Using factor analysis to identify neuromuscular synergies during treadmill walking

NASA Technical Reports Server (NTRS)

Merkle, L. A.; Layne, C. S.; Bloomberg, J. J.; Zhang, J. J.

1998-01-01

Neuroscientists are often interested in grouping variables to facilitate understanding of a particular phenomenon. Factor analysis is a powerful statistical technique that groups variables into conceptually meaningful clusters, but remains underutilized by neuroscience researchers presumably due to its complicated concepts and procedures. This paper illustrates an application of factor analysis to identify coordinated patterns of whole-body muscle activation during treadmill walking. Ten male subjects walked on a treadmill (6.4 km/h) for 20 s during which surface electromyographic (EMG) activity was obtained from the left side sternocleidomastoid, neck extensors, erector spinae, and right side biceps femoris, rectus femoris, tibialis anterior, and medial gastrocnemius. Factor analysis revealed 65% of the variance of seven muscles sampled aligned with two orthogonal factors, labeled 'transition control' and 'loading'. These two factors describe coordinated patterns of muscular activity across body segments that would not be evident by evaluating individual muscle patterns. The results show that factor analysis can be effectively used to explore relationships among muscle patterns across all body segments to increase understanding of the complex coordination necessary for smooth and efficient locomotion. We encourage neuroscientists to consider using factor analysis to identify coordinated patterns of neuromuscular activation that would be obscured using more traditional EMG analyses.

Rotation Criteria and Hypothesis Testing for Exploratory Factor Analysis: Implications for Factor Pattern Loadings and Interfactor Correlations

ERIC Educational Resources Information Center

Schmitt, Thomas A.; Sass, Daniel A.

2011-01-01

Exploratory factor analysis (EFA) has long been used in the social sciences to depict the relationships between variables/items and latent traits. Researchers face many choices when using EFA, including the choice of rotation criterion, which can be difficult given that few research articles have discussed and/or demonstrated their differences.…

Previously identified patellar tendinopathy risk factors differ between elite and sub-elite volleyball players.

PubMed

Janssen, I; Steele, J R; Munro, B J; Brown, N A T

2015-06-01

Patellar tendinopathy is the most common knee injury incurred in volleyball, with its prevalence in elite athletes more than three times that of their sub-elite counterparts. The purpose of this study was to determine whether patellar tendinopathy risk factors differed between elite and sub-elite male volleyball players. Nine elite and nine sub-elite male volleyball players performed a lateral stop-jump block movement. Maximum vertical jump, training history, muscle extensibility and strength, three-dimensional landing kinematics (250 Hz), along with lower limb neuromuscular activation patterns (1500 Hz), and patellar tendon loading were collected during each trial. Multivariate analyses of variance (P < 0.05) assessed for between-group differences in risk factors or patellar tendon loading. Significant interaction effects were further evaluated using post-hoc univariate analysis of variance tests. Landing kinematics, neuromuscular activation patterns, patellar tendon loading, and most of the previously identified risk factors did not differ between the elite and sub-elite players. However, elite players participated in a higher training volume and had less quadriceps extensibility than sub-elite players. Therefore, high training volume is likely the primary contributor to the injury discrepancy between elite and sub-elite volleyball players. Interventions designed to reduce landing frequency and improve quadriceps extensibility are recommended to reduce patellar tendinopathy prevalence in volleyball players. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Neurophysiological differences between patients clinically at high risk for schizophrenia and neurotypical controls--first steps in development of a biomarker.

PubMed

Duffy, Frank H; D'Angelo, Eugene; Rotenberg, Alexander; Gonzalez-Heydrich, Joseph

2015-11-02

Schizophrenia is a severe, disabling and prevalent mental disorder without cure and with a variable, incomplete pharmacotherapeutic response. Prior to onset in adolescence or young adulthood a prodromal period of abnormal symptoms lasting weeks to years has been identified and operationalized as clinically high risk (CHR) for schizophrenia. However, only a minority of subjects prospectively identified with CHR convert to schizophrenia, thereby limiting enthusiasm for early intervention(s). This study utilized objective resting electroencephalogram (EEG) quantification to determine whether CHR constitutes a cohesive entity and an evoked potential to assess CHR cortical auditory processing. This study constitutes an EEG-based quantitative neurophysiological comparison between two unmedicated subject groups: 35 neurotypical controls (CON) and 22 CHR patients. After artifact management, principal component analysis (PCA) identified EEG spectral and spectral coherence factors described by associated loading patterns. Discriminant function analysis (DFA) determined factors' discrimination success between subjects in the CON and CHR groups. Loading patterns on DFA-selected factors described CHR-specific spectral and coherence differences when compared to controls. The frequency modulated auditory evoked response (FMAER) explored functional CON-CHR differences within the superior temporal gyri. Variable reduction by PCA identified 40 coherence-based factors explaining 77.8% of the total variance and 40 spectral factors explaining 95.9% of the variance. DFA demonstrated significant CON-CHR group difference (P <0.00001) and successful jackknifed subject classification (CON, 85.7%; CHR, 86.4% correct). The population distribution plotted along the canonical discriminant variable was clearly bimodal. Coherence factors delineated loading patterns of altered connectivity primarily involving the bilateral posterior temporal electrodes. However, FMAER analysis showed no CON-CHR group differences. CHR subjects form a cohesive group, significantly separable from CON subjects by EEG-derived indices. Symptoms of CHR may relate to altered connectivity with the posterior temporal regions but not to primary auditory processing abnormalities within these regions.

[Spatial pattern of land surface dead combustible fuel load in Huzhong forest area in Great Xing'an Mountains].

PubMed

Liu, Zhi-Hua; Chang, Yu; Chen, Hong-Wei; Zhou, Rui; Jing, Guo-Zhi; Zhang, Hong-Xin; Zhang, Chang-Meng

2008-03-01

By using geo-statistics and based on time-lag classification standard, a comparative study was made on the land surface dead combustible fuels in Huzhong forest area in Great Xing'an Mountains. The results indicated that the first level land surface dead combustible fuel, i. e., 1 h time-lag dead fuel, presented stronger spatial auto-correlation, with an average of 762.35 g x m(-2) and contributing to 55.54% of the total load. Its determining factors were species composition and stand age. The second and third levels land surface dead combustible fuel, i. e., 10 h and 100 h time-lag dead fuels, had a sum of 610.26 g x m(-2), and presented weaker spatial auto-correlation than 1 h time-lag dead fuel. Their determining factor was the disturbance history of forest stand. The complexity and heterogeneity of the factors determining the quality and quantity of forest land surface dead combustible fuels were the main reasons for the relatively inaccurate interpolation. However, the utilization of field survey data coupled with geo-statistics could easily and accurately interpolate the spatial pattern of forest land surface dead combustible fuel loads, and indirectly provide a practical basis for forest management.

[Analysis of dietary pattern and diabetes mellitus influencing factors identified by classification tree model in adults of Fujian].

PubMed

Yu, F L; Ye, Y; Yan, Y S

2017-05-10

Objective: To find out the dietary patterns and explore the relationship between environmental factors (especially dietary patterns) and diabetes mellitus in the adults of Fujian. Methods: Multi-stage sampling method were used to survey residents aged ≥18 years by questionnaire, physical examination and laboratory detection in 10 disease surveillance points in Fujian. Factor analysis was used to identify the dietary patterns, while logistic regression model was applied to analyze relationship between dietary patterns and diabetes mellitus, and classification tree model was adopted to identify the influencing factors for diabetes mellitus. Results: There were four dietary patterns in the population, including meat, plant, high-quality protein, and fried food and beverages patterns. The result of logistic analysis showed that plant pattern, which has higher factor loading of fresh fruit-vegetables and cereal-tubers, was a protective factor for non-diabetes mellitus. The risk of diabetes mellitus in the population at T2 and T3 levels of factor score were 0.727 (95 %CI: 0.561-0.943) times and 0.736 (95 %CI : 0.573-0.944) times higher, respectively, than those whose factor score was in lowest quartile. Thirteen influencing factors and eleven group at high-risk for diabetes mellitus were identified by classification tree model. The influencing factors were dyslipidemia, age, family history of diabetes, hypertension, physical activity, career, sex, sedentary time, abdominal adiposity, BMI, marital status, sleep time and high-quality protein pattern. Conclusion: There is a close association between dietary patterns and diabetes mellitus. It is necessary to promote healthy and reasonable diet, strengthen the monitoring and control of blood lipids, blood pressure and body weight, and have good lifestyle for the prevention and control of diabetes mellitus.

The effect of mechanical loads on the degradation of aliphatic biodegradable polyesters.

PubMed

Li, Ying; Chu, Zhaowei; Li, Xiaoming; Ding, Xili; Guo, Meng; Zhao, Haoran; Yao, Jie; Wang, Lizhen; Cai, Qiang; Fan, Yubo

2017-06-01

Aliphatic biodegradable polyesters have been the most widely used synthetic polymers for developing biodegradable devices as alternatives for the currently used permanent medical devices. The performances during biodegradation process play crucial roles for final realization of their functions. Because physiological and biochemical environment in vivo significantly affects biodegradation process, large numbers of studies on effects of mechanical loads on the degradation of aliphatic biodegradable polyesters have been launched during last decades. In this review article, we discussed the mechanism of biodegradation and several different mechanical loads that have been reported to affect the biodegradation process. Other physiological and biochemical factors related to mechanical loads were also discussed. The mechanical load could change the conformational strain energy and morphology to weaken the stability of the polymer. Besides, the load and pattern could accelerate the loss of intrinsic mechanical properties of polymers. This indicated that investigations into effects of mechanical loads on the degradation should be indispensable. More combination condition of mechanical loads and multiple factors should be considered in order to keep the degradation rate controllable and evaluate the degradation process in vivo accurately. Only then can the degradable devise achieve the desired effects and further expand the special applications of aliphatic biodegradable polyesters.

Quasi-static and dynamic experimental studies on the tensile strength and failure pattern of concrete and mortar discs.

PubMed

Jin, Xiaochao; Hou, Cheng; Fan, Xueling; Lu, Chunsheng; Yang, Huawei; Shu, Xuefeng; Wang, Zhihua

2017-11-10

As concrete and mortar materials widely used in structural engineering may suffer dynamic loadings, studies on their mechanical properties under different strain rates are of great importance. In this paper, based on splitting tests of Brazilian discs, the tensile strength and failure pattern of concrete and mortar were investigated under quasi-static and dynamic loadings with a strain rate of 1-200 s -1 . It is shown that the quasi-static tensile strength of mortar is higher than that of concrete since coarse aggregates weaken the interface bonding strength of the latter. Numerical results confirmed that the plane stress hypothesis lead to a lower value tensile strength for the cylindrical specimens. With the increase of strain rates, dynamic tensile strengths of concrete and mortar significantly increase, and their failure patterns change form a single crack to multiple cracks and even fragment. Furthermore, a relationship between the dynamic increase factor and strain rate was established by using a linear fitting algorithm, which can be conveniently used to calculate the dynamic increase factor of concrete-like materials in engineering applications.

Well-being as a moving target: measurement equivalence of the Bradburn Affect Balance Scale.

PubMed

Maitland, S B; Dixon, R A; Hultsch, D F; Hertzog, C

2001-03-01

Although the Bradburn Affect Balance scale (ABS) is a frequently used two-factor indicator of well-being in later life, its measurement and invariance properties are not well documented. We examined these issues using confirmatory factor analyses of cross-sectional (adults ages 54-87 years) and longitudinal data from the Victoria Longitudinal Study. Stability of the positive and negative affect factors was moderate across a 3-year period. Overall, factor loadings for positive affect items were invariant over time with the exception of the pleased item. Negative affect items were time invariant. However, age-group comparisons between young-old and old-old groups revealed age differences in loadings for the upset item at Time 1. Finally, gender groups differed in loadings for the top of the world and going your way items. Thus a pattern of partial measurement equivalence characterized item response to the ABS. Our results suggest that group comparisons and longitudinal change in ABS scale scores of positive and negative affect should be interpreted with caution.

Validity Generalization of the WISC-R Factor Structure with 10 1/2-Year-Old Children.

ERIC Educational Resources Information Center

Shiek, David A.; Miller, John E.

1978-01-01

Investigated robustness of the Wechsler Intelligence Scale for Children-Revised (WISC-R) factor structure. Comparisons of the loadings obtained with generalization sample and 10 1/2-year-old national standardization sample suggest high degree of similarity in composition, magnitude, and pattern. Findings highly support robustness of WISC-R's…

What happens if we compare chopsticks with forks? The impact of making inappropriate comparisons in cross-cultural research.

PubMed

Chen, Fang Fang

2008-11-01

It is a common practice to export instruments developed in one culture to another. Little is known about the consequences of making inappropriate comparisons in cross-cultural research. Several studies were conducted to fill in this gap. Study 1 examined the impact of lacking factor loading invariance on regression slope comparisons. When factor loadings of a predictor are higher in the reference group (e.g., United States), for which the scale was developed, than in the focal group (e.g., China), into which the scale was imported, the predictive relationship (e.g., self-esteem predicting life satisfaction) is artificially stronger in the reference group but weaker in the focal group, creating a bogus interaction effect of predictor by group (e.g., self-esteem by culture); the opposite pattern is found when the reference group has higher loadings in an outcome variable. Studies 2 and 3 examined the impact of lacking loading and intercept (i.e., point of origin) invariance on factor means, respectively. When the reference group has higher loadings or intercepts, the mean is overestimated in that group but underestimated in the focal group, resulting in a pseudo group difference. (c) 2008 APA, all rights reserved.

Comparison of Deterministic and Probabilistic Radial Distribution Systems Load Flow

NASA Astrophysics Data System (ADS)

Gupta, Atma Ram; Kumar, Ashwani

2017-12-01

Distribution system network today is facing the challenge of meeting increased load demands from the industrial, commercial and residential sectors. The pattern of load is highly dependent on consumer behavior and temporal factors such as season of the year, day of the week or time of the day. For deterministic radial distribution load flow studies load is taken as constant. But, load varies continually with a high degree of uncertainty. So, there is a need to model probable realistic load. Monte-Carlo Simulation is used to model the probable realistic load by generating random values of active and reactive power load from the mean and standard deviation of the load and for solving a Deterministic Radial Load Flow with these values. The probabilistic solution is reconstructed from deterministic data obtained for each simulation. The main contribution of the work is: Finding impact of probable realistic ZIP load modeling on balanced radial distribution load flow. Finding impact of probable realistic ZIP load modeling on unbalanced radial distribution load flow. Compare the voltage profile and losses with probable realistic ZIP load modeling for balanced and unbalanced radial distribution load flow.

Interaction of Soil Heavy Metal Pollution with Industrialisation and the Landscape Pattern in Taiyuan City, China

PubMed Central

Liu, Yong; Su, Chao; Zhang, Hong; Li, Xiaoting; Pei, Jingfei

2014-01-01

Many studies indicated that industrialization and urbanization caused serious soil heavy metal pollution from industrialized age. However, fewer previous studies have conducted a combined analysis of the landscape pattern, urbanization, industrialization, and heavy metal pollution. This paper was aimed at exploring the relationships of heavy metals in the soil (Pb, Cu, Ni, As, Cd, Cr, Hg, and Zn) with landscape pattern, industrialisation, urbanisation in Taiyuan city using multivariate analysis. The multivariate analysis included correlation analysis, analysis of variance (ANOVA), independent-sample T test, and principal component analysis (PCA). Geographic information system (GIS) was also applied to determine the spatial distribution of the heavy metals. The spatial distribution maps showed that the heavy metal pollution of the soil was more serious in the centre of the study area. The results of the multivariate analysis indicated that the correlations among heavy metals were significant, and industrialisation could significantly affect the concentrations of some heavy metals. Landscape diversity showed a significant negative correlation with the heavy metal concentrations. The PCA showed that a two-factor model for heavy metal pollution, industrialisation, and the landscape pattern could effectively demonstrate the relationships between these variables. The model explained 86.71% of the total variance of the data. Moreover, the first factor was mainly loaded with the comprehensive pollution index (P), and the second factor was primarily loaded with landscape diversity and dominance (H and D). An ordination of 80 samples could show the pollution pattern of all the samples. The results revealed that local industrialisation caused heavy metal pollution of the soil, but such pollution could respond negatively to the landscape pattern. The results of the study could provide a basis for agricultural, suburban, and urban planning. PMID:25251460

Interaction of soil heavy metal pollution with industrialisation and the landscape pattern in Taiyuan city, China.

PubMed

Liu, Yong; Su, Chao; Zhang, Hong; Li, Xiaoting; Pei, Jingfei

2014-01-01

Many studies indicated that industrialization and urbanization caused serious soil heavy metal pollution from industrialized age. However, fewer previous studies have conducted a combined analysis of the landscape pattern, urbanization, industrialization, and heavy metal pollution. This paper was aimed at exploring the relationships of heavy metals in the soil (Pb, Cu, Ni, As, Cd, Cr, Hg, and Zn) with landscape pattern, industrialisation, urbanisation in Taiyuan city using multivariate analysis. The multivariate analysis included correlation analysis, analysis of variance (ANOVA), independent-sample T test, and principal component analysis (PCA). Geographic information system (GIS) was also applied to determine the spatial distribution of the heavy metals. The spatial distribution maps showed that the heavy metal pollution of the soil was more serious in the centre of the study area. The results of the multivariate analysis indicated that the correlations among heavy metals were significant, and industrialisation could significantly affect the concentrations of some heavy metals. Landscape diversity showed a significant negative correlation with the heavy metal concentrations. The PCA showed that a two-factor model for heavy metal pollution, industrialisation, and the landscape pattern could effectively demonstrate the relationships between these variables. The model explained 86.71% of the total variance of the data. Moreover, the first factor was mainly loaded with the comprehensive pollution index (P), and the second factor was primarily loaded with landscape diversity and dominance (H and D). An ordination of 80 samples could show the pollution pattern of all the samples. The results revealed that local industrialisation caused heavy metal pollution of the soil, but such pollution could respond negatively to the landscape pattern. The results of the study could provide a basis for agricultural, suburban, and urban planning.

The effects of control order, feedback, practice, and input device on tracking performance and perceived workload

NASA Technical Reports Server (NTRS)

Hancock, P. A.; Robinson, M. A.

1989-01-01

The present experiment examined the influence of several task-related factors on tracking performance and concomitant workload. The manipulated factors included tracking order, the presence or absence of knowledge of performance, and the control device. Summed root mean square error (rmse) and perceived workload were measured at the termination of each trial. Perceived workload was measured using the NASA Task Load Index (TLX) and the Subjective Workload Assessment Technique (SWAT). Results indicated a large and expected effect for track order on both performance and the perception of load. In general, trackball input was more accurate and judged for lower load than input using a mouse. The presence or absence of knowledge of performance had little effect on either performance or workload. There were a number of interactions between factors shown in performance that were mirrored by perceived workload scores. Results from each workload scale were equivalent in terms of sensitivity to task manipulations. The pattern of results affirm the utility of these workload measures in assessing the imposed load of multiple task-related variables.

Building America Case Study: The Impact of Thermostat Placement in Low-Load Homes in Sunny Climates, Denver, Colorado

DOE Office of Scientific and Technical Information (OSTI.GOV)

Modern, energy-efficient homes conforming to the Zero Energy Ready Home standard face the challenge of meeting high customer expectations for comfort. Traditional heating, ventilation, and air conditioning (HVAC) sizing and control strategies may be insufficient to adequately condition each zone due to unique load patterns in each room caused by a number of factors. These factors include solar heat gains, occupant-related gains, and gains associated with appliances and electronics. Because of shrinking shell loads, these intermittent factors are having an increasingly significant impact on the thermal load in each zone. Consequently, occupant comfort can be compromised. To evaluate the impactmore » of climate and house geometry, as well as HVAC system and control strategies on comfort conditions, IBACOS analyzed the results of 99 TRNSYS multiple-zone simulations. The results of this analysis indicate that for simple-geometry and single-story plans, a single zone and thermostat can adequately condition the entire house. Demanding house geometry and houses with multiple stories require the consideration of multiple thermostats and multiple zones.« less

Risk Assessment of Heating, Ventilating, and Air-Conditioning Strategies in Low-Load Homes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poerschke, Andrew

2016-02-17

"Modern, energy efficient homes conforming to the Zero Energy Ready Home standard face the challenge of meeting high customer expectations for comfort. Traditional heating, ventilation, and air conditioning (HVAC) sizing and control strategies may be insufficient to adequately condition each zone due to unique load patterns in each room caused by a number of factors. These factors include solar heat gains, occupant-related gains, and gains associated with appliances and electronics. Because of shrinking shell loads, these intermittent factors are having an increasingly significant impact on the thermal load in each zone. Consequently, occupant comfort can be compromised. To evaluate themore » impact of climate and house geometry, as well as HVAC system and control strategies on comfort conditions, IBACOS analyzed the results of 99 TRNSYS multiple-zone simulations. The results of this analysis indicate that for simple-geometry and single-story plans, a single zone and thermostat can adequately condition the entire house. Demanding house geometry and houses with multiple stories require the consideration of multiple thermostats and multiple zones.« less

Normalized spectral damage of a linear system over different spectral loading patterns

NASA Astrophysics Data System (ADS)

Kim, Chan-Jung

2017-08-01

Spectral fatigue damage is affected by different loading patterns; the damage may be accumulated in a different manner because the spectral pattern has an influence on stresses or strains. The normalization of spectral damage with respect to spectral loading acceleration is a novel solution to compare the accumulated fatigue damage over different spectral loading patterns. To evaluate the sensitivity of fatigue damage over different spectral loading cases, a simple notched specimen is used to conduct a uniaxial vibration test for two representative spectral patterns-random and harmonic-between 30 and 3000 Hz. The fatigue damage to the simple specimen is analyzed for different spectral loading cases using the normalized spectral damage from the measured response data for both acceleration and strain. The influence of spectral loading patterns is discussed based on these analyses.

Lubricant distribution and its effect on slider air bearing performance over bit patterned media disk of disk drives

NASA Astrophysics Data System (ADS)

Wu, Lin

2011-04-01

The distribution dynamics of a thin lubricant film on a bit-patterned media disk and its effect on the performance of the ultralow flying air bearing slider of disk drives are studied by direct numerical simulations. Our analysis shows that the physics governing lubricant distribution dynamics changes when deep enough sub-100-nm nanostructures are patterned on the disk surface. Air shearing under the slider that dominates lubricant flow on a flat disk may become negligible on a bit-patterned media disk. Surface tension and disjoining pressure become dominant factors instead. Our results show that disks with nanoscale patterns/roughness may no longer be treated as flat, and the air bearing load may strongly depend not only on the geometric detail of disk patterns but also on how lubricants are distributed on the patterns when slider-disk clearance is reduced to sub-10-nm. Air bearing load and consequently the slider's flying attitude are affected by disk pattern geometry, average lubricant thickness, and material properties of lubricant such as the surface tension coefficient and Hamaker constant. The significantly expanded parameter space, upon which ultralow flying slider's dynamics depends, has to be seriously considered in evaluating the head/disk interface tribology performance of next generation patterned media magnetic recording systems.

Effect of low or high glycemic load diets on experimentally induced mammary carcinogenesis in rats.

PubMed

Thompson, Henry J; Neuhouser, Marian L; Lampe, Johanna W; McGinley, John N; Neil, Elizabeth S; Schwartz, Yvonne; McTiernan, Anne

2016-06-01

High glycemic load diets have been associated with increased breast cancer risk in population-based studies, but the evidence is mixed. This investigation determined whether diets differing in glycemic load affected the carcinogenic process using a preclinical model. Human diets, formulated to differ 2-fold in glycemic load, were evaluated in the 1-methyl-nitrosourea-induced (37.5 mg/kg) mammary carcinogenesis model. Cancer incidence (23.3 versus 50.0%, p = 0.032), multiplicity, (0.40 versus 1.03, p = 0.030) and burden, (0.62 versus 1.19 g/rat, p = 0.037) were reduced in the low versus high glycemic load diets, respectively. However, the low glycemic protective effect was attenuated when two purified diets that differed in resistant starch and simulated the glycemic effects of the human diets were fed. Protection was associated with alterations in markers of cell growth regulation. Our findings show that human low or high glycemic load dietary patterns differentially affect the carcinogenic response in a nondiabetic rodent model for breast cancer. However, factors that are associated with these patterns, in addition to dietary carbohydrate availability, appear to account for the differences observed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The capacity-load model of non-communicable disease risk: understanding the effects of child malnutrition, ethnicity and the social determinants of health.

PubMed

Wells, Jonathan C K

2018-05-01

The capacity-load model is a conceptual model developed to improve understanding of the life-course aetiology of non-communicable diseases (NCDs) and their ecological and societal risk factors. The model addresses continuous associations of both (a) nutrition and growth patterns in early life and (b) lifestyle factors at older ages with NCD risk. Metabolic capacity refers to physiological traits strongly contingent on early nutrition and growth during the first 1000 days, which promote the long-term capacity for homeostasis in the context of fuel metabolism and cardiovascular health. Metabolic load refers to components of nutritional status and lifestyle that challenge homeostasis. The higher the load, and the lower the capacity, the greater the NCD risk. The model therefore helps understand dose-response associations of both early development and later phenotype with NCD risk. Infancy represents a critical developmental period, during which slow growth can constrain metabolic capacity, whereas rapid weight gain may elevate metabolic load. Severe acute malnutrition in early childhood (stunting, wasting) may continue to deplete metabolic capacity, and confer elevated susceptibility to NCDs in the long term. The model can be applied to associations of NCD risk with socio-economic position (SEP): lower SEP is generally associated with lower capacity but often also with elevated load. The model can also help explain ethnic differences in NCD risk, as both early growth patterns and later body composition differ systematically between ethnic groups. Recent work has begun to clarify the role of organ development in metabolic capacity, which may further contribute to ethnic differences in NCD risk.

Bayesian Factor Analysis as a Variable Selection Problem: Alternative Priors and Consequences

PubMed Central

Lu, Zhao-Hua; Chow, Sy-Miin; Loken, Eric

2016-01-01

Factor analysis is a popular statistical technique for multivariate data analysis. Developments in the structural equation modeling framework have enabled the use of hybrid confirmatory/exploratory approaches in which factor loading structures can be explored relatively flexibly within a confirmatory factor analysis (CFA) framework. Recently, a Bayesian structural equation modeling (BSEM) approach (Muthén & Asparouhov, 2012) has been proposed as a way to explore the presence of cross-loadings in CFA models. We show that the issue of determining factor loading patterns may be formulated as a Bayesian variable selection problem in which Muthén and Asparouhov’s approach can be regarded as a BSEM approach with ridge regression prior (BSEM-RP). We propose another Bayesian approach, denoted herein as the Bayesian structural equation modeling with spike and slab prior (BSEM-SSP), which serves as a one-stage alternative to the BSEM-RP. We review the theoretical advantages and disadvantages of both approaches and compare their empirical performance relative to two modification indices-based approaches and exploratory factor analysis with target rotation. A teacher stress scale data set (Byrne, 2012; Pettegrew & Wolf, 1982) is used to demonstrate our approach. PMID:27314566

Research reactor loading pattern optimization using estimation of distribution algorithms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiang, S.; Ziver, K.; AMCG Group, RM Consultants, Abingdon

2006-07-01

A new evolutionary search based approach for solving the nuclear reactor loading pattern optimization problems is presented based on the Estimation of Distribution Algorithms. The optimization technique developed is then applied to the maximization of the effective multiplication factor (K{sub eff}) of the Imperial College CONSORT research reactor (the last remaining civilian research reactor in the United Kingdom). A new elitism-guided searching strategy has been developed and applied to improve the local convergence together with some problem-dependent information based on the 'stand-alone K{sub eff} with fuel coupling calculations. A comparison study between the EDAs and a Genetic Algorithm with Heuristicmore » Tie Breaking Crossover operator has shown that the new algorithm is efficient and robust. (authors)« less

Dietary patterns using the Food Guide Pyramid groups are associated with sociodemographic and lifestyle factors: the multiethnic cohort study.

PubMed

Park, Song-Yi; Murphy, Suzanne P; Wilkens, Lynne R; Yamamoto, Jennifer F; Sharma, Sangita; Hankin, Jean H; Henderson, Brian E; Kolonel, Laurence N

2005-04-01

Dietary patterns have been used to identify typical combinations of foods that may be associated with disease risks. We defined dietary patterns among 195,298 participants of the Multiethnic Cohort Study in Hawaii and Los Angeles in 1993-1996. Intakes of Food Guide Pyramid groups were calculated from a quantitative FFQ for subjects of 5 ethnic groups (African Americans, Hawaiians, Japanese Americans, Latinos, and whites). Three distinct dietary patterns, "Fat and Meat," "Vegetables," and "Fruit and Milk," were identified by exploratory factor analysis with a varimax rotation and validated by confirmatory factor analysis. Similar factor loadings were found for each of 10 ethnic-gender groups in stratified analyses. The odds ratios (OR) for being above the median scores for each factor were calculated. Age, gender, and ethnicity had relatively strong associations with dietary patterns whereas education showed only weak associations. BMI > or = 30 was strongly positively associated with the Fat and Meat pattern (OR = 2.14, 95% CI: 2.08-2.20, vs. BMI < 25). Current smokers showed a positive association with the Fat and Meat pattern (OR = 1.67, CI: 1.62-1.72, vs. nonsmokers) and inverse associations with the Vegetables (OR = 0.66, CI: 0.64-0.68) and Fruit and Milk patterns (OR = 0.53, CI: 0.52-0.55). Physical activity was positively associated with the Vegetables and Fruit and Milk patterns but not with the Fat and Meat pattern. These findings support the hypothesis that dietary patterns are influenced by interrelated sociocultural, demographic, and other lifestyle factors and may be useful in investigations of diet-disease relations.

Do dietary patterns determine levels of vitamin B6, folate, and vitamin B12 intake and corresponding biomarkers in European adolescents? The Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study.

PubMed

Iglesia, Iris; Huybrechts, Inge; Mouratidou, Theodora; Santabárbara, Javier; Fernández-Alvira, Juan M; Santaliestra-Pasías, Alba M; Manios, Yannis; De la O Puerta, Alejandro; Kafatos, Anthony; Gottrand, Frédéric; Marcos, Ascensión; Sette, Stefania; Plada, Maria; Stehle, Peter; Molnár, Dénes; Widhalm, Kurt; Kersting, Mathilde; De Henauw, Stefaan; Moreno, Luis A; González-Gross, Marcela

2018-06-01

To determine dietary patterns (DPs) and explain the highest variance of vitamin B 6 , folate, and B 12 intake and related concentrations among European adolescents. A total of 2173 adolescents who participated in the Healthy Lifestyle in Europe by Nutrition in Adolescence study met the eligibility criteria for the vitamin B intake analysis (46% boys) and 586 adolescents for the biomarkers analysis (47% boys). Two non-consecutive, 24-h, dietary recalls were used to assess the mean intakes. Concentrations were measured by chromatography and immunoassay testing. A reduced rank regression was applied to elucidate the combined effect of food intake of vitamin B and related concentrations. The identified DPs (one per vitamin B intake and biomarker and by sex) explained a variability between 34.2% and 23.7% of the vitamin B intake and between 17.2% and 7% of the biomarkers. In the reduced rank regression models, fish, eggs, cheese, whole milk and buttermilk intakes were loaded positively for vitamin B intake in both sexes; however, soft drinks and chocolate were loaded negatively. For the biomarkers, a higher variability was observed in the patterns in terms of food loads such as alcoholic drinks, sugars, and soft drinks. Some food items were loaded differently between intakes and biomarkers such as fish products, which was loaded positively for intakes but negatively for plasma folate in girls. The identified DPs explained up to 34.2% and 17.2% of the variability of the vitamin B intake and plasma concentrations, respectively, in European adolescents. Further studies are needed to elucidate the factors that determine such patterns. Copyright © 2017 Elsevier Inc. All rights reserved.

Analysis of surface cracks in finite plates under tension or bending loads

NASA Technical Reports Server (NTRS)

Newman, J. C., Jr.; Raju, I. S.

1979-01-01

Stress-intensity factors calculated with a three-dimensional, finite-element analysis for shallow and deep semielliptical surface cracks in finite elastic isotropic plates subjected to tension or bending loads are presented. A wide range of configuration parameters was investigated. The ratio of crack depth to plate thickness ranged from 0.2 to 0.8 and the ratio of crack depth to crack length ranged from 0.2 to 2.0. The effects of plate width on stress-intensity variations along the crack front was also investigated. A wide-range equation for stress-intensity factors along the crack front as a function of crack depth, crack length, plate thickness, and plate width was developed for tension and bending loads. The equation was used to predict patterns of surface-crack growth under tension or bending fatigue loads. A modified form of the equation was also used to correlate surface-crack fracture data for a brittle epoxy material within + or - 10 percent for a wide range of crack shapes and crack sizes.

Gender differences in the relationship between hostility and the type A behavior pattern.

PubMed

McCann, B S; Woolfolk, R L; Lehrer, P M; Schwarcz, L

1987-01-01

A group of 97 male and 111 female undergraduates completed the Jenkins Activity Survey, the Framingham Type A Scale, the Adjective Checklist Type A Scale, the Spielberger State-Trait Anxiety Inventory, and the Buss-Durkee Hostility Inventory. A factor analysis revealed three dimensions: Anger-Emotionality, Anger-Aggression, and Residual Pattern A. All Type A measures loaded highly on the Type A factor, with the Jenkins Activity Survey loading the highest. The Framingham Type A Scale was related to Anger-Emotionality, the Adjective Checklist Type A Scale was related to Anger-Aggression, and the Jenkins Activity Survey was related to neither of the anger dimensions. Women scored higher than men on Anger-Emotionality and the Guilt, Resentment, and Irritability subscales and lower than men on the Assaultiveness subscale. Women showed higher correlations between Type A and the Guilt subscale, and men between Type A and the Suspiciousness subscale. We conclude that Type A is a multidimensional construct that manifests itself differently in men and women.

Association between healthy maternal dietary pattern and risk for gestational diabetes mellitus.

PubMed

Tryggvadottir, E A; Medek, H; Birgisdottir, B E; Geirsson, R T; Gunnarsdottir, I

2016-02-01

Gestational diabetes mellitus (GDM) is associated with negative health effects for mother and child. The aim was to investigate the association between maternal dietary patterns and GDM. Prospective observational study including 168 pregnant women aged 18-40 years, recruited at routine 20-week ultrasound. All participants kept a 4-day weighed food record following recruitment (commencement: gestational weeks 19-24). Principal component analysis was used to extract dietary patterns from 29 food groups. A Healthy Eating Index (HEI) was constructed. All women underwent an oral glucose tolerance test in weeks 23-28. One clear dietary pattern (Eigenvalue 2.4) was extracted with positive factor loadings for seafood; eggs; vegetables; fruits and berries; vegetable oils; nuts and seeds; pasta; breakfast cereals; and coffee, tea and cocoa powder, and negative factor loadings for soft drinks and French fries. This pattern was labeled a prudent dietary pattern. Explained variance was 8.2%. The prevalence of GDM was 2.3% among women of normal weight before pregnancy (n=86) and 18.3% among overweight/obese women (n=82). The prudent dietary pattern was associated with lower risk of GDM (OR: 0.54; 95% CI: 0.30, 0.98). When adjusting for age, parity, prepregnancy weight, energy intake, weekly weight gain and total metabolic equivalent of task the association remained (OR: 0.36; 95% CI: 0.14, 0.94). Similar results were found when only including overweight or obese women (OR: 0.31; 95% CI: 0.13, 0.75). Adhering to a prudent dietary pattern in pregnancy was clearly associated with lower risk of GDM, especially among women already at higher risk because of overweight/obesity before pregnancy.

Selected Contribution: Skeletal muscle focal adhesion kinase, paxillin, and serum response factor are loading dependent

NASA Technical Reports Server (NTRS)

Gordon, S. E.; Fluck, M.; Booth, F. W.

2001-01-01

This investigation examined the effect of mechanical loading state on focal adhesion kinase (FAK), paxillin, and serum response factor (SRF) in rat skeletal muscle. We found that FAK concentration and tyrosine phosphorylation, paxillin concentration, and SRF concentration are all lower in the lesser load-bearing fast-twitch plantaris and gastrocnemius muscles compared with the greater load-bearing slow-twitch soleus muscle. Of these three muscles, 7 days of mechanical unloading via tail suspension elicited a decrease in FAK tyrosine phosphorylation only in the soleus muscle and decreases in FAK and paxillin concentrations only in the plantaris and gastrocnemius muscles. Unloading decreased SRF concentration in all three muscles. Mechanical overloading (via bilateral gastrocnemius ablation) for 1 or 8 days increased FAK and paxillin concentrations in the soleus and plantaris muscles. Additionally, whereas FAK tyrosine phosphorylation and SRF concentration were increased by < or =1 day of overloading in the soleus muscle, these increases did not occur until somewhere between 1 and 8 days of overloading in the plantaris muscle. These data indicate that, in the skeletal muscles of rats, the focal adhesion complex proteins FAK and paxillin and the transcription factor SRF are generally modulated in association with the mechanical loading state of the muscle. However, the somewhat different patterns of adaptation of these proteins to altered loading in slow- vs. fast-twitch skeletal muscles indicate that the mechanisms and time course of adaptation may partly depend on the prior loading state of the muscle.

Is Hand Selection Modulated by Cognitive-perceptual Load?

PubMed

Liang, Jiali; Wilkinson, Krista; Sainburg, Robert L

2018-01-15

Previous studies proposed that selecting which hand to use for a reaching task appears to be modulated by a factor described as "task difficulty". However, what features of a task might contribute to greater or lesser "difficulty" in the context of hand selection decisions has yet to be determined. There has been evidence that biomechanical and kinematic factors such as movement smoothness and work can predict patterns of selection across the workspace, suggesting a role of predictive cost analysis in hand-selection. We hypothesize that this type of prediction for hand-selection should recruit substantial cognitive resources and thus should be influenced by cognitive-perceptual loading. We test this hypothesis by assessing the role of cognitive-perceptual loading on hand selection decisions, using a visual search task that presents different levels of difficulty (cognitive-perceptual load), as established in previous studies on overall response time and efficiency of visual search. Although the data are necessarily preliminary due to small sample size, our data suggested an influence of cognitive-perceptual load on hand selection, such that the dominant hand was selected more frequently as cognitive load increased. Interestingly, cognitive-perceptual loading also increased cross-midline reaches with both hands. Because crossing midline is more costly in terms of kinematic and kinetic factors, our findings suggest that cognitive processes are normally engaged to avoid costly actions, and that the choice not-to-cross midline requires cognitive resources. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Articular cartilage and subchondral bone in the pathogenesis of osteoarthritis.

PubMed

Goldring, Mary B; Goldring, Steven R

2010-03-01

The articular surface plays an essential role in load transfer across the joint, and conditions that produce increased load transfer or altered patterns of load distribution accelerate the development of osteoarthritis (OA). Current knowledge segregates the risk factors into two fundamental mechanisms related to the adverse effects of "abnormal" loading on normal cartilage or "normal" loading on abnormal cartilage. Although chondrocytes can modulate their functional state in response to loading, their capacity to repair and modify the surrounding extracellular matrix is limited in comparison to skeletal cells in bone. This differential adaptive capacity underlies the more rapid appearance of detectable skeletal changes, especially after acute injuries that alter joint mechanics. The imbalance in the adaptation of the cartilage and bone disrupts the physiological relationship between these tissues and further contributes to OA pathology. This review focuses on the specific articular cartilage and skeletal features of OA and the putative mechanisms involved in their pathogenesis.

Short-term changes in running mechanics and foot strike pattern after introduction to minimalistic footwear.

PubMed

Willson, John D; Bjorhus, Jordan S; Williams, D S Blaise; Butler, Robert J; Porcari, John P; Kernozek, Thomas W

2014-01-01

Minimalistic footwear has garnered widespread interest in the running community, based largely on the premise that the footwear may reduce certain running-related injury risk factors through adaptations in running mechanics and foot strike pattern. To examine short-term adaptations in running mechanics among runners who typically run in conventional cushioned heel running shoes as they transition to minimalistic footwear. A 2-week, prospective, observational study. A movement science laboratory. Nineteen female runners with a rear foot strike (RFS) pattern who usually train in conventional running shoes. The participants trained for 20 minutes, 3 times per week for 2 weeks by using minimalistic footwear. Three-dimensional lower extremity running mechanics were analyzed before and after this 2-week period. Hip, knee, and ankle joint kinematics at initial contact; step length; stance time; peak ankle joint moment and joint work; impact peak; vertical ground reaction force loading rate; and foot strike pattern preference were evaluated before and after the intervention. The knee flexion angle at initial contact increased 3.8° (P < .01), but the ankle and hip flexion angles at initial contact did not change after training. No changes in ankle joint kinetics or running temporospatial parameters were observed. The majority of participants (71%), before the intervention, demonstrated an RFS pattern while running in minimalistic footwear. The proportion of runners with an RFS pattern did not decrease after 2 weeks (P = .25). Those runners who chose an RFS pattern in minimalistic shoes experienced a vertical loading rate that was 3 times greater than those who chose to run with a non-RFS pattern. Few systematic changes in running mechanics were observed among participants after 2 weeks of training in minimalistic footwear. The majority of the participants continued to use an RFS pattern after training in minimalistic footwear, and these participants experienced higher vertical loading rates. Continued exposure to these greater loading rates may have detrimental effects over time. Copyright © 2014 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Reducing Sun Exposure for Prevention of Skin Cancers: Factorial Invariance and Reliability of the Self-Efficacy Scale for Sun Protection

PubMed Central

Babbin, Steven F.; Yin, Hui-Qing; Rossi, Joseph S.; Redding, Colleen A.; Paiva, Andrea L.; Velicer, Wayne F.

2015-01-01

The Self-Efficacy Scale for Sun Protection consists of two correlated factors with three items each for Sunscreen Use and Avoidance. This study evaluated two crucial psychometric assumptions, factorial invariance and scale reliability, with a sample of adults (N = 1356) participating in a computer-tailored, population-based intervention study. A measure has factorial invariance when the model is the same across subgroups. Three levels of invariance were tested, from least to most restrictive: (1) Configural Invariance (nonzero factor loadings unconstrained); (2) Pattern Identity Invariance (equal factor loadings); and (3) Strong Factorial Invariance (equal factor loadings and measurement errors). Strong Factorial Invariance was a good fit for the model across seven grouping variables: age, education, ethnicity, gender, race, skin tone, and Stage of Change for Sun Protection. Internal consistency coefficient Alpha and factor rho scale reliability, respectively, were .84 and .86 for Sunscreen Use, .68 and .70 for Avoidance, and .78 and .78 for the global (total) scale. The psychometric evidence demonstrates strong empirical support that the scale is consistent, has internal validity, and can be used to assess population-based adult samples. PMID:26457203

Relative significance of heat transfer processes to quantify tradeoffs between complexity and accuracy of energy simulations with a building energy use patterns classification

NASA Astrophysics Data System (ADS)

Heidarinejad, Mohammad

This dissertation develops rapid and accurate building energy simulations based on a building classification that identifies and focuses modeling efforts on most significant heat transfer processes. The building classification identifies energy use patterns and their contributing parameters for a portfolio of buildings. The dissertation hypothesis is "Building classification can provide minimal required inputs for rapid and accurate energy simulations for a large number of buildings". The critical literature review indicated there is lack of studies to (1) Consider synoptic point of view rather than the case study approach, (2) Analyze influence of different granularities of energy use, (3) Identify key variables based on the heat transfer processes, and (4) Automate the procedure to quantify model complexity with accuracy. Therefore, three dissertation objectives are designed to test out the dissertation hypothesis: (1) Develop different classes of buildings based on their energy use patterns, (2) Develop different building energy simulation approaches for the identified classes of buildings to quantify tradeoffs between model accuracy and complexity, (3) Demonstrate building simulation approaches for case studies. Penn State's and Harvard's campus buildings as well as high performance LEED NC office buildings are test beds for this study to develop different classes of buildings. The campus buildings include detailed chilled water, electricity, and steam data, enabling to classify buildings into externally-load, internally-load, or mixed-load dominated. The energy use of the internally-load buildings is primarily a function of the internal loads and their schedules. Externally-load dominated buildings tend to have an energy use pattern that is a function of building construction materials and outdoor weather conditions. However, most of the commercial medium-sized office buildings have a mixed-load pattern, meaning the HVAC system and operation schedule dictate the indoor condition regardless of the contribution of internal and external loads. To deploy the methodology to another portfolio of buildings, simulated LEED NC office buildings are selected. The advantage of this approach is to isolate energy performance due to inherent building characteristics and location, rather than operational and maintenance factors that can contribute to significant variation in building energy use. A framework for detailed building energy databases with annual energy end-uses is developed to select variables and omit outliers. The results show that the high performance office buildings are internally-load dominated with existence of three different clusters of low-intensity, medium-intensity, and high-intensity energy use pattern for the reviewed office buildings. Low-intensity cluster buildings benefit from small building area, while the medium- and high-intensity clusters have a similar range of floor areas and different energy use intensities. Half of the energy use in the low-intensity buildings is associated with the internal loads, such as lighting and plug loads, indicating that there are opportunities to save energy by using lighting or plug load management systems. A comparison between the frameworks developed for the campus buildings and LEED NC office buildings indicates these two frameworks are complementary to each other. Availability of the information has yielded to two different procedures, suggesting future studies for a portfolio of buildings such as city benchmarking and disclosure ordinance should collect and disclose minimal required inputs suggested by this study with the minimum level of monthly energy consumption granularity. This dissertation developed automated methods using the OpenStudio API (Application Programing Interface) to create energy models based on the building class. ASHRAE Guideline 14 defines well-accepted criteria to measure accuracy of energy simulations; however, there is no well-accepted methodology to quantify the model complexity without the influence of the energy modeler judgment about the model complexity. This study developed a novel method using two weighting factors, including weighting factors based on (1) computational time and (2) easiness of on-site data collection, to measure complexity of the energy models. Therefore, this dissertation enables measurement of both model complexity and accuracy as well as assessment of the inherent tradeoffs between energy simulation model complexity and accuracy. The results of this methodology suggest for most of the internal load contributors such as operation schedules the on-site data collection adds more complexity to the model compared to the computational time. Overall, this study provided specific data on tradeoffs between accuracy and model complexity that points to critical inputs for different building classes, rather than an increase in the volume and detail of model inputs as the current research and consulting practice indicates. (Abstract shortened by UMI.).

Exploring the interaction of physical exercise load and pattern recall performance in female handball players.

PubMed

Schapschröer, M; Baker, J; Schorer, J

2016-06-01

Studies examining experts' superiority within domain-specific structured pattern recall tasks have typically had athletes perform them at rest, which is far different from how they are executed in their sport. The aim of this study was to investigate whether performing these tasks under different physical exercise intensities influenced pattern recall results of experts, advanced and novices. In two experiments, 68 participants (experiment 1: n = 33; experiment 2: n = 35) were tested using a handball-specific pattern recall task both at rest and during physical exercise. Physical exercises of 60 % heart rate reserve (constant workload: experiment 1) and of 86.5-90 % HRmax (handball-specific interval load: experiment 2) were induced. Results of both experiments revealed significant group differences with experts recalling patterns more accurately than novices but no significant within-subject differences for the two conditions and no interaction between both factors. Our findings replicate prior research concerning perceptual-cognitive expertise in structured specific pattern recall tasks. However, the lack of intergroup differences between the two conditions or interactions was surprising, suggesting sport-specific pattern recall skill is robust to changes in exercise stimuli. Future work is needed to further examine the impact of "physiological specificity" on perceptual-cognitive expertise.

Forecasting of hourly load by pattern recognition in a small area power system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dehdashti-Shahrokh, A.

1982-01-01

An intuitive, logical, simple and efficient method of forecasting hourly load in a small area power system is presented. A pattern recognition approach is used in developing the forecasting model. Pattern recognition techniques are powerful tools in the field of artificial intelligence (cybernetics) and simulate the way the human brain operates to make decisions. Pattern recognition is generally used in analysis of processes where the total physical nature behind the process variation is unkown but specific kinds of measurements explain their behavior. In this research basic multivariate analyses, in conjunction with pattern recognition techniques, are used to develop a linearmore » deterministic model to forecast hourly load. This method assumes that load patterns in the same geographical area are direct results of climatological changes (weather sensitive load), and have occurred in the past as a result of similar climatic conditions. The algorithm described in here searches for the best possible pattern from a seasonal library of load and weather data in forecasting hourly load. To accommodate the unpredictability of weather and the resulting load, the basic twenty-four load pattern was divided into eight three-hour intervals. This division was made to make the model adaptive to sudden climatic changes. The proposed method offers flexible lead times of one to twenty-four hours. The results of actual data testing had indicated that this proposed method is computationally efficient, highly adaptive, with acceptable data storage size and accuracy that is comparable to many other existing methods.« less

Factor structure of the Edinburgh Handedness Inventory versus the Fazio Laterality Inventory in a population with established atypical handedness.

PubMed

Fazio, Rachel L; Cantor, James M

2015-01-01

The Edinburgh Handedness Inventory (EHI) has consistently remained the most used handedness inventory despite its limitations. The psychometric properties of handedness inventories, however, are increasingly important due to their use in matching groups for neuroimaging research. This study compared the performance of the EHI and the Fazio Laterality Inventory (FLI) in a population with atypical handedness. Whereas the EHI demonstrated a single-factor loading in this population, the FLI's previously demonstrated single factor dissociated into two factors: fine motor/ballistic movements and expressive/instrumental movements. This dissociation is similar to that seen when tests of cognitive constructs--which tend to load on a single factor in intact populations--dissociate when administered to populations with difficulties in the assessed domain. This pattern of performance lends further support for the use of the FLI to more accurately assess handedness. Future research in other populations with atypical laterality may illuminate additional factors of the FLI.

Hydrolysis and Sulfation Pattern Effects on Release of Bioactive Bone Morphogenetic Protein-2 from Heparin-Based Microparticles.

PubMed

Tellier, Liane E; Miller, Tobias; McDevitt, Todd C; Temenoff, Johnna S

2015-10-28

Glycosaminoglycans (GAGs) such as heparin are promising materials for growth factor delivery due to their ability to efficiently bind positively charged growth factors including bone morphogenetic protein-2 (BMP-2) through their negatively charged sulfate groups. Therefore, the goal of this study was to examine BMP-2 release from heparin-based microparticles (MPs) after first, incorporating a hydrolytically degradable crosslinker and varying heparin content within MPs to alter MP degradation and second, altering the sulfation pattern of heparin within MPs to vary BMP-2 binding and release. Using varied MP formulations, it was found that the time course of MP degradation for 1 wt% heparin MPs was ~4 days slower than 10 wt% heparin MPs, indicating that MP degradation was dependent on heparin content. After incubating 100 ng BMP-2 with 0.1 mg MPs, most MP formulations loaded BMP-2 with ~50% efficiency and significantly more BMP-2 release (60% of loaded BMP-2) was observed from more sulfated heparin MPs (MPs with ~100% and 80% of native sulfation). Similarly, BMP-2 bioactivity in more sulfated heparin MP groups was at least four-fold higher than soluble BMP-2 and less sulfated heparin MP groups, as determined by an established C2C12 cell alkaline phosphatase (ALP) assay. Ultimately, the two most sulfated 10 wt% heparin MP formulations were able to efficiently load and release BMP-2 while enhancing BMP-2 bioactivity, making them promising candidates for future growth factor delivery applications.

Total Energy Concepts as Applied to Universities.

ERIC Educational Resources Information Center

Gudgeon, R.L.

A comprehensive discussion of single fuel source generation of power and heating requirements is presented. Definition and explanation of system concepts includes--(1) heat pumps, (2) steam turbines, (3) gas turbines, and (4) gas and diesel engines. Concept cost evaluation factors described are--(1) load pattern, (2) campus configuration, (3) fuel…

The influence of climate, nutrient loading and predation on spatial and temporal changes in fish assemblages in Narragansett Bay

EPA Science Inventory

Estuarine fish are a highly valued resources that are affected by several factors, including climate, trophic interactions, pollution, and fishing pressure. Here, we examine the spatial and temporal patterns in estuarine fish assemblage in Narragansett Bay, an estuary located in...

Internal consistency and validity of a new physical workload questionnaire

PubMed Central

Bot, S; Terwee, C; van der Windt, D A W M; Feleus, A; Bierma-Zeinstra, S; Knol, D; Bouter, L; Dekker, J

2004-01-01

Aims: To examine the dimensionality, internal consistency, and construct validity of a new physical workload questionnaire in employees with musculoskeletal complaints. Methods: Factor analysis was applied to the responses in three study populations with musculoskeletal disorders (n = 406, 300, and 557) on 26 items related to physical workload. The internal consistency of the resulting subscales was examined. It was hypothesised that physical workload would vary among different occupational groups. The occupations of all subjects were classified into four groups on the basis of expected workload (heavy physical load; long lasting postures and repetitive movements; both; no physical load). Construct validity of the subscales created was tested by comparing the subscale scores among these occupational groups. Results: The pattern of the factor loadings of items was almost identical for the three study populations. Two interpretable factors were found: items related to heavy physical workload loaded highly on the first factor, and items related to static postures or repetitive work loaded highly on the second factor. The first constructed subscale "heavy physical work" had a Cronbach's α of 0.92 to 0.93 and the second subscale "long lasting postures and repetitive movements", of 0.86 to 0.87. Six of eight hypotheses regarding the construct validity of the subscales were confirmed. Conclusions: The results support the internal structure, internal consistency, and validity of the new physical workload questionnaire. Testing this questionnaire in non-symptomatic employees and comparing its performance with objective assessments of physical workload are important next steps in the validation process. PMID:15550603

Are external knee load and EMG measures accurate indicators of internal knee contact forces during gait?

PubMed

Meyer, Andrew J; D'Lima, Darryl D; Besier, Thor F; Lloyd, David G; Colwell, Clifford W; Fregly, Benjamin J

2013-06-01

Mechanical loading is believed to be a critical factor in the development and treatment of knee osteoarthritis. However, the contact forces to which the knee articular surfaces are subjected during daily activities cannot be measured clinically. Thus, the ability to predict internal knee contact forces accurately using external measures (i.e., external knee loads and muscle electromyographic [EMG] signals) would be clinically valuable. We quantified how well external knee load and EMG measures predict internal knee contact forces during gait. A single subject with a force-measuring tibial prosthesis and post-operative valgus alignment performed four gait patterns (normal, medial thrust, walking pole, and trunk sway) to induce a wide range of external and internal knee joint loads. Linear regression analyses were performed to assess how much of the variability in internal contact forces was accounted for by variability in the external measures. Though the different gait patterns successfully induced significant changes in the external and internal quantities, changes in external measures were generally weak indicators of changes in total, medial, and lateral contact force. Our results suggest that when total contact force may be changing, caution should be exercised when inferring changes in knee contact forces based on observed changes in external knee load and EMG measures. Advances in musculoskeletal modeling methods may be needed for accurate estimation of in vivo knee contact forces. Copyright © 2012 Orthopaedic Research Society.

Consistency and Generalizability of Dietary Patterns in a Multiethnic Working Population.

PubMed

Eng, Jui-Yee; Moy, Foong-Ming; Bulgiba, Awang; Rampal, Sanjay

2018-03-31

Dietary pattern analysis is a complementary method to nutrient analysis in evaluating overall diet-disease hypotheses. Although studies have been conducted to derive dietary patterns among Malaysians, their consistency across subgroups has not been examined. The study aimed to derive dietary patterns empirically and to examine the consistency and generalizability of patterns across sex, ethnicity, and urban status in a working population. This was a cross-sectional study using data from the Clustering of Lifestyle Risk Factors and Understanding its Association with Stress on Health and Well-Being among School Teachers in Malaysia study collected between August 2014 and November 2015. Dietary intake was assessed using a food frequency questionnaire, and dietary patterns were derived using factor analysis. Participants were teachers from selected public schools from three states in Peninsular Malaysia (n=4,618). Dietary patterns derived using factor analysis. Separate factor analysis was conducted by sex, ethnicity, and urban status to identify dietary patterns. Eigenvalue >2, scree plot, Velicer's minimum average partial analysis, and Horn's parallel analysis were used to determine the number of factors to retain. The interpretability of each dietary pattern was evaluated. The consistency and generalizability of dietary patterns across subgroups were assessed using the Tucker congruence coefficient. There was no subgroup-specific dietary pattern found. Thus, dietary patterns were derived using the pooled sample in the final model. Two dietary patterns (Western and Prudent) were derived. The Western dietary pattern explained 15.4% of total variance, characterized by high intakes of refined grains, animal-based foods, added fat, and sugar-sweetened beverages as well as fast food. The Prudent dietary pattern explained 11.1% of total variance and was loaded with pulses, legumes, vegetables, and fruits. The derived Western and Prudent dietary patterns were consistent and generalizable across subgroups of sex, ethnicity, and urban status. Further research is needed to explore associations between these dietary patterns and chronic diseases. Copyright © 2018 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Characterization of craniofacial sutures using the finite element method.

PubMed

Maloul, Asmaa; Fialkov, Jeffrey; Wagner, Diane; Whyne, Cari M

2014-01-03

Characterizing the biomechanical behavior of sutures in the human craniofacial skeleton (CFS) is essential to understand the global impact of these articulations on load transmission, but is challenging due to the complexity of their interdigitated morphology, the multidirectional loading they are exposed to and the lack of well-defined suture material properties. This study aimed to quantify the impact of morphological features, direction of loading and suture material properties on the mechanical behavior of sutures and surrounding bone in the CFS. Thirty-six idealized finite element (FE) models were developed. One additional specimen-specific FE model was developed based on the morphology obtained from a µCT scan to represent the morphological complexity inherent in CFS sutures. Outcome variables of strain energy (SE) and von Mises stress (σvm) were evaluated to characterize the sutures' biomechanical behavior. Loading direction was found to impact the relationship between SE and interdigitation index and yielded varied patterns of σvm in both the suture and surrounding bone. Adding bone connectivity reduced suture strain energy and altered the σvm distribution. Incorporating transversely isotropic material properties was found to reduce SE, but had little impact on stress patterns. High-resolution µCT scanning of the suture revealed a complex morphology with areas of high and low interdigitations. The specimen specific suture model results were reflective of SE absorption and σvm distribution patterns consistent with the simplified FE results. Suture mechanical behavior is impacted by morphologic factors (interdigitation and connectivity), which may be optimized for regional loading within the CFS. © 2013 Elsevier Ltd. All rights reserved.

Metric equivalence assessment in cross-cultural research: using an example of the Center for Epidemiological Studies--Depression Scale.

PubMed

Kim, Miyong; Han, Hae-Ra; Phillips, Linda

2003-01-01

Metric equivalence is a quantitative way to assess cross-cultural equivalences of translated instruments by examining the patterns of psychometric properties based on cross-cultural data derived from both versions of the instrument. Metric equivalence checks at item and instrument levels can be used as a valuable tool to refine cross-cultural instruments. Korean and English versions of the Center for Epidemiological Studies-Depression Scale (CES-D) were administered to 154 Korean Americans and 151 Anglo Americans to illustrate approaches to assessing their metric equivalence. Inter-item and item-total correlations, Cronbach's alpha coefficients, and factor analysis were used for metric equivalence checks. The alpha coefficient for the Korean-American sample was 0.85 and 0.92 for the Anglo American sample. Although all items of the CES-D surpassed the desirable minimum of 0.30 in the Anglo American sample, four items did not meet the standard in the Korean American sample. Differences in average inter-item correlations were also noted between the two groups (0.25 for Korean Americans and 0.37 for Anglo Americans). Factor analysis identified two factors for both groups, and factor loadings showed similar patterns and congruence coefficients. Results of the item analysis procedures suggest the possibility of bias in certain items that may influence the sensitivity of the Korean version of the CES-D. These item biases also provide a possible explanation for the alpha differences. Although factor loadings showed similar patterns for the Korean and English versions of the CES-D, factorial similarity alone is not sufficient for testing the universality of the structure underlying an instrument.

Interpreting the g loadings of intelligence test composite scores in light of Spearman's law of diminishing returns.

PubMed

Reynolds, Matthew R

2013-03-01

The linear loadings of intelligence test composite scores on a general factor (g) have been investigated recently in factor analytic studies. Spearman's law of diminishing returns (SLODR), however, implies that the g loadings of test scores likely decrease in magnitude as g increases, or they are nonlinear. The purpose of this study was to (a) investigate whether the g loadings of composite scores from the Differential Ability Scales (2nd ed.) (DAS-II, C. D. Elliott, 2007a, Differential Ability Scales (2nd ed.). San Antonio, TX: Pearson) were nonlinear and (b) if they were nonlinear, to compare them with linear g loadings to demonstrate how SLODR alters the interpretation of these loadings. Linear and nonlinear confirmatory factor analysis (CFA) models were used to model Nonverbal Reasoning, Verbal Ability, Visual Spatial Ability, Working Memory, and Processing Speed composite scores in four age groups (5-6, 7-8, 9-13, and 14-17) from the DAS-II norming sample. The nonlinear CFA models provided better fit to the data than did the linear models. In support of SLODR, estimates obtained from the nonlinear CFAs indicated that g loadings decreased as g level increased. The nonlinear portion for the nonverbal reasoning loading, however, was not statistically significant across the age groups. Knowledge of general ability level informs composite score interpretation because g is less likely to produce differences, or is measured less, in those scores at higher g levels. One implication is that it may be more important to examine the pattern of specific abilities at higher general ability levels. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Pathophysiology of transfusional iron overload: contrasting patterns in thalassemia major and sickle cell disease.

PubMed

Porter, John B

2009-01-01

The pathophysiological consequences of transfusional iron overload largely reflect the pattern of excess iron distribution and include cardiomyopathy, endocrinopathy, cirrhosis, and hepatocellular carcinoma. Since the introduction of desferrioxamine (DFO) in the late 1970s, these complications have fallen substantially but approximately half of the chelated adult patients with thalassemia major (TM) still show evidence of increased myocardial iron loading by MRI. An understanding of the factors that determine the propensity to extrahepatic iron distribution may be a key to minimizing the pathophysiological consequences of transfusional iron overload. Transfused patients with sickle cell disease (SCD) appear less likely to develop these extrahepatic complications, possibly because plasma nontransferrin-bound iron (NTBI) levels are typically lower than in TM patients at matched levels of iron loading. Other mechanisms that may reduce the extrahepatic iron distribution in SCD include raised plasma hepcidin due to chronic inflammation, lower growth differentiation factor 15 (GDF15) levels because of less ineffective erythropoiesis (IE), and induction of heme oxygenase (HO1) by intravascular hemolysis. Further understanding of these mechanisms may help in designing strategies to decrease extrahepatic iron distribution in TM.

The sludge loading rate regulates the growth and release of heterotrophic bacteria resistant to six types of antibiotics in wastewater activated sludge.

PubMed

Yuan, Qing-Bin; Guo, Mei-Ting; Yang, Jian

2015-01-01

Wastewater treatment plants are considered as hot reservoirs of antimicrobial resistance. However, the fates of antibiotic-resistant bacteria during biological treatment processes and relevant influencing factors have not been fully understood. This study evaluated the effects of the sludge loading rate on the growth and release of six kinds of antibiotic-resistant bacteria in an activated sludge system. The results indicated that higher sludge loading rates amplified the growth of all six types of antibiotic resistant bacteria. The release of most antibiotic-resistant bacteria through both the effluent and biosolids was amplified with increased sludge loading rate. Biosolids were the main pattern for all antibiotic-resistant bacteria release in an activated sludge system, which was determined primarily by their growth in the activated sludge. A higher sludge loading rate reactor tended to retain more antibiotic resistance. An activated sludge system with lower sludge loading rates was considered more conducive to the control of antibiotic resistance.

Off-Loading Practices for the Wounded Foot: Concepts and Choices

PubMed Central

Mrdjenovich, Donald E.

2011-01-01

A wound practitioner’s best-laid plan of care and strategy for healing an ulcerated foot is doomed to fail without a properly conceived approach based on sound off-loading principles. Wound healing that has stalled despite best-practice techniques may require reevaluation of off-loading choices. This is particularly true in the patient with abnormal foot pathologies. Special considerations are certainly required with neuropathic ulcers; however, any wound on a weight-bearing surface of the foot requires proper off-loading. This discussion explores the basic biomechanical and pathomechanical concepts that modify and influence ambulation and gait patterns. Integration of these concepts into the choices for off-loading to deter pathologic influences will alert the reader of precautionary measures and other factors for consideration. The aim of this column is to provide both an adequate working knowledge of the available off-loading devices and the necessary tools and concepts needed to stimulate wise decision protocols for wound management and healing. PMID:24527154

Load pattern and pressure pain threshold in the upper trapezius muscle and psychosocial factors in medical secretaries with and without shoulder/neck disorders.

PubMed

Hägg, G M; Aström, A

1997-01-01

A current hypothesis for the genesis of muscular complaints in the shoulder/neck region postulates that short periods with a completely relaxed muscle are essential to avoid complaints. Another hypothesis is that these disorders are related to psychosocial conditions at work. In order to test these hypotheses, 23 medical secretaries were investigated. The load pattern during work in the upper trapezius muscle bilaterally was assessed with electromyographic (EMG) technique and exposure variation analysis (EVA). In addition, pressure pain threshold (PPT) was measured on the trapezius muscle bilaterally and on the sternum. Psychosocial conditions at work were assessed with a questionnaire. The medical secretaries with complaints had significantly fewer episodes with totally or close to totally relaxed muscle compared with the healthy group. The group with complaints tended to have a more monotonous load pattern at low levels (approx. 1%-5% maximum voluntary contraction) while the healthy group had more frequent pauses but also somewhat more frequent short load peaks. The group with complaints showed lower PPT readings compared with the healthy group. However, the whole group had considerably lower PPTs than is usually reported in the literature. Of the 12 questions in the psychosocial questionnaire only one regarding work task satisfaction showed a significant difference between the two groups. Support is found for hypothesis that secretaries without complaints have more frequent episodes with totally relaxed muscle. A significant difference is found regarding work task satisfaction.

The influence of reservoirs, climate, land use and hydrologic conditions on loads and chemical quality of dissolved organic carbon in the Colorado River

USGS Publications Warehouse

Miller, Matthew P.

2012-01-01

Longitudinal patterns in dissolved organic carbon (DOC) loads and chemical quality were identified in the Colorado River from the headwaters in the Rocky Mountains to the United States-Mexico border from 1994 to 2011. Watershed- and reach-scale climate, land use, river discharge and hydrologic modification conditions that contribute to patterns in DOC were also identified. Principal components analysis (PCA) identified site-specific precipitation and reach-scale discharge as being correlated with sites in the upper basin, where there were increases in DOC load from the upstream to downstream direction. In the lower basin, where DOC load decreased from upstream to downstream, sites were correlated with site-specific temperature and reach-scale population, urban land use and hydrologic modification. In the reaches containing Lakes Powell and Mead, the two largest reservoirs in the United States, DOC quantity decreased, terrestrially derived aromatic DOC was degraded and/or autochthonous less aromatic DOC was produced. Taken together, these results suggest that longitudinal patterns in the relatively unregulated upper basin are influenced by watershed inputs of water and DOC, whereas DOC patterns in the lower basin are reflective of a balance between watershed contribution of water and DOC to the river and loss of water and DOC due to hydrologic modification and/or biogeochemical processes. These findings suggest that alteration of constituent fluxes in rivers that are highly regulated may overshadow watershed processes that would control fluxes in comparable unregulated rivers. Further, these results provide a foundation for detailed assessments of factors controlling the transport and chemical quality of DOC in the Colorado River.

Quantifying traditional Chinese medicine patterns using modern test theory: an example of functional constipation.

PubMed

Shen, Minxue; Cui, Yuanwu; Hu, Ming; Xu, Linyong

2017-01-13

The study aimed to validate a scale to assess the severity of "Yin deficiency, intestine heat" pattern of functional constipation based on the modern test theory. Pooled longitudinal data of 237 patients with "Yin deficiency, intestine heat" pattern of constipation from a prospective cohort study were used to validate the scale. Exploratory factor analysis was used to examine the common factors of items. A multidimensional item response model was used to assess the scale with the presence of multidimensionality. The Cronbach's alpha ranged from 0.79 to 0.89, and the split-half reliability ranged from 0.67 to 0.79 at different measurements. Exploratory factor analysis identified two common factors, and all items had cross factor loadings. Bidimensional model had better goodness of fit than the unidimensional model. Multidimensional item response model showed that the all items had moderate to high discrimination parameters. Parameters indicated that the first latent trait signified intestine heat, while the second trait characterized Yin deficiency. Information function showed that items demonstrated highest discrimination power among patients with moderate to high level of disease severity. Multidimensional item response theory provides a useful and rational approach in validating scales for assessing the severity of patterns in traditional Chinese medicine.

The Corrosion Characteristics and Tensile Behavior of Reinforcement under Coupled Carbonation and Static Loading

PubMed Central

Xu, Yidong

2015-01-01

This paper describes the non-uniform corrosion characteristics and mechanical properties of reinforcement under coupled action of carbonation and static loading. The two parameters, namely area-box (AB) value and arithmetical mean deviation (Ra), are adopted to characterize the corrosion morphology and pitting distribution from experimental observations. The results show that the static loading affects the corrosion characteristics of reinforcement. Local stress concentration in corroded reinforcement caused by tensile stress drives the corrosion pit pattern to be more irregular. The orthogonal test results from finite element simulations show that pit shape and pit depth are the two significant factors affecting the tensile behavior of reinforcement. Under the condition of similar corrosion mass loss ratio, the maximum plastic strain of corroded reinforcement increases with the increase of Ra and load time-history significantly. PMID:28793729

Metal loading levels influence on REE distribution on humic acid: Experimental and Modelling approach

NASA Astrophysics Data System (ADS)

Marsac, R.; Davranche, M.; Gruau, G.; Dia, A.

2009-04-01

In natural organic-rich waters, rare earth elements (REE) speciation is mainly controlled by organic colloids such as humic acid (HA). Different series of REE-HA complexation experiments performed at several metal loading (REE/C) displayed two pattern shapes (i) at high metal loading, a middle-REE (MREE) downward concavity, and (ii) at low metal loading, a regular increase from La to Lu (e.g. Sonke and Salters, 2006; Pourret et al., 2007). Both REE patterns might be related to REE binding with different surface sites on HA. To understand REE-HA binding, REE-HA complexation experiments at various metals loading were carried out using ultrafiltration combined with ICP-MS measurements, for the 14 REE simultaneously. The patterns of the apparent coefficients of REE partition between HA and the inorganic solution (log Kd) evolved regularly according to the metal loading. The REE patterns presented a MREE downward concavity at low loading and a regular increase from La to Lu at high loading. The dataset was modelled with Model VI by adjusting two specific parameters, log KMA, the apparent complexation constant of HA low affinity sites and DLK2, the parameter increasing high affinity sites binding strength. Experiments and modelling provided evidence that HA high affinity sites controlled the REE binding with HA at low metal loading. The REE-HA complex could be as multidentate complexes with carboxylic or phenolic sites or potentially with sites constituted of N, P or S as donor atoms. Moreover, these high affinity sites could be different for light and heavy REE, because heavy REE have higher affinity for these sites, in low density, and could saturate them. These new Model VI parameter sets allowed the prediction of the REE-HA pattern shape evolution on a large range of pH and metal loading. According to the metal loading, the evolution of the calculated REE patterns was similar to the various REE pattern observed in natural acidic organic-rich waters (pH<7 and DOC>10 mg L-1). As a consequence, the metal loading could be the key parameter controlling the REE pattern in organic-rich waters.

Global-scale tectonic patterns on Pluto

NASA Astrophysics Data System (ADS)

Matsuyama, I.; Keane, J. T.; Kamata, S.

2016-12-01

The New Horizons spacecraft revealed a global-scale tectonic pattern on the surface of Pluto which is presumably related to its formation and early evolution. Changes in the rotational and tidal potentials, expansion, and loading can generate stresses capable of producing global-scale tectonic patterns. The current alignment of Sputnik Planum with the tidal axis suggests a reorientation of Pluto relative to the rotation and tidal axes, or true polar wander. This reorientation can be driven by mass loading associated with Sputnik Planum. We developed a general theoretical formalism for the calculation of tectonic patterns due to a variety of process including true polar wander, loading, and expansion. The formalism is general enough to be applicable to non-axisymmetric loads. We illustrate that the observed global-scale tectonic pattern can be explained by stresses generated by true polar wander, Sputnik Planum loading, and expansion.

Mapping the spatial patterns of field traffic and traffic intensity to predict soil compaction risks at the field scale

NASA Astrophysics Data System (ADS)

Duttmann, Rainer; Kuhwald, Michael; Nolde, Michael

2015-04-01

Soil compaction is one of the main threats to cropland soils in present days. In contrast to easily visible phenomena of soil degradation, soil compaction, however, is obscured by other signals such as reduced crop yield, delayed crop growth, and the ponding of water, which makes it difficult to recognize and locate areas impacted by soil compaction directly. Although it is known that trafficking intensity is a key factor for soil compaction, until today only modest work has been concerned with the mapping of the spatially distributed patterns of field traffic and with the visual representation of the loads and pressures applied by farm traffic within single fields. A promising method for for spatial detection and mapping of soil compaction risks of individual fields is to process dGPS data, collected from vehicle-mounted GPS receivers and to compare the soil stress induced by farm machinery to the load bearing capacity derived from given soil map data. The application of position-based machinery data enables the mapping of vehicle movements over time as well as the assessment of trafficking intensity. It also facilitates the calculation of the trafficked area and the modeling of the loads and pressures applied to soil by individual vehicles. This paper focuses on the modeling and mapping of the spatial patterns of traffic intensity in silage maize fields during harvest, considering the spatio-temporal changes in wheel load and ground contact pressure along the loading sections. In addition to scenarios calculated for varying mechanical soil strengths, an example for visualizing the three-dimensional stress propagation inside the soil will be given, using the Visualization Toolkit (VTK) to construct 2D or 3D maps supporting to decision making due to sustainable field traffic management.

Cervicovaginal cytokines, sialidase activity and bacterial load in reproductive-aged women with intermediate vaginal flora.

PubMed

Santos-Greatti, Mariana Morena de Vieira; da Silva, Márcia Guimarães; Ferreira, Carolina Sanitá Tafner; Marconi, Camila

2016-11-01

Studies have shown that not only bacterial vaginosis, but also intermediate vaginal flora has deleterious effects for women's reproductive health. However, literature still lacks information about microbiological and immunological aspects of intermediate flora. To characterize intermediate flora regarding levels of Interleukin (IL)-1beta, IL-6, IL-8, tumor necrosis factor-alpha, interleukin 1 receptor antagonist (IL-1ra), IL-10, sialidase; loads of Gardnerella vaginalis, total bacteria and to verify whether it is closer related to normal flora or bacterial vaginosis. This cross-sectional study enrolled 526 non-pregnant reproductive-aged women distributed in 3 groups according to pattern of vaginal flora using Nugent's system in normal, intermediate and bacterial vaginosis. Cervicovaginal levels of cytokines, sialidases, loads of G. vaginalis and total bacteria were assessed by ELISA, conversion of MUAN and quantitative real-time PCR, respectively. A principal component analysis(PCA) using all measured parameters was performed to compare the three different types of flora. Results showed that intermediate flora is associated with increased cervicovaginal IL-1beta in relation to normal flora(P<0.0001). When compared to bacterial vaginosis, intermediate flora has higher IL-8 and IL-10 levels(P<0.01). Sialidases were in significantly lower levels in normal and intermediate flora than bacterial vaginosis(P<0.0001). Loads of G. vaginalis and total bacterial differed among all groups(P<0.0001), being highest in bacterial vaginosis. PCA showed that normal and intermediate flora were closely scattered, while bacterial vaginosis were grouped separately. Although intermediate flora shows some differences in cytokines, sialidases and bacterial loads in relation to normal flora and bacterial vaginosis, when taken together, general microbiological and immunological pattern pattern of intermediate flora resembles the normal flora. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Elastic band prediction equations for combined free-weight and elastic band bench presses and squats.

PubMed

Shoepe, Todd C; Ramirez, David A; Almstedt, Hawley C

2010-01-01

Elastic bands added to traditional free-weight techniques have become a part of suggested training routines in recent years. Because of the variable loading patterns of elastic bands (i.e., greater stretch produces greater resistance), it is necessary to quantify the exact loading patterns of bands to identify the volume and intensity of training. The purpose of this study was to determine the length vs. tension properties of multiple sizes of a set of commonly used elastic bands to quantify the resistance that would be applied to free-weight plus elastic bench presses (BP) and squats (SQ). Five elastic bands of varying thickness were affixed to an overhead support beam. Dumbbells of varying weights were progressively added to the free end while the linear deformation was recorded with each subsequent weight increment. The resistance was plotted as a factor of linear deformation, and best-fit nonlinear logarithmic regression equations were then matched to the data. For both the BP and SQ loading conditions and all band thicknesses tested, R values were greater than 0.9623. These data suggest that differences in load exist as a result of the thickness of the elastic band, attachment technique, and type of exercise being performed. Facilities should adopt their own form of loading quantification to match their unique set of circumstances when acquiring, researching, and implementing elastic band and free-weight exercises into the training programs.

