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Sample records for cycle intermittent compared

  1. Randomized, controlled trial comparing synchronized intermittent mandatory ventilation and synchronized intermittent mandatory ventilation plus pressure support in preterm infants.

    Science.gov (United States)

    Reyes, Zenaida C; Claure, Nelson; Tauscher, Markus K; D'Ugard, Carmen; Vanbuskirk, Silvia; Bancalari, Eduardo

    2006-10-01

    Prolonged mechanical ventilation is associated with lung injury in preterm infants. In these infants, weaning from synchronized intermittent mandatory ventilation may be delayed by their inability to cope with increased respiratory loads. The addition of pressure support to synchronized intermittent mandatory ventilation can offset these loads and may facilitate weaning. The purpose of this work was to compare synchronized intermittent mandatory ventilation and synchronized intermittent mandatory ventilation plus pressure support in weaning from mechanical ventilation and the duration of supplemental oxygen dependency in preterm infants with respiratory failure. Preterm infants weighing 500 to 1000 g at birth who required mechanical ventilation during the first postnatal week were randomly assigned to synchronized intermittent mandatory ventilation or synchronized intermittent mandatory ventilation plus pressure support. In both groups, weaning followed a set protocol during the first 28 days. Outcomes were assessed during the first 28 days and until discharge or death. There were 107 infants enrolled (53 synchronized intermittent mandatory ventilation plus pressure support and 54 synchronized intermittent mandatory ventilation). Demographic and perinatal data, mortality, and morbidity did not differ between groups. During the first 28 days, infants in the synchronized intermittent mandatory ventilation plus pressure support group reached minimal ventilator settings and were extubated earlier than infants in the synchronized intermittent mandatory ventilation group. Total duration of mechanical ventilation, duration of oxygen dependency, and oxygen need at 36 weeks' postmenstrual age alone or combined with death did not differ between groups. However, infants in synchronized intermittent mandatory ventilation plus pressure support within the 700- to 1000-g birth weight strata had a shorter oxygen dependency. The results of this study suggest that the addition of

  2. Economic intermittency in a two-country model of business cycles coupled by investment

    International Nuclear Information System (INIS)

    Saiki, Y.; Chian, A.C.L.; Yoshida, H.

    2011-01-01

    Highlights: → Intermittent economic behavior of Keynes-Goodwin type model is investigated. → After a transition the system keeps its memory before the transition. → The intermittent phenomena is examined from the business cycle patterns. → It is concluded that dynamical patterns do not alter much around the transition. - Abstract: Intermittent behavior of economic dynamics is investigated by a two-country model of Keynes-Goodwin type business cycles. Numerical simulations show that after an economic system evolves from weak chaos to strong chaos the system keeps its memory before the transition and its time series alternates episodically between periods of weakly and strongly chaotic fluctuations. In addition, we examine the intermittent phenomena from the view point of business cycle patterns near the crisis point.

  3. Economic intermittency in a two-country model of business cycles coupled by investment

    Energy Technology Data Exchange (ETDEWEB)

    Saiki, Y., E-mail: saiki@math.sci.hokudai.ac.jp [Department of Mathematics, Hokkaido University, Sapporo 060-0810 (Japan); Chian, A.C.L. [National Institute for Space Research (INPE) and World Institute for Space Environment Research (WISER), P.O. Box 515, Sao Jose dos Campos-SP 12227-010 (Brazil); California Institute of Technology, Pasadena, CA 91125 (United States); Yoshida, H. [College of Economics, Nihon University, Tokyo 101-8360 (Japan)

    2011-06-15

    Highlights: > Intermittent economic behavior of Keynes-Goodwin type model is investigated. > After a transition the system keeps its memory before the transition. > The intermittent phenomena is examined from the business cycle patterns. > It is concluded that dynamical patterns do not alter much around the transition. - Abstract: Intermittent behavior of economic dynamics is investigated by a two-country model of Keynes-Goodwin type business cycles. Numerical simulations show that after an economic system evolves from weak chaos to strong chaos the system keeps its memory before the transition and its time series alternates episodically between periods of weakly and strongly chaotic fluctuations. In addition, we examine the intermittent phenomena from the view point of business cycle patterns near the crisis point.

  4. The reliability and validity of fatigue measures during short-duration maximal-intensity intermittent cycling.

    Science.gov (United States)

    Glaister, Mark; Stone, Michael H; Stewart, Andrew M; Hughes, Michael; Moir, Gavin L

    2004-08-01

    The purpose of the present study was to assess the reliability and validity of fatigue measures, as derived from 4 separate formulae, during tests of repeat sprint ability. On separate days over a 3-week period, 2 groups of 7 recreationally active men completed 6 trials of 1 of 2 maximal (20 x 5 seconds) intermittent cycling tests with contrasting recovery periods (10 or 30 seconds). All trials were conducted on a friction-braked cycle ergometer, and fatigue scores were derived from measures of mean power output for each sprint. Apart from formula 1, which calculated fatigue from the percentage difference in mean power output between the first and last sprint, all remaining formulae produced fatigue scores that showed a reasonably good level of test-retest reliability in both intermittent test protocols (intraclass correlation range: 0.78-0.86; 95% likely range of true values: 0.54-0.97). Although between-protocol differences in the magnitude of the fatigue scores suggested good construct validity, within-protocol differences highlighted limitations with each formula. Overall, the results support the use of the percentage decrement score as the most valid and reliable measure of fatigue during brief maximal intermittent work.

  5. A meta-analysis comparing efficacy of continuous terbinafine with intermittent itraconazole for toenail onychomycosis

    Directory of Open Access Journals (Sweden)

    Trivedi N

    2010-01-01

    Full Text Available Background: Toenail onychomycosis is a challenge for clinicians to treat. While both Itraconazole and terbinafine have proven to be effective against onychomycosis, very little is known about their comparative efficacy in achieving mycological and clinical cure. Aim: The purpose of this meta-analysis is to compare the efficacy of continuous terbinafine with intermittent itraconazole in the treatment of toenail onychomycosis. Material and Methods: all RCTs comparing continuous terbinafine with intermittent itraconazole were identified from PUBMED and BIDS electronic database. Results: analysis of total eight trials including 1181 patients state that treatment with continuous terbinafine is more likely to produce mycological and clinical cure compared to intermittent itraconazole with odds ratio 2.3(95% CI, 1.7 to 3.0 P< 0.0001 Conclusion: though both itraconazole and terbinafine are well tolerated and highly effective drugs, continuous terbinafine is more effective than intermittent itraconazole at achieving mycological cure of toenail onychomycosis

  6. Comparing microbial water quality in an intermittent and continuous piped water supply.

    Science.gov (United States)

    Kumpel, Emily; Nelson, Kara L

    2013-09-15

    Supplying piped water intermittently is a common practice throughout the world that increases the risk of microbial contamination through multiple mechanisms. Converting an intermittent supply to a continuous supply has the potential to improve the quality of water delivered to consumers. To understand the effects of this upgrade on water quality, we tested samples from reservoirs, consumer taps, and drinking water provided by households (e.g. from storage containers) from an intermittent and continuous supply in Hubli-Dharwad, India, over one year. Water samples were tested for total coliform, Escherichia coli, turbidity, free chlorine, and combined chlorine. While water quality was similar at service reservoirs supplying the continuous and intermittent sections of the network, indicator bacteria were detected more frequently and at higher concentrations in samples from taps supplied intermittently compared to those supplied continuously (p supply, with 0.7% of tap samples positive compared to 31.7% of intermittent water supply tap samples positive for E. coli. In samples from both continuously and intermittently supplied taps, higher concentrations of total coliform were measured after rainfall events. While source water quality declined slightly during the rainy season, only tap water from intermittent supply had significantly more indicator bacteria throughout the rainy season compared to the dry season. Drinking water samples provided by households in both continuous and intermittent supplies had higher concentrations of indicator bacteria than samples collected directly from taps. Most households with continuous supply continued to store water for drinking, resulting in re-contamination, which may reduce the benefits to water quality of converting to continuous supply. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Intermittent Stem Cell Cycling Balances Self-Renewal and Senescence of the C. elegans Germ Line.

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    Amanda Cinquin

    2016-04-01

    Full Text Available Self-renewing organs often experience a decline in function in the course of aging. It is unclear whether chronological age or external factors control this decline, or whether it is driven by stem cell self-renewal-for example, because cycling cells exhaust their replicative capacity and become senescent. Here we assay the relationship between stem cell cycling and senescence in the Caenorhabditis elegans reproductive system, defining this senescence as the progressive decline in "reproductive capacity," i.e. in the number of progeny that can be produced until cessation of reproduction. We show that stem cell cycling diminishes remaining reproductive capacity, at least in part through the DNA damage response. Paradoxically, gonads kept under conditions that preclude reproduction keep cycling and producing cells that undergo apoptosis or are laid as unfertilized gametes, thus squandering reproductive capacity. We show that continued activity is in fact beneficial inasmuch as gonads that are active when reproduction is initiated have more sustained early progeny production. Intriguingly, continued cycling is intermittent-gonads switch between active and dormant states-and in all likelihood stochastic. Other organs face tradeoffs whereby stem cell cycling has the beneficial effect of providing freshly-differentiated cells and the detrimental effect of increasing the likelihood of cancer or senescence; stochastic stem cell cycling may allow for a subset of cells to preserve proliferative potential in old age, which may implement a strategy to deal with uncertainty as to the total amount of proliferation to be undergone over an organism's lifespan.

  8. Hydrologic cycle and dynamics of aquatic macrophytes in two intermittent rivers of the semi-arid region of Brazil

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    F. Pedro

    Full Text Available The dynamics of aquatic macrophytes in intermittent rivers is generally related to the characteristics of the resistance and resilience of plants to hydrologic disturbances of flood and drought. In the semi-arid region of Brazil, intermittent rivers and streams are affected by disturbances with variable intensity, frequency, and duration throughout their hydrologic cycles. The aim of the present study is to determine the occurrence and variation of biomass of aquatic macrophyte species in two intermittent rivers of distinct hydrologic regimes. Their dynamics were determined with respect to resistance and resilience responses of macrophytes to flood and drought events by estimating the variation of biomass and productivity throughout two hydrologic cycles. Twenty-one visits were undertaken in the rewetting, drying, and drought phases in a permanent puddle in the Avelós stream and two temporary puddles in the Taperoá river, state of Paraíba, Northeast Brazil. The sampling was carried out by using the square method. Floods of different magnitudes occurred during the present study in the river and in the stream. The results showed that floods and droughts are determining factors in the occurrence of macrophytes and in the structure of their aquatic communities. The species richness of the aquatic macrophyte communities was lower in the puddles of the river and stream subject to flood events, when compared to areas where the run-off water is retained. At the beginning of the recolonization process, the intensity of the floods was decisive in the productivity and biomass of the aquatic macrophytes in the Taperoá river and the Avelós stream. In intermediate levels of disturbance, the largest values of productivity and biomass and the shortest time for starting the recolonization process occurred.

  9. Intermittent Solar Ammonia Absorption Cycle (ISAAC) refrigeration for lesser developed countries

    Science.gov (United States)

    Erickson, Donald C.

    1990-02-01

    The Intermittent Solar Ammonia Absorption Cycle (ISAAC) refrigerator is a solar thermal technology which provides low cost, efficient, reliable ice-making to areas without ready access to electricity. An ISAAC refrigeration system consists of a compound parabolic solar collector, two pressure vessels, a condenser, a cold box or refrigerated space, and simple connective piping -- no moving parts or electrical components. Most parts are simple construction or plumbing grade materials, locally available in many remote areas. This technology has numerous potential benefits in lesser developed countries both by providing a cheap, reliable source of ice, and, since manufacture requires only semi-skilled labor, a source of employment to the local economy. Applications include vaccine storage for health care clinics; fish, meat, and dairy product storage; and personal consumption. Importantly, this technology increases the quality of life for people in lesser developed countries without depleting fossil fuel resources or increasing the release of greenhouse gases such as CO2 and chlorofluorocarbons.

  10. Towards an intermittency-friendly energy system: Comparing electric boilers and heat pumps in distributed cogeneration

    International Nuclear Information System (INIS)

    Blarke, Morten B.

    2012-01-01

    Highlights: ► We propose an “intermittency-friendly” energy system design. ► We compare intermittency-friendly concepts in distributed cogeneration. ► We investigate a new concept involving a heat pump and intermediate cold storage. ► We find significant improvements in operational intermittency-friendliness. ► Well-designed heat pump concepts are more cost-effective than electric boilers. -- Abstract: Distributed cogeneration has played a key role in the implementation of sustainable energy policies for three decades. However, increasing penetration levels of intermittent renewables is challenging that position. The paradigmatic case of West Denmark indicates that distributed operators are capitulating as wind power penetration levels are moving above 25%; some operators are retiring cogeneration units entirely, while other operators are making way for heat-only boilers. This development is jeopardizing the system-wide energy, economic, and environmental benefits that distributed cogeneration still has to offer. The solution is for distributed operators to adapt their technology and operational strategies to achieve a better co-existence between cogeneration and wind power. Four options for doing so are analysed including a new concept that integrates a high pressure compression heat pump using low-temperature heat recovered from flue gasses in combination with an intermediate cold storage, which enables the independent operation of heat pump and cogenerator. It is found that an electric boiler provides consistent improvements in the intermittency-friendliness of distributed cogeneration. However, well-designed heat pump concepts are more cost-effective than electric boilers, and in future markets where the gas/electricity price ratio is likely to increase, compression heat pumps in combination with intermediate thermal storages represent a superior potential for combining an intermittency-friendly pattern of operation with the efficient use of

  11. Intermittent compared to continuous real-time fMRI neurofeedback boosts control over amygdala activation.

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    Hellrung, Lydia; Dietrich, Anja; Hollmann, Maurice; Pleger, Burkhard; Kalberlah, Christian; Roggenhofer, Elisabeth; Villringer, Arno; Horstmann, Annette

    2018-02-01

    Real-time fMRI neurofeedback is a feasible tool to learn the volitional regulation of brain activity. So far, most studies provide continuous feedback information that is presented upon every volume acquisition. Although this maximizes the temporal resolution of feedback information, it may be accompanied by some disadvantages. Participants can be distracted from the regulation task due to (1) the intrinsic delay of the hemodynamic response and associated feedback and (2) limited cognitive resources available to simultaneously evaluate feedback information and stay engaged with the task. Here, we systematically investigate differences between groups presented with different variants of feedback (continuous vs. intermittent) and a control group receiving no feedback on their ability to regulate amygdala activity using positive memories and feelings. In contrast to the feedback groups, no learning effect was observed in the group without any feedback presentation. The group receiving intermittent feedback exhibited better amygdala regulation performance when compared with the group receiving continuous feedback. Behavioural measurements show that these effects were reflected in differences in task engagement. Overall, we not only demonstrate that the presentation of feedback is a prerequisite to learn volitional control of amygdala activity but also that intermittent feedback is superior to continuous feedback presentation. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Comparing the Life Cycle Energy Consumption, Global ...

    Science.gov (United States)

    Managing the water-energy-nutrient nexus for the built environment requires, in part, a full system analysis of energy consumption, global warming and eutrophication potentials of municipal water services. As an example, we evaluated the life cycle energy use, greenhouse gas (GHG) emissions and aqueous nutrient releases of the whole anthropogenic municipal water cycle starting from raw water extraction to wastewater treatment and reuse/discharge for five municipal water and wastewater systems. The assessed options included conventional centralized services and four alternative options following the principles of source-separation and water fit-for-purpose. The comparative life cycle assessment identified that centralized drinking water supply coupled with blackwater energy recovery and on-site greywater treatment and reuse was the most energyand carbon-efficient water service system evaluated, while the conventional (drinking water and sewerage) centralized system ranked as the most energy- and carbon-intensive system. The electricity generated from blackwater and food residuals co-digestion was estimated to offset at least 40% of life cycle energy consumption for water/waste services. The dry composting toilet option demonstrated the lowest life cycle eutrophication potential. The nutrients in wastewater effluent are the dominating contributors for the eutrophication potential for the assessed system configurations. Among the parameters for which variability

  13. Double blind, randomised study of continuous terbinafine compared with intermittent itraconazole in treatment of toenail onychomycosis

    Science.gov (United States)

    Evans, E Glyn V; Sigurgeirsson, Bárdur

    1999-01-01

    Objective To compare the efficacy and safety of continuous terbinafine with intermittent itraconazole in the treatment of toenail onychomycosis. Design Prospective, randomised, double blind, double dummy, multicentre, parallel group study lasting 72 weeks. Setting 35 centres in six European countries. Subjects 496 patients aged 18 to 75 years with a clinical and mycological diagnosis of dermatophyte onychomycosis of the toenail. Interventions Study patients were randomly divided into four parallel groups to receive either terbinafine 250 mg a day for 12 or 16 weeks (groups T12 and T16) or itraconazole 400 mg a day for 1 week in every 4 weeks for 12 or 16 weeks (groups I3 and I4). Main outcome measures Assessment of primary efficacy at week 72 was mycological cure, defined as negative results on microscopy and culture of samples from the target toenail. Results At week 72 the mycological cure rates were 75.7% (81/107) in the T12 group and 80.8% (80/99) in the T16 group compared with 38.3% (41/107) in the I3 group and 49.1 % (53/108) in the I4 group. All comparisons (T12 v I3, T12 v I4, T16 v I3, T16 v I4) showed significantly higher cure rates in the terbinafine groups (all Pterbinafine at week 72. There were no differences in the number or type of adverse events recorded in the terbinafine or itraconazole groups. Conclusion Continuous terbinafine is significantly more effective than intermittent itraconazole in the treatment of patients with toenail onychomycosis. Key messagesGiven a correct diagnosis, fungal nail disease (onychomycosis) is curableTerbinafine is an allylamine antifungal with a primarily fungicidal mode of actionContinuous terbinafine treatment over 12 or 16 weeks achieves higher rates of clinical and mycological cure than intermittent itraconazole given over the same periodsTerbinafine is safe and well tolerated over 12 or 16 weeks of continuous treatmentContinuous terbinafine should be the current treatment of choice for onychomycosis PMID

  14. Comparative measurements of exodeviations in the three types of intermittent exotropia

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    Hong Wang

    2014-12-01

    Full Text Available AIM: To compare the results of 4 methods for measuring angle of exodeviation in the three types of intermittent exotropia, including when looking at indoor distance target of 6m, looking at indoor distance target of 30m, looking at outdoor far distance target, after 1h diagnostic occlusion test. METHODS: Prospective case series study. Sixty-five patients with intermittent exotropia between June 2013 and June 2014 were enrolled in the Department of Ophthalmology, Affiliated Hospital to Qingdao University, included 37 males and 28 females with average age(12.5±6.2years. All the patients were measured when looking at indoor distance target of 6m, looking at indoor distance target of 30m, looking at outdoor far distance target, after 1h diagnostic occlusion test. Intermittent exotropia was divided into basic type, convergence insufficiency type and divergence excess type, which was based on the different result of between the distance and near measurements. The One-way test was applied to analyze the four methods of measuring angle of exodeviation in the three types of intermittent exotropia. LSD-t test was applied to compare the differences between each two methods in each type.RESULTS: The distance exodeviations tested with looking at indoor distance target of 6m, looking at indoor distance target of 30m, looking at outdoor far distance target, after 1h diagnostic occlusion test were basic type(45.4±21.0, 55.0±15.0, 64.68±17.7, 68.75±16.6PD, convergence insufficiency type(33.3±14.0, 44.9±12.9, 43.6±11.8, 54.6±11.2PD, divergence excess type(55.6±17.4, 66.3±18.8, 76.9±16.4, 78.1±15.6PD. There were obviously differences between each two methods in each type(basic type F=9.649, P=0.00; convergence insufficiency type F=6.886, P=0.001; divergence excess type F=7.989, P=0.00. Compared with looking at indoor distance target of 30m, looking at outdoor far distance target(basic type P=0.044, divergence excess type P=0.048and after 1h diagnostic

  15. Comparative analysis of Goodwin's business cycle models

    Science.gov (United States)

    Antonova, A. O.; Reznik, S.; Todorov, M. D.

    2016-10-01

    We compare the behavior of solutions of Goodwin's business cycle equation in the form of neutral delay differential equation with fixed delay (NDDE model) and in the form of the differential equations of 3rd, 4th and 5th orders (ODE model's). Such ODE model's (Taylor series expansion of NDDE in powers of θ) are proposed in N. Dharmaraj and K. Vela Velupillai [6] for investigation of the short periodic sawthooth oscillations in NDDE. We show that the ODE's of 3rd, 4th and 5th order may approximate the asymptotic behavior of only main Goodwin's mode, but not the sawthooth modes. If the order of the Taylor series expansion exceeds 5, then the approximate ODE becomes unstable independently of time lag θ.

  16. The effect of 10 days of intermittent fasting on Wingate anaerobic power and prolonged high-intensity time-to-exhaustion cycling performance.

    Science.gov (United States)

    Naharudin, Mohamed Nashrudin Bin; Yusof, Ashril

    2018-06-01

    Many physically active individuals have undertaken intermittent fasting to reduce their daily caloric intake. However, abstaining from meals for a specific length of time may lead to the acute disturbance of highly carbohydrate-dependent exercise performance. The purpose of this study was to observe the effect of 10 days of intermittent fasting on high-intensity type exercises, Wingate anaerobic (WT) and prolonged high-intensity time-to-exhaustion (HIT) cycling test. Twenty participants were randomised into an intermittent fasting (FAS) and a control group (CON). One day after baseline data collection on Day-0 where participants consumed their recommended daily caloric intake (FAS = 2500 ± 143 kcal day -1 ; CON = 2492 ± 20 kcal day -1 ) served over a course of five meals, the FAS group consumed only four meals where 40% was restricted by the omission of lunch (FAS = 1500 ± 55 kcal day -1 ). This diet was then continued for 10 days. Data on exercise performance and other dependent variables were collected on Day-2, -4, -6, -8 and -10. A reduction in WT power in the FAS group was observed on Day-2 (821.74 ± 66.07 W) compared to Day-0 (847.63 ± 95.94 W) with a moderate effect size (p < .05, ES = 0.4), while HIT time-to-exhaustion performance declined over the 10 days with a trend of recovery from a large to a minimum effect size (p < .05, ES = 0.8-0.3). Body weight and triglyceride were consistently reduced in the FAS group (p < .01). The present study suggests that intermittent fasting must exceed 10 days to ensure that high-intensity performance does not deteriorate because this length of time seems to be required for effective adaptation to the new dietary regimen.

  17. Compared to Intermittant Claudication Critical Limb Ischemia Is Associated with Elevated Levels of Cytokines.

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    Juho Jalkanen

    Full Text Available Critical limb ischemia (CLI is the advanced stage of peripheral artery disease (PAD and associated with an extremely poor clinical outcome. In order to understand the possible role of circulating cytokines and poor outcome associated with CLI we compared the circulating cytokine profile of patients with CLI against patients with intermittent claudication (IC. The levels of 48 circulating cytokines were examined in 226 consecutive patients with peripheral artery disease (PAD admitted for elective, non-urgent, invasive treatment of IC or CLI. The PAD patient cohort was evenly distributed between subjects with IC (46.5% and CLI (53.5%. As accustomed in PAD, CLI was associated with higher age, chronic kidney disease and diabetes when compared to IC (P < 0.01 for all. In multivariable linear regression modeling taking into account the baseline differences between IC and CLI groups CLI was independently associated with elevated levels of a large number of cytokines: IL-1β, IL-1ra, IL-2Rα, IL-4, IL-6, IL-10, IFN-γ, GM-CSF, G-CSF (P < 0.01 for all, and IL-2, IL-7, IL-12, IL-13, IL-17, bFGF, VEGF, SCGF-β (P < 0.05 for all. The current findings indicate that CLI is associated with a circulating cytokine profile, which resembles serious medical conditions such as severe pancreatitis, sepsis, or even cancer. Compared to IC, CLI is a systemic inflammatory condition, which may explain the extremely poor outcome associated with it.

  18. Extended vs. brief intermittent access to palatable food differently promote binge-like intake, rejection of less preferred food, and weight cycling in female rats.

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    Kreisler, A D; Garcia, M G; Spierling, S R; Hui, B E; Zorrilla, E P

    2017-08-01

    Palatable food access promotes obesity leading some to diet. Here, we modeled the roles of duration, intermittency and choice of access in bingeing, escalation of daily intake, and underacceptance of alternatives. Female rats with ("Choice") or without continuous chow access, received chow or continuous (Chocolate), intermittent (MWF) long (24h, Int-Long), or intermittent short (30min, Int-Short) access to a sucrose-rich, chocolate-flavored diet (CHOC). Int-Long rats showed cycling body weight; they overate CHOC, had increased feed efficiency on access days and underate chow and lost weight on non-access days, the latter correlating with their reduced brown fat. Int-Short rats had the greatest 30-min intake upon CHOC access, but did not underaccept chow or weight cycle. Individual vulnerability for intermittent access-induced feeding adaptations was seen. Continuous access rats gained fat disproportionate, but in direct relation, to their normalized energy intake and persistently underaccepted chow despite abstinence and return to normal weight. Abstinence reduced the binge-like CHOC intake of Int-Short rats and increased that of continuous access rats, but not to levels associated with intermittent access history. Choice increased daily CHOC intake under Continuous access and binge-like intake under Int-Short access. Intermittency and duration of past access to palatable food have dissociable, individually-vulnerable influences on its intake and that of alternatives. With extended access, daily intake reflects the palatability of available food, rather than metabolic need. Ongoing restrictedness of access or a history of intermittency each drive binge-like intake. Aspects of palatable food availability, similar and different to drug availability, promote disordered eating. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. An intermittent control model of flexible human gait using a stable manifold of saddle-type unstable limit cycle dynamics.

    Science.gov (United States)

    Fu, Chunjiang; Suzuki, Yasuyuki; Kiyono, Ken; Morasso, Pietro; Nomura, Taishin

    2014-12-06

    Stability of human gait is the ability to maintain upright posture during walking against external perturbations. It is a complex process determined by a number of cross-related factors, including gait trajectory, joint impedance and neural control strategies. Here, we consider a control strategy that can achieve stable steady-state periodic gait while maintaining joint flexibility with the lowest possible joint impedance. To this end, we carried out a simulation study of a heel-toe footed biped model with hip, knee and ankle joints and a heavy head-arms-trunk element, working in the sagittal plane. For simplicity, the model assumes a periodic desired joint angle trajectory and joint torques generated by a set of feed-forward and proportional-derivative feedback controllers, whereby the joint impedance is parametrized by the feedback gains. We could show that a desired steady-state gait accompanied by the desired joint angle trajectory can be established as a stable limit cycle (LC) for the feedback controller with an appropriate set of large feedback gains. Moreover, as the feedback gains are decreased for lowering the joint stiffness, stability of the LC is lost only in a few dimensions, while leaving the remaining large number of dimensions quite stable: this means that the LC becomes saddle-type, with a low-dimensional unstable manifold and a high-dimensional stable manifold. Remarkably, the unstable manifold remains of low dimensionality even when the feedback gains are decreased far below the instability point. We then developed an intermittent neural feedback controller that is activated only for short periods of time at an optimal phase of each gait stride. We characterized the robustness of this design by showing that it can better stabilize the unstable LC with small feedback gains, leading to a flexible gait, and in particular we demonstrated that such an intermittent controller performs better if it drives the state point to the stable manifold, rather

  20. Comparative myoanatomy of cycliophoran life cycle stages

    DEFF Research Database (Denmark)

    Neves, Ricardo C.; Cunha, Maria R.; Funch, Peter

    2010-01-01

    The metazoan phylum Cycliophora includes small cryptic epibionts that live attached to the mouthparts of clawed lobsters. The life cycle is complex, with alternating sexual and asexual generations, and involves several sessile and free-living stages. So far, the morphological and genetic characte......The metazoan phylum Cycliophora includes small cryptic epibionts that live attached to the mouthparts of clawed lobsters. The life cycle is complex, with alternating sexual and asexual generations, and involves several sessile and free-living stages. So far, the morphological and genetic...

  1. Comparing technological hype cycles: Towards a theory

    NARCIS (Netherlands)

    Lente, H. van; Spitters, C.; Peine, A.

    2013-01-01

    The notion of ‘hype’ iswidely used and represents a temptingway to characterize developments in technological fields. The term appears in business as well as in academic domains. Consultancy firms offer technological hype cycle models to determine the state of development of technological fields

  2. Comparative energy analysis on a new regenerative Brayton cycle

    International Nuclear Information System (INIS)

    Goodarzi, M.

    2016-01-01

    Highlights: • New regenerative Brayton cycle has been introduced. • New cycle has higher thermal efficiency and lower exhausted heat per output power. • Regenerator may remain useful in the new cycle even at high pressure ratio. • New regenerative Brayton cycle is suggested for low pressure ratio operations. - Abstract: Gas turbines are frequently used for power generation. Brayton cycle is the basis for gas turbine operation and developing the alternative cycles. Regenerative Brayton cycle is a developed cycle for basic Brayton cycle with higher thermal efficiency at low to moderate pressure ratios. A new regenerative Brayton cycle has been introduced in the present study. Energy analysis has been conducted on ideal cycles to compare them from the first law of thermodynamics viewpoint. Comparative analyses showed that the new regenerative Brayton cycle has higher thermal efficiency than the original one at the same pressure ratio, and also lower heat absorption and exhausted heat per unite output power. Computed results show that new cycle improves thermal efficiency from 12% to 26% relative to the original regenerative Brayton cycle in the range of studied pressure ratios. Contrary to the original regenerative Brayton cycle, regenerator remains useful in the new regenerative Brayton cycle even at higher pressure ratio.

  3. COMPARATIVE PERFORMANCE OF COATED AND UNCOATED INSERTS DURING INTERMITTENT CUT MILLING OF AISI 4340 STEEL

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    SARAVANAN L.

    2015-05-01

    Full Text Available Machining behaviour of TiN coated and uncoated cemented carbide tools were studied during intermittent milling operation of AISI 4340 steel. Series of orthogonal intermittent milling tests were performed subsequently to investigate the role of the selected tools and cutting parameters. Three cutting parameters namely cutting speed, feed and depth of cut with three different levels and two types of cutting tools (coated and uncoated were considered for conducting the experimental trials. Intermittent face milling was employed to study the wear behaviour of the tools and the resulting surface roughness. The cyclic load induced during the entry and exit of the tool, leads to unstable temperature at cutting zone. This unstable temperature affects the tool life badly during intermittent milling. Tool wear increases considerably with an increase in frequency of the interruption. The experimental results indicated that the coated tool out performed uncoated tool in terms of tool life and surface finish. The other interesting observation was the uncoated tool performed better than coated tool at moderate cutting parameters. Results also indicated that the fracture and chipping were the dominant tool failure modes in uncoated tool. The chipping of uncoated tool causes the surface quality to deteriorate. TiN coating ensures the toughness of the cutting tool, which leads to good surface quality during the machining process. A detailed analysis of tool wear and surface roughness was done and the results are employed to create a linear regression model. This model established the relation between the cutting parameters and the response variables. ANOVA was used to identify the influential parameters which affect the tool wear and surface roughness.

  4. Comparing intermittency and network measurements of words and their dependence on authorship

    International Nuclear Information System (INIS)

    Amancio, Diego Raphael; Oliveira, Osvaldo N Jr; Fontoura Costa, Luciano da; Altmann, Eduardo G

    2011-01-01

    Many features of texts and languages can now be inferred from statistical analyses using concepts from complex networks and dynamical systems. In this paper, we quantify how topological properties of word co-occurrence networks and intermittency (or burstiness) in word distribution depend on the style of authors. Our database contains 40 books by eight authors who lived in the nineteenth and twentieth centuries, for which the following network measurements were obtained: the clustering coefficient, average shortest path lengths and betweenness. We found that the two factors with stronger dependence on authors were skewness in the distribution of word intermittency and the average shortest paths. Other factors such as betweenness and Zipf's law exponent show only weak dependence on authorship. Also assessed was the contribution from each measurement to authorship recognition using three machine learning methods. The best performance was about 65% accuracy upon combining complex networks and intermittency features with the nearest-neighbor algorithm of automatic authorship. From a detailed analysis of the interdependence of the various metrics, it is concluded that the methods used here are complementary for providing short- and long-scale perspectives on texts, which are useful for applications such as the identification of topical words and information retrieval. (paper)

  5. Comparative analysis of the flow activity of the Homoljska Potajnica intermittent spring

    Directory of Open Access Journals (Sweden)

    Igračev Nikola

    2014-01-01

    Full Text Available Homoljska Potajnica belongs to the type of a very rare, intermittent or rhythmic springs which appear exclusively in karst areas. It is one of the three known springs of this type in Serbia, while it is believed to be only about fifty of these in the rest of the world. As a rare karst and natural phenomenon, Homoljska Potajnica was a subject of interest for numerous researchers and geomorphologists in Serbia. Due to a very complex problem of occurence and the principle of functioning, to get the reliable data of how intemittent springs work, it is neccesarry to provide a continious observations, ussually in a long term period. This paper presents the results of the measurements of spring's flow activity and water discharge, taken in 2012. and 2013. These were carried out for comparison with the results of previous research, with an aim to determine possible changes in dynamics and mechanisms of spring's functioning in the past. One of the goals is to relate the annual precipitation regime with the intensity and frequency of spring activity, to try to determine the specific model of the spring's functioning. Another goal is to emphasize the need for continious observation in order to obtain the relevant data about the evolution of this rare natural phenomenon.

  6. Energy intermittency

    CERN Document Server

    Sorensen, Bent

    2014-01-01

    The first book to consider intermittency as a key point of an energy system, Energy Intermittency describes different levels of variability for traditional and renewable energy sources, presenting detailed solutions for handling energy intermittency through trade, collaboration, demand management, and active energy storage. Addressing energy supply intermittency systematically, this practical text:Analyzes typical time-distributions and intervals between episodes of demand-supply mismatch and explores their dependence on system layouts and energy source characteristicsSimulates scenarios regar

  7. Development of multilateral comparative evaluation method for fuel cycle system

    International Nuclear Information System (INIS)

    Tamaki, Hitoshi; Ikushima, Takeshi; Nomura, Yasushi; Nakajima, Kiyoshi.

    1998-03-01

    In the near future, Japanese nuclear fuel cycle system will be promoted by national nuclear energy policy, and it''s options i.e. once through, thermal cycle and fast breeder cycle must be selected by multilateral comparative evaluation method from various aspects of safety, society, economy, and e.t.c. Therefore such a problem can be recognized as a social problem of decision making and applied for AHP (Analytic Hierarchy Process) that can multilaterally and comparatively evaluate the problem. On comparative evaluation, much information are needed for decision making, therefore two kinds of databases having these information have been constructed. And then, the multilateral comparative evaluation method consisting of two kinds of databases and AHP for optimum selection of fuel cycle system option have been developed. (author)

  8. Comparative Life-Cycle Cost Analysis Of Solar Photovoltaic Power ...

    African Journals Online (AJOL)

    Comparative Life-Cycle Cost Analysis Of Solar Photovoltaic Power System And Diesel Generator System For Remote Residential Application In Nigeria. ... like capital cost, and diesel fuel costs are varied. The results show the photovoltaic system to be more cost-effective at low-power ranges of electrical energy supply.

  9. Comparative Study of Continuous Pralidoxime Infusion versus Intermittent Dosing: Application of High-Performance Liquid Chromatography Method on Serum of Organophosphate Poisoned Patients

    Directory of Open Access Journals (Sweden)

    Girish Thunga

    2013-09-01

    How to cite this article: Thunga G, Pandey S, Nair S, Mylapuri R, Vidyasagar S, Kunhikatta V, et al. Comparative Study of Continuous Pralidoxime Infusion versus Intermittent Dosing: Application of High-Performance Liquid Chromatography Method on Serum of Organophosphate Poisoned Patients. Asia Pac J Med Toxicol 2013;2:105-10.

  10. Intermittent character of interplanetary magnetic field fluctuations

    International Nuclear Information System (INIS)

    Bruno, Roberto; Carbone, Vincenzo; Chapman, Sandra; Hnat, Bogdan; Noullez, Alain; Sorriso-Valvo, Luca

    2007-01-01

    Interplanetary magnetic field magnitude fluctuations are notoriously more intermittent than velocity fluctuations in both fast and slow wind. This behavior has been interpreted in terms of the anomalous scaling observed in passive scalars in fully developed hydrodynamic turbulence. In this paper, the strong intermittent nature of the interplanetary magnetic field is briefly discussed comparing results performed during different phases of the solar cycle. The scaling properties of the interplanetary magnetic field magnitude show solar cycle variation that can be distinguished in the scaling exponents revealed by structure functions. The scaling exponents observed around the solar maximum coincide, within the errors, to those measured for passive scalars in hydrodynamic turbulence. However, it is also found that the values are not universal in the sense that the solar cycle variation may be reflected in dependence on the structure of the velocity field

  11. The effects of intermittent compared to continuous energy restriction on glycaemic control in type 2 diabetes; a pragmatic pilot trial.

    Science.gov (United States)

    Carter, S; Clifton, P M; Keogh, J B

    2016-12-01

    Weight loss improves glycaemic control in type 2 diabetes mellitus (T2DM). However, as achieving and maintaining weight loss is difficult, alternative strategies are needed. Our primary aim was to investigate the effects of intermittent energy restriction (IER) compared to continuous energy restriction (CER) on glycated haemoglobin A1c (HbA1c). Secondary aims were to assess effects on weight loss, body composition, medication changes and subjective measures of appetite. Using a 2-day IER method, we expected equal improvements to HbA1c and weight in both groups. Sixty-three overweight or obese participants (BMI 35.2±5kg/m 2 ) with T2DM (HbA1c 7.4±1.3%) (57mmol/mol) were randomised to a 2-day severe energy restriction (1670-2500kJ/day) with 5days of habitual eating, compared to a moderate CER diet (5000-6500kJ/day) for 12weeks. At 12weeks HbA1c (-0.7±0.9% P<0.001) and percent body weight reduction (-5.9±4% P<0.001) was similar in both groups with no group by time interaction. Similar reductions were also seen for medication dosages, all measures of body composition and subjective reports of appetite. In this pilot trial, 2days of IER compared with CER resulted in similar improvements in glycaemic control and weight reduction offering a suitable alternative treatment strategy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. A proof-of-concept study of short-cycle intermittent antiretroviral therapy with a once-daily regimen of didanosine, lamivudine, and efavirenz for the treatment of chronic HIV infection

    NARCIS (Netherlands)

    Dybul, M; Nies-Kraske, E; Dewar, R; Maldarelli, F; Hallahan, CW; Daucher, M; Piscitelli, SC; Ehler, L; Weigand, A; Palmer, S; Metcalf, JA; Davey, RT; Kress, DMR; Powers, A; Beck, [No Value; Frenkel, L; Baseler, M; Coffin, J; Fauci, AS

    2004-01-01

    Background. We previously demonstrated that short-cycle structured intermittent therapy ( SIT; 7 days without therapy followed by 7 days with antiretroviral therapy [ART]) with a ritonavir-boosted, indinavir-based, twice-daily regimen maintained suppression of plasma HIV viremia while reducing serum

  13. Comparative life cycle assessment of biodiesel and fossil diesel fuel

    International Nuclear Information System (INIS)

    Ceuterick, D.; Nocker, L. De; Spirinckx, C.

    1999-01-01

    Biofuels offer clear advantages in terms of greenhouse gas emissions, but do they perform better when we look at all the environmental impacts from a life cycle perspective. In the context of a demonstration project at the Flemish Institute for Technology Research (VITO) on the use of rapeseed methyl ester (RME) or biodiesel as automotive fuel, a life cycle assessment (LCA) of biodiesel and diesel was made. The primary concern was the question as to whether or not the biodiesel chain was comparable to the conventional diesel chain, from an environmental point of view, taking into account all stages of the life cycle of the two products. Additionally, environmental damage costs were calculated, using an impact pathway analysis. This paper presents the results of the two methods for evaluation of environmental impacts of RME and conventional diesel. Both methods are complementary and share the conclusion that although biodiesel has much lower greenhouse gas emissions, it still has significant impacts on other impact categories. The external costs of biodiesel are a bit lower compared to fossil diesel. For both fuels, external costs are significantly higher than the private production cost. (Author)

  14. Intermittent heating of buildings

    Energy Technology Data Exchange (ETDEWEB)

    Kohonen, K

    1983-02-01

    Conditions for intermittent heating of buildings are considered both theoretically and experimentally. Thermal behaviour of buildings adn rooms in intermittent heating is simulated by a program based on the convective heat balance equation and by simplified RC-models. The preheat times and the heating energy savings compared with continuous heating are presented for typical lightweight, mediumweight and heavyweight classroom and office modules. Formulaes for estimating the oversizing of the radiator network, the maximum heat output of heat exchangers in district heating and the efficiency of heating boilers in intermittent heating are presented. The preheat times and heating energy savings with different heating control systems are determined also experimentally in eight existing buildings. In addition some principles for the planning and application of intermittent heating systems are suggested.

  15. COMPARING CORONAL AND HELIOSPHERIC MAGNETIC FIELDS OVER SEVERAL SOLAR CYCLES

    Energy Technology Data Exchange (ETDEWEB)

    Koskela, J. S.; Virtanen, I. I.; Mursula, K., E-mail: jennimari.koskela@oulu.fi [University of Oulu, P.O. Box 3000, FI-90014 Oulu (Finland)

    2017-01-20

    Here we use the PFSS model and photospheric data from Wilcox Solar Observatory, SOHO /MDI, SDO/HMI, and SOLIS to compare the coronal field with heliospheric magnetic field measured at 1 au, compiled in the NASA/NSSDC OMNI 2 data set. We calculate their mutual polarity match and the power of the radial decay, p , of the radial field using different source surface distances and different number of harmonic multipoles. We find the average polarity match of 82% for the declining phase, 78%–79% for maxima, 76%–78% for the ascending phase, and 74%–76% for minima. On an average, the source surface of 3.25 R{sub S} gives the best polarity match. We also find strong evidence for solar cycle variation of the optimal source surface distance, with highest values (3.3 R{sub S}) during solar minima and lowest values (2.6 R{sub S}–2.7 R{sub S}) during the other three solar cycle phases. Raising the number of harmonic terms beyond 2 rarely improves the polarity match, showing that the structure of the HMF at 1 au is most of the time rather simple. All four data sets yield fairly similar polarity matches. Thus, polarity comparison is not affected by photospheric field scaling, unlike comparisons of the field intensity.

