WorldWideScience

Sample records for load duration factors

  1. Calibration of Load Duration Factor kmod

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Stang, Birgitte Friis Dela; Svensson, Staffan

    and the stochastic models are formulated in accordance with the load models in the Danish structural codes, DS 409, and DS 410. three damage accumulation models are considered, namely Gerhards model, Barret & Foschi's model, and Foschi & Yao's model. The parameters in these moels are fitted using data relevant...

  2. Duration of load revisited

    DEFF Research Database (Denmark)

    Hoffmeyer, Preben; Sørensen, John Dalsgaard

    2007-01-01

    were formed. Four groups were subjected to short-term strength tests, and four groups were subjected to long-term tests. Creep and time to failure were moni-tored. Time to failure as a function of stress level was established and the reliability of stress level assessment was discussed. A significant...... mechanosorptive effect was demonstrated both in terms of increased creep and shortening of time to failure. The test results were employed for the calibration of four existing duration of load models. The effect of long-term loading was expressed as the stress level SL50 to cause failure after 50 years of loading...... and of the short-term and long-term strengths. For permanent and imposed library loads, reliability-based estimation of the load duration factor gave almost the same results as direct, deterministic calibration. Keywords: Creep, damage models, duration of load, equal rank assumption, load duration factor, matched...

  3. Reliability-Based Calibration of Load Duration Factors for Timber Structures

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Svensson, Staffan; Stang, Birgitte Friis Dela

    2005-01-01

    states and stochastic models for timber structures, load duration factors are calibrated using probabilistic methods. Load duration e.ects are estimated on basis of simulation of realizations of wind, snow and imposed loads in accordance with the load models in the Danish structural codes. Three damage...... is evaluated using representative short- and long-term limit states, and the load duration factor k mod is estimated using the probabilistic model such that equivalent reliability levels are obtained using short- and long-term design equations. Time variant reliability aspect is considered using a simple...

  4. Effect of Load Duration on Timber Structures in Denmark

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Stang, Birgitte Friis Dela; Svensson, Staffan

    2003-01-01

    . The parameters in these models are fitted by the Maximum Likelihood Method using data relevant for Danish structural timber and the statistical uncertainty is quantified. The reliability is evaluated using representative shortand long-term limit states, and the load duration factor kmod is estimated using...

  5. Duration of load effects of solid wood

    DEFF Research Database (Denmark)

    Svensson, Staffan

    Test methods for studying the effect of long-term loading on the load carrying capacity of structural wood are discussed. The impact of sampling procedures on test results is investigated and is exemplified. It is concluded from this investigation that the sampling method has a significant impact...

  6. Probabilistic representation of duration of load effects in timber structures

    DEFF Research Database (Denmark)

    Svensson, Staffan

    2011-01-01

    to be considered. These two cases are maximum load level exceeding load-carrying capacity and damage accumulation (caused by the load and its duration) leading to failure. The effect of both load intensity and load duration on the capacity of timber has been an area of large interest over the last decades...... models for the representation of damage accumulation in timber are considered. The parameters of these models are calibrated by the use of test data whereas uncertainties associated with the model formulation and limited sample size are considered. The DOL effect is usually taken into account in code...

  7. Factors Influencing Learner Permit Duration

    Directory of Open Access Journals (Sweden)

    Johnathon P. Ehsani

    2016-12-01

    Full Text Available An increasing number of countries are requiring an extended learner permit prior to independent driving. The question of when drivers begin the learner permit period, and how long they hold the permit before advancing to independent licensure has received little research attention. Licensure timing is likely to be related to “push” and “pull” factors which may encourage or inhibit the process. To examine this question, we recruited a sample of 90 novice drivers (49 females and 41 males, average age of 15.6 years soon after they obtained a learner permit and instrumented their vehicles to collect a range of driving data. Participants completed a series of surveys at recruitment related to factors that may influence licensure timing. Two distinct findings emerged from the time-to-event analysis that tested these push and pull factors in relation to licensure timing. The first can be conceptualized as teens’ motivation to drive (push, reflected in a younger age when obtaining a learner permit and extensive pre-permit driving experience. The second finding was teens’ perceptions of their parents’ knowledge of their activities (pull; a proxy for a parents’ attentiveness to their teens’ lives. Teens who reported higher levels of their parents’ knowledge of their activities took longer to advance to independent driving. These findings suggest time-to-licensure may be related to teens’ internal motivation to drive, and the ability of parents to facilitate or impede early licensure.

  8. Reliability-Based Modeling of Moisture and Load-Duration Effects

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Svensson, Staffan

    2005-01-01

    and moisture processes. Permanent and snow load sand moisture variations are considered and stochastic models are formulated in accordance with the load models in the Danish structural codes. A damage accumulation model based on fracture mechanics that accounts for both load duration and moisture effects...

  9. Load duration curve: A tool for technico-economic analysis of energy solutions

    Energy Technology Data Exchange (ETDEWEB)

    Poulin, Alain; Dostie, Michel; Fournier, Michael; Sansregret, Simon [Laboratoire des Technologies de l' Energie, Institut de Recherche d' Hydro-Quebec, 600 avenue de la Montagne, Shawinigan, Que. (Canada)

    2008-07-01

    Accuracy and relevance of energy solution analysis for a customer could be greatly improved when considering the relationship between the electric power demand and time, information which is usually not readily available. In an attempt to fill this gap, the concept of customer load duration curve (LDC) has been investigated. A six parameters relationship has proven to be able to accurately represent measured annual and monthly LDC of 332 commercial, institutional and industrial customers. Plotted against the load factor, the values of each of the six parameters are shown to be constrained within specific ranges. This characteristic has lead to the development of an algorithm for the generation of realistic synthetic LDC. This kind of algorithm can be implemented in a technico-economic model for population studies or risk management through Monte Carlo simulations. Here we present some results for the assessment of a peak shaving application in commercial and industrial markets using Monte Carlo simulations. (author)

  10. Implosion of Cylindrical Cavities via Short Duration Impulsive Loading

    Science.gov (United States)

    Huneault, Justin; Higgins, Andrew

    2014-11-01

    An apparatus has been developed to study the collapse of a cylindrical cavity in gelatin subjected to a symmetric impact-driven impulsive loading. A gas-driven annular projectile is accelerated to approximately 50 m/s, at which point it impacts a gelatin casting confined by curved steel surfaces that allow a transition from an annular geometry to a cylindrically imploding motion. The implosion is visualized by a high-speed camera through a window which forms the top confining wall of the implosion cavity. The initial size of the cavity is such that the gelatin wall is two to five times thicker than the impacting projectile. Thus, during impact the compression wave which travels towards the cavity is closely followed by a rarefaction resulting from the free surface reflection of the compression wave in the projectile. As the compression wave in the gelatin reaches the inner surface, it will also reflect as a rarefaction wave. The interaction between the rarefaction waves from the gelatin and projectile free surfaces leads to large tensile stresses resulting in the spallation of a relatively thin shell. The study focuses on the effect of impact parameters on the thickness and uniformity of the imploding shell formed by the cavitation in the imploding gelatin cylinder.

  11. Fixation duration surpasses pupil size as a measure of memory load in free viewing.

    Science.gov (United States)

    Meghanathan, Radha Nila; van Leeuwen, Cees; Nikolaev, Andrey R

    2014-01-01

    Oculomotor behavior reveals, not only the acquisition of visual information at fixation, but also the accumulation of information in memory across subsequent fixations. Two candidate measures were considered as indicators of such dynamic visual memory load: fixation duration and pupil size. While recording these measures, we displayed an arrangement of 3, 4 or 5 targets among distractors. Both occurred in various orientations. Participants searched for targets and reported whether in a subsequent display one of them had changed orientation. We determined to what extent fixation duration and pupil size indicate dynamic memory load, as a function of the number of targets fixated during the search. We found that fixation duration reflects the number of targets, both when this number is within and above the limit of working memory capacity. Pupil size reflects the number of targets only when it exceeds the capacity limit. Moreover, the duration of fixations on successive targets but not on distractors increases whereas pupil size does not. The increase in fixation duration with number of targets both within and above working memory capacity suggests that in free viewing fixation duration is sensitive to actual memory load as well as to processing load, whereas pupil size is indicative of processing load only. Two alternative models relating visual attention and working memory are considered relevant to these results. We discuss the results as supportive of a model which involves a temporary buffer in the interaction of attention and working memory.

  12. Breastfeeding duration and associated factors between 1960 and 2000

    Directory of Open Access Journals (Sweden)

    Danielle Soares de Oliveira

    Full Text Available Abstract Objective: To describe a historical series on the median duration of breastfeeding in a population of mothers whose children were born from the 1960s onwards, identifying factors associated with the interruption of breastfeeding in each decade. Methods: Data were analyzed from the Pró-Saúde Study, a longitudinal epidemiological investigation started in 1999 among technical and administrative employees of a university in the state of Rio de Janeiro. Breastfeeding duration was collected in two study phases: Phase 1 (1999, and phase 4 (2011-2012. Of these, those who had at least one child and reported the duration of breastfeeding for the first child were selected (n = 1539. To analyze the duration of breastfeeding, survival curves were constructed using the Kaplan-Meier method and the effect of covariates on the duration of breastfeeding was estimated by Cox regression model. Results: It was found that the median duration of breastfeeding was higher in the 1990s and 2000s and lower in the 1970s, compared to the 1960s. In addition, there was an association between higher income and maternal age with breastfeeding interruption, which was focused in the 1970s. Conclusion: There was shorter duration of breastfeeding in the 1970s compared to the 1960s. Increased duration and prevalence of breastfeeding from the 1970s onwards coincided with the national trend and the promotion of this practice since 1980.

  13. A comparison of methods for the assessment of postural load and duration of computer use

    NARCIS (Netherlands)

    Heinrich, J.; Blatter, B.M.; Bongers, P.M.

    2004-01-01

    Aim: To compare two different methods for assessment of postural load and duration of computer use in office workers. Methods: The study population existed of 87 computer workers. Questionnaire data about exposure were compared with exposures measured by a standardised or objective method. Measuring

  14. Duration of load behaviour of different sized straight timber beams subjected to bending in variable climate

    DEFF Research Database (Denmark)

    Hanhijärvi, A.; Galimard, P.; Hoffmeyer, Preben

    1998-01-01

    The paper is the second in a series which sums up the results of an extensive project to quantify the duration-of-load (DOL) effect on different sized timber beams in different climates. The paper deals with straight (unnotched) beams. The results of various DOL-tests of stepwise and constant ben...

  15. Factors affecting the duration of orthodontic treatment: a systematic review.

    Science.gov (United States)

    Mavreas, Dimitrios; Athanasiou, Athanasios E

    2008-08-01

    The aim of this study was to systematically investigate the literature for articles referring exclusively to the duration of orthodontic therapy and to explore the various factors that could affect this. A Medline search from 1990 to the first week of March 2005 was conducted, the Cochrane Database for Systematic Reviews was utilized, five orthodontic journals were hand searched, the abstracts of related articles were reviewed to search for any relevant studies that might have been missed, and the reference lists of the retrieved articles were hand assessed. Eligibility was determined by reading the reports identified by the search. The end result of this search provided 41 articles. Although there is a need for more conclusive research, the present review revealed several conclusions concerning the duration of orthodontic treatment: (1) there are indications that extraction treatment lasts longer than the non-extraction therapy; (2) age does not seem to play a role provided the patients are in the permanent dentition; (3) when Class II division 1 malocclusions are considered, there is evidence that the earlier the orthodontic treatment begins the longer its duration; (4) there is conflicting information regarding treatment duration within public health systems; (5) combined orthodontic-surgical treatment duration is variable and appears to be operator sensitive; (6) various factors, such as the technique employed, the skill and number of operators involved, the compliance of the patients, and the severity of the initial malocclusion, all seem to play a role; and (7) impacted maxillary canines appear to prolong treatment.

  16. Influence of loading pulse duration on dynamic load transfer in a simulated granular medium

    Science.gov (United States)

    Shukla, A.; Sadd, M. H.; Xu, Y.; Tai, Q. M.

    1993-11-01

    AN EXPERIMENTAL and numerical investigation was conducted to study the dynamic response of granular media when subjected to impact loadings with different periods or wavelengths. The granular medium was simulated by a one-dimensional assembly of circular disks arranged in a straight single chain. In the experimental study, the dynamic loading was produced using projectile impact from a gas gun onto one end of the granular assembly, and the measured wave signal was collected using strain gages. The numerical simulations were conducted using the distinct element method. It was found from the experiments and numerical simulations that input waves with a short period (τ ≈ 90 μs) will propagate in this granular medium with little waveform change under steady amplitude attenuation ; whereas longer waves (τ $̆200 μs) will propagate with significant waveform dispersion. For these longer wavelength signals, the smooth waveform will undergo separation into a series of short oscillatory signals, and this rearrangement of energy allows a portion of the transmitted signal to increase in amplitude during the initial phases of propagation. Thus the granular medium acts as a nonlinear wave guide, and local microstructure and contact nonlinearity will allow input signals of sufficiently long wavelength to excite resonant sub-units of the medium to produce this observed ringing separation. Following a modeling scheme originally proposed by NESTERENKO[J. Appl. Mech. Tech. Phys. 5,733 (1983)], a nonlinear wave equation model was developed which is related to soliton dynamics and leads to travelling wave solutions of specific wavelength found in our experimental and numerical studies.

  17. Factor structure underlying components of allostatic load.

    Directory of Open Access Journals (Sweden)

    Jeanne M McCaffery

    Full Text Available Allostatic load is a commonly used metric of health risk based on the hypothesis that recurrent exposure to environmental demands (e.g., stress engenders a progressive dysregulation of multiple physiological systems. Prominent indicators of response to environmental challenges, such as stress-related hormones, sympatho-vagal balance, or inflammatory cytokines, comprise primary allostatic mediators. Secondary mediators reflect ensuing biological alterations that accumulate over time and confer risk for clinical disease but overlap substantially with a second metric of health risk, the metabolic syndrome. Whether allostatic load mediators covary and thus warrant treatment as a unitary construct remains to be established and, in particular, the relation of allostatic load parameters to the metabolic syndrome requires elucidation. Here, we employ confirmatory factor analysis to test: 1 whether a single common factor underlies variation in physiological systems associated with allostatic load; and 2 whether allostatic load parameters continue to load on a single common factor if a second factor representing the metabolic syndrome is also modeled. Participants were 645 adults from Allegheny County, PA (30-54 years old, 82% non-Hispanic white, 52% female who were free of confounding medications. Model fitting supported a single, second-order factor underlying variance in the allostatic load components available in this study (metabolic, inflammatory and vagal measures. Further, this common factor reflecting covariation among allostatic load components persisted when a latent factor representing metabolic syndrome facets was conjointly modeled. Overall, this study provides novel evidence that the modeled allostatic load components do share common variance as hypothesized. Moreover, the common variance suggests the existence of statistical coherence above and beyond that attributable to the metabolic syndrome.

  18. Effects of Loading Duration and Short Rest Insertion on Cancellous and Cortical Bone Adaptation in the Mouse Tibia.

    Science.gov (United States)

    Yang, Haisheng; Embry, Rachel E; Main, Russell P

    2017-01-01

    The skeleton's osteogenic response to mechanical loading can be affected by loading duration and rest insertion during a series of loading events. Prior animal loading studies have shown that the cortical bone response saturates quickly and short rest insertions between load cycles can enhance cortical bone formation. However, it remains unknown how loading duration and short rest insertion affect load-induced osteogenesis in the mouse tibial compressive loading model, and particularly in cancellous bone. To address this issue, we applied cyclic loading (-9 N peak load; 4 Hz) to the tibiae of three groups of 16 week-old female C57BL/6 mice for two weeks, with a different number of continuous load cycles applied daily to each group (36, 216 and 1200). A fourth group was loaded under 216 daily load cycles with a 10 s rest insertion after every fourth cycle. We found that as few as 36 load cycles per day were able to induce osteogenic responses in both cancellous and cortical bone. Furthermore, while cortical bone area and thickness continued to increase through 1200 cycles, the incremental increase in the osteogenic response decreased as load number increased, indicating a reduced benefit of the increasing number of load cycles. In the proximal metaphyseal cancellous bone, trabecular thickness increased with load up to 216 cycles. We also found that insertion of a 10 s rest between load cycles did not improve the osteogenic response of the cortical or cancellous tissues compared to continuous loading in this model given the age and sex of the mice and the loading parameters used here. These results suggest that relatively few load cycles (e.g. 36) are sufficient to induce osteogenic responses in both cortical and cancellous bone in the mouse tibial loading model. Mechanistic studies using the mouse tibial loading model to examine bone formation and skeletal mechanobiology could be accomplished with relatively few load cycles.

  19. Spall fracture of copper under loading by shock waves with duration less 1 microsecond

    Directory of Open Access Journals (Sweden)

    Tkachenko M.I.

    2011-01-01

    Full Text Available The paper presents results of experimental researches on spall fracture of polycrystalline copper when loading by shock waves with intensity of 20–33 GPa and duration < 1 μs. It is shown that decrease of copper spall strength is observed behind SW front at SW intensity of ∼ 33 GPa (above threshold of formation of heterogeneous deformation bands. When reducing SW intensity to 27 GPa, spall strength is restored. Duration of the softened copper state does not exceed ∼ 0.5 μs. The method for spall strength evaluation is based on measurement of maximum damage in post-test samples.

  20. Anticoagulation duration in heterozygous factor V Leiden: a decision analysis.

    Science.gov (United States)

    Donovan, Anna K; Smith, Kenneth J; Ragni, Margaret V

    2013-01-01

    Current anticoagulation guidelines suggest that optimal anticoagulation duration for unprovoked venous thromboembolism is determined by an individual risk assessment, balancing risks of anticoagulation bleeding with venous thromboembolism recurrence. Among individuals heterozygous for the factor V Leiden mutation, while venous thromboembolism recurrence risk is greater, the risk for bleeding is recognized to be lower, suggesting longer duration anticoagulation could be considered. The objective of this study was to compare standard vs. lifelong anticoagulation in 20-year-old factor V Leiden heterozygotes with unprovoked venous thromboembolism. A Markov state-transition model was used, incorporating risks of major, minor, and fatal anticoagulation bleeding, bleeding and thromboembolism morbidity and mortality, and quality of life utilities. Model parameter values favoring lifelong anticoagulation in factor V Leiden heterozygotes were determined in sensitivity analyses. Outcomes were in quality-adjusted life years, discounted at 3% per year. In general population groups with odds ratios for venous thromboembolism recurrence and anticoagulation bleeding of 1.0, a short-term anticoagulation strategy gained 0.09 quality-adjusted life years more than a lifelong anticoagulation strategy. By contrast, in factor V Leiden heterozygotes, lifetime anticoagulation was favored if their relative risk of venous thromboembolism was greater than 1.07 or their relative risk for bleeding was less than 0.91. Results were relatively insensitive to individual variation in other parameter values. Lifelong anticoagulation may benefit individuals heterozygous for factor V Leiden and previous idiopathic venous thromboembolism. Studies assessing bleeding risk with anticoagulation in factor V Leiden heterozygotes and the costs of indefinite anticoagulation are needed to determine if lifelong anticoagulation is the optimal strategy. © 2013 Elsevier Ltd. All rights reserved.

  1. The frictional coefficient of the temporomandibular joint and its dependency on the magnitude and duration of joint loading.

    Science.gov (United States)

    Tanaka, E; Kawai, N; Tanaka, M; Todoh, M; van Eijden, T; Hanaoka, K; Dalla-Bona, D A; Takata, T; Tanne, K

    2004-05-01

    In synovial joints, friction between articular surfaces leads to shear stress within the cartilaginous tissue, which might result in tissue rupture and failure. Joint friction depends on synovial lubrication of the articular surfaces, which can be altered due to compressive loading. Therefore, we hypothesized that the frictional coefficient of the temporomandibular joint (TMJ) is affected by the magnitude and duration of loading. We tested this by measuring the frictional coefficient in 20 intact porcine TMJs using a pendulum-type friction tester. The mean frictional coefficient was 0.0145 (SD 0.0027) after a constant loading of 50 N during 5 sec. The frictional coefficient increased with the length of the preceding loading duration and exceeded 0.0220 (SD 0.0014) after 1 hr. Application of larger loading (80 N) resulted in significantly larger frictional coefficients. In conclusion, the frictional coefficient in the TMJ was proportional to the magnitude and duration of joint loading.

  2. Consultative Report on NPP Improving Loading Factor

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Compared with other advanced nuclear power plants about operation performance, we analyze the critical factor that have the negative impact in improving the loading factor of the nuclear power plants that belong to China Nuclear Union Company and summary the experience.

  3. Experimental study of low amplitude, long-duration mechanical loading of reactive materials

    Energy Technology Data Exchange (ETDEWEB)

    Urtiew, P A; Forbes, J W

    2000-10-03

    Studies of the low amplitude, long-duration mechanical loading of reactive materials rely very heavily on the experimental data in general and in particular on the data obtained from gauges placed within the experimental test sample to measure accurately the local changes of parameters of the investigated material. For a complete description of these changes taking place in a dynamically loaded material one would like to know both the spatial and the temporal resolution of pressure, temperature, volume, wave and mass velocity. However, temperature and volume are not easily attainable. Therefore, most of the in-situ work is limited to measurements of pressure and both wave and mass velocities. Various types of these gauges will be discussed and their records will be illustrated. Some of these gauges have limitations but are better suited for particular applications than others. These aspects will also be discussed. Main limitation of most in-situ gauges is that they are built for one-dimensional application. However, some work is being done to develop two-dimensional gauges. This work will also be briefly discussed. While these experiments are necessary to validate theoretical models of the phenomenon, they can also provide sufficient amount of data to yield complete information on material characteristics such as its equation of state (EOS), its phase change under certain loads and its sensitivity to shock loading. Processing of these data to get important information on the behavior of both reactive and non-reactive materials will also be demonstrated.

  4. Factors influencing initiation and duration of breast feeding in Ireland.

    LENUS (Irish Health Repository)

    Leahy-Warren, Patricia

    2013-03-05

    The aim of this research was to identify factors associated with mothers breast feeding and to identify, for those who breast fed, factors associated with breast feeding for as long as planned. BACKGROUND: breast-feeding rates in Ireland are amongst the lowest in Europe. Research evidence indicates that in order for mothers to be successful at breast feeding, multiplicities of supports are necessary for both initiation and duration. The nature of these supports in tandem with other influencing factors requires analysis from an Irish perspective. DESIGN: cross-sectional study involving public health nurses and mothers in Ireland. This paper presents the results of the mothers\\' evaluation. METHOD: mothers (n=1715) with children less than three years were offered a choice of completing the self-report questionnaires online or by mail. Data were analysed and reported using descriptive and inferential statistics. FINDINGS: four in every five participants breast fed their infant and two thirds of them breast fed as long as planned. The multivariate logistic regression analysis identified that third level education, being a first time mother or previously having breast fed, participating online, having more than two public health nurse visits, and having a positive infant feeding attitude were independently and statistically significantly associated with breast feeding. Among mothers who breast fed, being aged at least 35 years, participating online, having a positive infant feeding attitude and high breast-feeding self-efficacy were independently and statistically significantly associated with breast feeding for as long as planned. CONCLUSIONS: findings from this study reinforce health inequalities therefore there needs to be a renewed commitment to reducing health inequalities in relation to breast feeding. RELEVANCE TO CLINICAL PRACTICE: this study has identified factors associated with initiation and duration of breast feeding that are potentially modifiable through

  5. Effects of extreme-duration heavy load carriage on neuromuscular function and locomotion: a military-based study.

    Directory of Open Access Journals (Sweden)

    Jordane G Grenier

    Full Text Available UNLABELLED: Trekking and military missions generally consist of carrying heavy loads for extreme durations. These factors have been separately shown to be sources of neuromuscular (NM fatigue and locomotor alterations. However, the question of their combined effects remains unresolved, and addressing this issue required a representative context. PURPOSE: The aim was to investigate the effects of extreme-duration heavy load carriage on NM function and walking characteristics. METHODS: Ten experienced infantrymen performed a 21-h simulated military mission (SMM in a middle-mountain environment with equipment weighing ∼27 kg during battles and ∼43 kg during marches. NM function was evaluated for knee extensors (KE and plantar flexors (PF pre- and immediately post-SMM using isometric maximal voluntary contraction (MVC measurement, neural electrical stimulation and surface EMG. The twitch-interpolation method was used to assess central fatigue. Peripheral changes were examined by stimulating the muscle in the relaxed state. The energy cost, mechanical work and spatio-temporal pattern of walking were also evaluated pre-/post-SMM on an instrumented treadmill in three equipment conditions: Sportswear, Battle and March. RESULTS: After the SMM, MVC declined by -10.2±3.6% for KE (P<0.01 and -10.7±16.1% for PF (P = 0.06. The origin of fatigue was essentially peripheral for both muscle groups. A trend toward low-frequency fatigue was detected for KE (5.5%, P = 0.08. These moderate NM alterations were concomitant with a large increase in perceived fatigue from pre- (rating of 8.3±2.2 to post-SMM (15.9±2.1, P<0.01. The SMM-related fatigue did not alter walking energetics or mechanics, and the different equipment carried on the treadmill did not interact with this fatigue either. CONCLUSION: this study reports the first data on physiological and biomechanical consequences of extreme-duration heavy load carriage. Unexpectedly, NM function

  6. Scheduling Jobs with Maintenance Subject to Load-Dependent Duration on a Single Machine

    Directory of Open Access Journals (Sweden)

    Yawei Qi

    2015-01-01

    Full Text Available This paper investigates a scheduling problem on a single machine with maintenance, in which the starting time of the maintenance is given in advance but its duration depends on the load of the machine before the maintenance. The goal is to minimize the makespan. We formulate it as an integer programming model and show that it is NP-hard in the ordinary sense. Then, we propose an FPTAS and point out that a special case is polynomial solvable. Finally, we design fast heuristic algorithms to solve the scheduling problem. Numerical experiments are implemented to evaluate the performance of the proposed heuristic algorithms. The results show the proposed heuristic algorithms are effective.

  7. Calibration of a silver thin film gauge for short duration convective step heat load

    Indian Academy of Sciences (India)

    SHRUTIDHARA SARMA; NIRANJAN SAHOO; AYNUR UNAL

    2016-07-01

    Thin film gauges (TFGs) are a promising candidate for measuring transient heat fluxes in the applications involving very short duration of heating environment. They are basically resistance temperature detectors (RTDs) having the capability of responding in the range of few microseconds. In the present study, asilver thin film gauge (STFG) is fabricated and calibrated in-house with a view to assess the performance of STFGs in dynamic environment. Convective heat load is supplied by a hot-air gun where the heated air jet strikes the gauge and its response is obtained through voltage signal. Subsequently, the surface heat fluxes are estimated by using one dimensional heat conduction modeling. The similar experimental environment is studied to obtain the flow behavior of hot-air jet emanating into atmosphere by using numerical simulations. The selfsimilar velocities are plotted as well as the interference of outer domain into the experiment parameters has been studied. Ultimately, the surface heat fluxes obtained from various methods are compared to analyse the performance of this hand-made STFG. This study reveals the ability of STFGs to be used in practical short duration transient situations.

  8. Monitoring of Microbial Loads During Long Duration Missions as a Risk Reduction Tool

    Science.gov (United States)

    Roman, Monsi C.

    2011-01-01

    Humans have been exploring space for more than 40 years. For all those years microorganisms have accompanied, first un-manned spacecraft/cargo and later manned vessels. Microorganisms are everywhere on Earth, could easily adapt to new environments and/or can rapidly mutate to survive in very harsh conditions. Their presence in spacecraft and cargo have caused a few inconveniences over the years of humans spaceflight, ranging from crew health, life support systems challenges and material degradation. The sterilization of spacecraft that will host humans in long duration mission would be a costly operation that will not provide a long-term solution to the microbial colonization of the vessels. As soon as a human is exposed to the spacecraft, during the mission, microorganisms will start to populate the new environment. As the hum an presence in space increases in length, the risk from the microbial load, to hardware and crew will also increase. Mitigation of this risk includes several different strategies that will include minimizing the microbial load (in numbers and diversity) and monitoring. This presentation will provide a list of the risk mitigation strategies that should be implemented during ground processing, and during the mission. It will also discuss the areas that should be discussed before an effective in-flight microbial monitoring regimen is implemented. Microbial monitoring technologies will also be presented.

  9. Construction of estimated flow- and load-duration curves for Kentucky using the Water Availability Tool for Environmental Resources (WATER)

    Science.gov (United States)

    Unthank, Michael D.; Newson, Jeremy K.; Williamson, Tanja N.; Nelson, Hugh L.

    2012-01-01

    Flow- and load-duration curves were constructed from the model outputs of the U.S. Geological Survey's Water Availability Tool for Environmental Resources (WATER) application for streams in Kentucky. The WATER application was designed to access multiple geospatial datasets to generate more than 60 years of statistically based streamflow data for Kentucky. The WATER application enables a user to graphically select a site on a stream and generate an estimated hydrograph and flow-duration curve for the watershed upstream of that point. The flow-duration curves are constructed by calculating the exceedance probability of the modeled daily streamflows. User-defined water-quality criteria and (or) sampling results can be loaded into the WATER application to construct load-duration curves that are based on the modeled streamflow results. Estimates of flow and streamflow statistics were derived from TOPographically Based Hydrological MODEL (TOPMODEL) simulations in the WATER application. A modified TOPMODEL code, SDP-TOPMODEL (Sinkhole Drainage Process-TOPMODEL) was used to simulate daily mean discharges over the period of record for 5 karst and 5 non-karst watersheds in Kentucky in order to verify the calibrated model. A statistical evaluation of the model's verification simulations show that calibration criteria, established by previous WATER application reports, were met thus insuring the model's ability to provide acceptably accurate estimates of discharge at gaged and ungaged sites throughout Kentucky. Flow-duration curves are constructed in the WATER application by calculating the exceedence probability of the modeled daily flow values. The flow-duration intervals are expressed as a percentage, with zero corresponding to the highest stream discharge in the streamflow record. Load-duration curves are constructed by applying the loading equation (Load = Flow*Water-quality criterion) at each flow interval.

  10. A model for equivalent axle load factors

    OpenAIRE

    Amorim, Sara I.R.; Pais, Jorge; Vale, Aline C.; Minhoto, Manuel

    2014-01-01

    Most design methods for road pavements require the design traffic, based on the transformation of the traffic spectrum, to be calculated into a number of equivalent passages of a standard axle using the equivalent axle load factors. Generally, these factors only consider the type of axle (single, tandem or tridem), but they do not consider the type of wheel on the axles, i.e., single or dual wheel. The type of wheel has an important influence on the calculation of the design traffic. The exis...

  11. Associated risk factors and management of chronic diabetic foot ulcers exceeding 6 months’ duration

    Directory of Open Access Journals (Sweden)

    Hassan Gubara Musa

    2012-10-01

    Full Text Available Background: The management of chronic diabetic foot ulcers (DFU poses a great challenge to the treating physician and surgeon. The aim of this study was to identify the risk factors, clinical presentation, and outcomes associated with chronic DFU > 6 months’ duration. Methods: This prospective study was performed in Jabir Abu Eliz Diabetic Centre (JADC, Khartoum, Sudan. A total of 108 patients who had DFU for >6 months were included. Recorded data included patient's demographics, DFU presentation, associated comorbidities, and outcomes. DFU description included size, depth, protective sensation, perfusion, and presence of infection. Comorbidities assessed included eye impairment, renal and heart disease. All patients received necessary local wound care with sharp debridement of any concomitant necrotic and infected tissues and off-loading with appropriate shoe gear and therapeutic devices. Results: The mean age of the studied patients was 56+SD 9 years with a male to female ratio of 3:3.3. The mean duration of DFU was 18±SD 17 months (ranging from 6 to 84 months. Ulcer healing was significantly associated with off-loading, mainly the use of total contact cast (TCC (p=0.013. Non-healing ulcerations were significantly associated with longer duration of the chronic DFU > 12 months (p=0.002, smoking (p=0.000, poor glycemic control as evidenced by an elevated HbA1c (>7%, large size (mean SD 8+4 cm, increased depth (p<0.001, presence of skin callus (p<0.000, impaired limb perfusion (p=0.001, impaired protective sensation as measured by 10 g monofilament (p=0.002, neuroischemia (p=0.002, and Charcot neuroarthropathy (p=0.017. Discussion: Risk factors associated with chronic DFU of > 6 months’ duration included the presentation of an ulcer with increased size and depth, with associated skin callus and neuroischemia, in a diabetic patient with a history of smoking and increased HbA1c >7%. Off-loading mainly with the use of TCC is an effective method

  12. Effects of load and maintenance duration on the time course of information encoding and retrieval in working memory: from perceptual analysis to post-categorization processes.

    Directory of Open Access Journals (Sweden)

    Diego ePinal

    2014-04-01

    Full Text Available Working memory (WM involves three cognitive events: information encoding, maintenance and retrieval; these are supported by brain activity in a network of frontal, parietal and temporal regions. Manipulation of WM load and duration of the maintenance period can modulate this activity. Although such modulations have been widely studied using the ERP technique, a precise description of the time course of brain activity during encoding and retrieval is still required. Here, we used this technique and principal component analysis to assess the time course of brain activity during encoding and retrieval in a delayed match to sample task. We also investigated the effects of memory load and duration of the maintenance period on ERP activity. Brain activity was similar during information encoding and retrieval and comprised six temporal factors, which closely matched the latency and scalp distribution of some ERP components: P1, N1, P2, N2, P300 and a slow wave. Changes in memory load modulated task performance and yielded variations in frontal lobe activation. Moreover, the P300 amplitude was smaller in the high than in the low load condition during encoding and retrieval. Conversely, the slow wave amplitude was higher in the high than in the low load condition during encoding, and the same was true for the N2 amplitude during retrieval. Thus, during encoding, memory load appears to modulate the processing resources for context updating and post-categorization processes, and during retrieval it modulates resources for stimulus classification and context updating. Besides, despite the lack of differences in task performance related to duration of the maintenance period, larger N2 amplitude and stronger activation of the left temporal lobe after long than after short maintenance periods were found during information retrieval. Thus, results regarding the duration of maintenance period were complex, and future work is required to test the time-based decay

  13. Get In and Get Out: Assessing Stream Sediment Loading from Short Duration Forest Harvest Operations and Rapid Haul Road Decommissioning.

    Science.gov (United States)

    Corrigan, A.; Silins, U.; Stone, M.

    2016-12-01

    Best management practices (BMPs) and associated erosion control measures for mitigating sediment impacts from forestry roads and road-stream crossings are well documented. While rapid road decommissioning after forestry operations may serve to limit broader impacts on sediment production in high value headwater streams, few studies have evaluated the combined effects of accelerated harvest operations and rapid retirement of logging roads and road-stream crossings on stream sediment. The objectives of this study were to evaluate the initial impacts of these strategies on fine sediment loading and fate during a short duration harvesting operation in 3 headwater sub-catchments in the southwestern Rocky Mountains of Alberta, Canada. A multi-pronged sampling approach (ISCOs, event focused grab sampling, continuous wash load sampling, and stream bed sediment intrusion measurements) was used to measure sediment loading and deposition in streambeds upstream and downstream of road-stream bridge crossings during harvest operations (2015) and after road and bridge crossing retirement (2016). Sediment production from forestry roads was generally much lower than has been reported from other studies in similar settings. Average total suspended solids (TSS) downstream of the bridge crossings were actually lower (-3.28 g/L; -0.704 g/L) than upstream of two bridge crossings while in-stream sediment sources contributed to elevated sediment downstream of a third road-stream crossing. Minimal in stream sediment impacts from forest harvest and road-stream crossings was likely a reflection of combined factors including a) employment of erosion control BMPs to roads and bridge crossings, b) rapid decommissioning of roads and crossings to limit exposure of linear land disturbance features, and c) drier El Niño climatic conditions during the study.

  14. Loading the limb during rhythmic leg movements lengthens the duration of both flexion and extension in human infants.

    Science.gov (United States)

    Musselman, Kristin E; Yang, Jaynie F

    2007-02-01

    Sensory input is critical for adapting motor outputs to meet environmental conditions. A ubiquitous force on all terrestrial animals is gravity. It is possible that when performing rhythmic movements, animals respond to load-related feedback in the same way by prolonging the muscle activity resisting the load. We hypothesized that for rhythmic leg movements, the period (extension or flexion) experiencing the higher load will be longer and vary more strongly with cycle period. Six rhythmic movements were studied in human infants (aged 3-10 mo), each providing different degrees of load-related feedback to the legs during flexion and extension of the limb. Kicking in supine provided similar loads (inertial) during flexion and extension. Stepping on a treadmill, kicking in supine against a foot-plate, and kicking in sitting loaded the legs during extension more than flexion, whereas air-stepping and air-stepping with ankle weights did the opposite. Video, electrogoniometry, surface electromyography, and contact forces were recorded. We showed that load-related feedback could make either the duration of flexion or extension longer. Within the tasks of stepping and kicking against a plate, infants who exerted lower forces showed shorter extensor durations than those who exerted higher forces. Because older babies tend to step with greater force, we wished to rule out the contribution of age. Eight babies (>8 mo old) were studied during stepping, in which we manipulated the amount of weight-bearing. The same effect of load was seen. Hence, the degree of loading directly affects the duration of extension in an incremental way.

  15. The effects of short-term load duration on anabolic and catabolic gene expression in the rat tail intervertebral disc.

    Science.gov (United States)

    MacLean, Jeffery J; Lee, Cynthia R; Alini, Mauro; Iatridis, James C

    2005-09-01

    The goal of this study was to determine the time-dependent response of the intervertebral disc cells to in vivo dynamic compression. Forty-seven skeletally mature Wistar rats (>12 months old) were instrumented with an Ilizarov-type device spanning caudal disc 8-9. Using a load magnitude (1 MPa) and frequency (1.0 Hz) that were previously shown to significantly alter mRNA levels in the disc, the effects of 0.5 and 4 h of loading were investigated and compared to a sham group and our previous 2 h results. Annulus and nucleus tissue of loaded (c8-9) and internal control discs (c6-7 and c10-11) were separately analyzed by real-time RT-PCR for levels of mRNA coding for various anabolic (collagen-1A1, collagen-2A1, aggrecan) and catabolic (MMP-3, MMP-13, ADAMTs-4) proteins. In the annulus, mRNA levels increased for Collagen types I & II, and MMP 3 & 13 with increasing load duration. In contrast, the nucleus had the largest increases in aggrecan, ADAMTs-4, MMP-3 and MMP-13 after 2 h of loading, with aggrecan and MMP-13 mRNA levels returning to control values after 4 h of loading. Taken in context with our previous studies, we conclude that intervertebral disc cells from the nucleus and annulus have distinct responses to dynamic mechanical compression in vivo with sensitivity to compression magnitude, frequency and duration.

  16. Exercise load index and changes in body weight during long-duration confinement in an isolated environment

    Science.gov (United States)

    Kraft, Norbert O.; Lyons, Terence J.; Binder, Heidi; Inoue, Natsuhiko; Ohshima, Hiroshi; Sekiguchi, Chiharu

    2003-01-01

    PURPOSE: The objectives of this project were to investigate exercise load and body weight related to long-duration confinement in a closed environment simulating ISS flight conditions, and to evaluate subjects' motivation to continue the experiment and their adaptation to isolation. METHODS: Four Russian male subjects participated in a 240-d experiment (Group I), and four subjects (three male subjects and one female subject) from Austria, Canada, Japan, and Russia participated in a 110-d experiment (Group II). Exercise load was estimated during confinement using a modified Rating of Perceived Exertion scale. Free reports were used to determine subjects' motivation. Body weight was measured before, during, and after confinement. RESULTS: Group I achieved their lowest exercise loads during their first month of isolation; problems with adaptation to the isolation environment were also reported during this first month. Group II exercise load was significantly lower in the second month due to crewmember problems; loss of motivation could be noted from their free reports. The subject with the lowest exercise load retired from the isolation experiment earlier than scheduled. Exercise load was not correlated with prior exercise habits. Significant differences in body weight was observed between group I and II and between Russian and non-Russian subjects. One subject in Group I experienced a significant increase in his body weight. CONCLUSION: Exercise load may be a good indicator for adaptation problems and motivation changes in closed environments. Immobility, lack of space, and smoking cessation in general did not induce significant body weight changes.

  17. Fibroblast Growth Factor 23 in Long-Duration Spaceflight

    Science.gov (United States)

    Bokhari, R.; Zwart, S. R.; Fields, E.; Heer, M.; Sibonga, J.; Smith, S. M.

    2015-01-01

    Many nutritional factors influence bone, from the basics of calcium and vitamin D, to factors which influence bone through acid/base balance, including protein, sodium, and more. Fibroblast growth factor 23 (FGF23) is a recently identified factor, secreted from osteocytes, which is involved in classic (albeit complex) feedback loops controlling phosphorus homeostasis through both vitamin D and parathyroid hormone (PTH) (1, 2). As osteocytes are gravity sensing cells, it is important to determine if there are changes in FGF23 during spaceflight. In extreme cases, such as chronic kidney disease, FGF23 levels are highly elevated. FGF23 imbalances, secondary to dietary influences, may contribute to skeletal demineralization and kidney stone risk during spaceflight.

  18. The Relationship Between Duration of Breastfeeding and Maternal Factors

    OpenAIRE

    Farhad Jafari; Houriyeh Farahrooz; Zeinab Abyar; Behzad Tadayyon; Fateme Azami

    2015-01-01

    Background & Objective: Breast milk is the best food for infants and provides all nutritional needs for child health. Some studies have been done on the factors affecting breastfeeding, and partly, the role of factors such as maternal diseases and wrong recommendations are known.   Materials & Methods: This is a cross sectional study with descriptive and analytical aspects.  The sample includes 355 people from Tehran. Data were collected through questionnaires and ...

  19. Rapid visual information processing in schizophrenic patients: the impact of cognitive load and duration of stimulus presentation. A pilot study.

    Science.gov (United States)

    Cattapan-Ludewig, Katja; Hilti, Caroline C; Ludewig, Stephan; Vollenweider, Franz X; Feldon, Joram

    2005-01-01

    The inability to sustain attention has been proposed as a core deficit in schizophrenia. The Continuous Performance Task (AX-CPT) and the Rapid Visual Information Processing Task (RVP) are widely used neuropsychological tasks to measure sustained attention. The RVP displays numbers as stimuli, whereas the AX-CPT uses letters. Ten patients with chronic schizophrenia and 18 healthy control subjects were studied using four different versions of the RVP. The versions differed with regard to stimulus presentation time (600 vs. 1,200 ms) and the number of target sequences to be memorized: either one sequence (low cognitive load) or two sequences (high cognitive load). Schizophrenic patients showed a reduced number of hits only on the task version with 600 ms stimulus duration coupled with high cognitive load. The combination of high cognitive load and short stimulus duration created a critical performance breaking point for schizophrenic patients. This finding supports the hypothesis that patients have an impaired ability to coactivate different cognitive performances; thus the results favor the theory of impaired functional connectivity in schizophrenia.

  20. Load on osseointegrated fixation of a transfemoral amputee during a fall: Determination of the time and duration of descent.

    Science.gov (United States)

    Frossard, Laurent Alain

    2010-12-01

    Mitigation of fall-related injuries for populations of transfemoral amputees fitted with a socket or an osseointegrated fixation is challenging. Wearing a protective device fitted within the prosthesis might be a possible solution, provided that issues with automated fall detection and time of deployment of the protective mechanism are solved. The first objective of this study was to give some examples of the times and durations of descent during a real forward fall of a transfemoral amputee that occurred inadvertently while attending a gait measurement session to assess the load applied on the residuum. The second objective was to present five semi-automated methods of detection of the time of descent using the load data. The load was measured directly at 200 Hz using a six-channel transducer. The average time and duration of descent were 242 ± 42 ms (145-310 ms) and 619 ± 42 ms (550-715 ms), respectively. This study demonstrated that the transition between walking and falling was characterized by times of descent that occurred sequentially. The sensitivity and specificity of an automated algorithm might be improved by combining several methods of detection based on the deviation of the loads measured from their own trends and from a template previously established.

  1. A Reduction Factor for Buckling Load of Spherical Cap Shells

    Directory of Open Access Journals (Sweden)

    P.N. Khakina

    2011-12-01

    Full Text Available The classical buckling theory usually overestimates the buckling load of shells. In this study, a reduction factor is determined using geometrical parameters so as to reduce the classical buckling load to a more realistic value based on the post-buckling load. It is observed that the buckling load is directly proportional to the thickness and rise and inversely proportional to the span of the spherical cap. Finite element modeling and simulation using ABAQUS was conducted to determine the buckling behavior of a spherical cap shell subjected to different initial geometrical imperfections. The load-deflection curves drawn from the simulation formed a plateau at the post-buckling load. It is observed that as the initial geometrical imperfection is increased, the value of the initial buckling load is almost the same as the value of the post-buckling load on the plateau. The results obtained from different shells were used to derive a formula for the reduction factor.

  2. Factors associated with duration of breastfeeding in ireland: potential areas for improvement.

    LENUS (Irish Health Repository)

    Tarrant, R C

    2011-08-01

    There is a need to comprehensively examine why mothers in Ireland discontinue breastfeeding early and to explore the factors influencing duration of breastfeeding during the first 6 months postpartum. Findings from this study provide valuable direction for future strategies and interventions aimed at increasing breastfeeding duration rates in Ireland.

  3. Evaluating the Magnitude and Duration of Cold Load Pick-up on Residential Distribution Feeders Using Multi-State Load Models

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Kevin P.; Sortomme, Eric; Venkata, S. S.; Miller, Melanie T.; Ponder, Leslie

    2016-09-01

    The increased level of demand that is associated with the restoration of service after an outage, Cold Load Pick-Up (CLPU), can be significantly higher than pre-outage levels, even exceeding the normal distribution feeder peak demand. These high levels of demand can delay restoration efforts and in extreme cases damage equipment. The negative impacts of CLPU can be mitigated with strategies that restore the feeder in sections, minimizing the load current. The challenge for utilities is to manage the current level on critical equipment while minimizing the time to restore service to all customers. Accurately modeling CLPU events is the first step in developing improved restoration strategies that minimize restoration times. This paper presents a new method for evaluating the magnitude of the CLPU peak, and its duration, using multi-state load models. The use of multi-state load models allows for a more accurate representation of the end-use loads that are present on residential distribution feeders.

  4. Influence of the Pulse Duration in the Anthropomorphic Test Device (ATD) Lower-Leg Loading Mechanics

    Science.gov (United States)

    2015-08-01

    bone as shown in Fig. 2. Side View Number of Elements: 213217 Mesh Size (Floor Mat): 2.5mm Iso View Boots Hybrid III 50th ATD Right...this may lead to higher peak load in the ATD lower tibia. Therefore, several 0 1000 2000 3000 4000 5000 6000 7000 0 2.5 5 7.5 10 12.5 15 17.5 0 2 4 6

  5. Spouse correlations in cardiovascular risk factors and the effect of marriage duration.

    Science.gov (United States)

    Knuiman, M W; Divitini, M L; Bartholomew, H C; Welborn, T A

    1996-01-01

    Spouse correlations in cardiovascular risk factors were investigated using data on 2,836 spouse pairs collected in the Busselton Population Health Surveys over the period 1966-1981. The risk factors considered were systolic blood pressure, diastolic blood pressure, body mass index, triceps fatfold, cholesterol, and forced expiratory volume (1 second). Statistically significant positive correlations (p marriage duration (trend p forced expiratory volume (p = 0.16) also decreased with marriage duration, and correlations for cholesterol (p = 0.61) and triceps fatfold (p = 0.99) increased with marriage duration. These results suggest that there is spousal concordance in cardiovascular risk factors. The lack of consistent increasing trends in the correlations with marriage duration suggests that assortative mating may be a more likely explanation than the sharing of a common environment.

  6. Duration of off-loading and recurrence rate in Charcot osteo-arthropathy treated with less restrictive regimen with removable walker

    DEFF Research Database (Denmark)

    Christensen, Tomas M; Gade-Rasmussen, Birthe; Pedersen, Lis W

    2013-01-01

    Recent literature on acute diabetic Charcot osteoarthropathy (CA) reports unusually long periods of off-loading. Data suggest that this might increase the re-currence rate. Subsequently we evaluated the influence of duration of off-loading on the risk of required re-casting.......Recent literature on acute diabetic Charcot osteoarthropathy (CA) reports unusually long periods of off-loading. Data suggest that this might increase the re-currence rate. Subsequently we evaluated the influence of duration of off-loading on the risk of required re-casting....

  7. Testing for time-varying loadings in dynamic factor models

    DEFF Research Database (Denmark)

    Mikkelsen, Jakob Guldbæk

    factors. The squared correlation coefficient times the sample size has a limiting chi-squared distribution. The test can be made robust to serial correlation in the idiosyncratic errors. We find evidence for factor loadings variance in over half of the variables in a dataset for the US economy, while...... there is evidence of time-varying loadings on the risk factors underlying portfolio returns for around 80% of the portfolios....

  8. Oxygen Uptake Responses to Submaximal Exercise Loads Do Not Change During Long-Duration Space Flight

    Science.gov (United States)

    Moore, Alan D., Jr.; Evetts, Simon N.; Feiveson, Alan H.; Lee, S. M. C.; McCleary, Frank A.; Platts, Steven H.; Ploutz-Snyder, Lori

    2011-01-01

    In previous publications we have reported that the heart rate (HR) responses to graded submaximal exercise tests are elevated during long-duration International Space Station (ISS) flights. Furthermore, the elevation in HR appears greater earlier, rather than later, during the missions. A potential confounder in the interpretation of HR results from graded exercise tests on ISS is that the cycle ergometer used (CEVIS) is vibration-isolated from the station structure. This feature causes the CEVIS assembly to sway slightly during its use and debriefing comments by some crewmembers indicate that there is a "learning curve" associated with CEVIS use. Therefore, one could not exclude the possibility that the elevated HRs experienced in the early stages of ISS missions were related to a lowered metabolic efficiency of CEVIS exercise that would raise the submaximal oxygen uptake (VO2) associated with graded exercise testing work rates.

  9. An alternative method for centrifugal compressor loading factor modelling

    Science.gov (United States)

    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.

  10. Data Mining Activity for Bone Discipline: Calculating a Factor of Risk for Hip Fracture in Long-Duration Astronauts

    Science.gov (United States)

    Ellman, R.; Sibonga, J. D.; Bouxsein, M. L.

    2010-01-01

    The factor-of-risk (Phi), defined as the ratio of applied load to bone strength, is a biomechanical approach to hip fracture risk assessment that may be used to identify subjects who are at increased risk for fracture. The purpose of this project was to calculate the factor of risk in long duration astronauts after return from a mission on the International Space Station (ISS), which is typically 6 months in duration. The load applied to the hip was calculated for a sideways fall from standing height based on the individual height and weight of the astronauts. The soft tissue thickness overlying the greater trochanter was measured from the DXA whole body scans and used to estimate attenuation of the impact force provided by soft tissues overlying the hip. Femoral strength was estimated from femoral areal bone mineral density (aBMD) measurements by dual-energy x-ray absorptiometry (DXA), which were performed between 5-32 days of landing. All long-duration NASA astronauts from Expedition 1 to 18 were included in this study, where repeat flyers were treated as separate subjects. Male astronauts (n=20) had a significantly higher factor of risk for hip fracture Phi than females (n=5), with preflight values of 0.83+/-0.11 and 0.36+/-0.07, respectively, but there was no significant difference between preflight and postflight Phi (Figure 1). Femoral aBMD measurements were not found to be significantly different between men and women. Three men and no women exceeded the theoretical fracture threshold of Phi=1 immediately postflight, indicating that they would likely suffer a hip fracture if they were to experience a sideways fall with impact to the greater trochanter. These data suggest that male astronauts may be at greater risk for hip fracture than women following spaceflight, primarily due to relatively less soft tissue thickness and subsequently greater impact force.

  11. Voltage-Sensitive Load Controllers for Voltage Regulation and Increased Load Factor in Distribution Systems

    DEFF Research Database (Denmark)

    Douglass, Philip James; Garcia-Valle, Rodrigo; Østergaard, Jacob

    2014-01-01

    consumption which can be mapped to temperature setpoint offsets of thermostat controlled loads. In networks where a lower voltage level corresponds to high system load (and vice versa), this controller acts to regulate voltage and increase the load factor. Simulations are conducted on low- and medium-voltage......This paper presents a novel controller design for controlling appliances based on local measurements of voltage. The controller finds the normalized voltage deviation accounting for the sensitivity of voltage measurements to appliance state. The controller produces a signal indicating desired power...... distribution systems with residential loads including voltage-sensitive water heaters. In low-voltage systems, the results of the simulations show the controller to be effective at reducing the extremes of voltage and increasing the load factor while respecting end-use temperature constraints. In medium-voltage...

  12. Factors associated to duration of hepatitis a outbreaks: implications for control.

    Directory of Open Access Journals (Sweden)

    Nuria Torner

    Full Text Available Even though hepatitis A mass vaccination effectiveness is high, outbreaks continue to occur. The aim of this study was to investigate the association between duration and characteristics of hepatitis A outbreaks. Hepatitis A (HA outbreaks reported between 1991 and 2007 were studied. An outbreak was defined as ≥2 epidemiologically-linked cases with ≥1 case laboratory-confirmed by detection of HA immunoglobulin M (IgM antibodies. Relationships between explanatory variables and outbreak duration were assessed by logistic regression. During the study period, 268 outbreaks (rate 2.45 per million persons-year and 1396 cases (rate 1.28 per 10(5 persons-year were reported. Factors associated with shorter duration were time to intervention (OR = 0.96; 95% CI: 0.94-0.98 and school setting (OR = 0.39; 95% CI: 0.16-0.92. In person-to-person transmission outbreaks only time to intervention was associated with shorter outbreak duration (OR = 0.96; 95% CI: 0.95-0.98. The only variables associated with shorter outbreak duration were early administration of IG or vaccine and a school setting. Timely reporting HA outbreaks was associated with outbreak duration. Making confirmed HA infections statutory reportable for clinical laboratories could diminish outbreak duration.

  13. Factors Associated to Duration of Hepatitis A Outbreaks: Implications for Control

    Science.gov (United States)

    Torner, Nuria; Broner, Sonia; Martinez, Ana; Tortajada, Cecilia; Garcia de Olalla, Patricia; Barrabeig, Irene; Sala, MariaRosa; Camps, Neus; Minguell, Sofia; Alvarez, Josep; Ferrús, Gloria; Torra, Roser; Godoy, Pere; Dominguez, Angela

    2012-01-01

    Even though hepatitis A mass vaccination effectiveness is high, outbreaks continue to occur. The aim of this study was to investigate the association between duration and characteristics of hepatitis A outbreaks. Hepatitis A (HA) outbreaks reported between 1991 and 2007 were studied. An outbreak was defined as ≥2 epidemiologically-linked cases with ≥1 case laboratory-confirmed by detection of HA immunoglobulin M (IgM) antibodies. Relationships between explanatory variables and outbreak duration were assessed by logistic regression. During the study period, 268 outbreaks (rate 2.45 per million persons-year) and 1396 cases (rate 1.28 per 105 persons-year) were reported. Factors associated with shorter duration were time to intervention (OR = 0.96; 95% CI: 0.94–0.98) and school setting (OR = 0.39; 95% CI: 0.16–0.92). In person-to-person transmission outbreaks only time to intervention was associated with shorter outbreak duration (OR = 0.96; 95% CI: 0.95–0.98). The only variables associated with shorter outbreak duration were early administration of IG or vaccine and a school setting. Timely reporting HA outbreaks was associated with outbreak duration. Making confirmed HA infections statutory reportable for clinical laboratories could diminish outbreak duration. PMID:22355358

  14. Factors influencing the microwave pulse duration in a klystron-like relativistic backward wave oscillator

    Energy Technology Data Exchange (ETDEWEB)

    Xiao Renzhen; Zhang Xiaowei; Zhang Ligang; Li Xiaoze; Zhang Lijun [National Key Laboratory of Science and Technology on High Power Microwave, Northwest Institute of Nuclear Technology, Xi' an 710024 (China)

    2012-07-15

    In this paper, we analyze the factors that affect the microwave pulse duration in a klystron-like relativistic backward wave oscillator (RBWO), including the diode voltage, the guiding magnetic field, the electron beam collector, the extraction cavity, and the gap between the electron beam and the slow wave structure (SWS). The results show that the microwave pulse duration increases with the diode voltage until breakdown occurs on the surface of the extraction cavity. The pulse duration at low guiding magnetic field is generally 5-10 ns smaller than that at high magnetic field due to the asymmetric electron emission and the larger energy spread of the electron beam. The electron beam collector can affect the microwave pulse duration significantly because of the anode plasma generated by bombardment of the electron beam on the collector surface. The introduction of the extraction cavity only slightly changes the pulse duration. The decrease of the gap between the electron beam and the SWS can increase the microwave pulse duration greatly.

  15. Prognostic factors for disability claim duration due to musculoskeletal symptoms among self-employed persons

    Directory of Open Access Journals (Sweden)

    Richter JM

    2011-12-01

    Full Text Available Abstract Background Employees and self-employed persons have, among others, different personal characteristics and different working conditions, which may influence the prognosis of sick leave and the duration of a disability claim. The purpose of the current study is to identify prognostic factors for the duration of a disability claim due to non-specific musculoskeletal disorders (MSD among self-employed persons in the Netherlands. Methods The study population consisted of 276 self-employed persons, who all had a disability claim episode due to MSD with at least 75% work disability. The study was a cohort study with a follow-up period of 12 months. At baseline, participants filled in a questionnaire with possible individual, work-related and disease-related prognostic factors. Results The following prognostic factors significantly increased claim duration: age > 40 years (Hazard Ratio 0.54, no similar symptoms in the past (HR 0.46, having long-lasting symptoms of more than six months (HR 0.60, self-predicted return to work within more than one month or never (HR 0.24 and job dissatisfaction (HR 0.54. Conclusions The prognostic factors we found indicate that for self-employed persons, the duration of a disability claim not only depends on the (history of impairment of the insured, but also on age, self-predicted return to work and job satisfaction.

  16. Estimation of The Scale Factor For Short Observing Session Duration In GNSS Positioning

    Science.gov (United States)

    Hasan Dogan, Ali; Erdogan, Bahattin

    2017-04-01

    In recent years, users prefer Global Navigation Satellite System (GNSS) technique rather than traditional techniques for geodetic applications. Accuracy of GNNS observations depends on several parameters such as surveying method, data processing strategy and software. GNSS observations are generally processed by using academic software or commercial software. Commercial software can provide solution up to 20-25 km baseline length. Moreover, academic software is preferred for scientific researches as monitoring of the movements of manmade structures or plate tectonic that are required high accurate point positioning. However, academic software gives optimistic results in terms of positioning accuracy. This situation causes wrong interpretations for important decision in deformation analysis. Therefore, the variance-covariance (VCV) matrices that are obtained from academic software should be scaled. In this study, the estimation of the scaling factor was carried out for short observing session duration in GNSS positioning. Baselines whose lengths ranging from 8 km to 268 km and session durations between 60 min and 180 min were processed using Bernese v5.2 with single baseline strategy. According to initial results, a significant dependence based on baseline lengths cannot be determined. Moreover, the results show that scaling factor changes depending on the session duration. Keywords: Relative Positioning, Short Observing Session Duration, Scale Factor, Bernese

  17. Calibration of LRFD Format for Steel Jacket Offshore Platform in China Offshore Area (2): Load, Resistance and Load Combination Factors

    Institute of Scientific and Technical Information of China (English)

    ZHOU Dao-cheng; DUAN Zhong-dong; OU Jin-ping

    2006-01-01

    Adopting the load and resistance factor design format, the design method for steel jacket platform structures is developed. Firstly, the limit state equations and design format for steel jacket platform structures are introduced. Then, the ratio of live load effect to dead load effect is estimated. The target reliabilities for design of offshore structures in China offshore area are calibrated by past practice in API RP2A-WSD code. The load and resistance factors are optimized by minimizing the difference within the target reliability and the resulting reliability over the range of load effect ratios. Considering the concurrence of different loads, load combination factors are obtained through an optimization process, and the relation between the load combination factor and load correlation coefficient is established. Finally, the design formulae for steel jacket structures in China offshore area are recommended.

  18. Epidemiology, risk factors, and consequences of obstructive sleep apnea and short sleep duration.

    Science.gov (United States)

    Al Lawati, Nabil M; Patel, Sanjay R; Ayas, Najib T

    2009-01-01

    We will review the epidemiology, risk factors, and consequences of obstructive sleep apnea (OSA) and short/long sleep duration. Obstructive sleep apnea is a disease characterized by recurrent upper airway obstruction during sleep. Obstructive sleep apnea is common, with moderate to severe disease present in approximately 9% of middle aged men and 4% of women. The prevalence of OSA in certain patient populations (such as elderly patients, hypertensive patients, patients with coronary disease, and prebariatric surgery patients) is even greater. There are a number or risk factors for disease including obesity, male sex, and family history. Obstructive sleep apnea negatively impacts quality of life and is also associated with a number of adverse safety and health consequences including cardiovascular disease and motor vehicle crashes. Short habitual sleep duration can result in excessive daytime sleepiness and reduced neurocognitive function. Sleep loss may have long-term health consequences and may lead to premature death, cardiovascular disease, and the development of diabetes.

  19. Risk factors for extended duration of acute diarrhea in young children.

    Science.gov (United States)

    Strand, Tor A; Sharma, Pushpa R; Gjessing, Håkon K; Ulak, Manjeswori; Chandyo, Ram K; Adhikari, Ramesh K; Sommerfelt, Halvor

    2012-01-01

    We sought to identify predictors of extended duration of diarrhea in young children, which contributes substantially to the nearly 1 1/2 million annual diarrheal deaths globally. We followed 6-35 month old Nepalese children enrolled in the placebo-arm of a randomized controlled trial with 391 episodes of acute diarrhea from the day they were diagnosed until cessation of the episode. Using multiple logistic regression analysis, we identified independent risk factors for having diarrhea for more than 7 days after diagnosis. Infants had a 17 (95% CI 3.5, 83)-fold and toddlers (12 to 23 month olds) a 9.9 (95% CI 2.1, 47)-fold higher odds of having such illness duration compared to the older children. Not being breastfed was associated with a 9.3 (95% CI 2.4, 35.7)-fold increase in the odds for this outcome. The odds also increased with increasing stool frequency. Furthermore, having diarrhea in the monsoon season also increased the risk of prolonged illness. We found that high stool frequency, not being breastfed, young age and acquiring diarrhea in the rainy season were risk factors for prolonged diarrhea. In populations such as ours, breastfeeding may be the most important modifiable risk factor for extended duration of diarrhea.

  20. Risk factors for extended duration of acute diarrhea in young children.

    Directory of Open Access Journals (Sweden)

    Tor A Strand

    Full Text Available OBJECTIVE AND BACKGROUND: We sought to identify predictors of extended duration of diarrhea in young children, which contributes substantially to the nearly 1 1/2 million annual diarrheal deaths globally. METHODS: We followed 6-35 month old Nepalese children enrolled in the placebo-arm of a randomized controlled trial with 391 episodes of acute diarrhea from the day they were diagnosed until cessation of the episode. Using multiple logistic regression analysis, we identified independent risk factors for having diarrhea for more than 7 days after diagnosis. RESULTS: Infants had a 17 (95% CI 3.5, 83-fold and toddlers (12 to 23 month olds a 9.9 (95% CI 2.1, 47-fold higher odds of having such illness duration compared to the older children. Not being breastfed was associated with a 9.3 (95% CI 2.4, 35.7-fold increase in the odds for this outcome. The odds also increased with increasing stool frequency. Furthermore, having diarrhea in the monsoon season also increased the risk of prolonged illness. CONCLUSION: We found that high stool frequency, not being breastfed, young age and acquiring diarrhea in the rainy season were risk factors for prolonged diarrhea. In populations such as ours, breastfeeding may be the most important modifiable risk factor for extended duration of diarrhea.

  1. Cyclodissipativity and Power Factor Improvement for Full Nonlinear Loads

    NARCIS (Netherlands)

    Puerto-Flores, Dunstano del; Ortega, Romeo; Scherpen, Jacquelien M.A.; Edelmayer, András

    2010-01-01

    In recent research, a cyclodissipativity characterization of the problem of power factor compensation (PFC) for nonlinear loads with non-sinusoidal source voltage has been presented. Using this characterization the classical capacitor and inductor compensators can be interpreted in terms of energy e

  2. Short sleep duration and large variability in sleep duration are independently associated with dietary risk factors for obesity in Danish school children

    DEFF Research Database (Denmark)

    Kjeldsen, J S; Hjorth, M F; Andersen, Rikke

    2014-01-01

    -to-day variability) as well as parent-reported sleep problems are independently associated with proposed dietary risk factors for overweight and obesity in 8-11 year old children.Design:In this cross-sectional study data on sleep duration and day-to-day variability in sleep duration were measured in 676 Danish...... and ghrelin levels.Results:Sleep duration (hours/night) was negatively and significantly (P0.003) associated with energy density (ED) of the diet (β=-0.32 kJ/g), added sugar (β=-1.50 E%) and SSB (β=-1.07 E%). Furthermore, variability in sleep duration (min/night) was positively associated with SSB (β=0.20 E...... and ethnicity).Conclusion:Our study suggests that short sleep duration, high sleep duration variability, and experiencing sleep problems are all associated with a poor, obesity-promoting diet in children.International Journal of Obesity accepted article preview online, 8 August 2013. doi:10.1038/ijo.2013.147....

  3. Varactor Modelling for Power Factor Correction in a Varying Load

    Directory of Open Access Journals (Sweden)

    Agwu D. D.

    2016-06-01

    Full Text Available : For efficient system operation, it is desirable to keep the power factor at, or very close to unity. One of the very often used methods is application of suitable power factor correction technology. Capacitors are good candidate for constant load power factor correction due to suitability and cost effectiveness. However for varying loads, synchronous condensers are preferred despite having high initial cost as a result of their being able to supply varying leading or lagging reactive power; according to their field excitation. Due to the high acquisition and operation cost of synchronous condensers, this paper presents varactors as a possible alternative for power factor correction. These are diodes that vary their capacitances and leading reactive power according to supply voltage. Applying this involves looking at variation of power factor with supply voltage; and the option of aggregating and harnessing the junction capacitance of varactors for power factor correction of varying loads at low voltage AC levels. This innovation may lead to great improvement in distribution systems requiring quality power supply

  4. Association Between Short Sleep Duration and Risk Behavior Factors in Middle School Students.

    Science.gov (United States)

    Owens, Judith; Wang, Guanghai; Lewin, Daniel; Skora, Elizabeth; Baylor, Allison

    2017-01-01

    To examine the association between self-reported sleep duration (SD) and peer/individual factors predictive of risky behaviors (risk behavior factors) in a large socioeconomically diverse school-based sample of early adolescents. Survey data collected from 10718 and 11240 eighth-grade students in 2010 and 2012, respectively, were analyzed. N/A. Self-reported school night SD was grouped as ≤4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, and ≥10 hours. Scores on 10 peer/individual risk behavior factor scales were dichotomized according to national eigth-grade cut points. The percentage of students reporting an "optimal" SD of 9 hours was 14.8% and 15.6% in 2010 and 2012, respectively; 45.6% and 46.1% reported sleep compared to an SD of 9 hours. For example, ORs for students sleeping sleep; in particular, an SD <7 hours is associated with increased risk behavior factors.

  5. Short Duration Bioastronautics Investigation 1904: Human Factors Assessment of Vibration Effects on Visual Performance during Launch

    Science.gov (United States)

    Thompson, Shelby; Holden, Kritina; Ebert, Douglas; Root, Phillip; Adelstein, Bernard; Jones, Jeffery

    2009-01-01

    The primary objective of the Short Duration Bioastronautics Investigation (SDBI) 1904 was to determine visual performance limits during Shuttle operational vibration and g-loads, specifically through the determination of minimal usable font sizes using Orion-type display formats. Currently there is little to no data available to quantify human visual performance under the extreme g- and vibration conditions of launch. Existing data on shuttle vibration magnitude and frequency is incomplete and does not address human visual performance. There have been anecdotal reports of performance decrements from shuttle crews, but no structured data have been collected. Previous work by NASA on the effects of vibration and linear g-loads on human performance was conducted during the Gemini era, but these experiments were performed using displays and controls that are dramatically different than current concepts being considered by the Constellation Program. Recently, three investigations of visual performance under vibration have been completed at NASA Ames Research Center: the first examining whole-body vibration, the second employing whole-body vibration coupled with a sustained g-load, and a third examining the effects of peak versus extended duration vibration. However, all of these studies were conducted using only a single x-axis direction (eyeballs in/out). Estimates of thrust oscillations from the Constellation Ares-I first stage are driving the need for realistic human performance requirements. SDBI 1904 was an opportunity to address the need for requirements by conducting a highly focused and applied evaluation in a relevant spaceflight environment. The SDBI was a companion effort to Detailed Test Objective (DTO) 695, which measured shuttle seat accelerations (vibration) during ascent. Data from the SDBI will serve an important role in interpreting the DTO vibration data. Both SDBI 1904 and DTO 695 were low impact with respect to flight resources, and combined, they

  6. Risk factors for predicting diarrheal duration and morbidity in children with acute diarrhea.

    Science.gov (United States)

    Patel, Archana B; Ovung, Ronithung; Badhoniya, Neetu B; Dibley, Michael J

    2012-04-01

    To identify baseline risk factors for prolonged diarrheal duration and subsequent complications in children aged 6 to 59 mo with acute diarrhea who participated in a micronutrient clinical trial in a tertiary care hospital. The adjusted odds ratio or incidence risk ratios (IRR) of the baseline variables for prolongation of diarrheal duration (cox proportional hazard model), diarrhea >7 d (multiple logistic regressions), severe dehydration experienced after hospitalization (poisson regression models) was estimated. Fever (OR 1.10, 95% CI 1.02-1.19, p = 0.02), dehydration (OR 1.32, 95% CI 1.10-1.59, p = 0.003), dysentery (OR 1.41 95% CI 1.09-1.82, p = 0.008), those who received medications (OR 1.19, 95% CI 1.03-1.39, p = 0.02), and weight for age Z-score ≤2 (OR 1.25, 95% CI 1.07-1.46, p = 0.004) were at a greater risk of prolonged diarrhea. Diarrhea >7 d was associated with younger age (OR 1.08, 95% CI 1.03-1.14, p = 0.003), female child (OR 2.33, 95% CI 1.19-4.55, p = 0.013), diarrheal duration before enrolment (OR 1.06, 95% CI 1.04-1.09, p risk factors for diarrheal morbidity prospectively. The present study showed that children of acute diarrhea with above risk factors need stricter monitoring for complications to reduce diarrheal mortality.

