual differences in this association. Theoretically, children's abilities to coordinate physiological stress across response systems moderate the effects of interparental conflict on developmental outcomes. Past cross-sectional research has demonstrated that poor coordination of sympathetic (SNS) and parasympathetic (PNS) nervous systems puts children at a greater risk for externalizing behaviors in the context of interparental conflict. Our goal was to examine whether this same pattern is evident in adolescents and provide the first longitudinal test of this theoretical pathway. Participants were families with adolescents (10-17 years) from diverse ethnic and socioeconomic backgrounds. Parents reported conflict, were observed during a conflict discussion, and reported adolescent externalizing behaviors; parents again reported externalizing behaviors 1 year later. Adolescents experienced a stressor while skin conductance level (SCL; SNS) and respiratory sinus arrhythmia (RSA; PNS) were measured. Similar to past research with children, there were 3-way interactions between negative interparental conflict, SCL reactivity, and RSA reactivity in relation to adolescent externalizing behaviors, concurrently and prospectively. The overall pattern suggested that adolescents who displayed poorly coordinated responding displayed a positive association between interparental conflict and externalizing behaviors, whereas adolescents who showed well-coordinated responding displayed a nonsignificant or negative association. Coinhibition of the SNS and PNS may put adolescents particularly at risk for prospective externalizing behaviors. Autonomic nervous system coordination-particularly activation of the SNS and inhibition of the PNS during stress-may protect adolescents from experiencing adjustment problems in the context of interparental conflict. (PsycINFO Database Record

The Effects of Corporate Social Responsibility on Job Performance: Moderating Effects of Authentic Leadership and Meaningfulness of Work

The study aims to investigate methods for companies to contribute to not only social and national developments, but also on the promotion of individuals and companies by re-examining the various phenomena that define companies. The study examines the relationship between subordinate factors of social responsibility activities and job performances as well as the role of CEOs in showing authentic leadership and meaningfulness of work. A total of 312 valid questionnaires were obtained, and hypotheses were tested using regression analysis, hierarchical regression analysis, and 3-way interactions. The results suggest that corporate social responsibility activities not only enhanced the performance of the members, but also confirmed the importance of the authentic leadership of the CEO. Additionally, the role of the members in the company also showed to play a very significant role in a company’s developments. The results also show that the CEO and members need to make efforts to increase ethics as well as gain more competitiveness and improve their reputation by promoting their sense of calling and feeling of compassion in the workplace. In other words, the members of the high-ranking book and the members of the relatively low position will have different degrees of information transfer and evaluation of the company policy may be different.

Effects of age and visual attention demands on optokinetic nystagmus suppression

IntroductionThe utility of optokinetic nystagmus suppression as an index of visual attention has been demonstrated; however, a gap exists in our understanding of the effects of aging on attentional division. The purpose of this study was to explore the effect of a subject's age upon their ability to allocate visual attention among multiple salient elements which varied in location and complexity. MethodLarge-field optokinetic nystagmus (OKN)-inducing animations were presented along with a central flashing fixation point to 27 subjects: 15 younger adults (range 19–23, mean age 21.4); and 12 older adults (range 65–89, mean age 74). Subjects were instructed to fixate on a central point while attending to either moving features of the background or solely to the fixation target. Failure of subjects to accurately divide their attention was quantified by optokinetic gain (eye velocity/background velocity). Gain was analysed in two separate 3-way ANOVAs: one at the central location with the between-subjects variable of age and within-subjects variables of complexity and dynamism; and one using only the dynamic tasks, including a between-subjects variable of age and within-subjects variables of complexity and location. ResultsA strong effect of age was found between subjects during the more attentionally demanding dynamic tasks, but there was only a marginal effect during the static tasks. All within-subjects variables were highly significant, and there were several significant 2- and 3-way interactions. ConclusionThis study provides strong evidence for the compounding effects of senescence and stimulus characteristics on an adult's ability to accurately allocate visual attention. These findings show that OKN suppression may be a useful framework for quantification of attentional resources in older subjects.