  16. Intermittent hydronephrosis

    International Nuclear Information System (INIS)

    Knop, J.; Vogel, H.; Hupe, W.

    1981-01-01

    An intermittent hydronephrosis was observed in a 40-year old patient. This disease pattern is due to an incongruity between the formation of urine and the transport capacity in the ureteropelvic junction. The latent impediment of flow becomes manifest with increased urine secretion. Irreversible renal damage can be the result of the repeatedly occurring hydronephrotic crises. (orig.) [de

  17. Comparing the Effect of Continuous and Intermittent Irrigation Techniques on Complications of Arterial Catheter and Partial Thromboplastin Time in Patients Following Coronary Artery Bypass Grafting Surgery

    Directory of Open Access Journals (Sweden)

    Sedigheh Arta

    2017-04-01

    Full Text Available Background: Different approaches are available to irrigate the arterial catheter, such as continuous and intermittent techniques. However, there is a disagreement regarding the most appropriate method. Aim: this study aimed to compare the effect of two continuous and intermittent irrigation methods on complications of arterial catheter and partial thromboplastin time (PTT in patients with coronary artery bypass (CABG surgery. Method: This randomized clinical trial was conducted on 60 participants undergoing coronary artery bypass grafting surgery in open-heart surgery ICU at Imam Reza hospital in Mashhad, Iran, in 2016. In continuous group, the arterial catheter was continuously irrigated with heparin solution at the rate of 2cc/h, and in the intermittent group with a syringe containing 5cc heparin solution every 3 hours. In both groups, catheter was monitored and recorded every 3 hours (until 48 hours and 3 times from enrollment in terms of complications of partial thromboplastin time. Data were analyzed using SPSS version 16. Results: The findingsof independent t-test showed that the two groups are homogeneous in age (P =0.48. The result of Fisher's exact test revealed no significant difference between the two groups in terms of average incidence of complications during the first 24 hours (P=0.55 and second 24 hours (P=0.55 after catheterization. Also during the 48 hours after surgery, independent t-test results showed no statistically significant difference in partial thromboplastin time (P=0.53 between the two groups. Implications for Practice: According to the results of the research based on the lack of difference between continuous and intermittent irrigation methods up to 48 hours after catheter replacement in terms of arterial catheter complications, further long-term follow-up researches are recommended.

  18. Comparative carbon cycle dynamics of the present and last interglacial

    Science.gov (United States)

    Brovkin, Victor; Brücher, Tim; Kleinen, Thomas; Zaehle, Sönke; Joos, Fortunat; Roth, Raphael; Spahni, Renato; Schmitt, Jochen; Fischer, Hubertus; Leuenberger, Markus; Stone, Emma J.; Ridgwell, Andy; Chappellaz, Jérôme; Kehrwald, Natalie; Barbante, Carlo; Blunier, Thomas; Dahl Jensen, Dorthe

    2016-04-01

    Changes in temperature and carbon dioxide during glacial cycles recorded in Antarctic ice cores are tightly coupled. However, this relationship does not hold for interglacials. While climate cooled towards the end of both the last (Eemian) and present (Holocene) interglacials, CO2 remained stable during the Eemian while rising in the Holocene. We identify and review twelve biogeochemical mechanisms of terrestrial (vegetation dynamics and CO2 fertilization, land use, wildfire, accumulation of peat, changes in permafrost carbon, subaerial volcanic outgassing) and marine origin (changes in sea surface temperature, carbonate compensation to deglaciation and terrestrial biosphere regrowth, shallow-water carbonate sedimentation, changes in the soft tissue pump, and methane hydrates), which potentially may have contributed to the CO2 dynamics during interglacials but which remain not well quantified. We use three Earth System Models (ESMs) of intermediate complexity to compare effects of selected mechanisms on the interglacial CO2 and δ13CO2 changes, focusing on those with substantial potential impacts: namely carbonate sedimentation in shallow waters, peat growth, and (in the case of the Holocene) human land use. A set of specified carbon cycle forcings could qualitatively explain atmospheric CO2 dynamics from 8 ka BP to the pre-industrial. However, when applied to Eemian boundary conditions from 126 to 115 ka BP, the same set of forcings led to disagreement with the observed direction of CO2 changes after 122 ka BP. This failure to simulate late-Eemian CO2 dynamics could be a result of the imposed forcings such as prescribed CaCO3 accumulation and/or an incorrect response of simulated terrestrial carbon to the surface cooling at the end of the interglacial. These experiments also reveal that key natural processes of interglacial CO2 dynamics - shallow water CaCO3 accumulation, peat and permafrost carbon dynamics - are not well represented in the current ESMs. Global

  19. Comparative environmental life cycle assessment of composite materials

    International Nuclear Information System (INIS)

    De Vegt, O.M.; Haije, W.G.

    1997-12-01

    The aim of the present study is to compare and quantify the environmental impact of three rotorblades made of different materials and to establish which stage in the life cycle contributes most. The life cycle of a product can be represented by the production phase, including depletion of raw materials (mining) and production (machining) of products, the utilisation phase, including use of energy, maintenance and cleaning, and the disposal phase, including landfill, incineration, recycling, etc. The environmental impact of a product is not only determined by the materials selected but also by the function of the product itself. E.g. when natural fibres are applied in vehicles as a substitution for metals the environmental impact in the use phase will be reduced due to a lower energy consumption caused by a lower car weight. The influence on the environmental impact of the production phase must also be taken into account. The material relation between the production phase and the use phase and the disposal phase is complicated. In general the lifetime of a product use phase can be extended (positive aspect), e.g. by application of a coating onto the surface. Due to the coating the product can not easily be recycled, which is a negative aspect. The three types of composites used in the rotorblade of the wind energy converter considered in this study are: flaxfibre reinforced epoxy, carbon fibre reinforced epoxy and glassfibre reinforced polyester. The assessment is performed using the computer program Simapro 3, which is based on the Dutch CML method for the environmental life-cycle assessment of products using the Eco-Indicator 95 evaluation method. The CML method defines five phases for an LCA: goal definition and scoping; inventory; classification; impact assessment; and improvement analysis. The improvement analysis is not part of this work. Performing an LCA is a time-consuming process due to the detailed information that is required. In chapter five some

  20. Comparative life cycle assessment of pistachio, almond and apple production

    Directory of Open Access Journals (Sweden)

    G. Bartzas

    2017-09-01

    Full Text Available A comparative life cycle assessment (LCA, with the use of GaBi 6 software and specific related databases, of three water intensive tree cultivation systems was conducted in order to evaluate environmental impacts and energy consumption. The tree crops are traditionally cultivated in two representative areas in Greece, namely Aegina island, Attica region, for pistachios and Agia, East Thessaly region, central Greece, for apples and almonds. The impact categories considered include global warming potential (GWP, eutrophication potential (EP, acidification potential (AP and cumulative energy demand (CED. Based upon the results obtained, it is deduced that pistachios and almonds show minor differences for all impact categories considered, while apples exhibit the best environmental profile. The phases of fertilizers production, irrigation system and field management were identified as the main “hot-spots” for all crops, exhibiting the highest environmental impacts and energy consumption. A sensitivity analysis was performed to explore actions that can be considered at farm scale, such as water desalination for irrigation purposes, transition to organic production and use of renewable energy, in order to reduce water requirements and promote energy conservation, especially in semi-arid and arid Mediterranean regions which suffer from water shortage and are prone to salinization. Finally, the results of this study were compared with the results derived from other relevant LCA studies.

  1. Midportion achilles tendon microcirculation after intermittent combined cryotherapy and compression compared with cryotherapy alone: a randomized trial.

    Science.gov (United States)

    Knobloch, Karsten; Grasemann, Ruth; Spies, Marcus; Vogt, Peter M

    2008-11-01

    The effect of combined cryotherapy/compression versus cryotherapy alone on the Achilles tendon is undetermined. Standardized combined cryotherapy/compression changes in midportion Achilles tendon microcirculation are superior to those with cryotherapy during intermittent application. Controlled laboratory study. Sixty volunteers were randomized for either combined cryotherapy/compression (Cryo/Cuff, DJO Inc, Vista, California: n = 30; 32 +/- 11 years) or cryotherapy alone (KoldBlue, TLP Industries, Kent, United Kingdom: n = 30; 33 +/- 12 years) with intermittent 3 x 10-minute application. Midportion Achilles tendon microcirculation was determined (O2C, LEA Medizintechnik, Giessen, Germany). Both Cryo/Cuff and KoldBlue significantly reduced superficial and deep capillary tendon blood flow within the first minute of application (43 +/- 46 arbitrary units [AU] vs 10 +/- 19 AU and 42 +/- 46 AU vs 12 +/- 10 AU; P = .0001) without a significant difference throughout all 3 applications. However, during recovery, superficial and deep capillary blood flow was reestablished significantly faster using Cryo/Cuff (P = .023). Tendon oxygen saturation was reduced in both groups significantly (3 minutes Cryo/Cuff: 36% +/- 20% vs 16% +/- 15%; KoldBlue: 42% +/- 19% vs 28% +/- 20%; P cryotherapy and compression with significantly increased tendon oxygen saturation during recovery in contrast to cryotherapy alone. Both regimens lead to a significant amelioration of tendinous venous outflow. Combined cryotherapy and compression is superior to cryotherapy alone regarding the Achilles tendon microcirculation. Further studies in tendinopathy and tendon rehabilitation are warranted to elucidate its value regarding functional issues.

  2. Intermittency '93

    International Nuclear Information System (INIS)

    Bialas, A.

    1993-01-01

    The existing data definitely indicate the existence of intermittency, i.e. of self similar structures in the systems of particles created in high-energy collisions. The effect seems universal: it was found in most of the processes investigated and its measures parameters depend only weakly (if at all) on the process in question. Strong HBT effect was found, suggesting that intermittency is related to space-time structure of the pion source rather than to detailed momentum structure of the production amplitudes. There are indications that this space time structure may be fractal, but more data is needed to establish this. The theoretical explanation remains obscure: it seems that both parton cascade and hadronization play an important role. Their interrelation, however, remains a mystery. 5 figs., 19 refs

  3. A comparative life cycle assessment of marine power systems

    International Nuclear Information System (INIS)

    Ling-Chin, Janie; Roskilly, Anthony P.

    2016-01-01

    Highlights: • Correlation among resources, emissions, key components and processes was attained. • Environmental benefits of innovative power systems were verified. • New-build system showed a great advantage over retrofit and conventional systems. • Relative contribution of significant components remained or became more profound. • Influence of fuel consumption quantity over the estimates varied with impact types. - Abstract: Despite growing interest in advanced marine power systems, knowledge gaps existed as it was uncertain which configuration would be more environmentally friendly. Using a conventional system as a reference, the comparative life cycle assessment (LCA) study aimed to compare and verify the environmental benefits of advanced marine power systems i.e. retrofit and new-build systems which incorporated emerging technologies. To estimate the environmental impact attributable to each system, a bottom-up integrated system approach was applied, i.e. LCA models were developed for individual components using GaBi, optimised operational profiles and input data standardised from various sources. The LCA models were assessed using CML2001, ILCD and Eco-Indicator99 methodologies. The estimates for the advanced systems were compared to those of the reference system. The inventory analysis results showed that both retrofit and new-build systems consumed less fuels (8.28% and 29.7% respectively) and released less emissions (5.2–16.6% and 29.7–55.5% respectively) during operation whilst more resources were consumed during manufacture, dismantling and the end of life. For 14 impact categories relevant to global warming, acidification, eutrophication, photochemical ozone creation and PM/respiratory inorganic health issues, reduction in LCIA results was achieved by retrofit (2.7–6.6%) and new-build systems (35.7–50.7%). The LCIA results of the retrofit system increased in ecotoxicity (1–8%), resource depletion (1–2%) and fossil fuel depletion

  4. Frozen-Thawed Embryo Transfer Cycles Have a Lower Incidence of Ectopic Pregnancy Compared With Fresh Embryo Transfer Cycles.

    Science.gov (United States)

    Zhang, Xinyu; Ma, Caihong; Wu, Zhangxin; Tao, Liyuan; Li, Rong; Liu, Ping; Qiao, Jie

    2017-01-01

    To evaluate the risk of ectopic pregnancy of embryo transfer. A retrospective cohort study on the incidence of ectopic pregnancy in fresh and frozen-thawed embryo transfer cycles from January 1 st , 2010, to January 1 st , 2015. Infertile women undergoing frozen-thawed transfer cycles or fresh transfer cycles. In-vitro fertilization, fresh embryo transfer, frozen-thawed embryo transfer, ectopic pregnancy. Ectopic pregnancy rate and clinical pregnancy rate. A total of 69 756 in vitro fertilization-embryo transfer cycles from 2010 to 2015 were analyzed, including 45 960 (65.9%) fresh and 23 796 (34.1%) frozen-thawed embryo transfer cycles. The clinical pregnancy rate per embryo transfer was slightly lower in fresh embryo transfer cycles compared with frozen-thawed embryo transfer cycles (40.8% vs 43.1%, P cycles, blastocyst transfer shows a significantly lower incidence of ectopic pregnancy (0.8% vs 1.8%, P = .002) in comparison with day 3 cleavage embryo transfer. The risk of ectopic pregnancy is lower in frozen-thawed embryo transfer cycles than fresh embryo transfer cycles, and blastocyst transfer could further decrease the ectopic pregnancy rate in frozen-thawed embryo transfer cycles.

  5. Does prolonged β-lactam infusions improve clinical outcomes compared to intermittent infusions? A meta-analysis and systematic review of randomized, controlled trials

    Directory of Open Access Journals (Sweden)

    Van Arendonk Kyle J

    2011-06-01

    Full Text Available Abstract Background The emergence of multi-drug resistant Gram-negatives (MDRGNs coupled with an alarming scarcity of new antibiotics has forced the optimization of the therapeutic potential of available antibiotics. To exploit the time above the minimum inhibitory concentration mechanism of β-lactams, prolonging their infusion may improve outcomes. The primary objective of this meta-analysis was to determine if prolonged β-lactam infusion resulted in decreased mortality and improved clinical cure compared to intermittent β-lactam infusion. Methods Relevant studies were identified from searches of MEDLINE, EMBASE, and CENTRAL. Heterogeneity was assessed qualitatively, in addition to I2 and Chi-square statistics. Pooled relative risks (RR and 95% confidence intervals (CI were calculated using Mantel-Haenszel random-effects models. Results Fourteen randomized controlled trials (RCTs were included. Prolonged infusion β-lactams were not associated with decreased mortality (n= 982; RR 0.92; 95% CI:0.61-1.37 or clinical cure (n = 1380; RR 1.00 95% CI:0.94-1.06 compared to intermittent infusions. Subgroup analysis for β-lactam subclasses and equivalent total daily β-lactam doses yielded similar results. Most studies had notable methodological flaws. Conclusions No clinical advantage was observed for prolonged infusion β-lactams. The limited number of studies with MDRGNs precluded evaluation of prolonged infusion of β-lactams for this subgroup. A large, multicenter RCT with critically ill patients infected with MDRGNs is needed.

  6. Intermittent hyperthyreosis

    International Nuclear Information System (INIS)

    Sulman, F.G.; Tal, E.; Pfeifer, Y.; Superstine, E.

    1975-01-01

    Intermittent hyperthyreosis occurs under various forms of stress, especially heat stress. The clinician may diagnose such cases as masked or apathetic hyperthyroidism or 'forme fruste' hyperthyreosis or thyroid autonomy. As most routine and standard tests may here yield inconsistent results, it is the patients' anamnesis which may provide the clue. Our Bioclimatology Unit has now seen over 100 cases in which thyroid hypersensitivity towards heat was the most prominent syndrome: 10-15% of weather-sensitive patients are affected. The patients complain before or during heat spells of such contradictory symptoms as insomnia, irritability, tension, tachycardia, palpitations, precordial pain, dyspnoe, flushes with sweating or chills, tremor, abdominal pain or diarrhea, polyuria or pollakisuria, weight loss in spite of ravenous appetite, fatigue, exhaustion, depression, adynamia, lack of concentration and confusion. Determination of urinary neurohormones allows a differential diagnosis, intermittent hyperthyreosis being characterized by three cardinal symptoms: tachycardia - every case with more than 80 pulse beats being suspect (not specific); urinary histamine - every case excreting more than 90 μg/day being suspect. Again the drawback of this test is its lack of specificity, as histamine may also be increased in cases of allergy and spondylitis; urinary thyroxine - every case excreting more than 20 μg/day T-4 being suspect. This is the only specific test. Therapy should make use of lithium carbonate and betablockers. Propyl thiouracil is rarely required. (orig.) [de

  7. Comparative techniques for nuclear fuel cycle waste management systems

    International Nuclear Information System (INIS)

    Pelto, P.J.; Voss, J.W.

    1979-09-01

    A safety assessment approach for the evaluation of predisposal waste management systems is described and applied to selected facilities in the light water reactor (LWR) once-through fuel cycle and a potential coprocessed UO 2 -PuO 2 fuel cycle. This approach includes a scoping analysis on pretreatment waste streams and a more detailed analysis on proposed waste management processes. The primary evaluation parameters used in this study include radiation exposures to the public from radionuclide releases from normal operations and potential accidents, occupational radiation exposure from normal operations, and capital and operating costs. On an overall basis, the waste management aspects of the two fuel cycles examined are quite similar. On an individual facility basis, the fuel coprocessing plant has the largest waste management impact

  8. Comparative analysis of thermodynamic performance and optimization of organic flash cycle (OFC) and organic Rankine cycle (ORC)

    International Nuclear Information System (INIS)

    Lee, Ho Yong; Park, Sang Hee; Kim, Kyoung Hoon

    2016-01-01

    A comparative thermodynamic performance and optimization analysis of basic organic flash cycle (OFCB), organic flash cycle with two-phase expander (OFCT), and organic Rankine cycle (ORC) activated by low-temperature sensible energy is carried out in the subcritical pressure regions. The three substances of R245fa, R123, and o-xylene are considered as the working fluids. Effects of cycle type, working fluid, and evaporation and source temperatures are systemically investigated on the system performance such as net power production, thermal and exergy efficiencies, and exergy destruction ratios at each component of the systems. Results show that the cycle type or working fluid which shows optimum performance depends on the source temperature, and organic flash cycle shows a potential for efficient recovery of low grade energy source.

  9. Comparative life cycle assessment of industrial multi-product processes

    OpenAIRE

    Jung, Johannes

    2014-01-01

    The demand for environmentally safe industrial processes is increasing. Therefore, environmental impacts of new processes have to be examined at an early stage. A method for analyzing environmental impacts is life cycle assessment (LCA). A major trouble of LCA are multi-functionality problems. Multi-functionality problems can be fixed using alternative methods such as system expansion, avoided burden and allocation. Each of the three methods requires choices by the LCA-practitioner. The choic...

  10. Comparative life cycle assessment and life cycle costing of lodging in the Himalaya

    NARCIS (Netherlands)

    Bhochhibhoya, Silu; Pizzol, Massimo; Achten, Wouter M.J.; Maskey, Ramesh Kumar; Zanetti, Michela; Cavalli, Raffaele

    2017-01-01

    Purpose: The main aim of the study is to assess the environmental and economic impacts of the lodging sector located in the Himalayan region of Nepal, from a life cycle perspective. The assessment should support decision making in technology and material selection for minimal environmental and

  11. The effect of running versus cycling high-intensity intermittent exercise on local tissue oxygenation and perceived enjoyment in 18–30-year-old sedentary men

    Science.gov (United States)

    Solomon, Colin

    2018-01-01

    Background High-intensity interval training (HIIT) has been proposed as a time-efficient exercise format to improve exercise adherence, thereby targeting the chronic disease burden associated with sedentary behaviour. Exercise mode (cycling, running), if self-selected, will likely affect the physiological and enjoyment responses to HIIT in sedentary individuals. Differences in physiological and enjoyment responses, associated with the mode of exercise, could potentially influence the uptake and continued adherence to HIIT. It was hypothesised that in young sedentary men, local and systemic oxygen utilisation and enjoyment would be higher during a session of running HIIT, compared to a session of cycling HIIT. Methods A total of 12 sedentary men (mean ± SD; age 24 ± 3 years) completed three exercise sessions: a maximal incremental exercise test on a treadmill (MAX) followed by two experiment conditions, (1) free-paced cycling HIIT on a bicycle ergometer (HIITCYC) and (2) constant-paced running HIIT on a treadmill ergometer (HIITRUN). Deoxygenated haemoglobin (HHb) in the gastrocnemius (GN), the left vastus lateralis (LVL) and the right vastus lateralis (RVL) muscles, oxygen consumption (VO2), heart rate (HR), ratings of perceived exertion (RPE) and physical activity enjoyment (PACES) were measured during HIITCYC and HIITRUN. Results There was a higher HHb in the LVL (p = 0.001) and RVL (p = 0.002) sites and a higher VO2 (p = 0.017) and HR (p HIIT produces higher levels of physiological stress when compared to constant-paced running HIIT. Participants perceived running HIIT to be more enjoyable than cycling HIIT. These findings have implications for selection of mode of HIIT for physical stress, exercise enjoyment and compliance.

  12. The effect of running versus cycling high-intensity intermittent exercise on local tissue oxygenation and perceived enjoyment in 18-30-year-old sedentary men.

    Science.gov (United States)

    Kriel, Yuri; Askew, Christopher D; Solomon, Colin

    2018-01-01

    High-intensity interval training (HIIT) has been proposed as a time-efficient exercise format to improve exercise adherence, thereby targeting the chronic disease burden associated with sedentary behaviour. Exercise mode (cycling, running), if self-selected, will likely affect the physiological and enjoyment responses to HIIT in sedentary individuals. Differences in physiological and enjoyment responses, associated with the mode of exercise, could potentially influence the uptake and continued adherence to HIIT. It was hypothesised that in young sedentary men, local and systemic oxygen utilisation and enjoyment would be higher during a session of running HIIT, compared to a session of cycling HIIT. A total of 12 sedentary men (mean ± SD; age 24 ± 3 years) completed three exercise sessions: a maximal incremental exercise test on a treadmill (MAX) followed by two experiment conditions, (1) free-paced cycling HIIT on a bicycle ergometer (HIITCYC) and (2) constant-paced running HIIT on a treadmill ergometer (HIITRUN). Deoxygenated haemoglobin (HHb) in the gastrocnemius (GN), the left vastus lateralis (LVL) and the right vastus lateralis (RVL) muscles, oxygen consumption (VO 2 ), heart rate (HR), ratings of perceived exertion (RPE) and physical activity enjoyment (PACES) were measured during HIITCYC and HIITRUN. There was a higher HHb in the LVL ( p = 0.001) and RVL ( p = 0.002) sites and a higher VO 2 ( p = 0.017) and HR ( p HIIT produces higher levels of physiological stress when compared to constant-paced running HIIT. Participants perceived running HIIT to be more enjoyable than cycling HIIT. These findings have implications for selection of mode of HIIT for physical stress, exercise enjoyment and compliance.

  13. Comparative life cycle assessment of standard and green roofs.

    Science.gov (United States)

    Saiz, Susana; Kennedy, Christopher; Bass, Brad; Pressnail, Kim

    2006-07-01

    Life cycle assessment (LCA) is used to evaluate the benefits, primarily from reduced energy consumption, resulting from the addition of a green roof to an eight story residential building in Madrid. Building energy use is simulated and a bottom-up LCA is conducted assuming a 50 year building life. The key property of a green roof is its low solar absorptance, which causes lower surface temperature, thereby reducing the heat flux through the roof. Savings in annual energy use are just over 1%, but summer cooling load is reduced by over 6% and reductions in peak hour cooling load in the upper floors reach 25%. By replacing the common flat roof with a green roof, environmental impacts are reduced by between 1.0 and 5.3%. Similar reductions might be achieved by using a white roof with additional insulation for winter, but more substantial reductions are achieved if common use of green roofs leads to reductions in the urban heat island.

  14. Comparing the effects of adaptive support ventilation and synchronized intermittent mandatory ventilation on intubation duration and hospital stay after coronary artery bypass graft surgery

    Directory of Open Access Journals (Sweden)

    Ahmadreza Yazdannik

    2016-01-01

    Full Text Available Background: Different modes of mechanical ventilation are used for respiratory support after coronary artery bypass graft (CABG. This study aimed to compare the effect(s of using adaptive support ventilation (ASV and synchronized intermittent mandatory ventilation (SIMV on the length of mechanical ventilation (intubation duration and hospital stay after coronary artery bypass graft surgery. Materials and Methods: In a randomized control trial, 64 patients were ventilated with ASV as the experiment group or with SIMV as the control group after CABG surgery in Chamran Hospital of Isfahan University of Medical Sciences. The time of tracheal intubation and the length of hospital stay were compared between the two groups. Data were analyzed and described using statistical analysis (independent t-test. Results: The mean time of intubation duration was significantly lower in ASV group compared with SIMV group. (4.83 h vs 6.71 h, P < 0.001. The lengths of hospital stay in the ASV and the SIMV groups were 140.6 h and 145.1 h, respectively. This difference was significant between the two groups (P = 0.006. Conclusions: According to the results of this study, using ASV mode for mechanical ventilation after CABG led to a decrease in intubation duration and also hospital stay in comparison with the SIMV group. It is recommended to use ASV mode on ventilators for respiratory support of patients undergoing coronary artery bypass graft surgery.

  15. Alzheimer’s Disease Mutant Mice Exhibit Reduced Brain Tissue Stiffness Compared to Wild-type Mice in both Normoxia and following Intermittent Hypoxia Mimicking Sleep Apnea

    Directory of Open Access Journals (Sweden)

    Maria José Menal

    2018-01-01

    Full Text Available BackgroundEvidence from patients and animal models suggests that obstructive sleep apnea (OSA may increase the risk of Alzheimer’s disease (AD and that AD is associated with reduced brain tissue stiffness.AimTo investigate whether intermittent hypoxia (IH alters brain cortex tissue stiffness in AD mutant mice exposed to IH mimicking OSA.MethodsSix-eight month old (B6C3-Tg(APPswe,PSEN1dE985Dbo/J AD mutant mice and wild-type (WT littermates were subjected to IH (21% O2 40 s to 5% O2 20 s; 6 h/day or normoxia for 8 weeks. After euthanasia, the stiffness (E of 200-μm brain cortex slices was measured by atomic force microscopy.ResultsTwo-way ANOVA indicated significant cortical softening and weight increase in AD mice compared to WT littermates, but no significant effects of IH on cortical stiffness and weight were detected. In addition, reduced myelin was apparent in AD (vs. WT, but no significant differences emerged in the cortex extracellular matrix components laminin and glycosaminoglycans when comparing baseline AD and WT mice.ConclusionAD mutant mice exhibit reduced brain tissue stiffness following both normoxia and IH mimicking sleep apnea, and such differences are commensurate with increased edema and demyelination in AD.

  16. A comparative analysis of rankine and absorption power cycles from exergoeconomic viewpoint

    International Nuclear Information System (INIS)

    Shokati, Naser; Ranjbar, Faramarz; Yari, Mortaza

    2014-01-01

    Highlights: • The Rankine and absorption power cycles are compared from exergoeconomic viewpoint. • The LiBr–H 2 O cycle has the highest unit cost of electricity produced by turbine. • The LiBr–H 2 O cycle has the lowest exergy destruction cost rate. • In LiBr–H 2 O cycle, the generator has the maximum value regarding (C-dot) D,k +(C-dot) L,k +(Z-dot) k . - Abstract: In this paper LiBr–H 2 O and NH 3 –H 2 O absorption power cycles and Rankine cycle which produce 1 MW electrical power in same conditions of heat sources are compared from exergoeconomic point of view. Exergoeconomic analysis is performed using the specific exergy costing (SPECO) method. The results show that among these cycles, although the LiBr–H 2 O cycle has the highest first law efficiency, but unit cost of electricity produced by turbine for LiBr–H 2 O cycle is more than that for Rankine cycle. This value is lowest for the NH 3 –H 2 O cycle. Moreover, the NH 3 –H 2 O cycle has the highest and the LiBr–H 2 O cycle has the lowest exergy destruction cost rate. The generator, the absorber and the boiler in all considered cycles have the maximum value of sum of cost rate associated with capital investment, operating and maintenance, exergy destruction and exergy losses. Therefore, these components should be taken into consideration from exergoeconomic viewpoint. In parametric study, it is observed that in the constant generator temperature, as the generator pressure increases, unit cost of power produced by turbine for LiBr–H 2 O and Rankine cycles decreases. This value for Rankine cycle is lower than for LiBr–H 2 O cycle whereas Rankine cycle efficiency is less than the efficiency of LiBr–H 2 O cycle. Also, in LiBr–H 2 O cycle, at constant temperature of the generator, the value of exergy destruction cost rate is minimized and exergoeconomic factor is maximized at particular values of generator pressure and the more absorber pressure results the minimum value of

  17. Safety Aspects of Radioactive Waste Management in Different Nuclear Fuel Cycle Policies, a Comparative Study

    International Nuclear Information System (INIS)

    Gad Allah, A.A.

    2009-01-01

    With the increasing demand of energy worldwide, and due to the depletion of conventional natural energy resources, energy policies in many countries have been devoted to nuclear energy option. On the other hand, adopting a safe and reliable nuclear fuel cycle concept guarantees future nuclear energy sustain ability is a vital request from environmental and economic point of views. The safety aspects of radioactive waste management in the nuclear fuel cycle is a topic of great importance relevant to public acceptance of nuclear energy and the development of nuclear technology. As a part of nuclear fuel cycle safety evaluation studies in the department of nuclear fuel cycle safety, National Center for Nuclear Safety and Radiation Control (NCNSRC), this study evaluates the radioactive waste management policies and radiological safety aspects of three different nuclear fuel cycle policies. The once-through fuel cycle (OT- fuel cycle) or the direct spent fuel disposal concept for both pressurized light water reactor ( PWR) and pressurized heavy water reactor (PHWR or CANDU) systems and the s elf-generated o r recycling fuel cycle concept in PWR have been considered in the assessment. The environmental radiological safety aspects of different nuclear fuel cycle options have been evaluated and discussed throughout the estimation of radioactive waste generated from spent fuel from these fuel cycle options. The decay heat stored in the spent fuel was estimated and a comparative safety study between the three fuel cycle policies has been implemented

  18. Prevention of deep vein thrombosis in potential neurosurgical patients. A randomized trial comparing graduated compression stockings alone or graduated compression stockings plus intermittent pneumatic compression with control

    International Nuclear Information System (INIS)

    Turpie, A.G.; Hirsh, J.; Gent, M.; Julian, D.; Johnson, J.

    1989-01-01

    In a randomized trial of neurosurgical patients, groups wearing graduated compression stockings alone (group 1) or graduated compression stockings plus intermittent pneumatic compression (IPC) (group 2) were compared with an untreated control group in the prevention of deep vein thrombosis (DVT). In both active treatment groups, the graduated compression stockings were continued for 14 days or until hospital discharge, if earlier. In group 2, IPC was continued for seven days. All patients underwent DVT surveillance with iodine 125-labeled fibrinogen leg scanning and impedance plethysmography. Venography was carried out if either test became abnormal. Deep vein thrombosis occurred in seven (8.8%) of 80 patients in group 1, in seven (9.0%) of 78 patients in group 2, and in 16 (19.8%) of 81 patients in the control group. The observed differences among these rates are statistically significant. The results of this study indicate that graduated compression stockings alone or in combination with IPC are effective methods of preventing DVT in neurosurgical patients

  19. Comparative analysis of methods and tools for open and closed fuel cycles modeling: MESSAGE and DESAE

    International Nuclear Information System (INIS)

    Andrianov, A.A.; Korovin, Yu.A.; Murogov, V.M.; Fedorova, E.V.; Fesenko, G.A.

    2006-01-01

    Comparative analysis of optimization and simulation methods by the example of MESSAGE and DESAE programs is carried out for nuclear power prospects and advanced fuel cycles modeling. Test calculations for open and two-component nuclear power and closed fuel cycle are performed. Auxiliary simulation-dynamic model is developed to specify MESSAGE and DESAE modeling approaches difference. The model description is given [ru

  20. Life cycle assessment of a commercial rainwater harvesting system compared with a municipal water supply system

    Science.gov (United States)

    Building upon previously published life cycle assessment (LCA) methodologies, we conducted an LCA of a commercial rainwater harvesting (RWH) system and compared it to a municipal water supply (MWS) system adapted to Washington, D.C. Eleven life cycle impact assessment (LCIA) indi...

  1. Parametric optimization and comparative study of organic Rankine cycle (ORC) for low grade waste heat recovery

    International Nuclear Information System (INIS)

    Dai Yiping; Wang Jiangfeng; Gao Lin

    2009-01-01

    Organic Rankine cycles for low grade waste heat recovery are described with different working fluids. The effects of the thermodynamic parameters on the ORC performance are examined, and the thermodynamic parameters of the ORC for each working fluid are optimized with exergy efficiency as an objective function by means of the genetic algorithm. The optimum performance of cycles with different working fluids was compared and analyzed under the same waste heat condition. The results show that the cycles with organic working fluids are much better than the cycle with water in converting low grade waste heat to useful work. The cycle with R236EA has the highest exergy efficiency, and adding an internal heat exchanger into the ORC system could not improve the performance under the given waste heat condition. In addition, for the working fluids with non-positive saturation vapor curve slope, the cycle has the best performance property with saturated vapor at the turbine inlet

  2. Intermittent behavior of the logistic system

    Science.gov (United States)

    Mayer-Kress, G.; Haken, H.

    1981-03-01

    In the discrete logistic model a transition to chaotic behavior via intermittency occurs in a neighborhood of periodic bands. Intermittent behavior is also induced if a stable periodic orbit is perturbed by low-level external noise, whereas alterations due to computer digitalisation produce remarkable periodicities. We compare our numerical results with the predictions of Pomeau and Manneville for the Lorenz system.

  3. Intermittency in 197Au fragmentation

    International Nuclear Information System (INIS)

    Dabrowska, A.; Holynski, R.; Olszewski, A.; Szarska, M.; Wilczynska, B.; Wolter, W.; Wosiek, B.; Cherry, M.L.; Deines-Jones, P.; Jones, W.V.; Sengupta, K.; Wefel, B.

    1995-07-01

    The concept of factorial moments was applied to an analysis of the dynamical fluctuations in the charge distributions of the fragments emitted from gold nuclei with energies 10.6 and < 1.0 GeV/n interacting with emulsion nuclei. Clear evidence for intermittent fluctuations has been found in an analysis using all the particles released from the gold projectile, with a stronger effect observed below 1 GeV/n than at 10.6 GeV/n. For the full data sets, however, the intermittency effect was found to be very sensitive to the singly charged particles, and neglecting these particles strongly reduces the intermittency signal. When the analysis is restricted to the multiply charged fragments, an intermittency effect is revealed only for multifragmentation events, although one that is enhanced as compared to the analysis of all, singly and multiply charged, particles. The properties of the anomalous fractal dimensions suggest a sequential decay mechanism, rather than the existence of possible critical behaviour in the process of nuclear fragmentation. The likely influence of the charge conservation effects and the finite size of decaying systems on the observed intermittency signals was pointed out. (author). 37 refs, 9 figs, 5 tabs

  4. Exergoeconomic analysis of utilizing the transcritical CO_2 cycle and the ORC for a recompression supercritical CO_2 cycle waste heat recovery: A comparative study

    International Nuclear Information System (INIS)

    Wang, Xurong; Dai, Yiping

    2016-01-01

    Highlights: • An exergoeconomic analysis is performed for sCO_2/tCO_2 cycle. • Performance of the sCO_2/tCO_2 cycle and sCO_2/ORC cycle are presented and compared. • The sCO_2/tCO_2 cycle performs better than the sCO_2/ORC cycle at lower PRc. • The sCO_2/tCO_2 cycle has comparable total product unit cost with the sCO_2/ORC cycle. - Abstract: Two combined cogeneration cycles are examined in which the waste heat from a recompression supercritical CO_2 Brayton cycle (sCO_2) is recovered by either a transcritical CO_2 cycle (tCO_2) or an Organic Rankine Cycle (ORC) for generating electricity. An exergoeconomic analysis is performed for sCO_2/tCO_2 cycle performance and its comparison to the sCO_2/ORC cycle. The following organic fluids are considered as the working fluids in the ORC: R123, R245fa, toluene, isobutane, isopentane and cyclohexane. Thermodynamic and exergoeconomic models are developed for the cycles on the basis of mass and energy conservations, exergy balance and exergy cost equations. Parametric investigations are conducted to evaluate the influence of decision variables on the performance of sCO_2/tCO_2 and sCO_2/ORC cycles. The performance of these cycles is optimized and then compared. The results show that the sCO_2/tCO_2 cycle is preferable and performs better than the sCO_2/ORC cycle at lower PRc. When the sCO_2 cycle operates at a cycle maximum pressure of around 20 MPa (∼2.8 of PRc), the tCO_2 cycle is preferable to be integrated with the recompression sCO_2 cycle considering the off-design conditions. Moreover, contrary to the sCO_2/ORC system, a higher tCO_2 turbine inlet temperature improves exergoeconomic performance of the sCO_2/tCO_2 cycle. The thermodynamic optimization study reveals that the sCO_2/tCO_2 cycle has comparable second law efficiency with the sCO_2/ORC cycle. When the optimization is conducted based on the exergoeconomics, the total product unit cost of the sCO_2/ORC is slightly lower than that of the sCO_2/tCO_2

  5. A randomized study comparing IVF in the unstimulated cycle with IVF-following clomiphene citrate

    DEFF Research Database (Denmark)

    Ingerslev, Hans Jakob; Højgaard, A.; Hindkjær, Johnny Juhl

    2001-01-01

    The efficiency of IVF in unstimulated cycles was compared with that following ovarian stimulation with clomiphene citrate in a simple protocol with ultrasound monitoring only. A total of 132 couples with no previous IVF attempts, selected by female age ... protocol, but not IVF in unstimulated cycles, seems compatible with the concept of `friendly IVF', yielding a fair pregnancy rate both per cycle started and per embryo transfer in selected patients. The results do not substantiate any important negative anti-oestrogenic effects of clomiphene....

  6. Quantified Uncertainties in Comparative Life Cycle Assessment : What Can Be Concluded?

    NARCIS (Netherlands)

    Mendoza Beltran, Angelica; Prado, Valentina; Font Vivanco, David; Henriksson, Patrik J.G.; Guinée, Jeroen B.; Heijungs, Reinout

    2018-01-01

    Interpretation of comparative Life Cycle Assessment (LCA) results can be challenging in the presence of uncertainty. To aid in interpreting such results under the goal of any comparative LCA, we aim to provide guidance to practitioners by gaining insights into uncertainty-statistics methods (USMs).

  7. Intermittent search strategies

    Science.gov (United States)

    Bénichou, O.; Loverdo, C.; Moreau, M.; Voituriez, R.

    2011-01-01

    This review examines intermittent target search strategies, which combine phases of slow motion, allowing the searcher to detect the target, and phases of fast motion during which targets cannot be detected. It is first shown that intermittent search strategies are actually widely observed at various scales. At the macroscopic scale, this is, for example, the case of animals looking for food; at the microscopic scale, intermittent transport patterns are involved in a reaction pathway of DNA-binding proteins as well as in intracellular transport. Second, generic stochastic models are introduced, which show that intermittent strategies are efficient strategies that enable the minimization of search time. This suggests that the intrinsic efficiency of intermittent search strategies could justify their frequent observation in nature. Last, beyond these modeling aspects, it is proposed that intermittent strategies could also be used in a broader context to design and accelerate search processes.

  8. Comparative assessment of nuclear fuel cycles. Light-water reactor once-through, classical fast breeder reactor, and symbiotic fast breeder reactor cycles

    International Nuclear Information System (INIS)

    Hardie, R.W.; Barrett, R.J.; Freiwald, J.G.

    1980-06-01

    The object of the Alternative Nuclear Fuel Cycle Study is to perform comparative assessments of nuclear power systems. There are two important features of this study. First, this evaluation attempts to encompass the complete, integrated fuel cycle from mining of uranium ore to disposal of waste rather than isolated components. Second, it compares several aspects of each cycle - energy use, economics, technological status, proliferation, public safety, and commercial potential - instead of concentrating on one or two assessment areas. This report presents assessment results for three fuel cycles. These are the light-water reactor once-through cycle, the fast breeder reactor on the classical plutonium cycle, and the fast breeder reactor on a symbiotic cycle using plutonium and 233 U as fissile fuels. The report also contains a description of the methodology used in this assessment. Subsequent reports will present results for additional fuel cycles

  9. Cosmic Rays in Intermittent Magnetic Fields

    International Nuclear Information System (INIS)

    Shukurov, Anvar; Seta, Amit; Bushby, Paul J.; Wood, Toby S.; Snodin, Andrew P.

    2017-01-01

    The propagation of cosmic rays in turbulent magnetic fields is a diffusive process driven by the scattering of the charged particles by random magnetic fluctuations. Such fields are usually highly intermittent, consisting of intense magnetic filaments and ribbons surrounded by weaker, unstructured fluctuations. Studies of cosmic-ray propagation have largely overlooked intermittency, instead adopting Gaussian random magnetic fields. Using test particle simulations, we calculate cosmic-ray diffusivity in intermittent, dynamo-generated magnetic fields. The results are compared with those obtained from non-intermittent magnetic fields having identical power spectra. The presence of magnetic intermittency significantly enhances cosmic-ray diffusion over a wide range of particle energies. We demonstrate that the results can be interpreted in terms of a correlated random walk.