  7. Diabetic retinopathy, duration of diabetes and risk factors of atherosclerotic cardiovascular disease.

    Science.gov (United States)

    Job, D; Eschwège, E; Tchobroutsky, G; Guyot-Argenton, C; Aubry, J P; Dérot, N

    1975-01-01

    The present study, concerning 145 insulin-dependent diabetics showed positive relationships between the severity of retinal disease on the one hand, and body weight, blood pressure, and serum cholesterol level on the other. These relationships remain significant when the duration of the clinical diabetes and the age of the patient are taken into account. Two interpretations are suggested. They are not incompatible. In diabetic subjects, either the increase in blood pressure and serum cholesterol level causes an aggravation of diabetic retinopathy or there exists a common factor at the origin of retinal lesions and of an increase in risk of cardiovascular disease through atherosclerosis.

  8. Determination of stress intensity factors in ultrasonic fatigue loading

    Institute of Scientific and Technical Information of China (English)

    倪金刚; 张学仁; 聂景旭

    1996-01-01

    The application of displacement and energy approaches to the determination of stress intensity factors in ultrasonic fatigue crack growth (fcg) studies is discussed.The particular advantages as well as the limitations of the two approaches are evaluated.Two types of ultrasonic fatigue loading with different stress ratios are exerted on the specimen respectively: the ultrasonic fatigue loading with a stress ratio R=-1 and the ultrasonic fatigue excitations superposed upon a static mean stress with R>-1 From comparison the conclusion is formed that the energy approach developed in the investigation is more accurate,concise and suitable than commonly adopted approaches and/or formulas proposed.Experimental fcg data on a titanium alloy Ti-6Al-4V and the characteristic mechanism of the ultrasonic fcg are investigated.

  9. Factors affecting duration of the expulsive stage of parturition and piglet birth intervals in sows with uncomplicated, spontaneous farrowings.

    Science.gov (United States)

    van Dijk, A J; van Rens, B T T M; van der Lende, T; Taverne, M A M

    2005-10-15

    Modern pig farming is still confronted with high perinatal piglet losses which are mainly contributed to factors associated with the progress of piglet expulsion. Therefore the aim of this study was to identify sow- and piglet factors affecting the duration of the expulsive stage of farrowing and piglet birth intervals in spontaneous farrowing sows originating from five different breeds. In total 211 litters were investigated. Breed affected duration of the expulsive stage significantly: the shortest duration was found in Large White x Meishan F2 crossbred litters and the longest duration in Dutch Landrace litters. No effect of parity on the duration of the expulsive stage was found. An increase in littersize (Pgestation length (Ppigs.

  10. Exploration of Habitability Factors Influencing Short Duration Spaceflight: Structured Postflight Interviews of Shuttle Crewmembers

    Science.gov (United States)

    Locke, James; Leveton, Lauren; Keeton, Kathryn; Whitmire, Alexandra

    2009-01-01

    Astronauts report significant difficulties with sleep during Space missions. Psychological, physiological, and habitability factors are all thought to play a role in spaceflight insomnia. Crewmembers gain experience with the spaceflight sleep environment as their missions progress, but this knowledge is not formally collected and communicated to subsequent crews. This lack of information transfer prevents crews from optimizing their capability to sleep during mission, which leads to fatigue and its potentially deleterious effects. The goal of this project is astronauts with recent spaceflight experience to gather their knowledge of and insights into sleep in Space. Structured interviews consisting of standardized closed and open-ended questionnaires are administered to astronauts who have flown on the Space Shuttle since the Columbia disaster. It is hoped that review and analysis of the pooled responses to the interview questions will lead to greater understanding of the sleep environment during short duration spaceflight, with attention placed on problem aspects and their potential solutions.

  11. Factors affecting duration of the expulsive stage of parturition and piglet birth intervals in sows with uncomplicated, spontaneous farrowings

    NARCIS (Netherlands)

    Dijk, van A.D.J.; Rens, van B.T.T.M.; Lende, van der T.; Taverne, M.A.M.

    2005-01-01

    Modern pig farming is still confronted with high perinatal piglet losses which are mainly contributed to factors associated with the progress of piglet expulsion. Therefore the aim of this study was to identify sow- and piglet factors affecting the duration of the expulsive stage of farrowing and pi

  12. A prospective study of prognostic factors for duration of sick leave after endoscopic carpal tunnel release

    Directory of Open Access Journals (Sweden)

    Dalsgaard Jesper

    2009-11-01

    Full Text Available Abstract Background Endoscopic carpal tunnel release with a single portal technique has been shown to reduce sick leave compared to open carpal tunnel release, claiming to be a less invasive procedure and reducing scar tenderness leading to a more rapid return to work, and the purpose of this study was to identify prognostic factors for prolonged sick leave after endoscopic carpal tunnel release in a group of employed Danish patients. Methods The design was a prospective study including 75 employed patients with carpal tunnel syndrome operated with ECTR at two hospitals. The mean age was 46 years (SD 10.1, the male/female ratio was 0.42, and the mean preoperative duration of symptoms 10 months (range 6-12. Only 21 (28% were unable to work preoperatively and mean sick leave was 4 weeks (range 1-4. At base-line and at the 3-month follow-up, a self-administered questionnaire was collected concerning physical, psychological, and social circumstances in relation to the hand problem. Data from a nerve conduction examination were collected at baseline and at the 3-month follow-up. Significant prognostic factors were identified through multiple logistic regression analysis. Results After the operation, the mean functional score was reduced from 2.3 to 1.4 (SD 0.8 and the mean symptom score from 2.9 to 1.5 (SD 0.7. The mean sick leave from work after the operation was 19.8 days (SD 14.3. Eighteen patients (24% had more than 21 days of sick leave. Two patients (3% were still unable to work after 3 months. Significant prognostic factors in the multivariate analysis for more than 21 days of postoperative sick leave were preoperative sick leave, blaming oneself for the hand problem and a preoperative distal motor latency. Conclusion Preoperative sick leave, blaming oneself for the hand problem, and a preoperative distal nerve conduction motor latency were prognostic factors for postoperative work absence of more than 21 days. Other factors may be important

  13. The use of simulated rainfall to study the discharge process and the influence factors of urban surface runoff pollution loads.

    Science.gov (United States)

    Qinqin, Li; Qiao, Chen; Jiancai, Deng; Weiping, Hu

    2015-01-01

    An understanding of the characteristics of pollutants on impervious surfaces is essential to estimate pollution loads and to design methods to minimize the impacts of pollutants on the environment. In this study, simulated rainfall equipment was constructed to investigate the pollutant discharge process and the influence factors of urban surface runoff (USR). The results indicated that concentrations of total suspended solids (TSS), total nitrogen (TN), total phosphorus (TP) and chemical oxygen demand (COD) appeared to be higher in the early period and then decreased gradually with rainfall duration until finally stabilized. The capacity and particle size of surface dust, rainfall intensity and urban surface slopes affected runoff pollution loads to a variable extent. The loads of TP, TN and COD showed a positive relationship with the surface dust capacity, whereas the maximum TSS load appeared when the surface dust was 0.0317 g·cm⁻². Smaller particle sizes (rainfall intensity and surface slope enhanced the pollution carrying capacity of runoff, leading to higher pollution loads. Knowledge of the influence factors could assist in the management of USR pollution loads.

  14. Searching for a two-factor model of marriage duration: commentary on Gottman and Levenson.

    Science.gov (United States)

    DeKay, Michael L; Greeno, Catherine G; Houck, Patricia R

    2002-01-01

    Gottman and Levenson (2002) report a number of post hoc ordinary least squares regressions to "predict" the length of marriage, given that divorce has occurred. We argue that the type of statistical model they use is inappropriate for answering clinically relevant questions about the causes and timing of divorce, and present several reasons why an alternative family of models called duration models would be more appropriate. The distribution of marriage length is not bimodal, as Gottman and Levenson suggest, and their search for a two-factor model for explaining marriage length is misguided. Their regression models omit many variables known to affect marriage length, and instead use variables that were pre-screened for their predictive ability. Their final model is based on data for only 15 cases, including one unusual case that has undue influence on the results. For these and other technical reasons presented in the text, we believe that Gottman and Levenson's results are not replicable, and that they should not be used to guide interventions for couples in clinical settings.

  15. Family Abduction Outcomes: Factors Associated with Duration and Emotional Trauma to Children.

    Science.gov (United States)

    Plass, Peggy S.; And Others

    1996-01-01

    Examines influences surrounding two specific outcomes of family abduction events: duration of the episode and the likelihood of emotional trauma to children involved. Findings indicate duration is influenced by preparedness, planning and intent, and with difficulty in physically locating the child. Emotional harm is associated with child…

  16. Bone reactions adjacent to titanium implants subjected to static load of different duration. A study in the dog (III)

    DEFF Research Database (Denmark)

    Gotfredsen, K; Berglundh, T; Lindhe, J

    2001-01-01

    The aim of the present experiment was to study the effect of a long-standing lateral static load on the peri-implant bone. Three beagle dogs were used. The mandibular premolars were extracted and 12 weeks later 3 titanium implants (ITI(R) Dental Implant System) were installed in each quadrant....... Crowns were fitted to all implants 12 weeks after the installation procedure. The anterior and central crowns were fused and connected to the posterior crown by an expansion screw. In the right side of the mandible, the expansion screws were activated every 2 weeks during a 46-week period. During...... the last 10 weeks of this period, an expansion force similar to that of the right side was applied in the left. The animals were sacrificed and block biopsies of each implant site harvested and prepared for histological analysis. Sites subjected to 10 weeks or 46 weeks of lateral load had a similar (i...

  17. Factors predicting the duration of adrenal insufficiency in patients successfully treated for Cushing disease and nonmalignant primary adrenal Cushing syndrome.

    Science.gov (United States)

    Prete, Alessandro; Paragliola, Rosa Maria; Bottiglieri, Filomena; Rota, Carlo Antonio; Pontecorvi, Alfredo; Salvatori, Roberto; Corsello, Salvatore Maria

    2017-03-01

    Successful treatment of Cushing syndrome causes transient or permanent adrenal insufficiency deriving from endogenous hypercortisolism-induced hypothalamus-pituitary-adrenal-axis suppression. We analyzed pre-treatment factors potentially affecting the duration of adrenal insufficiency. We conducted a retrospective analysis on patients successfully treated for Cushing disease (15 patients) who underwent transsphenoidal surgery, and nonmalignant primary adrenal Cushing syndrome (31 patients) who underwent unilateral adrenalectomy, divided into patients with overt primary adrenal Cushing syndrome (14 patients) and subclinical primary adrenal Cushing syndrome (17 patients). Epidemiological data, medical history, and hormonal parameters depending on the etiology of hypercortisolism were collected and compared to the duration of adrenal insufficiency. The median duration of follow-up after surgery for Cushing disease and primary adrenal Cushing syndrome was 70 and 48 months, respectively. In the Cushing disease group, the median duration of adrenal insufficiency after transsphenoidal surgery was 15 months: younger age at diagnosis and longer duration of signs and symptoms of hypercortisolism before diagnosis and surgery were associated with longer duration of adrenal insufficiency. The median duration of adrenal insufficiency was 6 months for subclinical primary adrenal Cushing syndrome and 18.5 months for overt primary adrenal Cushing syndrome. The biochemical severity of hypercortisolism, the grade of hypothalamus-pituitary-adrenal-axis suppression, and treatment with ketoconazole before surgery accounted for longer duration of adrenal insufficiency. In patients with Cushing disease, younger age and delayed diagnosis and treatment predict longer need for glucocorticoid replacement therapy after successful transsphenoidal surgery. In patients with primary adrenal Cushing syndrome, the severity of hypercortisolism plays a primary role in influencing the duration of

  18. Change in sleep duration and proposed dietary risk factors for obesity in Danish school children

    DEFF Research Database (Denmark)

    Hjorth, M. F.; Quist, J. S.; Andersen, Rikke

    2014-01-01

    at baseline and after ∼200 days. Results Baseline sleep duration did not predict changes in dietary intake or vice versa (all P ≥ 0.69). However, 1-h lower sleep duration was associated with higher intake of added sugar (1.59 E%; P = 0.001) and sugar-sweetened beverages (0.90 E%; P = 0.002) after 200 days...

  19. Recovery of weak factor loadings when adding the mean structure in confirmatory factor analysis: A simulation study

    Directory of Open Access Journals (Sweden)

    Carmen eXiménez

    2016-01-01

    Full Text Available This article extends previous research on the recovery of weak factor loadings in confirmatory factor analysis 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.

  20. REGULARITIES OF THE INFLUENCE OF ORGANIZATIONAL AND TECHNOLOGICAL FACTORS ON THE DURATION OF CONSTRUCTION OF HIGH-RISE MULTIFUNCTIONAL COMPLEXES

    Directory of Open Access Journals (Sweden)

    ZAIATS Yi. I.

    2015-10-01

    Full Text Available Problem statement. Technical and economic indexes of projects of construction of high-rise multifunctional complexes, namely: the duration of construction works and the cost of building products depends on the technology of construction works and method of construction organization, and on their choice influence the architectural and design, constructional and engineering made decisions. Purpose. To reveal the regularity of influence of organizational and technological factors on the duration of construction of high-rise multifunctional complexes in the conditions of dense city building. Conclusion. To reveal the regularity of the influence of organizational and technological factors (the height, the factor complexity of design of project and and estimate documentation, factor of complexity of construction works, the factor of complexity of control of investment and construction project, economy factor, comfort factor, factor of technology of projected solutions for the duration of the construction of high-rise multifunctional complexes (depending on their height: from 73,5 m to 100 m inclusively; from 100 m to 200 m inclusively allow us to quantitatively assess their influence and can be used in the development of the methodology of substantiation of the expediency and effectiveness of the realization of projects of high-rise construction in condition of compacted urban development, based on the consideration of the influence of organizational and technological aspects.

  1. Effect of Sampling Rates on the Quantification of Forces, Durations, and Rates of Loading of Simulated Side Posture High-Velocity, Low-Amplitude Lumbar Spine Manipulation☆

    Science.gov (United States)

    Gudavalli, Maruti Ram; DeVocht, James; Tayh, Ali; Xia, Ting

    2013-01-01

    Objective Quantification of chiropractic high-velocity, low-amplitude spinal manipulation (HVLA-SM) may require biomechanical equipment capable of sampling data at high rates. However, there are few studies reported in the literature regarding the minimal sampling rate required to record the HVLA-SM force-time profile data accurately and precisely. The purpose of this study was to investigate the effect of different sampling rates on the quantification of forces, durations, and rates of loading of simulated side posture lumbar spine HVLA-SM delivered by doctors of chiropractic. Methods Five doctors of chiropractic (DCs) and 5 asymptomatic participants were recruited for this study. Force-time profiles were recorded during (i) 52 simulated HVLA-SM thrusts to a force transducer placed on a force plate by 2 DCs and (ii) 12 lumbar side posture HVLA-SM on 5 participants by 3 DCs. Data sampling rate of the force plate remained the same at 1000 Hz, whereas the sampling rate of the force transducer varied at 50, 100, 200, and 500 Hz. The data were reduced using custom-written MATLAB (Mathworks, Inc, Natick, MA) and MathCad (version 15; Parametric Technologies, Natick, MA) programs and analyzed descriptively. Results The average differences in the computed durations and rates of loading are smaller than 5% between 50 and 1000 Hz sampling rates. The differences in the computed preloads and peak loads are smaller than 3%. Conclusions The small differences observed in the characteristics of force-time profiles of simulated manual HVLA-SM thrusts measured using various sampling rates suggest that a sampling rate as low as 50 to 100 Hz may be sufficient. The results are applicable to the manipulation performed in this study: manual side posture lumbar spine HVLA-SM. PMID:23790603

  2. Effect of sampling rates on the quantification of forces, durations, and rates of loading of simulated side posture high-velocity, low-amplitude lumbar spine manipulation.

    Science.gov (United States)

    Gudavalli, Maruti Ram; DeVocht, James; Tayh, Ali; Xia, Ting

    2013-06-01

    Quantification of chiropractic high-velocity, low-amplitude spinal manipulation (HVLA-SM) may require biomechanical equipment capable of sampling data at high rates. However, there are few studies reported in the literature regarding the minimal sampling rate required to record the HVLA-SM force-time profile data accurately and precisely. The purpose of this study was to investigate the effect of different sampling rates on the quantification of forces, durations, and rates of loading of simulated side posture lumbar spine HVLA-SM delivered by doctors of chiropractic. Five doctors of chiropractic (DCs) and 5 asymptomatic participants were recruited for this study. Force-time profiles were recorded during (i) 52 simulated HVLA-SM thrusts to a force transducer placed on a force plate by 2 DCs and (ii) 12 lumbar side posture HVLA-SM on 5 participants by 3 DCs. Data sampling rate of the force plate remained the same at 1000 Hz, whereas the sampling rate of the force transducer varied at 50, 100, 200, and 500 Hz. The data were reduced using custom-written MATLAB (Mathworks, Inc, Natick, MA) and MathCad (version 15; Parametric Technologies, Natick, MA) programs and analyzed descriptively. The average differences in the computed durations and rates of loading are smaller than 5% between 50 and 1000 Hz sampling rates. The differences in the computed preloads and peak loads are smaller than 3%. The small differences observed in the characteristics of force-time profiles of simulated manual HVLA-SM thrusts measured using various sampling rates suggest that a sampling rate as low as 50 to 100 Hz may be sufficient. The results are applicable to the manipulation performed in this study: manual side posture lumbar spine HVLA-SM. Copyright © 2013 The Authors. Published by Mosby, Inc. All rights reserved.

  3. Factors associated with first return to work and sick leave durations in workers with common mental disorders

    NARCIS (Netherlands)

    Flach, Peter A.; Groothoff, Johan W.; Krol, Boudien; Bultmann, Ute

    2012-01-01

    Background: Associations are examined between socio-demographic, medical, work-related and organizational factors and the moment of first return to work (RTW) (within or after 6 weeks of sick leave) and total sick leave duration in sick leave spells due to common mental disorders. Methods: Data are

  4. 14 CFR 23.527 - Hull and main float load factors.

    Science.gov (United States)

    2010-01-01

    ....012 (except that this factor may not be less than that necessary to obtain the minimum value of step... landing cases EC28SE91.005 (b) The following values are used: (1) nw=water reaction load factor (that is..., from the center of gravity of the seaplane to the hull longitudinal station at which the load factor is...

  5. An evaluation of factors affecting duration of treatment with repetitive transcranial magnetic stimulation for depression

    Directory of Open Access Journals (Sweden)

    Roni Broder Cohen

    2007-12-01

    Full Text Available Objective: To investigate the effects of repetitive transcranialmagnetic stimulation in patients with major depression who weresubmitted to this treatment during the period from 2000 to 2006.Methods: A retrospective study with 204 patients who underwenttreatment with repetitive transcranial magnetic stimulation, collectingdata from those who experienced remission (defined as a HDRS scoreequal to or lower than 7. The patients were followed for up to 6 monthsafter treatment. Mean duration of remission for this cohort of patientswas 70.2 (± 58.4 days. Results: The only variable associated withthe duration of remission in the linear regression model was numberof repetitive transcranial magnetic stimulation sessions. Conclusion:Our findings suggest that the greater the number of sessions, the longerthe duration of repetitive transcranial magnetic stimulation effects.Consequently, future research investigating the effects of repetitivetranscranial magnetic stimulation should explore this variable in orderto maximize the therapeutic effects of this new brain stimulationtechnique.

  6. Reliability-Based Load and Resistance Factors Design for Offshore Jacket Platforms in the Bohai Bay: Calibration on Design Factors

    Institute of Scientific and Technical Information of China (English)

    JIN Wei-liang; HU Qi-zhong; SHEN Zhao-wei; SHI Zhong-min

    2009-01-01

    For the fulfillment of the probability-based structural design for the offshore jacket platforms in the Bohai Bay, the design factors of loads, resistance and load combinations are much necessary to be calibrated according to the proposed target reliability index. Firstly, the limit states function for the offshore jacket platforms is introduced. Then, four ap-proaches to calibrate the factors of load and resistance are presented and compared. Afterwards, the methods to calibrate the load combination factors are developed. Finally, the factors of load, resistance and load combination for the offshore jacket platforms in the Bohai Bay are calibrated and the corresponding design formulae are recommended. The results are proved to be rational in practice, and also illustrate that the proposed target reliability index for offshore jacket platforms in the Bohai Bay is also appropriate.

  7. Gastric emptying scintigraphy results in children are affected by age, anthropometric factors, and study duration

    Science.gov (United States)

    A standardized 4-hour adult-based gastric emptying scintigraphy (GES) protocol is increasingly being used in children to evaluate for gastroparesis. We sought to determine the effect of age, anthropometrics, and study duration on GES results using this protocol in children. Retrospective review of c...

  8. Socioeconomic driving factors of nitrogen load from food consumption and preventive measures.

    Science.gov (United States)

    Liu, Chen; Fei, Jinling; Hayashi, Yoshitsugu; Yasunari, Tetsuzo

    2014-09-01

    To diagnose environmental nitrogen (N) load from food consumption and to suggest preventive measures, this study identified relationships between nitrogen load from food consumption and driving factors by examining six representative countries and regions for the period 1970-2009 as an example. The logarithmic mean Divisia index technique was used to disassemble nitrogen load growth into four driving factors: population, economic activity, food intensity of the economy, and nitrogen content of food. In all study areas, increased economic activity was the main factor driving nitrogen load increase. The positive effect of population growth was relatively small but not negligible and changes in food intensity had a decreasing effect on nitrogen load. Changes in nitrogen content of food varied between areas. Broad strategies to reduce and mitigate nitrogen loading and decouple nitrogen load from economic growth in both developed and developing countries are suggested.

  9. Risk Factors for Extended Duration of Acute Diarrhea in Young Children

    OpenAIRE

    Tor A. Strand; Sharma, Pushpa R.; Håkon K Gjessing; Manjeswori Ulak; Chandyo, Ram K; Adhikari, Ramesh K.; Halvor Sommerfelt

    2012-01-01

    Objective and Background: We sought to identify predictors of extended duration of diarrhea in young children, which contributes substantially to the nearly 1 1/2 million annual diarrheal deaths globally. Methods: We followed 6-35 month old Nepalese children enrolled in the placebo-arm of a randomized controlled trial with 391 episodes of acute diarrhea from the day they were diagnosed until cessation of the episode. Using multiple logistic regression analysis, we identified independent risk ...

  10. Factors associated to duration of hepatitis A outbreaks: implications for control

    OpenAIRE

    Torner Gràcia, Núria; Broner, Sonia; Martinez, Ana; Tortajada, Cecilia; Garcia de Olalla, Patricia; Barrabeig i Fabregat, Irene; Sala, Maria Rosa; Camps, Neus; Minguell, Sofia; Álvarez, Josep; Ferrús, Gloria; Torra, Roser; Godoy i García, Pere; Domínguez García, Àngela

    2012-01-01

    Even though hepatitis A mass vaccination effectiveness is high, outbreaks continue to occur. The aim of this study was to investigate the association between duration and characteristics of hepatitis A outbreaks. Hepatitis A (HA) outbreaks reported between 1991 and 2007 were studied. An outbreak was defined as $2 epidemiologically-linked cases with $1 case laboratory-confirmed by detection of HA immunoglobulin M (IgM) antibodies. Relationships between explanatory variables and out...

  11. Factors Associated to Duration of Hepatitis A Outbreaks: Implications for Control

    OpenAIRE

    Torner Gràcia, Núria; Broner, Sonia Judith; Martinez, Ana; Tortajada, Cecilia; García de Olalla, Patricia; Barrabeig i Fabregat, Irene; Sala, Maria Rosa; Camps, Neus; Minguell, Sofia; Alvarez, Josep; Ferrús, Gloria; Torra, Roser; Godoy i García, Pere; Domínguez García, Àngela; Hepatitis A Surveillance Group of Catalonia

    2012-01-01

    Even though hepatitis A mass vaccination effectiveness is high, outbreaks continue to occur. The aim of this study was to investigate the association between duration and characteristics of hepatitis A outbreaks. Hepatitis A (HA) outbreaks reported between 1991 and 2007 were studied. An outbreak was defined as ≥2 epidemiologically-linked cases with ≥1 case laboratory-confirmed by detection of HA immunoglobulin M (IgM) antibodies. Relationships between explanatory variables and outbreak durati...

  12. Genomic Loads and Genotypes of Respiratory Syncytial Virus: Viral Factors during Lower Respiratory Tract Infection in Chilean Hospitalized Infants

    Science.gov (United States)

    Espinosa, Yazmín; San Martín, Camila; Torres, Alejandro A.; Farfán, Mauricio J.; Torres, Juan P.; Avadhanula, Vasanthi; Piedra, Pedro A.; Tapia, Lorena I.

    2017-01-01

    The clinical impact of viral factors (types and viral loads) during respiratory syncytial virus (RSV) infection is still controversial, especially regarding newly described genotypes. In this study, infants with RSV bronchiolitis were recruited to describe the association of these viral factors with severity of infection. RSV antigenic types, genotypes, and viral loads were determined from hospitalized patients at Hospital Roberto del Río, Santiago, Chile. Cases were characterized by demographic and clinical information, including days of lower respiratory symptoms and severity. A total of 86 patients were included: 49 moderate and 37 severe cases. During 2013, RSV-A was dominant (86%). RSV-B predominated in 2014 (92%). Phylogenetic analyses revealed circulation of GA2, Buenos Aires (BA), and Ontario (ON) genotypes. No association was observed between severity of infection and RSV group (p = 0.69) or genotype (p = 0.87). After a clinical categorization of duration of illness, higher RSV genomic loads were detected in infants evaluated earlier in their disease (p < 0.001) and also in infants evaluated later, but coursing a more severe infection (p = 0.04). Although types and genotypes did not associate with severity in our children, higher RSV genomic loads and delayed viral clearance in severe patients define a group that might benefit from new antiviral therapies. PMID:28335547

  13. 14 CFR 25.527 - Hull and main float load factors.

    Science.gov (United States)

    2010-01-01

    ... not be less than that necessary to obtain the minimum value of step load factor of 2.33). (3) V S 0... following values are used: (1) n W=water reaction load factor (that is, the water reaction divided by... of distance, measured parallel to hull reference axis, from the center of gravity of the seaplane to...

  14. Maximum Likelihood Estimation of Time-Varying Loadings in High-Dimensional Factor Models

    DEFF Research Database (Denmark)

    Mikkelsen, Jakob Guldbæk; Hillebrand, Eric; Urga, Giovanni

    In this paper, we develop a maximum likelihood estimator of time-varying loadings in high-dimensional factor models. We specify the loadings to evolve as stationary vector autoregressions (VAR) and show that consistent estimates of the loadings parameters can be obtained by a two-step maximum...... likelihood estimation procedure. In the first step, principal components are extracted from the data to form factor estimates. In the second step, the parameters of the loadings VARs are estimated as a set of univariate regression models with time-varying coefficients. We document the finite...

  15. Factor Analysis of the Aggregated Electric Vehicle Load Based on Data Mining

    Directory of Open Access Journals (Sweden)

    Yao Wang

    2012-06-01

    Full Text Available Electric vehicles (EVs and the related infrastructure are being developed rapidly. In order to evaluate the impact of factors on the aggregated EV load and to coordinate charging, a model is established to capture the relationship between the charging load and important factors based on data mining. The factors can be categorized as internal and external. The internal factors include the EV battery size, charging rate at different places, penetration of the charging infrastructure, and charging habits. The external factor is the time-of-use pricing (TOU policy. As a massive input data is necessary for data mining, an algorithm is implemented to generate a massive sample as input data which considers real-world travel patterns based on a historical travel dataset. With the input data, linear regression was used to build a linear model whose inputs were the internal factors. The impact of the internal factors on the EV load can be quantified by analyzing the sign, value, and temporal distribution of the model coefficients. The results showed that when no TOU policy is implemented, the rate of charging at home and range anxiety exerts the greatest influence on EV load. For the external factor, a support vector regression technique was used to build a relationship between the TOU policy and EV load. Then, an optimization model based on the relationship was proposed to devise a TOU policy that levels the load. The results suggest that implementing a TOU policy reduces the difference between the peak and valley loads remarkably.

  16. Severe tardive dystonia on low dose short duration exposure to atypical antipsychotics: Factors explored

    Directory of Open Access Journals (Sweden)

    Nilanjan C Chandra

    2017-01-01

    Full Text Available Tardive dystonia (TD is a serious side effect of antipsychotic medications, more with typical antipsychotics, that is potentially irreversible in affected patients. Studies show that newer atypical antipsychotics have a lower risk of TD. As a result, many clinicians may have developed a false sense of security when prescribing these medications. We report a case of 20-year-old male with hyperthymic temperament and borderline intellectual functioning, who developed severe TD after low dose short duration exposure to atypical antipsychotic risperidone and then olanzapine. The goal of this paper is to alert the reader to be judicious and cautious before using casual low dose second generation antipsychotics in patient with no core psychotic features, hyperthymic temperament, or borderline intellectual functioning suggestive of organic brain damage, who are more prone to develop adverse effects such as TD and monitor the onset of TD in patients taking atypical antipsychotics.

  17. Severe Tardive Dystonia on Low Dose Short Duration Exposure to Atypical Antipsychotics: Factors Explored

    Science.gov (United States)

    Chandra, Nilanjan C.; Sheth, Shabina A.; Mehta, Ritambhara Y.; Dave, Kamlesh R.

    2017-01-01

    Tardive dystonia (TD) is a serious side effect of antipsychotic medications, more with typical antipsychotics, that is potentially irreversible in affected patients. Studies show that newer atypical antipsychotics have a lower risk of TD. As a result, many clinicians may have developed a false sense of security when prescribing these medications. We report a case of 20-year-old male with hyperthymic temperament and borderline intellectual functioning, who developed severe TD after low dose short duration exposure to atypical antipsychotic risperidone and then olanzapine. The goal of this paper is to alert the reader to be judicious and cautious before using casual low dose second generation antipsychotics in patient with no core psychotic features, hyperthymic temperament, or borderline intellectual functioning suggestive of organic brain damage, who are more prone to develop adverse effects such as TD and monitor the onset of TD in patients taking atypical antipsychotics.

  18. Factors Associated with the Duration of Moderate-to-Severe Diarrhea among Children in Rural Western Kenya Enrolled in the Global Enteric Multicenter Study, 2008-2012.

    Science.gov (United States)

    Schilling, Katharine A; Omore, Richard; Derado, Gordana; Ayers, Tracy; Ochieng, John B; Farag, Tamer H; Nasrin, Dilruba; Panchalingam, Sandra; Nataro, James P; Kotloff, Karen L; Levine, Myron M; Oundo, Joseph; Parsons, Michelle B; Bopp, Cheryl; Laserson, Kayla; Stauber, Christine E; Rothenberg, Richard; Breiman, Robert F; O'Reilly, Ciara E; Mintz, Eric D

    2017-07-01

    Diarrheal disease is a leading cause of death among young children worldwide. As rates of acute diarrhea (AD; 1-6 days duration) have decreased, persistent diarrhea (PD; > 14 days duration) accounts for a greater proportion of the diarrheal disease burden. We describe factors associated with the duration of moderate-to-severe diarrhea in Kenyan children diarrhea (ProAD; 7-13 days duration), and 73 (7%) had PD. We constructed a Cox proportional hazards model to identify factors associated with diarrheal duration. Risk factors independently associated with longer diarrheal duration included infection with Cryptosporidium (hazard ratio [HR]: 0.868, P = 0.035), using an unimproved drinking water source (HR: 0.87, P = 0.035), and being stunted at enrollment (HR: 0.026, P improve drinking water are imperative, and nutrition should be improved through exclusive breastfeeding in infants ≤ 6 months and appropriate continued feeding practices for ill children.

  19. Mental health problems of young refugees: duration of settlement, risk factors and community-based interventions.

    Science.gov (United States)

    Durà-Vilà, Glòria; Klasen, Henrika; Makatini, Zethu; Rahimi, Zohreh; Hodes, Matthew

    2013-10-01

    Little is known about the characteristics of young psychologically-distressed refugees in mental health services, and how they vary according to the duration of settlement. This study of 102 young refugees referred to a community-based mental health service describes past adversities and current circumstances, referral problems, service utilization and treatment outcomes using the Strengths and Difficulties Questionnaire (SDQ). The more recently-arrived refugees had significantly higher levels of close exposure to war and violence, were more likely to have suffered separation from immediate family and to have insecure legal status. Those refugees settled longer were significantly more likely to be referred because of conduct problems while there was a trend in recent arrivals to present with internalizing pathology. A comparison of the teachers' and parents' mean SDQ scores of the study's young refugees sample and a national study representative of Great Britain as a whole showed that young refugees have higher scores in total problem and all subscales scores than the British scores. Community-based mental health services for young refugees appeared effective - significant improvement was found in SDQ scores for the sub-group (n = 24) who took up the treatments offered. The implications are discussed for service development and practitioners.

  20. The effects of aerobic exercise intensity and duration on levels of brain-derived neurotrophic factor in healthy men.

    Science.gov (United States)

    Schmolesky, Matthew T; Webb, David L; Hansen, Rodney A

    2013-01-01

    This study examined the combined effects of aerobic exercise intensity and duration on serum brain-derived neurotrophic factor (sBDNF) levels in healthy human adult males aged 18-25 years. Forty five participants were randomly assigned to one of six exercise conditions based on varying intensity (80% or 60% of heart rate reserve, or control) and duration (20 or 40 min). Vigorous (80% heart rate reserve, "Vig") and moderate (60% heart rate reserve, "Mod") exercise was carried out on cycle ergometers. Control subjects remained seated and at rest during the exercise period. Pre- and post-exercise blood draws were conducted and sBDNF measured. Physical exercise caused an average ~ 32% increase in sBDNF levels relative to baseline that resulted in concentrations that were 45% higher than control conditions. Comparing the six conditions, sBDNF levels rose consistently among the four exercise conditions (Vig20 = 26.38 ± 34.89%, Vig40 = 28.48 ± 19.11%, Mod20 = 41.23 ± 59.65%, Mod40 = 30.16 ± 72.11%) and decreased consistently among the controls (Con20 = -14.48 ± 16.50, Con40 = -10.51 ± 26.78). Vig conditions had the highest proportion of subjects that experienced a significant (? 10%) increase in sBDNF levels, followed by Mod and control conditions. An analysis of modeled sBDNF integrals (area under the curve) demonstrated substantially greater values for Vig40 and Mod40 conditions compared to Vig20 and Mod20 conditions. Collectively, these results demonstrate that neither duration (20 vs. 40 min) nor intensity (60 vs. 80% HR reserve) significantly affects the benefits of exercise if only the sBDNF increase at a single post-exercise time point is considered. However, when comparing either the probability of achieving a significant BDNF gain or the integral (i.e. the volume of circulating BDNF over time) the Vig40 condition offers maximal benefits. Thus, we conclude that the future study of aerobic exercise effects on BDNF-mediated neuroprotection should take the

  1. Driving Factors of the Decadal Variations in Sunshine Duration and Surface Solar Radiation in China

    Science.gov (United States)

    Wang, Y.; Yang, Y.; Wild, M.

    2016-12-01

    Solar radiation received at the Earth's surface has not been stable over time but underwent substantial decadal variations, popularly known as global dimming and brightening. Consistently in China, a reversal was noted in sunshine duration (SD), a widely used proxy for surface solar radiation (SSR), from dimming by -0.17 h d-1 decade-1 for the period 1960-1989 to leveling off by -0.01 h d-1 decade-1 for 1990-2013. SD declines covered about 85% of 344 examined sites across China in the dimming phase. By contrast, in the brightening phase, SD increased in about half of China, while continued to decrease in the other half, especially in central and north China. Through trend comparison and grey relational analysis, it was proven that the decadal changes in SD in China were driven by air pollution rather than cloud——the two most likely candidates for explaining global dimming and brightening. The air pollution effect on SD and SSR was then quantified under clear-sky conditions as follows: (1) on pristine days, SD is on average 1.1 h d-1 (12.4%) longer than on polluted days; and (2) on average, when air pollution increases by one level, i.e. the index for air pollution (API) increases by 50, SSR decreases by 6 W m-2. API was shown to be a useful indicator in studying the effects of aerosols on global dimming and brightening. Besides, air pollution has driven wind speed into a non-negligible regulator of SSR. The regulatory effect of wind speed on SSR starts to be important when API exceeds the level of 125. In addition, in the dimming phase without available API monitoring, urbanization can be used as an applicable proxy for anthropogenic pollution level. Urbanization has significantly affected SD trends in China until the brightening phase when pollution regulations became effective.

  2. Anterior cruciate ligament injuries in soccer: Loading mechanisms, risk factors, and prevention programs

    Directory of Open Access Journals (Sweden)

    Boyi Dai

    2014-12-01

    Full Text Available Anterior cruciate ligament (ACL injuries are common in soccer. Understanding ACL loading mechanisms and risk factors for ACL injury is critical for designing effective prevention programs. The purpose of this review is to summarize the relevant literature on ACL loading mechanisms, ACL injury risk factors, and current ACL injury prevention programs for soccer players. Literature has shown that tibial anterior translation due to shear force at the proximal end of tibia is the primary ACL loading mechanism. No evidence has been found showing that knee valgus moment is the primary ACL loading mechanism. ACL loading mechanisms are largely ignored in previous studies on risk factors for ACL injury. Identified risk factors have little connections to ACL loading mechanisms. The results of studies on ACL injury prevention programs for soccer players are inconsistent. Current ACL injury prevention programs for soccer players are clinically ineffective due to low compliance. Future studies are urgently needed to identify risk factors for ACL injury in soccer that are connected to ACL loading mechanisms and have cause-and-effect relationships with injury rate, and to develop new prevention programs to improve compliance.

  3. The Effect of External Factors on Consumption Electricity Loads Forecasting using Fuzzy Takagi-Sugeno Kang

    National Research Council Canada - National Science Library

    Gayatri Dwi Santika; wayan f mahmudy

    2017-01-01

    .... The results of the study came to the conclusion that Fuzzy Inference System Sugeno method using external factors to forecast the consumption of electrical load gives a better result than Fuzzy...

  4. Antarctica Meta-Analysis: Psychosocial Factors Related to Long Duration Isolation and Confinement

    Science.gov (United States)

    Leveton, Lauren; Shea, Camille; Slack, Kelley J.; Keeton, Kathryn E.; Palinkas, Lawrence A.

    2009-01-01

    This meta-analysis is examining the psychological effects of wintering-over in Antarctica. As an isolated, confined, and extreme (ICE) environment, Antarctica provides invaluable opportunities to experience stressors more common to spaceflight than to the average person s everyday life. Increased prevalence of psychological symptoms, syndromes, and psychiatric disorders, as well as positive effects, are expected to be associated with various demographic and environmental factors. Implications for spaceflight are discussed. Findings from statistical review of the Antarctic articles will be shared.

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

    Science.gov (United States)

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

    2013-05-01

    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

  6. The Effect of External Factors on Consumption Electricity Loads Forecasting using Fuzzy Takagi-Sugeno Kang

    Directory of Open Access Journals (Sweden)

    Gayatri Dwi Santika

    2017-03-01

    Full Text Available This study applied Fuzzy Inference System Sugeno to forecast electrical load by considering the external factors. To see the accuracy of forecasting using Fuzzy Inference System Sugeno, then a comparison between the forecasting results of Fuzzy Inference System Sugeno using historical data with Fuzzy Inference System Sugeno using external factors was done. By using external factors method, resulted the smallest RMSE of 0762 and using historical data obtained error (RMSE of 1028. The results of the study came to the conclusion that Fuzzy Inference System Sugeno method using external factors to forecast the consumption of electrical load gives a better result than Fuzzy Inference System Sugeno using only historical data.

  7. Impact of Bulldozer's Engine Load Factor on Fuel Consumption, CO2 Emission and Cost

    Directory of Open Access Journals (Sweden)

    V. Kecojevic

    2011-01-01

    Full Text Available Problem statement: Bulldozers consume a large amount of diesel fuel and consequently produce a significant quantity of CO2. Environmental and economic cost issues related to fuel consumption and CO2 emission represent a substantial challenge to the mining industry. Approach: Impact of engine load conditions on fuel consumption and the subsequent CO2 emission and cost was analyzed for Caterpillar bulldozers. Results were compared with the data on bulldozers' fuel consumption from an operating coal surface mine in the United States. Results: There is a strong linear correlation among power, fuel consumption and engine load factor. Reduction in load factor by 15% may significantly reduce the fuel consumption and the CO2 emission. Conclusion/Recommendation: Application of appropriate bulldozer's load factor may help mine operators manage fuel consumption, cost and environmental burden.

  8. Factores que influyen en el abandono temprano de la lactancia por mujeres trabajadoras Factors associated with short duration of breast-feeding in Mexican working women

    Directory of Open Access Journals (Sweden)

    Manuel Navarro-Estrella

    2003-08-01

    Full Text Available OBJETIVO: Identificar los factores maternos, laborales y de los servicios de salud que influyen en el abandono temprano de la lactancia materna en madres trabajadoras. MATERIAL Y MÉTODOS: Entre noviembre de 1998 y marzo de 1999 se efectuó un estudio transversal comparativo con madres derechohabientes del Instituto Mexicano del Seguro Social de Ensenada, Baja California, México. A 265 madres se les aplicó un cuestionario entre los tres y nueve meses posparto. Se distribuyeron en: grupo I: madres con abandono temprano de la lactancia materna; grupo II: madres que prolongaron la lactancia materna por más de tres meses. Para identificar los factores asociados con el abandono temprano de la lactancia materna, se utilizó regresión logística. RESULTADOS: El 42.3% (112 de las madres abandonaron temprano la lactancia materna. Los factores de riesgo fueron: tener conocimientos malos sobre lactancia materna, OR 5.97 (IC 95% 1.67-20.67, la ausencia del antecedente de haberla practicado en un hijo previo OR 2.98 (IC 95% 1.66-5.36, tener un plan de duración de la misma de 0 a 3 meses, OR 16.24 (IC 95% 5.37-49.12, y la falta de facilidades en el trabajo para efectuarla, OR 1.99 (IC 95% 1.12-3.56. CONCLUSIONES: Los principales factores asociados con el abandono temprano de la lactancia materna fueron maternos. El único factor laboral fue la ausencia de facilidades para amamantar. Es probable que la calidad de los conocimientos, la experiencia previa con ella y tener facilidades laborales influyan en la decisión de prolongarla.OBJECTIVE:To identify the maternal, work, and health services factors associated with a short duration of breast-feeding in working mothers. MATERIAL AND METHODS: A cross-sectional study was carried out between November 1998 and March 1999, among 265 mothers medically insured by (Instituto Mexicano del Seguro Social, IMSS Mexican Institute of Social Security, who completed a questionnaire when their babies were 3 to 9 months old

  9. Factors associated with breastfeeding duration and exclusivity in mothers returning to paid employment postpartum.

    Science.gov (United States)

    Bai, Dorothy Li; Fong, Daniel Yee Tak; Tarrant, Marie

    2015-05-01

    Mothers who are employed postpartum are less likely to continue breastfeeding than mothers who are not formally employed. However, as postpartum employment is increasingly necessary for the majority of new mothers, it is important to investigate factors that influence the continuation of breastfeeding in employed mothers. A sample of 1,738 mothers who returned to paid employment postpartum were recruited from the obstetric units of four public hospitals in Hong Kong, and prospectively followed for 12 months or until their infant was weaned. More than 85 % of participants returned to formal employment within 10 weeks postpartum, with over 90 % of these employed full-time. About one-third of the participants (32 %) were able to combine breastfeeding and employment, with breastfeeding defined as continuing for more than 2 weeks after returning to work postpartum. Later return to work and higher maternal education were associated with new mothers being able to combine breastfeeding and employment. Later return to work, shorter working hours, parental childcare, and higher maternal education were also associated with less likelihood of weaning from any or exclusive breastfeeding. Improvements in employment-related conditions for mothers and additional support for lower educated mothers may be effective strategies to enable employed women to continue breastfeeding after their return to work.

  10. [Breastfeeding (part one): Frequency, benefits and drawbacks, optimal duration and factors influencing its initiation and prolongation. Clinical guidelines for practice].

    Science.gov (United States)

    Chantry, A A; Monier, I; Marcellin, L

    2015-12-01

    The objectives were to on assess the frequency and the duration of breastfeeding in France. On the other hand, the objectives were to identify its benefits and drawbacks, and to study the factors influencing its initiation and its extension. Bibliographic research in Medline, Google Scholar and in the Cochrane Library. Breastfeeding concerns in France about 70% of children at birth (EL2). Its median duration is about 15 weeks and 3 weeks ½ for exclusive breastfeeding. At three months, only one third of children breastfed at birth are still being breastfed (EL2). Whether this is due to the composition of breast milk or the behavior of mothers with their children or their socio-cultural level, or even by all these components at once, breastfeeding is associated with better cognitive development children (EL2). This effect is even more reinforced that mothers breastfeed exclusively and prolonged (EL2). As part of the prevention of many diseases (ear infections, gastrointestinal infections, atopic diseases, obesity and cardiovascular diseases…), exclusive and prolonged breastfeeding (grade B) between 4 to 6 months is recommended (professional consensus). Breastfeeding is not a means of preventing postpartum depression (professional consensus). To reduce the incidence of breast cancer, prolonged breastfeeding is recommended (grade B). In order to increase the rate of initiation of breastfeeding as well as its duration, it is recommended that health professionals work closely with mothers in their project (grade A), the breastfeeding promotion messages include message to husbands (grade B), and to promote breastfeeding on demand without fixed interval between feedings (grade B). However, there is not enough data to recommend the use of a specific position during breastfeeding, or the use of one or two breast or to early start breastfeeding or not (professional consensus). Exclusive and extended breastfeeding is recommended (grade B) between 4 to 6 months (professional

  11. Factors Associated with Adherence to and Treatment Duration of Erlotinib Among Patients with Non-Small Cell Lung Cancer.

    Science.gov (United States)

    Hess, Lisa M; Louder, Anthony; Winfree, Katherine; Zhu, Yajun E; Oton, Ana B; Nair, Radhika

    2017-06-01

    In lung cancer, there is an increasing number of oral agents available for patients; however, little is known about the factors associated with adherence to and treatment duration on oral medications in non-small cell lung cancer (NSCLC). To evaluate the clinical and demographic factors associated with adherence and treatment discontinuation, respectively, to oral oncolytics among patients with NSCLC. A retrospective, claims-based analysis of the Humana Research Database supplemented with medical chart review was conducted among patients with NSCLC who started an oral oncolytic between January 1, 2008, and June 30, 2013. Patients were required to be enrolled at least 1 year before the start of oral oncolytics and have no evidence of any oral oncolytic use during this period. Logistic regression models and Cox proportional hazard models were used to identify predictors associated with medication adherence and treatment duration, respectively. Among all oral oncolytics, only the cohort starting on erlotinib had sufficient sample size (n = 1,452). A wide variety of factors were found to be associated with adherence. Low-income subsidy status, previous use of intravenous chemotherapy, and lower total baseline health care costs were significantly related to decreasing adherence (each P patient out-of-pocket cost was associated with decreasing adherence to erlotinib (P patient outcomes that may be associated with low adherence to or shorter treatment duration on oral chemotherapy. This study was supported by funding from Eli Lilly and Company to Comprehensive Health Insights, a Humana company, as a collaborative research project involving employees of both companies. Hess, Winfree, Zhu, and Oton are employees of Eli Lilly and Company. Louder and Nair are employees of Comprehensive Health Insights, which received funding to complete this research. Study concept and design were contributed by Hess, Zhu, Winfree, and Oton. Nair and Louder collected the data, and data

  12. Sensitivity Factor Analysis For Unit Commitment In Loaded Lines

    Directory of Open Access Journals (Sweden)

    Lata Chaudhary

    2016-05-01

    Full Text Available In today’s competitive electricity market, it is not possible to settle all contracted transactions of power because of congestion in transmission lines. Usually, the independent system operator seeks to eliminate congestion by rescheduling output power of the generators. But all generators may not have the same effect (sensitivity on the power flow of the congested lines, so this is not an economical way to reschedule output power of all generators for managing congestion. Therefore, in this paper, active power generator sensitivity factor of the generators to the congested lines have been utilized to ascertain the number of generators participating in congestion management. The effectiveness and feasibility of the proposed algorithm have been tested on IEEE 30 bus system

  13. Environmental load factors and system strength evaluation of offshore jacket platforms

    CERN Document Server

    Nizamani, Zafarullah

    2015-01-01

    This book presents a study for the determination of environmental load factors for Jacket Platforms in Malaysia and a methodology to determine the life extension of aging platforms. The simplified methods described here could be used for determining not only structural reliability but also safety factors. Its content is particularly interesting to design and maintenance engineers who are working in offshore or onshore industry.

  14. [Factors affecting the duration of maternal breast-feeding in a cohort of urban mothers studied longitudinally].

    Science.gov (United States)

    Ruiz, F J; Cravioto, A

    1989-11-01

    A prospective study on the incidence and duration of breastfeeding in a cohort of urban women of the city of Tlaxcala was carried-out in a private pediatric clinic from January, 1983 to December, 1987. In a total of 547 women studied, breastfeeding had a median of three months, and only 5% of the children continued to be breastfed at one year of age. Family tradition of breastfeeding, late introduction of solid foods and/or whole milk and less formal education of the mother were factors related with breastfeeding beyond three months. About 70% of the mothers weaned their children claiming a rejection of the breast-milk by the child, a lack of sufficient quantity to fulfill the child's needs or because of their work outside the home.

  15. EFFECT OF GEAR WIDTH AND HELIX ANGLE ON FACTOR OF DYNAMIC LOAD OF DOUBLE CIRCULAR ARC HELICAL GEARING

    Institute of Scientific and Technical Information of China (English)

    Wu Baolin

    2004-01-01

    Based on theory of mechanical dynamics, meshing characteristic as well as the dynamic model of double circular arc helical gearing, an analysis approach and a computer program have been developed for studying the state of dynamic load and factor of dynamic load of the gearing, the changing situation of dynamic load and dynamic load factor vs some affecting factors such as gear width, helix angle and accuracy grade etc are investigated. A series of conclusions are obtained: ①With the increasing in the values of gear width, the dynamic load factor appears slow decreasing tendency in most region of gear width. ② When the accuracy grades of the gearing are improved, the values of dynamic load factor decrease. ③ The value of dynamic load factor appears a decreasing tendency with the increasing of value of helix angle at the same ratio of critical rotational speed.

  16. Effect of opium addiction on new and traditional cardiovascular risk factors: do duration of addiction and route of administration matter?

    Directory of Open Access Journals (Sweden)

    Naderi Gholam-Ali

    2008-11-01

    Full Text Available Abstract Background There is a belief among some society that opium has a number of beneficial effects on cardiovascular disease. The aim of the present investigation as a cross-sectional study was to assess this hypothesis. Several biochemical factors (Fasting blood sugar, Cholesterol, Triglyceride, LDL-Cholesterol, HDL-Cholesterol, HbA1C, CRP, Fibrinogen, Factor VII, SGOT, SGPT, Lpa, apo A and apo B were evaluated in opium-addicted men (case against non opium-addicted men(control. Three hundred and sixty opium-addicted men were divided into three groups according to the route of administration (Orally, Vafour and Sikh-Sang and each group was divided into four subgroups according to the duration of addiction (5 months, 1 year, 2 years and 5 years. Blood morphine concentration was measured by ELISA method. Results The results show that morphine concentration was significantly higher in orally administration. In all routes, there was a direct correlation between blood morphine concentration and period of addiction. Regardless to the period and route of administration, the level of HbA1C, CRP, factor VII, Fibrinogen, apo B, Lpa, SGOT, and SGPT were significantly higher in the case subjects as compared with controls and HDL-Cholesterol and apo a were significantly lower in the case subjects. Conclusion This study demonstrated the deleterious effects of opium on some traditional and new cardiovascular disease risk factors. These deleterious effects are related to the period of addiction and their levels are significantly increased after 2 years of addiction. Route of administration impresses cardiovascular risk factors and "Sikh-Sang" showed the worst effect.

  17. Intelligent power factor compensation equipment of three phase low voltage loads

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    An intelligent power factor correction scheme is presented for three phase low power factor loads. This new scheme is able to perform individual phase sensing of parameters by monitoring at all times to sense a change in system parameters and affects individual phase correction by applying the exact amount of reactive components needed for each phase, and can also reduce negative sequence current caused by the load to improve system balance. An optimization criterion is used for the proper calculation of reactive power steps in a power compensation installation of capacitor banks. The criterion is enabled by sampling measurements performed on the electrical plant examined within specific interval of time.

  18. THE EFFECTS OF AEROBIC EXERCISE INTENSITY AND DURATION ON LEVELS OF BRAIN-DERIVED NEUROTROPHIC FACTOR IN HEALTHY MEN

    Directory of Open Access Journals (Sweden)

    Matthew T. Schmolesky

    2013-09-01

    Full Text Available This study examined the combined effects of aerobic exercise intensity and duration on serum brain-derived neurotrophic factor (sBDNF levels in healthy human adult males aged 18-25 years. Forty five participants were randomly assigned to one of six exercise conditions based on varying intensity (80% or 60% of heart rate reserve, or control and duration (20 or 40 min. Vigorous (80% heart rate reserve, "Vig" and moderate (60% heart rate reserve, "Mod" exercise was carried out on cycle ergometers. Control subjects remained seated and at rest during the exercise period. Pre- and post-exercise blood draws were conducted and sBDNF measured. Physical exercise caused an average ~ 32% increase in sBDNF levels relative to baseline that resulted in concentrations that were 45% higher than control conditions. Comparing the six conditions, sBDNF levels rose consistently among the four exercise conditions (Vig20 = 26.38 ± 34.89%, Vig40 = 28.48 ± 19.11%, Mod20 = 41.23 ± 59.65%, Mod40 = 30.16 ± 72.11% and decreased consistently among the controls (Con20 = -14.48 ± 16.50, Con40 = -10.51 ± 26.78. Vig conditions had the highest proportion of subjects that experienced a significant (> 10% increase in sBDNF levels, followed by Mod and control conditions. An analysis of modeled sBDNF integrals (area under the curve demonstrated substantially greater values for Vig40 and Mod40 conditions compared to Vig20 and Mod20 conditions. Collectively, these results demonstrate that neither duration (20 vs. 40 min nor intensity (60 vs. 80% HR reserve significantly affects the benefits of exercise if only the sBDNF increase at a single post-exercise time point is considered. However, when comparing either the probability of achieving a significant BDNF gain or the integral (i.e. the volume of circulating BDNF over time the Vig40 condition offers maximal benefits. Thus, we conclude that the future study of aerobic exercise effects on BDNF-mediated neuroprotection should take

  19. Nerve growth factor loaded heparin/chitosan scaffolds for accelerating peripheral nerve regeneration.

    Science.gov (United States)

    Li, Guicai; Xiao, Qinzhi; Zhang, Luzhong; Zhao, Yahong; Yang, Yumin

    2017-09-01

    Artificial chitosan scaffolds have been widely investigated for peripheral nerve regeneration. However, the effect was not as good as that of autologous grafts and therefore could not meet the clinical requirement. In the present study, the nerve growth factor (NGF) loaded heparin/chitosan scaffolds were fabricated via electrostatic interaction for further improving nerve regeneration. The physicochemical properties including morphology, wettability and composition were measured. The heparin immobilization, NGF loading and release were quantitatively and qualitatively characterized, respectively. The effect of NGF loaded heparin/chitosan scaffolds on nerve regeneration was evaluated by Schwann cells culture for different periods. The results showed that the heparin immobilization and NGF loading did not cause the change of bulk properties of chitosan scaffolds except for morphology and wettability. The pre-immobilization of heparin in chitosan scaffolds could enhance the stability of subsequently loaded NGF. The NGF loaded heparin/chitosan scaffolds could obviously improve the attachment and proliferation of Schwann cells in vitro. More importantly, the NGF loaded heparin/chitosan scaffolds could effectively promote the morphology development of Schwann cells. The study may provide a useful experimental basis to design and develop artificial implants for peripheral nerve regeneration and other tissue regeneration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Reliability Analysis of Jacket Platforms in Malaysia-Environmental Load Factors

    Directory of Open Access Journals (Sweden)

    Nelson J. Cossa

    2012-09-01

    Full Text Available In recent years, there has been a significant trend for adoption of the ISO-19902 standards for design of fixed steel offshore structures. The implementation of this standard aims to provide a harmonized international framework of design. Unlike, the traditional and currently used, WSD-method, the ISO-19902, follows the LRFD-method, that consists of both partial load and resistance factors. These partial factors are usually calibrated through reliability analysis. In these analyses, the performance of a structure is defined by the limit state function for the critical mode of failure. This paper, focuses mainly on the ultimate (strength limit state which is directly related to the (highest environmental loading. The partial environmental load factors contained in the ISO 19902, were calibrated for the Gulf of Mexico and UK's North Sea conditions, which are relatively harsh than those in Malaysia. The study presents the steps taken for the determination of the environmental load factor for tubular members of jacket platforms in Malaysia. The factor was determined such that the reliability of tubular members of jacket designed as per the LRFD-method is at the level of target reliability obtained by the WSD-method.

  1. Bearing Capacity Factors for Eccentrically Loaded Strip Footings Using Variational Analysis

    Directory of Open Access Journals (Sweden)

    Xinggao Li

    2013-01-01

    Full Text Available Bearing capacity factors for eccentrically loaded strip smooth footings on homogenous cohesive frictional material are deduced by the variational limit equilibrium method and by assuming general shear failure along continuous curved slip surface. From the calculated results, the effective width rule suggested by Meyerhof for bearing capacity factors due to cohesion of soil is justified, and the superposition principle of bearing capacity for eccentrically loaded strip smooth footings is derived together with the bearing capacity factors for cohesion and unit weight of soil. The two factors are represented by soil strength parameters and eccentricity of load. The bearing capacity factor related to unit weight for cohesionless soil is less than that for cohesive frictional soil. The reason for this discrepancy lies in the existence of the soil cohesion, for the shape of the critical rupture surface of footing soil depends on both soil strength parameters rather than on friction angle alone in the previous limit equilibrium solutions. The contact between footing and soil is decided by both the load and the mechanical properties of soil. Under conditions of higher eccentricity and less strength properties of soil, part of the footing will separate from the underlying soil.

  2. Modelling the impact of causal and non-causal factors on disruption duration for Toronto's subway system: An exploratory investigation using hazard modelling.

    Science.gov (United States)

    Louie, Jacob; Shalaby, Amer; Habib, Khandker Nurul

    2017-01-01

    Most investigations of incident-related delay duration in the transportation context are restricted to highway traffic, with little attention given to delays due to transit service disruptions. Studies of transit-based delay duration are also considerably less comprehensive than their highway counterparts with respect to examining the effects of non-causal variables on the delay duration. However, delays due to incidents in public transit service can have serious consequences on the overall urban transportation system due to the pivotal and vital role of public transit. The ability to predict the durations of various types of transit system incidents is indispensable for better management and mitigation of service disruptions. This paper presents a detailed investigation on incident delay durations in Toronto's subway system over the year 2013, focusing on the effects of the incidents' location and time, the train-type involved, and the non-adherence to proper recovery procedures. Accelerated Failure Time (AFT) hazard models are estimated to investigate the relationship between these factors and the resulting delay duration. The empirical investigation reveals that incident types that impact both safety and operations simultaneously generally have longer expected delays than incident types that impact either safety or operations alone. Incidents at interchange stations are cleared faster than incidents at non-interchange stations. Incidents during peak periods have nearly the same delay durations as off-peak incidents. The estimated models are believed to be useful tools in predicting the relative magnitude of incident delay duration for better management of subway operations.

  3. Factors Determining Disease Duration in Alzheimer’s Disease: A Postmortem Study of 103 Cases Using the Kaplan-Meier Estimator and Cox Regression

    Directory of Open Access Journals (Sweden)

    R. A. Armstrong

    2014-01-01

    Full Text Available Factors associated with duration of dementia in a consecutive series of 103 Alzheimer’s disease (AD cases were studied using the Kaplan-Meier estimator and Cox regression analysis (proportional hazard model. Mean disease duration was 7.1 years (range: 6 weeks–30 years, standard deviation = 5.18; 25% of cases died within four years, 50% within 6.9 years, and 75% within 10 years. Familial AD cases (FAD had a longer duration than sporadic cases (SAD, especially cases linked to presenilin (PSEN genes. No significant differences in duration were associated with age, sex, or apolipoprotein E (Apo E genotype. Duration was reduced in cases with arterial hypertension. Cox regression analysis suggested longer duration was associated with an earlier disease onset and increased senile plaque (SP and neurofibrillary tangle (NFT pathology in the orbital gyrus (OrG, CA1 sector of the hippocampus, and nucleus basalis of Meynert (NBM. The data suggest shorter disease duration in SAD and in cases with hypertensive comorbidity. In addition, degree of neuropathology did not influence survival, but spread of SP/NFT pathology into the frontal lobe, hippocampus, and basal forebrain was associated with longer disease duration.

  4. Factors associated with prolonged duration of post-tympanoplasty local treatment in adult chronic otitis media patients: A retrospective observational study using a Japanese inpatient database.

    Science.gov (United States)

    Suzuki, Sayaka; Yasunaga, Hideo; Matsui, Hiroki; Fushimi, Kiyohide; Yamasoba, Tatsuya

    2016-08-01

    The occurrence of persistent infection following tympanoplasty has been reported in many studies, and it is important to know the risks for site infection after tympanoplasty. In this study, we aimed to explore the factors affecting early wound complications after tympanoplasty for chronic otitis media. We conducted a retrospective cohort study using the Diagnosis Procedure Combination database. Data on a total of 13,094 adult patients from 420 acute-care hospitals who received tympanoplasty for chronic otitis media from 2010 to 2013 were extracted. The duration (days) of postsurgical local wound treatment was measured as an outcome, because this duration was assumed to be prolonged by the existence of wound infection. The associations between treatment duration and background characteristics (age, sex, body mass index, smoking status, diabetes mellitus, use of antithrombotic agents, with or without cholesteatoma, duration of anesthesia, academic hospital or not, and hospital volume) were assessed by multivariable linear regression analyses, fitted with a generalized estimating equation to adjust for within-hospital clustering. The median treatment duration in each hospital was 8 days (interquartile range: 7-11). Factors significantly associated with longer treatment duration were: older age (0.2 days for 10-year increase), use of antithrombotic agents during hospitalization (1.8 days), and prolonged duration of anesthesia (vs. otitis media. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  5. A cyclodissipativity characterization of power factor compensation of nonlinear loads under nonsinusoidal conditions

    NARCIS (Netherlands)

    del Puerto-Flores, D.; Ortega, R.; Scherpen, J. M. A.

    2012-01-01

    Recently, it has been established that power factor (PF) improvement for nonlinear loads with nonsinusoidal source voltage is equivalent to imposing the property of cyclodissipativity to the source terminals. Using this framework, the classical capacitor and inductor compensators were interpreted in

  6. General Factor Loadings and Specific Effects of the Differential Ability Scales, Second Edition Composites

    Science.gov (United States)

    Maynard, Jennifer L.; Floyd, Randy G.; Acklie, Teresa J.; Houston, Lawrence, III

    2011-01-01

    The purpose of this study was to investigate the "g" loadings and specific effects of the core and diagnostic composite scores from the Differential Abilities Scales, Second Edition (DAS-II; Elliott, 2007a). Scores from a subset of the DAS-II standardization sample for ages 3:6 to 17:11 were submitted to principal factor analysis. Four composites,…

  7. General Factor Loadings and Specific Effects of the Differential Ability Scales, Second Edition Composites

    Science.gov (United States)

    Maynard, Jennifer L.; Floyd, Randy G.; Acklie, Teresa J.; Houston, Lawrence, III

    2011-01-01

    The purpose of this study was to investigate the "g" loadings and specific effects of the core and diagnostic composite scores from the Differential Abilities Scales, Second Edition (DAS-II; Elliott, 2007a). Scores from a subset of the DAS-II standardization sample for ages 3:6 to 17:11 were submitted to principal factor analysis. Four…

  8. Assessment of the magnitude of geographical variations in the duration of non-work-related sickness absence by individual and contextual factors.

    Science.gov (United States)

    Torá-Rocamora, Isabel; Martínez, José Miguel; Gimeno, David; Alberti, Constança; Jardí, Josefina; Manzanera, Rafael; Benavides, Fernando G; Delclos, George

    2015-01-01

    To examine variation in the duration of non-work-related sickness absence (NWRSA) across geographical areas and the degree to which this variation can be explained by individual and/or contextual factors. All first NWRSA episodes ending in 2007 and 2010 were analyzed. Individual (diagnosis, age, sex) and contextual factors (healthcare resources, socioeconomic factors) were analyzed to assess how much of the geographical variation was explained by these factors. Median NWRSA durations in quartiles were mapped by counties in Catalonia. Multilevel Cox proportional hazard regression models with episodes nested within counties were fitted to quantify the magnitude of this variation. The proportional change in variance (PCV), median hazard ratios (MHR) and interquartile hazard ratios (IHR) were calculated. We found a geographical pattern in the duration of NWRSA, with longer duration in northwestern Catalonia. There was a small, but statistically significant, geographical variation in the duration of NWRSA, which mostly decreased after adjustment for individual factors in both women (PCV=34.98%, MHR=1.09, IHR=1.13 in 2007; PCV=34.68%, MHR=1.11, IHR=1.28 in 2010) and men (PCV=39.88%, MHR=1.10, IHR=1.27 in 2007; PCV=45.93%, MHR=1.10, IHR=1.25 in 2010); only in the case of women in 2010 was there a reduction in county-level variance due to contextual covariates (PCV=16.18%, MHR=1.12, IHR=1.32). County-level variation in the duration of NWRSA was small and was explained more by individual than by contextual variables. Knowledge of geographic differences in NWRSA duration is needed to plan specific programs and interventions to minimize these differences. Copyright © 2014 SESPAS. Published by Elsevier Espana. All rights reserved.

  9. Sleep duration and chronic diseases among U.S. adults age 45 years and older: evidence from the 2010 Behavioral Risk Factor Surveillance System.

    Science.gov (United States)

    Liu, Yong; Wheaton, Anne G; Chapman, Daniel P; Croft, Janet B

    2013-10-01

    To examine the effects of obesity and frequent mental distress (FMD) on the relationship of sleep duration with coronary heart disease (CHD), stroke, and diabetes. Cross-sectional study. Population-based surveillance. There were 54,269 adults age 45 y or older who completed the 2010 Behavioral Risk Factor Surveillance System survey in 14 states. Nearly one third (31.1% or an estimated 11.1 million) of respondents age 45 y and older reported being short sleepers (≤ 6 h), 64.8% being optimal sleepers (7-9 h), and 4.1% being long sleepers (≥ 10 h) in a 24-h period. Compared with the optimal sleep duration, both short and long sleep durations were significantly associated with obesity, FMD (mental health was not good ≥ 14 days during the past 30 days), CHD, stroke, and diabetes after controlling for sex, age, race/ethnicity, and education. The U-shaped relationships of sleep duration with CHD, stroke, and diabetes were moderately attenuated by FMD. The relationship between sleep duration and diabetes was slightly attenuated by obesity. Sleep duration had U-shaped relationships with leading chronic diseases. Further prospective studies are needed to determine how mental health and maintenance of a normal weight may interact with sleep duration to prevent chronic diseases.

  10. A New V2G Control Strategy for Load Factor Improvement Using Smoothing Technique

    Directory of Open Access Journals (Sweden)

    CHANHOM, P.

    2017-08-01

    Full Text Available This paper proposes a new vehicle-to-grid (V2G control strategy for improving the load factor in the power network. To operate the proposed strategy, the available storage capacity of the PEVs’ batteries is considered as a battery energy storage system (BESS for charging and discharging an amount of power corresponding to the V2G power command. Due to the remarkable advantages of the technique so-called simple moving average, it is selected for applying in the proposed V2G control strategy. In this research, for investigating the load factor improvement, the essential data including the daily-load profiles with 7-day and 14-day periods are used for the 3 studied cases. These 3 studied cases present the power network with variation of the PEVs locations for describing the PEVs usage and charging or discharging behavior. The performance of the proposed strategy is simulated and verified by the MATPOWER software. The simulation results show that the load factors of the 3 studied cases are improved. Moreover, the encouragement of energy arbitrage for the PEVs owners is also discussed in this paper.

  11. A cross-cultural comparison of sleep duration between U.S. and Australian adolescents: the effect of school start time, parent-set bedtimes and extracurricular load

    NARCIS (Netherlands)

    M.A. Short; M. Gradisar; L.C. Lack; H.R. Wright; J.F. Dewald; A.R. Wolfson; M.A. Carskadon

    2013-01-01

    Study Objective. To test whether sleep duration on school nights differs between adolescents in Australia and the United States and, if so, whether this difference is explained by cultural differences in school start time, parental involvement in setting bedtimes, and extracurricular commitments. Pa

  12. A cross-cultural comparison of sleep duration between U.S. and Australian adolescents: the effect of school start time, parent-set bedtimes and extracurricular load

    NARCIS (Netherlands)

    Short, M.A.; Gradisar, M.; Lack, L.C.; Wright, H.R.; Dewald, J.F.; Wolfson, A.R.; Carskadon, M.A.

    2013-01-01

    Study Objective. To test whether sleep duration on school nights differs between adolescents in Australia and the United States and, if so, whether this difference is explained by cultural differences in school start time, parental involvement in setting bedtimes, and extracurricular commitments.

  13. First Spanish version of the Memorial Delirium Assessment Scale: psychometric properties, responsiveness, and factor loadings.

    Science.gov (United States)

    Noguera, Antonio; Carvajal, Ana; Alonso-Babarro, Alberto; Chisholm, Gary; Bruera, Eduardo; Centeno, Carlos

    2014-01-01

    The Memorial Delirium Assessment Scale (MDAS) is a reliable and validated instrument with which to assess delirium. However, MDAS responsiveness has only been investigated in an indirect way. Also, neurobehavioral and global cognitive factors seem to be the MDAS main factor loads. The primary objective of this study was to evaluate MDAS responsiveness and analyze individual factors on this scale. The secondary objective was to confirm concurrent validity and reliability of the Spanish version of the MDAS. The translation-back translation method was used to obtain the Spanish version of the MDAS. Delirium diagnosis was determined by the clinical Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria and with the Confusion Assessment Method. Responsiveness and factor loadings were determined with the Delirium Rating Scale-Revised-98, the Mini-Mental State Examination (MMSE), and the MDAS at baseline (0 hours) and at 72 hours. Variation in the scores of the Delirium Rating Scale-Revised-98 shows a correlation of r = 0.93, with variation in MDAS scores at P < 0.001. Variation in MMSE scores shows a correlation of r = -0.84, with variation in MDAS scores at P = 0.015. Factor I, neurobehavioral (reduced awareness, reduced attention, perceptual disturbance, delusions, altered psychomotor activity, and sleep-wake cycle disturbance), correlated moderately with the MMSE at -0.56. Factor II, global cognitive (disorientation, short-term memory impairment, impaired digit span, and disorganized thinking), correlated strongly with the MMSE at -0.81. Factor II was significantly more reliable than Factor I, rho = 0.7, P = 0.01. The high responsiveness confirms the value of the MDAS for ongoing delirium assessment. Two differentiated factor loadings point to a potential future need for MDAS subscales. Copyright © 2014 U.S. Cancer Pain Relief Committee. All rights reserved.