Algal Turf Sediments and Sediment Production by Parrotfishes across the Continental Shelf of the Northern Great Barrier Reef

PubMed Central

Goatley, Christopher H. R.; Bellwood, David R.

2017-01-01

Sediments are found in the epilithic algal matrix (EAM) of all coral reefs and play important roles in ecological processes. Although we have some understanding of patterns of EAM sediments across individual reefs, our knowledge of patterns across broader spatial scales is limited. We used an underwater vacuum sampler to quantify patterns in two of the most ecologically relevant factors of EAM sediments across the Great Barrier Reef: total load and grain size distribution. We compare these patterns with rates of sediment production and reworking by parrotfishes to gain insights into the potential contribution of parrotfishes to EAM sediments. Inner-shelf reef EAMs had the highest sediment loads with a mean of 864.1 g m-2, compared to 126.8 g m-2 and 287.4 g m-2 on mid- and outer-shelf reefs, respectively. High sediment loads were expected on inner-shelf reefs due to their proximity to the mainland, however, terrigenous siliceous sediments only accounted for 13–24% of total mass. On inner-shelf reef crests parrotfishes would take three months to produce the equivalent mass of sediment found in the EAM. On the outer-shelf it would take just three days, suggesting that inner-shelf EAMs are characterised by low rates of sediment turnover. By contrast, on-reef sediment production by parrotfishes is high on outer-shelf crests. However, exposure to oceanic swells means that much of this production is likely to be lost. Hydrodynamic activity also appears to structure sediment patterns at within-reef scales, with coarser sediments (> 250 μm) typifying exposed reef crest EAMs, and finer sediments (< 250 μm) typifying sheltered back-reef EAMs. As both the load and grain size of EAM sediments mediate a number of important ecological processes on coral reefs, the observed sediment gradients are likely to play a key role in the structure and function of the associated coral reef communities. PMID:28122042

Identification of dietary patterns in urban population of Argentina: study on diet-obesity relation in population-based prevalence study.

PubMed

Pou, Sonia Alejandra; Del Pilar Díaz, María; De La Quintana, Ana Gabriela; Forte, Carla Antonella; Aballay, Laura Rosana

2016-12-01

In Argentina, obesity prevalence rose from 14.6% in 2005 to 20.8% in 2013. Although the number of studies on noncommunicable diseases and dietary patterns as a unique dietary exposure measure has increased, information on this topic remains scarce in developing countries. This is the first population-based study investigating the association between diet and obesity using a dietary pattern approach in Argentina. We aimed (a) to identify current dietary patterns of the population of Córdoba city, (b) to investigate its association with obesity prevalence, and (c) to identify and describe dietary patterns from the subgroup of people with obesity. The Córdoba Obesity and Diet Study (CODIES) was conducted in Córdoba city by using a random sample of n = 4,327 subjects between 2005 and 2012. Empirically derived dietary patterns were identified through principal component factor analysis. A multiple logistic regression analysis was used to investigate the association of dietary patterns with obesity. Four dietary patterns were identified, called " Starchy-Sugar ", " Prudent ", " Western ", and " Sugary drinks ". High scores for the " Western " pattern (with strongest factor loading on meats/eggs, processed meats, and alcohol) showed a positive association with obesity (OR: 1.33, 95% CI: 1.06-1.67, for third versus first tertile of factor score). " Meats/Cheeses " and " Snacks/Alcohol " patterns emerged in people with obesity. The findings suggest that high adherence to the " Western " pattern promoted obesity in this urban population. In addition, people with obesity showed characteristic dietary patterns that differ from those identified in the overall population.

Spatial analysis of instream nitrogen loads and factors controlling nitrogen delivery to streams in the southeastern United States using spatially referenced regression on watershed attributes (SPARROW) and regional classification frameworks

USGS Publications Warehouse

Hoos, A.B.; McMahon, G.

2009-01-01

Understanding how nitrogen transport across the landscape varies with landscape characteristics is important for developing sound nitrogen management policies. We used a spatially referenced regression analysis (SPARROW) to examine landscape characteristics influencing delivery of nitrogen from sources in a watershed to stream channels. Modelled landscape delivery ratio varies widely (by a factor of 4) among watersheds in the southeastern United States - higher in the western part (Tennessee, Alabama, and Mississippi) than in the eastern part, and the average value for the region is lower compared to other parts of the nation. When we model landscape delivery ratio as a continuous function of local-scale landscape characteristics, we estimate a spatial pattern that varies as a function of soil and climate characteristics but exhibits spatial structure in residuals (observed load minus predicted load). The spatial pattern of modelled landscape delivery ratio and the spatial pattern of residuals coincide spatially with Level III ecoregions and also with hydrologic landscape regions. Subsequent incorporation into the model of these frameworks as regional scale variables improves estimation of landscape delivery ratio, evidenced by reduced spatial bias in residuals, and suggests that cross-scale processes affect nitrogen attenuation on the landscape. The model-fitted coefficient values are logically consistent with the hypothesis that broad-scale classifications of hydrologic response help to explain differential rates of nitrogen attenuation, controlling for local-scale landscape characteristics. Negative model coefficients for hydrologic landscape regions where the primary flow path is shallow ground water suggest that a lower fraction of nitrogen mass will be delivered to streams; this relation is reversed for regions where the primary flow path is overland flow.

Spatial analysis of instream nitrogen loads and factors controlling nitrogen delivery to streams in the southeastern United States using spatially referenced regression on watershed attributes (SPARROW) and regional classification frameworks

USGS Publications Warehouse

Hoos, Anne B.; McMahon, Gerard

2009-01-01

Understanding how nitrogen transport across the landscape varies with landscape characteristics is important for developing sound nitrogen management policies. We used a spatially referenced regression analysis (SPARROW) to examine landscape characteristics influencing delivery of nitrogen from sources in a watershed to stream channels. Modelled landscape delivery ratio varies widely (by a factor of 4) among watersheds in the southeastern United States—higher in the western part (Tennessee, Alabama, and Mississippi) than in the eastern part, and the average value for the region is lower compared to other parts of the nation. When we model landscape delivery ratio as a continuous function of local-scale landscape characteristics, we estimate a spatial pattern that varies as a function of soil and climate characteristics but exhibits spatial structure in residuals (observed load minus predicted load). The spatial pattern of modelled landscape delivery ratio and the spatial pattern of residuals coincide spatially with Level III ecoregions and also with hydrologic landscape regions. Subsequent incorporation into the model of these frameworks as regional scale variables improves estimation of landscape delivery ratio, evidenced by reduced spatial bias in residuals, and suggests that cross-scale processes affect nitrogen attenuation on the landscape. The model-fitted coefficient values are logically consistent with the hypothesis that broad-scale classifications of hydrologic response help to explain differential rates of nitrogen attenuation, controlling for local-scale landscape characteristics. Negative model coefficients for hydrologic landscape regions where the primary flow path is shallow ground water suggest that a lower fraction of nitrogen mass will be delivered to streams; this relation is reversed for regions where the primary flow path is overland flow.

Effects of Prosthetic Mismatch and Subscapularis Tear on Glenohumeral Contact Patterns in Total Shoulder Arthroplasty: A Numerical Musculoskeletal Analysis.

PubMed

Sins, Lauranne; Tétreault, Patrice; Nuño, Natalia; Hagemeister, Nicola

2016-12-01

Prosthetic components' mismatch and subscapularis (SC) tear are determining factors for glenoid failure complication in nonconforming total shoulder arthroplasty (NC-TSA). Risk factors are linked to glenoid prosthetic loading. However, the mechanisms underlying the clinical observations remain unclear. This study assessed the combined impact of mismatch and subscapularis tear on glenoid loading. It was assumed that adequate glenoid loading was associated with minimal, but non-null, humeral head translations and contact pressure, as well as with maximal glenoid contact area, and that the center of pressure (COP) on the glenoid would have a centered displacement pattern. A numerical model was used to achieve two objectives. The first was to verify whether an optimum mismatch existed, for which failure risk would be minimal. The second was to explore the effect of subscapularis tear on the position of applied forces on the glenoid. A shoulder AnyBody musculoskeletal model was adapted to the arthroplasty context by introducing humeral head translations and contact between implants. Ten simulations were computed to compare combinations of varying mismatches (1.4 mm, 3.4 mm, 6.4 mm, 8.6 mm, and 9 mm) with two shoulder conditions (intact-muscle or subscapularis tear). Humeral head translations, center-of-pressure, contact area, contact pressure, and glenohumeral joint contact forces were numerically estimated. Mismatches between 3.4 mm and 6.4 mm were associated with the most minimal humeral translations and contact pressure, as well as with maximal contact area. Center of pressure displacement pattern differed according to shoulder condition, with an outward anterior tendency in presence of tear.

Thoracolumbar spine loading associated with kinematics of the young and the elderly during activities of daily living.

PubMed

Ignasiak, Dominika; Rüeger, Andrea; Sperr, Ramona; Ferguson, Stephen J

2018-03-21

Excessive mechanical loading of the spine is a critical factor in vertebral fracture initiation. Most vertebral fractures develop spontaneously or due to mild trauma, as physiological loads during activities of daily living might exceed the failure load of osteoporotic vertebra. Spinal loading patterns are affected by vertebral kinematics, which differ between elderly and young individuals. In this study, the effects of age-related changes in spine kinematics on thoracolumbar spinal segmental loading during dynamic activities of daily living were investigated using combined experimental and modeling approach. Forty-four healthy volunteers were recruited into two age groups: young (N = 23, age = 27.1 ± 3.8) and elderly (N = 21, age = 70.1 ± 3.9). The spinal curvature was assessed with a skin-surface device and the kinematics of the spine and lower extremities were recorded during daily living tasks (flexion-extension and stand-sit-stand) with a motion capture system. The obtained data were used as input for a musculoskeletal model with a detailed thoracolumbar spine representation. To isolate the effect of kinematics on predicted loads, other model properties were kept constant. Inverse dynamics simulations were performed in the AnyBody Modeling System to estimate corresponding spinal loads. The maximum compressive loads predicted for the elderly motion patterns were lower than those of the young for L2/L3 and L3/L4 lumbar levels during flexion and for upper thoracic levels during stand-to-sit (T1/T2-T8/T9) and sit-to-stand (T3/T4-T6/T7). However, the maximum loads predicted for the lower thoracic levels (T9/T10-L1/L2), a common site of vertebral fractures, were similar compared to the young. Nevertheless, these loads acting on the vertebrae of reduced bone quality might contribute to a higher fracture risk for the elderly. Copyright © 2017 Elsevier Ltd. All rights reserved.

Impact of Spatial and Verbal Short-Term Memory Load on Auditory Spatial Attention Gradients.

PubMed

Golob, Edward J; Winston, Jenna; Mock, Jeffrey R

2017-01-01

Short-term memory load can impair attentional control, but prior work shows that the extent of the effect ranges from being very general to very specific. One factor for the mixed results may be reliance on point estimates of memory load effects on attention. Here we used auditory attention gradients as an analog measure to map-out the impact of short-term memory load over space. Verbal or spatial information was maintained during an auditory spatial attention task and compared to no-load. Stimuli were presented from five virtual locations in the frontal azimuth plane, and subjects focused on the midline. Reaction times progressively increased for lateral stimuli, indicating an attention gradient. Spatial load further slowed responses at lateral locations, particularly in the left hemispace, but had little effect at midline. Verbal memory load had no (Experiment 1), or a minimal (Experiment 2) influence on reaction times. Spatial and verbal load increased switch costs between memory encoding and attention tasks relative to the no load condition. The findings show that short-term memory influences the distribution of auditory attention over space; and that the specific pattern depends on the type of information in short-term memory.

Impact of Spatial and Verbal Short-Term Memory Load on Auditory Spatial Attention Gradients

PubMed Central

Golob, Edward J.; Winston, Jenna; Mock, Jeffrey R.

2017-01-01

Short-term memory load can impair attentional control, but prior work shows that the extent of the effect ranges from being very general to very specific. One factor for the mixed results may be reliance on point estimates of memory load effects on attention. Here we used auditory attention gradients as an analog measure to map-out the impact of short-term memory load over space. Verbal or spatial information was maintained during an auditory spatial attention task and compared to no-load. Stimuli were presented from five virtual locations in the frontal azimuth plane, and subjects focused on the midline. Reaction times progressively increased for lateral stimuli, indicating an attention gradient. Spatial load further slowed responses at lateral locations, particularly in the left hemispace, but had little effect at midline. Verbal memory load had no (Experiment 1), or a minimal (Experiment 2) influence on reaction times. Spatial and verbal load increased switch costs between memory encoding and attention tasks relative to the no load condition. The findings show that short-term memory influences the distribution of auditory attention over space; and that the specific pattern depends on the type of information in short-term memory. PMID:29218024

Stresses in pin-loaded orthotropic plates using photoelasticity

NASA Technical Reports Server (NTRS)

Hyer, M. W.; Liu, D.

1984-01-01

The stresses in transparent glass-epoxy plates loaded by a steel pin through a hole were determined by photoelasticity. The stresses around the hole edge, across the net section, along the shear out line, and on the centerline below the hole for quasiisotropic, unidirectional, and angle ply plates are outlined. Stresses in an isotropic comparison specimen are also presented. Stress concentration factors for several locations around the plates are tabulated. The experimental apparatus and the experimental technique are discussed. The isochromatic and isoclinic fringe patterns for the four plates are shown. A description of the necessary photoelastic theory is appended.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghosh, A.; Hsiung, S.M.; Chowdhury, A.H.

Long-term stability of emplacement drifts and potential near-field fluid flow resulting from coupled effects are among the concerns for safe disposal of high-level nuclear waste (HLW). A number of factors can induce drift instability or change the near-field flow patterns. Repetitive seismic loads from earthquakes and thermal loads generated by the decay of emplaced waste are two significant factors. One of two key technical uncertainties (KTU) that can potentially pose a high risk of noncompliance with the performance objectives of 10 CFR Part 60 is the prediction of thermal-mechanical (including repetitive seismic load) effects on stability of emplacement drifts andmore » the engineered barrier system. The second KTU of concern is the prediction of thermal-mechanical-hydrological (including repetitive seismic load) effects on the host rock surrounding the engineered barrier system. The Rock Mechanics research project being conducted at the Center for Nuclear Waste Regulatory Analyses (CNWRA) is intended to address certain specific technical issues associated with these two KTUs. This research project has two major components: (i) seismic response of rock joints and a jointed rock mass and (ii) coupled thermal-mechanical-hydrological (TMH) response of a jointed rock mass surrounding the engineered barrier system (EBS). This final report summarizes the research activities concerned with the repetitive seismic load aspect of both these KTUs.« less

Baby Carriage: Infants Walking with Loads

ERIC Educational Resources Information Center

Garciaguirre, Jessie S.; Adolph, Karen E.; Shrout, Patrick E.

2007-01-01

Maintaining balance is a central problem for new walkers. To examine how infants cope with the additional balance control problems induced by load carriage, 14-month-olds were loaded with 15% of their body weight in shoulder-packs. Both symmetrical and asymmetrical loads disrupted alternating gait patterns and caused less mature footfall patterns.…

Application of Classification Methods for Forecasting Mid-Term Power Load Patterns

NASA Astrophysics Data System (ADS)

Piao, Minghao; Lee, Heon Gyu; Park, Jin Hyoung; Ryu, Keun Ho

Currently an automated methodology based on data mining techniques is presented for the prediction of customer load patterns in long duration load profiles. The proposed approach in this paper consists of three stages: (i) data preprocessing: noise or outlier is removed and the continuous attribute-valued features are transformed to discrete values, (ii) cluster analysis: k-means clustering is used to create load pattern classes and the representative load profiles for each class and (iii) classification: we evaluated several supervised learning methods in order to select a suitable prediction method. According to the proposed methodology, power load measured from AMR (automatic meter reading) system, as well as customer indexes, were used as inputs for clustering. The output of clustering was the classification of representative load profiles (or classes). In order to evaluate the result of forecasting load patterns, the several classification methods were applied on a set of high voltage customers of the Korea power system and derived class labels from clustering and other features are used as input to produce classifiers. Lastly, the result of our experiments was presented.

Experimental evaluation of dynamic data allocation strategies in a distributed database with changing workloads

NASA Technical Reports Server (NTRS)

Brunstrom, Anna; Leutenegger, Scott T.; Simha, Rahul

1995-01-01

Traditionally, allocation of data in distributed database management systems has been determined by off-line analysis and optimization. This technique works well for static database access patterns, but is often inadequate for frequently changing workloads. In this paper we address how to dynamically reallocate data for partionable distributed databases with changing access patterns. Rather than complicated and expensive optimization algorithms, a simple heuristic is presented and shown, via an implementation study, to improve system throughput by 30 percent in a local area network based system. Based on artificial wide area network delays, we show that dynamic reallocation can improve system throughput by a factor of two and a half for wide area networks. We also show that individual site load must be taken into consideration when reallocating data, and provide a simple policy that incorporates load in the reallocation decision.

Admittance Survey of Type 1 Coronae on Venus: Implications for Elastic Thickness

NASA Technical Reports Server (NTRS)

Hoogenboom, T.; Smrekar, S. E.; Anderson, F. S.; Houseman, G.

2003-01-01

Coronae are volcano-tectonic features on Venus which range from 60km to 2600km and are defined by their nearly circular patterns of fractures. Type 1 (regular) coronae are classified as having >50% complete fracture annuli. Previous work has examined the factors controlling the morphology, size, and fracture pattern of coronae, using lithospheric properties, loading signature and geologic characteristics. However, these studies have been limited to Type 2 (topographic) coronae (e.g. coronaes with <50% fracture annuli), and the factors controlling the formation of Type 1 coronae remain poorly understood. In this study, we apply the methodology of to survey the admittance signature for Type 1 coronae to determine the controlling parameters which govern Type 1 coronae formation.

Changes in speckle patterns induced by load application onto an optical fiber and its possible application for sensing purpose

NASA Astrophysics Data System (ADS)

Hasegawa, Makoto; Okumura, Jyun-ya; Hyuga, Akio

2015-08-01

Speckle patterns to be observed in an output light spot from an optical fiber are known to be changed due to external disturbances applied onto the optical fiber. In order to investigate possibilities of utilizing such changes in speckle patterns for sensing application, a certain load was applied onto a jacket-covered communication-grade multi-mode glass optical fiber through which laser beams emitted from a laser diode were propagating, and observed changes in speckle patterns in the output light spot from the optical fiber were investigated both as image data via a CCD camera and as an output voltage from a photovoltaic panel irradiated with the output light spot. The load was applied via a load application mechanism in which several ridges were provided onto opposite flat plates and a certain number of weights were placed there so that corrugated bending of the optical fiber was intentionally induced via load application due to the ridges. The obtained results showed that the number of speckles in the observed pattern in the output light spot as well as the output voltage from the photovoltaic panel irradiated with the output light spot showed decreases upon load application with relatively satisfactory repeatability. When the load was reduced, i.e., the weights were removed, the number of speckles then showed recovery. These results indicate there is a certain possibility of utilizing changes in speckle patterns for sensing of load application onto the optical fiber.

Neighborhood Immigrant Acculturation and Diet among Hispanic Female Residents of NYC

PubMed Central

Park, Yoosun; Neckerman, Kathryn; Quinn, James; Weiss, Christopher; Jacobson, Judith; Rundle, Andrew

2013-01-01

Objective To identify predominant dietary patterns among Hispanic women and to determine whether adherence to dietary patterns is predicted by neighborhood level factors: linguistic isolation, poverty rate and the retail food environment. Design Cross-sectional analyses of predictors of adherence to dietary patterns identified from principle component analyses of data collected using the Study of Women’s Health Across the Nation (SWAN) food frequency questionnaire. Census data were used to measure poverty rates and the percent of Spanish speaking families in the neighborhood in which no one ≥ 14 years old spoke English very well (linguistic isolation) and the retail food environment was measured using business listings data. Setting New York City. Subjects 345 Hispanic women. Results Two major dietary patterns were identified: a healthy diet pattern loading high for vegetable, legumes, potato, fish, and other seafood which explained 17% of the variance in the FFQ data and an energy dense diet pattern loading high for red meat, poultry, pizza, french fries, and high energy drink, which explained 9% of the variance in the FFQ data. Adherence to the healthy diet pattern was positively associated with neighborhood linguistic isolation and negatively associated with neighborhood poverty. More fast food restaurants per Km2 in the neighborhood was significantly associated with lower adherence to the healthy diet. Adherence to the energy dense diet pattern was inversely, but not significantly, associated with neighborhood linguistic isolation. Conclusions These results are consistent with the hypothesis that living in immigrant enclaves is associated with healthy diet patterns among Hispanics. PMID:21414245

Hip ontogenesis: how evolution, genes, and load history shape hip morphotype and cartilotype.

PubMed

Hogervorst, Tom; Eilander, Wouter; Fikkers, Joost T; Meulenbelt, Ingrid

2012-12-01

Developmental hip disorders (DHDs), eg, developmental dysplasia of the hip, slipped capitis femoris epiphysis, and femoroacetabular impingement, can be considered morphology variants of the normal hip. The femoroacetabular morphology of DHD is believed to induce osteoarthritis (OA) through local cumulative mechanical overload acting on genetically controlled patterning systems and subsequent damage of joint structures. However, it is unclear why hip morphology differs between individuals with seemingly comparable load histories and why certain hips with DHD progress to symptomatic OA whereas others do not. We asked (1) which mechanical factors influence growth and development of the proximal femur; and (2) which genes or genetic mechanisms are associated with hip ontogenesis. We performed a systematic literature review of mechanical and genetic factors of hip ontogeny. We focused on three fields that in recent years have advanced our knowledge of adult hip morphology: imaging, evolution, and genetics. WHERE ARE WE NOW?: Mechanical factors can be understood in view of human evolutionary peculiarities and may summate to load histories conducive to DHD. Genetic factors most likely act through multiple genes, each with modest effect sizes. Single genes that explain a DHD are therefore unlikely to be found. Apparently, the interplay between genes and load history not only determines hip morphotype, but also joint cartilage robustness ("cartilotype") and resistance to symptomatic OA. WHERE DO WE NEED TO GO?: We need therapies that can improve both morphotype and cartilotype. HOW DO WE GET THERE?: Better phenotyping, improving classification systems of hip morphology, and comparative population studies can be done with existing methods. Quantifying load histories likely requires new tools, but proof of principle of modifying morphotype in treatment of DDH and of cartilotype with exercise is available.

Psychometric assessment of the processes of change scale for sun protection.

PubMed

Sillice, Marie A; Babbin, Steven F; Redding, Colleen A; Rossi, Joseph S; Paiva, Andrea L; Velicer, Wayne F

2018-01-01

The fourteen-factor Processes of Change Scale for Sun Protection assesses behavioral and experiential strategies that underlie the process of sun protection acquisition and maintenance. Variations of this measure have been used effectively in several randomized sun protection trials, both for evaluation and as a basis for intervention. However, there are no published studies, to date, that evaluate the psychometric properties of the scale. The present study evaluated factorial invariance and scale reliability in a national sample (N = 1360) of adults involved in a Transtheoretical model tailored intervention for exercise and sun protection, at baseline. Invariance testing ranged from least to most restrictive: Configural Invariance (constraints only factor structure and zero loadings); Pattern Identity Invariance (equal factor loadings across target groups); and Strong Factorial Invariance (equal factor loadings and measurement errors). Multi-sample structural equation modeling tested the invariance of the measurement model across seven subgroups: age, education, ethnicity, gender, race, skin tone, and Stage of Change for Sun Protection. Strong factorial invariance was found across all subgroups. Internal consistency coefficient Alpha and factor rho reliability, respectively, were .83 and .80 for behavioral processes, .91 and .89 for experiential processes, and .93 and .91 for the global scale. These results provide strong empirical evidence that the scale is consistent, has internal validity and can be used in research interventions with population-based adult samples.

Cumulative Socioeconomic Status Risk, Allostatic Load, and Adjustment: A Prospective Latent Profile Analysis with Contextual and Genetic Protective Factors

ERIC Educational Resources Information Center

Brody, Gene H.; Yu, Tianyi; Chen, Yi-Fu; Kogan, Steven M.; Evans, Gary W.; Beach, Steven R. H.; Windle, Michael; Simons, Ronald L.; Gerrard, Meg; Gibbons, Frederick X.; Philibert, Robert A.

2013-01-01

The health disparities literature has identified a common pattern among middle-aged African Americans that includes high rates of chronic disease along with low rates of psychiatric disorders despite exposure to high levels of cumulative socioeconomic status (SES) risk. The current study was designed to test hypotheses about the developmental…

Combined Loadings and Cross-Dimensional Loadings Timeliness of Presentation of Financial Statements of Local Government

NASA Astrophysics Data System (ADS)

Muda, I.; Dharsuky, A.; Siregar, H. S.; Sadalia, I.

2017-03-01

This study examines the pattern of readiness dimensional accuracy of financial statements of local government in North Sumatra with a routine pattern of two (2) months after the fiscal year ends and patterns of at least 3 (three) months after the fiscal year ends. This type of research is explanatory survey with quantitative methods. The population and the sample used is of local government officials serving local government financial reports. Combined Analysis And Cross-Loadings Loadings are used with statistical tools WarpPLS. The results showed that there was a pattern that varies above dimensional accuracy of the financial statements of local government in North Sumatra.

Comparing fuel reduction treatments for reducing wildfire size and intensity in a boreal forest landscape of northeastern China.

PubMed

Wu, Zhiwei; He, Hong S; Liu, Zhihua; Liang, Yu

2013-06-01

Fuel load is often used to prioritize stands for fuel reduction treatments. However, wildfire size and intensity are not only related to fuel loads but also to a wide range of other spatially related factors such as topography, weather and human activity. In prioritizing fuel reduction treatments, we propose using burn probability to account for the effects of spatially related factors that can affect wildfire size and intensity. Our burn probability incorporated fuel load, ignition probability, and spread probability (spatial controls to wildfire) at a particular location across a landscape. Our goal was to assess differences in reducing wildfire size and intensity using fuel-load and burn-probability based treatment prioritization approaches. Our study was conducted in a boreal forest in northeastern China. We derived a fuel load map from a stand map and a burn probability map based on historical fire records and potential wildfire spread pattern. The burn probability map was validated using historical records of burned patches. We then simulated 100 ignitions and six fuel reduction treatments to compare fire size and intensity under two approaches of fuel treatment prioritization. We calibrated and validated simulated wildfires against historical wildfire data. Our results showed that fuel reduction treatments based on burn probability were more effective at reducing simulated wildfire size, mean and maximum rate of spread, and mean fire intensity, but less effective at reducing maximum fire intensity across the burned landscape than treatments based on fuel load. Thus, contributions from both fuels and spatially related factors should be considered for each fuel reduction treatment. Published by Elsevier B.V.

The influence of gender-specific loading patterns of the stop-jump task on anterior cruciate ligament strain.

PubMed

Weinhold, Paul S; Stewart, Jason-Dennis N; Liu, Hsin-Yi; Lin, Cheng-Feng; Garrett, William E; Yu, Bing

2007-08-01

Studies have shown that women are at higher risk of sustaining noncontact anterior cruciate ligament (ACL) injuries in specific sports. Recent gait studies of athletic tasks have documented that gender differences in knee movement, muscle activation, and external loading patterns exist. The objective of this study was to determine in a knee cadaver model if application of female-specific loading and movement patterns characterised in vivo for a stop-jump task cause higher ACL strains than male patterns. Gender-specific loading patterns of the landing phase of the vertical stop-jump task were applied to seven cadaver knees using published kinetic/kinematic results for recreational athletes. Loads applied consecutively included: tibial compression, quadriceps, hamstrings, external posterior tibial shear, and tibial torque. Knee flexion was fixed based on the kinematic data. Strain of the ACL was monitored by means of a differential variable reluctance transducer installed on the anterior-medial bundle of the ACL. The ACL strain was significantly increased (P<0.05) for the female loading pattern relative to the male loading pattern after the posterior tibial shear force was applied, and showed a similar trend (P=0.1) to be increased after the final tibial torque was applied. This study suggests that female motor control strategies used during the stop-jump task may place higher strains on the ACL than male strategies, thus putting females at greater risk of ACL injury. We believe these results suggest the potential effectiveness of using training programs to modify motor control strategies and thus modify the risk of injury.

Walking in simulated Martian gravity: influence of the portable life support system's design on dynamic stability.

PubMed

Scott-Pandorf, Melissa M; O'Connor, Daniel P; Layne, Charles S; Josić, Kresimir; Kurz, Max J

2009-09-01

With human exploration of the moon and Mars on the horizon, research considerations for space suit redesign have surfaced. The portable life support system (PLSS) used in conjunction with the space suit during the Apollo missions may have influenced the dynamic balance of the gait pattern. This investigation explored potential issues with the PLSS design that may arise during the Mars exploration. A better understanding of how the location of the PLSS load influences the dynamic stability of the gait pattern may provide insight, such that space missions may have more productive missions with a smaller risk of injury and damaging equipment while falling. We explored the influence the PLSS load position had on the dynamic stability of the walking pattern. While walking, participants wore a device built to simulate possible PLSS load configurations. Floquet and Lyapunov analysis techniques were used to quantify the dynamic stability of the gait pattern. The dynamic stability of the gait pattern was influenced by the position of load. PLSS loads that are placed high and forward on the torso resulted in less dynamically stable walking patterns than loads placed evenly and low on the torso. Furthermore, the kinematic results demonstrated that all joints of the lower extremity may be important for adjusting to different load placements and maintaining dynamic stability. Space scientists and engineers may want to consider PLSS designs that distribute loads evenly and low, and space suit designs that will not limit the sagittal plane range of motion at the lower extremity joints.

Impact of Uncertainty from Load-Based Reserves and Renewables on Dispatch Costs and Emissions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Bowen; Maroukis, Spencer D.; Lin, Yashen

2016-11-21

Aggregations of controllable loads are considered to be a fast-responding, cost-efficient, and environmental-friendly candidate for power system ancillary services. Unlike conventional service providers, the potential capacity from the aggregation is highly affected by factors like ambient conditions and load usage patterns. Previous work modeled aggregations of controllable loads (such as air conditioners) as thermal batteries, which are capable of providing reserves but with uncertain capacity. A stochastic optimal power flow problem was formulated to manage this uncertainty, as well as uncertainty in renewable generation. In this paper, we explore how the types and levels of uncertainty, generation reserve costs, andmore » controllable load capacity affect the dispatch solution, operational costs, and CO2 emissions. We also compare the results of two methods for solving the stochastic optimization problem, namely the probabilistically robust method and analytical reformulation assuming Gaussian distributions. Case studies are conducted on a modified IEEE 9-bus system with renewables, controllable loads, and congestion. We find that different types and levels of uncertainty have significant impacts on dispatch and emissions. More controllable loads and less conservative solution methodologies lead to lower costs and emissions.« less

Study on loading coefficient in steam explosion process of corn stalk.

PubMed

Sui, Wenjie; Chen, Hongzhang

2015-03-01

The object of this work was to evaluate the effect of loading coefficient on steam explosion process and efficacy of corn stalk. Loading coefficient's relation with loading pattern and material property was first revealed, then its effect on transfer process and pretreatment efficacy of steam explosion was assessed by established models and enzymatic hydrolysis tests, respectively, in order to propose its optimization strategy for improving the process economy. Results showed that loading coefficient was mainly determined by loading pattern, moisture content and chip size. Both compact loading pattern and low moisture content improved the energy efficiency of steam explosion pretreatment and overall sugar yield of pretreated materials, indicating that they are desirable to improve the process economy. Pretreatment of small chip size showed opposite effects in pretreatment energy efficiency and enzymatic hydrolysis performance, thus its optimization should be balanced in investigated aspects according to further techno-economical evaluation. Copyright © 2014 Elsevier Ltd. All rights reserved.

The influence of lumbar extensor muscle fatigue on lumbar-pelvic coordination during weightlifting.

PubMed

Hu, Boyi; Ning, Xiaopeng

2015-01-01

Lumbar muscle fatigue is a potential risk factor for the development of low back pain. In this study, we investigated the influence of lumbar extensor muscle fatigue on lumbar-pelvic coordination patterns during weightlifting. Each of the 15 male subjects performed five repetitions of weightlifting tasks both before and after a lumbar extensor muscle fatiguing protocol. Lumbar muscle electromyography was collected to assess fatigue. Trunk kinematics was recorded to calculate lumbar-pelvic continuous relative phase (CRP) and CRP variability. Results showed that fatigue significantly reduced the average lumbar-pelvic CRP value (from 0.33 to 0.29 rad) during weightlifting. The average CRP variability reduced from 0.17 to 0.15 rad, yet this change ws statistically not significant. Further analyses also discovered elevated spinal loading during weightlifting after the development of lumbar extensor muscle fatigue. Our results suggest that frequently experienced lumbar extensor muscle fatigue should be avoided in an occupational environment. Lumbar extensor muscle fatigue generates more in-phase lumbar-pelvic coordination patterns and elevated spinal loading during lifting. Such increase in spinal loading may indicate higher risk of back injury. Our results suggest that frequently experienced lumbar muscle fatigue should be avoided to reduce the risk of LBP.

[Characteristics of nitrogen and phosphorus runoff losses from croplands with different planting patterns in a riverine plain area of Zhejiang Province, East China].

PubMed

Zhang, Ming-Kui; Wang, Yang; Huang, Chao

2011-12-01

By the method of site-specific observation, and selecting 27 field plots with 7 planting patterns in Shaoxing county of Zhejiang Province as test objects, this paper studied the characteristics of nitrogen (N) and phosphorous (P) runoff losses, loads, and their affecting factors in the croplands with different planting patterns in riverine plain area of the Province under natural rainfall. The mean annual runoff loads of total P, dissolved P, and particulate P from the field plots were 4.75, 0.74 and 4.01 kg x hm(-2), respectively, and the load of particulate P was much higher than that of dissolved P. The mean annual runoff loads of total N, dissolved total N, dissolved organic N, NH4(+)-N, and NO3(-)-N were 21.87, 17.19, 0.61, 3.63 and 12.95 kg x hm(-2), respectively, and the load of different fractions of dissolved total N was in the sequence of NO3(-)-N > NH4(+)-N > dissolved organic N. As for the field plots with different planting patterns, the runoff loads of total N, dissolved total N, dissolved organic N, and NO3(-)-N were in the sequence of fallow land < nursery land < single late rice field < double rice field < rape (or wheat)-single late rice field < wheat-early rice-late rice field < vegetable field, while those of total P and particulate P were in the sequence of fallow land < nursery land < single late rice field and double rice field < wheat-early rice-late rice field < rape (wheat)-single late rice field < vegetable field. No significant difference was observed in the load of water-dissolved P among the test plots with different planting patterns. The runoff losses of N and P mainly occurred in crop growth period, and the proportions of N and P losses in the growth period increased with increasing multiple crop index. The runoff losses of total N, dissolved N, and NO3(-)-N were mainly related to the application rate of N fertilizer, and soil NO3(-)-N content also had obvious effects on the runoff losses of total N and dissolved N. The runoff loss of dissolved organic N was related not only to N application rate, but also to soil total N and organic carbon. The runoff loss of NH4(+)-N was mainly related to soil available NH4(+)-N, but not related to N application rate. The runoff losses of total P and particulate P were related to both P application rate and soil available P, while the runoff loss of water dissolved P was less related to P application rate but had relations to soil total P and available P.

PLAN2D - A PROGRAM FOR ELASTO-PLASTIC ANALYSIS OF PLANAR FRAMES

NASA Technical Reports Server (NTRS)

Lawrence, C.

1994-01-01

PLAN2D is a FORTRAN computer program for the plastic analysis of planar rigid frame structures. Given a structure and loading pattern as input, PLAN2D calculates the ultimate load that the structure can sustain before collapse. Element moments and plastic hinge rotations are calculated for the ultimate load. The location of hinges required for a collapse mechanism to form are also determined. The program proceeds in an iterative series of linear elastic analyses. After each iteration the resulting elastic moments in each member are compared to the reserve plastic moment capacity of that member. The member or members that have moments closest to their reserve capacity will determine the minimum load factor and the site where the next hinge is to be inserted. Next, hinges are inserted and the structural stiffness matrix is reformulated. This cycle is repeated until the structure becomes unstable. At this point the ultimate collapse load is calculated by accumulating the minimum load factor from each previous iteration and multiplying them by the original input loads. PLAN2D is based on the program STAN, originally written by Dr. E.L. Wilson at U.C. Berkeley. PLAN2D has several limitations: 1) Although PLAN2D will detect unloading of hinges it does not contain the capability to remove hinges; 2) PLAN2D does not allow the user to input different positive and negative moment capacities and 3) PLAN2D does not consider the interaction between axial and plastic moment capacity. Axial yielding and buckling is ignored as is the reduction in moment capacity due to axial load. PLAN2D is written in FORTRAN and is machine independent. It has been tested on an IBM PC and a DEC MicroVAX. The program was developed in 1988.

Relationship between dietary pattern and cognitive function in elderly patients with type 2 diabetes mellitus.

PubMed

Enomoto, Mari; Yoshii, Hidenori; Mita, Tomoya; Sanke, Haruna; Yokota, Ayako; Yamashiro, Keiko; Inagaki, Noriko; Gosho, Masahiko; Ohmura, Chie; Kudo, Kayo; Watada, Hirotaka; Onuma, Tomio

2015-08-01

To analyse the relationships between dietary patterns and cognitive function in elderly patients with type 2 diabetes mellitus (T2DM). Patients with T2DM completed a 3-day dietary record and Mini-mental State Examination (MMSE). Dietary patterns were identified by factor analysis. The study included 73 patients and identified five dietary patterns, one of which was characterized by high loading for vegetables and fish. A higher consumption of vegetables and fish was significantly associated with improved MMSE score (unadjusted model, model adjusted for age and sex, and model adjusted for age, sex, education, diabetic nephropathy and alcohol consumption), and decreased prevalence of suspected mild dementia (unadjusted model, model adjusted for age and sex). A high score in the vegetables and fish dietary pattern was associated with high MMSE score and low prevalence of suspected mild dementia in elderly patients with T2DM. © The Author(s) 2015.

Horticultural activity predicts later localized limb status in a contemporary pre-industrial population.

PubMed

Stieglitz, Jonathan; Trumble, Benjamin C; Kaplan, Hillard; Gurven, Michael

2017-07-01

Modern humans may have gracile skeletons due to low physical activity levels and mechanical loading. Tests using pre-historic skeletons are limited by the inability to assess behavior directly, while modern industrialized societies possess few socio-ecological features typical of human evolutionary history. Among Tsimane forager-horticulturalists, we test whether greater activity levels and, thus, increased loading earlier in life are associated with greater later-life bone status and diminished age-related bone loss. We used quantitative ultrasonography to assess radial and tibial status among adults aged 20+ years (mean ± SD age = 49 ± 15; 52% female). We conducted systematic behavioral observations to assess earlier-life activity patterns (mean time lag between behavioural observation and ultrasound = 12 years). For a subset of participants, physical activity was again measured later in life, via accelerometry, to determine whether earlier-life time use is associated with later-life activity levels. Anthropometric and demographic data were collected during medical exams. Structural decline with age is reduced for the tibia (female: -0.25 SDs/decade; male: 0.05 SDs/decade) versus radius (female: -0.56 SDs/decade; male: -0.20 SDs/decade), which is expected if greater loading mitigates bone loss. Time allocation to horticulture, but not hunting, positively predicts later-life radial status (β Horticulture  = 0.48, p = 0.01), whereas tibial status is not significantly predicted by subsistence or sedentary leisure participation. Patterns of activity- and age-related change in bone status indicate localized osteogenic responses to loading, and are generally consistent with the logic of bone functional adaptation. Nonmechanical factors related to subsistence lifestyle moderate the association between activity patterns and bone structure. © 2017 Wiley Periodicals, Inc.

Effects of life-history traits on parasitism in a monogamous mammal, the eastern rock sengi ( Elephantulus myurus)

NASA Astrophysics Data System (ADS)

Lutermann, Heike; Medger, Katarina; Horak, Ivan G.

2012-02-01

The distribution of parasites is often characterised by substantial aggregation with a small proportion of hosts harbouring the majority of parasites. This pattern can be generated by abiotic and biotic factors that affect hosts and determine host exposure and susceptibility to parasites. Climate factors can change a host's investment in life-history traits (e.g. growth, reproduction) generating temporal patterns of parasite aggregation. Similarly, host age may affect such investment. Furthermore, sex-biased parasitism is common among vertebrates and has been linked to sexual dimorphism in morphology, behaviour and physiology. Studies exploring sex-biased parasitism have been almost exclusively conducted on polygynous species where dimorphic traits are often correlated. We investigated the effects of season and life-history traits on tick loads of the monogamous eastern rock sengi ( Elephantulus myurus). We found larger tick burdens during the non-breeding season possibly as a result of energetic constraints and/or climate effects on the tick. Reproductive investment resulted in increased larval abundance for females but not males and may be linked to sex-specific life-history strategies. The costs of reproduction could also explain the observed age effect with yearling individuals harbouring lower larval burdens than adults. Although adult males had the greatest larval tick loads, host sex appears to play a minor role in generating the observed parasite heterogeneities. Our study suggests that reproductive investment plays a major role for parasite patterns in the study species.

Distributed patterns of activity in sensory cortex reflect the precision of multiple items maintained in visual short-term memory.

PubMed

Emrich, Stephen M; Riggall, Adam C; Larocque, Joshua J; Postle, Bradley R

2013-04-10

Traditionally, load sensitivity of sustained, elevated activity has been taken as an index of storage for a limited number of items in visual short-term memory (VSTM). Recently, studies have demonstrated that the contents of a single item held in VSTM can be decoded from early visual cortex, despite the fact that these areas do not exhibit elevated, sustained activity. It is unknown, however, whether the patterns of neural activity decoded from sensory cortex change as a function of load, as one would expect from a region storing multiple representations. Here, we use multivoxel pattern analysis to examine the neural representations of VSTM in humans across multiple memory loads. In an important extension of previous findings, our results demonstrate that the contents of VSTM can be decoded from areas that exhibit a transient response to visual stimuli, but not from regions that exhibit elevated, sustained load-sensitive delay-period activity. Moreover, the neural information present in these transiently activated areas decreases significantly with increasing load, indicating load sensitivity of the patterns of activity that support VSTM maintenance. Importantly, the decrease in classification performance as a function of load is correlated with within-subject changes in mnemonic resolution. These findings indicate that distributed patterns of neural activity in putatively sensory visual cortex support the representation and precision of information in VSTM.

Effects of weather and plague-induced die-offs of prairie dogs on the fleas of northern grasshopper mice.

PubMed

Salkeld, Daniel J; Stapp, Paul

2009-05-01

Plague, the disease caused by the bacterium Yersinia pestis, can have devastating impacts on black-tailed prairie dogs (Cynomys ludovicianus Ord). Other mammal hosts living on prairie dog colonies may be important in the transmission and maintenance of plague. We examined the flea populations of northern grasshopper mice (Onychomys leucogaster Wied) before, during, and after plague epizootics in northern Colorado and studied the influence of host and environmental factors on flea abundance patterns. Grasshopper mice were frequently infested with high numbers of fleas, most commonly Pleochaetis exilis Jordan and Thrassis fotus Jordan. Flea loads changed in response to both environmental temperature and rainfall. After plague-induced prairie dog die-offs, flea loads and likelihood of infestation were unchanged for P. exilis, but T. fotus loads declined.

Longitudinal Measurement Invariance of Posttraumatic Stress Disorder in Deployed Marines.

PubMed

Contractor, Ateka A; Bolton, Elisa; Gallagher, Matthew W; Rhodes, Charla; Nash, William P; Litz, Brett

2017-06-01

The meaningful interpretation of longitudinal study findings requires temporal stability of the constructs assessed (i.e., measurement invariance). We sought to examine measurement invariance of the construct of posttraumatic stress disorder (PTSD) as based on the Diagnostic and Statistical Manual of Mental Disorders indexed by the PTSD Checklist (PCL) and the Clinician-Administered PTSD Scale (CAPS) in a sample of 834 Marines with significant combat experience. PTSD was assessed 1-month predeployment (T0), and again at 1-month (T1), 5-months (T2), and 8-months postdeployment (T3). We tested configural (pattern of item/parcel loadings), metric (item/parcel loadings on latent factors), and scalar (item/parcel-level severity) invariance and explored sources of measurement instability (partial invariance testing). The T0 best-fitting emotional numbing model factor structure informed the conceptualization of PTSD's latent factors and parcel formations. We found (1) scalar noninvariance for the construct of PTSD as measured by the PCL and the CAPS, and for PTSD symptom clusters as assessed by the CAPS; and (2) metric noninvariance for PTSD symptom clusters as measured by the PCL. Exploratory analyses revealed factor-loading and intercept differences from pre- to postdeployment for avoidance symptoms, numbing symptoms (mainly psychogenic amnesia and foreshortened future), and the item assessing startle, each of which reduced construct stability. Implications of these findings for longitudinal studies of PTSD are discussed. Copyright © 2017 International Society for Traumatic Stress Studies.

The impact of allostatic load on maternal sympathovagal functioning in stressful child contexts: Implications for problematic parenting

PubMed Central

STURGE-APPLE, MELISSA L.; SKIBO, MICHAEL A.; ROGOSCH, FRED A.; IGNJATOVIC, ZELJKO; HEINZELMAN, WENDI

2011-01-01

The present study applies an allostatic load framework to an examination of the relationship between maternal psychosocial risk factors and maladaptive parenting behaviors. Specifically, the implications of low socioeconomic status and maternal depressive symptoms for maternal sympathovagal functioning during young children’s distress were examined, as well as whether that functioning was, in turn, associated with maternal insensitivity, hostility, intrusiveness, and disengagement during mother–child dyadic interaction. Consistent with an allostatic framework, three patterns of sympathovagal functioning were expected to emerge: normative arousal, hyperarousal, and hypoarousal profiles. Furthermore, meaningful associations between maternal psychosocial risk factors, maladaptive parenting behaviors, and the three profiles of sympathovagal functioning were anticipated. Participants included 153 mother–toddler dyads recruited proportionately from lower and middle socioeconomic status backgrounds. Mothers’ sympathovagal response to their child’s distress was assessed during the Strange Situation paradigm, and mothers’ parenting behavior was assessed during a dyadic free-play interaction. As hypothesized, normative arousal, hyperarousal, and hypoarousal profiles of maternal sympathovagal functioning were identified. Maternal depressive symptomatology predicted the hyperarousal profile, whereas socioeconomic adversity predicted hypoarousal. Moreover, allostatic load profiles were differentially associated with problematic parenting behaviors. These findings underscore the role of physiological dysregulation as a mechanism in the relationship between proximal risk factors and actual maladaptive parenting behaviors. PMID:21756435

Knee Joint Loading during Gait in Healthy Controls and Individuals with Knee Osteoarthritis

PubMed Central

Kumar, Deepak; Manal, Kurt T.; Rudolph, Katherine S.

2013-01-01

Objective People with knee osteoarthritis (OA) are thought to walk with high loads at the knee which are yet to be quantfied using modeling techniques that account for subject specific EMG patterns, kinematics and kinetics. The objective was to estimate medial and lateral loading for people with knee OA and controls using an approach that is sensitive to subject specific muscle activation patterns. Methods 16 OA and 12 control (C) subjects walked while kinematic, kinetic and EMG data were collected. Muscle forces were calculated using an EMG-Driven model and loading was calculated by balancing the external moments with internal muscle and contact forces Results OA subjects walked slower and had greater laxity, static and dynamic varus alignment, less flexion and greater knee adduction moment (KAM). Loading (normalized to body weight) was no different between the groups but OA subjects had greater absolute medial load than controls and maintained a greater %total load on the medial compartment. These patterns were associated with body mass, sagittal and frontal plane moments, static alignment and close to signficance for dynamic alignment. Lateral compartment unloading during mid-late stance was observed in 50% of OA subjects. Conclusions Loading for control subjects was similar to data from instrumented prostheses. Knee OA subjects had high medial contact loads in early stance and half of the OA cohort demonstared lateral compartment lift-off. Results suggest that interventions aimed at reducing body weight and dynamic malalignment might be effective in reducing medial compartment loading and establishing normal medio-lateral load sharing patterns. PMID:23182814

Immediate effects of modified landing pattern on a probabilistic tibial stress fracture model in runners.

PubMed

Chen, T L; An, W W; Chan, Z Y S; Au, I P H; Zhang, Z H; Cheung, R T H

2016-03-01

Tibial stress fracture is a common injury in runners. This condition has been associated with increased impact loading. Since vertical loading rates are related to the landing pattern, many heelstrike runners attempt to modify their footfalls for a lower risk of tibial stress fracture. Such effect of modified landing pattern remains unknown. This study examined the immediate effects of landing pattern modification on the probability of tibial stress fracture. Fourteen experienced heelstrike runners ran on an instrumented treadmill and they were given augmented feedback for landing pattern switch. We measured their running kinematics and kinetics during different landing patterns. Ankle joint contact force and peak tibial strains were estimated using computational models. We used an established mathematical model to determine the effect of landing pattern on stress fracture probability. Heelstrike runners experienced greater impact loading immediately after landing pattern switch (P<0.004). There was an increase in the longitudinal ankle joint contact force when they landed with forefoot (P=0.003). However, there was no significant difference in both peak tibial strains and the risk of tibial stress fracture in runners with different landing patterns (P>0.986). Immediate transitioning of the landing pattern in heelstrike runners may not offer timely protection against tibial stress fracture, despite a reduction of impact loading. Long-term effects of landing pattern switch remains unknown. Copyright © 2016 Elsevier Ltd. All rights reserved.

Autonomous Hybrid Priority Queueing for Scheduling Residential Energy Demands

NASA Astrophysics Data System (ADS)

Kalimullah, I. Q.; Shamroukh, M.; Sahar, N.; Shetty, S.

2017-05-01

The advent of smart grid technologies has opened up opportunities to manage the energy consumption of the users within a residential smart grid system. Demand response management is particularly being employed to reduce the overall load on an electricity network which could in turn reduce outages and electricity costs. The objective of this paper is to develop an intelligible scheduler to optimize the energy available to a micro grid through hybrid queueing algorithm centered around the consumers’ energy demands. This is achieved by shifting certain schedulable load appliances to light load hours. Various factors such as the type of demand, grid load, consumers’ energy usage patterns and preferences are considered while formulating the logical constraints required for the algorithm. The algorithm thus obtained is then implemented in MATLAB workspace to simulate its execution by an Energy Consumption Scheduler (ECS) found within smart meters, which automatically finds the optimal energy consumption schedule tailor made to fit each consumer within the micro grid network.

Loading of PAX3 to Mitotic Chromosomes Is Mediated by Arginine Methylation and Associated with Waardenburg Syndrome*

PubMed Central

Wu, Tsu-Fang; Yao, Ya-Li; Lai, I-Lu; Lai, Chien-Chen; Lin, Pei-Lun; Yang, Wen-Ming

2015-01-01

PAX3 is a transcription factor critical to gene regulation in mammalian development. Mutations in PAX3 are associated with Waardenburg syndrome (WS), but the mechanism of how mutant PAX3 proteins cause WS remains unclear. Here, we found that PAX3 loads on mitotic chromosomes using its homeodomain. PAX3 WS mutants with mutations in homeodomain lose the ability to bind mitotic chromosomes. Moreover, loading of PAX3 on mitotic chromosomes requires arginine methylation, which is regulated by methyltransferase PRMT5 and demethylase JMJD6. Mutant PAX3 proteins that lose mitotic chromosome localization block cell proliferation and normal development of zebrafish. These results reveal the molecular mechanism of PAX3s loading on mitotic chromosomes and the importance of this localization pattern in normal development. Our findings suggest that PAX3 WS mutants interfere with the normal functions of PAX3 in a dominant negative manner, which is important to the understanding of the pathogenesis of Waardenburg syndrome. PMID:26149688

Comparison of nutritional value of „fruit and vegetables” and “western” dietary patterns identified in a group of cancer patients

PubMed

Czekajło, Anna; Różańska, Dorota; Mandecka, Anna; Konikowska, Klaudia; Madalińska, Malwina; Regulska-Ilow, Bożena

Dietary patterns (DPs) are defined as the amounts, types and combinations of various food products in habitual diets and the frequency of their consumption. Dietary pattern analysis is usually performed in order to assess the combined effect of consumed food products on health The aim of the study was to assess and compare the nutritional value of dietary patterns identified in a group of patients staying on the oncological ward The study group consisted of 100 patients (51 women and 49 men) aged 19-83 years. Dietary intake was assessed using a food frequency questionnaire (FFQ) validated for the population of Lower Silesian Voivodeship Factor analysis identified two main dietary patterns explaining 25.6% of variance. The “fruit and vegetables” DP consisted of vegetables, fruits, juices, unrefined grains and nuts, seeds and raisins. Instead, the “Western” DP was characterized by the consumption of high-fat and processed meat and poultry, fried fish, refined grains, honey and sugar, fats, sweets, beverages and chips. While higher scores for “fruit and vegetables” pattern were associated with increased intake of dietary fiber, antioxidant vitamins, folic acid and decreased glycemic load per 1000 kcal and sodium intake, for “Western” pattern observed relationships were opposite. Women were more likely to have higher factor scores for “fruit and vegetables” DP and lower factor scores for “Western” DP than men Dietary patterns identified in the study group differed in terms of nutritional value, in spite of similar macronutrient content in the diet. “Western” DP was characterized by lower nutritional value than “fruit and vegetables” dietary pattern.

Modelling the bathymetry of the Antarctic continental shelf

USGS Publications Warehouse

ten Brink, Uri S.; Rogers, William P.; Kirkham, R.M.

1992-01-01

Continental shelves are typically covered by relatively shallow waters (<200 m) which deepen gradually from the coast to the shelf edge. The continental shelf around Antarctica is deeper than normal (400-700m) and is characterized in many areas by a nearshore trough (up to 1 km deep) that gradually shallows toward the shelf edge. We examine the cause for the unusual shelf bathymetry of Antarctica by 2-D numerical models that simulate the bathymetry along seismic line ODP-119 in Prydz Bay. Line ODP-119 was chosen because it is tied to to 5 ODP boreholes, and because the margin underwent little recent tectonic activity or changes in the glacial drainage pattern. The numerical models incorporate several factors that are likely to influence the bathymetry, such as the load of the ice cap, the isostatic response of the lithosphere, thermal and tectnoic subsidence of the margin, sea level changes, and the patterns of erosion and sedimentation across the margin. The models show that the observed bathymetry can be produced almost entirely by the sum of the outer-shelf sediment loading and inner-shelf unloading and by the load of the slope sediments. A simple statistical mdoel demonstrates that this distribution pattern of erosion and deposition can be generated by multiple cycles of ice sheet advances across the shelf, whereby in each cycle a thin (a few tens of meters) uniform layer of sediments is eroded from under the ice sheet and is redeposited seaward of the grounding line.

Dominance of organic nitrogen from headwater streams to large rivers across the conterminous United States

USGS Publications Warehouse

Scott, D.; Harvey, J.; Alexander, R.; Schwarz, G.

2007-01-01

The frequency and magnitude of hypoxic areas in coastal waterbodies are increasing across the globe, partially in response to the increase in nitrogen delivery from the landscape (Diaz, 2001; Rabalais et al., 2002). Although studies of annual total nitrogen and nitrate yields have greatly improved understanding of the contaminant sources that contribute to riverine nitrogen loads (Alexander et al., 2000; Caraco and Cole, 1999), the emphasis of these studies on annual timescales and selected nitrogen forms is not sufficient to understand the factors that control the cycling, transport, and fate of reactive nitrogen. Here we use data from 850 river stations to calculate long-term mean-annual and interannual loads of organic, ammonia, and nitrate-nitrite nitrogen suitable for spatial analysis. We find that organic nitrogen is the dominant nitrogen pool within rivers across most of the United States and is significant even in basins with high anthropogenic sources of nitrogen. Downstream organic nitrogen patterns illustrate that organic nitrogen is an abundant fraction of the nitrogen loads in all regions. Although the longitudinal patterns are not consistent across regions, these patterns are suggestive of cycling between ON and NO3- on seasonal timescales influenced by land use, stream morphology, and riparian connectivity with active floodplains. Future regional studies need to incorporate multinitrogen species at intraannual timescales, as well as stream characteristics beyond channel depth, to elucidate the roles of nitrogen sources and in-stream transformations on the fate and reactivity of riverine nitrogen transported to coastal seas.

Dominance of organic nitrogen from headwater streams to large rivers across the conterminous United States

NASA Astrophysics Data System (ADS)

Scott, Durelle; Harvey, Judson; Alexander, Richard; Schwarz, Gregory

2007-03-01

The frequency and magnitude of hypoxic areas in coastal waterbodies are increasing across the globe, partially in response to the increase in nitrogen delivery from the landscape (Diaz, 2001; Rabalais et al., 2002). Although studies of annual total nitrogen and nitrate yields have greatly improved understanding of the contaminant sources that contribute to riverine nitrogen loads (Alexander et al., 2000; Caraco and Cole, 1999), the emphasis of these studies on annual timescales and selected nitrogen forms is not sufficient to understand the factors that control the cycling, transport, and fate of reactive nitrogen. Here we use data from 850 river stations to calculate long-term mean-annual and interannual loads of organic, ammonia, and nitrate-nitrite nitrogen suitable for spatial analysis. We find that organic nitrogen is the dominant nitrogen pool within rivers across most of the United States and is significant even in basins with high anthropogenic sources of nitrogen. Downstream organic nitrogen patterns illustrate that organic nitrogen is an abundant fraction of the nitrogen loads in all regions. Although the longitudinal patterns are not consistent across regions, these patterns are suggestive of cycling between ON and NO3- on seasonal timescales influenced by land use, stream morphology, and riparian connectivity with active floodplains. Future regional studies need to incorporate multinitrogen species at intraannual timescales, as well as stream characteristics beyond channel depth, to elucidate the roles of nitrogen sources and in-stream transformations on the fate and reactivity of riverine nitrogen transported to coastal seas.

Joint contact loading in forefoot and rearfoot strike patterns during running.

PubMed

Rooney, Brandon D; Derrick, Timothy R

2013-09-03

Research concerning forefoot strike pattern (FFS) versus rearfoot strike pattern (RFS) running has focused on the ground reaction force even though internal joint contact forces are a more direct measure of the loads responsible for injury. The main purpose of this study was to determine the internal loading of the joints for each strike pattern. A secondary purpose was to determine if converted FFS and RFS runners can adequately represent habitual runners with regards to the internal joint loading. Using inverse dynamics to calculate the net joint moments and reaction forces and optimization techniques to estimate muscle forces, we determined the axial compressive loading at the ankle, knee, and hip. Subjects consisted of 15 habitual FFS and 15 habitual RFS competitive runners. Each subject ran at a preferred running velocity with their habitual strike pattern and then converted to the opposite strike pattern. Plantar flexor muscle forces and net ankle joint moments were greater in the FFS running compared to the RFS running during the first half of the stance phase. The average contact forces during this period increased by 41.7% at the ankle and 14.4% at the knee joint during FFS running. Peak ankle joint contact force was 1.5 body weights greater during FFS running (p<0.05). There was no evidence to support a difference between habitual and converted running for joint contact forces. The increased loading at the ankle joint for FFS is an area of concern for individuals considering altering their foot strike pattern. Copyright © 2013 Elsevier Ltd. All rights reserved.

Finite element analysis of an implant-assisted removable partial denture.

PubMed

Shahmiri, Reza; Aarts, John M; Bennani, Vincent; Atieh, Momen A; Swain, Michael V

2013-10-01

This study analyzes the effects of loading a Kennedy class I implant-assisted removable partial denture (IARPD) using finite element analysis (FEA). Standard RPDs are not originally designed to accommodate a posterior implant load point. The null hypothesis is that the introduction of posteriorly placed implants into an RPD has no effect on the load distribution. A Faro Arm scan was used to extract the geometrical data of a human partially edentulous mandible. A standard plus regular neck (4.8 × 12 mm) Straumann® implant and titanium matrix, tooth roots, and periodontal ligaments were modeled using a combination of reverse engineering in Rapidform XOR2 and solid modeling in Solidworks 2008 FEA program. The model incorporated an RPD and was loaded with a bilateral force of 120 N. ANSYS Workbench 11.0 was used to analyze deformation in the IARPD and elastic strain in the metal framework. FEA identified that the metal framework developed high strain patterns on the major and minor connectors, and the acrylic was subjected to deformation, which could lead to acrylic fractures. The ideal position of the neutral axis was calculated to be 0.75 mm above the ridge. A potentially destructive mismatch of strain distribution was identified between the acrylic and metal framework, which could be a factor in the failure of the acrylic. The metal framework showed high strain patterns on the major and minor connectors around the teeth, while the implant components transferred the load directly to the acrylic. © 2013 by the American College of Prosthodontists.

Principal locations of major-ion, trace-element, nitrate, and Escherichia coli loading to Emigration Creek, Salt Lake County, Utah, October 2005

USGS Publications Warehouse

Kimball, Briant A.; Runkel, Robert L.; Walton-Day, Katherine

2008-01-01

Housing development and recreational activity in Emigration Canyon have increased substantially since 1980, perhaps causing an observed decrease in water quality of this northern Utah stream located near Salt Lake City. To identify reaches of the stream that contribute to water-quality degradation, a tracer-injection and synoptic-sampling study was done to quantify mass loading of major ions, trace elements, nitrate, and Escherichia coli (E. coli) to the stream. The resulting mass-loading profiles for major ions and trace elements indicate both geologic and anthropogenic inputs to the stream, principally from tributary and spring inflows to the stream at Brigham Fork, Burr Fork, Wagner Spring, Emigration Tunnel Spring, Blacksmith Hollow, and Killyon Canyon. The pattern of nitrate loading does not correspond to the major-ion and trace-element loading patterns. Nitrate levels in the stream did not exceed water-quality standards at the time of synoptic sampling. The majority of nitrate mass loading can be considered related to anthropogenic input, based on the field settings and trends in stable isotope ratios of nitrogen. The pattern of E. coli loading does not correspond to the major-ion, trace-element, or nitrate loading patterns. The majority of E. coli loading was related to anthropogenic sources based on field setting, but a considerable part of the loading also comes from possible animal sources in Killyon Canyon, in Perkins Flat, and in Rotary Park. In this late summer sampling, E. coli concentrations only exceeded water-quality standards in limited sections of the study reach. The mass-loading approach used in this study provides a means to design future studies and to evaluate the loading on a catchment scale.

Left ventricular hypertrophy and blood pressure control in automated and continuous ambulatory peritoneal dialysis patients.

PubMed

Ataş, Nuh; Erten, Yasemin; Okyay, Gülay Ulusal; Inal, Salih; Topal, Salih; Öneç, Kürşad; Akyel, Ahmet; Çelik, Bülent; Tavil, Yusuf; Bali, Musa; Arınsoy, Turgay

2014-06-01

Hypertension, non-dipper blood pressure (BP) pattern and decrease in daily urine output have been associated with left ventricular hypertrophy (LVH) in peritoneal dialysis (PD) patients. However, there is lack of data regarding the impact of different PD regimens on these factors. We aimed to investigate the impact of circadian rhythm of BP on LVH in end-stage renal disease patients using automated peritoneal dialysis (APD) or continuous ambulatory peritoneal dialysis (CAPD) modalities. Twenty APD (7 men, 13 women) and 28 CAPD (16 men, 12 women) patients were included into the study. 24-h ambulatory blood pressure monitoring (ABPM) and transthoracic echocardiography besides routine blood examinations were performed. Two groups were compared with each other for ABPM measurements, BP loads, dipping patterns, left ventricular mass index (LVMI) and daily urine output. Mean systolic and diastolic BP measurements, BP loads, LVMI, residual renal function (RRF) and percentage of non-dippers were found to be similar for the two groups. There were positive correlations of LVMI with BP measurements and BP loads. LVMI was found to be significantly higher in diastolic non-dippers compared to dippers (140.4 ± 35.3 vs 114.5 ± 29.7, respectively, P = 0.02). RRF and BP were found to be independent predictors of LVMI. Non-dipping BP pattern was a frequent finding among all PD patients without an inter-group difference. Additionally, higher BP measurements, decrease in daily urine output and non-dipper diastolic BP pattern were associated with LVMI. In order to avoid LVH, besides correction of anemia and volume control, circadian BP variability and diastolic dipping should also be taken into consideration in PD patients. © 2014 The Authors. Therapeutic Apheresis and Dialysis © 2014 International Society for Apheresis.

Specificity of genetic and environmental risk factors for symptoms of cannabis, cocaine, alcohol, caffeine, and nicotine dependence.

PubMed

Kendler, Kenneth S; Myers, John; Prescott, Carol A

2007-11-01

Although genetic risk factors have been found to contribute to dependence on both licit and illicit psychoactive substances, we know little of how these risk factors interrelate. To clarify the structure of genetic and environmental risk factors for symptoms of dependence on cannabis, cocaine, alcohol, caffeine, and nicotine in males and females. Lifetime history by structured clinical interview. General community. Four thousand eight hundred sixty-five members of male-male and female-female pairs from the Virginia Adult Twin Study of Psychiatric and Substance Use Disorders. Main Outcome Measure Lifetime symptoms of abuse of and dependence on cannabis, cocaine, alcohol, caffeine, and nicotine. Controlling for greater symptom prevalence in males, genetic and environmental parameters could be equated across sexes. Two models explained the data well. The best-fit exploratory model contained 2 genetic factors and 1 individual environmental factor contributing to all substances. The first genetic factor loaded strongly on cocaine and cannabis dependence; the second, on alcohol and nicotine dependence. Nicotine and caffeine had high substance-specific genetic effects. A confirmatory model, which also fit well, contained 1 illicit drug genetic factor--loading only on cannabis and cocaine--and 1 licit drug genetic factor loading on alcohol, caffeine, and nicotine. However, these factors were highly intercorrelated (r = + 0.82). Large substance-specific genetic effects remained for nicotine and caffeine. The pattern of genetic and environmental risk factors for psychoactive substance dependence was similar in males and females. Genetic risk factors for dependence on common psychoactive substances cannot be explained by a single factor. Rather, 2 genetic factors-one predisposing largely to illicit drug dependence, the other primarily to licit drug dependence-are needed. Furthermore, a large proportion of the genetic influences on nicotine and particularly caffeine dependence appear to be specific to those substances.

Core networks and their reconfiguration patterns across cognitive loads.

PubMed

Zuo, Nianming; Yang, Zhengyi; Liu, Yong; Li, Jin; Jiang, Tianzi

2018-04-20

Different cognitively demanding tasks recruit globally distributed but functionally specific networks. However, the configuration of core networks and their reconfiguration patterns across cognitive loads remain unclear, as does whether these patterns are indicators for the performance of cognitive tasks. In this study, we analyzed functional magnetic resonance imaging data of a large cohort of 448 subjects, acquired with the brain at resting state and executing N-back working memory (WM) tasks. We discriminated core networks by functional interaction strength and connection flexibility. Results demonstrated that the frontoparietal network (FPN) and default mode network (DMN) were core networks, but each exhibited different patterns across cognitive loads. The FPN and DMN both showed strengthened internal connections at the low demand state (0-back) compared with the resting state (control level); whereas, from the low (0-back) to high demand state (2-back), some connections to the FPN weakened and were rewired to the DMN (whose connections all remained strong). Of note, more intensive reconfiguration of both the whole brain and core networks (but no other networks) across load levels indicated relatively poor cognitive performance. Collectively these findings indicate that the FPN and DMN have distinct roles and reconfiguration patterns across cognitively demanding loads. This study advances our understanding of the core networks and their reconfiguration patterns across cognitive loads and provides a new feature to evaluate and predict cognitive capability (e.g., WM performance) based on brain networks. © 2018 Wiley Periodicals, Inc.

14 CFR 27.337 - Limit maneuvering load factor.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit maneuvering load factor. 27.337... Limit maneuvering load factor. The rotorcraft must be designed for— (a) A limit maneuvering load factor... load factor not less than 2.0 and any negative limit maneuvering load factor of not less than −0.5 for...

14 CFR 29.337 - Limit maneuvering load factor.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit maneuvering load factor. 29.337... Limit maneuvering load factor. The rotorcraft must be designed for— (a) A limit maneuvering load factor... load factor not less than 2.0 and any negative limit maneuvering load factor of not less than −0.5 for...

Comparison of DVH parameters and loading patterns of standard loading, manual and inverse optimization for intracavitary brachytherapy on a subset of tandem/ovoid cases.

PubMed

Jamema, Swamidas V; Kirisits, Christian; Mahantshetty, Umesh; Trnkova, Petra; Deshpande, Deepak D; Shrivastava, Shyam K; Pötter, Richard

2010-12-01

Comparison of inverse planning with the standard clinical plan and with the manually optimized plan based on dose-volume parameters and loading patterns. Twenty-eight patients who underwent MRI based HDR brachytherapy for cervix cancer were selected for this study. Three plans were calculated for each patient: (1) standard loading, (2) manual optimized, and (3) inverse optimized. Dosimetric outcomes from these plans were compared based on dose-volume parameters. The ratio of Total Reference Air Kerma of ovoid to tandem (TRAK(O/T)) was used to compare the loading patterns. The volume of HR CTV ranged from 9-68 cc with a mean of 41(±16.2) cc. Mean V100 for standard, manual optimized and inverse plans was found to be not significant (p=0.35, 0.38, 0.4). Dose to bladder (7.8±1.6 Gy) and sigmoid (5.6±1.4 Gy) was high for standard plans; Manual optimization reduced the dose to bladder (7.1±1.7 Gy p=0.006) and sigmoid (4.5±1.0 Gy p=0.005) without compromising the HR CTV coverage. The inverse plan resulted in a significant reduction to bladder dose (6.5±1.4 Gy, p=0.002). TRAK was found to be 0.49(±0.02), 0.44(±0.04) and 0.40(±0.04) cGy m(-2) for the standard loading, manual optimized and inverse plans, respectively. It was observed that TRAK(O/T) was 0.82(±0.05), 1.7(±1.04) and 1.41(±0.93) for standard loading, manual optimized and inverse plans, respectively, while this ratio was 1 for the traditional loading pattern. Inverse planning offers good sparing of critical structures without compromising the target coverage. The average loading pattern of the whole patient cohort deviates from the standard Fletcher loading pattern. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Three-dimensional analyses of ultrasonic scaler oscillations.

PubMed

Lea, Simon C; Felver, Bernhard; Landini, Gabriel; Walmsley, A Damien

2009-01-01

It is stated that the oscillation patterns of dental ultrasonic scalers are dependent upon whether the instrument is of a magnetostrictive or piezoelectric design. These patterns are then linked to differences in root surface debridement in vitro. Piezoelectric (A, P) and magnetostrictive (Slimline, TFI-3) ultrasonic scalers (three of each) were evaluated, loaded (100 g/200 g) and unloaded with a 3D laser vibrometer. Loads were applied to the probe tips via teeth mounted in a load-measuring device. Elliptical motion was demonstrated for all probes under loaded and unloaded conditions. Loading flattened the elliptical motion along the length of the probe. Unloaded, Slimline tip 1 was significantly different to tips 2 and 3 (p<0.0001). There were no differences between the A-tips (p>0.207). All TFI-3 tips were different to each other (p<0.0001). P-tips 1 and 2 were different to each other (p=0.046). Loaded, Slimline tips were different to each other (p<0.001). There were no differences between the P probes (p>0.867). Generator power increased all Slimline and P tip vibrations (p<0.0001). Probe oscillation patterns are independent of ultrasound production mechanism and are dependent upon probe shape and generator power. Loaded probes oscillated with an elliptical pattern.

Nuclear fuel management optimization using genetic algorithms

DOE Office of Scientific and Technical Information (OSTI.GOV)

DeChaine, M.D.; Feltus, M.A.

1995-07-01

The code independent genetic algorithm reactor optimization (CIGARO) system has been developed to optimize nuclear reactor loading patterns. It uses genetic algorithms (GAs) and a code-independent interface, so any reactor physics code (e.g., CASMO-3/SIMULATE-3) can be used to evaluate the loading patterns. The system is compared to other GA-based loading pattern optimizers. Tests were carried out to maximize the beginning of cycle k{sub eff} for a pressurized water reactor core loading with a penalty function to limit power peaking. The CIGARO system performed well, increasing the k{sub eff} after lowering the peak power. Tests of a prototype parallel evaluation methodmore » showed the potential for a significant speedup.« less

Gait alterations can reduce the risk of edge loading.

PubMed

Wesseling, Mariska; Meyer, Christophe; De Groote, Friedl; Corten, Kristoff; Simon, Jean-Pierre; Desloovere, Kaat; Jonkers, Ilse

2016-06-01

Following metal-on-metal hip arthroplasty, edge loading (i.e., loading near the edge of a prosthesis cup) can increase wear and lead to early revision. The position and coverage angle of the prosthesis cup influence the risk of edge loading. This study investigates the effect of altered gait patterns, more specific hip, and pelvis kinematics, on the orientation of hip contact force and the consequent risk of antero-superior edge loading using muscle driven simulations of gait. With a cup orientation of 25° anteversion and 50° inclination and a coverage angle of 168°, many gait patterns presented risk of edge loading. Specifically at terminal double support, 189 out of 405 gait patterns indicated a risk of edge loading. At this time instant, the high hip contact forces and the proximity of the hip contact force to the edge of the cup indicated the likelihood of the occurrence of edge loading. Although the cup position contributed most to edge loading, altering kinematics considerably influenced the risk of edge loading. Increased hip abduction, resulting in decreasing hip contact force magnitude, and decreased hip extension, resulting in decreased risk on edge loading, are gait strategies that could prevent edge loading. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1069-1076, 2016. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

A systematic review of the evidence supporting a causal link between dietary factors and coronary heart disease.

PubMed

Mente, Andrew; de Koning, Lawrence; Shannon, Harry S; Anand, Sonia S

2009-04-13

Although a wealth of literature links dietary factors and coronary heart disease (CHD), the strength of the evidence supporting valid associations has not been evaluated systematically in a single investigation. We conducted a systematic search of MEDLINE for prospective cohort studies or randomized trials investigating dietary exposures in relation to CHD. We used the Bradford Hill guidelines to derive a causation score based on 4 criteria (strength, consistency, temporality, and coherence) for each dietary exposure in cohort studies and examined for consistency with the findings of randomized trials. Strong evidence supports valid associations (4 criteria satisfied) of protective factors, including intake of vegetables, nuts, and "Mediterranean" and high-quality dietary patterns with CHD, and associations of harmful factors, including intake of trans-fatty acids and foods with a high glycemic index or load. Among studies of higher methodologic quality, there was also strong evidence for monounsaturated fatty acids and "prudent" and "western" dietary patterns. Moderate evidence (3 criteria) of associations exists for intake of fish, marine omega-3 fatty acids, folate, whole grains, dietary vitamins E and C, beta carotene, alcohol, fruit, and fiber. Insufficient evidence (< or =2 criteria) of association is present for intake of supplementary vitamin E and ascorbic acid (vitamin C); saturated and polyunsaturated fatty acids; total fat; alpha-linolenic acid; meat; eggs; and milk. Among the dietary exposures with strong evidence of causation from cohort studies, only a Mediterranean dietary pattern is related to CHD in randomized trials. The evidence supports a valid association of a limited number of dietary factors and dietary patterns with CHD. Future evaluation of dietary patterns, including their nutrient and food components, in cohort studies and randomized trials is recommended.

Bilateral Asymmetry in the Human Pelvis.

PubMed

Kurki, Helen K

2017-04-01

Asymmetry of the human axial skeleton has received much less attention that of the limb skeleton. Pelvic morphology is subject to multiple selective factors, including bipedal locomotion and obstetrics, among others, as well as environmental factors such as biomechanical loading. How these various factors influence or restrict asymmetry of the pelvis is unknown and few studies have investigated levels and patterns of pelvic asymmetry. This study examines percentage directional (%DA) and absolute (%AA) asymmetry in 14 bilaterally paired dimensions of the pelvic canal, non-canal pelvis, and femur in female (n = 111) and male (n = 126) skeletons from nine geographically dispersed skeletal samples. Directional asymmetries were uniformly low for all measures and lacked any consistent patterning across the variables, while %AA was highest in the pelvic canal, particularly the posterior aspects. Few sex differences and no population differences were found for %DA and %AA; however the latter was correlated with coefficients of variation across the 14 variables in both sexes. While sample mean %DA were low, standard deviations of the canal variables were high and the majority of individuals in both sexes displayed %DA values >±0.5, suggesting asymmetry is common, if not directionally consistent. Biomechanical loading of the pelvic girdle may influence asymmetry of both the canal and non-canal aspects of the pelvis; however it is unlikely that these asymmetries negatively affect obstetric function, given the prevalence for %DA found in this study. Anat Rec, 300:653-665, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

The synergistic effects of shear stress and cyclic hydrostatic pressure modulate chondrogenic induction of human mesenchymal stem cells.