  10. Cosmic Rays in Intermittent Magnetic Fields

    Energy Technology Data Exchange (ETDEWEB)

    Shukurov, Anvar; Seta, Amit; Bushby, Paul J.; Wood, Toby S. [School of Mathematics and Statistics, Newcastle University, Newcastle Upon Tyne NE1 7RU (United Kingdom); Snodin, Andrew P., E-mail: a.seta1@ncl.ac.uk, E-mail: amitseta90@gmail.com [Department of Mathematics, Faculty of Applied Science, King Mongkut’s University of Technology North Bangkok, Bangkok 10800 (Thailand)

    2017-04-10

    The propagation of cosmic rays in turbulent magnetic fields is a diffusive process driven by the scattering of the charged particles by random magnetic fluctuations. Such fields are usually highly intermittent, consisting of intense magnetic filaments and ribbons surrounded by weaker, unstructured fluctuations. Studies of cosmic-ray propagation have largely overlooked intermittency, instead adopting Gaussian random magnetic fields. Using test particle simulations, we calculate cosmic-ray diffusivity in intermittent, dynamo-generated magnetic fields. The results are compared with those obtained from non-intermittent magnetic fields having identical power spectra. The presence of magnetic intermittency significantly enhances cosmic-ray diffusion over a wide range of particle energies. We demonstrate that the results can be interpreted in terms of a correlated random walk.

  11. Cell cycle accumulation of the proliferating cell nuclear antigen PCN-1 transitions from continuous in the adult germline to intermittent in the early embryo of C. elegans.

    Science.gov (United States)

    Kocsisova, Zuzana; Kornfeld, Kerry; Schedl, Tim

    2018-05-30

    The proliferating cell nuclear antigen (PCNA or PCN-1 in C. elegans), an essential processivity factor for DNA polymerase δ, has been widely used as a marker of S-phase. In C. elegans early embryos, PCN-1 accumulation is cyclic, localizing to the nucleus during S-phase and the cytoplasm during the rest of the cell cycle. The C. elegans larval and adult germline is an important model systems for studying cell cycle regulation, and it was observed that the cell cycle regulator cyclin E (CYE-1 in C. elegans) displays a non-cyclic, continuous accumulation pattern in this tissue. The accumulation pattern of PCN-1 has not been well defined in the larval and adult germline, and the objective of this study was to determine if the accumulation pattern is cyclic, as in other cells and organisms, or continuous, similar to cyclin E. To study the larval and adult germline accumulation of PCN-1 expressed from its native locus, we used CRISPR/Cas9 technology to engineer a novel allele of pcn-1 that encodes an epitope-tagged protein. S-phase nuclei were labeled using EdU nucleotide incorporation, and FLAG::PCN-1 was detected by antibody staining. All progenitor zone nuclei, including those that were not in S-phase (as they were negative for EdU staining) showed PCN-1 accumulation, indicating that PCN-1 accumulated during all cell cycle phases in the germline progenitor zone. The same result was observed with a GFP::PCN-1 fusion protein expressed from a transgene. pcn-1 loss-of-function mutations were analyzed, and pcn-1 was necessary for robust fertility and embryonic development. In the C. elegans early embryo as well as other organisms, PCN-1 accumulates in nuclei only during S-phase. By contrast, in the progenitor zone of the germline of C. elegans, PCN-1 accumulated in nuclei during all cell cycle stages. This pattern is similar to accumulation pattern of cyclin E. These observations support the model that mitotic cell cycle regulation in the germline stem and progenitor

  12. A novel method for rapid comparative quantitative analysis of nuclear fuel cycles

    International Nuclear Information System (INIS)

    Eastham, Sebastian D.; Coates, David J.; Parks, Geoffrey T.

    2012-01-01

    Highlights: ► Metric framework determined to compare nuclear fuel cycles. ► Fast and thermal reactors simulated using MATLAB models, including thorium. ► Modelling uses deterministic methods instead of Monte–Carlo for speed. ► Method rapidly identifies relative cycle strengths and weaknesses. ► Significant scope for use in project planning and cycle optimisation. - Abstract: One of the greatest obstacles facing the nuclear industry is that of sustainability, both in terms of the finite reserves of uranium ore and the production of highly radiotoxic spent fuel which presents proliferation and environmental hazards. Alternative nuclear technologies have been suggested as a means of delivering enhanced sustainability with proposals including fast reactors, the use of thorium fuel and tiered fuel cycles. The debate as to which is the most appropriate technology continues, with each fuel system and reactor type delivering specific advantages and disadvantages which can be difficult to compare fairly. This paper demonstrates a framework of performance metrics which, coupled with a first-order lumped reactor model to determine nuclide population balances, can be used to quantify the aforementioned pros and cons for a range of different fuel and reactor combinations. The framework includes metrics such as fuel efficiency, spent fuel toxicity and proliferation resistance, and relative cycle performance is analysed through parallel coordinate plots, yielding a quantitative comparison of disparate cycles.

  13. Comparative performance analysis of combined-cycle pulse detonation turbofan engines (PDTEs

    Directory of Open Access Journals (Sweden)

    Sudip Bhattrai

    2013-09-01

    Full Text Available Combined-cycle pulse detonation engines are promising contenders for hypersonic propulsion systems. In the present study, design and propulsive performance analysis of combined-cycle pulse detonation turbofan engines (PDTEs is presented. Analysis is done with respect to Mach number at two consecutive modes of operation: (1 Combined-cycle PDTE using a pulse detonation afterburner mode (PDA-mode and (2 combined-cycle PDTE in pulse detonation ramjet engine mode (PDRE-mode. The performance of combined-cycle PDTEs is compared with baseline afterburning turbofan and ramjet engines. The comparison of afterburning modes is done for Mach numbers from 0 to 3 at 15.24 km altitude conditions, while that of pulse detonation ramjet engine (PDRE is done for Mach 1.5 to Mach 6 at 18.3 km altitude conditions. The analysis shows that the propulsive performance of a turbine engine can be greatly improved by replacing the conventional afterburner with a pulse detonation afterburner (PDA. The PDRE also outperforms its ramjet counterpart at all flight conditions considered herein. The gains obtained are outstanding for both the combined-cycle PDTE modes compared to baseline turbofan and ramjet engines.

  14. Distraction, not hunger, is associated with lower mood and lower perceived work performance on fast compared to non-fast days during intermittent fasting.

    Science.gov (United States)

    Appleton, Katherine M; Baker, Stephanie

    2015-06-01

    Using a repeated measures design, 16 females recorded hunger, distraction, mood and perceived work performance on two consecutive fast days, on two earlier and on two subsequent consecutive non-fast days, during intermittent fasting. Using regression analyses, low positive mood was associated with higher distraction (β = -0.38, p < 0.01), and lower perceived work performance was associated with higher distraction (β = -0.50, p < 0.01) and lower positive mood (β = 0.59, p = 0.01). No associations were found with hunger (largest β = -0.11, p = 0.15). Associations between mood, perceived work performance and distraction but not hunger mirror those found in traditional dieting and suggest no benefit for attention from intermittent fasting-type regimes. © The Author(s) 2015.

  15. The radiological risks associated with the thorium fuelled HTGR fuel cycle. A comparative risk evaluation

    International Nuclear Information System (INIS)

    Dodd, D.H.; Hienen, J.F.A. van.

    1995-10-01

    This report presents the results of task B.3 of the 'Technology Assessment of the High Temperature Reactor' project. The objective of task B.3 was to evaluate the radiological risks to the general public associated with the sustainable HTGR cycle. Since the technologies to be used at several stages of this fuel cycle are still in the design phase and since a detailed specification of this fuel cycle has not yet been developed, the emphasis was on obtaining a global impression of the risk associated with a generic thorium-based HTGR fuel cycle. This impression was obtained by performing a comparative risk analysis on the basis of data given in the literature. As reference for the comparison a generic uranium fuelled LWR cycle was used. The major benefit with respect to the radiological rsiks of basing the fuel cycle around modular HTGR technology instead of the LWR technology is the increase in reactor safety. The design of the modular HTGR is expected to prevent the release of a significant amount of radioactive material to the environment, and hence early deaths in the surrounding population, during accident conditions. This implies that there is no group risk as defined in the Dutch risk management policy. The major benefit of thorium based fuel cycles over uranium based fuel cycles is the reduction in the radiological risks from unraium mining and milling. The other stages of the nuclear fuel cycle which make a significant contribution to the radiological risks are electricity generation, reprocessing and final disposal. The risks associated with the electricity generation stage are dominated by the risks from fission products, activated corrosion products and the activation products tritium and carbon-14. The risks associated with the reprocessing stage are determined by fission and activation products (including actinides). (orig./WL)

  16. The radiological risks associated with the thorium fuelled HTGR fuel cycle. A comparative risk evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Dodd, D.H.; Hienen, J.F.A. van

    1995-10-01

    This report presents the results of task B.3 of the `Technology Assessment of the High Temperature Reactor` project. The objective of task B.3 was to evaluate the radiological risks to the general public associated with the sustainable HTGR cycle. Since the technologies to be used at several stages of this fuel cycle are still in the design phase and since a detailed specification of this fuel cycle has not yet been developed, the emphasis was on obtaining a global impression of the risk associated with a generic thorium-based HTGR fuel cycle. This impression was obtained by performing a comparative risk analysis on the basis of data given in the literature. As reference for the comparison a generic uranium fuelled LWR cycle was used. The major benefit with respect to the radiological rsiks of basing the fuel cycle around modular HTGR technology instead of the LWR technology is the increase in reactor safety. The design of the modular HTGR is expected to prevent the release of a significant amount of radioactive material to the environment, and hence early deaths in the surrounding population, during accident conditions. This implies that there is no group risk as defined in the Dutch risk management policy. The major benefit of thorium based fuel cycles over uranium based fuel cycles is the reduction in the radiological risks from unraium mining and milling. The other stages of the nuclear fuel cycle which make a significant contribution to the radiological risks are electricity generation, reprocessing and final disposal. The risks associated with the electricity generation stage are dominated by the risks from fission products, activated corrosion products and the activation products tritium and carbon-14. The risks associated with the reprocessing stage are determined by fission and activation products (including actinides). (orig./WL).

  17. Forces and energetics of intermittent swimming

    Science.gov (United States)

    Floryan, Daniel; Van Buren, Tyler; Smits, Alexander J.

    2017-08-01

    Experiments are reported on intermittent swimming motions. Water tunnel experiments on a nominally two-dimensional pitching foil show that the mean thrust and power scale linearly with the duty cycle, from a value of 0.2 all the way up to continuous motions, indicating that individual bursts of activity in intermittent motions are independent of each other. This conclusion is corroborated by particle image velocimetry (PIV) flow visualizations, which show that the main vortical structures in the wake do not change with duty cycle. The experimental data also demonstrate that intermittent motions are generally energetically advantageous over continuous motions. When metabolic energy losses are taken into account, this conclusion is maintained for metabolic power fractions less than 1.

  18. Intermittency in branching models

    International Nuclear Information System (INIS)

    Chiu, C.B.; Texas Univ., Austin; Hwa, R.C.; Oregon Univ., Eugene

    1990-01-01

    The intermittency properties of three branching models have been investigated. The factorial moments show power-law behavior as function of small rapidity width. The slopes and energy dependences reveal different characteristics of the models. The gluon model has the weakest intermittency. (orig.)

  19. A seven day running training period increases basal urinary hepcidin levels as compared to cycling

    NARCIS (Netherlands)

    Sim, M.; Dawson, B.; Landers, G.J.; Swinkels, D.W.; Tjalsma, H.; Wiegerinck, E.T.G.; Trinder, D.; Peeling, P.

    2014-01-01

    BACKGROUND: This investigation compared the effects of an extended period of weight-bearing (running) vs. non-weight-bearing (cycling) exercise on hepcidin production and its implications for iron status. METHODS: Ten active males performed two separate exercise training blocks with either running

  20. Comparative evaluation of life cycle assessment models for solid waste management

    International Nuclear Information System (INIS)

    Winkler, Joerg; Bilitewski, Bernd

    2007-01-01

    This publication compares a selection of six different models developed in Europe and America by research organisations, industry associations and governmental institutions. The comparison of the models reveals the variations in the results and the differences in the conclusions of an LCA study done with these models. The models are compared by modelling a specific case - the waste management system of Dresden, Germany - with each model and an in-detail comparison of the life cycle inventory results. Moreover, a life cycle impact assessment shows if the LCA results of each model allows for comparable and consecutive conclusions, which do not contradict the conclusions derived from the other models' results. Furthermore, the influence of different level of detail in the life cycle inventory of the life cycle assessment is demonstrated. The model comparison revealed that the variations in the LCA results calculated by the models for the case show high variations and are not negligible. In some cases the high variations in results lead to contradictory conclusions concerning the environmental performance of the waste management processes. The static, linear modelling approach chosen by all models analysed is inappropriate for reflecting actual conditions. Moreover, it was found that although the models' approach to LCA is comparable on a general level, the level of detail implemented in the software tools is very different

  1. Effect of ovariectomy on inflammation induced by intermittent hypoxia in a mouse model of sleep apnea.

    Science.gov (United States)

    Torres, Marta; Palomer, Xavier; Montserrat, Josep M; Vázquez-Carrera, Manel; Farré, Ramon

    2014-10-01

    Patient data report marked gender and pre-vs-postmenopausal differences in obstructive sleep apnea (OSA). However, no experimental data are available on how sexual hormones modulate OSA consequences. Here we report novel results on estrogen-modulated heart and brain inflammation in female mice subjected to intermittent hypoxia, a major injurious challenge in OSA. C57BL/6J (14-week old) intact and ovariectomized mice (n=6 each) were subjected to intermittent hypoxia (20 s at 5% and 40s at 21%, 60 cycles/h; 6 h/day). Identical intact and ovariectomized groups breathing room air were controls. After 30 days, the gene expressions of interleukins 6 and 8 (IL-6, IL-8) in the brain and heart tissues were measured. Whereas, compared with normoxia, intermittent hypoxia considerably increased IL-6 and IL-8 gene expressions in intact females, no change was found in ovariectomized mice when comparing normoxia and intermittent hypoxia. These data suggest that estrogens modulate the inflammatory effects of intermittent hypoxia and point to further studies on the role played by sex hormones in OSA. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Comparative analysis of the life cycle impact assessment of available cement inventories in the EU

    International Nuclear Information System (INIS)

    Josa, Alejandro; Aguado, Antonio; Cardim, Arnaldo; Byars, Ewan

    2007-01-01

    Life cycle impact assessment (LCIA) is one of basic steps in life cycle assessment methodology (LCA). This paper presents a comparative study of the LCIA of different life cycle inventories (LCI) for EU cements. The analysis unit used is the manufacture of 1 kg of cement, from 'cradle to gate'. The impact categories considered are those resulting from the manufacture of cement and include greenhouse effects, acidification, eutrophication and summer and winter smog, amongst others. The results of the study highlighted some inconsistencies in existing inventories. As for the LCIA, the main environmental interventions related to cement manufacture were classified and characterised and their effect on different impact categories analysed. Differences observed in evaluation of the impact of cement type were essentially related to their clinker content

  3. Alcohol Intake Increases in Adolescent C57BL/6J Mice during Intermittent Cycles of Phase-Delayed, Long-Light Conditions

    Directory of Open Access Journals (Sweden)

    Joshua J. Gamsby

    2017-08-01

    Full Text Available Adolescents naturally go to bed and awaken late, but are forced to awaken early for school and work. This leads to “social jetlag”, a state of circadian desynchrony (CD, in which internal biological rhythms are out of sync with behavioral rhythms. CD is associated with increased alcohol intake in adults, but has been less well-studied in adolescents. The goal of this study was to model adolescent alcohol intake during similar CD conditions in male C57BL/6J mice. Free access alcohol intake, water intake and wheel-running activity were measured during a normal 12HR photoperiod or during alternating photoperiod (Experiment 1: 12 h light for 4 days followed by 18 h light for 3 days, with dark (activity onset delayed 9 h during the 18HR photoperiod; Experiment 2: 12 h light for 4 days followed by 6 h light for 3 days, with dark onset delayed 3 h during the 6HR photoperiod. In Experiment 1, CD produced a small but significant increase in the total alcohol intake per day as well as in intake in bouts, with the greatest increase over controls in the hours following the 6HR dark period. Additionally, the pattern of alcohol intake in bouts shifted to increase alcohol intake during the shorter dark period. In Experiment 2, the opposite effect occurred—the longer dark cycle led to lower alcohol drinking in the second half of the dark period. However, in Experiment 2, CD produced no significant changes in either total alcohol intake or alcohol intake in bouts. Conclusion: shifts in the light cycle that disrupt the regular pattern of day and night, and increase the length of the night phase, are sufficient to increase both drinking in bouts and restricted drinking in adolescent mice, modeling increased alcohol intake in adolescents during CD.

  4. A comparative study of the safety and economics of fusion fuel cycles

    International Nuclear Information System (INIS)

    Brereton, S.J.; Kazimi, M.S.

    1988-01-01

    The safety and economic characteristics of the deuterium-tritium (DT), deuterium-deuterium (DD) and deuterium-helium-3 (DHe) fusion fuel cycles have been compared. Representative tokamak designs for each fuel cycle were established based on consistent design criteria, using modest extrapolations of present day technologies. The economic analysis of these designs took into account the possible variation in capital and operating costs, and plant availability. Safety analyses examined tritium inventories, routine tritium releases, inventories of activation products and the level of hazard associated with plant wastes. The annual dose incurred by plant workers was estimated for all fuel cycles. The impact of using a reduced activation steel as a blanket material on the economics and safety during normal conditions for the DD fuel cycle was examined. A loss of coolant accident (LOCA) was investigated to determine the relative safety and economic impact of this event for the various fuel cycles. Finally, a cost/benefit analysis was performed to determine if the increased costs associated with these designs are justified by the improved safety which they provide. (orig.)

  5. Intermittent degradation and schizotypy

    Directory of Open Access Journals (Sweden)

    Matthew W. Roché

    2015-06-01

    Full Text Available Intermittent degradation refers to transient detrimental disruptions in task performance. This phenomenon has been repeatedly observed in the performance data of patients with schizophrenia. Whether intermittent degradation is a feature of the liability for schizophrenia (i.e., schizotypy is an open question. Further, the specificity of intermittent degradation to schizotypy has yet to be investigated. To address these questions, 92 undergraduate participants completed a battery of self-report questionnaires assessing schizotypy and psychological state variables (e.g., anxiety, depression, and their reaction times were recorded as they did so. Intermittent degradation was defined as the number of times a subject’s reaction time for questionnaire items met or exceeded three standard deviations from his or her mean reaction time after controlling for each item’s information processing load. Intermittent degradation scores were correlated with questionnaire scores. Our results indicate that intermittent degradation is associated with total scores on measures of positive and disorganized schizotypy, but unrelated to total scores on measures of negative schizotypy and psychological state variables. Intermittent degradation is interpreted as potentially derivative of schizotypy and a candidate endophenotypic marker worthy of continued research.

  6. Comparative assessment of alternative cycles for waste heat recovery and upgrade

    International Nuclear Information System (INIS)

    Little, Adrienne B.; Garimella, Srinivas

    2011-01-01

    Thermally activated systems based on sorption cycles, as well as mechanical systems based on vapor compression/expansion are assessed in this study for waste heat recovery applications. In particular, ammonia-water sorption cycles for cooling and mechanical work recovery, a heat transformer using lithium bromide-water as the working fluid pair to yield high temperature heat, and organic Rankine cycles using refrigerant R245fa for work recovery as well as versions directly coupled to a vapor compression cycle to yield cooling are analyzed with overall heat transfer conductances for heat exchangers that use similar approach temperature differences for each cycle. Two representative cases are considered, one for smaller-scale and lower temperature applications using waste heat at 60 o C, and the other for larger-scale and higher temperature waste heat at 120 o C. Comparative assessments of these cycles on the basis of efficiencies and system footprints guide the selection of waste heat recovery and upgrade systems for different applications and waste heat availabilities. Furthermore, these considerations are used to investigate four case studies for waste heat recovery for data centers, vehicles, and process plants, illustrating the utility and limitations of such solutions. The increased implementation of such waste heat recovery systems in a variety of applications will lead to decreased primary source inputs and sustainable energy utilization. -- Highlights: → Sorption and mechanical pathways for the conversion of waste heat streams to work, cooling, and temperature boosting were investigated. → Waste heat sources including 300 W of energy at 60 o C and 1 kW of energy at 120 o C were analyzed. → Up to about seventy percent of the input waste heat can be converted to cooling. → Up to about ten percent can be converted to work. → Up to about 47 percent can be upgraded to a higher temperature.

  7. Intermittent Explosive Disorder

    Directory of Open Access Journals (Sweden)

    Lut Tamam

    2011-09-01

    Full Text Available Intermittent explosive disorder is an impulse control disorder characterized by the occurrence of discrete episodes of failure to resist aggressive impulses that result in violent assault or destruction of property. Though the prevalence intermittent explosive disorder has been reported to be relatively rare in frontier studies on the field, it is now common opinion that intermittent explosive disorder is far more common than previously thought especially in clinical psychiatry settings. Etiological studies displayed the role of both psychosocial factors like childhood traumas and biological factors like dysfunctional neurotransmitter systems and genetics. In differential diagnosis of the disorder, disorders involving agression as a symptom such as alcohol and drug intoxication, antisocial and borderline personality disorders, personality changes due to general medical conditions and behavioral disorder should be considered. A combination of pharmacological and psychotherapeutic approaches are suggested in the treatment of the disorder. This article briefly reviews the historical background, diagnostic criteria, epidemiology, etiology and treatment of intermittent explosive disorder.

  8. Naftidrofuryl for intermittent claudication.

    Science.gov (United States)

    De Backer, T L M; Vander Stichele, R; Lehert, P; Van Bortel, L

    2008-04-16

    Lifestyle changes and cardiovascular prevention measures are a primary treatment for intermittent claudication (IC). Symptomatic treatment with vasoactive agents (Anatomic Therapeutic Chemical Classification (ATC) for medicines from the World Health Organisation class CO4A) is controversial. To evaluate evidence on the efficacy and safety of oral naftidrofuryl (ATC CO4 21) versus placebo on the pain-free walking distance (PFWD) of people with IC by using a meta-analysis based on individual patient data (IPD). The Cochrane Peripheral Vascular Diseases Group searched their Trials Register (last searched December 2007) and CENTRAL (last searched 2007, Issue 4). We searched MEDLINE, EMBASE, International Pharmaceutical Abstracts, the Science Citation Index and contacted the authors and checked the reference lists of retrieved articles. We asked the manufacturing company for IPD. We included only randomized controlled trials (RCTs) with low or moderate risk of bias for which the IPD were available. We collected data from the electronic data file or from the case report form and checked the data by a statistical quality control procedure. All randomized patients were analyzed following the intention-to-treat (ITT) principle. The geometric mean of the relative improvement in PFWD was calculated for both treatment groups in all identified studies. The effect of the drug was assessed compared with placebo on final walking distance (WDf) using multilevel and random-effect models and adjusting for baseline walking distance (WD0). For the responder analysis, therapeutic success was defined as an improvement of walking distance of at least 50%. We included seven studies in the IPD (n = 1266 patients). One of these studies (n = 183) was only used in the sensitivity analysis so that the main analysis included 1083 patients. The ratio of the relative improvement in PFWD (naftidrofuryl compared with placebo) was 1.37 (95% confidence interval (CI) 1.32 to 1.51, P < 0.001). The

  9. Intermittent versus Persistent Wolff-Parkinson-White Syndrome in Children: Electrophysiologic Properties and Clinical Outcomes.

    Science.gov (United States)

    Kiger, Michelle E; McCanta, Anthony C; Tong, Suhong; Schaffer, Michael; Runciman, Martin; Collins, Kathryn K

    2016-01-01

    Intermittent Wolff-Parkinson-White (WPW) syndrome is considered to have a lower risk of sudden death. Fewer data exist regarding electrophysiologic (EP) characteristics and the natural history of intermittent WPW in children. All patients with WPW age 1-18 years at a single institution (1996-2013) were reviewed. Patients with intermittent preexcitation were compared to those with loss of preexcitation on Holter/exercise testing and those with persistent preexcitation. High-risk accessory pathway (AP) was defined as AP effective refractory period (APERP), block cycle length, or shortest preexcited RR interval during atrial fibrillation ≤250 ms. A total of 295 patients were included: 226 (76.6%) persistent, 39 (13.2%) intermittent, and 30 (10.2%) loss of preexcitation Holter/exercise. There were no differences in symptoms between groups. Median interquartile range APERP was significantly longer in intermittent WPW (380 [320, 488] ms vs 320 [300, 350] ms persistent, 310 [290, 330] ms loss of preexcitation Holter/exercise; P = 0.0008). At baseline, there was no difference between groups in frequency of high-risk pathways. However, when isoproterenol values were included, high-risk pathways were more frequent among patients with loss of preexcitation on Holter/exercise (54% vs 16% persistent, 11% intermittent; P = 0.005). There was one death in a patient with loss of preexcitation on exercise testing, no EP study, and prior drug use. A second patient with persistent WPW and APERP 270 ms required resuscitation following a methadone overdose. Intermittent preexcitation in children does not connote a lower risk AP by EP criteria or reduced symptoms. The low number of pediatric WPW patients who develop preexcited atrial fibrillation or sudden death warrants larger studies to investigate these outcomes. ©2015 Wiley Periodicals, Inc.

  10. Optimal intermittent search strategies

    International Nuclear Information System (INIS)

    Rojo, F; Budde, C E; Wio, H S

    2009-01-01

    We study the search kinetics of a single fixed target by a set of searchers performing an intermittent random walk, jumping between different internal states. Exploiting concepts of multi-state and continuous-time random walks we have calculated the survival probability of a target up to time t, and have 'optimized' (minimized) it with regard to the transition probability among internal states. Our model shows that intermittent strategies always improve target detection, even for simple diffusion states of motion

  11. Intermittent hypoxia increases melanoma metastasis to the lung in a mouse model of sleep apnea.

    Science.gov (United States)

    Almendros, Isaac; Montserrat, Josep M; Torres, Marta; Dalmases, Mireia; Cabañas, Maria L; Campos-Rodríguez, Francisco; Navajas, Daniel; Farré, Ramon

    2013-05-01

    Obstructive sleep apnea (OSA) has recently been associated with an increased risk of cancer incidence and mortality in humans. Experimental data in mice have also shown that intermittent hypoxia similar to that observed in OSA patients enhances tumor growth. The aim of this study was to test the hypothesis that intermittent hypoxia mimicking OSA enhances lung metastasis. A total of 75 C57BL/6J male mice (10-week-old) were subjected to either spontaneous or induced melanoma lung metastasis. Normoxic animals breathed room air and intermittent hypoxic animals were subjected to cycles of 20s of 5% O2 followed by 40s of room air for 6h/day. Spontaneous and induced lung metastases were studied after subcutaneous and intravenous injection of B16F10 melanoma cells, respectively. Compared with normoxia, intermittent hypoxia induced a significant increase in melanoma lung metastasis. These animal model results suggest that intermittent hypoxia could contribute to cancer metastasis in patients with OSA. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Chronic intermittent hypoxia preserves bone density in a mouse model of sleep apnea.

    Science.gov (United States)

    Torres, Marta; Montserrat, Josep M; Pavía, Javier; Dalmases, Mireia; Ros, Domenec; Fernandez, Yolanda; Barbé, Ferran; Navajas, Daniel; Farré, Ramon

    2013-12-01

    Very recent clinical research has investigated whether obstructive sleep apnea (OSA) may modulate bone homeostasis but the few data available are conflicting. Here we report novel data obtained in a mouse study specifically designed to determine whether chronic intermittent hypoxia realistically mimicking OSA modifies bone mineral density (BMD). Normal male and female mice and orchidectomized mice (N=10 each group) were subjected to a pattern of high-frequency intermittent hypoxia (20s at 5% and 40s at 21%, 60 cycles/h) for 6h/day. Identical groups breathing room air (normoxia) were the controls. After 32 days of intermittent hypoxia/normoxia the trabecular bone mineral density (BMD) in the peripheral femora were measured by micro-CT scanning. When compared with normoxia (two-way ANOVA), intermittent hypoxia did not significantly modify BMD in the three animal groups tested. Data in this study suggest that the type of intermittent hypoxia characterizing OSA, applied as a single challenge, preserves bone homeostasis. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. A comparative study of cell cycle mediator protein expression patterns in anaplastic and papillary thyroid carcinoma.

    Science.gov (United States)

    Evans, Juanita J; Crist, Henry S; Durvesh, Saima; Bruggeman, Richard D; Goldenberg, David

    2012-07-01

    Anaplastic thyroid carcinoma (ATC) is an extremely aggressive and rapidly fatal neoplasm. The aim of this study was to identify a limited cell cycle associated protein expression pattern unique to ATC and to correlate that pattern with clinical outcome. This represents one of the largest tissue micro-array projects comparing the cell cycle protein expression data of ATC to other well-differentiated tumors in the literature. Tissue microarrays were created from 21 patients with ATC and an age and gender matched cohort of patients with papillary thyroid carcinoma (PTC). Expression of epidermal growth factor receptor, cyclin D1, cyclin E, p53, p21, p16, aurora kinase A, opioid growth factor (OGF), OGF-receptor, thyroglobulin and Ki-67 was evaluated in a semi-quantitative fashion. Differences in protein expression between the cohorts were evaluated using chi-square tests with Bonferroni adjustments. Survival time and presence of metastasis at presentation were collected. The ATC cohort showed a statistically significant decrease (p cycle with aberrant expression of multiple protein markers suggesting increased proliferative activity and loss of control of cell cycle progression to G₁ phase. These findings support the assertion that ATC may represent the furthest end of a continuum of thyroid carcinoma dedifferentiation.

  14. A randomized trial comparing part-time patching with observation for children 3 to 10 years of age with intermittent exotropia.

    Science.gov (United States)

    Cotter, Susan A; Mohney, Brian G; Chandler, Danielle L; Holmes, Jonathan M; Repka, Michael X; Melia, Michele; Wallace, David K; Beck, Roy W; Birch, Eileen E; Kraker, Raymond T; Tamkins, Susanna M; Miller, Aaron M; Sala, Nicholas A; Glaser, Stephen R

    2014-12-01

    To determine the effectiveness of prescribed part-time patching for treatment of intermittent exotropia (IXT) in children. Multicenter, randomized clinical trial. Three hundred fifty-eight children 3 to part-time patching group (difference, 5.4%; lower limit of 1-sided exact 95% confidence interval, 2.0%; P = 0.004, 1-sided hypothesis test). Deterioration of previously untreated childhood IXT over a 6-month period is uncommon with or without patching treatment. Although there is a slightly lower deterioration rate with patching, both management approaches are reasonable for treating children 3 to 10 years of age with IXT. Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  15. High-power electronics thermal management with intermittent multijet sprays

    International Nuclear Information System (INIS)

    Panão, Miguel R.O.; Correia, André M.; Moreira, António L.N.

    2012-01-01

    Thermal management plays a crucial role in the development of high-power electronics devices, e.g. in electric vehicles. The greatest energy demands occur during power peaks, implying dynamic thermal losses within the vehicle’s driving cycle. Therefore, the need for devising intelligent thermal management systems able to efficiently respond to these power peaks has become a technological challenge. Experiments have been performed with methanol in order to quantify the maximum heat flux removed by a multijet spray to keep the 4 cm 2 surface temperature stabilized and below the threshold of 125 °C. A multijet atomization strategy consists in producing a spray through the multiple and simultaneous impact of N j cylindrical jets. Moreover, the spray intermittency is expressed through the duty cycle (DC), which depends on the frequency and duration of injection. Results evidence that: i) a shorter time between consecutive injection cycles enables a better distribution of the mass flow rate, resulting in larger heat transfer coefficient values, as well as higher cooling efficiencies; ii) compared with continuous sprays, the analysis evidences that an intermittent spray allows benefiting more from phase-change convection. Moreover, the mass flux is mainly affecting heat transfer rather than differences induced in the spray structure by using different multijet configurations. - Highlights: ► Intermittent spray cooling (ISC) is advantageous for intelligent thermal management. ► Distributing the mass flow rate through ISC improves heat transfer. ► Multijet sprays with increasing number of jets have higher heat transfer rates. ► ISC with multijet sprays benefit more from phase-change than continuous sprays.

  16. A comparative assessment of the economics of plutonium disposition including comparison with other nuclear fuel cycles

    International Nuclear Information System (INIS)

    Williams, K.A.; Miller, J.W.; Reid, R.L.

    1997-01-01

    DOE has been evaluating three technologies for the disposition of approximately 50 metric tons of surplus plutonium from defense-related programs: reactors, immobilization, and deep boreholes. As part of the process supporting an early CY 1997 Record of Decision (ROD), a comprehensive assessment of technical viability, cost, and schedule has been conducted. Oak Ridge National Laboratory has managed and coordinated the life-cycle cost (LCC) assessment effort for this program. This paper discusses the economic analysis methodology and the results prior to ROD. Other objectives of the paper are to discuss major technical and economic issues that impact plutonium disposition cost and schedule. Also to compare the economics of a once-through weapons-derived MOX nuclear fuel cycle to other fuel cycles, such as those utilizing spent fuel reprocessing. To evaluate the economics of these technologies on an equitable basis, a set of cost estimating guidelines and a common cost-estimating format were utilized by all three technology teams. This paper also includes the major economic analysis assumptions and the comparative constant-dollar and discounted-dollar LCCs

  17. Testes de broncoprovocação com metacolina e com exercício em bicicleta e corrida livre em crianças com asma intermitente Bronchial provocation tests using methacholine, cycle ergometer exercise and free running in children with intermittent asthma

    Directory of Open Access Journals (Sweden)

    Ana C. T. G. Souza

    2005-02-01

    Full Text Available OBJETIVO: Comparar a responsividade de vias aéreas à metacolina e ao teste de exercício na bicicleta ergométrica e corrida livre em crianças com asma intermitente. MÉTODOS: Estudo randomizado. Trinta crianças de ambos os sexos com asma intermitente participaram do estudo. Cada teste foi realizado em 3 dias diferentes, através de randomização: a broncoprovocação com metacolina, método do dosímetro; b teste de exercício: corrida livre em um corredor de 50 m; c teste de exercício: bicicleta ergométrica com ar seco. A freqüência cardíaca atingida foi 80 a 90% da freqüência cardíaca máxima. A espirometria foi realizada aos 3, 6, 10, 15, 20 e 30 minutos após o exercício. Broncoespasmo induzido por exercício foi definido como a queda de volume expiratório forçado no primeiro segundo (VEF1 > 10% em relação aos valores pré-teste. RESULTADOS: A média de idade foi 11±3 anos. O VEF1 e VEF1/CVF (capacidade vital forçada foram normais e similares antes dos três testes de broncoprovocação. A freqüência cardíaca máxima foi de 178±7 bpm durante o exercício na bicicleta e 181±6 bpm na corrida livre (p > 0,05. Broncoespasmo significante foi visto em 23 crianças após o teste com metacolina, em 19 após a corrida livre e em 14 crianças após exercício em bicicleta (p OBJECTIVE: To compare airway responsiveness to methacholine, cycle ergometer exercise and free running in children with intermittent asthma. METHODS: A randomized study was conducted with 30 children of both genders with intermittent asthma. Each child was submitted to challenge testing on three separate days, in random order: a Methacholine challenge using a dosimeter; b Exercise challenge testing - free running along a 50-meter-long corridor; c Dry-air exercise challenge on a cycle ergometer. Target heart rate during exercise was 80 to 90% of the maximum predicted value. Spirometry was performed 3, 6,10,15,20 and 30 minutes after exercise. Exercise

  18. Unsteady propulsion by an intermittent swimming gait

    Science.gov (United States)

    Akoz, Emre; Moored, Keith W.

    2018-01-01

    Inviscid computational results are presented on a self-propelled swimmer modeled as a virtual body combined with a two-dimensional hydrofoil pitching intermittently about its leading edge. Lighthill (1971) originally proposed that this burst-and-coast behavior can save fish energy during swimming by taking advantage of the viscous Bone-Lighthill boundary layer thinning mechanism. Here, an additional inviscid Garrick mechanism is discovered that allows swimmers to control the ratio of their added mass thrust-producing forces to their circulatory drag-inducing forces by decreasing their duty cycle, DC, of locomotion. This mechanism can save intermittent swimmers as much as 60% of the energy it takes to swim continuously at the same speed. The inviscid energy savings are shown to increase with increasing amplitude of motion, increase with decreasing Lighthill number, Li, and switch to an energetic cost above continuous swimming for sufficiently low DC. Intermittent swimmers are observed to shed four vortices per cycle that form into groups that are self-similar with the DC. In addition, previous thrust and power scaling laws of continuous self-propelled swimming are further generalized to include intermittent swimming. The key is that by averaging the thrust and power coefficients over only the bursting period then the intermittent problem can be transformed into a continuous one. Furthermore, the intermittent thrust and power scaling relations are extended to predict the mean speed and cost of transport of swimmers. By tuning a few coefficients with a handful of simulations these self-propelled relations can become predictive. In the current study, the mean speed and cost of transport are predicted to within 3% and 18% of their full-scale values by using these relations.

  19. Comparative Life Cycle Assessment of Lignocellulosic Ethanol Production: Biochemical Versus Thermochemical Conversion

    Science.gov (United States)

    Mu, Dongyan; Seager, Thomas; Rao, P. Suresh; Zhao, Fu

    2010-10-01

    Lignocellulosic biomass can be converted into ethanol through either biochemical or thermochemical conversion processes. Biochemical conversion involves hydrolysis and fermentation while thermochemical conversion involves gasification and catalytic synthesis. Even though these routes produce comparable amounts of ethanol and have similar energy efficiency at the plant level, little is known about their relative environmental performance from a life cycle perspective. Especially, the indirect impacts, i.e. emissions and resource consumption associated with the production of various process inputs, are largely neglected in previous studies. This article compiles material and energy flow data from process simulation models to develop life cycle inventory and compares the fossil fuel consumption, greenhouse gas emissions, and water consumption of both biomass-to-ethanol production processes. The results are presented in terms of contributions from feedstock, direct, indirect, and co-product credits for four representative biomass feedstocks i.e., wood chips, corn stover, waste paper, and wheat straw. To explore the potentials of the two conversion pathways, different technological scenarios are modeled, including current, 2012 and 2020 technology targets, as well as different production/co-production configurations. The modeling results suggest that biochemical conversion has slightly better performance on greenhouse gas emission and fossil fuel consumption, but that thermochemical conversion has significantly less direct, indirect, and life cycle water consumption. Also, if the thermochemical plant operates as a biorefinery with mixed alcohol co-products separated for chemicals, it has the potential to achieve better performance than biochemical pathway across all environmental impact categories considered due to higher co-product credits associated with chemicals being displaced. The results from this work serve as a starting point for developing full life cycle

  20. Comparative life cycle assessment (LCA) of biodiesel and fossil diesel fuel

    International Nuclear Information System (INIS)

    Spirinckx, C.; Xeuterick, D.

    1997-01-01

    Complementary to VlTO's demonstration project on the use of biodiesel as engine fuel (including on the road emission measurements) in Flanders, Belgium, a comparative life cycle assessment (LCA) has been carried out for rapeseed methyl ester (RME) and fossil diesel fuel. The primary concern of this study is the question as to whether or not the production of biodiesel is comparable to the production of fossil diesel fuel from an environmental point of view, taking into account all stages of the life cycle of these two products. The study covers: (1) a description of the LCA methodology used; (2) a definition of the goal and scope of the study: (3) an inventory of the consumption of energy and materials and the discharges to the environment, from the cradle to the grave, for both alternative fuels: (4) a comparative impact assessment; and (5) the interpretation of the results. The results of this comparative LCA can be used in the final decision making process next to the results of a social and economical assessment. 6 refs

  1. Comparative study of the antitumor effect of natural monoterpenes: relationship to cell cycle analysis

    Directory of Open Access Journals (Sweden)

    Abdeslam Jaafari

    2012-06-01

    Full Text Available Monoterpenes have been identified as responsible of important therapeutic effects of plant-extracts. In this work, we try to compare the cytotoxic effect of six monoterpenes (carvacrol, thymol, carveol, carvone, eugenol and isopulegol as well as their molecular mechanisms. The in vitro antitumor activity of the tested products, evaluated against five tumor cell lines, show that the carvacrol is the most cytotoxic monoterpene. The investigation of an eventual synergistic effect of the six natural monoterpenes with two anticancer drugs revealed that there is a significant synergy between them (p<5%. On the other hand, the effect of the tested products on cell cycle progression was examined by flow cytometry after DNA staining in order to investigate the molecular mechanism of their cytotoxic activity. The results revealed that carvacrol and carveol stopped the cell cycle progression in S phase; however, thymol and isopulegol stopped it in G0/G1 phase. Regarding carvone and eugenol, no effect on cell cycle was observed.