  14. Relationship between Serum Transforming Growth Factor β1 Concentrations and the Duration of Type 1 Diabetes Mellitus in Children and Adolescents

    Directory of Open Access Journals (Sweden)

    Katarzyna Zorena

    2013-01-01

    Full Text Available The aim of this study was to evaluate the relationship between serum transforming growth factor β1 (TGF-β1 concentrations and the duration of type 1 diabetes mellitus (T1DM in children and adolescents. One hundred and sixteen patients with T1DM and 19 healthy controls were examined. Serum TGF-β1 concentrations were measured using the cytometric bead array (CBA. A positive association between the time of diabetes duration and higher serum TGF-β1 concentrations was observed. Similarly, the prevalence of microvascular complications, such as retinopathy and nephropathy, increased with the duration of diabetes. Logistic regression analysis showed that serum TGF-β1 concentrations and the duration of the disease are independent risk factors of microangiopathy development. Higher serum TGF-β1 concentrations were associated with a significant risk of microangiopathy development after 10 years of T1DM duration. In the successive years of the disease, the effect was even stronger. The results of our study indicate that serum TGF-β1 concentrations are one of the factors that may have an impact on the progression of vascular complications in children and adolescents with T1DM.

  15. Factors Controlling Sediment Load in The Central Anatolia Region of Turkey: Ankara River Basin.

    Science.gov (United States)

    Duru, Umit; Wohl, Ellen; Ahmadi, Mehdi

    2017-01-18

    Better understanding of the factors controlling sediment load at a catchment scale can facilitate estimation of soil erosion and sediment transport rates. The research summarized here enhances understanding of correlations between potential control variables on suspended sediment loads. The Soil and Water Assessment Tool was used to simulate flow and sediment at the Ankara River basin. Multivariable regression analysis and principal component analysis were then performed between sediment load and controlling variables. The physical variables were either directly derived from a Digital Elevation Model or from field maps or computed using established equations. Mean observed sediment rate is 6697 ton/year and mean sediment yield is 21 ton/y/km² from the gage. Soil and Water Assessment Tool satisfactorily simulated observed sediment load with Nash-Sutcliffe efficiency, relative error, and coefficient of determination (R²) values of 0.81, -1.55, and 0.93, respectively in the catchment. Therefore, parameter values from the physically based model were applied to the multivariable regression analysis as well as principal component analysis. The results indicate that stream flow, drainage area, and channel width explain most of the variability in sediment load among the catchments. The implications of the results, efficient siltation management practices in the catchment should be performed to stream flow, drainage area, and channel width.

  16. Factors Controlling Sediment Load in The Central Anatolia Region of Turkey: Ankara River Basin

    Science.gov (United States)

    Duru, Umit; Wohl, Ellen; Ahmadi, Mehdi

    2017-05-01

    Better understanding of the factors controlling sediment load at a catchment scale can facilitate estimation of soil erosion and sediment transport rates. The research summarized here enhances understanding of correlations between potential control variables on suspended sediment loads. The Soil and Water Assessment Tool was used to simulate flow and sediment at the Ankara River basin. Multivariable regression analysis and principal component analysis were then performed between sediment load and controlling variables. The physical variables were either directly derived from a Digital Elevation Model or from field maps or computed using established equations. Mean observed sediment rate is 6697 ton/year and mean sediment yield is 21 ton/y/km² from the gage. Soil and Water Assessment Tool satisfactorily simulated observed sediment load with Nash-Sutcliffe efficiency, relative error, and coefficient of determination ( R²) values of 0.81, -1.55, and 0.93, respectively in the catchment. Therefore, parameter values from the physically based model were applied to the multivariable regression analysis as well as principal component analysis. The results indicate that stream flow, drainage area, and channel width explain most of the variability in sediment load among the catchments. The implications of the results, efficient siltation management practices in the catchment should be performed to stream flow, drainage area, and channel width.

  17. Prevalence and duration of breastfeeding during the first six months of life: factors affecting an early cessation

    Directory of Open Access Journals (Sweden)

    F. Garbarino

    2013-10-01

    Full Text Available OBJECTIVES: to assess the mean duration, prevalence and reasons that lead to an early cessation of breastfeeding in a group of healthy term infants in the first six months of life. METHODS: prospective, observational study. One-hundred Caucasian, non smoking mothers, that intended to breastfeed for at least 12 weeks, were enrolled. Information on anthropometric parameters, type of delivery, socio-demographic characteristics, mode of feeding and reasons for stopping breastfeeding have been obtained through three different questionnaires (submitted at enrollment, on the 7th day, at 1, 2, 3 and 6 months. RESULTS: exclusive breastfeeding gradually decreased from the 7th day to the 6th month of life. Most of the mothers stopped breastfeeding during the first month and a half or after 3 months and a half. Two percent of the mothers stopped on the 7th day whereas at 6 months the percentage of cessation was 14%. The cumulative percentage of interruption at 6th month was 45%. Maternal factors, like sore nipples or delayed onset of lactation, were the most frequent reasons that led to an early cessation, while during the following months inadequate breast milk and latch-on problems were predominant. On the other hand, attending a pre-natal course or having a previous successful breastfeeding experience were significantly associated with a long-lasting breastfeeding. CONCLUSIONS: promotion of breastfeeding during the prenatal course and a better support for lactation management during the first months seem to be the areas where more efforts are needed to implement breastfeeding rates.

  18. In Situ Loading of Basic Fibroblast Growth Factor Within Porous Silica Nanoparticles for a Prolonged Release

    Directory of Open Access Journals (Sweden)

    Postovit Lynne-Marie

    2009-01-01

    Full Text Available Abstract Basic fibroblast growth factor (bFGF, a protein, plays a key role in wound healing and blood vessel regeneration. However, bFGF is easily degraded in biologic systems. Mesoporous silica nanoparticles (MSNs with well-tailored porous structure have been used for hosting guest molecules for drug delivery. Here, we report an in situ route to load bFGF in MSNs for a prolonged release. The average diameter (d of bFGF-loaded MSNs is 57 ± 8 nm produced by a water-in-oil microemulsion method. The in vitro releasing profile of bFGF from MSNs in phosphate buffer saline has been monitored for 20 days through a colorimetric enzyme linked immunosorbent assay. The loading efficiency of bFGF in MSNs is estimated at 72.5 ± 3%. In addition, the cytotoxicity test indicates that the MSNs are not toxic, even at a concentration of 50 μg/mL. It is expected that the in situ loading method makes the MSNs a new delivery system to deliver protein drugs, e.g. growth factors, to help blood vessel regeneration and potentiate greater angiogenesis.

  19. Spectral density estimation of European airlines load factors for Europe-Middle East and Europe-Far East flights

    National Research Council Canada - National Science Library

    Tesfay, Yohannes Yebabe; Solibakke, Per Bjarte

    2015-01-01

    .... The load factor is a metric that measures the airline’s capacity and demand management. This paper aimed to identify serial and periodic autocorrelation on the load factors of the Europe-Mid East and Europe-Far East airline flights...

  20. Assessment of vehicular live load and load factors for design of short-span bridges according to the new Egyptian Code

    Directory of Open Access Journals (Sweden)

    Hatem M. Seliem

    2015-04-01

    The study shows that concrete box-girders designed according to ECP-201:2012 and ECP-201:2003 using the ultimate limit state method yield almost the same demand. Despite the increase in the VLL of ECP-201:2012, and consequently the live load forces, concrete I-shaped girder bridges will be subjected to less total factored internal forces in comparison to ECP-201:2003 This is attributed to the interaction between the live to dead loads ratio and the load combinations. Design of composite steel plate girder bridges according to ECP-201:2012 using the allowable stress design method yields over designed sections.

  1. Surface water acidification and critical loads: exploring the F-factor

    Directory of Open Access Journals (Sweden)

    K. Bishop

    2009-11-01

    Full Text Available As acid deposition decreases, uncertainties in methods for calculating critical loads become more important when judgements have to be made about whether or not further emission reductions are needed. An important aspect of one type of model that has been used to calculate surface water critical loads is the empirical F-factor which estimates the degree to which acid deposition is neutralised before it reaches a lake at any particular point in time relative to the pre-industrial, steady-state water chemistry conditions.

    In this paper we will examine how well the empirical F-functions are able to estimate pre-industrial lake chemistry as lake chemistry changes during different phases of acidification and recovery. To accomplish this, we use the dynamic, process-oriented biogeochemical model SAFE to generate a plausible time series of annual runoff chemistry for ca. 140 Swedish catchments between 1800 and 2100. These annual hydrochemistry data are then used to generate empirical F-factors that are compared to the "actual" F-factor seen in the SAFE data for each lake and year in the time series. The dynamics of the F-factor as catchments acidify, and then recover are not widely recognised.

    Our results suggest that the F-factor approach worked best during the acidification phase when soil processes buffer incoming acidity. However, the empirical functions for estimating F from contemporary lake chemistry are not well suited to the recovery phase when the F-factor turns negative due to recovery processes in the soil. This happens when acid deposition has depleted the soil store of BC, and then acid deposition declines, reducing the leaching of base cations to levels below those in the pre-industrial era. An estimate of critical load from water chemistry during recovery and empirical F functions would therefore result in critical loads that are too low. Therefore, the empirical estimates of the F-factor are a significant source of

  2. Surface water acidification and critical loads: exploring the F-factor

    Directory of Open Access Journals (Sweden)

    L. Rapp

    2009-05-01

    Full Text Available As acid deposition decreases, uncertainties in methods for calculating critical loads become more important when judgements have to be made about whether or not further emission reductions are needed. An important aspect of one type of model that has been used to calculate surface water critical loads is the empirical F-factor which estimates the degree to which acid deposition is neutralised before it reaches a lake at any particular point in time relative to the pre-industrial, steady-state water chemistry conditions.

    In this paper we will examine how well the empirical F-functions are able to estimate pre-industrial lake chemistry as lake chemistry changes during different phases of acidification and recovery. To accomplish this, we use the dynamic, process-oriented biogeochemical model SAFE to generate a plausible time series of annual runoff chemistry for ca 140 Swedish catchments between 1800 and 2100. These annual hydrochemistry data are then used to generate empirical F-factors that are compared to the "actual" F-factor seen in the SAFE data for each lake and year in the time series. The dynamics of the F-factor as catchments acidify, and then recover are not widely recognised.

    Our results suggest that the F-factor approach worked best during the acidification phase when soil processes buffer incoming acidity. However, the empirical functions for estimating F from contemporary lake chemistry are not well suited to the recovery phase when the F-factor turns negative due to recovery processes in the soil. Therefore, the empirical estimates of the F-factor are a significant source of uncertainty in the estimate of surface water critical loads and related calculations for quantifying lake acidification status, especially now that acid deposition has declined across large areas of Europe and North America.

  3. The Transport Properties of Concrete under the Simultaneous Coupling of Fatigue Load and Environment Factors

    Institute of Scientific and Technical Information of China (English)

    WANG Caihui; SUN Wei; JING Jinyang; HAN Jiande; RONG Hui

    2012-01-01

    A set of coupling experimental instrument was designed to study the transport properties of chloride ion in concrete under simultaneous coupling action of fatigue load and environmental factors.Firstly the water-saturated performance of modern concrete was investigated,then diffusion performance of chloride ion under different stress levels and different temperature were studied respectively; meanwhile,the timedependent behavior of the chloride ion diffusion in concrete was also researched.The results showed that the saturation degree of concrete can reach as high as 99%.Besides,diffusion coefficient of chloride ion increased with increasing of the stress level and temperature,and when the stress level and temperature are at 0.6 and 60 ℃ respectively,the diffusion coefficient is 6.3 × 10 14 m2/s,moreover the diffusion coefficient of chloride ion in concrete decreased with time under the simultaneous coupling action of fatigue load and environment factors.

  4. Parametric Equation of Stress Concentration Factor for Circular X-Joints Under Axial Loads

    Institute of Scientific and Technical Information of China (English)

    QU Shu-ying; ZHANG Guo-dong; ZHANG Bao-feng; WANG Xin-jian

    2007-01-01

    In engineering practice,tubular X-joints have been widely used in offshore structures.The fatigue failure of tubular X-joints in offshore engineering is mainly caused by axial tensile stress.In this study,the stress concentration factor distribution along the weld toe in the hot spot stress region for tubular X-joints subject to axial loads have been analyzed by use of finite element method.Through numerical analysis,it has been found that the peak stress concentration factor is located at the saddle position.Thereafter,80 models have been analyzed,and the effect of the geometric parameters of a tubular X-joint on the stress concentration factor has been investigated.Based on the experimental values of the numerical stress concentration factor,a parametric equation to calculate the stress concentration factor of tubular X-joints has been proposed.The accuracy of this equation has been verified against the requirement of the Fatigue Guidance Review Panel,and the proposed equation is found capable of producing reasonably accurate stress concentration factor values for tubular X-joints subject to axial loads.

  5. Relative importance of multiple factors on terrestrial loading of DOC to Arctic river networks

    Energy Technology Data Exchange (ETDEWEB)

    Kicklighter, David W. [Ecosystem Center, The; Hayes, Daniel J [ORNL; Mcclelland, James W [University of Texas; Peterson, Bruce [Marine Biological Laboratory; Mcguire, David [University of Alaska; Melillo, Jerry [Marine Biological Laboratory

    2014-01-01

    Terrestrial carbon dynamics influence the contribution of dissolved organic carbon (DOC) to river networks in addition to controlling carbon fluxes between the land surface and the atmosphere. In this study, we use a biogeochemical process model to simulate the lateral transfer of DOC from land to the Arctic Ocean via riverine transport. We estimate that the pan-arctic watershed has contributed, on average, 32 Tg C/yr of DOC to the Arctic Ocean over the 20th century with most coming from the extensive area of boreal deciduous needle-leaved forests and forested wetlands in Eurasian watersheds. We also estimate that the rate of terrestrial DOC loading has been increasing by 0.037 Tg C/yr2 over the 20th century primarily as a result of increases in air temperatures and precipitation. These increases have been partially compensated by decreases in terrestrial DOC loading caused by wildfires. Other environmental factors (CO2 fertilization, ozone pollution, atmospheric nitrogen deposition, timber harvest, agriculture) are estimated to have relatively small effects on terrestrial DOC loading to arctic rivers. The effects of the various environmental factors on terrestrial carbon dynamics have both compensated and enhanced concurrent effects on hydrology to influence terrestrial DOC loading. Future increases in riverine DOC concentrations and export may occur from warming-induced increases in terrestrial DOC production associated with enhanced microbial metabolism and the exposure of additional organic matter from permafrost degradation along with decreases in water yield associated with warming-induced increases in evapotranspiration. Improvements in simulating terrestrial DOC loading to pan-arctic rivers in the future will require better information on the spatial distribution of precipitation and its temporal trends, carbon dynamics of larch-dominated ecosystems in eastern Siberia, and the role of industrial organic effluents on carbon budgets of rivers in western

  6. Interglacial Durations

    Science.gov (United States)

    Mangili, Clara; McManus, Jerry F.; Raynaud, Dominique

    2014-05-01

    In the context of future global warming induced by human activities, it is essential to assess the role of natural climatic variations. Precise knowledge of the duration of past interglacial periods is fundamental to the understanding of the potential future evolution of the Holocene. Past ice age cycles provide a natural laboratory for exploring the progression and duration of interglacial climate. Palaeorecords from ice, land and oceans extend over the last 800 ka, revealing eight glacial-interglacial cycles, with a range of insolation and greenhouse gas influences. The interglacials display a correspondingly large variety of intensity and duration, thus providing an opportunity for major insights into the mechanisms involved in the behaviour of interglacial climates. A comparison of the duration of these interglacials, however, is often difficult, as the definition of an interglacial depends on the archive that is considered. Therefore, to compare interglacial length and climate conditions from different archives, a consistent definition of interglacial conditions is required, ideally one that is not bound to the method nor to the archive under consideration. Here we present a method to identify interglacials and to calculate their length by mean of a simple statistical approach. We based our method on ~ 400 ka windows of time to determine mean climatic conditions while allowing for the possibility of long term evolution of the climatic baseline. For our study of interglacials of the past 800 ka, we used two windows that largely align with the pre- (800-430 ka ago) and post- (430-0 ka ago) mid-Brunhes event (MBE), although the resulting conclusions are not sensitive to this particular division. We applied this method to the last 800 ka of a few palaeoclimate records: the deuterium ice core (EDC) record as a climatic proxy, the benthic δ18O stack (LR04) as a proxy for sea level/ice volume, ice core (Vostok, EDC) atmospheric CO2 and additional records. Although

  7. Sufficient sleep duration contributes to lower cardiovascular disease risk in addition to four traditional lifestyle factors: the MORGEN study

    NARCIS (Netherlands)

    Hoevenaar-Blom, M.P.; Spijkerman, A.M.W.; Kromhout, D.; Verschuren, W.M.M.

    2014-01-01

    Background The contribution of sufficient sleep duration to lower CVD risk in addition to sufficient physical activity, a healthy diet, (moderate) alcohol consumption, and non-smoking has not been investigated yet. Design The MORGEN study is a prospective cohort study including 8128 men and 9759

  8. Sufficient sleep duration contributes to lower cardiovascular disease risk in addition to four traditional lifestyle factors: the MORGEN study

    NARCIS (Netherlands)

    Hoevenaar-Blom, M.P.; Spijkerman, A.M.W.; Kromhout, D.; Verschuren, W.M.M.

    2014-01-01

    Background The contribution of sufficient sleep duration to lower CVD risk in addition to sufficient physical activity, a healthy diet, (moderate) alcohol consumption, and non-smoking has not been investigated yet. Design The MORGEN study is a prospective cohort study including 8128 men and 9759 wom

  9. Observation of the Mating Behavior of Honey Bee (Apis mellifera L.) Queens Using Radio-Frequency Identification (RFID): Factors Influencing the Duration and Frequency of Nuptial Flights.

    Science.gov (United States)

    Heidinger, Ina Monika Margret; Meixner, Marina Doris; Berg, Stefan; Büchler, Ralph

    2014-07-01

    We used radio-frequency identification (RFID) to record the duration and frequency of nuptial flights of honey bee queens (Apis mellifera carnica) at two mainland mating apiaries. We investigated the effect of a number of factors on flight duration and frequency: mating apiary, number of drone colonies, queen's age and temperature. We found significant differences between the two locations concerning the number of flights on the first three days. We also observed an effect of the ambient temperature, with queens flying less often but longer at high temperatures compared to lower temperatures. Increasing the number of drone colonies from 33 to 80 colonies had no effect on the duration or on the frequency of nuptial flights. Since our results agree well with the results of previous studies, we suggest RFID as an appropriate tool to investigate the mating behavior of honey bee queens.

  10. Observation of the Mating Behavior of Honey Bee (Apis mellifera L. Queens Using Radio-Frequency Identification (RFID: Factors Influencing the Duration and Frequency of Nuptial Flights

    Directory of Open Access Journals (Sweden)

    Ina Monika Margret Heidinger

    2014-07-01

    Full Text Available We used radio-frequency identification (RFID to record the duration and frequency of nuptial flights of honey bee queens (Apis mellifera carnica at two mainland mating apiaries. We investigated the effect of a number of factors on flight duration and frequency: mating apiary, number of drone colonies, queen’s age and temperature. We found significant differences between the two locations concerning the number of flights on the first three days. We also observed an effect of the ambient temperature, with queens flying less often but longer at high temperatures compared to lower temperatures. Increasing the number of drone colonies from 33 to 80 colonies had no effect on the duration or on the frequency of nuptial flights. Since our results agree well with the results of previous studies, we suggest RFID as an appropriate tool to investigate the mating behavior of honey bee queens.

  11. Stress intensity factor and load transfer analysis of a cracked riveted lap joint

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, P.M.G.P. [DEMEGI, Faculdade de Engenharia, Universidade do Porto, 4200-465 Porto (Portugal)]. E-mail: pmgpm@fe.up.pt; Matos, P.F.P. de [DEMEGI, Faculdade de Engenharia, Universidade do Porto, 4200-465 Porto (Portugal); Camanho, P.P. [DEMEGI, Faculdade de Engenharia, Universidade do Porto, 4200-465 Porto (Portugal); Pastrama, Stefan D. [Department of Strength of Materials, University Politehnica of Bucharest, Splaiul Independentei nr. 313, Sector 6, Bucharest (Romania); Castro, P.M.S.T. de [DEMEGI, Faculdade de Engenharia, Universidade do Porto, 4200-465 Porto (Portugal)

    2007-07-01

    One of the main problems of aeronautical structures is the onset and growth of defects due to fatigue loading. This phenomenon is accentuated in areas of stress concentration, for example in the connection of components, such as the riveted joints of fuselage panels. Several geometric configurations can be used in riveted joints of fuselage panels. This work is focused on one geometry, a single-lap splice with three rivets rows and one rivet column. A three-dimensional stress analysis using the finite element method was carried out in order to analyze the load transfer as a function of crack geometry and length, and to determine the stress intensity factors for one or two cracks emanating from the edge of the hole located at the critical cross section.

  12. Enhancement of effective electromechanical coupling factor by mass loading in layered surface acoustic wave device structures

    Science.gov (United States)

    Tang, Gongbin; Han, Tao; Teshigahara, Akihiko; Iwaki, Takao; Hashimoto, Ken-ya

    2016-07-01

    This paper describes a drastic enhancement of the effective coupling factor K\\text{e}2 by mass loading in layered surface acoustic wave (SAW) device structures such as the ScAlN film/Si substrate structure. This phenomenon occurs when the piezoelectric layer exhibits a high acoustic wave velocity. The mass loading decreases the SAW velocity and causes SAW energy confinement close to the top surface where an interdigital transducer is placed. It is shown that this phenomenon is obvious even when an amorphous SiO2 film is deposited on the top surface for temperature compensation. This K\\text{e}2 enhancement was also found in various combinations of electrode, piezoelectric layer, and/or substrate materials. The existence of this phenomenon was verified experimentally using the ScAlN film/Si substrate structure.

  13. Factors affecting the duration of nestling period and fledging order in Tengmalm's owl (Aegolius funereus): effect of wing length and hatching sequence.

    Science.gov (United States)

    Kouba, Marek; Bartoš, Luděk; Korpimäki, Erkki; Zárybnická, Markéta

    2015-01-01

    In altricial birds, the nestling period is an important part of the breeding phase because the juveniles may spend quite a long time in the nest, with associated high energy costs for the parents. The length of the nestling period can be variable and its duration may be influenced by both biotic and abiotic factors; however, studies of this have mostly been undertaken on passerine birds. We studied individual duration of nestling period of 98 Tengmalm's owl chicks (Aegolius funereus) at 27 nests during five breeding seasons using a camera and chip system and radio-telemetry. We found the nestlings stayed in the nest box for 27 - 38 days from hatching (mean ± SD, 32.4 ± 2.2 days). The individual duration of nestling period was negatively related to wing length, but no formally significant effect was found for body weight, sex, prey availability and/or weather conditions. The fledging sequence of individual nestlings was primarily related to hatching order; no relationship with wing length and/or other factors was found in this case. We suggest the length of wing is the most important measure of body condition and individual quality in Tengmalm's owl young determining the duration of the nestling period. Other differences from passerines (e.g., the lack of effect of weather or prey availability on nestling period) are considered likely to be due to different life-history traits, in particular different food habits and nesting sites and greater risk of nest predation among passerines.

  14. Study on changes in bed characteristics and friction factor in the presence of wash load in suspension

    Institute of Scientific and Technical Information of China (English)

    N K KHULLAR; Jaspal SINGH

    2014-01-01

    Results of an experimental study on the effects of different concentrations of wash load on the size of bed features and resistance to flow in a laboratory flume are presented. The experiments were carried out under different hydraulic conditions in a 30 m long, 0.204 m wide and 0.5 m deep tilting flume under clear water condition and in the presence of different concentration of wash load in the flow. The bed material used consisted of uniform sediment of size 0.96 mm. Analysis of the data indicates that the characteristics of the bed features change and friction factor increases in the presence of different concentration of wash load in the flow. The reasons for changes in the characteristics of the bed features and increase in friction factor in the presence of wash load are identified and a relationship for predicting friction factor in the presence of wash load has been established.

  15. Investigation of the Orthodontic Loading the Timing and Duration of the Prognosis of the Autologous Transplant Periodontal Repair%正畸加载时机和持续时间对自体移植牙牙周修复预后的影响

    Institute of Scientific and Technical Information of China (English)

    李尚峰

    2013-01-01

    Objective:To investigate the orthodontic loading the timing and duration of the prognosis of the autologous transplant periodontal repair. Methods: 12 beagle dogs were randomly divided into four groups ( n = 3 ) , each dog choose four first premolars autologous transplantation , respectively, in the autogenous teeth transplantation 2,4,8 and 12 weeks after the surgery the orthodontic load duration of 4 weeks, their first premolar periodontal tissue research , detection of root resorption rate analysis of periodontal tissue recovery . Results:the experimental group the orthodontic loaded autologous transplantation tooth root absorption rate significantly lower than the control group without orthodontic loaded autologous transplantation tooth root absorption rate, the difference was significant , statistically significant , the different loading timing and duration of autologous transplantation tooth root absorption rate was no significant difference not statistically significant , but two factor interaction . Conclusion:The orthodontic force loading can effectively improve the autologous transplant tooth root absorption status and periodontal tissue, but the orthodontic load time and duration of the impact on the autologous transplantation teeth absorption rate is not obvious enough ,Most obvious effect for two weeks on improving autologous transplantation periodontal tissue to orthodontic loading from extracted teeth 4 weeks after transplantation .%  目的:探讨正畸加载时机和持续时间对自体移植牙牙周修复预后的影响。方法:选择12只比格犬,随机分为4组,每组3只,每犬选择4颗第1前磨牙进行自体移植,分别于自体牙移植手术后的第2、4、8、12周进行正畸加载,持续时间分别为1、2、4周,对其第1前磨牙牙周组织进行研究,检测牙根吸收率,分析其牙周组织的恢复情况。结果:实验组正畸加载自体移植牙牙根吸收率明显低于对照组无正

  16. Predictive factors of adherence to frequency and duration components in home exercise programs for neck and low back pain: an observational study

    Directory of Open Access Journals (Sweden)

    Jimeno-Serrano Francisco J

    2009-12-01

    Full Text Available Abstract Background Evidence suggests that to facilitate physical activity sedentary people may adhere to one component of exercise prescriptions (intensity, duration or frequency without adhering to other components. Some experts have provided evidence for determinants of adherence to different components among healthy people. However, our understanding remains scarce in this area for patients with neck or low back pain. The aims of this study are to determine whether patients with neck or low back pain have different rates of adherence to exercise components of frequency per week and duration per session when prescribed with a home exercise program, and to identify if adherence to both exercise components have distinct predictive factors. Methods A cohort of one hundred eighty-four patients with chronic neck or low back pain who attended physiotherapy in eight primary care centers were studied prospectively one month after intervention. The study had three measurement periods: at baseline (measuring characteristics of patients and pain, at the end of physiotherapy intervention (measuring characteristics of the home exercise program and a month later (measuring professional behaviors during clinical encounters, environmental factors and self-efficacy, and adherence behavior. Results Adherence to duration per session (70.9% ± 7.1 was more probable than adherence to frequency per week (60.7% ± 7.0. Self-efficacy was a relevant factor for both exercise components (p Conclusion We have shown in a clinic-based study that adherence to exercise prescription frequency and duration components have distinct levels and predictive factors. We recommend additional study, and advise that differential attention be given in clinical practice to each exercise component for improving adherence.

  17. Expression of insulin-like growth factor I, insulin-like growth factor binding proteins, and collagen mRNA in mechanically loaded plantaris tendon

    DEFF Research Database (Denmark)

    Olesen, Jens L; Heinemeier, Katja M; Haddad, Fadia

    2006-01-01

    because they both are produced in fibroblast; however, the response of IGFBP-4 and -5 to mechanical loading and their role in IGF-I regulation in tendinous tissue are unknown. A splice variant of IGF-I, mechano-growth factor (MGF) is upregulated and known to be important for adaptation in loaded muscle...

  18. Predeployment Sleep Duration and Insomnia Symptoms as Risk Factors for New-Onset Mental Health Disorders Following Military Deployment

    Science.gov (United States)

    2013-01-01

    SLEEP, Vol. 36, No. 7, 2013 1011 Effects of Predeployment Sleep on Mental Health—Gehrman et al ployed, and the physical abuse item has the most...1998;155: 929 -33. 49. Chen MC, Burley HW, Gotlib IH. Reduced sleep quality in healthy girls at risk for depression. J Sleep Res 2012;21:68-72. 50. Gangwisch...Insomnia with ob- jective short sleep duration and incident hypertension: The Penn State Cohort. Hypertension 2012;60: 929 -35. 53. Vgontzas AN, Liao D

  19. The effects of a simple intervention on exposures to low back pain risk factors during traditional posterior load carriage.

    Science.gov (United States)

    Muslim, Khoirul; Nussbaum, Maury A

    2017-03-01

    Traditional posterior load carriage (PLC), typically performed without the use of an assistive device, is associated with a high prevalence of low back pain (LBP). However, there are few studies that have evaluated potential interventions to reduce exposures to LBP risk factors. This work examined the effects of a simple, potentially low-cost intervention using an assistive device (i.e., carrying aid) on exposures to factors related to LBP risk during PLC. Torso kinematics and kinetics, slip risk, and ratings of perceived discomfort (RPD) were obtained during simulated PLC on a walkway. Consistent with earlier results, increasing load mass substantially increased torso flexion and lumbosacral flexion moment, as well as RPDs in all anatomical regions evaluated. Using the carrying aid with a higher load placement resulted in substantially lower mean lumbosacral moments when carrying the heaviest load. In contrast, using the carrying aid with a lower load placement resulted in substantially higher torso flexion angles, higher mean lumbosacral moments when carrying heavier loads, and higher peak lumbosacral moments across all load masses. With use of the carrying aid, both higher and lower load placement resulted in significantly lower RPDs in the elbows and hands compared to the control condition. In summary, use of a carrying aid with higher load placement may be beneficial in reducing the risk of LBP during PLC. Future studies are needed, though, to improve the device design and to enhance external validity.

  20. Joint longitudinal hurdle and time-to-event models: an application related to viral load and duration of the first treatment regimen in patients with HIV initiating therapy.

    Science.gov (United States)

    Brilleman, Samuel L; Crowther, Michael J; May, Margaret T; Gompels, Mark; Abrams, Keith R

    2016-09-10

    Shared parameter joint models provide a framework under which a longitudinal response and a time to event can be modelled simultaneously. A common assumption in shared parameter joint models has been to assume that the longitudinal response is normally distributed. In this paper, we instead propose a joint model that incorporates a two-part 'hurdle' model for the longitudinal response, motivated in part by longitudinal response data that is subject to a detection limit. The first part of the hurdle model estimates the probability that the longitudinal response is observed above the detection limit, whilst the second part of the hurdle model estimates the mean of the response conditional on having exceeded the detection limit. The time-to-event outcome is modelled using a parametric proportional hazards model, assuming a Weibull baseline hazard. We propose a novel association structure whereby the current hazard of the event is assumed to be associated with the current combined (expected) outcome from the two parts of the hurdle model. We estimate our joint model under a Bayesian framework and provide code for fitting the model using the Bayesian software Stan. We use our model to estimate the association between HIV RNA viral load, which is subject to a lower detection limit, and the hazard of stopping or modifying treatment in patients with HIV initiating antiretroviral therapy. Copyright © 2016 John Wiley & Sons, Ltd.

  1. Basic fibroblast growth factor-loaded, mineralized biopolymer-nanofiber scaffold improves adhesion and proliferation of rat mesenchymal stem cells.

    Science.gov (United States)

    Kim, Tae-Hyun; Kim, Jung-Ju; Kim, Hae-Won

    2014-02-01

    Nanofibrous matrices are attractive scaffolding platforms for tissue regeneration. Modification of the nanofiber surface, particularly with biological proteins, improves cellular interactions. Here, we loaded basic fibroblast growth factor (bFGF) onto mineralized nanofibers and investigated the effect on adhesion and proliferation of rat mesenchymal stem cells. bFGF loading was significantly higher on the mineralized nanofiber than on the non-mineralized one. Release of bFGF from the mineralized nanofibers was continuous over 2 weeks. Cells cultured on the bFGF-loaded nanofiber attached and proliferated in significantly higher numbers than those on the bFGF-free nanofiber. bFGF-receptor inhibition study confirmed the biological role played by the loaded bFGF. This study details the advantages of the mineralized nanofiber surface for the loading and delivery bFGF, and thus the bFGF-loaded nanofiber scaffold may be useful for tissue repair and regeneration.

  2. Factors affecting the duration of native and second-language sentences produced in unspeeded and speeded conditions

    Science.gov (United States)

    Flege, James E.; Mackay, Ian R. A.

    2002-05-01

    The aim of this study was to provide insight into why non-natives generally produce longer second-language (L2) sentences than native speakers do. Four groups of 16 Italian-English bilinguals were recruited in Ottawa based on orthogonal differences in age of arrival (AOA) to Canada from Italy (early versus late) and self-reported percentage Italian use (low-L1 use versus high-L1 use). The bilinguals repeated duration-matched English and Italian sentences presented via a loudspeaker in an ``unspeeded'' condition, then as rapidly as possible (the ``speeded'' condition). The same effect of AOA was obtained in both conditions despite a 20% reduction in sentence duration in the speeded condition. That is, the early bilinguals produced significantly shorter English than Italian sentences, whereas the late bilinguals produced significantly longer English than Italian sentences. Different L1 use effects were obtained in the two conditions, however. In the unspeeded condition, the low-L1-use bilinguals produced shorter English than Italian sentences, with a nonsignificant effect of language for high-L1-use bilinguals. In the speeded condition, high-L1-use bilinguals produced shorter Italian than English sentences, with no language effect for the low-L1-use bilinguals. The underlying bases of AOA and L1 use effects on L2 sentence production will be discussed. [Work supported by NIH.

  3. Investigation of stress intensity factor for internal cracks in FG cylinders under static and dynamic loading

    Directory of Open Access Journals (Sweden)

    Mahmoud Shariati

    2017-01-01

    Full Text Available his paper investigates the variations of mode I stress intensity factor (KI for inner penny-shaped and circumferential cracks in functionally graded solid and hollow thick walled cylinders, respectively with the changes of crack geometry, material gradation and loading conditions. The functionally graded material of cylinders consists of epoxy and glass. It is assumed that the mechanical properties vary with a power law in the radial direction of cylinders. Micromechanical models for conventional composites are used to estimate the material properties of functionally graded cylinders. The equations of motion obtained from the extended finite element discretization are solved by the Newmark method in the time domain. The interaction integral method is employed to calculate the mode I stress intensity factor (KI. The MATLAB programming environment was implemented to solve the problem.

  4. Fatores associados com a duração do aleitamento materno Factors associated with duration of breastfeeding

    Directory of Open Access Journals (Sweden)

    Roberto G. Chaves

    2007-06-01

    used to study the duration of exclusive breastfeeding and of complementary feeding. The impact on breastfeeding duration of a series of co-variables was assessed by means of Cox regression modeling. RESULTS: The prevalence of exclusive breastfeeding at 6 months was 5.3%, and for breastfeeding at 12 months it was 33.7%. The median duration of exclusive breastfeeding was 40 days, and median breastfeeding duration was 237 days. Multivariate analysis demonstrated a negative association (p 9 consultations, use of alcohol or tobacco, delay before first feed (> 6 hours and use of a pacifier. CONCLUSIONS: Breastfeeding rates in Itaúna (MG are well below those recommended by the World Health Organization. The principal variables with a negative relationship with duration of exclusive breastfeeding and of complementary feeding are related to mother and baby health care and, therefore, interventions are possible.

  5. An application to calculate the factors which are used to determine the tensile rupture load of a lug under axial, transverse or oblique loading

    Directory of Open Access Journals (Sweden)

    Nicolae APOSTOLESCU

    2013-03-01

    Full Text Available This work describes a computer application to calculate the values of the factors which are used to determine the tensile rupture load of a lug under axial, transverse or oblique loading. It can be used as a procedure for identifying potential failure modes. Lugs are connector-type elements widely used as structural supports for pin connections in aerospace industry. Failure modes in lugs are functions of lug geometry and material mechanical properties. For a lug under axial load three modes of lug failure are considered: tension, shear and bearing. Under transverse load the load to cause rupture or unacceptable permanent deformation of the lug is given. Tension mode failure usually occurs in materials of low ductility. In materials with high ductility, the failure mode of a lug can be either tensile or shear tear-out, depending on the lug geometry. The application has a graphical interface that allows the user to use them with much ease and view immediately the results and provides a flexible ad-hoc print reports and diagrams that allow to present analysis information. It includes Microsoft Excel Object Library as reference to the Excel material properties file.

  6. Preliminary report on social psychological factors in long duration space flights: Review and directions for future research

    Science.gov (United States)

    Harrison, A. A.

    1978-01-01

    Group dynamics, sociological and psychological factors are examined. Crew composition and compatibility are studied. Group dynamics analysis includes: leadership; cohesiveness; conformity; and conflict.

  7. Protein growth factors loaded highly porous chitosan scaffold: A comparison of bone healing properties

    Energy Technology Data Exchange (ETDEWEB)

    Nandi, Samit K., E-mail: samitnandi1967@gmail.com [Department of Veterinary Surgery and Radiology, West Bengal University of Animal and Fishery Sciences, Kolkata (India); Kundu, Biswanath, E-mail: biswa_kundu@rediffmail.com [Bioceramics and Coating Division, CSIR—Central Glass and Ceramic Research Institute, Kolkata (India); Basu, Debabrata [Bioceramics and Coating Division, CSIR—Central Glass and Ceramic Research Institute, Kolkata (India)

    2013-04-01

    Present study aimed to investigate and compare effectiveness of porous chitosan alone and in combination with insulin like growth factor-1 (IGF-1) and bone morphogenetic protein-2 (BMP-2) in bone healing. Highly porous (85 ± 2%) with wide distribution of macroporous (70–900 μm) chitosan scaffolds were fabricated as bone substitutes by employing a simple liquid hardening method using 2% (w/v) chitosan suspension. IGF-1 and BMP-2 were infiltrated using vacuum infiltration with freeze drying method. Adsorption efficiency was found to be 87 ± 2 and 90 ± 2% for BMP-2 and IGF-1 respectively. After thorough material characterization (pore details, FTIR and SEM), samples were used for subsequent in vivo animal trial. Eighteen rabbit models were used to evaluate and compare control (chitosan) (group A), chitosan with IGF-1 (group B) and chitosan with BMP-2 (group C) in the repair of critical size bone defect in tibia. Radiologically, there was evidence of radiodensity in defect area from 60th day (initiated on 30th day) in groups B and C as compared to group A and attaining nearly bony density in most of the part at day 90. Histological results depicted well developed osteoblastic proliferation around haversian canal along with proliferating fibroblast, vascularization and reticular network which was more pronounced in group B followed by groups C and A. Fluorochrome labeling and SEM studies in all groups showed similar outcome. Hence, porous chitosan alone and in combination with growth factors (GFs) can be successfully used for bone defect healing with slight advantage of IGF-1 in chitosan samples. - Highlights: ► Fabrication and characterization of porous chitosan with or without IGF-1 and BMP-2 ► Highly porous growth factor loaded chitosan studied in animal subjects for 3 months ► Parameters studied: histopathology, radiology and fluorochrome labeling ► IGF-1 loaded porous chitosan found to be very effective for bone defect healing.

  8. Dietary glycemic load, glycemic index, and associated factors in a multiethnic cohort of midlife women.

    Science.gov (United States)

    Hu, Youqing; Block, Gladys; Sternfeld, Barbara; Sowers, MaryFran

    2009-12-01

    Dietary glycemic load (GL) and glycemic index (GI), indicators of the postprandial glucose and insulin response to carbohydrate composition of diet, have been suggested as independent risk factors for cardiovascular disease and diabetes. However, current knowledge about the distribution, correlates, and major contributors of these measures in human populations is limited. To describe the intakes and correlates of GL and GI in African American, Caucasian, Chinese, and Japanese women in the Study of Women's Health Across the Nation (SWAN). Data are from 2025 women participating in SWAN, a multi-ethnic, community-based cohort study of women transitioning into menopause. GL and GI were estimated from dietary information obtained in the fifth year of the study using a modified Block food frequency questionnaire. The relationship of GL and GI to dietary factors and selected demographic measures, including race/ethnicity and lifestyle factors, was examined using bivariate and multivariate analyses. GI and GL were consistently lower in Caucasian women than in African American, Japanese, or Chinese women. Education was inversely associated with GL and alcohol consumption was inversely associated with GI among all ethnic groups. The association between family income and glycemic measures varied across ethnic groups. GI was positively associated with consumption of grains and potatoes and inversely associated with consumption of fruits, juices, dairy foods, protein sources, and sweets among all ethnic groups. It is important for researchers to consider factors such as ethnicity, family income, and alcohol intake as potential confounders when investigating the associations of GL and GI with disease.

  9. Factors affecting the duration of nestling period and fledging order in Tengmalm's owl (Aegolius funereus: effect of wing length and hatching sequence.

    Directory of Open Access Journals (Sweden)

    Marek Kouba

    Full Text Available In altricial birds, the nestling period is an important part of the breeding phase because the juveniles may spend quite a long time in the nest, with associated high energy costs for the parents. The length of the nestling period can be variable and its duration may be influenced by both biotic and abiotic factors; however, studies of this have mostly been undertaken on passerine birds. We studied individual duration of nestling period of 98 Tengmalm's owl chicks (Aegolius funereus at 27 nests during five breeding seasons using a camera and chip system and radio-telemetry. We found the nestlings stayed in the nest box for 27 - 38 days from hatching (mean ± SD, 32.4 ± 2.2 days. The individual duration of nestling period was negatively related to wing length, but no formally significant effect was found for body weight, sex, prey availability and/or weather conditions. The fledging sequence of individual nestlings was primarily related to hatching order; no relationship with wing length and/or other factors was found in this case. We suggest the length of wing is the most important measure of body condition and individual quality in Tengmalm's owl young determining the duration of the nestling period. Other differences from passerines (e.g., the lack of effect of weather or prey availability on nestling period are considered likely to be due to different life-history traits, in particular different food habits and nesting sites and greater risk of nest predation among passerines.

  10. Conservative flight with a varying load factor and closed form solutions to the aircraft motion – A technical note

    Indian Academy of Sciences (India)

    S N Maitra

    2010-12-01

    Conservative flight performance of an aircraft with constant load factor was analysed by Miele. In this paper, conservative flight with a varying load factor is considered. The load factor being a control parameter is varied in such a way that it gives rise to closed-form solutions to aircraft motion. With this typical load factor function the geometry of the trajectory has been found to be a loop as is with Miele’s analysis. Finally, the range and endurance have been determined for two different constant parameters associated with the load factor function.

  11. Quantification of finger joint loadings using musculoskeletal modelling clarifies mechanical risk factors of hand osteoarthritis.

    Science.gov (United States)

    Goislard de Monsabert, Benjamin; Vigouroux, Laurent; Bendahan, David; Berton, Eric

    2014-02-01

    Owing to limited quantitative data related to the loadings (forces and pressures) acting upon finger joints, several clinical observations regarding mechanical risk factors of hand osteoarthritis remain misunderstood. To improve the knowledge of this pathology, the present study used musculoskeletal modelling to quantify the forces and pressures acting upon hand joints during two grasping tasks. Kinematic and grip force data were recorded during both a pinch and a power grip tasks. Three-dimensional magnetic resonance imaging measurements were conducted to quantify joint contact areas. Using these datasets as input, a musculoskeletal model of the hand and wrist, including twenty-three degrees of freedom and forty-two muscles, has been developed to estimate joint forces and joint pressures. When compared with the power grip task, the pinch grip task resulted in two to eight times higher joint loadings whereas the grip forces exerted on each finger were twice lower. For both tasks, joint forces and pressures increased along a disto-proximal direction for each finger. The quantitative dataset provided by the present hand model clarified two clinical observations about osteoarthritis development which were not fully understood, i.e., the strong risk associated to pinch grip tasks and the high frequency of thumb-base osteoarthritis.

  12. Assessment of Various Risk Factors for Success of Delayed and Immediate Loaded Dental Implants: A Retrospective Analysis.

    Science.gov (United States)

    Prasant, M C; Thukral, Rishi; Kumar, Sachin; Sadrani, Sannishth M; Baxi, Harsh; Shah, Aditi

    2016-10-01

    Ever since its introduction in 1977, a minimum of few months of period is required for osseointegration to take place after dental implant surgery. With the passage of time and advancements in the fields of dental implant, this healing period is getting smaller and smaller. Immediate loading of dental implants is becoming a very popular procedure in the recent time. Hence, we retrospectively analyzed the various risk factors for the failure of delayed and immediate loaded dental implants. In the present study, retrospective analysis of all the patients was done who underwent dental implant surgeries either by immediate loading procedure or by delayed loading procedures. All the patients were divided broadly into two groups with one group containing patients in which delayed loaded dental implants were placed while other consisted of patients in whom immediate loaded dental implants were placed. All the patients in whom follow-up records were missing and who had past medical history of any systemic diseases were excluded from the present study. Evaluation of associated possible risk factors was done by classifying the predictable factors as primary and secondary factors. All the results were analyzed by Statistical Package for the Social Sciences (SPSS) software. Kaplan-Meier survival analyses and chi-square test were used for assessment of level of significance. In delayed and immediate group of dental implants, mean age of the patients was 54.2 and 54.8 years respectively. Statistically significant results were obtained while comparing the clinical parameters of the dental implants in both the groups while demographic parameters showed nonsignificant correlation. Significant higher risk of dental implant failure is associated with immediate loaded dental implants. Tobacco smoking, shorter implant size, and other risk factors play a significant role in predicting the success and failure of dental implants. Delayed loaded dental implant placement should be preferred

  13. Stress intensity factors of eccentric cracks in bi-materials plate under mode I loading

    Energy Technology Data Exchange (ETDEWEB)

    Ismail, A. E. [Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, 86400 Batu Pahat, Johor (Malaysia)

    2015-05-15

    Bi-material plates were generally used to joint electronic devices or mechanical components requiring dissimilar materials to be attached. During services, mechanical failure can be occurred due to the formation of cracks at the interfacial joint or away from the centre. Generally, linear elastic fracture mechanics approach is used to characterize these cracks based on stress intensity factors (SIF). Based on the literature survey, the SIFs for the central cracks were easily available. However, the SIFs for eccentric cracks were difficult to obtain. Therefore, this paper presented the SIFs for eccentric cracks subjected to mode I tension loading. Three important parameters were used such as relative crack depth, a/L, relative offset distance, b/L and elastic mismatch, E{sub 1}/E{sub 2} or α. It was found that such parameters significantly affected the characteristic of SIFs and it was depend on the location of cracks.

  14. Renyi Criterion Modification in Testing the Hypotheses About Acceleration Factor Meaning at Variable-Load Tests

    Directory of Open Access Journals (Sweden)

    N. D. Tiannikova

    2014-01-01

    Full Text Available This paper concerns the acceleration factor estimation at strenuous tests of products in case of unstable production process (different batches of the same products may be with different index of reliability.Kartashov has developed techniques for determining the invariant functional from batch to batch, which convert accelerated test results to the normal mode. Its highlight is to conduct socalled preliminary tests of one sample of products, including pre-tests in the variable mode. The standard procedure for the preliminary tests (examination is as follows: testing the n groups of products, with m elements in each group, begins in the normal mode. As soon as one of the products in the group fails, tests of remaining products start in the accelerated mode. In addition to tests in the variable mode, there are also tests conducted in the constantly normal mode. As a result of such tests of products from one batch, an acceleration factor of strenuous tests is determined for this type of products for any batch.The described procedure has the following shortcomings:• tests duration in the normal mode is long and, as a result, is very much time-consuming and cost-demandable;• tests conducted in the variable mode to the failure of all the products have the same drawback.This paper proposes a method for conducting the preliminary studies. It does not require testing in the constant mode and, additionally, allows tests duration in the variable mode to be restricted by the moment of the first failure in the r group. To analyze the results of such tests the Renyi type criterion of homogeneity of two samples is suggested. A method for calculating the distribution of its statistics for the finite sample sizes is developed and implemented in the software complex. The asymptotic distribution of the statistics is given. The estimate of the acceleration factor is provided by its minimization. It is shown that for real sample sizes of products only exact

  15. Dietary glycemic index, glycemic load, and cardiovascular disease risk factors: Tehran Lipid and Glucose Study.

    Science.gov (United States)

    Hosseinpour-Niazi, Somayeh; Sohrab, Golbon; Asghari, Golaleh; Mirmiran, Parvin; Moslehi, Nazanin; Azizi, Fereidoun

    2013-07-01

    Data available on the effect of quality (glycemic index [GI]) and quantity (glycemic load [GL]) of carbohydrates on the risk factors of cardiovascular disease (CVD) are inconsistent. The objective of this study was to examine the association between dietary GI, GL, and CVD risk factors among Tehranian adults, the participants of the Tehran Lipid and Glucose Study. This population- based cross-sectional study was conducted on 2457 subjects (46% men and 54% women), aged 19 to 84 years. Dietary GI and GL were measured using a validated 168- item semiquantitative food frequency questionnaire. Anthropometrics, blood pressure, fasting blood glucose, and lipid profiles were measured. The mean intakes of GI and GL were 68.3 and 244.8, respectively. Rice (26.6%) and bread (19.0%) were the major contributors to dietary GI and GL, respectively. Higher dietary GI and GL were associated with high intakes of carbohydrate, fiber, refined grain, fruits, simple sugar, snack, and desserts. After adjustment for lifestyle and dietary variables, a higher dietary GI was positively associated with triglycerides and high-density lipoprotein (HDL) cholesterol concentrations among obese subjects. Dietary GL was positively associated with fasting and 2-h blood glucose among nonobese subjects, after adjustment for confounders.   Dietary GI and GL were associated with a few CVD risk factors, and body mass index levels may modulate these associations.

  16. Determination of the ISO face load factor in spur gear drives by the finite element modeling of gears and shafts

    OpenAIRE

    2013-01-01

    The face load factor is a common coefficient used in gear design standards that takes into account the uneven distribution of load across the face width of the gears caused by the mesh misalignment. In this paper, a finite element model that includes the gears and the corresponding shafts is proposed. The results obtained from the application of finite element analysis to this model are compared with those obtained from application of the ISO Standard 6336 coefficient-based method (Method C)....

  17. Investigating the Effects of Loading Factors on the In Vitro Pharmaceutical Performance of Mesoporous Materials as Drug Carriers for Ibuprofen

    Directory of Open Access Journals (Sweden)

    Junmin Lai

    2017-02-01

    Full Text Available The aim of the study was to investigate the effects of the loading factors, i.e., the initial drug loading concentration and the ratio of the drug to carriers, on the in vitro pharmaceutical performance of drug-loaded mesoporous systems. Ibuprofen (IBU was used as a model drug, and two non-ordered mesoporous materials of commercial silica Syloid® 244FP (S244FP and Neusilin® US2 (NS2 were selected in the study. The IBU-loaded mesoporous samples were prepared by a solvent immersion method with a rotary evaporation drying technique and characterized by polarized light microscopy (PLM, Fourier transform infrared (FTIR spectroscopy, X-ray powder diffraction (XRPD and differential scanning calorimetry (DSC. Dissolution experiments were performed in simulated gastric media at 37 °C under non-sink conditions. The concentration of IBU in solution was determined by HPLC. The study showed that the dissolution rate of IBU can be improved significantly using the mesoporous S224FP carriers due to the conversion of crystalline IBU into the amorphous form. Both of the loading factors affected the IBU dissolution kinetics. Due to the molecular interaction between the IBU and NS2 carriers, the loading factors had little effects on the drug release kinetics with incomplete drug desorption recovery and insignificant dissolution enhancement. Care and extensive evaluation must therefore be taken when mesoporous materials are chosen as carrier delivery systems.

  18. 大学生考期应激的特征及原因分析%CHARACTERISTICS AND FACTOR ANALYSIS OF TEST-DURATION STRESS FOR COLLEGE STUDENTS

    Institute of Scientific and Technical Information of China (English)

    张智君; 霍燕

    2001-01-01

    旨在研究考期应激的表现特征,并探讨其产生的原因和影响因素。以问卷方法测量了261名在校大学生。结果发现47.89%的被试有不同程度的考期应激症状,其中以睡眠症状为最典型的特征。考期应激症状很少受性别、专业、年级、是否担任班干部和个性倾向等因素的影响,且具有较明显的时间特征。诱发考期应激的主要因素有:考生"对考试目的的认知"、"对考试内容的认知"及"生活和学习环境"等。结论为,考期应激是一种大学生中较普遍且具有多重原因的应激现象。%Test-Duration Stress (TDS) is a popular phenomenon for college students during term exams and often make some detrimental impacts on performances and health of college students. Therefore, it is very important to examine the characteristics of Test-Duration Stress and explore the possible factors it resulted from. Two questionnaires, the Scale for Characteristics of Test-Duration Stress (SCTDS) and Scale for Factors of Test-Duration Stress (SFTDS), were specially designed and employed in the present study. Two hundred and sixty-one college students, 152 males and 109 females, were selected as subjects, who were 18 to 26 years of age including all four grade students. From the results of SCTDS evaluation, it was surprisedly found that totally one hundred and twenty-five subjects (high as 47.89percent) showed some significant symptoms of Test-Duration Stress. The sleeping symptom was especially seen among them, and there were very significant differences in sleepless scores between the TDS group (4.932±+ 2.374) and the normal group (3.563±+ 2.431). There were also some great differences in other symptoms such as digestion, cognitive capacity, headache and immunity, which were all significant statistically. But all the symptoms were rarely affected by such variables as sex, specialty,grade, roles and personality except sex difference in headache symptom

  19. Effects of nerve growth factor on the action potential duration and repolarizing currents in a rabbit model of myocardial infarction

    OpenAIRE

    Lan, Yun-Feng; Zhang, Jian-Cheng; Gao, Jin-Lao; Wang, Xue-Ping; Fang, Zhou; Fu, Yi-Cheng; Chen, Mei-Yan; Lin, Min; Xue, Qiao; Li, Yang

    2013-01-01

    Objectives To investigate the effect of nerve growth factor (NGF) on the action potential and potassium currents of non-infarcted myocardium in the myocardial infarcted rabbit model. Methods Rabbits with occlusion of the left anterior descending coronary artery were prepared and allowed to recover for eight weeks (healed myocardial infarction, HMI). During ligation surgery of the left coronary artery, a polyethylene tube was placed near the left stellate ganglion in the subcutis of the neck f...

  20. Anal human papillomavirus in HIV-uninfected men who have sex with men: incidence and clearance rates, duration of infection, and risk factors.

    Science.gov (United States)

    Donà, M G; Vescio, M F; Latini, A; Giglio, A; Moretto, D; Frasca, M; Benevolo, M; Rollo, F; Colafigli, M; Cristaudo, A; Giuliani, M

    2016-12-01

    Little is known regarding the natural history of anal human papillomavirus (HPV) infection. We aimed to evaluate incidence and clearance rates, their risk factors, and duration of anal HPV infection in HIV-uninfected men who have sex with men (MSM). A longitudinal study was conducted. Anal samples were analysed using the Linear Array HPV Genotyping test. Incidence and clearance rates, and corresponding risk factors, were estimated using a two-state Markov model. Overall, 155 MSM (median age 33.4 years) attending the largest sexually transmitted infection (STI) centre in Rome, Italy, were followed for a median of 12.2 months (Q1-Q3: 7.0-18.1). Incidence and clearance rates for any HPV were 85.6 (95% CI: 58.4-125.4) and 35.6 (95% CI: 24.7-51.5) × 1000 person-months, respectively; the median duration of infection was 9.4 months (Q1-Q3: 7.5-12.1). Receptive anal sex emerged as the only risk factor for the acquisition of any HPV (Hazard Ratio, HR = 2.65, 95% CI: 1.16-6.06). The incidence rates for carcinogenic and non-carcinogenic types were 42.3 (95% CI: 29.2-61.4) and 29.2 (95% CI: 19.5-43.7) × 1000 person-months, respectively (p = 0.13); their clearance rates were 62.9 (95% CI: 45.1-87.7) and 65.7 (95% CI: 47.4-91.0) × 1000 person-months, respectively (p = 0.83). HPV16 showed the lowest clearance rate among carcinogenic types (59.7 × 1000 person-months), and a duration of infection of 16.8 months. In conclusion, a higher incidence rate was observed for carcinogenic compared to non-carcinogenic HPV types, although the difference was not significant. HPV16 emerged as the type with the longest duration of infection and the lowest clearance rate among carcinogenic types.

  1. Relation of Adiponectin to Glucose Tolerance Status, Adiposity, and Cardiovascular Risk Factor Load

    Directory of Open Access Journals (Sweden)

    N. Wolfson

    2012-01-01

    Full Text Available Objective. Adiponectin has anti-atherogenic and anti-inflammatory properties. We investigated the influence of adiponectin on glucose tolerance status, adiposity and cardiovascular risk factors (CVRFs. Design and Patients. Study consisted of 107 subjects: 55 with normal glucose tolerance (NGT and 52 with impaired glucose regulation (IGR who were divided into two groups: 24 subjects with impaired fasting glucose (IFG Group and 28 patients with type 2 diabetes mellitus (DM Group. In additional analysis, study participants were divided into two groups, according to CVRFs: low and high risk. Measurements: Patients were evaluated for glucose, HbA1C, insulin, lipids, CRP, HOMA-IR and adiponectin. Measurements. Patients were evaluated for glucose, HbA1C, insulin, lipids, CRP, HOMA-IR and adiponectin. Results. Adiponectin was significantly higher in NGT group than in IFG (=0.003 and DM (=0.01 groups. Adiponectin was significantly, positively associated with HDL and inversely associated with glucose, HbA1c, ALT, AST, TG, HOMA-IR. Patients with higher CVRFs load have lesser adiponectin compared to patients with low cardiovascular risk <0.0001. Adiponectin was inversely associated with the number of risk factors (=−0.430, =0.0001. Conclusions. Circulating adiponectin was significantly lower in subjects with different degree of IGR compared to subjects with normal glucose homeostasis. Adiponectin was significantly lower in high risk group than low risk group and decreased concurrently with increased number of CVRFs.

  2. Dietary glycemic index and glycemic load and their relationship to cardiovascular risk factors in Chinese children.

    Science.gov (United States)

    Zhang, Xinyu; Zhu, Yanna; Cai, Li; Ma, Lu; Jing, Jin; Guo, Li; Jin, Yu; Ma, Yinghua; Chen, Yajun

    2016-04-01

    The purpose of this study was to examine the cross-sectional associations between dietary glycemic index (GI) and glycemic load (GL) and cardiovascular disease (CVD) risk factors in Chinese children. A total of 234 Chinese schoolchildren aged 8-11 years in Guangdong participated in the study. Dietary intake was assessed via a 3-day dietary record. Seven established cardiovascular indicators were analyzed in this study: fasting plasma glucose (FPG), fasting triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), systolic blood pressure, and diastolic blood pressure. Higher dietary GI was significantly associated with higher TG levels (P = 0.037) and lower HDL-C levels (P = 0.005) after adjusting for age, sex, nutritional intake, physical activity, and body mass index z score. LDL-C was found to differ across tertiles of dietary GL. The middle tertile tended to show the highest level of LDL-C. TC, FPG, and blood pressure were independent of both dietary GI and GL. Our findings suggest that higher dietary GI is differentially associated with some CVD risk factors, including lower HDL-C and higher TG, in school-aged children from south China.

  3. A waste load allocation method based on unfairness factors and its application in the Zhangweinan Watershed, northern China.

    Science.gov (United States)

    Qiu, Ruzhi; Li, Yingxia; Yang, Zhifeng; Li, Chunhui; Yu, Jingshan; Shi, Jianghong

    2010-01-01

    A waste load allocation method was developed for industrial wastewater management based on unfairness factors, an industrial allocation factor and pollution reduction discounts. Three unfairness factors were defined to assess the relative efficiencies of energy consumption, pollution discharge and waste treatment costs for different industries. The overall effect of these factors was described by an industrial allocation factor. Based on the values of these factors, industries were classified into three types, after which waste load allocation proportions among different industries were determined using different pollution reduction discounts. This waste load allocation method was then applied in the Zhangweinan Watershed, which is one of the most seriously polluted watersheds in northern China. The results revealed that extractive, mechanical and food industries comprise the type I industries, which had the lowest pollution reduction discounts of 0, 0.25 and 0.5, respectively. The metallurgical industry and other industries were characterized as type II and discounts of 0.5 and 0.6 were given to their primary reductions. Textile, pharmaceutical, oil and pyrogenic, chemical and paper industries were classified as type III industries and had a waste load reduction of more than 80% of the pollution discharge in 2004.

  4. (*) Central Growth Factor Loaded Depots in Bone Tissue Engineering Scaffolds for Enhanced Cell Attraction.

    Science.gov (United States)

    Quade, Mandy; Knaack, Sven; Akkineni, Ashwini Rahul; Gabrielyan, Anastasia; Lode, Anja; Rösen-Wolff, Angela; Gelinsky, Michael

    2017-08-01

    Tissue engineering, the application of stem and progenitor cells in combination with an engineered extracellular matrix, is a promising strategy for bone regeneration. However, its success is limited by the lack of vascularization after implantation. The concept of in situ tissue engineering envisages the recruitment of cells necessary for tissue regeneration from the host environment foregoing ex vivo cell seeding of the scaffold. In this study, we developed a novel scaffold system for enhanced cell attraction, which is based on biomimetic mineralized collagen scaffolds equipped with a central biopolymer depot loaded with chemotactic agents. In humid milieu, as after implantation, the signaling factors are expected to slowly diffuse out of the central depot forming a gradient that stimulates directed cell migration toward the scaffold center. Heparin, hyaluronic acid, and alginate have been shown to be capable of depot formation. By using vascular endothelial growth factor (VEGF) as model factor, it was demonstrated that the release kinetics can be adjusted by varying the depot composition. While alginate and hyaluronic acid are able to reduce the initial burst and prolong the release of VEGF, the addition of heparin led to a much stronger retention that resulted in an almost linear release over 28 days. The biological activity of released VEGF was proven for all variants using an endothelial cell proliferation assay. Furthermore, migration experiments with endothelial cells revealed a relationship between the degree of VEGF retention and migration distance: cells invaded deepest in scaffolds containing a heparin-based depot indicating that the formation of a steep gradient is crucial for cell attraction. In conclusion, this novel in situ tissue engineering approach, specifically designed to recruit and accommodate endogenous cells upon implantation, appeared highly promising to stimulate cell invasion, which in turn would promote vascularization and finally new

  5. Duration of cognitive dysfunction after concussion, and cognitive dysfunction as a risk factor: a population study of young men

    DEFF Research Database (Denmark)

    Teasdale, T W; Engberg, A

    1997-01-01

    OBJECTIVES: To establish how long cognitive dysfunction lasts after concussion, and the extent to which it may be a predisposing risk factor for concussion, by examining the prevalence of cognitive dysfunction among young men who have sustained concussion. DESIGN: Observational study. SETTING......: Denmark. SUBJECTS: 1220 young men who had been admitted to hospital for concussion between the ages of 16 and 24 (identified in a national register of admissions) and who had also been cognitively tested by the Danish conscription draft board. MAIN OUTCOME MEASURE: Score on the draft board's cognitive...... screening test, dichotomised as dysfunctional or non-dysfunctional (20.4% of the general population of Danish men appearing before the draft board had a dysfunctional score). RESULTS: 700 of the 1220 men had been tested after sustaining concussion; 520 had been tested before concussion. Four (50...

  6. Risk factors associated with increased bovine leukemia virus proviral load in infected cattle in Japan from 2012 to 2014.

    Science.gov (United States)

    Ohno, Ayumu; Takeshima, Shin-nosuke; Matsumoto, Yuki; Aida, Yoko

    2015-12-02

    Bovine leukemia virus (BLV) is the causative agent of enzootic bovine leukosis, a malignant B cell lymphoma. BLV has spread worldwide and causes serious problems. After infection, the BLV genome is integrated into the host DNA and can be amplified during periods of latency. We previously designed degenerate primers using the Coordination of Common Motifs (CoCoMo) algorithm to establish a new quantitative real-time PCR method (BLV-CoCoMo-qPCR-2) of measuring the proviral load of both known and novel BLV variants. Here, we aimed to examine the correlation between proviral load and risk factors for BLV infection, such as breeding systems, parousity, and colostrum feeding. Blood and serum samples were collected from 83 BLV-positive farms in 22 prefectures of Japan, and the BLV proviral load and anti-BLV antibody levels were measured. BLV was detected in 73.3% (1039/1,417) of cattle by BLV-CoCoMo-qPCR-2 and the provirus was detected in 93 of 1039 antibody-negative samples. The results showed that the proviral load increased with progression of lymphocytosis. Next, the risk factors associated with increasing BLV infection rate were examined along with any association with proviral load. The proviral load was higher in cattle with lymphocytosis than in healthy cattle, and higher in multiparous cows than in nulliparous cows. Finally, proviral loads were higher in contact breeding systems than in non-contact breeding systems. Taken together, these findings may help to formulate a plan for eliminating BLV from contaminated farms. This is the first nationwide study to estimate BLV proviral load in Japanese cattle.

  7. Nearshore hydrodynamics as loading and forcing factors for Escherichia coli contamination at an embayed beach

    Science.gov (United States)

    Ge, Zhongfu; Whitman, Richard L.; Nevers, Meredith B.; Phanikumar, Mantha S.; Byappanahalli, Muruleedhara N.

    2012-01-01

    Numerical simulations of the transport and fate of Escherichia coli were conducted at Chicago's 63rd Street Beach, an embayed beach that had the highest mean E. coli concentration among 23 similar Lake Michigan beaches during summer months of 2000-2005, in order to find the cause for the high bacterial contamination. The numerical model was based on the transport of E. coli by current circulation patterns in the embayment driven by longshore main currents and the loss of E. coli in the water column, taking settling as well as bacterial dark- and solar-related decay into account. Two E. coli loading scenarios were considered: one from the open boundary north of the embayment and the other from the shallow water near the beachfront. Simulations showed that the embayed beach behaves as a sink for E. coli in that it generally receives E. coli more efficiently than it releases them. This is a result of the significantly different hydrodynamic forcing factors between the inside of the embayment and the main coastal flow outside. The settled E. coli inside the embayment can be a potential source of contamination during subsequent sediment resuspension events, suggesting that deposition-resuspension cycles of E. coli have resulted in excessive bacterial contamination of beach water. A further hypothetical case with a breakwater shortened to half its original length, which was anticipated to enhance the current circulation in the embayment, showed a reduction in E. coli concentrations of nearly 20%.

  8. Clinical Factors and Viral Load Influencing Severity of Acute Hepatitis A.

    Science.gov (United States)

    Lee, Hyun Woong; Chang, Dong-Yeop; Moon, Hong Ju; Chang, Hye Young; Shin, Eui-Cheol; Lee, June Sung; Kim, Kyung-Ah; Kim, Hyung Joon

    2015-01-01

    Clinical manifestations of hepatitis A virus (HAV) infection vary from mild to fulminant hepatic failure (FHF) in adults. We investigated the relationship between laboratory findings, including viral load, and clinical outcomes in patients with acute hepatitis A (AHA) and evaluated predictive factors for severe acute hepatitis (s-AH). We analyzed the clinical manifestations of AHA in 770 patients. Patients with a prothrombin time (PT) of less than 40% of normal were classified as s-AH and included 4 patients with FHF, 11 patients with acute renal failure, and 3 patients with prolonged jaundice (n = 128). Other patients were defined as mild acute hepatitis (m-AH) (n = 642). Serum samples were obtained from 48 patients with acute hepatitis A. Among them, 20 with s-AH, and 28 with m-AH, were tested for HAV RNA titer. In a multivariate analysis, age (HR = 1.042, P = 0.041), peak creatinine (HR = 4.014, P = 0.001), bilirubin (HR = 1.153, P = 0.003), alanine aminotransferase (ALT) (HR = 1.001, P hepatitis A.

  9. Evaluation of Dynamic Load Factors for a High-Speed Railway Truss Arch Bridge

    Directory of Open Access Journals (Sweden)

    Ding Youliang

    2016-01-01

    Full Text Available Studies on dynamic impact of high-speed trains on long-span bridges are important for the design and evaluation of high-speed railway bridges. The use of the dynamic load factor (DLF to account for the impact effect has been widely accepted in bridge engineering. Although the field monitoring studies are the most dependable way to study the actual DLF of the bridge, according to previous studies there are few field monitoring data on high-speed railway truss arch bridges. This paper presents an evaluation of DLF based on field monitoring and finite element simulation of Nanjing DaShengGuan Bridge, which is a high-speed railway truss arch bridge with the longest span throughout the world. The DLFs in different members of steel truss arch are measured using monitoring data and simulated using finite element model, respectively. The effects of lane position, number of train carriages, and speed of trains on DLF are further investigated. By using the accumulative probability function of the Generalized Extreme Value Distribution, the probability distribution model of DLF is proposed, based on which the standard value of DLF within 50-year return period is evaluated and compared with different bridge design codes.