PubMed

Hosseini, Motahare-Sadat; Tafazzoli-Shadpour, Mohammad; Haghighipour, Nooshin; Aghdami, Naser; Goodarzi, Alireza

2015-10-01

In this study, we examined chondrogenic regulation of 2 types of mesenchymal stem cells seeded on the bioengineered substrate in monolayer cultures under mechanically defined conditions to mimic the in vivo microenvironment of chondrocytes within articular cartilage tissues. Human adipose-derived mesenchymal stem cells (ASCs) and bone marrow mesenchymal stem cells (BSCs) were exposed to 0.2 Pa shear stress, 3 MPa cyclic hydrostatic pressure, and combined loading with different sequences on chemically designed medical-grade silicone rubber, while no soluble growth factors were added to the culture medium. The expression levels of chondrogenic-specific genes of SOX9, aggrecan, and type II collagen (Col II) were measured. Results were compared to those of cells treated by biological growth factor. Gene expression patterns were dependent on the loading regime. Moreover, the source of mesenchymal stem cells (adipose or bone marrow) was influential in gene expression. Overall, enhanced expression of chondrogenic markers was found through application of mechanical stimuli. The response was generally found to be significantly promoted when the 2 loading regimes were superimposed. Differentiation of ASCs was shown by a modest increase in gene expression profiles. In general, BSCs expressed higher levels of chondrogenic gene expression than ASCs after 3 weeks. A greater effect on Col II and SOX9 mRNA expression was observed when combined loadings were applied. Results may be applied in determining the proper loading sequence for obtaining functional target cells in cartilage engineering applications.

14 CFR 23.337 - Limit maneuvering load factors.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit maneuvering load factors. 23.337... Flight Loads § 23.337 Limit maneuvering load factors. (a) The positive limit maneuvering load factor n... airplanes; or (3) 6.0 for acrobatic category airplanes. (b) The negative limit maneuvering load factor may...

Stress analysis for structures with surface cracks

NASA Technical Reports Server (NTRS)

Bell, J. C.

1978-01-01

Two basic forms of analysis, one treating stresses around arbitrarily loaded circular cracks, the other treating stresses due to loads arbitrarily distributed on the surface of a half space, are united by a boundary-point least squares method to obtain analyses for stresses from surface cracks in places or bars. Calculations were for enough cases to show how effects from the crack vary with the depth-to-length ratio, the fractional penetration ratio, the obliquity of the load, and to some extent the fractional span ratio. The results include plots showing stress intensity factors, stress component distributions near the crack, and crack opening displacement patterns. Favorable comparisons are shown with two kinds of independent experiments, but the main method for confirming the results is by wide checking of overall satisfaction of boundary conditions, so that external confirmation is not essential. Principles involved in designing analyses which promote dependability of the results are proposed and illustrated.

Dietary patterns and changes in body composition in children between 9 and 11 years

PubMed Central

Smith, Andrew D. A. C.; Emmett, Pauline M.; Newby, P. K.; Northstone, Kate

2014-01-01

Objective Childhood obesity is rising and dietary intake is a potentially modifiable factor that plays an important role in its development. We aim to investigate the association between dietary patterns, obtained through principal components analysis and gains in fat and lean mass in childhood. Design Diet diaries at 10 years of age collected from children taking part in the Avon Longitudinal Study of Parents and Children. Body composition was assessed using dual-energy X-ray absorptiometry at 9 and 11. Setting Longitudinal birth cohort. Subjects 3911 children with complete data. Results There was an association between the Health Aware (positive loadings on high-fiber bread, and fruits and vegetables; negative loadings on chips, crisps, processed meat, and soft drinks) pattern score and decreased fat mass gain in girls. After adjusting for confounders, an increase of 1 standard deviation (sd) in this score led to an estimated 1.2% decrease in fat mass gain in valid-reporters and 2.1% in under-reporters. A similar decrease was found only in under-reporting boys. There was also an association between the Packed Lunch (high consumption of white bread, sandwich fillings, and snacks) pattern score and decreased fat mass gain (1.1% per sd) in valid-reporting but not under-reporting girls. The main association with lean mass gain was an increase with Packed Lunch pattern score in valid-reporting boys only. Conclusions There is a small association between dietary patterns and change in fat mass in mid-childhood. Differences between under- and valid-reporters emphasize the need to consider valid-reporters separately in such studies. PMID:25018688

Plantar loading changes with alterations in foot strike patterns during a single session in habitual rear foot strike female runners.

PubMed

Kernozek, Thomas W; Vannatta, Charles N; Gheidi, Naghmeh; Kraus, Sydnie; Aminaka, Naoko

2016-03-01

Characterize plantar loading parameters when habitually rear foot strike (RFS) runners change their pattern to a non-rear foot strike (NRFS). Experimental. University biomechanics laboratory. Twenty three healthy female runners (Age: 22.17 ± 1.64 yrs; Height: 168.91 ± 5.46 cm; Mass: 64.29 ± 7.11 kg). Plantar loading was measured using an in-sole pressure sensor while running down a 20-m runway restricted to a range of 3.52-3.89 m/s under two conditions, using the runner's typical RFS, and an adapted NRFS pattern. Repeated measures multivariate analysis of variance was performed to detect differences in loading between these two conditions. Force and pressure variables were greater in the forefoot and phalanx in NRFS and greater in the heel and mid foot in RFS pattern, but the total force imposed upon the whole foot and contact time remained similar between conditions. Total peak pressure was higher and contact area was lower during NRFS running. The primary finding of this investigation is that there are distinctly different plantar loads when changing from a RFS to NRFS during running. So, during a transition from RFS to a NRFS pattern; a period of acclimation should be considered to allow for adaptations to these novel loads incurred on plantar regions of the foot. Copyright © 2015 Elsevier Ltd. All rights reserved.

Parallel traveling-wave MRI: a feasibility study.

PubMed

Pang, Yong; Vigneron, Daniel B; Zhang, Xiaoliang

2012-04-01

Traveling-wave magnetic resonance imaging utilizes far fields of a single-piece patch antenna in the magnet bore to generate radio frequency fields for imaging large-size samples, such as the human body. In this work, the feasibility of applying the "traveling-wave" technique to parallel imaging is studied using microstrip patch antenna arrays with both the numerical analysis and experimental tests. A specific patch array model is built and each array element is a microstrip patch antenna. Bench tests show that decoupling between two adjacent elements is better than -26-dB while matching of each element reaches -36-dB, demonstrating excellent isolation performance and impedance match capability. The sensitivity patterns are simulated and g-factors are calculated for both unloaded and loaded cases. The results on B 1- sensitivity patterns and g-factors demonstrate the feasibility of the traveling-wave parallel imaging. Simulations also suggest that different array configuration such as patch shape, position and orientation leads to different sensitivity patterns and g-factor maps, which provides a way to manipulate B(1) fields and improve the parallel imaging performance. The proposed method is also validated by using 7T MR imaging experiments. Copyright © 2011 Wiley-Liss, Inc.

Distinct spinning patterns gain differentiated loading tolerance of silk thread anchorages in spiders with different ecology.

PubMed

Wolff, Jonas O; van der Meijden, Arie; Herberstein, Marie E

2017-07-26

Building behaviour in animals extends biological functions beyond bodies. Many studies have emphasized the role of behavioural programmes, physiology and extrinsic factors for the structure and function of buildings. Structure attachments associated with animal constructions offer yet unrealized research opportunities. Spiders build a variety of one- to three-dimensional structures from silk fibres. The evolution of economic web shapes as a key for ecological success in spiders has been related to the emergence of high performance silks and thread coating glues. However, the role of thread anchorages has been widely neglected in those models. Here, we show that orb-web (Araneidae) and hunting spiders (Sparassidae) use different silk application patterns that determine the structure and robustness of the joint in silk thread anchorages. Silk anchorages of orb-web spiders show a greater robustness against different loading situations, whereas the silk anchorages of hunting spiders have their highest pull-off resistance when loaded parallel to the substrate along the direction of dragline spinning. This suggests that the behavioural 'printing' of silk into attachment discs along with spinneret morphology was a prerequisite for the evolution of extended silk use in a three-dimensional space. This highlights the ecological role of attachments in the evolution of animal architectures. © 2017 The Author(s).

Early In Vitro Differentiation of Mouse Definitive Endoderm Is Not Correlated with Progressive Maturation of Nuclear DNA Methylation Patterns

PubMed Central

Tajbakhsh, Jian; Gertych, Arkadiusz; Fagg, W. Samuel; Hatada, Seigo; Fair, Jeffrey H.

2011-01-01

The genome organization in pluripotent cells undergoing the first steps of differentiation is highly relevant to the reprogramming process in differentiation. Considering this fact, chromatin texture patterns that identify cells at the very early stage of lineage commitment could serve as valuable tools in the selection of optimal cell phenotypes for regenerative medicine applications. Here we report on the first-time use of high-resolution three-dimensional fluorescence imaging and comprehensive topological cell-by-cell analyses with a novel image-cytometrical approach towards the identification of in situ global nuclear DNA methylation patterns in early endodermal differentiation of mouse ES cells (up to day 6), and the correlations of these patterns with a set of putative markers for pluripotency and endodermal commitment, and the epithelial and mesenchymal character of cells. Utilizing this in vitro cell system as a model for assessing the relationship between differentiation and nuclear DNA methylation patterns, we found that differentiating cell populations display an increasing number of cells with a gain in DNA methylation load: first within their euchromatin, then extending into heterochromatic areas of the nucleus, which also results in significant changes of methylcytosine/global DNA codistribution patterns. We were also able to co-visualize and quantify the concomitant stochastic marker expression on a per-cell basis, for which we did not measure any correlation to methylcytosine loads or distribution patterns. We observe that the progression of global DNA methylation is not correlated with the standard transcription factors associated with endodermal development. Further studies are needed to determine whether the progression of global methylation could represent a useful signature of cellular differentiation. This concept of tracking epigenetic progression may prove useful in the selection of cell phenotypes for future regenerative medicine applications. PMID:21779341

A method for determination of equine hoof strain patterns using photoelasticity: an in vitro study.

PubMed

Dejardin, L M; Arnoczky, S P; Cloud, G L

1999-05-01

During impact, equine hooves undergo viscoelastic deformations which may result in potentially harmful strains. Previous hoof strain studies using strain gauges have been inconclusive due to arbitrary gauge placement. Photoelastic stress analysis (PSA) is a full-field technique which visually displays strains over entire loaded surfaces. This in vitro study identifies normal hoof strain patterns using PSA. Custom-made photoelastic plastic sheets were applied to the hoof surface. The hooves were axially loaded (225 kg) under level and varus/valgus conditions. Strain patterns were video-recorded through a polariscope. Strains were concentrated between middle and distal thirds of the hoof wall regardless of the loading conditions. This strain distribution appears to result from the differential expansion of the hoof wall under load. Increasing load resulted in higher strains and asymmetric loading resulted in an ipsilateral increase in strain magnitudes without altering strain locations. This study shows that PSA is a reliable method with which to evaluate hoof strains in vitro and is sensitive enough to reflect subtle load-related strain alterations.

Numerical Simulation of the Ground Response to the Tire Load Using Finite Element Method

NASA Astrophysics Data System (ADS)

Valaskova, Veronika; Vlcek, Jozef

2017-10-01

Response of the pavement to the excitation caused by the moving vehicle is one of the actual problems of the civil engineering practice. The load from the vehicle is transferred to the pavement structure through contact area of the tires. Experimental studies show nonuniform distribution of the pressure in the area. This non-uniformity is caused by the flexible nature and the shape of the tire and is influenced by the tire inflation. Several tire load patterns, including uniform distribution and point load, were involved in the numerical modelling using finite element method. Applied tire loads were based on the tire contact forces of the lorry Tatra 815. There were selected two procedures for the calculations. The first one was based on the simplification of the vehicle to the half-part model. The characteristics of the vehicle model were verified by the experiment and by the numerical model in the software ADINA, when vehicle behaviour during the ride was investigated. Second step involved application of the calculated contact forces for the front axle as the load on the multi-layered half space representing the pavement structure. This procedure was realized in the software Plaxis and considered various stress patterns for the load. The response of the ground to the vehicle load was then analyzed. Axisymmetric model was established for this procedure. The paper presents the results of the investigation of the contact pressure distribution and corresponding reaction of the pavement to various load distribution patterns. The results show differences in some calculated quantities for different load patterns, which need to be verified by the experimental way when also ground response should be observed.

Individual patient's preferences for hypertension management: a Q-methodological approach.

PubMed

Morecroft, Charles; Cantrill, Judy; Tully, Mary P

2006-06-01

To systematically explore and elicit individual patient's preferences in the management of their hypertension using Q-methodology. Using Q-methodology, 120 patients ranking 42 statements according to their agreement or disagreement when considering appropriate hypertension management. The statements were derived from an earlier qualitative study. Factor analysis of the data was undertaken using PQMethod software to determine if any patterns were discernible. Ninety-two patients clustered to five factors, which all varied in the degree of involvement patients had, or wished to have, in their hypertension management. The 42 patients who loaded to factor 1 considered that appropriate antihypertensive treatment involved leaving medical decisions to their GPs and trusting their judgement in such matters. The patients (n = 31) who positively loaded to factor 2 suggested that an autonomous relationship with their healthcare professional(s) was an important issue when considering treatment. It is concluded that this study has successfully used Q-methodology to systematically investigate people's subjectivity and developed a novel approach to elicit the views of individual patients, as well as explore and differentiate between groups of patients. The formation of true partnerships between patients and healthcare professionals which will enhance individual patients' ability to self-manage chronic disease.

14 CFR 25.1531 - Maneuvering flight load factors.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Maneuvering flight load factors. 25.1531... Operating Limitations § 25.1531 Maneuvering flight load factors. Load factor limitations, not exceeding the positive limit load factors determined from the maneuvering diagram in § 25.333(b), must be established. ...

Fault detection in reciprocating compressor valves under varying load conditions

NASA Astrophysics Data System (ADS)

Pichler, Kurt; Lughofer, Edwin; Pichler, Markus; Buchegger, Thomas; Klement, Erich Peter; Huschenbett, Matthias

2016-03-01

This paper presents a novel approach for detecting cracked or broken reciprocating compressor valves under varying load conditions. The main idea is that the time frequency representation of vibration measurement data will show typical patterns depending on the fault state. The problem is to detect these patterns reliably. For the detection task, we make a detour via the two dimensional autocorrelation. The autocorrelation emphasizes the patterns and reduces noise effects. This makes it easier to define appropriate features. After feature extraction, classification is done using logistic regression and support vector machines. The method's performance is validated by analyzing real world measurement data. The results will show a very high detection accuracy while keeping the false alarm rates at a very low level for different compressor loads, thus achieving a load-independent method. The proposed approach is, to our best knowledge, the first automated method for reciprocating compressor valve fault detection that can handle varying load conditions.

Acute changes in foot strike pattern and cadence affect running parameters associated with tibial stress fractures.

PubMed

Yong, Jennifer R; Silder, Amy; Montgomery, Kate L; Fredericson, Michael; Delp, Scott L

2018-05-18

Tibial stress fractures are a common and debilitating injury that occur in distance runners. Runners may be able to decrease tibial stress fracture risk by adopting a running pattern that reduces biomechanical parameters associated with a history of tibial stress fracture. The purpose of this study was to test the hypothesis that converting to a forefoot striking pattern or increasing cadence without focusing on changing foot strike type would reduce injury risk parameters in recreational runners. Running kinematics, ground reaction forces and tibial accelerations were recorded from seventeen healthy, habitual rearfoot striking runners while running in their natural running pattern and after two acute retraining conditions: (1) converting to forefoot striking without focusing on cadence and (2) increasing cadence without focusing on foot strike. We found that converting to forefoot striking decreased two risk factors for tibial stress fracture: average and peak loading rates. Increasing cadence decreased one risk factor: peak hip adduction angle. Our results demonstrate that acute adaptation to forefoot striking reduces different injury risk parameters than acute adaptation to increased cadence and suggest that both modifications may reduce the risk of tibial stress fractures. Copyright © 2018 Elsevier Ltd. All rights reserved.

Characterising the reproducibility and reliability of dietary patterns among Yup'ik Alaska Native people.

PubMed

Ryman, Tove K; Boyer, Bert B; Hopkins, Scarlett; Philip, Jacques; O'Brien, Diane; Thummel, Kenneth; Austin, Melissa A

2015-02-28

FFQ data can be used to characterise dietary patterns for diet-disease association studies. In the present study, we evaluated three previously defined dietary patterns--'subsistence foods', market-based 'processed foods' and 'fruits and vegetables'--among a sample of Yup'ik people from Southwest Alaska. We tested the reproducibility and reliability of the dietary patterns, as well as the associations of these patterns with dietary biomarkers and participant characteristics. We analysed data from adult study participants who completed at least one FFQ with the Center for Alaska Native Health Research 9/2009-5/2013. To test the reproducibility of the dietary patterns, we conducted a confirmatory factor analysis (CFA) of a hypothesised model using eighteen food items to measure the dietary patterns (n 272). To test the reliability of the dietary patterns, we used the CFA to measure composite reliability (n 272) and intra-class correlation coefficients for test-retest reliability (n 113). Finally, to test the associations, we used linear regression (n 637). All factor loadings, except one, in CFA indicated acceptable correlations between foods and dietary patterns (r>0·40), and model-fit criteria were >0·90. Composite and test-retest reliability of the dietary patterns were, respectively, 0·56 and 0·34 for 'subsistence foods', 0·73 and 0·66 for 'processed foods', and 0·72 and 0·54 for 'fruits and vegetables'. In the multi-predictor analysis, the dietary patterns were significantly associated with dietary biomarkers, community location, age, sex and self-reported lifestyle. This analysis confirmed the reproducibility and reliability of the dietary patterns in the present study population. These dietary patterns can be used for future research and development of dietary interventions in this underserved population.

Assessment of Cr, Ni and Pb Pollution in Rural Agricultural Soils of Tonalite-Trondjhemite Series in Central India.

PubMed

Shukla, Kriti; Kumar, Bijendra; Agrawal, Rahul; Priyanka, Kumari; Venkatesh, Madavi; Anshumali

2017-06-01

Chromium (Cr), nickel (Ni) and lead (Pb) contamination was investigated in wheat cultivated rain-fed and irrigated rural agricultural soils (n = 31) of Tonalite-Trondjhemite Series in Central India. The soil sampling was carried out by using stratified random sampling method. The mean concentrations of Cr, Ni and Pb were 54.8, 38.1 and 68.9 mg/kg, respectively. The average values of enrichment factor (EF), geoaccumulation index (I geo ) and contamination factor (CF) followed the order as: Pb > Ni > Cr. Distribution patterns of soil parent material and weathering processes govern mineral enrichments, irrespective of rainfed or irrigated agricultural practices. Principal component analysis (PCA) showed strong loading of Cr and Ni (PC1) and Pb and clay (PC3). The strong loading on Cr and Ni indicates soils are originating from basic and volcanic rocks in the study area. The strong loading of Pb and clay indicates Pb is strongly adsorbed on clay minerals and Fe-oxides. The cancer risk (CR) index showed negligible carcinogenic risk to the residing population. However, hazard index (HI) values for children exceed the safe limit (HI > 1) for Cr and Pb. Spatial distribution of pollution load index suggest highest pollution in the northeastern part of the district. The study revealed that geogenically enriched soils of the area are suitable for agricultural activities under present conditions.

Dietary patterns among Norwegian 2-year-olds in 1999 and in 2007 and associations with child and parent characteristics.

PubMed

Kristiansen, Anne Lene; Lande, Britt; Sexton, Joseph Andrew; Andersen, Lene Frost

2013-07-14

Infant and childhood nutrition influences short- and long-term health. The objective of the present paper has been to explore dietary patterns and their associations with child and parent characteristics at two time points. Parents of Norwegian 2-year-olds were, in 1999 (n 3000) and in 2007 (n 2984), invited to participate in a national dietary survey. At both time points, diet was assessed by a semi-quantitative FFQ that also provided information on several child and parent characteristics. A total of 1373 participants in the 1999 sample and 1472 participants in the 2007 sample were included in the analyses. Dietary patterns were identified by principal components analysis and related to child and parent characteristics using the general linear model. Four dietary patterns were identified at each time point. The 'unhealthy' and 'healthy' patterns in 1999 and 2007 showed similarities with regard to loadings of food groups. Both the 'bread and spread-based' pattern in 1999 and the 'traditional' pattern in 2007 had high positive loadings for bread and spreads; however, the 'traditional' pattern did also include positive associations with a warm meal. The last patterns identified in 1999 and in 2007 were not comparable with regard to loadings of food groups. All dietary patterns were significantly associated with one or several child and parent characteristics. In conclusion, the 'unhealthy' patterns in 1999 and in 2007 showed similarities with regard to loadings of food groups and were, at both time points, associated with sex, breastfeeding at 12 months of age, parity, maternal age and maternal work situation.

Frequency effects on the stability of a journal bearing for periodic loading

NASA Technical Reports Server (NTRS)

Vijayaraghavan, D.; Brewe, D. E.

1992-01-01

The stability of a journal bearing is numerically predicted when an unidirectional periodic external load is applied. The analysis is performed using a cavitation algorithm, which mimics the JFO theory by accounting for the mass balance through the complete bearing. Hence, the history of the film is taken into consideration. The loading pattern is taken to be sinusoidal and the frequency of the load cycle is varied. The results are compared with the predictions using Reynolds boundary conditions for both film rupture and reformation. With such comparisons, the need for accurately predicting the cavitation regions for complex loading patterns is clearly demonstrated. For a particular frequency of loading, the effects of mass, amplitude of load vibration and frequency of journal speed are also investigated.

Biomechanical analysis of INFINITY rehabilitation method for treatment of low back pain

PubMed Central

Daniel, Matej; Tomanová, Michaela; Hornová, Jana; Novotná, Iva; Lhotská, Lenka

2017-01-01

[Purpose] Low back pain is a pervasive problem in modern societies. Physical rehabilitation in treatment of low back pain should reduce pain, muscle tension and restore spine stability and balance. The INFINITY® rehabilitation method that is based on a figure of eight movement pattern was proved to be effective in low back pain treatment. The aim of the paper is to estimate the effect of a figure of eight motion on the L5/S1 load and lumbar spine muscle activation in comparison to other motion patterns. [Subjects and Methods] Three-dimensional model of lumbar spine musculoskeletal system is used to simulate effect of various load motion pattern induced by displacement of the center of gravity of the upper body. Four motion patterns were examined: lateral and oblique pendulum-like motion, elliptical motion and figure of eight motion. [Results] The simple pendulum-like and elliptical-like patterns induce harmonic muscle activation and harmonic spinal load. The figure of eight motion pattern creates high-frequency spinal loading that activates remodeling of bones and tendons. The figure of eight pattern also requires muscle activity that differs from harmonic frequency and is more demanding on muscle control and could also improve muscle coordination. [Conclusion] The results of the study indicate that complex motion pattern during INFINITY® rehabilitation might enhance the spine stability by influencing its passive, active and neural components. PMID:28603355

Assessment of a numerical model to reproduce event‐scale erosion and deposition distributions in a braided river

PubMed Central

Measures, R.; Hicks, D. M.; Brasington, J.

2016-01-01

Abstract Numerical morphological modeling of braided rivers, using a physics‐based approach, is increasingly used as a technique to explore controls on river pattern and, from an applied perspective, to simulate the impact of channel modifications. This paper assesses a depth‐averaged nonuniform sediment model (Delft3D) to predict the morphodynamics of a 2.5 km long reach of the braided Rees River, New Zealand, during a single high‐flow event. Evaluation of model performance primarily focused upon using high‐resolution Digital Elevation Models (DEMs) of Difference, derived from a fusion of terrestrial laser scanning and optical empirical bathymetric mapping, to compare observed and predicted patterns of erosion and deposition and reach‐scale sediment budgets. For the calibrated model, this was supplemented with planform metrics (e.g., braiding intensity). Extensive sensitivity analysis of model functions and parameters was executed, including consideration of numerical scheme for bed load component calculations, hydraulics, bed composition, bed load transport and bed slope effects, bank erosion, and frequency of calculations. Total predicted volumes of erosion and deposition corresponded well to those observed. The difference between predicted and observed volumes of erosion was less than the factor of two that characterizes the accuracy of the Gaeuman et al. bed load transport formula. Grain size distributions were best represented using two φ intervals. For unsteady flows, results were sensitive to the morphological time scale factor. The approach of comparing observed and predicted morphological sediment budgets shows the value of using natural experiment data sets for model testing. Sensitivity results are transferable to guide Delft3D applications to other rivers. PMID:27708477

Assessment of a numerical model to reproduce event-scale erosion and deposition distributions in a braided river.

PubMed

Williams, R D; Measures, R; Hicks, D M; Brasington, J

2016-08-01

Numerical morphological modeling of braided rivers, using a physics-based approach, is increasingly used as a technique to explore controls on river pattern and, from an applied perspective, to simulate the impact of channel modifications. This paper assesses a depth-averaged nonuniform sediment model (Delft3D) to predict the morphodynamics of a 2.5 km long reach of the braided Rees River, New Zealand, during a single high-flow event. Evaluation of model performance primarily focused upon using high-resolution Digital Elevation Models (DEMs) of Difference, derived from a fusion of terrestrial laser scanning and optical empirical bathymetric mapping, to compare observed and predicted patterns of erosion and deposition and reach-scale sediment budgets. For the calibrated model, this was supplemented with planform metrics (e.g., braiding intensity). Extensive sensitivity analysis of model functions and parameters was executed, including consideration of numerical scheme for bed load component calculations, hydraulics, bed composition, bed load transport and bed slope effects, bank erosion, and frequency of calculations. Total predicted volumes of erosion and deposition corresponded well to those observed. The difference between predicted and observed volumes of erosion was less than the factor of two that characterizes the accuracy of the Gaeuman et al. bed load transport formula. Grain size distributions were best represented using two φ intervals. For unsteady flows, results were sensitive to the morphological time scale factor. The approach of comparing observed and predicted morphological sediment budgets shows the value of using natural experiment data sets for model testing. Sensitivity results are transferable to guide Delft3D applications to other rivers.

14 CFR 23.473 - Ground load conditions and assumptions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... vertical inertia load factor at the center of gravity of the airplane for the ground load conditions... through the center of gravity. The ground reaction load factor may be equal to the inertia load factor..., these tests must be made under § 23.723(a). (g) No inertia load factor used for design purposes may be...

14 CFR 23.473 - Ground load conditions and assumptions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... vertical inertia load factor at the center of gravity of the airplane for the ground load conditions... through the center of gravity. The ground reaction load factor may be equal to the inertia load factor..., these tests must be made under § 23.723(a). (g) No inertia load factor used for design purposes may be...

14 CFR 23.473 - Ground load conditions and assumptions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... vertical inertia load factor at the center of gravity of the airplane for the ground load conditions... through the center of gravity. The ground reaction load factor may be equal to the inertia load factor..., these tests must be made under § 23.723(a). (g) No inertia load factor used for design purposes may be...

14 CFR 23.473 - Ground load conditions and assumptions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... vertical inertia load factor at the center of gravity of the airplane for the ground load conditions... through the center of gravity. The ground reaction load factor may be equal to the inertia load factor..., these tests must be made under § 23.723(a). (g) No inertia load factor used for design purposes may be...

14 CFR 23.473 - Ground load conditions and assumptions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... vertical inertia load factor at the center of gravity of the airplane for the ground load conditions... through the center of gravity. The ground reaction load factor may be equal to the inertia load factor..., these tests must be made under § 23.723(a). (g) No inertia load factor used for design purposes may be...

Characterizing the Reproducibility and Reliability of Dietary Patterns among Yup’ik Alaska Native People

PubMed Central

Ryman, Tove K.; Boyer, Bert B.; Hopkins, Scarlett; Philip, Jacques; O’Brien, Diane; Thummel, Kenneth; Austin, Melissa A.

2015-01-01

Food frequency questionnaire (FFQ) data can be used to characterize dietary patterns for diet-disease association studies. Among a sample of Yup’ik people from Southwest Alaska, we evaluated three previously defined dietary patterns: “subsistence foods” and market-based “processed foods” and “fruits and vegetables”. We tested the reproducibility and reliability of the dietary patterns and tested associations of the patterns with dietary biomarkers and participant characteristics. We analyzed data from adult study participants who completed at least one FFQ with the Center for Alaska Native Health Research 9/2009–5/2013. To test reproducibility we conducted a confirmatory factor analysis (CFA) of a hypothesized model using 18 foods to measure the dietary patterns (n=272). To test the reliability of the dietary patterns, we used CFA to measure the composite reliability (n=272) and intraclass correlation coefficients for test-retest reliability (n=113). Finally, to test associations we used linear regression (n=637). All CFA factor loadings, except one, indicated acceptable correlations between foods and dietary patterns (r > 0.40) and model fit criteria were greater than 0.90. Composite and test-retest reliability of dietary patterns were respectively 0.56 and 0.34 for subsistence foods, 0.73 and 0.66 for processed foods, and 0.72 and 0.54 for fruits and vegetables. In the multi-predictor analysis, dietary patterns were significantly associated with dietary biomarkers, community location, age, sex, and self-reported lifestyle. This analysis confirmed the reproducibility and reliability of the dietary patterns in this study population. These dietary patterns can be used for future research and development of dietary interventions in this underserved population. PMID:25656871

Facial and ocular deposition of nebulized budesonide: effects of face mask design.

PubMed

Harris, Keith W; Smaldone, Gerald C

2008-02-01

In vivo case reports and in vitro studies have indicated that aerosol therapy using face masks can result in drug deposition on the face and in the eyes, and that face mask design may affect drug delivery. To test different mask/nebulizer combinations for budesonide, a nebulized steroid used to treat pediatric patients with asthma. Using high-performance liquid chromatography, drug delivery (inhaled mass), facial, and ocular deposition of budesonide aerosols were studied in vitro using a ventilated face facsimile (tidal volume, 50 mL; rate, 25 breaths/min, duty cycle 0.4), a tight-fitting test mask, a standard commercial mask, and a prototype mask designed to optimize delivery by reducing particle inertia. Nebulizer insertion into the mask (front loaded vs bottom loaded) was also tested. Particle size was measured by cascade impaction. Pari LC Plus (PARI Respiratory Equipment; Midlothian, VA) and MistyNeb (Allegiance; McGaw Park, IL) nebulizers were tested. Inhaled mass for tight-fitting and prototype masks was similar (13.2 +/- 1.85% vs 14.4 +/- 0.67% [percentage of nebulizer charge], p = 0.58) and significantly greater than for the commercial mask (3.03 +/- 0.26%, p = 0.005). Mask insertion of nebulizer was a key factor (inhaled mass: front loaded vs bottom loaded, 8.23 +/- 0.18% vs 3.03 +/- 0.26%; p = 0.005). Ocular deposition varied by an order of magnitude and was a strong function of mask design (4.77 +/- 0.24% vs 0.35 +/- 0.05%, p = 0.002, tight fitting vs prototype). Particle sizes (7.3 to 9 microm) were larger than previously reported for budesonide. For pediatric breathing patterns, mask design is a key factor defining budesonide delivery to the lungs, face, and eyes. Front-loaded nebulizer mask combinations are more efficient than bottom-loaded systems.

Multimorbidity Patterns in the Elderly: A New Approach of Disease Clustering Identifies Complex Interrelations between Chronic Conditions

PubMed Central

Schäfer, Ingmar; von Leitner, Eike-Christin; Schön, Gerhard; Koller, Daniela; Hansen, Heike; Kolonko, Tina; Kaduszkiewicz, Hanna; Wegscheider, Karl; Glaeske, Gerd; van den Bussche, Hendrik

2010-01-01

Objective Multimorbidity is a common problem in the elderly that is significantly associated with higher mortality, increased disability and functional decline. Information about interactions of chronic diseases can help to facilitate diagnosis, amend prevention and enhance the patients' quality of life. The aim of this study was to increase the knowledge of specific processes of multimorbidity in an unselected elderly population by identifying patterns of statistically significantly associated comorbidity. Methods Multimorbidity patterns were identified by exploratory tetrachoric factor analysis based on claims data of 63,104 males and 86,176 females in the age group 65+. Analyses were based on 46 diagnosis groups incorporating all ICD-10 diagnoses of chronic diseases with a prevalence ≥ 1%. Both genders were analyzed separately. Persons were assigned to multimorbidity patterns if they had at least three diagnosis groups with a factor loading of 0.25 on the corresponding pattern. Results Three multimorbidity patterns were found: 1) cardiovascular/metabolic disorders [prevalence female: 30%; male: 39%], 2) anxiety/depression/somatoform disorders and pain [34%; 22%], and 3) neuropsychiatric disorders [6%; 0.8%]. The sampling adequacy was meritorious (Kaiser-Meyer-Olkin measure: 0.85 and 0.84, respectively) and the factors explained a large part of the variance (cumulative percent: 78% and 75%, respectively). The patterns were largely age-dependent and overlapped in a sizeable part of the population. Altogether 50% of female and 48% of male persons were assigned to at least one of the three multimorbidity patterns. Conclusion This study shows that statistically significant co-occurrence of chronic diseases can be subsumed in three prevalent multimorbidity patterns if accounting for the fact that different multimorbidity patterns share some diagnosis groups, influence each other and overlap in a large part of the population. In recognizing the full complexity of multimorbidity we might improve our ability to predict needs and achieve possible benefits for elderly patients who suffer from multimorbidity. PMID:21209965

Clonazepam release from poly(DL-lactide-co-glycolide) nanoparticles prepared by dialysis method.

PubMed

Nah, J W; Paek, Y W; Jeong, Y I; Kim, D W; Cho, C S; Kim, S H; Kim, M Y

1998-08-01

Aim of this work is to prepare poly(DL-lactide-co-glycolide) (PLGA) nanoparticles by dialysis method without surfactant and to investigate drug loading capacity and drug release. The size of PLGA nanoparticles was 269.9 +/- 118.7 nm in intensity average and the morphology of PLGA nanoparticles was spherical shape from the observation of SEM and TEM. In the effect of drug loading contents on the particle size distribution, PLGA nanoparticles were monomodal pattern with narrow size distribution in the empty and lower drug loading nanoparticles whereas bi- or trimodal pattern was showed in the higher drug loading ones. Release of clonazepam from PLGA nanoparticles with higher drug loading contents was slower than that with lower loading contents.

14 CFR 23.527 - Hull and main float load factors.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hull and main float load factors. 23.527... Water Loads § 23.527 Hull and main float load factors. (a) Water reaction load factors nw must be...=seaplane landing weight in pounds. (6) K1=empirical hull station weighing factor, in accordance with figure...

14 CFR 23.527 - Hull and main float load factors.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Water Loads § 23.527 Hull and main float load factors. (a) Water reaction load factors nw must be... landing cases EC28SE91.005 (b) The following values are used: (1) nw=water reaction load factor (that is, the water reaction divided by seaplane weight). (2) C1=empirical seaplane operations factor equal to 0...

14 CFR 31.23 - Flight load factor.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Flight load factor. 31.23 Section 31.23... STANDARDS: MANNED FREE BALLOONS Strength Requirements § 31.23 Flight load factor. In determining limit load, the limit flight load factor must be at least 1.4. ...

14 CFR 31.23 - Flight load factor.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Flight load factor. 31.23 Section 31.23... STANDARDS: MANNED FREE BALLOONS Strength Requirements § 31.23 Flight load factor. In determining limit load, the limit flight load factor must be at least 1.4. ...

14 CFR 31.23 - Flight load factor.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Flight load factor. 31.23 Section 31.23... STANDARDS: MANNED FREE BALLOONS Strength Requirements § 31.23 Flight load factor. In determining limit load, the limit flight load factor must be at least 1.4. ...

Trabecular architecture of the manual elements reflects locomotor patterns in primates.

PubMed

Matarazzo, Stacey A

2015-01-01

The morphology of trabecular bone has proven sensitive to loading patterns in the long bones and metacarpal heads of primates. It is expected that we should also see differences in the manual digits of primates that practice different methods of locomotion. Primate proximal and middle phalanges are load-bearing elements that are held in different postures and experience different mechanical strains during suspension, quadrupedalism, and knuckle walking. Micro CT scans of the middle phalanx, proximal phalanx and the metacarpal head of the third ray were used to examine the pattern of trabecular orientation in Pan, Gorilla, Pongo, Hylobates and Macaca. Several zones, i.e., the proximal ends of both phalanges and the metacarpal heads, were capable of distinguishing between knuckle-walking, quadrupedal, and suspensory primates. Orientation and shape seem to be the primary distinguishing factors but differences in bone volume, isotropy index, and degree of anisotropy were seen across included taxa. Suspensory primates show primarily proximodistal alignment in all zones, and quadrupeds more palmar-dorsal orientation in several zones. Knuckle walkers are characterized by having proximodistal alignment in the proximal ends of the phalanges and a palmar-dorsal alignment in the distal ends and metacarpal heads. These structural differences may be used to infer locmotor propensities of extinct primate taxa.

The influence of muscle fatigue on electromyogram and plantar pressure patterns as an explanation for the incidence of metatarsal stress fractures.

PubMed

Weist, Roger; Eils, Eric; Rosenbaum, Dieter

2004-12-01

Stress fractures are common overuse injuries in runners and appear most frequently in the metatarsals. To investigate fatigue-related changes in surface electromyographic activity patterns and plantar pressure patterns during treadmill running as potential causative factors for metatarsal stress fractures. Prospective cohort study with repeated measurements. Thirty experienced runners volunteered to participate in a maximally exhaustive run above the anaerobic threshold. Surface electromyographic activity was monitored for 14 muscles, and plantar pressures were measured using an in-shoe monitoring system. Fatigue was documented with blood lactate measurements. The results demonstrated an increased maximal force (5%, P < .01), peak pressure (12%, P < .001), and impulse (9%, P < .01) under the second and third metatarsal head and under the medial midfoot (force = 7%, P < .05; pressure = 6%, P < .05; impulse = 17%, P < .01) toward the end of the fatiguing run. Contact area and contact time were only slightly affected. The mean electromyographic activity was significantly reduced in the medial gastrocnemius (-9%, P < .01), lateral gastrocnemius (-12%, P < .01), and soleus (-9%, P < .001) muscles. The demonstrated alteration of the rollover process with an increased forefoot loading may help to explain the incidence of stress fractures of the metatarsals under fatiguing loading conditions.

Mitochondrial DNA plays an equal role in influencing female and male longevity in centenarians.

PubMed

He, Yong-Han; Lu, Xiang; Tian, Jiao-Yang; Yan, Dong-Jing; Li, Yu-Chun; Lin, Rong; Perry, Benjamin; Chen, Xiao-Qiong; Yu, Qin; Cai, Wang-Wei; Kong, Qing-Peng

2016-10-01

The mitochondrion is a double membrane-bound organelle which plays important functional roles in aging and many other complex phenotypes. Transmission of the mitochondrial genome in the matrilineal line causes the evolutionary selection sieve only in females. Theoretically, beneficial or neutral variations are more likely to accumulate and be retained in the female mitochondrial genome during evolution, which may be an initial trigger of gender dimorphism in aging. The asymmetry of evolutionary processes between gender could lead to males and females aging in different ways. If so, gender specific variation loads could be an evolutionary result of maternal heritage of mitochondrial genomes, especially in centenarians who live to an extreme age and are considered as good models for healthy aging. Here, we tested whether the mitochondrial variation loads were associated with altered aging patterns by investigating the mtDNA haplogroup distribution and genetic diversity between female and male centenarians. We found no evidence of differences in aging patterns between genders in centenarians. Our results indicate that the evolutionary consequence of gender dimorphism in mitochondrial genomes is not a factor in the altered aging patterns in human, and that mitochondrial DNA contributes equally to longevity in males and females. Copyright © 2016 Elsevier Inc. All rights reserved.

Loading of PAX3 to Mitotic Chromosomes Is Mediated by Arginine Methylation and Associated with Waardenburg Syndrome.

PubMed

Wu, Tsu-Fang; Yao, Ya-Li; Lai, I-Lu; Lai, Chien-Chen; Lin, Pei-Lun; Yang, Wen-Ming

2015-08-14

PAX3 is a transcription factor critical to gene regulation in mammalian development. Mutations in PAX3 are associated with Waardenburg syndrome (WS), but the mechanism of how mutant PAX3 proteins cause WS remains unclear. Here, we found that PAX3 loads on mitotic chromosomes using its homeodomain. PAX3 WS mutants with mutations in homeodomain lose the ability to bind mitotic chromosomes. Moreover, loading of PAX3 on mitotic chromosomes requires arginine methylation, which is regulated by methyltransferase PRMT5 and demethylase JMJD6. Mutant PAX3 proteins that lose mitotic chromosome localization block cell proliferation and normal development of zebrafish. These results reveal the molecular mechanism of PAX3s loading on mitotic chromosomes and the importance of this localization pattern in normal development. Our findings suggest that PAX3 WS mutants interfere with the normal functions of PAX3 in a dominant negative manner, which is important to the understanding of the pathogenesis of Waardenburg syndrome. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

The influence of impact direction and axial loading on the bone fracture pattern.

PubMed

Cohen, Haim; Kugel, Chen; May, Hila; Medlej, Bahaa; Stein, Dan; Slon, Viviane; Brosh, Tamar; Hershkovitz, Israel

2017-08-01

The effect of the direction of the impact and the presence of axial loading on fracture patterns have not yet been established in experimental 3-point bending studies. To reveal the association between the direction of the force and the fracture pattern, with and without axial loading. A Dynatup Model POE 2000 (Instron Co.) low energy pendulum impact machine was utilized to apply impact loading on fresh pig femoral bones (n=50). The bone clamp shaft was adjusted to position the bone for three-point bending with and without additional bone compression. Four different directions of the force were applied: anterior, posterior, lateral, and medial. The impacted aspect can be distinguished from the non-impacted aspects based on the fracture pattern alone (the most fractured one); the impact point can be identified on bare bones (the area from which all oblique lines radiate and/or the presence of a chip fragment). None of our experiments (with and without compression) yielded a "true" butterfly fracture, but instead, oblique radiating lines emerged from the point of impact (also known as "false" butterfly). Impacts on the lateral and anterior aspects of the bones produce more and longer fracture lines than impacts on the contralateral side; bones subjected to an impact with axial loading are significantly more comminuted and fragmented. Under axial loading, the number of fracture lines is independent of the impact direction. Our study presents an experimental model for fracture analysis and shows that the impact direction and the presence of axial loading during impact significantly affect the fracture pattern obtained. Copyright © 2017 Elsevier B.V. All rights reserved.

Back pain is associated with changes in loading pattern throughout forward and backward bending.

PubMed

Shum, Gary L K; Crosbie, Jack; Lee, Raymond Y W

2010-12-01

Experimental study to determine the kinetics of the lumbar spine (LS) and hips during forward and backward bending. To investigate the effects of back pain, with and without a positive straight leg raise (SLR) sign, on the loading patterns in the LS and hip during forward and backward bending. Forward and backward bending are important components of many functional activities and are part of routine clinical examination. However, there is a little information about the loading patterns during forward and backward bending in people with back pain with or without a positive SLR sign. Twenty asymptomatic participants, 20 back pain participants, and 20 participants with back pain and a positive SLR sign performed 3 continuous cycles of forward and backward bending. Electromagnetic sensors were attached to body segments to measure their kinematics while 2 nonconductive force plates gathered ground reaction force data. A biomechanical model was used to determine the loading pattern in LS and hips. Although the loading on the LS at the end of the range decreased significantly, the loading at the early and middle ranges of forward bending actually increased significantly in people with back pain, especially in those with positive SLR sign. This suggests that resistance to movement is significantly increased in people with back pain during this movement. This study suggested that it is not sufficient to study the spine at the end of range only, but a complete description of the loading patterns throughout the range is required. Although the maximum range of motion of the spine is reduced in people with back pain, there is a significant increase in the moment acting through the range, particularly in those with a positive SLR sign.

Evaluation of Amorphous Transformer by Optimum Capacity Selection based on the Load Curve Pattern of Customers

NASA Astrophysics Data System (ADS)

Takagi, Masaaki; Yamamoto, Hiromi; Yamaji, Kenji

Energy loss in transformer is composed of no-load loss and load loss. No-load loss of amorphous transformer (i.e. amorphous metal-based transformer) is less by about 70% compared with traditional transformers (e.g. silicon steel-based transformer). However, amorphous transformers have disadvantages of high cost and high load loss parameter compared with traditional transformers. Furthermore, there are varieties of transformer capacities, and the customers who would buy new transformer have many choices. In this paper, the authors propose an algorithm for optimum transformer selection based on the load curve patterns of customers. It is possible to select the capacity that minimizes the total cost by measuring equivalent load Qe that is the root mean square of load. It becomes clear that amorphous transformer is effective in achieving substantial energy saving compared with traditional transformer.

Impact of Climate Variability and Landscape Patterns on Water Budget and Nutrient Loads in a Peri-urban Watershed: A Coupled Analysis Using Process-based Hydrological Model and Landscape Indices.

PubMed

Li, Chongwei; Zhang, Yajuan; Kharel, Gehendra; Zou, Chris B

2018-06-01

Nutrient discharge into peri-urban streams and reservoirs constitutes a significant pressure on environmental management, but quantitative assessment of non-point source pollution under climate variability in fast changing peri-urban watersheds is challenging. Soil and Water Assessment Tool (SWAT) was used to simulate water budget and nutrient loads for landscape patterns representing a 30-year progression of urbanization in a peri-urban watershed near Tianjin metropolis, China. A suite of landscape pattern indices was related to nitrogen (N) and phosphorous (P) loads under dry and wet climate using CANOCO redundancy analysis. The calibrated SWAT model was adequate to simulate runoff and nutrient loads for this peri-urban watershed, with Nash-Sutcliffe coefficient (NSE) and coefficient of determination (R 2 ) > 0.70 and percentage bias (PBIAS) between -7 and +18 for calibration and validation periods. With the progression of urbanization, forest remained the main "sink" landscape while cultivated and urban lands remained the main "source" landscapes with the role of orchard and grassland being uncertain and changing with time. Compared to 1984, the landscape use pattern in 2013 increased nutrient discharge by 10%. Nutrient loads modelled under wet climate were 3-4 times higher than that under dry climate for the same landscape pattern. Results indicate that climate change could impose a far greater impact on runoff and nutrient discharge in a peri-urban watershed than landscape pattern change.

Impact of Climate Variability and Landscape Patterns on Water Budget and Nutrient Loads in a Peri-urban Watershed: A Coupled Analysis Using Process-based Hydrological Model and Landscape Indices

NASA Astrophysics Data System (ADS)

Li, Chongwei; Zhang, Yajuan; Kharel, Gehendra; Zou, Chris B.

2018-06-01

Nutrient discharge into peri-urban streams and reservoirs constitutes a significant pressure on environmental management, but quantitative assessment of non-point source pollution under climate variability in fast changing peri-urban watersheds is challenging. Soil and Water Assessment Tool (SWAT) was used to simulate water budget and nutrient loads for landscape patterns representing a 30-year progression of urbanization in a peri-urban watershed near Tianjin metropolis, China. A suite of landscape pattern indices was related to nitrogen (N) and phosphorous (P) loads under dry and wet climate using CANOCO redundancy analysis. The calibrated SWAT model was adequate to simulate runoff and nutrient loads for this peri-urban watershed, with Nash-Sutcliffe coefficient (NSE) and coefficient of determination ( R 2) > 0.70 and percentage bias (PBIAS) between -7 and +18 for calibration and validation periods. With the progression of urbanization, forest remained the main "sink" landscape while cultivated and urban lands remained the main "source" landscapes with the role of orchard and grassland being uncertain and changing with time. Compared to 1984, the landscape use pattern in 2013 increased nutrient discharge by 10%. Nutrient loads modelled under wet climate were 3-4 times higher than that under dry climate for the same landscape pattern. Results indicate that climate change could impose a far greater impact on runoff and nutrient discharge in a peri-urban watershed than landscape pattern change.

Suspended sediment load in northwestern South America (Colombia): A new view on variability and fluxes into the Caribbean Sea

NASA Astrophysics Data System (ADS)

Restrepo López, Juan Camilo; Orejarena R, Andrés F.; Torregroza, Ana Carolina

2017-12-01

Monthly averaged suspended sediment load data from seven rivers in northern Colombia (Caribbean alluvial plain) draining into the Caribbean Sea were analyzed to quantify magnitudes, estimate long-term trends, and evaluate variability patterns of suspended sediment load. Collectively these rivers deliver an average of around 146.3 × 106 t yr-1 of suspended sediments to the Colombian Caribbean coast. The largest sediment supply is provided by the Magdalena River, with a mean suspended sediment load of 142.6 × 106 t yr-1, or 38% of the total fluvial discharge estimated for the whole Caribbean littoral zone. Between 2000 and 2010, the annual suspended sediment load of these rivers increased by as much as 36%. Wavelet spectral analyses identified periods of intense variability between 1987-1990 and 1994-2002, where major oscillation processes appeared simultaneously. The semi-annual, annual and quasi-decadal bands are the main factors controlling suspended sediment load variability in fluvial systems, whereas the quasi-biennial and interannual bands constitute second-order sources of variability. The climatic and oceanographic drivers of the oscillations identified through wavelet spectral analyses define a signal of medium-long-term variability for the suspended sediment load, while the physiographic and environmental characteristics of the basins determine their ability to magnify, attenuate or modify this signal.

Effect of physical property of supporting media and variable hydraulic loading on hydraulic characteristics of advanced onsite wastewater treatment system.

PubMed

Sharma, Meena Kumari; Kazmi, Absar Ahmad

2015-01-01

A laboratory-scale study was carried out to investigate the effects of physical properties of the supporting media and variable hydraulic shock loads on the hydraulic characteristics of an advanced onsite wastewater treatment system. The system consisted of two upflow anaerobic reactors (a septic tank and an anaerobic filter) accommodated within a single unit. The study was divided into three phases on the basis of three different supporting media (Aqwise carriers, corrugated ring and baked clay) used in the anaerobic filter. Hydraulic loadings were based on peak flow factor (PFF), varying from one to six, to simulate the actual conditions during onsite wastewater treatment. Hydraulic characteristics of the system were identified on the basis of residence time distribution analyses. The system showed a very good hydraulic efficiency, between 0.86 and 0.93, with the media of highest porosity at the hydraulic loading of PFF≤4. At the higher hydraulic loading of PFF 6 also, an appreciable hydraulic efficiency of 0.74 was observed. The system also showed good chemical oxygen demand and total suspended solids removal efficiency of 80.5% and 82.3%, respectively at the higher hydraulic loading of PFF 6. Plug-flow dispersion model was found to be the most appropriate one to describe the mixing pattern of the system, with different supporting media at variable loading, during the tracer study.

Features of lymphatic dysfunction in compressed skin tissues - Implications in pressure ulcer aetiology.

PubMed

Gray, Robert J; Voegeli, David; Bader, Dan L

2016-02-01

Impaired lymph formation and clearance has previously been proposed as a contributory factor in the development of pressure ulcers. The present study has been designed to trial fluorescence lymphangiography for establishing how lymphatic function is altered under a clinically relevant form of mechanical loading. Lymph formation and clearance was traced in both forearms by an intradermal injection of indocyanine green (ICG) (50 μl, 0.05%w/v), imaged using a commercial near-infrared fluorescence imaging unit (Fluobeam(®) 800). External uniaxial loading equivalent to a pressure of 60 mmHg was applied for 45 min in one arm using a custom-built indenter. Loading was associated with a decreased frequency of normal directional drainage (DD) of ICG within delineated vessels, both immediately after loading and 45 min thereafter. Loading was also associated with non-directional drainage (NDD) of ICG within the interstitium. Signal intensity within NDD was often greatest at areas of stress concentration, producing a 'halo pattern', corresponding to the rounded edges of the indenter. These results suggest that loading skin with a clinically relevant magnitude of pressure alters both lymph formation and clearance. Further work to quantify impaired clearance under mechanical loading could provide valuable insight into their involvement in the development of pressure ulcers. Copyright © 2016 Tissue Viability Society. Published by Elsevier Ltd. All rights reserved.

Trends In Nutrient and Sediment Concentrations and Loads In Major River Basins of the South-Central United States, 1993-2004

USGS Publications Warehouse

Rebich, Richard A.; Demcheck, Dennis K.

2008-01-01

Nutrient and sediment data collected at 115 sites by Federal and State agencies from 1993 to 2004 were analyzed by the U.S. Geological Survey to determine trends in concentrations and loads for selected rivers and streams that drain into the northwestern Gulf of Mexico from the south-central United States, specifically from the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf Basins. Trends observed in the study area were compared to determine potential regional patterns and to determine cause-effect relations with trends in hydrologic and human-induced factors such as nutrient sources, streamflow, and implementation of best management practices. Secondary objectives included calculation of loads and yields for the study period as a basis for comparing the delivery of nutrients and sediment to the northwestern Gulf of Mexico from the various rivers within the study area. In addition, loads were assessed at seven selected sites for the period 1980-2004 to give hydrologic perspective to trends in loads observed during 1993-2004. Most study sites (about 64 percent) either had no trends or decreasing trends in streamflow during the study period. The regional pattern of decreasing trends in streamflow during the study period appeared to correspond to moist conditions at the beginning of the study period and the influence of three drought periods during the study period, of which the most extreme was in 2000. Trend tests were completed for ammonia at 49 sites, for nitrite plus nitrate at 69 sites, and for total nitrogen at 41 sites. For all nitrogen constituents analyzed, no trends were observed at half or more of the sites. No regional trend patterns could be confirmed because there was poor spatial representation of the trend sites. Decreasing trends in flow-adjusted concentrations of ammonia were observed at 25 sites. No increasing trends in concentrations of ammonia were noted at any sites. Flow-adjusted concentrations of nitrite plus nitrate decreased at 7 sites and increased at14 sites. Flow-adjusted concentrations of total nitrogen decreased at 2 sites and increased at 12 sites. Improvements to municipal wastewater treatment facilities contributed to the decline of ammonia concentrations at selected sites. Notable increasing trends in nitrite plus nitrate and total nitrogen at selected study sites were attributed to both point and nonpointsources. Trend patterns in total nitrogen generally followed trend patterns in nitrite plus nitrate, which was understandable given that nitrite plus nitrate loads generally were 70-90 percent of the total nitrogen loads at most sites. Population data were used as a surrogate to understand the relation between changes in point sources and nutrient trends because data from wastewater treatment plants were inconsistent for this study area. Although population increased throughout the study area during the study period, there was no observed relation between increasing trends in nitrogen in study area streams and increasing trends in population. With respect to other nitrogen sources, statistical results did suggest that increasing trends in nitrogen could be related to increasing trends in nitrogen from either commercial fertilizer use and/or land application of manure. Loads of ammonia, nitrite plus nitrate, and total nitrogen decreased during the study period, but some trends in nitrogen loads were part of long-term decreases since 1980. For example, ammonia loads were shown to decrease at nearly all sites over the past decade, but at selected sites, these decreasing trends were part of much longer trends since 1980. The Mississippi and Atchafalaya Rivers contributed the highest nitrogen loads to the northwestern Gulf of Mexico as expected; however, nitrogen yields from smaller rivers had similar or higher yields than yields from the Mississippi River. Trend tests were completed for orthophosphorus at 34 sites and for total phosphorus at 52 sites. No trends were observed in abo

Effects of load carrying on metabolic cost and hindlimb muscle dynamics in guinea fowl (Numida meleagris)

PubMed Central

McGowan, C. P.; Duarte, H. A.; Main, J. B.; Biewener, A. A.

2008-01-01

The goal of this study was to test whether the contractile patterns of two major hindlimb extensors of guinea fowl are altered by load-carrying exercise. We hypothesized that changes in contractile pattern, specifically a decrease in muscle shortening velocity or enhanced stretch activation, would result in a reduction in locomotor energy cost relative to the load carried. We also anticipated that changes in kinematics would reflect underlying changes in muscle strain. Oxygen consumption, muscle activation intensity, and fascicle strain rate were measured over a range of speeds while animals ran unloaded vs. when they carried a trunk load equal to 22% of their body mass. Our results showed that loading produced no significant (P > 0.05) changes in kinematic patterns at any speed. In vivo muscle contractile strain patterns in the iliotibialis lateralis pars postacetabularis and the medial head of the gastrocnemius showed a significant increase in active stretch early in stance (P < 0.01), but muscle fascicle shortening velocity was not significantly affected by load carrying. The rate of oxygen consumption increased by 17% (P < 0.01) during loaded conditions, equivalent to 77% of the relative increase in mass. Additionally, relative increases in EMG intensity (quantified as mean spike amplitude) indicated less than proportional recruitment, consistent with force enhancement via stretch activation, in the proximal iliotibialis lateralis pars postacetabularis; however, a greater than proportional increase in the medial gastrocnemius was observed. As a result, when averaged for the two muscles, EMG intensity increased in direct proportion to the fractional increase in load carried. PMID:16809624

Dry etch challenges for CD shrinkage in memory process

NASA Astrophysics Data System (ADS)

Matsushita, Takaya; Matsumoto, Takanori; Mukai, Hidefumi; Kyoh, Suigen; Hashimoto, Kohji

2015-03-01

Line pattern collapse attracts attention as a new problem of the L&S formation in sub-20nm H.P feature. Line pattern collapse that occurs in a slight non-uniformity of adjacent CD (Critical dimension) space using double patterning process has been studied with focus on micro-loading effect in Si etching. Bias RF pulsing plasma etching process using low duty cycle helped increase of selectivity Si to SiO2. In addition to the effect of Bias RF pulsing process, the thin mask obtained from improvement of selectivity has greatly suppressed micro-loading in Si etching. However it was found that micro-loading effect worsen again in sub-20nm space width. It has been confirmed that by using cycle etch process to remove deposition with CFx based etching micro-loading effect could be suppressed. Finally, Si etching process condition using combination of results above could provide finer line and space without "line pattern collapse" in sub-20nm.

Psychometric evaluation of dietary self-efficacy and outcome expectation scales in female college freshmen.

PubMed

Kedem, Leia E; Evans, Ellen M; Chapman-Novakofski, Karen

2014-11-01

Lifestyle interventions commonly measure psychosocial beliefs as precursors to positive behavior change, but often overlook questionnaire validation. This can affect measurement accuracy if the survey has been developed for a different population, as differing behavioral influences may affect instrument validity. The present study aimed to explore psychometric properties of self-efficacy and outcome expectation scales-originally developed for younger children-in a population of female college freshmen (N = 268). Exploratory principal component analysis was used to investigate underlying data patterns and assess validity of previously published subscales. Composite scores for reliable subscales (Cronbach's α ≥ .70) were calculated to help characterize self-efficacy and outcome expectation beliefs in this population. The outcome expectation factor structure clearly comprised of positive (α = .81-.90) and negative outcomes (α = .63-.67). The self-efficacy factor structure included themes of motivation and effort (α = .75-.94), but items pertaining to hunger and availability cross-loaded often. Based on cross-loading patterns and low Cronbach's alpha values, respectively, self-efficacy items regarding barriers to healthy eating and negative outcome expectation items should be refined to improve reliability. Composite scores suggested that eating healthfully was associated with positive outcomes, but self-efficacy to do so was lower. Thus, dietary interventions for college students may be more successful by including skill-building activities to enhance self-efficacy and increase the likelihood of behavior change. © The Author(s) 2014.

Evaluation of Limb Load Asymmetry Using Two New Mathematical Models

PubMed Central

Kumar, Senthil NS; Omar, Baharudin; Joseph, Leonard H.; Htwe, Ohnmar; Jagannathan, K.; Hamdan, Nor M Y; Rajalakshmi, D.

2015-01-01

Quantitative measurement of limb loading is important in orthopedic and neurological rehabilitation. In current practice, mathematical models such as Symmetry index (SI), Symmetry ratio (SR), and Symmetry angle (SA) are used to quantify limb loading asymmetry. Literatures have identified certain limitations with the above mathematical models. Hence this study presents two new mathematical models Modified symmetry index (MSI) and Limb loading error (LLE) that would address these limitations. Furthermore, the current mathematical models were compared against the new model with the goal of achieving a better model. This study uses hypothetical data to simulate an algorithmic preliminary computational measure to perform with all numerical possibilities of even and uneven limb loading that can occur in human legs. Descriptive statistics are used to interpret the limb loading patterns: symmetry, asymmetry and maximum asymmetry. The five mathematical models were similar in analyzing symmetry between limbs. However, for asymmetry and maximum asymmetry data, the SA and SR values do not give any meaningful interpretation, and SI gives an inflated value. The MSI and LLE are direct, easy to interpret and identify the loading patterns with the side of asymmetry. The new models are notable as they quantify the amount and side of asymmetry under different loading patterns. PMID:25716372

Relationship between dietary intake and the development of type 2 diabetes in a Chinese population: the Hong Kong Dietary Survey.

PubMed

Yu, Ruby; Woo, Jean; Chan, Ruth; Sham, Aprille; Ho, Suzanne; Tso, Annette; Cheung, Bernard; Lam, Tai Hing; Lam, Karen

2011-07-01

To study the relationship between dietary intake and the development of type 2 diabetes among Chinese adults. A prospective cohort study. Dietary assessment was carried out using a validated FFQ. Principal component analysis was used to identify dietary patterns. Dietary glycaemic load and variety of snacks were also calculated. A hospital-based centre at the Queen Mary Hospital in Hong Kong SAR, China. A total of 1010 Chinese adults aged 25-74 years who participated in a territory-wide dietary and cardiovascular risk factor prevalence survey in 1995-1996 were followed up for 9-14 years for the development of diabetes. A total of 690 (68·3 %) individuals completed follow-up during 2005-2008 and seventy-four cases of diabetes were identified over the follow-up period. Four dietary patterns were identified ('more snacks and drinks', 'more vegetables, fruits and fish', 'more meat and milk products' and 'more refined grains'). After adjustment for age, sex, BMI, waist-to-hip ratio, smoking, alcohol intake, participation in exercise/sports and family history of diabetes, the more vegetables, fruits and fish pattern was associated with a 14 % lower risk (OR per 1 sd increase in score = 0·76; 95 % CI 0·58, 0·99), whereas the more meat and milk products pattern was associated with a 39 % greater risk of diabetes (OR per 1 sd increase in score = 1·39; 95 % CI 1·04, 1·84). Dietary glycaemic load, rice intake, snack intake and variety of snacks were not independently associated with diabetes. The more vegetables, fruits and fish pattern was associated with reduced risk and the more meat and milk products pattern was associated with an increased risk of diabetes.

Personality and the latent structure of PTSD comorbidity

PubMed Central

Miller, Mark W.; Wolf, Erika J.

2012-01-01

This study examined the structure of PTSD comorbidity and its relationship to personality in a sample of 214 veterans using data from diagnostic interviews and the Multidimensional Personality Questionnaire-Brief Form (MPQ-BF; Patrick, Curtin, & Tellegen, 2002). Confirmatory factor analyses supported a three factor model composed of Externalizing, Fear and Distress factors. Analyses that examined the location of borderline personality disorder revealed significant cross-loadings for this disorder on both Externalizing and Distress. Structural equation models showed trait negative emotionality to be significantly related to all three comorbidity factors whereas positive emotionality and constraint evidenced specific associations with Distress and Externalizing, respectively. These results shed new light on the location of borderline personality disorder within the internalizing/externalizing model and clarify the relative influence of broad dimensions of personality on patterns of comorbidity. PMID:22480716

Different compositions of pharmaceuticals in Dutch and Belgian rivers explained by consumption patterns and treatment efficiency.

PubMed

ter Laak, Thomas L; Kooij, Pascal J F; Tolkamp, Harry; Hofman, Jan

2014-11-01

In the current study, 43 pharmaceuticals and 18 transformation products were studied in the river Meuse at the Belgian-Dutch border and four tributaries of the river Meuse in the southern part of the Netherlands. The tributaries originate from Belgian, Dutch and mixed Dutch and Belgian catchments. In total, 23 pharmaceuticals and 13 transformation products were observed in samples of river water collected from these rivers. Observed summed concentrations of pharmaceuticals and transformation products in river water ranged from 3.5 to 37.8 μg/L. Metformin and its transformation product guanylurea contributed with 53 to 80 % to this concentration, illustrating its importance on a mass basis. Data on the flow rate of different rivers and demographics of the catchments enabled us to calculate daily per capita loads of pharmaceuticals and transformation products. These loads were linked to sales data of pharmaceuticals in the catchment. Simple mass balance modelling accounting for human excretion and removal by sewage treatment plants revealed that sales could predict actual loads within a factor of 3 for most pharmaceuticals. Rivers that originated from Belgian and mixed Dutch and Belgian catchments revealed significantly higher per capita loads of pharmaceuticals (16.0 ± 2.3 and 15.7 ± 2.1 mg/inhabitant/day, respectively) than the Dutch catchment (8.7 ± 1.8 mg/inhabitant/day). Furthermore, the guanylurea/metformin ratio was significantly lower in waters originating from Belgium (and France) than in those from the Netherlands, illustrating that sewage treatment in the Belgian catchment is less efficient in transforming metformin into guanylurea. In summary, the current study shows that consumption-based modelling is suitable to predict environmental loads and concentrations. Furthermore, different consumption patterns and wastewater treatment efficiency are clearly reflected in the occurrence and loads of pharmaceuticals in regional rivers.

Effects of Aerosol on Atmospheric Dynamics and Hydrologic Processes During Boreal Spring and Summer

NASA Technical Reports Server (NTRS)

Lau, William K. M.; Kim, M. K.; Kim, K. M.; Chin, Mian

2005-01-01

Global and regional climate impacts of present-day aerosol loading during boreal spring are investigated using the NASA finite volume General Circulation Model (fvGCM). Three-dimensional distributions of loadings of five species of tropospheric aerosols, i.e., sulfate, black carbon, organic carbon, soil dust, and sea salt are prescribed from outputs of the Goddard Ozone Chemistry Aerosol Radiation and Transport model (GOCART). The aerosol loadings are used to calculate the extinction coefficient, single scattering albedo, and asymmetric factor at eleven spectral wavelengths in the radiative transfer code. We find that aerosol-radiative forcing during boreal spring excites a wavetrain-like pattern in tropospheric temperature and geopotential height that emanates from Northern Africa, through Eurasia, to northeastern Pacific. Associated with the teleconnection is strong surface cooling over regions with large aerosol loading, i.e., China, India, and Africa. Low-to-mid tropospheric heating due to shortwave absorption is found in regions with large loading of dust (Northern Africa, and central East Asia), and black carbon (South and East Asia). In addition pronounced surface cooling is found over the Caspian Sea and warming over Eurasian and northeastern Asia, where aerosol loadings are relatively low. These warming and cooling are components of teleconnection pattern produced primarily by atmospheric heating from absorbing aerosols, i.e., dust from North Africa and black carbon from South and East Asia. Effects of aerosols on atmospheric hydrologic cycle in the Asian monsoon region are also investigated. Results show that absorbing aerosols, i.e., black carbon and dust, induce large-scale upper-level heating anomaly over the Tibetan Plateau in April and May, ushering in an early onset of the Indian summer monsoon. Absorbing aerosols also enhance lower-level heating and anomalous ascent over northern India, intensifying the Indian monsoon. Overall, the aerosol-induced large-scale surface tempera- cooling leads to a reduction of monsoon rainfall over the East Asia continent, and adjacent oceanic regions.

Effects of Aerosol on Atmospheric Dynamics and Hydrologic Processes during Boreal Spring and Summer

NASA Technical Reports Server (NTRS)

Lau, William K. M.; Kim, M. K.; Chin, Mian; Kim, K. M.

2005-01-01

Global and regional climate impacts of present-day aerosol loading during boreal spring are investigated using the NASA finite volume General Circulation Model (fvGCM). Three-dimensional distributions of loadings of five species of tropospheric aerosols, i.e., sulfate, black carbon, organic carbon, soil dust, and sea salt are prescribed from outputs of the Goddard Ozone Chemistry Aerosol Radiation and Transport model (GOCART). The aerosol loadings are used to calculate the extinction coefficient, single scattering albedo, and asymmetric factor at eleven spectral wavelengths in the radiative transfer code. We find that aerosol-radiative forcing during boreal spring excites a wavetrain-like pattern in tropospheric temperature and geopotential height that emanates from Northern Africa, through Eurasia, to northeastern Pacific. Associated with the teleconnection is strong surface cooling over regions with large aerosol loading, i.e., China, India, and Africa. Low-to-mid tropospheric heating due to shortwave absorption is found in regions with large loading of dust (Northern Africa, and central East Asia), and black carbon (South and East Asia). In addition pronounced surface cooling is found over the Caspian Sea and warming over Eurasian and northeastern Asia, where aerosol loadings are relatively low. These warming and cooling are components of teleconnection pattern produced primarily by atmospheric heating from absorbing aerosols, i.e., dust from North Africa and.black carbon from South and East Asia. Effects of aerosols on atmospheric hydrologic cycle in the Asian monsoon region are also investigated. Results show that absorbing aerosols, i.e., black carbon and dust, induce large-scale upper-level heating anomaly over the Tibetan Plateau in April and May, ushering in an early onset of the Indian summer monsoon. Absorbing aerosols also enhance lower-level heating and anomalous ascent over northern India, intensifying the Indian monsoon. Overall, the aerosol-induced large-scale surface temperature cooling leads to a reduction of monsoon rainfall over the East Asia continent, and adjacent oceanic regions.

Sex-biased phoretic mite load on two seaweed flies: Coelopa frigida and Coelopa pilipes.

PubMed

Gilburn, Andre S; Stewart, Katie M; Edward, Dominic A

2009-12-01

Two hypotheses explain male-biased parasitism. Physiological costs of male sexually selected characteristics can reduce immunocompetence. Alternatively, ecological differences could generate male-biased parasitism. One method of comparing the importance of the two theories is to investigate patterns of phoresy, which are only likely to be generated by ecological rather than immunological differences between the sexes. Here we studied the pattern of phoresy of the mite, Thinoseius fucicola, on two species of seaweed fly hosts, Coelopa frigida and Coelopa pilipes. We found a highly male-biased pattern of phoresy of T. fucicola on both species. These are the first reported instances of sex-biased phoresy in a solely phoretic parasite. We also show the first two cases of size-biased phoresy. We suggest that ecological factors, particularly, male mate searching, generated male biased patterns of phoresy. We highlight the potential importance of studies of phoresy in determining the relative roles of the immunocompetence and ecological theories in generating male-biased parasitism. We suggest that more studies of patterns of phoresy are carried out to allow detailed comparisons with patterns of parasitism.

Confirmatory Factor Analysis of the Bases of Leader Power: First-Order Factor Model and Its Invariance Across Groups.

PubMed

Rahim, M A; Magner, N R

1996-10-01

Confirmatory factor analyses of data (from five samples: N = 308 accountants and finance professionals, N = 578 management and non-management employees, and N = 588 employed management students in the U.S.; N = 728 management and non-management employees in S. Korea, N = 250 management and non-management bank employees in Bangladesh) on the 29 items of the Rahim Leader Power Inventory were performed with LISREL 7. The results provided support for the convergent and discriminant validities of the subscales measuring the five bases of leader power (coercive, reward, legitimate, expert, and referent), and the invariance of factor pattern and factor loadings across organizational levels and the three American samples. Additional analysis indicated that leader power profiles differed across the three national cultures represented in the study.

Plantar loading and foot-strike pattern changes with speed during barefoot running in those with a natural rearfoot strike pattern while shod.

PubMed

Cooper, Danielle M; Leissring, Sarah K; Kernozek, Thomas W

2015-06-01

Claims of injury reduction related to barefoot running has resulted in interest from the running public; however, its risks are not well understood for those who typically wear cushioned footwear. Examine how plantar loading changes during barefoot running in a group of runners that ordinarily wear cushioned footwear and demonstrate a rearfoot strike pattern (RFSP) without cueing or feedback alter their foot strike pattern and plantar loading when asked to run barefoot at different speeds down a runway. Forty-one subjects ran barefoot at three different speeds across a pedography platform which collected plantar loading variables for 10 regions of the foot; data were analyzed using two-way mixed multivariate analysis of variance (MANOVA). A significant foot strike position (FSP)×speed interaction in each of the foot regions indicated that plantar loading differed based on FSP across the different speeds. The RFSP provided the highest total forces across the foot while the pressures displayed in subjects with a non-rearfoot strike pattern (NRFSP) was more similar between each of the metatarsals. The majority of subjects ran barefoot with a NRFSP and demonstrated lower total forces and more uniform force distribution across the metatarsal regions. This may have an influence in injuries sustained in barefoot running. Copyright © 2015 Elsevier Ltd. All rights reserved.

14 CFR 25.527 - Hull and main float load factors.

Code of Federal Regulations, 2011 CFR

2011-01-01

... float load factors. (a) Water reaction load factors n W must be computed in the following manner: (1... following values are used: (1) n W=water reaction load factor (that is, the water reaction divided by...

[A study of behavior patterns between smokers and nonsmokers].

PubMed

Kim, H S

1990-04-01

Clinical and epidemiologic studies of coronary heart disease (CHD) have from time to time over the last three decades found associations between prevalence of CHD and behavioral attributes and cigarette smoking. The main purpose of this study is reduced to major risk factor of coronary heart disease through prohibition of smoking and control of behavior pattern. The subjects consisted of 120 smokers and 90 nonsmokers who were married men older than 30 years working in officers. The officers were surveyed by means of questionnaire September 26 through October 6, 1989. The Instruments used for this study was a self-administered measurement tool composed of 59 items was made through modifications of Jenkuns Activity Survey (JAS). The Data were analysed by SAS (Statistical Analysis System) program personal computer. The statistical technique used for this study were Frequency, chi 2-test, t-test, ANOVA, Pearson Correlation Coefficient. The 15 items were chosen with items above 0.3 of the factor loading in the factor analysis. In the first factor analysis 19 factors were extracted and accounted for 86% of the total variance. However when the number of factors were limited to 3 in order to derive Jenkins classification, three factors were derived. There names are Job-Involvement, Speed & Impatience, Hard-Driving. Each of them includes 21 items, 21 and 9, respectively. The results of this study were as follow: 1. The score of the smoker group and non-smoker group in Job-Involvement (t = 5.7147, p less than 0.0001), Speed & Impatience (t = 4.6756, p less than .0001), Hard-Driving (t = 8.0822, p less than .0001) and total type A behavior pattern showed statistically significant differences (t = 8.1224, p less than .0001). 2. The score of type A behavior pattern by number of cigarettes smoked daily were not statistically significant differences. 3. The score of type A behavior pattern by duration of smoking were not significant differences. It was concluded that the relationship between smokers and non-smokers of type A behavior pattern was statistically significant difference but number of cigarettes smoked daily and duration of smoking were not significant differences. Therefore this study is needed to adequate nursing intervention of type A behavior pattern in order to elevated to educational effect for prohibition of cigarette smoking.

Role of optimization criterion in static asymmetric analysis of lumbar spine load.

PubMed

Daniel, Matej

2011-10-01

A common method for load estimation in biomechanics is the inverse dynamics optimization, where the muscle activation pattern is found by minimizing or maximizing the optimization criterion. It has been shown that various optimization criteria predict remarkably similar muscle activation pattern and intra-articular contact forces during leg motion. The aim of this paper is to study the effect of the choice of optimization criterion on L4/L5 loading during static asymmetric loading. Upright standing with weight in one stretched arm was taken as a representative position. Musculoskeletal model of lumbar spine model was created from CT images of Visible Human Project. Several criteria were tested based on the minimization of muscle forces, muscle stresses, and spinal load. All criteria provide the same level of lumbar spine loading (difference is below 25%), except the criterion of minimum lumbar shear force which predicts unrealistically high spinal load and should not be considered further. Estimated spinal load and predicted muscle force activation pattern are in accordance with the intradiscal pressure measurements and EMG measurements. The L4/L5 spine loads 1312 N, 1674 N, and 1993 N were predicted for mass of weight in hand 2, 5, and 8 kg, respectively using criterion of mininum muscle stress cubed. As the optimization criteria do not considerably affect the spinal load, their choice is not critical in further clinical or ergonomic studies and computationally simpler criterion can be used.

Short term load forecasting of anomalous load using hybrid soft computing methods

NASA Astrophysics Data System (ADS)

Rasyid, S. A.; Abdullah, A. G.; Mulyadi, Y.

2016-04-01

Load forecast accuracy will have an impact on the generation cost is more economical. The use of electrical energy by consumers on holiday, show the tendency of the load patterns are not identical, it is different from the pattern of the load on a normal day. It is then defined as a anomalous load. In this paper, the method of hybrid ANN-Particle Swarm proposed to improve the accuracy of anomalous load forecasting that often occur on holidays. The proposed methodology has been used to forecast the half-hourly electricity demand for power systems in the Indonesia National Electricity Market in West Java region. Experiments were conducted by testing various of learning rate and learning data input. Performance of this methodology will be validated with real data from the national of electricity company. The result of observations show that the proposed formula is very effective to short-term load forecasting in the case of anomalous load. Hybrid ANN-Swarm Particle relatively simple and easy as a analysis tool by engineers.