  2. Life cycle assessments of urban water systems: a comparative analysis of selected peer-reviewed literature.

    Science.gov (United States)

    Loubet, Philippe; Roux, Philippe; Loiseau, Eleonore; Bellon-Maurel, Veronique

    2014-12-15

    Water is a growing concern in cities, and its sustainable management is very complex. Life cycle assessment (LCA) has been increasingly used to assess the environmental impacts of water technologies during the last 20 years. This review aims at compiling all LCA papers related to water technologies, out of which 18 LCA studies deals with whole urban water systems (UWS). A focus is carried out on these 18 case studies which are analyzed according to criteria derived from the four phases of LCA international standards. The results show that whereas the case studies share a common goal, i.e., providing quantitative information to policy makers on the environmental impacts of urban water systems and their forecasting scenarios, they are based on different scopes, resulting in the selection of different functional units and system boundaries. A quantitative comparison of life cycle inventory and life cycle impact assessment data is provided, and the results are discussed. It shows the superiority of information offered by multi-criteria approaches for decision making compared to that derived from mono-criterion. From this review, recommendations on the way to conduct the environmental assessment of urban water systems are given, e.g., the need to provide consistent mass balances in terms of emissions and water flows. Remaining challenges for urban water system LCAs are identified, such as a better consideration of water users and resources and the inclusion of recent LCA developments (territorial approaches and water-related impacts). Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Anti-bacterial activity of intermittent preventive treatment of malaria in pregnancy: comparative in vitro study of sulphadoxine-pyrimethamine, mefloquine, and azithromycin

    Directory of Open Access Journals (Sweden)

    Mombo-Ngoma Ghyslain

    2010-10-01

    Full Text Available Abstract Background Intermittent preventive treatment of malaria with sulphadoxine-pyrimethamine (SP is recommended for the prevention of malaria in pregnancy in sub-Saharan Africa. Increasing drug resistance necessitates the urgent evaluation of alternative drugs. Currently, the most promising candidates in clinical development are mefloquine and azithromycin. Besides the anti-malarial activity, SP is also a potent antibiotic and incurs significant anti-microbial activity when given as IPTp - though systematic clinical evaluation of this action is still lacking. Methods In this study, the intrinsic anti-bacterial activity of mefloquine and azithromycin was assessed in comparison to sulphadoxine-pyrimethamine against bacterial pathogens with clinical importance in pregnancy in a standard microdilution assay. Results SP was highly active against Staphylococcus aureus and Streptococcus pneumoniae. All tested Gram-positive bacteria, except Enterococcus faecalis, were sensitive to azithromycin. Additionally, azithromycin was active against Neisseria gonorrhoeae. Mefloquine showed good activity against pneumococci but lower in vitro action against all other tested pathogens. Conclusion These data indicate important differences in the spectrum of anti-bacterial activity for the evaluated anti-malarial drugs. Given the large scale use of IPTp in Africa, the need for prospective clinical trials evaluating the impact of antibiotic activity of anti-malarials on maternal and foetal health and on the risk of promoting specific drug resistance of bacterial pathogens is discussed.

  4. Blastocyst transfer does not improve cycle outcome as compared to D3 transfer in antagonist cycles with an elevated progesterone level on the day of hCG.

    Science.gov (United States)

    Demirel, Cem; Aydoğdu, Serkan; Özdemir, Arzu İlknur; Keskin, Gülşah; Baştu, Ercan; Buyru, Faruk

    2017-09-01

    To evaluate the association between progesterone elevation on the day of human chorionic gonadotropin (hCG) administration and clinical pregnancy rates of gonadotropin-releasing hormone (GnRH) antagonist in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles with the transfer of embryos at different developmental stages (day-3 versus day-5 ETs). This is a retrospective analysis of fresh IVF/ICSI; 194 cycles out of 2676 conducted in a single center. A total of 2676 cycles were analyzed, of which 386 had no progesterone measurements available. Two hundred eighteen cycles had progesterone elevation (p>1.5 ng/mL) giving an overall incidence of 9.5%. Twenty-four cycles were excluded from further analysis. Of the remaining 194 cycles, 151 had day-3 transfers and 43 had blastocyst transfers. There was no statistically significant difference in pregnancy and clinical pregnancy rates per transfer between the D3-ET and D5-ET groups (46% vs. 49%, and 39% vs. 35%, respectively). The results of this study suggest that blastocyst transfer does not improve cycle outcomes compared with D3 transfer in GnRH antagonist cycles with an elevated progesterone level on the day of hCG.

  5. Optimal intermittent search strategies

    Energy Technology Data Exchange (ETDEWEB)

    Rojo, F; Budde, C E [FaMAF, Universidad Nacional de Cordoba, Ciudad Universitaria, X5000HUA Cordoba (Argentina); Wio, H S [Instituto de Fisica de Cantabria, Universidad de Cantabria and CSIC E-39005 Santander (Spain)

    2009-03-27

    We study the search kinetics of a single fixed target by a set of searchers performing an intermittent random walk, jumping between different internal states. Exploiting concepts of multi-state and continuous-time random walks we have calculated the survival probability of a target up to time t, and have 'optimized' (minimized) it with regard to the transition probability among internal states. Our model shows that intermittent strategies always improve target detection, even for simple diffusion states of motion.

  6. Intermittency and random matrices

    Science.gov (United States)

    Sokoloff, Dmitry; Illarionov, E. A.

    2015-08-01

    A spectacular phenomenon of intermittency, i.e. a progressive growth of higher statistical moments of a physical field excited by an instability in a random medium, attracted the attention of Zeldovich in the last years of his life. At that time, the mathematical aspects underlying the physical description of this phenomenon were still under development and relations between various findings in the field remained obscure. Contemporary results from the theory of the product of independent random matrices (the Furstenberg theory) allowed the elaboration of the phenomenon of intermittency in a systematic way. We consider applications of the Furstenberg theory to some problems in cosmology and dynamo theory.

  7. Conductive plastics: comparing alternative nanotechnologies by performance and life cycle release probability

    Energy Technology Data Exchange (ETDEWEB)

    Neubauer, Nicole; Wohlleben, Wendel, E-mail: wendel.wohlleben@basf.com [Material Physics, GMC/R, BASF SE (Germany); Tomović, Željko, E-mail: zeljko.tomovic@basf.com [BASF Polyurethanes GmbH, GMP/LS (Germany)

    2017-03-15

    Nanocomposites can be considered safe during their life cycle as long as the nanofillers remain embedded in the matrix. Therefore, a possible release of nanofillers has to be assessed before commercialization. This report addresses possible life cycle release scenarios for carbon nanotubes (CNT), graphene, and carbon black (CB) from a thermoplastic polyurethane (TPU) matrix. The content of each nanofiller was adjusted to achieve the same conductivity level. The nanofillers reduced the rate of nanoscale releases during mechanical processing with decreasing release in the order neat TPU, TPU-CNT, TPU-graphene, and TPU-CB. Released fragments were dominated by the polymer matrix with embedded or surface-protruding nanofillers. During electron microscopy analysis, free CB was observed, however, there was no free CNT or graphene. Quantitatively, the presence of free nanofillers remained below the detection limit of <0.01% of generated dust. Further, both the production process and type of mechanical processing showed a significant impact with higher release rates for injection-molded compared to extruded and sanded compared to drilled materials. Due to its optimal performance for further development, extruded TPU-CNT was investigated in a combined, stepwise worst case scenario (mechanical processing after weathering). After weathering by simulated sunlight and rain, CNT were visible at the surface of the nanocomposite; after additional sanding, fragments showed protruding CNT, but free CNT were not detected. In summary, this preliminary exposure assessment showed no indication that recommended occupational exposure limits for carbonaceous nanomaterials can be exceeded during the life cycle of the specific TPU nanocomposites and conditions investigated in this study.

  8. Comparative life-cycle assessment of a small wind turbine for residential off-grid use

    International Nuclear Information System (INIS)

    Fleck, Brian; Huot, Marc

    2009-01-01

    As the popularity of renewable energy systems grows, small wind turbines are becoming a common choice for off-grid household power. However, the true benefits of such systems over the traditional internal combustion systems are unclear. This study employs a life-cycle assessment methodology in order to directly compare the environmental impacts, net-energy inputs, and life-cycle cost of two systems: a stand-alone small wind turbine system and a single-home diesel generator system. The primary focus for the investigation is the emission of greenhouse gases (GHG) including CO 2 , CH 4 , and N 2 O. These emissions are calculated over the life-cycle of the two systems which provide the same amount of energy to a small off-grid home over a twenty-year period. The results show a considerable environmental benefit for small-scale wind power. The wind generator system offered a 93% reduction of GHG emissions when compared to the diesel system. Furthermore, the diesel generator net-energy input was over 200 MW, while the wind system produced an electrical energy output greater than its net-energy input. Economically, the conclusions were less clear. The assumption was made that diesel fuel cost over the next twenty years was based on May 2008 prices, increasing only in proportion to inflation. As such, the net-present cost of the wind turbine system was 14% greater than the diesel system. However, a larger model wind turbine would likely benefit from the effects of the 'economy of scale,' producing superior results both economically and environmentally. (author)

  9. The effects of Red Bull energy drink compared with caffeine on cycling time-trial performance.

    Science.gov (United States)

    Quinlivan, Alannah; Irwin, Christopher; Grant, Gary D; Anoopkumar-Dukie, Sheilandra; Skinner, Tina; Leveritt, Michael; Desbrow, Ben

    2015-10-01

    This study investigated the ergogenic effects of a commercial energy drink (Red Bull) or an equivalent dose of anhydrous caffeine in comparison with a noncaffeinated control beverage on cycling performance. Eleven trained male cyclists (31.7 ± 5.9 y 82.3 ± 6.1 kg, VO2max = 60.3 ± 7.8 mL · kg-1 · min-1) participated in a double-blind, placebo-controlled, crossover-design study involving 3 experimental conditions. Participants were randomly administered Red Bull (9.4 mL/kg body mass [BM] containing 3 mg/kg BM caffeine), anhydrous caffeine (3 mg/kg BM given in capsule form), or a placebo 90 min before commencing a time trial equivalent to 1 h cycling at 75% peak power output. Carbohydrate and fluid volumes were matched across all trials. Performance improved by 109 ± 153 s (2.8%, P = .039) after Red Bull compared with placebo and by 120 ± 172 s (3.1%, P = .043) after caffeine compared with placebo. No significant difference (P > .05) in performance time was detected between Red Bull and caffeine treatments. There was no significant difference (P > .05) in mean heart rate or rating of perceived exertion among the 3 treatments. This study demonstrated that a moderate dose of caffeine consumed as either Red Bull or in anhydrous form enhanced cycling time-trial performance. The ergogenic benefits of Red Bull energy drink are therefore most likely due to the effects of caffeine, with the other ingredients not likely to offer additional benefit.

  10. Life Cycle Greenhouse Gas Emissions from Electricity Generation: A Comparative Analysis of Australian Energy Sources

    Directory of Open Access Journals (Sweden)

    Robert G. Hynes

    2012-03-01

    Full Text Available Electricity generation is one of the major contributors to global greenhouse gas emissions. Transitioning the World’s energy economy to a lower carbon future will require significant investment in a variety of cleaner technologies, including renewables and nuclear power. In the short term, improving the efficiency of fossil fuel combustion in energy generation can provide an important contribution. Availability of life cycle GHG intensity data will allow decision-makers to move away from overly simplistic assertions about the relative merits of certain fuels, and focus on the complete picture, especially the critical roles of technology selection and application of best practice. This analysis compares the life-cycle greenhouse gas (GHG intensities per megawatt-hour (MWh of electricity produced for a range of Australian and other energy sources, including coal, conventional liquefied natural gas (LNG, coal seam gas LNG, nuclear and renewables, for the Australian export market. When Australian fossil fuels are exported to China, life cycle greenhouse gas emission intensity in electricity production depends to a significant degree on the technology used in combustion. LNG in general is less GHG intensive than black coal, but the gap is smaller for gas combusted in open cycle gas turbine plant (OCGT and for LNG derived from coal seam gas (CSG. On average, conventional LNG burned in a conventional OCGT plant is approximately 38% less GHG intensive over its life cycle than black coal burned in a sub-critical plant, per MWh of electricity produced. However, if OCGT LNG combustion is compared to the most efficient new ultra-supercritical coal power, the GHG intensity gap narrows considerably. Coal seam gas LNG is approximately 13–20% more GHG intensive across its life cycle, on a like-for like basis, than conventional LNG. Upstream fugitive emissions from CSG (assuming best practice gas extraction techniques do not materially alter the life cycle

  11. Human Impacts on the Hydrologic Cycle: Comparing Global Climate Change and Local Water Management

    Science.gov (United States)

    Ferguson, I. M.; Maxwell, R. M.

    2010-12-01

    Anthropogenic climate change is significantly altering the hydrologic cycle at global and regional scales, with potentially devastating impacts on water resources. Recent studies demonstrate that hydrologic response to climate change will depend on local-scale feedbacks between groundwater, surface water, and land surface processes. These studies suggest that local water management practices that alter the quantity and distribution of water in the terrestrial system—e.g., groundwater pumping and irrigation—may also feed back across the hydrologic cycle, with impacts on land-atmosphere fluxes and thus weather and climate. Here we use an integrated hydrologic model to compare the impacts of large-scale climate change and local water management practices on water and energy budgets at local and watershed scales. We consider three climate scenarios (hot, hot+wet, and hot+dry) and three management scenarios (pumping only, irrigation only, and pumping+irrigation). Results demonstrate that impacts of local water management on basin-integrated groundwater storage, evapotranspiration, and stream discharge are comparable to those of changing climate conditions. However, impacts of climate change are shown to have a smaller magnitude and greater spatial extent, while impacts of pumping and irrigation are shown to have a greater magnitude but are local to areas where pumping and irrigation occur. These results have important implications regarding the scales of human impacts on both water resources and climate and the sustainability of water resources.

  12. [Comparative life cycle environmental assessment between electric taxi and gasoline taxi in Beijing].

    Science.gov (United States)

    Shi, Xiao-Qing; Sun, Zhao-Xin; Li, Xiao-Nuo; Li, Jin-Xiang; Yang, Jian-Xin

    2015-03-01

    Tailpipe emission of internal combustion engine vehicle (ICEV) is one of the main sources leading to atmospheric environmental problems such as haze. Substituting electric vehicles for conventional gasoline vehicles is an important solution for reducing urban air pollution. In 2011, as a pilot city of electric vehicle, Beijing launched a promotion plan of electric vehicle. In order to compare the environmental impacts between Midi electric vehicle (Midi EV) and Hyundai gasoline taxi (ICEV), this study created an inventory with local data and well-reasoned assumptions, and contributed a life cycle assessment (LCA) model with GaBi4.4 software and comparative life cycle environmental assessment by Life cycle impact analysis models of CML2001(Problem oriented) and EI99 (Damage oriented), which included the environmental impacts of full life cycle, manufacture phase, use phase and end of life. The sensitivity analysis of lifetime mileage and power structure was also provided. The results indicated that the full life cycle environmental impact of Midi EV was smaller than Hyundai ICEV, which was mainly due to the lower fossil fuel consumption. On the contrary, Midi EV exhibited the potential of increasing the environmental impacts of ecosystem quality influence and Human health influence. By CML2001 model, the results indicated that Midi EV might decrease the impact of Abiotic Depletion Potential, Global Warming Potential, Ozone Layer Depletion Potential and so on. However, in the production phase, the impact of Abiotic Depletion Potential, Acidification Potential, Eutrophication Potential, Global Warming Potential, Photochemical Ozone Creation Potential, Ozone Layer Depletion Potential, Marine Aquatic Ecotoxicity Potential, Terrestric Ecotoxicity Potential, Human Toxicity Potential of Midi EV were increased relative to Hyundai ICEV because of emissions impacts from its power system especially the battery production. Besides, in the use phase, electricity production was

  13. Incorporating comparative genomics into the design-test-learn cycle of microbial strain engineering.

    Science.gov (United States)

    Sardi, Maria; Gasch, Audrey P

    2017-08-01

    Engineering microbes with new properties is an important goal in industrial engineering, to establish biological factories for production of biofuels, commodity chemicals and pharmaceutics. But engineering microbes to produce new compounds with high yield remains a major challenge toward economically viable production. Incorporating several modern approaches, including synthetic and systems biology, metabolic modeling and regulatory rewiring, has proven to significantly advance industrial strain engineering. This review highlights how comparative genomics can also facilitate strain engineering, by identifying novel genes and pathways, regulatory mechanisms and genetic background effects for engineering. We discuss how incorporating comparative genomics into the design-test-learn cycle of strain engineering can provide novel information that complements other engineering strategies. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Comparative simulation of Stirling and Sibling cycle cryocoolers with two codes

    International Nuclear Information System (INIS)

    Mitchell, M.P.; Wilson, K.J.; Bauwens, L.

    1989-01-01

    The authors present a comparative analysis of Stirling and Sibling Cycle cryocoolers conducted with two different computer simulation codes. One code (CRYOWEISS) performs an initial analysis on the assumption of isothermal conditions in the machines and adjusts that result with decoupled loss calculations. The other code (MS*2) models fluid flows and heat transfers more realistically but ignores significant loss mechanisms, including flow friction and heat conduction through the metal of the machines. Surprisingly, MS*2 is less optimistic about performance of all machines even though it ignores losses that are modelled by CRYOWEISS. Comparison between constant-bore Stirling and Sibling machines shows that their performance is generally comparable over a range of temperatures, pressures and operating speeds. No machine was consistently superior or inferior according to both codes over the whole range of conditions studied

  15. Randomized controlled trial comparing nasal intermittent positive pressure ventilation and nasal continuous positive airway pressure in premature infants after tracheal extubation

    Directory of Open Access Journals (Sweden)

    Daniela Franco Rizzo Komatsu

    Full Text Available Summary Objective: To analyze the frequency of extubation failure in premature infants using conventional mechanical ventilation (MV after extubation in groups subjected to nasal intermittent positive pressure ventilation (nIPPV and continuous positive airway pressure (nCPAP. Method: Seventy-two premature infants with respiratory failure were studied, with a gestational age (GA ≤ 36 weeks and birth weight (BW > 750 g, who required tracheal intubation and mechanical ventilation. The study was controlled and randomized in order to ensure that the members of the groups used in the research were chosen at random. Randomization was performed at the time of extubation using sealed envelopes. Extubation failure was defined as the need for re-intubation and mechanical ventilation during the first 72 hours after extubation. Results: Among the 36 premature infants randomized to nIPPV, six (16.6% presented extubation failure in comparison to 11 (30.5% of the 36 premature infants randomized to nCPAP. There was no statistical difference between the two study groups regarding BW, GA, classification of the premature infant, and MV time. The main cause of extubation failure was the occurrence of apnea. Gastrointestinal and neurological complications did not occur in the premature infants participating in the study. Conclusion: We found that, despite the extubation failure of the group of premature infants submitted to nIPPV being numerically smaller than in premature infants submitted to nCPAP, there was no statistically significant difference between the two modes of ventilatory support after extubation.

  16. Intermittent Testicular Torsion

    African Journals Online (AJOL)

    2017-06-02

    Jun 2, 2017 ... had prior episodes of testicular pain, suggesting that they may have had intermittent torsion before .... None of the patients had antecedent history of sexual exposure, fever, or urinary tract infection .... torsion of the spermatic cord portends an increased risk of acute testicular infarction. J Urol 2008;180 4 ...

  17. Effect of Intermittent Hypercapnia on Respiratory Control in Rat Pups

    Science.gov (United States)

    Steggerda, Justin A.; Mayer, Catherine A.; Martin, Richard J.; Wilson, Christopher G.

    2010-01-01

    Preterm infants are subject to fluctuations in blood gas status associated with immature respiratory control. Intermittent hypoxia during early postnatal life has been shown to increase chemoreceptor sensitivity and destabilize the breathing pattern; however, intermittent hypercapnia remains poorly studied. Therefore, to test the hypothesis that intermittent hypercapnia results in altered respiratory control, we examined the effects of daily exposure to intermittent hypercapnia on the ventilatory response to subsequent hypercapnic and hypoxic exposure in neonatal rat pups. Exposure cycles consisted of 5 min of intermittent hypercapnia (5% CO2, 21% O2, balance N2) followed by 10 min of normoxia. Rat pups were exposed to 18 exposure cycles each day for 1 week, from postnatal day 7 to 14. We analyzed diaphragm electromyograms (EMGs) from pups exposed to subsequent acute hypercapnic (5% CO2) and hypoxic (12% O2) challenges. In response to a subsequent hypercapnia challenge, there was no significant difference in the ventilatory response between control and intermittent hypercapnia-exposed groups. In contrast, intermittent hypercapnia-exposed rat pups showed an enhanced ventilatory response to hypoxic challenge with an increase in minute EMG to 118 ± 14% of baseline versus 107 ± 13% for control pups (p < 0.05). We speculate that prior hypercapnic exposure may increase peripheral chemoreceptor response to subsequent hypoxic exposures and result in perturbed neonatal respiratory control. PMID:19752577

  18. Comparative life cycle assessment of real pilot reactors for microalgae cultivation in different seasons

    International Nuclear Information System (INIS)

    Pérez-López, Paula; De Vree, Jeroen H.; Feijoo, Gumersindo; Bosma, Rouke; Barbosa, Maria J.; Moreira, María Teresa; Wijffels, René H.; Van Boxtel, Anton J.B.; Kleinegris, Dorinde M.M.

    2017-01-01

    Highlights: •Life cycle assessment was used to compare 3 real pilot systems for algae cultivation. •The temperature control system was the main contributor to environmental impacts. •Tubular reactors had lower impacts per unit of biomass produced than open pond. •Meteorological conditions on the reactors played a critical role in LCA results. •Environmental impact reductions of 17–90% were estimated for optimized full-scale reactors. -- Abstract: Microalgae are promising natural resources for biofuels, chemical, food and feed products. Besides their economic potential, the environmental sustainability must be examined. Cultivation has a significant environmental impact that depends on reactor selection and operating conditions. To identify the main environmental bottlenecks for scale-up to industrial facilities this study provides a comparative life cycle assessment (LCA) of open raceway ponds and tubular photobioreactors at pilot scale. The results are based on experimental data from real pilot plants operated in summer, fall and winter at AlgaePARC (Wageningen, The Netherlands). The energy consumption for temperature regulation presented the highest environmental burden. The production of nutrients affected some categories. Despite limited differences compared to the vertical system, the horizontal PBR was found the most efficient in terms of productivity and environmental impact. The ORP was, given the Dutch climatic conditions, only feasible under summer operation. The results highlight the relevance of LCA as a tool for decision-making in process design. Weather conditions and availability of sources for temperature regulation were identified as essential factors for the selection of geographic locations and for microalgal cultivation systems based on environmental criteria. Simulation of large-scale reactors with optimized temperature regulation systems lead to environmental improvements and energy demand reductions ranging from 17% up to 90% for

  19. Thermo-economic comparative analysis of gas turbine GT10 integrated with air and steam bottoming cycle

    Science.gov (United States)

    Czaja, Daniel; Chmielnak, Tadeusz; Lepszy, Sebastian

    2014-12-01

    A thermodynamic and economic analysis of a GT10 gas turbine integrated with the air bottoming cycle is presented. The results are compared to commercially available combined cycle power plants based on the same gas turbine. The systems under analysis have a better chance of competing with steam bottoming cycle configurations in a small range of the power output capacity. The aim of the calculations is to determine the final cost of electricity generated by the gas turbine air bottoming cycle based on a 25 MW GT10 gas turbine with the exhaust gas mass flow rate of about 80 kg/s. The article shows the results of thermodynamic optimization of the selection of the technological structure of gas turbine air bottoming cycle and of a comparative economic analysis. Quantities are determined that have a decisive impact on the considered units profitability and competitiveness compared to the popular technology based on the steam bottoming cycle. The ultimate quantity that can be compared in the calculations is the cost of 1 MWh of electricity. It should be noted that the systems analyzed herein are power plants where electricity is the only generated product. The performed calculations do not take account of any other (potential) revenues from the sale of energy origin certificates. Keywords: Gas turbine air bottoming cycle, Air bottoming cycle, Gas turbine, GT10

  20. Influence of the discount rate when comparing costs of different nuclear fuel cycles

    International Nuclear Information System (INIS)

    Le Dars, A.; Loaec, Ch.

    2007-01-01

    The article describes the methodology and technical economic results obtained by Cea in the DERECO project. This project was aimed at evaluating ground-breaking and intricate scenarios of the nuclear fuel cycle, and developed on the long term (150 years), in the context of France. All 5 scenarios studied assume that the reliance on nuclear energy will continue in order to satisfy the electricity demand. Despite uncertainties, the trends are breaking free from the analysis. It appears that the scenarios in which fourth generation fast reactors take part are globally more economical than the keeping to the present strategy of plutonium mono-recycling in PWR. The scenario in which fuel reprocessing is stopped has a total cost concerning the fuel cycle similar to that of the present strategy but the disposal cost is twice as high because of the necessity of disposing spent fuels directly in geological formations. The comparative costs of the different scenarios are set out and the influence of the discount rate is highlighted. One must keep in mind that the actualization theory entails a diminishing value for long term costs due to an unavoidable mechanical effect of the discount rate

  1. A Randomized Trial Comparing Part-time Patching with Observation for Intermittent Exotropia in Children 12 to 35 Months of Age.

    Science.gov (United States)

    Mohney, Brian G; Cotter, Susan A; Chandler, Danielle L; Holmes, Jonathan M; Chen, Angela M; Melia, Michele; Donahue, Sean P; Wallace, David K; Kraker, Raymond T; Christian, Melanie L; Suh, Donny W

    2015-08-01

    To determine the effectiveness of part-time patching for treating intermittent exotropia (IXT) in young children. Multicenter, randomized clinical trial. Two hundred one children 12 to 35 months of age with untreated IXT meeting the following criteria: (1) IXT at distance OR constant exotropia at distance and either IXT or exophoria at near, and (2) 15-prism diopter (Δ) or more exodeviation at distance or near by prism and alternate cover test (PACT) but at least 10 Δ exodeviation at distance by PACT. Participants were assigned randomly to either observation (no treatment for 6 months) or patching prescribed for 3 hours daily for 5 months, followed by 1 month of no patching. The primary outcome was deterioration, defined as constant exotropia measuring at least 10 Δ at distance and near or receipt of nonprotocol treatment for IXT. Of the 177 participants (88%) completing the 6-month primary outcome examination, deterioration occurred in 4.6% (4 of 87) of the participants in the observation group and in 2.2% (2 of 90) of the participants in the patching group (difference, 2.4%; P = 0.27; 95% confidence interval, -3.8% to +9.4%). Motor deterioration occurred in 2.3% (2 of 87) of the observation group and in 2.2% (2 of 90) of the patching group (difference, 0.08%; P = 0.55; 95% confidence interval, -5.8% to +6.1%). For the observation and patching groups, respectively, 6-month mean PACT measurements were 27.9 Δ versus 24.9 Δ at distance (P = 0.02) and 19.3 Δ versus 17.0 Δ at near (P = 0.10); 6-month mean exotropia control scores were 2.8 versus 2.3 points at distance (P = 0.02) and 1.4 versus 1.1 points at near (P = 0.26). Among children 12 to 35 months of age with previously untreated IXT, deterioration over 6 months was uncommon, with or without patching treatment. There was insufficient evidence to recommend part-time patching for the treatment of IXT in children in this age group. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier

  2. Comparative life cycle assessments: The case of paper and digital media

    Energy Technology Data Exchange (ETDEWEB)

    Bull, Justin G., E-mail: jgbull@gmail.com; Kozak, Robert A., E-mail: rob.kozak@ubc.ca

    2014-02-15

    The consumption of the written word is changing, as media transitions from paper products to digital alternatives. We reviewed the life cycle assessment (LCA) research literature that compared the environmental footprint of digital and paper media. To validate the role of context in influencing LCA results, we assessed LCAs that did not compare paper and print, but focused on a product or component that is part of the Information and Communication Technology (ICT) sector. Using a framework that identifies problems in LCA conduct, we assessed whether the comparative LCAs were accurate expressions of the environmental footprints of paper and print. We hypothesized that the differences between the product systems that produce paper and digital media weaken LCA's ability to compare environmental footprints. We also hypothesized that the characteristics of ICT as an industrial sector weaken LCA as an environmental assessment methodology. We found that existing comparative LCAs offered problematic comparisons of paper and digital media for two reasons — the stark material differences between ICT products and paper products, and the unique characteristics of the ICT sector. We suggested that the context of the ICT sector, best captured by the concept of “Moore's Law”, will continuously impede the ability of the LCA methodology to measure ICT products. -- Highlights: • We review the LCA research that compares paper and digital media. • We contrast the comparative LCAs with LCAs that examine only digital products. • Stark differences between paper and digital media weakens LCA findings. • Digital products in general challenge the LCA method's reliability. • Continuous innovation and global nature of digital products impedes LCA methodology.

  3. Comparative life cycle assessments: The case of paper and digital media

    International Nuclear Information System (INIS)

    Bull, Justin G.; Kozak, Robert A.

    2014-01-01

    The consumption of the written word is changing, as media transitions from paper products to digital alternatives. We reviewed the life cycle assessment (LCA) research literature that compared the environmental footprint of digital and paper media. To validate the role of context in influencing LCA results, we assessed LCAs that did not compare paper and print, but focused on a product or component that is part of the Information and Communication Technology (ICT) sector. Using a framework that identifies problems in LCA conduct, we assessed whether the comparative LCAs were accurate expressions of the environmental footprints of paper and print. We hypothesized that the differences between the product systems that produce paper and digital media weaken LCA's ability to compare environmental footprints. We also hypothesized that the characteristics of ICT as an industrial sector weaken LCA as an environmental assessment methodology. We found that existing comparative LCAs offered problematic comparisons of paper and digital media for two reasons — the stark material differences between ICT products and paper products, and the unique characteristics of the ICT sector. We suggested that the context of the ICT sector, best captured by the concept of “Moore's Law”, will continuously impede the ability of the LCA methodology to measure ICT products. -- Highlights: • We review the LCA research that compares paper and digital media. • We contrast the comparative LCAs with LCAs that examine only digital products. • Stark differences between paper and digital media weakens LCA findings. • Digital products in general challenge the LCA method's reliability. • Continuous innovation and global nature of digital products impedes LCA methodology

  4. Comparative life cycle assessment and life cycle costing of four disposal scenarios for used polyethylene terephthalate bottles in Mauritius.

    Science.gov (United States)

    Foolmaun, Rajendra Kumar; Ramjeeawon, Toolseeram

    2012-09-01

    The annual rise in population growth coupled with the flourishing tourism industry in Mauritius has lead to a considerable increase in the amount of solid waste generated. In parallel, the disposal of non-biodegradable wastes, especially plastic packaging and plastic bottles, has also shown a steady rise. Improper disposal of used polyethylene terephthalate (PET) bottles constitutes an eyesore to the environmental landscape and is a threat to the flourishing tourism industry. It is of utmost importance, therefore, to determine a suitable disposal method for used PET bottles which is not only environmentally efficient but is also cost effective. This study investigated the environmental impacts and the cost effectiveness of four selected disposal alternatives for used PET bottles in Mauritius. The four disposal routes investigated were: 100% landfilling; 75% incineration with energy recovery and 25% landfilling; 40% flake production (partial recycling) and 60% landfilling; and 75% flake production and 25% landfilling. Environmental impacts of the disposal alternatives were determined using ISO standardized life cycle assessment (LCA) and with the support of SimaPro 7.1 software. Cost effectiveness was determined using life cycle costing (LCC). Collected data were entered into a constructed Excel-based model to calculate the different cost categories, Net present values, damage costs and payback periods. LCA and LCC results indicated that 75% flake production and 25% landfilling was the most environmentally efficient and cost-effective disposal route for used PET bottles in Mauritius.

  5. Comparative evaluation of three alternative power cycles for waste heat recovery from the exhaust of adiabatic diesel engines

    Science.gov (United States)

    Bailey, M. M.

    1985-01-01

    Three alternative power cycles were compared in application as an exhaust-gas heat-recovery system for use with advanced adiabatic diesel engines. The power cycle alternatives considered were steam Rankine, organic Rankine with RC-1 as the working fluid, and variations of an air Brayton cycle. The comparison was made in terms of fuel economy and economic payback potential for heavy-duty trucks operating in line-haul service. The results indicate that, in terms of engine rated specific fuel consumption, a diesel/alternative-power-cycle engine offers a significant improvement over the turbocompound diesel used as the baseline for comparison. The maximum imporvement resulted from the use of a Rankine cycle heat-recovery system in series with turbocompounding. The air Brayton cycle alternatives studied, which included both simple-cycle and compression-intercooled configurations, were less effective and provided about half the fuel consumption improvement of the Rankine cycle alternatives under the same conditions. Capital and maintenance cost estimates were also developed for each of the heat-recovery power cycle systems. These costs were integrated with the fuel savings to identify the time required for net annual savings to pay back the initial capital investment. The sensitivity of capital payback time to arbitrary increases in fuel price, not accompanied by corresponding hardware cost inflation, was also examined. The results indicate that a fuel price increase is required for the alternative power cycles to pay back capital within an acceptable time period.

  6. Life Cycle Assessment of Bio-diesel Production—A Comparative Analysis

    Science.gov (United States)

    Chatterjee, R.; Sharma, V.; Mukherjee, S.; Kumar, S.

    2014-04-01

    This work deals with the comparative analysis of environmental impacts of bio-diesel produced from Jatropha curcas, Rapeseed and Palm oil by applying the life cycle assessment and eco-efficiency concepts. The environmental impact indicators considered in the present paper include global warming potential (GWP, CO2 equivalent), acidification potential (AP, SO2 equivalent) and eutrophication potential (EP, NO3 equivalent). Different weighting techniques have been used to present and evaluate the environmental characteristics of bio-diesel. With the assistance of normalization values, the eco-efficiency was demonstrated in this work. The results indicate that the energy consumption of bio-diesel production is lowest in Jatropha while AP and EP are more in case of Jatropha than that of Rapeseed and Palm oil.

  7. A comparative view of the relationship between the business cycle and mortality, 1871-1900.

    Science.gov (United States)

    Chernomas, R

    1984-01-01

    This article compares two views on the relationship between the business cycle and mortality for the years 1871-1900. First, the views of Robert Higgs, a prominent mainstream economic historian, of the working and living conditions of this period are examined so that we may trace the reasons for his dependence on immigrants and the germs they bring with them as explanations for the procyclical relationship between mortality and short-term economic growth. This explanation is then criticized by re-examining the working and living conditions of this period and by linking these conditions to a disease theory that does not depend on exogenous forces to explain mortality patterns but rather one that focuses on historically specific political and economic processes and decisions.

  8. Comparative life cycle assessment of wastewater treatment in Denmark including sensitivity and uncertainty analysis

    DEFF Research Database (Denmark)

    Niero, Monia; Pizzol, Massimo; Gundorph Bruun, Henrik

    2014-01-01

    Wastewater treatment has nowadays multiple functions and produces both clean effluents and sludge, which is increasingly seen as a resource rather than a waste product. Technological as well as management choices influence the performance of wastewater treatment plants (WWTPs) on the multiple...... functions. In this context, Life Cycle Assessment (LCA) can determine what choices provide the best environmental performance. However, the assessment is not straightforward due to the intrinsic space and time-related variability of the wastewater treatment process. These challenges were addressed...... in a comparative LCA of four types of WWTPs, representative of mainstream treatment options in Denmark. The four plant types differ regarding size and treatment technology: aerobic versus anaerobic, chemical vs. combined chemical and biological. Trade-offs in their environmental performance were identified...

  9. Life cycle assessment to compare the environmental impact of seven contemporary food waste management systems.

    Science.gov (United States)

    Edwards, Joel; Othman, Maazuza; Crossin, Enda; Burn, Stewart

    2018-01-01

    Municipal food waste (FW) represents 35-45% of household residual waste in Australia, with the nation generating 1.6Tg annually. It is estimated that 91% of this FW ends up in landfill. This study used life cycle assessment to determine and compare the environmental impact of seven contemporary FW management systems for two real-life jurisdictions; incorporating the complete waste service and expanding the system to include inert and garden waste. Although, no system exhibited a best ranking across all impact categories, FW digestion based systems were all revealed to have a lower global warming potential than composting and landfilling systems. Mechanical biological treatment, anaerobic co-digestion, and home composting all demonstrated the lowest environmental impacts for two or more of the environmental impact categories assessed. The assessment included market and technological specific variables and uncertainties providing a framework for robust decision making at a municipality level. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  10. Comparative life cycle assessment of biowaste to resource management systems - A Danish case study

    DEFF Research Database (Denmark)

    Thomsen, Marianne; Seghetta, Michele; Mikkelsen, Mette Hjorth

    2017-01-01

    Waste to Energy combustion plants currently process most of the organic fraction of the household waste. This study presents an assessment of the environmental performance of an increased circular bioresource management system obtained by reallocating the organic fraction of the household waste...... from combustion (Reference Scenario) to biogas and fertilizer production (Alternative Scenario). The goals defined in the Danish National resource action plan for waste management, i.e. 33% reduction of organic fraction household waste dry weight, is taken as a case study. A comparative life cycle...... assessment of the diverting of the organic fraction of the household waste away from a Waste to Energy combustion plant towards sludge- and manure-based biogas plants in North Zealand (Denmark) shows a net increase in renewable electricity production of 39% at the expense of a reduction in heat production...

  11. Intermittent versus Continuous Physiotherapy in Children with Cerebral Palsy

    Science.gov (United States)

    Christiansen, Annette Sandahl; Lange, Christa

    2008-01-01

    The aim of this study was to compare the effect of the delivery of the same amount of intermittent versus continuous physiotherapy given to children with cerebral palsy (CP). This was organized either in an intermittent regime four times a week for 4 weeks alternating with a 6-week treatment pause, or a continuous once or twice a week regime, both…

  12. Intermittency in {sup 197}Au fragmentation

    Energy Technology Data Exchange (ETDEWEB)

    Dabrowska, A; Holynski, R; Olszewski, A; Szarska, M; Wilczynska, B; Wolter, W; Wosiek, B [Institute of Nuclear Physics, Cracow (Poland); Cherry, M L; Deines-Jones, P; Jones, W V; Sengupta, K; Wefel, B [Louisiana State Univ., Baton Rouge, LA (United States). Dept. of Physics and Astronomy; Waddington, C J [Minnesota Univ., Minneapolis, MN (United States). School of Physics and Astronomy; Pozharova, E A; Skorodko, T Yu [Inst. of Theoretical and Experimental Physics, Moscow (Russian Federation); KLMM Collaboration

    1995-07-01

    The concept of factorial moments was applied to an analysis of the dynamical fluctuations in the charge distributions of the fragments emitted from gold nuclei with energies 10.6 and < 1.0 GeV/n interacting with emulsion nuclei. Clear evidence for intermittent fluctuations has been found in an analysis using all the particles released from the gold projectile, with a stronger effect observed below 1 GeV/n than at 10.6 GeV/n. For the full data sets, however, the intermittency effect was found to be very sensitive to the singly charged particles, and neglecting these particles strongly reduces the intermittency signal. When the analysis is restricted to the multiply charged fragments, an intermittency effect is revealed only for multifragmentation events, although one that is enhanced as compared to the analysis of all, singly and multiply charged, particles. The properties of the anomalous fractal dimensions suggest a sequential decay mechanism, rather than the existence of possible critical behaviour in the process of nuclear fragmentation. The likely influence of the charge conservation effects and the finite size of decaying systems on the observed intermittency signals was pointed out. (author). 37 refs, 9 figs, 5 tabs.

  13. Comparative performance analysis of low-temperature Organic Rankine Cycle (ORC) using pure and zeotropic working fluids

    International Nuclear Information System (INIS)

    Aghahosseini, S.; Dincer, I.

    2013-01-01

    In this paper, a comprehensive thermodynamic analysis of the low-grade heat source Organic Rankine Cycle (ORC) is conducted and the cycle performance is analyzed and compared for different pure and zeotropic-mixture working fluids. The comparative performance evaluation of the cycle using a combined energy and exergy analysis is carried out by sensitivity assessment of the cycle certain operating parameters such as efficiency, flow rate, irreversibility, and heat input requirement at various temperatures and pressures. The environmental characteristics of the working fluids such as toxicity, flammability, ODP and GWP are studied and the cycle CO 2 emission is compared with different fuel combustion systems. R123, R245fa, R600a, R134a, R407c, and R404a are considered as the potential working fluids. Results from this analysis provide valuable insight into selection of the most suitable working fluids for power generating application at different operating conditions with a minimal environmental impact. -- Highlights: ► Combined energy and exergy analysis is conducted for Organic Rankine Cycle. ► Comparative assessment is performed for different pure and zeotropic working fluids. ► Exergy and energy efficiency, cycle irreversibility, and required external heat are analyzed. ► Toxicity, flammability, ODP and GWP of considered working fluids are studied. ► Environmental benefits of the renewable/waste heat-based ORC are investigated

  14. A Phase I study of intermittently dosed vorinostat in combination with bortezomib in patients with advanced solid tumors.

    Science.gov (United States)

    Deming, Dustin A; Ninan, Jacob; Bailey, Howard H; Kolesar, Jill M; Eickhoff, Jens; Reid, Joel M; Ames, Matthew M; McGovern, Renee M; Alberti, Dona; Marnocha, Rebecca; Espinoza-Delgado, Igor; Wright, John; Wilding, George; Schelman, William R

    2014-04-01

    Accumulating evidence shows evidence of efficacy with the combination of vorinostat and bortezomib in solid tumors. We previously examined a once-daily continuous dosing schedule of vorinostat in combination with bortezomib which was well tolerated in cycles 1 and 2; however, there was concern regarding the tolerability through multiple cycles. This study was conducted to evaluate an intermittent dosing schedule of vorinostat with bortezomib. Vorinostat was initially administered orally twice daily on days 1-14 with bortezomib IV on days 1, 4, 8, and 11 of a 21 day cycle. Two DLTs (elevated ALT and fatigue) were observed at dose level 1, thus the protocol was amended to administer vorinostat intermittently twice daily on days 1-4 and 8-11. 29 patients were enrolled; 13 men and 16 women. Common cancer types included sarcoma, pancreatic, colorectal, GIST, and breast. The most common Grade 3-4 toxicities at any dose level included thrombocytopenia, fatigue, increased ALT, elevated INR, and diarrhea. DLTs in the intermittent dosing scheduled included thrombocytopenia and fatigue. The Cmax and AUC for the intermittent dosing regimen were similar to those observed in the daily dosing. In this heavily pretreated population, stable disease was observed in patients with sarcoma, colorectal adenocarcinoma and GIST. The MTD was established at vorinostat 300 mg BID on days 1-4 and 8-11 and bortezomib 1.3 mg/m(2) IV on days 1, 4, 8, and 11 of a 21 day cycle. Tolerability was not improved with the intermittent dosing schedule of vorinostat when compared to continuous dosing.