  10. Clinical Factors and Viral Load Influencing Severity of Acute Hepatitis A

    Science.gov (United States)

    Lee, Hyun Woong; Chang, Dong-Yeop; Moon, Hong Ju; Chang, Hye Young; Shin, Eui-Cheol; Lee, June Sung; Kim, Kyung-Ah; Kim, Hyung Joon

    2015-01-01

    Background and Aims Clinical manifestations of hepatitis A virus (HAV) infection vary from mild to fulminant hepatic failure (FHF) in adults. We investigated the relationship between laboratory findings, including viral load, and clinical outcomes in patients with acute hepatitis A (AHA) and evaluated predictive factors for severe acute hepatitis (s-AH). Methods We analyzed the clinical manifestations of AHA in 770 patients. Patients with a prothrombin time (PT) of less than 40% of normal were classified as s-AH and included 4 patients with FHF, 11 patients with acute renal failure, and 3 patients with prolonged jaundice (n = 128). Other patients were defined as mild acute hepatitis (m-AH) (n = 642). Serum samples were obtained from 48 patients with acute hepatitis A. Among them, 20 with s-AH, and 28 with m-AH, were tested for HAV RNA titer. Results In a multivariate analysis, age (HR = 1.042, P = 0.041), peak creatinine (HR = 4.014, P = 0.001), bilirubin (HR = 1.153, P = 0.003), alanine aminotransferase (ALT) (HR = 1.001, Phepatitis A. PMID:26090677

  11. Long-duration effect of multi-factor stresses on the cellular biochemistry, oil-yielding performance and morphology of Nannochloropsis oculata.

    Science.gov (United States)

    Wei, Likun; Huang, Xuxiong

    2017-01-01

    Microalga Nannochloropsis oculata is a promising alternative feedstock for biodiesel. Elevating its oil-yielding capacity is conducive to cost-saving biodiesel production. However, the regulatory processes of multi-factor collaborative stresses (MFCS) on the oil-yielding performance of N. oculata are unclear. The duration effects of MFCS (high irradiation, nitrogen deficiency and elevated iron supplementation) on N. oculata were investigated in an 18-d batch culture. Despite the reduction in cell division, the biomass concentration increased, resulting from the large accumulation of the carbon/energy-reservoir. However, different storage forms were found in different cellular storage compounds, and both the protein content and pigment composition swiftly and drastically changed. The analysis of four biodiesel properties using pertinent empirical equations indicated their progressive effective improvement in lipid classes and fatty acid composition. The variation curve of neutral lipid productivity was monitored with fluorescent Nile red and was closely correlated to the results from conventional methods. In addition, a series of changes in the organelles (e.g., chloroplast, lipid body and vacuole) and cell shape, dependent on the stress duration, were observed by TEM and LSCM. These changes presumably played an important role in the acclimation of N. oculata to MFCS and accordingly improved its oil-yielding performance.

  12. Passive Repetitive Stretching for a Short Duration within a Week Increases Myogenic Regulatory Factors and Myosin Heavy Chain mRNA in Rats' Skeletal Muscles

    Directory of Open Access Journals (Sweden)

    Yurie Kamikawa

    2013-01-01

    Full Text Available Stretching is a stimulation of muscle growth. Stretching for hours or days has an effect on muscle hypertrophy. However, differences of continuous stretching and repetitive stretching to affect muscle growth are not well known. To clarify the difference of continuous and repetitive stretching within a short duration, we investigated the gene expression of muscle-related genes on stretched skeletal muscles. We used 8-week-old male Wistar rats ( for this study. Animals medial gastrocnemius muscle was stretched continuously or repetitively for 15 min daily and 4 times/week under anesthesia. After stretching, muscles were removed and total RNA was extracted. Then, reverse transcriptional quantitative real-time PCR was done to evaluate the mRNA expression of MyoD, myogenin, and embryonic myosin heavy chain (MyHC. Muscles, either stretched continuously or repetitively, increased mRNA expression of MyoD, myogenin, and embryonic MyHC more than unstretched muscles. Notably, repetitive stretching resulted in more substantial effects on embryonic MyHC gene expression than continuous stretching. In conclusion, passive stretching for a short duration within a week is effective in increasing myogenic factor expression, and repetitive stretching had more effects than continuous stretching for skeletal muscle on muscle growth. These findings are applicable in clinical muscle-strengthening therapy.

  13. Monitoring organic loading to swimming pools by fluorescence excitation–emission matrix with parallel factor analysis (PARAFAC)

    DEFF Research Database (Denmark)

    Seredynska-Sobecka, Bozena; Stedmon, Colin; Boe-Hansen, Rasmus

    2011-01-01

    Fluorescence Excitation–Emission Matrix spectroscopy combined with parallel factor analysis was employed to monitor water quality and organic contamination in swimming pools. The fluorescence signal of the swimming pool organic matter was low but increased slightly through the day. The analysis...... loading in swimming pool water. The fluorescence at 420nm gradually increased during opening hours and represented material accumulating through the day....

  14. Spinal mechanical load as a risk factor for low back pain: A systematic review of prospective cohort studies

    NARCIS (Netherlands)

    E.W.P. Bakker; A.P. Verhagen; E. van Trijffel; C. Lucas; B.W. Koes

    2009-01-01

    Study Design. Systematic review. Objective. To review and critically evaluate the past literature for spinal mechanical load as risk factor for low back pain (LBP). Summary of Background Data. LBP is a costly health problem worldwide, and treatments are often unsuccessful. Therefore, prevention migh

  15. Comprehensive analysis of the factors affecting the duration of the existence of subcutaneous seroma after surgical treatment of breast cancer patients

    Directory of Open Access Journals (Sweden)

    I. B. Schepotin

    2014-01-01

    Full Text Available Subcutaneous seroma formation is the most common complication of surgical treatment for breast cancer and occurs in 15–85 % of patients. Seroma can cause infection and/or long-term postoperative wound healing, increase the length of stay of patients in the surgical hospital, delaying the start of rehabilitation and adjuvant therapy, increase the cost of treatment, which significantly affects the quality of life of patients and reduces the cost-effectiveness of treatment. In this prospective study examined the factors that affect the duration of seroma in patients after surgical treatment of patients with breast cancer as the first stage in the development and implementation of prevention and treatment protocols subcutaneous seroma.

  16. Transcription factor assisted loading and enhancer dynamics dictate the hepatic fasting response

    Science.gov (United States)

    Goldstein, Ido; Baek, Songjoon; Presman, Diego M.; Paakinaho, Ville; Swinstead, Erin E.; Hager, Gordon L.

    2017-01-01

    Fasting elicits transcriptional programs in hepatocytes leading to glucose and ketone production. This transcriptional program is regulated by many transcription factors (TFs). To understand how this complex network regulates the metabolic response to fasting, we aimed at isolating the enhancers and TFs dictating it. Measuring chromatin accessibility revealed that fasting massively reorganizes liver chromatin, exposing numerous fasting-induced enhancers. By utilizing computational methods in combination with dissecting enhancer features and TF cistromes, we implicated four key TFs regulating the fasting response: glucocorticoid receptor (GR), cAMP responsive element binding protein 1 (CREB1), peroxisome proliferator activated receptor alpha (PPARA), and CCAAT/enhancer binding protein beta (CEBPB). These TFs regulate fuel production by two distinctly operating modules, each controlling a separate metabolic pathway. The gluconeogenic module operates through assisted loading, whereby GR doubles the number of sites occupied by CREB1 as well as enhances CREB1 binding intensity and increases accessibility of CREB1 binding sites. Importantly, this GR-assisted CREB1 binding was enhancer-selective and did not affect all CREB1-bound enhancers. Single-molecule tracking revealed that GR increases the number and DNA residence time of a portion of chromatin-bound CREB1 molecules. These events collectively result in rapid synergistic gene expression and higher hepatic glucose production. Conversely, the ketogenic module operates via a GR-induced TF cascade, whereby PPARA levels are increased following GR activation, facilitating gradual enhancer maturation next to PPARA target genes and delayed ketogenic gene expression. Our findings reveal a complex network of enhancers and TFs that dynamically cooperate to restore homeostasis upon fasting. PMID:28031249

  17. Duration of symptoms

    DEFF Research Database (Denmark)

    Hansen, Olfred; Larsen, Susanne; Bastholt, Lars

    2005-01-01

    PURPOSE: To study the relationship between the durations of symptoms before the start of radiotherapy and treatment outcome in Stage I-III glottic cancer. METHODS AND MATERIALS: From 1965 to 1997, 611 glottic cancer patients from the Southern Region of Denmark were treated with primary radiotherapy....... A total of 544 patients fulfilled the criteria for inclusion to the study (Stage I-III glottic cancer, a duration of symptoms less than or equal to 36 months, primary radiotherapy with at least 50 Gy and sufficient data for analysis). The total radiation dose ranged from 50.0 to 71.6 Gy in 22 to 42...... of symptoms was a significant factor (p symptoms was statistically...

  18. Relationships of sleep duration with sociodemographic and health-related factors, psychiatric disorders and sleep disturbances in a community sample of Korean adults.

    Science.gov (United States)

    Park, Subin; Cho, Maeng Je; Chang, Sung Man; Bae, Jae Nam; Jeon, Hong Jin; Cho, Seong-Jin; Kim, Byung-Soo; Chung, In-Won; Ahn, Joon Ho; Lee, Hae Woo; Hong, Jin Pyo

    2010-12-01

    The aim of this study is to examine relationships of sleep duration with sociodemographic and health-related factors, psychiatric disorders and sleep disturbances in a nationwide sample in Korea. A total of 6510 subjects aged 18-64 years participated in this study. Logistic regression was used to calculate the odd ratios and 95% confidence intervals of the covariates, psychiatric disorders and sleep disturbances across the following sleep duration categories: 5 h or less, 6, 7, 8 and 9 h or more per day. Low levels of education, unemployment and physical illness were associated with sleeping for 5 h or less and 9 h or more. Being older and widowed/divorced/separated, high levels of physical activity, pain/discomfort, obesity and high scores on the General Health Questionnaires were associated with sleeping for 5 h or less. Female, being younger and underweight were associated with sleeping for 9 h or more. Alcohol dependence, anxiety disorder and social phobia were associated significantly with sleeping for 5 h or less and 9 h or more. Other psychiatric disorders were more common in subjects who slept for 5 h or less (e.g. alcohol use disorder, mood disorder, major depressive disorder, dysthymic disorder, obsessive-compulsive disorder and specific phobia) or 9 h or more (e.g. post-traumatic stress disorder). In addition, subjects who slept for 5 h or less reported more sleep disturbances than did subjects who slept for 7 h. Short or long sleep is associated with psychiatric disorders and/or sleep disturbance, therefore attention to the mental health of short or long sleepers is needed.

  19. The impact of information and other factors on on-farm agrobiodiversity conservation: evidence from a duration analysis of Portuguese fruit growers

    Energy Technology Data Exchange (ETDEWEB)

    Botelho, A.; Dinis, I.; Costa Pinto, L.

    2012-11-01

    In spite of the increasing awareness of the importance of in situ and on-farm conservation of agro biodiversity, there is still limited knowledge about the factors that influence farmers choices in variety adoption. The purpose of this paper is to contribute to a better understanding of the factors that influence farmers adoption of traditional varieties of fruit trees so that better and more effective policy measures aiming at their preservation can be designed. While studies in this area have mainly employed standard probit/logit techniques, in this paper, an econometric technique which addresses simultaneously the issue of sample censoring and the joint determination of the occurrence and timing of adoptions duration analysis was applied. The use of this technique in the analysis of adoption data uncovers a sizably higher effect of information on farmers decisions than that obtained by standard approaches. The results strongly support the idea that good extension services providing reliable and accessible information, as well as technical guidance adapted to local conditions, are fundamental components in determining the adoption of land races. (Author)

  20. HPV infection, risk factors and viral load among Mexican male college students

    Directory of Open Access Journals (Sweden)

    Carmina Vera-Uehara

    2014-01-01

    Full Text Available Objectives: To determine the prevalence of HPV and the risky sexual behaviors associated to it in a sample of male college students, taking into account genotype and viral load. Methods: From 2002 to 2003, male students from the Autonomous University of Morelos State completed a questionnaire and provided self-collected genital samples to detect and quantify HPV. We performed a bivariate and a multivariate logistic regression analysis to identify correlates associated with the infection and to assess the viral load as a function of the viral infecting type. The fragments of β-globin gene and L1 of HPV, were amplified, purified and cloned, to evaluate viral load. Results: Among 253 subjects, HPV prevalence was 19.4%, and HPV16 was the most common subtype. History of STIs (OR = 4.8; 95% CI 1.2–18.9, contraceptive pill use by female partner (OR = 2.6; 95% CI 1.1–6.3 and exchanging sex for money (OR = 4.9; 95% CI 1.2–20 were associated to the HPV infection. HPV16 viral load was 7.8 copies (HPV/beta-globin compared to 0.9 copies for other HPV types. Discussion: HPV16 displayed the highest viral load, and it was the most prevalent. It was found that using contraceptive pills by female partners was associated with HPV infection.

  1. Enhancement of skin wound healing with decellularized scaffolds loaded with hyaluronic acid and epidermal growth factor

    Energy Technology Data Exchange (ETDEWEB)

    Su, Zhongchun; Ma, Huan; Wu, Zhengzheng [Institute of Biomedicine, National Engineering Research Center of Genetic Medicine, Key Lab for Genetic Medicine of Guangdong Province, Jinan University, Guangzhou 510632 (China); Zeng, Huilan [Department of Hematology, The First Affiliated Hospital, Jinan University, Guangzhou 510632 (China); Li, Zhizhong [Department of Bone, The First Affiliated Hospital, Jinan University, Guangzhou 510632 (China); Wang, Yuechun; Liu, Gexiu [Department of Physiology, School of Medicine, Jinan University, Guangzhou 510632 (China); Xu, Bin; Lin, Yongliang; Zhang, Peng [Grandhope Biotech Co., Ltd., Building D, #408, Guangzhou International Business Incubator, Guangzhou Science Park, Guangzhou 510663, Guangdong (China); Wei, Xing, E-mail: wei70@hotmail.com [Institute of Biomedicine, National Engineering Research Center of Genetic Medicine, Key Lab for Genetic Medicine of Guangdong Province, Jinan University, Guangzhou 510632 (China)

    2014-11-01

    Current therapy for skin wound healing still relies on skin transplantation. Many studies were done to try to find out ways to replace skin transplantation, but there is still no effective alternative therapy. In this study, decellularized scaffolds were prepared from pig peritoneum by a series of physical and chemical treatments, and scaffolds loaded with hyaluronic acid (HA) and epidermal growth factor (EGF) were tested for their effect on wound healing. MTT assay showed that EGF increased NIH3T3 cell viability and confirmed that EGF used in this study was biologically active in vitro. Scanning electron microscope (SEM) showed that HA stably attached to scaffolds even after soaking in PBS for 48 h. ELISA assay showed that HA increased the adsorption of EGF to scaffolds and sustained the release of EGF from scaffolds. Animal study showed that the wounds covered with scaffolds containing HA and EGF recovered best among all 4 groups and had wound healing rates of 49.86%, 70.94% and 87.41% respectively for days 10, 15 and 20 post-surgery compared to scaffolds alone with wound healing rates of 29.26%, 42.80% and 70.14%. In addition, the wounds covered with scaffolds containing EGF alone were smaller than no EGF scaffolds on days 10, 15 and 20 post-surgery. Hematoxylin–Eosin (HE) staining confirmed these results by showing that on days 10, 15 and 20 post-surgery, the thicker epidermis and dermis layers were observed in the wounds covered with scaffolds containing HA and EGF than scaffolds alone. In addition, the thicker epidermis and dermis layers were also observed in the wounds covered with scaffolds containing EGF than scaffolds alone. Skin appendages were observed on day 20 only in the wound covered with scaffolds containing HA and EGF. These results demonstrate that the scaffolds containing HA and EGF can enhance wound healing. - Highlights: • HA can increase the adsorption of EGF to decellularized scaffolds. • HA can sustain the release of EGF from

  2. Perlecan and vascular endothelial growth factor-encoding DNA-loaded chitosan scaffolds promote angiogenesis and wound healing.

    Science.gov (United States)

    Lord, Megan S; Ellis, April L; Farrugia, Brooke L; Whitelock, John M; Grenett, Hernan; Li, Chuanyu; O'Grady, Robert L; DeCarlo, Arthur A

    2017-03-28

    The repair of dermal wounds, particularly in the diabetic population, poses a significant healthcare burden. The impaired wound healing of diabetic wounds is attributed to low levels of endogenous growth factors, including vascular endothelial growth factor (VEGF), that normally stimulate multiple phases of wound healing. In this study, chitosan scaffolds were prepared via freeze drying and loaded with plasmid DNA encoding perlecan domain I and VEGF189 and analyzed in vivo for their ability to promote dermal wound healing. The plasmid DNA encoding perlecan domain I and VEGF189 loaded scaffolds promoted dermal wound healing in normal and diabetic rats. This treatment resulted in an increase in the number of blood vessels and sub-epithelial connective tissue matrix components within the wound beds compared to wounds treated with chitosan scaffolds containing control DNA or wounded controls. These results suggest that chitosan scaffolds containing plasmid DNA encoding VEGF189 and perlecan domain I have the potential to induce angiogenesis and wound healing.

  3. Elastodynamic Stress Intensity Factor History for a Semi-infinite Crack Under Three-dimensional Transient Loading

    Institute of Scientific and Technical Information of China (English)

    李湘平; 柳春图

    1994-01-01

    The dynamic stress intensity factor history for a semi-infinite crack in an otherwise unbounded elastic body is analyzed. The crack is subjected to a pair of suddenly-applied point loadings on its faces at a distance L away from the crack tip. The exact expression for the mode I stress intensity factor as a function of time is obtained. The method of solution is based on the direct application of integral transforms, the Wiener-Hopf technique and the Cagniard-de Hoop method. Due to the existence of the characteristic length in loading, this problem was long believed a knotty problem. Some features of the solutions are discussed and graphical result for numerical computation is presented.

  4. Cost-based Optimal Distributed Generation Planning with Considering Voltage Depended Loads and Power Factor of Distributed Generation

    Directory of Open Access Journals (Sweden)

    Babak Yousefi-Khangah

    2014-12-01

    Full Text Available If determination of location and size of Distributed Generation (DG are applied accurately, the DG’s ability will improve the network situation and reduce operation costs. In this paper, various market conditions are considered to maximize the benefit of DG’s presence and make a trade off among advantages of DG, network situation, and Distribution Company (DISCO owners. To determine the optimal location and size of DG, two methods of the cost minimization and the nodal pricing are combined. In addition to evaluating the impact of parameters such as variation of energy price and load on objective function, effect of these parameters on location and size of DG is considered. To confirm the results, impact of loads which are dependent on voltage and variation of the power factor of the DG units is applied and then effect of power factor on optimal location and size of DG is shown. A method is proposed for convergence of different results which is caused by different power factors. To observe long-term impact of the DG’s presence in the network, a load growth for five years is considered annually. Study is carried out on IEEE30 bus test circuit.

  5. Factors affecting stream nutrient loads: A synthesis of regional SPARROW model results for the continental United States

    Science.gov (United States)

    Preston, Stephen D.; Alexander, Richard B.; Schwarz, Gregory E.; Crawford, Charles G.

    2011-01-01

    We compared the results of 12 recently calibrated regional SPARROW (SPAtially Referenced Regressions On Watershed attributes) models covering most of the continental United States to evaluate the consistency and regional differences in factors affecting stream nutrient loads. The models - 6 for total nitrogen and 6 for total phosphorus - all provide similar levels of prediction accuracy, but those for major river basins in the eastern half of the country were somewhat more accurate. The models simulate long-term mean annual stream nutrient loads as a function of a wide range of known sources and climatic (precipitation, temperature), landscape (e.g., soils, geology), and aquatic factors affecting nutrient fate and transport. The results confirm the dominant effects of urban and agricultural sources on stream nutrient loads nationally and regionally, but reveal considerable spatial variability in the specific types of sources that control water quality. These include regional differences in the relative importance of different types of urban (municipal and industrial point vs. diffuse urban runoff) and agriculture (crop cultivation vs. animal waste) sources, as well as the effects of atmospheric deposition, mining, and background (e.g., soil phosphorus) sources on stream nutrients. Overall, we found that the SPARROW model results provide a consistent set of information for identifying the major sources and environmental factors affecting nutrient fate and transport in United States watersheds at regional and subregional scales. ?? 2011 American Water Resources Association. This article is a U.S. Government work and is in the public domain in the USA.

  6. Modeling and Finite Element Analysis of Load-Carrying Performance of a Wind Turbine Considering the Influence of Assembly Factors

    Directory of Open Access Journals (Sweden)

    Jianmei Wang

    2017-03-01

    Full Text Available In this work, a wind turbine shrink disk is used as the research object to investigate load-carrying performance of a multi-layer interference fit, and the theoretical model and finite element model are constructed. According to those models, a MW-level turbine shrink disk is designed, and a test device is developed to apply torque to this turbine shrink disk by hydraulic jack. Then, the circumferential slip between the contact surfaces is monitored and the slip of all contact surfaces is zero. This conclusion verifies the reasonability of the proposed models. The effect of the key influencing factors, such as machining deviation, assembly clearance and propel stroke, were analyzed. The contact pressure and load torque of the mating surfaces were obtained by building typical models with different parameters using finite element analysis (FEA. The results show that the minimum assembly clearance and the machining deviation within the machining range have little influence on load-carrying performance of multi-layer interference fit, while having a greater influence on the maximum assembly clearance and the propel stroke. The results also show that the load-carrying performance of a multiple-layer interference fit can be ensured only if the key factors are set within a reasonable design range. To avoid the abnormal operation of equipment caused by insufficient load torque, the propel stroke during practical assembly should be at least 0.95 times the designed propel stroke, which is significant in guiding the design and assembly of the multi-layer interference fit.

  7. Edge loading in metal-on-metal hips: low clearance is a new risk factor

    Science.gov (United States)

    Zografos, Angelos; Sayles, Ritchie S; Hart, Alister; Cann, Philippa

    2012-01-01

    The revision rate of large head metal-on-metal and resurfacing hips are significantly higher than conventional total hip replacements. The revision of these components has been linked to high wear caused by edge loading; which occurs when the head–cup contact patch extends over the cup rim. There are two current explanations for this; first, there is loss of entrainment of synovial fluid resulting in breakdown of the lubricating film and second, edge loading results in a large local increase in contact pressure and consequent film thickness reduction at the cup rim, which causes an increase in wear. This paper develops a method to calculate the distance between the joint reaction force vector and the cup rim – the contact patch centre to rim (CPCR) distance. However, the critical distance for the risk of edge loading is the distance from the contact patch edge to rim (CPER) distance. An analysis of explanted hip components, divided into edge worn and non-edge-worn components showed that there was no statistical difference in CPCR values, but the CPER value was significantly lower for edge worn hips. Low clearance hips, which have a more conformal contact, have a larger diameter contact patch and thus are more at risk of edge loading for similarly positioned hips. PMID:22558836

  8. Computer use, sleep duration and health symptoms

    DEFF Research Database (Denmark)

    Nuutinen, Teija; Roos, Eva; Ray, Carola

    2014-01-01

    and Denmark in 2010, including data on 5,402 adolescents (mean age 15.61 (SD 0.37), girls 53 %). Symptoms assessed included feeling low, irritability/bad temper, nervousness, headache, stomachache, backache, and feeling dizzy. We used structural equation modeling to explore the mediating effect of sleep...... duration on the association between computer use and symptom load. RESULTS: Adolescents slept approximately 8 h a night and computer use was approximately 2 h a day. Computer use was associated with shorter sleep duration and higher symptom load. Sleep duration partly mediated the association between...

  9. Assessment of the magnitude of geographical variations in the duration of non-work-related sickness absence by individual and contextual factors

    Directory of Open Access Journals (Sweden)

    Isabel Torá-Rocamora

    2015-05-01

    Conclusions: County-level variation in the duration of NWRSA was small and was explained more by individual than by contextual variables. Knowledge of geographic differences in NWRSA duration is needed to plan specific programs and interventions to minimize these differences.

  10. Determination of Actual Friction Factors in Metal Forming under Heavy Loaded Regimes Combining Experimental and Numerical Analysis

    Directory of Open Access Journals (Sweden)

    Ana María Camacho

    2016-09-01

    Full Text Available Tribological conditions can change drastically during heavy loaded regimes as experienced in metal forming; this is especially critical when lubrication can only be applied at the early stage of the process because the homogeneous lubricant layer can break along the die-workpiece interface. In these cases, adopting a constant friction factor for the lubricant-surface pair may not be a valid assumption. This paper presents a procedure based on the use of dual friction factor maps to determine friction factors employed in heavy loaded regimes. A finite element (FE simulation is used to obtain the friction factor map for the alloy UNS A96082. Experiments were conducted using four lubricants (aluminum anti-size, MoS2 grease, silicone oil, and copper paste to determine the actual friction curves. The experimental procedure is based on the application of lubricant only at the beginning of the first stage of ring compression, and not at intermediate stages as is usual in typical ring compression tests (RCTs. The results show that for small reductions (rh < 20%, the conventional RCT can be applied because the tribological conditions remain similar. For large reductions (rh > 20%, it is recommended to obtain an average value of the friction factor for every lubricant-surface pair in the range of deformation considered.

  11. The effect of some ecological factors on the intestinal parasite loads of the Asian elephant (Elephas maximus) in southern India.

    Science.gov (United States)

    Vidya, T N C; Sukumar, R

    2002-09-01

    Some ecological factors that might potentially influence intestinal parasite loads in the Asian elephant (Elephas maximus Linn.) were investigated in the Nilgiris, southern India. Fresh dung samples from identified animals were analysed, and the number of eggs/g of dung used as an index of parasite load. Comparisons across seasons and habitats revealed that parasite loads were significantly higher during the dry season than the wet season, but were not different between the dry-deciduous and dry-thorn forests in either season. After accounting for the effect of age on body condition, there was no correlation between body condition, assessed visually using morphological criteria, and parasite load in either season. Individuals of different elephant herds were not characterized by distinct parasite communities in either season. When intra-individual variation was examined, samples collected from the same individual within a day differed significantly in egg densities, while the temporal variation over several weeks or months (within a season) was much less. Egg densities within dung piles were uniform, enabling a simpler collection method henceforth.

  12. The effect of some ecological factors on the intestinal parasite loads of the Asian elephant (Elephas maximus) in southern India

    Indian Academy of Sciences (India)

    T N C Vidya; R Sukumar

    2002-09-01

    Some ecological factors that might potentially influence intestinal parasite loads in the Asian elephant (Elephas maximus Linn.) were investigated in the Nilgiris, southern India. Fresh dung samples from identified animals were analysed, and the number of eggs/g of dung used as an index of parasite load. Comparisons across seasons and habitats revealed that parasite loads were significantly higher during the dry season than the wet season, but were not different between the dry-deciduous and dry-thorn forests in either season. After accounting for the effect of age on body condition, there was no correlation between body condition, assessed visually using morphological criteria, and parasite load in either season. Individuals of different elephant herds were not characterized by distinct parasite communities in either season. When intra-individual variation was examined, samples collected from the same individual within a day differed significantly in egg densities, while the temporal variation over several weeks or months (within a season) was much less. Egg densities within dung piles were uniform, enabling a simpler collection method henceforth.

  13. Role of insulin-like growth factor-I in the regulation of skeletal muscle adaptation to increased loading

    Science.gov (United States)

    Adams, G. R.

    1998-01-01

    Adaptations in muscle mass stimulated by changes in muscle loading state entail alternations in the synthesis and degradation of myofiber proteins and the modulation of myonuclear number such that the ratio between the number of myonuclei and the size of the myofibers remains relatively constant. As depicted schematically in Figure 2.6, the literature regarding the role of IGF-in mediating muscle adaptation to alterations in loading state suggests the following conclusions: During periods of increased loading, myofibers upregulate the expression and secretion of IGF-I. Acting as an autocrine and/or paracrine growth factor, IGF-I stimulates myofiber anabolic processes. Acting as a paracrine growth factor, IGF-I also stimulates adjacent satellite cells to enter the cell cycle and proliferate. Continued myofiber production of IGF-I stimulates some satellite cells to differentiate and then fuse with myofibers, thus providing additional myonuclei in order to maintain or reestablish the myonucleus to myofiber size ratios of the enlarged myofibers.

  14. Role of insulin-like growth factor-I in the regulation of skeletal muscle adaptation to increased loading

    Science.gov (United States)

    Adams, G. R.

    1998-01-01

    Adaptations in muscle mass stimulated by changes in muscle loading state entail alternations in the synthesis and degradation of myofiber proteins and the modulation of myonuclear number such that the ratio between the number of myonuclei and the size of the myofibers remains relatively constant. As depicted schematically in Figure 2.6, the literature regarding the role of IGF-in mediating muscle adaptation to alterations in loading state suggests the following conclusions: During periods of increased loading, myofibers upregulate the expression and secretion of IGF-I. Acting as an autocrine and/or paracrine growth factor, IGF-I stimulates myofiber anabolic processes. Acting as a paracrine growth factor, IGF-I also stimulates adjacent satellite cells to enter the cell cycle and proliferate. Continued myofiber production of IGF-I stimulates some satellite cells to differentiate and then fuse with myofibers, thus providing additional myonuclei in order to maintain or reestablish the myonucleus to myofiber size ratios of the enlarged myofibers.

  15. Calculation of load increase factors for assessment of progressive collapse potential in framed steel structures

    OpenAIRE

    Osama Ahmed Mohamed

    2015-01-01

    Progressive collapse of building structures is a relatively rare event. However, the consequences of progressive collapse may be catastrophic in terms of injuries and loss of lives. In addition, in many parts of the world including the United States of America, Europe, Asia, and recently, United Arab Emirates, there is a trend to build taller and more structurally complicated buildings with adventurous load paths. Therefore, structural design that takes into account the potential for progress...

  16. Effects of a low-glycemic load diet on resting energy expenditure and heart disease risk factors during weight loss.

    Science.gov (United States)

    Pereira, Mark A; Swain, Janis; Goldfine, Allison B; Rifai, Nader; Ludwig, David S

    2004-11-24

    Weight loss elicits physiological adaptations relating to energy intake and expenditure that antagonize ongoing weight loss. To test whether dietary composition affects the physiological adaptations to weight loss, as assessed by resting energy expenditure. DESIGN, STUDY, AND PARTICIPANTS: A randomized parallel-design study of 39 overweight or obese young adults aged 18 to 40 years who received an energy-restricted diet, either low-glycemic load or low-fat. Participants were studied in the General Clinical Research Centers of the Brigham and Women's Hospital and the Children's Hospital, Boston, Mass, before and after 10% weight loss. The study was conducted from January 4, 2001, to May 6, 2003. Resting energy expenditure measured in the fasting state by indirect calorimetry, body composition by dual-energy x-ray absorptiometry, cardiovascular disease risk factors, and self-reported hunger. Resting energy expenditure decreased less with the low-glycemic load diet than with the low-fat diet, expressed in absolute terms (mean [SE], 96 [24] vs 176 [27] kcal/d; P = .04) or as a proportion (5.9% [1.5%] vs 10.6% [1.7%]; P = .05). Participants receiving the low-glycemic load diet reported less hunger than those receiving the low-fat diet (P = .04). Insulin resistance (P = .01), serum triglycerides (P = .01), C-reactive protein (P = .03), and blood pressure (P = .07 for both systolic and diastolic) improved more with the low-glycemic load diet. Changes in body composition (fat and lean mass) in both groups were very similar (P = .85 and P = .45, respectively). Changes in dietary composition within prevailing norms can affect physiological adaptations that defend body weight. Reduction in glycemic load may aid in the prevention or treatment of obesity, cardiovascular disease, and diabetes mellitus.

  17. Intra-individual reaction time variability in mild cognitive impairment and Alzheimer's disease: gender, processing load and speed factors.

    Directory of Open Access Journals (Sweden)

    Michelle Phillips

    Full Text Available Compared to cognitively healthy ageing (CH, intra-individual variability in reaction time (IIV(RT, a behavioural marker of neurological integrity, is commonly reported to increase in both Alzheimer's disease (AD and mild cognitive impairment (MCI. It varies in MCI with respect to whether it represents the pro-dromal stages of dementia or not; being greatest in those most likely to convert. Abnormal IIV(RT in MCI therefore represents a potential measure of underlying functional integrity that may serve to differentiate MCI from CH and to help identify those patients for whom MCI is the result of a progressive pathological process. As the clinical approach to MCI is increasingly stratified with respect to gender, we investigated whether this factor could influence study outcome. The influence of RTSPEED and processing load upon IIV(RT was also examined. Under low processing load conditions, IIV(RT was significantly increased in both MCI and AD compared to CH. However, correcting for an individual's processing speed abolished this effect in MCI but not in AD, indicating that the increased IIV(RT in MCI and AD may result from different factors. In MCI but not in CH, IIV(RT was significantly greater for females. Increasing task processing load by adding distracting information, although increasing overall IIV(RT, failed to improve the differentiation between CH and both MCI and AD, and in MCI resulted in a reduction in the influence of gender upon study outcome. The outcome of studies investigating IIV(RT in MCI and AD compared to CH therefore appear influenced by the gender of the participants, by task-related processing load and processing speed.

  18. Dextran-based hydrogel containing chitosan microparticles loaded with growth factors to be used in wound healing

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, M.P. [CICS-UBI, Health Sciences Research Center, Faculty of Health Sciences, University of Beira Interior, Covilhã (Portugal); UDI-IPG, Research Unit for Inland Development, Polytechnic Institute of Guarda, Guarda (Portugal); Morgado, P.I.; Miguel, S.P. [CICS-UBI, Health Sciences Research Center, Faculty of Health Sciences, University of Beira Interior, Covilhã (Portugal); Coutinho, P. [CICS-UBI, Health Sciences Research Center, Faculty of Health Sciences, University of Beira Interior, Covilhã (Portugal); UDI-IPG, Research Unit for Inland Development, Polytechnic Institute of Guarda, Guarda (Portugal); Correia, I.J., E-mail: icorreia@ubi.pt [CICS-UBI, Health Sciences Research Center, Faculty of Health Sciences, University of Beira Interior, Covilhã (Portugal)

    2013-07-01

    Skin injuries are traumatic events, which are seldom accompanied by complete structural and functional restoration of the original tissue. Different strategies have been developed in order to make the wound healing process faster and less painful. In the present study in vitro and in vivo assays were carried out to evaluate the applicability of a dextran hydrogel loaded with chitosan microparticles containing epidermal and vascular endothelial growth factors, for the improvement of the wound healing process. The carriers' morphology was characterized by scanning electron microscopy. Their cytotoxicity profile and degradation by-products were evaluated through in vitro assays. In vivo experiments were also performed to evaluate their applicability for the treatment of skin burns. The wound healing process was monitored through macroscopic and histological analysis. The macroscopic analysis showed that the period for wound healing occurs in animals treated with microparticle loaded hydrogels containing growth factors that were considerably smaller than that of control groups. Moreover, the histological analysis revealed the absence of reactive or granulomatous inflammatory reaction in skin lesions. The results obtained both in vitro and in vivo disclosed that these systems and its degradation by-products are biocompatible, contributed to the re-establishment of skin architecture and can be used in a near future for the controlled delivery of other bioactive agents used in regenerative medicine. - Highlights: • Evaluation of a hydrogel loaded with microparticles containing growth factors for wound healing • In vitro and in vivo assays were performed to characterize the properties of the skin substitute. • The monitoring of the wound healing process was done by macroscopic and histological analysis.

  19. Biomechanical factors related to occlusal load transfer in removable complete dentures.

    Science.gov (United States)

    Żmudzki, Jarosław; Chladek, Grzegorz; Kasperski, Jacek

    2015-08-01

    Owing to economic conditions, removable dentures remain popular despite the discomfort and reduced chewing efficiency experienced by most denture wearers. However, there is little evidence to confirm that the level of mucosal load exceeds the pressure pain threshold. This discrepancy stimulated us to review the current state of knowledge on the biomechanics of mastication with complete removable dentures. The loading beneath dentures was analyzed in the context of denture foundation characteristics, salivary lubrication, occlusal forces, and the biomechanics of mastication. The analysis revealed that the interpretation of data collected in vivo is hindered due to the simultaneous overlapping effects of many variables. In turn, problems with determining the pressure beneath a denture and analyzing frictional processes constitute principal limitations of in vitro model studies. Predefined conditions of finite element method simulations should include the effects of oblique mastication forces, simultaneous detachment and sliding of the denture on its foundation, and the stabilizing role of balancing contacts. This review establishes that previous investigations may have failed because of their unsubstantiated assumption that, in a well-working balanced occlusion, force is only exerted perpendicular to the occlusal plane, allowing the denture to sit firmly on its foundation. Recent improvements in the simulation of realistic biomechanical denture behavior raise the possibility of assessing the effects of denture design on the pressures and slides beneath the denture.

  20. Factors Affecting P Loads to Surface Waters: Comparing the Roles of Precipitation and Land Management Practices

    Science.gov (United States)

    Motew, M.; Booth, E.; Carpenter, S. R.; Kucharik, C. J.

    2014-12-01

    Surface water quality is a major concern in the Yahara watershed (YW) of southern Wisconsin, home to a thriving dairy industry, the city of Madison, and five highly valued lakes that are eutrophic. Despite management interventions to mitigate runoff, there has been no significant trend in P loading to the lakes since 1975. Increases in manure production and heavy rainfall events over this time period may have offset any effects of management. We developed a comprehensive, integrated modeling framework that can simulate the effects of multiple drivers on ecosystem services, including surface water quality. The framework includes process-based representation of terrestrial ecosystems (Agro-IBIS) and groundwater flow (MODFLOW), hydrologic routing of water and nutrients across the landscape (THMB), and assessment of lake water quality (YWQM). Biogeochemical cycling and hydrologic transport of P have been added to the framework to enable detailed simulation of P dynamics within the watershed, including interactions with climate and management. The P module features in-soil cycling of organic, inorganic, and labile forms of P; manure application, decomposition, and subsequent loss of dissolved P in runoff; loss of particulate-bound P with erosion; and transport of dissolved and particulate P within waterways. Model results will compare the effects of increased heavy rainfall events, increased manure production, and implementation of best management practices on P loads to the Yahara lakes.

  1. Repair effect of diabetic ulcers with recombinant human epidermal growth factor loaded by sustained-release microspheres

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In this study the w/o/w extraction–evaporation technique was adopted to prepare poly(lactic-co-glycolic acid) (PLGA) microspheres loading recombinant human epidermal growth factor (rhEGF). The micro-spheres were characterized for morphology by transmission electron microscopy (TEM) and particle size distribution. The release performances, the proliferation effects and therapeutic effects of rhEGF-loaded PLGA microspheres were all studied. The results showed that these spherical micro-spheres had a narrow size distribution and a high drug encapsulation efficiency (85.6%). RhEGF-loaded microspheres enhanced the growth rate of fibroblasts and wound healing more efficiently than pure rhEGF. The number of the proliferating cell nuclear antigen (PCNA) in the epidermis layer with the mi-crosphere treatment was significantly larger than those of the control groups. Overall locally sustained delivery of rhEGF from biodegradable PLGA microspheres may serve as a novel therapeutic strategy for diabetic ulcer repair.

  2. Modified panel data regression model and its applications to the airline industry: Modeling the load factor of Europe North and Europe Mid Atlantic flights

    Directory of Open Access Journals (Sweden)

    Yohannes Yebabe Tesfay

    2016-08-01

    Full Text Available This article conducts a stochastic analysis on the passenger load factor of the airline industry. Used to measure competence and performance of the airline, load factor is the percentage of seats filled by revenue passengers. It is considered a complex metric in the airline industry. Thus, it is affected by several dynamic factors. This paper applies advanced stochastic models to obtain the best fitted trend of load factor for Europe's North Atlantic (NA and Mid Atlantic (MA flights in the Association of European Airlines. The stochastic model's fit helps to forecast the load factor of flights within these geographical regions and evaluate the airline's demand and capacity management. The paper applies spectral density estimation and dynamic time effects panel data regression models on the monthly load factor flights of NA and MA from 1991 to 2013. The results show that the load factor has both periodic and serial correlations. Consequently, the author acknowledges that the use of an ordinal panel data model is inappropriate for a realistic econometric model of load factor. Therefore, to control the periodic correlation structure, the author modified the existing model was modified by introducing dynamic time effects. Moreover, to eradicate serial correlation, the author applied the Prais–Winsten methodology was applied to fit the model. In this econometric analysis, the study finds that AEA airlines have greater demand and capacity management for both NA and MA flights. In conclusion, this study prosperous in finding an effective and efficient dynamic time effects panel data regression model fit, which empowers engineers to forecast the load factor off AEA airlines.

  3. Factors associated to the duration of exclusive breastfeeding Factores asociados con la duración de la lactancia materna exclusiva Fatores associados com a duração da lactância materna exclusiva

    Directory of Open Access Journals (Sweden)

    Jhon Henry Osorio Castaño

    2012-08-01

    Full Text Available Objective. To identify the scientific evidence available on factors associated to the duration of exclusive breastfeeding. Methodology. A systematic review without meta-analysis was performed. An electronic search strategy was conducted of primary articles published in Medline, Lilacs, Scielo, and Ovid from 1990 to 2010 in English, Spanish, and Portuguese. Observational and intervention studies were included, which sought to identify factors associated to the duration of exclusive breastfeeding for at least three months. Results. Some 195 studies were identified, but only 18 complied with the inclusion and quality criteria. A total of 66.6% measured the prevalence of breastfeeding up to six months. Fifty percent reported the use of a pacifier or baby bottle as the negative factor that most affects the duration of exclusive breastfeeding. Some 44.4% mentioned as positive factors in the duration of exclusive breastfeeding: high levels of schooling, multiparity, exposure to a breastfeeding program, and low family income. Conclusion. Literature available provides information on the factors associated to the duration of exclusive breastfeeding, although the methodological heterogeneity of the studies did not permit evaluating the scientific evidence of the results discussed.Objetivo. Identificar la evidencia científica disponible acerca de los factores asociados a la duración de la lactancia materna exclusiva. Metodología. Revisión sistemática sin meta-análisis. Se realizó estrategia de búsqueda electrónica de artículos primarios publicados en Medline, Lilacs, Scielo y Ovid desde 1990 hasta 2010 en idioma inglés, español y portugués. Se incluyeron estudios observacionales y de intervención que buscaran identificar factores asociados a la duración de la lactancia materna exclusiva como mínimo por tres meses. Resultados. Se identificaron 195 estudios, pero solo 18 cumplieron con los criterios de inclusión y de calidad. El 66.6% realiz

  4. Family load estimates and risk factors of anxiety disorders in a nationwide three generation study

    DEFF Research Database (Denmark)

    Helenius, Dorte; Munk-Jørgensen, Povl; Steinhausen, Hans-Christoph

    2014-01-01

    The present study investigated how often anxiety disorders with different ages of onset occurred in affected families compared to control families. Furthermore, the study addressed the impact of sex, region of residence, year and month of birth, and parental age at birth. The sample included N=1373...... child and adolescent psychiatric participants born between 1952 and 2000 and registered in the Danish Psychiatric Central Register (DPCR) who developed an anxiety disorder before the age of 18. N =4019 controls without any psychiatric diagnosis before age 18, were matched for age, sex, and residential...... region. Psychiatric diagnoses were also obtained for parents, siblings, and offspring. A family load component was obtained by using various mixed regression models. Anxiety disorders occurred significantly more often in case than in control families. Having a mother, father, or a sibling...

  5. Estimating duration intervals

    NARCIS (Netherlands)

    Ph.H.B.F. Franses (Philip Hans); B.L.K. Vroomen (Björn)

    2003-01-01

    textabstractDuration intervals measure the dynamic impact of advertising on sales. More precise, the p per cent duration interval measures the time lag between the advertising impulse and the moment that p per cent of its effect has decayed. In this paper, we derive an expression for the duration

  6. Associations of sleep disturbance and duration with metabolic risk factors in obese persons with type 2 diabetes: data from the Sleep AHEAD Study

    Directory of Open Access Journals (Sweden)

    St-Onge MP

    2012-12-01

    and provided a fasting blood sample. Regression analyses estimated the relationship between sleep variables and metabolic risk factors. Models were adjusted for study center, age, sex, race/ethnicity, waist circumference, smoking, alcohol intake, diabetes duration, and relevant medications.Results: Of 60 associations tested, only one was significant: fasting glucose was associated with sleep efficiency (estimate −0.53 ± [standard error] 0.26, P = 0.041. No associations were found between any of the sleep variables and lipid profile or hemoglobin A1c.Conclusions: The present data show only weak associations between select sleep variables and metabolic risk factors and do not provide strong support for a role of sleep on metabolic abnormalities in obese patients with type 2 diabetes.Keywords: obesity, obstructive sleep apnea, metabolic risk, sleep, diabetes

  7. The prediction of the impact of climatic factors on short-term electric power load based on the big data of smart city

    Science.gov (United States)

    Qiu, Yunfei; Li, Xizhong; Zheng, Wei; Hu, Qinghe; Wei, Zhanmeng; Yue, Yaqin

    2017-08-01

    The climate changes have great impact on the residents’ electricity consumption, so the study on the impact of climatic factors on electric power load is of significance. In this paper, the effects of the data of temperature, rainfall and wind of smart city on short-term power load is studied to predict power load. The authors studied the relation between power load and daily temperature, rainfall and wind in the 31 days of January of one year. In the research, the authors used the Matlab neural network toolbox to establish the combinational forecasting model. The authors trained the original input data continuously to get the internal rules inside the data and used the rules to predict the daily power load in the next January. The prediction method relies on the accuracy of weather forecasting. If the weather forecasting is different from the actual weather, we need to correct the climatic factors to ensure accurate prediction.

  8. Epidemiological evidence for work load as a risk factor for osteoarthritis of the hip: a systematic review.

    Directory of Open Access Journals (Sweden)

    Sandra I Sulsky

    Full Text Available OBJECTIVE: Osteoarthritis of the hip (OA is a common degenerative disorder of the joint cartilage that presents a major public health problem worldwide. While intrinsic risk factors (e.g, body mass and morphology have been identified, external risk factors are not well understood. In this systematic review, the evidence for workload as a risk factor for hip OA is summarized and used to derive recommendations for prevention and further research. METHODS: Epidemiological studies on workload or occupation and osteoarthritis of the hip were identified through database and bibliography searches. Using pre-defined quality criteria, 30 studies were selected for critical evaluation; six of these provided quantitative exposure data. RESULTS: Study results were too heterogeneous to develop pooled risk estimates by specific work activities. The weight of evidence favors a graded association between long-term exposure to heavy lifting and risk of hip OA. Long-term exposure to standing at work might also increase the risk of hip OA. CONCLUSIONS: It is not possible to estimate a quantitative dose-response relationship between workload and hip OA using existing data, but there is enough evidence available to identify job-related heavy lifting and standing as hazards, and thus to begin developing recommendations for preventing hip OA by limiting the amount and duration of these activities. Future research to identify specific risk factors for work-related hip OA should focus on implementing rigorous study methods with quantitative exposure measures and objective diagnostic criteria.

  9. The estimation of uniaxial compressive strength conversion factor of trona and interbeds from point load tests and numerical modeling

    Science.gov (United States)

    Ozturk, H.; Altinpinar, M.

    2017-07-01

    The point load (PL) test is generally used for estimation of uniaxial compressive strength (UCS) of rocks because of its economic advantages and simplicity in testing. If the PL index of a specimen is known, the UCS can be estimated using conversion factors. Several conversion factors have been proposed by various researchers and they are dependent upon the rock type. In the literature, conversion factors on different sedimentary, igneous and metamorphic rocks can be found, but no study exists on trona. In this study, laboratory UCS and field PL tests were carried out on trona and interbeds of volcano-sedimentary rocks. Based on these tests, PL to UCS conversion factors of trona and interbeds are proposed. The tests were modeled numerically using a distinct element method (DEM) software, particle flow code (PFC), in an attempt to guide researchers having various types of modeling problems (excavation, cavern design, hydraulic fracturing, etc.) of the abovementioned rock types. Average PFC parallel bond contact model micro properties for the trona and interbeds were determined within this study so that future researchers can use them to avoid the rigorous PFC calibration procedure. It was observed that PFC overestimates the tensile strength of the rocks by a factor that ranges from 22 to 106.

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

    Science.gov (United States)

    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) PM2.5 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.

  11. Oral vaccination of brushtail possums with BCG: Investigation into factors that may influence vaccine efficacy and determination of duration of protection.

    Science.gov (United States)

    Buddle, B M; Aldwell, F E; Keen, D L; Parlane, N A; Hamel, K L; de Lisle, G W

    2006-10-01

    To determine factors that may influence the efficacy of an oral pelleted vaccine containing Mycobacterium bovis bacille Calmette-Guérin (BCG) to induce protection of brushtail possums against tuberculosis. To determine the duration of protective immunity following oral administration of BCG. In Study 1, a group of possums (n=7) was immunised by feeding 10 pellets containing dead Pasteur BCG, followed 15 weeks later with a single pellet of live Pasteur BCG. At that time, four other groups of possums (n=7 per group) were given a single pellet of live Pasteur BCG orally, a single pellet of live Danish BCG orally, 10 pellets of live Pasteur BCG orally, or a subcutaneous injection of live Pasteur BCG. For the oral pelleted vaccines, BCG was formulated into a lipid matrix, and each pellet contained approximately 107 colony forming units (cfu) of BCG, while the vaccine injected subcutaneously contained 106 cfu of BCG. A sixth, non-vaccinated, group (n=7) served as a control. All possums were challenged by the aerosol route with a low dose of virulent M. bovis 7 weeks after vaccination, and killed 7-8 weeks after challenge. Protection against challenge with M. bovis was assessed from pathological and bacteriological findings. In Study 2, lipid-formulated live Danish BCG was administered orally to three groups of possums (10-11 per group), and these possums were challenged with virulent M. bovis 8, 29 or 54 weeks later. The possums were killed 7 weeks after challenge, to assess protection in comparison to a non-vaccinated group. The results from Study 1 showed that vaccine efficacy was not adversely affected by feeding dead BCG prior to live BCG. Feeding 10 vaccine pellets induced a level of protection similar to feeding a single pellet. Protection was similar when feeding possums a single pellet containing the Pasteur or Danish strains of BCG. All vaccinated groups had significantly reduced pathological changes or bacterial counts when compared to the non-vaccinated group

  12. Uniqueness conditions for constrained three-way factor decompositions with linearly dependent loadings

    NARCIS (Netherlands)

    Stegeman, Alwin; De Almeida, Andre L. F.

    2009-01-01

    In this paper, we derive uniqueness conditions for a constrained version of the parallel factor (Parafac) decomposition, also known as canonical decomposition (Candecomp). Candecomp/Parafac (CP) decomposes a three-way array into a prespecified number of outer product arrays. The constraint is that

  13. Associations between Dietary Acid-Base Load and Cardiometabolic Risk Factors in Adults: The Tehran Lipid and Glucose Study

    Directory of Open Access Journals (Sweden)

    Zahra Bahadoran

    2015-06-01

    Full Text Available BackgroundIn this study we investigated the associations of dietary acid-base load, identified by potential renal acid load (PRAL and protein to potassium (Pro:K ratio, with cardiometabolic risk factors in Tehranian adults.MethodsA cross-sectional study was conducted within the framework of the fourth phase of the Tehran Lipid and Glucose Study (2009 to 2011 on 5,620 men and women aged 19 to 70 years. Dietary data were collected by a trained dietitian using a validated, 147-food item, semi-quantitative food frequency questionnaire, and dietary PRAL and Pro:K ratio were calculated. Multiple linear regression models with adjustment for potential confounding variables were used to evaluate the associations of dietary acid-base load with anthropometric measures, blood pressure, serum triglycerides, high density lipoprotein cholesterol (HDL-C, serum creatinine, and fasting blood glucose.ResultsThe mean±SD age of the participants was 39.8±12.8 years and 54% of participants were women. Mean±SD PRAL was -22.0±29.1; mean PRAL was -15.6 in men and -26.8 in women. Dietary PRAL was associated with weight (β=0.098, P<0.001, waist circumference (β=0.062, P<0.01, serum triglycerides (β=0.143, P<0.01, HDL-C (β=-0.11, P<0.01, diastolic blood pressure (β=0.062, P<0.01, and serum creatinine (β=0.142, P<0.001. Pro:K ratio was associated with weight (β=0.055, P<0.001, waist circumference (β=0.04, P<0.01, serum HDL-C (β=-0.06, P<0.01, serum triglycerides (β=0.03, P<0.05, diastolic blood pressure (β=0.026, P<0.05, and serum creatinine (β=0.07, P<0.01.ConclusionA more acidic dietary acid-base load may be a risk factor for the development of metabolic disorders.

  14. Lower glycemic load meals reduce diurnal glycemic oscillations in women with risk factors for gestational diabetes

    Science.gov (United States)

    Kizirian, Nathalie V; Goletzke, Janina; Brodie, Shannon; Atkinson, Fiona S; Markovic, Tania P; Ross, Glynis P; Buyken, Anette; Brand-Miller, Jennie P

    2017-01-01

    Objective Maternal glycemia plays a key role in fetal growth. We hypothesized that lower glycemic load (GL) meals (lower glycemic index, modestly lower carbohydrate) would substantially reduce day-long glucose variability in women at risk of gestational diabetes mellitus (GDM). Research design and methods A crossover study of 17 women (mean±SD age 34.8±4 years; gestational weeks 29.3±1.3; body mass index 23.8±4.7 kg/m2) who consumed a low GL or a high GL diet in random order, 1-day each, over 2 consecutive days. Diets were energy-matched and fiber-matched with 5 meals per 24 hours. All food was provided. Continuous glucose monitoring was used to assess diurnal glycemia. Results Maternal glucose levels were 51% lower on the low GL day with lower incremental area under the curve (iAUC±SEM 549±109 vs 1120±198 mmol/L min, p=0.015). Glycemic variability was significantly lower on the low GL day, as demonstrated by a lower average SD (0.7±0.1 vs 0.9±0.1, p<0.001) and lower mean amplitude of glycemic excursions (2.1±0.2 vs 2.7±0.2 mmol/L, p<0.001). Conclusions A lower GL meal plan in pregnancy acutely halves day-long maternal glucose levels and reduces glucose variability, providing further evidence to support the utility of a low GL diet in pregnancy. PMID:28405345

  15. Repair of peripheral nerve defects with chemically extracted acellular nerve allografts loaded with neurotrophic factors-transfected bone marrow mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    Yan-ru Zhang; Ka Ka; Ge-chen Zhang; Hui Zhang; Yan Shang; Guo-qiang Zhao; Wen-hua Huang

    2015-01-01

    Chemically extracted acellular nerve allografts loaded with brain-derived neurotrophic fac-tor-transfected or ciliary neurotrophic factor-transfected bone marrow mesenchymal stem cells have been shown to repair sciatic nerve injury better than chemically extracted acellular nerve allografts alone, or chemically extracted acellular nerve allografts loaded with bone marrow mesenchymal stem cells. We hypothesized that these allografts compounded with both brain-derived neurotrophic factor- and ciliary neurotrophic factor-transfected bone marrow mesenchymal stem cells may demonstrate even better effects in the repair of peripheral nerve injury. We cultured bone marrow mesenchymal stem cells expressing brain-derived neuro-trophic factor and/or ciliary neurotrophic factor and used them to treat sciatic nerve injury in rats. We observed an increase in sciatic functional index, triceps wet weight recovery rate, myelin thickness, number of myelinated nerve ifbers, amplitude of motor-evoked potentials and nerve conduction velocity, and a shortened latency of motor-evoked potentials when al-lografts loaded with both neurotrophic factors were used, compared with allografts loaded with just one factor. Thus, the combination of both brain-derived neurotrophic factor and cili-ary neurotrophic factor-transfected bone marrow mesenchymal stem cells can greatly improve nerve injury.

  16. Discounted Duration Calculus

    DEFF Research Database (Denmark)

    Ody, Heinrich; Fränzle, Martin; Hansen, Michael Reichhardt

    2016-01-01

    To formally reason about the temporal quality of systems discounting was introduced to CTL and LTL. However, these logic are discrete and they cannot express duration properties. In this work we introduce discounting for a variant of Duration Calculus. We prove decidability of model checking...... for a useful fragment of discounted Duration Calculus formulas on timed automata under mild assumptions. Further, we provide an extensive example to show the usefulness of the fragment....

  17. Factors affecting the stability of drug-loaded polymeric micelles and strategies for improvement

    Science.gov (United States)

    Zhou, Weisai; Li, Caibin; Wang, Zhiyu; Zhang, Wenli; Liu, Jianping

    2016-09-01

    Polymeric micelles (PMs) self-assembled by amphiphilic block copolymers have been used as promising nanocarriers for tumor-targeted delivery due to their favorable properties, such as excellent biocompatibility, prolonged circulation time, favorable particle sizes (10-100 nm) to utilize enhanced permeability and retention effect and the possibility for functionalization. However, PMs can be easily destroyed due to dilution of body fluid and the absorption of proteins in system circulation, which may induce drug leakage from these micelles before reaching the target sites and compromise the therapeutic effect. This paper reviewed the factors that influence stability of micelles in terms of thermodynamics and kinetics consist of the critical micelle concentration of block copolymers, glass transition temperature of hydrophobic segments and polymer-polymer and polymer-cargo interaction. In addition, some effective strategies to improve the stability of micelles were also summarized.

  18. Acellular biological tissues containing inherent glycosaminoglycans for loading basic fibroblast growth factor promote angiogenesis and tissue regeneration.

    Science.gov (United States)

    Lai, Po-Hong; Chang, Yen; Chen, Sung-Ching; Wang, Chung-Chi; Liang, Huang-Chien; Chang, Wei-Chun; Sung, Hsing-Wen

    2006-09-01

    It was found in our previous study that acellular tissues derived from bovine pericardia consist primarily of insoluble collagen, elastin, and tightly bound glycosaminoglycans (GAGs). It is speculated that the inherent GAGs in acellular tissues may serve as a reservoir for loading basic fibroblast growth factor (bFGF) and promote angiogenesis and tissue regeneration. This study was therefore designed to investigate effects of the content of GAGs in acellular bovine pericardia on the binding of bFGF and its release profile in vitro while its stimulation in angiogenesis and tissue regeneration in vivo were evaluated subcutaneously in a rat model. To control the content of GAGs, acellular tissues were treated additionally with hyaluronidase for 1 (Hase-D1), 3 (Hase-D3), or 5 days (Hase-D5). The in vitro results indicated that a higher content of GAGs in the acellular tissue resulted in an increase in bFGF binding and in a more gradual and sustained release of the growth factor. The in vivo results obtained at 1 week postoperatively showed that the density and the depth of neo-vessels infiltrated into the acellular tissue loaded with bFGF (acellular/bFGF) were significantly greater than the other test samples. At 1 month postoperatively, vascularized neo-connective tissues were found to fill the pores within each test sample, particularly for the acellular/bFGF tissue. These results suggested that the sustained release of bFGF from the acellular/ bFGF tissue continued to be effective in enhancing angiogenesis and generation of new tissues. In conclusion, the inherent GAGs present in acellular tissues may be used for binding and sustained release of bFGF to enhance angiogenesis and tissue regeneration.

  19. Usual dietary glycemic load is associated with cardiometabolic risk factors in physically active Brazilian middle-aged men

    Directory of Open Access Journals (Sweden)

    Paula G. Cocate

    2014-02-01

    Full Text Available Introduction: The effects of dietary glycemic load (GL on cardiometabolic risk factors in physically active subjects are not completely known. Objective: This cross-sectional study assessed the association of habitual dietary GL with cardiometabolic risk factors in physically active Brazilian middle-aged men. Methods: One-hundred seventy-six subjects (Age: 50.6 ± 5.0 years, BMI: 25.5 ± 3.6 kg/m² were evaluated. Anthropometry, lifestyle features, insulin resistance, oxidative stress biomarkers (8-iso-prostaglandin F2α; 8-iso-PGF2α and 8-hydroxydeoxyguanosine; 8-OHdG and lipid profile were assessed. Dietary intake was estimated through a quantitative food frequency questionnaire. Results: The dietary GL was positively associated with free fatty acid concentrations (β = 0.311, r² = 0.13, P-value = 0.034 and triglycerides/HDL cholesterol ratio (β = 0.598, r² = 0.19, P-value = 0.028 regardless of confounding factors (central obesity, red meat consumption, age and energy intake. The oxidative stress biomarker, 8-OHdG, was associated with habitual dietary GL (β = 0.432, r² = 0.11, P-value = 0.004, regardless of previous confounding factors plus excessive alcohol consumption, iron intake and current smoking status. Conclusions: The dietary GL was positively associated with lipid profile (free fatty acid concentrations and triglycerides/HDL cholesterol ratio and oxidative stress biomarker (8-OHdG. These results indicate potential harmfulness of diet with higher GL to cardiometabolic risk factors in middle-aged men, even in physically active individuals.

  20. Influence factors of salt-sensitive hypertension and responses of blood pressure and urinary sodium and potassium excretion to acute oral saline loading among essential hypertensive patients

    Institute of Scientific and Technical Information of China (English)

    刘叶舟

    2014-01-01

    Objective To explore the influence factors of saltsensitive hypertension and to observe changes of blood pressures and urinary sodium and potassium excretion in response to acute oral saline loading among essential hypertensive patients in China.Methods Essential hypertensive patients from Beijing Jinzhan second community were included in this study.Salt-sensitivity was determined via the improved Sullivan’s acute oral saline loading

  1. Icon Duration and Development.

    Science.gov (United States)

    Gummerman, Kent; And Others

    In this study, developmental changes in duration of the icon (visual sensory store) were investigated with three converging tachistoscopic tasks. (1) Stimulus interuption detection (SID), a variation of the two-flash threshold method, was performed by 29 first- and 32 fifth-graders, and 32 undergraduates. Icon duration was estimated by stimulus…

  2. Glycemic index and glycemic load in relation to food and nutrient intake and metabolic risk factors in a Dutch population.

    Science.gov (United States)

    Du, Huaidong; van der A, Daphne L; van Bakel, Marit M E; van der Kallen, Carla J H; Blaak, Ellen E; van Greevenbroek, Marleen M J; Jansen, Eugène H J M; Nijpels, Giel; Stehouwer, Coen D A; Dekker, Jacqueline M; Feskens, Edith J M

    2008-03-01

    Previous studies on the glycemic index (GI) and glycemic load (GL) reported inconsistent findings on their association with metabolic risk factors. This may partly have been due to differences in underlying dietary patterns. We aimed to examine the association of GI and GL with food and nutrient intake and with metabolic risk factors including blood glucose, insulin, lipids, and high-sensitivity C-reactive protein (CRP). The study entailed cross-sectional analyses of data from 2 joint observational studies, the CoDAM Study and the Hoorn Study. In total, 974 subjects aged 42-87 y were included in the study. The mean (+/-SD) GI was 57 +/- 4 and the mean GL was 130 +/- 39. Dairy products, potatoes and other tubers, cereal products, and fruit were the main predictive food groups for GI. GL was closely correlated with intake of total carbohydrates (r(s) = 0.97), which explained >95% of the variation in GL. After adjustment for potential confounders, GI was significantly inversely associated with HDL cholesterol and positively associated with fasting insulin, the homeostasis model assessment index of insulin resistance, the ratio of total to HDL cholesterol, and CRP. No association was observed between GL and any of the metabolic risk factors, except for a borderline significant positive association with CRP. In this population, a low-GI diet, which is high in dairy and fruit but low in potatoes and cereals, is associated with improved insulin sensitivity and lipid metabolism and reduced chronic inflammation. GL is highly correlated with carbohydrate intake and is not clearly associated with the investigated metabolic risk factors.

  3. Stress intensity factors and crack opening areas for axial through cracks in hollow cylinders under internal pressure loading

    Energy Technology Data Exchange (ETDEWEB)

    Ehlers, R.

    1986-01-01

    For a linear-elastic cylinder with an axial through crack subject to internal pressure loading, stress intensity factors and crack opening areas were calculated by the finite element method. Wall thickness and crack length were varied for constant mean radius of the cylinder, thus varying the shell parameter lambda with 2.5 factors depend on lambda as well as on R/t and show considerable differences to solutions based on shallow shell theory even for very short cracks. The range of validity of these solutions is discussed. Starting from the observation that the energy release rate for a semi-infinite crack is finite, a simple interpolation formula is given that retains the proper asymptotic behaviour for very long and very short cracks. Crack opening areas are given and compared to an approximate analytical formula from the literature. Some general limitations of the validity of the present results, particularly the required minimum lengths of the cylinder, are discussed.

  4. Mechanical loading by fluid shear stress of myotube glycocalyx stimulates growth factor expression and nitric oxide production.

    Science.gov (United States)

    Juffer, Petra; Bakker, Astrid D; Klein-Nulend, Jenneke; Jaspers, Richard T

    2014-07-01

    Skeletal muscle fibers have the ability to increase their size in response to a mechanical overload. Finite element modeling data suggest that mechanically loaded muscles in vivo may experience not only tensile strain but also shear stress. However, whether shear stress affects biological pathways involved in muscle fiber size adaptation in response to mechanical loading is unknown. Therefore, our aim was twofold: (1) to determine whether shear stress affects growth factor expression and nitric oxide (NO) production by myotubes, and (2) to explore the mechanism by which shear stress may affect myotubes in vitro. C2C12 myotubes were subjected to a laminar pulsating fluid flow (PFF; mean shear stress 0.4, 0.7 or 1.4 Pa, 1 Hz) or subjected to uni-axial cyclic strain (CS; 15 % strain, 1 Hz) for 1 h. NO production during 1-h PFF or CS treatment was quantified using Griess reagent. The glycocalyx was degraded using hyaluronidase, and stretch-activated ion channels (SACs) were blocked using GdCl3. Gene expression was analyzed immediately after 1-h PFF (1.4 Pa, 1 Hz) and at 6 h post-PFF treatment. PFF increased IGF-I Ea, MGF, VEGF, IL-6, and COX-2 mRNA, but decreased myostatin mRNA expression. Shear stress enhanced NO production in a dose-dependent manner, while CS induced no quantifiable increase in NO production. Glycocalyx degradation and blocking of SACs ablated the shear stress-stimulated NO production. In conclusion, shear stress activates signaling pathways involved in muscle fiber size adaptation in myotubes, likely via membrane-bound mechanoreceptors. These results suggest that shear stress exerted on myofiber extracellular matrix plays an important role in mechanotransduction in muscle.

  5. Incidence, Duration, Persistence, and Factors Associated With High-risk Anal Human Papillomavirus Persistence Among HIV-negative Men Who Have Sex With Men: A Multinational Study

    Science.gov (United States)

    Nyitray, Alan G.; Carvalho da Silva, Roberto J.; Chang, Mihyun; Baggio, Maria Luiza; Ingles, Donna J.; Abrahamsen, Martha; Papenfuss, Mary; Lin, Hui-Yi; Salmerón, Jorge; Quiterio, Manuel; Lazcano-Ponce, Eduardo; Villa, Luisa L.; Giuliano, Anna R.

    2016-01-01

    Background. Given high rates of anal disease, we investigated the natural history of high-risk anal human papillomavirus (HPV) among a multinational group of men who have sex with men (MSM) aged 18–64 years. Methods. Anal specimens from human immunodeficiency virus–negative men from Brazil, Mexico, and the United States were genotyped. Over 2 years, 406 MSM provided evaluable specimens every 6 months for ≥2 visits. These men were stratified into men who have sex only with men (MSOM, n = 70) and men who have sex with women and men (MSWM, n = 336). Persistence was defined as ≥12 months’ type-specific duration and could begin with either a prevalent or incident infection. Prevalence ratios and 95% confidence intervals were calculated by Poisson regression. Results. Median follow-up time was 2.1 years. Retention was 82%. Annual cumulative incidence of 9-valent vaccine types was 19% and 8% among MSOM and MSWM, respectively (log-rank P = .02). Duration of anal HPV did not differ for MSOM and MSWM and was a median of 6.9 months for HPV-16 after combining men from the 2 groups. Among men with prevalent high-risk infection (n = 106), a total of 36.8%, retained the infection for at least 24 months. For those with prevalent HPV-16 (n = 27), 29.6% were persistent for at least 24 months. Persistence of high-risk HPV was associated with number of male anal sex partners and inversely associated with number of female sex partners. Conclusions. MSM with prevalent high-risk HPV infection should be considered at increased risk for nontransient infection. PMID:26962079

  6. 基于审查回归模型的失业持续期影响因素分析%Based on the Censored Regression Model to Analyze the Factors Affecting of Unemployment Duration

    Institute of Scientific and Technical Information of China (English)

    马莹; 裴晓敏

    2012-01-01

    针对我国失业人员的失业持续期问题,运用审查回归模型(Censored regression model)对影响失业持续时阍因素进行分析。结果显示:男性失业持续时问明显较女性短,教育对一个人再次就业有着明显的促进作用。个人进行人力资本的投资不但能够缩短失业持续时间,而且在当前我国就业形势严峻的局面下,个人受教育年限的多少对于一个人的成功就业也具有重要的意义。对于社会网络、家庭背景等影响劳动力就业的非市场因素,政府创造公平合理的就业竞争机制具有非常重要的作用。%In view of the unemployed duration of unemployment problem, using Censored regression model to analyze the factors affecting of unemployment duration. The results show that male unemployment duration was significantly shorter than that of women, education of a people once again have a significant role in promoting employment. Personal investment in human capital will not only shorten the duration of unemployment, but also in the current situation of China's employment situation is grim, the individual number of years of education for the employment of a person's success is also of great significance. For social networks, family background and other effects of non - market factors, labor employment, government employment and creating a fair competition mechanism has a very important role.

  7. From Sleep Duration to Childhood Obesity

    DEFF Research Database (Denmark)

    Börnhorst, Claudia; Hense, Sabrina; Ahrens, Wolfgang

    2012-01-01

    Sleep duration has been identified as risk factor for obesity already in children. Besides investigating the role of fat mass (FM), this study addressed the question whether endocrine mechanisms act as intermediates in the association between sleep duration and overweight/obesity. Within......-specific measure of sleep duration was derived to account for alteration in sleep duration during childhood/period of growth. Multivariate linear regression and quantile regression models confirmed an inverse relationship between sleep duration and measures of overweight/obesity. The estimate for the association...... of sleep duration and body mass index (BMI) was approximately halved after adjustment for FM, but remained significant. The strength of this association was also markedly attenuated when adjusting for insulin mainly for the upper BMI quantiles (Q80, β = −0.36 vs. β = −0.26; Q95, β = −0.87 vs. β = −0...