Coherent manipulation of spin correlations in the Hubbard model

NASA Astrophysics Data System (ADS)

Wurz, N.; Chan, C. F.; Gall, M.; Drewes, J. H.; Cocchi, E.; Miller, L. A.; Pertot, D.; Brennecke, F.; Köhl, M.

2018-05-01

We coherently manipulate spin correlations in a two-component atomic Fermi gas loaded into an optical lattice using spatially and time-resolved Ramsey spectroscopy combined with high-resolution in situ imaging. This technique allows us not only to imprint spin patterns but also to probe the static magnetic structure factor at an arbitrary wave vector, in particular, the staggered structure factor. From a measurement along the diagonal of the first Brillouin zone of the optical lattice, we determine the magnetic correlation length and the individual spatial spin correlators. At half filling, the staggered magnetic structure factor serves as a sensitive thermometer, which we employ to study the equilibration in the spin and density sector during a slow quench of the lattice depth.

14 CFR 23.341 - Gust loads factors.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Gust loads factors. 23.341 Section 23.341... loads factors. (a) Each airplane must be designed to withstand loads on each lifting surface resulting... criteria of § 23.333(c). (c) In the absence of a more rational analysis, the gust load factors must be...

Frequency Distribution in Domestic Microwave Ovens and Its Influence on Heating Pattern.

PubMed

Luan, Donglei; Wang, Yifen; Tang, Juming; Jain, Deepali

2017-02-01

In this study, snapshots of operating frequency profiles of domestic microwave ovens were collected to reveal the extent of microwave frequency variations under different operation conditions. A computer simulation model was developed based on the finite difference time domain method to analyze the influence of the shifting frequency on heating patterns of foods in a microwave oven. The results showed that the operating frequencies of empty and loaded domestic microwave ovens varied widely even among ovens of the same model purchased on the same date. Each microwave oven had its unique characteristic operating frequencies, which were also affected by the location and shape of the load. The simulated heating patterns of a gellan gel model food when heated on a rotary plate agreed well with the experimental results, which supported the reliability of the developed simulation model. Simulation indicated that the heating patterns of a stationary model food load changed with the varying operating frequency. However, the heating pattern of a rotary model food load was not sensitive to microwave frequencies due to the severe edge heating overshadowing the effects of the frequency variations. © 2016 Institute of Food Technologists®.

Assessing Footwear Effects from Principal Features of Plantar Loading during Running.

PubMed

Trudeau, Matthieu B; von Tscharner, Vinzenz; Vienneau, Jordyn; Hoerzer, Stefan; Nigg, Benno M

2015-09-01

The effects of footwear on the musculoskeletal system are commonly assessed by interpreting the resultant force at the foot during the stance phase of running. However, this approach overlooks loading patterns across the entire foot. An alternative technique for assessing foot loading across different footwear conditions is possible using comprehensive analysis tools that extract different foot loading features, thus enhancing the functional interpretation of the differences across different interventions. The purpose of this article was to use pattern recognition techniques to develop and use a novel comprehensive method for assessing the effects of different footwear interventions on plantar loading. A principal component analysis was used to extract different loading features from the stance phase of running, and a support vector machine (SVM) was used to determine whether and how these loading features were different across three shoe conditions. The results revealed distinct loading features at the foot during the stance phase of running. The loading features determined from the principal component analysis allowed successful classification of all three shoe conditions using the SVM. Several differences were found in the location and timing of the loading across each pairwise shoe comparison using the output from the SVM. The analysis approach proposed can successfully be used to compare different loading patterns with a much greater resolution than has been reported previously. This study has several important applications. One such application is that it would not be relevant for a user to select a shoe or for a manufacturer to alter a shoe's construction if the classification across shoe conditions would not have been significant.

Clinical and virological characteristics of 15 patients with chronic active Epstein-Barr virus infection treated with hematopoietic stem cell transplantation.

PubMed

Gotoh, Kensei; Ito, Yoshinori; Shibata-Watanabe, Yukiko; Kawada, Jun-ichi; Takahashi, Yoshiyuki; Yagasaki, Hiroshi; Kojima, Seiji; Nishiyama, Yukihiro; Kimura, Hiroshi

2008-05-15

Chronic active Epstein-Barr virus (EBV) infection is characterized by recurrent infectious mononucleosis-like symptoms, and infected patients have high viral loads in their peripheral blood. Standard therapy for the disease has not yet been established. Recently, hematopoietic stem cell transplantation (HSCT) has been introduced and has the potential to become a standard treatment, although guidelines for HSCT to treat chronic active EBV infection have not yet been proposed. Fifteen patients were retrospectively analyzed, both clinically and virologically, to investigate the factors associated with prognosis of chronic active EBV infection treated with HSCT. After HSCT, 7 patients died after survival periods that ranged from 1 to 16 months (mean duration of survival after HSCT, 5 months). Three patients were considered to have died of transplantation-related complications. The duration between infection onset and diagnosis was significantly longer in patients who died than in those who survived. Five of the 7 patients who died experienced > or =3 life-threatening complications. The plasma concentrations of interferon-gamma, interleukin-10, thrombomodulin, and soluble E-selectin did not differ significantly between the groups of patients. With regard to sequence variations in the EBV latent membrane protein 1 gene, no specific patterns were found in the patients who died. Importantly, the plasma EBV load at diagnosis was significantly higher in patients who died than in living patients. Moreover, plasma viral load was shown to be an important factor to monitor during follow-up for patients after HSCT. The number of life-threatening complications and plasma viral load are indicative of the stage of disease progression and may be useful factors for predicting the outcome of HSCT.

Frequency effects on the stability of a journal bearing for periodic loading

NASA Technical Reports Server (NTRS)

Vijayaraghavan, D.; Brewe, D. E.

1991-01-01

The stability of a journal bearing is numerically predicted when a unidirectional periodic external load is applied. The analysis is performed using a cavitation algorithm, which mimics the Jakobsson-Floberg and Olsson (JFO) theory by accounting for the mass balance through the complete bearing. Hence, the history of the film is taken into consideration. The loading pattern is taken to be sinusoidal and the frequency of the load cycle is varied. The results are compared with the predictions using Reynolds boundary conditions for both film rupture and reformation. With such comparisons, the need for accurately predicting the cavitation regions for complex loading patterns is clearly demonstrated. For a particular frequency of loading, the effects of mass, amplitude of load variation and frequency of journal speed are also investigated. The journal trajectories, transient variations in fluid film forces, net surface velocity and minimum film thickness, and pressure profiles are also presented.

Calibration of LRFR live load factors using weigh-in-motion data.

DOT National Transportation Integrated Search

2006-06-01

The Load and Resistance Factor Rating (LRFR) code for load rating bridges is based on factors calibrated from structural : load and resistance statistics to achieve a more uniform level of reliability for all bridges. The liveload factors in the : LR...

Short-term Natural History of High-Risk Human Papillomavirus Infection in Mid-Adult Women Sampled Monthly (Short title: Short-term HPV Natural History in Mid-Adult Women)

PubMed Central

Fu, Tsung-chieh (Jane); Xi, Long Fu; Hulbert, Ayaka; Hughes, James P.; Feng, Qinghua; Schwartz, Stephen M.; Hawes, Stephen E.; Koutsky, Laura A.; Winer, Rachel L.

2015-01-01

Characterizing short-term HPV detection patterns and viral load may inform HPV natural history in mid-adult women. From 2011–2012, we recruited women aged 30–50 years. Women submitted monthly self-collected vaginal samples for high-risk HPV DNA testing for 6 months. Positive samples were tested for type-specific HPV DNA load by real-time PCR. HPV type-adjusted linear and Poisson regression assessed factors associated with 1) viral load at initial HPV detection and 2) repeat type-specific HPV detection. One-hundred thirty-nine women (36% of 387 women with ≥4 samples) contributed 243 type-specific HR HPV infections during the study; 54% of infections were prevalent and 46% were incident. Incident (versus prevalent) detection and past pregnancy were associated with lower viral load, whereas current smoking was associated with higher viral load. In multivariate analysis, current smoking was associated with a 40% (95%CI:5%–87%) increase in the proportion of samples that were repeatedly positive for the same HPV type, whereas incident (versus prevalent) detection status and past pregnancy were each associated with a reduction in the proportion of samples repeatedly positive (55%,95%CI:38%–67% and 26%,95%CI:10%–39%, respectively). In a separate multivariate model, each log10 increase in viral load was associated with a 10% (95%CI:4%–16%) increase in the proportion of samples repeatedly positive. Factors associated with repeat HPV detection were similar to those observed in longer-term studies, suggesting that short-term repeat detection may relate to long-term persistence. The negative associations between incident HPV detection and both viral load and repeat detection suggest that reactivation or intermittent persistence was more common than new acquisition. PMID:25976733

Nonlinear Buckling Analysis of Functionally Graded Graphene Reinforced Composite Shallow Arches with Elastic Rotational Constraints under Uniform Radial Load.

PubMed

Huang, Yonghui; Yang, Zhicheng; Liu, Airong; Fu, Jiyang

2018-05-28

The buckling behavior of functionally graded graphene platelet-reinforced composite (FG-GPLRC) shallow arches with elastic rotational constraints under uniform radial load is investigated in this paper. The nonlinear equilibrium equation of the FG-GPLRC shallow arch with elastic rotational constraints under uniform radial load is established using the Halpin-Tsai micromechanics model and the principle of virtual work, from which the critical buckling load of FG-GPLRC shallow arches with elastic rotational constraints can be obtained. This paper gives special attention to the effect of the GPL distribution pattern, weight fraction, geometric parameters, and the constraint stiffness on the buckling load. The numerical results show that all of the FG-GPLRC shallow arches with elastic rotational constraints have a higher buckling load-carrying capacity compared to the pure epoxy arch, and arches of the distribution pattern X have the highest buckling load among four distribution patterns. When the GPL weight fraction is constant, the thinner and larger GPL can provide the better reinforcing effect to the FG-GPLRC shallow arch. However, when the value of the aspect ratio is greater than 4, the flakiness ratio is greater than 103, and the effect of GPL's dimensions on the buckling load of the FG-GPLRC shallow arch is less significant. In addition, the buckling model of FG-GPLRC shallow arch with elastic rotational constraints is changed as the GPL distribution patterns or the constraint stiffness changes. It is expected that the method and the results that are presented in this paper will be useful as a reference for the stability design of this type of arch in the future.

Recognizing speech under a processing load: dissociating energetic from informational factors.

PubMed

Mattys, Sven L; Brooks, Joanna; Cooke, Martin

2009-11-01

Effects of perceptual and cognitive loads on spoken-word recognition have so far largely escaped investigation. This study lays the foundations of a psycholinguistic approach to speech recognition in adverse conditions that draws upon the distinction between energetic masking, i.e., listening environments leading to signal degradation, and informational masking, i.e., listening environments leading to depletion of higher-order, domain-general processing resources, independent of signal degradation. We show that severe energetic masking, such as that produced by background speech or noise, curtails reliance on lexical-semantic knowledge and increases relative reliance on salient acoustic detail. In contrast, informational masking, induced by a resource-depleting competing task (divided attention or a memory load), results in the opposite pattern. Based on this clear dissociation, we propose a model of speech recognition that addresses not only the mapping between sensory input and lexical representations, as traditionally advocated, but also the way in which this mapping interfaces with general cognition and non-linguistic processes.

Exploring the impact of network tariffs on household electricity expenditures using load profiles and socio-economic characteristics

NASA Astrophysics Data System (ADS)

Azarova, Valeriya; Engel, Dominik; Ferner, Cornelia; Kollmann, Andrea; Reichl, Johannes

2018-04-01

Growing self-generation and storage are expected to cause significant changes in residential electricity utilization patterns. Commonly applied volumetric network tariffs may induce imbalance between different groups of households and their respective contribution to recovering the operating costs of the grid. Understanding consumer behaviour and appliance usage together with socio-economic factors can help regulatory authorities to adapt network tariffs to new circumstances in a fair way. Here, we assess the effects of 11 network tariff scenarios on household budgets using real load profiles from 765 households. Thus we explore the possibly disruptive impact of applying peak-load-based tariffs on the budgets of households when they have been mainly charged for consumed volumes before. Our analysis estimates the change in household network expenditure for different combinations of energy, peak and fixed charges, and can help to design tariffs that recover the costs needed for the sustainable operation of the grid.

Dietary patterns and the risk of rhinitis in primary school children: a prospective cohort study

PubMed Central

Liu, Xudong; Wong, Claudie Chiu-Yi; Yu, Ignatius T. S.; Zhang, Zilong; Tan, Lixing; Lau, Arthur P. S.; Lee, Albert; Yeoh, Eng Kiong; Lao, Xiang Qian

2017-01-01

This study was to investigate the association between dietary patterns and rhinitis in primary school children. 1,599 students without rhinitis at baseline survey were selected from a primary school children cohort. Information on food consumption, respiratory symptoms, and confounders was collected using questionnaires. Dietary patterns were defined using principal component analysis. Logistic regression was performed to calculate odds ratio (OR) with 95% confidence intervals (95% CI). The incidence of rhinitis during 12 months follow-up was 21.2%. Three patterns were extracted and labeled as pattern I, II and III. Dietary pattern II which had higher factor loadings of legumes, butter, nuts and potatoes was associated with an increased risk of rhinitis (OR: 1.34, 95% CI: 1.01–1.87) when the highest tertile of pattern score was compared to the lowest tertile, after adjusted for confounders. Besides, every 1-unit increase of score of pattern II was also associated with an increased risk of rhinitis (OR: 1.19, 95% CI: 1.05–1.35). Neither pattern I nor Pattern III was observed to be associated with risk of rhinitis. A diet with higher levels of consumption of legumes, butter, nuts and potatoes may increase the risk of allergic rhinitis in primary school children. PMID:28294150

Measuring adolescent science motivation

NASA Astrophysics Data System (ADS)

Schumm, Maximiliane F.; Bogner, Franz X.

2016-02-01

To monitor science motivation, 232 tenth graders of the college preparatory level ('Gymnasium') completed the Science Motivation Questionnaire II (SMQ-II). Additionally, personality data were collected using a 10-item version of the Big Five Inventory. A subsequent exploratory factor analysis based on the eigenvalue-greater-than-one criterion, extracted a loading pattern, which in principle, followed the SMQ-II frame. Two items were dropped due to inappropriate loadings. The remaining SMQ-II seems to provide a consistent scale matching the findings in literature. Nevertheless, also possible shortcomings of the scale are discussed. Data showed a higher perceived self-determination in girls which seems compensated by their lower self-efficacy beliefs leading to equality of females and males in overall science motivation scores. Additionally, the Big Five personality traits and science motivation components show little relationship.

14 CFR 25.1531 - Maneuvering flight load factors.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Maneuvering flight load factors. 25.1531 Section 25.1531 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Operating Limitations § 25.1531 Maneuvering flight load factors. Load factor limitations, not exceeding the...

14 CFR 25.1531 - Maneuvering flight load factors.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Maneuvering flight load factors. 25.1531 Section 25.1531 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Operating Limitations § 25.1531 Maneuvering flight load factors. Load factor limitations, not exceeding the...

Development of an epiphyte indicator of nutrient enrichment. A ...

EPA Pesticide Factsheets

An extensive review of the literature on epiphytes on submerged aquatic vegetation (SAV), primarily seagrasses but including some brackish and freshwater rooted macrophytes, was conducted in order to evaluate the evidence for response of epiphyte metrics to increased nutrients. Evidence from field observational studies together with laboratory and field mesocosm experiments was assembled from the literature and evaluated for evidence of a hypothesized positive response to nutrient addition. There was general consistency in the results to confirm that elevated nutrients tended to increase the load of epiphytes on the surface of SAV, in the absence of other limiting factors. In spite of multiple sources of uncontrolled variation, positive relationships of epiphyte load to nutrient concentration or load (either N or P) were often observed along strong anthropogenic or natural nutrient gradients in coastal regions, although response patterns may only be evident for parts of the year. Mesocosm nutrient studies tended to be more common for temperate regions and field addition studies more common for tropical and subtropical regions. Addition of nutrients via the water column tended to elicit stronger epiphyte responses than sediment additions, and may be a factor in the lack of epiphyte response reported in some studies. Mesograzer activity is a critical covariate for epiphyte response under experimental nutrient elevation, but the epiphyte response is highly de

Estimation of particulate nutrient load using turbidity meter.

PubMed

Yamamoto, K; Suetsugi, T

2006-01-01

The "Nutrient Load Hysteresis Coefficient" was proposed to evaluate the hysteresis of the nutrient loads to flow rate quantitatively. This could classify the runoff patterns of nutrient load into 15 patterns. Linear relationships between the turbidity and the concentrations of particulate nutrients were observed. It was clarified that the linearity was caused by the influence of the particle size on turbidity output and accumulation of nutrients on smaller particles (diameter < 23 microm). The L-Q-Turb method, which is a new method for the estimation of runoff loads of nutrients using a regression curve between the turbidity and the concentrations of particulate nutrients, was developed. This method could raise the precision of the estimation of nutrient loads even if they had strong hysteresis to flow rate. For example, as for the runoff load of total phosphorus load on flood events in a total of eight cases, the averaged error of estimation of total phosphorus load by the L-Q-Turb method was 11%, whereas the averaged estimation error by the regression curve between flow rate and nutrient load was 28%.

Heterogeneity in fire severity within early season and late season prescribed burns in a mixed-conifer forest

USGS Publications Warehouse

Knapp, E.E.; Keeley, J.E.

2006-01-01

Structural heterogeneity in forests of the Sierra Nevada was historically produced through variation in fire regimes and local environmental factors. The amount of heterogeneity that prescription burning can achieve might now be more limited owing to high fuel loads and increased fuel continuity. Topography, woody fuel loading, and vegetative composition were quantified in plots within replicated early and late season burn units. Two indices of fire severity were evaluated in the same plots after the burns. Scorch height ranged from 2.8 to 25.4 m in early season plots and 3.1 to 38.5 m in late season plots, whereas percentage of ground surface burned ranged from 24 to 96% in early season plots and from 47 to 100% in late season plots. Scorch height was greatest in areas with steeper slopes, higher basal area of live trees, high percentage of basal area composed of pine, and more small woody fuel. Percentage of area burned was greatest in areas with less bare ground and rock cover (more fuel continuity), steeper slopes, and units burned in the fall (lower fuel moisture). Thus topographic and biotic factors still contribute to the abundant heterogeneity in fire severity with prescribed burning, even under the current high fuel loading conditions. Burning areas with high fuel loads in early season when fuels are moister may lead to patterns of heterogeneity in fire effects that more closely approximate the expected patchiness of historical fires.

Combining chemometric tools for assessing hazard sources and factors acting simultaneously in contaminated areas. Case study: "Mar Piccolo" Taranto (South Italy).

PubMed

Mali, Matilda; Dell'Anna, Maria Michela; Notarnicola, Michele; Damiani, Leonardo; Mastrorilli, Piero

2017-10-01

Almost all marine coastal ecosystems possess complex structural and dynamic characteristics, which are influenced by anthropogenic causes and natural processes as well. Revealing the impact of sources and factors controlling the spatial distributions of contaminants within highly polluted areas is a fundamental propaedeutic step of their quality evaluation. Combination of different pattern recognition techniques, applied to one of the most polluted Mediterranean coastal basin, resulted in a more reliable hazard assessment. PCA/CA and factorial ANOVA were exploited as complementary techniques for apprehending the impact of multi-sources and multi-factors acting simultaneously and leading to similarities or differences in the spatial contamination pattern. The combination of PCA/CA and factorial ANOVA allowed, on one hand to determine the main processes and factors controlling the contamination trend within different layers and different basins, and, on the other hand, to ascertain possible synergistic effects. This approach showed the significance of a spatially representative overview given by the combination of PCA-CA/ANOVA in inferring the historical anthropogenic sources loading on the area. Copyright © 2017 Elsevier Ltd. All rights reserved.

Load estimation from photoelastic fringe patterns under combined normal and shear forces

NASA Astrophysics Data System (ADS)

Dubey, V. N.; Grewal, G. S.

2009-08-01

Recently there has been some spurt of interests to use photoelastic materials for sensing applications. This has been successfully applied for designing a number of signal-based sensors, however, there have been limited efforts to design image-based sensors on photoelasticity which can have wider applications in term of actual loading and visualisation. The main difficulty in achieving this is the infinite loading conditions that may generate same image on the material surface. This, however, can be useful for known loading situations as this can provide dynamic and actual conditions of loading in real time. This is particularly useful for separating components of forces in and out of the loading plane. One such application is the separation of normal and shear forces acting on the plantar surface of foot of diabetic patients for predicting ulceration. In our earlier work we have used neural networks to extract normal force information from the fringe patterns using image intensity. This paper considers geometric and various other statistical parameters in addition to the image intensity to extract normal as well as shear force information from the fringe pattern in a controlled experimental environment. The results of neural network output with the above parameters and their combinations are compared and discussed. The aim is to generalise the technique for a range of loading conditions that can be exploited for whole-field load visualisation and sensing applications in biomedical field.

Environmental Effects on Long Term Displacement Data of Woven Fabric Webbings Under Constant Load for Inflatable Structures

NASA Technical Reports Server (NTRS)

Kenner, WInfred S.; Jones, Thomas C.; Doggett, William R.; Duncan, Quinton; Plant, James

2015-01-01

An experimental study of the effects of environmental temperature and humidity conditions on long-term creep displacement data of high strength Kevlar and VectranTM woven fabric webbings under constant load for inflatable structures is presented. The restraint layer of an inflatable structure for long-duration space exploration missions is designed to bear load and consists of an assembly of high strength webbings. Long-term creep displacement data of webbings can be utilized by designers to validate service life parameters of restraint layers of inflatable structures. Five groups of high-strength webbings were researched over a two year period. Each group had a unique webbing length, load rating, applied load, and test period. The five groups consisted of 1.) 6K Vectran webbings loaded to 49% ultimate tensile strength (UTS), 2.) 6K Vectran webbings loaded to 55% UTS, 3.) 12.5K Vectran webbings loaded to 22% UTS, 4.) 6K Kevlar webbings loaded to 40% and 43% UTS, and 5.) 6K Kevlar webbings loaded to 48% UTS. Results show that all webbing groups exhibit the initial two stages of three of a typical creep curve of an elastic material. Results also show that webbings exhibit unique local wave patterns over the duration of the test period. Data indicate that the local pattern is primarily generated by daily variations in relative humidity values within the test facility. Data indicate that after a three to six month period, where webbings reach a steady-state creep condition, an annual sinusoidal displacement pattern is exhibited, primarily due to variations in annual mean temperature values. Data indicates that variations in daily temperature values and annual mean humidity values have limited secondary effects on creep displacement behavior. Results show that webbings in groups 2 and 5 do not exhibit well defined annual displacement patterns because the magnitude of the applied loads cause large deformations, and data indicate that material yielding within a webbing tends to neutralize the annual sinusoidal displacement pattern. Study indicates that applied load, environmental effects, mechanical strength, coefficient of thermal expansion, and hygroscopic properties of webbings are fundamental requirements for quantifying accurate creep displacements and behaviors over multiple year time periods. Results from a study of the environmental effects on long-term creep displacement data of Kevlar and Vectran woven webbings are presented to increase the knowledge base of webbing materials and to enhance designs of inflatable space structures for long-duration space missions.

Standing Height as a Prevention Measure for Overuse Injuries of the Back in Alpine Ski Racing: A Kinematic and Kinetic Study of Giant Slalom

PubMed Central

Spörri, Jörg; Kröll, Josef; Fasel, Benedikt; Aminian, Kamiar; Müller, Erich

2018-01-01

Background: In alpine ski racing, typical loading patterns of the back include a combined occurrence of spinal bending, torsion, and high peak loads. These factors are known to be associated with high spinal disc loading and have been suggested to be attributable to different types of spine deterioration. However, little is known about the effect of standing height (ie, the distance between the bottom of the running surface of the ski and the ski boot sole) on the aforementioned back loading patterns. Purpose: To investigate the effect of reduced standing height on the skier’s overall trunk kinematics and the acting ground-reaction forces in giant slalom (GS) from an overuse injury prevention perspective. Study Design: Controlled laboratory study. Methods: Seven European Cup–level athletes skied a total of 224 GS turns with 2 different pairs of skis varying in standing height. Their overall trunk movement (frontal bending, lateral bending, and torsion angles) was measured based on 2 inertial measurement units located at the sacrum and sternum. Pressure insoles were used to determine the total ground-reaction force. Results: During the turn phase in which the greatest spinal disc loading is expected to occur, significantly lower total ground-reaction forces were observed for skis with a decreased standing height. Simultaneously, the skier’s overall trunk movement (ie, frontal bending, lateral bending, and torsion angles) remained unwaveringly high. Conclusion: Standing height is a reasonable measure to reduce the skier’s overall back loading in GS. Yet, when compared with the effects achievable by increased gate offsets in slalom, for instance, the preventative benefits of decreased standing height seem to be rather small. Clinical Relevance: To reduce the magnitude of overall back loading in GS and to prevent overuse injuries of the back, decreasing standing height might be an efficient approach. Nevertheless, the clinical relevance of the current findings, as well as the effectiveness of the measure “reduced standing height,” must be verified by epidemiological studies before its preventative potential can be judged as conclusive. PMID:29344540

Footwear Matters: Influence of Footwear and Foot Strike on Load Rates during Running.

PubMed

Rice, Hannah M; Jamison, Steve T; Davis, Irene S

2016-12-01

Running with a forefoot strike (FFS) pattern has been suggested to reduce the risk of overuse running injuries, due to a reduced vertical load rate compared with rearfoot strike (RFS) running. However, resultant load rate has been reported to be similar between foot strikes when running in traditional shoes, leading to questions regarding the value of running with a FFS. The influence of minimal footwear on the resultant load rate has not been considered. This study aimed to compare component and resultant instantaneous loading rate (ILR) between runners with different foot strike patterns in their habitual footwear conditions. Twenty-nine injury-free participants (22 men, seven women) ran at 3.13 m·s along a 30-m runway, with their habitual foot strike and footwear condition. Ground reaction force data were collected. Peak ILR values were compared between three conditions; those who habitually run with an RFS in standard shoes, with an FFS in standard shoes, and with an FFS in minimal shoes. Peak resultant, vertical, lateral, and medial ILR were lower (P < 0.001) when running in minimal shoes with an FFS than in standard shoes with either foot strike. When running with an FFS, peak posterior ILR were lower (P < 0.001) in minimal than standard shoes. When running in a standard shoe, peak resultant and component ILR were similar between footstrike patterns. However, load rates were lower when running in minimal shoes with a FFS, compared with running in standard shoes with either foot strike. Therefore, it appears that footwear alters the load rates during running, even with similar foot strike patterns.

Borderline personality disorder traits and their relationship with dimensions of normative personality: a web-based cohort and twin study

PubMed Central

Kendler, K. S.; Myers, J.; Reichborn-Kjennerud, T.

2011-01-01

Objective To describe the structure of genetic and environmental risk factors for four dimensions of borderline personality disorder (BPD) and to understand the source of resemblance of these dimensions and normal personality. Method A web-based sample (n = 44,112 including 542 twin pairs) completed items from 4 scales of the Dimensional Assessment of Personality Pathology Basic Questionnaire and the Big Five Inventory. Results A one-factor common pathway model best fits the 4 BPD scales producing a highly heritable latent liability (heritability = 60%) and strong loadings on all 4 dimensions. Affective instability had the lowest trait-specific genetic loading, suggesting that it was a core feature of BPD. A complex pattern of genetic and environmental associations was found between the big five personality traits and BPD dimensions. The strongest genetic correlations with the BPD traits were generally seen for neuroticism (positive), followed by conscientiousness and agreeableness, both negative. Conclusion In the general population, these four BPD dimensions reflect one underlying highly heritable factor. The association between normative personality and dimensions of BPD is complex with high degrees of genetic correlation. PMID:21198457

Borderline personality disorder traits and their relationship with dimensions of normative personality: a web-based cohort and twin study.

PubMed

Kendler, K S; Myers, J; Reichborn-Kjennerud, T

2011-05-01

To describe the structure of genetic and environmental risk factors for four dimensions of borderline personality disorder (BPD) and to understand the source of resemblance of these dimensions and normal personality. A web-based sample (n = 44,112 including 542 twin pairs) completed items from 4 scales of the Dimensional Assessment of Personality Pathology Basic Questionnaire and the Big Five Inventory. A one-factor common pathway model best fits the 4 BPD scales producing a highly heritable latent liability (heritability = 60%) and strong loadings on all 4 dimensions. Affective instability had the lowest trait-specific genetic loading, suggesting that it was a core feature of BPD. A complex pattern of genetic and environmental associations was found between the big five personality traits and BPD dimensions. The strongest genetic correlations with the BPD traits were generally seen for neuroticism (positive), followed by conscientiousness and agreeableness, both negative. In the general population, these four BPD dimensions reflect one underlying highly heritable factor. The association between normative personality and dimensions of BPD is complex with high degrees of genetic correlation. © 2010 John Wiley & Sons A/S.

Major Maternal Dietary Patterns during Early Pregnancy and Their Association with Neonatal Anthropometric Measurement

PubMed Central

Hajianfar, Hossein; Esmaillzadeh, Ahmad; Feizi, Awat; Shahshahan, Zahra

2018-01-01

Background Anthropometric measurements of newborn infant are widely assessed as determinants of maternal nutrition. Although earlier studies have mostly examined the effects of particular nutrients or foods during gestational period on neonatal anthropometric measurements, there are few studies regarding the association of dietary patterns and mentioned measurements. So, the purpose of the current study was to investigate the association between major maternal dietary patterns and neonatal anthropometric measurements including body weight, head circumference, and height. Methods The current prospective observational study is based on the data collected from 812 pregnant women. Dietary data was collected using a validated semiquantitative food frequency questionnaire. Results Three identified major dietary patterns according to the results obtained from the factor loading matrix were (i) “western dietary pattern”; (ii) “traditional dietary pattern”; (iii) “healthy dietary pattern”. Overall, this study demonstrated a positive significant association between high adherences to western dietary pattern and chance of having low birth weight infant. However, such associations were not seen in women taking healthy and traditional dietary patterns. Conclusion We found that healthier maternal dietary patterns during early pregnancy might be associated with lower risk of low birth weight. Further studies are required to confirm these findings.

Meal frequency patterns and glycemic properties of maternal diet in relation to preterm delivery: Results from a large prospective cohort study

PubMed Central

Birgisdottir, Bryndis Eva; Sengpiel, Verena; Brantsæter, Anne Lise; Haugen, Margareta; Myhre, Ronny; Meltzer, Helle Margrete; Jacobsson, Bo

2017-01-01

Background Dietary habits are linked to high maternal glucose levels, associated with preterm delivery. The aim of this study was to examine the associations between meal frequency and glycemic properties of maternal diet in relation to preterm delivery. Methods This prospective cohort study included 66,000 women from the Norwegian Mother and Child Cohort Study (MoBa). Meal frequency and food intake data were obtained from a validated food frequency questionnaire during mid-pregnancy. Principal component factor analysis was used with a data-driven approach, and three meal frequency patterns were identified: “snack meal”, “main meal”, and “evening meal”. Pattern scores were ranked in quartiles. Glycemic index and glycemic load were estimated from table values. Intakes of carbohydrates, added sugar, and fiber were reported in grams per day and divided into quartiles. Gestational age was obtained from the Medical Birth Registry of Norway. Preterm delivery was defined as birth at <37 gestational weeks. A Cox regression model was used to assess associations with preterm delivery. Results After adjustments, the “main meal” pattern was associated with a reduced risk of preterm delivery, with hazard ratios (HRs) of 0.89 (95% confidence interval (CI): 0.80, 0.98) and 0.90 (95% CI: 0.81, 0.99) for the third and fourth quartiles, respectively, and p for trend of 0.028. This was mainly attributed to the group of women with BMI ≥25 kg/m2, with HRs of 0.87 (95% CI: 0.79, 0.96) and 0.89 (95% CI: 0.80, 0.98) for the third and fourth quartiles, respectively, and p for trend of 0.010. There was no association between glycemic index, glycemic load, carbohydrates, added sugar, fiber, or the remaining meal frequency patterns and preterm delivery. Conclusion Regular consumption of main meals (breakfast, lunch, dinner) was associated with a lower risk of preterm delivery. Diet should be further studied as potential contributing factors for preterm delivery. PMID:28249018

The effects of a deleterious mutation load on patterns of influenza A/H3N2's antigenic evolution in humans

PubMed Central

Koelle, Katia; Rasmussen, David A

2015-01-01

Recent phylogenetic analyses indicate that RNA virus populations carry a significant deleterious mutation load. This mutation load has the potential to shape patterns of adaptive evolution via genetic linkage to beneficial mutations. Here, we examine the effect of deleterious mutations on patterns of influenza A subtype H3N2's antigenic evolution in humans. By first analyzing simple models of influenza that incorporate a mutation load, we show that deleterious mutations, as expected, act to slow the virus's rate of antigenic evolution, while making it more punctuated in nature. These models further predict three distinct molecular pathways by which antigenic cluster transitions occur, and we find phylogenetic patterns consistent with each of these pathways in influenza virus sequences. Simulations of a more complex phylodynamic model further indicate that antigenic mutations act in concert with deleterious mutations to reproduce influenza's spindly hemagglutinin phylogeny, co-circulation of antigenic variants, and high annual attack rates. DOI: http://dx.doi.org/10.7554/eLife.07361.001 PMID:26371556

The relationship between control, kinematic and electromyographic variables in fast single-joint movements in humans.

PubMed

Feldman, A G; Adamovich, S V; Levin, M F

1995-01-01

Two versions of the hypothesis that discrete movements are produced by shifts in the system's equilibrium point are considered. The first suggests that shifts are monotonic and end near the peak velocity of movement, and the second presumes that they are nonmonotonic ("N-shaped") and proceed until the end of movement. The first version, in contrast to the second, predicts that movement time may be significantly reduced by opposing loads without changes in the control pattern. The purpose of the present study was to test the two hypotheses about the duration and shape of the shift in the equilibrium point based on their respective predictions concerning the effects of perturbations on kinematic and EMG patterns in fast elbow flexor movements. Subjects performed unopposed flexions of about 55-70 degrees (control trials) and, in random test trials, movements were opposed by spring-like loads generated by a torque motor. Subjects had no visual feedback and were instructed not to correct arm deflections in case of perturbations. After the end of the movement, the load was removed leading to a secondary movement to the same final position as that in control trials (equifinality). When the load was varied, the static arm positions before unloading and associated joint torques (ranging from 0 to 80-90% of maximum voluntary contraction) had a monotonic relationship. Test movements opposed by a high load (80-90% of maximal voluntary contraction) ended near the peak velocity of control movements. Phasic and tonic electromyographic patterns were load-dependent. In movements opposed by high loads, the first agonist burst was significantly prolonged and displayed a high level of tonic activity for as long as the load was maintained. In the same load conditions, the antagonist burst was suppressed during the dynamic and static phases of movement. The findings of suppression of the antagonist burst does not support the hypothesis of an N-shaped control signal. Equally, the substantial reduction in movement time by the introduction of an opposing load cannot be reconciled in this model. Instead, our data indicate that the shifts in the equilibrium point underlying fast flexor movements are of short duration, ending near the peak velocity of unopposed movement. This suggests that kinematic and electromyographic patterns represent a long-lasting oscillatory response of the system to the short-duration monotonic control pattern, external forces and proprioceptive feedback.

14 CFR 398.9 - Load factor standards.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Load factor standards. 398.9 Section 398.9... STATEMENTS GUIDELINES FOR INDIVIDUAL DETERMINATIONS OF BASIC ESSENTIAL AIR SERVICE § 398.9 Load factor standards. The load factor standards used in this part may be raised for individual eligible places under...

14 CFR 25.337 - Limit maneuvering load factors.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit maneuvering load factors. 25.337... Conditions § 25.337 Limit maneuvering load factors. (a) Except where limited by maximum (static) lift... maneuvering load factors prescribed in this section. Pitching velocities appropriate to the corresponding pull...

Role of subchondral bone properties and changes in development of load-induced osteoarthritis in mice.

PubMed

Adebayo, O O; Ko, F C; Wan, P T; Goldring, S R; Goldring, M B; Wright, T M; van der Meulen, M C H

2017-12-01

Animal models recapitulating post-traumatic osteoarthritis (OA) suggest that subchondral bone (SCB) properties and remodeling may play major roles in disease initiation and progression. Thus, we investigated the role of SCB properties and its effects on load-induced OA progression by applying a tibial loading model on two distinct mouse strains treated with alendronate (ALN). Cyclic compression was applied to the left tibia of 26-week-old male C57Bl/6 (B6, low bone mass) and FVB (high bone mass) mice. Mice were treated with ALN (26 μg/kg/day) or vehicle (VEH) for loading durations of 1, 2, or 6 weeks. Changes in articular cartilage and subchondral and epiphyseal cancellous bone were analyzed using histology and microcomputed tomography. FVB mice exhibited thicker cartilage, a thicker SCB plate, and higher epiphyseal cancellous bone mass and tissue mineral density than B6 mice. Loading induced cartilage pathology, osteophyte formation, and SCB changes; however, lower initial SCB mass and stiffness in B6 mice did not attenuate load-induced OA severity compared to FVB mice. By contrast, FVB mice exhibited less cartilage damage, and slower-growing and less mature osteophytes. In B6 mice, inhibiting bone remodeling via ALN treatment exacerbated cartilage pathology after 6 weeks of loading, while in FVB mice, inhibiting bone remodeling protected limbs from load-induced cartilage loss. Intrinsically lower SCB properties were not associated with attenuated load-induced cartilage loss. However, inhibiting bone remodeling produced differential patterns of OA pathology in animals with low compared to high SCB properties, indicating that these factors do influence load-induced OA progression. Copyright © 2017 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Determining if Borderline Personality Disorder and Bipolar Disorder Are Alternative Expressions of the Same Disorder: Results From the National Epidemiologic Survey on Alcohol and Related Conditions.

PubMed

de la Rosa, Iris; Oquendo, María A; García, Gemma; Stanley, Barbara; González-Pinto, Ana; Liu, Shang-Min; Blanco, Carlos

To examine whether bipolar disorder and borderline personality disorder represent 2 different disorders or alternative manifestations of the same disorder. The data were collected between January 1, 2004, and December 31, 2005. The analyses were conducted between December 21 and December 27, 2010. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were performed on 25 symptoms assessing depression, mania, and borderline personality disorder from the National Epidemiologic Survey on Alcohol and Related Conditions, a large nationally representative sample of the US adult population (N = 34,653). DSM-IV criteria were used for diagnosis of bipolar disorder and borderline personality disorder. A 3-factor solution provided an excellent fit in both the EFA (root mean square error of approximation [RMSEA] = 0.017, comparative fix index [CFI] = 0.997) and the CFA (RMSEA = 0.024, CFI = 0.993). Factor 1 (Borderline Personality Disorder) loaded on all 9 borderline personality disorder symptoms, factor 2 (Depression) loaded on 8 symptoms of depression, and factor 3 (Mania) loaded on 7 symptoms of mania plus the psychomotor agitation item of the depression section. The correlations between the Borderline Personality Disorder and Depression factors (r = 0.328) and between the Borderline Personality Disorder and Mania factors (r = 0.394) were lower than the correlation between Depression and Mania factors (r = 0.538). A model with 3 positively correlated factors provided an excellent fit for the latent structure of borderline personality disorder and bipolar disorder symptoms. The pattern of pairwise correlations between the 3 factors is consistent with the clinical presentation of 2 syndromes (depression and mania) that can be characterized as a unitary psychiatric entity (bipolar disorder) and a third syndrome (borderline personality disorder) that is often comorbid with bipolar disorder. The findings converge in suggesting that bipolar disorder and borderline personality disorder are overlapping but different pathologies. These findings may serve to inform ongoing efforts to refine the existing psychiatric nosology and to suggest new avenues for etiologic and treatment research. © Copyright 2017 Physicians Postgraduate Press, Inc.

Highly Loaded Mesoporous Silica/Nanoparticle Composites and Patterned Mesoporous Silica Films

NASA Astrophysics Data System (ADS)

Kothari, Rohit; Hendricks, Nicholas R.; Wang, Xinyu; Watkins, James J.

2014-03-01

Novel approaches for the preparation of highly filled mesoporous silica/nanoparticle (MS/NP) composites and for the fabrication of patterned MS films are described. The incorporation of iron platinum NPs within the walls of MS is achieved at high NP loadings by doping amphiphilic poly(ethylene oxide-b-propylene oxide-b-ethylene oxide) (Pluronic®) copolymer templates via selective hydrogen bonding between the pre-synthesized NPs and the hydrophilic portion of the block copolymer. The MS is then synthesized by means of phase selective condensation of tetraethylorthosilicate (TEOS) within the NP loaded block copolymer templates dilated with supercritical carbon dioxide (scCO2) followed by calcination. For patterned films, microphase separated block copolymer/small molecule additive blends are patterned using UV-assisted nanoimprint lithography. Infusion and condensation of a TEOS within template films using ScCO2 as a processing medium followed by calcination yields the patterned MS films. Scanning electron microscopy is used characterize pattern fidelity and transmission electron microscopy analysis confirms the presence of the mesopores. Long range order in nanocomposites is confirmed by low angle x-ray diffraction.

Monosodium Glutamate Intake, Dietary Patterns and Asthma in Chinese Adults

PubMed Central

Shi, Zumin; Yuan, Baojun; Wittert, Gary A.; Pan, Xiaoqun; Dai, Yue; Adams, Robert; Taylor, Anne W.

2012-01-01

Objectives Emerging evidence shows that diet is related to asthma. The aim of this analysis was to investigate the association between monosodium glutamate (MSG) intake, overall dietary patterns and asthma. Methods Data from 1486 Chinese men and women who participated in the Jiangsu Nutrition Study (JIN) were analyzed. In this study, MSG intake and dietary patterns were quantitatively assessed in 2002. Information on asthma history was collected during followed-up in 2007. Results Of the sample, 1.4% reported ever having asthma. MSG intake was not positively associated with asthma. There was a significant positive association between ‘traditional’ (high loadings on rice, wheat flour, and vegetable) food pattern and asthma. No association between ’macho’ (rich in meat and alcohol), ‘sweet tooth’ (high loadings on cake, milk, and yoghurt) ‘vegetable rich’ (high loadings on whole grain, fruit, and vegetable) food patterns and asthma was found. Smoking and overweight were not associated with asthma in the sample. Conclusion While a ‘Traditional’ food pattern was positively associated with asthma among Chinese adults, there was no significant association between MSG intake and asthma. PMID:23240044

Gaze entropy reflects surgical task load.

PubMed

Di Stasi, Leandro L; Diaz-Piedra, Carolina; Rieiro, Héctor; Sánchez Carrión, José M; Martin Berrido, Mercedes; Olivares, Gonzalo; Catena, Andrés

2016-11-01

Task (over-)load imposed on surgeons is a main contributing factor to surgical errors. Recent research has shown that gaze metrics represent a valid and objective index to asses operator task load in non-surgical scenarios. Thus, gaze metrics have the potential to improve workplace safety by providing accurate measurements of task load variations. However, the direct relationship between gaze metrics and surgical task load has not been investigated yet. We studied the effects of surgical task complexity on the gaze metrics of surgical trainees. We recorded the eye movements of 18 surgical residents, using a mobile eye tracker system, during the performance of three high-fidelity virtual simulations of laparoscopic exercises of increasing complexity level: Clip Applying exercise, Cutting Big exercise, and Translocation of Objects exercise. We also measured performance accuracy and subjective rating of complexity. Gaze entropy and velocity linearly increased with increased task complexity: Visual exploration pattern became less stereotyped (i.e., more random) and faster during the more complex exercises. Residents performed better the Clip Applying exercise and the Cutting Big exercise than the Translocation of Objects exercise and their perceived task complexity differed accordingly. Our data show that gaze metrics are a valid and reliable surgical task load index. These findings have potential impacts to improve patient safety by providing accurate measurements of surgeon task (over-)load and might provide future indices to assess residents' learning curves, independently of expensive virtual simulators or time-consuming expert evaluation.

Comparative study on the muscular load of the arms using hair driers.

PubMed

Harada, H; Katsuura, T; Kikuchi, Y

1995-12-01

The purpose of the present study was to evaluate the muscular load of the arm when combing the hair using different "kuru-kuru" type of hair driers. Ten female students (20-24 years old) volunteered as subjects. Five combing patterns were conducted as follows: 1) comb outer layer of right side of hair using right hand, 2) comb outer layer of left side of hair using right hand, 3) comb inner layer of left side of hair using right hand, 4) comb outer layer of back hair using right hand, and 5) comb inner layer of right side of hair using left hand. Surface EMGs were recorded from M. flexor carpi ulnaris, M. brachioradialis, M. biceps brachii, M. triceps brachii, M. deltoideus and M. trapezius of both sides of body. Integrated EMGs (iEMGs) were used to evaluate muscular load for each of the seven different types of hair driers used. The relationship between iEMGs and weight, center of gravity, diameter, length, and circumference of each hair drier were examined. The weight of hair driers tended to be the effective factor on the muscular load. Muscular load also had a tendency to be affected by the shape of the grips. With regard to the hand size, the longer the thumb length, the smaller is the muscular load. It was suggested that a relatively large diameter of the bulb-shaped grip of the drier gave a smaller muscular load among the hair driers examined in the present experiment.

Factor analysis and predictive validity of microcomputer-based tests

NASA Technical Reports Server (NTRS)

Kennedy, R. S.; Baltzley, D. R.; Turnage, J. J.; Jones, M. B.

1989-01-01

11 tests were selected from two microcomputer-based performance test batteries because previously these tests exhibited rapid stability (less than 10 min, of practice) and high retest reliability efficiencies (r greater than 0.707 for each 3 min. of testing). The battery was administered three times to each of 108 college students (48 men and 60 women) and a factor analysis was performed. Two of the three identified factors appear to be related to information processing ("encoding" and "throughput/decoding"), and the third named an "output/speed" factor. The spatial, memory, and verbal tests loaded on the "encoding" factor and included Grammatical Reasoning, Pattern Comparison, Continuous Recall, and Matrix Rotation. The "throughput/decoding" tests included perceptual/numerical tests like Math Processing, Code Substitution, and Pattern Comparison. The output speed factor was identified by Tapping and Reaction Time tests. The Wonderlic Personnel Test was group administered before the first and after the last administration of the performance tests. The multiple Rs in the total sample between combined Wonderlic as a criterion and less than 5 min. of microcomputer testing on Grammatical Reasoning and Math Processing as predictors ranged between 0.41 and 0.52 on the three test administrations. Based on these results, the authors recommend a core battery which, if time permits, would consist of two tests from each factor. Such a battery is now known to permit stable, reliable, and efficient assessment.

The performance of the Edinburgh Postnatal Depression Scale in English speaking and non-English speaking populations in Australia.

PubMed

Small, Rhonda; Lumley, Judith; Yelland, Jane; Brown, Stephanie

2007-01-01

The Edinburgh Postnatal Depression Scale (EPDS) has been widely used to assess maternal depression following childbirth in a range of English speaking countries, and increasingly also in translation in non-English speaking ones. It has performed satisfactorily in most validation studies, has proved easy to administer, is acceptable to women, and rates of depression in the range of 10-20% have been consistently found. The performance of the EPDS was compared across different population samples in Australia: (i) Women born in Australia or in another English speaking country who completed the EPDS in English as part of the 1994 postal Survey of Recent Mothers (SRM) 6-7 months after birth (n = 1166); (ii) Women born in non-English speaking countries who also completed the EPDS in English in the same survey (n = 142); and (iii) Women born in Vietnam (n = 103), Turkey (n = 104) and the Philippines (n = 106) who completed the EPDS 6-9 months after birth in translation in the Mothers in a New Country Study (MINC) study (total n = 313). The pattern of item responses on the EPDS was assessed in various ways across the samples and internal reliability coefficients were calculated. Exploratory factor analyses were also conducted to assess the similarity in the factor solutions across the samples. The EPDS had good construct validity and item endorsement by women was similar across the samples. Internal reliability of the scale was also very satisfactory with Cronbach's alpha for each sample being > or = 8. Between 39 and 46% of the variance in each of the three main samples was accounted for by one principal factor 'depression' (6-7 items loading), with two supplementary factors 'loss of enjoyment' (2 items loading) and 'despair/self-harm' (2-3 items loading) accounting for a further 20-25% of the variance. Alternative one and two factor solutions also showed a great deal of consistency between the samples. The good item consistency of the EPDS and the relative stability of the factor patterns across the samples are indicative that the scale is understood and completed in similar ways by women in these different English speaking and non-English speaking population groups. With the proviso that careful translation processes and extensive piloting of translations are always needed, these findings lend further support to the use of the EPDS in cross-cultural research on depression following childbirth.

The health of Australian veterans of the 1991 Gulf War: factor analysis of self-reported symptoms.

PubMed

Forbes, A B; McKenzie, D P; Mackinnon, A J; Kelsall, H L; McFarlane, A C; Ikin, J F; Glass, D C; Sim, M R

2004-12-01

A recent report showed that Australian veterans of the 1991 Gulf War displayed a greater prevalence of a multitude of self-reported symptoms than a randomly sampled comparison group of military personnel who were eligible for deployment but were not deployed to the Gulf. To investigate whether the pattern, rather than frequency, of symptom reporting in these Australian Gulf War veterans differed from that of the comparison group personnel. Factor analysis was used to determine whether the co-occurrence of 62 symptoms in 1322 male Gulf War veterans can be explained by a number of underlying dimensions, called factors. The methodology was also applied to 1459 male comparison group subjects and the factor solutions of the two groups were compared. For the Gulf War veterans, a three factor solution displayed replicability and construct validity. The three factors were labelled as psycho-physiological distress, somatic distress, and arthro-neuromuscular distress, and were broadly similar to those described in previous studies of Gulf War veterans. A concordant three factor solution was also found for the comparison group subjects, with strong convergence of the factor loadings and factor scores across the two groups being displayed. Results did not display evidence of a unique pattern of self-reported symptoms among Gulf War veterans. Results also indicated that the differences between the groups lie in the degrees of expression of the three underlying factors, consistent with the well documented evidence of increased self-reported symptom prevalence in Gulf War veterans.

Utilization of Practice Session Average Inertial Load to Quantify College Football Injury Risk.

PubMed

Wilkerson, Gary B; Gupta, Ashish; Allen, Jeff R; Keith, Clay M; Colston, Marisa A

2016-09-01

Wilkerson, GB, Gupta, A, Allen, JR, Keith, CM, and Colston, MA. Utilization of practice session average inertial load to quantify college football injury risk. J Strength Cond Res 30(9): 2369-2374, 2016-Relatively few studies have investigated the potential injury prevention value of data derived from recently developed wearable technology for measurement of body mass accelerations during the performance of sport-related activities. The available evidence has been derived from studies focused on avoidance of overtraining syndrome, which is believed to induce a chronically fatigued state that can be identified through monitoring of inertial load accumulation. Reduced variability in movement patterns is also believed to be an important injury risk factor, but no evidence currently exists to guide interpretation of data derived from inertial measurement units (IMUs) in this regard. We retrospectively analyzed archived data for a cohort of 45 National Collegiate Athletic Association Division 1-football bowl subdivision football players who wore IMUs on the upper back during practice sessions to quantify any associations between average inertial load measured during practice sessions and occurrence of musculoskeletal sprains and strains. Both the coefficient of variation for average inertial load and frequent exposure to game conditions were found to be strongly associated with injury occurrence. Having either or both of the 2 risk factors provided strong discrimination between injured and noninjured players (χ = 9.048; p = 0.004; odds ratio = 8.04; 90% CI: 2.39, 27.03). Our findings may facilitate identification of individual football players who are likely to derive the greatest benefit from training activities designed to reduce injury risk through improved adaptability to rapidly changing environmental demands.

The dynamic natures of implant loading.

PubMed

Wang, Rui-Feng; Kang, Byungsik; Lang, Lisa A; Razzoog, Michael E

2009-06-01

A fundamental problem in fully understanding the dynamic nature of implant loading is the confusion that exists regarding the torque load delivered to the implant complex, the initial force transformation/stress/strain developed within the system during the implant complex assembly, and how the clamping forces at the interfaces and the preload stress impact the implant prior to any external loading. The purpose of this study was to create an accurately dimensioned finite element model with spiral threads and threaded bores included in the implant complex, positioned in a bone model, and to determine the magnitude and distribution of the force transformation/stress/strain patterns developed in the modeled implant system and bone and, thus, provide the foundational data for the study of the dynamic loading of dental implants prior to any external loading. An implant (Brånemark Mark III), abutment (CeraOne), abutment screw (Unigrip), and the bone surrounding the implant were modeled using HyperMesh software. The threaded interfaces between screw/implant and implant/bone were designed as a spiral thread helix assigned with specific coefficient of friction values. Assembly simulation using ABAQUS and LS-DYNA was accomplished by applying a 32-Ncm horizontal torque load on the abutment screw (Step 1), then decreasing the torque load to 0 Ncm to simulate the wrench removal (Step 2). The postscript data were collected and reviewed by HyperMesh. A regression analysis was used to depict the relationships between the torque load and the mechanical parameters. During the 32-Ncm tightening sequence, the abutment screw elongated 13.3 mum. The tightening torque generated a 554-N clamping force at the abutment/implant interface and a 522-N preload. The von Mises stress values were 248 MPa in the abutment at the abutment-implant interface, 765 MPa at the top of the screw shaft, 694 MPa at the bottom of the screw shaft, 1365 MPa in the top screw thread, and 21 MPa in the bone at the top of the implant-bone interface. This study also identified various characteristic isosurface stress patterns. The maximum stress magnitude to complete the von Mises stress joint pattern in the present model was 107 MPa during screw tightening, and was reduced to 104 MPa with removal of the wrench. Various specific stress patterns were identified within all elements of the implant complex during the assembly simulation. During the torque moment application, the abutment screw was elongated, and every 1.0-mum elongation of the screw was equivalent to a 47.9-N increase of the preload in the implant complex. The ideal index to determine the preload amount was the contact force at the interface between the screw threads and the threaded screw bore. The isosurface mode identified various characteristic stress patterns developed within the implant complex at the various interfaces during the assembly simulation. These patterns are the (1) spiral and ying-yang pattern of the XY stress, (2) spring, cap, clamping, and preload pattern of the ZZ stress, and (3) bone holding and joint pattern of the von Mises stress.

The effect of foot strike pattern on achilles tendon load during running.

PubMed

Almonroeder, Thomas; Willson, John D; Kernozek, Thomas W

2013-08-01

In this study we compared Achilles tendon loading parameters during barefoot running among females with different foot strike patterns using open-source computer muscle modeling software to provide dynamic simulations of running. Muscle forces of the gastrocnemius and soleus were estimated from experimental data collected in a motion capture laboratory during barefoot running for 11 runners utilizing a rearfoot strike (RFS) and 8 runners utilizing a non-RFS (NRFS) pattern. Our results show that peak Achilles tendon force occurred earlier in stance phase (p = 0.007), which contributed to a 15% increase in average Achilles tendon loading rate among participants adopting a NRFS pattern (p = 0.06). Stance time, step length, and the estimated number of steps per mile were similar between groups. However, runners with a NRFS pattern experienced 11% greater Achilles tendon impulse each step (p = 0.05) and nearly significantly greater Achilles tendon impulse per mile run (p = 0.06). This difference equates to an additional 47.7 body weights for each mile run with a NRFS pattern. Runners considering a NRFS pattern may want to account for these novel stressors and adapt training programs accordingly.

Biomass Combustions and Burning Emissions Inferred from GOES Fire Radiative Power

NASA Astrophysics Data System (ADS)

Zhang, X.; Kondragunta, S.; Schmidt, C.

2007-12-01

Biomass burning significantly affects air quality and climate changes. Current estimates of burning emissions are rather imprecise and vary markedly with different methodologies. This paper investigates biomass burning consumption and emissions using GOES (Geostationary Operational Environmental Satellites) WF_ABBA (Wildfire Automated Biomass Burning Algorithm) fire product. In doing this, we establish a set of representatives in diurnal patterns of half-hourly GOES Fire Radiative Power (FRP) for various ecosystems. The representative patterns are used to fill the missed and poor observations of half hourly FRP in GOES fire data for individual fire pixels. The simulated FRP is directly applied to the calculation of the biomass combusted during fire activities. The FRP-based biomass combustion is evaluated using the estimates using a traditional model which integrates burned area, fuel loading, and combustion factor. In the traditional model calculation, we derive burned areas from GOES WF_ABBA fire size. Fuel loading includes three different types (1) MODIS Vegetation Property-based Fuel System (MVPFS), (2) National Dangerous Rating Systems (NFDRS), and (3) the Fuel Characteristic Classification System (FCCS). By comparing the biomass combustions across the Contiguous United States (CONUS) from 2003-2005, we conclude that FRP is an effective tool to estimate the biomass burning emissions. Finally, we examine the temporal and spatial patterns in biomass combustions and emissions (PM2.5, CO, NH3) across the CONUS.

Cross-Modal Decoding of Neural Patterns Associated with Working Memory: Evidence for Attention-Based Accounts of Working Memory

PubMed Central

Majerus, Steve; Cowan, Nelson; Péters, Frédéric; Van Calster, Laurens; Phillips, Christophe; Schrouff, Jessica

2016-01-01

Recent studies suggest common neural substrates involved in verbal and visual working memory (WM), interpreted as reflecting shared attention-based, short-term retention mechanisms. We used a machine-learning approach to determine more directly the extent to which common neural patterns characterize retention in verbal WM and visual WM. Verbal WM was assessed via a standard delayed probe recognition task for letter sequences of variable length. Visual WM was assessed via a visual array WM task involving the maintenance of variable amounts of visual information in the focus of attention. We trained a classifier to distinguish neural activation patterns associated with high- and low-visual WM load and tested the ability of this classifier to predict verbal WM load (high–low) from their associated neural activation patterns, and vice versa. We observed significant between-task prediction of load effects during WM maintenance, in posterior parietal and superior frontal regions of the dorsal attention network; in contrast, between-task prediction in sensory processing cortices was restricted to the encoding stage. Furthermore, between-task prediction of load effects was strongest in those participants presenting the highest capacity for the visual WM task. This study provides novel evidence for common, attention-based neural patterns supporting verbal and visual WM. PMID:25146374

Computerized Modeling and Loaded Tooth Contact Analysis of Hypoid Gears Manufactured by Face Hobbing Process

NASA Astrophysics Data System (ADS)

Nishino, Takayuki

The face hobbing process has been widely applied in automotive industry. But so far few analytical tools have been developed. This makes it difficult for us to optimize gear design. To settle this situation, this study aims at developing a computerized tool to predict the running performances such as loaded tooth contact pattern, static transmission error and so on. First, based upon kinematical analysis of a cutting machine, a mathematical description of tooth surface generation is given. Second, based upon the theory of gearing and differential geometry, conjugate tooth surfaces are studied. Then contact lines are generated. Third, load distribution along contact lines is formulated. Last, the numerical model is validated by measuring loaded transmission error and loaded tooth contact pattern.

Cyclic Mechanical Loading Enhances Transport of Antibodies Into Articular Cartilage.

PubMed

DiDomenico, Chris D; Xiang Wang, Zhen; Bonassar, Lawrence J

2017-01-01

The goal of this study was to characterize antibody penetration through cartilage tissue under mechanical loading. Mechanical stimulation aids in the penetration of some proteins, but this effect has not characterized molecules such as antibodies (>100 kDa), which may hold some clinical value for treating osteoarthritis (OA). For each experiment, fresh articular cartilage plugs were obtained and exposed to fluorescently labeled antibodies while under cyclic mechanical load in unconfined compression for several hours. Penetration of these antibodies was quantified using confocal microscopy, and finite element (FE) simulations were conducted to predict fluid flow patterns within loaded samples. Transport enhancement followed a linear trend with strain amplitude (0.25-5%) and a nonlinear trend with frequency (0.25-2.60 Hz), with maximum enhancement found to be at 5% cyclic strain and 1 Hz, respectively. Regions of highest enhancement of transport within the tissue were associated with the regions of highest interstitial fluid velocity, as predicted from finite-element simulations. Overall, cyclic compression-enhanced antibody transport by twofold to threefold. To our knowledge, this is the first study to test how mechanical stimulation affects the diffusion of antibodies in cartilage and suggest further study into other important factors regarding macromolecular transport.

Electromyographic and Neuromuscular Force Patterns Associated with Unexpectedly Loaded Rapid Limb Movements.

ERIC Educational Resources Information Center

Richardson, Charles; Simmons, Roger W.

Bi-articular, unidirectional arm movements were studied to evaluate the electromyographic (EMG) and neuromuscular force patterns that occur when a limb is unexpectedly perturbed. A series of training trials were continued with a control load spring attached to the apparatus until a pre-specified criterion for learning was attained. The limb was…

The contribution of raised intraneuronal chloride to epileptic network activity.

PubMed

Alfonsa, Hannah; Merricks, Edward M; Codadu, Neela K; Cunningham, Mark O; Deisseroth, Karl; Racca, Claudia; Trevelyan, Andrew J

2015-05-20

Altered inhibitory function is an important facet of epileptic pathology. A key concept is that GABAergic activity can become excitatory if intraneuronal chloride rises. However, it has proved difficult to separate the role of raised chloride from other contributory factors in complex network phenomena, such as epileptic pathology. Therefore, we asked what patterns of activity are associated with chloride dysregulation by making novel use of Halorhodopsin to load clusters of mouse pyramidal cells artificially with Cl(-). Brief (1-10 s) activation of Halorhodopsin caused substantial positive shifts in the GABAergic reversal potential that were proportional to the charge transfer during the illumination and in adult neocortical pyramidal neurons decayed with a time constant of τ = 8.0 ± 2.8s. At the network level, these positive shifts in EGABA produced a transient rise in network excitability, with many distinctive features of epileptic foci, including high-frequency oscillations with evidence of out-of-phase firing (Ibarz et al., 2010). We show how such firing patterns can arise from quite small shifts in the mean intracellular Cl(-) level, within heterogeneous neuronal populations. Notably, however, chloride loading by itself did not trigger full ictal events, even with additional electrical stimulation to the underlying white matter. In contrast, when performed in combination with low, subepileptic levels of 4-aminopyridine, Halorhodopsin activation rapidly induced full ictal activity. These results suggest that chloride loading has at most an adjunctive role in ictogenesis. Our simulations also show how chloride loading can affect the jitter of action potential timing associated with imminent recruitment to an ictal event (Netoff and Schiff, 2002). Copyright © 2015 Alfonsa et al.

Modulation of weight off-loading level over body-weight supported locomotion training.

PubMed

Wang, Ping; Low, K H; Lim, Peter A C; McGregor, A H

2011-01-01

With the evolution of robotic systems to facilitate overground walking rehabilitation, it is important to understand the effect of robotic-aided body-weight supported loading on lower limb muscle activity, if we are to optimize neuromotor recovery. To achieve this objective, we have collected and studied electromyography (EMG) data from key muscles in the lower extremity from healthy subjects walking over a wide range of body-weight off-loading levels as provided by a bespoke gait robot. By examining the impact of body-weight off-loading, it was found that muscle activation patterns were sensitive to the level of off-loading. In addition, a large off-loading might introduce disturbance of muscle activation pattern, led to a wider range of motion in terms of dorsiflexion/plantarflexion. Therefore, any future overground training machine should be enhanced to exclude unnecessary effect of body off-loading in securing the sustaining upright posture and providing assist-as-needed BWS over gait rehabilitation. © 2011 IEEE

Using observed load distributions with a simple model to analyse the epidemiology of sea lice (Lepeophtheirus salmonis) on sea trout (Salmo trutta).

PubMed

Murray, Alexander G

2002-06-01

Sea lice are ectoparasites of salmonids that have been associated with the recent decline in sea trout numbers in north-west Europe. Observed patterns of louse load distribution between sea trout in the seas surrounding the UK, Ireland and Norway and a simple model have been used to analyse the epidemiology of lice. Loads are aggregated and deviate strongly from the Poisson distribution, although less than is observed with many other parasites. The louse numbers on fish from offshore sites are slightly less variable than for fish from coastal sites with comparable mean loads. Analysis of louse development stages and sexes shows that selection between hosts by sea lice plays a limited role. If host selection is absent, then associated poor condition would be caused by, not the cause of, high louse burdens; however the absence of such selection is not proved. Scenarios with infection that is patchy in space and time best generate the aggregated load patterns observed; these patches accord with observed swarms of copepodids. Prevalence patterns may indicate the movement of trout between environments. Control of copepodids in infection 'hot spots', either directly or through control of louse egg production in their catchment, may reduce louse loads on wild sea trout and, in particular, extreme and damaging loads.

Cumulative Socioeconomic Status Risk, Allostatic Load, and Adjustment: A Prospective Latent Profile Analysis With Contextual and Genetic Protective Factors

PubMed Central

Brody, Gene H.; Yu, Tianyi; Chen, Yi-fu; Kogan, Steven M.; Evans, Gary W.; Beach, Steven R. H.; Windle, Michael; Simons, Ronald L.; Gerrard, Meg; Gibbons, Frederick X.; Philibert, Robert A.

2012-01-01

The health disparities literature identified a common pattern among middle-aged African Americans that includes high rates of chronic disease along with low rates of psychiatric disorders despite exposure to high levels of cumulative SES risk. The current study was designed to test hypotheses about the developmental precursors to this pattern. Hypotheses were tested with a representative sample of 443 African American youths living in the rural South. Cumulative SES risk and protective processes were assessed at 11-13 years; psychological adjustment was assessed at ages 14-18 years; genotyping at the 5-HTTLPR was conducted at age 16 years; and allostatic load (AL) was assessed at age 19 years. A Latent Profile Analysis identified 5 profiles that evinced distinct patterns of SES risk, AL, and psychological adjustment, with 2 relatively large profiles designated as focal profiles: a physical health vulnerability profile characterized by high SES risk/high AL/low adjustment problems, and a resilient profile characterized by high SES risk/low AL/low adjustment problems. The physical health vulnerability profile mirrored the pattern found in the adult health disparities literature. Multinomial logistic regression analyses indicated that carrying an s allele at the 5-HTTLPR and receiving less peer support distinguished the physical health vulnerability profile from the resilient profile. Protective parenting and planful self-regulation distinguished both focal profiles from the other 3 profiles. The results suggest the public health importance of preventive interventions that enhance coping and reduce the effects of stress across childhood and adolescence. PMID:22709130

Cumulative socioeconomic status risk, allostatic load, and adjustment: a prospective latent profile analysis with contextual and genetic protective factors.

PubMed

Brody, Gene H; Yu, Tianyi; Chen, Yi-fu; Kogan, Steven M; Evans, Gary W; Beach, Steven R H; Windle, Michael; Simons, Ronald L; Gerrard, Meg; Gibbons, Frederick X; Philibert, Robert A

2013-05-01

The health disparities literature has identified a common pattern among middle-aged African Americans that includes high rates of chronic disease along with low rates of psychiatric disorders despite exposure to high levels of cumulative socioeconomic status (SES) risk. The current study was designed to test hypotheses about the developmental precursors to this pattern. Hypotheses were tested with a representative sample of 443 African American youths living in the rural South. Cumulative SES risk and protective processes were assessed at ages 11-13 years; psychological adjustment was assessed at ages 14-18 years; genotyping at the 5-HTTLPR was conducted at age 16 years; and allostatic load (AL) was assessed at age 19 years. A latent profile analysis identified 5 profiles that evinced distinct patterns of SES risk, AL, and psychological adjustment, with 2 relatively large profiles designated as focal profiles: a physical health vulnerability profile characterized by high SES risk/high AL/low adjustment problems, and a resilient profile characterized by high SES risk/low AL/low adjustment problems. The physical health vulnerability profile mirrored the pattern found in the adult health disparities literature. Multinomial logistic regression analyses indicated that carrying an s allele at the 5-HTTLPR and receiving less peer support distinguished the physical health vulnerability profile from the resilient profile. Protective parenting and planful self-regulation distinguished both focal profiles from the other 3 profiles. The results suggest the public health importance of preventive interventions that enhance coping and reduce the effects of stress across childhood and adolescence.

Recovery of Weak Factor Loadings When Adding the Mean Structure in Confirmatory Factor Analysis: A Simulation Study

PubMed Central

Ximénez, Carmen

2016-01-01

This article extends previous research on the recovery of weak factor loadings in confirmatory factor analysis (CFA) by exploring the effects of adding the mean structure. This issue has not been examined in previous research. This study is based on the framework of Yung and Bentler (1999) and aims to examine the conditions that affect the recovery of weak factor loadings when the model includes the mean structure, compared to analyzing the covariance structure alone. A simulation study was conducted in which several constraints were defined for one-, two-, and three-factor models. Results show that adding the mean structure improves the recovery of weak factor loadings and reduces the asymptotic variances for the factor loadings, particularly for the models with a smaller number of factors and a small sample size. Therefore, under certain circumstances, modeling the means should be seriously considered for covariance models containing weak factor loadings. PMID:26779071

Changes in spine loading patterns throughout the workday as a function of experience, lift frequency, and personality.

PubMed

Chany, Anne-Marie; Parakkat, Julia; Yang, Gang; Burr, Deborah L; Marras, William S

2006-01-01

Psychosocial stressors have been associated with low back pain reporting. However, response to psychosocial risk factors may be dependent on the individual's personality type that, in turn, can affect muscle recruitment and spine loading. This study explores how personality might be associated with spine loading during repetitive lifting performed throughout an entire work shift. Assess spine loading as a function of an individual's personality type during repetitive, long-term exposure to a materials handling tasks. Laboratory experiment where experienced and inexperienced participants performed repetitive, asymmetric lifts at various load and lift frequency levels throughout a series of 8-hour exposure periods. Spine loads were monitored throughout the work period. Twelve novice and 12 experienced materials handlers who were asymptomatic for back pain. Spine compression, anterior-posterior (A/P) shear, and lateral shear at the L5-S1 level. Participants were categorized into personality types based upon the Myers-Briggs personality type indicator. An electromyography-assisted biomechanical model was used to assess spine compression, A/P shear, and lateral shear throughout the exposure period. The results indicate that intuitors had higher shear spinal loading regardless of moment exposure, lift frequency, and time through the work period, compared with the sensor personality type. In addition, higher spine compressive and shear forces occurred in the perceiver personality compared with the judgers' personality trait, regardless of moment and, often, lift frequency. Novice lifters typically experienced greater spine loading. The results suggest that when there exists a personality-job environment mismatch, spinal loading increases via an increase in antagonistic co-contraction. The trends suggest that inherent personality characteristics may play a role in one's motor control strategies when performing a repetitive lifting task.

[Factors affecting the pressure distribution underneath the foot sole in ski boots].

PubMed

Schaff, P; Kulot, M; Hauser, W; Rosemeyer, B

1988-12-01

The determination of pressure patterns underneath the footsole inside skiboots, may reveal reasons for footpain and injury risk. In our study, a new developed 72 point measuring mat was used in 5 different skiboots. Data were collected in 10 subjects in different forward flexion positions. In addition a determination of the pressure distribution over the instep was done by means of single measuring points. The results proof, that a proper adapting along the dorsum of the foot does lower the forefoot load during flexion. A tightly closed and well adapted boot will lead to a significant reduction of the total load on the footsole. High shaft models show similar pressure patterns even at earlier forward flexion angles. A pressure related discrimination between rear entry and traditional boots, that was found along the tibia, was not the case underneath the footsole. The force transmission is mainly performed along the shaft of the boot. The effect of orthotics designed mainly to support steerability of the ski, is therefore doubtful. The results may help to improve our knowledge of the interaction between boot and skier and lead, together with future field research, to a reduction of equipment related injuries.

Flexural subsidence and basement tectonics of the Cretaceous Western Interior basin, United States

NASA Astrophysics Data System (ADS)

Pang, Ming; Nummedal, Dag

1995-02-01

The flexural subsidence history recorded in Cenomanian to early Campanian (97 to 80 Ma) strata in the Cretaceous U.S. Western Interior basin was studied with two-dimensional flexural backstripping techniques. Results indicate that the flexural subsidence resulting from thrust loading was superimposed on epeirogenic subsidence in the foreland basin. The flexural component exhibits significant spatial and temporal variations along both the strike and dip relative to the Sevier thrust belt. The greatest cumulative subsidence occurred in southwestern Wyoming and northern Utah. Concurrent subsidence in northwestern Montana and southern Utah was insignificant. Temporal trends in subsidence also show a distinct regional pattern. From the Cenomanian to late Turonian (97 to 90 Ma), subsidence rates were high in Utah and much lower in Wyoming and Montana. In contrast, during the Coniacian and Santonian (90 to 85 Ma) subsidence accelerated rapidly in Wyoming, increased slightly in Montana, and decreased in Utah. We suggest that these spatially and temporally varying subsidence patterns reflect the interplay of several geodynamic factors, including: (1) temporal and spatial variation in emplacement of the thrust loads, (2) segmentation of the basement into adjacent blocks with different rheological properties, (3) reactivation of basement fault trends, and (4) regional dynamic topographic effects.

A spatially explicit suspended-sediment load model for western Oregon

USGS Publications Warehouse

Wise, Daniel R.; O'Connor, Jim

2016-06-27

Knowledge of the regionally important patterns and factors in suspended-sediment sources and transport could support broad-scale, water-quality management objectives and priorities. Because of biases and limitations of this model, however, these results are most applicable for general comparisons and for broad areas such as large watersheds. For example, despite having similar area, precipitation, and land-use, the Umpqua River Basin generates 68 percent more suspended sediment than the Rogue River Basin, chiefly because of the large area of Coast Range sedimentary province in the Umpqua River Basin. By contrast, the Rogue River Basin contains a much larger area of Klamath terrane rocks, which produce significantly less suspended load, although recent fire disturbance (in 2002) has apparently elevated suspended sediment yields in the tributary Illinois River watershed. Fine-scaled analysis, however, will require more intensive, locally focused measurements.

Demographic, socioeconomic and nutritional determinants of daily versus non-daily sugar-sweetened and artificially sweetened beverage consumption.

PubMed

Mullie, P; Aerenhouts, D; Clarys, P

2012-02-01

The aim of this study was to determine the impact of demographic, socioeconomic and nutritional determinants on daily versus non-daily sugar-sweetened and artificially sweetened beverage consumption. Cross-sectional design in 1852 military men. Using mailed questionnaires, sugar-sweetened and artificially sweetened beverage consumption was recorded. Principal component analysis was used for dietary pattern analysis. Sugar-sweetened and artificially sweetened beverages were consumed daily by 36.3% and 33.2% of the participants, respectively. Age, body mass index (BMI), non-smoking and income were negatively related to sugar-sweetened beverage consumption. High BMI and trying to lose weight were related to artificially sweetened beverages consumption. Three major patterns were obtained from principal component analysis: first, the 'meat pattern', was loaded for red meats and processed meats; second, the 'healthy pattern', was loaded for tomatoes, fruit, whole grain, vegetables, fruit, fish, tea and nuts; finally, the 'sweet pattern' was loaded for sweets, desserts, snacks, high-energy drinks, high-fat dairy products and refined grains. The sugar-sweetened beverage consumption was strongly related with both the meat and sweet dietary patterns and inversely related to the healthy dietary pattern. The artificially sweetened beverage consumption was strongly related with the sweet and healthy dietary pattern. Daily consumption of sugar-sweetened beverages was inversely associated with a healthy dietary pattern. Daily consumption of artificially sweetened beverages was clearly associated with weight-loss intention.

Experimental observations on the decay of environmental DNA from bighead and silver carps

USGS Publications Warehouse

Lance, Richard F.; Klymus, Katy E.; Richter, Cathy; Guan, Xin; Farrington, Heather L.; Carr, Matthew R.; Thompson, Nathan; Chapman, Duane C.; Baerwaldt, Kelly L.