  15. High rates of organic carbon processing in the hyporheic zone of intermittent streams.

    Science.gov (United States)

    Burrows, Ryan M; Rutlidge, Helen; Bond, Nick R; Eberhard, Stefan M; Auhl, Alexandra; Andersen, Martin S; Valdez, Dominic G; Kennard, Mark J

    2017-10-16

    Organic carbon cycling is a fundamental process that underpins energy transfer through the biosphere. However, little is known about the rates of particulate organic carbon processing in the hyporheic zone of intermittent streams, which is often the only wetted environment remaining when surface flows cease. We used leaf litter and cotton decomposition assays, as well as rates of microbial respiration, to quantify rates of organic carbon processing in surface and hyporheic environments of intermittent and perennial streams under a range of substrate saturation conditions. Leaf litter processing was 48% greater, and cotton processing 124% greater, in the hyporheic zone compared to surface environments when calculated over multiple substrate saturation conditions. Processing was also greater in more saturated surface environments (i.e. pools). Further, rates of microbial respiration on incubated substrates in the hyporheic zone were similar to, or greater than, rates in surface environments. Our results highlight that intermittent streams are important locations for particulate organic carbon processing and that the hyporheic zone sustains this fundamental process even without surface flow. Not accounting for carbon processing in the hyporheic zone of intermittent streams may lead to an underestimation of its local ecological significance and collective contribution to landscape carbon processes.

  16. Quasistatic Dynamics with Intermittency

    International Nuclear Information System (INIS)

    Leppänen, Juho; Stenlund, Mikko

    2016-01-01

    We study an intermittent quasistatic dynamical system composed of nonuniformly hyperbolic Pomeau–Manneville maps with time-dependent parameters. We prove an ergodic theorem which shows almost sure convergence of time averages in a certain parameter range, and identify the unique physical family of measures. The theorem also shows convergence in probability in a larger parameter range. In the process, we establish other results that will be useful for further analysis of the statistical properties of the model.

  17. Quasistatic Dynamics with Intermittency

    Energy Technology Data Exchange (ETDEWEB)

    Leppänen, Juho; Stenlund, Mikko, E-mail: mikko.stenlund@helsinki.fi [University of Helsinki, Department of Mathematics and Statistics (Finland)

    2016-06-15

    We study an intermittent quasistatic dynamical system composed of nonuniformly hyperbolic Pomeau–Manneville maps with time-dependent parameters. We prove an ergodic theorem which shows almost sure convergence of time averages in a certain parameter range, and identify the unique physical family of measures. The theorem also shows convergence in probability in a larger parameter range. In the process, we establish other results that will be useful for further analysis of the statistical properties of the model.

  18. Comparative life cycle analysis of cement made with coal vs hazardous waste as fuel

    International Nuclear Information System (INIS)

    Kelly, K.E.; Beeh, J.

    1994-01-01

    The purpose of this life cycle analysis (LCA) is to compare the life cycle of cement made with coal, the standard fuel used in a cement kiln, versus cement made with hazardous waste-derived fuels. The intent of the study is to determine whether the use of hazardous waste as a fuel in the production of cement could result in an increase in detrimental effects to either health or environment. Those evaluated for potential adverse effect include cement kiln workers, waste transporters, and consumers using the final product for private use. The LCA stages included all the processes involved with cement, including raw materials acquisition, transportation, manufacturing, packaging, distribution, use, recycling, and disposal. The overall conclusions of the LCA are that use of waste fuels instead of coal to make cement: (1) does not increase, and may reduce, the concentration of contaminants in the cement product due to the reduction or elimination of the use of coal; (2) reduces or eliminates use of non-renewable fossil fuels, such as coal, as well as the environmental damage and impacts associated with coal mining; (3) provides a more environmentally beneficial means of destroying many types of wastes than alternative treatment methods, including incineration, thus decreasing the need for waste treatment facilities and capacity; (4) decreases overall emissions during transportation but may increase the overall consequences of accidents or spills; (5) results in cement product which may be packaged, transported, distributed and used in the same manner as cement product made with coal; (6) lowers the cost of cement production; and (7) overall appears to result in less health and environmental impacts

  19. Comparing cycling world hour records, 1967-1996: modeling with empirical data.

    Science.gov (United States)

    Bassett, D R; Kyle, C R; Passfield, L; Broker, J P; Burke, E R

    1999-11-01

    The world hour record in cycling has increased dramatically in recent years. The present study was designed to compare the performances of former/current record holders, after adjusting for differences in aerodynamic equipment and altitude. Additionally, we sought to determine the ideal elevation for future hour record attempts. The first step was constructing a mathematical model to predict power requirements of track cycling. The model was based on empirical data from wind-tunnel tests, the relationship of body size to frontal surface area, and field power measurements using a crank dynamometer (SRM). The model agreed reasonably well with actual measurements of power output on elite cyclists. Subsequently, the effects of altitude on maximal aerobic power were estimated from published research studies of elite athletes. This information was combined with the power requirement equation to predict what each cyclist's power output would have been at sea level. This allowed us to estimate the distance that each rider could have covered using state-of-the-art equipment at sea level. According to these calculations, when racing under equivalent conditions, Rominger would be first, Boardman second, Merckx third, and Indurain fourth. In addition, about 60% of the increase in hour record distances since Bracke's record (1967) have come from advances in technology and 40% from physiological improvements. To break the current world hour record, field measurements and the model indicate that a cyclist would have to deliver over 440 W for 1 h at sea level, or correspondingly less at altitude. The optimal elevation for future hour record attempts is predicted to be about 2500 m for acclimatized riders and 2000 m for unacclimatized riders.

  20. Chaos synchronization based on intermittent state observer

    Institute of Scientific and Technical Information of China (English)

    Li Guo-Hui; Zhou Shi-Ping; Xu De-Ming

    2004-01-01

    This paper describes the method of synchronizing slave to the master trajectory using an intermittent state observer by constructing a synchronizer which drives the response system globally tracing the driving system asymptotically. It has been shown from the theory of synchronization error-analysis that a satisfactory result of chaos synchronization is expected under an appropriate intermittent period and state observer. Compared with continuous control method,the proposed intermittent method can target the desired orbit more efficiently. The application of the method is demonstrated on the hyperchaotic Rossler systems. Numerical simulations show that the length of the synchronization interval rs is of crucial importance for our scheme, and the method is robust with respect to parameter mismatch.

  1. Comparative Evaluation of Biomass Power Generation Systems in China Using Hybrid Life Cycle Inventory Analysis

    Science.gov (United States)

    Liu, Huacai; Yin, Xiuli; Wu, Chuangzhi

    2014-01-01

    There has been a rapid growth in using agricultural residues as an energy source to generate electricity in China. Biomass power generation (BPG) systems may vary significantly in technology, scale, and feedstock and consequently in their performances. A comparative evaluation of five typical BPG systems has been conducted in this study through a hybrid life cycle inventory (LCI) approach. Results show that requirements of fossil energy savings, and greenhouse gas (GHG) emission reductions, as well as emission reductions of SO2 and NOx, can be best met by the BPG systems. The cofiring systems were found to behave better than the biomass-only fired system and the biomass gasification systems in terms of energy savings and GHG emission reductions. Comparing with results of conventional process-base LCI, an important aspect to note is the significant contribution of infrastructure, equipment, and maintenance of the plant, which require the input of various types of materials, fuels, services, and the consequent GHG emissions. The results demonstrate characteristics and differences of BPG systems and help identify critical opportunities for biomass power development in China. PMID:25383383

  2. Comparative Evaluation of Biomass Power Generation Systems in China Using Hybrid Life Cycle Inventory Analysis

    Directory of Open Access Journals (Sweden)

    Huacai Liu

    2014-01-01

    Full Text Available There has been a rapid growth in using agricultural residues as an energy source to generate electricity in China. Biomass power generation (BPG systems may vary significantly in technology, scale, and feedstock and consequently in their performances. A comparative evaluation of five typical BPG systems has been conducted in this study through a hybrid life cycle inventory (LCI approach. Results show that requirements of fossil energy savings, and greenhouse gas (GHG emission reductions, as well as emission reductions of SO2 and NOx, can be best met by the BPG systems. The cofiring systems were found to behave better than the biomass-only fired system and the biomass gasification systems in terms of energy savings and GHG emission reductions. Comparing with results of conventional process-base LCI, an important aspect to note is the significant contribution of infrastructure, equipment, and maintenance of the plant, which require the input of various types of materials, fuels, services, and the consequent GHG emissions. The results demonstrate characteristics and differences of BPG systems and help identify critical opportunities for biomass power development in China.

  3. Comparing Terrestrial Organic Carbon Cycle Dynamics in Interglacial and Glacial Climates in the South American Tropics

    Science.gov (United States)

    Fornace, K. L.; Galy, V.; Hughen, K. A.

    2014-12-01

    The application of compound-specific radiocarbon dating to molecular biomarkers has allowed for tracking of specific organic carbon pools as they move through the environment, providing insight into complex processes within the global carbon cycle. Here we use this technique to investigate links between glacial-interglacial climate change and terrestrial organic carbon cycling in the catchments of Cariaco Basin and Lake Titicaca, two tropical South American sites with well-characterized climate histories since the last glacial period. By comparing radiocarbon ages of terrestrial biomarkers (leaf wax compounds) with deposition ages in late glacial and Holocene sediments, we are able to gauge the storage time of these compounds in the catchments in soils, floodplains, etc. before transport to marine or lacustrine sediments. We are also able to probe the effects of temperature and hydrologic change individually by taking advantage of opposite hydrologic trends at the two sites: while both were colder during the last glacial period, precipitation at Titicaca decreased from the last glacial period to the Holocene, but the late glacial was marked by drier conditions at Cariaco. Preliminary data from both sites show a wide range of apparent ages of long-chain n-fatty acids (within error of 0 to >10,000 years older than sediment), with the majority showing ages on the order of several millennia at time of deposition and age generally increasing with chain length. While late glacial leaf waxes appear to be older relative to sediment than those deposited in the Holocene at both sites, at Cariaco we find a ~2-3 times larger glacial-interglacial age difference than at Titicaca. We hypothesize that at Titicaca the competing influences of wetter and colder conditions during the last glacial period, which respectively tend to increase and decrease the rate of organic carbon turnover on land, served to minimize the contrast between glacial and interglacial leaf wax storage time

  4. High temperature abatement of acid gases from waste incineration. Part II: Comparative life cycle assessment study.

    Science.gov (United States)

    Biganzoli, Laura; Racanella, Gaia; Marras, Roberto; Rigamonti, Lucia

    2015-01-01

    The performances of a new dolomitic sorbent, named Depurcal®MG, to be directly injected at high temperature in the combustion chamber of Waste-To-Energy (WTE) plants as a preliminary stage of deacidification, were experimentally tested during full-scale commercial operation. Results of the experimentations were promising, and have been extensively described in Biganzoli et al. (2014). This paper reports the Life Cycle Assessment (LCA) study performed to compare the traditional operation of the plants, based on the sole sodium bicarbonate feeding at low temperature, with the new one, where the dolomitic sorbent is injected at high temperature. In the latter the sodium bicarbonate is still used, but at lower rate because of the decreased load of acid gases entering the flue gas treatment line. The major goal of the LCA was to make sure that a burden shifting was not taking place somewhere in the life cycle stages, as it might be the case when a new material is used in substitution of another one. According to the comparative approach, only the processes which differ between the two operational modes were included in the system boundaries. They are the production of the two reactants and the treatment of the corresponding solid residues arising from the neutralisation of acid gases. The additional CO2 emission at the stack of the WTE plant due to the activation of the sodium bicarbonate was also included in the calculation. Data used in the modelling of the foreground system are primary, derived from the experimental tests described in Biganzoli et al. (2014) and from the dolomitic sorbent production plant. The results of the LCA show minor changes in the potential impacts between the two operational modes of the plants. These differences are for 8 impact categories in favour of the new operational mode based on the addition of the dolomitic sorbent, and for 7 impact categories in favour of the traditional operation. A final evaluation was conducted on the potential

  5. Investigation into life-cycle costing as a comparative analysis approach of energy systems

    CSIR Research Space (South Africa)

    Mokheseng, B

    2010-08-31

    Full Text Available selection based on a simple payback period. Due to life-cycle stages, often the real costs of the project or equipment, either to the decision maker or the cost bearer, are not reflected by the upfront capital costs. In this paper, the life-cycle costing...

  6. Intermittent aerosol delivery to the lungs during high-flow nasal cannula therapy.

    Science.gov (United States)

    Golshahi, Laleh; Longest, P Worth; Azimi, Mandana; Syed, Aamer; Hindle, Michael

    2014-10-01

    Use of submicrometer particles combined with condensational growth techniques has been proposed to reduce drug losses within components of high-flow nasal cannula therapy systems and to enhance the dose reaching the lower respiratory tract. These methods have been evaluated using continuous inhalation flow rather than realistic inhalation/exhalation breathing cycles. The goal of this study was to evaluate in vitro aerosol drug delivery using condensational growth techniques during high-flow nasal cannula therapy using realistic breathing profiles and incorporating intermittent aerosol delivery techniques. A mixer-heater combined with a vibrating mesh nebulizer was used to generate a submicrometer aerosol using a formulation of 0.2% albuterol sulfate and 0.2% sodium chloride in water. Delivery efficiency of the aerosol for 1 min through a nasal cannula was considered using an intermittent delivery regime with aerosol being emitted for either the entire inhalation time (2 s) or half of the inhalation period (1 s) and compared with continuous delivery. The deposition of the aerosol was evaluated in the nasal delivery components (ventilator tubing and cannula) and an in vitro adult nose-mouth-throat (NMT) model using 3 realistic breathing profiles. Significant improvements in dose delivered to the exit of the NMT model (ex-NMT) were observed for both condensational growth methods using intermittent aerosol delivery compared with continuous delivery, and increasing the tidal volume was found useful. The combination of the largest tidal volume with the shortest intermittent delivery time resulted in the lowest respiration losses and the highest ex-NMT delivered dose. Intermittent aerosol delivery using realistic breathing profiles of submicrometer condensational growth aerosols was found to be efficient in delivering nasally administered drugs in an in vitro airway model. Copyright © 2014 by Daedalus Enterprises.

  7. Replacing single frozen-thawed euploid embryos in a natural cycle in ovulatory women may increase live birth rates compared to medicated cycles in anovulatory women.

    Science.gov (United States)

    Melnick, Alexis P; Setton, Robert; Stone, Logan D; Pereira, Nigel; Xu, Kangpu; Rosenwaks, Zev; Spandorfer, Steven D

    2017-10-01

    The goal of this study was to compare pregnancy outcomes between natural frozen embryo transfer (FET) cycles in ovulatory women and programmed FET cycles in anovulatory women after undergoing in vitro fertilization with preimplantation genetic screening (IVF-PGS). This was a retrospective cohort study performed at an academic medical center. Patients undergoing single FET IVF-PGS cycles between October 2011 and December 2014 were included. Patients were stratified by type of endometrial replacement: programmed cycles with estrogen/progesterone replacement and natural cycles. IVF-PGS with 24-chromosome screening was performed on all included patients. Those patients with euploid embryos had single embryo transfer in a subsequent FET. The primary study outcome was live birth/ongoing pregnancy rate. Secondary outcomes included implantation, biochemical pregnancy, and miscarriage rates. One hundred thirteen cycles met inclusion criteria: 65 natural cycles and 48 programmed cycles. The programmed FET group was younger (35.9 ± 4.5 vs. 37.5 ± 3.7, P = 0.03) and had a higher AMH (3.95 ± 4.2 vs. 2.37 ± 2.4, P = 0.045). The groups were similar for BMI, gravidity, parity, history of uterine surgery, and incidence of Asherman's syndrome. There was also no difference in embryo grade at biopsy or transfer, and proportion of day 5 and day 6 transfers. Implantation rates were higher in the natural FET group (0.66 ± 0.48 vs. 0.44 ± 0.50, P = 0.02). There was no difference in the rates of biochemical pregnancy or miscarriage. After controlling for age, live birth/ongoing pregnancy rate was higher in natural FETs with an adjusted odds ratio of 2.68 (95% CI 1.22-5.87). Natural FET in ovulatory women after IVF-PGS is associated with increased implantation and live birth rates compared to programmed FET in anovulatory women. Further investigation is needed to determine whether these findings hold true in other patient cohorts.

  8. Comparing Life-Cycle Costs of ESPCs and Appropriations-Funded Energy Projects: An Update to the 2002 Report

    International Nuclear Information System (INIS)

    Shonder, John A.; Hughes, Patrick; Atkin, Erica

    2006-01-01

    A study was sponsored by FEMP in 2001 - 2002 to develop methods to compare life-cycle costs of federal energy conservation projects carried out through energy savings performance contracts (ESPCs) and projects that are directly funded by appropriations. The study described in this report follows up on the original work, taking advantage of new pricing data on equipment and on $500 million worth of Super ESPC projects awarded since the end of FY 2001. The methods developed to compare life-cycle costs of ESPCs and directly funded energy projects are based on the following tasks: (1) Verify the parity of equipment prices in ESPC vs. directly funded projects; (2) Develop a representative energy conservation project; (3) Determine representative cycle times for both ESPCs and appropriations-funded projects; (4) Model the representative energy project implemented through an ESPC and through appropriations funding; and (5) Calculate the life-cycle costs for each project.

  9. Life Cycle Assessment of Biofertilizer Production and Use Compared with Conventional Liquid Digestate Management.

    Science.gov (United States)

    Styles, David; Adams, Paul; Thelin, Gunnar; Vaneeckhaute, Céline; Chadwick, David; Withers, Paul J A

    2018-06-12

    Handling of digestate produced by anaerobic digestion impacts the environment through emission of greenhouse gases, reactive nitrogen, and phosphorus. Previous life cycle assessments (LCA) evaluating the extraction of nutrients from digestate using struvite precipitation and ammonia stripping did not relate synthetic fertilizer substitution (SFS) to nutrient use efficiency consequences. We applied an expanded LCA to compare the conventional management of 1 m 3 of liquid digestate (LD) from food waste against the production and use of digestate biofertilizer (DBF) extracted from LD, accounting for SFS efficacy. Avoidance of CH 4 , N 2 O, and NH 3 emissions from LD handling and enhanced SFS via more targeted use of nutrients in the versatile DBF product could generate environmental savings of up to 0.129 kg Sb eq, 4.16 kg SO 2 eq, 1.22 kg PO 4 eq, 33 kg CO 2 eq, and 20.6 MJ eq per m 3 LD, for abiotic resource depletion, acidification, eutrophication, global warming, and cumulative energy demand burdens, respectively. However, under worst-case assumptions, DBF extraction could increase global warming and cumulative energy demand by 7.5 kg CO 2 e and 251 MJ eq per m 3 LD owing to processing inputs. Normalizing these results against per capita environmental loadings, we conclude that DBF extraction is environmentally beneficial.

  10. A qualitative comparative survey of First Cycle radiography programmes in Europe and Japan

    International Nuclear Information System (INIS)

    Akimoto, Tatsuhito; Caruana, Carmel J.; Shimosegawa, Masayuki

    2009-01-01

    Purpose: To qualitatively compare First Cycle Radiography programmes in Europe and Japan. Methods: This qualitative survey was conducted via a series of case-studies of university-based radiography curricula in Europe and Japan. Findings and conclusions: The main themes arising from the survey were that: (a) in Europe the freedom that most universities have in setting their own curricula and examinations means that in practice there is still a wide variability in curricula between and within states. On the other hand in Japan curricula are more uniform owing to central government guidelines regarding radiography education and a centrally administered national radiography examination. This means that student and worker mobility is much easier for Japanese radiographers. (b) in some countries in Europe principles of reporting and healthcare management are being expanded at the expense of the more technological aspects of radiography. Physical science competences on the other hand are considered highly in Japanese culture and form a major part of the curriculum. This may indicate that Japanese students would be in a much better position to cope with role developments linked to changes in imaging technology. Pragmatically oriented studies need to be carried out to determine ways in which radiographers can enhance their role without sacrificing their technological competences. The profession cannot afford to lose its technological expertise - it is neither in the interest of the profession itself and even less of the patient.

  11. Life Cycle Assessment Comparing the Use of Jatropha Biodiesel in the Indian Road and Rail Sectors

    Energy Technology Data Exchange (ETDEWEB)

    Whitaker, M.; Heath, G.

    2010-05-01

    This life cycle assessment of Jatropha biodiesel production and use evaluates the net greenhouse gas (GHG) emission (not considering land-use change), net energy value (NEV), and net petroleum consumption impacts of substituting Jatropha biodiesel for conventional petroleum diesel in India. Several blends of biodiesel with petroleum diesel are evaluated for the rail freight, rail passenger, road freight, and road-passenger transport sectors that currently rely heavily on petroleum diesel. For the base case, Jatropha cultivation, processing, and use conditions that were analyzed, the use of B20 results in a net reduction in GHG emissions and petroleum consumption of 14% and 17%, respectively, and a NEV increase of 58% compared with the use of 100% petroleum diesel. While the road-passenger transport sector provides the greatest sustainability benefits per 1000 gross tonne kilometers, the road freight sector eventually provides the greatest absolute benefits owing to substantially higher projected utilization by year 2020. Nevertheless, introduction of biodiesel to the rail sector might present the fewest logistic and capital expenditure challenges in the near term. Sensitivity analyses confirmed that the sustainability benefits are maintained under multiple plausible cultivation, processing, and distribution scenarios. However, the sustainability of any individual Jatropha plantation will depend on site-specific conditions.

  12. Application of a life cycle assessment to compare environmental performance in coal mine tailings management.

    Science.gov (United States)

    Adiansyah, Joni Safaat; Haque, Nawshad; Rosano, Michele; Biswas, Wahidul

    2017-09-01

    This study compares coal mine tailings management strategies using life cycle assessment (LCA) and land-use area metrics methods. Hybrid methods (the Australian indicator set and the ReCiPe method) were used to assess the environmental impacts of tailings management strategies. Several strategies were considered: belt filter press (OPT 1), tailings paste (OPT 2), thickened tailings (OPT 3), and variations of OPT 1 using combinations of technology improvement and renewable energy sources (OPT 1A-D). Electrical energy was found to contribute more than 90% of the environmental impacts. The magnitude of land-use impacts associated with OPT 3 (thickened tailings) were 2.3 and 1.55 times higher than OPT 1 (tailings cake) and OPT 2 (tailings paste) respectively, while OPT 1B (tailings belt filter press with technology improvement and solar energy) and 1D (tailings belt press filter with technology improvement and wind energy) had the lowest ratio of environmental impact to land-use. Further analysis of an economic cost model and reuse opportunities is required to aid decision making on sustainable tailings management and industrial symbiosis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Human health tradeoffs in wellhead drinking water treatment: Comparing exposure reduction to embedded life cycle risks.

    Science.gov (United States)

    Gifford, Mac; Chester, Mikhail; Hristovski, Kiril; Westerhoff, Paul

    2018-01-01

    Treatment of drinking water decreases human health risks by reducing pollutants, but the required materials, chemicals, and energy emit pollutants and increase health risks. We explored human carcinogenic and non-carcinogenic disease tradeoffs of water treatment by comparing pollutant dose-response curves against life cycle burden using USEtox methodology. An illustrative wellhead sorbent groundwater treatment system removing hexavalent chromium or pentavalent arsenic serving 3200 people was studied. Reducing pollutant concentrations in drinking water from 20 μg L -1 to 10 μg L -1 avoided 37 potential cancer cases and 64 potential non-cancer disease cases. Human carcinogenicity embedded in treatment was 0.2-5.3 cases, and non-carcinogenic toxicity was 0.2-14.3 cases, depending on technology and degree of treatment. Embedded toxicity impacts from treating Cr(VI) using strong-base anion exchange were 90% of the toxicity impacts for treatment options requiring pH control. In scenarios where benefits exceeded burdens, tradeoffs still existed. Benefits are experienced by a local population but burdens are born externally where the materials and energy are produced, thus exporting the health risks. Even when burdens clearly exceeded benefits, cost considerations may still drive selecting a detrimental treatment level or technology. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Comparing the effects of rise time and inspiratory cycling criteria on 6 different mechanical ventilators.

    Science.gov (United States)

    Gonzales, Joshua F; Russian, Christopher J; Gregg Marshall, S; Collins, Kevin P

    2013-03-01

    Inspiratory rise time and cycling criteria are important settings in pressure support ventilation. The purpose of this study was to investigate the impact of minimum and maximum rise time and inspiratory cycling criteria settings on 6 new generation ventilators. Our hypothesis was there would be a difference in the exhaled tidal volume, inspiratory time, and peak flow among 6 different ventilators, based, on change in rise time and cycling criteria. The research utilized a breathing simulator and 4 different ventilator models. All mechanical ventilators were set to a spontaneous mode of ventilation with settings of pressure support 8 cm H2O and PEEP of 5 cm H2O. A minimum and maximum setting for rise time and cycling criteria were examined. Exhaled tidal volume, inspiratory time, and peak flow measurements were recorded for each simulation. Significant (P ventilator. Significant differences in exhaled tidal volume, inspiratory time, and peak flow were observed by adjusting rise time and cycling criteria. This research demonstrates that during pressure support ventilation strategy, adjustments in rise time and/or cycling criteria can produce changes in inspiratory parameters. Obviously, this finding has important implications for practitioners who utilize a similar pressure support strategy when conducting a ventilator wean. Additionally, this study outlines major differences among ventilator manufacturers when considering inspiratory rise time and cycling criteria.

  15. High temperature abatement of acid gases from waste incineration. Part II: Comparative life cycle assessment study

    Energy Technology Data Exchange (ETDEWEB)

    Biganzoli, Laura, E-mail: laura.biganzoli@mail.polimi.it [Politecnico di Milano, Department of Civil and Environmental Engineering, Piazza L. da Vinci 32, 20133 Milano (Italy); Racanella, Gaia [Politecnico di Milano, Department of Civil and Environmental Engineering, Piazza L. da Vinci 32, 20133 Milano (Italy); Marras, Roberto [Unicalce S.p.A., R and D Department, Via Tonio da Belledo 30, 23900 Lecco (Italy); Rigamonti, Lucia [Politecnico di Milano, Department of Civil and Environmental Engineering, Piazza L. da Vinci 32, 20133 Milano (Italy)

    2015-01-15

    Highlights: • Two scenarios of acid gases removal in WTE plants were compared in an LCA study. • A detailed inventory based on primary data has been reported for the production of the new dolomitic sorbent. • Results show that the comparison between the two scenarios does not show systematic differences. • The potential impacts are reduced only if there is an increase in the energy efficiency of the WTE plant. - Abstract: The performances of a new dolomitic sorbent, named Depurcal®MG, to be directly injected at high temperature in the combustion chamber of Waste-To-Energy (WTE) plants as a preliminary stage of deacidification, were experimentally tested during full-scale commercial operation. Results of the experimentations were promising, and have been extensively described in Biganzoli et al. (2014). This paper reports the Life Cycle Assessment (LCA) study performed to compare the traditional operation of the plants, based on the sole sodium bicarbonate feeding at low temperature, with the new one, where the dolomitic sorbent is injected at high temperature. In the latter the sodium bicarbonate is still used, but at lower rate because of the decreased load of acid gases entering the flue gas treatment line. The major goal of the LCA was to make sure that a burden shifting was not taking place somewhere in the life cycle stages, as it might be the case when a new material is used in substitution of another one. According to the comparative approach, only the processes which differ between the two operational modes were included in the system boundaries. They are the production of the two reactants and the treatment of the corresponding solid residues arising from the neutralisation of acid gases. The additional CO{sub 2} emission at the stack of the WTE plant due to the activation of the sodium bicarbonate was also included in the calculation. Data used in the modelling of the foreground system are primary, derived from the experimental tests described in

  16. Thermo-economic analysis of recuperated Maisotsenko bottoming cycle using triplex air saturator: Comparative analyses

    International Nuclear Information System (INIS)

    Saghafifar, Mohammad; Omar, Amr; Erfanmoghaddam, Sepehr; Gadalla, Mohamed

    2017-01-01

    Highlights: • Proposing recuperated Maisotsenko bottoming cycle (RMBC) as a new combined cycle. • Introducing triplex air saturator for waste heat recovery application. • Conducting thermodynamic optimization to maximize RMBC thermal efficiency. • Conducting thermo-economic optimization to minimize RMBC cost of electricity. - Abstract: A recently recommended combined cycle power plant is to employ another gas turbine cycle for waste heat recovery as an air bottoming cycle (ABC). There are some studies conducted to improve ABC’s thermodynamic performance utilizing commonly power augmentation methods such as steam/water injection. In particular, it is proposed to employ Maisotsenko gas turbine cycle as a bottoming cycle, i.e. Maisotsenko bottoming cycle (MBC). Due to the promising performance of the MBC configuration, it is decided to investigate a recuperated MBC (RMBC) configuration by recommending the triplex air saturator. In this way, the air saturator consists of three sections. The first section is an indirect evaporative cooler while the other two sections are responsible for heat recovery from the topping and bottoming cycle turbines exhaust. In this paper, thermodynamic and thermo-economic analyses are carried out to study the main merits and demerits of RMBC against MBC configuration. Thermodynamic optimization results indicate that the maximum achievable efficiency for MBC and RMBC incorporation in a simple gas turbine power plant are 39.40% and 44.73%, respectively. Finally, thermo-economic optimization shows that the optimum levelized cost of electricity for MBC and RMBC power plants are 62.922 US$/MWh and 58.154 US$/MWh, respectively.

  17. Intermittency in Complex Flows

    Science.gov (United States)

    Ben Mahjoub, Otman; Redondo, Jose M.

    2017-04-01

    Experimental results of the complex turbulent wake of a cilinder in 2D [1] and 3D flows [2] were used to investigate the scaling of structure functions, similar research was also performed on wave propagation and breaking in the Ocean [3], in the the stratified Atmosphere (ABL) [4] and in a 100large flume (UPC) for both regular and irregular waves, where long time series of waves propagating and generating breaking turbulence velocity rms and higher order measurements were taken in depth. [3,5] by means of a velocimeter SONTEK3-D. The probability distribution functions of the velocity differences and their non Gaussian distribution related to the energy spectrum indicate that irregularity is an important source of turbulence. From Kolmogorov's K41 and K61 intermittency correction: the p th-order longitudinal velocity structure function δul at scale l in the inertial range of three-dimensional fully developed turbulence is related by ⟨δup⟩ = ⟨(u(x+ l)- u(x))p⟩ ˜ ɛp0/3lp/3 l where ⟨...⟩ represents the spatial average over flow domain, with ɛ0 the mean energy dissipation per unit mass and l is the separation distance. The importance of the random nature of the energy dissipation led to the K62 theory of intermittency, but locality and non-homogeneity are key issues. p p/3 p/3 ξd ⟨δul⟩ ˜ ⟨ɛl ⟩l ˜ l and ξp = p 3 + τp/3 , where now ɛl is a fractal energy dissipation at scale l, τp/3 is the scaling of and ξp is the scaling exponent of the velocity structure function of order p. Both in K41 and K62, the structure functions of third order related to skewness is ξ3 = 1. But this is not true either. We show that scaling exponents ξp do deviate from early studies that only investigated homogeneous turbulence, where a large inertial range dominates. The use of multi-fractal analysis and improvements on Structure function calculations on standard Enhanced mixing is an essential property of turbulence and efforts to alter and to control

  18. Intermittency in nuclear multifragmentation

    International Nuclear Information System (INIS)

    Ploszajczak, M.; Tucholski, A.

    1990-07-01

    Fluctuations of the fragment size distribution in a percolation model and in nuclear multifragmentation following the breakup of high energy nuclei in the nuclear emulsion are studied using the method of scaled factorial moments. An intermittent patern of fluctuations is found in the data as well as in the percolation lattice calculation. This is a consequence of both a self-similarity in the fragment size distribution and a random character for the scaling law. These fluctuations are in general well-described by percolation model. The multifractal dimensions are calculated and their relevance to the study of possible critical behaviour is pointed out. (orig.)

  19. Multidimensional intermittency in hadronic collisions

    International Nuclear Information System (INIS)

    Pan, J.; Hwa, R.C.

    1992-06-01

    The study of intermittency in high-energy hadronic collisions by the Monte Carlo code ECCO is extended to 3-dimensional phase space. Strong intermittency is found in agreement with the data. Fluctuation in the impact parameter is responsible for the intermittency in lnp T , and the transverse-momentum conservation leads to negative intermittency slopes in the azimuthal angle φ. The Ochs-Wosiek plots are linear in all dimensions having universal slopes. An exponent ν = 1.448 emerges to characterize multiparticle production in pp collisions. The properties of G moments are also examined, and the fractal dimensions determined

  20. [Objective evaluation of arterial intermittent claudication by the walking tolerance test. Comparative study of physiological walking and walking on a conveyor belt (author's transl)].

    Science.gov (United States)

    Bouchet, J Y; Franco, A; Morzol, B; Beani, J C

    1980-01-01

    Two methods are used to evaluate the walking distance: physiological walking along a standard path (0% - 6 mk/h) and walking on a tread mill (10% - 3 km/h). In both tests, four data are checked: -- initial trouble distance, -- cramp or walking-distance, -- localisation of pain, -- recovery time. These tests are dependable for the diagnosis of arterial claudication, reproducible and well tolerated. Their results have been compared: there is no correlation between the initial trouble distance and the cramp distance. However there is a correlation between the cramp distance by physiological walking and on treadmill. Recovery time, if long, is a criteria of gravity. Interests of both methods are discussed.

  1. Comparative life cycle assessment of alternative strategies for energy recovery from used cooking oil.

    Science.gov (United States)

    Lombardi, Lidia; Mendecka, Barbara; Carnevale, Ennio

    2018-06-15

    The separate collection of Used Cooking Oil (UCO) is gaining popularity through several countries in Europe. An appropriate management of UCO waste stream leads to substantial benefits. In this study, we analyse two different possibilities of UCO energy reuse: the direct feed to a reciprocating internal combustion engine (ICE) for cogeneration purpose, and the processing to generate biodiesel. Concerning biodiesel production, we analyse four among conventional and innovative technologies, characterised by different type and amount of used chemicals, heat and electricity consumptions and yields. We perform a systematic evaluation of environmental benefits and drawbacks by applying life cycle assessment (LCA) analysis to compare the alternatives. For the impact assessment, two methods are selected: the Global Warming Potential (GWP) and Cumulative Exergy Consumption (CExC). Results related only to the processing phases (i.e. not including yet the avoided effects) show that the recovery of UCO in cogeneration plant has in general lower values in terms of environmental impacts than its employment in biodiesel production. When products and co-products substitution are included, the savings obtained by the substitution of conventional diesel production, in the biodiesel cases, are significantly higher than the avoided effects for electricity and heat in the cogeneration case. In particular, by using the UCO in the biodiesel production processes, the savings vary from 41.6 to 54.6 GJ ex per tUCO, and from 2270 to 2860 kg CO 2eq per tUCO for CExC and GWP, respectively. A particular focus is put on sensitivity and uncertainty analyses. Overall, high uncertainty of final results for process impacts is observed, especially for the supercritical methanol process. Low uncertainty values are evaluated for the avoided effects. Including the uncertain character of the impacts, cogeneration scenario and NaOH catalysed process of biodiesel production result to be the most suitable

  2. Complex economic dynamics: Chaotic saddle, crisis and intermittency

    International Nuclear Information System (INIS)

    Chian, Abraham C.-L.; Rempel, Erico L.; Rogers, Colin

    2006-01-01

    Complex economic dynamics is studied by a forced oscillator model of business cycles. The technique of numerical modeling is applied to characterize the fundamental properties of complex economic systems which exhibit multiscale and multistability behaviors, as well as coexistence of order and chaos. In particular, we focus on the dynamics and structure of unstable periodic orbits and chaotic saddles within a periodic window of the bifurcation diagram, at the onset of a saddle-node bifurcation and of an attractor merging crisis, and in the chaotic regions associated with type-I intermittency and crisis-induced intermittency, in non-linear economic cycles. Inside a periodic window, chaotic saddles are responsible for the transient motion preceding convergence to a periodic or a chaotic attractor. The links between chaotic saddles, crisis and intermittency in complex economic dynamics are discussed. We show that a chaotic attractor is composed of chaotic saddles and unstable periodic orbits located in the gap regions of chaotic saddles. Non-linear modeling of economic chaotic saddle, crisis and intermittency can improve our understanding of the dynamics of financial intermittency observed in stock market and foreign exchange market. Characterization of the complex dynamics of economic systems is a powerful tool for pattern recognition and forecasting of business and financial cycles, as well as for optimization of management strategy and decision technology

  3. Efeito de oito semanas de suplementação com creatina monoidratada sobre o trabalho total relativo em esforços intermitentes máximos no cicloergômetro de homens treinados Effect of eight weeks of creatine supplementation on relative total work in intermittent maximal efforts in the cycle ergometer of trained men

    Directory of Open Access Journals (Sweden)

    Leandro Ricardo Altimari

    2006-06-01

    Full Text Available Este estudo investigou o efeito de um longo período de suplementação com creatina monoidratada (Cr m sobre o trabalho total relativo (TTR em esforços intermitentes máximos no cicloergômetro de homens treinados. Vinte seis indivíduos foram divididos aleatoriamente em grupo creatina (CR, n=13 e grupo placebo (PL, n=13. Os sujeitos receberam em sistema duplo-cego, doses de Cr m ou placebo-maltodextrina (20 g.d-1 por 5 dias e 3 g.d-1 durante 51 dias subseqüentes. Os grupos tiveram seus hábitos alimentares e sua condição física previamente controlados. Para determinação do TTR os sujeitos foram submetidos a protocolo de exercício em cicloergômetro composto de três Testes de Wingate de 30s separados por dois minutos recuperação, antes e após o período de suplementação. ANOVA, seguido pelo teste post hoc de Tukey, quando pThis study investigated the effect of long-term supplementation with creatine monohydrate (Cr m on relative total work (RTW in intermittent maximal efforts in the cycle ergometer of trained men. Twenty six individuals were randomly divided in creatine group (CR, n=13 and placebo group (PL, n=13. The subjects received in a double-blind manner, doses of Cr m or placebo-maltodextrin (20 g.d-1 for 5 days and 3 g.d-1 for 51 subsequent days. The groups had their alimentary habits and physical fitness controlled previously. For determination of the RTW the subjects were submitted to exercise protocol in cycle ergometer comprised three 30s Anaerobic Wingate Test interspersed with two minutes recovery, before and after the supplementation period. ANOVA, followed by the Tukey post hoc test, when p<0.05, were used for data treatment. There was a significant time effect for RTW (F1,24=8.00; p<0.05, with the CR group demonstrating significant greater (3% on the RTW production compared to PL group after the supplementation period (690.54 ± 46.83 vs 655.71 ± 74.34 J.kg-1 respectively; p<0.05. The results of the present study

  4. Comparative study of oestrous cycles and ovulation characteristics of cattle kept at different altitudes in Peru

    International Nuclear Information System (INIS)

    Cardenas, H.; Vivanco, W.; Alvarado, E.; Padilla, A.; Flores, A.

    1990-01-01

    Progesterone (P 4 ) profiles were used to characterize certain aspects of the oestrous cycle in dairy Holstein (H) heifers bred under a typical intensive management system in the central coast area of Peru (12 deg. 05' S, 76 deg. 57' W) and in Brown Swiss (BS) and Simmental (SIM) dual purpose heifers reared under extensive management conditions in the central highlands (14 deg. 07' S, 70 deg. 43' W, 4250 m elevation). In the coastal experiment a group of eight H heifers were evaluated during their normal oestrous cycles, and a similar group after synchronization with norgestomet and oestradiol valerate. Serum concentrations of P 4 were measured throughout the oestrous cycles by RIA in daily samples obtained from the jugular vein. The occurrence of ovulation at 30 h after the onset of standing oestrus was determined by laparoscopy or by rectal palpation. Oestrus detection was performed by visual observation of anatomical changes and homosexual behaviour. In the trial carried out in the highlands, eight naturally cycling BS and seven SIM, as well as eight PGF 2α synchronized BS and four SIM, were studied. Parameters similar to those mentioned for the coastal experiment were evaluated in this trial. The evaluations of the PGF 2α synchronized heifers were performed from the commencement of treatment to the end of the first oestrous cycle. The profiles of serum P 4 during natural oestrous cycles of H heifers on the coast and BS and SIM in the highlands were similar to those already defined for cattle in other environments. The PGF 2α treated BS and SIM heifers showed more rapid luteolysis than control heifers; as a consequence, the overall P 4 profiles in synchronized and natural oestruses were different. However, ovulations occurred about 30 h after the onset of standing oestrus in both naturally cycling and synchronized heifers in both environments. (author). 37 refs, 7 figs, 3 tabs

  5. A Comparative Cycle and Refrigerant Simulation Procedure Applied on Air-Water Heat Pumps

    DEFF Research Database (Denmark)

    Mader, Gunda; Palm, Björn; Elmegaard, Brian

    2012-01-01

    A vapor compression heat pump absorbs heat from the environment at a low temperature level and rejects heat at a high temperature level. The bigger the difference between the two temperature levels the more challenging is it to gain high energy efficiency with a basic cycle layout as found in most...... small capacity heat pump applications today. Many of the applicable refrigerants also reach their technical limits regarding low vapor pressure for very low source temperatures and high discharge temperatures for high sink temperatures. These issues are especially manifest for air-water heat pumps. Many...... alternative cycle setups and refrigerants are known to improve the energy efficiency of a vapor compression cycle and reduce discharge temperatures. However not all of them are feasible for small capacity heat pumps from a cost and complexity point of view. This paper presents a novel numerical approach...