  8. Reliability assessment of offshore platforms exposed to wave-in-deck loading. Appendix F: Reliability analysis of offshore jacket structures with wave load on deck using the model correction factor method

    Energy Technology Data Exchange (ETDEWEB)

    Dalsgaard Soerensen, J. [Aalborg Univ., Aalborg (Denmark); Friis-Hansen, P. [Technical Univ. Denmark, Lyngby (Denmark); Bloch, A.; Svejgaard Nielsen, J. [Ramboell, Esbjerg (Denmark)

    2004-08-01

    Different simple stochastic models for failure related to pushover collapse are investigated. Next, a method is proposed to estimate the reliability of real offshore jacket structures. The method is based on the Model Correction Factor Method and can be used to very efficiently to estimate the reliability for total failure/collapse of jacket type platforms with wave in deck loads. A realistic example is evaluated and it is seen that it is possible to perform probabilistic reliability analysis for collapse of a jacket type platform using the model correction factor method. The total number of deterministic, complicated, non-linear (RONJA) analysis is typically as low as 10. Such reliability analyses are recommended to be used in practical applications, especially for cases with wave in deck load, where the traditional RSR analyses give poor measures of the structural reliability. (au)

  9. Evidence that gestation duration and lactation duration are coupled traits in primates.

    Science.gov (United States)

    Dubman, Evgenia; Collard, Mark; Mooers, Arne Ø

    2012-12-23

    Gestation duration and lactation duration are usually treated as independently evolving traits in primates, but the metabolic theory of ecology (MTE) suggests both durations should be determined by metabolic rate. We used phylogenetic generalized least-squares linear regression to test these different perspectives. We found that the allometries of the durations are divergent from each other and different from the scaling exponent predicted by the MTE (0.25). Gestation duration increases much more slowly (0.06 switch from gestation to lactation in relation to some as-yet-unidentified body-size-related factor.

  10. Regulation of the Dynamic Live Load Factor for Calculation of Bridge Structures on High-Speed Railway Mainlines

    Science.gov (United States)

    Dyachenko, Leonid K.; Benin, Andrey V.

    2017-06-01

    When the high-speed railway traffic is being organized, it becomes necessary to elaborate bridge design standards for high-speed railways (HSR). Methodology of studying the issues of HSR bridge design is based on the comprehensive analysis of domestic research as well as international experience in design, construction and operation of high-speed railways. Serious requirements are imposed on the HSR artificial structures, which raise a number of scientific tasks associated mainly with the issues of the dynamic interaction of the rolling stock and the bridge elements. To ensure safety of traffic and reliability of bridges during the whole period of operation one needs to resolve the dynamic problems of various types of high-speed trains moving along the structures. The article analyses dependences of the magnitude of inertial response on the external stress parameters and proposes a simplified method of determination of the dynamic live load factor caused by the passage of high-speed trains. The usefulness of the given research arises from the reduction of complexity of the complicated dynamic calculations needed to describe a high-speed train travelling along the artificial structures.

  11. Repair effect of diabetic ulcers with recombinant human epidermal growth factor loaded by sustained-release microspheres

    Institute of Scientific and Technical Information of China (English)

    DONG XiaoQing; XU Jun; WANG WeiCai; Luo Hao; LIANG XiaoFei; Zhang Lei; Wang HanJie; Wang PengHua; CHANG Jin

    2008-01-01

    In this study the w/o/w extraction-evaporation technique was adopted to prepare poly(lactic-co-glycolic acid) (PLGA) microspheres loading recombinant human epidermal growth factor (rhEGF). The micro-spheres were characterized for morphology by transmission electron microscopy (TEM) and particle size distribution. The release performances, the proliferation effects and therapeutic effects of rhEGF-Ioaded PLGA microspheres were all studied. The results showed that these spherical micro-spheres had a narrow size distribution and a high drug encapsulation efficiency (85.6%). RhEGF-ioaded microspheres enhanced the growth rate of fibroblasts and wound healing more efficiently than pure rhEGF. The number of the proliferating cell nuclear antigen (PCNA) in the epidermis layer with the mi-crosphere treatment was significantly larger than those of the control groups. Overall locally sustained delivery of rhEGF from biodegradable PLGA microspheres may serve as a novel therapeutic strategy for diabetic ulcer repair.

  12. In vitro characteristics of poly(lactic-co-glycolic acid) microspheres incorporating gelatin particles loading basic fibroblast growth factor

    Institute of Scientific and Technical Information of China (English)

    Shao-hong LI; Shao-xi CAI; Bing LIU; Kai-wang MA; Zhen-ping WANG; Xiao-kun LI

    2006-01-01

    Aim: To construct a sustained drug release system for basic fibroblast growth factor (bFGF). With this special system, bFGF can be used to repair an injured peripheral nerve, injured spinal cord, or as a carrier for other drugs that need to be released over a long time. Methods: Microsphere composite was prepared by encapsulating bFGF into gelatin particles with poly(lactic-co-glycolic acid) (PLGA) as its outer-coating. The encapsulation was conducted by a phase separation method. Results: The average diameter of the gelatin particle-PLGA microsphere composite was 5-18 μm, and bFGF-loading efficiency was up to 80.5%. The bFGF releasing experiment indicated that this new composite system could release bFGF continuously and protect bFGF from denaturation. Conclusion: A modified approach was successfully employed to develop a biodegradable system for sustained release of the drug of bFGF in vitro.

  13. Surgical wound healing using hemostatic gauze scaffold loaded with nanoparticles containing sustained-release granulocyte colony-stimulating factor

    Directory of Open Access Journals (Sweden)

    Yuan W

    2011-12-01

    Full Text Available Weien Yuan1,2, Zhenguo Liu11Department of Neurology, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 2School of Pharmacy, Shanghai Jiao Tong University, Shanghai, People's Republic of ChinaBackground: The therapeutic strategies for malignant melanoma are still cancer chemotherapy, radiotherapy, and tumor resection. However, these therapeutic strategies often lead to a reduced neutrophilic granulocyte count or loss of more blood after surgical tumor resection. In this study, we developed a formulation of hemostatic gauze impregnated with sustained-release granulocyte colony-stimulating factor (G-CSF with increasing of the neutrophilic granulocyte count in the blood following chemotherapy and decreasing blood loss after surgical tumor resection.Methods: We designed a formulation with both hemostatic properties and increased neutrophil content to be used in cancer chemotherapy, radiotherapy, and tumor resection, comprising a hemostatic gauze as a scaffold and (G-CSF-loaded dextran nanoparticles coated with polylactic-co-glycolic acid (PLGA solution fabricated by direct spray-painting onto the scaffold and then vacuum-dried at room temperature. The performance of this system was evaluated in vitro and in vivo.Results: Nearly zero-order release of G-CSF was recorded for 12–14 days, and the cumulative release of G-CSF retained over 90% of its bioactivity in a NFS-60 cell line proliferation assay when the scaffold was incubated in phosphate-buffered saline (pH 7.4 at 37°C. The in vivo hemostatic efficacy of this formulation was greater than that of native G-CSF, the scaffold directly spray-painted with G-CSF solution or PLGA organic solution as a coating, or when a blank scaffold was covered with the coating.Conclusion: Our results suggest that this formulation has both hemostatic properties and increased neutrophil activity.Keywords: hemostatic gauze scaffold, granulocyte colony-stimulating factor, bioactivity

  14. Season, Transport Duration and Trailer Compartment Effects on Blood Stress Indicators in Pigs: Relationship to Environmental, Behavioral and Other Physiological Factors, and Pork Quality Traits

    Directory of Open Access Journals (Sweden)

    Roberta Sommavilla

    2017-02-01

    Full Text Available The objective of this study was to assess the effects of the season, travel duration and trailer compartment location on blood creatine-kinase (CK, lactate and cortisol concentrations in 384 pigs and assess their relationships with trailer temperature, heart rate and gastrointestinal tract temperature (GTT, behavior, carcass damage scores and meat quality. Blood CK was greater in pigs transported in summer (p = 0.02, after 18 h transportation (p < 0.001 and in pigs located in C4, C5 and C10 (p = 0.002. In winter, the concentration of blood lactate was higher (p = 0.04 in pigs transported for 6 h in C5. Pigs located in C10 showed higher (p = 0.01 concentration of cortisol than those transported for 18h in C4 in summer. The highest correlations were between blood cortisol and GTT (r = 0.53; p < 0.001, and between blood CK and GTT (r = 0.41; p < 0.001, truck temperature (r = 0.42; p < 0.001, and pHu in the longissimus muscle (r = 0.41; p < 0.001. In conclusion, although increased blood cortisol and CK levels appear to indicate a physical stress condition in transported pigs, the weak to moderate correlations with environmental and other animal welfare indicators suggest that blood stress parameters can only be used as a complementary measurement in the assessment of the pigs’ response to transport stress.

  15. A methodology for multihazards load combinations of earthquake and heavy trucks for bridges.

    Science.gov (United States)

    Sun, Dezhang; Wang, Xu; Sun, Baitao

    2014-01-01

    Issues of load combinations of earthquakes and heavy trucks are important contents in multihazards bridge design. Current load resistance factor design (LRFD) specifications usually treat extreme hazards alone and have no probabilistic basis in extreme load combinations. Earthquake load and heavy truck load are considered as random processes with respective characteristics, and the maximum combined load is not the simple superimposition of their maximum loads. Traditional Ferry Borges-Castaneda model that considers load lasting duration and occurrence probability well describes random process converting to random variables and load combinations, but this model has strict constraint in time interval selection to obtain precise results. Turkstra's rule considers one load reaching its maximum value in bridge's service life combined with another load with its instantaneous value (or mean value), which looks more rational, but the results are generally unconservative. Therefore, a modified model is presented here considering both advantages of Ferry Borges-Castaneda's model and Turkstra's rule. The modified model is based on conditional probability, which can convert random process to random variables relatively easily and consider the nonmaximum factor in load combinations. Earthquake load and heavy truck load combinations are employed to illustrate the model. Finally, the results of a numerical simulation are used to verify the feasibility and rationality of the model.

  16. A Methodology for Multihazards Load Combinations of Earthquake and Heavy Trucks for Bridges

    Directory of Open Access Journals (Sweden)

    Dezhang Sun

    2014-01-01

    Full Text Available Issues of load combinations of earthquakes and heavy trucks are important contents in multihazards bridge design. Current load resistance factor design (LRFD specifications usually treat extreme hazards alone and have no probabilistic basis in extreme load combinations. Earthquake load and heavy truck load are considered as random processes with respective characteristics, and the maximum combined load is not the simple superimposition of their maximum loads. Traditional Ferry Borges-Castaneda model that considers load lasting duration and occurrence probability well describes random process converting to random variables and load combinations, but this model has strict constraint in time interval selection to obtain precise results. Turkstra’s rule considers one load reaching its maximum value in bridge’s service life combined with another load with its instantaneous value (or mean value, which looks more rational, but the results are generally unconservative. Therefore, a modified model is presented here considering both advantages of Ferry Borges-Castaneda's model and Turkstra’s rule. The modified model is based on conditional probability, which can convert random process to random variables relatively easily and consider the nonmaximum factor in load combinations. Earthquake load and heavy truck load combinations are employed to illustrate the model. Finally, the results of a numerical simulation are used to verify the feasibility and rationality of the model.

  17. Calculating load factors for the transatlantic airline market using supply and demand data: a note on the identification of gaps in the available airline statistics

    NARCIS (Netherlands)

    Devriendt, L.; Burghouwt, G.; Derudder, B.; de Wit, J.; Witlox, F.

    2009-01-01

    This paper takes a critical view of the verification of load factors for the direct transatlantic airline market by combining supply and demand-data. The supply-related data originate from the Official Airline Guide, a well-known data source that contains information on scheduled flights. The

  18. Daily spinal mechanical loading as a risk factor for acute non-specific low back pain: A case-control study using the 24-Hour Schedule

    NARCIS (Netherlands)

    E.W.P. Bakker (Eric); A.P. Verhagen (Arianne); C. Lucas (Cees); H.J.C.M.F. Koning (Hans); R.J. de Haan (Rob); B.W. Koes (Bart)

    2007-01-01

    textabstractA case-control study was conducted to assess the daily loading of the spine as a risk factor for acute non-specific low back pain (acute LBP). Acute LBP is a benign, self-limiting disease, with a recovery rate of 80-90% within 6 weeks irrespective of the treatment type. Unfortunately, re

  19. Daily spinal mechanical loading as a risk factor for acute non-specific low back pain: A case-control study using the 24-Hour Schedule

    NARCIS (Netherlands)

    E.W.P. Bakker (Eric); A.P. Verhagen (Arianne); C. Lucas (Cees); H.J.C.M.F. Koning (Hans); R.J. de Haan (Rob); B.W. Koes (Bart)

    2007-01-01

    textabstractA case-control study was conducted to assess the daily loading of the spine as a risk factor for acute non-specific low back pain (acute LBP). Acute LBP is a benign, self-limiting disease, with a recovery rate of 80-90% within 6 weeks irrespective of the treatment type. Unfortunately, re

  20. Calculating load factors for the transatlantic airline market using supply and demand data: a note on the identification of gaps in the available airline statistics

    NARCIS (Netherlands)

    Devriendt, L.; Burghouwt, G.; Derudder, B.; de Wit, J.; Witlox, F.

    2009-01-01

    This paper takes a critical view of the verification of load factors for the direct transatlantic airline market by combining supply and demand-data. The supply-related data originate from the Official Airline Guide, a well-known data source that contains information on scheduled flights. The demand

  1. Glycemic index and glycemic load in relation to food and nutrient intake and metabolic risk factors in a Dutch population 1-3

    NARCIS (Netherlands)

    Du, H.; A, van der D.L.; Bakel, van M.M.E.; Kallen, van der C.J.H.; Blaak, E.E.; Greevenbroek, van M.M.J.; Jansen, E.H.J.M.; Nijpels, Giel; Stehouwer, C.D.A.; Dekker, J.M.; Feskens, E.J.M.

    2008-01-01

    Background: Previous studies on the glycemic index (GI) and glycemic load (GL) reported inconsistent findings on their association with metabolic risk factors. This may partly have been due to differences in underlying dietary patterns. Objective: We aimed to examine the association of GI and GL wit

  2. Factors associated with short-term changes in HIV viral load and CD4+ cell count in antiretroviral-naive individuals

    DEFF Research Database (Denmark)

    Lundgren, Jens

    2014-01-01

    OBJECTIVES: Among antiretroviral therapy (ART)-naive individuals, viral load levels tend to increase and CD4(+) cell counts decline over time. We sought to explore the rate of change and influence of other factors associated with these markers of HIV progression. DESIGN: An observational cohort...

  3. Effects of diets differing in glycemic index and glycemic load on cardiovascular risk factors: review of randomized controlled-feeing trials

    Science.gov (United States)

    Despite a considerable amount of data available on the relationship between dietary glycemic index (GI) or load (GL) and cardiovascular disease (CVD) risk factors, in aggregate, the area remains unsettled. The aim of the present review was to summarize the effect of diets differing in GI/GL on CVD r...

  4. Pigment epithelial-derived factor gene loaded novel COOH-PEG-PLGA-COOH nanoparticles promoted tumor suppression by systemic administration.

    Science.gov (United States)

    Yu, Ting; Xu, Bei; He, Lili; Xia, Shan; Chen, Yan; Zeng, Jun; Liu, Yongmei; Li, Shuangzhi; Tan, Xiaoyue; Ren, Ke; Yao, Shaohua; Song, Xiangrong

    2016-01-01

    Anti-angiogenesis has been proposed as an effective therapeutic strategy for cancer treatment. Pigment epithelium-derived factor (PEDF) is one of the most powerful endogenous anti-angiogenic reagents discovered to date and PEDF gene therapy has been recognized as a promising treatment option for various tumors. There is an urgent need to develop a safe and valid vector for its systemic delivery. Herein, a novel gene delivery system based on the newly synthesized copolymer COOH-PEG-PLGA-COOH (CPPC) was developed in this study, which was probably capable of overcoming the disadvantages of viral vectors and cationic lipids/polymers-based nonviral carriers. PEDF gene loaded CPPC nanoparticles (D-NPs) were fabricated by a modified double-emulsion water-in-oil-in-water (W/O/W) solvent evaporation method. D-NPs with uniform spherical shape had relatively high drug loading (~1.6%), probably because the introduced carboxyl group in poly (D,L-lactide-co-glycolide) terminal enhanced the interaction of copolymer with the PEDF gene complexes. An excellent in vitro antitumor effect was found in both C26 and A549 cells treated by D-NPs, in which PEDF levels were dramatically elevated due to the successful transfection of PEDF gene. D-NPs also showed a strong inhibitory effect on proliferation of human umbilical vein endothelial cells in vitro and inhibited the tumor-induced angiogenesis in vivo by an alginate-encapsulated tumor cell assay. Further in vivo antitumor investigation, carried out in a C26 subcutaneous tumor model by intravenous injection, demonstrated that D-NPs could achieve a significant antitumor activity with sharply reduced microvessel density and significantly promoted tumor cell apoptosis. Additionally, the in vitro hemolysis analysis and in vivo serological and biochemical analysis revealed that D-NPs had no obvious toxicity. All the data indicated that the novel CPPC nanoparticles were ideal vectors for the systemic delivery of PEDF gene and might be widely

  5. Effect of Exposure to Various Durations of Light on Serum Insulin-Like Growth Factor-I in Prepubertal Holstein Heifers

    Directory of Open Access Journals (Sweden)

    L. J. Spicer

    2007-01-01

    Full Text Available Our objective was to determine if prolonged exposure to various durations of light (i.e., photoperiod would affect serum IGF-I concentrations in heifers. Thus, 16 Holstein heifers, 2 to 4 mo of age, were exposed during a 5-wk pretreatment period to 12 h of cool-white fluorescent light (L at an intensity of 1200 lux and 12 h of dark (D. At 5 wk, photoperiods were adjusted to 24 L: 0 D (24 L, 20 L: 4 d (20 L, 16 L: 8 D (16 L or 8 L: 16 D (8 L per 24 h (n=4 heifers per photoperiod treatment. Blood was sampled at 5 wk and monthly for 4 mo. During each sampling period, blood was collected at 16-h intervals for 48 h and serum IGF-I was determined by RIA. Photoperiod treatment, month of experiment and their interactions affected serum IGF-I concentrations. Averaged over months, concentrations of serum IGF-I was greatest in heifers on 16 L; heifers on 20 L had IGF-I concentrations similar to 8 L, 16 L and 24 L and heifers on 24 L had concentrations similar to that of heifers on 8 L. Heifers in all treatment groups exhibited an increase in serum IGF-I concentration during the 4 mo of treatment. Heifers on 16 L and 20 L exhibited the greatest difference in serum IGF-I concentrations compared with 8L heifers after 3 mo of treatment. In conclusion, 16 L increases concentrations of serum IGF-I above that seen for heifers treated with

  6. Analysis of Impact Factors on Wind Turbine Fatigue Loads (Ⅲ)%风电机组疲劳载荷影响因素分析(三)

    Institute of Scientific and Technical Information of China (English)

    许移庆

    2013-01-01

    Wind turbine design is mainly dominated by fatigue loads and extreme loads. Fatigue loads are especially important for some components design because of uncertainty and instability of wind turbine operation environment. Tere are many impact factors for wind turbine fatigue loads. Tis paper mostly compared two impact factors, namely diferent design operation wind speed range and diferent design turbulence intensity classes, and analyzed their efect extent for fatigue loads.%风电机组设计主要由疲劳载荷和极限载荷决定,而风电机组运行环境的不确定性和不稳定性使得疲劳载荷对一些部件的设计尤为重要。影响疲劳载荷的因素很多,本文主要从不同设计运行风速范围和不同设计湍流强度等级两个方面进行比较,分析了两者各自对疲劳载荷影响的程度。

  7. 风电机组疲劳载荷影响因素分析(二)%Analysis of Impact Factors on Wind Turbine Fatigue Loads (Ⅱ)

    Institute of Scientific and Technical Information of China (English)

    许移庆

    2013-01-01

    Wind turbine design is mainly dominated by fatigue loads and extreme loads. Fatigue loads are especially important for some components design because of uncertainty and instability of wind turbine operation environment. Tere are many impact factors for wind turbine fatigue loads. Tis paper mostly compared two impact factors, namely diferent design operation wind speed range and diferent design turbulence intensity classes, and analyzed their efect extent for fatigue loads.%风电机组设计主要由疲劳载荷和极限载荷决定,而风电机组运行环境的不确定性和不稳定性使得疲劳载荷对一些部件的设计尤为重要。影响疲劳载荷的因素很多,本文主要从不同设计运行风速范围和不同设计湍流强度等级两个方面进行比较,分析了两者各自对疲劳载荷影响的程度。

  8. Duration of breastfeeding and its relevant influencing factors in urban and rural areas of Chengdu%成都地区城乡母乳喂养持续时间及其影响因素研究

    Institute of Scientific and Technical Information of China (English)

    黄璐娇; 曾果; 李鸣; 冉隆蓉; 陈科; 庞学红; 余利

    2012-01-01

    目的 研究成都地区母乳喂养持续时间及其影响因素.方法 采用分层整群随机抽样法选取成都地区城乡1178名6 ~ 24月龄婴幼儿作为研究对象,通过问卷调查收集婴幼儿及家庭基本情况和母乳喂养相关信息,运用Kaplan-Meier法和Cox比例风险模型分析母乳喂养持续时间及其影响因素.结果 调查对象母乳喂养持续时间(P50)分别为城市6.0个月(P25~p75:3~8.5个月)和农村8.0个月(P25~P75:5 ~11个月),城乡差异有显著性(P<0.05);婴幼儿饮食月消费与母乳喂养持续时间呈负相关(城乡RR值分别为0.163和0.312),母亲产假与母乳喂养持续时间呈正相关(城乡RR值分别为1.508和2.191).结论 成都地区母乳喂养时间普遍不足,需采取针对性的干预措施给予改善.%Objective To investigate the status and relevant factors influencing the duration of breastfeeding in urban and rural areas of Chengdu, China. Methods 1178 infants and young children aged 6-24 months were selected by stratified cluster random sampling. Breastfeeding information for subjects was obtained by interviewing mothers with a questionnaire. Kaplan-Meier method and Cox proportional hazard model were used to identify the factors associated with the termination of breastfeeding. Results The median of the duration for breastfeeding was 6. 0 months in the urban group and 8. 0 months in the rural group ( P < 0. 05 ) . This study showed that the cost of food consumed by baby was negatively correlated with breastfeeding duration, but the maternity leave was positively correlated with breastfeeding duration. Conclusion Breastfeeding duration for children in Chengdu was insufficient. Intervention program should be implemented to improve breastfeeding status.

  9. Glycemic index and glycemic load are associated with some cardiovascular risk factors among the PREMIER study participants

    Directory of Open Access Journals (Sweden)

    Pao-Hwa Lin

    2012-06-01

    Full Text Available Background: The clinical significance of glycemic index (GI and glycemic load (GL is inconclusive. Objective : This study was conducted to examine the association of GI and GL with clinical cardiovascular disease (CVD risk factors including body weight, blood pressure (BP, serum lipids, fasting glucose, insulin and homocysteine over time among the PREMIER participants. Design: PREMIER was an 18-month randomized lifestyle intervention trial, conducted from 2000 to 2002, designed to help participants reduce BP by following the Dietary Approaches to Stop Hypertension (DASH dietary pattern, losing weight, reducing sodium and increasing physical activity. GI and GL were estimated from 24 h diet recall data at baseline, 6 and 18 months after intervention. PROC MIXED model was used to examine the association of changes in GI or GL with changes in CVD risk factors. Results: A total of 756 randomized participants, 62% females and 34% African Americans and who averaged 50.0±0.3 years old and 95.3±0.7 kg, were included in this report. Neither GI nor GL changes was associated with changes in any risk factors at 6 months. At 18 months, however, the GI change was significantly and positively associated with total cholesterol (TC change only (p<0.05, β = 23.80±12.11 mg/dL or 0.62±0.31 mmol/L with a significant age interaction. The GL change was significantly associated with TC (p=0.02, β = 0.28±0.15 mg/dL or 0.01±0.00 mmol/L positively and with low density lipoprotein cholesterol (LDL-C changes negatively (p=0.03, β = − 0.01±0.00 mg/dL or −0.00±0.00 mmol/L, and significant age interactions were observed for both. Conclusion: GI and GL was associated with TC and LDL-C after controlling for energy, fat and fiber intake and other potential confounders and the associations were modified by age. Further investigation into this relationship is important because of its potential clinical impact.

  10. Prognostic factors for duration of sick leave in patients sick listed with acute low back pain: A systematic review of the literature

    NARCIS (Netherlands)

    Steenstra, I.A.; Verbeek, J.H.; Heymans, M.W.; Bongers, P.M.

    2005-01-01

    Background: The percentages of patients with acute low back pain (LBP) that go on to a chronic state varies between studies from 2% to 34%. In some of these cases low back pain leads to great costs. Aims: To evaluate the evidence for prognostic factors for return to work among workers sick listed

  11. Factors affecting the potential of direct load control for non-generating utilities. Final report. [Distribution and wholesale power supply interaction

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-04-01

    Several alternatives are available for achieving load management, including direct or voluntary control of customer loads, customer or utility energy storage systems for diurnal load shifting, and expanded interconnection and operation of electric power systems. All of these alternatives are available to the fully integrated (generating, transmitting and distributing) electric utility and the analysis of their effects encompasses the power supply and delivery system. However, the costs and benefits of the alternatives to the fully integrated electric utility are perhaps not so obvious. Therefore, by considering a non-generating utility, this analysis focuses upon the distribution system and wholesale power supply interaction as a step toward an analysis including the power supply and delivery system. This report develops an analysis procedure and discusses some of the relevant factors to be consdered in the application of direct load control for a non-generating utility system. The analysis concentrates on the distribution system only to determine the effect of rates and payback as a result of direct load control. Thus, the study is responsive to the specific needs of the non-generating utility. This analysis of direct load control encompasses the determination of those loads amenable to control, the selection of a suitable one-way communications system to rend control and the estimation of expected benefits and costs. The complementary functions to the application of direct load control such as automatic meter reading via the addition of a bi-directional communications system and voltage control are not included in the analysis but are detailed for future consideration.

  12. 近40 a甘南高原日照时数变化趋势及影响因子%Variation Trend Analysis on Sunshine Duration and Its Impact Factors in Gannan Plateau in Recent 40 Years

    Institute of Scientific and Technical Information of China (English)

    王建兵; 敖泽建; 陈洋

    2014-01-01

    Gannan Plateau located in the southwest of Gansu Province and in the northeast border region of the Tibetan Plateau,which is an important water conserving and supplying area in the upriver regions of Yellow River.It plays an important role in the mainte-nance of water resource and eco-environmental security of the Yellow River basin.Due to the impact of climate change and the man activities,the ecology and environment of Gannan Plateau had obviously changed.So,this paper carried out the research about the change characteristic of sunshine duration in Gannan Plateau in order to provide the reference for the study of climate change in the Ti-betan Plateau. Based on the meteorological data of sunshine duration at 8 weather stations in Gannan Plateau from 1971 to 2000,the temporal and spatial variations of sunshine duration and its impact factors were studied by using trend analysis,Mann-Kendall test and principal component analysis,etc.The results show that the spatial distribution of annual average sunshine duration in the Gannan Plateau was far from uniformity.The sunshine duration in the western part of the Gannan Plateau was great more than that in the eastern part.The monthly variation of sunshine duration in the Gannan Plateau showed 3 peaks and 3 troughs.The sunshine duration in the 1970s and 1980s was least,increased obviously in the 1990s and the sunshine duration in the western of the Gannan Plateau showed a decreasing tendency in the 2000s,while in the eastern it showed an contrary increasing tendency.Furthermore,the mutation analysis shows that there were 3 types of sunshine duration variety in the Gannan Plateau.The first type was the detected mutation,the sunshine duration was still increasing,such as Zhuoni and Diebu counties,the second was the detected mutation,but the sunshine duration showed a de-creasing trend,such as Xiahe,Maqu and Zhouqu,and the third was no mutation,such as Hezuo,Luqu and Lintan.The variety of sunshine duration was closely

  13. Time-resolved spark-source mass spectroscopy: the effect of spark duration on relative sensitivity factors, ion intensity and precision of analysis

    Energy Technology Data Exchange (ETDEWEB)

    Franklin, James Curry [Univ. of Tennessee, Knoxville, TN (United States)

    1971-01-29

    A radio-frequency, high-voltage spark ion source in conjunction with a double-focusing mass spectrometer has been used to measure the relative sensitivity factors for several elements in matrices of tin, iron, beryllium oxide, uranium, and steels. The sensitivity factors were examined for concentration and matrix effects. No significant variations were found for the concentration ranges studied, but there were very large sensitivity variations with changes in the matrix type. In order to accomplish this study, circuits were designed and installed to synchronize the ion-beam chopping circuits with the radio-frequency spark pulses so that time-resolved spectra were obtained at different periods in the spark pulse.

  14. Pigment epithelial-derived factor gene loaded novel COOH-PEG-PLGA-COOH nanoparticles promoted tumor suppression by systemic administration

    Directory of Open Access Journals (Sweden)

    Yu T

    2016-02-01

    Full Text Available Ting Yu,1,* Bei Xu,1,* Lili He,2 Shan Xia,3 Yan Chen,1 Jun Zeng,1 Yongmei Liu,1 Shuangzhi Li,1 Xiaoyue Tan,4 Ke Ren,1 Shaohua Yao,1 Xiangrong Song1 1State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, 2College of Chemistry and Environment Protection Engineering, Southwest University for Nationalities, 3Central Laboratory, Science Education Department, Chengdu Normal University, Chengdu, Sichuan, 4Department of Pathology/Collaborative Innovation Center of Biotherapy, Medical School of Nankai University, Tianjin, People’s Republic of China *These authors contributed equally to this work Abstract: Anti-angiogenesis has been proposed as an effective therapeutic strategy for cancer treatment. Pigment epithelium-derived factor (PEDF is one of the most powerful endogenous anti-angiogenic reagents discovered to date and PEDF gene therapy has been recognized as a promising treatment option for various tumors. There is an urgent need to develop a safe and valid vector for its systemic delivery. Herein, a novel gene delivery system based on the newly synthesized copolymer COOH-PEG-PLGA-COOH (CPPC was developed in this study, which was probably capable of overcoming the disadvantages of viral vectors and cationic lipids/polymers-based nonviral carriers. PEDF gene loaded CPPC nanoparticles (D-NPs were fabricated by a modified double-emulsion water-in-oil-in-water (W/O/W solvent evaporation method. D-NPs with uniform spherical shape had relatively high drug loading (~1.6%, probably because the introduced carboxyl group in poly (D,L-lactide-co-glycolide terminal enhanced the interaction of copolymer with the PEDF gene complexes. An excellent in vitro antitumor effect was found in both C26 and A549 cells treated by D-NPs, in which PEDF levels were dramatically elevated due to the successful transfection of PEDF gene. D-NPs also showed a strong inhibitory effect on

  15. [Prevalence of factors associated with the duration of exclusive breastfeeding during the first 6 months of life in the INMA birth cohort in Gipuzkoa].

    Science.gov (United States)

    Oribe, Madalen; Lertxundi, Aitana; Basterrechea, Mikel; Begiristain, Haizea; Santa Marina, Loreto; Villar, María; Dorronsoro, Miren; Amiano, Pilar; Ibarluzea, Jesús

    2015-01-01

    To estimate the prevalence of exclusive breastfeeding (EB) during the first 6 months of life in the Gipuzkoa birth cohort, identify the reasons for abandonment of EB, and establish the associated factors. The study population consisted of 638 pregnant women from the INMA-Gipuzkoa (Infancia y Medio Ambiente, www.proyectoinma.org) birth cohort, who were followed up from the third trimester of pregnancy until the child was aged 14 months. To determine the factors related to abandonment of EB, logistic regression models were used in two different stages (4 months or early stage and 6 months or late stage). The prevalence of EB within the Gipuzkoa cohort was 84.8% after hospital discharge, 53.7% at 4 months of life and 15.4% at 6 months of life. The reasons given by the mothers for early EB cessation were: breastfeeding problems, low weight gain and hypogalactia. Other factors influencing the early phase were the intention to provide EB, parity, area of residence and social class. Abandonment in the late stage was influenced by the length of maternity leave. From a public health perspective, the results of this study could help health professionals to develop strategies to support breastfeeding mothers, taking into account the main reasons for early and late abandonment. Copyright © 2014 SESPAS. Published by Elsevier Espana. All rights reserved.

  16. Duration Calculus: Logical Foundations

    DEFF Research Database (Denmark)

    Hansen, Michael Reichhardt; Chaochen, Zhou

    1997-01-01

    The Duration Calculus (abbreviated DC) represents a logical approach to formal design of real-time systems, where real numbers are used to model time and Boolean valued functions over time are used to model states and events of real-time systems. Since it introduction, DC has been applied to many...

  17. The Duration of Development

    NARCIS (Netherlands)

    J. Tinbergen (Jan)

    1995-01-01

    textabstractThe author considers the problem of the duration of development and its consequences for development assistance, in the developing as well as developed countries. Emphasis is given to the influence of development aid and it is argued that the time dimension has important policy implicati

  18. A numerical analysis of stress intensity factors for cracks emanating from an elliptical hole in a rectangular plate under biaxial loads

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Concerns with stress intensity factors for cracks emanating from an elliptical hole in a rectangular plate under biaxial loads by means of a boundary element method which consists of non-singular displacement discontinuity element presented by Crouch and Starfied[6] and crack-tip displacement discontinuity elements proposed by the author. In the boundary elenent implementation the left or the right crack-tip displacement discontinuity element is placed locally at the corresponding left or right crack tip on top of the constant displacement discontinuity elements that cover the entire crack surface and other boundaries. The present numerical results further illustrate that the present numerical approach is very effective and accurate for calculating stress intensity factors of complex cracks in a finite plate and can reveal the effect of the biaxial load and the cracked body geometry on stress intensity factors.

  19. Factors related to external loads in buried pipelines; Consideracoes quanto as variaveis relacionadas ao carregamento externo em dutos enterrados

    Energy Technology Data Exchange (ETDEWEB)

    Provenzano, Carlos E.C.; Silva, Breno S.; Fernandes, Lincoln F.; Santos Junior, Sergio J.F. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Louzada, Carlos H.C.M.

    2005-07-01

    Work of heavy equipment or vehicles above existent right-of-ways, may cause undesired external overload at buried pipelines in operation. The effect of these loads shall be analyzed considering the deflections and stresses on the pipelines. The major variables, nominal diameter, thickness, material, soil parameters, operation pressure and external loads shall be related and verified according to the limits from original project. Cases when the external loads cause higher efforts, the traffic over the pipelines shall be restricted in order to avoid damages. In other cases, it may be adapted to any technical alternatives to modify the parameters in such a way to make possible work above the right-of-way, such as increase the machine support area, increase backfill covering, a reduction in the internal operation pressure in a short time, etc. This work presents the study on the parameters used to establish the maximum allowable external loads over buried pipelines in operation. (author)

  20. A functional insulin-like growth factor receptor is not necessary for load-induced skeletal muscle hypertrophy

    National Research Council Canada - National Science Library

    Espen E. Spangenburg; Derek Le Roith; Chris W. Ward; Sue C. Bodine

    2008-01-01

    ...-I), which is thought to be a critical step in the induction of muscle hypertrophy. To determine the role of the IGF-I receptor in load-induced skeletal muscle hypertrophy, we utilized a transgenic mouse model (MKR...

  1. Enhanced antidepressant-like effects of the macromolecule trefoil factor 3 by loading into negatively charged liposomes

    Directory of Open Access Journals (Sweden)

    Qin J

    2014-11-01

    Full Text Available Jing Qin,1 Xu Yang,1–3 Jia Mi,4 Jianxin Wang,1 Jia Hou,1,2 Teng Shen,1 Yongji Li,2 Bin Wang,4 Xuri Li,4 Weili Zhu5 1Department of Pharmaceutics, School of Pharmacy, Fudan University, Key Laboratory of Smart Drug Delivery, Ministry of Education, Shanghai, 2Department of Pharmaceutics, School of Pharmacy, Heilongjiang University of Chinese Medicine, Harbin, 3Department of Pharmacy, The Fifth People’s Hospital of Shanghai, Fudan University, Shanghai, 4Binzhou Medical University, Yantai, 5National Institute on Drug Dependence, Peking University, Beijing, People’s Republic of China Abstract: Immunocytes, mainly neutrophils and monocytes, exhibit an intrinsic homing property, enabling them to migrate to sites of injury and inflammation. They can thus act as Trojan horses carrying concealed drug cargoes while migrating across impermeable barriers to sites of disease, especially the blood–brain barrier (BBB. In this study, to target circulating phagocytic cells, we formulated negatively charged nanosize liposomes and loaded trefoil factor 3 (TFF3 into liposomes by the pH-gradient method. According to the optimized formulation (5:1.5 of lipid to cholesterol, 10:1 of lipid to drug, 10 mg/mL of lipid concentration, and 10 mmol/L of phosphate-buffered saline, 44.47% entrapment efficiency was obtained for TFF3 liposomes with 129.6 nm particle size and –36.6 mV zeta potential. Compared with neutrally charged liposomes, the negatively charged liposomes showed a strong binding capacity with monocytes and were effectively carried by monocytes to cross the BBB in vitro. Furthermore, enhanced antidepressant-like effects were found in the tail-suspension and forced-swim tests in mice, as measured by decreased immobility time, as well as increased swimming time and reduced immobility in rats. These results suggested that negatively charged liposomes could improve the behavioral responses of TFF3, and our study opens up a new way for the development of

  2. Effect of low-glycemic load diet on changes in cardiovascular risk factors in poorly controlled diabetic patients

    Directory of Open Access Journals (Sweden)

    Ahmad Afaghi

    2012-01-01

    Full Text Available Background: One dietary strategy aimed at improving both diabetes control and control of cardiovascular risk factors is the use of low glycemic index diets. These diets have been reported to be beneficial in controlling diabetes, and also increase high density lipoprotein cholesterol (HDL-C, lower serum triglyceride, and reduce glycated protein. Aim: Therefore, we aimed to investigate the effect of a low glycemic index-low glycemic load (GL = 67-77 diet on lipids and blood glucose of poorly controlled diabetic patients. Materials and Methods: In an intervention study, 100 poorly controlled diabetic patients (age 52.8 ± 4.5 years who were taking insulin or on oral medication underwent administration of low GL diet (GL = 67-77; energy = 1800-2200 kcal, total fat = 36%, fat derived from olive oil and nuts 15%, carbohydrate = 41%, protein = 22% for 10 weeks. Patients were recommended to follow their regular lifestyle. Total cholesterol, low density lipoprotein (LDL, HDL, triglyceride, glycated hemoglobin (HbA1c, weight, and body mass index (BMI were measured before and 10 weeks after the intervention. Results: Before intervention, initial blood cholesterol and triglyceride concentrations were 205.9 ± 21.6 and 181.5 ± 22.2, respectively, and were reduced to 182.6 ± 18.2 and 161.6 ± 16.7, respectively, after 10 weeks intervention (P < 0.001. LDL reduced and HDL increased significantly. The HbA1c percentage reduced by 12% (from 8.85 ± 0.22% to 7.81 ± 0.27% (P < 0.001, and also their weight significantly reduced from 74.0 ± 5 kg to 70.7 ± 4.6 kg (P < 0.001. Conclusion: This study demonstrated that low GL diet having lower carbohydrate amount and higher fat content is an appropriate strategy in blood lipid and glucose response control of poorly controlled diabetic patients.

  3. Simulated Obstructive Sleep Apnea Increases P-Wave Duration and P-Wave Dispersion

    Science.gov (United States)

    Wons, Annette M.; Rossi, Valentina; Bratton, Daniel J.; Schlatzer, Christian; Schwarz, Esther I.; Camen, Giovanni; Kohler, Malcolm

    2016-01-01

    Background A high P-wave duration and dispersion (Pd) have been reported to be a prognostic factor for the occurrence of paroxysmal atrial fibrillation (PAF), a condition linked to obstructive sleep apnea (OSA). We tested the hypothesis of whether a short-term increase of P-wave duration and Pd can be induced by respiratory manoeuvres simulating OSA in healthy subjects and in patients with PAF. Methods 12-lead-electrocardiography (ECG) was recorded continuously in 24 healthy subjects and 33 patients with PAF, while simulating obstructive apnea (Mueller manoeuvre, MM), obstructive hypopnea (inspiration through a threshold load, ITH), central apnea (AP), and during normal breathing (BL) in randomized order. The P-wave duration and Pd was calculated by using dedicated software for ECG-analysis. Results P-wave duration and Pd significantly increased during MM and ITH compared to BL in all subjects (+13.1ms and +13.8ms during MM; +11.7ms and +12.9ms during ITH; p<0.001 for all comparisons). In MM, the increase was larger in healthy subjects when compared to patients with PAF (p<0.05). Conclusion Intrathoracic pressure swings through simulated obstructive sleep apnea increase P-wave duration and Pd in healthy subjects and in patients with PAF. Our findings imply that intrathoracic pressure swings prolong the intra-atrial and inter-atrial conduction time and therefore may represent an independent trigger factor for the development for PAF. PMID:27071039

  4. Protamine-containing insulin but not analog insulin and duration of insulin use are risk factors for the production of insulin autoantibodies in insulin-treated patients with diabetes mellitus.

    Science.gov (United States)

    Nishimura, Hidenao; Iizuka, Katsumi; Takeda, Jun

    2014-01-01

    Insulin autoantibodies can be produced by insulin injections but rarely cause severe side effects such as glucose instability and insulin allergy. We study the characteristics of insulin autoantibody-positive diabetic patients with a medical history of insulin therapy using single and multiple (adjusted for age, sex, type of diabetes) logistic regression analyses. Associations between insulin autoantibodies and age, sex, type of diabetes, HbA1c, and serum creatinine were not significant, but the association between insulin autoantibodies and duration of insulin use was significant. Unadjusted and adjusted odds ratios were 1.08 (1.02-1.14) and 1.07 (1.01-1.14), respectively. Unadjusted and adjusted odds ratios for protamine-containing insulin were 3.08 (1.49-6.34) and 4.27 (1.90-9.58), respectively. The adjusted odds ratios for premixed biphasic insulin and intermediate-acting insulin were 2.21 (1.03-4.73) and 2.35 (1.01-5.49), respectively. Associations between insulin autoantibodies and any insulin analog were not significant. These results suggest that protamine-containing insulin and duration of insulin use are risk factors for the production of insulin autoantibodies. If patients with poorly controlled diabetes have a history of protamine-containing insulin therapy over a long time, the appearance of insulin autoantibodies should be monitored.

  5. Thermal loading as a causal factor in exceeding the 0.1 PPM laboratory fume hood control level.

    Science.gov (United States)

    Chessin, Saul J; Johnston, James D

    2002-07-01

    Tracer gas testing per ANSI/ASHRAE 110-1995 Method of Testing Performance of Laboratory Fume Hoods was used to investigate the role of thermal loading in exceeding laboratory fume hood control levels. Three types of typical laboratory burners (blast, Meeker, and economy) were used to provide a thermal challenge. Heat outputs of between 0 and 61,610 Btu/hr were based on fuel heat capacity (for liquid propane gas) and fuel gas flow rates. Breathing zone concentrations were measured with a MIRAN 1B2 infrared gas analyzer. Also, for each test, the difference between the room and duct temperatures (delta temperature) was measured. Results indicated a linear relationship between heat loads and tracer gas breathing zone concentrations for both Btu/hr and delta temperature. Control levels of 0.1 ppm were exceeded at less than 12,000 Btu/hr. Also, control levels were exceeded at a lower heat load when the tracer gas generation rate was increased. These results indicate that thermal loads in laboratory fume hoods increase the risk of exceeding laboratory fume hood control levels. Some compensatory measures relative to hood configuration and flow rates are recommended for laboratory operations involving heat sources.

  6. Mechanical loading by fluid shear stress of myotube glycocalyx stimulates growth factor expression and nitric oxide production

    NARCIS (Netherlands)

    Juffer, P.; Bakker, A.D.; Klein-Nulend, J.; Jaspers, R.T.

    2014-01-01

    Skeletal muscle fibers have the ability to increase their size in response to a mechanical overload. Finite element modeling data suggest that mechanically loaded muscles in vivo may experience not only tensile strain but also shear stress. However, whether shear stress affects biological pathways i

  7. Long duration flights management

    Science.gov (United States)

    Sosa-Sesma, Sergio; Letrenne, Gérard; Spel, Martin; Charbonnier, Jean-Marc

    Long duration flights (LDF) require a special management to take the best decisions in terms of ballast consumption and instant of separation. As a contrast to short duration flights, where meteorological conditions are relatively well known, for LDF we need to include the meteorological model accuracy in trajectory simulations. Dispersions on the fields of model (wind, temperature and IR fluxes) could make the mission incompatible with safety rules, authorized zones and others flight requirements. Last CNES developments for LDF act on three main axes: 1. Although ECMWF-NCEP forecast allows generating simulations from a 4D point (altitude, latitude, longitude and UT time), result is not statistical, it is determinist. To take into account model dispersion a meteorological NCEP data base was analyzed. A comparison between Analysis (AN) and Forecast (FC) for the same time frame had been done. Result obtained from this work allows implementing wind and temperature dispersions on balloon flight simulator. 2. For IR fluxes, NCEP does not provide ascending IR fluxes in AN mode but only in FC mode. To obtain the IR fluxes for each time frame, satellite images are used. A comparison between FC and satellites measurements had been done. Results obtained from this work allow implementing flux dispersions on balloon flight simulator. 3. An improved cartography containing a vast data base had been included in balloon flight simulator. Mixing these three points with balloon flight dynamics we have obtained two new tools for observing balloon evolution and risk, one of them is called ASTERISK (Statistic Tool for Evaluation of Risk) for calculations and the other one is called OBERISK (Observing Balloon Evolution and Risk) for visualization. Depending on the balloon type (super pressure, zero pressure or MIR) relevant information for the flight manager is different. The goal is to take the best decision according to the global situation to obtain the largest flight duration with

  8. Evaluating Factors that Affect Construction Project Duration

    Science.gov (United States)

    1992-09-01

    Robinson Report on Artificial Intelligence, Vol 5, No. 3 (March 1989). Arditi , David, "Diffusion of Network Planning in Construction," Journal of the...Construction Division, Vol 109, No. CO1 (American Society of Civil Engineers [ASCE], March 1983). Arditi , David, et al., "Line of Balance Scheduling in

  9. Load-Dependent Emission Factors and Chemical Characteristics of IVOCs from a Medium-Duty Diesel Engine.

    Science.gov (United States)

    Cross, Eben S; Sappok, Alexander G; Wong, Victor W; Kroll, Jesse H

    2015-11-17

    A detailed understanding of the climate and air quality impacts of mobile-source emissions requires the characterization of intermediate-volatility organic compounds (IVOCs), relatively-low-vapor-pressure gas-phase species that may generate secondary organic aerosol with high yields. Due to challenges associated with IVOC detection and quantification, IVOC emissions remain poorly understood at present. Here, we describe measurements of the magnitude and composition of IVOC emissions from a medium-duty diesel engine. Measurements are made on an engine dynamometer and utilize a new mass-spectrometric instrument to characterize the load dependence of the emissions in near-real-time. Results from steady-state engine operation indicate that IVOC emissions are highly dependent on engine power, with highest emissions at engine idle and low-load operation (≤25% maximum rated power) with a chemical composition dominated by saturated hydrocarbon species. Results suggest that unburned fuel components are the dominant IVOCs emitted at low loads. As engine load increases, IVOC emissions decline rapidly and become increasingly characterized by unsaturated hydrocarbons and oxygenated organics, newly formed from incomplete combustion processes at elevated engine temperatures and pressures. Engine transients, including a cold-start ignition and engine acceleration, show IVOC emission profiles that are different in amount or composition compared to steady-state combustion, underscoring the utility of characterizing IVOC emissions with high time resolution across realistic engine operating conditions. We find possible evidence for IVOC losses on unheated dilution and sampling surfaces, which need to be carefully accounted for in IVOC emission studies.

  10. Factors of risk of physical load and diagnosis of osteomuscular changes in workers of coalmines in Ubaté valley

    Directory of Open Access Journals (Sweden)

    Édgar Humberto Velandia Bacca

    2004-06-01

    Full Text Available This study was done in Valle the Ubate minerarea and its main objective was to determine thephysical load and forced posture risk factorsrelated with muscle skeletal alterations inminers.Methodology: Cross sectional study. 49 minerswere evaluated according to the coal mine tunneland the work place. For the evaluation of thehealth conditions of the workers, two instrumentswere design: one for the labor and clinic historyand the other one to register the muscle skeletal conditions. These instruments were applied by aphysiatrist. To evaluate the physical load and theposture OWAS (Ovako Working Posture AnalysisSystem method was used.Results: Postural alterations related with thevertebral axis and the shoulder were found,specially in those workers of mines with horizontaltunnels. Knee laxity ligament was foundspecially in those workers of mines with nonhorizontal tunnels.Conclusion: The muscle skeletal disorders foundin the spine and shoulder seem to be due to the permanent posture in flexion of the cervical andlumbar spine, that can be add to the forcedmovements in rotation and the manipulation ofheavy loads between 10 and 20 Kg. It isnecessary to continue studying, from theepidemiological and clinical point of view, Thealterations that miners presents on their needs,because these alterations have been report inothers studies too.

  11. 影响人工骨载药微球发挥作用的因素%Factors affecting the function of drug-loaded microspheres in artificial bone

    Institute of Scientific and Technical Information of China (English)

    李超; 方涛林; 董健

    2011-01-01

    背景:生物可降解材料构建的载生长因子或载生长因子基因的微球已被较多应用于骨组织工程研究中.但载药微球在骨缺损修复中的作用效果不一,受到很多因素的影响.目的:探讨影响骨缺损修复过程中载药微球发挥作用的因素,为载药微球的进一步有效应用奠定基础.方法:通过计算机检索 PubMed 数据库 1999-01/2010-04 的相关文献,检索词为"gene or growth factor, nanosphere or microsphere, bone";同时检索中国期刊全文数据库1999-01/2009-04 的相关文献,检索词为"基因或生长因子、微球、骨",纳入有关载生长因子或生长因子基因的微球在骨缺损修复中应用方面的30篇文章进行综述.结果与结论:微球发挥作用的效率与微球材料、尺寸、表面修饰、所载药物种类及与支架的结合方式等密切相关.目前,对于这些因素的研究仍不够彻底,对它们的控制也还不够理想.调整好这些因素,使载药微球有效应用于骨组织工程,需要更多的研究从各方面进行不断的探索和完善.%BACKGROUND: As carriers of growth factors or genes, microspheres made with artificial biodegradable materials have been used in bone tissue engineering by many researchers. But the effect of these microspheres on bone defects repair is different,and depends on many factors.OBJECTIVE: To discuss the factors that affect the function of drug loaded microspheres in bone defect repair, and to lay a foundation for further effective application of drug loaded microspheres.METHODS: A computer-based online search of PubMed (1999-01/2010-04) and CNKI (1999-01/2010-04) was performed for related articles with the keywords "gene or growth factor, nanosphere or microsphere, bone". Thirty studies about application of growth factors- or genes-loaded microspheres were included.RESULTS AND CONCLUSION: The effect of the drug loaded microspheres is closely related to their material and diameter

  12. Statistical estimation of loads from gas explosions

    Energy Technology Data Exchange (ETDEWEB)

    Hoeiset, Stian

    1998-12-31

    In the design of structures in the offshore and process industries, the possibility of a gas explosion must always be considered. The main uncertainties in computerized simulation of gas explosions are the assumptions of the gas cloud, the location of the ignition point and the properties of the simulator itself. This thesis quantifies the levels of these uncertainties by performing a large number of simulations on three offshore modules and one onshore plant. It is found that (1) there is an approximate linear relation between pressure and gas volume, (2) it may be possible to find a linear relation between pressure and impulse, (3) there is an inverse relation between pressure and duration, (4) the response of offshore structures exposed to gas explosions are rarely in the impulsive regime, (5) loading rates vary widely in magnitude, (6) an assumption of a triangular explosion pulse is often correct, (7) louvres increase pressure, impulse and duration of an explosion. The effect of ignition point location is studied in detail. It is possible to derive an ignition point uncertainty load factor that shows predictable behaviour by generalizing the non-parametric properties of the explosion pressure. A model for taking into account the uncertainties regarding gas volume, ignition point location and simulator imperfectness is proposed. The model is intended to produce a characteristic load for structural design. 68 refs., 51 figs., 36 tabs.

  13. Load Measurements

    DEFF Research Database (Denmark)

    Kock, Carsten Weber; Vesth, Allan

    The report describes Load measurements carried out on a given wind turbine. The aim of the measurement program regarding the loads on the turbine is to verify the basic characteristics of the wind turbine and loads on the blades, the rotor and the tower, using [Ref 1], [Ref2] and [Ref 3]. Regarding...... the fatigue loads, the rotor, blades and tower moments are presented. The fatigue loads are evaluated using rainflow counting described in detail in Ref. [1]. The 1Hz equivalent load ranges are calculated at different wind speeds. All information regarding the instrumentation is collected in [ref 4] and [ref...

  14. Duration judgements over multiple elements

    Directory of Open Access Journals (Sweden)

    Inci eAyhan

    2012-11-01

    Full Text Available We investigated the limits of the number of events observers can simultaneously time. For single targets occurring in one of eight positions sensitivity to duration was improved for spatially pre-cued items as compared to post-cued items indicating that exogenous driven attention can improve duration discrimination. Sensitivity to duration for pre-cued items was also marginally better for single items as compared to eight items indicating that even after the allocation of focal attention, distracter items can interfere with the encoding of duration. For an eight item array discrimination was worse for post-cued locations as compared to pre-cued locations indicating both that attention can improve duration discrimination performance and that it was not possible to access a perfect memory trace of the duration of eight elements. The interference from the distracters in the pre-cued eight item array may reflect some mandatory averaging of target and distracter events. To further explore duration averaging we asked subjects to explicitly compare average durations of multiple item arrays against a single item standard duration. Duration discrimination thresholds were significantly lower for single elements as compared to multiple elements, showing that averaging, either automatically or intentionally, impairs duration discrimination. There was no set size effect. Performance was the same for averages of two and eight items, but performance with even an average of two items was worse than for one item. This was also true for sequential presentation indicating poor performance was not due to limits on the division of attention across items. Rather performance appears to be limited by an inability to remember or aggregate duration information from two or more items. Although it is possible to manipulate perceived duration locally, there appears to be no perceptual mechanisms for aggregating local durations across space.

  15. Factores de Deserción Estudiantil en Ingeniería: Una Aplicación de Modelos de Duración Student Dropout Factors in Engineering: An Application of Duration Models

    Directory of Open Access Journals (Sweden)

    Christian J Díaz

    2009-01-01

    Full Text Available Se analizó la deserción estudiantil universitaria, en estudiantes de carreras de ingeniería de la cohorte del año 2004 hasta enero del año 2007. Se evaluó la retención utilizando un modelo de Kaplan-Meier, y se determinaron factores de la deserción con un modelo de riesgos proporcionales de Cox. Los resultados muestran que la mayor probabilidad de desertar se presenta en los tres primeros semestres, y en estudiantes que provienen de colegios financiados por el estado. Son factores determinantes de la retención un alto promedio ponderado acumulado, disponer de crédito universitario, a mayor puntaje de la prueba de selección universitaria, provenir de un establecimiento educacional de enseñanza media científico-humanista y altos ingresos promedio familiar. Se analiza también los factores de deserción más recurrentes y se proponen medidas para disminuir la deserción estudiantil universitaria.College drop-out of undergraduate engineering students from 2004 until January 2007 was analysed using the Kaplan-Meier model to evaluate the retention rate of students. Drop-out factors were determined using a Cox model for proportional risks. The results show that it is most likely that dropouts take place within the first three terms and mainly affect those students coming from public school, financed by the government. Retention decisive factors are: high average high school grades, access to the national system of university credit, high average grade in the national university selection exam, secondary education with a scientific and humanities oriented curriculum, and high family incomes. The most common drop-out factors are also discussed and solutions to diminish university desertion are proposed.

  16. Factores de Deserción Estudiantil en Ingeniería: Una Aplicación de Modelos de Duración Student Dropout Factors in Engineering: An Application of Duration Models

    OpenAIRE

    Christian J Díaz

    2009-01-01

    Se analizó la deserción estudiantil universitaria, en estudiantes de carreras de ingeniería de la cohorte del año 2004 hasta enero del año 2007. Se evaluó la retención utilizando un modelo de Kaplan-Meier, y se determinaron factores de la deserción con un modelo de riesgos proporcionales de Cox. Los resultados muestran que la mayor probabilidad de desertar se presenta en los tres primeros semestres, y en estudiantes que provienen de colegios financiados por el estado. Son factores determinant...

  17. Three Dimensional Parametric Analyses on Effect of Fibre Orientation for Stress Concentration Factor in Fibrous Composite Cantilever Plate with Central Circular Hole under Transverse Loading

    Directory of Open Access Journals (Sweden)

    Nitin Jain

    2012-10-01

    Full Text Available Normal 0 false false false EN-IN X-NONE X-NONE ABSTRACT: A number of analytical and numerical techniques are available for the two dimensional study of stress concentration around the hole(s in isotropic and composite plates subjected to in-plane or transverse loading conditions. The information on the techniques for three dimensional analyses of stress concentration factor (SCF around the hole in isotropic and composite plates subjected to transverse loading conditions is, however, limited. The present work emphasizes on the effect of fibre orientation (q on the stress concentration factor in fibrous composite plates with central circular hole under transverse static loading condition. The work is carried out for cantilever fibrous composite plates. The effects of thickness -to- width (T/A and diameter-to-width (D/A ratios upon SCF at different fibre orientation are studied. Plates of four different composite materials were considered for hole analysis in order to determine the sensitivity of SCF with elastic constants. Deflections in transverse direction were calculated and analysed. All results are presented in graphical form and discussed. The finite element formulation and its analysis were carried out using ANSYS package.ABSTRAK: Terdapat pelbagai teknik analitikal dan numerical untuk kajian tumpuan tegasan dua dimensi di sekeliling lubang-lubang dalam komposit isotropik dan plat pada satah atau keadaan bebanan melintang. Bagaimanapun, maklumat mengenai kaedah analisis tiga dimensi untuk faktor ketumpatan tegasan (SCF sekitar lubang dalam komposit isotropik dan plat pada keadaan bebanan melintang adalah terhad. Kertas ini menekankan kesan orientasi gentian (q pada faktor tumpuan tegasan dalam komposit plat bergentian dengan lubang berpusat di bawah keadaan bebanan melintang. Kajian ini dilkukan untuk cantilever plat komposit bergentian. Kesan ketebalan terhadap kelebaran plat (T/A dan diameter terhadap kelebaran komposit (D/A dengan SCF

  18. 快速锻造液压机动载因数分析%Dynamic load factor analysis for high-speed forging hydraulic press

    Institute of Scientific and Technical Information of China (English)

    高俊峰; 孙茂; 芦光荣; 刘崇民

    2012-01-01

    通过对20 MN下拉式快锻压机及对液压系统动载分析,介绍了快锻液压机组设计中动载因数的重要性;就如何降低液压冲击及振动提出了分析方法,尤其是分析了液压瞬变与流体在管道内的振动对机械系统振动的影响;提出了快锻液压机组设计中降低动载因数应遵守的准则.分析研究结果对液压系统设计中对泵、阀、管道等组件单元的选型与计算具有指导意义.%The importance of dynamic load factor in design of the high-speed hydraulic forging press was introduced through the dynamic load analysis for 20 MN pull-down type high-speed hydraulic forging press and its hydraulic system. The analytical method for how to reduce the hydraulic impact &- vibration was presented. The effect for the mechanical system vibration was especially analysed when the hydraulic transient and the fluid were vibrating in the piping. The criterion for the reducing dynamic load factor on the design of high-speed hydraulic forging press was provided. The analysis and research results have the guidance means for the model selection and calculation for pump, valve, piping and etc. in the hydraulic system designing.

  19. Load Measurements

    DEFF Research Database (Denmark)

    Vesth, Allan; Kock, Carsten Weber

    The report describes Load measurements carried out on a given wind turbine. The aim of the measurement program regarding the loads on the turbine is to verify the basic characteristics of the wind turbine and loads on the blades, the rotor and the tower, using [Ref 1], [Ref2] and [Ref 3]. Regardi...

  20. Load Measurements

    DEFF Research Database (Denmark)

    Kock, Carsten Weber; Vesth, Allan

    The report describes Load measurements carried out on a given wind turbine. The aim of the measurement program regarding the loads on the turbine is to verify the basic characteristics of the wind turbine and loads on the blades, the rotor and the tower, using [Ref 1], [Ref2] and [Ref 3]. Regarding...

  1. Estimation of C*-Integral in Thin T-Sections Subjected to Projection and Remote Loading Base on Elastic Stress Concentration Factor

    Directory of Open Access Journals (Sweden)

    A. R. Gowhari-Anaraki

    2008-01-01

    Full Text Available The finite element method has been used to predict the creep rupture parameter, C*-Integral of flat T-section bar subjected to loaded projection and remote loading with a crack or crack-like flaw introduced in the fillet (i.e., high stress region of the component. In this study, a new dimensionless creeping crack configuration factor, Q* has been introduced. Power low creeping finite element analyses have been performed and the results are presented in the form of Q* for a wide range of components and crack geometric parameters. These parameters are chosen to be representative of typical practical situations and have been determined from evidence presented in the open literature. The extensive range of Q* obtained from the analyses are then used to obtain equivalent prediction equations using a statistical multiple non-linear regression model. The predictive equations for Q*, which are based on the elastic stress concentration factor, can also be used easily to calculate the C*-Integral values for extensive range of geometric parameters. The C*-Integral values obtained from predictive equations were also compared with those obtained from Reference Stress Method (RSM. Finally, creep zone growth behavior was studied in the component during transient time.

  2. Prevalence and risk factors associated to chronic kidney disease in HIV-infected patients on HAART and undetectable viral load in Brazil.

    Directory of Open Access Journals (Sweden)

    Andréia M Menezes

    Full Text Available BACKGROUND: To determine the prevalence and associated factors with chronic kidney disease (CKD in a cohort of HIV-positive individuals with undetectable viral load on HAART. METHODS: From March, 2009 to September 2009, 213 individuals between 18-70 years, period on HAART ≥12 months, viral load < 50 copies/mm(3, and CD4 ≥ 200 cells/mm(3, were consecutively enrolled at the outpatient clinic of Hospital de Clínicas, Porto Alegre, Brazil. Exclusion criteria were obesity, malnourishment, amputee, paraplegic, previous history of renal disease, pregnancy and hepatic insufficiency. Renal function was determined by estimated glomerular filtration rate (eGFR assessed by the modification of diet in renal disease. CKD was defined as an eGFR less or equal than 60 ml/min/1.73 m(2, for a period of at least 3 months. Poisson regression was used to determine factors associated with CKD. RESULTS: CKD was diagnosed in 8.4% of the population, and after adjustment, the risk factors were hypertension (RR = 3.88, 95%CI, 1.84-8.16, time on HAART (RR = 1.15, 95%CI,1.03-1.27 and tenofovir exposure (RR = 2.25, 95%CI, 1.04-4.95. Higher weight (RR = 0.88 95%CI, 0.82-0.96 was associated to normal function. CONCLUSIONS: CKD was a common finding in this cohort of patients and was related to hypertension, time on HAART and tenofovir exposure. We suggest a more frequent monitoring of renal function, especially for those with risk factors to early identify renal impairment.

  3. Factors Affecting Microbial Load and Profile of Potential Pathogens and Food Spoilage Bacteria from Household Kitchen Tables.

    Science.gov (United States)

    Biranjia-Hurdoyal, Susheela; Latouche, Melissa Cathleen

    2016-01-01

    The aim was to study the bacterial load and isolate potential pathogens and food spoilage bacteria from kitchen tables, including preparation tables and dining tables. Methods. A total of 53 households gave their consent for participation. The samples were collected by swabbing over an area of 5 cm by 5 cm of the tables and processed for bacterial count which was read as colony forming units (CFU), followed by isolation and identification of potential pathogens and food spoilage bacteria. Result. Knowledge about hygiene was not always put into practice. Coliforms, Enterococcus spp., Pseudomonas spp., Proteus spp., and S. aureus were detected from both dining and preparation tables. The mean CFU and presence of potential pathogens were significantly affected by the hygienic practices of the main food handler of the house, materials of kitchen tables, use of plastic covers, time of sample collection, use of multipurpose sponges/towels for cleaning, and the use of preparation tables as chopping boards (p Kitchen tables could be very important source of potential pathogens and food spoilage bacteria causing foodborne diseases. Lack of hygiene was confirmed by presence of coliforms, S. aureus, and Enterococcus spp. The use of plastic covers, multipurpose sponges, and towels should be discouraged.

  4. Proliferation of endothelial cells on surface-immobilized albumin-heparin conjugate loaded with basic fibroblast growth factor

    NARCIS (Netherlands)

    Bos, Gert W.; Scharenborg, Nicole M.; Poot, André A.; Engbers, Gerard H.M.; Beugeling, Tom; Aken, van Willem G.; Feijen, Jan

    1999-01-01

    Seeding of endothelial cells (ECs) on the luminal surface of small-diameter vascular grafts is a promising method to avoid occlusion of these prostheses. Immobilization of basic fibroblast growth factor (bFGF) to substrates used to coat or fill porous prostheses may enhance the formation of a conflu

  5. Impact of response duration on multisensory integration

    Science.gov (United States)

    Barnett, Zachary P.; Wallace, Mark T.

    2012-01-01

    Multisensory neurons in the superior colliculus (SC) have been shown to have large receptive fields that are heterogeneous in nature. These neurons have the capacity to integrate their different sensory inputs, a process that has been shown to depend on the physical characteristics of the stimuli that are combined (i.e., spatial and temporal relationship and relative effectiveness). Recent work has highlighted the interdependence of these factors in driving multisensory integration, adding a layer of complexity to our understanding of multisensory processes. In the present study our goal was to add to this understanding by characterizing how stimulus location impacts the temporal dynamics of multisensory responses in cat SC neurons. The results illustrate that locations within the spatial receptive fields (SRFs) of these neurons can be divided into those showing short-duration responses and long-duration response profiles. Most importantly, discharge duration appears to be a good determinant of multisensory integration, such that short-duration responses are typically associated with a high magnitude of multisensory integration (i.e., superadditive responses) while long-duration responses are typically associated with low integrative capacity. These results further reinforce the complexity of the integrative features of SC neurons and show that the large SRFs of these neurons are characterized by vastly differing temporal dynamics, dynamics that strongly shape the integrative capacity of these neurons. PMID:22896723

  6. Ultrasound-targeted stromal cell-derived factor-1-loaded microbubble destruction promotes mesenchymal stem cell homing to kidneys in diabetic nephropathy rats.

    Science.gov (United States)

    Wu, Shengzheng; Li, Lu; Wang, Gong; Shen, Weiwei; Xu, Yali; Liu, Zheng; Zhuo, Zhongxiong; Xia, Hongmei; Gao, Yunhua; Tan, Kaibin

    2014-01-01

    Mesenchymal stem cell (MSC) therapy has been considered a promising strategy to cure diabetic nephropathy (DN). However, insufficient MSCs can settle in injured kidneys, which constitute one of the major barriers to the effective implementation of MSC therapy. Stromal cell-derived factor-1 (SDF-1) plays a vital role in MSC migration and involves activation, mobilization, homing, and retention, which are presumably related to the poor homing in DN therapy. Ultrasound-targeted microbubble destruction has become one of the most promising strategies for the targeted delivery of drugs and genes. To improve MSC homing to DN kidneys, we present a strategy to increase SDF-1 via ultrasound-targeted microbubble destruction. In this study, we developed SDF-1-loaded microbubbles (MB(SDF-1)) via covalent conjugation. The characterization and bioactivity of MB(SDF-1) were assessed in vitro. Target release in the targeted kidneys was triggered with diagnostic ultrasound in combination with MB(SDF-1). The related bioeffects were also elucidated. Early DN was induced in rats with streptozotocin. Green fluorescent protein-labeled MSCs were transplanted intravenously following the target release of SDF-1 in the kidneys of normal and DN rats. The homing efficacy was assessed by detecting the implanted exogenous MSCs at 24 hours. The in vitro results showed an impressive SDF-1 loading efficacy of 79% and a loading content of 15.8 μg/mL. MB(SDF-1) remained bioactive as a chemoattractant. In the in vivo study, SDF-1 was successfully released in the targeted kidneys. The homing efficacy of MSCs to DN kidneys after the target release of SDF-1 was remarkably ameliorated at 24 hours compared with control treatments in normal rats and DN rats. In conclusion, ultrasound-targeted MB(SDF-1) destruction could promote the homing of MSCs to early DN kidneys and provide a novel potential therapeutic approach for DN kidney repair.

  7. Usual dietary glycemic load is associated with cardiometabolic risk factors in physically active Brazilian middle-aged men.

    Science.gov (United States)

    Cocate, Paula G; Natali, Antônio J; de Oliveira, Alessandro; Hermsdorff, Helen Hermana M; Peluzio, Maria do Carmo G; Longo, Giana Z; Buthers, Jéssica M; dos Santos, Eliziária C; de Oliveira, Leandro L; Alfenas, Rita de Cássia G

    2014-02-01

    Introducción: Los efectos de la carga glucémica (CG) de la dieta sobre los factores de riesgo cardiometabólico en sujetos físicamente activos no están establecidos por completo. Objetivo: Este estudio transversal evaluó la asociación entre la CG de la dieta habitual y los factores de riesgo cardiometabólico en hombres brasileños de mediana edad físicamente activos. Métodos: Ciento setenta y seis sujetos (índice de masa corporal: 25,5 ± 3,6 kg/m2; edad: 50,6 ± 5,0 años) fueron evaluados. Antropometría, características del estilo de vida, la resistencia a la insulina, biomarcadores del estrés oxidativo (8-iso-prostaglandina F2, 8-iso-PGF2y 8 hidroxideoxiguanosina, 8-OHdG) y el perfil lipídico fueron evaluados. La ingesta dietética se estimó por medio de un cuestionario cuantitativo de frecuencia de consumo. Resultados: La CG de la dieta se asoció positivamente con las concentraciones de ácidos grasos libres (= 0,311, r2 = 0,13, P = 0,034) y la razón triglicéridos/colesterol HDL (= 0,598, r2 = 0,19, P = 0,028), independientemente de los factores de confusión (obesidad central, consumo de carne roja, edad e ingesta calórica). El biomarcador del estrés oxidativo, 8-OHdG, también se asoció con CG de la dieta habitual (= 0,432, r2 = 0,11, P = 0,004), independientemente de los factores de confusión anteriores más el consumo excesivo de alcohol, la ingesta de hierro y tabaquismo actual. Conclusiones: La CG de la dieta se asoció positivamente con el perfil lipídico (concentraciones de ácidos grasos libres y razón triglicéridos/HDL colesterol) y el biomarcador de estrés oxidativo 8-OHdG. Estos resultados indican el potencial de nocividad de una dieta con mayor CG respecto a los factores de riesgo cardiometabólico en hombres de mediana edad, incluso en aquellos físicamente activos.