2017-01-01

Interest in the field of environmental DNA (eDNA) is growing rapidly and eDNA surveys are becoming an important consideration for aquatic resource managers dealing with invasive species. However, in order for eDNA monitoring to mature as a research and management tool, there are several critical knowledge gaps that must be filled. One such gap is the fate of eDNA materials in the aquatic environment. Understanding the environmental factors that influence the decay of eDNA and how these factors impact detection probabilities over time and space could have significant implications for eDNA survey design and data interpretation. Here we experimentally explore decay of eDNA associated with bighead carp (Hypophthalmichthys nobilis) biological waste collected from an aquaculture filtration system and with sperm collected from captive silver carp (H. molitrix), and how decay may be influenced by differing levels of water turbulence, temperature, microbial load, and pH. We found that the decay patterns of eDNA associated with both H. nobilis biological waste and H. molitrix milt significantly fit monophasic exponential decay curves. Secondly, we observed that the highest temperature we tested resulted in a decay half-life as much as 5.5× more rapid than the lowest temperature we tested. When we suppressed microbial loads in eDNA samples, we observed that overall losses of eDNA were reduced by about 2.5×. When we amended eDNA samples with pond water the half-life of eDNA was reduced by about 2.25×, despite relatively little apparent increase in the overall microbial load. This pattern indicated that species constituency of the microbial community, in addition to microbial load, might play a critical role in eDNA degradation. A shift in pH from 6.5 to 8.0 in the samples resulted in a 1.6× reduction in eDNA halflife. Water turbulence in our study had no apparent effect on eDNA decay. When we combined different temperature, pH, and microbial load treatments to create a rapid decay condition and a slow decay condition, and tracked eDNA decay over 91 days, we observed a 5.0× greater loss of eDNA by Day 5 under rapid decay conditions than under slow decay conditions. At the end of the trials, the differences in eDNA loss between the rapid decay and baseline and slow decay conditions were 0.1× and 3.3×, respectively. Our results strongly demonstrate the potential for environmental factors to influence eDNA fate and, thus, the interpretation of eDNA survey results.

An alternative method for centrifugal compressor loading factor modelling

NASA Astrophysics Data System (ADS)

Galerkin, Y.; Drozdov, A.; Rekstin, A.; Soldatova, K.

2017-08-01

The loading factor at design point is calculated by one or other empirical formula in classical design methods. Performance modelling as a whole is out of consideration. Test data of compressor stages demonstrates that loading factor versus flow coefficient at the impeller exit has a linear character independent of compressibility. Known Universal Modelling Method exploits this fact. Two points define the function - loading factor at design point and at zero flow rate. The proper formulae include empirical coefficients. A good modelling result is possible if the choice of coefficients is based on experience and close analogs. Earlier Y. Galerkin and K. Soldatova had proposed to define loading factor performance by the angle of its inclination to the ordinate axis and by the loading factor at zero flow rate. Simple and definite equations with four geometry parameters were proposed for loading factor performance calculated for inviscid flow. The authors of this publication have studied the test performance of thirteen stages of different types. The equations are proposed with universal empirical coefficients. The calculation error lies in the range of plus to minus 1,5%. The alternative model of a loading factor performance modelling is included in new versions of the Universal Modelling Method.

Lumbopelvic muscle activation patterns in three stances under graded loading conditions: Proposing a tensegrity model for load transfer through the sacroiliac joints.

PubMed

Pardehshenas, Hamed; Maroufi, Nader; Sanjari, Mohammad Ali; Parnianpour, Mohamad; Levin, Stephen M

2014-10-01

According to the conventional arch model of the pelvis, stability of the sacroiliac joints may require a predominance of form and force closure mechanisms: the greater the vertical shear force at the sacroiliac joints, the greater the reliance on self-bracing by horizontally or obliquely oriented muscles (such as the internal oblique). But what happens to the arch model when a person stands on one leg? In such cases, the pelvis no longer has imposts, leaving both the arch, and the arch model theory, without support. Do lumbopelvic muscle activation patterns in one-legged stances under load suggest compatibility with a different model? This study compares lumbopelvic muscle activation patterns in two-legged and one-legged stances in response to four levels of graded trunk loading in order to further our understanding the stabilization of the sacroiliac joints. Thirty male subjects experienced four levels of trunk loading (0%, 5%, 10% and 15% of body weight) by holding a bucket at one side, at three conditions: 1) two-legged standing with the bucket in the dominant hand, 2) ipsilateral loading: one-legged standing with the bucket in the dominant hand while using the same-side leg, and 3) contralateral loading: one-legged standing using the same leg used in condition 2, but with the bucket in the non-dominant hand. During these tasks, EMG signals from eight lumbopelvic muscles were collected. ANOVA with repeated design was performed on normalized EMG's to test the main effect of load and condition, and interaction effects of load by condition. Latissimus dorsi and erector spinae muscles showed an antagonistic pattern of activity toward the direction of load which may suggest these muscles as lateral trunk stabilizers. Internal oblique muscles showed a co-activation pattern with increasing task demand, which may function to increase lumbopelvic stability (P < 0.05). No unilateral pattern of the internal obliques was observed during all trials. Our results suggest that the lumbopelvic region uses a similar strategy for load transfer in both double and single leg support positions which is not compatible with the arch analogy. Our findings are more consistent with a suspensory system (wire-spoke wheel model). If our proposed model holds true, the pelvic ring can only be integrated by adjusting tension in the spokes and by preserving rim integrity or continuity. Thus, we propose that in order to restore tension integrity throughout the pelvic ring, efforts to unlock restrictions, muscular correction of positional faults and lumbopelvic or even respiratory exercises following sacroiliac joint dysfunctions must be taken into consideration. Our hypothetical model may initiate thinking and act as a guide to future work based on a biomechanical approach to the problem of sacroiliac joint dysfunction. Copyright © 2014 Elsevier Ltd. All rights reserved.

Polymorphisms in Plasmodium vivax Circumsporozoite Protein (CSP) Influence Parasite Burden and Cytokine Balance in a Pre-Amazon Endemic Area from Brazil

PubMed Central

Ribeiro, Bruno de Paulo; Cassiano, Gustavo Capatti; de Souza, Rodrigo Medeiros; Cysne, Dalila Nunes; Grisotto, Marcos Augusto Grigolin; de Azevedo dos Santos, Ana Paula Silva; Marinho, Cláudio Romero Farias; Machado, Ricardo Luiz Dantas; Nascimento, Flávia Raquel Fernandes

2016-01-01

Mechanisms involved in severe P. vivax malaria remain unclear. Parasite polymorphisms, parasite load and host cytokine profile may influence the course of infection. In this study, we investigated the influence of circumsporozoite protein (CSP) polymorphisms on parasite load and cytokine profile in patients with vivax malaria. A cross-sectional study was carried out in three cities: São Luís, Cedral and Buriticupu, Maranhão state, Brazil, areas of high prevalence of P. vivax. Interleukin (IL)-2, IL-4, IL-10, IL-6, IL-17, tumor necrosis factor alpha (TNF-α, interferon gamma (IFN-γ and transforming growth factor beta (TGF-β were quantified in blood plasma of patients and in supernatants from peripheral blood mononuclear cell (PBMC) cultures. Furthermore, the levels of cytokines and parasite load were correlated with VK210, VK247 and P. vivax-like CSP variants. Patients infected with P. vivax showed increased IL-10 and IL-6 levels, which correlated with the parasite load, however, in multiple comparisons, only IL-10 kept this association. A regulatory cytokine profile prevailed in plasma, while an inflammatory profile prevailed in PBMC culture supernatants and these patterns were related to CSP polymorphisms. VK247 infected patients showed higher parasitaemia and IL-6 concentrations, which were not associated to IL-10 anti-inflammatory effect. By contrast, in VK210 patients, these two cytokines showed a strong positive correlation and the parasite load was lower. Patients with the VK210 variant showed a regulatory cytokine profile in plasma, while those infected with the VK247 variant have a predominantly inflammatory cytokine profile and higher parasite loads, which altogether may result in more complications in infection. In conclusion, we propose that CSP polymorphisms is associated to the increase of non-regulated inflammatory immune responses, which in turn may be associated with the outcome of infection. PMID:26943639

Comparison of two parametric methods to estimate pesticide mass loads in California's Central Valley

USGS Publications Warehouse

Saleh, Dina K.; Lorenz, David L.; Domagalski, Joseph L.

2011-01-01

Mass loadings were calculated for four pesticides in two watersheds with different land uses in the Central Valley, California, by using two parametric models: (1) the Seasonal Wave model (SeaWave), in which a pulse signal is used to describe the annual cycle of pesticide occurrence in a stream, and (2) the Sine Wave model, in which first-order Fourier series sine and cosine terms are used to simulate seasonal mass loading patterns. The models were applied to data collected during water years 1997 through 2005. The pesticides modeled were carbaryl, diazinon, metolachlor, and molinate. Results from the two models show that the ability to capture seasonal variations in pesticide concentrations was affected by pesticide use patterns and the methods by which pesticides are transported to streams. Estimated seasonal loads compared well with results from previous studies for both models. Loads estimated by the two models did not differ significantly from each other, with the exceptions of carbaryl and molinate during the precipitation season, where loads were affected by application patterns and rainfall. However, in watersheds with variable and intermittent pesticide applications, the SeaWave model is more suitable for use on the basis of its robust capability of describing seasonal variation of pesticide concentrations.

The importance of age, sex and place in understanding socioeconomic inequalities in allostatic load: Evidence from the Scottish Health Survey (2008-2011).

PubMed

Robertson, Tony; Watts, Eleanor

2016-02-09

Given the broad spectrum of health and wellbeing outcomes that are patterned by socioeconomic position (SEP), it has been suggested that there may be common biological pathways linking SEP and health. Allostatic load is one such pathway, which aims to measure cumulative burden/dysregulation across multiple physiological systems. This study aimed to determine the contextual and demographic factors (age, sex and place) that may be important in better understanding the links between lower SEP and higher allostatic load. Data were from a nationally representative sample of adults (18+): the Scottish Health Survey (2008-2011). Higher SEP ('1') was defined as having 'Higher'-level, secondary school qualifications versus having lower level or no qualifications ('0'). For allostatic load, a range of 10 biomarkers across the cardiovascular, metabolic and immune systems were used. Respondents were scored "1" for each biomarker that fell into the highest quartile of risk. Linear regressions were run in STATA, including SEP, age (continuous and as a 7-category variable), sex (male/female), urbanity (a 5-category variable ranging from primary cities to remote rural areas) and geographical location (based on 10 area-level healthboards). Interactions between SEP and each predictor, as well as stratified analyses, were tested. Lower SEP was associated with higher allostatic load even after adjusting for age, sex and place (b = -0.631, 95 % CI -0.795, -0.389, p < 0.001). There was no significant effect moderation between SEP and age, sex or place. Stratified analysis did show that the inequality identified in the baseline models widened with age, becoming significant at ages 35-44, before narrowing at older ages (75+). There was no difference by sex, but more mixed findings with regards place (urbanity or geographical location), with a mix of significant and non-significant results by SEP that did not appear to follow any pattern. Inequalities in allostatic load by educational attainment, as a measure of SEP, are consistent with age, sex and place. However, these stratified analyses showed that these inequalities did widen with age, before narrowing in later life, matching the patterns seen with other objective and subjective health measures. However, effect moderation analysis did not support evidence of a statistically significant interaction between age and SEP. Context remains an important feature in understanding and potentially addressing inequalities, although may be less of an issue in terms of physiological burden.

T-Pattern Analysis and Cognitive Load Manipulation to Detect Low-Stake Lies: An Exploratory Study.

PubMed

Diana, Barbara; Zurloni, Valentino; Elia, Massimiliano; Cavalera, Cesare; Realdon, Olivia; Jonsson, Gudberg K; Anguera, M Teresa

2018-01-01

Deception has evolved to become a fundamental aspect of human interaction. Despite the prolonged efforts in many disciplines, there has been no definite finding of a univocally "deceptive" signal. This work proposes an approach to deception detection combining cognitive load manipulation and T-pattern methodology with the objective of: (a) testing the efficacy of dual task-procedure in enhancing differences between truth tellers and liars in a low-stakes situation; (b) exploring the efficacy of T-pattern methodology in discriminating truthful reports from deceitful ones in a low-stakes situation; (c) setting the experimental design and procedure for following research. We manipulated cognitive load to enhance differences between truth tellers and liars, because of the low-stakes lies involved in our experiment. We conducted an experimental study with a convenience sample of 40 students. We carried out a first analysis on the behaviors' frequencies coded through the observation software, using SPSS (22). The aim was to describe shape and characteristics of behavior's distributions and explore differences between groups. Datasets were then analyzed with Theme 6.0 software which detects repeated patterns (T-patterns) of coded events (non-verbal behaviors) that regularly or irregularly occur within a period of observation. A descriptive analysis on T-pattern frequencies was carried out to explore differences between groups. An in-depth analysis on more complex patterns was performed to get qualitative information on the behavior structure expressed by the participants. Results show that the dual-task procedure enhances differences observed between liars and truth tellers with T-pattern methodology; moreover, T-pattern detection reveals a higher variety and complexity of behavior in truth tellers than in liars. These findings support the combination of cognitive load manipulation and T-pattern methodology for deception detection in low-stakes situations, suggesting the testing of directional hypothesis on a larger probabilistic sample of population.

T-Pattern Analysis and Cognitive Load Manipulation to Detect Low-Stake Lies: An Exploratory Study

PubMed Central

Diana, Barbara; Zurloni, Valentino; Elia, Massimiliano; Cavalera, Cesare; Realdon, Olivia; Jonsson, Gudberg K.; Anguera, M. Teresa

2018-01-01

Deception has evolved to become a fundamental aspect of human interaction. Despite the prolonged efforts in many disciplines, there has been no definite finding of a univocally “deceptive” signal. This work proposes an approach to deception detection combining cognitive load manipulation and T-pattern methodology with the objective of: (a) testing the efficacy of dual task-procedure in enhancing differences between truth tellers and liars in a low-stakes situation; (b) exploring the efficacy of T-pattern methodology in discriminating truthful reports from deceitful ones in a low-stakes situation; (c) setting the experimental design and procedure for following research. We manipulated cognitive load to enhance differences between truth tellers and liars, because of the low-stakes lies involved in our experiment. We conducted an experimental study with a convenience sample of 40 students. We carried out a first analysis on the behaviors’ frequencies coded through the observation software, using SPSS (22). The aim was to describe shape and characteristics of behavior’s distributions and explore differences between groups. Datasets were then analyzed with Theme 6.0 software which detects repeated patterns (T-patterns) of coded events (non-verbal behaviors) that regularly or irregularly occur within a period of observation. A descriptive analysis on T-pattern frequencies was carried out to explore differences between groups. An in-depth analysis on more complex patterns was performed to get qualitative information on the behavior structure expressed by the participants. Results show that the dual-task procedure enhances differences observed between liars and truth tellers with T-pattern methodology; moreover, T-pattern detection reveals a higher variety and complexity of behavior in truth tellers than in liars. These findings support the combination of cognitive load manipulation and T-pattern methodology for deception detection in low-stakes situations, suggesting the testing of directional hypothesis on a larger probabilistic sample of population. PMID:29551986

A Risk-Based Approach to Variable Load Configuration Validation in Steam Sterilization: Application of PDA Technical Report 1 Load Equivalence Topic.

PubMed

Pavell, Anthony; Hughes, Keith A

2010-01-01

This article describes a method for achieving the load equivalence model, described in Parenteral Drug Association Technical Report 1, using a mass-based approach. The item and load bracketing approach allows for mixed equipment load size variation for operational flexibility along with decreased time to introduce new items to the operation. The article discusses the utilization of approximately 67 items/components (Table IV) identified for routine sterilization with varying quantities required weekly. The items were assessed for worst-case identification using four temperature-related criteria. The criteria were used to provide a data-based identification of worst-case items, and/or item equivalence, to carry forward into cycle validation using a variable load pattern. The mass approach to maximum load determination was used to bracket routine production use and allows for variable loading patterns. The result of the item mapping and load bracketing data is "a proven acceptable range" of sterilizing conditions including loading configuration and location. The application of these approaches, while initially more time/test-intensive than alternate approaches, provides a method of cycle validation with long-term benefit of ease of ongoing qualification, minimizing time and requirements for new equipment qualification for similar loads/use, and for rapid and rigorous assessment of new items for sterilization.

Rare earth elements in river waters

NASA Technical Reports Server (NTRS)

Goldstein, Steven J.; Jacobsen, Stein B.

1988-01-01

To characterize the input to the oceans of rare earth elements (REE) in the dissolved and the suspended loads of rivers, the REE concentrations were measured in samples of Amazon, Indus, Mississippi, Murray-Darling, and Ohio rivers and in samples of smaller rivers that had more distinct drainage basin lithology and water chemistry. It was found that, in the suspended loads of small rivers, the REE pattern was dependent on drainage basin geology, whereas the suspended loads in major rivers had relatively uniform REE patterns and were heavy-REE depleted relative to the North American Shale composite (NASC). The dissolved loads in the five major rivers had marked relative heavy-REE enrichments, relative to the NASC and the suspended material, with the (La/Yb)N ratio of about 0.4 (as compared with the ratio of about 1.9 in suspended loads).

Specimen-specific modeling of hip fracture pattern and repair.

PubMed

Ali, Azhar A; Cristofolini, Luca; Schileo, Enrico; Hu, Haixiang; Taddei, Fulvia; Kim, Raymond H; Rullkoetter, Paul J; Laz, Peter J

2014-01-22

Hip fracture remains a major health problem for the elderly. Clinical studies have assessed fracture risk based on bone quality in the aging population and cadaveric testing has quantified bone strength and fracture loads. Prior modeling has primarily focused on quantifying the strain distribution in bone as an indicator of fracture risk. Recent advances in the extended finite element method (XFEM) enable prediction of the initiation and propagation of cracks without requiring a priori knowledge of the crack path. Accordingly, the objectives of this study were to predict femoral fracture in specimen-specific models using the XFEM approach, to perform one-to-one comparisons of predicted and in vitro fracture patterns, and to develop a framework to assess the mechanics and load transfer in the fractured femur when it is repaired with an osteosynthesis implant. Five specimen-specific femur models were developed from in vitro experiments under a simulated stance loading condition. Predicted fracture patterns closely matched the in vitro patterns; however, predictions of fracture load differed by approximately 50% due to sensitivity to local material properties. Specimen-specific intertrochanteric fractures were induced by subjecting the femur models to a sideways fall and repaired with a contemporary implant. Under a post-surgical stance loading, model-predicted load sharing between the implant and bone across the fracture surface varied from 59%:41% to 89%:11%, underscoring the importance of considering anatomic and fracture variability in the evaluation of implants. XFEM modeling shows potential as a macro-level analysis enabling fracture investigations of clinical cohorts, including at-risk groups, and the design of robust implants. © 2013 Published by Elsevier Ltd.

Engineering blood vessels through micropatterned co-culture of vascular endothelial and smooth muscle cells on bilayered electrospun fibrous mats with pDNA inoculation.

PubMed

Liu, Yaowen; Lu, Jinfu; Li, Huinan; Wei, Jiaojun; Li, Xiaohong

2015-01-01

Although engineered blood vessels have seen important advances during recent years, proper mechanical strength and vasoactivity remain unsolved problems. In the current study, micropatterned fibrous mats were created to load smooth muscle cells (SMC), and a co-culture with endothelial cells (EC) was established through overlaying on an EC-loaded flat fibrous mat to mimic the layered structure of a blood vessel. A preferential distribution of SMC was determined in the patterned regions throughout the fibrous scaffolds, and aligned fibers in the patterned regions provided topological cues to guide the orientation of SMC with intense actin filaments and extracellular matrix (ECM) production in a circumferential direction. Plasmid DNA encoding basic fibroblast growth factors and vascular endothelial growth factor were integrated into electrospun fibers as biological cues to promote SMC infiltration into fibrous mats, and the viability and ECM production of both EC and SMC. The layered fibrous mats with loaded EC and SMC were wrapped into a cylinder, and engineered vessels were obtained with compact EC and SMC layers after co-culture for 3 months. Randomly oriented ECM productions of EC formed a continuous endothelium covering the entire lumenal surface, and a high alignment of ECM was shown in the circumferential direction of SMC layers. The tensile strength, strain at failure and suture retention strength were higher than those of the human femoral artery, and the burst pressure and radial compliance were in the same range as the human saphenous vein, indicating potential as blood vessel substitutes for transplantation in vivo. Thus, the establishment of topographical cues and biochemical signals in fibrous scaffolds demonstrates advantages in modulating cellular behavior and organization found in complex multicellular tissues. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Modelling soil properties in a crop field located in Croatia

NASA Astrophysics Data System (ADS)

Bogunovic, Igor; Pereira, Paulo; Millan, Mesic; Percin, Aleksandra; Zgorelec, Zeljka

2016-04-01

Development of tillage activities had negative effects on soil quality as destruction of soil horizons, compacting and aggregates destruction, increasing soil erosion and loss of organic matter. For a better management in order to mitigate the effects of intensive soil management in land degradation it is fundamental to map the spatial distribution of soil properties (Brevik et al., 2016). The understanding the distribution of the variables in space is very important for a sustainable management, in order to identify areas that need a potential intervention and decrease the economic losses (Galiati et al., 2016). The objective of this work is study the spatial distribution of some topsoil properties as clay, fine silt, coarse silt, fine sand, coarse sand, penetration resistance, moisture and organic matter in a crop field located in Croatia. A grid with 275x25 (625 m2) was designed and a total of 48 samples were collected. Previous to data modelling, data normality was checked using the Shapiro wilk-test. As in previous cases (Pereira et al., 2015), data did not followed the normal distribution, even after a logarithmic (Log), square-root, and box cox transformation. Thus, for modeling proposes, we used the log transformed data, since was the closest to the normality. In order to identify groups among the variables we applied a principal component analysis (PCA), based on the correlation matrix. On average clay content was 15.47% (±3.23), fine silt 24.24% (±4.08), coarse silt 35.34% (±3.12), fine sand 20.93% (±4.68), coarse sand 4.02% (±1.69), penetration resistance 0.66 MPa (±0.28), organic matter 1.51% (±0.25) and soil moisture 32.04% (±3.27). The results showed that the PCA identified three factors explained at least one of the variables. The first factor had high positive loadings in soil clay, fine silt and organic matter and a high negative loading in fine sand. The second factor had high positive loadings in coarse sand and moisture and a high negative loading in coarse silt. Finally, the factor 3 had a positive loading in penetration resistance. The loadings of these three factors were mapped using ordinary kriging method. The analysis of incremental spatial correlation identified that the highest spatial correlation in the factor 1 was identified at 41.87 m, in factor 2 at 75.61 m and factor 3 at 143.9 m. In the case of factor 2, the maximum peak of spatial autocorrelation was significant at a p<0.05. This showed that the variable has a random distribution, as confirmed with the Moran's I spatial correlation analysis. In relation to the other factors the maximum peaks were significantly clustered at a p<0.001. These results suggested that the each factor has a different spatial pattern and the studied soil properties explained by each factor had a different spatial distribution. References Breivik, E., Baumgarten, A., Calzolari, C., Miller, B., Pereira, P., Kabala, C., Jordán, A. Soil mapping, classification, and modelling: history and future directions. Geoderma, 264, Part B, 256-274. Galiati, A., Gristina, L., Crescimanno, Barone, E., Novara, A. (2016) Towards more efficient incentives for agri-environment measures in degraded and eroded vineyards. Land Degradation and Development, DOI: 10.1002/ldr.2389 Pereira, P., Cerdà, A., Úbeda, X., Mataix-Solera, J. Arcenegui, V., Zavala, L. (2015) Modelling the impacts of wildfire on ash thickness in a short-term period, Land Degradation and Development, 26, 180-192.

The Factor Structure of Effortful Control and Measurement Invariance Across Ethnicity and Sex in a High-Risk Sample

PubMed Central

Huerta, Snjezana; Zerr, Argero A.; Eisenberg, Nancy; Spinrad, Tracy L.; Valiente, Carlos; Di Giunta, Laura; Pina, Armando A.; Eggum, Natalie D.; Sallquist, Julie; Edwards, Alison; Kupfer, Anne; Lonigan, Christopher J.; Phillips, Beth M.; Wilson, Shauna B.; Clancy-Menchetti, Jeanine; Landry, Susan H.; Swank, Paul R.; Assel, Michael A.; Taylor, Heather B.

2010-01-01

Measurement invariance of a one-factor model of effortful control (EC) was tested for 853 low-income preschoolers (M age = 4.48 years). Using a teacher-report questionnaire and seven behavioral measures, configural invariance (same factor structure across groups), metric invariance (same pattern of factor loadings across groups), and partial scalar invariance (mostly the same intercepts across groups) were established across ethnicity (European Americans, African Americans and Hispanics) and across sex. These results suggest that the latent construct of EC behaved in a similar way across ethnic groups and sex, and that comparisons of mean levels of EC are valid across sex and probably valid across ethnicity, especially when larger numbers of tasks are used. The findings also support the use of diverse behavioral measures as indicators of a single latent EC construct. PMID:20593008

Dynamic pressurization induces transition of notochordal cells to a mature phenotype while retaining production of important patterning ligands from development

PubMed Central

2013-01-01

Introduction Notochordal cells (NCs) pattern aneural and avascular intervertebral discs (IVDs), and their disappearance, is associated with onset of IVD degeneration. This study induced and characterized the maturation of nucleus pulposus (NP) tissue from a gelatinous NC-rich structure to a matrix-rich structure populated by small NP cells using dynamic pressurization in an ex vivo culture model, and also identified soluble factors from NCs with therapeutic potential. Methods Porcine NC-rich NP tissue was cultured and loaded with hydrostatic pressure (0.5 to 2 MPa at 0.1 Hz for 2 hours) either Daily, for 1 Dose, or Control (no pressurization) groups for up to eight days. Cell phenotype and tissue maturation was characterized with measurements of cell viability, cytomorphology, nitric oxide, metabolic activity, matrix composition, gene expression, and proteomics. Results Daily pressurization induced transition of NCs to small NP cells with 73.8%, 44%, and 28% NCs for Control, 1 Dose and Daily groups, respectively (P < 0.0002) and no relevant cell death. Dynamic loading matured NP tissue by significantly increasing metabolic activity and accumulating Safranin-O-stained matrix. Load-induced maturation was also apparent from the significantly decreased glycolytic, cytoskeletal (Vimentin) and stress-inducible (HSP70) proteins assessed with proteomics. Loading increased the production of bioactive proteins Sonic Hedgehog (SHH) and Noggin, and maintained Semaphorin3A (Sema3A). Discussion NP tissue maturation was induced from dynamic hydrostatic pressurization in a controlled ex vivo environment without influence from systemic effects or surrounding structures. NCs transitioned into small nonvacuolated NP cells probably via differentiation as evidenced by high cell viability, lack of nitric oxide and downregulation of stress-inducible and cytoskeletal proteins. SHH, Sema3A, and Noggin, which have patterning and neurovascular-inhibiting properties, were produced in both notochordal and matured porcine NP. Results therefore provide an important piece of evidence suggesting the transition of NCs to small NP cells is a natural part of aging and not the initiation of degeneration. Bioactive candidates identified from young porcine IVDs may be isolated and harnessed for therapies to target discogenic back pain. PMID:24427812

Dynamic pressurization induces transition of notochordal cells to a mature phenotype while retaining production of important patterning ligands from development.

PubMed

Purmessur, Devina; Guterl, Clare C; Cho, Samuel K; Cornejo, Marisa C; Lam, Ying W; Ballif, Bryan A; Laudier, James C Iatridis; Iatridis, James C

2013-01-01

Notochordal cells (NCs) pattern aneural and avascular intervertebral discs (IVDs), and their disappearance, is associated with onset of IVD degeneration. This study induced and characterized the maturation of nucleus pulposus (NP) tissue from a gelatinous NC-rich structure to a matrix-rich structure populated by small NP cells using dynamic pressurization in an ex vivo culture model, and also identified soluble factors from NCs with therapeutic potential. Porcine NC-rich NP tissue was cultured and loaded with hydrostatic pressure (0.5 to 2 MPa at 0.1 Hz for 2 hours) either Daily, for 1 Dose, or Control (no pressurization) groups for up to eight days. Cell phenotype and tissue maturation was characterized with measurements of cell viability, cytomorphology, nitric oxide, metabolic activity, matrix composition, gene expression, and proteomics. Daily pressurization induced transition of NCs to small NP cells with 73.8%, 44%, and 28% NCs for Control, 1 Dose and Daily groups, respectively (P < 0.0002) and no relevant cell death. Dynamic loading matured NP tissue by significantly increasing metabolic activity and accumulating Safranin-O-stained matrix. Load-induced maturation was also apparent from the significantly decreased glycolytic, cytoskeletal (Vimentin) and stress-inducible (HSP70) proteins assessed with proteomics. Loading increased the production of bioactive proteins Sonic Hedgehog (SHH) and Noggin, and maintained Semaphorin3A (Sema3A). NP tissue maturation was induced from dynamic hydrostatic pressurization in a controlled ex vivo environment without influence from systemic effects or surrounding structures. NCs transitioned into small nonvacuolated NP cells probably via differentiation as evidenced by high cell viability, lack of nitric oxide and downregulation of stress-inducible and cytoskeletal proteins. SHH, Sema3A, and Noggin, which have patterning and neurovascular-inhibiting properties, were produced in both notochordal and matured porcine NP. Results therefore provide an important piece of evidence suggesting the transition of NCs to small NP cells is a natural part of aging and not the initiation of degeneration. Bioactive candidates identified from young porcine IVDs may be isolated and harnessed for therapies to target discogenic back pain.

Partnering with patients using social media to develop a hypertension management instrument.

PubMed

Kear, Tamara; Harrington, Magdalena; Bhattacharya, Anand

2015-09-01

Hypertension is a lifelong condition; thus, long-term adherence to lifestyle modification, self-monitoring, and medication regimens remains a challenge for patients. The aim of this study was to develop a patient-reported hypertension instrument that measured attitudes, lifestyle behaviors, adherence, and barriers to hypertension management using patient-reported outcome data. The study was conducted using the Open Research Exchange software platform created by PatientsLikeMe. A total of 360 participants completed the psychometric phase of the study; incomplete responses were obtained from 147 patients, and 150 patients opted out. Principal component analysis with orthogonal (varimax) rotation was executed on a data set with all completed responses (N = 249) and applied to 43 items. Based on the review of the factor solution, eigenvalues, and item loadings, 16 items were eliminated and model with 29 items was tested. The process was repeated two more times until final model with 14 items was established. In interpreting the rotated factor pattern, an item was said to load on any given component if the factor loading was ≥0.40 for that component and was <0.40 for the other. In addition to the newly generated instrument, demographic and self-reported clinical characteristics of the study participants such as the type of prescribed hypertension medications, frequency of blood pressure monitoring, and comorbid conditions were examined. The Open Research Exchange platform allowed for ongoing input from patients through each stage of the 14-item instrument development. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Cross-Modal Decoding of Neural Patterns Associated with Working Memory: Evidence for Attention-Based Accounts of Working Memory.

PubMed

Majerus, Steve; Cowan, Nelson; Péters, Frédéric; Van Calster, Laurens; Phillips, Christophe; Schrouff, Jessica

2016-01-01

Recent studies suggest common neural substrates involved in verbal and visual working memory (WM), interpreted as reflecting shared attention-based, short-term retention mechanisms. We used a machine-learning approach to determine more directly the extent to which common neural patterns characterize retention in verbal WM and visual WM. Verbal WM was assessed via a standard delayed probe recognition task for letter sequences of variable length. Visual WM was assessed via a visual array WM task involving the maintenance of variable amounts of visual information in the focus of attention. We trained a classifier to distinguish neural activation patterns associated with high- and low-visual WM load and tested the ability of this classifier to predict verbal WM load (high-low) from their associated neural activation patterns, and vice versa. We observed significant between-task prediction of load effects during WM maintenance, in posterior parietal and superior frontal regions of the dorsal attention network; in contrast, between-task prediction in sensory processing cortices was restricted to the encoding stage. Furthermore, between-task prediction of load effects was strongest in those participants presenting the highest capacity for the visual WM task. This study provides novel evidence for common, attention-based neural patterns supporting verbal and visual WM. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Land use impacts on lake water quality in Alytus region (Lithuania)

NASA Astrophysics Data System (ADS)

Pereira, Paulo; Laukonis, Rymvidas

2016-04-01

Land use has important impacts on soils, surface and ground water quality. Urban agricultural areas are an important source of pollutants, which can reach lakes through surface runoff and underground circulation. Human intervention in the landscape is one of the major causes pollution and land degradation, thus it is very important to understand the impacts of and use on environment and if they have some spatial pattern (Pereira et al., 2013, 2015; Brevik et al., 2016). The identification of the spatial pattern of lakes pollution is in Alytus area (Lithuania) is fundamental, since they provide an important range of ecosystem services to local communities, including food and recreational activities. Thus, the degradation of these environments can induce important economic losses. In this context, it is import to identify the areas with high pollutant accumulation and the environmental and human factors responsible for it. The objective of this work is to study identify the amount of some important nutrients resultant from human activities in lake water quality in Alytus region (Lithuania). Alytus region is located in southern part of Lithuania and has an approximate area of 40 km2. Inside this region we analyzed several water quality parameters of 55 lakes, including, pH, electrical conductivity (EC), suspended materials (SM), water clarity (WC) biochemical oxygen demand (BDO), total phosphorous (TP), total Nitrogen (TN), dissolved organic carbon (DOC), as other environmental variables as altitude, lake maximum deep (MD), lake area and land use according Corine land cover classification (CLC2006). Previous to data analysis, data normality and homogeneity of the variances, was assessed with the Shapiro-wilk and Leven's test, respectively. The majority of the data did not respect the Gaussian distribution and the heteroscedasticity, even after a logarithmic, and box-cox transformation. Thus, in this work we used the logarithmic transformed data to do a principal component analysis (PCA), based on the correlation matrix. The loadings of factors that at least explained one of the variables were used for a hot spot analysis, in order to identify if there was a spatial pattern in the variables distribution (Pereira et al., 2010, 2016). The results showed that in Alytus region 45.5% of the land use was classified as agricultural area, 47.3% as forest and semi-natural areas, 3.3% as water bodies, 2% as artificial surfaces and 1.9% as wetlands. The water properties of the studied lakes were the follow: pH 8.3±0.41, EC 336.31±106.49 μS/cm, 9.55±3.09 mg/l, WC 2.55±1.41 meters, BDO 3.53±1.30 mg/l, TP 0.0425±0.027 mg/l, TN 0.92±0.39 mg/l, DOC 9.61±0.79 mg/l. On average, the altitude of the lakes was 113.98±17.06 meters, MD 15.98±12.08 and lake area 243.85±386.52 ha. The PCA identified three different groups (factors). The factor 1 had high loadings in MD and WC, and high negative loadings in BDS, TP, TN and SM. The factor 2 showed high negative loadings in pH, EC and DOC. Finally, the factor 3 had high positive loadings in the area of the lake and high negative loadings in altitude. The hot spot analysis carried out with the loadings of factor 1 showed that that the area at northeast of Alytus region had a significant concentration lakes with high amounts of BDS, TP, TN, and SM, and in the west an area of lakes with high WC and MD. The hot spot analysis applied to the factor 2 loadings, showed that there was a group of lakes with high pH, EC and DOC, and a cluster located in the northeast part of Alytus region with a low level of pH, EC and DOC. Finally, the hot spot analysis applied to the factor 3 loadings, identified that the areas where the high lake area were located in the northwest of the study area, and small lakes were identified in the northeast. The lakes located at high altitude were located in the northeast area and the ones at low altitude at northeast part of Alytus area. Overall, the area with lakes with high pollution are located at northwest of the study area, where the lakes were more shallow, the altitude was low and the majority of the surroundings are covered by agricultural areas. The degradation of water quality of this area may be attributed to the fertilizers and pesticides applied by farmers in this area, contributing to the degradation of water quality and the quality of the services offered by this area. References Brevik, E., Baumgarten, A., Calzolari, C., Jordan, A., Kabala, C., Miller, B., Pereira, P. Editorial Historical perspectives and future needs in soil mapping, classification and pedological modelling, Geoderma, 264, Part B, 253-255. Pereira, P., Úbeda, X., Baltrenaite, E. (2010) Mapping Total Nitrogen in ash after a Wildfire, a microplot analysis, Ekologija, 56 (3-4), 144-152. Pereira, P., Cerdà, A., Jordán, A., Bolutiene, V., Úbeda, X., Pranskevicius, M., Mataix-Solera, J. (2013) Spatio-temporal vegetation recuperation after a grassland fire in Lithuania, Procedia Environmental Sciences, 19:856-864 Pereira, P., Gimenez-Morera, A., Novara, A., Keesstra, S., Jordan, A., Masto, R.E., Cerda, A. (2015) Soil erosion on road and railways embankments in the Canyoles river watershed, Eastern Spain, Hydrology and Earth System Sciences, Discussions, 12, 12947-12985.doi:10.5194/hessd-12-12947-2015 Pereira, P., Oliva, M., Misiune, I. (2016) Spatial interpolation of precipitation indexes in Sierra Nevada (Spain): comparing the performance of some interpolation methods, Theoretical and Applied Climatology (in press), doi:10.1007/s00704-015-1606-8

Perceptual load in different regions of the visual scene and its relevance for driving.

PubMed

Marciano, Hadas; Yeshurun, Yaffa

2015-06-01

The aim of this study was to better understand the role played by perceptual load, at both central and peripheral regions of the visual scene, in driving safety. Attention is a crucial factor in driving safety, and previous laboratory studies suggest that perceptual load is an important factor determining the efficiency of attentional selectivity. Yet, the effects of perceptual load on driving were never studied systematically. Using a driving simulator, we orthogonally manipulated the load levels at the road (central load) and its sides (peripheral load), while occasionally introducing critical events at one of these regions. Perceptual load affected driving performance at both regions of the visual scene. Critically, the effect was different for central versus peripheral load: Whereas load levels on the road mainly affected driving speed, load levels on its sides mainly affected the ability to detect critical events initiating from the roadsides. Moreover, higher levels of peripheral load impaired performance but mainly with low levels of central load, replicating findings with simple letter stimuli. Perceptual load has a considerable effect on driving, but the nature of this effect depends on the region of the visual scene at which the load is introduced. Given the observed importance of perceptual load, authors of future studies of driving safety should take it into account. Specifically, these findings suggest that our understanding of factors that may be relevant for driving safety would benefit from studying these factors under different levels of load at different regions of the visual scene. © 2014, Human Factors and Ergonomics Society.

The Cross-Cultural Validity of the MMPI-2-RF Higher-Order Scales in a Sample of North Korean Female Refugees.

PubMed

Kim, Seong-Hyeon; Goodman, Grace M; Toruno, Joseph A; Sherry, Alissa R; Kim, Hee Kyung

2015-10-01

We investigated the cross-cultural factorial validity of the three Higher-Order (H-O) scales in the Minnesota Multiphasic Personality Inventory-2 Restructured Form (MMPI-2-RF) among a sample of North Korean female refugees (N = 2,732). Given the importance of the H-O scales in the overall structure of the MMPI-2-RF scales and in interpretation, we were interested in exploring their cross-cultural validity. We conducted an exploratory factor analysis (EFA) on the nine Restructured Clinical (RC) scale raw scores and fitted and compared one- to three-factor models. The three-factor model, akin to the model in Tellegen and Ben-Porath, demonstrated the best fit to the data. Furthermore, the pattern matrices of loadings across the current sample and the U.S. samples were comparable despite some differences, such as the RC2 scale's salient, negative loading on a factor analogous to the Behavioral/Externalizing Dysfunction scale. We also investigated the unique psychological characteristics of the refugees, possibly resulting from the arduous, perilous journeys out of North Korea taken by this group of female refugees and discussed the results of EFA in light of those singular psychological traits and experiences. Overall, the three H-O scales of the Korean MMPI-2-RF evidenced reasonable cross-cultural factorial validity among the sample of North Korean female refugees. © The Author(s) 2014.

Optimize Short Term load Forcasting Anomalous Based Feed Forward Backpropagation

NASA Astrophysics Data System (ADS)

Mulyadi, Y.; Abdullah, A. G.; Rohmah, K. A.

2017-03-01

This paper contains the Short-Term Load Forecasting (STLF) using artificial neural network especially feed forward back propagation algorithm which is particularly optimized in order to getting a reduced error value result. Electrical load forecasting target is a holiday that hasn’t identical pattern and different from weekday’s pattern, in other words the pattern of holiday load is an anomalous. Under these conditions, the level of forecasting accuracy will be decrease. Hence we need a method that capable to reducing error value in anomalous load forecasting. Learning process of algorithm is supervised or controlled, then some parameters are arranged before performing computation process. Momentum constant a value is set at 0.8 which serve as a reference because it has the greatest converge tendency. Learning rate selection is made up to 2 decimal digits. In addition, hidden layer and input component are tested in several variation of number also. The test result leads to the conclusion that the number of hidden layer impact on the forecasting accuracy and test duration determined by the number of iterations when performing input data until it reaches the maximum of a parameter value.

Temporal migration patterns between natal locations of ruby-throated hummingbirds (Archilochus colubris) and their Gulf Coast stopover site.

PubMed

Zenzal, Theodore J; Contina, Andrea J; Kelly, Jeffrey F; Moore, Frank R

2018-01-01

Autumn latitudinal migrations generally exhibit one of two different temporal migration patterns: type 1 where southern populations migrate south before northern populations, or type 2 where northern populations overtake southern populations en route . The ruby-throated hummingbird ( Archilochus colubris ) is a species with an expansive breeding range, which allows opportunities to examine variation in the timing of migration. Our objective was to determine a relationship between natal origin of ruby-throated hummingbirds and arrival at a Gulf coast stopover site; and if so, what factors, such as differences in body size across the range as well as the cost of migration, might drive such a pattern. To carry out our objectives, we captured hummingbirds at a coastal stopover site during autumn migration, at which time we collected feathers from juveniles for analysis of hydrogen stable isotopes. Using the hydrogen stable isotope gradient of precipitation across North America and published hydrogen isotope values of feathers from populations of breeding ruby-throated hummingbirds, we assigned migrants to probable natal latitudes. Our results confirm that individuals from across the range (30-50° N) stopover along the Gulf of Mexico and there is a positive relationship between arrival day and latitude, suggesting a type 1 migration pattern. We also found no relationship between fuel load (proxy for migration cost) or fat-free body mass (proxy for body size) and natal latitude. Our results, coupled with previous work on the spatial migration patterns of hummingbirds, show a type 1 chain migration pattern. While the mechanisms we tested do not seem to influence the evolution of migratory patterns, other factors such as resource availability may play a prominent role in the evolution of this migration system.

Meal-specific food patterns and the incidence of hyperglycemia in a Chinese adult population.

PubMed

Shi, Zumin; Riley, Malcolm; Taylor, Anne; Noakes, Manny

2017-07-01

This study aimed to examine the association between meal-specific food patterns and incident hyperglycaemia in a Chinese adult population. Adults aged 20 years and older (n 1056) were followed from 2002 to 2007. Dietary data were collected using a 3-d food record and meal-specific (breakfast, lunch and dinner) food patterns were independently described by factor analysis based on the consumption of thirty-five food groups at each eating occasion. Each food pattern score was recoded as quartiles. Hyperglycaemia was defined as fasting plasma glucose >5·6 mmol/l at baseline and follow-up. The associated between food patterns and incident hyperglycaemia was assessed by logistic regression. During the follow-up, 125 new cases of hyperglycaemia were identified. Traditional (wheat) breakfast was inversely associated with incident hyperglycaemia, whereas traditional (rice, vegetable and pork) lunch and dinner were positively associated with the risk of incident hyperglycaemia, even after adjustment for a number of covariates including glycaemic load, carbohydrate intake and BMI. Incident hyperglycaemia occurred in 15·9, 13·6, 11·7, 6·1 % across quartiles of traditional breakfast; and 5·3, 9·1, 15·9, 17·1 % of the quartiles of traditional lunch pattern. The adjusted OR for hyperglycaemia was 0·67 (95 % CI 0·48, 0·92), 1·83 (95 % CI 1·32, 2·53) and 1·39 (95 % CI 1·04, 1·86) for 1 sd increase of traditional breakfast, lunch and dinner pattern factor score, respectively. A traditional wheat-based breakfast is associated with a decreased risk of hyperglycaemia. A rice-based traditional lunch and dinner is associated with an increased risk of hyperglycaemia in Chinese adults.

An exploratory risk perception study of attitudes toward homeland security systems.

PubMed

Sanquist, Thomas F; Mahy, Heidi; Morris, Frederic

2008-08-01

Understanding the issues surrounding public acceptance of homeland security systems is important for balancing security needs and potential civil liberties infringements. A psychometric survey was used in an exploratory study of attitudes regarding homeland security systems. Psychometric rating data were obtained from 182 respondents on psychological attributes associated with 12 distinct types of homeland security systems. An inverse relationship was observed for the overall rating attributes of acceptability and risk of civil liberties infringement. Principal components analysis (PCA) yielded a two-factor solution with the rating scale loading pattern suggesting factors of perceived effectiveness and perceived intrusiveness. These factors also showed an inverse relationship. The 12 different homeland security systems showed significantly different scores on the rating scales and PCA factors. Of the 12 systems studied, airport screening, canine detectors, and radiation monitoring at borders were found to be the most acceptable, while email monitoring, data mining, and global positioning satellite (GPS) tracking were found to be least acceptable. Students rated several systems as more effective than professionals, but the overall pattern of results for both types of subjects was similar. The data suggest that risk perception research and the psychometric paradigm are useful approaches for quantifying attitudes regarding homeland security systems and policies and can be used to anticipate potentially significant public acceptance issues.

Moving Aerospace Structural Design Practice to a Load and Resistance Factor Approach

NASA Technical Reports Server (NTRS)

Larsen, Curtis E.; Raju, Ivatury S.

2016-01-01

Aerospace structures are traditionally designed using the factor of safety (FOS) approach. The limit load on the structure is determined and the structure is then designed for FOS times the limit load - the ultimate load. Probabilistic approaches utilize distributions for loads and strengths. Failures are predicted to occur in the region of intersection of the two distributions. The load and resistance factor design (LRFD) approach judiciously combines these two approaches by intensive calibration studies on loads and strength to result in structures that are efficient and reliable. This paper discusses these three approaches.

Physiologically Distributed Loading Patterns Drive the Formation of Zonally Organized Collagen Structures in Tissue-Engineered Meniscus.

PubMed

Puetzer, Jennifer L; Bonassar, Lawrence J

2016-07-01

The meniscus is a dense fibrocartilage tissue that withstands the complex loads of the knee via a unique organization of collagen fibers. Attempts to condition engineered menisci with compression or tensile loading alone have failed to reproduce complex structure on the microscale or anatomic scale. Here we show that axial loading of anatomically shaped tissue-engineered meniscus constructs produced spatial distributions of local strain similar to those seen in the meniscus when the knee is loaded at full extension. Such loading drove formation of tissue with large organized collagen fibers, levels of mechanical anisotropy, and compressive moduli that match native tissue. Loading accelerated the development of native-sized and aligned circumferential and radial collagen fibers. These loading patterns contained both tensile and compressive components that enhanced the major biochemical and functional properties of the meniscus, with loading significantly improved glycosaminoglycan (GAG) accumulation 200-250%, collagen accumulation 40-55%, equilibrium modulus 1000-1800%, and tensile moduli 500-1200% (radial and circumferential). Furthermore, this study demonstrates local changes in mechanical environment drive heterogeneous tissue development and organization within individual constructs, highlighting the importance of recapitulating native loading environments. Loaded menisci developed cartilage-like tissue with rounded cells, a dense collagen matrix, and increased GAG accumulation in the more compressively loaded horns, and fibrous collagen-rich tissue in the more tensile loaded outer 2/3, similar to native menisci. Loaded constructs reached a level of organization not seen in any previous engineered menisci and demonstrate great promise as meniscal replacements.

Regional effects of agricultural conservation practices on nutrient transport in the Upper Mississippi River Basin

USGS Publications Warehouse

Garcia, Ana Maria.; Alexander, Richard B.; Arnold, Jeffrey G.; Norfleet, Lee; White, Michael J.; Robertson, Dale M.; Schwarz, Gregory E.

2016-01-01

Despite progress in the implementation of conservation practices, related improvements in water quality have been challenging to measure in larger river systems. In this paper we quantify these downstream effects by applying the empirical U.S. Geological Survey water-quality model SPARROW to investigate whether spatial differences in conservation intensity were statistically correlated with variations in nutrient loads. In contrast to other forms of water quality data analysis, the application of SPARROW controls for confounding factors such as hydrologic variability, multiple sources and environmental processes. A measure of conservation intensity was derived from the USDA-CEAP regional assessment of the Upper Mississippi River and used as an explanatory variable in a model of the Upper Midwest. The spatial pattern of conservation intensity was negatively correlated (p = 0.003) with the total nitrogen loads in streams in the basin. Total phosphorus loads were weakly negatively correlated with conservation (p = 0.25). Regional nitrogen reductions were estimated to range from 5 to 34% and phosphorus reductions from 1 to 10% in major river basins of the Upper Mississippi region. The statistical associations between conservation and nutrient loads are consistent with hydrological and biogeochemical processes such as denitrification. The results provide empirical evidence at the regional scale that conservation practices have had a larger statistically detectable effect on nitrogen than on phosphorus loadings in streams and rivers of the Upper Mississippi Basin.

Regional Effects of Agricultural Conservation Practices on Nutrient Transport in the Upper Mississippi River Basin.

PubMed

García, Ana María; Alexander, Richard B; Arnold, Jeffrey G; Norfleet, Lee; White, Michael J; Robertson, Dale M; Schwarz, Gregory

2016-07-05

Despite progress in the implementation of conservation practices, related improvements in water quality have been challenging to measure in larger river systems. In this paper we quantify these downstream effects by applying the empirical U.S. Geological Survey water-quality model SPARROW to investigate whether spatial differences in conservation intensity were statistically correlated with variations in nutrient loads. In contrast to other forms of water quality data analysis, the application of SPARROW controls for confounding factors such as hydrologic variability, multiple sources and environmental processes. A measure of conservation intensity was derived from the USDA-CEAP regional assessment of the Upper Mississippi River and used as an explanatory variable in a model of the Upper Midwest. The spatial pattern of conservation intensity was negatively correlated (p = 0.003) with the total nitrogen loads in streams in the basin. Total phosphorus loads were weakly negatively correlated with conservation (p = 0.25). Regional nitrogen reductions were estimated to range from 5 to 34% and phosphorus reductions from 1 to 10% in major river basins of the Upper Mississippi region. The statistical associations between conservation and nutrient loads are consistent with hydrological and biogeochemical processes such as denitrification. The results provide empirical evidence at the regional scale that conservation practices have had a larger statistically detectable effect on nitrogen than on phosphorus loadings in streams and rivers of the Upper Mississippi Basin.

Measuring cognitive load during procedural skills training with colonoscopy as an exemplar.

PubMed

Sewell, Justin L; Boscardin, Christy K; Young, John Q; Ten Cate, Olle; O'Sullivan, Patricia S

2016-06-01

Few studies have investigated cognitive factors affecting learning of procedural skills in medical education. Cognitive load theory, which focuses on working memory, is highly relevant, but methods for measuring cognitive load during procedural training are not well understood. Using colonoscopy as an exemplar, we used cognitive load theory to develop a self-report instrument to measure three types of cognitive load (intrinsic, extraneous and germane load) and to provide evidence for instrument validity. We developed the instrument (the Cognitive Load Inventory for Colonoscopy [CLIC]) using a multi-step process. It included 19 items measuring three types of cognitive load, three global rating items and demographics. We then conducted a cross-sectional survey that was administered electronically to 1061 gastroenterology trainees in the USA. Participants completed the CLIC following a colonoscopy. The two study phases (exploratory and confirmatory) each lasted for 10 weeks during the 2014-2015 academic year. Exploratory factor analysis determined the most parsimonious factor structure; confirmatory factor analysis assessed model fit. Composite measures of intrinsic, extraneous and germane load were compared across years of training and with global rating items. A total of 477 (45.0%) invitees participated (116 in the exploratory study and 361 in the confirmatory study) in 154 (95.1%) training programmes. Demographics were similar to national data from the USA. The most parsimonious factor structure included three factors reflecting the three types of cognitive load. Confirmatory factor analysis verified that a three-factor model was the best fit. Intrinsic, extraneous and germane load items had high internal consistency (Cronbach's alpha 0.90, 0.87 and 0.96, respectively) and correlated as expected with year in training and global assessment of cognitive load. The CLIC measures three types of cognitive load during colonoscopy training. Evidence of validity is provided. Although CLIC items relate to colonoscopy, the development process we detail can be used to adapt the instrument for use in other learning settings in medical education. © 2016 John Wiley & Sons Ltd.

Dietary patterns in Swedish adults; results from a national dietary survey.

PubMed

Ax, Erika; Warensjö Lemming, Eva; Becker, Wulf; Andersson, Agneta; Lindroos, Anna Karin; Cederholm, Tommy; Sjögren, Per; Fung, Teresa T

2016-01-14

Dietary patterns derived by statistical procedures is a way to identify overall dietary habits in specific populations. The aim of this study was to identify and characterise dietary patterns in Swedish adults using data from the national dietary survey Riksmaten adults 2010-11 (952 women, 788 men). Principal component analyses were used and two patterns were identified in both sexes: a healthy pattern loading positively on vegetables, fruits, fish and seafood, and vegetable oils, and negatively on refined bread and fast food, and a Swedish traditional pattern loading positively on potatoes, meat and processed meat, full-fat milk products, sweet bakery products, sweet condiments and margarine. In addition, a light-meal pattern was identified in women with positive loadings on fibre-rich bread, cheese, rice, pasta and food grain dishes, substitute products for meat and dairy products, candies and tea. The healthy pattern was positively correlated to dietary fibre (r 0·51-0·58) and n-3 (r 0·25-0·31) (all P<0·0001), and had a higher nutrient density of folate, vitamin D and Se. The Swedish traditional and the light-meal pattern were positively correlated to added sugar (r 0·20-0·25) and the Swedish traditional also to SFA (r 0·13-0·21) (all P<0·0001); both patterns were in general negatively correlated to micronutrients. Dietary pattern scores were associated with, for example, age, physical activity, education and income. In conclusion, we identified three major dietary patterns among Swedish adults. The patterns can be further used for examining the association between whole diet and health outcomes.

Patterns of interactions at grade 5 classroom in learning the topic of statistics viewed from cognitive load theory

NASA Astrophysics Data System (ADS)

Setianingsih, R.

2018-01-01

The nature of interactions that occurs among teacher, students, learning sources, and learning environment creates different settings to enhance learning. Any setting created by a teacher is affected by 3 (three) types of cognitive load: intrinsic cognitive load, extraneous cognitive load, and germane cognitive load. This study is qualitative in nature, aims to analyse the patterns of interaction that are constituted in mathematics instructions by taking into account the cognitive load theory. The subjects of this study are 21 fifth-grade students who learn mathematics in small groups and whole-class interactive lessons. The data were collected through classroom observations which were videotaped, while field notes were also taken. The data analysis revealed that students engaged in productive interaction and inquiry while they were learning mathematics in small groups or in whole class setting, in which there was a different type of cognitive load that dominantly affecting the learning processes at each setting. During learning mathematics in whole class setting, the most frequently found interaction patterns were to discuss and compare solution based on self-developed models, followed by expressing opinions. This is consistent with the principles of mathematics learning, which gives students wide opportunities to construct mathematical knowledge through individual learning, learning in small groups as well as learning in whole class settings. It means that by participating in interactive learning, the students are habitually engaged in productive interactions and high level of mathematical thinking.

Gene-Diet Interactions in Type 2 Diabetes: The Chicken and Egg Debate

PubMed Central

Ortega, Ángeles; Berná, Genoveva; Rojas, Anabel; Martín, Franz; Soria, Bernat

2017-01-01

Consistent evidence from both experimental and human studies indicates that Type 2 diabetes mellitus (T2DM) is a complex disease resulting from the interaction of genetic, epigenetic, environmental, and lifestyle factors. Nutrients and dietary patterns are important environmental factors to consider in the prevention, development and treatment of this disease. Nutritional genomics focuses on the interaction between bioactive food components and the genome and includes studies of nutrigenetics, nutrigenomics and epigenetic modifications caused by nutrients. There is evidence supporting the existence of nutrient-gene and T2DM interactions coming from animal studies and family-based intervention studies. Moreover, many case-control, cohort, cross-sectional cohort studies and clinical trials have identified relationships between individual genetic load, diet and T2DM. Some of these studies were on a large scale. In addition, studies with animal models and human observational studies, in different countries over periods of time, support a causative relationship between adverse nutritional conditions during in utero development, persistent epigenetic changes and T2DM. This review provides comprehensive information on the current state of nutrient-gene interactions and their role in T2DM pathogenesis, the relationship between individual genetic load and diet, and the importance of epigenetic factors in influencing gene expression and defining the individual risk of T2DM. PMID:28574454

Motor control goes beyond physics: differential effects of gravity and inertia on finger forces during manipulation of hand-held objects.

PubMed

Zatsiorsky, Vladimir M; Gao, Fan; Latash, Mark L

2005-04-01

According to basic physics, the local effects induced by gravity and acceleration are identical and cannot be separated by any physical experiment. In contrast-as this study shows-people adjust the grip forces associated with gravitational and inertial forces differently. In the experiment, subjects oscillated a vertically-oriented handle loaded with five different weights (from 3.8 N to 13.8 N) at three different frequencies in the vertical plane: 1 Hz, 1.5 Hz and 2.0 Hz. Three contributions to the grip force-static, dynamic, and stato-dynamic fractions-were quantified. The static fraction reflects grip force related to holding a load statically. The stato-dynamic fraction reflects a steady change in the grip force when the same load is moved cyclically. The dynamic fraction is due to acceleration-related adjustments of the grip force during oscillation cycles. The slope of the relation between the grip force and the load force was steeper for the static fraction than for the dynamic fraction. The stato-dynamic fraction increased with the frequency and load. The slope of the dynamic grip force-load force relation decreased with frequency, and as a rule, increased with the load. Hence, when adjusting grip force to task requirements, the central controller takes into account not only the expected magnitude of the load force but also such factors as whether the force is gravitational or inertial and the contributions of the object mass and acceleration to the inertial force. As an auxiliary finding, a complex finger coordination pattern aimed at preserving the rotational equilibrium of the object during shaking movements was reported.

Near-infrared mediated quantum dots and paclitaxel co-loaded nanostructured lipid carriers for cancer theragnostic.

PubMed

Olerile, Livesey David; Liu, Yongjun; Zhang, Bo; Wang, Tianqi; Mu, Shengjun; Zhang, Jing; Selotlegeng, Lesego; Zhang, Na

2017-02-01

Timing is an important factor in cancer management. Theragnostic systems have benefit of improving patients' life-quality by expediting therapeutic decisions. The objective of this study was to explore the potential of co-loaded [quantum dots (CdTe/CdS/ZnS) and paclitaxel] NLC (nanostructured lipid carriers) as a parenteral multifunctional delivery system. The co-loaded NLC was prepared by emulsion-evaporation and low temperature-solidification method utilising glyceryl monostearate, oleic acid, and soya phosphatidylcholine as lipid matrix. In characterising the co-loaded NLC, physicochemical properties of particle size, polydispersity index (PDI), zeta potential (ZP), morphology, encapsulation efficacy (EE) and drug loading (DL) were investigated. Moreover, in-vitro paclitaxel release profile, cytotoxicity, histopathological, in-vivo anti-tumour efficacy, and in-vivo and ex-vivo fluorescence optical imaging abilities of the co-loaded NLC were assessed. The mean particle size, PDI and ZP were reported to be 115.93±1.61nm, 0.17±0.04 and -0.22±0.03mV, respectively. The particles were spheroid-like in shape with relatively smooth surface. A higher EE (80.70±2.11%) and DL (4.68±0.04%) were recorded. The coloaded NLC exhibited a biphasic pattern of drug release. IC 50 value was found to be 1.05±0.58μM. The tumour growth inhibition rate of 77.85% was registered. The in-vivo and ex-vivo imaging results indicated capability of the co-loaded NLC to specifically target and detect the H22 tumour. Tissues showed no significant cytoarchitectural differences. We can satisfactorily conclude that co-loaded NLC formulation can be qualified as a splendid parenteral drug delivery system foundation for cancer theragnostic. Copyright © 2016 Elsevier B.V. All rights reserved.

Patterns of circulating fat-soluble vitamins and carotenoids and risk of frailty in four European cohorts of older adults.

PubMed

Pilleron, Sophie; Weber, Daniela; Pérès, Karine; Colpo, Marco; Gomez-Cabrero, David; Stuetz, Wolfgang; Dartigues, Jean-François; Ferrucci, Luigi; Bandinelli, Stefania; Garcia-Garcia, Francisco Jose; Grune, Tilman; Féart, Catherine

2018-01-27

To investigate the cross-sectional and prospective associations between patterns of serum fat-soluble micronutrients and frailty in four European cohorts of older adults 65 years of age and older. Participants from the Three-City (Bordeaux, France), AMI (Gironde, France), TSHA (Toledo, Spain) and InCHIANTI (Tuscany, Italy) cohorts with available data on serum α-carotene, β-carotene, lycopene, cryptoxanthin, lutein + zeaxanthin, retinol, α-tocopherol, γ-tocopherol and 25-hydroxyvitamin D3 (25(OH)D) were included. A principal component (PC) analysis was used to derive micronutrient patterns. Frailty was defined using Fried's criteria. Multivariate logistic regression models adjusted for socio-demographic and health-related covariates were performed to assess the association between micronutrient patterns and prevalent frailty in 1324 participants, and the risk of frailty in 915 initially non-frail participants. Three different patterns were identified: the first pattern was characterized by higher serum carotenoids and α-tocopherol levels; the second was characterized by high loadings for serum vitamins A and E levels and low loadings for carotenes level; the third one had the highest loading for serum 25(OH)D and cryptoxanthin level and the lowest loading for vitamin A and E. A significant cross-sectional association was only observed between the seconnd PC and prevalent frailty (p = 0.02). Compared to the highest quartile, participants in the lowest quartile-i.e., high carotenes and low vitamins E and A levels-had higher odds of frailty (Odds ratio = 2.2; 95% confidence interval 1.3-3.8). No association with the risk of frailty was observed. These findings suggest that some specific micronutrient patterns are markers but not predictors of frailty in these European cohorts of older adults.

Aerosol loading impact on Asian monsoon precipitation patterns

NASA Astrophysics Data System (ADS)

Biondi, Riccardo; Cagnazzo, Chiara; Costabile, Francesca; Cairo, Francesco

2017-04-01

Solar light absorption by aerosols such as black carbon and dust assume a key role in driving the precipitation patterns in the Indian subcontinent. The aerosols stack up against the foothills of the Himalayas in the pre-monsoon season and several studies have already demonstrated that this can cause precipitation anomalies during summer. Despite its great significance in climate change studies, the link between absorbing aerosols loading and precipitation patterns remains highly uncertain. The main challenge for this kind of studies is to find consistent and reliable datasets. Several aerosol time series are available from satellite and ground based instruments and some precipitation datasets from satellite sensors, but they all have different time/spatial resolution and they use different assumptions for estimating the parameter of interest. We have used the aerosol estimations from the Ozone Monitoring Instrument (OMI), the Along-Track Scanning Radiometer (AATSR) and the MODerate resolution Imaging Spectroradiometer (MODIS) and validated them against the Aerosol Robotic Network (AERONET) measurements in the Indian area. The precipitation has been analyzed by using the Tropical Rainfall Measuring Mission (TRMM) estimations and the Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2). From our results it is evident the discrepancy between the aerosol loading on the area of interest from the OMI, AATSR, and MODIS, but even between 3 different algorithms applied to the MODIS data. This uncertainty does not allow to clearly distinguishing high aerosol loading years from low aerosol loading years except in a couple of cases where all the estimations agree. Similar issues are also present in the precipitation estimations from TRMM and MERRA-2. However, all the aerosol datasets agree in defining couples of consecutive years with a large gradient of aerosol loading. Based on this assumption we have compared the precipitation anomalies and found typical patterns characterizing different Indian regions in late summer. Analyzing the AERONET data we have also separated the black carbon and dust contribution to the total aerosol loading based on aerosol spectral optical properties for investigating the link between different aerosol types and precipitation patterns.

Universal resilience patterns in cascading load model: More capacity is not always better

NASA Astrophysics Data System (ADS)

Wang, Jianwei; Wang, Xue; Cai, Lin; Ni, Chengzhang; Xie, Wei; Xu, Bo

We study the problem of universal resilience patterns in complex networks against cascading failures. We revise the classical betweenness method and overcome its limitation of quantifying the load in cascading model. Considering that the generated load by all nodes should be equal to the transported one by all edges in the whole network, we propose a new method to quantify the load on an edge and construct a simple cascading model. By attacking the edge with the highest load, we show that, if the flow between two nodes is transported along the shortest paths between them, then the resilience of some networks against cascading failures inversely decreases with the enhancement of the capacity of every edge, i.e. the more capacity is not always better. We also observe the abnormal fluctuation of the additional load that exceeds the capacity of each edge. By a simple graph, we analyze the propagation of cascading failures step by step, and give a reasonable explanation of the abnormal fluctuation of cascading dynamics.

Condition factor calibration for load and resistance factor rating of steel girder bridges : final report.

DOT National Transportation Integrated Search

2016-06-01

Load and Resistance Factor Rating (LRFR) is a reliability-based rating procedure complementary to Load and Resistance Factor Design (LRFD). The intent of LRFR is to provide consistent reliability for all bridges regardless of in-situ condition. The p...

Structural differences within negative and depressive syndrome dimensions in schizophrenia, organic brain disease, and major depression: A confirmatory factor analysis of the positive and negative syndrome scale.

PubMed

Eisenberg, Daniel P; Aniskin, Dmitry B; White, Leonard; Stein, Judith A; Harvey, Philip D; Galynker, Igor I

2009-01-01

The emerging dimensional approach to classification and treatment of psychiatric disorders calls for better understanding of diagnosis-related variations in psychiatric syndromes and for proper validation of psychometric scales used for the evaluation of those syndromes. This study tested the hypothesis that negative and depressive syndromes as measured by the Positive and Negative Syndrome Scale (PANSS) are consistent across different diagnoses. We administered the PANSS to subjects with schizophrenia (n = 305), organic brain disease (OBD, n = 66) and major depressive disorder (MDD, n = 75). Confirmatory factor analysis (CFA) was used to establish if the PANSS items for negative symptoms and for depression fit the hypothesized factor structure and if the item factor loadings were similar among the diagnostic groups. The negative and depressive symptom subscales fit well according to a variety of fit indexes for all groups individually after some modest model modification. However, multisample modeling procedures indicated that the pattern of factor loadings was significantly different among the groups in most cases. The results of this study indicate diagnosis-related variations in the negative and depressive syndrome dimensions in schizophrenia, OBD and MDD. These results also validate limited use of the PANSS for evaluation of negative and depressive syndromes in disorders other than schizophrenia. Larger studies are warranted to further evaluate clinical and nosologic significance of diagnostic categories, dimensions and structures of psychiatric syndromes. 2009 S. Karger AG, Basel.

14 CFR 23.525 - Application of loads.

Code of Federal Regulations, 2012 CFR

2012-01-01

... the loads corresponding to the load factors specified in § 23.527. (b) In applying the loads resulting from the load factors prescribed in § 23.527, the loads may be distributed over the hull or main float... on the seaplane during the impact is assumed to be 2/3 of the weight of the seaplane. [Doc. No. 26269...

14 CFR 23.525 - Application of loads.

Code of Federal Regulations, 2013 CFR

2013-01-01

... the loads corresponding to the load factors specified in § 23.527. (b) In applying the loads resulting from the load factors prescribed in § 23.527, the loads may be distributed over the hull or main float... on the seaplane during the impact is assumed to be 2/3 of the weight of the seaplane. [Doc. No. 26269...

14 CFR 23.525 - Application of loads.

Code of Federal Regulations, 2010 CFR

2010-01-01

... the loads corresponding to the load factors specified in § 23.527. (b) In applying the loads resulting from the load factors prescribed in § 23.527, the loads may be distributed over the hull or main float... on the seaplane during the impact is assumed to be 2/3 of the weight of the seaplane. [Doc. No. 26269...

14 CFR 23.525 - Application of loads.

Code of Federal Regulations, 2014 CFR

2014-01-01

... the loads corresponding to the load factors specified in § 23.527. (b) In applying the loads resulting from the load factors prescribed in § 23.527, the loads may be distributed over the hull or main float... on the seaplane during the impact is assumed to be 2/3 of the weight of the seaplane. [Doc. No. 26269...

Femoral loading mechanics in the Virginia opossum, Didelphis virginiana: torsion and mediolateral bending in mammalian locomotion.

PubMed

Gosnell, W Casey; Butcher, Michael T; Maie, Takashi; Blob, Richard W

2011-10-15

Studies of limb bone loading in terrestrial mammals have typically found anteroposterior bending to be the primary loading regime, with torsion contributing minimally. However, previous studies have focused on large, cursorial eutherian species in which the limbs are held essentially upright. Recent in vivo strain data from the Virginia opossum (Didelphis virginiana), a marsupial that uses a crouched rather than an upright limb posture, have indicated that its femur experiences appreciable torsion during locomotion as well as strong mediolateral bending. The elevated femoral torsion and strong mediolateral bending observed in D. virginiana might result from external forces such as a medial inclination of the ground reaction force (GRF), internal forces deriving from a crouched limb posture, or a combination of these factors. To evaluate the mechanism underlying the loading regime of opossum femora, we filmed D. virginiana running over a force platform, allowing us to measure the magnitude of the GRF and its three-dimensional orientation relative to the limb, facilitating estimates of limb bone stresses. This three-dimensional analysis also allows evaluations of muscular forces, particularly those of hip adductor muscles, in the appropriate anatomical plane to a greater degree than previous two-dimensional analyses. At peak GRF and stress magnitudes, the GRF is oriented nearly vertically, inducing a strong abductor moment at the hip that is countered by adductor muscles on the medial aspect of the femur that place this surface in compression and induce mediolateral bending, corroborating and explaining loading patterns that were identified in strain analyses. The crouched orientation of the femur during stance in opossums also contributes to levels of femoral torsion as high as those seen in many reptilian taxa. Femoral safety factors were as high as those of non-avian reptiles and greater than those of upright, cursorial mammals, primarily because the load magnitudes experienced by opossums are lower than those of most mammals. Thus, the evolutionary transition from crouched to upright posture in mammalian ancestors may have been accompanied by an increase in limb bone load magnitudes.

Risk Factors for Knee Injury in Golf: A Systematic Review.

PubMed

Baker, Matthew L; Epari, Devakar R; Lorenzetti, Silvio; Sayers, Mark; Boutellier, Urs; Taylor, William R

2017-12-01

Golf is commonly considered a low-impact sport that carries little risk of injury to the knee and is generally allowed following total knee arthroplasty (TKA). Kinematic and kinetic studies of the golf swing have reported results relevant to the knee, but consensus as to the loads experienced during a swing and how the biomechanics of an individual's technique may expose the knee to risk of injury is lacking. Our objective was to establish (1) the prevalence of knee injury resulting from participation in golf and (2) the risk factors for knee injury from a biomechanical perspective, based on an improved understanding of the internal loading conditions and kinematics that occur in the knee from the time of addressing the ball to the end of the follow-through. A systematic literature search was conducted to determine the injury rate, kinematic patterns, loading, and muscle activity of the knee during golf. A knee injury prevalence of 3-18% was established among both professional and amateur players, with no clear dependence on skill level or sex; however, older players appear at greater risk of injury. Studies reporting kinematics indicate that the lead knee is exposed to a complex series of motions involving rapid extension and large magnitudes of tibial internal rotation, conditions that may pose risks to the structures of a natural knee or TKA. To date, the loads experienced by the lead knee during a golf swing have been reported inconsistently in the literature. Compressive loads ranging from 100 to 440% bodyweight have been calculated and measured using methods including inverse dynamics analysis and instrumented knee implants. Additionally, the magnitude of loading appears to be independent of the club used. This review is the first to highlight the lack of consensus regarding knee loading during the golf swing and the associated risks of injury. Results from the literature suggest the lead knee is subject to a higher magnitude of stress and more demanding motions than the trail knee. Therefore, recommendations regarding return to golf following knee injury or surgical intervention should carefully consider the laterality of the injury.

14 CFR 23.507 - Jacking loads.

Code of Federal Regulations, 2013 CFR

2013-01-01

...) Vertical-load factor of 1.35 times the static reactions. (2) Fore, aft, and lateral load factors of 0.4 times the vertical static reactions. (b) The horizontal loads at the jack points must be reacted by...

14 CFR 23.507 - Jacking loads.

Code of Federal Regulations, 2010 CFR

2010-01-01

...) Vertical-load factor of 1.35 times the static reactions. (2) Fore, aft, and lateral load factors of 0.4 times the vertical static reactions. (b) The horizontal loads at the jack points must be reacted by...

14 CFR 23.507 - Jacking loads.

Code of Federal Regulations, 2012 CFR

2012-01-01

...) Vertical-load factor of 1.35 times the static reactions. (2) Fore, aft, and lateral load factors of 0.4 times the vertical static reactions. (b) The horizontal loads at the jack points must be reacted by...

14 CFR 23.507 - Jacking loads.

Code of Federal Regulations, 2011 CFR

2011-01-01

...) Vertical-load factor of 1.35 times the static reactions. (2) Fore, aft, and lateral load factors of 0.4 times the vertical static reactions. (b) The horizontal loads at the jack points must be reacted by...

The Importance of Splat Events to the Spatiotemporal Structure of Near-Bed Fluid Velocity and Bed Load Motion Over Bed Forms: Laboratory Experiments Downstream of a Backward Facing Step

NASA Astrophysics Data System (ADS)

Leary, K. C. P.; Schmeeckle, M. W.

2017-12-01

Flow separation/reattachment on the lee side of alluvial bed forms is known to produce a complex turbulence field, but the spatiotemporal details of the associated patterns of bed load sediment transported remain largely unknown. Here we report turbulence-resolving, simultaneous measurements of bed load motion and near-bed fluid velocity downstream of a backward facing step in a laboratory flume. Two synchronized high-speed video cameras simultaneously observed bed load motion and the motion of neutrally buoyant particles in a laser light sheet 6 mm above the bed at 250 frames/s downstream of a 3.8 cm backward facing step. Particle Imaging Velocimetry (PIV) and Acoustic Doppler Velocimetry (ADV) were used to characterize fluid turbulent patterns, while manual particle tracking techniques were used to characterize bed load transport. Octant analysis, conducted using ADV data, coupled with Markovian sequence probability analysis highlights differences in the flow near reattachment versus farther downstream. Near reattachment, three distinct flow patterns are apparent. Farther downstream we see the development of a dominant flow sequence. Localized, intermittent, high-magnitude transport events are more apparent near flow reattachment. These events are composed of streamwise and cross-stream fluxes of comparable magnitudes. Transport pattern and fluid velocity data are consistent with the existence of permeable "splat events," wherein a volume of fluid moves toward and impinges on the bed (sweep) causing a radial movement of fluid in all directions around the point of impingement (outward interaction). This is congruent with flow patterns, identified with octant analysis, proximal to flow reattachment.

Using a latent variable model with non-constant factor loadings to examine PM2.5 constituents related to secondary inorganic aerosols.

PubMed

Zhang, Zhenzhen; O'Neill, Marie S; Sánchez, Brisa N

2016-04-01

Factor analysis is a commonly used method of modelling correlated multivariate exposure data. Typically, the measurement model is assumed to have constant factor loadings. However, from our preliminary analyses of the Environmental Protection Agency's (EPA's) PM 2.5 fine speciation data, we have observed that the factor loadings for four constituents change considerably in stratified analyses. Since invariance of factor loadings is a prerequisite for valid comparison of the underlying latent variables, we propose a factor model that includes non-constant factor loadings that change over time and space using P-spline penalized with the generalized cross-validation (GCV) criterion. The model is implemented using the Expectation-Maximization (EM) algorithm and we select the multiple spline smoothing parameters by minimizing the GCV criterion with Newton's method during each iteration of the EM algorithm. The algorithm is applied to a one-factor model that includes four constituents. Through bootstrap confidence bands, we find that the factor loading for total nitrate changes across seasons and geographic regions.

Parameter Accuracy in Meta-Analyses of Factor Structures

ERIC Educational Resources Information Center

Gnambs, Timo; Staufenbiel, Thomas

2016-01-01

Two new methods for the meta-analysis of factor loadings are introduced and evaluated by Monte Carlo simulations. The direct method pools each factor loading individually, whereas the indirect method synthesizes correlation matrices reproduced from factor loadings. The results of the two simulations demonstrated that the accuracy of…

The Effect of an Extreme and Prolonged Population Bottleneck on Patterns of Deleterious Variation: Insights from the Greenlandic Inuit.