  6. Metabolic Effects of Intermittent Fasting.

    Science.gov (United States)

    Patterson, Ruth E; Sears, Dorothy D

    2017-08-21

    The objective of this review is to provide an overview of intermittent fasting regimens, summarize the evidence on the health benefits of intermittent fasting, and discuss physiological mechanisms by which intermittent fasting might lead to improved health outcomes. A MEDLINE search was performed using PubMed and the terms "intermittent fasting," "fasting," "time-restricted feeding," and "food timing." Modified fasting regimens appear to promote weight loss and may improve metabolic health. Several lines of evidence also support the hypothesis that eating patterns that reduce or eliminate nighttime eating and prolong nightly fasting intervals may result in sustained improvements in human health. Intermittent fasting regimens are hypothesized to influence metabolic regulation via effects on (a) circadian biology, (b) the gut microbiome, and (c) modifiable lifestyle behaviors, such as sleep. If proven to be efficacious, these eating regimens offer promising nonpharmacological approaches to improving health at the population level, with multiple public health benefits.

  7. Water vapor measurements at ALOMAR over a solar cycle compared with model calculations by LIMA

    Science.gov (United States)

    Hartogh, P.; Sonnemann, G. R.; Grygalashvyly, M.; Song, Li; Berger, U.; Lübken, F.-J.

    2010-01-01

    Microwave water vapor measurements between 40 and 80 km altitude over a solar cycle (1996-2006) were carried out in high latitudes at Arctic Lidar Observatory for Middle Atmosphere Research (ALOMAR) (69.29°N, 16.03°E), Norway. Some smaller gaps and three interruptions of monitoring in the winters 1996/1997 and 2005/2006 and from spring 2001 to spring 2002 occurred during this period. The observations show a distinct year-to-year variability not directly related to solar Lyman-α radiation. In winter the water vapor mixing ratios in the upper domain were anticorrelated to the solar activity, whereas in summer, minima occurred in the years after the solar maximum in 2000/2001. In winter, sudden stratospheric warmings (SSWs) modulated the water vapor mixing ratios. Within the stratopause region a middle atmospheric water vapor maximum was observed, which results from the methane oxidation and is a regular feature there. The altitude of the maximum increased by approximately 5 km as summer approached. The largest mixing ratios were monitored in autumn. During the summer season a secondary water vapor maximum also occurred above 65 km most pronounced in late summer. The solar Lyman-α radiation impacts the water vapor mixing ratio particularly in winter above 65 km. In summer the correlation is positive below 70 km. The correlation is also positive in the lower mesosphere/stratopause region in winter due to the action of sudden stratospheric warmings, which occur more frequently under the condition of high solar activity and the enhancing the humidity. A strong day-to-day variability connected with planetary wave activity was found throughout the entire year. Model calculations by means of Leibniz-Institute Middle Atmosphere model (LIMA) reflect the essential patterns of the water vapor variation, but the results also show differences from the observations, indicating that exchange processes between the troposphere and stratosphere not modeled by LIMA could have

  8. Comparative life cycle cost assessment of painted and hot-dip galvanized bridges.

    Science.gov (United States)

    Rossi, B; Marquart, S; Rossi, G

    2017-07-15

    The study addresses the life cycle cost assessment (LCCA) of steel bridges, focusing on the maintenance activities and the maintenance scenario. Firstly, the unit costs of maintenance activities and their durability (i.e. the time between two activities) are evaluated. Pragmatic data are provided for the environment category C4 and for three activities: Patch Up, Overcoating and Remove & Replace. A comparative LCCA for a typical hypothetic steel girder bridge is carried out, either painted or hot-dip galvanized (HDG), in the environmental class C4. The LCC versus the cumulated life is provided for both options. The initial cost of the steel unpainted option is only 50.3% of the HDG option. It is shown that after 'Overcoating' occurring at 18.5 years, the total Net Present Value (NPV) of the painted option surpasses that of the HDG option. A sensitivity analysis of the NPV to the cost and service life parameters, the escalation and discount rates is then performed. The discount and escalation rates, considerably influences the total LCC, following a non-linear trend. The total LCC decreases with the discount rate increasing and, conversely, increases with the escalation rate increasing. Secondly, the influence of the maintenance scenario on the total LCC is assessed based on a probabilistic approach. A permutation of the three independent maintenance activities assumed to occur six times over the life of the bridge is considered and a probability of occurrence is associated to each unique scenario. The most probable scenarios are then classified according to their NPV or achieved service life. This approach leads to the definition of a cost-effective maintenance scenario i.e. the scenario, within all the considered permutations, that has the minimum LCC in a range of lifespan. Besides, the probabilistic analysis also shows that, whatever the scenario, the return on investment period ranges between 18.5 years and 24.2 years. After that period, the HDG option becomes

  9. A comparative thermodynamic analysis of ORC and Kalina cycles for waste heat recovery: A case study for CGAM cogeneration system

    Directory of Open Access Journals (Sweden)

    Arash Nemati

    2017-03-01

    Full Text Available A thermodynamic modeling and optimization is carried out to compare the advantages and disadvantages of organic Rankine cycle (ORC and Kalina cycle (KC as a bottoming cycle for waste heat recovery from CGAM cogeneration system. Thermodynamic models for combined CGAM/ORC and CGAM/KC systems are performed and the effects of some decision variables on the energy and exergy efficiency and turbine size parameter of the combined systems are investigated. Solving simulation equations and optimization process have been done using direct search method by EES software. It is observed that at the optimum pressure ratio of air compressor, produced power of bottoming cycles has minimum values. Also, evaporator pressure optimizes the performance of cycle, but this optimum pressure level in ORC (11 bar is much lower than that of Kalina (46 bar. In addition, ORC's simpler configuration, higher net produced power and superheated turbine outlet flow, which leads to a reliable performance for turbine, are other advantages of ORC. Kalina turbine size parameter is lower than that of the ORC which is a positive aspect of Kalina cycle. However, by a comprehensive comparison between Kalina and ORC, it is concluded that the ORC has significant privileges for waste heat recovery in this case.

  10. Fate in intermittent claudication

    DEFF Research Database (Denmark)

    Jelnes, Rolf; Gaardsting, O; Hougaard Jensen, K

    1986-01-01

    , or an ankle/arm pressure index below 50% were individually significantly associated with progression of the arteriosclerotic disease. These findings show the importance of peripheral blood pressure measurements in the management of patients with intermittent claudication due to arteriosclerotic disease........ The rate of clinical progression of the arteriosclerotic disease (that is, rest pain or gangrene) of the worst affected leg was 7.5% in the first year after referral. Thereafter the rate was 2.2% a year. An ankle systolic blood pressure below 70 mm Hg, a toe systolic blood pressure below 40 mm Hg...... 113 of the patients (44%) had died. Causes of death were no different from those in the general population. Mortality was twice that of the general population matched for age and sex. Mortality among the men was twice that among the women. In men under 60 mortality was four times that expected...

  11. Postexercise cold-water immersion improves intermittent high-intensity exercise performance in normothermia.

    Science.gov (United States)

    McCarthy, Avina; Mulligan, James; Egaña, Mikel

    2016-11-01

    A brief cold water immersion between 2 continuous high-intensity exercise bouts improves the performance of the latter compared with passive recovery in the heat. We investigated if this effect is apparent in normothermic conditions (∼19 °C), employing an intermittent high-intensity exercise designed to reflect the work performed at the high-intensity domain in team sports. Fifteen young active men completed 2 exhaustive cycling protocols (Ex1 and Ex2: 12 min at 85% ventilatory threshold (VT) and then an intermittent exercise alternating 30-s at 40% peak power (P peak ) and 30 s at 90% P peak to exhaustion) separated by 15 min of (i) passive rest, (ii) 5-min cold-water immersion at 8 °C, and (iii) 10-min cold-water immersion at 8 °C. Core temperature, heart rate, rates of perceived exertion, and oxygen uptake kinetics were not different during Ex1 among conditions. Time to failure during the intermittent exercise was significantly (P immersions (7.2 ± 3.5 min and 7.3 ± 3.3 min, respectively) compared with passive rest (5.8 ± 3.1 min). Core temperature, heart rate, and rates of perceived exertion were significantly (P immersions compared with passive rest. The time constant of phase II oxygen uptake response during the 85% VT bout of Ex2 was not different among the 3 conditions. A postexercise, 5- to 10-min cold-water immersion increases subsequent intermittent high-intensity exercise compared with passive rest in normothermia due, at least in part, to reductions in core temperature, circulatory strain, and effort perception.

  12. Measuring and Comparing Descend in Elite Race Cycling with a Perspective on Real-Time Feedback for Improving Individual Performance

    NARCIS (Netherlands)

    Reijne, M.M.; Bregman, D.J.J.; Schwab, A.L.; Espinosa, Hugo G.; Rowlands, David R.; Shepherd, Jonathan; Thiel, David V.

    2018-01-01

    Descend technique and performance vary among elite racing cyclists and it is not clear what slower riders should do to improve their performance. An observation study was performed of the descending technique of members of a World Tour cycling team and the technique of each member was compared with

  13. A Comparative Life Cycle Assessment of Hot Mixes Asphalt Containing Bituminous Binder Modified with Waste and Virgin Polymers

    NARCIS (Netherlands)

    Oliveira dos Santos, Joao Miguel; Cerezo, Veronique; Soudani, Khedoudja; Bressi, Sara

    2018-01-01

    This paper presents the results of a life cycle assessment undertaken to compare the potential environmental impacts associated with the use of asphalt surface mixtures produced with polymer modified bitumen with those of a conventional asphalt surface mixture. Seven types of hot mix asphalt

  14. Comparative Life Cycle Studies on Poly(3-hydroxybutyrate)-Based Composites as Potential Replacement for Conventional Petrochemical Plastics

    NARCIS (Netherlands)

    Pietrini, M.; Roes, A.L.; Patel, M.K.; Chiellini, E.

    2007-01-01

    A cradle-to-grave environmental life cycle assessment (LCA) of a few poly(3-hydroxybutyrate) (PHB) based composites has been performed and was compared to commodity petrochemical polymers. The end products studied are a cathode ray tube (CRT) monitor housing (conventionally produced from high-impact

  15. Intermittent pressure decreases human keratinocyte proliferation in vitro.

    Science.gov (United States)

    Nasca, Maria R; Shih, Alan T; West, Dennis P; Martinez, Wanda M; Micali, Giuseppe; Landsman, Adam S

    2007-01-01

    The aim of this study was to investigate the correlation between pressure changes and keratinocyte proliferation by determining whether keratinocytes exposed to altered mechanical pressures would proliferate at different rates compared to control cells not subjected to pressure changes. Tissue culture flasks of human keratinocytes plated at an approximate density of 15,000 cells/cm(2) undergoing an intermittent cyclic pressure of 362 mm Hg at a frequency of 2.28 or 5.16 cycles/min (0.038 or 0.086 Hz) for 8 h were compared to control flasks grown at ambient room pressure. An in-line pressure transducer was used to monitor and adjust pressure within the cell chambers, using a solenoid valve. A thymidine incorporation assay assessed the amount of cell proliferation in each set of experiments. Differences in proliferation between keratinocytes subjected to cyclic pressure changes and control cells were found to be statistically significant (p < 0.05) in 4 out of 5 proliferation assays. Also, a higher frequency of pressure changes consistently generated a reduced proliferation rate compared to that seen in cells exposed to a lower frequency of pressure changes. These data indicate that keratinocytes undergoing intermittent pressure changes exhibit decreased proliferation rates compared to controls. Furthermore, an increased frequency rate seems to have a greater effect on proliferation than low-frequency rate pressure changes, suggesting that the stress caused by frequently changed pressure may play a greater role in reducing keratinocyte proliferation than the actual magnitude of load applied to the cells. Our results support the current treatment protocol of reducing speed and duration of walking on the site of the wound to promote healing of foot ulcers. (c) 2007 S. Karger AG, Basel.

  16. The impact of intermittent or sustained carbon dioxide on intermittent hypoxia initiated respiratory plasticity. What is the effect of these combined stimuli on apnea severity?

    Science.gov (United States)

    Mateika, Jason H; Panza, Gino; Alex, Raichel; El-Chami, Mohamad

    2017-10-31

    The following review explores the effect that intermittent or sustained hypercapnia coupled to intermittent hypoxia has on respiratory plasticity. The review explores published work which suggests that intermittent hypercapnia leads to long-term depression of respiration when administered in isolation and prevents the initiation of long-term facilitation when administered in combination with intermittent hypoxia. The review also explores the impact that sustained hypercapnia alone and in combination with intermittent hypoxia has on the magnitude of long-term facilitation. After exploring the outcomes linked to intermittent hypoxia/hypercapnia and intermittent hypoxia/sustained hypercapnia the translational relevance of the outcomes as it relates to breathing stability during sleep is addressed. The likelihood that naturally induced cycles of intermittent hypoxia, coupled to oscillations in carbon dioxide that range between hypocapnia and hypercapnia, do not initiate long-term facilitation is addressed. Moreover, the conditions under which intermittent hypoxia/sustained hypercapnia could serve to improve breathing stability and mitigate co-morbidities associated with sleep apnea are considered. Published by Elsevier B.V.

  17. Comparative life cycle assessment of disposable and reusable laryngeal mask airways.

    Science.gov (United States)

    Eckelman, Matthew; Mosher, Margo; Gonzalez, Andres; Sherman, Jodi

    2012-05-01

    Growing awareness of the negative impacts from the practice of health care on the environment and public health calls for the routine inclusion of life cycle criteria into the decision-making process of device selection. Here we present a life cycle assessment of 2 laryngeal mask airways (LMAs), a one-time-use disposable Unique™ LMA and a 40-time-use reusable Classic™ LMA. In life cycle assessment, the basis of comparison is called the "functional unit." For this report, the functional unit of the disposable and reusable LMAs was taken to be maintenance of airway patency by 40 disposable LMAs or 40 uses of 1 reusable LMA. This was a cradle-to-grave study that included inputs and outputs for the manufacture, transport, use, and waste phases of the LMAs. The environmental impacts of the 2 LMAs were estimated using SimaPro life cycle assessment software and the Building for Environmental and Economic Sustainability impact assessment method. Sensitivity and simple life cycle cost analyses were conducted to aid in interpretation of the results. The reusable LMA was found to have a more favorable environmental profile than the disposable LMA as used at Yale New Haven Hospital. The most important sources of impacts for the disposable LMA were the production of polymers, packaging, and waste management, whereas for the reusable LMA, washing and sterilization dominated for most impact categories. The differences in environmental impacts between these devices strongly favor reusable devices. These benefits must be weighed against concerns regarding transmission of infection. Health care facilities can decrease their environmental impacts by using reusable LMAs, to a lesser extent by selecting disposable LMA models that are not made of certain plastics, and by ordering in bulk from local distributors. Certain practices would further reduce the environmental impacts of reusable LMAs, such as increasing the number of devices autoclaved in a single cycle to 10 (-25% GHG

  18. Integrated approach for characterizing and comparing exposure-based impacts with life cycle impacts

    DEFF Research Database (Denmark)

    Fantke, Peter; Jolliet, Olivier

    2016-01-01

    ions that involve burden shifting or that result in only incremental improvement. Focusing in the life cycle impacts on widely accepted and applied impact categories like global warming potential or cumulative energy demand aggregating several impact categories will lead to underestimations of life...... to the environment from product-related processes along the product life cycle. We build on a flexible mass balance-based modeling system yielding cumulative multimedia transfer fractions and exposure pathway-specific Product Intake Fractions defined as chemical mass taken in by humans per unit mass of chemical...... in a product. When combined chemical masses in products and further with toxicity information, this approach is a resourceful way to inform CAA and minimize human exposure to toxic chemicals in consumer products through both product use and environmental emissions. We use an example of chemicals in consumer...

  19. Comparative of fuel cycle cost for light water nuclear power plants

    International Nuclear Information System (INIS)

    Kocic, A.; Dimitrijevic, Z.

    1978-01-01

    Starting from ost general fuel cycle scheme for light water reactors this article deals with conceptual differences of BWR, PWR and WWER as well as with the influence of certain phases of fuel cycle on economic parameters of an equivalent 1000 MWe reactor using a computer program CENA /1/ and typical parameters of each reactor type. An analysis of two particular power plants 628 MWe and 440 MWe WWER by means of the same program is given in the second part of this paper taking into account the differences of in-core fuel management. This second approach is especially interesting for the economy of the power plant itself in the period of planning. (author)

  20. Comparative Human Health Impact Assessment of Engineered Nanomaterials in the Framework of Life Cycle Assessment.

    Science.gov (United States)

    Fransman, Wouter; Buist, Harrie; Kuijpers, Eelco; Walser, Tobias; Meyer, David; Zondervan-van den Beuken, Esther; Westerhout, Joost; Klein Entink, Rinke H; Brouwer, Derk H

    2017-07-01

    For safe innovation, knowledge on potential human health impacts is essential. Ideally, these impacts are considered within a larger life-cycle-based context to support sustainable development of new applications and products. A methodological framework that accounts for human health impacts caused by inhalation of engineered nanomaterials (ENMs) in an indoor air environment has been previously developed. The objectives of this study are as follows: (i) evaluate the feasibility of applying the CF framework for NP exposure in the workplace based on currently available data; and (ii) supplement any resulting knowledge gaps with methods and data from the life cycle approach and human risk assessment (LICARA) project to develop a modified case-specific version of the framework that will enable near-term inclusion of NP human health impacts in life cycle assessment (LCA) using a case study involving nanoscale titanium dioxide (nanoTiO 2 ). The intent is to enhance typical LCA with elements of regulatory risk assessment, including its more detailed measure of uncertainty. The proof-of-principle demonstration of the framework highlighted the lack of available data for both the workplace emissions and human health effects of ENMs that is needed to calculate generalizable characterization factors using common human health impact assessment practices in LCA. The alternative approach of using intake fractions derived from workplace air concentration measurements and effect factors based on best-available toxicity data supported the current case-by-case approach for assessing the human health life cycle impacts of ENMs. Ultimately, the proposed framework and calculations demonstrate the potential utility of integrating elements of risk assessment with LCA for ENMs once the data are available. © 2016 Society for Risk Analysis.

  1. Comparative study of pulsed and steady-state tokamak reactor burn cycles

    International Nuclear Information System (INIS)

    Ehst, D.A.; Brooks, J.N.; Cha, Y.; Evans, K.; Hassanein, A.M.; Kim, S.; Majumdar, S.; Misra, B.; Stevens, H.C.

    1984-05-01

    Four distinct operating modes have been proposed for tokamaks. Our study focuses on capital costs and lifetime limitations of reactor subsystems in an attempt to quantify sensitivity to pulsed operation. Major problem areas considered include: thermal fatigue on first wall, limiter/divertor; thermal energy storage; fatigue in pulsed poloidal field coils; out-of-plant fatigue and eddy current heating in toroidal field coils; electric power supply costs; and noninductive driver costs. We assume a high availability and low cost of energy will be mandatory for a commercial fusion reactor, and we characterize improvements in physics and engineering which will help achieve these goals for different burn cycles

  2. Long-term effects of recurrent intermittent hypoxia and hyperoxia on respiratory system mechanics in neonatal mice.

    Science.gov (United States)

    Dylag, Andrew M; Mayer, Catherine A; Raffay, Thomas M; Martin, Richard J; Jafri, Anjum; MacFarlane, Peter M

    2017-04-01

    Premature infants are at increased risk for wheezing disorders. Clinically, these neonates experience recurrent episodes of apnea and desaturation often treated by increasing the fraction of inspired oxygen (FIO 2 ). We developed a novel paradigm of neonatal intermittent hypoxia with subsequent hyperoxia overshoots (CIH O/E ) and hypothesized that CIH O/E elicits long-term changes on pulmonary mechanics in mice. Neonatal C57BL/6 mice received CIH O/E , which consisted of 10% O2 (1 min) followed by a transient exposure to 50% FIO 2 , on 10-min repeating cycles 24 h/d from birth to P7. Baseline respiratory mechanics, methacholine challenge, RT-PCR for pro and antioxidants, radial alveolar counts, and airway smooth muscle actin were assessed at P21 after 2-wk room air recovery. Control groups were mice exposed to normoxia, chronic intermittent hyperoxia (CIH E ), and chronic intermittent hypoxia (CIH O ). CIH O/E and CIH E increased airway resistance at higher doses of methacholine and decreased baseline compliance compared with normoxia mice. Lung mRNA for NOX2 was increased by CIH O/E . Radial alveolar counts and airway smooth muscle actin was not different between groups. Neonatal intermittent hypoxia/hyperoxia exposure results in long-term changes in respiratory mechanics. We speculate that recurrent desaturation with hyperoxia overshoot may increase oxidative stress and contribute to wheezing in former preterm infants.

  3. Intermedia and Intermittency

    Directory of Open Access Journals (Sweden)

    Veres Bálint

    2014-12-01

    Full Text Available It is commonly known that medial reflections have been initiated by attempts to secure the borders of discrete medial forms and to define the modus operandi of each essentialized medial area. Later on, the focus of study has shifted to plurimedial formations and the interactions between predefined medial genres. In the last few decades, taxonomic approaches to various multi-, inter-, and transmedial phenomena dominated the discussions, which offered invaluable support in mapping the terrain, but at the same time hindered the analysis of the ephemeral, time-dependent aspects of plurimedial operations. While we explore the properties of each medial configuration, we lose sight of the actual historical drivers that produce ever-new configurations. My thesis is that any discourse on intermediality should be paralleled by a discourse on cultural intermittency, and consequently, media studies should involve an approach that focuses on the “ecosystem” of the constantly renewing media configurations from the point of view of their vitalizing potential and capability to trigger heightened experiences. This approach draws much inspiration from K. Ludwig Pfeiffer’s media anthropology that gives orientation in my paper.

  4. Post-prandial carbohydrate ingestion during 1-h of moderate-intensity, intermittent cycling does not improve mood, perceived exertion, or subsequent power output in recreationally-active exercisers

    Directory of Open Access Journals (Sweden)

    O’Neal Eric K

    2013-01-01

    Full Text Available Abstract Background This study compared the effects of ingesting water (W, a flavored carbohydrate-electrolyte (CE or a flavored non-caloric electrolyte (NCE beverage on mood, ratings of perceived exertion (RPE, and sprint power during cycling in recreational exercisers. Methods Men (n = 23 and women (n = 13 consumed a 24–h standardized diet and reported 2–4 h post-prandial for all test sessions. After a familiarization session, participants completed 50 min of stationary cycling in a warm environment (wet bulb globe temperature = 25.0°C at ~ 60-65% of heart rate reserve (146 ± 4 bpm interspersed with 5 rest periods of 2 min each. During exercise, participants consumed W, CE, or NCE, served in a counterbalanced cross-over design. Beverage volume was served in 3 aliquots equaling each individual’s sweat losses (mean 847 ± 368 mL during the familiarization session. Profiles of Mood States questionnaires (POMS were administered and blood glucose levels were determined pre- and post- sub-maximal cycling. Following sub-maximal exercise, participants completed 3 30–s Wingate anaerobic tests (WAnT with 2.5 min rest between tests to assess performance. Results Blood glucose was higher (p AnT for CE (6.1 ± 1.7 mmol/L compared to W (4.9 ± 1.5 mmol/L and NCE (4.6 ± 1.2 mmol/L. Nonetheless, there were no differences among treatments in peak (642 ± 153, 635 ± 143, 650 ± 141 watts for W, NCE, and CE, respectively; p  =  0.44 or mean (455 ± 100, 458 ± 95, 454 ± 95 watts for W, NCE, and CE, respectively; p = 0.62 power for the first WAnT or mean (414 ± 92, 425 ± 85, 423 ± 82 watts, respectively; p = 0.13 power output averaged across all 3 WAnT. Likewise, RPE during submaximal exercise, session RPE, and fatigue and vigor assessed by POMS did not differ among beverage treatments (p > 0.05. Conclusions Carbohydrate ingestion consumed by recreational

  5. Chronic Intermittent Hypoxia Induces Atherosclerosis

    OpenAIRE

    Savransky, Vladimir; Nanayakkara, Ashika; Li, Jianguo; Bevans, Shannon; Smith, Philip L.; Rodriguez, Annabelle; Polotsky, Vsevolod Y.

    2007-01-01

    Rationale: Obstructive sleep apnea, a condition leading to chronic intermittent hypoxia (CIH), is associated with hyperlipidemia, atherosclerosis, and a high cardiovascular risk. A causal link between obstructive sleep apnea and atherosclerosis has not been established.

  6. Plutonium purification cycle in centrifugal extractors: comparative study of flowsheets using uranous nitrate and hydroxylamine nitrate

    International Nuclear Information System (INIS)

    Baron, P.; Dinh, B.; Mauborgne, B.; Drain, F.; Gillet, B.

    1998-01-01

    The extension of the UP2 plant at La Hague includes a new plutonium purification cycle using multi-stage centrifugal extractors, to replace the present cycle which uses mixer/settler banks. The advantage of this type of extractor is basically the compactness of the equipment and the short residence time, which limits solvent degradation, particularly when reprocessing fuel containing a high proportion of plutonium 238. Two types of reducing agents have been considered for the plutonium stripping operation, uranous nitrate and hydroxylamine nitrate. Uranous nitrate displays a very fast reduction kinetics, ideal for the very short residence time of the phases in the centrifugal extractors. However, its extractability in the organic phase exacerbates the undesirable re-oxidation of plutonium, which is present in high concentration in this stage of the process. The short residence time of the centrifugal extractors is an advantage in as much as it could conceivably be adequate to obtain a sufficient reduction efficiency, while minimizing undesirable re-oxidation mechanisms. Hydroxylamine nitrate helps to minimize undesirable re-oxidation and is the normal choice for this type of operation. However, the plutonium (IV) reduction kinetics obtained is slower than with uranous nitrate, making it necessary to check whether its use is compatible with the very short residence times of centrifugal extractors.This article discusses the feasibility studies employing these two reducing agents. (author)

  7. Comparative life-cycle cost analysis for low-level mixed waste remediation alternatives

    International Nuclear Information System (INIS)

    Jackson, J.A.; White, T.P.; Kloeber, J.M.; Toland, R.J.; Cain, J.P.; Buitrago, D.Y.

    1995-03-01

    The purpose of this study is two-fold: (1) to develop a generic, life-cycle cost model for evaluating low-level, mixed waste remediation alternatives, and (2) to apply the model specifically, to estimate remediation costs for a site similar to the Fernald Environmental Management Project near Cincinnati, OH. Life-cycle costs for vitrification, cementation, and dry removal process technologies are estimated. Since vitrification is in a conceptual phase, computer simulation is used to help characterize the support infrastructure of a large scale vitrification plant. Cost estimating relationships obtained from the simulation data, previous cost estimates, available process data, engineering judgment, and expert opinion all provide input to an Excel based spreadsheet for generating cash flow streams. Crystal Ball, an Excel add-on, was used for discounting cash flows for net present value analysis. The resulting LCC data was then analyzed using multi-attribute decision analysis techniques with cost and remediation time as criteria. The analytical framework presented allows alternatives to be evaluated in the context of budgetary, social, and political considerations. In general, the longer the remediation takes, the lower the net present value of the process. This is true because of the time value of money and large percentage of the costs attributed to storage or disposal

  8. Dynamic characterizers of spatiotemporal intermittency

    OpenAIRE

    Gupte, Neelima; Jabeen, Zahera

    2006-01-01

    Systems of coupled sine circle maps show regimes of spatiotemporally intermittent behaviour with associated scaling exponents which belong to the DP class, as well as regimes of spatially intermittent behaviour (with associated regular dynamical behaviour) which do not belong to the DP class. Both types of behaviour are seen along the bifurcation boundaries of the synchronized solutions, and contribute distinct signatures to the dynamical characterizers of the system, viz. the distribution of...

  9. A systematic review and meta-analysis comparing cardiopulmonary exercise test values obtained from the arm cycle and the leg cycle respectively in healthy adults

    DEFF Research Database (Denmark)

    Larsen, Rasmus Tolstrup; Christensen, Jan; Tang, Lars Hermann

    2016-01-01

    INTRODUCTION: The cardiopulmonary exercise test (CPET) assesses maximal oxygen uptake (VO2max) and is commonly performed on a leg cycle ergometer (LC). However, some individuals would rather perform the CPET on an arm cycle ergometer (AC). OBJECTIVE: The objectives of this study were to undertake...... in studies on older and less active populations. LEVEL OF EVIDENCE: 3a....... a systematic review and meta-analysis of the difference in VO2max achieved by AC compared to LC in healthy adults and to explore factors that may be predictive of this difference. METHODS: MEDLINE, EMBASE, CINAHL, and PEDro were searched in April 2015. The differences in VO2max (ACLCdiff) were pooled across....../min with a mean ACLCratio of 0.70. The ACLCdiff was lower in studies with higher mean age and lower aerobic capacity. CONCLUSION: There is linear association between the AC and LC values in healthy adults. The AC values were on average 70% of the LC values. The magnitude of this difference appeared to be reduced...

  10. A Systematic Review and Meta-analysis Comparing Cardiopulmonary Exercise Test Values Obtained From the Arm Cycle and the Leg Cycle Respectively in Healthy Adults

    DEFF Research Database (Denmark)

    Larsen, Rasmus Tolstrup; Christensen, Jan; Tang, Lars Hermann

    2016-01-01

    INTRODUCTION: The cardiopulmonary exercise test (CPET) assesses maximal oxygen uptake (VO2max) and is commonly performed on a leg cycle ergometer (LC). However, some individuals would rather perform the CPET on an arm cycle ergometer (AC). OBJECTIVE: The objectives of this study were to undertake...... in studies on older and less active populations. LEVEL OF EVIDENCE: 3a....... a systematic review and meta-analysis of the difference in VO2max achieved by AC compared to LC in healthy adults and to explore factors that may be predictive of this difference. METHODS: MEDLINE, EMBASE, CINAHL, and PEDro were searched in April 2015. The differences in VO2max (ACLCdiff) were pooled across....../min with a mean ACLCratio of 0.70. The ACLCdiff was lower in studies with higher mean age and lower aerobic capacity. CONCLUSION: There is linear association between the AC and LC values in healthy adults. The AC values were on average 70% of the LC values. The magnitude of this difference appeared to be reduced...

  11. Measuring and Comparing Descend in Elite Race Cycling with a Perspective on Real-Time Feedback for Improving Individual Performance

    OpenAIRE

    Reijne, M.M.; Bregman, D.J.J.; Schwab, A.L.; Espinosa, Hugo G.; Rowlands, David R.; Shepherd, Jonathan; Thiel, David V.

    2018-01-01

    Descend technique and performance vary among elite racing cyclists and it is not clear what slower riders should do to improve their performance. An observation study was performed of the descending technique of members of a World Tour cycling team and the technique of each member was compared with the fastest descender amongst them. The obtained data gives us guidelines for rider specific feedback in order to improve his performance. The bicycles were equipped with a system that could measur...

  12. Comparative life cycle assessment and financial analysis of mixed culture polyhydroxyalkanoate production.

    Science.gov (United States)

    Gurieff, Nicholas; Lant, Paul

    2007-12-01

    A life cycle assessment and financial analysis of mixed culture PHA (PHA(MC)) and biogas production was undertaken based on treating an industrial wastewater. Internal rate of return (IRR) and non-renewable CO(2)eq emissions were used to quantify financial viability and environmental impact. PHA(MC) was preferable to biogas production for treating the specified industrial effluent. PHA(MC) was also financially attractive in comparison to pure culture PHA production. Both PHA production processes had similar environmental impacts that were significantly lower than HDPE production. A large potential for optimisation exists for the PHA(MC) process as financial and environmental costs were primarily due to energy use for downstream processing. Under the conditions used in this work PHA(MC) was shown to be a viable biopolymer production process and an effective industrial wastewater treatment technology. This is the first study of its kind and provides valuable insight into the PHA(MC) process.

  13. Data supporting the comparative life cycle assessment of different municipal solid waste management scenarios

    Science.gov (United States)

    Ali Rajaeifar, Mohammad; Tabatabaei, Meisam; Ghanavati, Hossein

    2015-01-01

    Environmental assessment of municipal solid waste (MSW) management scenarios would help to select eco-friendly scenarios. In this study, the inventory data in support of life cycle assessment of different MSW are presented. The scenarios were defined as: anaerobic digestion (AD, Sc-0), landfilling combined with composting (Sc-1), incineration (Sc-2), incineration combined with composting (Sc-3), and AD combined with incineration (Sc-4). The current article contains flowcharts of the different scenarios. Additionally, six supplementary files including inventory data on the different scenarios, data on the different damage assessment categories, normalization, and single scores are presented (Supplementary files 1–6). The analysis of the different scenarios revealed that the most eco-friendly scenario to be implemented in the future would be the combination of AD and incineration (Sc-4). PMID:26217743

  14. Data supporting the comparative life cycle assessment of different municipal solid waste management scenarios

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Rajaeifar

    2015-06-01

    Full Text Available Environmental assessment of municipal solid waste (MSW management scenarios would help to select eco-friendly scenarios. In this study, the inventory data in support of life cycle assessment of different MSW are presented. The scenarios were defined as: anaerobic digestion (AD, Sc-0, landfilling combined with composting (Sc-1, incineration (Sc-2, incineration combined with composting (Sc-3, and AD combined with incineration (Sc-4. The current article contains flowcharts of the different scenarios. Additionally, six supplementary files including inventory data on the different scenarios, data on the different damage assessment categories, normalization, and single scores are presented (Supplementary files 1–6. The analysis of the different scenarios revealed that the most eco-friendly scenario to be implemented in the future would be the combination of AD and incineration (Sc-4.

  15. Comparative study of ads and Fr in advanced nuclear fuel cycles

    International Nuclear Information System (INIS)

    Wydler, P.; Van Den Durpel, L.

    2001-01-01

    To respond to questions raised by different governments concerning the role and viability of partitioning and transmutation (P and T) in general and the ADS-option in particular, the OECD/NEA decided in 1998 to launch a systems study. The aim was to clarify and assess: the goals for transmutation, the requirements for a completely closed fuel cycle in which all actinides are ultimately fissioned, and the advantages and drawbacks of the ADS as an actinide burner in comparison with the better known fast reactor. To perform this assessment and evaluate the implications from a technological, waste management and economic cost/benefit perspective, an expert group, composed of 38 experts from 15 countries and three international organisations, was set up and asked to report its conclusions by mid-2001. The paper will overview the work and conclusions of the expert group. (author)

  16. Obstructive sleep apnea and cancer: effects of intermittent hypoxia?

    Science.gov (United States)

    Kukwa, Wojciech; Migacz, Ewa; Druc, Karolina; Grzesiuk, Elzbieta; Czarnecka, Anna M

    2015-01-01

    Obstructive sleep apnea (OSA) is a common disorder characterized by pauses in regular breathing. Apneic episodes lead to recurrent hypoxemia-reoxygenation cycles with concomitant cellular intermittent hypoxia. Studies suggest that intermittent hypoxia in OSA may influence tumorigenesis. This review presents recent articles on the potential role of OSA in cancer development. Relevant research has focused on: molecular pathways mediating the influence of intermittent hypoxia on tumor physiology, animal and epidemiological human studies linking OSA and cancer. Current data relating OSA to risk of neoplastic disease remain scarce, but recent studies reveal the potential for a strong relation. More work is, therefore, needed on the impact of OSA on many cancer-related aspects. Results may offer enlightenment for improved cancer diagnosis and treatment.

  17. Uncoupling of Vascular Nitric Oxide Synthase Caused by Intermittent Hypoxia

    Directory of Open Access Journals (Sweden)

    Mohammad Badran

    2016-01-01

    Full Text Available Objective. Obstructive sleep apnea (OSA, characterized by chronic intermittent hypoxia (CIH, is often present in diabetic (DB patients. Both conditions are associated with endothelial dysfunction and cardiovascular disease. We hypothesized that diabetic endothelial dysfunction is further compromised by CIH. Methods. Adult male diabetic (BKS.Cg-Dock7m +/+ Leprdb/J (db/db mice (10 weeks old and their heterozygote littermates were subjected to CIH or intermittent air (IA for 8 weeks. Mice were separated into 4 groups: IA (intermittent air nondiabetic, IH (intermittent hypoxia nondiabetic, IADB (intermittent air diabetic, and IHDB (intermittent hypoxia diabetic groups. Endothelium-dependent and endothelium-independent relaxation and modulation by basal nitric oxide (NO were analyzed using wire myograph. Plasma 8-isoprostane, interleukin-6 (IL-6, and asymmetric dimethylarginine (ADMA were measured using ELISA. Uncoupling of eNOS was measured using dihydroethidium (DHE staining. Results. Endothelium-dependent vasodilation and basal NO production were significantly impaired in the IH and IADB group compared to IA group but was more pronounced in IHDB group. Levels of 8-isoprostane, IL-6, ADMA, and eNOS uncoupling were ≈2-fold higher in IH and IADB groups and were further increased in the IHDB group. Conclusion. Endothelial dysfunction is more pronounced in diabetic mice subjected to CIH compared to diabetic or CIH mice alone. Oxidative stress, ADMA, and eNOS uncoupling were exacerbated by CIH in diabetic mice.

  18. Social Smoking among Intermittent Smokers

    Science.gov (United States)

    Shiffman, Saul; Li, Xiaoxue; Dunbar, Michael S.; Ferguson, Stuart G.; Tindle, Hilary A.; Scholl, Sarah M.

    2015-01-01

    Background “Social smoking” - smoking mostly or even only with others – may be an important pattern that implies smoking motivated extrinsically by social influences. Non-daily smokers (intermittent smokers; ITS) are often assumed to be social smokers, with some authors even assuming that all ITS are social smokers (SS+). We sought to identify and characterize social smokers in a sample of ITS. Methods 204 adult ITS (smoking 4–27 days/month) recorded the circumstances of smoking in their natural settings using Ecological Momentary Assessment, while also recording their circumstances in nonsmoking moments. SS+ were defined as ITS who were with others when they smoked most of their cigarettes, and who were ≥ 50% more likely to be with others when smoking than when not. Results Only 13% of ITS were SS+. Although defined solely on the basis of presence of others, SS+ showed a distinct pattern of smoking across multiple dimensions: Compared to other ITS (who were significantly less likely to smoke when with others), SS+ smoking was more associated with socializing, being with friends and acquaintances, drinking alcohol, weekends, evening or nighttime, being in other people’s homes, but not their own home. SS+ smoking was low in the morning and increased in the evening. SS+ smoked fewer days/week and were less dependent, but did not differ demographically. Conclusions Social smoking does constitute a highly distinct smoking pattern, but is not common among adult ITS. PMID:26205313

  19. A comparative study on life cycle assessment of micro and macro components

    DEFF Research Database (Denmark)

    Omidvarnia, Farzaneh; Islam, Aminul; Hansen, Hans Nørgaard

    2013-01-01

    their smaller dimensional scale. So performing of LCA for micro products is equally important as it is for macro products. Keeping this motivation in mind, current paper systematically performs the LCA of a micro Socket used in hearing aids. The analysis makes a guide line about how to use the conventional...... knowledge about LCA and tools for the efficient LCA analysis of the micro parts. A comparative study is made in the paper by comparing two different sockets of hearing aid and it shows well how to make a comparative study for LCAwhen the manufacturer makes a new product to replace an old one. Another...

  20. Comparing the Life Cycle Energy Consumption, Global Warming and Eutrophication Potentials of Several Water and Waste Service Options

    Directory of Open Access Journals (Sweden)

    Xiaobo Xue

    2016-04-01

    Full Text Available Managing the water-energy-nutrient nexus for the built environment requires, in part, a full system analysis of energy consumption, global warming and eutrophication potentials of municipal water services. As an example, we evaluated the life cycle energy use, greenhouse gas (GHG emissions and aqueous nutrient releases of the whole anthropogenic municipal water cycle starting from raw water extraction to wastewater treatment and reuse/discharge for five municipal water and wastewater systems. The assessed options included conventional centralized services and four alternative options following the principles of source-separation and water fit-for-purpose. The comparative life cycle assessment identified that centralized drinking water supply coupled with blackwater energy recovery and on-site greywater treatment and reuse was the most energy- and carbon-efficient water service system evaluated, while the conventional (drinking water and sewerage centralized system ranked as the most energy- and carbon-intensive system. The electricity generated from blackwater and food residuals co-digestion was estimated to offset at least 40% of life cycle energy consumption for water/waste services. The dry composting toilet option demonstrated the lowest life cycle eutrophication potential. The nutrients in wastewater effluent are the dominating contributors for the eutrophication potential for the assessed system configurations. Among the parameters for which variability and sensitivity were evaluated, the carbon intensity of the local electricity grid and the efficiency of electricity production by the co-digestion with the energy recovery process were the most important for determining the relative global warming potential results.

  1. Comparative exergoeconomic analysis for cryogenic cycles of pilot plant for tritium and deuterium separation

    International Nuclear Information System (INIS)

    Gherghinescu, Sorin

    2008-01-01

    Full text: In modern society it is found that the ultimate aim of any economic production or services is to obtain profits, products made or services are only intermediate stages of the process of obtaining a profit. In various research activities engineers and scientists are concerned and wish to solve only the so-called 'technical problem' without having always in mind the economic aspect. The above mentioned need led to occurrence in the last 20 years of the thermoeconomy as an interdisciplinary science. The aim of the paper is to illustrate a model applicable to the analysis in cryogenic equipment able to extend technical problems through economic analysis in terms of scientific development, pointing out that any payment product or service is related not only their cost, but also their quality. It is also mindful of the fact that in research projects any payment is made only after a careful prospecting of the market that is what has been achieved by optimizing the cost / quality. The model is developed on the cycles of helium and hydrogen related to the same equipment. (author)

  2. Floodplain trapping and cycling compared to streambank erosion of sediment and nutrients in an agricultural watershed

    Science.gov (United States)

    Gillespie, Jaimie; Noe, Gregory; Hupp, Cliff R.; Gellis, Allen; Schenk, Edward R.