Four-year decline in Ostrea chilensis recruits per spawner in Foveaux Strait, New Zealand, suggests a diminishing stock-recruitment relationship

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 600:85-98 (2018) - DOI: https://doi.org/10.3354/meps12641 Four-year decline in Ostrea chilensis recruits per spawner in Foveaux Strait, New Zealand, suggests a diminishing stock-recruitment relationship Keith P. Michael1,2,3,*, Jeffrey S. Shima1,2 1School of Biological Sciences, Victoria University of Wellington, PO Box 600, Wellington 6140, New Zealand 2Victoria University Coastal Ecology Laboratory (VUCEL), PO Box 600, Wellington 6140, New Zealand 3National Institute of Water and Atmospheric Research (NIWA), PB 14901, Wellington 6021, New Zealand *Corresponding author: k.michael@niwa.co.nz ABSTRACT: Rebuilding and maintaining sufficient spawning stock to ensure recruitment is a key strategy for fisheries management and ecological restoration. We evaluated variation in Ostrea chilensis recruitment across seasons and sites over 4-6 yr in Foveaux Strait (New Zealand) to infer the relative importance of determinants of population recruitment. Recruitment varied significantly between seasons (p < 0.001). Most recruitment in any given year (97.8 ± 0.9%, mean ± SE) occurred in the austral spring and summer (November to February). Recruitment also varied significantly between years (p < 0.001). In a separate fishery-wide study, we investigated the effect of spawner densities on recruitment, relative to other climatic and biological factors. We deployed spat collectors at 6 sites across 3 discrete fishery areas, and estimated densities of spawning-sized oysters from dredge samples. We modelled counts of oyster spat and spawners with a negative binomial regression to evaluate the stock-recruitment relationship. Recruitment varied between years (50.8% of the deviance explained), spawner densities (13.8%), and areas (11.6%), with further 2-way interactions among these factors. Importantly, our analysis showed a continued decline in recruits per spawner, despite similar or increasing densities of spawning-sized oysters. Average recruitment for 2010-11 when spawner densities were highest was 4.6% of the level observed in 2007-08. Our data suggest that factors other than densities of oysters play a major role in the numbers of competent larvae available for settlement. Managing oyster fisheries as a single stock and maintaining oyster densities above management reference points alone may not be sufficient to ensure recruitment to rebuild populations. KEY WORDS: Recruitment variability · Oysters · Spatial management · Foveaux Strait · Stock-recruitment relationship Full text in pdf format Supplementary material PreviousNextCite this article as: Michael KP, Shima JS (2018) Four-year decline in Ostrea chilensis recruits per spawner in Foveaux Strait, New Zealand, suggests a diminishing stock-recruitment relationship. Mar Ecol Prog Ser 600:85-98. https://doi.org/10.3354/meps12641 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 600. Online publication date: July 30, 2018 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2018 Inter-Research.

Including the Ductal Carcinoma-In-Situ (DCIS) Score in the Development of a Multivariable Prediction Model for Recurrence After Excision of DCIS

IntroductionIndividual prediction of local recurrence (LR) risk after breast-conserving surgery (BCS) for ductal carcinoma-in-situ (DCIS) is needed to identify women at low risk, for whom radiotherapy may be omitted. Patients and MethodsThree predictive models of LR—clinicopathologic factors (CPF) alone; CPF + estrogen receptor (ER) + human epidermal growth factor receptor 2 (HER2); and CPF + DCIS score (DS)—were developed among 1102 cases of DCIS in patients with complete covariate and outcome data. Categorizations of discrete variables and transformations of continuous variables were examined in Cox models; 2-way interactions and interactions with time were assessed. Internal validation was performed by bootstrapping. Individual predicted 10-year LR risks were computed from covariate values, estimated regression parameters, and estimated baseline survival function. Accuracy was assessed by c statistics and calibration plots. ResultsThe strongest prediction model incorporated CPF + DS. The c statistics for CPF + DS, CPF + ER + HER2, or CPF-alone models were 0.7025, 0.6879, and 0.6825, respectively. The CPF + DS model was better calibrated at predicting low (≤ 10%) individual 10-year LR risks after BCS alone than those incorporating CPF + ER + HER2 or CPF alone, evidenced by c statistics and plots of observed by predicted risks. Among women aged ≥ 50 with no adverse CPF, the CPF + DS model identified the greatest proportion of women (62.3%) with predicted individual 10-year LR ≤ 10% without radiotherapy compared to the CPF + ER + HER2 (50.9%) or CPF alone (46.5%) models. ConclusionIndividual prediction of LR incorporating DS is more accurate and identifies a higher proportion of women with low predicted risk of LR after BCS alone, for whom radiotherapy may be omitted.