PubMed

Pedersen, Casper-Emil T; Lohmueller, Kirk E; Grarup, Niels; Bjerregaard, Peter; Hansen, Torben; Siegismund, Hans R; Moltke, Ida; Albrechtsen, Anders

2017-02-01

The genetic consequences of population bottlenecks on patterns of deleterious genetic variation in human populations are of tremendous interest. Based on exome sequencing of 18 Greenlandic Inuit we show that the Inuit have undergone a severe ∼20,000-year-long bottleneck. This has led to a markedly more extreme distribution of allele frequencies than seen for any other human population tested to date, making the Inuit the perfect population for investigating the effect of a bottleneck on patterns of deleterious variation. When comparing proxies for genetic load that assume an additive effect of deleterious alleles, the Inuit show, at most, a slight increase in load compared to European, East Asian, and African populations. Specifically, we observe <4% increase in the number of derived deleterious alleles in the Inuit. In contrast, proxies for genetic load under a recessive model suggest that the Inuit have a significantly higher load (20% increase or more) compared to other less bottlenecked human populations. Forward simulations under realistic models of demography support our empirical findings, showing up to a 6% increase in the genetic load for the Inuit population across all models of dominance. Further, the Inuit population carries fewer deleterious variants than other human populations, but those that are present tend to be at higher frequency than in other populations. Overall, our results show how recent demographic history has affected patterns of deleterious variants in human populations. Copyright © 2017 by the Genetics Society of America.

Gait asymmetries in unilateral symptomatic hip osteoarthritis and their association with radiographic severity and pain.

PubMed

Farkas, Gary J; Schlink, Bryan R; Fogg, Louis F; Foucher, Kharma C; Wimmer, Markus A; Shakoor, Najia

2018-05-01

Little is known about the loading patterns in unilateral hip osteoarthritis (OA) and their relationship to radiographic severity and pain. We aimed to examine the loading patterns at the hips of those with unilateral symptomatic hip OA and identify associations between radiographic severity and pain with loading alterations. Sixty-one subjects with symptomatic unilateral hip OA underwent gait analyses and evaluation for radiographic severity (Kellgren-Lawrence [KL]-grade) and pain (visual analogue scale) at bilateral hips. Hip OA subjects had greater range of motion and higher hip flexion, adduction, internal and external rotation moments at the contralateral, asymptomatic hip compared to the ipsilateral hip ( p < 0.05). Correlations were noted between increasing KL-grade and increasing asymmetry of contralateral to ipsilateral hip loading ( p < 0.05). There were no relationships with pain and loading asymmetry. Unilateral symptomatic hip OA subjects demonstrate asymmetry in loading between the hips, with relatively greater loads at the contralateral hip. These loading asymmetries were directly related to the radiographic severity of symptomatic hip OA and not with pain. Additional research is needed to determine the role of gait asymmetries in disease progression.

The transfer of movement sequences: effects of decreased and increased load.

PubMed

Muehlbauer, Thomas; Panzer, Stefan; Shea, Charles H

2007-06-01

A number of recent experiments have demonstrated that a movement structure develops during the course of learning a movement sequence that provides the basis for transfer. After learning a movement sequence participants have been shown to be able to effectively produce the sequence when movement demands require that the sequence be rescaled in amplitude or produced with an unpractised set of effectors. The purpose of the present experiment was to determine whether participants, after learning a complex 16-element movement sequence with a 0.567-kg load, could also effectively produce the sequence when the load was decreased (0.0 kg) or increased (1.134 kg). The results indicated that participants were able to effectively compensate for decreased and increased load with virtually no changes in performance characteristics (displacement, velocity, acceleration, and pattern of element durations) while electromyographic (EMG) signals demonstrated that smaller (reduced load) or larger forces (increased load) were spontaneously generated to compensate for the change in load. The muscle activation patterns of the biceps and triceps as well as the level of coactivation appeared to be generally upscaled to generate and dissipate the changes in force requirement needed to compensate for the increased load.

Synthesis of resistive tapers to control scattering patterns of strips

NASA Astrophysics Data System (ADS)

Haupt, Randy L.

Scattering occurs when an electromagnetic wave impinges on an object and creates currents in that object which reradiate other electromagnetic waves. Three primary methods exist to reduce microwave scattering from an object: covering it with absorber, changing its shape, and detuning it through impedance loading. Absorbers convert unwanted electromagnetic energy into heat. An example is lining an anechoic chamber with absorbers. Changing its shape channels energy from one direction to another, changes dominant scattering centers, or causes returns from one direction to another, changes dominant scattering centers, or causes returns from various parts to coherently add and cancel the total return. Impedance loading alters the resonant frequency of an object. Absorbers have the most attractive features. They have a broad bandwidth, attenuate the return in many directions, and may be used to reduce scattering from an object after the object is designed. Before trying to control scattering from complex shapes, such as an antenna or airplane, one should try to develop methods to control scattering from simple objects. A very simple object is two dimensional strip. It is infinitely thin, has a finite width, and an infinite length. The scattering pattern of the strip depends upon its width and material composition. Varying these two factors provides a means for controlling the radar cross-section (RCS) of the strip. The goal of this thesis is to synthesize resistive tapers for the strip that produce desired bistatic scattering and backscattering patterns.

Injuries And Footwear (Part 2): Minimalist Running Shoes.

PubMed

Knapik, Joseph J; Orr, Robin; Pope, Rodney; Grier, Tyson

2016-01-01

This article defines minimalist running shoes and examines physiological, biomechanical, and injury rate differences when running in conventional versus minimalist running shoes. A minimalist shoe is one that provides "minimal interference with the natural movement of the foot, because of its high flexibility, low heel to toe drop, weight and stack height, and the absence of motion control and stability devices." Most studies indicate that running in minimalist shoes results in a lower physiological energy cost than running in conventional shoes, likely because of the lower weight of the minimalist shoe. Most individuals running in conventional shoes impact the ground heel first (rearfoot strike pattern), whereas most people running in minimalist shoes tend to strike with the front of the foot (forefoot strike pattern). The rate at which force is developed on ground impact (i.e., the loading rate) is generally higher when running in conventional versus minimalist shoes. Findings from studies that have looked at associations between injuries and foot strike patterns or injuries and loading rates are conflicting, so it is not clear if these factors influence injury rates; more research is needed. Better-designed prospective studies indicate that bone stress injuries and the overall injury incidence are higher in minimalist shoes during the early weeks (10-12 weeks) of transition to this type of footwear. Longer-term studies are needed to define injury rates once runners are fully transitioned to minimalist shoes. At least one longer-term minimalist-shoe investigation is ongoing and, hopefully, will be published soon. 2016.

Comparison of Two Parametric Methods to Estimate Pesticide Mass Loads in California's Central Valley

USGS Publications Warehouse

Saleh, D.K.; Lorenz, D.L.; Domagalski, Joseph L.

2011-01-01

Mass loadings were calculated for four pesticides in two watersheds with different land uses in the Central Valley, California, by using two parametric models: (1) the Seasonal Wave model (SeaWave), in which a pulse signal is used to describe the annual cycle of pesticide occurrence in a stream, and (2) the Sine Wave model, in which first-order Fourier series sine and cosine terms are used to simulate seasonal mass loading patterns. The models were applied to data collected during water years 1997 through 2005. The pesticides modeled were carbaryl, diazinon, metolachlor, and molinate. Results from the two models show that the ability to capture seasonal variations in pesticide concentrations was affected by pesticide use patterns and the methods by which pesticides are transported to streams. Estimated seasonal loads compared well with results from previous studies for both models. Loads estimated by the two models did not differ significantly from each other, with the exceptions of carbaryl and molinate during the precipitation season, where loads were affected by application patterns and rainfall. However, in watersheds with variable and intermittent pesticide applications, the SeaWave model is more suitable for use on the basis of its robust capability of describing seasonal variation of pesticide concentrations. ?? 2010 American Water Resources Association. This article is a US Government work and is in the public domain in the USA.

Estimating Escherichia coli loads in streams based on various physical, chemical, and biological factors

PubMed Central

Dwivedi, Dipankar; Mohanty, Binayak P.; Lesikar, Bruce J.

2013-01-01

Microbes have been identified as a major contaminant of water resources. Escherichia coli (E. coli) is a commonly used indicator organism. It is well recognized that the fate of E. coli in surface water systems is governed by multiple physical, chemical, and biological factors. The aim of this work is to provide insight into the physical, chemical, and biological factors along with their interactions that are critical in the estimation of E. coli loads in surface streams. There are various models to predict E. coli loads in streams, but they tend to be system or site specific or overly complex without enhancing our understanding of these factors. Hence, based on available data, a Bayesian Neural Network (BNN) is presented for estimating E. coli loads based on physical, chemical, and biological factors in streams. The BNN has the dual advantage of overcoming the absence of quality data (with regards to consistency in data) and determination of mechanistic model parameters by employing a probabilistic framework. This study evaluates whether the BNN model can be an effective alternative tool to mechanistic models for E. coli loads estimation in streams. For this purpose, a comparison with a traditional model (LOADEST, USGS) is conducted. The models are compared for estimated E. coli loads based on available water quality data in Plum Creek, Texas. All the model efficiency measures suggest that overall E. coli loads estimations by the BNN model are better than the E. coli loads estimations by the LOADEST model on all the three occasions (three-fold cross validation). Thirteen factors were used for estimating E. coli loads with the exhaustive feature selection technique, which indicated that six of thirteen factors are important for estimating E. coli loads. Physical factors included temperature and dissolved oxygen; chemical factors include phosphate and ammonia; biological factors include suspended solids and chlorophyll. The results highlight that the LOADEST model estimates E. coli loads better in the smaller ranges, whereas the BNN model estimates E. coli loads better in the higher ranges. Hence, the BNN model can be used to design targeted monitoring programs and implement regulatory standards through TMDL programs. PMID:24511166

RETURN TO RUNNING FOLLOWING A KNEE DISARTICULATION AMPUTATION: A CASE REPORT

PubMed Central

Diebal-Lee, Angela R.; Kuenzi, Robert S.; Rábago, Christopher A.

2017-01-01

Background and Purpose The evolution of running-specific prostheses has empowered athletes with lower extremity amputations to run farther and faster than previously thought possible; but running with proper mechanics is still paramount to an injury-free, active lifestyle. The purpose of this case report was to describe the successful alteration of intact limb mechanics from a Rearfoot Striking (RFS) to a Non-Rearfoot Striking (NRFS) pattern in an individual with a knee disarticulation amputation, the associated reduction in Average Vertical Loading Rate (AVLR), and the improvement in functional performance following the intervention. Case description A 30 year-old male with a traumatic right knee disarticulation amputation reported complaints of residual limb pain with running distances greater than 5 km, limiting his ability to train toward his goal of participating in triathlons. Qualitative assessment of his running mechanics revealed a RFS pattern with his intact limb and a NRFS pattern with his prosthetic limb. A full body kinematic and kinetic running analysis using 3D motion capture and force plates was performed. The average intact limb loading rate was four-times greater (112 body weights/s) than in his prosthetic limb which predisposed him to possible injury. He underwent a three week running intervention with a certified running specialist to learn a NRFS pattern with his intact limb. Outcomes Immediately following the running intervention, he was able to run distances of over 10 km without pain. On a two-mile fitness test, he decreased his run time from 19:54 min to 15:14 min. Additionally, the intact limb loading rate was dramatically reduced to 27 body weights/s, nearly identical to the prosthetic limb (24 body weights/s). Discussion This case report outlines a detailed return to run program that targets proprioceptive and neuromuscular components, injury prevention, and specificity of training strategies. The outcomes of this case report are promising as they may spur additional research toward understanding how to eliminate potential injury risk factors associated with running after limb loss. Level of Evidence 4 PMID:28900572

Evaluation of effect of oil film of rotor bearing

NASA Astrophysics Data System (ADS)

Alekseeva, L. B.; Maksarov, V. V.

2018-03-01

The high-rpm rotors were subjected to the dynamic analysis. Oscillations of a rotor spinning in gapped bearings were considered. It was stated that the rotor necks motion pattern depends on a lot of factors: a ratio of static and dynamic loads on the bearing, radial clearance size, presence of oil film between a neck and a bearing, elastic and inertial properties of a mounting group. The most unfavourable mode where static and dynamic loads are equal was detected without taking into account the oil film impact. The impact of oil film on the bearing assembly dynamics is significant in high-rpm rotors. The presence of oil film can possibly cause rotor buckling failure and self-starting. Rotor motion stability in small was studied. Herewith, various schemes were considered. Expressions, determining the stability zones of a rigid rotor on the fixed support and the supports with elastic and inertial elements, were given.

Evolution of the soil cover of soccer fields

NASA Astrophysics Data System (ADS)

Belobrov, V. P.; Zamotaev, I. V.

2014-04-01

A soccer field can be considered a soil-like technogenic formation (STF). According to the theory of soil cover patterns, the artificially constructed (anthropogenic) soil cover of a soccer field is an analogue of a relatively homogeneous elementary soil area. However, the spatial homogeneity of the upper part (50-80 cm) of the STF of soccer fields is unstable and is subjected to gradual transformation under the impact of pedogenetic processes, agrotechnical loads, and mechanical loads during the games. This transformation is favored by the initial heterogeneity of the deep (buried) parts of the STF profile. The technogenic factors and elementary pedogenetic processes specify the dynamic functioning regime of the STF. In 50-75 years, the upper part of the STF is transformed into soil-like bodies with properties close to those in zonal soils. Certain micro- and nanopatterns of the soil cover are developed within the field creating its spatial heterogeneity.

River channel patterns: Braided, meandering, and straight

USGS Publications Warehouse

Leopold, Luna Bergere; Wolman, M. Gordon

1957-01-01

Channel pattern is used to describe the plan view of a reach of river as seen from an airplane, and includes meandering, braiding, or relatively straight channels.Natural channels characteristically exhibit alternating pools or deep reaches and riffles or shallow reaches, regardless of the type of pattern. The length of the pool or distance between riffles in a straight channel equals the straight line distance between successive points of inflection in the wave pattern of a meandering river of the same width. The points of inflection are also shallow points and correspond to riffles in the straight channel. This distance, which is half the wavelength of the meander, varies approximately as a linear function of channel width. In the data we analysed the meander wavelength, or twice the distance between successive riffles, is from 7 to 12 times the channel width. It is concluded that the mechanics which may lead to meandering operate in straight channels.River braiding is characterized by channel division around alluvial islands. The growth of an island begins as the deposition of a central bar which results from sorting and deposition of the coarser fractions of the load which locally cannot be transported. The bar grows downstream and in height by continued deposition on its surface, forcing the water into the flanking channels, which, to carry the flow, deepen and cut laterally into the original banks. Such deepening locally lowers the water surface and the central bar emerges as an island which becomes stabilized by vegetation. Braiding was observed in a small river in a laboratory. Measurements of the adjustments of velocity, depth, width, and slope associated with island development lead to the conclusion that braiding is one of the many patterns which can maintain quasi-equilibrium among discharge, load, and transporting ability. Braiding does not necessarily indicate an excess of total load.Channel cross section and pattern are ultimately controlled by the discharge and load provided by the drainage basin. It is important, therefore, to develop a picture of how the several variables involved in channel shape interact to result in observed channel characteristics. Such a rationale is summarized as follows:Channel width appears to be primarily a function of near-bankfull discharge, in conjunction with the inherent resistance of bed and bank to scour. Excessive width increases the shear on the bed at the expense of that on the bank and the reverse is true for very narrow widths. Because at high stages width adjustment can take place rapidly and with the evacuation or deposition of relatively small volumes of debris, achievement of a ,relatively stable width at high flow is a primary adjustment to which the further interadjustments between depth, velocity, slope, and roughness tend to accommodate.Channel roughness, to the extent that it is determined by particle size, is an independent factor related to the drainage basin rather than to the channel. Roughness in streams carrying fine material, however, is also a function of the dunes or other characteristics of bed configuration. Where roughness is independently determined as well as discharge and load, these studies indicate that a particular slope is associated with the roughness. At the width determined by the discharge, velocity and depth must be adjusted to satisfy quasi-equilibrium in accord with the particular slope. But if roughness also is variable, depending on the transitory configuration of the bed, then a number of combinations of velocity, depth, and slope will satisfy equilibrium.An increase in load at constant discharge, width, and caliber of load tends to be associated with an increasing slope if the roughness (dune or bed configuration) changes with the load. In the laboratory river an increase of load at constant discharge, width, and caliber resulted in progressive aggradation of long reaches of channel at constant slope.The adjustments of several variables tending toward the establishment of quasi-equilibrium in river channels lead to the different channel patterns observed in nature. For example, the data indicate that at a given discharge, meanders occur at smaller values of slope than do’ braids. Further, at the same slope braided channels are associated with higher bankfull discharges than are meanders. An additional example is provided by the division of discharge around islands in braided rivers which produces numerous small channels. The changes in slope, roughness, and channel shape which accompany this division are in accord with quasi-equilibrium adjustments observed in the comparison of large and small rivers.

GC-MS analyses and chemometric processing to discriminate the local and long-distance sources of PAHs associated to atmospheric PM2.5.

PubMed

Masiol, Mauro; Centanni, Elena; Squizzato, Stefania; Hofer, Angelika; Pecorari, Eliana; Rampazzo, Giancarlo; Pavoni, Bruno

2012-09-01

This study presents a procedure to differentiate the local and remote sources of particulate-bound polycyclic aromatic hydrocarbons (PAHs). Data were collected during an extended PM(2.5) sampling campaign (2009-2010) carried out for 1 year in Venice-Mestre, Italy, at three stations with different emissive scenarios: urban, industrial, and semirural background. Diagnostic ratios and factor analysis were initially applied to point out the most probable sources. In a second step, the areal distribution of the identified sources was studied by applying the discriminant analysis on factor scores. Third, samples collected in days with similar atmospheric circulation patterns were grouped using a cluster analysis on wind data. Local contributions to PM(2.5) and PAHs were then assessed by interpreting cluster results with chemical data. Results evidenced that significantly lower levels of PM(2.5) and PAHs were found when faster winds changed air masses, whereas in presence of scarce ventilation, locally emitted pollutants were trapped and concentrations increased. This way, an estimation of pollutant loads due to local sources can be derived from data collected in days with similar wind patterns. Long-range contributions were detected by a cluster analysis on the air mass back-trajectories. Results revealed that PM(2.5) concentrations were relatively high when air masses had passed over the Po Valley. However, external sources do not significantly contribute to the PAHs load. The proposed procedure can be applied to other environments with minor modifications, and the obtained information can be useful to design local and national air pollution control strategies.

Bifactor Structure for the Categorical Chinese Rosenberg Self-Esteem Scale.

PubMed

Xu, Menglin; Leung, Shing-On

2016-10-11

Recently, the bifactor model was suggested for the latent structure of the Rosenberg Self-Esteem Scale (RSES). The present paper investigates (i) the differences among bifactor, bifactor negative and other models; (ii) the effects of treating data as both categorical vs continuous; (iii) whether a problematic item in the Chinese RSES should be removed; and (iv) whether the final scoring would be affected. With a sample of 1.734 grade 4-6 school pupils in Hong Kong, we used BIC differences in addition to the usual model fit indices, and found that there was strong evidence for using the bifactor model (RMSEA = .052, 90% CI [.043, .062], CFI = .992, TLI = .984 for 9-item RSES categorical). Little difference is found between treating data as categorical or continuous for fit indices, but the factor loading patterns are better in categorical case. Keeping a problematic item has little effect on fit indices, but would lead to unexpected negative loading. The ranking of loadings within positive and negative items across different conditions are the same, which has important effects on scoring. Loadings in the method effects in the bifactor models are all positive (p < .001), which is different from previous research. All models show similar results on scoring, and support the usual simple sum score in most practice.

A Comparative Finite-Element Analysis of Bone Failure and Load Transfer of Osseointegrated Prostheses Fixations

PubMed Central

Tomaszewski, P. K.; Verdonschot, N.; Bulstra, S. K.

2010-01-01

An alternative solution to conventional stump–socket prosthetic limb attachment is offered by direct skeletal fixation. This study aimed to assess two percutaneous trans-femoral implants, the OPRA system (Integrum AB, Göteborg, Sweden), and the ISP Endo/Exo prosthesis (ESKA Implants AG, Lübeck, Germany) on bone failure and stem–bone interface mechanics both early post-operative (before bony ingrowth) and after full bone ingrowth. Moreover, mechanical consequences of implantation of those implants in terms of changed loading pattern within the bone and potential consequences on long-term bone remodeling were studied using finite-element models that represent the intact femur and implants fitted in amputated femora. Two experimentally measured loads from the normal walking cycle were applied. The analyses revealed that implantation of percutaneous prostheses had considerable effects on stress and strain energy density levels in bone. This was not only caused by the implant itself, but also by changed loading conditions in the amputated leg. The ISP design promoted slightly more physiological strain energy distribution (favoring long-term bone maintenance), but the OPRA design generated lower bone stresses (reducing bone fracture risk). The safety factor against mechanical failure of the two percutaneous designs was relatively low, which could be improved by design optimization of the implants. PMID:20309731

Electrophoretic deposition of dexamethasone-loaded gelatin nanospheres/chitosan coating and its dual function in anti-inflammation and osteogenesis.

PubMed

Qi, Hongfei; Chen, Qiang; Ren, Hailong; Wu, Xianglong; Liu, Xianhu; Lu, Tingli

2018-05-18

Surface modification of metallic implants with bioactive and biodegradable coatings could be a promising approach for bone regeneration. The objective of this study was to prepare chitosan/gelatin nanospheres (GNs) composite coating for the delivery of dexamethasone (DEX). GNs with narrow size distribution and negative surface charge were firstly prepared by a two-step desolvation method. Homogeneous and stable gelatin nanospheres/chitosan (GNs/CTS) composite coatings were formed by electrophoretic deposition (EPD). Drug loading, encapsulation efficiency and in vitro release of DEX were estimated using high performance liquid chromatography (HPLC). The anti-inflammatory effect of DEX-loaded coatings on macrophage RAW 264.7 cells was assessed by the secretion of tumour necrosis factor (TNF) and inducible nitric oxide synthase (iNOS). Osteogenic differentiation of MC3T3-E1 osteoblasts on DEX-loaded coatings was investigated by osteogenic gene expression and mineralization. The DEX in GNs/CTS composite coating showed a two-stage release pattern could not only suppress inflammation during the burst release period, but also promote osteogenic differentiation in the sustained release period. This study might offer a feasible method for modifying the surface of metallic implants in bone regeneration. Copyright © 2018 Elsevier B.V. All rights reserved.

Postcranial robusticity in Homo. III: Ontogeny.

PubMed

Ruff, C B; Walker, A; Trinkaus, E

1994-01-01

The influence of developmental factors on long-bone cross-sectional geometry and articular size in modern humans is investigated using two approaches: (1) an analysis of the effects of increased mechanical loading on long-bone structure when applied during different developmental periods, using data collected for a study of upper limb bone bilateral asymmetry in professional tennis players; and (2) an analysis of the relative timing of age changes in femoral dimensions among juveniles from the Pecos Pueblo Amerindian archaeological sample. Results of these analyses are used to interpret the femoral morphology of three pre-Recent Homo juveniles--the H. erectus KNM-WT 15000 and the archaic H. sapiens La Ferrassie 6 and Teshik-Tash 1--as well as observed differences in postcranial morphology between adult Recent and earlier Homo (Ruff et al., 1993). Our findings indicate the following: (1) There are age-related changes in long-bone diaphyseal envelope sensitivity to increased mechanical loading, with the periosteal envelope more responsive prior to mid-adolescence, and the endosteal envelope more responsive thereafter. The periosteal expansion and endosteal contraction of the diaphysis documented earlier for adult pre-Recent Homo relative to Recent humans (Ruff et al., 1993) is thus consistent with a developmental response to increased mechanical loading applied throughout life. The relatively large medullary cavity in the 11-12-year-old KNM-WT 15000 femur is also consistent with this model. However, the two archaic H. sapiens juveniles show relatively small medullary cavities, possibly indicating a modified developmental pattern in this group. (2) Articulations follow a growth pattern similar to that of long-bone length (and stature), while cross-sectional diaphyseal dimensions (cortical area, second moments of area) show a contrasting growth pattern, with slower initial growth from childhood through mid-adolescence, followed by a "catch-up" period that continues through early adulthood. This latter pattern is more similar to the growth curve for body weight, and may in fact partially reflect adaptation of the diaphysis to increased weight bearing. Because of these different growth patterns, articulations appear relatively large, and diaphyseal breadths relatively small during late childhood to mid-adolescence (i.e., about 9-13 years), when compared to adults from the same population. KNM-WT 15000 shows this same proportional difference from adult early Homo specimens, which is therefore interpreted as simply a developmental consequence of his age at death.(ABSTRACT TRUNCATED AT 400 WORDS)

The two-factor model of psychopathic personality: evidence from the psychopathic personality inventory.

PubMed

Marcus, David K; Fulton, Jessica J; Edens, John F

2013-01-01

Psychopathy or psychopathic personality disorder represents a constellation of traits characterized by superficial charm, egocentricity, irresponsibility, fearlessness, persistent violation of social norms, and a lack of empathy, guilt, and remorse. Factor analyses of the Psychopathic Personality Inventory (PPI)typically yield two factors: Fearless Dominance (FD) and Self-Centered Impulsivity (SCI). Additionally, the Coldheartedness (CH) subscale typically does not load on either factor. The current paper includes a meta-analysis of studies that have examined theoretically important correlates of the two PPI factors and CH. Results suggest that (a) FD and SCI are orthogonal or weakly correlated, (b) each factor predicts distinct (and sometimes opposite) correlates, and (c) the FD factor is not highly correlated with most other measures of psychopathy. This pattern of results raises important questions about the relation between FD and SCI and the role of FD in conceptualizations of psychopathy. Our findings also indicate the need for future studies using the two-factor model of the PPI to conduct moderational analyses to examine potential interactions between FD and SCI in the prediction of important criterion measures.

Calibration of the live load factor in LRFD design guidelines.

DOT National Transportation Integrated Search

2010-09-01

The Load and Resistant Factor Design (LRFD) approach is based on the concept of structural reliability. The approach is : more rational than the former design approaches such as Load Factor Design or Allowable Stress Design. The LRFD : Specification ...

Calibration of the live load factor in LRFD design guidelines : [revised].

DOT National Transportation Integrated Search

2011-07-01

The Load and Resistant Factor Design (LRFD) approach is based on the concept of structural reliability. The approach is : more rational than the former design approaches such as Load Factor Design or Allowable Stress Design. The LRFD : Specification ...

CFTR expression and organ damage in cystic fibrosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tizzano, E.; Chitayat, D.; Buchwald, M.

1994-09-01

To assist our understanding of the origin of organ damage caused by cystic fibrosis (CF) disease, we have analyzed the pattern of expression of the CF gene (CFTR). mRNA in situ hybridization analysis was carried out in human fetal, newborn, infant and adult tissues and the abundance of the mRNA was correlated with the known pathology at the various stages of human development. Analysis of the pattern of expression indicates a constitutive level of mRNA in gastrointestinal tissues starting during early development and maintained throughout life. Prenatal respiratory tissues show qualitative and quantitative major differences in comparison to postnatal lungmore » samples. Male reproductive tissues show high levels of expression in the head of the epididymis compared with the rest of the male ducts. Female reproductive tissues show a variable pattern of expression at different stages during fetal development and during puberty probably due to changes in hormonal levels. Gastrointestinal and male reproductive tissues have a consistent pathology at birth, whereas no lung abnormalities have been described in newborns affected by CF. Our results show that there is no exact correlations between organ damage present at birth and the degree of CFTR expression. To explain these observations, we hypothesize that the pathogenesis of organ damage in CF depend on at least three factors: the rate of CFTR-mediated fluid secretion, differences in genotype and environmental factors, such as the amount of macromolecules in the lumen of the ducts. This last element predicts that damage will occur in tissues with high protein loads and low flow rates (e.g. pancreas, epididymis), where the absence of CFTR function leads to obstruction and pathology. Organs that express CFTR but with no significant damage (e.g. prenatal lung, female reproductive tissues), will have a low protein load and a high flow rates.« less

Contrasting visual working memory for verbal and non-verbal material with multivariate analysis of fMRI

PubMed Central

Habeck, Christian; Rakitin, Brian; Steffener, Jason; Stern, Yaakov

2012-01-01

We performed a delayed-item-recognition task to investigate the neural substrates of non-verbal visual working memory with event-related fMRI (‘Shape task’). 25 young subjects (mean age: 24.0 years; STD=3.8 years) were instructed to study a list of either 1,2 or 3 unnamable nonsense line drawings for 3 seconds (‘stimulus phase’ or STIM). Subsequently, the screen went blank for 7 seconds (‘retention phase’ or RET), and then displayed a probe stimulus for 3 seconds in which subject indicated with a differential button press whether the probe was contained in the studied shape-array or not (‘probe phase’ or PROBE). Ordinal Trend Canonical Variates Analysis (Habeck et al., 2005a) was performed to identify spatial covariance patterns that showed a monotonic increase in expression with memory load during all task phases. Reliable load-related patterns were identified in the stimulus and retention phase (p<0.01), while no significant pattern could be discerned during the probe phase. Spatial covariance patterns that were obtained from an earlier version of this task (Habeck et al., 2005b) using 1, 3, or 6 letters (‘Letter task’) were also prospectively applied to their corresponding task phases in the current non-verbal task version. Interestingly, subject expression of covariance patterns from both verbal and non-verbal retention phases correlated positively in the non-verbal task for all memory loads (p<0.0001). Both patterns also involved similar frontoparietal brain regions that were increasing in activity with memory load, and mediofrontal and temporal regions that were decreasing. Mean subject expression of both patterns across memory load during retention also correlated positively with recognition accuracy (dL) in the Shape task (p<0.005). These findings point to similarities in the neural substrates of verbal and non-verbal rehearsal processes. Encoding processes, on the other hand, are critically dependent on the to-be-remembered material, and seem to necessitate material-specific neural substrates. PMID:22652306

Radiation pattern of a borehole radar antenna

USGS Publications Warehouse

Ellefsen, K.J.; Wright, D.L.

2002-01-01

To understand better how a borehole antenna radiates radar waves into a formation, this phenomenon is simulated numerically using the finite-difference, time-domain method. The simulations are of two different antenna models that include features like a driving point fed by a coaxial cable, resistive loading of the antenna, and a water-filled borehole. For each model, traces are calculated in the far-field region, and then, from these traces, radiation patterns are calculated. The radiation patterns show that the amplitude of the radar wave is strongly affected by its frequency, its propagation direction, and the resistive loading of the antenna.

Associations of dietary patterns with bone mass, muscle strength and balance in a cohort of Australian middle-aged women.

PubMed

Wu, Feitong; Wills, Karen; Laslett, Laura L; Oldenburg, Brian; Jones, Graeme; Winzenberg, Tania

2017-10-01

Influences of dietary patterns on musculoskeletal health are poorly understood in middle-aged women. This cross-sectional analysis from a cohort of 347 women (aged 36-57 years) aimed to examine associations between dietary patterns and musculoskeletal health outcomes in middle-aged women. Diet was measured by the Cancer Council of Victoria FFQ. Total body bone mineral content (TB BMC), femoral neck and lumbar spine bone density (dual-energy X-ray absorptiometry), lower limbs muscle strength (LMS) and balance tests (timed up and go test, step test, functional reach test (FRT) and lateral reach test) were also measured. Exploratory factor analysis was used to identify dietary patterns and scores for each pattern generated using factor loadings with absolute values ≥0·20. Associations between food pattern scores and musculoskeletal outcomes were assessed using multivariable linear regression. Three dietary patterns were identified: 'Healthy' (high consumption of a plant-based diet - vegetables, legumes, fruit, tomatoes, nuts, snacks, garlic, whole grains and low intake of high-fat dairy products), 'high protein, high fat' (red meats, poultry, processed meats, potatoes, cruciferous and dark-yellow vegetables, fish, chips, spirits and high-fat dairy products) and 'Processed foods' (high intakes of meat pies, hamburgers, beer, sweets, fruit juice, processed meats, snacks, spirits, pizza and low intake of cruciferous vegetables). After adjustment for confounders, Healthy pattern was positively associated with LMS, whereas Processed foods pattern was inversely associated with TB BMC and FRT. The associations were not significant after accounting for multiple comparisons. There were no associations with any other outcomes. These results suggest that maintaining a healthy diet could contribute to bone acquisition, muscle strength and balance in adult life. However, while they provide some support for further investigating dietary strategies for prevention of age-related loss of muscle and deterioration in balance, the exploratory nature of the analyses means that confirmation in longitudinal studies and/or trials with pre-specified hypotheses is needed.

Influence of Training Load and Altitude on HRV Fatigue Patterns in Elite Nordic Skiers.

PubMed

Schmitt, Laurent; Regnard, Jacques; Coulmy, Nicolas; Millet, Gregoire P

2018-06-14

We aimed to analyse the relationship between training load/intensity and different heart rate variability (HRV) fatigue patterns in 57 elite Nordic-skiers. 1063 HRV tests were performed during 5 years. R-R intervals were recorded in resting supine (SU) and standing (ST) positions. Heart rate, low (LF), high (HF) frequency powers of HRV were determined. Training volume, training load (TL, a.u.) according to ventilatory threshold 1 (VT1) and VT2 were measured in zones I≤VT1; VT1VT2, IV for strength. TL was performed at 81.6±3.5% in zone I, 0.9±0.9% in zone II, 5.0±3.6% in zone III, 11.6±6.3% in zone IV. 172 HRV tests matched a fatigue state and four HRV fatigue patterns (F) were statistically characterized as F(HF-LF-)SU_ST for 121 tests, F(LF+SULF-ST) for 18 tests, F(HF-SUHF+ST) for 26 tests and F(HF+SU) for 7 tests. The occurrence of fatigue states increased substantially with the part of altitude training time (r2=0.52, p<0.001). This study evidenced that there is no causal relationship between training load/intensity and HRV fatigue patterns. Four fatigue-shifted HRV patterns were sorted. Altitude training periods appeared critical as they are likely to increase the overreaching risks. © Georg Thieme Verlag KG Stuttgart · New York.

Trunk coordination in healthy and chronic nonspecific low back pain subjects during repetitive flexion-extension tasks: Effects of movement asymmetry, velocity and load.

PubMed

Mokhtarinia, Hamid Reza; Sanjari, Mohammad Ali; Chehrehrazi, Mahshid; Kahrizi, Sedigheh; Parnianpour, Mohamad

2016-02-01

Multiple joint interactions are critical to produce stable coordinated movements and can be influenced by low back pain and task conditions. Inter-segmental coordination pattern and variability were assessed in subjects with and without chronic nonspecific low back pain (CNSLBP). Kinematic data were collected from 22 CNSLBP and 22 healthy volunteers during repeated trunk flexion-extension in various conditions of symmetry, velocity, and loading; each at two levels. Sagittal plane angular data were time normalized and used to calculate continuous relative phase for each data point. Mean absolute relative phase (MARP) and deviation phase (DP) were derived to quantify lumbar-pelvis and pelvis-thigh coordination patterns and variability. Statistical analysis revealed more in-phase coordination pattern in CNSLBP (p=0.005). There was less adaptation in the DP for the CNSLBP group, as shown by interactions of Group by Load (p=.008) and Group by Symmetry by Velocity (p=.03) for the DP of pelvis-thigh and lumbar-pelvis couplings, respectively. Asymmetric (p<0.001) and loaded (p=0.04) conditions caused less in-phase coordination. Coordination variability was higher during asymmetric and low velocity conditions (p<0.001). In conclusion, coordination pattern and variability could be influenced by trunk flexion-extension conditions. CNSLBP subjects demonstrated less adaptability of movement pattern to the demands of the flexion-extension task. Copyright © 2015 Elsevier B.V. All rights reserved.

Research notes : customized live-load factors for bridge load rating.

DOT National Transportation Integrated Search

2007-03-01

The state-of-the-art approach to load rating bridges is the Load and Resistance Factor Rating (LRFR) method, supported by the Federal Highway Administration and the American Association of State Highway and Transportation Officials. This approach ens...

Development of the Rules Governing the Strength of Airplanes. Part I : German Loading Conditions up to 1926

NASA Technical Reports Server (NTRS)

Kussner, H G; Thalau, Karl

1933-01-01

Load factors and loading conditions are presented for German aircraft. Loading conditions under various stress factors are presented along with a breakdown of individual aircraft components such as landing gear, wings, etc.

PIV measurements in a compact return diffuser under multi-conditions

NASA Astrophysics Data System (ADS)

Zhou, L.; Lu, W. G.; Shi, W. D.

2013-12-01

Due to the complex three-dimensional geometries of impellers and diffusers, their design is a delicate and difficult task. Slight change could lead to significant changes in hydraulic performance and internal flow structure. Conversely, the grasp of the pump's internal flow pattern could benefit from pump design improvement. The internal flow fields in a compact return diffuser have been investigated experimentally under multi-conditions. A special Particle Image Velocimetry (PIV) test rig is designed, and the two-dimensional PIV measurements are successfully conducted in the diffuser mid-plane to capture the complex flow patterns. The analysis of the obtained results has been focused on the flow structure in diffuser, especially under part-load conditions. The vortex and recirculation flow patterns in diffuser are captured and analysed accordingly. Strong flow separation and back flow appeared at the part-load flow rates. Under the design and over-load conditions, the flow fields in diffuser are uniform, and the flow separation and back flow appear at the part-load flow rates, strong back flow is captured at one diffuser passage under 0.2Qdes.

Computation of spanwise distribution of circulation and lift coefficient for flapped wings of arbitrary planform

NASA Technical Reports Server (NTRS)

Razak, K.

1980-01-01

The question of the effect of distribution and magnitude of spanwise circulation and shed vorticity from an airplane wing on the distribution pattern of agricultural products distributed from an airplane was studied. The first step in an analysis of this question is the determination of the actual distribution of lift along an airplane wing, from which the pattern of shed vorticity can be determined. A procedure is developed to calculate the span loading for flapped and unflapped wings of arbitrary aspect ratio and taper ratio. The procedure was programmed on a small programmable calculator, the Hewlett Packard HP-97, and also was programmed in BASIC language. They could be used to explore the variations in span loading that can be secured by variable flap deflections or the effect of flying at varying air speeds at different airplane gross weights. Either an absolute evaluation of span loading can be secured or comparative span loading can be evaluated to determine their effect on swath width and swath distribution pattern. The programs are intended to assist the user in evaluating the effect of a given spanload distribution.

Genotype patterns at PICALM, CR1, BIN1, CLU, and APOE genes are associated with episodic memory

PubMed Central

Barral, S.; Bird, T.; Goate, A.; Farlow, M.R.; Diaz-Arrastia, R.; Bennett, D.A.; Graff-Radford, N.; Boeve, B.F.; Sweet, R.A.; Stern, Y.; Wilson, R.S.; Foroud, T.; Ott, J.; Green, Robert; Kowall, Neil; Farrer, Lindsay; Williamson, Jennifer; Santana, Vincent; Schmechel, Donald; Gaskel, Peter; Ghetti, Bernardino; Farlow, Martin R.; Faber, Kelley; Prentice, Heather; Horner, Kelly; Growdon, John H.; Blacker, Deborah; Tanzi, Rudolph E.; Hyman, Bradley T.; Boeve, Bradley; Kuntz, Karen; Norgaard, Lindsay; Larson, Nathan; Kistler, Dana; Parfitt, Francine; Haddow, Jenny; Silverman, Jeremy; Beeri, Michal Schnaider; Sano, Mary; Wang, Joy; Lally, Rachel; Johnson, Nancy; Mesulam, Marcel; Weintraub, Sandra; Bigio, Eileen; Kaye, Jeffery; Kramer, Patricia; Payne-Murphy, Jessica; Bennett, David; Jacobs, Holli; Chang, Jeen-Soo; Arends, Danielle; Harrell, Lindy; Bartzokis, George; Cummings, Jeffery; Lu, Po H.; Toland, Usha; Smith, Charles; Brickhouse, Alise; Trojanowski, John; Van Deerlin, Vivianna; McCarty Wood, Elisabeth; DeKosky, Steven; Sweet, Robert; Weamer, Elise; Chui, Helena; Varpetian, Arousiak; Diaz-Arrastia, Ramon; Rosenberg, Roger; Davis, Barbara; Bird, Thomas; Schellenberg, Gerard D.; Raskind, Murray; Rumbaugh, Malia; Nickel, Kate; Goate, Alison; Morris, John; Norton, Joanne; Levitch, Denise; Grant, Betsy; Coats, Mary; Levey, Allen; Rosen, Ami; Anosike, Ezinna

2012-01-01

Objective: Several genome-wide association studies (GWAS) have associated variants in late-onset Alzheimer disease (LOAD) susceptibility genes; however, these single nucleotide polymorphisms (SNPs) have very modest effects, suggesting that single SNP approaches may be inadequate to identify genetic risks. An alternative approach is the use of multilocus genotype patterns (MLGPs) that combine SNPs at different susceptibility genes. Methods: Using data from 1,365 subjects in the National Institute on Aging Late-Onset Alzheimer's Disease Family Study, we conducted a family-based association study in which we tabulated MLGPs for SNPs at CR1, BIN1, CLU, PICALM, and APOE. We used generalized estimating equations to model episodic memory as the dependent endophenotype of LOAD and the MLGPs as predictors while adjusting for sex, age, and education. Results: Several genotype patterns influenced episodic memory performance. A pattern that included PICALM and CLU was the strongest genotypic profile for lower memory performance (β = −0.32, SE = 0.19, p = 0.021). The effect was stronger after addition of APOE (p = 0.016). Two additional patterns involving PICALM, CR1, and APOE and another pattern involving PICALM, BIN1, and APOE were also associated with significantly poorer memory performance (β = −0.44, SE = 0.09, p = 0.009 and β = −0.29, SE = 0.07, p = 0.012) even after exclusion of patients with LOAD. We also identified genotype pattern involving variants in PICALM, CLU, and APOE as a predictor of better memory performance (β = 0.26, SE = 0.10, p = 0.010). Conclusions: MLGPs provide an alternative analytical approach to predict an individual's genetic risk for episodic memory performance, a surrogate indicator of LOAD. Identifying genotypic patterns contributing to the decline of an individual's cognitive performance may be a critical step along the road to preclinical detection of Alzheimer disease. PMID:22539578

Population-based learning of load balancing policies for a distributed computer system

NASA Technical Reports Server (NTRS)

Mehra, Pankaj; Wah, Benjamin W.

1993-01-01

Effective load-balancing policies use dynamic resource information to schedule tasks in a distributed computer system. We present a novel method for automatically learning such policies. At each site in our system, we use a comparator neural network to predict the relative speedup of an incoming task using only the resource-utilization patterns obtained prior to the task's arrival. Outputs of these comparator networks are broadcast periodically over the distributed system, and the resource schedulers at each site use these values to determine the best site for executing an incoming task. The delays incurred in propagating workload information and tasks from one site to another, as well as the dynamic and unpredictable nature of workloads in multiprogrammed multiprocessors, may cause the workload pattern at the time of execution to differ from patterns prevailing at the times of load-index computation and decision making. Our load-balancing policy accommodates this uncertainty by using certain tunable parameters. We present a population-based machine-learning algorithm that adjusts these parameters in order to achieve high average speedups with respect to local execution. Our results show that our load-balancing policy, when combined with the comparator neural network for workload characterization, is effective in exploiting idle resources in a distributed computer system.

Limiter Observations during W7-X First Plasmas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wurden, Glen Anthony; Biedermann, C.; Effenberg, F.

During the first operational phase (referred to as OP1.1) of the new Wendelstein 7-X (W7-X) stellarator, five poloidal graphite limiters were mounted on the inboard side of the vacuum vessel, one in each of the five toroidal modules which form the W7-X vacuum vessel. Each limiter consisted of nine specially shaped graphite tiles, designed to conform to the last closed field line geometry in the bean-shaped section of the standard OP1.1 magnetic field configuration (Sunn Pedersen et al 2015 Nucl. Fusion 55 126001). Here, we observed the limiters with multiple infrared and visible camera systems, as well as filtered photomultipliers.more » Power loads are calculated from infrared (IR) temperature measurements using THEODOR, and heating patterns (dual stripes) compare well with field line mapping and EMC3-EIRENE predictions. While the poloidal symmetry of the heat loads was excellent, the toroidal heating pattern showed up to a factor of 2× variation, with peak heat loads on Limiter 1. The total power intercepted by the limiters was up to ~60% of the input ECRH heating power. Calorimetry using bulk tile heating (measured via post-shot IR thermography) on Limiter 3 showed a difference between short high power discharges, and longer lower power ones, with regards to the fraction of energy deposited on the limiters. Finally, fast heating transients, with frequency >1 kHz were detected, and their visibility was enhanced by the presence of surface coatings which developed on the limiters by the end of the campaign.« less

Functional and morphological correlates of mandibular symphyseal form in a living human sample.

PubMed

Holton, Nathan E; Franciscus, Robert G; Ravosa, Matthew J; Southard, Thomas E

2014-03-01

Variation in recent human mandibular form is often thought to reflect differences in masticatory behavior associated with variation in food preparation and subsistence strategies. Nevertheless, while mandibular variation in some human comparisons appear to reflect differences in functional loading, other comparisons indicate that this relationship is not universal. This suggests that morphological variation in the mandible is influenced by other factors that may obscure the effects of loading on mandibular form. It is likely that highly strained mandibular regions, including the corpus, are influenced by well-established patterns of lower facial skeletal integration. As such, it is unclear to what degree mandibular form reflects localized stresses incurred during mastication vs. a larger set of correlated features that may influence bone distribution patterns. In this study, we examine the relationship between mandibular symphyseal bone distribution (i.e., second moments of area, cortical bone area) and masticatory force production (i.e., in vivo maximal bite force magnitude and estimated symphyseal bending forces) along with lower facial shape variation in a sample of n = 20 living human male subjects. Our results indicate that while some aspects of symphyseal form (e.g., wishboning resistance) are significantly correlated with estimates of symphyseal bending force magnitude, others (i.e., vertical bending resistance) are more closely tied to variation in lower facial shape. This suggests that while the symphysis reflects variation in some variables related to functional loading, the complex and multifactorial influences on symphyseal form underscores the importance of exercising caution when inferring function from the mandible especially in narrow taxonomic comparisons. Copyright © 2013 Wiley Periodicals, Inc.

Limiter Observations during W7-X First Plasmas

DOE PAGES

Wurden, Glen Anthony; Biedermann, C.; Effenberg, F.; ...

2017-04-03

During the first operational phase (referred to as OP1.1) of the new Wendelstein 7-X (W7-X) stellarator, five poloidal graphite limiters were mounted on the inboard side of the vacuum vessel, one in each of the five toroidal modules which form the W7-X vacuum vessel. Each limiter consisted of nine specially shaped graphite tiles, designed to conform to the last closed field line geometry in the bean-shaped section of the standard OP1.1 magnetic field configuration (Sunn Pedersen et al 2015 Nucl. Fusion 55 126001). Here, we observed the limiters with multiple infrared and visible camera systems, as well as filtered photomultipliers.more » Power loads are calculated from infrared (IR) temperature measurements using THEODOR, and heating patterns (dual stripes) compare well with field line mapping and EMC3-EIRENE predictions. While the poloidal symmetry of the heat loads was excellent, the toroidal heating pattern showed up to a factor of 2× variation, with peak heat loads on Limiter 1. The total power intercepted by the limiters was up to ~60% of the input ECRH heating power. Calorimetry using bulk tile heating (measured via post-shot IR thermography) on Limiter 3 showed a difference between short high power discharges, and longer lower power ones, with regards to the fraction of energy deposited on the limiters. Finally, fast heating transients, with frequency >1 kHz were detected, and their visibility was enhanced by the presence of surface coatings which developed on the limiters by the end of the campaign.« less

Weigh-in-motion (WIM) data for site-specific LRFR bridge load rating.

DOT National Transportation Integrated Search

2011-08-12

The live load factors in the Load and Resistant Factor Rating (LRFR) Manual are based on load data from Ontario : thought to be representative of traffic volumes nationwide. However, in accordance with the methodology for : developing site-specific l...

Pattern generating and reflex-like processes controlling aiming movements in the presence of inertia, damping and gravity. A theoretical note.

PubMed

Kalveram, K T

1991-01-01

A model is proposed, in which goal-directed movements of the forearm are controlled by a central pattern generator (CPG) initiated for exactly one period, and by reflex-analogous processes. Movement width is proportional to the amplitude factor of the CPG's output, and to the square of the CPG's period length. The period duration can be freely selected, thus enabling the CPG to accommodate its time scale to the period of others CPG's. Parameters which influence movement accuracy can be adjusted by means of closed control loop, which are discrete with respect to time: The time unit corresponds to the period of the CPG. For instance, momentum adjustment balances the CPG in such a manner that the velocity of the arm becomes zero on termination of the period, while gain adjustment serves to attain a correct movement length in the presence of an inertial load. Friction, stiffness and gravitational force are neutralized by additional reflex-type processes, interpretable as positive feedback loops with adjustable gain factors, using position and velocity signals.

Unnecessary antiretroviral treatment switches and accumulation of HIV resistance mutations; two arguments for viral load monitoring in Africa.

PubMed

Sigaloff, Kim C E; Hamers, Raph L; Wallis, Carole L; Kityo, Cissy; Siwale, Margaret; Ive, Prudence; Botes, Mariette E; Mandaliya, Kishor; Wellington, Maureen; Osibogun, Akin; Stevens, Wendy S; van Vugt, Michèle; de Wit, Tobias F Rinke

2011-09-01

This study aimed to investigate the consequences of using clinicoimmunological criteria to detect antiretroviral treatment (ART) failure and guide regimen switches in HIV-infected adults in sub-Saharan Africa. Frequencies of unnecessary switches, patterns of HIV drug resistance, and risk factors for the accumulation of nucleoside reverse transcriptase inhibitor (NRTI)-associated mutations were evaluated. Cross-sectional analysis of adults switching ART regimens at 13 clinical sites in 6 African countries was performed. Two types of failure identification were compared: diagnosis of clinicoimmunological failure without viral load testing (CIF only) or CIF with local targeted viral load testing (targeted VL). After study enrollment, reference HIV RNA and genotype were determined retrospectively. Logistic regression assessed factors associated with multiple thymidine analogue mutations (TAMs) and NRTI cross-resistance (≥2 TAMs or Q151M or K65R/K70E). Of 250 patients with CIF switching to second-line ART, targeted VL was performed in 186. Unnecessary switch at reference HIV RNA <1000 copies per milliliter occurred in 46.9% of CIF only patients versus 12.4% of patients with targeted VL (P < 0.001). NRTI cross-resistance was observed in 48.0% of 183 specimens available for genotypic analysis, comprising ≥2 TAMs (37.7%), K65R (7.1%), K70E (3.3%), or Q151M (3.3%). The presence of NRTI cross-resistance was associated with the duration of ART exposure and zidovudine use. Clinicoimmunological monitoring without viral load testing resulted in frequent unnecessary regimen switches. Prolonged treatment failure was indicated by extensive NRTI cross-resistance. Access to virological monitoring should be expanded to prevent inappropriate switches, enable early failure detection and preserve second-line treatment options in Africa.

3D-printed dimethyloxallyl glycine delivery scaffolds to improve angiogenesis and osteogenesis.

PubMed

Min, Zhu; Shichang, Zhao; Chen, Xin; Yufang, Zhu; Changqing, Zhang

2015-08-01

Angiogenesis-osteogenesis coupling processes are vital in bone tissue engineering. Normal biomaterials implanted in bone defects have issues in the sufficient formation of blood vessels, especially in the central part. Single delivery of vascular endothelial growth factors (VEGF) to foci in previous studies did not show satisfactory results due to low loading doses, a short protein half-life and low efficiency. Development of a hypoxia-mimicking microenvironment for cells by local prolyl-4-hydroxylase inhibitor release, which can stabilize hypoxia-inducible factor 1α (HIF-1α) expression, is an alternative method. The aim of this study was to design a dimethyloxallyl glycine (DMOG) delivering scaffold composed of mesoporous bioactive glasses and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) polymers (MPHS scaffolds), so as to investigate whether the sustained release of DMOG promotes local angiogenesis and bone healing. The morphology and microstructure of composite scaffolds were characterized. The DMOG release patterns from scaffolds loaded with different DMOG dosages were evaluated, and the effects of DMOG delivery on human bone marrow stromal cell (hBMSC) adhesion, viability, proliferation, osteogenic differentiation and angiogenic-relative gene expressions with scaffolds were also investigated. In vivo studies were carried out to observe vascular formations and new bone ingrowth with DMOG-loaded scaffolds. The results showed that DMOG could be released in a sustained manner over 4 weeks from MPHS scaffolds and obviously enhance the angiogenesis and osteogenesis in the defects. Microfil perfusion showed a significantly increased formation of vessels in the defects with DMOG delivery. Furthermore, micro-CT imaging and fluorescence labeling indicated larger areas of bone formation for DMOG-loaded scaffolds. It is concluded that MPHS-DMOG scaffolds are promising for enhancing bone healing of osseous defects.

Tuberculous meningitis is associated with higher cerebrospinal HIV-1 viral loads compared to other HIV-1-associated meningitides.

PubMed

Seipone, Ikanyeng D; Singh, Ravesh; Patel, Vinod B; Singh, Avashna; Gordon, Michelle L; Muema, Daniel M; Dheda, Keertan; Ndung'u, Thumbi

2018-01-01

To gain a better understanding of the immunopathogenesis of tuberculous meningitis (TBM) and identify potential diagnostic biomarkers that may discriminate TBM from other HIV-1-associated meningitides, we assessed HIV-1 viral load levels, drug resistance patterns in antiretroviral therapy (ART)-experienced patients with persistent viremia and soluble immunological analytes in peripheral blood and cerebrospinal fluid (CSF) of HIV-1 infected patients with TBM versus other meningitides. One hundred and three matched blood and CSF samples collected from HIV-1 infected patients with TBM or other meningitides presenting at a hospital in Durban, South Africa, from January 2009 to December 2011 were studied. HIV-1 RNA and 28 soluble immunological potential biomarkers were quantified in blood plasma and CSF. Viremic samples were assessed for HIV-1 drug resistance mutations. There were 16 TBM, 46 probable TBM, 35 non-TBM patients, and six unclassifiable patients. TBM and non-TBM patients did not differ in median plasma viral load but TBM patients had significantly higher median CSF viral load than non-TBM participants (p = 0.0005). No major drug resistance mutations were detected in viremic samples. Interleukin (IL)-1β, IL-17, platelet derived growth factor (PDGF)-BB, granulocyte colony stimulating factor (G-CSF) and cathelicidin were significantly elevated in the CNS of TBM participants compared to other patients although these associations were lost after correction for false discovery. Our data suggest that TB co-infection of the CNS is associated with enhanced localized HIV-1 viral replication but none of the evaluated soluble immunological potential biomarkers could reliably distinguish TBM from other HIV-associated meningitides.

Tuberculous meningitis is associated with higher cerebrospinal HIV-1 viral loads compared to other HIV-1-associated meningitides

PubMed Central

Seipone, Ikanyeng D.; Singh, Ravesh; Patel, Vinod B.; Singh, Avashna; Gordon, Michelle L.; Muema, Daniel M.; Dheda, Keertan

2018-01-01

To gain a better understanding of the immunopathogenesis of tuberculous meningitis (TBM) and identify potential diagnostic biomarkers that may discriminate TBM from other HIV-1-associated meningitides, we assessed HIV-1 viral load levels, drug resistance patterns in antiretroviral therapy (ART)-experienced patients with persistent viremia and soluble immunological analytes in peripheral blood and cerebrospinal fluid (CSF) of HIV-1 infected patients with TBM versus other meningitides. One hundred and three matched blood and CSF samples collected from HIV-1 infected patients with TBM or other meningitides presenting at a hospital in Durban, South Africa, from January 2009 to December 2011 were studied. HIV-1 RNA and 28 soluble immunological potential biomarkers were quantified in blood plasma and CSF. Viremic samples were assessed for HIV-1 drug resistance mutations. There were 16 TBM, 46 probable TBM, 35 non-TBM patients, and six unclassifiable patients. TBM and non-TBM patients did not differ in median plasma viral load but TBM patients had significantly higher median CSF viral load than non-TBM participants (p = 0.0005). No major drug resistance mutations were detected in viremic samples. Interleukin (IL)-1β, IL-17, platelet derived growth factor (PDGF)-BB, granulocyte colony stimulating factor (G-CSF) and cathelicidin were significantly elevated in the CNS of TBM participants compared to other patients although these associations were lost after correction for false discovery. Our data suggest that TB co-infection of the CNS is associated with enhanced localized HIV-1 viral replication but none of the evaluated soluble immunological potential biomarkers could reliably distinguish TBM from other HIV-associated meningitides. PMID:29394269

Body mass index affects knee joint mechanics during gait differently with and without moderate knee osteoarthritis.

PubMed

Harding, Graeme T; Hubley-Kozey, Cheryl L; Dunbar, Michael J; Stanish, William D; Astephen Wilson, Janie L

2012-11-01

Obesity is a highly cited risk factor for knee osteoarthritis (OA), but its role in knee OA pathogenesis and progression is not as clear. Excess weight may contribute to an increased mechanical burden and altered dynamic movement and loading patterns at the knee. The objective of this study was to examine the interacting role of moderate knee OA disease presence and obesity on knee joint mechanics during gait. Gait analysis was performed on 104 asymptomatic and 140 individuals with moderate knee OA. Each subject group was divided into three body mass categories based on body mass index (BMI): healthy weight (BMI<25), overweight (25≤BMI≤30), and obese (BMI>30). Three-dimensional knee joint angles and net external knee joint moments were calculated and waveform principal component analysis (PCA) was applied to extract major patterns of variability from each. PC scores for major patterns were compared between groups using a two-factor ANOVA. Significant BMI main effects were found in the pattern of the knee adduction moment, the knee flexion moment, and the knee rotation moment during gait. Two interaction effects between moderate OA disease presence and BMI were also found that described different changes in the knee flexion moment and the knee flexion angle with increased BMI with and without knee OA. Our results suggest that increased BMI is associated with different changes in biomechanical patterns of the knee joint during gait depending on the presence of moderate knee OA. Copyright © 2012 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Nanometal Skin of Plasmonic Heterostructures for Highly Efficient Near-Field Scattering Probes

NASA Astrophysics Data System (ADS)

Zito, Gianluigi; Rusciano, Giulia; Vecchione, Antonio; Pesce, Giuseppe; di Girolamo, Rocco; Malafronte, Anna; Sasso, Antonio

2016-08-01

In this work, atomic force microscopy probes are functionalized by virtue of self-assembling monolayers of block copolymer (BCP) micelles loaded either with clusters of silver nanoparticles or bimetallic heterostructures consisting of mixed species of silver and gold nanoparticles. The resulting self-organized patterns allow coating the tips with a sort of nanometal skin made of geometrically confined nanoislands. This approach favors the reproducible engineering and tuning of the plasmonic properties of the resulting structured tip by varying the nanometal loading of the micelles. The newly conceived tips are applied for experiments of tip-enhanced Raman scattering (TERS) spectroscopy and scattering-type scanning near-field optical microscopy (s-SNOM). TERS and s-SNOM probe characterizations on several standard Raman analytes and patterned nanostructures demonstrate excellent enhancement factor with the possibility of fast scanning and spatial resolution <12 nm. In fact, each metal nanoisland consists of a multiscale heterostructure that favors large scattering and near-field amplification. Then, we verify the tips to allow challenging nongap-TER spectroscopy on thick biosamples. Our approach introduces a synergistic chemical functionalization of the tips for versatile inclusion and delivery of plasmonic nanoparticles at the tip apex, which may promote the tuning of the plasmonic properties, a large enhancement, and the possibility of adding new degrees of freedom for tip functionalization.

Dietary potential renal Acid load in venezuelan children.

PubMed

López-Sayers, Mayerling; Bernal, Jennifer; López, Michelle

2015-05-01

Our aim was to determine and analyze the dietary PRAL and food composition pattern in apparently healthy children from 1 to 6 years of age. Parents of 52 children were selected by convenience, in an outpatient clinic of healthy children. Dietary quality and pattern was assessed by 24 hour recall and food frequency questionnaire. We focused on the intake of macronutrients and food groups, such as meats, dairy, fruits and vegetables. Nutrient intake was compared with national and international recommendations. PRAL was determined according to the method described by Remer and Manz. Descriptive statistics and correlations were applied. Dietary intake of proteins, milk and meat was high, while fruits and vegetables intake was low. PRAL was positive in 92% of the children and correlated (p<0.05) with intake of energy, proteins, fat, meat and dairy products. Protein intake was above 2.5 g/kg/day in 46.2% of the children. Food groups with the highest unbalance were meat and dairy products for excessive intake and fruits and vegetables regarding low intake, both of which represent risk factors for endogenous acid production. The diet of the children studied was characterized by an excessive acid load with the risk for the generation of systemic acidosis and its metabolic consequences. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Quality factor concept in piezoceramic transformer performance description.

PubMed

Mezheritsky, Alex V

2006-02-01

A new general approach based on the quality factor concept to piezoceramic transformer (PT) performance description is proposed. The system's quality factor, material elastic anisotropy, and coupling factors of the input and output sections of an electrically excited and electrically loaded PT fully characterize its resonance and near-resonance behavior. The PT efficiency, transformation ratio, and input and output power were analytically analyzed and simulated as functions of the load and frequency for the simplest classical Langevin-type and Rosen-type PT designs. A new formulation of the electrical input impedance allows one to separate the power consumed by PT from the power transferred into the load. The system's PT quality factor takes into account losses in each PT "input-output-load" functional components. The loading process is changing PT input electrical impedance on the way that under loading the minimum series impedance is increasing and the maximum parallel impedance is decreasing coincidentally. The quality-factors ratio, between the states of fully loaded and nonloaded PT, is one of the best measures of PTs dynamic performance--practically, the lower the ratio is, the better PT efficiency. A simple and effective method for the loaded PT quality factor determination is proposed. As was found, a piezoceramic with low piezoelectric anisotropy is required to provide maximum PT efficiency and higher corresponding voltage gain. Limitations on the PT output voltage and power, caused by nonlinear effects in piezoceramics, were established.

Influence of track surface on the equine superficial digital flexor tendon loading in two horses at high speed trot.

PubMed

Crevier-Denoix, N; Pourcelot, P; Ravary, B; Robin, D; Falala, S; Uzel, S; Grison, A C; Valette, J P; Denoix, J M; Chateau, H

2009-03-01

Although track surfaces are a risk factor of tendon injuries, their effects on tendon loading at high speed are unknown. Using a noninvasive ultrasonic technique, it is now possible to evaluate the forces in the superficial digital flexor tendon (SDFT) in exercise conditions. To compare the effects of an all-weather waxed track (W) vs. a crushed sand track (S), on the SDFT loading in the trotter horse at high speed. Two trotter horses were equipped with the ultrasonic device (1 MHz ultrasonic probe, fixed on the palmar metacarpal area of the right forelimb). For each trial, data acquisition was made at 400 Hz and 10 consecutive strides were analysed. In each session, the 2 track surfaces were tested in a straight line. The speed was imposed at 10 m/s and recorded. The right forelimb was also equipped with a dynamometric horseshoe and skin markers. The horse was filmed with a high-speed camera (600 Hz); all recordings were synchronised. Statistical differences were tested using the GLM procedure (SAS; P < 0.05). Maximal tendon force was significantly lower on W compared with S. In addition to maximal force peaks around mid-stance, earlier peaks were observed, more pronounced on S than on W, at about 13% (horse 2) and 30% (both horses) of the stance phase. Comparison with kinematic data revealed that these early peaks were accompanied by plateaux in the fetlock angle-time chart. For high tendon forces, the tendon maximal loading rate was significantly lower on W than on S. CONCLUSIONS AND POTENTIAL CLINICAL RELEVANCE: The all-weather waxed track appears to induce a lesser and more gradual SDFT loading than crushed sand. The SDFT loading pattern at high speed trot suggests proximal interphalangeal joint movements during limb loading.

bFGF-containing electrospun gelatin scaffolds with controlled nano-architectural features for directed angiogenesis

PubMed Central

Montero, Ramon B.; Vial, Ximena; Nguyen, Dat Tat; Farhand, Sepehr; Reardon, Mark; Pham, Si M.; Tsechpenakis, Gavriil; Andreopoulos, Fotios M.

2011-01-01

Current therapeutic angiogenesis strategies are focused on the development of biologically responsive scaffolds that can deliver multiple angiogenic cytokines and/or cells in ischemic regions. Herein, we report on a novel electrospinning approach to fabricate cytokine-containing nanofibrous scaffolds with tunable architecture to promote angiogenesis. Fiber diameter and uniformity were controlled by varying the concentration of the polymeric (i.e. gelatin) solution, the feed rate, needle to collector distance, and electric field potential between the collector plate and injection needle. Scaffold fiber orientation (random vs. aligned) was achieved by alternating the polarity of two parallel electrodes placed on the collector plate thus dictating fiber deposition patterns. Basic fibroblast growth factor (bFGF) was physically immobilized within the gelatin scaffolds at variable concentrations and human umbilical vein endothelial cells (HUVEC) were seeded on the top of the scaffolds. Cell proliferation and migration was assessed as a function of growth factor loading and scaffold architecture. HUVECs successfully adhered onto gelatin B scaffolds and cell proliferation was directly proportional to the loading concentrations of the growth factor (0–100 bFGF ng/mL). Fiber orientation had a pronounced effect on cell morphology and orientation. Cells were spread along the fibers of the electrospun scaffolds with the aligned orientation and developed a spindle-like morphology parallel to the scaffold's fibers. In contrast, cells seeded onto the scaffolds with random fiber orientation, did not demonstrate any directionality and appeared to have a rounder shape. Capillary formation (i.e. sprouts length and number of sprouts per bead), assessed in a 3-D in vitro angiogenesis assay, was a function of bFGF loading concentration (0 ng, 50 ng and 100 ng per scaffold) for both types of electrospun scaffolds (i.e. with aligned or random fiber orientation). PMID:22200610

Covariations of eating behaviors with other health-related behaviors among adolescents.

PubMed

Neumark-Sztainer, D; Story, M; Toporoff, E; Himes, J H; Resnick, M D; Blum, R W

1997-06-01

The study objectives are: (1) to examine and compare patterns of covariation of a wide range of health behaviors among adolescent boys and girls; (2) to determine whether eating behaviors are part of a larger construct of health-related behaviors and to identify the behaviors with which they share underlying similarities; and (3) to determine whether youth engaging in other health-compromising behaviors are at risk for unhealthy eating. Data were analyzed from the Minnesota Adolescent Health Survey, a classroom-administered questionnaire, completed by 36,284 adolescents, in grades 7-12 from 1986-87. Among boys, factor analysis revealed five factors: (1) risk-taking behaviors, (2) school-related behaviors, (3) "quietly" disturbed behaviors (e.g., frequent dieting, self-induced vomiting, suicide attempts), (4) health-promoting behaviors; and (5) exercise. Eating behaviors loaded on the construct of health-promoting behaviors with brushing teeth and seat belt use. Among girls, four similar factors emerged; however, exercise loaded on the construct of health-promoting behaviors. Therefore, eating behaviors loaded with brushing teeth, seat belt use, and exercise among girls. Logistic regression analyses, controlling for sociodemographic and personal variables, revealed that boys and girls engaging in health-promoting behaviors were less likely to have unhealthy eating behaviors, while those engaging in quietly disturbed behaviors, risk-taking behaviors, and problematic school behaviors were more likely to have unhealthy eating behaviors. Eating behaviors appear to be part of a health-promoting behavioral construct and should not be viewed in isolation from other behaviors. Although eating behaviors do not appear to be part of the "problem behavior syndrome," youth engaging in a wide range of health-compromising behaviors are at risk for unhealthy eating; emphasizing the need to target high-risk youth with health promotion programs.

[Near infrared reflectance spectroscopy (NIRS): a novel approach to reconstructing historical changes of primary productivity in Antarctic lake].

PubMed

Chen, Qian-Qian; Liu, Xiao-Dong; Liu, Wen-Qi; Jiang, Shan

2011-10-01

Compared with traditional chemical analysis methods, reflectance spectroscopy has the advantages of speed, minimal or no sample preparation, non-destruction, and low cost. In order to explore the potential application of spectroscopy technology in the paleolimnological study on Antarctic lakes, we took a lake sediment core in Mochou Lake at Zhongshan Station of Antarctic, and analyzed the near infrared reflectance spectroscopy (NIRS) data in the sedimentary samples. The results showed that the factor loadings of principal component analysis (PCA) displayed very similar depth-profile change pattern with the S2 index, a reliable proxy for the change in historical lake primary productivity. The correlation analysis showed that the values of PCA factor loading and S2 were correlated significantly, suggesting that it is feasible to infer paleoproductivity changes recorded in Antarctic lakes using NIRS technology. Compared to the traditional method of the trough area between 650 and 700 nm, the authors found that the PCA statistical approach was more accurate for reconstructing the change in historical lake primary productivity. The results reported here demonstrate that reflectance spectroscopy can provide a rapid method for the reconstruction of lake palaeoenviro nmental change in the remote Antarctic regions.

On Wind Forces in the Forest-Edge Region During Extreme-Gust Passages and Their Implications for Damage Patterns

NASA Astrophysics Data System (ADS)

Gromke, Christof; Ruck, Bodo

2018-03-01

A damage pattern that is occasionally found after a period of strong winds shows an area of damaged trees inside a forest stand behind an intact stripe of trees directly at the windward edge. In an effort to understand the mechanism leading to this damage pattern, wind loading in the forest-edge region during passages of extreme gusts with different characteristics are investigated using a scaled forest model in the wind tunnel. The interaction of a transient extreme gust with the stationary atmospheric boundary layer (ABL) as a background flow at the forest edge leads to the formation of a vortex at the top of the canopy. This vortex intensifies when travelling downstream and subsequently deflects high-momentum air from above the canopy downwards resulting in increased wind loading on the tree crowns. Under such conditions, the decrease in wind loading in the streamwise direction can be relatively weak compared to stationary ABL approach flows. The resistance of trees with streamwise distance from the forest edge, however, is the result of adaptive growth to wind loading under stationary flow conditions and shows a rapid decline within two to three tree heights behind the windward edge. For some of the extreme gusts realized, an exceedance of the wind loading over the resistance of the trees is found at approximately three tree heights behind the forest edge, suggesting that the damage pattern described above can be caused by the interaction of a transient extreme gust with the stationary ABL flow.

Foot loading characteristics during three fencing-specific movements.

PubMed

Trautmann, Caroline; Martinelli, Nicolo; Rosenbaum, Dieter

2011-12-01

Plantar pressure characteristics during fencing movements may provide more specific information about the influence of foot loading on overload injury patterns. Twenty-nine experienced fencers participated in the study. Three fencing-specific movements (lunge, advance, retreat) and normal running were performed with three different shoe models: Ballestra (Nike, USA), Adistar Fencing Lo (Adidas, Germany), and the fencers' own shoes. The Pedar system (Novel, Munich, Germany) was used to collect plantar pressures at 50 Hz. Peak pressures, force-time integrals and contact times for five foot regions were compared between four athletic tasks in the lunge leg and supporting leg. Plantar pressure analysis revealed characteristic pressure distribution patterns for the fencing movements. For the lunge leg, during the lunge and advance movements the heel is predominantly loaded; during retreat, it is the hallux. For the supporting leg, during the lunge and advance movements the forefoot is predominantly loaded; during retreat, it is the hallux. Fencing-specific movements load the plantar surface in a distinct way compared with running. An effective cushioning in the heel and hallux region would help to minimize foot loading during fencing-specific movements.

Nutrition in Diabetes.

PubMed

Hamdy, Osama; Barakatun-Nisak, Mohd-Yusof

2016-12-01

Medical nutrition therapy (MNT) is a key component of diabetes management. The importance of balancing macronutrients, reducing carbohydrate load, lowering glycemic index, and implementing an overall healthy dietary pattern are emerging as better approaches for MNT in diabetes. Recent research points to improved glycemic control, reduction in body weight, and improvement in many cardiovascular risk factors when these approaches are provided by registered dietitians or health care providers. This review article discusses the current evidence about the role of sensible nutrition in diabetes management. Specific eating plans for weight reduction and for patients with type 1 diabetes are also discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

Virtual Genomes in Flux: An Interplay of Neutrality and Adaptability Explains Genome Expansion and Streamlining

PubMed Central

Cuypers, Thomas D.; Hogeweg, Paulien

2012-01-01

The picture that emerges from phylogenetic gene content reconstructions is that genomes evolve in a dynamic pattern of rapid expansion and gradual streamlining. Ancestral organisms have been estimated to possess remarkably rich gene complements, although gene loss is a driving force in subsequent lineage adaptation and diversification. Here, we study genome dynamics in a model of virtual cells evolving to maintain homeostasis. We observe a pattern of an initial rapid expansion of the genome and a prolonged phase of mutational load reduction. Generally, load reduction is achieved by the deletion of redundant genes, generating a streamlining pattern. Load reduction can also occur as a result of the generation of highly neutral genomic regions. These regions can expand and contract in a neutral fashion. Our study suggests that genome expansion and streamlining are generic patterns of evolving systems. We propose that the complex genotype to phenotype mapping in virtual cells as well as in their biological counterparts drives genome size dynamics, due to an emerging interplay between adaptation, neutrality, and evolvability. PMID:22234601

Watershed-based sources of polycyclic aromatic hydrocarbons in urban storm water.

PubMed

Stein, Eric D; Tiefenthaler, Liesl L; Schiff, Kenneth

2006-02-01

Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic and mutagenic compounds, ubiquitous in the air and water of urban environments, and have been shown to accumulate in coastal estuarine and marine sediments. Although previous studies have documented concentrations and loads of PAHs in urban runoff, little is known about the sources and temporal patterns of PAH loading from storm water. This study characterized the sources and temporal patterns of PAHs in urban storm water by analyzing PAH concentrations and loads from a range of homogeneous land use sites and in-river mass emission sites throughout the greater Los Angeles, California, USA, region. Samples were collected at 30- to 60-min intervals over the course of a storm during multiple storm events over a four-year period in order to investigate PAH sources and inter- and intrastorm patterns in loading. Polycyclic aromatic hydrocarbon storm fluxes ranged from 1.3 g/km2 for the largely undeveloped Arroyo Sequit watershed to 223.7 g/km2 for the highly urbanized Verdugo Wash watershed, with average storm fluxes being 46 times higher in developed versus undeveloped watersheds. Early-season storms repeatedly produced substantially higher loads than comparably sized late-season storms. Within individual storms, PAHs exhibited a moderate first flush with between 30 and 60% of the total PAH load being discharged in the first 20% of the storm volume. The relative distribution of individual PAHs demonstrated a consistent predominance of high-molecular-weight compounds indicative of pyrogenic sources.

High-frequency AC/DC converter with unity power factor and minimum harmonic distortion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wernekinch, E.R.

1987-01-01

The power factor is controlled by adjusting the relative position of the fundamental component of an optimized PWM-type voltage with respect to the supply voltage. Current harmonic distortion is minimized by the use of optimized firing angles for the converter at a frequency where GTO's can be used. This feature makes this approach very attractive at power levels of 100 to 600 kW. To obtain the optimized PWM pattern, a steepest descent digital computer algorithm is used. Digital-computer simulations are performed and a low-power model is constructed and tested to verify the concepts and the behavior of the model. Experimentalmore » results show that unity power factor is achieved and that the distortion in the phase currents is 10.4% at 90% of full load. This is less than achievable with sinusoidal PWM, harmonic elimination, hysteresis control, and deadbeat control for the same switching frequency.« less

Impact of ballistic body armour and load carriage on walking patterns and perceived comfort.

PubMed

Park, Huiju; Branson, Donna; Petrova, Adriana; Peksoz, Semra; Jacobson, Bert; Warren, Aric; Goad, Carla; Kamenidis, Panagiotis

2013-01-01

This study investigated the impact of weight magnitude and distribution of body armour and carrying loads on military personnel's walking patterns and comfort perceptions. Spatio-temporal parameters of walking, plantar pressure and contact area were measured while seven healthy male right-handed military students wore seven different garments of varying weight (0.06, 9, 18 and 27 kg) and load distribution (balanced and unbalanced, on the front and back torso). Higher weight increased the foot contact time with the floor. In particular, weight placement on the non-dominant side of the front torso resulted in the greatest stance phase and double support. Increased plantar pressure and contact area observed during heavier loads entail increased impact forces, which can cause overuse injuries and foot blisters. Participants reported increasingly disagreeable pressure and strain in the shoulder, neck and lower back during heavier weight conditions and unnatural walking while wearing unbalanced weight distributed loads. This study shows the potentially synergistic impact of wearing body armour vest with differential loads on body movement and comfort perception. This study found that soldiers should balance loads, avoiding load placement on the non-dominant side front torso, thus minimising mobility restriction and potential injury risk. Implications for armour vest design modifications can also be found in the results.

Impact of measurement uncertainty from experimental load distribution factors on bridge load rating

NASA Astrophysics Data System (ADS)

Gangone, Michael V.; Whelan, Matthew J.