    2018-01-01

    Floodplains and streambanks can positively and negatively influence downstream water quality through interacting geomorphic and biogeochemical processes. Few studies have measured those processes in agricultural watersheds. We measured inputs (floodplain sedimentation and dissolved inorganic loading), cycling (floodplain soil nitrogen [N] and phosphorus [P] mineralization), and losses (bank erosion) of sediment, N, and P longitudinally in stream reaches of Smith Creek, an agricultural watershed in the Valley and Ridge physiographic province. All study reaches were net depositional (floodplain deposition > bank erosion), had high N and P sedimentation and loading rates to the floodplain, high soil concentrations of N and P, and high rates of floodplain soil N and P mineralization. High sediment, N, and P inputs to floodplains are attributed to agricultural activity in the region. Rates of P mineralization were much greater than those measured in other studies of nontidal floodplains that used the same method. Floodplain connectivity and sediment deposition decreased longitudinally, contrary to patterns in most watersheds. The net trapping function of Smith Creek floodplains indicates a benefit to water quality. Further research is needed to determine if future decreases in floodplain deposition, continued bank erosion, and the potential for nitrate leaching from nutrient-enriched floodplain soils could pose a long-term source of sediment and nutrients to downstream rivers.

  3. A Comparative Assessment of Life-Cycle Greenhouse Gas Emissions from Hypothetical Electric Airport Transportation Services in Thailand

    Science.gov (United States)

    Koiwanit, J.

    2018-05-01

    Global warming is an increase of average temperature in the atmosphere, which causes adverse effects on the environment. Carbon dioxide (CO2) from transportation sector is one of the main contributors of the overall greenhouse gases (GHG). To cope with this issue, electric car services are increasingly seen as popular alternative modes of green transportation especially for urban cities as it is more flexible, more environmentally-friendly, and less expensive than the use of conventional vehicles. The study analyses and compare the hypothetical electric car systems from airport transportation services. Center of Environmental Science of Leiden University (CML) 2001, the Life Cycle Impact Assessment (LCIA) method, is applied to convert life cycle inventory data into environmental impacts. The observed results showed that the electric shuttle bus had the highest impact in global warming potential (GWP) compared to other transportation types. Alternatively, this Life Cycle Assessment (LCA) study that evaluated different transportations provided important information for decision makers on quantifying the differences between each scenario.

  4. Comparative alternative materials assessment to screen toxicity hazards in the life cycle of CIGS thin film photovoltaics

    International Nuclear Information System (INIS)

    Eisenberg, Daniel A.; Yu, Mengjing; Lam, Carl W.; Ogunseitan, Oladele A.; Schoenung, Julie M.

    2013-01-01

    Highlights: • Comparative alternatives assessment of thin film manufacturing technologies. • Development of chemical alternatives assessment in a life cycle context. • Screening of manufacturing and solar cell hazardous substances simultaneously. -- Abstract: Copper–indium–gallium–selenium–sulfide (CIGS) thin film photovoltaics are increasingly penetrating the market supply for consumer solar panels. Although CIGS is attractive for producing less greenhouse gas emissions than fossil-fuel based energy sources, CIGS manufacturing processes and solar cell devices use hazardous materials that should be carefully considered in evaluating and comparing net environmental benefits of energy products. Through this research, we present a case study on the toxicity hazards associated with alternative materials selection for CIGS manufacturing. We applied two numeric models, The Green Screen for Safer Chemicals™ and the Toxic Potential Indicator. To improve the sensitivity of the model outputs, we developed a novel, life cycle thinking based hazard assessment method that facilitates the projection of hazards throughout material life cycles. Our results show that the least hazardous CIGS solar cell device and manufacturing protocol consist of a titanium substrate, molybdenum metal back electrode, CuInS 2 p-type absorber deposited by spray pyrolysis, ZnS buffer deposited by spray ion layer gas reduction, ZnO:Ga transparent conducting oxide (TCO) deposited by sputtering, and the encapsulant polydimethylsiloxane

  5. Comparative alternative materials assessment to screen toxicity hazards in the life cycle of CIGS thin film photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Eisenberg, Daniel A.; Yu, Mengjing; Lam, Carl W. [University of California, Davis, 1 Shields Avenue, Davis, CA 95616 (United States); Ogunseitan, Oladele A. [University of California, Irvine, Irvine, CA 92697 (United States); Schoenung, Julie M., E-mail: jmschoenung@ucdavis.edu [University of California, Davis, 1 Shields Avenue, Davis, CA 95616 (United States)

    2013-09-15

    Highlights: • Comparative alternatives assessment of thin film manufacturing technologies. • Development of chemical alternatives assessment in a life cycle context. • Screening of manufacturing and solar cell hazardous substances simultaneously. -- Abstract: Copper–indium–gallium–selenium–sulfide (CIGS) thin film photovoltaics are increasingly penetrating the market supply for consumer solar panels. Although CIGS is attractive for producing less greenhouse gas emissions than fossil-fuel based energy sources, CIGS manufacturing processes and solar cell devices use hazardous materials that should be carefully considered in evaluating and comparing net environmental benefits of energy products. Through this research, we present a case study on the toxicity hazards associated with alternative materials selection for CIGS manufacturing. We applied two numeric models, The Green Screen for Safer Chemicals™ and the Toxic Potential Indicator. To improve the sensitivity of the model outputs, we developed a novel, life cycle thinking based hazard assessment method that facilitates the projection of hazards throughout material life cycles. Our results show that the least hazardous CIGS solar cell device and manufacturing protocol consist of a titanium substrate, molybdenum metal back electrode, CuInS{sub 2} p-type absorber deposited by spray pyrolysis, ZnS buffer deposited by spray ion layer gas reduction, ZnO:Ga transparent conducting oxide (TCO) deposited by sputtering, and the encapsulant polydimethylsiloxane.

  6. Comparative study on life cycle environmental impact assessment of copper and aluminium cables

    Science.gov (United States)

    Bao, Wei; Lin, Ling; Song, Dan; Guo, Huiting; Chen, Liang; Sun, Liang; Liu, Mei; Chen, Jianhua

    2017-11-01

    With the rapid development of industrialization and urbanization in China, domestic demands for copper and aluminium resources increase continuously and the output of copper and aluminium minerals rises steadily. The output of copper in China increased from 0.6 million tons (metal quantity) in 2003 to 1.74 million tons (metal quantity) in 2014, and the output of bauxite increased from 21 million tons in 2006 to 59.21 million tons in 2014. In the meantime, the import of copper and aluminium minerals of China is also on a rise. The import of copper concentrate and bauxite increased from 4.94 million tons and 9.68 million tons in 2006 to 10.08 million tons and 70.75 million tons in 2013 respectively. Copper and aluminium resources are widely applied in fields such as construction, electrical and electronics, machinery manufacturing, and transportation, and serve as important material basis for the national economic and social development of China. Cable industry is a typical industry where copper and aluminium resources are widely used. In this paper, a product assessment model is built from the perspective of product life cycle. Based on CNLCD database, differences in environmental impacts of copper and aluminium cables are analyzed from aspects such as resource acquisition, product production, transportation, utilization, and resource recycling. Furthermore, the advantages and disadvantages of products at different stages with different types of environmental impact are analyzed, so as to provide data support for cable industry in terms of product design and production, etc.

  7. A comparative study on nutrient cycling in wet heathland ecosystems : II. Litter decomposition and nutrient mineralization.

    Science.gov (United States)

    Berendse, Frank; Bobbink, Roland; Rouwenhorst, Gerrit

    1989-03-01

    The concept of the relative nutrient requirement (L n ) that was introduced in the first paper of this series is used to analyse the effects of the dominant plant population on nutrient cycling and nutrient mineralization in wet heathland ecosystems. A distinction is made between the effect that the dominant plant species has on (1) the distribution of nutrients over the plant biomass and the soil compartment of the ecosystem and (2) the recirculation rate of nutrients. The first effect of the dominant plant species can be calculated on the basis of the δ/k ratio (which is the ratio of the relative mortality to the decomposition constant). The second effect can be analysed using the relative nutrient requirement (L n ). The mass loss and the changes in the amounts of N and P in decomposing above-ground and below-ground litter produced by Erica tetralix and Molinia caerulea were measured over three years. The rates of mass loss from both above-ground and below-ground litter of Molinia were higher than those from Erica litter. After an initial leaching phase, litter showed either a net release or a net immobilization of nitrogen or phosphorus that depended on the initial concentrations of these nutrients. At the same sites, mineralization of nitrogen and phosphorus were measured for two years both in communities dominated by Molinia and in communities dominated by Erica. There were no clear differences in the nitrogen mineralization, but in one of the two years, phosphate mineralization in the Molinia-community was significantly higher. On the basis of the theory that was developed, mineralization rates and ratios between amounts of nutrients in plant biomass and in the soil were calculated on the basis of parameters that were independently measured. There was a reasonable agreement between predicted and measured values in the Erica-communities. In the Molinia-communities there were large differences between calculated and measured values, which was explained by the

  8. Accelerated anaerobic hydrolysis rates under a combination of intermittent aeration and anaerobic conditions

    DEFF Research Database (Denmark)

    Jensen, T. R.; Lastra Milone, T.; Petersen, G.

    2017-01-01

    Anaerobic hydrolysis in activated return sludge was investigated in laboratory scale experiments to find if intermittent aeration would accelerate anaerobic hydrolysis rates compared to anaerobic hydrolysis rates under strict anaerobic conditions. The intermittent reactors were set up in a 240 h...... for calculating hydrolysis rates based on soluble COD were compared. Two-way ANOVA with the Bonferroni post-test was performed in order to register any significant difference between reactors with intermittent aeration and strictly anaerobic conditions respectively. The experiment demonstrated a statistically...... significant difference in favor of the reactors with intermittent aeration showing a tendency towards accelerated anaerobic hydrolysis rates due to application of intermittent aeration. The conclusion of the work is thus that intermittent aeration applied in the activated return sludge process (ARP) can...

  9. Comparative Environmental Life Cycle Assessment of Alternative Uses of Wastewater Carbon Content

    DEFF Research Database (Denmark)

    Kroghsbo, Nena; Nicolaisen, Janna; Wenzel, Henrik

    Alternative scenarios for the wastewater and sludge treatment configurations in urban wastewater treatment were studied with the aim of comparing their environmental aspects. As the reference, a conventional activated sludge treatment was chosen including a primary settling and biogas made from...... the mixed primary and secondary sludge. This reference was then compared to an alternative use of the mixed sludge for the fermentative generation of polyhydroxyalkanoates, PHA and subsequent use of the PHA to substitute polypropylene on the polymer markets. This comparison allows for assessing...... the environmental priorities between biogas and PHA formation from the carbon content of the sludge. Further, the elimination of the primary settling with the aim of using the carbon content of the wastewater for enhanced nitrogen removal in the activated sludge process was studied. This comparison allows...

  10. A comparative physics study of alternative long-term strategies for closure of the nuclear fuel cycle

    International Nuclear Information System (INIS)

    Cometto, M.; Wydler, P.; Chawla, R.

    2004-01-01

    The appropriate management of radioactive waste arising from the nuclear fuel cycle is considered to be a key issue in the development of future, more sustainable nuclear energy systems. In this context, the partitioning and transmutation of actinides could play an important role through the achievement of very significant reductions in the actinide content and radiotoxicity of the high-level waste requiring geological disposal. The current paper reports on the results of a detailed physics study carried out to compare the pros and cons of alternative strategies for closure of the nuclear fuel cycle. Different long-term 'steady-state' scenarios have been considered, involving the deployment, to varying degrees, of light water reactors (LWRs) and advanced fast-spectrum systems. The same nuclear data and calculation methods have been used throughout, so that a consistent and reliable comparison of the relative performance of the three basic fuel cycle options (once-through, plutonium recycle, and recycling of all actinides) has been made possible. In addition, with transmutation having been considered employing both critical and accelerator-driven fast-spectrum systems, the study has provided an evaluation of the advantages and disadvantages of these two different advanced system types

  11. Sun in the Epoch ``LOWERED'' Solar Activity: the Comparative Analysis of the Current 24 Solar Cycle and Past Authentic Low Cycles

    Science.gov (United States)

    Vitaly, Ishkov

    A reliable series of the relative numbers of sunspots (14 solar cycles ‒ 165 years) it leads to the only scenario of solar activity cycles - to the alternation of epochs of “increased” (18 ‒ 22 cycles of solar activity) and “lowered” (12 ‒ 16 and 24 ‒ ...) solar activity with the periods of solar magnetic field reconstruction in solar zone of the sunspots formation (11, 12, 23) from one epoch to another. The regime of the produce of magnetic field significantly changes in these periods, providing to the subsequent 5 cycles the stable conditions of solar activity. Space solar research made it possible to sufficiently fully investigate characteristics and parameters of the solar cycles for the epoch of “increased” (20 ‒ 22 cycles) solar activity and period of the reconstruction (22 ‒ 23 cycles) to the epoch of “lowered” solar activity (24 ‒ ... cycles). In this scenario 24 solar cycle is the first solar cycle of the second epoch of “lowered” solar activity. Therefore his development and characteristics roughly must be described in the context of the low solar cycles development (12, 14, and 16). In the current solar cycle the sunspot-forming activity is lowered, the average areas of the sunspot groups correspond to values for epoch of “lowered “solar activity, average magnetic field in the umbra of sunspots was reduced approximately to 700 gauss, and for this time was observed only 4 very large sunspot groups (≥1500 mvh). Flare activity substantially was lowered: for the time of the current solar cycle development it was occurrence of M-class flares M - 368, class X - 32, from which only 2 solar flares of class X> 5. Solar proton events are observed predominantly small intensity; but only 5 from them were the intensity of ≥100 pfu (S2) and 4 - ≥1000 pfu (S3). The first five years of the 24 cycle evolution confirm this assumption and the possibility to give the qualitative forecast of his evolution and development of the

  12. Using the Reliability Theory for Assessing the Decision Confidence Probability for Comparative Life Cycle Assessments.

    Science.gov (United States)

    Wei, Wei; Larrey-Lassalle, Pyrène; Faure, Thierry; Dumoulin, Nicolas; Roux, Philippe; Mathias, Jean-Denis

    2016-03-01

    Comparative decision making process is widely used to identify which option (system, product, service, etc.) has smaller environmental footprints and for providing recommendations that help stakeholders take future decisions. However, the uncertainty problem complicates the comparison and the decision making. Probability-based decision support in LCA is a way to help stakeholders in their decision-making process. It calculates the decision confidence probability which expresses the probability of a option to have a smaller environmental impact than the one of another option. Here we apply the reliability theory to approximate the decision confidence probability. We compare the traditional Monte Carlo method with a reliability method called FORM method. The Monte Carlo method needs high computational time to calculate the decision confidence probability. The FORM method enables us to approximate the decision confidence probability with fewer simulations than the Monte Carlo method by approximating the response surface. Moreover, the FORM method calculates the associated importance factors that correspond to a sensitivity analysis in relation to the probability. The importance factors allow stakeholders to determine which factors influence their decision. Our results clearly show that the reliability method provides additional useful information to stakeholders as well as it reduces the computational time.

  13. Intermittent Fasting Modulation of the Diabetic Syndrome in Streptozotocin-Injected Rats

    OpenAIRE

    Louiza Belkacemi; Ghalem Selselet-Attou; Emeline Hupkens; Evrard Nguidjoe; Karim Louchami; Abdullah Sener; Willy J. Malaisse

    2012-01-01

    This study investigates the effects of intermittent overnight fasting in streptozotocin-induced diabetic rats (STZ rats). Over 30 days, groups of 5-6 control or STZ rats were allowed free food access, starved overnight, or exposed to a restricted food supply comparable to that ingested by the intermittently fasting animals. Intermittent fasting improved glucose tolerance, increased plasma insulin, and lowered Homeostatis Model Assessment index. Caloric restriction failed to cause such benefic...

  14. Do cycle disturbances explain the age-related decline of female fertility? Cycle characteristics of women aged over 40 years compared with a reference population of young women.

    NARCIS (Netherlands)

    Zonneveld, P. van; Scheffer, G.J.; Broekmans, F.J.; Blankenstein, M.A.; Jong, F.H. de; Looman, C.W.; Habbema, J.D.F.; Velde, E.R. te

    2003-01-01

    BACKGROUND: The cause of declining fertility with age, in women who still have regular menstrual cycles, is not clear. METHODS: Follicle development, endometrial growth and hormonal patterns were evaluated in cycles of older women (aged 41-46 years; n = 26) who previously were normally fertile, and

  15. Intermittent versus continuous exercise training in chronic heart failure: a meta-analysis.

    Science.gov (United States)

    Smart, Neil A; Dieberg, Gudrun; Giallauria, Francesco

    2013-06-20

    We conducted a meta-analysis of randomized, controlled trials of combined strength and intermittent aerobic training, intermittent aerobic training only and continuous exercise training in heart failure patients. A systematic search was conducted of Medline (Ovid) (1950-September 2011), Embase.com (1974-September 2011), Cochrane Central Register of Controlled Trials and CINAHL (1981-September 19 2011). The search strategy included a mix of MeSH and free text terms for the key concepts heart failure, exercise training, interval training and intermittent exercise training. The included studies contained an aggregate of 446 patients, 212 completed intermittent exercise training, 66 only continuous exercise training, 59 completed combined intermittent and strength training and 109 sedentary controls. Weighted mean difference (MD) in Peak VO2 was 1.04mlkg(-1)min(-1) and (95% C.I.) was 0.42-1.66 (p=0.0009) in intermittent versus continuous exercise training respectively. Weighted mean difference in Peak VO2 was -1.10mlkg(-1)min(-1) (95% C.I.) was -1.83-0.37 p=0.003 for intermittent only versus intermittent and strength (combined) training respectively. In studies reporting VE/VCO2 for intermittent versus control groups, MD was -1.50 [(95% C.I. -2.64, -0.37), p=0.01] and for intermittent versus continuous exercise training MD was -1.35 [(95% C.I. -2.15, -0.55), p=0.001]. Change in peak VO2 was positively correlated with weekly exercise energy expenditure for intermittent exercise groups (r=0.48, p=0.05). Combined strength and intermittent exercise appears superior for peak VO2 changes when compared to intermittent exercise of similar exercise energy expenditure. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  16. Intermittent metabolic switching, neuroplasticity and brain health

    Science.gov (United States)

    Mattson, Mark P.; Moehl, Keelin; Ghena, Nathaniel; Schmaedick, Maggie; Cheng, Aiwu

    2018-01-01

    During evolution, individuals whose brains and bodies functioned well in a fasted state were successful in acquiring food, enabling their survival and reproduction. With fasting and extended exercise, liver glycogen stores are depleted and ketones are produced from adipose-cell-derived fatty acids. This metabolic switch in cellular fuel source is accompanied by cellular and molecular adaptations of neural networks in the brain that enhance their functionality and bolster their resistance to stress, injury and disease. Here, we consider how intermittent metabolic switching, repeating cycles of a metabolic challenge that induces ketosis (fasting and/or exercise) followed by a recovery period (eating, resting and sleeping), may optimize brain function and resilience throughout the lifespan, with a focus on the neuronal circuits involved in cognition and mood. Such metabolic switching impacts multiple signalling pathways that promote neuroplasticity and resistance of the brain to injury and disease. PMID:29321682

  17. A comparative life cycle assessment of diesel and compressed natural gas powered refuse collection vehicles in a Canadian city

    International Nuclear Information System (INIS)

    Rose, Lars; Hussain, Mohammed; Ahmed, Syed; Malek, Kourosh; Costanzo, Robert; Kjeang, Erik

    2013-01-01

    Consumers and organizations worldwide are searching for low-carbon alternatives to conventional gasoline and diesel vehicles to reduce greenhouse gas (GHG) emissions and their impact on the environment. A comprehensive technique used to estimate overall cost and environmental impact of vehicles is known as life cycle assessment (LCA). In this article, a comparative LCA of diesel and compressed natural gas (CNG) powered heavy duty refuse collection vehicles (RCVs) is conducted. The analysis utilizes real-time operational data obtained from the City of Surrey in British Columbia, Canada. The impact of the two alternative vehicles is assessed from various points in their life. No net gain in energy use is found when a diesel powered RCV is replaced by a CNG powered RCV. However, significant reductions (approximately 24% CO 2 -equivalent) in GHG and criteria air contaminant (CAC) emissions are obtained. Moreover, fuel cost estimations based on 2011 price levels and a 5-year lifetime for both RCVs reveal that considerable cost savings may be achieved by switching to CNG vehicles. Thus, CNG RCVs are not only favorable in terms of reduced climate change impact but also cost effective compared to conventional diesel RCVs, and provide a viable and realistic near-term strategy for cities and municipalities to reduce GHG emissions. - Highlights: ► Life cycle analysis is performed on two alternative refuse collection vehicle technologies. ► Real-time operational data obtained by the City of Surrey in British Columbia are utilized. ► The life cycle energy use is similar for diesel and CNG RCVs. ► A 24% reduction of GHG emissions (CO 2 -equivalent) may be realized by switching from diesel to CNG. ► CNG RCVs are estimated to be cost effective and may lead to reduced fuel costs.

  18. Comparative Study on Solar Collector’s Configuration for an Ejector-Refrigeration Cycle

    Directory of Open Access Journals (Sweden)

    Raffles Senjaya

    2008-05-01

    Full Text Available Solar collector’s configuration plays important role on solar-powered refrigeration systems to work as heat source for generator. Three types of solar collector consisting of flat plate, evacuated tube, and compound parabolic solar collectors are compared to investigate their performances. The performances consist of the behavior of heat which can be absorbed by the collectors, heat loss from the collectors and outlet temperature of working fluid at several slopes of the solar collectors. The new accurate analysis method of heat transfer is conducted to predict the performance of the solar collectors. The analysis is based on several assumptions, i.e. sky condition at Bandung is clear and not raining from 08.00 until 17.00 and thermal resistance at cover and absorber plate is negligible. The numerical calculation results confirm that performance of the evacuated tubes solar collector at the same operating conditions is higher than the others. For the case of an evacuated-tubes solar collector system with aperture area of 3.5 m2, the maximum heat which can be absorbed is 3992 W for the highest solar intensity of 970 W/m2 at 12.00 and horizontal position of the solar collector. At this condition, the highest outlet temperature of water is 347.15 K with mass flow rate 0.02 kg/s and inlet temperature 298 K.

  19. Radioactivity of uranium production cycle facilities in the Czech Republic compared to the natural environment

    International Nuclear Information System (INIS)

    Matolin, M.

    2002-01-01

    Forty-five years (1946-1990) of intensive uranium exploration and exploitation in the Czech Republic led to mining at 64 uranium deposits. These mining and milling activities left numerous accumulations of waste rock material in the landscape. The radioactivity of these man-made accumulations was measured and compared to the natural radiation environment. Waste rock dumps at the uranium deposits Pribram, Rozna, Jachymov, Straz-Hamr and deposits in the Zelezne Hory area show surface gamma dose rates mostly in the range of 200-1000 nGy/h, with a uranium concentration 10-100 ppm eU. An extremely high radioactivity of 3000-4200 nGy/h was detected at the extensive uranium processing tailings impoundments at Straz. Terrestrial gamma dose rate of regional geological units in the Czech Republic is in the range of 6-245 nGy/h. Reclamation and recultivation of dumps, control of their radioactivity and restriction of their accessibility are the major measures introduced to protect the public. (author)

  20. Mechanisms affecting water quality in an intermittent piped water supply.

    Science.gov (United States)

    Kumpel, Emily; Nelson, Kara L

    2014-01-01

    Drinking water distribution systems throughout the world supply water intermittently, leaving pipes without pressure between supply cycles. Understanding the multiple mechanisms that affect contamination in these intermittent water supplies (IWS) can be used to develop strategies to improve water quality. To study these effects, we tested water quality in an IWS system with infrequent and short water delivery periods in Hubli-Dharwad, India. We continuously measured pressure and physicochemical parameters and periodically collected grab samples to test for total coliform and E. coli throughout supply cycles at 11 sites. When the supply was first turned on, water with elevated turbidity and high concentrations of indicator bacteria was flushed out of pipes. At low pressures (water was delivered with a chlorine residual and at pressures >17 psi.

  1. Comparative analyses of forest fuels in a life cycle perspective with a focus on transport systems

    Energy Technology Data Exchange (ETDEWEB)

    Eriksson, Lisa Naeslund [Ecotechnology, Department of Engineering, Physics and Mathematics, Mid Sweden University, SE-831 25 Oestersund (Sweden)

    2008-08-15

    Local, national and international transportation of forest fuels with regard to costs, primary energy use and CO{sub 2} emission was analysed. The main issue was the extent to which both mode and distance of transport affect the monetary cost, CO{sub 2} emission and primary energy use arising from the use of various types of forest residues for energy purpose. Local applications proved the most efficient options of those studied. Chipping of bundles at a terminal, for transport by rail and sea to national or international end-users, has low costs and produces only modest CO{sub 2} emissions. For the pellet options, the cost is about the same as for chipping, but require more primary energy and emit more CO{sub 2}. The traditional chipping system is more expensive than the other options. The costs of the international options over a transport distance of 1100 km vary between 21 and 28 EUR{sub 2007}/MWh, whereas pellet options cost between 22 and 25 EUR{sub 2007}/MWh. The primary energy required for transport of logging residues vis-a-vis pellets falls in the range 4-7% and 2-4%, respectively, of the bio-energy delivered. The primary energy needed to produce pellets gives them a lower fossil fuel substitution rate per hectare, compared with bundle systems. Similarly, for chip systems vis-a-vis bundle systems, the biomass delivered to the conversion plant is reduced by the greater physical dry-matter losses entailed by chipping systems in the forest-fuel chain. (author)

  2. Comparative gene expression analysis throughout the life cycle of Leishmania braziliensis: diversity of expression profiles among clinical isolates.

    Directory of Open Access Journals (Sweden)

    Vanessa Adaui

    Full Text Available BACKGROUND: Most of the Leishmania genome is reported to be constitutively expressed during the life cycle of the parasite, with a few regulated genes. Inter-species comparative transcriptomics evidenced a low number of species-specific differences related to differentially distributed genes or the differential regulation of conserved genes. It is of uppermost importance to ensure that the observed differences are indeed species-specific and not simply specific of the strains selected for representing the species. The relevance of this concern is illustrated by current study. METHODOLOGY/PRINCIPAL FINDINGS: We selected 5 clinical isolates of L. braziliensis characterized by their diversity of clinical and in vitro phenotypes. Real-time quantitative PCR was performed on promastigote and amastigote life stages to assess gene expression profiles at seven time points covering the whole life cycle. We tested 12 genes encoding proteins with roles in transport, thiol-based redox metabolism, cellular reduction, RNA poly(A-tail metabolism, cytoskeleton function and ribosomal function. The general trend of expression profiles showed that regulation of gene expression essentially occurs around the stationary phase of promastigotes. However, the genes involved in this phenomenon appeared to vary significantly among the isolates considered. CONCLUSION/SIGNIFICANCE: Our results clearly illustrate the unique character of each isolate in terms of gene expression dynamics. Results obtained on an individual strain are not necessarily representative of a given species. Therefore, extreme care should be taken when comparing the profiles of different species and extrapolating functional differences between them.

  3. Comparative life cycles and life histories of North American Rhabdias spp. (Nematoda: Rhabdiasidae): lungworms from snakes and anurans.

    Science.gov (United States)

    Langford, Gabriel J; Janovy, John

    2009-10-01

    The present study used experimental infections to compare the life cycles and life histories of 6 Rhabdias spp. infecting snakes and anurans. Free-living development of anuran lungworms was primarily limited to heterogonic reproduction, and females utilized matricidal endotoky exclusively, whereas snake lungworms primarily reproduced homogonically and, when heterogonic reproduction occurred, females used a combination of releasing eggs and matricidal endotoky. Infective snake lungworms survived for longer periods in fresh water compared to anuran worms. Infective anuran lungworms penetrated into the skin of frogs and toads; few infections resulted from per os infections. In contrast, snake lungworms were unable to penetrate skin; instead, infective juveniles penetrated into snake esophageal tissue during per os infections. Despite separate points of entry, anuran and snake lungworms both migrated and developed in the fascia, eventually penetrating into the body cavity of the host. Worms molted to adulthood inside the body cavity and subsequently penetrated into the host's lungs, where they fed on blood while becoming gravid. Adult lungworm survival varied among lungworm species, but, in general, snake lungworms were longer lived than anuran worms. Anuran lungworms were poorly suited for transmission via transport hosts, whereas snake lungworms were consistently capable of establishing infections using transport hosts. Overall, these observations suggest that snake and anuran lungworms have discrepant life cycles and life history strategies.

  4. Life Cycle Assessment and Costing Methods for Device Procurement: Comparing Reusable and Single-Use Disposable Laryngoscopes.

    Science.gov (United States)

    Sherman, Jodi D; Raibley, Lewis A; Eckelman, Matthew J

    2018-01-09

    Traditional medical device procurement criteria include efficacy and safety, ease of use and handling, and procurement costs. However, little information is available about life cycle environmental impacts of the production, use, and disposal of medical devices, or about costs incurred after purchase. Reusable and disposable laryngoscopes are of current interest to anesthesiologists. Facing mounting pressure to quickly meet or exceed conflicting infection prevention guidelines and oversight body recommendations, many institutions may be electively switching to single-use disposable (SUD) rigid laryngoscopes or overcleaning reusables, potentially increasing both costs and waste generation. This study provides quantitative comparisons of environmental impacts and total cost of ownership among laryngoscope options, which can aid procurement decision making to benefit facilities and public health. We describe cradle-to-grave life cycle assessment (LCA) and life cycle costing (LCC) methods and apply these to reusable and SUD metal and plastic laryngoscope handles and tongue blade alternatives at Yale-New Haven Hospital (YNHH). The US Environmental Protection Agency's Tool for the Reduction and Assessment of Chemical and other environmental Impacts (TRACI) life cycle impact assessment method was used to model environmental impacts of greenhouse gases and other pollutant emissions. The SUD plastic handle generates an estimated 16-18 times more life cycle carbon dioxide equivalents (CO2-eq) than traditional low-level disinfection of the reusable steel handle. The SUD plastic tongue blade generates an estimated 5-6 times more CO2-eq than the reusable steel blade treated with high-level disinfection. SUD metal components generated much higher emissions than all alternatives. Both the SUD handle and SUD blade increased life cycle costs compared to the various reusable cleaning scenarios at YNHH. When extrapolated over 1 year (60,000 intubations), estimated costs increased

  5. Cycle ergometer and inspiratory muscle training offer modest benefit compared with cycle ergometer alone: a comprehensive assessment in stable COPD patients

    Directory of Open Access Journals (Sweden)

    Wang K

    2017-09-01

    Full Text Available Kai Wang,1,* Guang-qiao Zeng,2,* Rui Li,1,* Yu-wen Luo,1 Mei Wang,1 Yu-he Hu,1 Wen-hui Xu,1 Lu-qian Zhou,2 Rong-chang Chen,2 Xin Chen1 1Department of Respiratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, China; 2Department of Respiratory Medicine, The State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China *These authors contributed equally to this work Background: Cycle ergometer training (CET has been shown to improve exercise performance of the quadriceps muscles in patients with COPD, and inspiratory muscle training (IMT may improve the pressure-generating capacity of the inspiratory muscles. However, the effects of combined CET and IMT remain unclear and there is a lack of comprehensive assessment.Materials and methods: Eighty-one patients with COPD were randomly allocated to three groups: 28 received 8 weeks of CET + IMT (combined training group, 27 received 8 weeks of CET alone (CET group, and 26 only received 8 weeks of free walking (control group. Comprehensive assessment including respiratory muscle strength, exercise capacity, pulmonary function, dyspnea, quality of life, emotional status, nutritional status, and body mass index, airflow obstruction, and exercise capacity index were measured before and after the pulmonary rehabilitation program.Results: Respiratory muscle strength, exercise capacity, inspiratory capacity, dyspnea, quality of life, depression and anxiety, and nutritional status were all improved in the combined training and CET groups when compared with that in the control group (P<0.05 after pulmonary rehabilitation program. Inspiratory muscle strength increased significantly in the combined training group when compared with that in the CET group (ΔPImax [maximal inspiratory pressure] 5.20±0.89 cmH2O vs 1.32±0.91 cmH2O

  6. A Comparative Study of Cycle Variability of Laser Plug Ignition vs Classical Spark Plug Ignition in Combustion Engines

    Science.gov (United States)

    Done, Bogdan

    2017-10-01

    Over the past 30 years numerous studies and laboratory experiments have researched the use of laser energy to ignite gas and fuel-air mixtures. The actual implementation of this laser application has still to be fully achieved in a commercial automotive application. Laser Plug Ignition as a replacement for Spark Plug Ignition in the internal combustion engines of automotive vehicles, offers several potential benefits such as extending lean burn capability, reducing the cyclic variability between combustion cycles and decreasing the total amount of ignition costs, and implicitly weight and energy requirements. The paper presents preliminary results of cycle variability study carried on a SI Engine equipped with laser Plug Ignition system. Versus classic ignition system, the use of the laser Plug Ignition system assures the reduction of the combustion process variability, reflected in the lower values of the coefficient of variability evaluated for indicated mean effective pressure, maximum pressure, maximum pressure angle and maximum pressure rise rate. The laser plug ignition system was mounted on an experimental spark ignition engine and tested at the regime of 90% load and 2800 rev/min, at dosage of λ=1.1. Compared to conventional spark plug, laser ignition assures the efficiency at lean dosage.

  7. Comparative effects of ionizing radiation on cycle time and mitotic duration. A time-lapse cinematography study

    International Nuclear Information System (INIS)

    D'Hooghe, M.C.; Hemon, D.; Valleron, A.J.; Malaise, E.P.

    1980-01-01

    The effects of 60 Co γ rays on the length of the intermitotic period, the duration of mitosis, and the division probability of EMT6 cells have been studied in vitro using time-lapse cinematography. Irradiation increases the duration of the mitosis and of the cycle in comparable proportions: both parameters are practically doubled by a dose of 10 Gy. When daughters of irradiated cells die, the mitotic delay and lengthening of mitosis of their mother cells are longer than average. Mitotic delay and lengthening of mitosis depend on the age of cells at the moment of irradiation. The mitotic delay increases progressively when cells are irradiated during the first 8 h of their cycle (i.e., before the transition point), whereas mitosis is slightly prolonged. On the other hand, when the cells are irradiated after this transition point the mitotic delay decreases markedly, whereas the lengthening of mitosis increases sharply. These results tend to indicate that two different mechanisms are responsible for mitotic delay and prolongation of mitosis observed after irradiation

  8. Comparative effects of ionizing radiation on cycle time and mitotic duration. A time-lapse cinematography study

    Energy Technology Data Exchange (ETDEWEB)

    D' Hooghe, M.C. (Institut de Recherches sur le Cancer, Lille, France); Hemon, D.; Valleron, A.J.; Malaise, E.P.

    1980-03-01

    The effects of /sup 60/Co ..gamma.. rays on the length of the intermitotic period, the duration of mitosis, and the division probability of EMT6 cells have been studied in vitro using time-lapse cinematography. Irradiation increases the duration of the mitosis and of the cycle in comparable proportions: both parameters are practically doubled by a dose of 10 Gy. When daughters of irradiated cells die, the mitotic delay and lengthening of mitosis of their mother cells are longer than average. Mitotic delay and lengthening of mitosis depend on the age of cells at the moment of irradiation. The mitotic delay increases progressively when cells are irradiated during the first 8 h of their cycle (i.e., before the transition point), whereas mitosis is slightly prolonged. On the other hand, when the cells are irradiated after this transition point the mitotic delay decreases markedly, whereas the lengthening of mitosis increases sharply. These results tend to indicate that two different mechanisms are responsible for mitotic delay and prolongation of mitosis observed after irradiation.

  9. Comparative alternative materials assessment to screen toxicity hazards in the life cycle of CIGS thin film photovoltaics.

    Science.gov (United States)

    Eisenberg, Daniel A; Yu, Mengjing; Lam, Carl W; Ogunseitan, Oladele A; Schoenung, Julie M

    2013-09-15

    Copper-indium-gallium-selenium-sulfide (CIGS) thin film photovoltaics are increasingly penetrating the market supply for consumer solar panels. Although CIGS is attractive for producing less greenhouse gas emissions than fossil-fuel based energy sources, CIGS manufacturing processes and solar cell devices use hazardous materials that should be carefully considered in evaluating and comparing net environmental benefits of energy products. Through this research, we present a case study on the toxicity hazards associated with alternative materials selection for CIGS manufacturing. We applied two numeric models, The Green Screen for Safer Chemicals and the Toxic Potential Indicator. To improve the sensitivity of the model outputs, we developed a novel, life cycle thinking based hazard assessment method that facilitates the projection of hazards throughout material life cycles. Our results show that the least hazardous CIGS solar cell device and manufacturing protocol consist of a titanium substrate, molybdenum metal back electrode, CuInS₂ p-type absorber deposited by spray pyrolysis, ZnS buffer deposited by spray ion layer gas reduction, ZnO:Ga transparent conducting oxide (TCO) deposited by sputtering, and the encapsulant polydimethylsiloxane. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Drought and ecosystem carbon cycling

    NARCIS (Netherlands)

    Molen, M.K. van der; Dolman, A.J.; Ciais, P.; Eglin, T.; Gobron, N.; Law, B.E.; Meir, P.; Peters, P.; Philips, O.L.; Reichstein, M.; Chen, T.; Dekker, S.C.; Doubkova, M.; Friedl, M.A.; Jung, M.; Hurk, B.J.J.M. van den; Jeu, R.A.M. de; Kruijt, B.; Ohta, T.; Rebel, K.T.; Plummer, S.; Seneviratne, S.I.; Sitch, S.; Teuling, A.J.; Werf, G.R. van der; Wang, G.

    2011-01-01

    Drought as an intermittent disturbance of the water cycle interacts with the carbon cycle differently than the ‘gradual’ climate change. During drought plants respond physiologically and structurally to prevent excessive water loss according to species-specific water use strategies. This has

  11. Overjustification and Intermittent Reinforcement.

    Science.gov (United States)

    Stalling, Richard B.; And Others

    Within the area of attribution theory, an overjustification effect is inferred if, following reward for an intrinsically interesting activity, individuals subsequently show less interest in that activity than comparable individuals who receive no reward. In an attempt to isolate the overjustification effect, 60 college students (30 male, 30…

  12. Measuring and Comparing Descend in Elite Race Cycling with a Perspective on Real-Time Feedback for Improving Individual Performance

    Directory of Open Access Journals (Sweden)

    M. M. Reijne

    2018-02-01

    Full Text Available Descend technique and performance vary among elite racing cyclists and it is not clear what slower riders should do to improve their performance. An observation study was performed of the descending technique of members of a World Tour cycling team and the technique of each member was compared with the fastest descender amongst them. The obtained data gives us guidelines for rider specific feedback in order to improve his performance. The bicycles were equipped with a system that could measure: velocity, cadence, pedal power, position, steer angle, 3D orientation, rotational speeds and linear accelerations of the rear frame and brake force front and rear. From our observation study, the brake point and apex position turned out to be distinctive indicators of a fast cornering technique in a descent for a tight, hairpin corner. These two indicators can be used as feedback for a slower rider to improve his descend performance.

  13. Hovering and intermittent flight in birds

    International Nuclear Information System (INIS)

    Tobalske, Bret W

    2010-01-01

    Two styles of bird locomotion, hovering and intermittent flight, have great potential to inform future development of autonomous flying vehicles. Hummingbirds are the smallest flying vertebrates, and they are the only birds that can sustain hovering. Their ability to hover is due to their small size, high wingbeat frequency, relatively large margin of mass-specific power available for flight and a suite of anatomical features that include proportionally massive major flight muscles (pectoralis and supracoracoideus) and wing anatomy that enables them to leave their wings extended yet turned over (supinated) during upstroke so that they can generate lift to support their weight. Hummingbirds generate three times more lift during downstroke compared with upstroke, with the disparity due to wing twist during upstroke. Much like insects, hummingbirds exploit unsteady mechanisms during hovering including delayed stall during wing translation that is manifest as a leading-edge vortex (LEV) on the wing and rotational circulation at the end of each half stroke. Intermittent flight is common in small- and medium-sized birds and consists of pauses during which the wings are flexed (bound) or extended (glide). Flap-bounding appears to be an energy-saving style when flying relatively fast, with the production of lift by the body and tail critical to this saving. Flap-gliding is thought to be less costly than continuous flapping during flight at most speeds. Some species are known to shift from flap-gliding at slow speeds to flap-bounding at fast speeds, but there is an upper size limit for the ability to bound (∼0.3 kg) and small birds with rounded wings do not use intermittent glides.