  8. Transient Monotonic and Cyclic Load Effects on Mono Bucket Foundations

    DEFF Research Database (Denmark)

    Nielsen, Søren Dam

    and when hitting the foundation they induce high impact loads with a short duration. It is important that the foundation is able to resists these huge loads. Fortunately, the conducted research showed that the capacity of the mono bucket foundation is high to impact loads. When exposed to a huge wave load...

  9. Identification of the Uncertainties for the Calibration of the Partial Safety Factors for Load in Tidal Turbines

    Directory of Open Access Journals (Sweden)

    Gaizka Zarraonandia Simeón

    2016-03-01

    Full Text Available Tidal energy is nowadays one of the fastest growing types of marine renewable energy. In particular, Horizontal Axis Tidal Turbines (HATTs are the most advanced designs and the most appropriate for standardization. This paper presents a review of actual design criteria focusing on the identification of the uncertainties that technology developers need to address during the design process. Key environmental parameters like turbine inflow conditions or predictions of extreme values are still grey areas due to the lack of site measurements and the uncertainty in metocean model predictions. A comparison of turbulence intensity characterization using different tools and at different points in time shows the uncertainty in the prediction of this parameter. Numerical models of HATTs are still quite uncertain, often dependent on experience of the people running them. In the reliability-based calibration of partial safety factors, the uncertainties need to be reflected on the limit state formulation. This paper analyses the different types of uncertainties present in the limit state equation. These uncertainties are assessed in terms of stochastic variables in the limit state equation. In some cases, advantage can be taken from the experience from offshore wind and oil and gas industries. Tidal turbines have a mixture of the uncertainties present in both industries with regard to partial safety factor calibration.

  10. Interaction of Mechanical Load with Growth Hormone (GH) and Insulin-Like Growth Factor I (IGF-I) on Slow-Twitch Skeletal Muscle and Bone

    Science.gov (United States)

    Linderman, Jon K.; Gosselink, Kristin L.; Wang, Tommy J.; Mukku, Venkat R.; Grindeland, Richard E.

    1994-01-01

    Exogenous humoral growth factors, combined with increased mechanical loading, reportedly induce hypertrophy of fast-, but not slow-twitch skeletal muscles, and have little effect in attenuating atrophy of slow-twitch muscle associated with exposure to microgravity in animals with intact neuroendocrine systems. These observations suggest that anabolic adjuvants and muscle tension do not interact to stimulate growth or maintenance of slow-twitch skeletal muscle. The purpose of the present study was to determine whether a chronic increase in mechanical loading (synergistic ablation) or hindlimb unweighting (hindlimb suspension) interact with exogenous GH and IGF-I (Genentech, So San Francisco, CA) in the slow-twitch soleus muscles of female rats (approx. 250 g). Bilateral ablation of the plantaris and gastrocnemius muscles induced 38% and 40% increases in the absolute (mg/pair) and relative (mg/100 g body weight) weights of the soleus, respectively (p less than or = 0.05), in ambulatory rats. GH and IGF-I interacted with chronic loading to increase absolute soleus mass an additional 20% (p less than or = 0.05), and mixed and myofibrillar protein contents an additional 12% and 7%, respectively (NS). In contrast, hindlimb suspension (HLS) resulted in 20% and 18% decreases in the absolute and relative weights of the soleus, respectively (p less than or = 0.05); GH and IGF-I did not spare loss of soleus mass or protein content in HLS rats. HLS decreased tibial plate thickness approx. 11% (p less than or = 0.05), but not weights of the tibia or femus. GH and IGF-I increased tibial plate thickness approx. 30% (p less than or = 0.05), in ambulatory and HLS rats, and increased femur and tibial weights 12% (p less than or = 0.05) and 8% (NS), respectively, in ambulatory rats, but had no effect in HLS rats. Results of the present investigation suggest that GH and IGF-I can stimulate hypertrophy of slow-twitch skeletal muscle when chronically overloaded, but can also stimulate

  11. Interaction of Mechanical Load with Growth Hormone (GH) and Insulin-Like Growth Factor I (IGF-I) on Slow-Twitch Skeletal Muscle and Bone

    Science.gov (United States)

    Linderman, Jon K.; Gosselink, Kristin L.; Wang, Tommy J.; Mukku, Venkat R.; Grindeland, Richard E.

    1994-01-01

    Exogenous humoral growth factors, combined with increased mechanical loading, reportedly induce hypertrophy of fast-, but not slow-twitch skeletal muscles, and have little effect in attenuating atrophy of slow-twitch muscle associated with exposure to microgravity in animals with intact neuroendocrine systems. These observations suggest that anabolic adjuvants and muscle tension do not interact to stimulate growth or maintenance of slow-twitch skeletal muscle. The purpose of the present study was to determine whether a chronic increase in mechanical loading (synergistic ablation) or hindlimb unweighting (hindlimb suspension) interact with exogenous GH and IGF-I (Genentech, So San Francisco, CA) in the slow-twitch soleus muscles of female rats (approx. 250 g). Bilateral ablation of the plantaris and gastrocnemius muscles induced 38% and 40% increases in the absolute (mg/pair) and relative (mg/100 g body weight) weights of the soleus, respectively (p less than or = 0.05), in ambulatory rats. GH and IGF-I interacted with chronic loading to increase absolute soleus mass an additional 20% (p less than or = 0.05), and mixed and myofibrillar protein contents an additional 12% and 7%, respectively (NS). In contrast, hindlimb suspension (HLS) resulted in 20% and 18% decreases in the absolute and relative weights of the soleus, respectively (p less than or = 0.05); GH and IGF-I did not spare loss of soleus mass or protein content in HLS rats. HLS decreased tibial plate thickness approx. 11% (p less than or = 0.05), but not weights of the tibia or femus. GH and IGF-I increased tibial plate thickness approx. 30% (p less than or = 0.05), in ambulatory and HLS rats, and increased femur and tibial weights 12% (p less than or = 0.05) and 8% (NS), respectively, in ambulatory rats, but had no effect in HLS rats. Results of the present investigation suggest that GH and IGF-I can stimulate hypertrophy of slow-twitch skeletal muscle when chronically overloaded, but can also stimulate

  12. Effect of water deprivation, desmopressin (DDAVP) infusion, and oral loads of water, Na+ and NH4+ on urinary excretion of epidermal growth factor in the rat

    DEFF Research Database (Denmark)

    Jørgensen, P E; Poulsen, Steen Seier; Nexø, Ebba

    1993-01-01

    Epidermal growth factor (EGF) is synthesized in the kidneys and excreted in urine. Administration of exogenous EGF modulates the reabsorption of Na+ and the vasopressin stimulated reabsorption of water in the collecting tubules. In order to clarify whether this reflects a physiological role...... for urinary EGF we examined the effects of changes in the oral loads of water, Na+ and NH4+ as well as the effect of infusion of the vasopressin analogue, desmopressin (DDAVP) on the endogenous urinary EGF excretion in the rat. Water deprivation for 48 h reduced the urinary excretion of EGF by 25......% and the urinary EGF/creatinine ratio by 8%. Also, urinary volume, Na+ excretion, and urinary pH were reduced by water deprivation. Infusion of DDAVP, low plasma vasopressin induced by polydipsia, and changes in the renal excretion of Na+ and H+ did not affect the urinary excretion of EGF. In conclusion: it seems...

  13. Voltage-Sharing Converter to Supply Single-Phase Asymmetrical Four-Level Diode-Clamped Inverter With High Power Factor Loads

    DEFF Research Database (Denmark)

    Boora, Arash A.; Nami, Alireza; Zare, Firuz

    2010-01-01

    The output voltage quality of some of the single-phase multilevel inverters can be improved when their dc-link voltages are regulated asymmetrically. Symmetrical and asymmetrical multilevel diode-clamped inverters have the problem of dc-link capacitor voltage balancing, especially when power factor...... of the load is close to unity. In this paper, a new single-inductor multi-output dc/dc converter is proposed that can control the dc-link voltages of a single-phase diode-clamped inverter asymmetrically to achieve voltage quality enhancement. The circuit of the presented converter is explained and the main...... equations are developed. A control strategy is proposed and explained in details. To validate the versatility of the proposed combination of the suggested dc–dc converter and the asymmetrical four-level diode-clamped inverter (ADCI), simulations and experiments have been directed. It is concluded...

  14. Influence of fuel mass load, oxygen supply and burning rate on emission factor and size distribution of carbonaceous particulate matter from indoor corn straw burning

    Institute of Scientific and Technical Information of China (English)

    Guofeng Shen; Miao Xue; Siye Wei; Yuanchen Chen; Bin Wang; Rong Wang; Huizhong Shen

    2013-01-01

    The uncertainty in emission estimation is strongly associated with the variation in emission factor (EF),which could be influenced bya variety of factors such as fuel properties,stove type,fire management and even methods used in measurements.The impacts of thesefactors are complicated and often interact with each other.Controlled burning experiments were conducted to investigate the influencesof fuel mass load,air supply and burning rate on the emissions and size distributions of carbonaceous particulate matter (PM) fromindoor corn straw bunting in a cooking stove.The results showed that the EFs of PM (EFpM),organic carbon (EFoc) and elementalcarbon (EFEc) were independent of the fuel mass load.The differences among them under different burning rates or air supply amountswere also found to be insignificant (P > 0.05) in the tested circumstances.PM from the indoor corn straw burning was dominated byfine PM with diameter less than 2.1 μm,contributing 86.4% ± 3.9% of the total.The size distribution of PM was influenced by theburning rate and air supply conditions.On average,EFPM,EFoc and EFEC for corn straw burned in a residential cooking stove were(3.84 ± 1.02),(0.846 ± 0.895) and (0.391 ± 0.350) g/kg,respectively.EFPM,EFoc and EFEc were found to be positively correlatedwith each other (P < 0.05),but they were not significantly correlated with the EF of co-emitted CO,suggesting that special attentionshould be paid to the use of CO as a surrogate for other incomplete combustion pollutants.

  15. Accelerated evolution of functional plastid rRNA and elongation factor genes due to reduced protein synthetic load after the loss of photosynthesis in the chlorophyte alga Polytoma.

    Science.gov (United States)

    Vernon, D; Gutell, R R; Cannone, J J; Rumpf, R W; Birky, C W

    2001-09-01

    Polytoma obtusum and Polytoma uvella are members of a clade of nonphotosynthetic chlorophyte algae closely related to Chlamydomonas humicola and other photosynthetic members of the Chlamydomonadaceae. Descended from a nonphotosynthetic mutant, these obligate heterotrophs retain a plastid (leucoplast) with a functional protein synthetic system, and a plastid genome (lpDNA) with functional genes encoding proteins required for transcription and translation. Comparative studies of the evolution of genes in chloroplasts and leucoplasts can identify modes of selection acting on the plastid genome. Two plastid genes--rrn16, encoding the plastid small-subunit rRNA, and tufA, encoding elongation factor Tu--retain their functions in protein synthesis after the loss of photosynthesis in two nonphotosynthetic Polytoma clades but show a substantially accelerated rate of base substitution in the P. uvella clade. The accelerated evolution of tufA is due, at least partly, to relaxed codon bias favoring codons that can be read without wobble, mainly in three amino acids. Selection for these codons may be relaxed because leucoplasts are required to synthesize fewer protein molecules per unit time than are chloroplasts (reduced protein synthetic load) and thus require a lower rate of synthesis of elongation factor Tu. Relaxed selection due to a lower protein synthetic load is also a plausible explanation for the accelerated rate of evolution of rrn16, but the available data are insufficient to test the hypothesis for this gene. The tufA and rrn16 genes in Polytoma oviforme, the sole member of a second nonphotosynthetic clade, are also functional but show no sign of relaxed selection.

  16. Combination of external loads

    Energy Technology Data Exchange (ETDEWEB)

    Frandsen, S.; Tarp Johansen, N.J.; Joergensen, H. [Forskningscenter Risoe, Roskilde (Denmark); Gravesen, H.; Soerensen, S.L. [Carl Bro, Glostrup (Denmark); Pedersen, J. [Elsam Engineering, Fredericia (Denmark); Zorn, R.; Hvidberg Knudsen, M. [DHI Water and Environment, Hoersholm (Denmark); Voelund, P. [Energi E2, Koebenhavn (Denmark)

    2003-09-01

    The project onbectives have been: To improve and consequently opimise the basis for design of offshore wind turbines. This is done through 1) mapping the wind, wave ice and current as well as correlations of these, and 2) by clarifyring how these external conditions transform into loads. A comprehensive effort has been made to get a thorough understanding of the uncertainties that govern the reliability of wind turbines with respect to wind and wave loading. One of the conclusions is that the reliability of wind turbines is generally lower, than the average reliability of building structures that are subject not only to environmental loads, which are very uncertain, but also imposed loads and self weight, which are less uncertain than the environmental loads. The implication is that, at the moment lower load partial safety factors for onshore wind turbines cannot be recommended. For the combination of wind and wave design loads the problem is twofold: 1). A very conservative design will be generated by simply adding the individual wind and wave design loads disregarding the independence of the short-term fluctuations of wind and wave loads. 2). Characteristic values and partial safety factors for wind and wave loads are not defined similarly. This implies that the reliability levels of turbine support structures subject to purely aerodynamic loads and subject to purely hydrodynamic loads are not identical. For the problem of combining aerodynamic design loads and hydrodynamic design loads two results have been obtained in the project: 1). By simple means a site specific wave load safety factor rendering the same safety level for hydrodynamic loads as for aerodynamic loads is derived, and next, by direct square summation of extreme fluctuations, the wind and wave load safety factors are weighted. 2). Under the assumptions that a deep water site is considered and that the wave loading is a fifty-fifty mix of drag and inertia the same wind and wave load safety factor

  17. Ultrasound-targeted stromal cell-derived factor-1-loaded microbubble destruction promotes mesenchymal stem cell homing to kidneys in diabetic nephropathy rats

    Directory of Open Access Journals (Sweden)

    Wu S

    2014-12-01

    Full Text Available Shengzheng Wu,1 Lu Li,1 Gong Wang,1 Weiwei Shen,2 Yali Xu,1 Zheng Liu,1 Zhongxiong Zhuo,1 Hongmei Xia,1 Yunhua Gao,1 Kaibin Tan1 1Department of Ultrasound, 2Department of Orthopedics, Xinqiao Hospital, Third Military Medical University, Chongqing, People’s Republic of China Abstract: Mesenchymal stem cell (MSC therapy has been considered a promising strategy to cure diabetic nephropathy (DN. However, insufficient MSCs can settle in injured kidneys, which constitute one of the major barriers to the effective implementation of MSC therapy. Stromal cell-derived factor-1 (SDF-1 plays a vital role in MSC migration and involves activation, mobilization, homing, and retention, which are presumably related to the poor homing in DN therapy. Ultrasound-targeted microbubble destruction has become one of the most promising strategies for the targeted delivery of drugs and genes. To improve MSC homing to DN kidneys, we present a strategy to increase SDF-1 via ultrasound-targeted microbubble destruction. In this study, we developed SDF-1-loaded microbubbles (MBSDF-1 via covalent conjugation. The characterization and bioactivity of MBSDF-1 were assessed in vitro. Target release in the targeted kidneys was triggered with diagnostic ultrasound in combination with MBSDF-1. The related bioeffects were also elucidated. Early DN was induced in rats with streptozotocin. Green fluorescent protein-labeled MSCs were transplanted intravenously following the target release of SDF-1 in the kidneys of normal and DN rats. The homing efficacy was assessed by detecting the implanted exogenous MSCs at 24 hours. The in vitro results showed an impressive SDF-1 loading efficacy of 79% and a loading content of 15.8 µg/mL. MBSDF-1 remained bioactive as a chemoattractant. In the in vivo study, SDF-1 was successfully released in the targeted kidneys. The homing efficacy of MSCs to DN kidneys after the target release of SDF-1 was remarkably ameliorated at 24 hours compared with

  18. Synthesizing controllers from duration calculus

    DEFF Research Database (Denmark)

    Fränzle, Martin

    1996-01-01

    Duration Calculus is a logic for reasoning about requirements for real-time systems at a high level of abstraction from operational detail, which qualifies it as an interesting starting point for embedded controller design. Such a design activity is generally thought to aim at a control device...... the physical behaviours of which satisfy the requirements formula, i.e. the refinement relation between requirements and implementations is taken to be trajectory inclusion. Due to the abstractness of the vocabulary of Duration Calculus, trajectory inclusion between control requirements and controller designs...... for embedded controller design and exploit this fact for developing an automatic procedure for controller synthesis from specifications formalized in Duration Calculus. As far as we know, this is the first positive result concerning feasibility of automatic synthesis from dense-time Duration Calculus....

  19. LOG DURATION EMERGENCY OXYGEN BACKPACK.

    Science.gov (United States)

    A small backpack , for use by Naval aviators, containing a long duration emergency oxygen system and a separate humidifier for the aircraft’s oxygen supply, has been devised and a feasibility model built. (Author)

  20. Hazard based models for freeway traffic incident duration.

    Science.gov (United States)

    Tavassoli Hojati, Ahmad; Ferreira, Luis; Washington, Simon; Charles, Phil

    2013-03-01

    Assessing and prioritising cost-effective strategies to mitigate the impacts of traffic incidents and accidents on non-recurrent congestion on major roads represents a significant challenge for road network managers. This research examines the influence of numerous factors associated with incidents of various types on their duration. It presents a comprehensive traffic incident data mining and analysis by developing an incident duration model based on twelve months of incident data obtained from the Australian freeway network. Parametric accelerated failure time (AFT) survival models of incident duration were developed, including log-logistic, lognormal, and Weibul-considering both fixed and random parameters, as well as a Weibull model with gamma heterogeneity. The Weibull AFT models with random parameters were appropriate for modelling incident duration arising from crashes and hazards. A Weibull model with gamma heterogeneity was most suitable for modelling incident duration of stationary vehicles. Significant variables affecting incident duration include characteristics of the incidents (severity, type, towing requirements, etc.), and location, time of day, and traffic characteristics of the incident. Moreover, the findings reveal no significant effects of infrastructure and weather on incident duration. A significant and unique contribution of this paper is that the durations of each type of incident are uniquely different and respond to different factors. The results of this study are useful for traffic incident management agencies to implement strategies to reduce incident duration, leading to reduced congestion, secondary incidents, and the associated human and economic losses.

  1. Characteristics and influencing factors in duration of untreated schizophrenia in Xi'an%西安市精神分裂症患者未治期特点及影响因素

    Institute of Scientific and Technical Information of China (English)

    王峥; 张超; 吴斌; 张珍珍; 梁小平

    2016-01-01

    Objective To investigate the characteristics and influencing factors in duration of un-treated psychosis (DUP) in Xi'an ,and analyze the main reasons that affect patients did not receive treat-ment ,review and rehabilitation .Methods Totals of 1 581 patients with schizophrenia and their family members in Xi'an were investigated by using multi - stage stratified random sampling .The data were an-alyzed by using descriptive and chi - square test .Results The median of DUP was 30 days in all patients with schizophrenia .The main influence of DUP were stigma ,pray ,living style and family type .The main reasons of no active treatment were economic problems and mild thought on illness ;the reasons of unreview were illness cured and economic problems ;the reasons of no rehabilitation were economic prob-lems ,and having no knowledge of rehabilitation therapy .Conclusions The health education of patients and their families still need to be strengthened ,and health policy support should be further implemented .%目的:了解西安市精神分裂症患者未治期(DUP)特点、影响因素,分析患者未积极接受治疗、复查、康复的主要原因。方法采用多阶段分层随机抽样法,对西安市1581例精神分裂症患者及其家属进行问卷调查,主要运用描述性统计和χ2检验对数据进行分析。结果被调查的1581例精神分裂症患者未治期中位数为30 d 。影响未治期的因素主要有病耻感、求神拜佛、居住方式、家庭类型。未积极治疗的主要原因为经济问题、自认为病情轻;没有复查的主要原因是自认为病情痊愈、经济问题;未接受康复治疗的主要原因是经济问题、不知道需要接受康复治疗。结论患者及其家属的健康教育工作仍需加强,卫生政策支持需进一步落实。

  2. Duration of untreated psychosis and the related factors among Tibetan patients with schizophrenia in Qing- hai%青海省藏族精神分裂症未治期及影响因素分析

    Institute of Scientific and Technical Information of China (English)

    李少华; 马弘; 王勋; 管丽丽; 韩国玲; 宋志强

    2016-01-01

    目的:探讨藏族精神分裂症患者精神病未治期(duration of untreated psychosis,DUP)的影响因素。方法采用精神分裂症患者精神卫生服务利用调查问卷及精神分裂症首发症状评定量表对188例藏族精神分裂症患者的社会人口学资料、精神疾病家族史、家庭类型、起病形式、医疗付款方式、居住地、自评家庭收入水平、首发症状出现的时间等进行调查,分析DUP影响因素。结果患者DUP呈偏态分布,中位数375 d(QL=4 d, QU=1661 d)。将患者分为短DUP组(DUP≤375 d)90例和长DUP组(DUP>375 d)98例,不同DUP组患者的起病形式、婚姻状况、文化程度、家庭类型、居住地的组间差异有统计学意义(P375 days, 98 patients). There were significant differences in mode of onset,marital status, educational level, family type, place of residence between short DUP group and long DUP group (P<0.05). Logistic regression analysis found that lack of family structure (OR=2.340, 95%CI:1.130~4.847, P=0.022), chronic onset (OR=2.136, 95%CI:1.172~3.891, P=0.013) and living in pastoral areas (OR=2.239, 95%CI:1.097~4.571, P=0.027) were risk factors of DUP. Conclusion Ti⁃betan patients with schizophrenia have a longer DUP and related risk factories of DUP are lack of family structure, chron⁃ic onset and living in pastoral areas.

  3. Post-meal responses of elongation factor 2 (eEF2) and adenosine monophosphate-activated protein kinase (AMPK) to leucine and carbohydrate supplements for regulating protein synthesis duration and energy homeostasis in rat skeletal muscle.

    Science.gov (United States)

    Wilson, Gabriel J; Moulton, Christopher J; Garlick, Peter J; Anthony, Tracy G; Layman, Donald K

    2012-11-13

    Previous research demonstrates that the anabolic response of muscle protein synthesis (MPS) to a meal is regulated at the level of translation initiation with signals derived from leucine (Leu) and insulin to activate mTORC1 signaling. Recent evidence suggests that the duration of the meal response is limited by energy status of the cell and inhibition of translation elongation factor 2 (eEF2). This study evaluates the potential to extend the anabolic meal response with post-meal supplements of Leu or carbohydrates. Adult (~256 g) male Sprague-Dawley rats were food deprived for 12 h, then either euthanized before a standard meal (time 0) or at 90 or 180 min post-meal. At 135 min post-meal, rats received one of five oral supplements: 270 mg leucine (Leu270), 80:40:40 mg leucine, isoleucine, and valine (Leu80), 2.63 g carbohydrates (CHO2.6), 1 g carbohydrates (CHO1.0), or water (Sham control). Following the standard meal, MPS increased at 90 min then declined to pre-meal baseline at 180 min. Rats administered Leu270, Leu80, CHO2.6, or CHO1.0 maintained elevated rates of MPS at 180 min, while Sham controls declined from peak values. Leu80 and CHO1.0 treatments maintained MPS, but with values intermediate between Sham controls and Leu270 and CHO2.6 supplements. Consistent with MPS findings, the supplements maintained elongation activity and cellular energy status by preventing increases in AMP/ATP and phosphorylation of adenosine monophosphate-activated protein kinase (AMPK), acetyl-CoA carboxylase ACC and eEF2. The impact of the supplements on MPS and cellular energy status was in proportion to the energy content within the individual treatments (i.e., Leu270 > Leu80; CHO2.6 > CHO1.0), but the Leu supplements produced a disproportionate anabolic stimulation of MPS, eEF2 and energy status with significantly lower energy content. In summary, the incongruity between MPS and translation initiation at 180 min reflects a block in translation elongation due to reduced

  4. Post-Meal Responses of Elongation Factor 2 (eEF2 and Adenosine Monophosphate-Activated Protein Kinase (AMPK to Leucine and Carbohydrate Supplements for Regulating Protein Synthesis Duration and Energy Homeostasis in Rat Skeletal Muscle

    Directory of Open Access Journals (Sweden)

    Donald K. Layman

    2012-11-01

    Full Text Available Previous research demonstrates that the anabolic response of muscle protein synthesis (MPS to a meal is regulated at the level of translation initiation with signals derived from leucine (Leu and insulin to activate mTORC1 signaling. Recent evidence suggests that the duration of the meal response is limited by energy status of the cell and inhibition of translation elongation factor 2 (eEF2. This study evaluates the potential to extend the anabolic meal response with post-meal supplements of Leu or carbohydrates. Adult (~256 g male Sprague-Dawley rats were food deprived for 12 h, then either euthanized before a standard meal (time 0 or at 90 or 180 min post-meal. At 135 min post-meal, rats received one of five oral supplements: 270 mg leucine (Leu270, 80:40:40 mg leucine, isoleucine, and valine (Leu80, 2.63 g carbohydrates (CHO2.6, 1 g carbohydrates (CHO1.0, or water (Sham control. Following the standard meal, MPS increased at 90 min then declined to pre-meal baseline at 180 min. Rats administered Leu270, Leu80, CHO2.6, or CHO1.0 maintained elevated rates of MPS at 180 min, while Sham controls declined from peak values. Leu80 and CHO1.0 treatments maintained MPS, but with values intermediate between Sham controls and Leu270 and CHO2.6 supplements. Consistent with MPS findings, the supplements maintained elongation activity and cellular energy status by preventing increases in AMP/ATP and phosphorylation of adenosine monophosphate-activated protein kinase (AMPK, acetyl-CoA carboxylase ACC and eEF2. The impact of the supplements on MPS and cellular energy status was in proportion to the energy content within the individual treatments (i.e., Leu270 > Leu80; CHO2.6 > CHO1.0, but the Leu supplements produced a disproportionate anabolic stimulation of MPS, eEF2 and energy status with significantly lower energy content. In summary, the incongruity between MPS and translation initiation at 180 min reflects a block in translation elongation due to

  5. 非线性负荷条件下的电压不平衡度探讨%Study on Voltage Unbalance Factor under Nonlinear Load

    Institute of Scientific and Technical Information of China (English)

    吕强; 徐晔; 王金全; 宋鹏超

    2013-01-01

    Damages caused by the unbalance of harmonic voltage in a low-voltage distribution system are discussed, the application principle of the symmetrical component method based on harmonics is analyzed; taking into account the regulations on voltage unbalance factor specified in national standard, the definition of the comprehensive unbalance factor of negative-sequence voltage and that of zero-sequence voltage are studied; the correctness of the theoretical analysis is proved by experiments; and the necessity of considering the unbalance of the harmonic voltage under nonlinear load is revealed through analysis.%阐述低压配电系统中谐波电压不平衡带来的危害,分析对称分量法在谐波条件下的应用原理;针对国家标准对电压不平衡度的规定,探讨负序电压综合不平衡度与零序电压综合不平衡度的定义;用实验证明理论分析的正确性;通过分析指出非线性负荷条件下考虑谐波电压不平衡的必要性。

  6. Modeling drivers' passing duration and distance in a virtual environment

    Directory of Open Access Journals (Sweden)

    Haneen Farah

    2013-07-01

    The main contribution of this paper is in the empirical models developed for passing duration and distance which highlights the factors that affect drivers' passing behavior and can be used to enhance the passing models in simulation programs.

  7. Replication factor C from the hyperthermophilic archaeon Pyrococcus abyssi does not need ATP hydrolysis for clamp-loading and contains a functionally conserved RFC PCNA-binding domain.

    Science.gov (United States)

    Henneke, Ghislaine; Gueguen, Yannick; Flament, Didier; Azam, Philippe; Querellou, Joël; Dietrich, Jacques; Hübscher, Ulrich; Raffin, Jean-Paul

    2002-11-08

    The molecular organization of the replication complex in archaea is similar to that in eukaryotes. Only two proteins homologous to subunits of eukaryotic replication factor C (RFC) have been detected in Pyrococcus abyssi (Pab). The genes encoding these two proteins are arranged in tandem. We cloned these two genes and co-expressed the corresponding recombinant proteins in Escherichia coli. Two inteins present in the gene encoding the small subunit (PabRFC-small) were removed during cloning. The recombinant protein complex was purified by anion-exchange and hydroxyapatite chromatography. Also, the PabRFC-small subunit could be purified, while the large subunit (PabRFC-large) alone was completely insoluble. The highly purified PabRFC complex possessed an ATPase activity, which was not enhanced by DNA. The Pab proliferating cell nuclear antigen (PCNA) activated the PabRFC complex in a DNA-dependent manner, but the PabRFC-small ATPase activity was neither DNA-dependent nor PCNA-dependent. The PabRFC complex was able to stimulate PabPCNA-dependent DNA synthesis by the Pabfamily D heterodimeric DNA polymerase. Finally, (i) the PabRFC-large fraction cross-reacted with anti-human-RFC PCNA-binding domain antibody, corroborating the conservation of the protein sequence, (ii) the human PCNA stimulated the PabRFC complex ATPase activity in a DNA-dependent way and (iii) the PabRFC complex could load human PCNA onto primed single-stranded circular DNA, suggesting that the PCNA-binding domain of RFC has been functionally conserved during evolution. In addition, ATP hydrolysis was not required either for DNA polymerase stimulation or PCNA-loading in vitro.

  8. Heparin and Vascular Endothelial Growth Factor Loaded Poly(L-lactide-co-caprolactone) Nanofiber Covered Stent-Graft for Aneurysm Treatment.

    Science.gov (United States)

    Wang, Jing; An, Qingzhu; Li, Dawei; Wu, Tong; Chen, Weiming; Sun, Binbin; El-Hamshary, Hany; Al-Deyab, Salem S; Zhu, Wei; Mo, Xiumei

    2015-11-01

    Restenosis caused by thrombopoiesis is one of the biggest hinders of endovascular stent-graft used in small-diameter vessels. Rapid endothelialization of the lumen of stent is a promising approach to prevent thrombosis. In this study, we aimed at loading heparin, a potent anticoagulants, and vascular endothelial growth factor (VEGF) into the core of poly(L-lactide-co-caprolactone) nanofiber via emulsion electrospinning. The nanofiber was covered on the stent and applied in the treatment of vascular diseases such as aneurysm. The morphologies of the emulsion electrospun nanofibers and core--shell structure were observed by scanning electron microscope and laser scanning confocal microscope. The release profiles of heparin and VEGF, degradation rate of nanofiber mats and cell proliferation in vitro were investigated. It was found that the release of both heparin and VEGF from the nanofiber lasted for more than 30 days without serious initial burst release. The degradation rate of nanofiber mats containing heparin and VEGF was faster than that of pure PLCL nanofiber mats. Moreover, the released VEGF could promote the proliferation of Pig iliac endothelial cells (PIECs) cultured on the nanofiber mat, which was of great benefit to stent endothelialization. The results of digital subtraction angiography (DSA) follow-up indicated the aneurysm was obliterated by separating the aneurysm dome from the blood circulation and the parent artery kept long-term patency. Results of the study demonstrated that the heparin and VEGF loaded nanofiber could provide an approach to fabricate covered stent-graft with properties of anticoagulation and induction of rapid endothelialization.

  9. Strategies for improving performance in long duration events: Olympic distance triathlon.

    Science.gov (United States)

    Hausswirth, Christophe; Brisswalter, Jeanick

    2008-01-01

    This review focuses on strategic aspects that may affect performance in a long-duration Olympic event, the Olympic distance triathlon. Given the variety of races during the Olympic Games triathlon, strategic aspects include improving technological features as well as energetics factors affecting overall triathlon performance. During the last decade, many studies have attempted to identify factors reducing the metabolic load associated (or not) with the development of fatigue process by analysing the relationship between metabolic and biomechanical factors with exercise duration. To date, a consensus exists about the benefit of adopting a drafting position during the swimming or the cycling part of the triathlon. Other potential strategic factors, such as the production of power output or the selection of cadence during the cycling or the running leg, are likely to affect the overall triathlon performance. Within this approach, pacing strategies are observed by elite athletes who swim or cycle in a sheltered position, inducing several changes of pace, intensity or stochastic shifts in the amplitude of the physiological responses. The analysis of these parameters appears to arouse some experimental and practical interest from researchers and coachers, especially for long-distance Olympic events.

  10. The interface of mechanical loading and biological variables as they pertain to the development of tendinosis.

    Science.gov (United States)

    Thornton, G M; Hart, D A

    2011-06-01

    Different tendons are designed to withstand different mechanical loads in their individual environments. Variable physiologic loading ranges and correspondingly different injury thresholds lead to tendon heterogeneity. Also, tendon heterogeneity is evident when examining how different tendons regulate their response to changes in mechanical loading (over- and under-loading). The response of tendons to changes in mechanical loading plays an important role in the induction and progression of tendinosis which is tendon degeneration without inflammation. Tendon overuse injury is likely related to abnormal mechanical loading that deviates from normal mechanical loading in magnitude, frequency, duration and/or direction. Mechanical loading that results in tendon overuse injury can initiate a repair process but, after failed initial repair, non-resolving chronic attempted repair appears to lead to a "smoldering" fibrogenesis. Contributions of regulatory components, including minor components in the "nerve-mast cell-myofibroblast axis", are key features in the development and progression of tendinosis. Hormonal and genetic factors may also influence risk for tendinosis. Further understanding of how tendinosis induction is related to mechanical use/overuse, how tendinosis progression is related to abnormal regulation of attempted repair, and how induction and/or progression are modulated by other risk factors may lead to interventions that mitigate risk and enhance functional repair.

  11. Iron load

    Directory of Open Access Journals (Sweden)

    Filippo Cassarà

    2013-03-01

    Full Text Available Recent research addressed the main role of hepcidin in the regulation of iron metabolism. However, while this mechanism could be relevant in causing iron load in Thalassemia Intermedia and Sickle-Cell Anemia, its role in Thalassemia Major (TM is marginal. This is mainly due to the high impact of transfusional requirement into the severe increase of body iron. Moreover, the damage of iron load may be worsened by infections, as HCV hepatitis, or liver and endocrinological damage. One of the most relevant associations was found between splenectomy and increase of risk for mortality due,probably, to more severe iron load. These issues suggest as morbidity and mortality of this group of patients they do not depend only by our ability in controlling heart damage but even in preventing or treating particular infections and complications. This finding is supported by the impairment of survival curves in patients with complications different from heart damage. However, because, during recent years different direct and indirect methods to detect iron overload in patients affected by secondary hemochromatosis have been implemented, our ability to maintain under control iron load is significantly improved. Anyway, the future in iron load management remains to be able to have an iron load map of our body for targeting chelation and other medical treatment according to the single organ damage.

  12. 脑卒中患者居家照顾负荷因素分析%Load Factor Analysis of Home Caregivers of Stroke Patients

    Institute of Scientific and Technical Information of China (English)

    刘颖; 许慧荣; 马云洁

    2011-01-01

    Objective To know the current situation of load of hom e caregivers of stroke patients (including physical,psychological,socialand econom ic).T o discuss the influencing factor of hom e caregivers (such as the patient's degree of disability,the characteristics of caregivers,social support system s,etc.) M ethods Investigating 96 hom e caregivers of stroke patients from neurology clinic during A pril 2011 and June 2011 by questionnaire survey.R esults S troke patients need assistance in daily life accounted for 55.2%.C aregivers w ere under considerable pressure.T he m ain factors of caregiver's burden w ere course of disease,activities of daily living,caregiver's age,gender and care tim e per day.C onclusion H om e caregivers of Stroke Patients have load,they should be of concern.M ethods should be taken to im prove com m unity services,enhance the role of social support systems.%目的 通过了解脑卒中患者居家照顾者负荷的现状(包括生理、心理、社会和经济方面的负荷),探讨主要照顾者负荷的影响因素(如病人的残障程度、照顾者的特征、社会支持系统等).方法 以问卷调查的方式,抽样2011年4月-6月期间.在我院神经内科门诊复诊的脑卒中患者的居家主要照顾者96例.结果 脑卒中患者的日常生活能力需要协助者占55.2%,照顾者所承受的压力明显存在,社会支持系统不足.照顾者负荷的主要因素为患者病程、日常生活能力、照顾者年龄、性别和每日照顾时间等.结论 脑卒中患者居家主要照顾者存在压力性负荷,在关注患者的同时也应关注照顾者,完善社区服务,提高社会支持系统的作用.

  13. The association between periodontitis and sleep duration.

    Science.gov (United States)

    Romandini, Mario; Gioco, Gioele; Perfetti, Giorgio; Deli, Giorgio; Staderini, Edoardo; Laforì, Andreina

    2017-05-01

    Due to its potential to influence systemic inflammation and oxidative stress, and to predispose to bacterial infections, sleep duration could potentially be a risk factor for periodontitis. The aim of this cross-sectional study was to evaluate if there was in 2012 an association between periodontitis and sleep duration in a representative sample of the South Korean population. A total of 5812 subjects representative of 39.4 million of adults were examined. Multivariate logistic regressions were applied controlling for age, gender, education, smoking status, alcoholism and consumption frequency of coffee, tea, chocolate and red wine. Compared to the group sleeping ≤5 h/day, the adjusted odds ratios for periodontitis prevalence defined as Community Periodontal Index (CPI) = 4 were OR = 2.46 (95% CI: 1.20-5.06) in the 6 h/day sleepers group, OR = 2.66 (95% CI: 1.35-5.25) in the 7 h/day sleepers group, OR = 2.29 (95% CI: 1.13-4.63) in the 8 h/day sleepers group and OR = 4.27 (95% CI: 1.83-9.97) in the ≥9 h/day sleepers group. The association has shown to be highlighted in middle-aged people, females, non-smokers, lower educated, with lower lead and higher cadmium blood levels and with higher carotene dietary intake ones and to be partially mediated by lipid profile alterations, diabetes, serum Vitamin D levels and WBC count. A novel, direct and independent association between sleep duration and the prevalence of periodontitis was found. However, it needs to be investigated how the factors influencing the sleep duration affect this association. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Assessment and Methods for Supply-Following Loads in Modern Electricity Grids with Deep Renewables Penetration

    Science.gov (United States)

    2013-12-18

    Generation Type Capacity / Peak (GW ) Total Energy (%) Capacity/Load Factors (%) Renewables Geothermal 2.600 / 1.095 3.8% 38.7% / 92.0% Biomass/Biogas...fossil fuel needs can apply to other generation types as well. For example, geothermal , biomass, and biogas facilities all may have flexibility in... power plant , or flexible refrigerators could flatten duration curves of fossil fuel resources rather than the total demand on the grid, perhaps

  15. Biota Modeling in EPA's Preliminary Remediation Goal and Dose Compliance Concentration Calculators for Use in EPA Superfund Risk Assessment: Explanation of Intake Rate Derivation, Transfer Factor Compilation, and Mass Loading Factor Sources

    Energy Technology Data Exchange (ETDEWEB)

    Manning, Karessa L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dolislager, Fredrick G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bellamy, Michael B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-11-01

    The Preliminary Remediation Goal (PRG) and Dose Compliance Concentration (DCC) calculators are screening level tools that set forth Environmental Protection Agency's (EPA) recommended approaches, based upon currently available information with respect to risk assessment, for response actions at Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) sites, commonly known as Superfund. The screening levels derived by the PRG and DCC calculators are used to identify isotopes contributing the highest risk and dose as well as establish preliminary remediation goals. Each calculator has a residential gardening scenario and subsistence farmer exposure scenarios that require modeling of the transfer of contaminants from soil and water into various types of biota (crops and animal products). New publications of human intake rates of biota; farm animal intakes of water, soil, and fodder; and soil to plant interactions require updates be implemented into the PRG and DCC exposure scenarios. Recent improvements have been made in the biota modeling for these calculators, including newly derived biota intake rates, more comprehensive soil mass loading factors (MLFs), and more comprehensive soil to tissue transfer factors (TFs) for animals and soil to plant transfer factors (BV's). New biota have been added in both the produce and animal products categories that greatly improve the accuracy and utility of the PRG and DCC calculators and encompass greater geographic diversity on a national and international scale.

  16. Data on respiratory variables in critically ill patients with acute respiratory failure placed on proportional assist ventilation with load adjustable gain factors (PAV+).

    Science.gov (United States)

    Georgopoulos, Dimitris; Xirouchaki, Nectaria; Tzanakis, Nikolaos; Younes, Magdy

    2016-09-01

    The data show respiratory variables in 108 critically ill patients with acute respiratory failure placed on proportional assist ventilation with load adjustable gain factors (PAV+) after at least 36 h on passive mechanical ventilation. PAV+ was continued for 48 h until the patients met pre-defined criteria either for switching to controlled modes or for breathing without ventilator assistance. Data during passive mechanical ventilation and during PAV+ are reported. Data are acquired from the whole population, as well as from patients with and without acute respiratory distress syndrome. The reported variables are tidal volume, driving pressure (ΔP, the difference between static end-inspiratory plateau pressure and positive end-expiratory airway pressure), respiratory system compliance and resistance, and arterial blood gasses. The data are supplemental to our original research article, which described individual ΔP in these patients and examined how it related to ΔP when the same patients were ventilated with passive mechanical ventilation using the currently accepted lung-protective strategy "Driving pressure during assisted mechanical ventilation. Is it controlled by patient brain?" [1].

  17. Data on respiratory variables in critically ill patients with acute respiratory failure placed on proportional assist ventilation with load adjustable gain factors (PAV+

    Directory of Open Access Journals (Sweden)

    Dimitris Georgopoulos

    2016-09-01

    Full Text Available The data show respiratory variables in 108 critically ill patients with acute respiratory failure placed on proportional assist ventilation with load adjustable gain factors (PAV+ after at least 36 h on passive mechanical ventilation. PAV+ was continued for 48 h until the patients met pre-defined criteria either for switching to controlled modes or for breathing without ventilator assistance. Data during passive mechanical ventilation and during PAV+ are reported. Data are acquired from the whole population, as well as from patients with and without acute respiratory distress syndrome. The reported variables are tidal volume, driving pressure (ΔP, the difference between static end-inspiratory plateau pressure and positive end-expiratory airway pressure, respiratory system compliance and resistance, and arterial blood gasses. The data are supplemental to our original research article, which described individual ΔP in these patients and examined how it related to ΔP when the same patients were ventilated with passive mechanical ventilation using the currently accepted lung-protective strategy “Driving pressure during assisted mechanical ventilation. Is it controlled by patient brain?” [1].

  18. Unemployment duration and unemployment insurance

    DEFF Research Database (Denmark)

    Røed, Knut; Jensen, Peter; Thoursie, Anna

    2008-01-01

    Based on pooled register data from Norway and Sweden, we find that differences in unemployment duration patterns reflect dissimilarities in unemployment insurance (UI) systems in a way that convincingly establishes the link between economic incentives and job search behaviour. Specifically, UI...

  19. Extended duration orbiter (EDO) insignia

    Science.gov (United States)

    1990-01-01

    Extended duration orbiter (EDO) insignia incorporates a space shuttle orbiter with payload bay doors (PLBDs) open and a spacelab module inside. Trailing the orbiter are the initials EDO. The EDO-modified Columbia, Orbiter Vehicle (OV) 102, will be flown for the first EDO mission, STS-50.

  20. Short duration gamma ray bursts

    Indian Academy of Sciences (India)

    Patrick Das Gupta

    2004-10-01

    After a short review of gamma ray bursts (GRBs), we discuss the physical implications of strong statistical correlations seen among some of the parameters of short duration bursts (90 < 2 s). Finally, we conclude with a brief sketch of a new unified model for long and short GRBs.

  1. 高速公路路段交通量分析及轴载换算%Analysis of Traffic Volume and Equivalent Axle Load Factors in Freeway Sections

    Institute of Scientific and Technical Information of China (English)

    朱靓雯; 刘黎萍

    2016-01-01

    交通荷载数据对沥青路面设计和管理有重要作用。轴载谱方法可以更为全面、准确地描述交通荷载。文中收集了江西省部分高速公路荷载站点的实测轴载数据和交通量数据。通过对每一辆车进出收费站的名称识别,结合公路网分布统计得到各路段的交通荷载数据集合。对各路段实测轴载数据特征、交通增长率和累计标准轴次等进行分析,建立了轴载谱数据和交通量数据之间的关系,并给出了调查地区的当量轴次换算系数参考值。%Traffic loading data is very important for asphalt pavement design and management.Axle load spectrum is more comprehensive and accurate in describing the traffic load.This study collected the measured axle load data and traffic volume data of asphalt pavement freeways from toll gates in Jiangxi Province.Traffic loading data in freeway sections is obtained through the data from the en-trance and exit toll gate,combined with the highway network.The data was used to analyze the axle load spectrum factors,the number of accumulated equivalent axle loads,and the growth rate of equiv-alent axle loads.It has been found that the growth rate of equivalent axle loads in some highway sec-tions is negative.In addition,the relationship between axle load data and traffic volume data was de-veloped through the equivalent axle load factors,the value of which in investigated area was listed at last.

  2. Beam loading

    CERN Document Server

    Gamp, Alexander

    2013-01-01

    We begin by giving a description of the radio-frequency generator-cavity-beam coupled system in terms of basic quantities. Taking beam loading and cavity detuning into account, expressions for the cavity impedance as seen by the generator and as seen by the beam are derived. Subsequently methods of beam-loading compensation by cavity detuning, radio-frequency feedback and feedforward are described. Examples of digital radio-frequency phase and amplitude control for the special case of superconducting cavities are also given. Finally, a dedicated phase loop for damping synchrotron oscillations is discussed.

  3. Contribution to the investigation of the effective cyclic stress intensity factor in fatigue crack growth under cyclic load; Beitrag zur Untersuchung des effektiven zyklischen Spannungsintensitaetsfaktors bei Ermuedungsrisswachstum mit Belastungswechseln

    Energy Technology Data Exchange (ETDEWEB)

    Groening, T.

    2008-07-01

    Accurate component life forecasting under operating load necessitates an accurate crack propagation model which also takes account of serial effects resulting from cyclic loads. Crack growth can be described by means of the effective cyclic stress intensity factor independent of the external load. In experimental investigations, the cyclic stress intensity factor was defined for different single-stage loads, and the effective crack propagation curve was identified. On the basis of the curve of the effective stress intensity factor after a single overload, the resulting crack propagation rate can be predicted and can be used as a basis for a crack propagation model. With the aid of numeric investigations, the author also investigated the causes of the effective stress intensity factor; the intrinsic stresses were found to be the main cause. [German] Zur zuverlaessigen Lebensdauervorhersage von Bauteilen unter beliebiger Betriebsbelastung ist ein moeglichst gutes Rissfortschrittsmodell notwendig, welches auch Reihenfolgeeffekte durch Belastungswechsel beruecksichtigt. Das Risswachstum laesst sich dabei unabhaengig von der aeusseren Belastung mit Hilfe des effektiven zyklischen Spannungsintensitaetsfaktors beschreiben. In experimentellen Untersuchungen wird der effektive zyklische Spannungsintensitaetsfaktor fuer unterschiedliche einstufige Belastungen und die effektive Rissfortschrittskurve ermittelt. Durch den Verlauf des effektiven Spannungsintensitaetsfaktors nach einer einzelnen Ueberlast kann die resultierende Rissgeschwindigkeit vorausgesagt werden, was als Grundlage fuer ein Rissfortschrittsmodell ausgenutzt werden kann. Mit Hilfe numerischer Untersuchungen wird ausserdem die Ursache fuer den effektiven Spannungsintensitaetsfaktor betrachtet und die Eigenspannungen als hauptsaechliche Verursacher identifiziert.

  4. Sleep duration, cardiovascular disease, and proinflammatory biomarkers

    Directory of Open Access Journals (Sweden)

    Grandner MA

    2013-07-01

    molecules, including tumor necrosis factor-α, interleukins-1, -6, and -17, C-reactive protein, coagulation molecules, cellular adhesion molecules, and visfatin. Finally, a discussion of the limitations of current studies and future directions is provided. Keywords: sleep duration, inflammation, cardiovascular disease, cytokines

  5. Time interval between concussions and symptom duration.

    Science.gov (United States)

    Eisenberg, Matthew A; Andrea, John; Meehan, William; Mannix, Rebekah

    2013-07-01

    To test the hypothesis that children with a previous history of concussion have a longer duration of symptoms after a repeat concussion than those without such a history. Prospective cohort study of consecutive patients 11 to 22 years old presenting to the emergency department of a children's hospital with an acute concussion. The main outcome measure was time to symptom resolution, assessed by the Rivermead Post-Concussion Symptoms Questionnaire (RPSQ). Patients and providers completed a questionnaire describing mechanism of injury, associated symptoms, past medical history, examination findings, diagnostic studies, and the RPSQ. Patients were then serially administered the RPSQ for 3 months after the concussion or until all symptoms resolved. A total of 280 patients were enrolled over 12 months. Patients with a history of previous concussion had a longer duration of symptoms than those without previous concussion (24 vs 12 days, P = .02). Median symptom duration was even longer for patients with multiple previous concussions (28 days, P = .03) and for those who had sustained a concussion within the previous year (35 days, P = .007) compared with patients without those risk factors. In a multivariate model, previous concussion, absence of loss of consciousness, age ≥13, and initial RPSQ score >18 were significant predictors of prolonged recovery. Children with a history of a previous concussion, particularly recent or multiple concussions, are at increased risk for prolonged symptoms after concussion. These findings have direct implications on the management of patients with concussion who are at high risk for repeat injuries.

  6. Gambogic acid-loaded magnetic Fe3O4 nanoparticles inhibit Panc-1 pancreatic cancer cell proliferation and migration by inactivating transcription factor ETS1

    Directory of Open Access Journals (Sweden)

    Wang C

    2012-02-01

    Full Text Available Cailian Wang1, Haijun Zhang1, Yan Chen1, Fangfang Shi1, Baoan Chen2,31Department of Oncology, 2Department of Hematology, Zhongda Hospital, 3Faculty of Oncology, Medical School, Southeast University, Nanjing, People’s Republic of ChinaBackground: E26 transformation-specific sequence-1 (ETS1 transcription factor plays important roles in both carcinogenesis and the progression of a wide range of malignancies. Aberrant ETS1 expression correlates with aggressive tumor behavior and a poorer prognosis in patients with various malignancies. The aim of the current study was to evaluate the efficacy of a drug delivery system utilizing gambogic acid-loaded magnetic Fe3O4 nanoparticles (GA-MNP- Fe3O4 on the suppression of ETS1-mediated cell proliferation and migration in Panc-1 pancreatic cancer cells.Methods: The effects caused by GA-MNP- Fe3O4 on the proliferation of Panc-1 pancreatic cancer cells were evaluated using a MTT (3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide assay while inhibition of tumor cell migration was investigated in a scratch assay. The expressions of ETS1, cyclin D1, urokinase-type plasminogen activator (u-PA, and VEGF (vascular endothelial growth factor were examined by Western blot to elucidate the possible mechanisms involved.Results: In Panc-1 pancreatic cancer cells, we observed that application of GA-MNP- Fe3O4 was able to suppress cancer cell proliferation and prevent cells from migrating effectively. After treatment, Panc-1 pancreatic cancer cells showed significantly decreased expression of ETS1, as well as its downstream target genes for cyclin D1, u-PA, and VEGF.Conclusion: Our novel finding reaffirmed the significance of ETS1 in the treatment of pancreatic cancer, and application of GA-MNP- Fe3O4 nanoparticles targeting ETS1 should be considered as a promising contribution for better pancreatic cancer care.Keywords: ETS1 transcription factor, gambogic acid, pancreatic cancer, magnetic nanoparticles

  7. Carbohydrate Loading.

    Science.gov (United States)

    Csernus, Marilyn

    Carbohydrate loading is a frequently used technique to improve performance by altering an athlete's diet. The objective is to increase glycogen stored in muscles for use in prolonged strenuous exercise. For two to three days, the athlete consumes a diet that is low in carbohydrates and high in fat and protein while continuing to exercise and…

  8. Load sensor

    NARCIS (Netherlands)

    Van den Ende, D.; Almeida, P.M.R.; Dingemans, T.J.; Van der Zwaag, S.

    2007-01-01

    The invention relates to a load sensor comprising a polymer matrix and a piezo-ceramic material such as PZT, em not bedded in the polymer matrix, which together form a compos not ite, wherein the polymer matrix is a liquid crystalline resin, and wherein the piezo-ceramic material is a PZT powder for

  9. Carbohydrate Loading.

    Science.gov (United States)

    Csernus, Marilyn

    Carbohydrate loading is a frequently used technique to improve performance by altering an athlete's diet. The objective is to increase glycogen stored in muscles for use in prolonged strenuous exercise. For two to three days, the athlete consumes a diet that is low in carbohydrates and high in fat and protein while continuing to exercise and…

  10. Retrospective Analysis of Inflight Exercise Loading and Physiological Outcomes

    Science.gov (United States)

    Ploutz-Snyder, L. L.; Buxton, R. E.; De Witt, J. K.; Guilliams, M. E.; Hanson, A. M.; Peters, B. T.; Pandorf, M. M. Scott; Sibonga, J. D.

    2014-01-01

    Astronauts perform exercise throughout their missions to counter the health declines that occur as a result of long-term exposure to weightlessness. Although all astronauts perform exercise during their missions, the specific prescriptions, and thus the mechanical loading, differs among individuals. For example, inflight ground reaction force data indicate that subject-specific differences exist in foot forces created when exercising on the second-generation treadmill (T2) [1]. The current exercise devices allow astronauts to complete prescriptions at higher intensities, resulting in greater benefits with increased efficiency. Although physiological outcomes have improved, the specific factors related to the increased benefits are unknown. In-flight exercise hardware collect data that allows for exploratory analyses to determine if specific performance factors relate to physiological outcomes. These analyses are vital for understanding which components of exercise are most critical for optimal human health and performance. The relationship between exercise performance variables and physiological changes during flight has yet to be fully investigated. Identifying the critical performance variables that relate to improved physiological outcomes is vital for creating current and future exercise prescriptions to optimize astronaut health. The specific aims of this project are: 1) To quantify the exercise-related mechanical loading experienced by crewmembers on T2 and ARED during their mission on ISS; 2) To explore relationships between exercise loading variables, bone, and muscle health changes during the mission; 3) To determine if specific mechanical loading variables are more critical than others in protecting physiology; 4) To develop methodology for operational use in monitoring accumulated training loads during crew exercise programs. This retrospective analysis, which is currently in progress, is being conducted using data from astronauts that have flown long-duration

  11. Rent Control and Unemployment Duration

    DEFF Research Database (Denmark)

    Munch, Jacob R.; Rosholm, Michael; Svarer, Michael

    2005-01-01

    In this paper we analyse how rent control affects the duration of individual unemployment. In atheoretical search model we distinguish between two effects of rent control. On one hand, rentcontrol reduces housing mobility and hence mobility in the labour market. On the other hand, tomaintain rent...... control benefits, unemployed individuals are more likely to accept job offers in the local labour market. Based on a rich Danish data set, we find that the probability of finding a local job increases with the rent control intensity of the housing unit, whereas the probability of finding ajob outside...

  12. Unemployment duration and unemployment insurance

    DEFF Research Database (Denmark)

    Røed, Knut; Jensen, Peter; Thoursie, Anna

    2008-01-01

    Based on pooled register data from Norway and Sweden, we find that differences in unemployment duration patterns reflect dissimilarities in unemployment insurance (UI) systems in a way that convincingly establishes the link between economic incentives and job search behaviour. Specifically, UI...... benefits are relatively more generous for low-income workers in Sweden than in Norway, leading to relatively longer unemployment spells for low-income workers in Sweden. Based on the between-countries variation in replacement ratios, we find that the elasticity of the outflow rate from insured unemployment...

  13. Vowel duration issue in Civili

    OpenAIRE

    Ndinga-Koumba-Binza, Hugues Steve

    2009-01-01

    The main goal of this article is to define the problem of vowel duration in Civili (H12a). It shows that the so-called Civili vowel-length desperately needs to be re-examined, because previous works on the sound system of this language hardly explain a number of phonological phenomena, such as vowel lengthening, on the basis of data at hand. Demonstrating the problem in question, the author first reviews previous works that all identify a vowel lengthening in Civili. From different analyses t...

  14. Effect of walking speed on gait sub phase durations.

    Science.gov (United States)

    Hebenstreit, Felix; Leibold, Andreas; Krinner, Sebastian; Welsch, Götz; Lochmann, Matthias; Eskofier, Bjoern M

    2015-10-01

    Gait phase durations are important spatiotemporal parameters in different contexts such as discrimination between healthy and pathological gait and monitoring of treatment outcomes after interventions. Although gait phases strongly depend on walking speed, the influence of different speeds has rarely been investigated in literature. In this work, we examined the durations of the stance sub phases and the swing phase for 12 different walking speeds ranging from 0.6 to 1.7 m/s in 21 healthy subjects using infrared cinematography and an instrumented treadmill. We separated the stance phase into loading response, mid stance, terminal stance and pre-swing phase and we performed regression modeling of all phase durations with speed to determine general trends. With an increasing speed of 0.1m/s, stance duration decreased while swing duration increased by 0.3%. All distinct stance sub phases changed significantly with speed. These findings suggest the importance of including all distinct gait sub phases in spatiotemporal analyses, especially when different walking speeds are involved.

  15. Effect of Junction Temperature Swing Durations on a Lifetime of a Transfer Molded IGBT Module

    DEFF Research Database (Denmark)

    Choi, Uimin; Blaabjerg, Frede; Jorgensen, Soren

    2016-01-01

    In this paper, the effect of junction temperature swing duration on the lifetime of a transfer molded Intelligent Power IGBT Module is studied and a relevant lifetime factor is modeled. A temperature swing duration dependent lifetime factor is defined based on 38 accelerated power cycling test...... electrical conditions during the power cycling test. The analysis of the test results and the temperature swing duration dependent lifetime factor under different definitions and confidence levels are presented....

  16. FK506-loaded chitosan conduit promotes the regeneration of injured sciatic nerves in the rat through the upregulation of brain-derived neurotrophic factor and TrkB.

    Science.gov (United States)

    Zhao, Jia; Zheng, Xifu; Fu, Chongyang; Qu, Wei; Wei, Guoqiang; Zhang, Weiguo

    2014-09-15

    FK506 has been shown to exert neurotrophic and neuroprotective effects, but its long-term application for nerve regeneration is limited. This study evaluated the potential application of a novel FK506-loaded chitosan conduit for peripheral nerve repair, and explored the underlying mechanism. A sciatic nerve injury model was created in male Wistar rats, which were then randomly divided into three treatment groups (n=40, each): chitosan-only, chitosan+FK506 injection, and FK506-loaded chitosan. We found significant recovery of normal morphology of sciatic nerves and higher density of myelinated nerve fibers in rats treated with FK506-loaded chitosan. Similarly, the total number of myelinated nerve fibers, myelin sheath thickness, and axon diameters were significantly higher in this group compared with the others, and the compound muscle action potentials and motor nerve conduction velocity values of sciatic nerves were significantly higher. BDNF and TrkB levels in motor neurons were highest in rats treated with FK506-loaded chitosan. In conclusion, FK506-loaded chitosan promoted peripheral nerve repair and regeneration in a rat model of sciatic nerve injury. These effects are correlated with increased BDNF and TrkB expression in motor neurons.

  17. Effects of low glycaemic index/low glycaemic load vs. high glycaemic index/ high glycaemic load diets on overweight/obesity and associated risk factors in children and adolescents: a systematic review and meta-analysis.

    Science.gov (United States)

    Schwingshackl, Lukas; Hobl, Lisa Patricia; Hoffmann, Georg

    2015-08-25

    The objective of the present systematic review and meta-analysis was to synthesize the available literature data investigating the effects of low glycaemic index/low glycamic load dietary regimens on anthropometric parameters, blood lipid profiles, and indicators of glucose metabolism in children and adolescents. Literature search was performed using the electronic databases MEDLINE, EMBASE, and the Cochrane Central Register of trials with restrictions to randomized controlled trials, but no limitations concerning language and publication date. Parameters taken into account were: body weight, body mass index, z-score of body mass index, fat mass, fat-free mass, height, waist cicrumference, hip circumference, waist-to-hip ratio, total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, diastolic and systolic blood pressure, fasting serum glucose, fasting serum insulin, HOMA-index, glycosylated haemoglobin, and C-reactive protein. Meta-analyses were performed for each parameter to assess pooled effect in terms of weighted mean differences between the post-intervention (or differences in means) of the low glycaemic index diets and the respective high glycaemic index counterparts. Data analysis was performed using the Review Manager 5.3. software. Nine studies enrolling 1.065 children or adolescents met the inclusion criteria. Compared to diets providing a high gylcaemic index, low glycaemic index protocols resulted in significantly more pronounced decreases in serum triglycerides [mean differences -15.14 mg/dl, 95%-CI (-26.26, -4.00)] and HOMA-index [mean difference -0.70, 95%-CI (-1.37, -0.04), fixed-effects model only]. Other parameters under investigation were not affected by either low or high glycaemic indices. The present systematic review and meta-analysis provides evidence of a beneficial effect of a low glycaemic index/load diet in children and adolescents being either overweight or obese. Regarding the limitations of this analysis, further studies

  18. Neurocognition and Duration of Psychosis

    DEFF Research Database (Denmark)

    Rund, Bjørn Rishovd; Barder, Helene Eidsmo; Evensen, Julie

    2016-01-01

    A substantial proportion of schizophrenia-spectrum patients exhibit a cognitive impairment at illness onset. However, the long-term course of neurocognition and a possible neurotoxic effect of time spent in active psychosis, is a topic of controversy. Furthermore, it is of importance to find out...... what predicts the long-term course of neurocognition. Duration of untreated psychosis (DUP), accumulated time in psychosis the first year after start of treatment, relapse rates and symptoms are potential predictors of the long-term course. In this study, 261 first-episode psychosis patients were...... relationship between psychosis before (DUP) or after start of treatment and the composite score was found, providing no support for the neurotoxicity hypothesis, and indicating that psychosis before start of treatment has no significant impact on the course and outcome in psychosis. We found no association...

  19. Cohabitation Duration and Transient Domesticity.

    Science.gov (United States)

    Golub, Andrew; Reid, Megan; Strickler, Jennifer; Dunlap, Eloise

    2013-01-01

    Research finds that many impoverished urban Black adults engage in a pattern of partnering and family formation involving a succession of short cohabitations yielding children, a paradigm referred to as transient domesticity. Researchers have identified socioeconomic status, cultural adaptations, and urbanicity as explanations for aspects of this pattern. We used longitudinal data from the 2001 Survey of Income and Program Participation to analyze variation in cohabitation and marriage duration by race/ethnicity, income, and urban residence. Proportional hazards regression indicated that separation risk is greater among couples that are cohabiting, below 200% of the federal poverty line, and Black but is not greater among urban dwellers. This provides empirical demographic evidence to support the emerging theory of transient domesticity and suggests that both socioeconomic status and race explain this pattern. We discuss the implications of these findings for understanding transient domesticity and make recommendations for using the Survey of Income and Program Participation to further study this family formation paradigm.

  20. Fatores associados à duração dos benefícios por incapacidade: um estudo de coorte Factores asociados a la duración de los beneficios por incapacidad: un estudio de cohorte Factors associated with duration of disability benefits: a cohort study

    Directory of Open Access Journals (Sweden)

    Norma Suely Souto Souza

    2012-06-01

    identificados con técnicas de análisis de sobrevivencia. RESULTADOS: Posición socioeconómica baja (RR= 1,29; IC95% 1,02;1,64, edad por debajo de 39 años (RR= 1,23; IC95% 1,03;1,47, reposición de renta por el Instituto Nacional del Seguro Social OBJECTIVE: To analyze factors associated with the duration of disability benefits due to work-related upper-limb musculoskeletal disorders. METHODS: Ambispective cohort study conducted with 563 insured workers from the General Social Security System who received temporary disability benefits due to work-related upper-limb musculoskeletal disorders in the city of Salvador, Northeastern Brazil, in 2008. The data came from an inquiry performed by the Regional Audit of the National Social Security Institute and from administrative records. Sociodemographic and work-related variables were analyzed, as well as characteristics of the health problem and aspects related to social security. Factors associated with time until the cessation of the benefit were identified through survival analysis techniques. RESULTS: Low socioeconomic position (RR=1.29; 95% CI 1.02; 1.64, age below 39 years (RR=1.23; 95% CI 1.03; 1.47, income replacement by the National Social Security Institute < 100% (RR=1.24; 95% CI 1.04; 1.47 and high expectation of returning to work (RR=1.20; 95% CI 1.00; 1.44 are the categories related to higher rate of cessation of the benefit and with its shorter duration. CONCLUSIONS: Factors that are not strictly medical, like socioeconomic position, age, expectation of returning to work and level of income replacement by the National Social Security Institute, seem to influence the benefit's duration. These hypotheses need to be tested with further confirmatory studies in order to improve the understanding of the process of determining incapacity for work.

  1. A systematic review on immediate loading of implants used to support overdentures opposed by conventional prostheses : factors that might influence clinical outcomes

    NARCIS (Netherlands)

    Zygogiannis, K.; Wismeijer, D.; Aartman, I.H.A.; Osman, R.B.

    2016-01-01

    Purpose: Different treatment protocols in terms of number, diameter, and suprastructure design have been proposed for immediately loaded implants that are used to support mandibular overdentures opposed by maxillary conventional dentures. The aim of this study was to investigate the influence of

  2. 计及负荷率分档的峰谷分时电价定价模型%Pricing model of time-of-use electricity tariff considering customers classified by load factor

    Institute of Scientific and Technical Information of China (English)

    黄海涛; 吴洁晶; 顾丹珍; 蔚芳

    2016-01-01

    There is coordination problem between load factor price and peak-valley time-of-use price (TOU) of large and medium industrial and commercial users. Therefore, combining with the electricity power system and environment in China, this paper bases on the users demand and supply cost otherness to build the power consumption market segment and demand-price elastic model of load factor classification. Time-of-use electricity pricing model considering customers classified by load factor is settled applying the marginal cost pricing theory. The model adopts the method of hierarchical coordination optimization. The first layer applies the density clustering and two-part price theory to analyze the marginal electricity and capacity cost of each load factor block, and formulate the method for load factor classification and pricing average price for each one. The second layer takes the average price level of each block as constraint and cutting peak load to fill valley as the goal, then sets coordination optimization model of TOU tariff with load factor block based on the electric price elasticity matrix. This model coordinates multiple targets such as efficiency, fairness and peak load shifting. Its rationality and validity are validated by one case.%针对大中工商业用户负荷率电价与峰谷电价的配合问题,结合我国电力体制和电价制度环境,基于消费者需求和供电成本异质性,构造了负荷率分档用户的用电消费细分市场,建立了各档用户的边际供电成本模型及需求价格弹性模型。应用边际成本定价理论,构建了计及负荷率分档的峰谷分时电价模型。该模型采用分层协调优化的方法:第一层深入分析每一负荷率档位用户的边际电量成本和边际容量成本,应用密度聚类技术及两部制定价理论,建立了每一负荷率档位及其两部制平均电价水平的制定方法。第二层以各档平均电度电价水平为约束,以

  3. The role of the vascular endothelial growth factor/vascular endothelial growth factor receptors axis mediated angiogenesis in curcumin-loaded nanostructured lipid carriers induced human HepG2 cells apoptosis

    Directory of Open Access Journals (Sweden)

    Fengling Wang

    2015-01-01

    Full Text Available Background: Curcumin (diferuloylmethane, the active constituent of turmeric extract has potent anti-cancer properties have been demonstrated in hepatocellular carcinoma (HCC. However, its underlying molecular mechanism of therapeutic effects remains unclear. Vascular endothelial growth factor (VEGF and its receptors (VEGFRs have crucial roles in tumor angiogenesis. Purpose: The goal of this study was to investigate the role of the VEGF/VEGFRs mediated angiogenesis during the proliferation and apoptosis of human HepG2 hepatoma cell line and the effect of curcumin-loaded nanostructured lipid carriers (Cur-NLC. Materials and Methods: The proliferation of HepG2 cells was determined by methyl thiazolyl tetrazolium after exposure to Cur-NLC and native curcumin. Apoptosis was quantified by flow cytometry with annexin V-fluorescein isothiocyanate and propidium iodide staining. Cellular internalization of Cur-NLC was observed by fluorescent microscope. The level of VEGF was detected by enzyme-linked immunosorbent assay kits. The expression of VEGFRs was quantified by Western blotting. Results: Cur-NLC was more effective in inhibiting the proliferation and enhancing the apoptosis of HepG2 cells than native curcumin. Fluorescent microscope analysis showed that HepG2 cells internalized Cur-NLC more effectively than native curcumin. Furthermore, Cur-NLC down-regulated the level of VEGF and the expression of VEGFR-2, but had a slight effect on VEGFR-1. Conclusion: These results clearly demonstrated that Cur-NLC was more effective in anti-cancer activity than the free form of curcumin. These studies demonstrate for the 1 st time that Cur-NLC exerts an antitumor effect on HepG2 cells by modulating VEGF/VEGFRs signaling pathway.

  4. The effect of loading rate on pile bearing capacity of saturated sand

    NARCIS (Netherlands)

    Archeewa, E.

    2005-01-01

    Pile load tests are commonly used by engineers to determine its bearing capacity. At present, there are three methods of pile load tests: the static, the dynamic and the quasi-static test. The static pile load test is done by applying an axial load on the pile with a long duration. The dynamic and q

  5. The effect of loading rate on pile bearing capacity of saturated sand

    NARCIS (Netherlands)

    Archeewa, E.