Benchmarking relief-based feature selection methods for bioinformatics data mining

Modern biomedical data mining requires feature selection methods that can (1) be applied to large scale feature spaces (e.g. ‘omics’ data), (2) function in noisy problems, (3) detect complex patterns of association (e.g. gene-gene interactions), (4) be flexibly adapted to various problem domains and data types (e.g. genetic variants, gene expression, and clinical data) and (5) are computationally tractable. To that end, this work examines a set of filter-style feature selection algorithms inspired by the ‘Relief’ algorithm, i.e. Relief-Based algorithms (RBAs). We implement and expand these RBAs in an open source framework called ReBATE (Relief-Based Algorithm Training Environment). We apply a comprehensive genetic simulation study comparing existing RBAs, a proposed RBA called MultiSURF, and other established feature selection methods, over a variety of problems. The results of this study (1) support the assertion that RBAs are particularly flexible, efficient, and powerful feature selection methods that differentiate relevant features having univariate, multivariate, epistatic, or heterogeneous associations, (2) confirm the efficacy of expansions for classification vs. regression, discrete vs. continuous features, missing data, multiple classes, or class imbalance, (3) identify previously unknown limitations of specific RBAs, and (4) suggest that while MultiSURF∗ performs best for explicitly identifying pure 2-way interactions, MultiSURF yields the most reliable feature selection performance across a wide range of problem types.

Effect of phytase, carbohydrase, and protease addition to a wheat distillers dried grains with solubles and rapeseed based diet on in vitro ileal digestibility, growth, and bone mineral density of grower-finisher pigs

The use of rapeseed meal (RSM) and wheat distillers dried grains with solubles (wDDGS) in pig diets is increasing and dietary supplementation with exogenous enzymes has been suggested as means of improving feed efficiency in pigs. The objective of this experiment was to examine the effect of phytase (Phy), a xylanase and β-glucanase complex (XB), protease (Prot) and their various combinations when included in a wDDGS- and RSM-based diet fed to grower-finisher pigs. As the P- and Ca- sparing effect of Phy is well proven, the objective was to examine the additional effects of Phy beyond its P- and Ca-sparing effects. A total of 144 pigs with an initial live weight of 40.1 ± 2.0 kg were assigned to 8 treatments with 9 pens (4 female and 5 male pens) per treatment and 2 females or 2 males per pen. The basal diet was formulated to contain 96 and 200 g/kg of RSM and wDDGS, respectively. The basal diet was supplemented with Phy (0 or 100 mg/kg), XB (0 or 100 mg/kg), and Prot (0 or 200 mg/kg) in a 2 × 2 × 2 factorial arrangement of treatments. Experimental diets were fed for 76 d. Average daily gain (ADG) and average daily feed intake (ADFI) were recorded, and gain to feed (G:F) was calculated. Carcass quality variables were measured at slaughter and the left forelimb of pigs fed the unsupplemented, the Phy supplemented and the Phy + Prot supplemented diets were removed to determine bone mineral density in the third metacarpal. The inclusion of Phy, XB and Prot in the diets increased in vitro ileal digestibility of dry matter and organic matter (P < 0.05). A tendency towards a 3-way interaction among Phy, XB and Prot was observed for ADG (P = 0.06) and G:F (P = 0.06). The 2-way interactions and main effects did not reveal any improvement for any variable measured in vivo in response to dietary enzyme supplementation. Bone mineral density was not different for pigs fed the unsupplemented, the Phy supplemented and the Phy + Prot supplemented diets. In conclusion, the in vitro ileal digestibility improvements observed were not always reflected in improvements in pig growth, feed efficiency or both. The efficacy of Phy was not reduced when supplemented in combination with Prot, as ADG, G:F, carcass quality and bone mineralization were unchanged.

Hen genetic strain and extended cold storage influence on physical egg quality from cage-free aviary housing system

In the United States, there is an increase in need for cage-free eggs in retail and food manufacturing sectors. Understanding the impact of cage-free systems and the corresponding management on egg quality is pertinent as the U.S. industry adapts existing housing and builds new cage-free housing structures. A study was conducted comparing 2 brown shell and 2 white shell hen strains housed in a cage-free aviary system. Each set of eggs were placed in cold storage and assessed at 0, 2, 4, 8, and 12 wk. Eggs were collected at 21, 31, 42, and 60 wk of hen age. A full profile of physical quality measurements was conducted on up to 18 intact eggs for each hen strain/egg storage/hen age combination. Egg weight increased approximately 10g for brown shell and 14g for white shell eggs as hens aged. Many of the properties monitored were significantly impacted by all 3 main effects (hen strain, egg storage, and hen age) resulting in 3-way interactions. A brown and a white shell strain had stronger shells (44N; P <0.0001) than the remaining brown and white shell strains (42N and 39N, respectively). The current study also determined volume of shell, total length, maximum width, and percent length at maximum width to more accurately indicate egg shape than shape index. One brown shell strain produced eggs with the most consistent shape characteristics over the hen ages monitored. White shell eggs from the cage-free aviary housing produced the highest whole-egg total solids between 31 to 60 wk of hen age, whereas brown shell eggs resulted in the most consistent level of whole-egg total solids (22-23.5%). The brown and white shell strains in the current study produce cage-free aviary eggs with distinctive physical quality attributes. The outcomes from this study can be utilized by the U.S. egg industry in planning management strategies and market placement of cage-free eggs.