2018-03-01

Load rating and testing of highway bridges is important in determining the capacity of the structure. Experimental load rating utilizes strain transducers placed at critical locations of the superstructure to measure normal strains. These strains are then used in computing diagnostic performance measures (neutral axis of bending, load distribution factor) and ultimately a load rating. However, it has been shown that experimentally obtained strain measurements contain uncertainties associated with the accuracy and precision of the sensor and sensing system. These uncertainties propagate through to the diagnostic indicators that in turn transmit into the load rating calculation. This paper will analyze the effect that measurement uncertainties have on the experimental load rating results of a 3 span multi-girder/stringer steel and concrete bridge. The focus of this paper will be limited to the uncertainty associated with the experimental distribution factor estimate. For the testing discussed, strain readings were gathered at the midspan of each span of both exterior girders and the center girder. Test vehicles of known weight were positioned at specified locations on each span to generate maximum strain response for each of the five girders. The strain uncertainties were used in conjunction with a propagation formula developed by the authors to determine the standard uncertainty in the distribution factor estimates. This distribution factor uncertainty is then introduced into the load rating computation to determine the possible range of the load rating. The results show the importance of understanding measurement uncertainty in experimental load testing.

Electricity forecasting on the individual household level enhanced based on activity patterns

PubMed Central

Gajowniczek, Krzysztof; Ząbkowski, Tomasz

2017-01-01

Leveraging smart metering solutions to support energy efficiency on the individual household level poses novel research challenges in monitoring usage and providing accurate load forecasting. Forecasting electricity usage is an especially important component that can provide intelligence to smart meters. In this paper, we propose an enhanced approach for load forecasting at the household level. The impacts of residents’ daily activities and appliance usages on the power consumption of the entire household are incorporated to improve the accuracy of the forecasting model. The contributions of this paper are threefold: (1) we addressed short-term electricity load forecasting for 24 hours ahead, not on the aggregate but on the individual household level, which fits into the Residential Power Load Forecasting (RPLF) methods; (2) for the forecasting, we utilized a household specific dataset of behaviors that influence power consumption, which was derived using segmentation and sequence mining algorithms; and (3) an extensive load forecasting study using different forecasting algorithms enhanced by the household activity patterns was undertaken. PMID:28423039

Electricity forecasting on the individual household level enhanced based on activity patterns.

PubMed

Gajowniczek, Krzysztof; Ząbkowski, Tomasz

2017-01-01

Leveraging smart metering solutions to support energy efficiency on the individual household level poses novel research challenges in monitoring usage and providing accurate load forecasting. Forecasting electricity usage is an especially important component that can provide intelligence to smart meters. In this paper, we propose an enhanced approach for load forecasting at the household level. The impacts of residents' daily activities and appliance usages on the power consumption of the entire household are incorporated to improve the accuracy of the forecasting model. The contributions of this paper are threefold: (1) we addressed short-term electricity load forecasting for 24 hours ahead, not on the aggregate but on the individual household level, which fits into the Residential Power Load Forecasting (RPLF) methods; (2) for the forecasting, we utilized a household specific dataset of behaviors that influence power consumption, which was derived using segmentation and sequence mining algorithms; and (3) an extensive load forecasting study using different forecasting algorithms enhanced by the household activity patterns was undertaken.

Pathways to substance-related disorder: a structural model approach exploring the influence of temperament, character, and childhood adversity in a national cohort of prisoners.

PubMed

Lukasiewicz, Michael; Neveu, Xavier; Blecha, Lisa; Falissard, Bruno; Reynaud, Michel; Gasquet, Isabelle

2008-01-01

Using Cloninger's model of personality, we aimed to specify the relative influence of the more biologically determined variables, temperament and character and more environmentally driven influence, childhood adversity in the development of addiction; and to compare patterns found among alcoholics with those found among drug addicts. We studied a group of prisoners, at a high risk of substance abuse and past history of childhood adversity. Using a stratified random strategy we selected (i) 23 prisons among the different types of prison in France, (ii) 998 prisoners. Each prisoner was assessed by two psychiatrists--one junior, using a structured interview (MINI 5 plus), and one senior, completing the procedure with an open clinical interview. At the end of the interview the clinicians met and agreed on a list of diagnoses. Cloninger's Temperament and Character Inventory was used to measure personality. Structural equations models, which have been advocated to disentangle the respective influence of complex risk factors, were used. The "novelty seeking" temperament was a crucial vulnerability factor, for both alcoholics and drug addicts, in the same proportion. Character and childhood adversity played a significant part only in the development of drug abuse. In a prison population, a common biological loaded factor, novelty seeking is found both at the core of alcohol- and drug-related disorder whereas environmentally loaded factors play a greater role in drug problems.

Impact of the rainfall pattern on synthetic pesticides and copper runoff from a vineyard catchment

NASA Astrophysics Data System (ADS)

Payraudeau, Sylvain; Meite, Fatima; Wiegert, Charline; Imfeld, Gwenaël

2017-04-01

Runoff is a major process of pesticide transport from agricultural land to downstream aquatic ecosystems. The impact of rainfall characteristics on the transport of runoff-related pesticide is rarely evaluated at the catchment scale. Here, we evaluate the influence of rainfall pattern on the mobilization of synthetic pesticides and copper fungicides in runoff from a small vineyard catchment, both at the plot and catchment scales. During two vineyard growing seasons in 2015 and 2016 (from March to October), we monitored rainfall, runoff, and concentrations of copper and 20 fungicides and herbicides applied by winegrowers at the Rouffach vineyard catchment (France, Alsace; 42.5 ha). Rainfall data were recorded within the catchment while runoff measurement and flow-proportional water sampling were carried out at the outlet of the plot (1486 m2; 87.5 × 17 m) and the catchment. In total, discharges of the 14 runoff events were continuously monitored between March and October 2015 using bubbler flow modules combined with Venturi channels. Detailed and distributed dataset on pesticide applications were extracted from survey (copper formulations and type of pesticides, amount and application dates). Pools of copper and synthetic pesticides were quantified weekly in the topsoil (0-3 cm) by systematic sampling across the catchment. The concentrations of copper (10 mg.kg-1 dried soil) and synthetic pesticides (close to the quantification limit, i.e. 0.05 µg.L-1) available in the top soil for off-site transport largely differed over time. Between March and October, an accumulation of copper of 10% was observed in the top-soil while pesticide concentration decreased below the quantification limits after a few days or weeks following application, depending of the compounds. The average runoff generated at the plot scale was very low (0.13% ± 0.30). The maximum runoff reached 1.37% during the storm of July 22, 2015. Synthetic pesticides exported by runoff was less than 1‰ of the applications. The copper mass exported represented about 1% (i.e. 2,085 g at the plot's scale) of the seasonal input, and mainly occurred during the major storm event. Copper were mainly exported in association with suspended particulate matter (SPM) (>80% of the total load). The partitioning between dissolved and SPM phases differs for the synthetic pesticides as expected by their properties. The rainfall pattern influences concentrations and loads of copper and the pesticides. Dissolved pesticide loads normalized by the pesticide mass in soil varied with larger rainfall intensities, runoff discharges and volumes. Contrasted relationships between rainfall characteristics (i.e. intensity, duration and total amount) and the load exported suggest that mechanisms of contaminant delivery from the vineyard soil differs among the pesticides and for copper. The results support the idea that, even in small catchment areas, the rainfall pattern (i.e. rainfall intensity and duration) partly controls the transport of pesticide and copper loads in runoff. Though other factors, such as the chemical characteristics and the amount and timing of applications, are important drivers for pesticide runoff, the rainfall patterns also determine the transport of pesticides from catchment to downstream aquatic ecosystems, and thus the ecotoxicological risk.

Factor structure and individual patterns of DSM-IV conduct disorder criteria in adolescent psychiatric inpatients.

PubMed

Janson, Harald; Kjelsberg, Ellen

2006-01-01

We investigated the factor structure of the DSM-IV conduct disorder (CD) diagnostic criteria and typical individual patterns of CD subscales in an adolescent inpatient population using detailed hospital records of a Norwegian nationwide sample of 1087 adolescent psychiatric inpatients scored for the 15 DSM-IV CD criteria. Varimax rotated principal components and full-information factor analyses of 12 CD criteria were carried out separately for boys and girls employing two methods. Standardized values on three subscales of CD criteria were subjected to Ward's method of hierarchical cluster analyses followed by k-means relocation employing a double cross-replication design. Similar factor structures emerged regardless of factoring method and gender. With the exception of Criteria 8 ("Fire setting") and 14 ("Run away from home") the factor loadings for both genders were in accordance with Loeber's tripartite model, with Aggression, Delinquency, and Rule Breaking factors largely corresponding to Loeber's overt, covert and authority conflict pathways. A five-cluster solution proved highly replicable and interpretable. One cluster gathered adolescents without CD, and the remaining four described groups with different conceptually meaningful constellations of CD criteria, which were not equally prevalent in each gender. Delinquency appeared in all symptomatic clusters. The cluster analytic results highlighted typical forms of expressions of conduct problems, and the fact that these forms may not be equally prevalent in girls and boys even while the underlying structure of conduct problems may be similar across genders. Future research should address the prediction of specific outcomes from CD criteria subscales or constellations.

Evaluating measurement invariance across assessment modes of phone interview and computer self-administered survey for the PROMIS measures in a population-based cohort of localized prostate cancer survivors.

PubMed

Wang, Mian; Chen, Ronald C; Usinger, Deborah S; Reeve, Bryce B

2017-11-01

To evaluate measurement invariance (phone interview vs computer self-administered survey) of 15 PROMIS measures responded by a population-based cohort of localized prostate cancer survivors. Participants were part of the North Carolina Prostate Cancer Comparative Effectiveness and Survivorship Study. Out of the 952 men who took the phone interview at 24 months post-treatment, 401 of them also completed the same survey online using a home computer. Unidimensionality of the PROMIS measures was examined using single-factor confirmatory factor analysis (CFA) models. Measurement invariance testing was conducted using longitudinal CFA via a model comparison approach. For strongly or partially strongly invariant measures, changes in the latent factors and factor autocorrelations were also estimated and tested. Six measures (sleep disturbance, sleep-related impairment, diarrhea, illness impact-negative, illness impact-positive, and global satisfaction with sex life) had locally dependent items, and therefore model modifications had to be made on these domains prior to measurement invariance testing. Overall, seven measures achieved strong invariance (all items had equal loadings and thresholds), and four measures achieved partial strong invariance (each measure had one item with unequal loadings and thresholds). Three measures (pain interference, interest in sexual activity, and global satisfaction with sex life) failed to establish configural invariance due to between-mode differences in factor patterns. This study supports the use of phone-based live interviewers in lieu of PC-based assessment (when needed) for many of the PROMIS measures.

Assessment of reliability of CAD-CAM tooth-colored implant custom abutments.

PubMed

Guilherme, Nuno Marques; Chung, Kwok-Hung; Flinn, Brian D; Zheng, Cheng; Raigrodski, Ariel J

2016-08-01

Information is lacking about the fatigue resistance of computer-aided design and computer-aided manufacturing (CAD-CAM) tooth-colored implant custom abutment materials. The purpose of this in vitro study was to investigate the reliability of different types of CAD-CAM tooth-colored implant custom abutments. Zirconia (Lava Plus), lithium disilicate (IPS e.max CAD), and resin-based composite (Lava Ultimate) abutments were fabricated using CAD-CAM technology and bonded to machined titanium-6 aluminum-4 vanadium (Ti-6Al-4V) alloy inserts for conical connection implants (NobelReplace Conical Connection RP 4.3×10 mm; Nobel Biocare). Three groups (n=19) were assessed: group ZR, CAD-CAM zirconia/Ti-6Al-4V bonded abutments; group RC, CAD-CAM resin-based composite/Ti-6Al-4V bonded abutments; and group LD, CAD-CAM lithium disilicate/Ti-6Al-4V bonded abutments. Fifty-seven implant abutments were secured to implants and embedded in autopolymerizing acrylic resin according to ISO standard 14801. Static failure load (n=5) and fatigue failure load (n=14) were tested. Weibull cumulative damage analysis was used to calculate step-stress reliability at 150-N and 200-N loads with 2-sided 90% confidence limits. Representative fractured specimens were examined using stereomicroscopy and scanning electron microscopy to observe fracture patterns. Weibull plots revealed β values of 2.59 for group ZR, 0.30 for group RC, and 0.58 for group LD, indicating a wear-out or cumulative fatigue pattern for group ZR and load as the failure accelerating factor for groups RC and LD. Fractographic observation disclosed that failures initiated in the interproximal area where the lingual tensile stresses meet the compressive facial stresses for the early failure specimens. Plastic deformation of titanium inserts with fracture was observed for zirconia abutments in fatigue resistance testing. Significantly higher reliability was found in group ZR, and no significant differences in reliability were determined between groups RC and LD. Differences were found in the failure characteristics of group ZR between static and fatigue loading. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Indoor air bacterial load and antibiotic susceptibility pattern of isolates in operating rooms and surgical wards at jimma university specialized hospital, southwest ethiopia.

PubMed

Genet, Chalachew; Kibru, Gebre; Tsegaye, Wondewosen

2011-03-01

Surgical site infection is the second most common health care associated infection. One of the risk factors for such infection is bacterial contamination of operating rooms' and surgical wards' indoor air. In view of that, the microbiological quality of air can be considered as a mirror of the hygienic condition of these rooms. Thus, the objective of this study was to determine the bacterial load and antibiotic susceptibility pattern of isolates in operating rooms' and surgical wards' indoor air of Jimma University Specialized Hospital. A cross sectional study was conducted to measure indoor air microbial quality of operating rooms and surgical wards from October to January 2009/2010 on 108 indoor air samples collected in twelve rounds using purposive sampling technique by Settle Plate Method (Passive Air Sampling following 1/1/1 Schedule). Sample processing and antimicrobial susceptibility testing were done following standard bacteriological techniques. The data was analyzed using SPSS version 16 and interpreted according to scientifically determined baseline values initially suggested by Fisher. The mean aerobic colony counts obtained in OR-1(46cfu/hr) and OR-2(28cfu/hr) was far beyond the set 5-8cfu/hr acceptable standards for passive room. Similarly the highest mean aerobic colony counts of 465cfu/hr and 461cfu/hr were observed in Female room-1 and room-2 respectively when compared to the acceptable range of 250-450cfu/hr. In this study only 3 isolates of S. pyogenes and 48 isolates of S. aureus were identified. Over 66% of S. aureus was identified in Critical Zone of Operating rooms. All isolates of S. aureus showed 100% and 82.8% resistance to methicillin and ampicillin respectively. Higher degree of aerobic bacterial load was measured from operating rooms' and surgical wards' indoor air. Reducing foot trafficking, improving the ventilation system and routine cleaning has to be made to maintain the aerobic bacteria load with in optimal level.

Speech perception and phonological short-term memory capacity in language impairment: preliminary evidence from adolescents with specific language impairment (SLI) and autism spectrum disorders (ASD).

PubMed

Loucas, Tom; Riches, Nick Greatorex; Charman, Tony; Pickles, Andrew; Simonoff, Emily; Chandler, Susie; Baird, Gillian

2010-01-01

The cognitive bases of language impairment in specific language impairment (SLI) and autism spectrum disorders (ASD) were investigated in a novel non-word comparison task which manipulated phonological short-term memory (PSTM) and speech perception, both implicated in poor non-word repetition. This study aimed to investigate the contributions of PSTM and speech perception in non-word processing and whether individuals with SLI and ASD plus language impairment (ALI) show similar or different patterns of deficit in these cognitive processes. Three groups of adolescents (aged 14-17 years), 14 with SLI, 16 with ALI, and 17 age and non-verbal IQ matched typically developing (TD) controls, made speeded discriminations between non-word pairs. Stimuli varied in PSTM load (two- or four-syllables) and speech perception load (mismatches on a word-initial or word-medial segment). Reaction times showed effects of both non-word length and mismatch position and these factors interacted: four-syllable and word-initial mismatch stimuli resulted in the slowest decisions. Individuals with language impairment showed the same pattern of performance as those with typical development in the reaction time data. A marginal interaction between group and item length was driven by the SLI and ALI groups being less accurate with long items than short ones, a difference not found in the TD group. Non-word discrimination suggests that there are similarities and differences between adolescents with SLI and ALI and their TD peers. Reaction times appear to be affected by increasing PSTM and speech perception loads in a similar way. However, there was some, albeit weaker, evidence that adolescents with SLI and ALI are less accurate than TD individuals, with both showing an effect of PSTM load. This may indicate, at some level, the processing substrate supporting both PSTM and speech perception is intact in adolescents with SLI and ALI, but also in both there may be impaired access to PSTM resources.

A continuous time-resolved measure decoded from EEG oscillatory activity predicts working memory task performance.

PubMed

Astrand, Elaine

2018-06-01

Working memory (WM), crucial for successful behavioral performance in most of our everyday activities, holds a central role in goal-directed behavior. As task demands increase, inducing higher WM load, maintaining successful behavioral performance requires the brain to work at the higher end of its capacity. Because it is depending on both external and internal factors, individual WM load likely varies in a continuous fashion. The feasibility to extract such a continuous measure in time that correlates to behavioral performance during a working memory task remains unsolved. Multivariate pattern decoding was used to test whether a decoder constructed from two discrete levels of WM load can generalize to produce a continuous measure that predicts task performance. Specifically, a linear regression with L2-regularization was chosen with input features from EEG oscillatory activity recorded from healthy participants while performing the n-back task, [Formula: see text]. The feasibility to extract a continuous time-resolved measure that correlates positively to trial-by-trial working memory task performance is demonstrated (r  =  0.47, p  <  0.05). It is furthermore shown that this measure allows to predict task performance before action (r  =  0.49, p  <  0.05). We show that the extracted continuous measure enables to study the temporal dynamics of the complex activation pattern of WM encoding during the n-back task. Specifically, temporally precise contributions of different spectral features are observed which extends previous findings of traditional univariate approaches. These results constitute an important contribution towards a wide range of applications in the field of cognitive brain-machine interfaces. Monitoring mental processes related to attention and WM load to reduce the risk of committing errors in high-risk environments could potentially prevent many devastating consequences or using the continuous measure as neurofeedback opens up new possibilities to develop novel rehabilitation techniques for individuals with degraded WM capacity.

A continuous time-resolved measure decoded from EEG oscillatory activity predicts working memory task performance

NASA Astrophysics Data System (ADS)

Astrand, Elaine

2018-06-01

Objective. Working memory (WM), crucial for successful behavioral performance in most of our everyday activities, holds a central role in goal-directed behavior. As task demands increase, inducing higher WM load, maintaining successful behavioral performance requires the brain to work at the higher end of its capacity. Because it is depending on both external and internal factors, individual WM load likely varies in a continuous fashion. The feasibility to extract such a continuous measure in time that correlates to behavioral performance during a working memory task remains unsolved. Approach. Multivariate pattern decoding was used to test whether a decoder constructed from two discrete levels of WM load can generalize to produce a continuous measure that predicts task performance. Specifically, a linear regression with L2-regularization was chosen with input features from EEG oscillatory activity recorded from healthy participants while performing the n-back task, n\\in [1,2] . Main results. The feasibility to extract a continuous time-resolved measure that correlates positively to trial-by-trial working memory task performance is demonstrated (r  =  0.47, p  <  0.05). It is furthermore shown that this measure allows to predict task performance before action (r  =  0.49, p  <  0.05). We show that the extracted continuous measure enables to study the temporal dynamics of the complex activation pattern of WM encoding during the n-back task. Specifically, temporally precise contributions of different spectral features are observed which extends previous findings of traditional univariate approaches. Significance. These results constitute an important contribution towards a wide range of applications in the field of cognitive brain–machine interfaces. Monitoring mental processes related to attention and WM load to reduce the risk of committing errors in high-risk environments could potentially prevent many devastating consequences or using the continuous measure as neurofeedback opens up new possibilities to develop novel rehabilitation techniques for individuals with degraded WM capacity.

Factors controlling the long-term temporal and spatial patterns of nitrate-nitrogen export in a dairy farming watershed.

PubMed

Jiang, Rui; Wang, Chun-ying; Hatano, Ryusuke; Kuramochi, Kanta; Hayakawa, Atsushi; Woli, Krishna P

2015-04-01

It is difficult to investigate the factors that control the riverine nitrate-nitrogen (NO3--N) export in a watershed which gains or losses groundwater. To control the NO3--N contamination in these watersheds, it is necessary to investigate the factors that are related to the export of NO3--N that is only produced by the watershed itself. This study was conducted in the Shibetsu watershed located in eastern Hokkaido, Japan, which gains external groundwater contribution (EXT) and 34% of the annual NO3--N loading occurs through EXT. The riverine NO3--N exports from 1980 to 2009 were simulated by the SWAT model, and the factors controlling the temporal and spatial patterns of NO3--N exports were investigated without considering the EXT. The results show that hydrological events control NO3--N export at the seasonal scale, while the hydrological and biogeochemical processes are likely to control NO3--N export at the annual scale. There was an integrated effect among the land use, topography, and soil type related to denitrification process, that regulated the spatial patterns of NO3--N export. The spatial distribution of NO3--N export from hydrologic response units (HRUs) identified the agricultural areas with surplus N that are vulnerable to nitrate contamination. A new standard for the N fertilizer application rate including manure application should be given to control riverine NO3--N export. This study demonstrates that applying the SWAT model is an appropriate method to determine the temporal and spatial patterns of NO3--N export from the watershed which includes EXT and to identify the crucial pollution areas within a watershed in which the management practices can be improved to more effectively control NO3--N export to water bodies.

Fundamental concepts of structural loading and load relief techniques for the space shuttle

NASA Technical Reports Server (NTRS)

Ryan, R. S.; Mowery, D. K.; Winder, S. W.

1972-01-01

The prediction of flight loads and their potential reduction, using various control system logics for the space shuttle vehicles, is discussed. Some factors not found on previous launch vehicles that increase the complexity are large lifting surfaces, unsymmetrical structure, unsymmetrical aerodynamics, trajectory control system coupling, and large aeroelastic effects. These load-producing factors and load-reducing techniques are analyzed.

Dietary patterns in obese pregnant women; influence of a behavioral intervention of diet and physical activity in the UPBEAT randomized controlled trial.

PubMed

Flynn, Angela C; Seed, Paul T; Patel, Nashita; Barr, Suzanne; Bell, Ruth; Briley, Annette L; Godfrey, Keith M; Nelson, Scott M; Oteng-Ntim, Eugene; Robinson, Sian M; Sanders, Thomas A; Sattar, Naveed; Wardle, Jane; Poston, Lucilla; Goff, Louise M

2016-11-29

Understanding dietary patterns in obese pregnant women will inform future intervention strategies to improve pregnancy outcomes and the health of the child. The aim of this study was to investigate the effect of a behavioral intervention of diet and physical activity advice on dietary patterns in obese pregnant woman participating in the UPBEAT study, and to explore associations of dietary patterns with pregnancy outcomes. In the UPBEAT randomized controlled trial, pregnant obese women from eight UK multi-ethnic, inner-city populations were randomly assigned to receive a diet/physical activity intervention or standard antenatal care. The dietary intervention aimed to reduce glycemic load and saturated fat intake. Diet was assessed using a food frequency questionnaire (FFQ) at baseline (15 +0 -18 +6 weeks' gestation), post intervention (27 +0 -28 +6 weeks) and in late pregnancy (34 +0 -36 +0 weeks). Dietary patterns were characterized using factor analysis of the baseline FFQ data, and changes compared in the control and intervention arms. Patterns were related to pregnancy outcomes in the combined control/intervention cohort (n = 1023). Four distinct baseline dietary patterns were defined; Fruit and vegetables, African/Caribbean, Processed, and Snacks, which were differently associated with social and demographic factors. The UPBEAT intervention significantly reduced the Processed (-0.14; 95% CI -0.19, -0.08, P <0.0001) and Snacks (-0.24; 95% CI -0.31, -0.17, P <0.0001) pattern scores. In the adjusted model, baseline scores for the African/Caribbean (quartile 4 compared with quartile 1: OR = 2.46; 95% CI 1.41, 4.30) and Processed (quartile 4 compared with quartile 1: OR = 2.05; 95% CI 1.23, 3.41) patterns in the entire cohort were associated with increased risk of gestational diabetes. In a diverse cohort of obese pregnant women an intensive dietary intervention improved Processed and Snack dietary pattern scores. African/Caribbean and Processed patterns were associated with an increased risk of gestational diabetes, and provide potential targets for future interventions. Current controlled trials; ISRCTN89971375.

Measurement Invariance and the Five-Factor Model of Personality: Asian International and Euro American Cultural Groups.

PubMed

Rollock, David; Lui, P Priscilla

2016-10-01

This study examined measurement invariance of the NEO Five-Factor Inventory (NEO-FFI), assessing the five-factor model (FFM) of personality among Euro American (N = 290) and Asian international (N = 301) students (47.8% women, Mage = 19.69 years). The full 60-item NEO-FFI data fit the expected five-factor structure for both groups using exploratory structural equation modeling, and achieved configural invariance. Only 37 items significantly loaded onto the FFM-theorized factors for both groups and demonstrated metric invariance. Threshold invariance was not supported with this reduced item set. Groups differed the most in the item-factor relationships for Extraversion and Agreeableness, as well as in response styles. Asian internationals were more likely to use midpoint responses than Euro Americans. While the FFM can characterize broad nomothetic patterns of personality traits, metric invariance with only the subset of NEO-FFI items identified limits direct group comparisons of correlation coefficients among personality domains and with other constructs, and of mean differences on personality domains. © The Author(s) 2015.

14 CFR 25.527 - Hull and main float load factors.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hull and main float load factors. 25.527... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Water Loads § 25.527 Hull and main... 1=empirical hull station weighing factor, in accordance with figure 2 of appendix B. (7) r x=ratio...

Testing Measurement Invariance Using MIMIC: Likelihood Ratio Test with a Critical Value Adjustment

ERIC Educational Resources Information Center

Kim, Eun Sook; Yoon, Myeongsun; Lee, Taehun

2012-01-01

Multiple-indicators multiple-causes (MIMIC) modeling is often used to test a latent group mean difference while assuming the equivalence of factor loadings and intercepts over groups. However, this study demonstrated that MIMIC was insensitive to the presence of factor loading noninvariance, which implies that factor loading invariance should be…

Measurement of inspiratory muscle performance with incremental threshold loading: a comparison of two techniques.

PubMed Central

Bardsley, P A; Bentley, S; Hall, H S; Singh, S J; Evans, D H; Morgan, M D

1993-01-01

BACKGROUND--Incremental threshold loading (ITL) is a test of inspiratory muscle performance which is usually performed by breathing through a weighted inspiratory plunger, the load on the inspiratory muscles being increased by externally adding weights to the intake valve. This is not a true threshold device and may be inaccurate. This method was compared with a true threshold device consisting of a solenoid valve which only opens to supply air at a predetermined negative mouth pressure. METHODS--Six naive, normal subjects (three men and three women) aged 22-24 years underwent three tests using each system. The inspiratory loads were increased every minute by equivalent amounts, -10 cm H2O with the solenoid valve and by 50 g with the weighted plunger, until the subjects could not inspire or sustain inspiration for a full minute. Six experienced subjects (four men and two women) aged 23-41 years were subsequently randomised to perform ITL with the solenoid valve, twice with the breathing pattern fixed and twice free. RESULTS--The solenoid valve generated a more accurate mouth pressure response and was less variable at higher loads than the weighted plunger. The work performed (expressed as the pressure-time product) was less with the solenoid valve but was more reproducible. ITL with the solenoid valve was not influenced by controlling the breathing pattern of the subjects. CONCLUSIONS--The solenoid valve has several features that make it superior to the weighted plunger as a device for ITL. It generates a more accurate mouth pressure response which is less variable at higher loads. Increases in load are smoother and quicker to introduce. ITL with the solenoid valve is not influenced by varying breathing patterns and does not require any external regulation. PMID:8511732

Measurement of inspiratory muscle performance with incremental threshold loading: a comparison of two techniques.

PubMed

Bardsley, P A; Bentley, S; Hall, H S; Singh, S J; Evans, D H; Morgan, M D

1993-04-01

Incremental threshold loading (ITL) is a test of inspiratory muscle performance which is usually performed by breathing through a weighted inspiratory plunger, the load on the inspiratory muscles being increased by externally adding weights to the intake valve. This is not a true threshold device and may be inaccurate. This method was compared with a true threshold device consisting of a solenoid valve which only opens to supply air at a predetermined negative mouth pressure. Six naive, normal subjects (three men and three women) aged 22-24 years underwent three tests using each system. The inspiratory loads were increased every minute by equivalent amounts, -10 cm H2O with the solenoid valve and by 50 g with the weighted plunger, until the subjects could not inspire or sustain inspiration for a full minute. Six experienced subjects (four men and two women) aged 23-41 years were subsequently randomised to perform ITL with the solenoid valve, twice with the breathing pattern fixed and twice free. The solenoid valve generated a more accurate mouth pressure response and was less variable at higher loads than the weighted plunger. The work performed (expressed as the pressure-time product) was less with the solenoid valve but was more reproducible. ITL with the solenoid valve was not influenced by controlling the breathing pattern of the subjects. The solenoid valve has several features that make it superior to the weighted plunger as a device for ITL. It generates a more accurate mouth pressure response which is less variable at higher loads. Increases in load are smoother and quicker to introduce. ITL with the solenoid valve is not influenced by varying breathing patterns and does not require any external regulation.

Age Differentiation within Gray Matter, White Matter, and between Memory and White Matter in an Adult Life Span Cohort.

PubMed

de Mooij, Susanne M M; Henson, Richard N A; Waldorp, Lourens J; Kievit, Rogier A

2018-06-20

It is well established that brain structures and cognitive functions change across the life span. A long-standing hypothesis called "age differentiation" additionally posits that the relations between cognitive functions also change with age. To date, however, evidence for age-related differentiation is mixed, and no study has examined differentiation of the relationship between brain and cognition. Here we use multigroup structural equation models (SEMs) and SEM trees to study differences within and between brain and cognition across the adult life span (18-88 years) in a large ( N > 646, closely matched across sexes), population-derived sample of healthy human adults from the Cambridge Centre for Ageing and Neuroscience (www.cam-can.org). After factor analyses of gray matter volume (from T1- and T2-weighted MRI) and white matter organization (fractional anisotropy from diffusion-weighted MRI), we found evidence for the differentiation of gray and white matter, such that the covariance between brain factors decreased with age. However, we found no evidence for age differentiation among fluid intelligence, language, and memory, suggesting a relatively stable covariance pattern among cognitive factors. Finally, we observed a specific pattern of age differentiation between brain and cognitive factors, such that a white matter factor, which loaded most strongly on the hippocampal cingulum, became less correlated with memory performance in later life. These patterns are compatible with the reorganization of cognitive functions in the face of neural decline, and/or with the emergence of specific subpopulations in old age. SIGNIFICANCE STATEMENT The theory of age differentiation posits age-related changes in the relationships among cognitive domains, either weakening (differentiation) or strengthening (dedifferentiation), but evidence for this hypothesis is mixed. Using age-varying covariance models in a large cross-sectional adult life span sample, we found age-related reductions in the covariance among both brain measures (neural differentiation), but no covariance change among cognitive factors of fluid intelligence, language, and memory. We also observed evidence of uncoupling (differentiation) between a white matter factor and cognitive factors in older age, most strongly for memory. Together, our findings support age-related differentiation as a complex, multifaceted pattern that differs for brain and cognition, and discuss several mechanisms that might explain the changing relationship between brain and cognition. Copyright © 2018 de Mooij et al.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sanquist, Thomas F.; Mahy, Heidi A.; Morris, Fred A.

Understanding the issues surrounding public acceptance of homeland security systems is important for balancing security needs and potential civil liberties infringements. A psychometric survey was used to measure attitudes regarding homeland security systems. Psychometric rating data were obtained from 182 respondents on psychological attributes associated with 12 distinct types of homeland security systems. An inverse relationship was observed for the overall rating attributes of acceptability and risk of civil liberties infringement. Principal components analysis yielded a two factor solution, with the rating scale loading pattern suggesting factors of Perceived Effectiveness and Perceived Intrusiveness. These factors also showed an inverse relationship.more » The 12 different homeland security systems showed significantly different scores on the rating scales and PCA factors, which were used to rank the systems in terms of overall acceptability. Difference scores for the rating scales and PCA factors were used to compute a single acceptability value reflecting the relative weight of risks and benefits. Of the 12 systems studied, airport screening, canine detectors and radiation monitoring at borders were found to be relatively acceptable, i.e., the perceived benefits for homeland security outweighed the perceived risks to civil liberties. Students rated several systems as more effective than professionals, but the overall pattern of results for both types of subjects was similar. The data suggest that risk perception research and the psychometric paradigm are useful approaches for quantifying attitudes regarding homeland security systems and policies, and can be used to anticipate potentially significant public acceptance issues.« less

Growth characteristics of a plane crack subjected to three-dimensional loading. [based on stress intensity factors

NASA Technical Reports Server (NTRS)

Hartranft, R. J.; Sih, G. C.

1973-01-01

The closed form expressions for the stress intensity factors due to concentrated forces applied to the surfaces of a half plane crack in an infinite body are used to generate solutions for distributed loads in this geometry. The stress intensity factors for uniformly distributed loads applied over a rectangular portion of the crack surface are given in closed form. An example of non-uniformly distributed loads which can be treated numerically is also included. In particular, combinations of normal and shear stresses on the crack which simulate the case of loading at an angle to the crack front are considered. The resulting stress intensity factors are combined with the strain energy density fracture criterion for the purpose of predicting the most likely direction of crack propagation. The critical value of the energy density factor can then be used for determining the allowable load on a specimen with a crack front not perpendicular to the tensile axis.

Forefoot strikers exhibit lower running-induced knee loading than rearfoot strikers.

PubMed

Kulmala, Juha-Pekka; Avela, Janne; Pasanen, Kati; Parkkari, Jari

2013-12-01

Knee pain and Achilles tendinopathies are the most common complaints among runners. The differences in the running mechanics may play an important role in the pathogenesis of lower limb overuse injuries. However, the effect of a runner's foot strike pattern on the ankle and especially on the knee loading is poorly understood. The purpose of this study was to examine whether runners using a forefoot strike pattern exhibit a different lower limb loading profile than runners who use rearfoot strike pattern. Nineteen female athletes with a natural forefoot strike (FFS) pattern and pair-matched women with rearfoot strike (RFS) pattern (n = 19) underwent 3-D running analysis at 4 m·s⁻¹. Joint angles and moments, patellofemoral contact force and stresses, and Achilles tendon forces were analyzed and compared between groups. FFS demonstrated lower patellofemoral contact force and stress compared with heel strikers (4.3 ± 1.2 vs 5.1 ± 1.1 body weight, P = 0.029, and 11.1 ± 2.9 vs 13.0 ± 2.8 MPa, P = 0.04). In addition, knee frontal plane moment was lower in the FFS compared with heel strikers (1.49 ± 0.51 vs 1.97 ± 0.66 N·m·kg⁻¹, P =0.015). At the ankle level, FFS showed higher plantarflexor moment (3.12 ± 0.40 vs 2.54 ± 0.37 N·m·kg⁻¹; P = 0.001) and Achilles tendon force (6.3 ± 0.8 vs 5.1 ± 1.3 body weight; P = 0.002) compared with RFS. To our knowledge, this is the first study that shows differences in patellofemoral loading and knee frontal plane moment between FFS and RFS. FFS exhibit both lower patellofemoral stress and knee frontal plane moment than RFS, which may reduce the risk of running-related knee injuries. On the other hand, parallel increase in ankle plantarflexor and Achilles tendon loading may increase risk for ankle and foot injuries.

A Study towards Building An Optimal Graph Theory Based Model For The Design of Tourism Website

NASA Astrophysics Data System (ADS)

Panigrahi, Goutam; Das, Anirban; Basu, Kajla

2010-10-01

Effective tourism website is a key to attract tourists from different parts of the world. Here we identify the factors of improving the effectiveness of website by considering it as a graph, where web pages including homepage are the nodes and hyperlinks are the edges between the nodes. In this model, the design constraints for building a tourism website are taken into consideration. Our objectives are to build a framework of an effective tourism website providing adequate level of information, service and also to enable the users to reach to the desired page by spending minimal loading time. In this paper an information hierarchy specifying the upper limit of outgoing link of a page has also been proposed. Following the hierarchy, the web developer can prepare an effective tourism website. Here loading time depends on page size and network traffic. We have assumed network traffic as uniform and the loading time is directly proportional with page size. This approach is done by quantifying the link structure of a tourism website. In this approach we also propose a page size distribution pattern of a tourism website.

14 CFR 23.341 - Gust loads factors.

Code of Federal Regulations, 2014 CFR

2014-01-01

... loads factors. (a) Each airplane must be designed to withstand loads on each lifting surface resulting...=airplane mass ratio; U de=Derived gust velocities referred to in § 23.333(c) (f.p.s.); ρ=Density of air... C NA per radian if the gust loads are applied to the wings and horizontal tail surfaces...

14 CFR 23.341 - Gust loads factors.

Code of Federal Regulations, 2012 CFR

2012-01-01

... loads factors. (a) Each airplane must be designed to withstand loads on each lifting surface resulting...=airplane mass ratio; U de=Derived gust velocities referred to in § 23.333(c) (f.p.s.); ρ=Density of air... C NA per radian if the gust loads are applied to the wings and horizontal tail surfaces...

14 CFR 23.341 - Gust loads factors.

Code of Federal Regulations, 2013 CFR

2013-01-01

... loads factors. (a) Each airplane must be designed to withstand loads on each lifting surface resulting...=airplane mass ratio; U de=Derived gust velocities referred to in § 23.333(c) (f.p.s.); ρ=Density of air... C NA per radian if the gust loads are applied to the wings and horizontal tail surfaces...

14 CFR 23.341 - Gust loads factors.

Code of Federal Regulations, 2011 CFR

2011-01-01

... loads factors. (a) Each airplane must be designed to withstand loads on each lifting surface resulting...=airplane mass ratio; U de=Derived gust velocities referred to in § 23.333(c) (f.p.s.); ρ=Density of air... C NA per radian if the gust loads are applied to the wings and horizontal tail surfaces...

Ternary nucleation as a mechanism for the production of diesel nanoparticles: experimental analysis of the volatile and hygroscopic properties of diesel exhaust using the volatilization and humidification tandem differential mobility analyzer.

PubMed

Meyer, N K; Ristovski, Z D

2007-11-01

The volatile and hygroscopic properties of diesel nanoparticles were simultaneously determined under a range of engine loads using the volatilization and humidification tandem differential mobility analyzer (VH-TDMA). Additionally, the VH-TDMA was used to measure changes in the hygroscopic behavior of the heterogeneously nucleated diesel nanoparticles as one or more semivolatile species were removed via thermal evaporation or decomposition. Particles produced at high loads exhibited high, dual-step volatility, while those particles produced at low loads were less volatile and exhibited continuous volatilization curves. The hygroscopic growth factor of the particles was shown to be load dependent with high-load particles exhibiting growth factors similar to that of ammonium sulfate. At 85% relative humidity, particles produced at moderate loads exhibited growth factors of approximately 1.1 while low-load particles were shown to be hydrophobic. Growth factors and volatilization temperatures measured for high-load particles clearly indicate that ternary nucleation is involved in particle formation.

Immune networks: multi-tasking capabilities at medium load

NASA Astrophysics Data System (ADS)

Agliari, E.; Annibale, A.; Barra, A.; Coolen, A. C. C.; Tantari, D.

2013-08-01

Associative network models featuring multi-tasking properties have been introduced recently and studied in the low-load regime, where the number P of simultaneously retrievable patterns scales with the number N of nodes as P ˜ log N. In addition to their relevance in artificial intelligence, these models are increasingly important in immunology, where stored patterns represent strategies to fight pathogens and nodes represent lymphocyte clones. They allow us to understand the crucial ability of the immune system to respond simultaneously to multiple distinct antigen invasions. Here we develop further the statistical mechanical analysis of such systems, by studying the medium-load regime, P ˜ Nδ with δ ∈ (0, 1]. We derive three main results. First, we reveal the nontrivial architecture of these networks: they exhibit a high degree of modularity and clustering, which is linked to their retrieval abilities. Second, by solving the model we demonstrate for δ < 1 the existence of large regions in the phase diagram where the network can retrieve all stored patterns simultaneously. Finally, in the high-load regime δ = 1 we find that the system behaves as a spin-glass, suggesting that finite-connectivity frameworks are required to achieve effective retrieval.

Compensated Box-Jenkins transfer function for short term load forecast

DOE Office of Scientific and Technical Information (OSTI.GOV)

Breipohl, A.; Yu, Z.; Lee, F.N.

In the past years, the Box-Jenkins ARIMA method and the Box-Jenkins transfer function method (BJTF) have been among the most commonly used methods for short term electrical load forecasting. But when there exists a sudden change in the temperature, both methods tend to exhibit larger errors in the forecast. This paper demonstrates that the load forecasting errors resulting from either the BJ ARIMA model or the BJTF model are not simply white noise, but rather well-patterned noise, and the patterns in the noise can be used to improve the forecasts. Thus a compensated Box-Jenkins transfer method (CBJTF) is proposed tomore » improve the accuracy of the load prediction. Some case studies have been made which result in about a 14-33% reduction of the root mean square (RMS) errors of the forecasts, depending on the compensation time period as well as the compensation method used.« less

In situ forces and length patterns of the fibular collateral ligament under controlled loading: an in vitro biomechanical study using a robotic system.

PubMed

Liu, Ping; Wang, Jianquan; Xu, Yan; Ao, Yingfang

2015-04-01

The aim of this study was to determine the in situ forces and length patterns of the fibular collateral ligament (FCL) and kinematics of the knee under various loading conditions. Six fresh-frozen cadaveric knees were used (mean age 46 ± 14.4 years; range 20-58). In situ forces and length patterns of FCL and kinematics of the knee were determined under the following loading conditions using a robotic/universal force-moment sensor testing system: no rotation, varus (10 Nm), external rotation (5 Nm), and internal rotation (5 Nm) at 0°, 15°, 30°, 60º, 90°, and 120° of flexion, respectively. Under no rotation loading, the distances between the centres of the FCL attachments decreased as the knee flexed. Under varus loading, the force in FCL peaked at 15° of flexion and decreased with further knee flexion, while distances remained nearly constant and the varus rotation increased with knee flexion. Using external rotation, the force in the FCL also peaked at 15° flexion and decreased with further knee flexion, the distances decreased with flexion, and external rotation increased with knee flexion. Using internal rotation load, the force in the FCL was relatively small across all knee flexion angles, and the distances decreased with flexion; the amount of internal rotation was fairly constant. FCL has a primary role in preventing varus and external rotation at 15° of flexion. The FCL does not perform isometrically following knee flexion during neutral rotation, and tibia rotation has significant effects on the kinematics of the FCL. Varus and external rotation laxity increased following knee flexion. By providing more realistic data about the function and length patterns of the FCL and the kinematics of the intact knee, improved reconstruction and rehabilitation protocols can be developed.

Physical properties, chemical composition, and cloud forming potential of particulate emissions from a marine diesel engine at various load conditions.

PubMed

Petzold, A; Weingartner, E; Hasselbach, J; Lauer, P; Kurok, C; Fleischer, F

2010-05-15

Particulate matter (PM) emissions from one serial 4-stroke medium-speed marine diesel engine were measured for load conditions from 10% to 110% in test rig studies using heavy fuel oil (HFO). Testing the engine across its entire load range permitted the scaling of exhaust PM properties with load. Emission factors for particle number, particle mass, and chemical compounds were determined. The potential of particles to form cloud droplets (cloud condensation nuclei, CCN) was calculated from chemical composition and particle size. Number emission factors are (3.43 +/- 1.26) x 10(16) (kg fuel)(-1) at 85-110% load and (1.06 +/- 0.10) x 10(16) (kg fuel)(-1) at 10% load. CCN emission factors of 1-6 x 10(14) (kg fuel)(-1) are at the lower bound of data reported in the literature. From combined thermal and optical methods, black carbon (BC) emission factors of 40-60 mg/(kg fuel) were determined for 85-100% load and 370 mg/(kg fuel) for 10% load. The engine load dependence of the conversion efficiency for fuel sulfur into sulfate of (1.08 +/- 0.15)% at engine idle to (3.85 +/- 0.41)% at cruise may serve as input to global emission calculations for various load conditions.

Method and apparatus of prefetching streams of varying prefetch depth

DOEpatents

Gara, Alan [Mount Kisco, NY; Ohmacht, Martin [Yorktown Heights, NY; Salapura, Valentina [Chappaqua, NY; Sugavanam, Krishnan [Mahopac, NY; Hoenicke, Dirk [Seebruck-Seeon, DE

2012-01-24

Method and apparatus of prefetching streams of varying prefetch depth dynamically changes the depth of prefetching so that the number of multiple streams as well as the hit rate of a single stream are optimized. The method and apparatus in one aspect monitor a plurality of load requests from a processing unit for data in a prefetch buffer, determine an access pattern associated with the plurality of load requests and adjust a prefetch depth according to the access pattern.

Polysilicon planarization and plug recess etching in a decoupled plasma source chamber using two endpoint techniques

NASA Astrophysics Data System (ADS)

Kaplita, George A.; Schmitz, Stefan; Ranade, Rajiv; Mathad, Gangadhara S.

1999-09-01

The planarization and recessing of polysilicon to form a plug are processes of increasing importance in silicon IC fabrication. While this technology has been developed and applied to DRAM technology using Trench Storage Capacitors, the need for such processes in other IC applications (i.e. polysilicon studs) has increased. Both planarization and recess processes usually have stringent requirements on etch rate, recess uniformity, and selectivity to underlying films. Additionally, both processes generally must be isotropic, yet must not expand any seams that might be present in the polysilicon fill. These processes should also be insensitive to changes in exposed silicon area (pattern factor) on the wafer. A SF6 plasma process in a polysilicon DPS (Decoupled Plasma Source) reactor has demonstrated the capability of achieving the above process requirements for both planarization and recess etch. The SF6 process in the decoupled plasma source reactor exhibited less sensitivity to pattern factor than in other types of reactors. Control of these planarization and recess processes requires two endpoint systems to work sequentially in the same recipe: one for monitoring the endpoint when blanket polysilicon (100% Si loading) is being planarized and one for monitoring the recess depth while the plug is being recessed (less than 10% Si loading). The planarization process employs an optical emission endpoint system (OES). An interferometric endpoint system (IEP), capable of monitoring lateral interference, is used for determining the recess depth. The ability of using either or both systems is required to make these plug processes manufacturable. Measuring the recess depth resulting from the recess process can be difficult, costly and time- consuming. An Atomic Force Microscope (AFM) can greatly alleviate these problems and can serve as a critical tool in the development of recess processes.

Advanced overlay analysis through design based metrology

NASA Astrophysics Data System (ADS)

Ji, Sunkeun; Yoo, Gyun; Jo, Gyoyeon; Kang, Hyunwoo; Park, Minwoo; Kim, Jungchan; Park, Chanha; Yang, Hyunjo; Yim, Donggyu; Maruyama, Kotaro; Park, Byungjun; Yamamoto, Masahiro

2015-03-01

As design rule shrink, overlay has been critical factor for semiconductor manufacturing. However, the overlay error which is determined by a conventional measurement with an overlay mark based on IBO and DBO often does not represent the physical placement error in the cell area. The mismatch may arise from the size or pitch difference between the overlay mark and the cell pattern. Pattern distortion caused by etching or CMP also can be a source of the mismatch. In 2014, we have demonstrated that method of overlay measurement in the cell area by using DBM (Design Based Metrology) tool has more accurate overlay value than conventional method by using an overlay mark. We have verified the reproducibility by measuring repeatable patterns in the cell area, and also demonstrated the reliability by comparing with CD-SEM data. We have focused overlay mismatching between overlay mark and cell area until now, further more we have concerned with the cell area having different pattern density and etch loading. There appears a phenomenon which has different overlay values on the cells with diverse patterning environment. In this paper, the overlay error was investigated from cell edge to center. For this experiment, we have verified several critical layers in DRAM by using improved(Better resolution and speed) DBM tool, NGR3520.

Patterns of morning and evening fatigue among adults with HIV/AIDS.

PubMed

Lerdal, Anners; Gay, Caryl L; Aouizerat, Bradley E; Portillo, Carmen J; Lee, Kathryn A

2011-08-01

Describe patterns of morning and evening fatigue in adults with HIV and examine their relationship to demographic and clinical factors and other symptoms. Most studies of HIV-related fatigue assess average levels of fatigue and do not address its diurnal fluctuations. Patterns of fatigue over the course of the day may have important implications for assessment and treatment. A cross-sectional, correlational design was used with six repeated measures over 72 hours. A convenience sample of 318 HIV-infected adults was recruited in San Francisco. Socio-demographic, clinical and symptom data were collected with questionnaires. CD4+ T-cell count and viral load were obtained from medical records. Participants completed a four-item version of the Lee Fatigue Scale each morning and evening for three consecutive days. Participants were grouped based on their diurnal pattern of fatigue (high evening only, high morning only, high morning and evening and low morning and evening). Group comparisons and logistic regression were used to determine the unique predictors of each fatigue pattern. The high evening fatigue pattern was associated with anxiety and the high morning pattern was associated with anxiety and depression. The morning fatigue pattern showed very little fluctuation between morning and evening, the evening pattern showed the largest fluctuation. The high morning and evening pattern was associated with anxiety, depression and sleep disturbance and this group reported the most fatigue-related distress and interference in functioning. These results provide initial evidence for the importance of assessing the patient's daily pattern of fatigue fluctuation, as different patterns were associated with different symptom experiences and perhaps different aetiologies. Different fatigue patterns may benefit from tailored intervention strategies. Management of depressive symptoms could be tested in patients who experience high levels of morning fatigue. © 2011 Blackwell Publishing Ltd.

14 CFR 27.473 - Ground loading conditions and assumptions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... through the center of gravity throughout the landing impact. This lift may not exceed two-thirds of the... rotorcraft must be designed for a limit load factor of not less than the limit inertia load factor...

14 CFR 27.473 - Ground loading conditions and assumptions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... through the center of gravity throughout the landing impact. This lift may not exceed two-thirds of the... rotorcraft must be designed for a limit load factor of not less than the limit inertia load factor...

14 CFR 27.473 - Ground loading conditions and assumptions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... through the center of gravity throughout the landing impact. This lift may not exceed two-thirds of the... rotorcraft must be designed for a limit load factor of not less than the limit inertia load factor...

Improved LRFD/LRFR specifications for permit and fatigue load truck.

DOT National Transportation Integrated Search

2011-01-01

Bridge design and evaluation are moving toward the American Association of State Highway and Transportation : Officials (AASHTO) load and resistance factor design/load and resistance factor rating (LRFD/LRFR) : specifications using calibrated truck l...

Healthy eating opinion survey for individuals at risk for cardiovascular disease.

PubMed

Mark, Amy E; Riley, Dana L; McDonnell, Lisa A; Pipe, Andrew L; Reid, Robert D

2014-08-01

To develop and evaluate the validity and reliability of a questionnaire to measure intentions and beliefs about healthy eating in individuals at risk for coronary heart disease. The Healthy Eating Opinion Survey was developed using the theory of planned behavior. An open-ended elicitation questionnaire was administered to 21 participants, and a 46-item questionnaire was developed for further testing. Test-retest reliability of each question on the survey was assessed by calculating the correlation coefficients between the responses over a 2- week period in 17 participants. Internal consistency was assessed using Cronbach's alpha, and factor analysis was used to assess the construct validity of the questionnaire in a sample of 388 participants. The responses to the elicitation questions were used to develop behavioral beliefs, normative beliefs, and control beliefs questions for the final questionnaire. Test-retest reliability ranged from 0.22-0.90, with the majority (89%) of correlations being moderate to strong. Internal consistency was good, with Cronbach's alpha ranging from 0.74-0.92. All intentions questions loaded onto a single factor; attitude questions loaded onto two factors; subjective norm questions loaded onto two factors; perceived behavioral control questions loaded onto one factor; behavioral beliefs questions loaded onto one factor; normative beliefs questions loaded onto one factor; and control beliefs questions loaded onto one factor. The questionnaire was found to be a reliable, valid questionnaire to assess beliefs and intentions toward eating a healthy diet in individuals at risk for coronary heart disease.

Axial displacement of external and internal implant-abutment connection evaluated by linear mixed model analysis.

PubMed

Seol, Hyon-Woo; Heo, Seong-Joo; Koak, Jai-Young; Kim, Seong-Kyun; Kim, Shin-Koo

2015-01-01

To analyze the axial displacement of external and internal implant-abutment connection after cyclic loading. Three groups of external abutments (Ext group), an internal tapered one-piece-type abutment (Int-1 group), and an internal tapered two-piece-type abutment (Int-2 group) were prepared. Cyclic loading was applied to implant-abutment assemblies at 150 N with a frequency of 3 Hz. The amount of axial displacement, the Periotest values (PTVs), and the removal torque values(RTVs) were measured. Both a repeated measures analysis of variance and pattern analysis based on the linear mixed model were used for statistical analysis. Scanning electron microscopy (SEM) was used to evaluate the surface of the implant-abutment connection. The mean axial displacements after 1,000,000 cycles were 0.6 μm in the Ext group, 3.7 μm in the Int-1 group, and 9.0 μm in the Int-2 group. Pattern analysis revealed a breakpoint at 171 cycles. The Ext group showed no declining pattern, and the Int-1 group showed no declining pattern after the breakpoint (171 cycles). However, the Int-2 group experienced continuous axial displacement. After cyclic loading, the PTV decreased in the Int-2 group, and the RTV decreased in all groups. SEM imaging revealed surface wear in all groups. Axial displacement and surface wear occurred in all groups. The PTVs remained stable, but the RTVs decreased after cyclic loading. Based on linear mixed model analysis, the Ext and Int-1 groups' axial displacements plateaued after little cyclic loading. The Int-2 group's rate of axial displacement slowed after 100,000 cycles.

Internalizing and externalizing problems in adolescence: general and dimension-specific effects of familial loadings and preadolescent temperament traits.

PubMed

Ormel, J; Oldehinkel, A J; Ferdinand, R F; Hartman, C A; De Winter, A F; Veenstra, R; Vollebergh, W; Minderaa, R B; Buitelaar, J K; Verhulst, F C

2005-12-01

We investigated the links between familial loading, preadolescent temperament, and internalizing and externalizing problems in adolescence, hereby distinguishing effects on maladjustment in general versus dimension-specific effects on either internalizing or externalizing problems. In a population-based sample of 2230 preadolescents (10-11 years) familial loading (parental lifetime psychopathology) and offspring temperament were assessed at baseline by parent report, and offspring psychopathology at 2.5-years follow-up by self-report, teacher report and parent report. We used purified measures of temperament and psychopathology and partialled out shared variance between internalizing and externalizing problems. Familial loading of internalizing psychopathology predicted offspring internalizing but not externalizing problems, whereas familial loading of externalizing psychopathology predicted offspring externalizing but not internalizing problems. Both familial loadings were associated with Frustration, low Effortful Control, and Fear. Frustration acted as a general risk factor predicting severity of maladjustment; low Effortful Control and Fear acted as dimension-specific risk factors that predicted a particular type of psychopathology; whereas Shyness, High-Intensity Pleasure, and Affiliation acted as direction markers that steered the conditional probability of internalizing versus externalizing problems, in the event of maladjustment. Temperament traits mediated one-third of the association between familial loading and psychopathology. Findings were robust across different composite measures of psychopathology, and applied to girls as well as boys. With regard to familial loading and temperament, it is important to distinguish general risk factors (Frustration) from dimension-specific risk factors (familial loadings, Effortful Control, Fear), and direction markers that act as pathoplastic factors (Shyness, High-Intensity Pleasure, Affiliation) from both types of risk factors. About one-third of familial loading effects on psychopathology in early adolescence are mediated by temperament.

14 CFR 29.473 - Ground loading conditions and assumptions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... through the center of gravity throughout the landing impact. This lift may not exceed two-thirds of the... rotorcraft must be designed for a limit load factor of not less than the limit inertia load factor... factor of safety prescribed in § 29.303 need not be used. [Amdt. 29-3, 33 FR 966, Jan. 26, 1968] ...

14 CFR 29.473 - Ground loading conditions and assumptions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... through the center of gravity throughout the landing impact. This lift may not exceed two-thirds of the... rotorcraft must be designed for a limit load factor of not less than the limit inertia load factor... factor of safety prescribed in § 29.303 need not be used. [Amdt. 29-3, 33 FR 966, Jan. 26, 1968] ...

14 CFR 29.473 - Ground loading conditions and assumptions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... through the center of gravity throughout the landing impact. This lift may not exceed two-thirds of the... rotorcraft must be designed for a limit load factor of not less than the limit inertia load factor... factor of safety prescribed in § 29.303 need not be used. [Amdt. 29-3, 33 FR 966, Jan. 26, 1968] ...

14 CFR 23.725 - Limit drop tests.

Code of Federal Regulations, 2011 CFR

2011-01-01

... assumed wing lift to the airplane weight, but not more than 0.667. (c) The limit inertia load factor must... test. (e) The limit inertia load factor must be determined from the drop test in paragraph (b) of this... paragraph (e) may not be more than the limit inertia load factor used in the landing conditions in § 23.473...

14 CFR 23.725 - Limit drop tests.

Code of Federal Regulations, 2013 CFR

2013-01-01

... assumed wing lift to the airplane weight, but not more than 0.667. (c) The limit inertia load factor must... test. (e) The limit inertia load factor must be determined from the drop test in paragraph (b) of this... paragraph (e) may not be more than the limit inertia load factor used in the landing conditions in § 23.473...

14 CFR 23.725 - Limit drop tests.

Code of Federal Regulations, 2012 CFR

2012-01-01

... assumed wing lift to the airplane weight, but not more than 0.667. (c) The limit inertia load factor must... test. (e) The limit inertia load factor must be determined from the drop test in paragraph (b) of this... paragraph (e) may not be more than the limit inertia load factor used in the landing conditions in § 23.473...

14 CFR 23.725 - Limit drop tests.

Code of Federal Regulations, 2014 CFR

2014-01-01

... assumed wing lift to the airplane weight, but not more than 0.667. (c) The limit inertia load factor must... test. (e) The limit inertia load factor must be determined from the drop test in paragraph (b) of this... paragraph (e) may not be more than the limit inertia load factor used in the landing conditions in § 23.473...

In vivo contact kinematics and contact forces of the knee after total knee arthroplasty during dynamic weight-bearing activities.

PubMed

Varadarajan, Kartik M; Moynihan, Angela L; D'Lima, Darryl; Colwell, Clifford W; Li, Guoan

2008-07-19

Analysis of polyethylene component wear and implant loosening in total knee arthroplasty (TKA) requires precise knowledge of in vivo articular motion and loading conditions. This study presents a simultaneous in vivo measurement of tibiofemoral articular contact forces and contact kinematics in three TKA patients. These measurements were accomplished via a dual fluoroscopic imaging system and instrumented tibial implants, during dynamic single leg lunge and chair rising-sitting. The measured forces and contact locations were also used to determine mediolateral distribution of axial contact forces. Contact kinematics data showed a medial pivot during flexion of the knee, for all patients in the study. Average axial forces were higher for lunge compared to chair rising-sitting (224% vs. 187% body weight). In this study, we measured peak anteroposterior and mediolateral forces averaging 13.3% BW during lunge and 18.5% BW during chair rising-sitting. Mediolateral distributions of axial contact force were both patient and activity specific. All patients showed equitable medial-lateral loading during lunge but greater loads at the lateral compartment during chair rising-sitting. The results of this study may enable more accurate reproduction of in vivo loads and articular motion patterns in wear simulators and finite element models. This in turn may help advance our understanding of factors limiting longevity of TKA implants, such as aseptic loosening and polyethylene component wear, and enable improved TKA designs.

Sea level side loads in high-area-ratio rocket engines

NASA Technical Reports Server (NTRS)

Nave, L. H.; Coffey, G. A.

1973-01-01

An empirical separation and side load model to obtain applied aerodynamic loads has been developed based on data obtained from full-scale J-2S (265K-pound-thrust engine with an area ratio of 40:1) engine and model testing. Experimental data include visual observations of the separation patterns that show the dynamic nature of the separation phenomenon. Comparisons between measured and applied side loads are made. Correlations relating the separation location to the applied side loads and the methods used to determine the separation location are given.

Low-damage direct patterning of silicon oxide mask by mechanical processing

PubMed Central

2014-01-01

To realize the nanofabrication of silicon surfaces using atomic force microscopy (AFM), we investigated the etching of mechanically processed oxide masks using potassium hydroxide (KOH) solution. The dependence of the KOH solution etching rate on the load and scanning density of the mechanical pre-processing was evaluated. Particular load ranges were found to increase the etching rate, and the silicon etching rate also increased with removal of the natural oxide layer by diamond tip sliding. In contrast, the local oxide pattern formed (due to mechanochemical reaction of the silicon) by tip sliding at higher load was found to have higher etching resistance than that of unprocessed areas. The profile changes caused by the etching of the mechanically pre-processed areas with the KOH solution were also investigated. First, protuberances were processed by diamond tip sliding at lower and higher stresses than that of the shearing strength. Mechanical processing at low load and scanning density to remove the natural oxide layer was then performed. The KOH solution selectively etched the low load and scanning density processed area first and then etched the unprocessed silicon area. In contrast, the protuberances pre-processed at higher load were hardly etched. The etching resistance of plastic deformed layers was decreased, and their etching rate was increased because of surface damage induced by the pre-processing. These results show that etching depth can be controlled by controlling the etching time through natural oxide layer removal and mechanochemical oxide layer formation. These oxide layer removal and formation processes can be exploited to realize low-damage mask patterns. PMID:24948891

Reasons, perceived efficacy, and factors associated with complementary and alternative medicine use among Malaysian patients with HIV/AIDS.

PubMed

Hasan, Syed Shahzad; See, Choon Keong; Choong, Christopher Lee Kwok; Ahmed, Syed Imran; Ahmadi, Keivan; Anwar, Mudassir

2010-11-01

The primary objective of this study was to evaluate the pattern of use, reasons for use, and perceived effect of complementary and alternative medicine (CAM), accompanied by identification and comparison of the factors that are potentially associated with CAM use. This cross-sectional study was carried out in 325 randomly sampled patients with human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS), at HIV/AIDS referral clinics in the Hospital Sungai Buloh, Malaysia. Simple random sampling was used, where randomization was done using patients' medical record numbers. Semistructured face-to-face interviews were conducted using 38 questions pertaining to type, pattern, perceived efficacy, adverse effects, and influential factors associated with CAM use. In addition, CD4 count and viral load readings were recorded. Of 325 randomly sampled patients with HIV/AIDS, 254 of them were using some forms of CAM, resulting in a utilization rate of 78.2%. Vitamins and supplements (52.6%), herbal products (33.8%), and massage (16.6%) were the top three most frequently used CAM modalities. Sociodemographic factors including education level (p = 0.021, r(s) = 0.148), monthly income (p = 0.001, r(s) = 0.260), and family history of CAM use (p = 0.001, r(s) = 0.231) were significantly associated and positively correlated with CAM use. However, the majority of these patients (68%) did not disclose CAM use to health care professionals. About half of those who rated their health as good or very good perceived it as a result of CAM use. This study confirmed the range of 30%-100% CAM use among individuals infected with HIV/AIDS. Although, on the one hand some types of CAM reduced viral load and enhanced the immune system, on the other hand some forms of CAM produced a detrimental effect on the virological suppression, opening this platform to more research and investigation in order to optimize the use of CAM among patients with HIV/AIDS.

Parietal-Occipital Interactions Underlying Control- and Representation-Related Processes in Working Memory for Nonspatial Visual Features.

PubMed

Gosseries, Olivia; Yu, Qing; LaRocque, Joshua J; Starrett, Michael J; Rose, Nathan S; Cowan, Nelson; Postle, Bradley R

2018-05-02

Although the manipulation of load is popular in visual working memory research, many studies confound general attentional demands with context binding by drawing memoranda from the same stimulus category. In this fMRI study of human observers (both sexes), we created high- versus low-binding conditions, while holding load constant, by comparing trials requiring memory for the direction of motion of one random dot kinematogram (RDK; 1M trials) versus for three RDKs (3M), or versus one RDK and two color patches (1M2C). Memory precision was highest for 1M trials and comparable for 3M and 1M2C trials. And although delay-period activity in occipital cortex did not differ between the three conditions, returning to baseline for all three, multivariate pattern analysis decoding of a remembered RDK from occipital cortex was also highest for 1M trials and comparable for 3M and 1M2C trials. Delay-period activity in intraparietal sulcus (IPS), although elevated for all three conditions, displayed more sensitivity to demands on context binding than to load per se. The 1M-to-3M increase in IPS signal predicted the 1M-to-3M declines in both behavioral and neural estimates of working memory precision. These effects strengthened along a caudal-to-rostral gradient, from IPS0 to IPS5. Context binding-independent load sensitivity was observed when analyses were lateralized and extended into PFC, with trend-level effects evident in left IPS and strong effects in left lateral PFC. These findings illustrate how visual working memory capacity limitations arise from multiple factors that each recruit dissociable brain systems. SIGNIFICANCE STATEMENT Visual working memory capacity predicts performance on a wide array of cognitive and real-world outcomes. At least two theoretically distinct factors are proposed to influence visual working memory capacity limitations: an amodal attentional resource that must be shared across remembered items; and the demands on context binding. We unconfounded these two factors by varying load with items drawn from the same stimulus category ("high demands on context binding") versus items drawn from different stimulus categories ("low demands on context binding"). The results provide evidence for the dissociability, and the neural bases, of these two theorized factors, and they specify that the functions of intraparietal sulcus may relate more strongly to the control of representations than to the general allocation of attention. Copyright © 2018 the authors 0270-6474/18/384357-10$15.00/0.

14 CFR 23.301 - Loads.

Code of Federal Regulations, 2010 CFR

2010-01-01

... load would significantly change the distribution of external or internal loads, this redistribution...) and ultimate loads (limit loads multiplied by prescribed factors of safety). Unless otherwise provided...

An equilibrium-point model of electromyographic patterns during single-joint movements based on experimentally reconstructed control signals.

PubMed

Latash, M L; Goodman, S R

1994-01-01

The purpose of this work has been to develop a model of electromyographic (EMG) patterns during single-joint movements based on a version of the equilibrium-point hypothesis, a method for experimental reconstruction of the joint compliant characteristics, the dual-strategy hypothesis, and a kinematic model of movement trajectory. EMG patterns are considered emergent properties of hypothetical control patterns that are equally affected by the control signals and peripheral feedback reflecting actual movement trajectory. A computer model generated the EMG patterns based on simulated movement kinematics and hypothetical control signals derived from the reconstructed joint compliant characteristics. The model predictions have been compared to published recordings of movement kinematics and EMG patterns in a variety of movement conditions, including movements over different distances, at different speeds, against different-known inertial loads, and in conditions of possible unexpected decrease in the inertial load. Changes in task parameters within the model led to simulated EMG patterns qualitatively similar to the experimentally recorded EMG patterns. The model's predictive power compares it favourably to the existing models of the EMG patterns. Copyright © 1994. Published by Elsevier Ltd.

Wind loads on flat plate photovoltaic array fields (nonsteady winds)

NASA Technical Reports Server (NTRS)

Miller, R. D.; Zimmerman, D. K.

1981-01-01

Techniques to predict the dynamic response and the structural dynamic loads of flat plate photovoltaic arrays due to wind turbulence were analyzed. Guidelines for use in predicting the turbulent portion of the wind loading on future similar arrays are presented. The dynamic response and the loads dynamic magnification factor of the two array configurations are similar. The magnification factors at a mid chord and outer chord location on the array illustrated and at four points on the chord are shown. The wind tunnel test experimental rms pressure coefficient on which magnification factors are based is shown. It is found that the largest response and dynamic magnification factor occur at a mid chord location on an array and near the trailing edge. A technique employing these magnification factors and the wind tunnel test rms fluctuating pressure coefficients to calculate design pressure loads due to wind turbulence is presented.

A novel ex vivo model of compressive immature rib fractures at pathophysiological rates of loading.

PubMed

Beadle, Nicola; Burnett, Timothy L; Hoyland, Judith A; Sherratt, Michael J; Freemont, Anthony J

2015-11-01

Compressive rib fractures are considered to be indicative of non-accidental injury (NAI) in infants, which is a significant and growing issue worldwide. The diagnosis of NAI is often disputed in a legal setting, and as a consequence there is a need to model such injuries ex vivo in order to characterise the forces required to produce non-accidental rib fractures. However, current models are limited by type of sample, loading method and rate of loading. Here, we aimed to: i) develop a loading system for inducing compressive fractures in whole immature ribs that is more representative of the physiological conditions and mechanism of injury employed in NAI and ii) assess the influence of loading rate and rib geometry on the mechanical performance of the tissue. Porcine ribs (5-6 weeks of age) from 12 animals (n=8 ribs/animal) were subjected to axial compressive load directed through the anterior-posterior rib axis at loading rates of 1, 30, 60 or 90 mm/s. Key mechanical parameters (including peak load, load and percentage deformation to failure and effective stiffness) were quantified from the load-displacement curves. Measurements of the rib length, thickness at midpoint, distance between anterior and posterior extremities, rib curvature and fracture location were determined from radiographs. This loading method typically produced incomplete fractures around the midpoint of the ribs, with 87% failing in this manner; higher loads and less deformation were required for ribs to completely fracture through both cortices. Loading rate, within the range of 1-90 mm/s, did not significantly affect any key mechanical parameters of the ribs. Load-displacement curves displaying characteristic and quantifiable features were produced for 90% of the ribs tested, and multiple regression analyses indicate that, in addition to the geometrical variables, there are other factors such as the micro- and nano-structure that influence the measured mechanical data. A reproducible method of inducing fractures in a consistent location in immature porcine ribs has been successfully developed. Fracture appearance may be indicative of the amount of load and deformation that produced the fracture, which is an important finding for NAI, where knowledge of the aetiology of fractures is vital. Characteristic rib behaviour independent of loading rate and, to an extent, rib geometry has been demonstrated, allowing further investigation into how the complex micro- and nano-structure of immature ribs influences the mechanical performance under compressive load. This research will ultimately enable improved characterisation of the loading pattern involved in non-accidental rib fractures. Copyright © 2015 Elsevier Ltd. All rights reserved.

Performance of a novel two-phase continuously fed leach bed reactor for demand-based biogas production from maize silage.

PubMed

Linke, Bernd; Rodríguez-Abalde, Ángela; Jost, Carsten; Krieg, Andreas

2015-02-01

This study investigated the potential of producing biogas on demand from maize silage using a novel two-phase continuously fed leach bed reactor (LBR) which is connected to an anaerobic filter (AF). Six different feeding patterns, each for 1week, were studied at a weekly average of a volatile solids (VS) loading rate of 4.5 g L(-1) d(-1) and a temperature of 38°C. Methane production from the LBR and AF responded directly proportional to the VS load from the different daily feeding and resulted in an increase up to 50-60% per day, compared to constant feeding each day. The feeding patterns had no impact on VS methane yield which corresponded on average to 330 L kg(-1). In spite of some daily shock loadings, carried out during the different feeding patterns study, the reactor performance was not affected. A robust and reliable biogas production from stalky biomass was demonstrated. Copyright © 2014 Elsevier Ltd. All rights reserved.

Lower Extremity Biomechanics and Self-Reported Foot-Strike Patterns Among Runners in Traditional and Minimalist Shoes.

PubMed

Goss, Donald L; Lewek, Michael; Yu, Bing; Ware, William B; Teyhen, Deydre S; Gross, Michael T

2015-06-01

The injury incidence rate among runners is approximately 50%. Some individuals have advocated using an anterior-foot-strike pattern to reduce ground reaction forces and injury rates that they attribute to a rear-foot-strike pattern. The proportion of minimalist shoe wearers who adopt an anterior-foot-strike pattern remains unclear. To evaluate the accuracy of self-reported foot-strike patterns, compare negative ankle- and knee-joint angular work among runners using different foot-strike patterns and wearing traditional or minimalist shoes, and describe average vertical-loading rates. Descriptive laboratory study. Research laboratory. A total of 60 healthy volunteers (37 men, 23 women; age = 34.9 ± 8.9 years, height = 1.74 ± 0.08 m, mass = 70.9 ± 13.4 kg) with more than 6 months of experience wearing traditional or minimalist shoes were instructed to classify their foot-strike patterns. Participants ran in their preferred shoes on an instrumented treadmill with 3-dimensional motion capture. Self-reported foot-strike patterns were compared with 2-dimensional video assessments. Runners were classified into 3 groups based on video assessment: traditional-shoe rear-foot strikers (TSR; n = 22), minimalist-shoe anterior-foot strikers (MSA; n = 21), and minimalist-shoe rear-foot strikers (MSR; n = 17). Ankle and knee negative angular work and average vertical-loading rates during stance phase were compared among groups. Only 41 (68.3%) runners reported foot-strike patterns that agreed with the video assessment (κ = 0.42, P < .001). The TSR runners demonstrated greater ankle-dorsiflexion and knee-extension negative work than MSA and MSR runners (P < .05). The MSA (P < .001) and MSR (P = .01) runners demonstrated greater ankle plantar-flexion negative work than TSR runners. The MSR runners demonstrated a greater average vertical-loading rate than MSA and TSR runners (P < .001). Runners often cannot report their foot-strike patterns accurately and may not automatically adopt an anterior-foot-strike pattern after transitioning to minimalist running shoes.

Load to Failure and Stiffness

PubMed Central

Esquivel, Amanda O.; Duncan, Douglas D.; Dobrasevic, Nikola; Marsh, Stephanie M.; Lemos, Stephen E.

2015-01-01

Background: Rotator cuff tendinopathy is a frequent cause of shoulder pain that can lead to decreased strength and range of motion. Failures after using the single-row technique of rotator cuff repair have led to the development of the double-row technique, which is said to allow for more anatomical restoration of the footprint. Purpose: To compare 5 different types of suture patterns while maintaining equality in number of anchors. The hypothesis was that the Mason-Allen–crossed cruciform transosseous-equivalent technique is superior to other suture configurations while maintaining equality in suture limbs and anchors. Study Design: Controlled laboratory study. Methods: A total of 25 fresh-frozen cadaveric shoulders were randomized into 5 suture configuration groups: single-row repair with simple stitch technique; single-row repair with modified Mason-Allen technique; double-row Mason-Allen technique; double-row cross-bridge technique; and double-row suture bridge technique. Load and displacement were recorded at 100 Hz until failure. Stiffness and bone mineral density were also measured. Results: There was no significant difference in peak load at failure, stiffness, maximum displacement at failure, or mean bone mineral density among the 5 suture configuration groups (P < .05). Conclusion: According to study results, when choosing a repair technique, other factors such as number of sutures in the repair should be considered to judge the strength of the repair. Clinical Relevance: Previous in vitro studies have shown the double-row rotator cuff repair to be superior to the single-row repair; however, clinical research does not necessarily support this. This study found no difference when comparing 5 different repair methods, supporting research that suggests the number of sutures and not the pattern can affect biomechanical properties. PMID:26665053

Radiotherapy for brain metastases in southern Thailand: workload, treatment pattern and survival.

PubMed

Phungrassami, Temsak; Sriplung, Hutcha

2015-01-01

To study the patient load, treatment pattern, survival outcome and its predictors in patients with brain metastases treated by radiotherapy. Data for patients with brain metastases treated by radiotherapy between 2003 and 2007 were collected from medical records, the hospital information system database, and a population-based tumor registry database until death or at least 5 years after treatment and retrospectively reviewed. The number of treatments for brain metastases gradually increased from 48 in 2003 to 107 in 2007, with more than 70% from lung and breast cancers. The majority were treated with whole brain radiation of 30 Gy (3 Gy X 10 fractions) by cobalt-60 machine, using radiation alone. The overall median survival of the 418 patients was 3.9 months. Cohort analysis of relative survival after radiotherapy was as follows: 52% at 3 months, 18% at 1 year and 3% at 5 years in males; and 66% at 3 months, 26% at 1 year and 7% at 5 years in females. Multivariate analysis demonstrated that the patients treated with combined modalities had a better prognosis. Poor prognostic factors included primary cancer from the lung or gastrointestinal tract, emergency or urgent consultation, poor performance status (ECOG 3-4), and a hemoglobin level before treatment of less than 10 g/dl. This study identified an increasing trend of patient load with brain metastases. Possible over-treatment and under-treatment were demonstrated with a wide range of survival results. Practical prognostic scoring systems to assist in decision-making for optimal treatment of different patient groups is absolutely necessary; it is a key strategy for balancing good quality of care and patient load.

Shape-anchored porous polymer monoliths for integrated online solid-phase extraction-microchip electrophoresis-electrospray ionization mass spectrometry.