    2005-01-01

    Pile load tests are commonly used by engineers to determine its bearing capacity. At present, there are three methods of pile load tests: the static, the dynamic and the quasi-static test. The static pile load test is done by applying an axial load on the pile with a long duration. The dynamic and q

  6. Combined impact of transient heat loads and steady-state plasma exposure on tungsten

    Energy Technology Data Exchange (ETDEWEB)

    Huber, Alexander, E-mail: A.Huber@fz-juelich.de [Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung, 52425 Jülich (Germany); Wirtz, Marius; Sergienko, Gennady; Steudel, Isabel [Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung, 52425 Jülich (Germany); Arakcheev, Aleksey; Burdakov, Aleksander [Budker Institute of Nuclear Physics (BINP), Novosibirsk 630090 (Russian Federation); Esser, Hans Guenter; Freisinger, Michaele; Kreter, Arkadi; Linke, Jochen; Linsmeier, Christian; Mertens, Philippe; Möller, Sören; Philipps, Volker; Pintsuk, Gerald; Reinhart, Michael; Schweer, Bernd [Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung, 52425 Jülich (Germany); Shoshin, Andrey [Budker Institute of Nuclear Physics (BINP), Novosibirsk 630090 (Russian Federation); Terra, Alexis; Unterberg, Bernhard [Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung, 52425 Jülich (Germany)

    2015-10-15

    Highlights: • W-samples under combined loading conditions show a lower damage threshold. • The pre-loaded W-samples show a lower damage threshold due to the D- embrittlement. • Pronounced increase of the D retention has been observed during the combined loads. • Enhanced blister formation has been observed under combined loading conditions. - Abstract: Cracking thresholds and crack patterns in tungsten targets have been studied in recent experiments after repetitive ITER-like ELM heat pulses in combination with plasma exposure in PSI-2 (Γ{sub target} = 2.5–4.0 × 10{sup 21} m{sup −2} s{sup −1}, ion energy on surface E{sub ion} = 60 eV, T{sub e} ≈ 10 eV). The heat pulses were simulated by laser irradiation. A Nd:YAG laser with energy per pulse of up to 32 J and a duration of 1 ms at the fundamental wavelength (λ = 1064 nm, repetition rate 0.5 Hz) was used to irradiate ITER-grade W samples with repetitive heat loads. In contrast to pure thermal exposure with a laser beam where the damage threshold under pure heat loads for ITER-grade W lies between 0.38 and 0.76 GW/m{sup 2}, the experiments with pre-loaded W-samples as well as under combined loading conditions show a lower damage threshold of 0.3 GW/m{sup 2}. This is probably due to deuterium embrittlement and/or a higher defect concentration in a region close to the surface due to supersaturation with deuterium. A pronounced increase in the D retention (more than a factor of five) has been observed during the combined transient heat loads and plasma exposure. Enhanced blister formation has been observed under these combined loading conditions.

  7. Load testing circuit

    DEFF Research Database (Denmark)

    2009-01-01

    A load testing circuit a circuit tests the load impedance of a load connected to an amplifier. The load impedance includes a first terminal and a second terminal, the load testing circuit comprising a signal generator providing a test signal of a defined bandwidth to the first terminal of the load...

  8. Association of sleep duration and insulin resistance in Taiwanese vegetarians

    Directory of Open Access Journals (Sweden)

    Chang Jiunn-Kae

    2012-08-01

    Full Text Available Abstract Background Short sleep duration has been reported to associate with increased insulin resistance. However, no studies have investigated whether such association exists in vegetarians. The aim of this study was to investigate the association between sleep duration and insulin resistance in Taiwanese vegetarians. Methods A total of 1290 individuals were recruited from a regional hospital in south Taiwan during their regular routine physical examination. Only individuals who described themselves as Buddhist vegetarians were included in the study. Demographic information and clinical characteristics were collected and multiple logistic regression analysis was used to evaluate the association between sleep duration and insulin resistance. Results A total of 433 vegetarians were included in the study. Results from univariate logistic regression indicated that insulin resistance was significantly associated with male sex, greater waist circumference, higher triglyceride levels, lower high-density lipoprotein cholesterol levels, higher plasma creatinine levels, higher alanine transaminase levels, greater energy expenditure, and sleep duration of more than 8 hours per night. Multiple logistic regression revealed that insulin resistance was significantly and independently associated with sleep duration of more than 8 hours per night (odd ratios = 2.27, 95% confidence interval = 1.24, 4.11 after adjusting for waist circumference and levels of alanine transaminase. Conclusions Sleep duration of more than 8 hours per night is an independent risk factor associated with increased insulin resistance in vegetarians.

  9. Association of sleep duration and insulin resistance in Taiwanese vegetarians.

    Science.gov (United States)

    Chang, Jiunn-Kae; Koo, Malcolm; Kao, Vivia Yu-Ying; Chiang, Jui-Kun

    2012-08-16

    Short sleep duration has been reported to associate with increased insulin resistance. However, no studies have investigated whether such association exists in vegetarians. The aim of this study was to investigate the association between sleep duration and insulin resistance in Taiwanese vegetarians. A total of 1290 individuals were recruited from a regional hospital in south Taiwan during their regular routine physical examination. Only individuals who described themselves as Buddhist vegetarians were included in the study. Demographic information and clinical characteristics were collected and multiple logistic regression analysis was used to evaluate the association between sleep duration and insulin resistance. A total of 433 vegetarians were included in the study. Results from univariate logistic regression indicated that insulin resistance was significantly associated with male sex, greater waist circumference, higher triglyceride levels, lower high-density lipoprotein cholesterol levels, higher plasma creatinine levels, higher alanine transaminase levels, greater energy expenditure, and sleep duration of more than 8 hours per night. Multiple logistic regression revealed that insulin resistance was significantly and independently associated with sleep duration of more than 8 hours per night (odd ratios = 2.27, 95% confidence interval = 1.24, 4.11) after adjusting for waist circumference and levels of alanine transaminase. Sleep duration of more than 8 hours per night is an independent risk factor associated with increased insulin resistance in vegetarians.

  10. The duration effect: a link between TTO and VAS values.

    Science.gov (United States)

    Craig, Benjamin M

    2009-02-01

    The value of a health state may depend on how long an individual has had to endure the health state (i.e. hedonic load). In this paper, we test the constant proportionality (CP) assumption and determine the sign of relationship between duration and health state value for 42 health states using the nationally representative data from the United Kingdom Measurement and Valuation of Health study. The results reject the CP assumption and suggest that the relationship is negative for optimal health (i.e. fair innings argument) and that the relationship is positive for poorer health states (i.e. adaptation). We find no evidence of the maximum endurable time hypothesis using these data. This evidence on the duration effect has important implications for outcomes research and the economic evaluation of interventions.

  11. Predicting physiological capacity of human load carriage - a review.

    Science.gov (United States)

    Drain, Jace; Billing, Daniel; Neesham-Smith, Daniel; Aisbett, Brad

    2016-01-01

    This review article aims to evaluate a proposed maximum acceptable work duration model for load carriage tasks. It is contended that this concept has particular relevance to physically demanding occupations such as military and firefighting. Personnel in these occupations are often required to perform very physically demanding tasks, over varying time periods, often involving load carriage. Previous research has investigated concepts related to physiological workload limits in occupational settings (e.g. industrial). Evidence suggests however, that existing (unloaded) workload guidelines are not appropriate for load carriage tasks. The utility of this model warrants further work to enable prediction of load carriage durations across a range of functional workloads for physically demanding occupations. If the maximum duration for which personnel can physiologically sustain a load carriage task could be accurately predicted, commanders and supervisors could better plan for and manage tasks to ensure operational imperatives were met whilst minimising health risks for their workers.

  12. Diffusion Indexes with Sparse Loadings

    DEFF Research Database (Denmark)

    Kristensen, Johannes Tang

    to the problem by using the LASSO as a variable selection method to choose between the possible variables and thus obtain sparse loadings from which factors or diffusion indexes can be formed. This allows us to build a more parsimonious factor model which is better suited for forecasting compared...

  13. Sleep Duration and Child Well-Being: A Nonlinear Association.

    Science.gov (United States)

    James, Sarah; Hale, Lauren

    2017-01-01

    Although numerous studies among adults have shown a U-shaped association between sleep duration and health outcomes, fewer studies have investigated the theory that children also have an optimal sleep duration range, with both lower and upper limits. We evaluated whether children's sleep duration at ages 5 and 9 has a U-shaped association with both behavioral problems and physical health at age 9. We analyzed data from 1,965 participants in a longitudinal birth cohort, the Fragile Families and Child Wellbeing Study. This sample of children was 52% male and approximately 22% non-Hispanic White, 52% non-Hispanic Black, 23% Hispanic, and 3% some other race/ethnicity. The child's primary caregiver reported the predictor of interest: sleep duration at age 5 and age 9. Both children and primary caregivers reported on outcomes of the child's behavior problems (internalizing and externalizing) and overall physical health. We found that the association between children's sleep duration and well-being was typically nonlinear and U-shaped. Adjusting for their sleep duration at age 5, children who sleep either too much or too little at age 9 had higher levels of behavior problems and scored lower on a global measure of physical health. These nonlinear patterns were similar whether children or primary caregivers reported child outcomes, with the exception that there was a linear and increasing association of longer sleep duration and caregiver-rated child health. This study highlights that both short and long sleep duration may be risk factors for adverse behavioral and health outcomes in school-age children.

  14. Intonation and Duration Curve in Persian Interrogative Sentences

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Keyhani

    2012-03-01

    Full Text Available Background and Aim: prosody is a very important factor in communication and includes such parameters as: duration, intonation, pitch, stress, rhythm etc. Intonation is the pitch variation in one sentence. Duration is the time taken to utter a voice. The aim of the present study was to evaluate some parameters of prosody such as duration and intonation curve in interrogative sentences among normal Farsi speaking adults in order to determine the characteristics of this aspect of language with an emphasis on laboratory testing.Methods: This study was performed as a cross-sectional one. The participants included 134 male and female Farsi speaking individuals aging between 18-30 years. In this study two interrogative sentences with open and closed answers were used. The voice samples were analyzed by Dr.speech -real analysis software. Data analysis incorporated unilateral analysis of variance and an intonation curve was drawn for each sentence.Results: The parameter of duration among men and women was significantly different (p≤0.001. Duration in open questions was significantly longer than yes/no questions (p≤0.001. The intonation curve of the two groups were similar.Conclusion: Men and women use duration changes, for making difference in prosody. On the whole, duration among women is longer than men. In open questions, the duration of sentences is mostly due to the question word. The intonation curve in open questions has more amplitude. Women show much more changes in basic frequency for transferring interrogative state in their expressions.

  15. Sleep Duration and Child Wellbeing: A Nonlinear Association

    Science.gov (United States)

    James, Sarah; Hale, Lauren

    2017-01-01

    Objective Although numerous studies among adults have shown a U-shaped association between sleep duration and health outcomes, fewer studies have investigated the theory that children also have an optimal sleep duration range, with both lower and upper limits. We evaluated whether children's sleep duration at ages 5 and 9 has a U-shaped association with both behavioral problems and physical health at age 9. Method We analyzed data from 1,965 participants in a longitudinal birth cohort, the Fragile Families and Child Wellbeing Study. This sample of children was 52% male and approximately 22% non-Hispanic white, 52% non-Hispanic black, 23% Hispanic, and 3% some other race/ethnicity. The child's primary caregiver reported the predictor of interest: sleep duration at age 5 and age 9. Both children and primary caregivers reported on outcomes of the child's behavior problems (internalizing and externalizing) and overall physical health. Results We found that the association between children's sleep duration and wellbeing was typically nonlinear and U-shaped. Adjusting for their sleep duration at age 5, children who sleep either too much or too little at age 9 had higher levels of behavior problems and scored lower on a global measure of physical health. These non-linear patterns were similar whether children or primary caregivers reported child outcomes, with the exception that there was a linear and increasing association of longer sleep duration and caregiver-rated child health. Conclusions This study highlights that both short and long sleep duration may be risk factors for adverse behavioral and health outcomes in school-aged children. PMID:27654036

  16. INCIDENCE AND UNEMPLOYMENT DURATION IN THE OLTENIA REGION

    OpenAIRE

    Daniela-Emanuela Dănăcică

    2011-01-01

    In this paper the author analyzes how identified factors influence the incidence and duration of unemployment spells in the Oltenia Region. The statistical data were obtained from the National Agency for Employment and the analyzed period is 1st January 2008-31st December 2010.

  17. INCIDENCE AND UNEMPLOYMENT DURATION IN THE OLTENIA REGION

    Directory of Open Access Journals (Sweden)

    Daniela-Emanuela Dănăcică

    2011-06-01

    Full Text Available In this paper the author analyzes how identified factors influence the incidence and duration of unemployment spells in the Oltenia Region. The statistical data were obtained from the National Agency for Employment and the analyzed period is 1st January 2008-31st December 2010.

  18. Fatores associados à duração do aleitamento materno em crianças menores de seis meses Factors associated with duration of breastfeeding in children under six months

    Directory of Open Access Journals (Sweden)

    Letícia Pacífico de Queiroz Salustiano

    2012-01-01

    Full Text Available OBJETIVO: Descrever as características maternas e das crianças, bem como avaliar os fatores associados à interrupção do aleitamento materno exclusivo. MÉTODOS: Estudo transversal que incluiu 667 crianças de seis meses que compareceram na Campanha de Multivacinação em Uberlândia, 2008. No delineamento amostral, foram sorteadas as unidades de vacinação e posteriormente as crianças em cada unidade, sistematicamente. Um instrumento semiestruturado foi utilizado para coleta dos dados, formulado com questões sobre alimentação da criança e características sociodemográficas da mãe. Foi utilizado risco relativo e teste do χ² para análise dos dados, aceitando como nível crítico pPURPOSE: To describe the characteristics of mothers and children and to evaluate the factors associated with discontinuation of exclusive breastfeeding. METHODS: A cross-sectional study on infants under six months of age who attended the vaccination campaign in 2008. In the sample design, vaccination units were selected by drawing lots and infants were similarly selected later at each unit systematically. A semi-structured instrument was used for data collection, containing questions about children's nutrition and socio-demographic characteristics. We used Odds Ratio and the χ² test for data analysis, accepting as the critical level p<0.05. RESULTS: The prevalence of breastfeeding for infants under 120 and 180 days of age was 89.5 and 85% respectively, and exclusive breastfeeding was 50.6 and 39.7% for infants less than 120 and 180 days of age, respectively. The factors most related to the abandonment of exclusive breastfeeding in infants under six months were maternal employment outside the home (OR=2.73; 95%CI=1.74-4.29 and use of pacifiers (OR=4.26; 95%CI=2.85-6.38. The mother being multiparous (OR=0.57; 95%CI=0.40-0.81 and receiving postpartum care in the public health care network (OR=0.55; 95%CI=0.39-0.79 represented protective factors against the

  19. Incident Duration Modeling Using Flexible Parametric Hazard-Based Models

    Directory of Open Access Journals (Sweden)

    Ruimin Li

    2014-01-01

    Full Text Available Assessing and prioritizing the duration time and effects of traffic incidents on major roads present significant challenges for road network managers. This study examines the effect of numerous factors associated with various types of incidents on their duration and proposes an incident duration prediction model. Several parametric accelerated failure time hazard-based models were examined, including Weibull, log-logistic, log-normal, and generalized gamma, as well as all models with gamma heterogeneity and flexible parametric hazard-based models with freedom ranging from one to ten, by analyzing a traffic incident dataset obtained from the Incident Reporting and Dispatching System in Beijing in 2008. Results show that different factors significantly affect different incident time phases, whose best distributions were diverse. Given the best hazard-based models of each incident time phase, the prediction result can be reasonable for most incidents. The results of this study can aid traffic incident management agencies not only in implementing strategies that would reduce incident duration, and thus reduce congestion, secondary incidents, and the associated human and economic losses, but also in effectively predicting incident duration time.

  20. Building a Shared Definitional Model of Long Duration Human Spaceflight

    Science.gov (United States)

    Orr, M.; Whitmire, A.; Sandoval, L.; Leveton, L.; Arias, D.

    2011-01-01

    In 1956, on the eve of human space travel Strughold first proposed a simple classification of the present and future stages of manned flight that identified key factors, risks and developmental stages for the evolutionary journey ahead. As we look to optimize the potential of the ISS as a gateway to new destinations, we need a current shared working definitional model of long duration human space flight to help guide our path. Initial search of formal and grey literature augmented by liaison with subject matter experts. Search strategy focused on both the use of term long duration mission and long duration spaceflight, and also broader related current and historical definitions and classification models of spaceflight. The related sea and air travel literature was also subsequently explored with a view to identifying analogous models or classification systems. There are multiple different definitions and classification systems for spaceflight including phase and type of mission, craft and payload and related risk management models. However the frequently used concepts of long duration mission and long duration spaceflight are infrequently operationally defined by authors, and no commonly referenced classical or gold standard definition or model of these terms emerged from the search. The categorization (Cat) system for sailing was found to be of potential analogous utility, with its focus on understanding the need for crew and craft autonomy at various levels of potential adversity and inability to gain outside support or return to a safe location, due to factors of time, distance and location.

  1. Incident duration modeling using flexible parametric hazard-based models.

    Science.gov (United States)

    Li, Ruimin; Shang, Pan

    2014-01-01

    Assessing and prioritizing the duration time and effects of traffic incidents on major roads present significant challenges for road network managers. This study examines the effect of numerous factors associated with various types of incidents on their duration and proposes an incident duration prediction model. Several parametric accelerated failure time hazard-based models were examined, including Weibull, log-logistic, log-normal, and generalized gamma, as well as all models with gamma heterogeneity and flexible parametric hazard-based models with freedom ranging from one to ten, by analyzing a traffic incident dataset obtained from the Incident Reporting and Dispatching System in Beijing in 2008. Results show that different factors significantly affect different incident time phases, whose best distributions were diverse. Given the best hazard-based models of each incident time phase, the prediction result can be reasonable for most incidents. The results of this study can aid traffic incident management agencies not only in implementing strategies that would reduce incident duration, and thus reduce congestion, secondary incidents, and the associated human and economic losses, but also in effectively predicting incident duration time.

  2. Effect of Junction Temperature Swing Durations on a Lifetime of a Transfer Molded IGBT Module

    DEFF Research Database (Denmark)

    Choi, Uimin; Blaabjerg, Frede; Jorgensen, Soren

    2016-01-01

    In this paper, the effect of junction temperature swing duration on the lifetime of a transfer molded Intelligent Power IGBT Module is studied and a relevant lifetime factor is modeled. A temperature swing duration dependent lifetime factor is defined based on 38 accelerated power cycling test...

  3. The contact mechanics and occurrence of edge loading in modular metal-on-polyethylene total hip replacement during daily activities.

    Science.gov (United States)

    Hua, Xijin; Li, Junyan; Jin, Zhongmin; Fisher, John

    2016-06-01

    The occurrence of edge loading in hip joint replacement has been associated with many factors such as prosthetic design, component malposition and activities of daily living. The present study aimed to quantify the occurrence of edge loading/contact at the articulating surface and to evaluate the effect of cup angles and edge loading on the contact mechanics of a modular metal-on-polyethylene (MoP) total hip replacement (THR) during different daily activities. A three-dimensional finite element model was developed based on a modular MoP bearing system. Different cup inclination and anteversion angles were modelled and six daily activities were considered. The results showed that edge loading was predicted during normal walking, ascending and descending stairs activities under steep cup inclination conditions (≥55°) while no edge loading was observed during standing up, sitting down and knee bending activities. The duration of edge loading increased with increased cup inclination angles and was affected by the cup anteversion angles. Edge loading caused elevated contact pressure at the articulating surface and substantially increased equivalent plastic strain of the polyethylene liner. The present study suggested that correct positioning the component to avoid edge loading that may occur during daily activities is important for MoP THR in clinical practice.

  4. Optimization of Load Recovery Scheme Considering System Security Factors%考虑系统安全因素的负荷恢复方案优化

    Institute of Scientific and Technical Information of China (English)

    刘文轩; 顾雪平; 王佳裕; 赵宝斌

    2016-01-01

    在电力系统网架重构初期,电网结构相对薄弱,恢复部分负荷可以在一定程度上维持系统功率平衡,确保系统安全运行。文中结合系统安全运行特征和负荷投入特点,建立相关负荷恢复模型,提出了一种考虑系统安全因素的负荷恢复方法;以网架各节点电压偏移程度、机组进相运行程度和潮流熵为目标函数,根据实际变电站负荷投入进行潮流调整,确定各节点负荷投入量,以满足系统功率平衡的要求;采用改进粒子群算法对恢复方案进行多目标优化,获得其Pareto 最优解集,并采用基于模糊反熵权的M-TOPSIS方法进行最优方案排序,以制订科学合理的负荷投入方案。最后,以新英格兰10机39节点系统和河北南网局部系统为算例验证了所述方法的有效性。%Load restoration in the early stage of network reconfiguration plays a role in maintaining power balance and stable operation of the power system. According to the operation characteristics of units and the pickup pattern of load, a corresponding model for load recovery is established.Moreover,a method for load pickup considering system stability is presented.The voltage deviation of the restored nodes,the leading phase operation situations of units and power flow entropy are defined as the obj ective functions.In order to obtain the optimal scheme,power flow regulation based on the load pickup patterns is carried out,and the amount of load pickup is determined.An improved particle swarm optimization algorithm is applied to search for the optimal scheme or feasible schemes.The Pareto optimal solution set acquired by solving the load recovery optimization model provides candidate schemes.The M-TOPSIS multiple attributes decision-making method based on fuzzy anti-entropy weight is applied to identify the satisfactory solution.In the end,effectiveness of the proposed method is validated by the optimization results on

  5. Special Considerations for Qualifying Thin Films for Supper Pressure Pumpkin Ultra Long Duration Balloon (ULDB) Missions

    Science.gov (United States)

    Said, M.

    Pumpkin type super pressure balloons require much less stringent mechanical requirements on the envelope film material when compared to spherical super pressure type balloons. However, since suitable thin films are typically viscoelastic in nature, their creep characteristics must be fully characterized and must not exceed specific and predetermined design limits. Proper assessment of materials limits to meet these design limits requires creep-load-temperature data that characterizes the performance of the material over a time that exceeds the duration of the design service life by some specified margin. Contrary to the behavior of materials with purely elastic response, visco-elastic materials such as these considered for the ULDB design, change their geometry under sustained loading over time. This change is usually reflected by exhibiting a significant visco-elastic component over the service life of the mission. For that regime of large visco-elastic response, where the material is highly nonlinear, a certain load-temperature threshold can be reached where the creep is limited by an asymptote that depends on both the temperature and load level. Such creep is recoverable, although the recovery period may be much longer than the 100 day design service life of the ULDB structure plus the factor of safety required for the design. For a typical flight, the most significant creep occurs at the highest temperature, which also produces the highest internal pressure. At mid- latitudes a significant portion of the service life is spent at night, i.e. at low temperature and low load; for the ULDB film, this nighttime contribution to creep is insignificant in comparison to any daytime contribution. By contrast, flight exposure in an Antarctic summer is at an almost constant high temperature and corresponding high pressure. This response behavior must be sufficiently characterized to serve the needs of the structural design and performance predictions of the vehicle in

  6. Optimal load shedding and restoration

    Science.gov (United States)

    Xu, Ding

    Load shedding is an emergency control action in power systems that can save systems from a wide-area blackout. Underfrequency load shedding, steady state load shedding, and voltage load shedding are widely used in power systems. These methods utilize either the steady state model or a simplified dynamic model to represent a power systems. In this dissertation, a general optimal load shedding method that considers both the dynamic process and load distribution is proposed. The unfavorable load shedding is then formulated as an optimization problem with the objective function of cost minimization. This objective function is subjected to system, security, and operation constraints. The entire problem becomes a question of optimization with differential and nonlinear equations as constraints. To solve this problem, discretization is used to change the differential equations into algebraic equations. The original problem is thus reformulated as an optimization problem and can be solved by a standard mathematical program. The general idea is then applied to traditional power systems, deregulated power systems, power systems with distributed generation, and load restoration. In the traditional power system, the method shows that governor action, generation dynamic, disturbance location, and economic factors can be taken into consideration. In the deregulated power system, two power market models are developed and incorporated into the load shedding scheme. In power systems with multiple distributed generations, the different cases of disturbances are analyzed and models of different distributed generation developed. The general idea is then applied. Finally, the load restoration problem is studied, and it is proposed that an optimization method be applied to it. This dissertation provides a comprehensive solution for load shedding problem in power systems. The models developed in this research can also be used to study other power system problems.

  7. Loads and loads and loads: The influence of prospective load, retrospective load, and ongoing task load in prospective memory

    Directory of Open Access Journals (Sweden)

    Beat eMeier

    2015-06-01

    Full Text Available In prospective memory tasks different kinds of load can occur. Adding a prospective memory task can impose a load on ongoing task performance. Adding ongoing task load can affect prospective memory performance. The existence of multiple target events increases prospective load and adding complexity to the to-be-remembered action increases retrospective load. In two experiments, we systematically examined the effects of these different types of load on prospective memory performance. Results showed an effect of prospective load on costs in the ongoing task for categorical targets (Experiment 2, but not for specific targets (Experiment 1. Retrospective load and ongoing task load both affected remembering the retrospective component of the prospective memory task. We suggest that prospective load can enhance costs in the ongoing task due to additional monitoring requirements. Retrospective load and ongoing task load seem to impact the division of resources between the ongoing task and retrieval of the retrospective component, which may affect disengagement from the ongoing task. In general, the results demonstrate that the different types of load affect prospective memory differentially.

  8. Jogging intensity and duration according to the students' index of physical condition.

    Directory of Open Access Journals (Sweden)

    Mykhaylov Vitalij Viktorovich

    2011-11-01

    Full Text Available A new method of heart rate defining and jogging duration is developed. It is based on the linear interconnection of the latter with the students' Index of Physical Condition. 27 students of 20-21 years old have taken part in the study. Their Index of Physical Condition is set using Cardi method (1.31÷2.76. Students are recommended to observe heart rate load 138÷148 beats per min in 30 min. jogging. The accuracy and the speed of physical workload defining (both heart rate load and jogging duration are improved using multiple linear regression.

  9. Smoking and health: association between telomere length and factors impacting on human disease, quality of life and life span in a large population-based cohort under the effect of smoking duration.

    Science.gov (United States)

    Babizhayev, Mark A; Yegorov, Yegor E

    2011-08-01

    Reactive oxygen species (ROS) are of primary importance as they cause damage to lipids, proteins, and DNA either endogenously by cellular mechanism, or through exogenous exposure to environmental injury factors, including oxidation insult factors, such as tobacco smoke. Currently 46.3 million adults (25.7 percent of the population) are smokers. This includes 24 million men (28.1 percent of the total) and more than 22 million women (23.5 percent). The prevalence is highest among persons 25-44 years of age. Cigarette smokers have a higher risk of developing several chronic disorders. These include fatty buildups in arteries, several types of cancer and chronic obstructive pulmonary disease (lung problems). As peripheral leukocytes have been the main target of human telomere research, most of what is known about human telomere dynamics in vivo is based on these cells. Leukocyte telomere length (TL) is a complex trait that is shaped by genetic, epigenetic, and environmental determinants. In this article, we consider that smoking modifies leukocyte TL in humans and contributes to its variability among individuals, although the smoking effect on TL and its relation with other metabolic indices may accelerate biological aging and development of smoking-induced chronic diseases in a large human population-based cohorts with smoking behavior. Recent studies confirmed that individuals with shorter telomeres present a higher prevalence of arterial lesions and higher risk of cardiovascular disease mortality. This study originally suggests that efficient therapeutic protection of TL and structure in response to stresses that are known to reduce TL, such as oxidative damage or inflammation associated with tobacco smoking, would lead to better telomere maintenance. Recently, we have discovered the potential use of telomere-restorative imidazole-containing dipeptide (non-hydrolized carnosine, carcinine) based therapy for better survival of smokers. We conclude that a better

  10. Effect of feeding duration and rumen fill on behaviour in dairy cows.

    Science.gov (United States)

    Lindström; Redbo

    2000-12-01

    The aim of the present experiment was to test the hypothesis that oral manipulation of feed is a behavioural need in cattle, irrespective of actual rumen load. Twelve rumen fistulated cows were used and subjected to four different treatments: low rumen content+long duration of eating (A), high rumen content+short duration of eating (B), high rumen content+long duration of eating (=positive control) (C) and low rumen content+short duration of eating (=negative control) (D). To obtain treatment A and B, rumen content was transferred by hand from cow A to B through the rumen fistulaes. Each treatment lasted for 3 days with 2 weeks of recovery between each new treatment. The experiment was repeated twice during two consecutive years. All cows were fed the same mixture of silage, concentrate and hay. The cows were videotaped under normal conditions (24h), and on the third day of the experiment. From these videotapes, the behaviours (frequency and duration per 24h) have been analysed.Time spent eating differed between the four treatments (Ptongue-rolling) was longer (Pcattle irrespective of rumen load. A low duration of feeding behaviours combined with a low rumen load, which is a common practice in certain categories of growing cattle or dry dairy cows, seriously impairs the welfare in cattle.

  11. Impaired sleep and allostatic load

    DEFF Research Database (Denmark)

    Clark, Alice Jessie; Dich, Nadya; Lange, Theis

    2014-01-01

    Objective: Understanding the mechanisms linking sleep impairment to morbidity and mortality is important for future prevention, but these mechanisms are far from elucidated. We aimed to determine the relation between impaired sleep, both in terms of duration and disturbed sleep, and allostatic load...... Biobank with comprehensive information on sleep duration, disturbed sleep, objective measures of an extensive range of biological risk markers, and physical conditions. Results: Long sleep (mean difference 0.23; 95% confidence interval, 0.13, 0.32) and disturbed sleep (0.14; 0.06, 0.22) were associated...... with higher AL as well as with high-risk levels of risk markers from the anthropometric, metabolic, and immune system. Sub-analyses suggested that the association between disturbed sleep and AL might be explained by underlying disorders. Whereas there was no association between short sleep and AL...

  12. Impaired sleep and allostatic load

    DEFF Research Database (Denmark)

    Clark, Alice Jessie; Dich, Nadya; Lange, Theis

    2014-01-01

    Objective: Understanding the mechanisms linking sleep impairment to morbidity and mortality is important for future prevention, but these mechanisms are far from elucidated. We aimed to determine the relation between impaired sleep, both in terms of duration and disturbed sleep, and allostatic load...... Biobank with comprehensive information on sleep duration, disturbed sleep, objective measures of an extensive range of biological risk markers, and physical conditions. Results: Long sleep (mean difference 0.23; 95% confidence interval, 0.13, 0.32) and disturbed sleep (0.14; 0.06, 0.22) were associated...... with higher AL as well as with high-risk levels of risk markers from the anthropometric, metabolic, and immune system. Sub-analyses suggested that the association between disturbed sleep and AL might be explained by underlying disorders. Whereas there was no association between short sleep and AL...

  13. The effect of predictability on subjective duration.

    Directory of Open Access Journals (Sweden)

    Vani Pariyadath

    Full Text Available Events can sometimes appear longer or shorter in duration than other events of equal length. For example, in a repeated presentation of auditory or visual stimuli, an unexpected object of equivalent duration appears to last longer. Illusions of duration distortion beg an important question of time representation: when durations dilate or contract, does time in general slow down or speed up during that moment? In other words, what entailments do duration distortions have with respect to other timing judgments? We here show that when a sound or visual flicker is presented in conjunction with an unexpected visual stimulus, neither the pitch of the sound nor the frequency of the flicker is affected by the apparent duration dilation. This demonstrates that subjective time in general is not slowed; instead, duration judgments can be manipulated with no concurrent impact on other temporal judgments. Like spatial vision, time perception appears to be underpinned by a collaboration of separate neural mechanisms that usually work in concert but are separable. We further show that the duration dilation of an unexpected stimulus is not enhanced by increasing its saliency, suggesting that the effect is more closely related to prediction violation than enhanced attention. Finally, duration distortions induced by violations of progressive number sequences implicate the involvement of high-level predictability, suggesting the involvement of areas higher than primary visual cortex. We suggest that duration distortions can be understood in terms of repetition suppression, in which neural responses to repeated stimuli are diminished.

  14. Some pollinators are more equal than others: Factors influencing pollen loads and seed set capacity of two actively and passively pollinating fig wasps

    Science.gov (United States)

    Kjellberg, Finn; Suleman, Nazia; Raja, Shazia; Tayou, Abelouahad; Hossaert-McKey, Martine; Compton, Stephen G.

    2014-05-01

    The nursery pollination system of fig trees (Ficus) results in the plants providing resources for pollinator fig wasp larvae as part of their male reproductive investment, with selection determining relative investment into pollinating wasps and the pollen they carry. The small size of Ficus pollen suggests that the quantities of pollen transported by individual wasps often limits male reproductive success. We assessed variation in fig wasp pollen loads and its influence on seed production in actively pollinated (Ficus montana) and passively pollinated (Ficus carica) dioecious fig trees.

  15. 艾滋病患者外周血病毒载量检出的影响因素分析%Analysis of Influencing Factors of Detection of Peripheral Blood Viral Load in AIDS Patients

    Institute of Scientific and Technical Information of China (English)

    刘会娟; 张肖肖; 蒋自强

    2012-01-01

    目的 从临床角度探讨艾滋病患者外周血病毒载量检出的影响因素,为临床治疗提供依据.方法 收集2010年以来我们中心开展的课题资料的人口学信息、实验室血常规、免疫学指标(CD+4T细胞计数、CD+8T细胞计数)及病毒载量检测值,影响因素分析采用Logistic回归.结果 纳入分析146例资料,其中89例外周血病毒载量<40 copys/ml(未检出组),57例外周血病毒载量≥40 copys/ml(检出组).Logistic回归分析最终纳入3个影响病毒载量是否检测出的主要因素,分别为较低年龄分段(<30岁,OR=15.875,P=0.001;30~39岁,OR=6.317,P=0.002;40~49岁,OR=2.387,P=0.129)、确认年限(OR=2.251,P=0.038)和CD+4T细胞计数分段(OR=0.382,P=0.014).结论 艾滋病患者外周血病毒载量是否检出的影响因素有确认时间、年龄分段和CD+4T细胞计数.%Objective To explore the factors influencing detection of peripheral blood viral load to provide a basis for its clinical treatment. Methods Demographic information, laboratory routine blood, immunological indexes ( CD/ T cell count, CD8+ T cell count ) and viral load assessment were collected from the subject data of AIDS Treatment and Research Center. Logistic regression analysis was carried out on influencing factors on level of viral load. Results A total of 146 cases were chosen for analysis, including 89 with a peripheral blood viral load <40 copys/ml ( un -detection group ) and 57 with load ≥40 copys/ml ( detection group ). Logistic regression analysis finally enrolled 3 main factors influencing viral load detection, including lower age segmentation ( <30yearsold, OR = 15.875, P=0.001; 30 ~ 39 years old, OR=6.317, P=0.002; 39-49 years old, OR=2.387, P=0.129), time confirmation ( OR = 2. 251, P = 0. 038 ) and CD4+ T cell count ( OR = 0. 382, P=0.014). Conclusion The factors influencing detection of peripheral blood viral load are time conformation, age segments and CD/ T cell count.

  16. Reliability-Based Load and Resistance Factors Design for Offshore Jacket Platforms in the Bohai Bay:Calibration on Target Reliability Index

    Institute of Scientific and Technical Information of China (English)

    JIN Wei-liang; HU Qi-zhong; SHEN Zhao-wei; SHI Zhong-min

    2009-01-01

    The target reliability index has been effectively used as the best solution to deal with the relationship between the structural safety and the optimal economy in any structural design.However,the target reliability index for offshore jacket platforms based on different sea areas in China has never been calibrated.This paper presents an approach for its calibration,and suggests many kinds of associated load cases.The uncertainties of loads and structural resistance are mainly investigated.The target reliability index for structural components,tubular joints and piles of offshore jacket platforms are discussed respectively in detail.Finally,through the calibrated results from the offshore jacket platforms of QK18-1,JZ20-2,SZ36-1 and BZ28-1 in the Bohai Bay,it is proposed to adopt 2.8 as the target reliability index of offshore jacket platforms in the Bohai Bay for a 25-year design period.The results provide significant reference for the design of offshore jacket platforms.

  17. Fitness Load and Exercise Time in Secondary Physical Education Classes.

    Science.gov (United States)

    Li, Xiao Jun; Dunham, Paul, Jr.

    1993-01-01

    Investigates the effect of secondary school physical education on fitness load: the product of the mean heart rate above threshold (144 bpm) and the time duration of heart rate above that threshold. Highly and moderately skilled students achieved fitness load more frequently than their lower skilled colleagues. (GLR)

  18. Electrical load detection aparatus

    DEFF Research Database (Denmark)

    2010-01-01

    A load detection technique for a load comprising multiple frequency-dependant sub-loads comprises measuring a representation of the impedance characteristic of the load; providing stored representations of a multiplicity of impedance characteristics of the load; each one of the stored representat...

  19. Road transport of farm animals: effects of journey duration on animal welfare

    DEFF Research Database (Denmark)

    Nielsen, Birte Lindstrøm; Dybkjær, Lise; Herskin, Mette S

    2011-01-01

    Transport of farm animals gives rise to concern about their welfare. Specific attention has been given to the duration of animal transport, and maximum journey durations are used in legislation that seek to minimise any negative impact of transport on animal welfare. This paper reviews......, and those aspects that may be exacerbated by journey time. We identify four aspects of animal transport, which have increasing impact on welfare as transport duration increases. These relate to (i) the physiological and clinical state of the animal before transport; and - during transport - to (ii) feeding...... the relatively few scientific investigations into effects of transport duration on animal welfare in cattle, sheep, horses, pigs and poultry. From the available literature, we attempt to distinguish between aspects, which will impair welfare on journeys of any duration, such as those associated with loading...

  20. Incorporating Duration Information in Activity Recognition

    Science.gov (United States)

    Chaurasia, Priyanka; Scotney, Bryan; McClean, Sally; Zhang, Shuai; Nugent, Chris

    Activity recognition has become a key issue in smart home environments. The problem involves learning high level activities from low level sensor data. Activity recognition can depend on several variables; one such variable is duration of engagement with sensorised items or duration of intervals between sensor activations that can provide useful information about personal behaviour. In this paper a probabilistic learning algorithm is proposed that incorporates episode, time and duration information to determine inhabitant identity and the activity being undertaken from low level sensor data. Our results verify that incorporating duration information consistently improves the accuracy.

  1. 5 CFR 330.1102 - Duration.

    Science.gov (United States)

    2010-01-01

    ... PLACEMENT (GENERAL) Federal Employment Priority Consideration Program for Displaced Employees of the District of Columbia Department of Corrections § 330.1102 Duration. This program terminates 1 year...

  2. Fade durations in satellite-path mobile radio propagation

    Science.gov (United States)

    Schmier, Robert G.; Bostian, Charles W.

    1986-01-01

    Fades on satellite to land mobile radio links are caused by several factors, the most important of which are multipath propagation and vegetative shadowing. Designers of vehicular satellite communications systems require information about the statistics of fade durations in order to overcome or compensate for the fades. Except for a few limiting cases, only the mean fade duration can be determined analytically, and all other statistics must be obtained experimentally or via simulation. This report describes and presents results from a computer program developed at Virginia Tech to simulate satellite path propagation of a mobile station in a rural area. It generates rapidly-fading and slowly-fading signals by separate processes that yield correct cumulative signal distributions and then combines these to simulate the overall signal. This is then analyzed to yield the statistics of fade duration.

  3. Mitochondrial DNA Copy Number in Sleep Duration Discordant Monozygotic Twins

    DEFF Research Database (Denmark)

    Wrede, Joanna E; Mengel-From, Jonas; Buchwald, Dedra

    2015-01-01

    STUDY OBJECTIVES: Mitochondrial DNA (mtDNA) copy number is an important component of mitochondrial function and varies with age, disease, and environmental factors. We aimed to determine whether mtDNA copy number varies with habitual differences in sleep duration within pairs of monozygotic twins....... SETTING: Academic clinical research center. PARTICIPANTS: 15 sleep duration discordant monozygotic twin pairs (30 twins, 80% female; mean age 42.1 years [SD 15.0]). DESIGN: Sleep duration was phenotyped with wrist actigraphy. Each twin pair included a "normal" (7-9 h/24) and "short" (sleeping...... twin. Fasting peripheral blood leukocyte DNA was assessed for mtDNA copy number via the n-fold difference between qPCR measured mtDNA and nuclear DNA creating an mtDNA measure without absolute units. We used generalized estimating equation linear regression models accounting for the correlated data...

  4. Genetic Associations with Gestational Duration and Spontaneous Preterm Birth

    DEFF Research Database (Denmark)

    Zhang, Ge; Feenstra, Bjarke; Bacelis, Jonas

    2017-01-01

    Background Despite evidence that genetic factors contribute to the duration of gestation and the risk of preterm birth, robust associations with genetic variants have not been identified. We used large data sets that included the gestational duration to determine possible genetic associations....... Methods We performed a genomewide association study in a discovery set of samples obtained from 43,568 women of European ancestry using gestational duration as a continuous trait and term or preterm (birth as a dichotomous outcome. We used samples from three Nordic data sets (involving a total...... of association in the replication sets; these variants also showed genomewide significance in a joint analysis. Common variants in EBF1, EEFSEC, and AGTR2 showed association with preterm birth with genomewide significance. An analysis of mother-infant dyads suggested that these variants act at the level...

  5. FIXED TEMPORAL PATTERNS IN CHILDREN'S SPEECH DESPITE VARIABLE VOWEL DURATIONS.

    Science.gov (United States)

    Redford, Melissa A; Oh, Grace E

    2015-08-01

    The current study compared children's and adults' ability to produce inherent and context-specific vowel duration differences with their ability to repeatedly produce the same vowel in the same context. Children (5- and 8-year-olds) and adults produced real English words in a frame sentence multiple times. Mean vowel duration and variability in vowel duration were analysed as a function of the manipulated factors. Results were that children produced exactly the same contrasts as adults despite also exhibiting more variability in their production of individual vowels. The results are consistent with a model where the 'plan' is remembered relative timing information and execution is the achievement of motor goals at specified temporal intervals.

  6. Objective Sleep Duration Is Prospectively Associated With Endothelial Health.

    Science.gov (United States)

    Hall, Martica H; Mulukutla, Suresh; Kline, Christopher E; Samuelsson, Laura B; Taylor, Briana J; Thayer, Julian F; Krafty, Robert T; Frank, Ellen; Kupfer, David J

    2017-01-01

    The mechanisms linking short sleep duration to cardiovascular disease (CVD) are poorly understood. Emerging evidence suggests that endothelial dysregulation may lie along the causal pathway linking sleep duration to cardiovascular risk, although current evidence in humans is based on cross-sectional studies. Our objective was to evaluate the prospective association between objectively assessed sleep duration and clinical indices of endothelial health. A total of 141 medically healthy adults underwent an overnight laboratory sleep study when they were between the ages of 21 and 60 years. Total sleep time was objectively assessed by polysomnography at study entry. Endothelial health, including brachial artery diameter (BAD) and flow-mediated dilation (FMD), was measured 18.9 ± 4.6 years later. Medical health and psychiatric status were assessed at both time points. Approximately half of the sample had a lifetime history of major depressive disorder. In univariate analyses, shorter sleep duration was associated with increased BAD (β = -0.24, p = .004) and decreased FMD (β = 0.17, p = .042). BAD, but not FMD, remained significantly associated with sleep duration after adjusting for sex, age, body mass index (BMI), smoking, diabetes, hypertension, and lifetime history of major depressive disorder (MDD) at T2. The association between sleep duration and BAD was stronger than the association between BAD and an aggregate measure of CVD risk including three or more of the following risk factors: male sex, age ≥ 65 years, smoker, BMI ≥ 30, diabetes, hypertension, and MDD. Objectively assessed short sleep duration was prospectively associated with increased BAD over a 12- to 30-year period.

  7. Acute effects of cannabis on breath-holding duration.

    Science.gov (United States)

    Farris, Samantha G; Metrik, Jane

    2016-08-01

    Distress intolerance (an individual's perceived or actual inability to tolerate distressing psychological or physiological states) is associated with cannabis use. It is unknown whether a biobehavioral index of distress intolerance, breath-holding duration, is acutely influenced (increased or decreased) by cannabis. Such information may further inform understanding of the expression of psychological or physiological distress postcannabis use. This within-subjects study examined whether smoked marijuana with 2.7%-3.0% delta-9-tetrahydrocannabinol (THC), relative to placebo, acutely changed duration of breath holding. Participants (n = 88; 65.9% male) were nontreatment-seeking frequent cannabis users who smoked placebo or active THC cigarette on two separate study days and completed a breath-holding task postsmoking. Controlling for baseline breath-holding duration and participant sex, THC produced significantly shorter breath-holding durations relative to placebo. There was a significant interaction of drug administration × frequency of cannabis use, such that THC decreased breath-holding time among less frequent but not among more frequent users. Findings indicate that cannabis may exacerbate distress intolerance (via shorter breath-holding durations). As compared to less frequent cannabis users, frequent users display tolerance to cannabis' acute effects including increased ability to tolerate respiratory distress when holding breath. Objective measures of distress intolerance are sensitive to contextual factors such as acute drug intoxication, and may inform the link between cannabis use and the expression of psychological distress. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  8. Fault-tolerant scheduling algorithm with the load factor in Cyber-Physical Systems heterogeneous distributed real-time systems%CPS异构分布实时系统中带负载因子的容错调度

    Institute of Scientific and Technical Information of China (English)

    符利华; 张立臣

    2011-01-01

    This paper introduced the newest issue-Cyber-Physical Systems (CPS) and some basic contents of Cyber-Physical Systems. And then,it gave a heterogeneous distributed real-time task system model in the Cyber-Physical Systems. Based on this model and the primary-backup technology ,this paper proposed two fault-tolerant scheduling algorithms,which adapt to the heterogeneous distributed real-time environment of Cyber-Physical Systems:HDLMA (Heterogeneous Distributed Min Loading Algorithm) and H DLFA (Heterogeneous Distributed Loading Factor Algorithm). Finally,this paper analyzed their schedulability,load balancing,the influence of the granularity of tasks on load balancing as well as how scheduling threshold affects the schedulability.%介绍了Cyber-Physical Systems的基本内容,给出了基于Cyber-Physical Systems异构分布式中的实时任务系统模型.并在该模型下结合基/副版本备份技术提出了两种适应于Cyber-Physical Systems异构分布式实时环境的启发式容错调度算法:HDLMA算法和HDLFA算法.最后针对这两种算法,分析了算法可调度性,负载均衡性,任务粒度大小对负载均衡性的影响,以及调度闽值对算法可调度性的影响.

  9. Distribution load estimation (DLE)

    Energy Technology Data Exchange (ETDEWEB)

    Seppaelae, A.; Lehtonen, M. [VTT Energy, Espoo (Finland)

    1998-08-01

    The load research has produced customer class load models to convert the customers` annual energy consumption to hourly load values. The reliability of load models applied from a nation-wide sample is limited in any specific network because many local circumstances are different from utility to utility and time to time. Therefore there is a need to find improvements to the load models or, in general, improvements to the load estimates. In Distribution Load Estimation (DLE) the measurements from the network are utilized to improve the customer class load models. The results of DLE will be new load models that better correspond to the loading of the distribution network but are still close to the original load models obtained by load research. The principal data flow of DLE is presented

  10. A combined M5P tree and hazard-based duration model for predicting urban freeway traffic accident durations.

    Science.gov (United States)

    Lin, Lei; Wang, Qian; Sadek, Adel W

    2016-06-01

    The duration of freeway traffic accidents duration is an important factor, which affects traffic congestion, environmental pollution, and secondary accidents. Among previous studies, the M5P algorithm has been shown to be an effective tool for predicting incident duration. M5P builds a tree-based model, like the traditional classification and regression tree (CART) method, but with multiple linear regression models as its leaves. The problem with M5P for accident duration prediction, however, is that whereas linear regression assumes that the conditional distribution of accident durations is normally distributed, the distribution for a "time-to-an-event" is almost certainly nonsymmetrical. A hazard-based duration model (HBDM) is a better choice for this kind of a "time-to-event" modeling scenario, and given this, HBDMs have been previously applied to analyze and predict traffic accidents duration. Previous research, however, has not yet applied HBDMs for accident duration prediction, in association with clustering or classification of the dataset to minimize data heterogeneity. The current paper proposes a novel approach for accident duration prediction, which improves on the original M5P tree algorithm through the construction of a M5P-HBDM model, in which the leaves of the M5P tree model are HBDMs instead of linear regression models. Such a model offers the advantage of minimizing data heterogeneity through dataset classification, and avoids the need for the incorrect assumption of normality for traffic accident durations. The proposed model was then tested on two freeway accident datasets. For each dataset, the first 500 records were used to train the following three models: (1) an M5P tree; (2) a HBDM; and (3) the proposed M5P-HBDM, and the remainder of data were used for testing. The results show that the proposed M5P-HBDM managed to identify more significant and meaningful variables than either M5P or HBDMs. Moreover, the M5P-HBDM had the lowest overall mean

  11. Nanoparticulate mineralized collagen scaffolds induce in vivo bone regeneration independent of progenitor cell loading or exogenous growth factor stimulation.

    Science.gov (United States)

    Ren, Xiaoyan; Tu, Victor; Bischoff, David; Weisgerber, Daniel W; Lewis, Michael S; Yamaguchi, Dean T; Miller, Timothy A; Harley, Brendan A C; Lee, Justine C

    2016-05-01

    Current strategies for skeletal regeneration often require co-delivery of scaffold technologies, growth factors, and cellular material. However, isolation and expansion of stem cells can be time consuming, costly, and requires an additional procedure for harvest. Further, the introduction of supraphysiologic doses of growth factors may result in untoward clinical side effects, warranting pursuit of alternative methods for stimulating osteogenesis. In this work, we describe a nanoparticulate mineralized collagen glycosaminoglycan scaffold that induces healing of critical-sized rabbit cranial defects without addition of expanded stem cells or exogenous growth factors. We demonstrate that the mechanism of osteogenic induction corresponds to an increase in canonical BMP receptor signalling secondary to autogenous production of BMP-2 and -9 early and BMP-4 later during differentiation. Thus, nanoparticulate mineralized collagen glycosaminoglycan scaffolds may provide a novel growth factor-free and ex vivo progenitor cell culture-free implantable method for bone regeneration.

  12. Valsalva maneuver: shortest optimal expiratory strain duration

    Directory of Open Access Journals (Sweden)

    Ramesh K. Khurana, Md

    2011-07-01

    Full Text Available Purpose : To quantitate the level of difficulty and determine consistency of hemodynamic responses with various expiratory strain (ES durations. Methods : Thirty-four healthy subjects performed the Valsalva maneuver (VM with an ES duration of 10, 12, and 15 seconds in random order. Level of difficulty after each trial was rated 1 to 10, with 10 being the most difficult. Blood pressure and heart rate (HR were recorded continuously and non-invasively. Parameters studied were Valsalva ratio (VR, early phase II (IIE, late phase II (IIL, tachycardia latency (TL, bradycardia latency (BL, and overshoot latency (OV-L. Consistency of responses was calculated. Results : Difficulty increased significantly with increased ES duration: 5.1±0.1 (mean±SEM at 10 seconds, 5.9±0.1 at 12 seconds, and 6.8±0.1 at 15 seconds (p<0.001. Phase IIE, TL, BL, OV-L, and VR response did not differ statistically with increasing ES durations, and there were no differences in variability. Phase IIL response increased significantly with increasing ES duration. Phase IIL was poorly delineated in 14 of 102 trials with 10 seconds ES duration. Conclusions : ES duration of 10 seconds created a low level of difficulty in healthy individuals. This strain duration produced consistent hemodynamic response for all parameters tested except IIL phase. The absence of IIL phase with 10 seconds ES should not be interpreted as an indicator of sympathetic vasoconstrictor failure.

  13. Wage effects of unemployment duration and frequency

    NARCIS (Netherlands)

    van Dijk, J.; Folmer, H

    This paper analyzes the wage effects of unemployment duration and frequency for different regional labor market situations in The Netherlands using a simultaneous equations approach. The main finding is that unemployment duration has a significant negative effect and the frequency of unemployment a

  14. Word Durations in Non-Native English

    Science.gov (United States)

    Baker, Rachel E.; Baese-Berk, Melissa; Bonnasse-Gahot, Laurent; Kim, Midam; Van Engen, Kristin J.; Bradlow, Ann R.

    2010-01-01

    In this study, we compare the effects of English lexical features on word duration for native and non-native English speakers and for non-native speakers with different L1s and a range of L2 experience. We also examine whether non-native word durations lead to judgments of a stronger foreign accent. We measured word durations in English paragraphs read by 12 American English (AE), 20 Korean, and 20 Chinese speakers. We also had AE listeners rate the `accentedness' of these non-native speakers. AE speech had shorter durations, greater within-speaker word duration variance, greater reduction of function words, and less between-speaker variance than non-native speech. However, both AE and non-native speakers showed sensitivity to lexical predictability by reducing second mentions and high frequency words. Non-native speakers with more native-like word durations, greater within-speaker word duration variance, and greater function word reduction were perceived as less accented. Overall, these findings identify word duration as an important and complex feature of foreign-accented English. PMID:21516172

  15. Wind Loads on Structures

    DEFF Research Database (Denmark)

    Dyrbye, Claes; Hansen, Svend Ole

    pressure to structural response) and design criteria. Starting with an introduction of the wind load chain, the book moves on to meteorological considerations, atmospheric boundary layer, static wind load, dynamic wind load and scaling laws used in wind-tunnel tests. The dynamic wind load covers vibrations......Wind loads have to be taken into account when designing civil engineering structures. The wind load on structures can be systematised by means of the wind load chain: wind climate (global), terrain (wind at low height), aerodynamic response (wind load to pressure), mechanical response (wind...

  16. Distribution load estimation - DLE

    Energy Technology Data Exchange (ETDEWEB)

    Seppaelae, A. [VTT Energy, Espoo (Finland)

    1996-12-31

    The load research project has produced statistical information in the form of load models to convert the figures of annual energy consumption to hourly load values. The reliability of load models is limited to a certain network because many local circumstances are different from utility to utility and time to time. Therefore there is a need to make improvements in the load models. Distribution load estimation (DLE) is the method developed here to improve load estimates from the load models. The method is also quite cheap to apply as it utilises information that is already available in SCADA systems

  17. Wind Loads on Structures

    DEFF Research Database (Denmark)

    Dyrbye, Claes; Hansen, Svend Ole

    pressure to structural response) and design criteria. Starting with an introduction of the wind load chain, the book moves on to meteorological considerations, atmospheric boundary layer, static wind load, dynamic wind load and scaling laws used in wind-tunnel tests. The dynamic wind load covers vibrations......Wind loads have to be taken into account when designing civil engineering structures. The wind load on structures can be systematised by means of the wind load chain: wind climate (global), terrain (wind at low height), aerodynamic response (wind load to pressure), mechanical response (wind...

  18. Botulinum toxin: examining duration of effect in facial aesthetic applications.

    Science.gov (United States)

    Flynn, Timothy Corcoran

    2010-01-01

    Patient satisfaction with botulinum toxin treatment is a key success factor in aesthetic procedures and is governed by the interaction of numerous variables. Duration of effect is important because it influences retreatment intervals as well as affecting cost and convenience to the patient. In order to review the evidence on the duration of benefit associated with various commercial formulations of botulinum toxin, MEDLINE was searched using the following terms: 'botulinum' and 'duration'/'retreatment' (limits: 'clinical trials,' 'meta-analyses,' 'English'). I also searched my existing reference files, reference lists of identified articles, and meeting/conference abstracts to ensure completeness. The focus was on clinical medicine and aesthetic trials. To be eligible for the analysis, studies had to include efficacy assessments at multiple timepoints. To estimate duration of benefit, the following outcomes were examined and summarized: responder rates, mean wrinkle severity scores at various timepoints (with or without changes from baseline), and relapse rates. Duration at both repose and maximum attempted muscle contraction was considered when provided. Where possible, duration was assessed by formulation and dose. The initial search yielded 164 articles. Of these, 35 included an adequate measure of duration in aesthetic indications. The majority of these (22) were on the glabellar area. Study designs and endpoints were highly heterogeneous, and duration of effect varied between studies. Several studies with the BOTOX Cosmetic (onabotulinumtoxinA; Allergan, Inc., Irvine, CA, USA) formulation of botulinum toxin type A (BoNTA) included relapse rates, defined conservatively as return to baseline levels of line severity for two consecutive visits approximately 30 days apart (at repose and maximum contraction). In these studies, duration of effect ranged from 3 to 5 months in female patients and from 4 to 6 months in male patients. Individual patients had longer

  19. Enhancement of a modified Mediterranean-style, low glycemic load diet with specific phytochemicals improves cardiometabolic risk factors in subjects with metabolic syndrome and hypercholesterolemia in a randomized trial

    Directory of Open Access Journals (Sweden)

    Babish John G

    2008-11-01

    Full Text Available Abstract Background As the worldwide dietary pattern becomes more westernized, the metabolic syndrome is reaching epidemic proportions. Lifestyle modifications including diet and exercise are recommended as first-line intervention for treating metabolic syndrome. Previously, we reported that a modified Mediterranean-style, low glycemic load diet with soy protein and phytosterols had a more favorable impact than the American Heart Association Step 1 diet on cardiovascular disease (CVD risk factors. Subsequently, we screened for phytochemicals with a history of safe use that were capable of increasing insulin sensitivity through modulation of protein kinases, and identified hops rho iso-alpha acid and acacia proanthocyanidins. The objective of this study was to investigate whether enhancement of a modified Mediterranean-style, low glycemic load diet (MED with specific phytochemicals (soy protein, phytosterols, rho iso-alpha acids and proanthocyanidins; PED could improve cardiometabolic risk factors in subjects with metabolic syndrome and hypercholesterolemia. Methods Forty-nine subjects with metabolic syndrome and hypercholesterolemia, aged 25–80, entered a randomized, 2-arm, 12-week intervention trial; 23 randomized to the MED arm; 26 to the PED arm. Forty-four subjects completed at least 8 weeks [MED (n = 19; PED (n = 25]. All subjects were instructed to follow the same aerobic exercise program. Three-day diet diaries and 7-day exercise diaries were assessed at each visit. Fasting blood samples were collected at baseline, 8 and 12 weeks for analysis. Results Both arms experienced equal weight loss (MED: -5.7 kg; PED: -5.9 kg. However, at 12 weeks, the PED arm experienced greater reductions (P P P P P Conclusion These results demonstrate that specific phytochemical supplementation increased the effectiveness of the modified Mediterranean-style low glycemic load dietary program on variables associated with metabolic syndrome and CVD.

  20. Developing Project Duration Models in Software Engineering

    Institute of Scientific and Technical Information of China (English)

    Pierre Bourque; Serge Oligny; Alain Abran; Bertrand Fournier

    2007-01-01

    Based on the empirical analysis of data contained in the International Software Benchmarking Standards Group(ISBSG) repository, this paper presents software engineering project duration models based on project effort. Duration models are built for the entire dataset and for subsets of projects developed for personal computer, mid-range and mainframeplatforms. Duration models are also constructed for projects requiring fewer than 400 person-hours of effort and for projectsre quiring more than 400 person-hours of effort. The usefulness of adding the maximum number of assigned resources as asecond independent variable to explain duration is also analyzed. The opportunity to build duration models directly fromproject functional size in function points is investigated as well.

  1. Heating load of envelope and energy efficiency correction factor for orientation of civil buildings%民用建筑围护结构负荷与节能朝向修正率

    Institute of Scientific and Technical Information of China (English)

    刘艳峰; 王登甲; 张薇

    2013-01-01

    In the current heating design standard, the value scope of the correction factor for orientation of building envelope heating loads is rather large, and it cannot reflect the differences of solar radiation intensities in various regions which results in that the design calculation results fail to match the respect practical situation. The related energy efficiency design standard does not take the orientation correction into account. Synthetically considering graded solar energy zoning and building thermotechnical design zoning standard, chooses the representative city of every region. Calculates and obtains heating load and energy efficiency correction factors for orientation for wider and more accurate application.%在现行暖通设计规范中,围护结构负荷朝向修正率取值范围较大,且无法体现太阳辐照度地区差异引起的差别,导致不同地区设计计算结果与实际朝向负荷不相符.相关节能设计标准中亦未考虑朝向修正.综合考虑太阳能热能等级分区和建筑热工设计分区划分标准,选取典型城市,计算得到了适用范围广、较准确的负荷朝向修正率和节能朝向修正率.

  2. 14 CFR 23.363 - Side load on engine mount.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Side load on engine mount. 23.363 Section....363 Side load on engine mount. (a) Each engine mount and its supporting structure must be designed for a limit load factor in a lateral direction, for the side load on the engine mount, of not less...

  3. Association between risk factors, basal viral load, virus genotype and the degree of liver fibrosis with the response to the therapy in patients with chronic hepatitis C virus infection

    Directory of Open Access Journals (Sweden)

    Vuković Vuk R.

    2015-01-01

    Full Text Available Background/Aim. Hepatitis C is an important sociomedical problem worldwide due to frequent progression to chronic disease, occurrence of liver cirrhosis and hepatocellular carcinoma. Standard pegylated interferon alfa 2a plus ribavirin therapy results in resolution of infection only in 50% of patients. The aim of this study was to determine the association of various factors with response to the therapy in patients with chronic hepatitis C virus (HCV infection. Age and sex of patients, inoculation risk factors, histopathological changes in the liver, viral load and HCV genotype were analyzed. Methods. The study included a group of 121 patients with chronic HCV infection. The treatment was carried out 24 weeks for virus genotype 2 and 3, and 48 weeks for genotype 1 and 4. The degree of histopathological changes in the liver was determined by hematoxylin and eosin staining, whereas polimerase chain reaction was used for HCV genotyping. Results. In the group of non-responding patients genotype 1 was represented with 100%, while in the other groups, although predominantly present, its percentage was lower. Unresponsiveness to therapy and relapse of disease were associated with higher viral load and advanced fibrosis. Intravenous use of psychoactive substances, as a risk factor, was present in a high percentage in the group of patients with sustained response, while blood transfusion and dialysis were leading risk factors in the group of relapse responders and non-responders. Conclusion. The results of our study showed that the treatment outcome of chronic HCV infection was associated with baseline HCV ribonucleic acid, HCV genotype, route of infection and the degree of histopathological changes in the liver. [Projekat Ministarstva nauke Republike Srbije, br. III41010

  4. Analysis models for variables associated with breastfeeding duration.

    Science.gov (United States)

    dos S Neto, Edson Theodoro; Zandonade, Eliana; Emmerich, Adauto Oliveira

    2013-09-01

    OBJECTIVE To analyze the factors associated with breastfeeding duration by two statistical models. METHODS A population-based cohort study was conducted with 86 mothers and newborns from two areas primary covered by the National Health System, with high rates of infant mortality in Vitória, Espírito Santo, Brazil. During 30 months, 67 (78%) children and mothers were visited seven times at home by trained interviewers, who filled out survey forms. Data on food and sucking habits, socioeconomic and maternal characteristics were collected. Variables were analyzed by Cox regression models, considering duration of breastfeeding as the dependent variable, and logistic regression (dependent variables, was the presence of a breastfeeding child in different post-natal ages). RESULTS In the logistic regression model, the pacifier sucking (adjusted Odds Ratio: 3.4; 95%CI 1.2-9.55) and bottle feeding (adjusted Odds Ratio: 4.4; 95%CI 1.6-12.1) increased the chance of weaning a child before one year of age. Variables associated to breastfeeding duration in the Cox regression model were: pacifier sucking (adjusted Hazard Ratio 2.0; 95%CI 1.2-3.3) and bottle feeding (adjusted Hazard Ratio 2.0; 95%CI 1.2-3.5). However, protective factors (maternal age and family income) differed between both models. CONCLUSIONS Risk and protective factors associated with cessation of breastfeeding may be analyzed by different models of statistical regression. Cox Regression Models are adequate to analyze such factors in longitudinal studies.

  5. Photovoltaic array capacity determined by considering the environmental factors for load patterns; Fuka pattern ni taisuru kankyo inshi wo koryoshita taiyo denchi array yoryo no kettei

    Energy Technology Data Exchange (ETDEWEB)

    Kameyama, N.; Higuchi, T.; Yamagami, Y.; Tani, T. [Science University of Tokyo, Tokyo (Japan). Faculty of Engineering

    1997-01-30

    Effectiveness of the spectral method was confirmed for system interconnection type photovoltaic (PV) power generation systems, and PV array capacity determined in harmony with the power load was investigated. In this study, system interconnection type PV power generation systems with polycrystalline Si and amorphous Si PV cell modules were discussed. The output electric energy evaluated by the spectral method was compared with that evaluated by the conventional method only considering the cell temperature. Obtained results are as follows. For the polycrystalline Si, the differences between solar supply rates in summer evaluated by the both methods and measured value were less than 2%, which resulted in the accurate determination. For the amorphous Si, however, the difference less than 3% was obtained by the spectral method and that less than 11% was obtained by the conventional method. The spectral method provided higher accuracy. When constructing a system with large array capacity, it was found that the optimum design of PV power generation system can be performed using the spectral method with less array capacity than using the conventional method. 4 refs., 9 figs., 4 tabs.

  6. Chloride concentrations, loads, and yields in four watersheds along Interstate 95, southeastern Connecticut, 2008-11: factors that affect peak chloride concentrations during winter storms

    Science.gov (United States)

    Brown, Craig J.; Mullaney, John R.; Morrison, Jonathan; Martin, Joseph W.; Trombley, Thomas J.

    2015-07-01

    Chloride (Cl-) concentrations and loads and other water chemistry characteristics were assessed to evaluate potential effects of road-deicer applications on streamwater quality in four watersheds along Interstate 95 (I–95) in southeastern Connecticut from November 1, 2008, through September 30, 2011. Streamflow and water quality were studied in the Four Mile River, Oil Mill Brook, Stony Brook, and Jordan Brook watersheds, where developed land ranged from 9 to 32 percent. Water-quality samples were collected and specific conductance was measured continuously at paired water-quality monitoring sites, upstream and downstream from I–95. Specific conductance values were related to Cl- concentrations to assist in determining the effects of road-deicing operations on the levels of Cl-in the streams. Streamflow and water-quality data were compared with weather data and with the timing, amount, and composition of deicers applied to State highways. Grab samples were collected during winter stormwater-runoff events, such as winter storms or periods of rain or warm temperatures in which melting takes place. Grab samples were also collected periodically during the spring and summer and during base-flow conditions.

  7. Photovoltaic array capacity determined by considering the environmental factors for load patterns; Fuka pattern ni taisuru kankyo inshi wo koryoshita taiyo denchi array yoryo no kettei

    Energy Technology Data Exchange (ETDEWEB)

    Kameyama, N.; Higuchi, T.; Yamagami, Y.; Tani, T. [Science University of Tokyo, Tokyo (Japan). Faculty of Engineering

    1997-01-30

    Effectiveness of the spectral method was confirmed for system interconnection type photovoltaic (PV) power generation systems, and PV array capacity determined in harmony with the power load was investigated. In this study, system interconnection type PV power generation systems with polycrystalline Si and amorphous Si PV cell modules were discussed. The output electric energy evaluated by the spectral method was compared with that evaluated by the conventional method only considering the cell temperature. Obtained results are as follows. For the polycrystalline Si, the differences between solar supply rates in summer evaluated by the both methods and measured value were less than 2%, which resulted in the accurate determination. For the amorphous Si, however, the difference less than 3% was obtained by the spectral method and that less than 11% was obtained by the conventional method. The spectral method provided higher accuracy. When constructing a system with large array capacity, it was found that the optimum design of PV power generation system can be performed using the spectral method with less array capacity than using the conventional method. 4 refs., 9 figs., 4 tabs.

  8. Muscle preservation in long duration space missions: The eccentric factor

    Science.gov (United States)

    Buchanan, Paul; Dudley, Gary A.; Tesch, Per A.; Hather, Bruce M.

    1990-01-01

    In our quest to understand, and eventually prevent, the loss of muscle strength and mass that occurs during prolonged periods in microgravity, we have organized our research approach by systems and useful terrestrial analogs. Our hypothesis was that: The eccentric movement, or lengthening component, of dynamic, resistive exercise, is required for the production of the greatest gains in strength and muscle hypertrophy in the most metabolically efficient, and time effective manner. The exercises selected were leg presses, leg (knee) extensions, and hamstring curls. In this 30 week study, 38 male subjects, between the ages of 25 and 50, were divided into four groups. One group performed 5 sets of 8-12 repetitions per set of conventional concentric/eccentric (CON/ECC) exercises. Another group performed only the concentric (CON) movement on the same schedule. The third group performed twice the number of sets in the concentric only mode (CON/CON), and the last group served as controls. We interpret these data as convincing evidence that the eccentric component of heavy resistance training is required along with the concentric for the most effective increase in strength and muscle fiber size in the least time. We also conclude that such heavy exercise of any such muscle group need not consume inordinately long periods of time, and is quite satisfactorily effective when performed on 72 hour centers.

  9. 基于多因素加法模型的中期电力负荷预测%Multiple Factors Addictive Model for Mid-Term Electric Load Forecasting

    Institute of Scientific and Technical Information of China (English)

    翁金芳; 黄伟; 江育娥; 林劼

    2016-01-01

    提前准确预测所需电力负荷,做好电力规划是电力部门保证电力供应稳定不可或缺的重要环节.基于欧洲智能网络(EUNITE)竞赛电力数据和北美电力数据,提出一种多因素加法模型,进行中期电力预测.考虑到温度、假期、星期等因素对电力负荷产生不同的影响,拟合出这些因素与电力负荷之间的映射关系,相加得到电力负荷预测的函数.还比较了业界常用的7种不同的算法模型,使用6种不同指标对这些模型和多因素加法模型进行评估,实验结果发现,在这8种不同算法模型中,多因素加法模型有着更加精确的预测性能,运算速度比其他模型快,并且模型更加容易理解和解释.%Accuracy forecasting of electric load is important for power system to make plan. A Multiple Factors Addictive (MFA) model is proposed to predict mid-term electric load based on Europe (EUNITE) competition dataset and North American electric dataset. Firstly, MFA considers factors such as temperature, holiday, and week separately to fit functions for electric loads. And then all these fitted functions are added together to a unified function, which is used to make prediction of the electric load. Seven other state-of-art algorithms which are popular in the field are also used to make forecasting. The performances of prediction models are evaluated by using 6 different metrics. Compared with 7 other kinds of different models prediction results, MFA has the advantages of more accurate forecasting performance and faster operational speed, and is simple and easy to understand.

  10. Segmental duration in Parkinsonian French speech.

    Science.gov (United States)

    Duez, Danielle

    2009-01-01

    The present study had 2 main objectives: (1) examine the effect of Parkinson's disease (PD) on vowel and consonant duration in French read speech and (2) investigate whether the durational contrasts of consonants and vowels are maintained or compromised. The data indicated that the consonant durations were shortened in Parkinsonian speech (PS), compared to control speech (CS). However, this shortening was consonant dependent: unvoiced occlusives and fricatives were significantly shortened compared to other consonant categories. All vowels were slightly longer in PS than in CS, however, the observed differences were below the level of significance. Despite significant shortening of some consonant categories, the general pattern of intrinsic duration was maintained in PS. There was slightly less agreement for vowels with the normal contrast of intrinsic durations, possibly because vowel durational contrasts are more sensitive to PD disorders. Most PD patients tended to maintain the intrinsic duration contrasts of both vowels and consonants, suggesting that low-level articulatory constraints operate in a similar way and with the same weight in PS and CS. Copyright 2009 S. Karger AG, Basel.