Multiple-stressor effects of sediment, phosphorus and nitrogen on stream macroinvertebrate communities

Multiple stressors affect stream ecosystems worldwide and their interactions are of particular concern, with gaps existing in understanding stressor impacts on stream communities. Addressing these knowledge gaps will aid in targeting and designing of appropriate mitigation measures. In this study, the agricultural stressors fine sediment (ambient, low, medium, high), phosphorus (ambient, enriched) and nitrogen (ambient, enriched) were manipulated simultaneously in 64 streamside mesocosms to determine their individual and combined effects on the macroinvertebrate community (benthos and drift). Stressor levels were chosen to reflect those typically observed in European agricultural streams. A 21-day colonisation period was followed by a 14-day manipulative period. Results indicate that added sediment had the most pervasive effects, significantly reducing total macroinvertebrate abundance, total EPT abundance and abundances of three common EPT taxa. The greatest effect was at high sediment cover (90%), with decreasing negative impacts at medium (50%) and low (30%) covers. Added sediment also led to higher drift propensities for nine of the twelve drift variables. The effects of nitrogen and phosphorus were relatively weak compared to sediment. Several complex and unpredictable 2-way or 3-way interactions among stressors were observed. While sediment addition generally reduced total abundance at high levels, this decrease was amplified by P enrichment at low sediment, whereas the opposite effect occurred at medium sediment and little effect at high sediment. These results have direct implications for water management as they highlight the importance of managing sediment inputs while also considering the complex interactions which can occur between sediment and nutrient stressors.

Free-Weight Resistance Exercise Versus Weight Machines on Pulse Wave Reflection

Acute resistance exercise (ARE) has a large effect on pulse wave reflection, but the data are limited when examining these responses after free-weight (FW) versus weight-machine (WM) exercises. PURPOSE: To evaluate alterations in pulse wave reflection after FW exercise compared to WM exercise in resistance-trained individuals. METHODS: Individuals volunteered to participate in either FW (n=25) or WM (n=16) resistance exercises. Data were collected at rest, and 10-15min after ARE. The FW group completed 3 sets of 10 repetitions at 75% 1-repetition maximum (1RM) on the squat, bench press and deadlift, while the WM group completed 3 sets of 10 repetitions at 75%1RM on the leg press, lat pulldown, leg extension, chest press, and the leg curl. A 2x2x2 analysis of covariance (ANCOVA) was used to analyze the effects of group (FW, WM) across condition (ARE, control) and time (rest, recovery) with workload as a covariate. RESULTS: The groups were similar for anthropometrics (p>0.05), but differed in years spent training (FW: 7±4 yrs; WM: 4±2 yrs, p=0.0001). There were no differences at rest for any measures of pulse wave reflection. Neither group nor condition had an effect on brachial or aortic blood pressure. There was a significant 3-way interaction for heart rate (FW: rest: 59±8bpm, recovery: 88±13bpm; WM: rest: 65±9bpm, recovery: 89±13bpm, p=0.04) such that it was augmented during recovery from resistance exercise in the FW group compared to the WM group. There were also significant 3-way interactions for the augmentation index (FW: rest: 116±8.4%, recovery:121.2±9.5%; WM: rest: 116.8±8.4%, recovery: 113.7±5.5%, p=0.006), augmentation pressure (FW: rest: 5.0±2.9mmHg, recovery: 8.4±5.9mmHg; WM: rest: 4.3±4.0mmHg, recovery: 3.8±3.6mmHg, p=0.029), and the augmentation index normalized at 75bpm (FW: rest: 4.9±8.1%, recovery: 24.1±14.5%; WM: rest: 8.7±12.3%, recovery: 16.8±8.2%, p=0.015) such that they were increased in the FW group compared to the WM group during recovery from ARE, which differed from the control. CONCLUSION: These data demonstrate that recovery from free-weight resistance exercises has significant effects on pulse wave reflection that supersede those of weight machine resistance exercises in resistance-trained individuals, despite no differences in brachial or aortic blood pressures.