PubMed

Nordman, Nina; Barrios-Lopez, Brianda; Laurén, Susanna; Suvanto, Pia; Kotiaho, Tapio; Franssila, Sami; Kostiainen, Risto; Sikanen, Tiina

2015-02-01

We report a simple protocol for fabrication of shape-anchored porous polymer monoliths (PPMs) for on-chip SPE prior to online microchip electrophoresis (ME) separation and on-chip (ESI/MS). The chip design comprises a standard ME separation channel with simple cross injector and a fully integrated ESI emitter featuring coaxial sheath liquid channel. The monolith zone was prepared in situ at the injection cross by laser-initiated photopolymerization through the microchip cover layer. The use of high-power laser allowed not only maskless patterning of a precisely defined monolith zone, but also faster exposure time (here, 7 min) compared with flood exposure UV lamps. The size of the monolith pattern was defined by the diameter of the laser output (∅500 μm) and the porosity was geared toward high through-flow to allow electrokinetic actuation and thus avoid coupling to external pumps. Placing the monolith at the injection cross enabled firm anchoring based on its cross-shape so that no surface premodification with anchoring linkers was needed. In addition, sample loading and subsequent injection (elution) to the separation channel could be performed similar to standard ME setup. As a result, 15- to 23-fold enrichment factors were obtained already at loading (preconcentration) times as short as 25 s without sacrificing the throughput of ME analysis. The performance of the SPE-ME-ESI/MS chip was repeatable within 3.1% and 11.5% RSD (n = 3) in terms of migration time and peak height, respectively, and linear correlation was observed between the loading time and peak area. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A Computer Based Moire Technique To Measure Very Small Displacements

NASA Astrophysics Data System (ADS)

Sciammarella, Cesar A.; Amadshahi, Mansour A.; Subbaraman, B.

1987-02-01

The accuracy that can be achieved in the measurement of very small displacements in techniques such as moire, holography and speckle is limited by the noise inherent to the utilized optical devices. To reduce the noise to signal ratio, the moire method can be utilized. Two system of carrier fringes are introduced, an initial system before the load is applied and a final system when the load is applied. The moire pattern of these two systems contains the sought displacement information and the noise common to the two patterns is eliminated. The whole process is performed by a computer on digitized versions of the patterns. Examples of application are given.

Infrared Ship Classification Using A New Moment Pattern Recognition Concept

NASA Astrophysics Data System (ADS)

Casasent, David; Pauly, John; Fetterly, Donald

1982-03-01

An analysis of the statistics of the moments and the conventional invariant moments shows that the variance of the latter become quite large as the order of the moments and the degree of invariance increases. Moreso, the need to whiten the error volume increases with the order and degree, but so does the computational load associated with computing the whitening operator. We thus advance a new estimation approach to the use of moments in pattern recog-nition that overcomes these problems. This work is supported by experimental verification and demonstration on an infrared ship pattern recognition problem. The computational load associated with our new algorithm is also shown to be very low.

Interconnect patterns for printed organic thermoelectric devices with large fill factors

NASA Astrophysics Data System (ADS)

Gordiz, Kiarash; Menon, Akanksha K.; Yee, Shannon K.

2017-09-01

Organic materials can be printed into thermoelectric (TE) devices for low temperature energy harvesting applications. The output voltage of printed devices is often limited by (i) small temperature differences across the active materials attributed to small leg lengths and (ii) the lower Seebeck coefficient of organic materials compared to their inorganic counterparts. To increase the voltage, a large number of p- and n-type leg pairs is required for organic TEs; this, however, results in an increased interconnect resistance, which then limits the device output power. In this work, we discuss practical concepts to address this problem by positioning TE legs in a hexagonal closed-packed layout. This helps achieve higher fill factors (˜91%) than conventional inorganic devices (˜25%), which ultimately results in higher voltages and power densities due to lower interconnect resistances. In addition, wiring the legs following a Hilbert spacing-filling pattern allows for facile load matching to each application. This is made possible by leveraging the fractal nature of the Hilbert interconnect pattern, which results in identical sub-modules. Using the Hilbert design, sub-modules can better accommodate non-uniform temperature distributions because they naturally self-localize. These device design concepts open new avenues for roll-to-roll printing and custom TE module shapes, thereby enabling organic TE modules for self-powered sensors and wearable electronic applications.

Haemophilus is overrepresented in the nasopharynx of infants hospitalized with RSV infection and associated with increased viral load and enhanced mucosal CXCL8 responses.

PubMed

Ederveen, Thomas H A; Ferwerda, Gerben; Ahout, Inge M; Vissers, Marloes; de Groot, Ronald; Boekhorst, Jos; Timmerman, Harro M; Huynen, Martijn A; van Hijum, Sacha A F T; de Jonge, Marien I

2018-01-11

While almost all infants are infected with respiratory syncytial virus (RSV) before the age of 2 years, only a small percentage develops severe disease. Previous studies suggest that the nasopharyngeal microbiome affects disease development. We therefore studied the effect of the nasopharyngeal microbiome on viral load and mucosal cytokine responses, two important factors influencing the pathophysiology of RSV disease. To determine the relation between (i) the microbiome of the upper respiratory tract, (ii) viral load, and (iii) host mucosal inflammation during an RSV infection, nasopharyngeal microbiota profiles of RSV infected infants (< 6 months) with different levels of disease severity and age-matched healthy controls were determined by 16S rRNA marker gene sequencing. The viral load was measured using qPCR. Nasopharyngeal CCL5, CXCL10, MMP9, IL6, and CXCL8 levels were determined with ELISA. Viral load in nasopharyngeal aspirates of patients associates significantly to total nasopharyngeal microbiota composition. Healthy infants (n = 21) and RSV patients (n = 54) display very distinct microbial patterns, primarily characterized by a loss in commensals like Veillonella and overrepresentation of opportunistic organisms like Haemophilus and Achromobacter in RSV-infected individuals. Furthermore, nasopharyngeal microbiota profiles are significantly different based on CXCL8 levels. CXCL8 is a chemokine that was previously found to be indicative for disease severity and for which we find Haemophilus abundance as the strongest predictor for CXCL8 levels. The nasopharyngeal microbiota in young infants with RSV infection is marked by an overrepresentation of the genus Haemophilus. We present that this bacterium is associated with viral load and mucosal CXCL8 responses, both which are involved in RSV disease pathogenesis.

Landing strategies of athletes with an asymptomatic patellar tendon abnormality.

PubMed

Edwards, Suzi; Steele, Julie R; McGhee, Deirdre E; Beattie, Sue; Purdam, Craig; Cook, Jill L

2010-11-01

Risk factors associated with a clinical presentation of patellar tendinopathy are patellar tendon ultrasonographic abnormality (PTA) and excessive loading. It remains unknown whether characteristics of an athlete's landing technique contribute to this excessive patellar tendon loading. This study investigated whether asymptomatic athletes with and without PTA had different landing strategies and hypothesized that asymptomatic athletes with a PTA would create higher patellar tendon loading and a different lower-limb landing strategy compared with athletes with normal patellar tendons. Seven athletes with no previous history or clinical signs of patellar tendon injury with a PTA were matched to athletes with normal patellar tendons (controls). Participants performed five successful trials of a stop-jump task, which involved a simultaneous two-foot horizontal and then vertical landing. During each trial, the participants' ground reaction forces and lower-limb electromyographic data were recorded, the three-dimensional kinematics measured, and the peak patellar tendon force calculated by dividing the net knee joint moment by the patellar tendon moment arm. Significant between-group differences in landing technique were mostly observed during the horizontal landing phase. Participants with a PTA created similar patellar tendon loading to the controls, but with altered sequencing, by landing with significantly greater knee flexion and extending their hips while the controls flexed their hips as they landed, reflecting a different muscle recruitment order compared with the PTA group. The crucial part in the development of PTA and, in turn, patellar tendinopathy may not be the magnitude of the patellar tendon load but rather the loading patterns. This research provides clinicians with important landing assessment criteria against which to identify athletes at risk of developing patellar tendinopathy.

Environmental impact of irrigation in la violada district (Spain): I. Salt export patterns.

PubMed

Isidoro, D; Quílez, D; Aragüés, R

2006-01-01

Salt loading in irrigation return flows contributes to the salinization of the receiving water bodies, particularly when originated in salt-affected areas as frequently found in the middle Ebro River basin (Spain). We determined the salt loading in La Violada Gully from the total dissolved solids (TDS) and flows (Q) during the 1995 to 1998 hydrological years. Since this gully collects flows from various sources, an end-member mixing analysis (EMMA) was performed to quantify the drainage flow from La Violada Irrigation District (VID). Three flow components were identified in La Violada Gully: drainage waters from VID (Qd); tail-waters from irrigation ditches, spill-over, and seepage from the Monegros Canal (Qo); and ground water inflows (Qg) originating in the dryland watershed. Gypsum in the soils of VID was the main source for salts in La Violada Gully (flow-weighted mean TDS=1720 mg L-1, dominated by sulfate and calcium). The contribution of Qg to the total gully flow during the 1996 irrigation season was low (6.5% of the total flow). The 1995 to 1998 annual salt load average in La Violada Gully was 78 628 Mg, 71% of which was exported during the irrigation season. The 1995 to 1998 irrigation season salt load average in Qd was 43 015 Mg (77% of the total load). Thus, irrigated agriculture in VID was the main source of salt loading in this gully, with a yield of 11.1 Mg of salts per hectare of irrigated land for the irrigation season. Efficient irrigation systems and irrigation management practices that reduce Qd are key factors for controlling off-site salt pollution of these gypsum-rich irrigated areas.

Real-time polarization imaging algorithm for camera-based polarization navigation sensors.

PubMed

Lu, Hao; Zhao, Kaichun; You, Zheng; Huang, Kaoli

2017-04-10

Biologically inspired polarization navigation is a promising approach due to its autonomous nature, high precision, and robustness. Many researchers have built point source-based and camera-based polarization navigation prototypes in recent years. Camera-based prototypes can benefit from their high spatial resolution but incur a heavy computation load. The pattern recognition algorithm in most polarization imaging algorithms involves several nonlinear calculations that impose a significant computation burden. In this paper, the polarization imaging and pattern recognition algorithms are optimized through reduction to several linear calculations by exploiting the orthogonality of the Stokes parameters without affecting precision according to the features of the solar meridian and the patterns of the polarized skylight. The algorithm contains a pattern recognition algorithm with a Hough transform as well as orientation measurement algorithms. The algorithm was loaded and run on a digital signal processing system to test its computational complexity. The test showed that the running time decreased to several tens of milliseconds from several thousand milliseconds. Through simulations and experiments, it was found that the algorithm can measure orientation without reducing precision. It can hence satisfy the practical demands of low computational load and high precision for use in embedded systems.

Control circuit maintains unity power factor of reactive load

NASA Technical Reports Server (NTRS)

Kramer, M.; Martinage, L. H.

1966-01-01

Circuit including feedback control elements automatically corrects the power factor of a reactive load. It maintains power supply efficiency where negative load reactance changes and varies by providing corrective error signals to the control windings of a power supply transformer.

14 CFR 25.531 - Hull and main float takeoff condition.

Code of Federal Regulations, 2011 CFR

2011-01-01

... wing lift is assumed to be zero; and (b) A downward inertia load, corresponding to a load factor computed from the following formula, must be applied: EC28SE91.038 where— n=inertia load factor; C TO...

14 CFR 25.531 - Hull and main float takeoff condition.

Code of Federal Regulations, 2013 CFR

2013-01-01

... wing lift is assumed to be zero; and (b) A downward inertia load, corresponding to a load factor computed from the following formula, must be applied: EC28SE91.038 where— n=inertia load factor; C TO...

14 CFR 25.531 - Hull and main float takeoff condition.

Code of Federal Regulations, 2014 CFR

2014-01-01

... wing lift is assumed to be zero; and (b) A downward inertia load, corresponding to a load factor computed from the following formula, must be applied: EC28SE91.038 where— n=inertia load factor; C TO...

14 CFR 25.531 - Hull and main float takeoff condition.

Code of Federal Regulations, 2012 CFR

2012-01-01

... wing lift is assumed to be zero; and (b) A downward inertia load, corresponding to a load factor computed from the following formula, must be applied: EC28SE91.038 where— n=inertia load factor; C TO...

A neural network approach for determining gait modifications to reduce the contact force in knee joint implant.

PubMed

Ardestani, Marzieh Mostafavizadeh; Chen, Zhenxian; Wang, Ling; Lian, Qin; Liu, Yaxiong; He, Jiankang; Li, Dichen; Jin, Zhongmin

2014-10-01

There is a growing interest in non-surgical gait rehabilitation treatments to reduce the loading in the knee joint. In particular, synergetic kinematic changes required for joint offloading should be determined individually for each subject. Previous studies for gait rehabilitation designs are typically relied on a "trial-and-error" approach, using multi-body dynamic (MBD) analysis. However MBD is fairly time demanding which prevents it to be used iteratively for each subject. This study employed an artificial neural network to develop a cost-effective computational framework for designing gait rehabilitation patterns. A feed forward artificial neural network (FFANN) was trained based on a number of experimental gait trials obtained from literature. The trained network was then hired to calculate the appropriate kinematic waveforms (output) needed to achieve desired knee joint loading patterns (input). An auxiliary neural network was also developed to update the ground reaction force and moment profiles with respect to the predicted kinematic waveforms. The feasibility and efficiency of the predicted kinematic patterns were then evaluated through MBD analysis. Results showed that FFANN-based predicted kinematics could effectively decrease the total knee joint reaction forces. Peak values of the resultant knee joint forces, with respect to the bodyweight (BW), were reduced by 20% BW and 25% BW in the midstance and the terminal stance phases. Impulse values of the knee joint loading patterns were also decreased by 17% BW*s and 24%BW*s in the corresponding phases. The FFANN-based framework suggested a cost-effective forward solution which directly calculated the kinematic variations needed to implement a given desired knee joint loading pattern. It is therefore expected that this approach provides potential advantages and further insights into knee rehabilitation designs. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.

Non-medical use of prescription drugs and its association with socio-demographic characteristics, dietary pattern, and perceived academic load and stress in college students in Puerto Rico.

PubMed

Betancourt, Jesmari; Ríos, Josué L; Pagán, Ideliz; Fabián, Carla; González, Anaisa M; Cruz, Sonia Y; González, Michael J; Rivera, Winna T; Palacios, Cristina

2013-06-01

Stress can have deleterious effects on health and academic performance. Common stress-relieving activities among college students include the non-medical use of prescription drugs (NMUPD). The aim of this study was to determine the associations between self-perceived academic load and stress, NMUPD (stimulants, depressants, and sleeping medication), and dietary pattern in college students in PR. A questionnaire to evaluate academic load and stress, NMUPD, and dietary pattern was used on a representative sample of 275 first- and second-year students from one campus. In total, 27.6% reported NMUPD in the past 6 months, with higher use among students aged 21-30 years (93.4%) than in those aged 31-53 years (6.6%; p=0.062). Those with high levels of stress had higher NMUPD (42.1%) than did those with low (26.3%) or moderate (31.6%) stress levels, after controlling for age and sex (p=0.03). Among those who reported NMUPD over the previous 6 months, 74% reported that such use was effective as a coping strategy, and 35% reported that it helped them to improve academic performance. Although no significant association was found between NMUPD and dietary pattern, 57% of the participants reported that their appetites decreased when they engaged in NMUPD. To our knowledge, this is the first study that has associated self-perceived academic load and stress, NMUPD, and dietary pattern among college students in Puerto Rico. NMUPD's prevalence was 27.6%, which prevalence appeared to be higher in students aged 21-30 years than in those of any other age. High levels of stress were significantly related to high NMUPD in this sample.

The mechanism of bolt loading

NASA Technical Reports Server (NTRS)

Lee, H. M.

1992-01-01

It is shown that the mechanism of bolt loading for preloaded fasteners can be effectively portrayed through simple spring models and some algebraic manipulations. Understanding schematically what is involved in such joints provides insight into the distribution of loads. The developed equations confirm that for both symmetric and nonsymmetric joints the loading plane factor and the stiffness factor directly affect the load seen in preloaded fasteners. The manner in which an external loading is transferred through the joint can be explained as energy dissipated in the various springs of both the abutment and the bolt itself.

Isolating Age-Group Differences in Working Memory Load-Related Neural Activity: Assessing the Contribution of Working Memory Capacity Using a Partial-Trial fMRI Method

PubMed Central

Bennett, Ilana J.; Rivera, Hannah G.; Rypma, Bart

2013-01-01

Previous studies examining age-group differences in working memory load-related neural activity have yielded mixed results. When present, age-group differences in working memory capacity are frequently proposed to underlie these neural effects. However, direct relationships between working memory capacity and working memory load-related activity have only been observed in younger adults. These relationships remain untested in healthy aging. Therefore, the present study examined patterns of working memory load-related activity in 22 younger and 20 older adults and assessed the contribution of working memory capacity to these load-related effects. Participants performed a partial-trial delayed response item recognition task during functional magnetic resonance imaging. In this task, participants encoded either 2 or 6 letters, maintained them during a delay, and then indicated whether a probe was present in the memory set. Behavioral results revealed faster and more accurate responses to load 2 versus 6, with age-group differences in this load condition effect for the accuracy measure. Neuroimaging results revealed one region (medial superior frontal gyrus) that showed age-group differences in load-related activity during the retrieval period, with less (greater) neural activity for the low versus high load condition in younger (older) adults. Furthermore, for older adults, load-related activity did not vary as a function of working memory capacity. Thus, working memory-related activity varies with healthy aging, but these patterns are not due solely to working memory capacity. Neurocognitive aging theories that feature capacity will need to account for these results. PMID:23357076

Selective impairment of auditory selective attention under concurrent cognitive load.

PubMed

Dittrich, Kerstin; Stahl, Christoph

2012-06-01

Load theory predicts that concurrent cognitive load impairs selective attention. For visual stimuli, it has been shown that this impairment can be selective: Distraction was specifically increased when the stimulus material used in the cognitive load task matches that of the selective attention task. Here, we report four experiments that demonstrate such selective load effects for auditory selective attention. The effect of two different cognitive load tasks on two different auditory Stroop tasks was examined, and selective load effects were observed: Interference in a nonverbal-auditory Stroop task was increased under concurrent nonverbal-auditory cognitive load (compared with a no-load condition), but not under concurrent verbal-auditory cognitive load. By contrast, interference in a verbal-auditory Stroop task was increased under concurrent verbal-auditory cognitive load but not under nonverbal-auditory cognitive load. This double-dissociation pattern suggests the existence of different and separable verbal and nonverbal processing resources in the auditory domain.

Proceedings of the European Conference (4th), Held in Wageningen, The Netherlands on March 21-23, 1989. Volume 2

DTIC Science & Technology

1989-03-01

comparison between the two. Tyre self-excited vibration can be caused by lack of uniforuity and/or out-of-balance. The authors suggest that driving ... safety is best described by the ’Dynamic Load Factor’ which relates the ainimum rolling dynamic load to the static tyre load. Dynamic Load Factors are

14 CFR 25.499 - Nose-wheel yaw and steering.

Code of Federal Regulations, 2012 CFR

2012-01-01

... steering. (a) A vertical load factor of 1.0 at the airplane center of gravity, and a side component at the... structure forward of the center of gravity must be designed for the following loads: (1) A vertical load factor at the center of gravity of 1.0. (2) A forward acting load at the airplane center of gravity of 0...

14 CFR 25.499 - Nose-wheel yaw and steering.

Code of Federal Regulations, 2013 CFR

2013-01-01

... steering. (a) A vertical load factor of 1.0 at the airplane center of gravity, and a side component at the... structure forward of the center of gravity must be designed for the following loads: (1) A vertical load factor at the center of gravity of 1.0. (2) A forward acting load at the airplane center of gravity of 0...

Creep crack growth by grain boundary cavitation under monotonic and cyclic loading

NASA Astrophysics Data System (ADS)

Wen, Jian-Feng; Srivastava, Ankit; Benzerga, Amine; Tu, Shan-Tung; Needleman, Alan

2017-11-01

Plane strain finite deformation finite element calculations of mode I crack growth under small scale creep conditions are carried out. Attention is confined to isothermal conditions and two time histories of the applied stress intensity factor: (i) a monononic increase to a plateau value subsequently held fixed; and (ii) a cyclic time variation. The crack growth calculations are based on a micromechanics constitutive relation that couples creep deformation and damage due to grain boundary cavitation. Grain boundary cavitation, with cavity growth due to both creep and diffusion, is taken as the sole failure mechanism contributing to crack growth. The influence on the crack growth rate of loading history parameters, such as the magnitude of the applied stress intensity factor, the ratio of the applied minimum to maximum stress intensity factors, the loading rate, the hold time and the cyclic loading frequency, are explored. The crack growth rate under cyclic loading conditions is found to be greater than under monotonic creep loading with the plateau applied stress intensity factor equal to its maximum value under cyclic loading conditions. Several features of the crack growth behavior observed in creep-fatigue tests naturally emerge, for example, a Paris law type relation is obtained for cyclic loading.

Exact solutions for postbuckling of a graded porous beam

NASA Astrophysics Data System (ADS)

Ma, L. S.; Ou, Z. Y.

2018-06-01

An exact, closed-form solution for the postbuckling responses of graded porous beams subjected to axially loading is obtained. It was assumed that the properties of the graded porous materials vary continuously through thickness of the beams, the equations governing the axial and transverse deformations are derived based on the classical beam theory and the physical neutral surface concept. The two equations are reduced to a single nonlinear fourth-order integral-differential equation governing the transverse deformations. The nonlinear equation is directly solved without any use of approximation and a closed-form solution for postbuckled deformation is obtained as a function of the applied load. The exact solutions explicitly describe the nonlinear equilibrium paths of the buckled beam and thus are able to provide insight into deformation problems. Based on the exact solutions obtained herein, the effects of various factors such as porosity distribution pattern, porosity coefficient and boundary conditions on postbuckling behavior of graded porous beams have been investigated.

MCM interference during licensing of DNA replication in Xenopus egg extracts-Possible Role of a C-terminal region of MCM3.

PubMed

Mimura, Satoru; Kubota, Yumiko; Takisawa, Haruhiko

2018-01-01

The minichromosome maintenance (MCM) complex, consisting of six subunits, Mcm2-7, is loaded onto replication origins through loading factors (origin recognition complex [ORC], Cdc6, and Cdt1) and forms an MCM double hexamer that licenses the initiation of DNA replication. Previous studies with Xenopus egg extracts showed that loading factors, especially Cdc6, dissociate from chromatin on MCM loading, but the molecular mechanism and physiological significance remain largely unknown. Using a cell-free system for MCM loading onto plasmid DNA in Xenopus egg extracts, we found that MCM loaded onto DNA prevents DNA binding of the loading factors ORC, Cdc6, and Cdt1. We further report that a peptide of the C-terminal region of MCM3 (MCM3-C), previously implicated in the initial association with ORC/Cdc6 in budding yeast, prevents ORC/Cdc6/Cdt1 binding to DNA in the absence of MCM loading. ATP-γ-S suppresses inhibitory activities of both the MCM loaded onto DNA and the MCM3-C peptide. Other soluble factors in the extract, but neither MCM nor Cdt1, are required for the activity. Conservation of the amino acid sequences of MCM3-C and its activity in vertebrates implies a novel negative autoregulatory mechanism that interferes with MCM loading in the vicinity of licensed origins to ensure proper origin licensing.

14 CFR 27.337 - Limit maneuvering load factor.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Limit maneuvering load factor. 27.337 Section 27.337 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Strength Requirements Flight Loads § 27.337...

The Effect of Fatigue Cracks on Fastener Flexibility, Load Distribution and Fatigue Crack Growth

DTIC Science & Technology

2012-05-01

fastener will transfer within a given fastener pattern. iv iv However, current methods do not account for the change in flexibility at a fastener...affects the growth of the crack. Thus, as the effect of the crack starts to impact the load transfer of the joint there is a need to account for...not account for spectrum loading but typically were cycled from 1g to limit or maximum flight load and then correlated to measured usage using

Comparison Virtual Landing Gear Drop Test for Commuter Aircraft Utilize MSC ADAMS And Solidworks Motion Analysis

NASA Astrophysics Data System (ADS)

Hidayat, Dony; Istiyanto, Jos; Agus Sumarsono, Danardono

2018-04-01

Loads at main landing gear while touchdown impact is function of aircraft weight and ground reaction load factor. In regulation states ground reaction load factor at Vsink = 3.05 m/s is below 3. Contact/impact force from simulation using MSC ADAMS is 94680 N, while using Solidworks Motion Analysis is 97691 N. The difference between MSC ADAMS and Solidworks Motion Analysis is 3.08%. The ground reaction load factor in MSC ADAMS is 2.78 while in Solidworks Motion Analysis is 2.87.

Likelihood-Based Confidence Intervals in Exploratory Factor Analysis

ERIC Educational Resources Information Center

Oort, Frans J.

2011-01-01

In exploratory or unrestricted factor analysis, all factor loadings are free to be estimated. In oblique solutions, the correlations between common factors are free to be estimated as well. The purpose of this article is to show how likelihood-based confidence intervals can be obtained for rotated factor loadings and factor correlations, by…

On the Relations among Regular, Equal Unique Variances, and Image Factor Analysis Models.

ERIC Educational Resources Information Center

Hayashi, Kentaro; Bentler, Peter M.

2000-01-01

Investigated the conditions under which the matrix of factor loadings from the factor analysis model with equal unique variances will give a good approximation to the matrix of factor loadings from the regular factor analysis model. Extends the results to the image factor analysis model. Discusses implications for practice. (SLD)

Pullout Performances of Grouted Rockbolt Systems with Bond Defects

NASA Astrophysics Data System (ADS)

Xu, Chang; Li, Zihan; Wang, Shanyong; Wang, Shuren; Fu, Lei; Tang, Chunan

2018-03-01

This paper presents a numerical study on the pullout behaviour of fully grouted rockbolts with bond defects. The cohesive zone model (CZM) is adopted to model the bond-slip behaviour between the rockbolt and grout material. Tensile tests were also conducted to validate the numerical model. The results indicate that the defect length can obviously influence the load and stress distributions along the rockbolt as well as the load-displacement response of the grouted system. Moreover, a plateau in the stress distribution forms due to the bond defect. The linear limit and peak load of the load-displacement response decrease as the defect length increases. A bond defect located closer to the loaded end leads to a longer nonlinear stage in the load-displacement response. However, the peak loads measured from the specimens made with various defect locations are almost approximately the same. The peak load for a specimen with the defects equally spaced along the bolt is higher than that for a specimen with defects concentrated in a certain zone, even with the same total defect length. Therefore, the dispersed pattern of bond defects would be much safer than the concentrated pattern. For the specimen with dispersed defects, the peak load increases with an increase in the defect spacing, even if the total defect length is the same. The peak load for a grouted rockbolt system with defects increases with an increases in the bolt diameter. This work leads to a better understanding of the load transfer mechanism for grouted rockbolt systems with bond defects, and paves the way towards developing a general evaluation method for damaged rockbolt grouted systems.

Psychiatric disorders in preschoolers: the structure of DSM-IV symptoms and profiles of comorbidity.

PubMed

Wichstrøm, Lars; Berg-Nielsen, Turid Suzanne

2014-07-01

Psychiatric disorders have been increasingly recognized in preschool children; at present, however, we know comparatively less about how well current diagnostic manuals capture the symptoms described in this age group and how comorbidity is patterned. Therefore, this study aimed to investigate whether the symptoms defined by the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) load on their respective disorders, examine whether individual symptoms exist that load particularly high or low on the disorder they allegedly define, and analyze how comorbidity clusters in individual children. Parents of a community sample of Norwegian 4-year-olds (N = 995) were interviewed using the Preschool Age Psychiatric Assessment. A confirmatory factor analysis (CFA) and a latent profile analysis (LPA) were performed on the symptoms of seven DSM disorders: attention-deficit/hyperactivity disorder (ADHD), oppositional defiant disorder, conduct disorder, major depressive disorder (MDD), generalized anxiety disorder (GAD), social phobia, and separation anxiety disorder. The results showed that the CFA solution that closely resembled the disorders delineated in the DSM-IV fitted the data best. However, vegetative symptoms did not define preschool depression. The LPA identified nine symptom profiles among preschoolers, of which four showed evidence of psychopathology: comorbid MDD/GAD ? ADHD combined type, comorbid MDD/GAD ? ADHD hyperactive/impulsive type, separation anxiety only, and social phobia only. In conclusion, the symptoms observed in preschoolers fit the DSM-IV well, and comorbidity followed specific patterns.

Dynamic parameters of three-point crutch gait in female patients after total hip arthroplasty.

PubMed

Murawa, Michał; Dworak, Lechosław B; Kabaciński, Jarosław; Syczewska, Małgorzata; Rzepnicka, Agata

2016-01-01

Patient recovery after a surgical procedure depends, among other factors, on the amount of the body weight with which patient loads lower limb. Research studies report different results of the degree of body weight with which lower limb is loaded during three-point crutch gait. The aim of this study was to evaluate the level of the ground reaction forces (GRF) during crutch gait used by patients after total hip arthroplasty (THA) in the first week after discharge from the orthopaedic units. Ten female patients diagnosed with primary unilateral coxarthrosis participated in a single measurement session. In order to record kinematic and dynamic variables of this gait pattern motion analysis system was used together with two force plates. The static test of body weight distribution between lower limbs was performed on a dual-top stabilometric plate. The average peak values of loading on the operated (O) limb during mid stance and terminal stance of three-point crutch gait were 64.6% and 64.3% of body weight (BW), respectively, whereas in the case of the nonoperated (NO) limb 103.5%BW and 108.8%BW, respectively. The maximum loads on the crutches were significantly higher (by 9%BW) on the NO side as compared to the O side ( p < 0.05). During the static test, average values of body weight distribution on the O and NO limb were 36%BW and 64%BW, respectively. The patients showed surprisingly similar level of loading on the O limb. The weight bearing on the O limb was lower during static trial than during three-point crutch gait.

Ontogenetic changes in the internal and external morphology of the ilium in modern humans

PubMed Central

Abel, Richard; Macho, Gabriele A

2011-01-01

Trabecular architecture forms an important structural component of bone and, depending on the loading conditions encountered during life, is organised in a systematic, bone- and species-specific manner. However, recent studies suggested that gross trabecular arrangement (e.g. density distribution), like overall bone shape, is predetermined and/or affected by factors other than loading and perhaps less plastic than commonly assumed. To explore this issue further, the present cross-sectional ontogenetic study investigated morphological changes in external bone shape in relation to changes in trabecular bundle orientation and anisotropy. Radiographs of 73 modern human ilia were assessed using radiographic and Geometric Morphometric techniques. The study confirmed the apparently strong predetermination of trabecular bundle development, i.e. prior to external loading, although loading clearly also had an effect on overall morphology. For example, the sacro-pubic bundle, which follows the path of load transmission from the auricular surface to the acetabulum, is well defined and shows relatively high levels of anisotropy from early stages of development; the situation for the ischio-iliac strut is similar. However, while the sacro-pubic strut retains a constant relationship with the external landmarks defining the joint surfaces, the ischio-iliac bundle changes its relationship with the external landmarks and becomes aligned with the iliac tubercle only during late adolescence/early adulthood. It is tentatively proposed that the rearrangement of the ischio-iliac strut may reflect a change in locomotor pattern and/or a shift in positional behavior with increasing mass after growth of external bone dimensions has slowed/ceased. PMID:21323915

Bootstrap Confidence Intervals for Ordinary Least Squares Factor Loadings and Correlations in Exploratory Factor Analysis

ERIC Educational Resources Information Center

Zhang, Guangjian; Preacher, Kristopher J.; Luo, Shanhong

2010-01-01

This article is concerned with using the bootstrap to assign confidence intervals for rotated factor loadings and factor correlations in ordinary least squares exploratory factor analysis. Coverage performances of "SE"-based intervals, percentile intervals, bias-corrected percentile intervals, bias-corrected accelerated percentile…

High glycemic load diet, milk and ice cream consumption are related to acne vulgaris in Malaysian young adults: a case control study.

PubMed

Ismail, Noor Hasnani; Manaf, Zahara Abdul; Azizan, Noor Zalmy

2012-08-16

The role of dietary factors in the pathophysiology of acne vulgaris is highly controversial. Hence, the aim of this study was to determine the association between dietary factors and acne vulgaris among Malaysian young adults. A case-control study was conducted among 44 acne vulgaris patients and 44 controls aged 18 to 30 years from October 2010 to January 2011. Comprehensive acne severity scale (CASS) was used to determine acne severity. A questionnaire comprising items enquiring into the respondent's family history and dietary patterns was distributed. Subjects were asked to record their food intake on two weekdays and one day on a weekend in a three day food diary. Anthropometric measurements including body weight, height and body fat percentage were taken. Acne severity was assessed by a dermatologist. Cases had a significantly higher dietary glycemic load (175 ± 35) compared to controls (122 ± 28) (p < 0.001). The frequency of milk (p < 0.01) and ice-cream (p < 0.01) consumptions was significantly higher in cases compared to controls. Females in the case group had a higher daily energy intake compared to their counterparts in the control group, 1812 ± 331 and 1590 ± 148 kcal respectively (p < 0.05). No significant difference was found in other nutrient intakes, Body Mass Index, and body fat percentage between case and control groups (p > 0.05). Glycemic load diet and frequencies of milk and ice cream intake were positively associated with acne vulgaris.

Factors Influencing Running-Related Musculoskeletal Injury Risk Among U.S. Military Recruits.

PubMed

Molloy, Joseph M

2016-06-01

Running-related musculoskeletal injuries among U.S. military recruits negatively impact military readiness. Low aerobic fitness, prior injury, and weekly running distance are known risk factors. Physical fitness screening and remedial physical training (or discharging the most poorly fit recruits) before entry-level military training have tended to reduce injury rates while decreasing attrition, training, and medical costs. Incorporating anaerobic running sessions into training programs can offset decreased weekly running distance and decrease injury risk. Varying lower extremity loading patterns, stride length or cadence manipulation, and hip stability/strengthening programming may further decrease injury risk. No footstrike pattern is ideal for all runners; transitioning to forefoot striking may reduce risk for hip, knee, or tibial injuries, but increase risk for calf, Achilles, foot or ankle injuries. Minimal evidence associates running surfaces with injury risk. Footwear interventions should focus on proper fit and comfort; the evidence does not support running shoe prescription per foot type to reduce injury risk among recruits. Primary injury mitigation efforts should focus on physical fitness screening, remedial physical training (or discharge for unfit recruits), and continued inclusion of anaerobic running sessions to offset decreased weekly running distance. Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.

Improving the detectability and imaging capability of ground penetrating radar using novel antenna concepts

NASA Astrophysics Data System (ADS)

Koyadan Koroth, Ajith; Bhattacharya, Amitabha

2017-04-01

Antennas are key components of Ground Penetrating Radar (GPR) instrumentation. A carefully designed antenna can improve the detectability and imaging capability of a GPR to a great extent without changing the other instrumentations. In this work, we propose four different types of antennas for GPR. They are modifications of a conventional bowtie antenna with great improvement in performance parameters. The designed antennas has also been tested in a stepped frequency type GPR and two dimensional scan images of various targets are presented. Bowtie antennas have been traditionally employed in GPR for its wide impedance bandwidth and radiation properties. The researchers proposed resistive loading to improve the bandwidth of the bowtie antenna and for low ringing pulse radiation. But this method was detrimental for antenna gain and efficiency. Bowtie antennas have a very wide impedance bandwidth. But the useful bandwidth of the antenna has been limited by the radiation pattern bandwidth. The boresight gain of bowtie antennas are found to be unstable beyond a 4:1 bandwidth. In this work, these problems have been addressed and maximum usable bandwidth for the bowtie antennas has been achieved. In this work, four antennas have been designed: namely, 1.) RC loaded bowtie antennas, 2.) RC loaded bowtie with metamaterial lens, 3.) Loop loaded bowtie, 4.) Loop loaded bowtie with directors. The designed antennas were characterized for different parameters like impedance bandwidth, radiation pattern and, gain. In antenna 1, a combined resistive-capacitive loading has been applied by periodic slot cut on the arms of the bowtie and pasting a planar graphite sheet over it. Graphite having a less conductance compared to copper acts as resistive loading. This would minimize the losses compared to lumped resistive loading. The antenna had a 10:1 impedance bandwidth and, a 5:1 pattern bandwidth. In antenna 2, a metamaterial lens has been designed to augment the antenna 1, to improve the forward gain. This antenna had the same impedance bandwidth of 10:1 while pattern bandwidth has been raised to 7:1. In antenna 3, a loop loaded bowtie antenna has been designed. This antenna do not employ any kind of resistive loading, yet achieves an impedance bandwidth of 11:1 and also a usable bandwidth of 11:1. The antenna 4 employs concentric offset loops which acts as directors to improve the directivity. This antenna achieved an impedance bandwidth and a pattern bandwidth of 13:1. All the antennas have a maximum size of about 0.3λ at lowest operating frequency. An experimental stepped frequency type GPR has been constructed to study the suitability of the fabricated antennas in detecting buried targets. Four experiments have been conducted viz. 1.) To detect a metallic pipe of 1in diameter, 2.) To detect a metallic pipe of 2in diameter 3.) To detect dry bamboo, 3.) To detect rebar in concrete. The detectability and imaging capability of GPR has been found to be improving from antenna 1 to 4.

Perceptual load corresponds with factors known to influence visual search

PubMed Central

Roper, Zachary J. J.; Cosman, Joshua D.; Vecera, Shaun P.

2014-01-01

One account of the early versus late selection debate in attention proposes that perceptual load determines the locus of selection. Attention selects stimuli at a late processing level under low-load conditions but selects stimuli at an early level under high-load conditions. Despite the successes of perceptual load theory, a non-circular definition of perceptual load remains elusive. We investigated the factors that influence perceptual load by using manipulations that have been studied extensively in visual search, namely target-distractor similarity and distractor-distractor similarity. Consistent with previous work, search was most efficient when targets and distractors were dissimilar and the displays contained homogeneous distractors; search became less efficient when target-distractor similarity increased irrespective of display heterogeneity. Importantly, we used these same stimuli in a typical perceptual load task that measured attentional spill-over to a task-irrelevant flanker. We found a strong correspondence between search efficiency and perceptual load; stimuli that generated efficient searches produced flanker interference effects, suggesting that such displays involved low perceptual load. Flanker interference effects were reduced in displays that produced less efficient searches. Furthermore, our results demonstrate that search difficulty, as measured by search intercept, has little bearing on perceptual load. These results suggest that perceptual load might be defined in part by well-characterized, continuous factors that influence visual search. PMID:23398258

Quantify work load and muscle functional activation patterns in neck-shoulder muscles of female sewing machine operators using surface electromyogram.

PubMed

Zhang, Fei-Ruo; He, Li-Hua; Wu, Shan-Shan; Li, Jing-Yun; Ye, Kang-Pin; Wang, Sheng

2011-11-01

Work-related musculoskeletal disorders (WMSDs) have high prevalence in sewing machine operators employed in the garment industry. Long work duration, sustained low level work and precise hand work are the main risk factors of neck-shoulder disorders for sewing machine operators. Surface electromyogram (sEMG) offers a valuable tool to determine muscle activity (internal exposure) and quantify muscular load (external exposure). During sustained and/or repetitive muscle contractions, typical changes of muscle fatigue in sEMG, as an increase in amplitude or a decrease as a shift in spectrum towards lower frequencies, can be observed. In this paper, we measured and quantified the muscle load and muscular activity patterns of neck-shoulder muscles in female sewing machine operators during sustained sewing machine operating tasks using sEMG. A total of 18 healthy women sewing machine operators volunteered to participate in this study. Before their daily sewing machine operating task, we measured the maximal voluntary contractions (MVC) and 20%MVC of bilateral cervical erector spinae (CES) and upper trapezius (UT) respectively, then the sEMG signals of bilateral UT and CES were monitored and recorded continuously during 200 minutes of sustained sewing machine operating simultaneously which equals to 20 time windows with 10 minutes as one time window. After 200 minutes' work, we retest 20%MVC of four neck-shoulder muscles and recorded the sEMG signals. Linear analysis, including amplitude probability distribution frequency (APDF), amplitude analysis parameters such as roof mean square (RMS) and spectrum analysis parameter as median frequency (MF), were used to calculate and indicate muscle load and muscular activity of bilateral CES and UT. During 200 minutes of sewing machine operating, the median load for the left cervical erector spinae (LCES), right cervical erector spinae (RCES), left upper trapezius (LUT) and right upper trapezius (RUT) were 6.78%MVE, 6.94%MVE, 6.47%MVE and 5.68%MVE, respectively. Work load of right muscles are significantly higher than that of the left muscles (P < 0.05); sEMG signal analysis of isometric contractions indicated that the amplitude value before operating was significantly higher than that of after work (P < 0.01), and the spectrum value of bilateral CES and UT were significantly lower than those of after work (P < 0.01); according to the sEMG signal data of 20 time windows, with operating time pass by, the muscle activity patterns of bilateral CES and UT showed dynamic changes, the maximal amplitude of LCES, RCES, LUT occurred at the 20th time window, RUT at 16th time window, spectrum analysis showed that the lower value happened at 7th, 16th, 20th time windows. Female sewing machine operators were exposed to high sustained static load on bilateral neck-shoulder muscles; left neck and shoulder muscles were held in more static positions; the 7th, 16th, and 20th time windows were muscle fatigue period that ergonomics intervention can protocol at these periods.

[Comparison of kinematic and kinetic parameters between the locomotion patterns in nordic walking, walking and running].

PubMed

Kleindienst, F I; Michel, K J; Schwarz, J; Krabbe, B

2006-03-01

Based on a higher cardio-pulmonary and cardio-vascular benefit and a promised reduction of mechanical load of the musculoskeletal system Nordic Walking (NW) shows an increased market potential. The present study should investigate whether there are biomechanical differences between the locomotion patterns NW, walking and running. Moreover possible resultant load differences should be determined. Eleven subjects, who were already experienced with the NW-technique, participated in this experiment. The kinematic data were collected using two high-speed camera systems from posterior and from lateral at the same time. Simultaneously the ground reaction forces were recorded. The kinematic and the kinetic data reveal differences between the three analyzed locomotion patterns. For NW as well as walking the mechanical load of the lower extremity is lower compared to running. None of the kinematic parameters suggest a "physiological benefit" of NW compared to walking. Moreover NW shows higher vertical and horizontal forces during landing. Exclusively the lower vertical force peak during push off indicates a lower mechanical load for NW in comparison to walking. Consequently it is questionable is NW -- based on its promised "biomechanical benefits" compared to walking -- should be still recommended for overweight people and for people with existing musculoskeletal problems of the lower limb.

An Efficient Framework Model for Optimizing Routing Performance in VANETs.

PubMed

Al-Kharasani, Nori M; Zulkarnain, Zuriati Ahmad; Subramaniam, Shamala; Hanapi, Zurina Mohd

2018-02-15

Routing in Vehicular Ad hoc Networks (VANET) is a bit complicated because of the nature of the high dynamic mobility. The efficiency of routing protocol is influenced by a number of factors such as network density, bandwidth constraints, traffic load, and mobility patterns resulting in frequency changes in network topology. Therefore, Quality of Service (QoS) is strongly needed to enhance the capability of the routing protocol and improve the overall network performance. In this paper, we introduce a statistical framework model to address the problem of optimizing routing configuration parameters in Vehicle-to-Vehicle (V2V) communication. Our framework solution is based on the utilization of the network resources to further reflect the current state of the network and to balance the trade-off between frequent changes in network topology and the QoS requirements. It consists of three stages: simulation network stage used to execute different urban scenarios, the function stage used as a competitive approach to aggregate the weighted cost of the factors in a single value, and optimization stage used to evaluate the communication cost and to obtain the optimal configuration based on the competitive cost. The simulation results show significant performance improvement in terms of the Packet Delivery Ratio (PDR), Normalized Routing Load (NRL), Packet loss (PL), and End-to-End Delay (E2ED).

Stress-intensity factors and crack-opening displacements for round compact specimens. [fracture toughness of metallic materials

NASA Technical Reports Server (NTRS)

Newman, J. C., Jr.

1979-01-01

A two dimensional, boundary collocation stress analysis was used to analyze various round compact specimens. The influence of the round external boundary and of pin-loaded holes on stress intensity factors and crack opening displacements was determined as a function of crack-length-to-specimen-width ratios. A wide-range equation for the stress intensity factors was developed. Equations for crack-surface displacements and load-point displacements were also developed. In addition, stress intensity factors were calculated from compliance methods to demonstrate that load-displacement records must be made at the loading points and not along the crack line for crack-length-to-specimen-width ratios less than about 0.4.

Performance of a cognitive load inventory during simulated handoffs: Evidence for validity.

PubMed

Young, John Q; Boscardin, Christy K; van Dijk, Savannah M; Abdullah, Ruqayyah; Irby, David M; Sewell, Justin L; Ten Cate, Olle; O'Sullivan, Patricia S

2016-01-01

Advancing patient safety during handoffs remains a public health priority. The application of cognitive load theory offers promise, but is currently limited by the inability to measure cognitive load types. To develop and collect validity evidence for a revised self-report inventory that measures cognitive load types during a handoff. Based on prior published work, input from experts in cognitive load theory and handoffs, and a think-aloud exercise with residents, a revised Cognitive Load Inventory for Handoffs was developed. The Cognitive Load Inventory for Handoffs has items for intrinsic, extraneous, and germane load. Students who were second- and sixth-year students recruited from a Dutch medical school participated in four simulated handoffs (two simple and two complex cases). At the end of each handoff, study participants completed the Cognitive Load Inventory for Handoffs, Paas' Cognitive Load Scale, and one global rating item for intrinsic load, extraneous load, and germane load, respectively. Factor and correlational analyses were performed to collect evidence for validity. Confirmatory factor analysis yielded a single factor that combined intrinsic and germane loads. The extraneous load items performed poorly and were removed from the model. The score from the combined intrinsic and germane load items associated, as predicted by cognitive load theory, with a commonly used measure of overall cognitive load (Pearson's r = 0.83, p < 0.001), case complexity (beta = 0.74, p < 0.001), level of experience (beta = -0.96, p < 0.001), and handoff accuracy (r = -0.34, p < 0.001). These results offer encouragement that intrinsic load during handoffs may be measured via a self-report measure. Additional work is required to develop an adequate measure of extraneous load.

Factor Structure of the Penn State Worry Questionnaire: Examination of a Method Factor

ERIC Educational Resources Information Center

Hazlett-Stevens, Holly; Ullman, Jodie B.; Craske, Michelle G.

2004-01-01

The Penn State Worry Questionnaire (PSWQ) was originally designed as a unifactorial measure of pathological trait worry. However, recent studies supported a two-factor solution with positively worded items loading on the first factor and reverse-scored items loading on a second factor. The current study compared this two-factor model to a negative…

A VERSATILE FAMILY OF GALACTIC WIND MODELS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bustard, Chad; Zweibel, Ellen G.; D’Onghia, Elena, E-mail: bustard@wisc.edu

2016-03-01

We present a versatile family of model galactic outflows including non-uniform mass and energy source distributions, a gravitational potential from an extended mass source, and radiative losses. The model easily produces steady-state wind solutions for a range of mass-loading factors, energy-loading factors, galaxy mass, and galaxy radius. We find that, with radiative losses included, highly mass-loaded winds must be driven at high central temperatures, whereas low mass-loaded winds can be driven at low temperatures just above the peak of the cooling curve, meaning radiative losses can drastically affect the wind solution even for low mass-loading factors. By including radiative losses,more » we are able to show that subsonic flows can be ignored as a possible mechanism for expelling mass and energy from a galaxy compared to the more efficient transonic solutions. Specifically, the transonic solutions with low mass loading and high energy loading are the most efficient. Our model also produces low-temperature, high-velocity winds that could explain the prevalence of low-temperature material in observed outflows. Finally, we show that our model, unlike the well-known Chevalier and Clegg model, can reproduce the observed linear relationship between wind X-ray luminosity and star formation rate (SFR) over a large range of SFR from 1–1000 M{sub ⊙} yr{sup −1} assuming the wind mass-loading factor is higher for low-mass, and hence, low-SFR galaxies. We also constrain the allowed mass-loading factors that can fit the observed X-ray luminosity versus SFR trend, further suggesting an inverse relationship between mass loading and SFR as explored in advanced numerical simulations.« less

LRFD Resistance Factor Calibration for Axially Loaded Drilled Shafts in the Las Vegas Valley

DOT National Transportation Integrated Search

2016-07-19

Resistance factors for LRFD of axially loaded drilled shafts in the Las Vegas Valley are calibrated using data from 41 field load tests. In addition to the traditional implementation of Monte Carlo (MC) simulations for calibration, a more robust tech...

Evaluation of LADOTD traffic load data for determination of traffic load equivalency factors.

DOT National Transportation Integrated Search

2001-07-01

This study updates Louisiana's Load Equivalency Factor (LEF) tables, which are used as an integral part of the State's highway design and rehabilitation effort. This study was required because the tables have not been updated in over 15 years and are...

Crack growth induced by thermal-mechanical loading

NASA Astrophysics Data System (ADS)

John, R.; Hartman, G. A.; Gallagher, J. P.

1992-06-01

Advanced aerospace structures are often subjected to combined thermal and mechanical loads. The fracture-mechanics behavior of the structures may be altered by the thermal state existing around the crack. Hence, design of critical structural elements requires the knowledge of stress-intensity factors under both thermal and mechanical loads. This paper describes the development of an experimental technique to verify the thermal-stress-intensity factor generated by a temperature gradient around the crack. Thin plate specimens of a model material (AISI-SAE 1095 steel) were used for the heat transfer and thermal-mechanical fracture tests. Rapid thermal loading was achieved using high-intensity focused infrared spot heaters. These heaters were also used to generate controlled temperature rates for heat-transfer verification tests. The experimental results indicate that thermal loads can generate stress-intensity factors large enough to induce crack growth. The proposed thermal-stress-intensity factors appear to have the same effect as the conventional mechanical-stress-intensity factors with respect to fracture.

Radiation pattern of a borehole radar antenna

USGS Publications Warehouse

Ellefsen, K.J.; Wright, D.L.

2005-01-01

The finite-difference time-domain method was used to simulate radar waves that were generated by a transmitting antenna inside a borehole. The simulations were of four different models that included features such as a water-filled borehole and an antenna with resistive loading. For each model, radiation patterns for the far-field region were calculated. The radiation patterns show that the amplitude of the radar wave was strongly affected by its frequency, the water-filled borehole, the resistive loading of the antenna, and the external metal parts of the antenna (e.g., the cable head and the battery pack). For the models with a water-filled borehole, their normalized radiation patterns were practically identical to the normalized radiation pattern of a finite-length electric dipole when the wavelength in the formation was significantly greater than the total length of the radiating elements of the model antenna. The minimum wavelength at which this criterion was satisfied depended upon the features of the antenna, especially its external metal parts. ?? 2005 Society of Exploration Geophysicists. All rights reserved.

Cardiorespiratory interactions during resistive load breathing.

PubMed

Calabrese, P; Perrault, H; Dinh, T P; Eberhard, A; Benchetrit, G

2000-12-01

The addition to the respiratory system of a resistive load results in breathing pattern changes and in negative intrathoracic pressure increases. The aim of this study was to use resistive load breathing as a stimulus to the cardiorespiratory interaction and to examine the extent of the changes in heart rate variability (HRV) and respiratory sinus arrhythmia (RSA) in relation to the breathing pattern changes. HRV and RSA were studied in seven healthy subjects where four resistive loads were applied in a random order during the breath and 8-min recording made in each condition. The HRV spectral power components were computed from the R-R interval sequences, and the RSA amplitude and phase were computed from the sinusoid fitting the instantaneous heart rate within each breath. Adding resistive loads resulted in 1) increasing respiratory period, 2) unchanging heart rate, and 3) increasing HRV and changing RSA characteristics. HRV and RSA characteristics are linearly correlated to the respiratory period. These modifications appear to be linked to load-induced changes in the respiratory period in each individual, because HRV and RSA characteristics are similar at a respiratory period obtained either by loading or by imposed frequency breathing. The present results are discussed with regard to the importance of the breathing cycle duration in these cardiorespiratory interactions, suggesting that these interactions may depend on the time necessary for activation and dissipation of neurotransmitters involved in RSA.

Different patterns of vein loading of exogenous ( sup 14 C)sucrose in leaves of pisum sativum and coleus blumei

DOE Office of Scientific and Technical Information (OSTI.GOV)

Turgeon, R.; Wimmers, L.E.

1988-05-01

Vein loading of exogenous ({sup 14}C)sucrose was studied using short uptake and wash periods to distinguish between direct loading into veins and loading via mesophyll tissue. Mature leaf tissue of Pisum sativum L. cv Little Marvel, or Coleus blumei Benth. cv Candidum, was abraded and leaf discs were floated on ({sup 14}C)sucrose solution for 1 or 2 minutes. Discs were then washed for 1 to 30 min either at room temperature or in the cold and were frozen, lyophilized, and autoradiographed. In P. sativum, veins were clearly labeled after 1 minute uptake and 1 minute wash periods. Autoradiographic images didmore » not change appreciably with longer times of uptake or wash. Vein loading was inhibited by p-chloromercuribenzenesulfonic acid. These results indicate that uptake of exogenous sucrose occurs directly into the veins in this species. When C. blumei leaf discs were floated on ({sup 14}C)sucrose for 2 minutes and washed in the cold, the mesophyll was labeled but little, if any, minor vein loading occurred. When discs were labeled for 2 minutes and washed at room temperature, label was transferred from the mesophyll to the veins within minutes. These results indicate that there may be different patterns of phloem loading of photosynthetically derived sucrose in these two species.« less

Utilizing an Energy Management System with Distributed Resources to Manage Critical Loads and Reduce Energy Costs

DTIC Science & Technology

2014-09-01

peak shaving, conducting power factor correction, matching critical load to most efficient distributed resource, and islanding a system during...photovoltaic arrays during islanding, and power factor correction, the implementation of the ESS by itself is likely to prove cost prohibitive. The DOD...These functions include peak shaving, conducting power factor correction, matching critical load to most efficient distributed resource, and islanding a

From Anxiety to Enthusiasm: Emotional Patterns among Student Teachers

ERIC Educational Resources Information Center

Anttila, Henrika; Pyhältö, Kirsi; Soini, Tiina; Pietarinen, Janne

2017-01-01

Studying to become a teacher is a highly emotional experience. Nevertheless, little is known about emotional patterns and emotional change. The aim of this study is to enhance the understanding of student teachers' academic emotions by exploring patterns of emotions experienced in emotionally loaded episodes. A total of 19 primary school student…

Effects of pond management on biodiversity patterns and community structure of zooplankton in urban environments.

PubMed

Suski, Jamie G; Swan, Christopher M; Salice, Christopher J; Wahl, Charles F

2018-04-01

As urban areas continue expanding, major cities become connected forming megacities. Urban encroachment into natural areas transforms the landscape into a built environment with heterogeneously distributed patches of novel habitat. Community structure within novel habitats is influenced by anthropogenic factors including fragmentation and species interactions. Alterations in complex biodiversity patterns may be used to assess how urban stressors impact community assemblages which, ultimately, may inform sustainable management decisions. To manage algal blooms, Aquashade® is applied directly to ponds. We investigated the effects of Aquashade®, nutrient loading and dispersal on local species diversity and compositional turnover of zooplankton communities from suburban ponds in Columbia, MD, USA using a mesocosm approach. We found that Aquashade® acted as an environmental filter by increasing local species diversity and decreasing compositional turnover. This ultimately could have an overall homogenizing effect on the regional species pool (or γ-diversity). The same pattern was observed in mesocosms that received simulated dispersal events of zooplankton. Nutrients, overall, increased autotrophic biomass and while Aquashade® had no effect on autotrophic biomass, the interaction of nutrients and Aquashade® similarly caused a homogenization of the zooplankton community. Additionally, there was an overall increase in cladoceran ephippia in mesocosms receiving Aquashade® compared to those not, suggesting there is a 'trigger' switching cladocerans from parthenogenic to sexual reproduction. Taken together, our results show the application of Aquashade®, nutrient loading and dispersal shift biodiversity patterns in urban zooplankton communities. We hypothesize these shifts originate at the resource level through alterations in the phytoplankton community either through composition or nutritive value in ponds receiving Aquashade®. Our study illustrates the importance of investigating multiple-scales of community assemblages when assessing impacts of anthropogenic stressors. Consideration of how to best manage green spaces may include planned un-managed areas to maintain regional biodiversity and heterogenous communities within the urban environment. Copyright © 2017. Published by Elsevier B.V.

Resistance factors for 100% dynamic testing, with and without static load tests.

DOT National Transportation Integrated Search

2011-05-01

Current department of transportation (DOT) and Federal Highway Administration (FHWA) practice has highly : variable load and resistance factor design (LRFD) resistance factors, , for driven piles from design (e.g., Standard : Penetration Tests (SPT...

The Role of Cardiovascular Risk Factors and Stroke in Familial Alzheimer Disease.

PubMed

Tosto, Giuseppe; Bird, Thomas D; Bennett, David A; Boeve, Bradley F; Brickman, Adam M; Cruchaga, Carlos; Faber, Kelley; Foroud, Tatiana M; Farlow, Martin; Goate, Alison M; Graff-Radford, Neill R; Lantigua, Rafael; Manly, Jennifer; Ottman, Ruth; Rosenberg, Roger; Schaid, Daniel J; Schupf, Nicole; Stern, Yaakov; Sweet, Robert A; Mayeux, Richard

2016-10-01

The contribution of cardiovascular disease (CV) and cerebrovascular disease to the risk for late-onset Alzheimer disease (LOAD) has been long debated. Investigations have shown that antecedent CV risk factors increase the risk for LOAD, although other investigations have failed to validate this association. To study the contribution of CV risk factors (type 2 diabetes, hypertension, and heart disease) and the history of stroke to LOAD in a data set of large families multiply affected by LOAD. The National Institute on Aging Late-Onset Alzheimer Disease/National Cell Repository for Alzheimer Disease family study (hereinafter referred to as NIA-LOAD study) is a longitudinal study of families with multiple members affected with LOAD. A multiethnic community-based longitudinal study (Washington Heights-Inwood Columbia Aging Project [WHICAP]) was used to replicate findings. The 6553 participants in the NIA-LOAD study were recruited from 23 US Alzheimer disease centers with ongoing data collection since 2003; the 5972 WHICAP participants were recruited at Columbia University with ongoing data collection since 1992. Data analysis was performed from 2003 to 2015. Generalized mixed logistic regression models tested the association of CV risk factors (primary association) with LOAD. History of stroke was used for the secondary association. A secondary model adjusted for the presence of an apolipoprotein E (APOE) ε4 allele. A genetic risk score, based on common variants associated with LOAD, was used to account for LOAD genetic risk beyond the APOE ε4 effect. Mediation analyses evaluated stroke as a mediating factor between the primary association and LOAD. A total of 6553 NIA-LOAD participants were included in the analyses (4044 women [61.7%]; 2509 men [38.3%]; mean [SD] age, 77.0 [9] years), with 5972 individuals from the WHICAP study included in the replication sample (4072 women [68.2%]; 1900 men [31.8%]; mean [SD] age, 76.5 [7.0] years). Hypertension was associated with decreased LOAD risk (odds ratio [OR], 0.63; 95% CI, 0.55-0.72); type 2 diabetes and heart disease were not. History of stroke conferred greater than 2-fold increased risk for LOAD (OR, 2.23; 95% CI, 1.75-2.83). Adjustment for APOE ε4 did not alter results. The genetic risk score was associated with LOAD (OR, 2.85; 95% CI, 2.05-3.97) but did not change the independent association of LOAD with hypertension or stroke. In the WHICAP sample, hypertension was not associated with LOAD (OR, 0.99; 95% CI, 0.88-1.11), whereas history of stroke increased the risk for LOAD (OR, 1.96; 95% CI, 1.56-2.46). The effect of hypertension on LOAD risk was also mediated by stroke in the NIA-LOAD and the WHICAP samples. In familial and sporadic LOAD, a history of stroke was significantly associated with increased disease risk and mediated the association between selected CV risk factors and LOAD, which appears to be independent of the LOAD-related genetic background.

The Role of Cardiovascular Risk Factors and Stroke in Familial Alzheimer Disease

PubMed Central

Tosto, Giuseppe; Bird, Thomas D.; Bennett, David A.; Boeve, Bradley F.; Brickman, Adam M.; Cruchaga, Carlos; Faber, Kelley; Foroud, Tatiana M.; Farlow, Martin; Goate, Alison M.; Graff-Radford, Neill R.; Lantigua, Rafael; Manly, Jennifer; Ottman, Ruth; Rosenberg, Roger; Schaid, Daniel J.; Schupf, Nicole; Stern, Yaakov; Sweet, Robert A.; Mayeux, Richard

2016-01-01

Importance The contribution of cardiovascular disease (CV) and cerebrovascular disease to the risk for late-onset Alzheimer disease (LOAD) has been long debated. Investigations have shown that antecedent CV risk factors increase the risk for LOAD, although other investigations have failed to validate this association. Objective To study the contribution of CV risk factors (type 2 diabetes, hypertension, and heart disease) and the history of stroke to LOAD in a data set of large families multiply affected by LOAD. Design, Setting, and Participants The National Institute on Aging Late-Onset Alzheimer Disease/National Cell Repository for Alzheimer Disease family study (hereinafter referred to as NIA-LOAD study) is a longitudinal study of families with multiple members affected with LOAD. A multiethnic community-based longitudinal study (Washington Heights–Inwood Columbia Aging Project [WHICAP]) was used to replicate findings. The 6553 participants in the NIA-LOAD study were recruited from 23 US Alzheimer disease centers with ongoing data collection since 2003; the 5972 WHICAP participants were recruited at Columbia University with ongoing data collection since 1992. Data analysis was performed from 2003 to 2015. Main Outcomes and Measures Generalized mixed logistic regression models tested the association of CV risk factors (primary association) with LOAD. History of stroke was used for the secondary association. A secondary model adjusted for the presence of an apolipoprotein E (APOE) ε4 allele. A genetic risk score, based on common variants associated with LOAD, was used to account for LOAD genetic risk beyond the APOE ε4 effect. Mediation analyses evaluated stroke as a mediating factor between the primary association and LOAD. Results A total of 6553 NIA-LOAD participants were included in the analyses (4044 women [61.7%]; 2509 men [38.3%]; mean [SD] age, 77.0 [9] years), with 5972 individuals from the WHICAP study included in the replication sample (4072 women [68.2%]; 1900 men [31.8%]; mean [SD] age, 76.5 [7.0] years). Hypertension was associated with decreased LOAD risk (odds ratio [OR], 0.63; 95% CI, 0.55-0.72); type 2 diabetes and heart disease were not. History of stroke conferred greater than 2-fold increased risk for LOAD (OR, 2.23; 95% CI, 1.75-2.83). Adjustment for APOE ε4 did not alter results. The genetic risk score was associated with LOAD (OR, 2.85; 95% CI, 2.05-3.97) but did not change the independent association of LOAD with hypertension or stroke. In the WHICAP sample, hypertension was not associated with LOAD (OR, 0.99; 95% CI, 0.88-1.11), whereas history of stroke increased the risk for LOAD (OR, 1.96; 95% CI, 1.56-2.46). The effect of hypertension on LOAD risk was also mediated by stroke in the NIA-LOAD and the WHICAP samples. Conclusions and Relevance In familial and sporadic LOAD, a history of stroke was significantly associated with increased disease risk and mediated the association between selected CV risk factors and LOAD, which appears to be independent of the LOAD-related genetic background. PMID:27533593

Compositional symbol grounding for motor patterns.

PubMed

Greco, Alberto; Caneva, Claudio

2010-01-01

We developed a new experimental and simulative paradigm to study the establishing of compositional grounded representations for motor patterns. Participants learned to associate non-sense arm motor patterns, performed in three different hand postures, with non-sense words. There were two group conditions: in the first (compositional), each pattern was associated with a two-word (verb-adverb) sentence; in the second (holistic), each same pattern was associated with a unique word. Two experiments were performed. In the first, motor pattern recognition and naming were tested in the two conditions. Results showed that verbal compositionality had no role in recognition and that the main source of confusability in this task came from discriminating hand postures. As the naming task resulted too difficult, some changes in the learning procedure were implemented in the second experiment. In this experiment, the compositional group achieved better results in naming motor patterns especially for patterns where hand postures discrimination was relevant. In order to ascertain the differential effect, upon this result, of memory load and of systematic grounding, neural network simulations were also made. After a basic simulation that worked as a good model of subjects performance, in following simulations the number of stimuli (motor patterns and words) was increased and the systematic association between words and patterns was disrupted, while keeping the same number of words and syntax. Results showed that in both conditions the advantage for the compositional condition significantly increased. These simulations showed that the advantage for this condition may be more related to the systematicity rather than to the mere informational gain. All results are discussed in connection to the possible support of the hypothesis of a compositional motor representation and toward a more precise explanation of the factors that make compositional representations working.

The von Mises stress distribution on the surface of UHMWPE with texture-shaped variation in the presence of normal load and dry sliding contact

NASA Astrophysics Data System (ADS)

Lestari, W. D.; Jamari, J.; Bayuseno, A. P.

2017-04-01

The texture shapes play a key role in the tribological performance of the surface material. This paper presents a study on the use of the 3D finite element method for surface stress analysis on the different texture shape under load and dry sliding contact. The five texture-shaped model was investigated in this work, namely square, circle, ellipse, triangle, and chevron. The result shown that the square shape has the highest value of von Mises resultant stress under static load. In contrast, the dry sliding contact on the triangle shape provided the highest von Mises stress distribution. The lowest value of von Mises stress can be found in the texture pattern of circle, square, and chevron under influence of load for 17 N, 30 N, and 50 N, respectively. Those texture patterns applied to surface of Ultra High Molecular Weight Polyethylene (UHMWPE) may have a strong effect on the reduction of wear rate and enhance tribological performance.

Foot Loading Characteristics of Chinese Bound Feet Women: A Comparative Analysis

PubMed Central

Gu, Yaodong; Mei, Qichang; Fernandez, Justin; Li, Jianshe; Ren, Xuejun; Feng, Neng

2015-01-01

The custom of bound feet among Chinese women has existed for almost a century. This practice has influenced the daily life of Chinese women, especially during everyday locomotion. The primary aim of this study is to analyze the loading patterns of bound feet. Specifically, the plantar pressure and center of pressure were analyzed for peak pressure, contact area, force time integral, center of pressure displacement velocity and trajectory in the anterior-posterior direction via a comparison with normal feet. The key outcomes from this work were that the forefoot and rearfoot of bound feet bear the whole loading during stance phase. The center of pressure displacement velocity of bound feet was also greatly reduced with the shortening of trajectories. This suggests that the proprioceptive system adjusts motor function to adapt to new loading patterns while maintaining locomotive stability. A biomechanical understanding of bound feet may assist with prevention, treatment and rehabilitation of bound feet disorders. PMID:25884982

Torsion sensing based on patterned piezoelectric beams

NASA Astrophysics Data System (ADS)

Cha, Youngsu; You, Hangil

2018-03-01

In this study, we investigated the sensing characteristics of piezoelectric beams under torsional loads. We used partially patterned piezoelectric beams to sense torsion. In particular, the piezoelectric patches are located symmetrically with respect to the line of the shear center of the beam. The patterned piezoelectric beam is modeled as a slender beam, and its electrical responses are obtained by piezoelectric electromechanical equations. To validate the modeling framework, experiments are performed using a setup that forces pure torsional deformation. Three different geometric configurations of the patterned piezoelectric layer are used for the experiments. The frequency and amplitude of the forced torsional load are systematically varied in order to study the behavior of the piezoelectric sensor. Experimental results demonstrate that two voltage outputs of the piezoelectric beam are approximately out of phase with identical amplitude. Moreover, the length of the piezoelectric layers has a significant influence on the sensing properties. Our theoretical predictions using the model support the experimental findings.

Nativity differences in allostatic load by age, sex, and Hispanic background from the Hispanic Community Health Study/Study of Latinos.

PubMed

Salazar, Christian R; Strizich, Garrett; Seeman, Teresa E; Isasi, Carmen R; Gallo, Linda C; Avilés-Santa, M Larissa; Cai, Jianwen; Penedo, Frank J; Arguelles, Willian; Sanders, Anne E; Lipton, Richard B; Kaplan, Robert C

2016-12-01

Allostatic load (AL), an index of biological "wear and tear" on the body from cumulative exposure to stress, has been little studied in US Hispanics/Latinos. We investigated AL accumulation patterns by age, sex, and nativity in the Hispanic Community Health Study/Study of Latinos. We studied 15,830 Hispanic/Latinos of Mexican, Cuban, Dominican, Puerto Rican, Central and South American descent aged 18-74 years, 77% of whom were foreign-born. Consistent with the conceptualization of AL, we developed an index based upon 16 physiological markers that spanned the cardiometabolic, parasympathetic, and inflammatory systems. We computed mean adjusted AL scores using log-linear models across age-groups (18-44, 45-54, 55-74 years), by sex and nativity status. Among foreign-born individuals, differences in AL by duration of residence in the US (<10, ≥10 years) and age at migration (<24, ≥24 years) were also examined. In persons younger than 55 years old, after controlling for socioeconomic and behavioral factors, AL was highest among US-born individuals, intermediate in foreign-born Hispanics/Latinos with longer duration in the US (≥10 years), and lowest among those with shorter duration in the US (<10 years) ( P <0.0001 for increasing trend). Similarly, AL increased among the foreign-born with earlier age at immigration. These trends were less pronounced among individuals ≥55 years of age. Similar patterns were observed across all Hispanic/Latino heritage groups ( P for interaction=0.5). Our findings support both a "healthy immigrant" pattern and a loss of health advantage over time among US Hispanics/Latinos of diverse heritages.

Atmospheric circulation feedback on west Asian dust and Indian monsoon rainfall

NASA Astrophysics Data System (ADS)

Kaskaoutis, Dimitris; Houssos, Elias; Gautam, Ritesh; Singh, Ramesh; Rashki, Alireza; Dumka, Umesh

2016-04-01

Classification of the atmospheric circulation patterns associated with high aerosol loading events over the Ganges valley, via the synergy of Factor and Cluster analysis techniques, has indicated six different synoptic weather patterns, two of which mostly occur during late pre-monsoon and monsoon seasons (May to September). The current study focuses on examining these two specific clusters that are associated with different mean sea level pressure (MSLP), geopotential height at 700 hPa (Z700) and wind fields that seem to affect the aerosol (mostly dust) emissions and precipitation distribution over the Indian sub-continent. Furthermore, the study reveals that enhanced aerosol presence over the Arabian Sea is positively associated with increased rainfall over the Indian landmass. The increased dust over the Arabian Sea and rainfall over India are associated with deepening of the northwestern Indian and Arabian lows that increase thermal convection and convergence of humid air masses into Indian landmass, resulting in larger monsoon precipitation. For this cluster, negative MSLP and Z700 anomalies are observed over the Arabian Peninsula that enhance the dust outflow from Arabia and, concurrently, the southwesterly air flow resulting in increase in monsoon precipitation over India. The daily precipitation over India is found to be positively correlated with the aerosol loading over the Arabian Sea for both weather clusters, thus verifying recent results from satellite observations and model simulations concerning the modulation of the Indian summer monsoon rainfall by the Arabian dust. The present work reveals that in addition to the radiative impacts of dust on modulating the monsoon rainfall, differing weather patterns favor changes in dust emissions, accumulation as well as rainfall distribution over south Asia.

Factor Analysis via Components Analysis

ERIC Educational Resources Information Center

Bentler, Peter M.; de Leeuw, Jan

2011-01-01

When the factor analysis model holds, component loadings are linear combinations of factor loadings, and vice versa. This interrelation permits us to define new optimization criteria and estimation methods for exploratory factor analysis. Although this article is primarily conceptual in nature, an illustrative example and a small simulation show…

A preliminary study to measure and develop job satisfaction scale for medical teachers.

PubMed

Bhatnagar, Kavita; Srivastava, Kalpana; Singh, Amarjit; Jadav, S L

2011-07-01

Job satisfaction of medical teachers has an impact on quality of medical education and patient care. In this background, the study was planned to develop scale and measure job satisfaction status of medical teachers. To generate items pertaining to the scale of job satisfaction, closed-ended and open-ended questionnaires were administered to medical professionals. The job satisfaction questionnaire was developed and rated on Likert type of rating scale. Both quantitative and qualitative methods were used to ascertain job satisfaction among 245 health science faculty of an autonomous educational institution. Factor loading was calculated and final items with strong factor loading were selected. Data were statistically evaluated. Average job satisfaction score was 53.97 on a scale of 1-100. The Cronbach's alpha reliability coefficient was 0.918 for entire set of items. There was statistically significant difference in job satisfaction level across different age groups (P 0.0358) showing a U-shaped pattern and fresh entrants versus reemployed faculty (P 0.0188), former showing lower satisfaction. Opportunity for self-development was biggest satisfier, followed by work, opportunity for promotion, and job security. Factors contributing toward job dissatisfaction were poor utilization of skills, poor promotional prospects, inadequate pay and allowances, work conditions, and work atmosphere. Tertiary care teaching hospitals in autonomous educational institutions need to build infrastructure and create opportunities for their medical professional. Job satisfaction of young entrants needs to be raised further by improving their work environment. This will pave the way for effective delivery of health care.

Laterally Loaded Partially Prestressed Concrete Piles

DTIC Science & Technology

1989-09-01

of an extensive test program onl laterali y ioadeu. partially pr- estressed concrete fender piles. The study Included service load range as well ats...12,000-psi design strength). Configura- tion G utilized 14 r:- estress strand, in an unsymmetric pattern. To provide a uniform concrete prestress of 540...sudden loss in load carrying capacity directly related to the loss of concrete area. The compression concrete fractured longitudinally and along the

What is the relationship between mental workload factors and cognitive load types?

PubMed

Galy, Edith; Cariou, Magali; Mélan, Claudine

2012-03-01

The present study tested the hypothesis of an additive interaction between intrinsic, extraneous and germane cognitive load, by manipulating factors of mental workload assumed to have a specific effect on either type of cognitive load. The study of cognitive load factors and their interaction is essential if we are to improve workers' wellbeing and safety at work. High cognitive load requires the individual to allocate extra resources to entering information. It is thought that this demand for extra resources may reduce processing efficiency and performance. The present study tested the effects of three factors thought to act on either cognitive load type, i.e. task difficulty, time pressure and alertness in a working memory task. Results revealed additive effects of task difficulty and time pressure, and a modulation by alertness on behavioral, subjective and psychophysiological workload measures. Mental overload can be the result of a combination of task-related components, but its occurrence may also depend on subject-related characteristics, including alertness. Solutions designed to reduce incidents and accidents at work should consider work organization in addition to task constraints in so far that both these factors may interfere with mental workload. Copyright © 2011 Elsevier B.V. All rights reserved.

Optimization of 10 kW solar photovoltaic – diesel generator hybrid energy system for different load factors at Jaisalmer location of Rajasthan, India

NASA Astrophysics Data System (ADS)

Saraswat, S. K.; Rao, K. V. S.

2018-03-01

Jaisalmer town in Rajasthan, India is having annual average solar insolation of 5.80 kWh/m2/day and 270 – 300 clear sky days in a year. A 10 kW off-grid hybrid energy system (HES) consisting of solar photovoltaic panels – diesel generator – bidirectional converter and batteries with zero percentage loss of load for Jaisalmer is designed using HOMER (version 3.4.3) software. Different system load factors of 0.33, 0.50, 0.67, 0.83 and 1 corresponding to fraction of running hours per day of the system are considered. The system is analyzed for all three aspects, namely, electrical, economic and emission point of view. Least levelized cost of electricity (LCOE) of Rs. 8.43/kWh is obtained at a load factor value of 0.5. If diesel generator alone (without Solar PV) is used to fulfil the demand for a load factor of 0.5the value of LCOE is obtained Rs.19.23/kWh. Comparison of results obtained for HES and diesel generator are made for load factor of 0.5 and 1.

The nutrient-load hypothesis: patterns of resource limitation and community structure driven by competition for nutrients and light.

PubMed

Brauer, Verena S; Stomp, Maayke; Huisman, Jef

2012-06-01

Resource competition theory predicts that the outcome of competition for two nutrients depends on the ratio at which these nutrients are supplied. Yet there is considerable debate whether nutrient ratios or absolute nutrient loads determine the species composition of phytoplankton and plant communities. Here we extend the classical resource competition model for two nutrients by including light as additional resource. Our results suggest the nutrient-load hypothesis, which predicts that nutrient ratios determine the species composition in oligotrophic environments, whereas nutrient loads are decisive in eutrophic environments. The underlying mechanism is that nutrient enrichment shifts the species interactions from competition for nutrients to competition for light, which favors the dominance of superior light competitors overshadowing all other species. Intermediate nutrient loads can generate high biodiversity through a fine-grained patchwork of two-species and three-species coexistence equilibria. Depending on the species traits, however, competition for nutrients and light may also produce multiple alternative stable states, suppressing the predictability of the species composition. The nutrient-load hypothesis offers a solution for several discrepancies between classical resource competition theory and field observations, explains why eutrophication often leads to diversity loss, and provides a simple conceptual framework for patterns of biodiversity and community structure observed in nature.