  11. Unemployment Duration over the Business Cycle

    DEFF Research Database (Denmark)

    Rosholm, Michael

    1996-01-01

    In this paper I study the way in which individual unemployment durations vary over the business cycle, as measured by the aggregate unemployment rate. I decompose the cyclical variations in observed unemployment durations into a composition al and a general part. The compositional part consists...... of variations in observed as well as unobserved average individual-specific heterogeneity amongst those flowing into unemployment. The main finding is that the major part (but not all) of the variations in unemployment durations is caused by variations in macroeconomic conditions (i.e. in the aggregate...... unemployment rate) rathan than by changes in the composition of those becoming unemployed....

  12. Plasma Cytokine Levels During Long-Duration Spaceflight

    Science.gov (United States)

    Crucian, Brian E.; Zwart, Sara R.; Quiriarte, Heather A.; Smith, Scott M.; Sams, Clarence F.

    2011-01-01

    Reduced T cell, granulocyte, NK and monocyte function have all been reported following both long and short duration spaceflight, however these data indicate crews are generally not experiencing inflammatory or adaptive immune activation during spaceflight. There appear to be varied individual crew responses, and specific relationships between cytokines and markers of iron status and muscle turnover that warrant further evaluation. Increases in growth factors and chemokines may indicate other types of adaptation occurring during spaceflight, such as attempts to overcome diminished immunocyte function.

  13. A feasibility test to estimate the duration of phytoextraction of heavy metals from polluted soils

    NARCIS (Netherlands)

    Japenga, J.; Koopmans, G.F.; Song, J.; Romkens, P.F.A.M.

    2007-01-01

    The practical applicability of heavy metal (HM) phytoextraction depends heavily on its duration. Phytoextraction duration is the main cost factor for phytoextraction, both referring to recurring economic costs during phytoextraction and to the cost of the soil having no economic value during

  14. The determinants of sick leave durations of Dutch self-employed

    NARCIS (Netherlands)

    Spierdijk, Laura; van Lomwel, Gijsbert; Peppelman, Wilko

    2009-01-01

    This paper analyzes sickness absenteeism among self-employed in the Netherlands. Using a unique data set provided by a large Dutch private insurance company, we assess the determinants of sick leave durations. Our study suggests that several risk factors affect the sick leave durations of self-emplo

  15. Effects of Vowel Duration and Vowel Quality on Vowel-to-Vowel Coarticulation

    Science.gov (United States)

    Mok, Peggy P. K.

    2011-01-01

    This work investigates how vowel duration and vowel quality affect degrees of vowel-to-vowel coarticulation. The effects of these two factors on vowel-to-vowel coarticulation have previously received little study. Phonological durational differences due to vowel length distinction were examined in Thai. It was hypothesized that shorter vowel…

  16. A feasibility test to estimate the duration of phytoextraction of heavy metals from polluted soils

    NARCIS (Netherlands)

    Japenga, J.; Koopmans, G.F.; Song, J.; Romkens, P.F.A.M.

    2007-01-01

    The practical applicability of heavy metal (HM) phytoextraction depends heavily on its duration. Phytoextraction duration is the main cost factor for phytoextraction, both referring to recurring economic costs during phytoextraction and to the cost of the soil having no economic value during phytoex

  17. Combined use of serum adiponectin and tumor necrosis factor-alpha receptor 2 levels was comparable to 2-hour post-load glucose in diabetes prediction.

    Directory of Open Access Journals (Sweden)

    Yu-Cho Woo

    Full Text Available BACKGROUND: Adipose tissue inflammation and dysregulated adipokine secretion are implicated in obesity-related insulin resistance and type 2 diabetes. We evaluated the use of serum adiponectin, an anti-inflammatory adipokine, and several proinflammatory adipokines, as biomarkers of diabetes risk and whether they add to traditional risk factors in diabetes prediction. METHODS: We studied 1300 non-diabetic subjects from the prospective Hong Kong Cardiovascular Risk Factor Prevalence Study (CRISPS. Serum adiponectin, tumor necrosis factor-alpha receptor 2 (TNF-α R2, interleukin-6 (IL-6, adipocyte-fatty acid binding protein (A-FABP and high-sensitivity C-reactive protein (hsCRP were measured in baseline samples. RESULTS: Seventy-six participants developed diabetes over 5.3 years (median. All five biomarkers significantly improved the log-likelihood of diabetes in a clinical diabetes prediction (CDP model including age, sex, family history of diabetes, smoking, physical activity, hypertension, waist circumference, fasting glucose and dyslipidaemia. In ROC curve analysis, "adiponectin + TNF-α R2" improved the area under ROC curve (AUC of the CDP model from 0.802 to 0.830 (P = 0.03, rendering its performance comparable to the "CDP + 2-hour post-OGTT glucose" model (AUC = 0.852, P = 0.30. A biomarker risk score, derived from the number of biomarkers predictive of diabetes (low adiponectin, high TNF-α R2, had similar performance when added to the CDP model (AUC = 0.829 [95% CI: 0.808-0.849]. CONCLUSIONS: The combined use of serum adiponectin and TNF-α R2 as biomarkers provided added value over traditional risk factors for diabetes prediction in Chinese and could be considered as an alternative to the OGTT.

  18. Impact load mitigation in sandwich beams using local resonators

    CERN Document Server

    Sharma, B

    2015-01-01

    Dynamic response of sandwich beams with resonators embedded in the cores subjected to impact loads is studied. Using finite element models the effectiveness of various local resonator frequencies under a given impact load is compared to the behavior of an equivalent mass beam. It is shown that addition of appropriately chosen local resonators into the sandwich beam is an effective method of improving its flexural bending behavior under impact loads. The effect of a given local resonance frequency under different impact load durations is also studied. It is demonstrated that the choice of appropriate local resonance frequency depends on the impact duration. Further, by performing transverse impact experiments, the finite element models are verified and the advantage of using internal resonators under impact loading conditions is demonstrated.

  19. 14 CFR 25.511 - Ground load: unsymmetrical loads on multiple-wheel units.

    Science.gov (United States)

    2010-01-01

    ... differential equal to 2/3 of the most unfavorable combination of diameter variations that is obtained when... tires— (1) The applied side or drag load factor, or both factors, at the center of gravity must be the most critical value up to 50 percent and 40 percent, respectively, of the limit side or drag load...

  20. Model-Checking Discrete Duration Calculus

    DEFF Research Database (Denmark)

    Hansen, Michael Reichhardt

    1994-01-01

    Duration calculus was introduced by Chaochen Zhou et al. (1991) as a logic to specify and reason about requirements for real-time systems. It is an extension of interval temporal logic where one can reason about integrated constraints over time-dependent and Boolean valued states without explicit...... mention of absolute time. Several major case studies have shown that duration calculus provides a high level of abstraction for both expressing and reasoning about specifications. Using timed automata one can express how real-time systems can be constructed at a level of detail which is close to an actual...... implementation. We consider in the paper the correctness of timed automata with respect to duration calculus formulae. For a subset of duration calculus, we show that one can automatically verify whether a timed automaton ℳ is correct with respect to a formula 𝒟, abbreviated ℳ|=𝒟, i.e. one...

  1. Model-Checking Discrete Duration Calculus

    DEFF Research Database (Denmark)

    Hansen, Michael Reichhardt

    1994-01-01

    Duration calculus was introduced by Chaochen Zhou et al. (1991) as a logic to specify and reason about requirements for real-time systems. It is an extension of interval temporal logic where one can reason about integrated constraints over time-dependent and Boolean valued states without explicit...... mention of absolute time. Several major case studies have shown that duration calculus provides a high level of abstraction for both expressing and reasoning about specifications. Using timed automata one can express how real-time systems can be constructed at a level of detail which is close to an actual...... implementation. We consider in the paper the correctness of timed automata with respect to duration calculus formulae. For a subset of duration calculus, we show that one can automatically verify whether a timed automaton ℳ is correct with respect to a formula 𝒟, abbreviated ℳ|=𝒟, i.e. one...

  2. Long Duration Space Shelter Shielding Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Physical Sciences Inc. (PSI) has developed fiber reinforced ceramic composites for radiation shielding that can be used for external walls in long duration manned...

  3. Carbohydrate-Loading: A Safe and Effective Method of Improving Endurance Performance.

    Science.gov (United States)

    Beeker, Richard T.; Israel, Richard G.

    Carbohydrate-loading prior to distance events is a common practice among endurance athletes. The purposes of this paper are to review previous research and to clarify misconceptions which may exist concerning carbohydrate-loading. The most effective method of carbohydrate-loading involves a training run of sufficient intensity and duration to…

  4. Prognostic factors in the development of opioid addiction

    Directory of Open Access Journals (Sweden)

    Vasila Talimbekova

    2011-04-01

    Full Text Available In 145 patients with opioid addiction were studied prognostic factors of the formation of the disease and their medical and social consequences. In the examined patients duration of the narcotization was from 1 year to 15 years. Analysis of studies showed that the most significant adverse prognostic factors, determining formation rate of medical and social consequences in opioid addiction, may include: perinatal pathology, personality deviation in the premorbid; early age of onset of drug use; hereditary load addictive and mental illness; condition of upbringing; alcohol abuse prior to narcotization; prescription of narcotization. These constitutionally-biological factors are informative indicators in the predicting the formation of opioid dependence.

  5. Breastfeeding behavior among adolescents: Initiation, duration, and exclusivity

    Science.gov (United States)

    Sipsma, Heather L.; Magriples, Urania; Divney, Anna; Gordon, Derrick; Gabzdyl, Elizabeth; Kershaw, Trace

    2013-01-01

    Purpose Despite a substantial amount of evidence on breastfeeding among non-adolescent mothers, research and strategies uniquely designed to target adolescent mothers are critical as their rates of breastfeeding are disproportionately low and their transition to parenthood is often unlike that of older mothers. Literature to date, however, offers limited evidence for designing effective interventions. Therefore, we aim to fill this gap in the literature by examining breastfeeding behaviors among a cohort of female adolescents as they transition to parenthood. Methods Data are derived from a longitudinal cohort of pregnant adolescent females (ages 14-21) and their male partners followed from pregnancy through 6 months postpartum. Means and frequencies were used to describe breastfeeding experiences, breastfeeding behaviors, and sociodemographic characteristics. Multivariate logistic regression and Cox proportional hazards models were used to identify factors independently associated with breastfeeding initiation, exclusive breastfeeding, and breastfeeding duration. Results Approximately 71% initiated breastfeeding. Intending to breastfeed, having had complications in labor and delivery, and lower social support were associated with greater odds of breastfeeding initiation. Of the adolescent mothers who initiated breastfeeding, 84% had stopped by 6 months postpartum and among those, average breastfeeding duration was 5 weeks. Participants who exclusively breastfed had longer breastfeeding duration, and participants who had experienced intimate partner violence had shorter breastfeeding duration. Obese women and women who had more difficulty breastfeeding had lower odds of exclusive breastfeeding. Conclusions Enhanced clinical support and the promotion of exclusive breastfeeding should be considered when designing interventions to improve breastfeeding rates among adolescent mothers. PMID:23725911

  6. On a Possible Unified Scaling Law for Volcanic Eruption Durations.

    Science.gov (United States)

    Cannavò, Flavio; Nunnari, Giuseppe

    2016-03-01

    Volcanoes constitute dissipative systems with many degrees of freedom. Their eruptions are the result of complex processes that involve interacting chemical-physical systems. At present, due to the complexity of involved phenomena and to the lack of precise measurements, both analytical and numerical models are unable to simultaneously include the main processes involved in eruptions thus making forecasts of volcanic dynamics rather unreliable. On the other hand, accurate forecasts of some eruption parameters, such as the duration, could be a key factor in natural hazard estimation and mitigation. Analyzing a large database with most of all the known volcanic eruptions, we have determined that the duration of eruptions seems to be described by a universal distribution which characterizes eruption duration dynamics. In particular, this paper presents a plausible global power-law distribution of durations of volcanic eruptions that holds worldwide for different volcanic environments. We also introduce a new, simple and realistic pipe model that can follow the same found empirical distribution. Since the proposed model belongs to the family of the self-organized systems it may support the hypothesis that simple mechanisms can lead naturally to the emergent complexity in volcanic behaviour.

  7. Strong motion duration and earthquake magnitude relationships

    Energy Technology Data Exchange (ETDEWEB)

    Salmon, M.W.; Short, S.A. [EQE International, Inc., San Francisco, CA (United States); Kennedy, R.P. [RPK Structural Mechanics Consulting, Yorba Linda, CA (United States)

    1992-06-01

    Earthquake duration is the total time of ground shaking from the arrival of seismic waves until the return to ambient conditions. Much of this time is at relatively low shaking levels which have little effect on seismic structural response and on earthquake damage potential. As a result, a parameter termed ``strong motion duration`` has been defined by a number of investigators to be used for the purpose of evaluating seismic response and assessing the potential for structural damage due to earthquakes. This report presents methods for determining strong motion duration and a time history envelope function appropriate for various evaluation purposes, for earthquake magnitude and distance, and for site soil properties. There are numerous definitions of strong motion duration. For most of these definitions, empirical studies have been completed which relate duration to earthquake magnitude and distance and to site soil properties. Each of these definitions recognizes that only the portion of an earthquake record which has sufficiently high acceleration amplitude, energy content, or some other parameters significantly affects seismic response. Studies have been performed which indicate that the portion of an earthquake record in which the power (average rate of energy input) is maximum correlates most closely with potential damage to stiff nuclear power plant structures. Hence, this report will concentrate on energy based strong motion duration definitions.

  8. Satellite-Based Sunshine Duration for Europe

    Directory of Open Access Journals (Sweden)

    Bodo Ahrens

    2013-06-01

    Full Text Available In this study, two different methods were applied to derive daily and monthly sunshine duration based on high-resolution satellite products provided by the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT Satellite Application Facility on Climate Monitoring using data from Meteosat Second Generation (MSG SEVIRI (Spinning Enhanced Visible and Infrared Imager. The satellite products were either hourly cloud type or hourly surface incoming direct radiation. The satellite sunshine duration estimates were not found to be significantly different using the native 15-minute temporal resolution of SEVIRI. The satellite-based sunshine duration products give additional spatial information over the European continent compared with equivalent in situ-based products. An evaluation of the satellite sunshine duration by product intercomparison and against station measurements was carried out to determine their accuracy. The satellite data were found to be within ±1 h/day compared to high-quality Baseline Surface Radiation Network or surface synoptic observations (SYNOP station measurements. The satellite-based products differ more over the oceans than over land, mainly because of the treatment of fractional clouds in the cloud type-based sunshine duration product. This paper presents the methods used to derive the satellite sunshine duration products and the performance of the different retrievals. The main benefits and disadvantages compared to station-based products are also discussed.

  9. Collective behaviors of book holding durations

    Science.gov (United States)

    Li, Ren-De; Guo, Qiang; Han, Jing-Ti; Liu, Jian-Guo

    2016-10-01

    Duration can directly reflect the collective reading behaviors of library user book holding. In this paper, by introducing the burstiness and memory coefficients, we empirically investigate the collective book holding behavior of three university libraries. The statistical results show that there are similar properties among the students with different backgrounds, presenting the burstiness = - 0.2 and memory = 0.5 for three datasets, which indicates that memory and random effects coexist in student book holding durations. In addition, we analyze the behavior patterns without duplicate durations by merging a series of books borrowed and returned at the same time. The results show the average burstiness B increases to -0.16 and memory M drops to 0.16 for three datasets, which indicates that both duplicate behavior and student's preference affect the memory effect. Furthermore, we present a model which assumes student's next book holding duration follows the previous one with probability p, and with probability 1 - p, the student would hold the book independently. The experimental results show that the presented model can reproduce the burstiness and memory effect of student book holding durations when p = 0.5 for empirical datasets and p = 0.2 for de-duplicate datasets, which indicate that the student's preferential holding behavior occurs with the probability p. This work helps in deeply understanding the regularity of duration-based human behaviors.

  10. Call Duration Characteristics based on Customers Location

    Directory of Open Access Journals (Sweden)

    Žvinys Karolis

    2014-05-01

    Full Text Available Nowadays a lot of different researches are performed based on call duration distributions (CDD analysis. However, the majority of studies are linked with social relationships between the people. Therefore the scarcity of information, how the call duration is associated with a user's location, is appreciable. The goal of this paper is to reveal the ties between user's voice call duration and the location of call. For this reason we analyzed more than 5 million calls from real mobile network, which were made over the base stations located in rural areas, roads, small towns, business and entertainment centers, residential districts. According to these site types CDD’s and characteristic features for call durations are given and discussed. Submitted analysis presents the users habits and behavior as a group (not an individual. The research showed that CDD’s of customers being them in different locations are not equal. It has been found that users at entertainment, business centers are tend to talk much shortly, than people being at home. Even more CDD can be distorted strongly, when machinery calls are evaluated. Hence to apply a common CDD for a whole network it is not recommended. The study also deals with specific parameters of call duration for distinguished user groups, the influence of network technology for call duration is considered.

  11. Simulation of PV/FC power hybrid system. Change of system capacity with load form factor; Taiyoko hatsuden nenryo denchi hybrid system no simulation. Fuka keijoritsu ni yoru system yoryo no henka

    Energy Technology Data Exchange (ETDEWEB)

    Sekiguchi, N.; Tani, T. [Science University of Tokyo, Tokyo (Japan)

    1997-11-25

    Study is conducted of a photovoltaic/fuel-cell hybrid system whose power storage is a hydrogen storage that uses a hydrogen absorbing alloy. In a simulation in this research, the solar cell conversion efficiency is changed from 15.0% to 21.0% and the fuel cell power conversion efficiency from 40.0% to 50.0%, and the resultant changes in the capacity and operation rate are investigated for each of the devices in the system. The findings follow. A 1.0% change in the solar cell conversion efficiency results in a 4.8kW change in the solar cell capacity and a 1.6-ton change in the hydrogen storage capacity. With a 1.0% change in the fuel cell power conversion efficiency, there is a 14.7kW change in the solar cell capacity and a 5.3-ton change in the hydrogen storage capacity. The fuel cell capacity is not dependent on the solar cell conversion efficiency or fuel cell power conversion efficiency but on the maximum load in each of the load form factors. The rate of occurrence of an operation rate of less than 30% is 54.7% both in DC/DC converter and hydrogen generator, 24.6% in fuel cells, and 16.7% in the DC/DC inverter. 7 refs., 7 figs., 1 tab.

  12. The Relationship between Age and Illness Duration in Chronic Fatigue Syndrome

    Directory of Open Access Journals (Sweden)

    Elizabeth Kidd

    2016-04-01

    Full Text Available Chronic fatigue syndrome (CFS is a debilitating illness, but it is unclear if patient age and illness duration might affect symptoms and functioning of patients. In the current study, participants were categorized into four groups based upon age (under or over age 55 and illness duration (more or less than 10 years. The groups were compared on functioning and symptoms. Findings indicated that those who were older with a longer illness duration had significantly higher levels of mental health functioning than those who were younger with a shorter or longer illness duration and the older group with a shorter illness duration. The results suggest that older patients with an illness duration of over 10 years have significantly higher levels of mental health functioning than the three other groups. For symptoms, the younger/longer illness duration group had significantly worse immune and autonomic domains than the older/longer illness group. In addition, the younger patients with a longer illness duration displayed greater autonomic and immune symptoms in comparison to the older group with a longer illness duration. These findings suggest that both age and illness duration need to be considered when trying to understand the influence of these factors on patients.

  13. Load forecasting method considering temperature effect for distribution network

    Directory of Open Access Journals (Sweden)

    Meng Xiao Fang

    2016-01-01

    Full Text Available To improve the accuracy of load forecasting, the temperature factor was introduced into the load forecasting in this paper. This paper analyzed the characteristics of power load variation, and researched the rule of the load with the temperature change. Based on the linear regression analysis, the mathematical model of load forecasting was presented with considering the temperature effect, and the steps of load forecasting were given. Used MATLAB, the temperature regression coefficient was calculated. Using the load forecasting model, the full-day load forecasting and time-sharing load forecasting were carried out. By comparing and analyzing the forecast error, the results showed that the error of time-sharing load forecasting method was small in this paper. The forecasting method is an effective method to improve the accuracy of load forecasting.

  14. Simulating liquid loading in gas wells

    NARCIS (Netherlands)

    Schiferli, W.; Belfroid, S.P.C.; Savenko, S.; Veeken, C.A.M.; Hu, B.

    2010-01-01

    This paper describes work performed by the authors over the last several years to better understand the factors affecting the onset of liquid loading. To further improve the prediction of onset of liquid loading, efforts were undertaken to better model the process. Dedicated codes as well as a comme

  15. High Power Disk Loaded Guide Load

    Energy Technology Data Exchange (ETDEWEB)

    Farkas, Z.D.; /SLAC

    2006-02-22

    A method to design a matching section from a smooth guide to a disk-loaded guide, using a variation of broadband matching, [1, 2] is described. Using this method, we show how to design high power loads. The load consists of a disk-loaded coaxial guide operating in the TE{sub 01}-mode. We use this mode because it has no electric field terminating on a conductor, has no axial currents, and has no current at the cylinder-disk interface. A high power load design that has -35 dB reflection and a 200 MHz, -20 dB bandwidth, is presented. It is expected that it will carry the 600 MW output peak power of the pulse compression network. We use coaxial geometry and stainless steel material to increase the attenuation per cell.

  16. Analysis on factors of having influences on the pile quality and loading capacity of the bored pile%影响钻孔灌注桩桩身质量和承载力的因素分析

    Institute of Scientific and Technical Information of China (English)

    梁亦垅

    2009-01-01

    结合工程实践,对影响钻孔灌注桩柱身质量和承载力的因素进行了分析,从成孔和成桩两方面提出了确保钻孔灌注桩桩身质量的方法,以积累钻孔灌注桩施工经验,推广钻孔灌注桩在工程中的应用.%Combining with project practice, the author analyzes the factors of having influences on the pile quality and loading capacity of the bored pile, provides methods of ensuring the pile quality of the bored pile from two aspects of hole forming and pile forming, so as to accumulate the constructionm experiences of the bored pile, improving the application of the bored pile on project.

  17. Exercise and pharmacological countermeasures for bone loss during long-duration space flight

    Science.gov (United States)

    Cavanagh, Peter R.; Licata, Angelo A.; Rice, Andrea J.

    2005-01-01

    Bone loss in the lower extremities and lumbar spine is an established consequence of long-duration human space flight. Astronauts typically lose as much bone mass in the proximal femur in 1 month as postmenopausal women on Earth lose in 1 year. Pharmacological interventions have not been routinely used in space, and countermeasure programs have depended solely upon exercise. However, it is clear that the osteogenic stimulus from exercise has been inadequate to maintain bone mass, due to insufficient load or duration. Attention has therefore been focused on several pharmacological interventions that have been successful in preventing or attenuating osteoporosis on Earth. Anti-resorptives are the class of drugs most commonly used to treat osteoporosis in postmenopausal women, notably alendronate sodium, risedronate sodium, zoledronic acid, and selective estrogen receptor modulators, such as raloxifene. There has also been considerable recent interest in anabolic agents such as parathyroid hormone (PTH) and teriparatide (rhPTH [1-34]). Vitamin D and calcium supplementation have also been used. Recent studies of kindreds with abnormally high bone mineral density have provided insight into the genetic regulation of bone mass. This has led to potential therapeutic interventions based on the LRP5, Wnt and BMP2 pathways. Another target is the RANK-L/osteoprotegerin signaling pathway, which influences bone turnover by regulating osteoclast formation and maturation. Trials using such therapies in space are being planned. Among the factors to be considered are dose-response relationships, bone quality, post-use recovery, and combination therapies--all of which may have unique characteristics when the drugs are used in space.

  18. Duration of estrus in relation to reproduction results in pigs on commercial farms.

    Science.gov (United States)

    Steverink, D W; Soede, N M; Groenland, G J; van Schie, F W; Noordhuizen, J P; Kemp, B

    1999-04-01

    This research was conducted to determine factors that influence duration of estrus, AI strategy, and reproduction results between and within commercial swine farms that use AI. Data from 15,186 sows and gilts on 55 farms for a period of 6.1+/-4.2 mo per farm were used in this study. The average duration of estrus was 48.4+/-1.0 h, ranging from 31 to 64 h, and was consistent from month to month within a farm (repeatability of 86%). Differences in duration of estrus between farms accounted for 23% of the total variation in duration of estrus. On most farms (n = 45), gilts showed a shorter (P farms and ranged from -7.4 to +1.3 h/d; four farms had a positive relationship. Farrowing rate decreased (P reproduction results were lower than when AI was performed before or at expected ovulation in sows. Duration of estrus was not related to farrowing rate or litter size in individual pigs. Number of inseminations per estrus, time of AI, and duration of estrus were correlated, which made it difficult to assess which of these factors was primarily related to the farrowing rate or litter size. Knowledge of average duration of estrus on farms and of factors that influence the duration of estrus on commercial farms can help to improve the efficiency of the AI strategy specific for each farm.

  19. Attenuation of the bacterial load in blood by pretreatment with granulocyte-colony-stimulating factor protects rats from fatal outcome and brain damage during Streptococcus pneumoniae meningitis

    DEFF Research Database (Denmark)

    Brandt, Christian T; Lundgren, Jens D; Lund, Søren Peter

    2004-01-01

    A model of pneumococcal meningitis in young adult rats receiving antibiotics once the infection was established was developed. The intent was to mimic clinical and histopathological features of pneumococcal meningitis in humans. The primary aim of the present study was to evaluate whether medical...... of meningitis result in reduced risks of death and brain damage. This beneficial effect is most likely achieved through improved control of the systemic disease....... postinfection did not alter the clinical or histological outcome relative to that for non-G-CSF-treated rats. The magnitude of bacteremia and pretreatment with G-CSF were found to be prognostic factors for both outcome and brain damage. In summary, elevated neutrophil levels prior to the development...

  20. The effect of insulin-loaded linear poly(ethylene glycol)-brush-like poly(l-lysine) block copolymer on renal ischemia/reperfusion-induced lung injury through downregulating hypoxia-inducible factor.

    Science.gov (United States)

    Tong, Fei; Tang, Xiangyuan; Li, Xin; Xia, Wenquan; Liu, Daojun

    2016-01-01

    The aim of this study was to observe the therapeutic effect of insulin-loaded linear poly(ethylene glycol)-brush-like poly(l-lysine) block copolymer poly(ethylene glycol)-b-(poly(ethylenediamine l-glutamate)-g-poly(l-lysine)) (PEG-b-(PELG-g-PLL) on renal ischemia/reperfusion-induced lung injury through downregulating hypoxia-inducible factor (HIF) as compared to free insulin. Sprague Dawley rats were pretreated with 30 U/kg insulin or insulin/PEG-b-(PELG-g-PLL) complex, and then subjected to 45 minutes of ischemia and 24 hours of reperfusion. The blood and lungs were collected, the level of serum creatinine and blood urea nitrogen were measured, and the dry/wet lung ratios, the activity of superoxide dismutase and myeloperoxidase, the content of methane dicarboxylic aldehyde and tumor necrosis factor-α, and the expression of HIF-1α and vascular endothelial growth factor (VEGF) were measured in pulmonary tissues. Both insulin and insulin/PEG-b-(PELG-g-PLL) preconditioning improved the recovery of renal function, reduced pulmonary oxidative stress injury, restrained inflammatory damage, and downregulated the expression of HIF-1α and VEGF as compared to ischemia/reperfusion group, while insulin/PEG-b-(PELG-g-PLL) significantly improved this effect.

  1. The effect of insulin-loaded linear poly(ethylene glycol)-brush-like poly(l-lysine) block copolymer on renal ischemia/reperfusion-induced lung injury through downregulating hypoxia-inducible factor

    Science.gov (United States)

    Tong, Fei; Tang, Xiangyuan; Li, Xin; Xia, Wenquan; Liu, Daojun

    2016-01-01

    The aim of this study was to observe the therapeutic effect of insulin-loaded linear poly(ethylene glycol)-brush-like poly(l-lysine) block copolymer poly(ethylene glycol)-b-(poly(ethylenediamine l-glutamate)-g-poly(l-lysine)) (PEG-b-(PELG-g-PLL) on renal ischemia/reperfusion-induced lung injury through downregulating hypoxia-inducible factor (HIF) as compared to free insulin. Sprague Dawley rats were pretreated with 30 U/kg insulin or insulin/PEG-b-(PELG-g-PLL) complex, and then subjected to 45 minutes of ischemia and 24 hours of reperfusion. The blood and lungs were collected, the level of serum creatinine and blood urea nitrogen were measured, and the dry/wet lung ratios, the activity of superoxide dismutase and myeloperoxidase, the content of methane dicarboxylic aldehyde and tumor necrosis factor-α, and the expression of HIF-1α and vascular endothelial growth factor (VEGF) were measured in pulmonary tissues. Both insulin and insulin/PEG-b-(PELG-g-PLL) preconditioning improved the recovery of renal function, reduced pulmonary oxidative stress injury, restrained inflammatory damage, and downregulated the expression of HIF-1α and VEGF as compared to ischemia/reperfusion group, while insulin/PEG-b-(PELG-g-PLL) significantly improved this effect. PMID:27175073

  2. Pharmacodynamics effect of nerve growth factor-loaded nanoparticles to induce PC12 cells%载神经生长因子纳米药物体外诱导PC12细胞的药效***★

    Institute of Scientific and Technical Information of China (English)

    包国庆; 龙大宏; 陈艳; 刘菲菲; 张君度

    2013-01-01

    BACKGROUND:It is found that the surface-modified polymer nanoparticles can pass through the blood-brain barrier, and improve the drug effects on the central nervous system diseases. OBJECTIVE:To prepare nerve growth factor-loaded high encapsulation efficiency nanoparticles with a iodegradable material, polyethylene glycol-polylactic acid glycolic acid copolymer, and to explore its effect on PC12 cel s. METHODS:Bovine serum albumin-loaded polyethylene glycol-polylactic acid glycolic acid copolymer nanoparticles were prepared using complex emulsion solvent diffusion method. The production process was screened by univariate analysis and orthogonal design method. The nanoparticle morphology was observed under scanning electron microscopy, and the average particle diameter and the dispersion index were measured by nanoparticle analyzer. The nanoparticle encapsulation efficiency and drug loading were analyzed by BCA method. Nanoparticle release in vitro was also investigated. After optimization of the preparation program, nerve growth factor-loaded polymer nanoparticles were prepared and applied to PC12 cel s. The cel s were then observed by inverted fluorescence microscope, and the induction effects, toxicity and slow-release effect of polyethylene glycol-polylactic acid glycolic acid copolymer nanoparticles loaded with nerve growth factor were evaluated. RESULTS AND CONCLUSION:Bovine serum albumin-loaded polyethylene glycol-polylactic acid glycolic acid copolymer nanoparticles were prepared by optimal method. The nanoparticles were spherical, and uniform in size, with an average particle size of (258.9±5.73) nm, and the encapsulation efficiency was (80.56±2.23)%. When the dosage within the aqueous phase was 10 mg, the drug loading was (4.24±0.12)%. The in vitro release of nanoparticles was in accordance with the Higuchi equation of. Release of the nanoparticles could be divided into two stages:initial burst release stage and late sustained release. The total

  3. 竖向荷载下的生态复合墙体内力计算及影响因素分析%CALCULATION OF INTERNAL FORCE AND INFLUENCE FACTORS ANALYSIS OF ECO-COMPOSITE WALL UNDER VERTICAL LOADING

    Institute of Scientific and Technical Information of China (English)

    侯莉娜; 黄炜; 田英侠

    2015-01-01

    生态复合墙体在竖向荷载作用下,墙体各组件(边框、肋格、填充砌块)之间存在协同工作关系。采用弹性地基梁理论,建立生态复合墙体在竖向荷载作用下的内力计算模型,定量地计算出各组件在竖向荷载作用下承担的内力,分析影响墙体受力分配关系的因素。理论分析与试验结果对比表明:该计算模型运用于竖向荷载作用下的生态复合墙体内力计算具有一定的精确度;各组件分配竖向荷载比例与暗梁刚度、边框柱刚度及复合墙板等效弹性模量等因素有关,边框柱刚度的影响小于暗梁刚度影响;当复合墙板等效弹性模量增大至30 GPa时,边框柱承担的荷载只占总荷载的18.4%。该研究结果为生态复合墙结构的抗震优化设计提供了一定的参考。%Under vertical loading, the three-part members of the eco-composite wall ( side frame, rib grids and filler blocks) work cooperatively.Based on the elastic foundation beam theory, the mechanical calculation model of the eco-composite wall was established.The internal force carried by each component was quantitatively calculated.The influence factors of the bearing performance of the components in the wall were analyzed.The comparison of theory analysis with experiment results showed that the calculation of the internal force had a certain degree of precision;the vertical loads carried by each component was related to such factors as the stiffness of side-frame column, the stiffness of concealed beam and the equivalent elastic modulus of the eco-composite slab.The stiffness of the side-frame beam had greater effect on the loads distribution than that of side-frame column.When the equivalent elastic modulus increased to 30 GPa, the proportion of the loading carried by the side-frame column was only 18.4% of the total load.The results of the research would provide an important theory foundation for the seismic optimum design of

  4. Hours of television viewing and sleep duration in children: a multicenter birth cohort study.

    Science.gov (United States)

    Marinelli, Marcella; Sunyer, Jordi; Alvarez-Pedrerol, Mar; Iñiguez, Carmen; Torrent, Maties; Vioque, Jesús; Turner, Michelle C; Julvez, Jordi

    2014-05-01

    This study used longitudinal data to examine potential associations between hours of television viewing and sleep duration in children. To examine the association between hours of television viewing and sleep duration in preschool and school-aged children. Longitudinal, multicenter study among birth cohorts in Menorca, Sabadell, and Valencia from the Spanish Infancia y Medio Ambiente (environment and childhood) project. The study sample included 1713 children (468 from Menorca, 560 from Sabadell, and 685 from Valencia). Parent-reported child television viewing duration measured in hours per day at 2 and 4 years of age in Sabadell and Valencia and at 6 and 9 years of age in Menorca. Parent-reported child sleep duration measured in hours per day at 2 and 4 years of age in Sabadell and Valencia and at 6 and 9 years of age in Menorca. In cross-sectional analysis, children with longer periods of television viewing reported at baseline (≥ 1.5 hours per day) had shorter sleep duration. Longitudinally, children with reported increases in television viewing duration over time (from <1.5 to ≥ 1.5 hours per day) had a reduction in sleep duration at follow-up visits. Results were similar when examining television viewing duration as a continuous variable, with each 1 hour per day of increased viewing decreasing sleep duration at follow-up visits (β = -0.11; 95% CI, -0.18 to -0.05). Associations were similar when television viewing duration was assessed during weekends and after adjusting for potential intermediate factors (child executive function and attention-deficit/hyperactivity disorder symptoms) and confounders (child physical activity level, parental mental health status, maternal IQ, and maternal marital status). Children spending longer periods watching television had shorter sleep duration. Changes in television viewing duration were inversely associated with changes in sleep duration in longitudinal analysis. Parents should consider avoiding long periods of

  5. Effects of breast-feeding duration, bottle-feeding duration and non-nutritive sucking habits on the occlusal characteristics of primary dentition

    OpenAIRE

    Chen, Xiaoxian; Xia, Bin; Ge, Lihong

    2015-01-01

    Background Early transition from breastfeeding and non-nutritive sucking habits may be related to occlusofacial abnormalities as environmental factors. Previous studies have not taken into account the potential for interactions between feeding practice, non-nutritive sucking habits and occlusal traits. This study assessed the effects of breast-feeding duration, bottle-feeding duration and non-nutritive sucking habits on the occlusal characteristics of primary dentition in 3–6-year-old childre...

  6. Sociosexuality, Morningness–Eveningness, and Sleep Duration

    Directory of Open Access Journals (Sweden)

    Christoph Randler

    2016-01-01

    Full Text Available Morningness–eveningness is the preference for different times of day for activity and sleep. Here, we addressed the effects of sleep behavior and morningness–eveningness on sociosexuality. Three hundred students (M age = 22.75 years, with 95% between 18 and 28 participated online, answering questions about morningness–eveningness (rMEQ [Reduced Morningness–Eveningness Questionnaire], midpoint of sleep on free days (MSF, sleep duration, and the Sociosexuality Orientation Inventory–Revised (SOI-R. The SOI-R contains three subscales, Behavior, Attitude, and Desire. Evening orientation and short sleep duration were related to a higher total SOI-R and to the three subscales. Based on the linear models, the strongest effect on sociosexuality was produced by gender (27% explained variance while age accounted for 6% of variance. Nonadditive variance explained by sleep–wake behavior was 7% (MSF, 4% (sleep duration, and 4% (rMEQ scores; 3% rMEQ-based typology. Older age was related to less-restricted sociosexuality, and men were less restricted than women in Attitude and Desire. Sleep duration and rMEQ scores were associated with Attitude and Desire; but only MSF was significantly related to Behavior. The data show that sleep–wake variables are associated with sociosexuality, with evening orientation and shorter sleep duration being related to a less-restricted sociosexuality.

  7. Brain-Derived Neurotrophic Factor Loaded PS80 PBCA Nanocarrier for In Vitro Neural Differentiation of Mouse Induced Pluripotent Stem Cells

    Science.gov (United States)

    Chung, Chiu-Yen; Lin, Martin Hsiu-Chu; Lee, I-Neng; Lee, Tsong-Hai; Lee, Ming-Hsueh; Yang, Jen-Tsung

    2017-01-01

    Brain derived neurotrophic factor (BDNF) can induce neural differentiation in stem cells and has the potential for repair of the nervous system. In this study, a polysorbate 80-coated polybutylcyanoacrylate nanocarrier (PS80 PBCA NC) was constructed to deliver plasmid DNAs (pDNAs) containing BDNF gene attached to a hypoxia-responsive element (HRE-cmvBDNF). The hypoxia-sensing mechanism of BDNF expression and inductiveness of the nano-formulation on mouse induced pluripotent stem cells (iPSCs) to differentiate into neurons following hypoxia was tested in vitro with immunofluorescent staining and Western blotting. The HRE-cmvBDNF appeared to adsorb onto the surface of PS80 PBCA NC, with a resultant mean diameter of 92.6 ± 1.0 nm and zeta potential of −14.1 ± 1.1 mV. HIF-1α level in iPSCs was significantly higher in hypoxia, which resulted in a 51% greater BDNF expression when transfected with PS80 PBCA NC/HRE-cmvBDNF than those without hypoxia. TrkB and phospho-Akt were also elevated which correlated with neural differentiation. The findings suggest that PS80 PBCA NC too can be endocytosed to serve as an efficient vector for genes coupled to the HRE in hypoxia-sensitive cells, and activation of the PI3/Akt pathway in iPSCs by BDNF is capable of neural lineage specification. PMID:28335495

  8. Effects of long-term risedronate treatment on serum ferritin levels in postmenopausal women with osteoporosis: the impact of cardiovascular risk factor load.

    Science.gov (United States)

    Feldbrin, Zeev; Luckish, Alla; Shargorodsky, Marina

    2016-01-01

    Although ferritin has been considered as a possible link between accelerated bone loss and atherosclerosis, the long-term impact of therapeutic agents widely used to treat osteoporosis, such as bisphosphonates, on ferritin levels has not been investigated. The present study investigated the effects of risedronate on serum ferritin levels in postmenopausal women with osteoporosis. In an open-label, prospective, uncontrolled study, 68 postmenopausal women with osteoporosis were evaluated. Study participants received risedronate orally at a dose of 35 mg/week during a 6-month treatment period. Blood sampling for lipid profile, hemoglobin A1c, insulin, fibrinogen, C-reactive protein, osteoprotegerin, and ferritin was performed at baseline and after 6 months of treatment. Pulse-wave velocity and augmentation index at baseline were determined using SphygmoCor version 7.1 (AtCor Medical, Sydney, Australia). Mean (SD) serum ferritin decreased significantly from 62.1 (44.8) to 46.7 (29.4) μg/dL (P serum ferritin levels in postmenopausal women with osteoporosis and cardiovascular risk factors.

  9. The economics of using prophylactic antibiotic-loaded bone cement in total knee replacement.

    Science.gov (United States)

    Gutowski, C J; Zmistowski, B M; Clyde, C T; Parvizi, J

    2014-01-01

    The rate of peri-prosthetic infection following total joint replacement continues to rise, and attempts to curb this trend have included the use of antibiotic-loaded bone cement at the time of primary surgery. We have investigated the clinical- and cost-effectiveness of the use of antibiotic-loaded cement for primary total knee replacement (TKR) by comparing the rate of infection in 3048 TKRs performed without loaded cement over a three-year period versus the incidence of infection after 4830 TKRs performed with tobramycin-loaded cement over a later period of time of a similar duration. In order to adjust for confounding factors, the rate of infection in 3347 and 4702 uncemented total hip replacements (THR) performed during the same time periods, respectively, was also examined. There were no significant differences in the characteristics of the patients in the different cohorts. The absolute rate of infection increased when antibiotic-loaded cement was used in TKR. However, this rate of increase was less than the rate of increase in infection following uncemented THR during the same period. If the rise in the rate of infection observed in THR were extrapolated to the TKR cohort, 18 additional cases of infection would have been expected to occur in the cohort receiving antibiotic-loaded cement, compared with the number observed. Depending on the type of antibiotic-loaded cement that is used, its cost in all primary TKRs ranges between USD $2112.72 and USD $112 606.67 per case of infection that is prevented.

  10. The DEMO wall load challenge

    Science.gov (United States)

    Wenninger, R.; Albanese, R.; Ambrosino, R.; Arbeiter, F.; Aubert, J.; Bachmann, C.; Barbato, L.; Barrett, T.; Beckers, M.; Biel, W.; Boccaccini, L.; Carralero, D.; Coster, D.; Eich, T.; Fasoli, A.; Federici, G.; Firdaouss, M.; Graves, J.; Horacek, J.; Kovari, M.; Lanthaler, S.; Loschiavo, V.; Lowry, C.; Lux, H.; Maddaluno, G.; Maviglia, F.; Mitteau, R.; Neu, R.; Pfefferle, D.; Schmid, K.; Siccinio, M.; Sieglin, B.; Silva, C.; Snicker, A.; Subba, F.; Varje, J.; Zohm, H.

    2017-04-01

    For several reasons the challenge to keep the loads to the first wall within engineering limits is substantially higher in DEMO compared to ITER. Therefore the pre-conceptual design development for DEMO that is currently ongoing in Europe needs to be based on load estimates that are derived employing the most recent plasma edge physics knowledge. An initial assessment of the static wall heat load limit in DEMO infers that the steady state peak heat flux limit on the majority of the DEMO first wall should not be assumed to be higher than 1.0 MW m-2. This compares to an average wall heat load of 0.29 MW m-2 for the design {\\tt {EU}}{\\tt {~}}{\\tt {DEMO1}}{\\tt {~2015}} assuming a perfect homogeneous distribution. The main part of this publication concentrates on the development of first DEMO estimates for charged particle, radiation, fast particle (all static) and disruption heat loads. Employing an initial engineering wall design with clear optimization potential in combination with parameters for the flat-top phase (x-point configuration), loads up to 7 MW m-2 (penalty factor for tolerances etc not applied) have been calculated. Assuming a fraction of power radiated from the x-point region between 1/5 and 1/3, peaks of the total power flux density due to radiation of 0.6-0.8 MW m-2 are found in the outer baffle region. This first review of wall loads, and the associated limits in DEMO clearly underlines a significant challenge that necessitates substantial engineering efforts as well as a considerable consolidation of the associated physics basis.

  11. Chapter 2--the spinal generation of phases and cycle duration.

    Science.gov (United States)

    Gossard, Jean-Pierre; Sirois, Jennifer; Noué, Patrick; Côté, Marie-Pascale; Ménard, Ariane; Leblond, Hugues; Frigon, Alain

    2011-01-01

    During walking, an increase in speed is accompanied by a decrease in the stance phase duration while the swing phase remains relatively invariant. By definition, the rhythm generator in the lumbar spinal cord controls cycle period, phase durations, and phase transitions. Our first aim was to determine if this asymmetry in the control of locomotor cycles is an inherent property of the central pattern generator (CPG). We recorded episodes of fictive locomotion, that is, locomotor patterns in absence of reafference, in decerebrate cats with or without a complete spinal transection (acute or chronic). In fictive locomotion, stance and swing phases typically correspond to extension and flexion, respectively. In the vast majority of locomotor episodes, cycle period varied more with extensor phase duration. This could be observed without phasic sensory feedback or supraspinal structures or pharmacology. In a few experiments, we stimulated the mesencephalic locomotor region or selected peripheral nerves during fictive locomotion and both could alter the phase/cycle period relationship. We conclude that there is a built-in asymmetry within the spinal rhythm generator for locomotion, which can be modified by extraneous factors. Locomotor and scratching rhythms are characterized by alternation of flexion and extension phases within one hindlimb, which are mediated by rhythm-generating circuitry within the spinal cord. Our second aim was to determine if rhythm generators for locomotion and scratch have similar control mechanisms in adult decerebrate cats. The regulation of cycle period during fictive scratching was evaluated, as were the effects of specific sensory inputs on phase durations and transitions during pinna-evoked fictive scratching. Results show that cycle period during fictive scratching varied predominantly with flexion phase duration, contrary to spontaneous fictive locomotion. Ankle dorsiflexion greatly increased extension phase duration and cycle period

  12. Short Sleep Duration by Occupation Group - 29 States, 2013-2014.

    Science.gov (United States)

    Shockey, Taylor M; Wheaton, Anne G

    2017-03-03

    The American Academy of Sleep Medicine and the Sleep Research Society have determined that adults require ≥7 hours of sleep per day to promote optimal health (1). Short sleep duration (sleep duration varies by characteristics such as race, education, marital status, obesity, and cigarette smoking (3). Work-related factors such as job stress, work hours, shift work, and physically demanding work have been found to be associated with sleep duration and quality (4-6). All of these work factors vary by industry and occupation of employment, and the prevalence of short sleep duration has been shown to vary by broad industry and occupation category (7). To provide updated and more detailed information about which occupation groups have the highest prevalences of short sleep duration, CDC analyzed data from currently employed adults surveyed for the 2013 and 2014 Behavioral Risk Factor Surveillance System (BRFSS) in 29 states. Among 22 major occupation groups, the highest prevalences of short sleep duration were among workers in the following five groups: Production (42.9%), Healthcare Support (40.1%), Healthcare Practitioners and Technical (40.0%), Food Preparation and Serving-Related (39.8%), and Protective Service (39.2%). The significant differences among occupation groups in the prevalence of short sleep duration suggest that work-related factors should be further evaluated as they might relate to sleep.

  13. Lightening the Load

    OpenAIRE

    Remington, Anna M.; Swettenham, John G.; Lavie, Nilli

    2012-01-01

    Autism spectrum disorder (ASD) research portrays a mixed picture of attentional abilities with demonstrations of enhancements (e.g., superior visual search) and deficits (e.g., higher distractibility). Here we test a potential resolution derived from the Load Theory of Attention (e.g., Lavie, 2005). In Load Theory, distractor processing depends on the perceptual load of the task and as such can only be eliminated under high load that engages full capacity. We hypothesize that ASD involves enh...

  14. Fluctuation behaviors of financial return volatility duration

    Science.gov (United States)

    Niu, Hongli; Wang, Jun; Lu, Yunfan

    2016-04-01

    It is of significantly crucial to understand the return volatility of financial markets because it helps to quantify the investment risk, optimize the portfolio, and provide a key input of option pricing models. The characteristics of isolated high volatility events above certain threshold in price fluctuations and the distributions of return intervals between these events arouse great interest in financial research. In the present work, we introduce a new concept of daily return volatility duration, which is defined as the shortest passage time when the future volatility intensity is above or below the current volatility intensity (without predefining a threshold). The statistical properties of the daily return volatility durations for seven representative stock indices from the world financial markets are investigated. Some useful and interesting empirical results of these volatility duration series about the probability distributions, memory effects and multifractal properties are obtained. These results also show that the proposed stock volatility series analysis is a meaningful and beneficial trial.

  15. [Labor duration: from normality to dystocia].

    Science.gov (United States)

    Kayem, G

    2015-04-01

    "Normal" labor has been surprisingly little studied in the past 60 years even though it is a central axis in obstetrics. Standards were proposed 60 years ago by Emmanuel Friedman and adopted by many countries to become then, driven from Dublin school, the conditions allowing the management of labor: rupture of membranes and oxytocin with, in case of failure for dynamic dystocia, cesarean. Recent data have suggested that labor duration had changed since the 1960s. Changes in women's characteristics and in obstetric practice especially with the widespread use of oxytocin and realization of epidural may have an impact on labor duration. Current studies suggest that it may be possible to authorize longer labor duration without significant increase in maternal or neonatal morbidity. However, it is premature to change practices following the latest American recommendations without prior studies. Copyright © 2015. Published by Elsevier SAS.

  16. Empirical Investigations of the Opportunity Limits of Automatic Residential Electric Load Shaping

    Energy Technology Data Exchange (ETDEWEB)

    Cruickshank, Robert F.; Henze, Gregor P.; Balaji, Rajagopalan; Hodge, Bri-Mathias S.; Florita, Anthony R.

    2017-05-11

    Residential electric load shaping is often modeled as infrequent, utility-initiated, short-duration deferral of peak demand through direct load control. In contrast, modeled herein is the potential for frequent, transactive, intraday, consumer-configurable load shaping for storage-capable thermostatically controlled electric loads (TCLs), including refrigerators, freezers, and hot water heaters. Unique to this study are 28 months of 15-minute-interval observations of usage in 101 homes in the Pacific Northwest United States that specify exact start, duration, and usage patterns of approximately 25 submetered loads per home. The magnitudes of the load shift from voluntarily-participating TCL appliances are aggregated to form hourly upper and lower load-shaping limits for the coordination of electrical generation, transmission, distribution, storage, and demand. Empirical data are statistically analyzed to define metrics that help quantify load-shaping opportunities.

  17. Empirical Investigations of the Opportunity Limits of Automatic Residential Electric Load Shaping: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Cruickshank, Robert F.; Henze, Gregor P.; Balaji, Rajagopalan; Hodge, Bri-Mathias S.; Florita, Anthony R.

    2017-04-01

    Residential electric load shaping is often modeled as infrequent, utility-initiated, short-duration deferral of peak demand through direct load control. In contrast, modeled herein is the potential for frequent, transactive, intraday, consumer-configurable load shaping for storage-capable thermostatically controlled electric loads (TCLs), including refrigerators, freezers, and hot water heaters. Unique to this study are 28 months of 15-minute-interval observations of usage in 101 homes in the Pacific Northwest United States that specify exact start, duration, and usage patterns of approximately 25 submetered loads per home. The magnitudes of the load shift from voluntarily-participating TCL appliances are aggregated to form hourly upper and lower load-shaping limits for the coordination of electrical generation, transmission, distribution, storage, and demand. Empirical data are statistically analyzed to define metrics that help quantify load-shaping opportunities.

  18. Slow Wave Sleep and Long Duration Spaceflight

    Science.gov (United States)

    Whitmire, Alexandra; Orr, Martin; Arias, Diana; Rueger, Melanie; Johnston, Smith; Leveton, Lauren

    2012-01-01

    While ground research has clearly shown that preserving adequate quantities of sleep is essential for optimal health and performance, changes in the progression, order and /or duration of specific stages of sleep is also associated with deleterious outcomes. As seen in Figure 1, in healthy individuals, REM and Non-REM sleep alternate cyclically, with stages of Non-REM sleep structured chronologically. In the early parts of the night, for instance, Non-REM stages 3 and 4 (Slow Wave Sleep, or SWS) last longer while REM sleep spans shorter; as night progresses, the length of SWS is reduced as REM sleep lengthens. This process allows for SWS to establish precedence , with increases in SWS seen when recovering from sleep deprivation. SWS is indeed regarded as the most restorative portion of sleep. During SWS, physiological activities such as hormone secretion, muscle recovery, and immune responses are underway, while neurological processes required for long term learning and memory consolidation, also occur. The structure and duration of specific sleep stages may vary independent of total sleep duration, and changes in the structure and duration have been shown to be associated with deleterious outcomes. Individuals with narcolepsy enter sleep through REM as opposed to stage 1 of NREM. Disrupting slow wave sleep for several consecutive nights without reducing total sleep duration or sleep efficiency is associated with decreased pain threshold, increased discomfort, fatigue, and the inflammatory flare response in skin. Depression has been shown to be associated with a reduction of slow wave sleep and increased REM sleep. Given research that shows deleterious outcomes are associated with changes in sleep structure, it is essential to characterize and mitigate not only total sleep duration, but also changes in sleep stages.

  19. Taking a Load Off.

    Science.gov (United States)

    Kenny, John

    1995-01-01

    Discusses the snow -load capacity of school roofs and how understanding this data aids in planning preventive measures and easing fear of roof collapse. Describes how to determine snow-load capacity, and explains the load-bearing behavior of flat versus sloped roofs. Collapse prevention measures are highlighted. (GR)

  20. Increase of the seasonal performance factor by means of a weather-controlled load loop; Verbesserung der Jahresarbeitszahl durch witterungsgefuehrten Ladekreis - Schlussbericht 2008

    Energy Technology Data Exchange (ETDEWEB)

    Hubacher, P. [Hubacher Engineering, Engelburg (Switzerland); Ehrbar, M. [Enertec AG, Sargans (Switzerland)

    2008-11-15

    Experience shows that the post condenser water temperature in particular for air-water heat pumps is much higher than the set temperature. This is not efficient and can be improved by setting the mass flow through the condenser via an ambient temperature sensor. In this way an optimal hydraulic and energetic decoupling of the sink and source systems is achieved, as well as a power optimised control of the condenser temperature. A model shows a COP improvement of 20% at higher ambient temperatures. The heat pump thus becomes a 'plug and play' unit harmonizing with the heating network. It then only needs to be thermodynamically matched to the heating system. The method performed perfectly in two installations, but also demonstrated that the correct conditions need to be met. In addition to a storage tank that remains vertically stratified in temperature under high mass flow condition, the control valve must operate quickly. The condenser must be dimensioned such that the pressure drop under the highest flow conditions stays within acceptable limits. Finally the storage tank ON and OFF sensors must be positioned allowing the maximum use of the stored capacity. The availability of the stored heat quantity is defined primarily by the mass flow rate in the heat distribution system and not by the store's thermal capacity. So in the case of a 1-hour down time (e.g. at lunch time), the tank volume needs to equal the water quantity which would flow through the heating system in 1 hour. This leads in practice to over dimensioned storage tanks. This can be countered by allowing a throttle valve to half the heated circuit flow when the heat pump is not operating. This increases the storage tanks reserve time by a factor of 2. However the average temperature between the feeder and return systems falls slightly and the amount of heat that can be transferred falls by about 30%. In the investigated installations the SPF increased by 11% (installation A) and 8

  1. Analysis models for variables associated with breastfeeding duration

    Directory of Open Access Journals (Sweden)

    Edson Theodoro dos S. Neto

    2013-09-01

    Full Text Available OBJECTIVE To analyze the factors associated with breastfeeding duration by two statistical models. METHODS A population-based cohort study was conducted with 86 mothers and newborns from two areas primary covered by the National Health System, with high rates of infant mortality in Vitória, Espírito Santo, Brazil. During 30 months, 67 (78% children and mothers were visited seven times at home by trained interviewers, who filled out survey forms. Data on food and sucking habits, socioeconomic and maternal characteristics were collected. Variables were analyzed by Cox regression models, considering duration of breastfeeding as the dependent variable, and logistic regression (dependent variables, was the presence of a breastfeeding child in different post-natal ages. RESULTS In the logistic regression model, the pacifier sucking (adjusted Odds Ratio: 3.4; 95%CI 1.2-9.55 and bottle feeding (adjusted Odds Ratio: 4.4; 95%CI 1.6-12.1 increased the chance of weaning a child before one year of age. Variables associated to breastfeeding duration in the Cox regression model were: pacifier sucking (adjusted Hazard Ratio 2.0; 95%CI 1.2-3.3 and bottle feeding (adjusted Hazard Ratio 2.0; 95%CI 1.2-3.5. However, protective factors (maternal age and family income differed between both models. CONCLUSIONS Risk and protective factors associated with cessation of breastfeeding may be analyzed by different models of statistical regression. Cox Regression Models are adequate to analyze such factors in longitudinal studies.

  2. Vocal Loading in Speaking a Foreign Language.

    Science.gov (United States)

    Järvinen, Kati; Laukkanen, Anne-Maria

    2015-01-01

    This study investigated whether speaking a foreign language affects the subjective notions of vocal fatigue, and whether acoustic measurements reveal a higher vocal loading. The speech samples of 20 native Finnish-speaking and 23 native English-speaking subjects were recorded in Finnish and in English. From the speech samples, fundamental frequency, equivalent sound level, total duration of voiced speech, speech rate, alpha ratio and L1-L0 level difference were analyzed. Vocal doses were calculated. According to subjective notions, the voice gets tired more quickly when speaking a foreign language. The mean fundamental frequency increased but the speech rate and total duration of voiced speech decreased significantly when speaking a foreign language. Thus, the vocal doses decreased. The subjective sensations of increased vocal fatigue may be due to increased mental stress rather than to higher vocal loading. However, a trend that speaking a foreign language may involve more loading was found in L1-L0 level difference and in the doses normalized to time dose. Longer speech samples should be studied. Voice quality-based indicators of vocal loading are worth testing in addition to the measures based on the amount of voicing in speech. © 2015 S. Karger AG, Basel.

  3. Relationship between sleep duration and Framingham cardiovascular risk score and prevalence of cardiovascular disease in Koreans.

    Science.gov (United States)

    Im, Eui; Kim, Gwang-Sil

    2017-09-01

    Studies have shown sleep duration to be related to the prevalence of metabolic syndrome and hypertension. However, whether sleep duration is associated with cardiovascular disease (CVD) risk and the prevalence of CVD irrespective of conventional CV-risk factor, such as diabetes mellitus, obesity, and metabolic syndrome, has not been well established for the Korean population.A total of 23,878 individuals aged 18 years or older from the 2007-2010 Korean National Health and Nutrition Examination Survey were analyzed. We evaluated the relationship between sleep duration and CV-event risk using the Framingham Cardiovascular Risk Score (FRS; ≥10% or ≥20%) and the prevalence of CVD.After adjusting for traditional risk factors of CVD, a short sleep duration (≤5 hours) yielded odds ratios (OR) of 1.344 (95% confidence interval [CI] 1.200-1.505) for intermediate to high risk and 1.357 (95% CI, 1.140-1.614) for high risk. A long sleep duration (≥9 hours) was also associated with both intermediate to high (OR 1.142, 95% CI 1.011-1.322) and high cardiovascular FRS (OR 1.276, 95% CI 1.118-1.457).Both short and long sleep durations were related with high CVD risk, irrespective of established CVD risk, and a short sleep duration was associated with a higher prevalence of CVD than an optimal or long sleep duration.

  4. Influence of Load Factors on Rutting of Asphalt Pavement on Large Longitudinal Slope%影响长大纵坡沥青路面车辙的荷载因素分析

    Institute of Scientific and Technical Information of China (English)

    王翼

    2014-01-01

    为了找到影响长大纵坡沥青路面车辙的最不利荷载因素,从交通荷载的角度提出车辙防治措施,对坡度、车速和超载对长大纵坡路面车辙的影响进行了计算分析和比较。研究表明,坡度对长大纵坡的路面车辙的影响较小;与坡度相比,较低的车速更易导致车辙病害的产生;车辆超载是导致车辙产生和进一步恶化的最不利因素。%To find out the critical load factor leading to rutting on large longitudinal slope and control measures,this paper analyzes the influence of slope,speed of vehicle and overload on rutting on the asphalt pavement on large longitudinal slope.The result indicates that the slope has limited influence on the rutting.There is a direct correlation between speed of vehicle and rutting.The overload is proved to be the critical factor leading to excessive pavement rutting on large longitudinal slope.

  5. Torsional Loadings of a Semi-Infinite Perfectly Conducting Elastic Half Space

    Directory of Open Access Journals (Sweden)

    K. S. Sarma

    1971-07-01

    Full Text Available The problem of torsional oscillations of a semi infinite perfectly conducting elastic medium with an applied magnetic filed normal to the boundary due to (i an impulsive load,(ii step load, and (iii sinusoidal load are solved. In the case of impulsive loading over a circular region, the duration of disturbance at a point is greater than in the case of a purely elastic materials. The width of distribution is the same in both the cases.

  6. Spatial electric load forecasting

    CERN Document Server

    Willis, H Lee

    2002-01-01

    Spatial Electric Load Forecasting Consumer Demand for Power and ReliabilityCoincidence and Load BehaviorLoad Curve and End-Use ModelingWeather and Electric LoadWeather Design Criteria and Forecast NormalizationSpatial Load Growth BehaviorSpatial Forecast Accuracy and Error MeasuresTrending MethodsSimulation Method: Basic ConceptsA Detailed Look at the Simulation MethodBasics of Computerized SimulationAnalytical Building Blocks for Spatial SimulationAdvanced Elements of Computerized SimulationHybrid Trending-Simulation MethodsAdvanced

  7. Liver iron and serum ferritin levels are misleading for estimating cardiac, pancreatic, splenic and total body iron load in thalassemia patients: factors influencing the heterogenic distribution of excess storage iron in organs as identified by MRI T2*.

    Science.gov (United States)

    Kolnagou, Annita; Natsiopoulos, Konstantinos; Kleanthous, Marios; Ioannou, Alexia; Kontoghiorghes, George J

    2013-01-01

    A comparative assessment of excess storage iron distribution in the liver, heart, spleen and pancreas of β-thalassemia major (β-ΤΜ) patients has been carried out using magnetic resonance imaging (MRI) relaxation times T2*. The β-ΤΜ patients (8-40 years, 11 males, 9 females) had variable serum ferritin levels (394-5603 μg/L) and were treated with deferoxamine (n = 10), deferiprone (n = 5) and deferoxamine/deferiprone combination (n = 5). MRI T2* assessment revealed that excess iron is not proportionally distributed among the organs but is stored at different concentrations in each organ and the distribution is different for each β-ΤΜ patient. There is random variation in the distribution of excess storage iron from normal to severe levels in each organ among the β-ΤΜ patients by comparison to the same organs of ten normal volunteers. The correlation of serum ferritin with T2* was for spleen (r = -0.81), liver (r = -0.63), pancreas (r = -0.33) and none with heart. Similar trend was observed in the correlation of liver T2* with the T2* of spleen (r = 0.62), pancreas (r = 0.61) and none with heart. These studies contradict previous assumptions that serum ferritin and liver iron concentration is proportional to the total body iron stores in β-ΤΜ and especially cardiac iron load. The random variation in the concentration of iron in the organs of β-ΤΜ patients appears to be related to the chelation protocol, organ function, genetic, dietary, pharmacological and other factors. Monitoring of the iron load for all the organs is recommended for each β-ΤΜ patient.

  8. Duration Properties of Timed Transition Systems

    DEFF Research Database (Denmark)

    Liu, Zhiming; Ravn, Anders P.; Li, Xiaoshan

    1997-01-01

    This paper proposes a method for formal real-time systems development.The system requirements and high level design decisions are time interval properties, and are therefore specified in the Duration Calculus (DC), while the implementation and refinement are described in termsof timed transition ...

  9. Preventive maintenance at opportunities of restricted duration

    NARCIS (Netherlands)

    R. Dekker (Rommert); E. Smeitink

    1994-01-01

    textabstractThis article deals with the problem of setting priorities for the execution of maintenance packages at randomly occurring opportunities. These opportunities are of restricted duration, implying that only a limited number of packages can be executed. The main idea proposed is to set up a

  10. 5 CFR 890.1302 - Duration.

    Science.gov (United States)

    2010-01-01

    ... Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES HEALTH BENEFITS PROGRAM Department of Defense Federal Employees Health Benefits Program Demonstration Project § 890.1302 Duration. The demonstration project will run from January 1, 2000, through...

  11. Verifying duration properties of timed transition systems

    DEFF Research Database (Denmark)

    Liu, Zhiming; Ravn, Anders P.; Li, Xiaoshan

    1998-01-01

    This paper proposes a method for formal real-time systems development:Requirements and high level design decisions are time interval properties and are therefore specified in the Duration Calculus (DC), while implementations are described bytimed transition systems (TTS). A link from implementati...

  12. Estimating the duration of speciation from phylogenies.

    Science.gov (United States)

    Etienne, Rampal S; Morlon, Hélène; Lambert, Amaury

    2014-08-01

    Speciation is not instantaneous but takes time. The protracted birth-death diversification model incorporates this fact and predicts the often observed slowdown of lineage accumulation toward the present. The mathematical complexity of the protracted speciation model has barred estimation of its parameters until recently a method to compute the likelihood of phylogenetic branching times under this model was outlined (Lambert et al. ). Here, we implement this method and study using simulated phylogenies of extant species how well we can estimate the model parameters (rate of initiation of speciation, rate of extinction of incipient and good species, and rate of completion of speciation) as well as the duration of speciation, which is a combination of the aforementioned parameters. We illustrate our approach by applying it to a primate phylogeny. The simulations show that phylogenies often do not contain enough information to provide unbiased estimates of the speciation-initiation rate and the extinction rate, but the duration of speciation can be estimated without much bias. The estimate of the duration of speciation for the primate clade is consistent with literature estimates. We conclude that phylogenies combined with the protracted speciation model provide a promising way to estimate the duration of speciation.

  13. Breathhold duration and response to marijuana smoke.

    Science.gov (United States)

    Zacny, J P; Chait, L D

    1989-06-01

    Marijuana smokers are frequently observed to hold the smoke in their lungs for prolonged periods (10-15 sec) apparently in the belief that prolonged breathholding intensifies the effects of the drug. The actual influence of breathhold duration on response to marijuana smoke has not been studied. The present study examined the effects of systematic manipulation of breathhold duration on the physiological, cognitive and subjective response to marijuana smoke in a group of eight regular marijuana smokers. Subjects were exposed to each of three breathhold duration conditions (0, 10 and 20 sec) on three occasions, scheduled according to a randomized block design. A controlled smoking procedure was used in which the number of puffs, puff volume and postpuff inhalation volume were held constant. Expired air carbon monoxide levels were measured before and after smoking to monitor smoke intake. Typical marijuana effects (increased heart rate, increased ratings of "high" and impaired memory performance) were observed under each of the breathhold conditions, but there was little evidence that response to marijuana was a function of breathhold duration.

  14. Sickness induced by head movements after different centrifugal Gx-loads and durations

    NARCIS (Netherlands)

    Nooij, S.A.E.; Bos, J.E.

    2007-01-01

    Het misselijk worden na centrifugeren lijkt verdacht veel op de misselijkheid die astronauten in de ruimte kunnen ervaren. Hoofdbewegingen, G-belasting en -duur spelen daarbij een hier nader bepaalde rol.

  15. The effect of insulin-loaded linear poly(ethylene glycol-brush-like poly(L-lysine block copolymer on renal ischemia/reperfusion-induced lung injury through downregulating hypoxia-inducible factor

    Directory of Open Access Journals (Sweden)

    Tong F

    2016-04-01

    Full Text Available Fei Tong, Xiangyuan Tang, Xin Li, Wenquan Xia, Daojun Liu Department of Chemistry, Medical College, Shantou University, Shantou, People’s Republic of China Abstract: The aim of this study was to observe the therapeutic effect of insulin-loaded linear poly(ethylene glycol-brush-like poly(L-lysine block copolymer poly(ethylene glycol-b-(poly(ethylenediamine L-glutamate-g-poly(L-lysine (PEG-b-(PELG-g-PLL on renal ischemia/reperfusion-induced lung injury through downregulating hypoxia-inducible factor (HIF as compared to free insulin. Sprague Dawley rats were pretreated with 30 U/kg insulin or insulin/PEG-b-(PELG-g-PLL complex, and then subjected to 45 minutes of ischemia and 24 hours of reperfusion. The blood and lungs were collected, the level of serum creatinine and blood urea nitrogen were measured, and the dry/wet lung ratios, the activity of superoxide dismutase and myeloperoxidase, the content of methane dicarboxylic aldehyde and tumor necrosis factor-α, and the expression of HIF-1α and vascular endothelial growth factor (VEGF were measured in pulmonary tissues. Both insulin and insulin/PEG-b-(PELG-g-PLL preconditioning improved the recovery of renal function, reduced pulmonary oxidative stress injury, restrained inflammatory damage, and downregulated the expression of HIF-1α and VEGF as compared to ischemia/reperfusion group, while insulin/PEG-b-(PELG-g-PLL significantly improved this effect. Keywords: insulin, block copolymer, RI/RILI, HIF-1α, VEGF

  16. Comparison of Deterministic and Probabilistic Radial Distribution Systems Load Flow

    Science.gov (United States)

    Gupta, Atma Ram; Kumar, Ashwani

    2017-08-01

    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.

  17. Chronotype and sleep duration: the influence of season of assessment.

    Science.gov (United States)

    Allebrandt, Karla V; Teder-Laving, Maris; Kantermann, Thomas; Peters, Annette; Campbell, Harry; Rudan, Igor; Wilson, James F; Metspalu, Andres; Roenneberg, Till

    2014-06-01

    between the mid sleep on free and work days - which varied with age and sex) contributed to a greater extent to the variation in sleep duration than chronotype (after taking into account factors that are known to influence sleep duration, i.e. age, sex and body mass index). Variation in chronotype was also dependent on age, sex, season of assessment and SJl (which is highly correlated with chronotype - SJl was larger among later chronotypes). In summary, subjective assessments of sleep/wake times are very reliable to assess internal time and sleep duration (e.g. reproducing sleep duration and timing tendencies related to age and sex across the investigated populations), but season of assessment should be regarded as a potential confounder. We identified in this study photoperiod (seasonal adaptation) and SJl as two main factors influencing seasonal variation in chronotype and sleep duration. In conclusion, season of assessment, sex and age have an effect on epidemiological variation in sleep duration, chronotype and SJl, and should be included in studies investigating associations between these phenotypes and health parameters, and on the development of optimal prevention strategies.

  18. Optimisation of load control

    Energy Technology Data Exchange (ETDEWEB)

    Koponen, P. [VTT Energy, Espoo (Finland)

    1998-08-01

    Electricity cannot be stored in large quantities. That is why the electricity supply and consumption are always almost equal in large power supply systems. If this balance were disturbed beyond stability, the system or a part of it would collapse until a new stable equilibrium is reached. The balance between supply and consumption is mainly maintained by controlling the power production, but also the electricity consumption or, in other words, the load is controlled. Controlling the load of the power supply system is important, if easily controllable power production capacity is limited. Temporary shortage of ca