  14. Hovering and intermittent flight in birds

    Energy Technology Data Exchange (ETDEWEB)

    Tobalske, Bret W, E-mail: bret.tobalske@mso.umt.ed [Field Research Station at Fort Missoula, Division of Biological Sciences, University of Montana, Missoula, MT 59812 (United States)

    2010-12-15

    Two styles of bird locomotion, hovering and intermittent flight, have great potential to inform future development of autonomous flying vehicles. Hummingbirds are the smallest flying vertebrates, and they are the only birds that can sustain hovering. Their ability to hover is due to their small size, high wingbeat frequency, relatively large margin of mass-specific power available for flight and a suite of anatomical features that include proportionally massive major flight muscles (pectoralis and supracoracoideus) and wing anatomy that enables them to leave their wings extended yet turned over (supinated) during upstroke so that they can generate lift to support their weight. Hummingbirds generate three times more lift during downstroke compared with upstroke, with the disparity due to wing twist during upstroke. Much like insects, hummingbirds exploit unsteady mechanisms during hovering including delayed stall during wing translation that is manifest as a leading-edge vortex (LEV) on the wing and rotational circulation at the end of each half stroke. Intermittent flight is common in small- and medium-sized birds and consists of pauses during which the wings are flexed (bound) or extended (glide). Flap-bounding appears to be an energy-saving style when flying relatively fast, with the production of lift by the body and tail critical to this saving. Flap-gliding is thought to be less costly than continuous flapping during flight at most speeds. Some species are known to shift from flap-gliding at slow speeds to flap-bounding at fast speeds, but there is an upper size limit for the ability to bound ({approx}0.3 kg) and small birds with rounded wings do not use intermittent glides.

  15. Power by waste heat recovery from low temperature industrial flue gas by Organic Flash Cycle (OFC) and transcritical-CO_2 power cycle: A comparative study through combined thermodynamic and economic analysis

    International Nuclear Information System (INIS)

    Mondal, Subha; De, Sudipta

    2017-01-01

    Both Organic flash cycle and transcritical CO_2 power cycle (T-CO_2 power cycle) allow cooling of hot flue gas stream to an appreciably lower temperature due to the absence of pinch limitation. In the present study, a combined thermodynamic and economic comparison is conducted between a T-CO_2 power cycle and Organic flash cycles using R-245fa and R600 as the working fluids. It is observed that work output per kg of flue gas flow rate is slightly higher for the T-CO_2 power cycle if the flue gas is allowed to cool to the corresponding lowest possible temperature in the Heat Recovery Unit (HRU). It is also observed that with maximum possible cooling of flue gas, minimum bare module costs (BMCs) for each kW power output of OFCs are somewhat higher compared to that of T-CO_2 power cycle. Minimum BMCs for each kW output of OFCs can be reduced substantially by increasing terminal temperature difference at the low temperature end of the HRU. However, the increasing terminal temperature difference at the low temperature end of the HRU is having negligible effect on BMC ($/kW) of T-CO_2 power cycle. - Highlights: • Combined thermodynamic and economic analysis done for T-CO_2 power cycle and OFC. • With highest heat recovery, T-CO_2 cycle produces slightly higher work output/kg of flue gas. • With highest heat recovery, minimum bare module costs in $/kW is slightly higher for OFCs. • Work outputs/kg of flue gas of all cycles are almost equal for these minimum BMCs. • BMCs in $/kW for OFCs sharply decrease with larger flue gas exit temperature.

  16. Scaling the Thrust Production and Energetics of Inviscid Intermittent Swimming

    Science.gov (United States)

    Akoz, Emre; Moored, Keith

    2015-11-01

    Many fish have adopted an intermittent swimming gait sometimes referred as a burst-and-coast behavior. By using this gait, fish have been estimated at reducing their energetic cost of swimming by about 50%. Lighthill proposed that the skin friction drag of an undulating body can be around 400% greater than a rigidly-held coasting body, which may explain the energetic savings of intermittent swimming. Recent studies have confirmed the increase in skin friction drag over an undulating body, however, the increase is on the order of 20-70%. This more modest gain in skin friction drag is not sufficient to lead to the observed energy savings. Motivated by these observations, we investigate the inviscid mechanisms behind intermittent swimming for parameters typical of biology. We see that there is an energy savings at a fixed swimming speed for intermittent swimming as compared to continuous swimming. Then we consider three questions: What is the nature of the inviscid mechanism that leads to the observed energy savings, how do the forces and energetics of intermittent swimming scale with the swimming parameters, and what are the limitations to the benefit? Supported by the Office of Naval Research under Program Director Dr. Bob Brizzola, MURI grant number N00014-14-1-0533.

  17. TRANSIENT GALACTIC COSMIC-RAY MODULATION DURING SOLAR CYCLE 24: A COMPARATIVE STUDY OF TWO PROMINENT FORBUSH DECREASE EVENTS

    International Nuclear Information System (INIS)

    Zhao, L.-L.; Zhang, H.

    2016-01-01

    Forbush decrease (FD) events are of great interest for transient galactic cosmic-ray (GCR) modulation study. In this study, we perform comparative analysis of two prominent Forbush events during cycle 24, occurring on 2012 March 8 (Event 1) and 2015 June 22 (Event 2), utilizing the measurements from the worldwide neutron monitor (NM) network. Despite their comparable magnitudes, the two Forbush events are distinctly different in terms of evolving GCR energy spectrum and energy dependence of the recovery time. The recovery time of Event 1 is strongly dependent on the median energy, compared to the nearly constant recovery time of Event 2 over the studied energy range. Additionally, while the evolutions of the energy spectra during the two FD events exhibit similar variation patterns, the spectrum of Event 2 is significantly harder, especially at the time of deepest depression. These difference are essentially related to their associated solar wind disturbances. Event 1 is associated with a complicated shock-associated interplanetary coronal mass ejection (ICME) disturbance with large radial extent, probably formed by the merging of multiple shocks and transient flows, and which delivered a glancing blow to Earth. Conversely, Event 2 is accompanied by a relatively simple halo ICME with small radial extent that hit Earth more head-on.

  18. TRANSIENT GALACTIC COSMIC-RAY MODULATION DURING SOLAR CYCLE 24: A COMPARATIVE STUDY OF TWO PROMINENT FORBUSH DECREASE EVENTS

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, L.-L.; Zhang, H., E-mail: zhaolingling@ucas.edu.cn [Key Laboratory of Computational Geodynamics, University of Chinese Academy of Sciences, Beijing 100049 (China)

    2016-08-10

    Forbush decrease (FD) events are of great interest for transient galactic cosmic-ray (GCR) modulation study. In this study, we perform comparative analysis of two prominent Forbush events during cycle 24, occurring on 2012 March 8 (Event 1) and 2015 June 22 (Event 2), utilizing the measurements from the worldwide neutron monitor (NM) network. Despite their comparable magnitudes, the two Forbush events are distinctly different in terms of evolving GCR energy spectrum and energy dependence of the recovery time. The recovery time of Event 1 is strongly dependent on the median energy, compared to the nearly constant recovery time of Event 2 over the studied energy range. Additionally, while the evolutions of the energy spectra during the two FD events exhibit similar variation patterns, the spectrum of Event 2 is significantly harder, especially at the time of deepest depression. These difference are essentially related to their associated solar wind disturbances. Event 1 is associated with a complicated shock-associated interplanetary coronal mass ejection (ICME) disturbance with large radial extent, probably formed by the merging of multiple shocks and transient flows, and which delivered a glancing blow to Earth. Conversely, Event 2 is accompanied by a relatively simple halo ICME with small radial extent that hit Earth more head-on.

  19. Two cycles of plasma rich in growth factors (PRGF-Endoret) intra-articular injections improve stiffness and activities of daily living but not pain compared to one cycle on patients with symptomatic knee osteoarthritis.

    Science.gov (United States)

    Vaquerizo, Víctor; Padilla, Sabino; Aguirre, José Javier; Begoña, Leire; Orive, Gorka; Anitua, Eduardo

    2017-05-19

    To assess the clinical efficacy and safety of a treatment based on one cycle versus two cycles of intra-articular injections of plasma rich in growth factors (PRGF-Endoret) on patients with knee osteoarthritis (OA). Ninety patients with knee OA were included and evaluated. A total of 48 patients received one cycle (OC group) (3 injections on a weekly basis), while 42 patients received two cycles of PRGF-Endoret (TC group) spaced 6 months between them. Patients were evaluated with LEQUESNE and WOMAC scores before treatment and after 48 weeks. Safety assessment was also performed. A significant reduction of all assessed outcome measures was shown for both groups at 48 weeks compared with baseline values (P PRGF did not show a significantly higher pain reduction compared with one cycle treatment. However, two cycles of PRGF showed a significant improvement in WOMAC stiffness, LEQUESNE MCD, LEQUESNE ADV and LEQUESNE global subscales. Therefore, patients treated with two cycles present an improvement in quality of life. II.

  20. Life cycle cost analysis of wind power considering stochastic uncertainties

    International Nuclear Information System (INIS)

    Li, Chiao-Ting; Peng, Huei; Sun, Jing

    2014-01-01

    This paper presents a long-term cost analysis of wind power and compares its competitiveness to non-renewable generating technologies. The analysis considers several important attributes related to wind intermittency that are sometimes ignored in traditional generation planning or LCOE (levelized cost of energy) studies, including the need for more nameplate capacity due to intermittency, hourly fluctuations in wind outputs and cost for reserves. The competitiveness of wind power is assessed by evaluating four scenarios: 1) adding natural gas generating capacity to the power grid; 2) adding coal generating capacity to the power grid; 3) adding wind capacity to the power grid; and, 4) adding wind capacity and energy storage to the power grid where an energy storage device is used to cover wind intermittency. A case study in the state of Michigan is presented to demonstrate the use of the proposed methodology, in which a time horizon from 2010 to 2040 is considered. The results show that wind energy will still be more expensive than natural gas power plants in the next three decades, but will be cheaper than coal capacities if wind intermittency is mitigated. Furthermore, if the costs of carbon emissions and environmental externalities are considered, wind generation will be a competitive option for grid capacity expansion. - Highlights: • The competitiveness of wind power is analyzed via life cycle cost analysis. • Wind intermittency and reserve costs are explicitly considered in the analysis. • Results show that wind is still more expensive than natural gas power plants. • Wind can be cheaper than coal capacities if wind intermittency is mitigated. • Wind will be competitive if costs of carbon emissions are considered

  1. Environmental implications of United States coal exports: a comparative life cycle assessment of future power system scenarios.

    Science.gov (United States)

    Bohnengel, Barrett; Patiño-Echeverri, Dalia; Bergerson, Joule

    2014-08-19

    Stricter emissions requirements on coal-fired power plants together with low natural gas prices have contributed to a recent decline in the use of coal for electricity generation in the United States. Faced with a shrinking domestic market, many coal companies are taking advantage of a growing coal export market. As a result, U.S. coal exports hit an all-time high in 2012, fueled largely by demand in Asia. This paper presents a comparative life cycle assessment of two scenarios: a baseline scenario in which coal continues to be burned domestically for power generation, and an export scenario in which coal is exported to Asia. For the coal export scenario we focus on the Morrow Pacific export project being planned in Oregon by Ambre Energy that would ship 8.8 million tons of Powder River Basin (PRB) coal annually to Asian markets via rail, river barge, and ocean vessel. Air emissions (SOx, NOx, PM10 and CO2e) results assuming that the exported coal is burned for electricity generation in South Korea are compared to those of a business as usual case in which Oregon and Washington's coal plants, Boardman and Centralia, are retrofitted to comply with EPA emissions standards and continue their coal consumption. Findings show that although the environmental impacts of shipping PRB coal to Asia are significant, the combination of superior energy efficiency among newer South Korean coal-fired power plants and lower emissions from U.S. replacement of coal with natural gas could lead to a greenhouse gas reduction of 21% in the case that imported PRB coal replaces other coal sources in this Asian country. If instead PRB coal were to replace natural gas or nuclear generation in South Korea, greenhouse gas emissions per unit of electricity generated would increase. Results are similar for other air emissions such as SOx, NOx and PM. This study provides a framework for comparing energy export scenarios and highlights the importance of complete life cycle assessment in

  2. Pollution by air filters: Continuous vs intermittent air flow

    NARCIS (Netherlands)

    Cox, C.W.J.; Bluyssen, P.M.

    2000-01-01

    Within the framework of the EU research project Airless, a long-term experiment of 28 weeks was carried out to investigate the influence of intermittent airflow compared to continuous airflow on the pollution effect of glass fibre filters (F7). No statistical relevant differences between odour

  3. Peripheral arterial disease and intermittent claudication: Efficacy of ...

    African Journals Online (AJOL)

    Objective. To compare the effect of two training programmes and advice to exercise at home on physiological adaptations in patients with peripheral arterial disease (PAD). Design. 30 patients with a typical history of PAD and intermittent claudication were randomised to either an upper body strength training programme ...

  4. Intermittent Fasting Modulation of the Diabetic Syndrome in Streptozotocin-Injected Rats

    Directory of Open Access Journals (Sweden)

    Louiza Belkacemi

    2012-01-01

    Full Text Available This study investigates the effects of intermittent overnight fasting in streptozotocin-induced diabetic rats (STZ rats. Over 30 days, groups of 5-6 control or STZ rats were allowed free food access, starved overnight, or exposed to a restricted food supply comparable to that ingested by the intermittently fasting animals. Intermittent fasting improved glucose tolerance, increased plasma insulin, and lowered Homeostatis Model Assessment index. Caloric restriction failed to cause such beneficial effects. The β-cell mass, as well as individual β-cell and islet area, was higher in intermittently fasting than in nonfasting STZ rats, whilst the percentage of apoptotic β-cells appeared lower in the former than latter STZ rats. In the calorie-restricted STZ rats, comparable findings were restricted to individual islet area and percentage of apoptotic cells. Hence, it is proposed that intermittent fasting could represent a possible approach to prevent or minimize disturbances of glucose homeostasis in human subjects.

  5. Chronic intermittent hypoxia predisposes to liver injury.

    Science.gov (United States)

    Savransky, Vladimir; Nanayakkara, Ashika; Vivero, Angelica; Li, Jianguo; Bevans, Shannon; Smith, Philip L; Torbenson, Michael S; Polotsky, Vsevolod Y

    2007-04-01

    Obstructive sleep apnea (OSA) is characterized by chronic intermittent hypoxia (CIH). OSA is associated with nonalcoholic steatohepatitis (NASH) in obese subjects. The aim of this study was to investigate the effects of CIH on the liver in the absence of obesity. Lean C57BL/6J mice (n = 15) on a regular chow diet were exposed to CIH for 12 weeks and compared with pair-fed mice exposed to intermittent air (IA, n = 15). CIH caused liver injury with an increase in serum ALT (224 +/- 39 U/l versus 118 +/- 22 U/l in the IA group, P fasting serum insulin levels, and mild elevation of fasting serum total cholesterol and triglycerides (TG). Liver TG content was unchanged, whereas cholesterol content was decreased. Histology showed swelling of hepatocytes, no evidence of hepatic steatosis, and marked accumulation of glycogen in hepatocytes. CIH led to lipid peroxidation of liver tissue with a malondialdehyde (MDA)/free fatty acids (FFA) ratio of 0.54 +/- 0.07 mmol/mol versus 0.30 +/- 0.01 mmol/mol in control animals (P obesity, CIH leads to mild liver injury via oxidative stress and excessive glycogen accumulation in hepatocytes and sensitizes the liver to a second insult, whereas NASH does not develop.

  6. Intermittent oral iron supplementation during pregnancy (Review)

    Science.gov (United States)

    Peña-Rosas, Juan Pablo; De-Regil, Luz Maria; Dowswell, Therese; Viteri, Fernando E

    2014-01-01

    Background Anaemia is a frequent condition during pregnancy, particularly among women from developing countries who have insufficient iron intake to meet increased iron needs of both the mother and the fetus. Traditionally, gestational anaemia has been prevented with the provision of daily iron supplements throughout pregnancy, but adherence to this regimen due to side effects, interrupted supply of the supplements, and concerns about safety among women with an adequate iron intake, have limited the use of this intervention. Intermittent (i.e. one, two or three times a week on non-consecutive days) supplementation with iron alone or in combination with folic acid or other vitamins and minerals has recently been proposed as an alternative to daily supplementation. Objectives To assess the benefits and harms of intermittent supplementation with iron alone or in combination with folic acid or other vitamins and minerals to pregnant women on neonatal and pregnancy outcomes. Search methods We searched the Cochrane Pregnancy and Childbirth Group’s Trials Register (23 March 2012). We also searched the WHO International Clinical Trials Registry Platform (ICTRP) for ongoing studies and contacted relevant organisations for the identification of ongoing and unpublished studies (23 March 2012). Selection criteria Randomised or quasi-randomised trials. Data collection and analysis We assessed the methodological quality of trials using standard Cochrane criteria. Two review authors independently assessed trial eligibility, extracted data and conducted checks for accuracy. Main results This review includes 21 trials from 13 different countries, but only 18 trials (with 4072 women) reported on our outcomes of interest and contributed data to the review. All of these studies compared daily versus intermittent iron supplementation. Three studies provided iron alone, 12 iron+folic acid and three more iron plus multiple vitamins and minerals. Their methodological quality was mixed

  7. Effects of Intermittent Neck Cooling During Repeated Bouts of High-Intensity Exercise

    Directory of Open Access Journals (Sweden)

    Andrew J. Galpin

    2016-06-01

    Full Text Available The purpose of this investigation was to determine the influence of intermittent neck cooling during exercise bouts designed to mimic combat sport competitions. Participants (n = 13, age = 25.3 ± 5.0 year height = 176.9 ± 7.5 cm, mass = 79.3 ± 9.0 kg, body fat = 11.8% ± 3.1% performed three trials on a cycle ergometer. Each trial consisted of two, 5-min high-intensity exercise (HEX intervals (HEX1 and HEX2—20 s at 50% peak power, followed by 15 s of rest, and a time to exhaustion (TTE test. One-minute rest intervals were given between each round (RI1 and RI2, during which researchers treated the participant’s posterior neck with either (1 wet-ice (ICE; (2 menthol spray (SPRAY; or (3 no treatment (CON. Neck (TNECK and chest (TCHEST skin temperatures were significantly lower following RI1 with ICE (vs. SPRAY. Thermal sensation decreased with ICE compared to CON following RI1, RI2, TTE, and a 2-min recovery. Rating of perceived exertion was also lower with ICE following HEX2 (vs. CON and after RI2 (vs. SPRAY. Treatment did not influence TTE (68.9 ± 18.9s. The ability of intermittent ICE to attenuate neck and chest skin temperature rises during the initial HEX stages likely explains why participants felt cooler and less exerted during equivalent HEX bouts. These data suggest intermittent ICE improves perceptual stress during short, repeated bouts of vigorous exercise.

  8. Environmental heat stress, hyperammonemia and nucleotide metabolism during intermittent exercise

    DEFF Research Database (Denmark)

    Mohr, Magni; Rasmussen, Peter; Drust, Barry

    2006-01-01

    ) followed by five 15 s all-out sprints. Control trials were conducted in a 20°C environment while heat stress trials were performed at an ambient temperature of 40°C. Muscle biopsies and venous blood samples were obtained at rest, after 40 min of exercise and following the maximal sprints. Following......Abstract  This study investigated the influence of environmental heat stress on ammonia (NH3) accumulation in relation to nucleotide metabolism and fatigue during intermittent exercise. Eight males performed 40 min of intermittent exercise (15 s at 306±22 W alternating with 15 s of unloaded cycling...... exercise with heat stress, the core and muscle temperatures peaked at 39.5±0.2 and 40.2±0.2°C to be ~ 1°C higher (Pheat stress trial (P

  9. Considering Intermittent Dormancy in an Advanced Life Support Systems Architecture

    Science.gov (United States)

    Sargusingh, Miriam J.; Perry, Jay L.

    2017-01-01

    Many advanced human space exploration missions being considered by the National Aeronautics and Space Administration (NASA) include concepts in which in-space systems cycle between inhabited and uninhabited states. Managing the life support system (LSS) may be particularly challenged during these periods of intermittent dormancy. A study to identify LSS management challenges and considerations relating to dormancy is described. The study seeks to define concepts suitable for addressing intermittent dormancy states and to evaluate whether the reference LSS architectures being considered by the Advanced Exploration Systems (AES) Life Support Systems Project (LSSP) are sufficient to support this operational state. The primary focus of the study is the mission concept considered to be the most challenging-a crewed Mars mission with an extensive surface stay. Results from this study are presented and discussed.

  10. Hierarchy compensation of non-homogeneous intermittent atmospheric turbulence

    Science.gov (United States)

    Redondo, Jose M.; Mahjoub, Otman B.; Cantalapiedra, Inma R.

    2010-05-01

    In this work a study both the internal turbulence energy cascade intermittency evaluated from wind speed series in the atmospheric boundary layer, as well as the role of external or forcing intermittency based on the flatness (Vindel et al 2008)is carried out. The degree of intermittency in the stratified ABL flow (Cuxart et al. 2000) can be studied as the deviation, from the linear form, of the absolute scaling exponents of the structure functions as well as generalizing for non-isotropic and non-homogeneous turbulence, even in non-inertial ranges (in the Kolmogorov-Kraichnan sense) where the scaling exponents are not constant. The degree of intermittency, evaluated in the non-local quasi-inertial range, is explained from the variation with scale of the energy transfer as well as the dissipation. The scale to scale transfer and the structure function scaling exponents are calculated and from these the intermittency parametres. The turbulent diffusivity could also be estimated and compared with Richardson's law. Some two point correlations and time lag calculations are used to investigate the time and spatial integral length scales obtained from both Lagrangian and Eulerian correlations and functions, and we compare these results with both theoretical and laboratory data. We develop a theoretical description of how to measure the different levels of intermittency following (Mahjoub et al. 1998, 2000) and the role of locality in higher order exponents of structure function analysis. Vindel J.M., Yague C. and Redondo J.M. (2008) Structure function analysis and intermittency in the ABL. Nonlin. Processes Geophys., 15, 915-929. Cuxart J, Yague C, Morales G, Terradellas E, Orbe J, Calvo J, Fernández A, Soler M R, Infante C, Buenestado P, Espinalt A, Joergensen H E, Rees J M, Vilá J, Redondo J M, Cantalapiedra R and Conangla L (2000): Stable atmospheric boundary-layer experiment in Spain (Sables 98): a report, Boundary-Layer Meteorology 96, 337-370 Mahjoub O

  11. Intermittent fasting interventions for the treatment of overweight and obesity in adults aged 18 years and over: a systematic review and meta-analysis

    OpenAIRE

    Harris, Leanne; Hamilton, Sharon; Azevedo, Liane B.; Olajide, Joan; De Brun, Caroline; Waller, Gillian; Whittaker, Vicki; Sharp, Tracey; Lean, Mike; Hankey, Catherine; Ells, Louisa

    2018-01-01

    Objective:\\ud To examine the effectiveness of intermittent energy restriction in the treatment for overweight and obesity in adults, when compared to usual care treatment or no treatment.\\ud \\ud Introduction:\\ud Intermittent energy restriction encompasses dietary approaches including intermittent fasting, alternate day fasting, and fasting for two days per week. Despite the recent popularity of intermittent energy restriction and associated weight loss claims, the supporting evidence base is ...

  12. Performance evaluation of an irreversible Miller cycle comparing FTT (finite-time thermodynamics) analysis and ANN (artificial neural network) prediction

    International Nuclear Information System (INIS)

    Mousapour, Ashkan; Hajipour, Alireza; Rashidi, Mohammad Mehdi; Freidoonimehr, Navid

    2016-01-01

    In this paper, the first and second-laws efficiencies are applied to performance analysis of an irreversible Miller cycle. In the irreversible cycle, the linear relation between the specific heat of the working fluid and its temperature, the internal irreversibility described using the compression and expansion efficiencies, the friction loss computed according to the mean velocity of the piston and the heat-transfer loss are considered. The effects of various design parameters, such as the minimum and maximum temperatures of the working fluid and the compression ratio on the power output and the first and second-laws efficiencies of the cycle are discussed. In the following, a procedure named ANN is used for predicting the thermal efficiency values versus the compression ratio, and the minimum and maximum temperatures of the Miller cycle. Nowadays, Miller cycle is widely used in the automotive industry and the obtained results of this study will provide some significant theoretical grounds for the design optimization of the Miller cycle. - Highlights: • The performance of an irreversible Miller cycle is investigated using FFT. • The effects of design parameters on the performance of the cycle are investigated. • ANN is applied to predict the thermal efficiency and the power output values. • There is an excellent correlation between FTT and ANN data. • ANN can be applied to predict data where FTT analysis has not been performed.

  13. Comparative cradle-to-grave life cycle assessment of biogas production from marine algae and cattle manure biorefineries.

    Science.gov (United States)

    Giwa, Adewale

    2017-11-01

    The environmental impacts resulting from the cradle-to-grave life cycles of Enteromorpha prolifera macroalgae and cattle manure biorefineries are assessed and compared. Sensitivity analysis is carried out to evaluate the response of the impacts to changes in biogas application by using Simapro 7.3.3. Three scenarios are considered in the biorefineries. In the first and second scenarios, the biogas produced is considered to be used for electricity production and transportation, respectively. In the third scenario, the biogas is considered to be recycled back to the systems. Process energy requirements and transportation of inputs contribute the largest share of the overall impacts. The cattle manure biorefinery is slightly more eco-friendly than the macroalgae biorefinery in Scenarios 1 and 2 because it requires more eco-friendly inputs. However, the macroalgae biorefinery becomes more eco-friendly than the cattle manure biorefinery in Scenario 3 because macroalgae require less energy and water for biogas production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Performance characteristics of seven bilevel mechanical ventilators in pressure-support mode with different cycling criteria: a comparative bench study.

    Science.gov (United States)

    Chen, Yuqing; Cheng, Kewen; Zhou, Xin

    2015-01-26

    Pressure support ventilation from a bilevel device is a standard technique for non-invasive home ventilation. A bench study was designed to compare the performance and patient-ventilator synchronization of 7 bilevel ventilators, in the presence of system leaks. Ventilators were connected to a Hans Rudolph Series 1101 lung simulator (compliance, 50 mL/cmH2O; expiratory resistance, 20 cmH2O/L/s; respiratory rate, 15 breaths/min; inspiratory time, 1.0 s). All ventilators were set at 15 cmH2O pressure support and 5 cmH2O positive end-expiratory pressure. Tests were conducted at 2 system leaks (12-15 and 25-28 L/min). The performance characteristics and patient-ventilator asynchrony were assessed, including flow, airway pressure, time, and workload. The Breas Vivo30 could not synchronize with the simulator (frequent auto-triggering) at a leak of 25-28 L/min, but provided stable assisted ventilation when the leak was 12-15 L/min. Missed efforts and back-up ventilation occurred for the Weinmann VENTImotion and Airox Smartair Plus, requiring adjustment of trigger effort. All ventilators had a short trigger delay time (ventilators, possibly due to software algorithm differences. Adjusting the cycling criteria settings can alter the shape of the inspiratory phase and peak expiratory flow, and improve patient-ventilator synchrony.

  15. Intermittent episodes of bright light suppress myopia in the chicken more than continuous bright light.

    Science.gov (United States)

    Lan, Weizhong; Feldkaemper, Marita; Schaeffel, Frank

    2014-01-01

    Bright light has been shown a powerful inhibitor of myopia development in animal models. We studied which temporal patterns of bright light are the most potent in suppressing deprivation myopia in chickens. Eight-day-old chickens wore diffusers over one eye to induce deprivation myopia. A reference group (n = 8) was kept under office-like illuminance (500 lux) at a 10:14 light:dark cycle. Episodes of bright light (15 000 lux) were super-imposed on this background as follows. Paradigm I: exposure to constant bright light for either 1 hour (n = 5), 2 hours (n = 5), 5 hours (n = 4) or 10 hours (n = 4). Paradigm II: exposure to repeated cycles of bright light with 50% duty cycle and either 60 minutes (n = 7), 30 minutes (n = 8), 15 minutes (n = 6), 7 minutes (n = 7) or 1 minute (n = 7) periods, provided for 10 hours. Refraction and axial length were measured prior to and immediately after the 5-day experiment. Relative changes were analyzed by paired t-tests, and differences among groups were tested by one-way ANOVA. Compared with the reference group, exposure to continuous bright light for 1 or 2 hours every day had no significant protective effect against deprivation myopia. Inhibition of myopia became significant after 5 hours of bright light exposure but extending the duration to 10 hours did not offer an additional benefit. In comparison, repeated cycles of 1:1 or 7:7 minutes of bright light enhanced the protective effect against myopia and could fully suppress its development. The protective effect of bright light depends on the exposure duration and, to the intermittent form, the frequency cycle. Compared to the saturation effect of continuous bright light, low frequency cycles of bright light (1:1 min) provided the strongest inhibition effect. However, our quantitative results probably might not be directly translated into humans, but rather need further amendments in clinical studies.

  16. Comparative evaluation of a natural gas expansion plant integrated with an IC engine and an organic Rankine cycle

    International Nuclear Information System (INIS)

    Kostowski, Wojciech J.; Usón, Sergio

    2013-01-01

    Highlights: • Comparison of natural gas expansion systems integrated with gas boiler, ICE and ORC. • Expansion systems replace the throttling process in pressure regulating stations. • 5 System performance indicators based on the 1st and 2nd law are defined. • Exergy efficiency was calculated from the fuel-product approach. • ORC system yields highest exergy efficiency 52.6% and performance ratio of 0.771. - Abstract: The aim of the paper is to propose and evaluate an innovative exergy recovery system for natural gas expansion, based on the integration of an internal combustion engine (ICE) and an organic Rankine cycle (ORC), and to compare it with other alternatives. Natural gas expansion plants are a substantial improvement to the conventional gas pressure reduction stations, based on the throttling process, since the available physical exergy of pressurized gas is converted into mechanical energy by means of an expansion machine (turbine or piston expander) instead of being lost in the throttling process. However, due to the hydrate formation problem the gas has to be pre-heated prior to the expansion, which diminishes the system performance. An efficient method for performing this pre-heating is by the proposed system that comprises an ICE and an ORC: Pre-heating of natural gas is carried out partially directly by the co-generation module, via the engine cooling cycle, and partially indirectly, by means of the engine exhaust gases, which supply heat for the ORC, while the ORC condenser is connected with the lowest stage of natural gas pre-heating. Other alternatives are the use of an ICE without ORC, the use of a boiler, and even expansion in a throttling valve. The paper evaluates the performance of the aforementioned four configurations by means of both energy and exergy analysis. Several alternative performance indicators have been defined, calculated and discussed. Sources of irreversibilities have been identified by means of exergy analysis

  17. Adequacy in dialysis: intermittent versus continuous therapies.

    Science.gov (United States)

    Misra, M; Nolph, K D

    2000-01-01

    relationship between outcome and dialysis dose needs to be better defined. Data relating adequacy of dialysis to outcome in a pediatric population is not available. In dialysis therapy, the Risk/Dose (R/D) function does not bear a linear relationship. This together with a lack of proof equating peritoneal to renal clearance lends some uncertainty to the validity of the recommendation that there is a linear and constant decrease in RR for std (Kt/V) [equivalent standardized Kt/V calculated from average predialysis BUN for any frequency and/or combination of intermittent and continuous dialysis ref] up to 2.3 as reported in the CANUSA study. Due to the complex nature of this problem it may be prudent to undertake a multi-center trial with std (Kt/V) prospectively randomized to either 2.0 or 2.4. This would provide a reliable database to evaluate the R/D function over this critical range of normalized peritoneal urea clearance. Likewise in PD, the postulated linearity between dialysis dose and outcome needs to be studied in a prospective randomized manner. The amount of dialysis dose required for malnourished patients, diabetic and pediatric patients needs to be better defined. The role of aggressive dialysis in reversing malnutrition needs to be studied and studies need to be done to identify the most scientific use of V in malnourished patients. Justification of a healthy start/incremental dialysis based on outcome measures needs to be established and it's cost effectiveness validated by clinical trials. Again, a prospective randomized controlled trial comparing incremental dialysis with dietary protein restriction in patients with GFR < or = 10.5 ml/min/1.73 m2 with properly defined outcome measures like morbidity, mortality, decline of GFR and quality of life needs to be conducted. Comparisons of incremental hemodialysis and incremental peritoneal dialysis need to be made especially with regard to technique survival and preservation of residual renal function (RRF). (ABSTR

  18. Subsurface Controls on Stream Intermittency in a Semi-Arid Landscape

    Science.gov (United States)

    Dohman, J.; Godsey, S.; Thackray, G. D.; Hale, R. L.; Wright, K.; Martinez, D.

    2017-12-01

    Intermittent streams currently constitute 30% to greater than 50% of the global river network. In addition, the number of intermittent streams is expected to increase due to changes in land use and climate. These streams provide important ecosystem services, such as water for irrigation, increased biodiversity, and high rates of nutrient cycling. Many hydrological studies have focused on mapping current intermittent flow regimes or evaluating long-term flow records, but very few have investigated the underlying causes of stream intermittency. The disconnection and reconnection of surface flow reflects the capacity of the subsurface to accommodate flow, so characterizing subsurface flow is key to understanding stream drying. We assess how subsurface flow paths control local surface flows during low-flow periods, including intermittency. Water table dynamics were monitored in an intermittent reach of Gibson Jack Creek in southeastern Idaho. Four transects were delineated with a groundwater well located in the hillslope, riparian zone, and in the stream, for a total of 12 groundwater wells. The presence or absence of surface flow was determined by frequent visual observations as well as in situ loggers every 30m along the 200m study reach. The rate of surface water drying was measured in conjunction with temperature, precipitation, subsurface hydraulic conductivity, hillslope-riparian-stream connectivity and subsurface travel time. Initial results during an unusually wet year suggest different responses in reaches that were previously observed to occasionally cease flowing. Flows in the intermittent reaches had less coherent and lower amplitude diel variations during base flow periods than reaches that had never been observed to dry out. Our findings will help contribute to our understanding of mechanisms driving expansion and contraction cycles in intermittent streams, increase our ability to predict how land use and climate change will affect flow regimes, and

  19. The effect of intermittent lighting on metabolizable energy intake and heat production of male broilers.

    Science.gov (United States)

    Ohtani, S; Leeson, S

    2000-02-01

    Experiments were conducted to compare the effects of an intermittent lighting (IL) schedule with repeated cycles of 1 h light and 2 h darkness with a continuous lighting (CL) schedule on the performance, ME intake, and heat production of male broiler chickens. Body weight gain and feed intake were temporarily reduced after the changing from CL to IL; however, they were significantly higher in IL vs CL chickens during the subsequent period of 3 to 6 wk of age. The IL chickens exhibited a higher ME intake at 6 and 8 wk of age than did CL chickens. Total heat production in IL chickens was higher than for CL chickens, although heat production during the dark period was less than that during the light period for IL chickens. The higher feed intake observed in IL chickens appears to explain the superior body weight gain in IL broilers in simple terms.

  20. Dynamic water management of polymer electrolyte membrane fuel cells using intermittent RH control

    KAUST Repository

    Hussaini, I.S.

    2010-06-01

    A novel method of water management of polymer electrolyte membrane (PEM) fuel cells using intermittent humidification is presented in this study. The goal is to maintain the membrane close to full humidification, while eliminating channel flooding. The entire cycle is divided into four stages: saturation and de-saturation of the gas diffusion layer followed by de-hydration and hydration of membrane. By controlling the duration of dry and humid flows, it is shown that the cell voltage can be maintained within a narrow band. The technique is applied on experimental test cells using both plain and hydrophobic materials for the gas diffusion layer and an improvement in performance as compared to steady humidification is demonstrated. Duration of dry and humid flows is determined experimentally for several operating conditions. © 2010 Elsevier B.V. All rights reserved.

  1. An intermittency route to global instability in low-density jets

    Science.gov (United States)

    Murugesan, Meenatchidevi; Zhu, Yuanhang; Li, Larry K. B.

    2017-11-01

    Above a critical Reynolds number (Re), a low-density jet can become globally unstable, transitioning from a steady state (i.e. a fixed point) to a self-excited oscillatory state (i.e. a limit cycle) via a Hopf bifurcation. In this experimental study, we show that this transition can sometimes involve intermittency. When Re is just slightly above the critical point, intermittent bursts of high-amplitude periodic oscillations emerge amidst a background of low-amplitude aperiodic fluctuations. As Re increases further, these intermittent bursts persist longer in time until they dominate the overall dynamics, causing the jet to transition fully to a periodic limit cycle. We identify this as Type-II Pomeau-Manneville intermittency by quantifying the statistical distribution of the duration of the aperiodic fluctuations at the onset of intermittency. This study shows that the transition to global instability in low-density jets is not always abrupt but can involve an intermediate state with characteristics of both the initial fixed point and the final limit cycle. This work was supported by the Research Grants Council of Hong Kong (Project No. 16235716 and 26202815).

  2. Postural reconfiguration and cycle-to-cycle variability in patients with work-related musculoskeletal disorders compared to healthy controls and in relation to pain emerging during a repetitive movement task.

    Science.gov (United States)

    Longo, Alessia; Meulenbroek, Ruud; Haid, Thomas; Federolf, Peter

    2018-05-01

    Movement variability in sustained repetitive tasks is an important factor in the context of work-related musculoskeletal disorders. While a popular hypothesis suggests that movement variability can prevent overuse injuries, pain evolving during task execution may also cause variability. The aim of the current study was to investigate, first, differences in movement behavior between volunteers with and without work-related pain and, second, the influence of emerging pain on movement variability. Upper-body 3D kinematics were collected as 22 subjects with musculoskeletal disorders and 19 healthy volunteers performed a bimanual repetitive tapping task with a self-chosen and a given rhythm. Three subgroups were formed within the patient group according to the level of pain the participants experienced during the task. Principal component analysis was applied to 30 joint angle coordinates to characterize in a combined analysis the movement variability associated with reconfigurations of the volunteers' postures and the cycle-to-cycle variability that occurred during the execution of the task. Patients with no task-related pain showed lower cycle-to-cycle variability compared to healthy controls. Findings also indicated an increase in movement variability as pain emerged, manifesting both as frequent postural changes and large cycle-to-cycle variability. The findings suggested a relationship between work-related musculoskeletal disorders and movement variability but further investigation is needed on this issue. Additionally, the findings provided clear evidence that pain increased motor variability. Postural reconfigurations and cycle-to-cycle variability should be considered jointly when investigating movement variability and musculoskeletal disorders. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Compensatory mechanisms activated with intermittent energy restriction

    DEFF Research Database (Denmark)

    Coutinho, Sílvia Ribeiro; Halset, Eline Holli; Gåsbakk, Sigrid

    2018-01-01

    Background & aims: Strong compensatory responses, with reduced resting metabolic rate (RMR), increased exercise efficiency (ExEff) and appetite, are activated when weight loss (WL) is achieved with continuous energy restriction (CER), which try to restore energy balance. Intermittent energy...... restriction (IER), where short spells of energy restriction are interspaced by periods of habitual energy intake, may offer some protection in minimizing those responses. We aimed to compare the effect of IER versus CER on body composition and the compensatory responses induced by WL. Methods: 35 adults (age......: 39 ± 9 y) with obesity (BMI: 36 ± 4 kg/m2) were randomized to lose a similar weight with an IER (N = 18) or a CER (N = 17) diet over a 12 week period. Macronutrient composition and overall energy restriction (33% reduction) were similar between groups. Body weight/composition, RMR, fasting...

  4. Comparative thermodynamic performance of some Rankine/Brayton cycle configurations for a low-temperature energy application

    Science.gov (United States)

    Lansing, F. L.

    1977-01-01

    Various configurations combining solar-Rankine and fuel-Brayton cycles were analyzed in order to find the arrangement which has the highest thermal efficiency and the smallest fuel share. A numerical example is given to evaluate both the thermodynamic performance and the economic feasibility of each configuration. The solar-assisted regenerative Rankine cycle was found to be leading the candidates from both points of energy utilization and fuel conservation.

  5. Biomass from agriculture in small-scale combined heat and power plants - A comparative life cycle assessment

    International Nuclear Information System (INIS)

    Kimming, M.; Sundberg, C.; Nordberg, A.; Baky, A.; Bernesson, S.; Noren, O.; Hansson, P.-A.

    2011-01-01

    Biomass produced on farm land is a renewable fuel that can prove suitable for small-scale combined heat and power (CHP) plants in rural areas. However, it can still be questioned if biomass-based energy generation is a good environmental choice with regards to the impact on greenhouse gas emissions, and if there are negative consequences of using of agricultural land for other purposes than food production. In this study, a simplified life cycle assessment (LCA) was conducted over four scenarios for supply of the entire demand of power and heat of a rural village. Three of the scenarios are based on utilization of biomass in 100 kW (e) combined heat and power (CHP) systems and the fourth is based on fossil fuel in a large-scale plant. The biomass systems analyzed were based on 1) biogas production with ley as substrate and the biogas combusted in a microturbine, 2) gasification of willow chips and the product gas combusted in an IC-engine and 3) combustion of willow chips for a Stirling engine. The two first scenarios also require a straw boiler. The results show that the biomass-based scenarios reduce greenhouse gas emissions considerably compared to the scenario based on fossil fuel, but have higher acidifying emissions. Scenario 1 has by far the best performance with respect to global warming potential and the advantage of utilizing a byproduct and thus not occupying extra land. Scenario 2 and 3 require less primary energy and less fossil energy input than 1, but set-aside land for willow production must be available. The low electric efficiency of scenario 3 makes it an unsuitable option.

  6. Sex differences associated with intermittent swim stress.

    Science.gov (United States)

    Warner, Timothy A; Libman, Matthew K; Wooten, Katherine L; Drugan, Robert C

    2013-11-01

    Various animal models of depression have been used to seek a greater understanding of stress-related disorders. However, there is still a great need for novel research in this area, as many individuals suffering from depression are resistant to current treatment methods. Women have a higher rate of depression, highlighting the need to investigate mechanisms of sex differences. Therefore, we employed a new animal model to assess symptoms of depression, known as intermittent swim stress (ISS). In this model, the animal experiences 100 trials of cold water swim stress. ISS has already been shown to cause signs of behavioral depression in males, but has yet to be assessed in females. Following ISS exposure, we looked at sex differences in the Morris water maze and forced swim test. The results indicated a spatial learning effect only in the hidden platform task between male and female controls, and stressed and control males. A consistent spatial memory effect was only seen for males exposed to ISS. In the forced swim test, both sexes exposed to ISS exhibited greater immobility, and the same males and females also showed attenuated climbing and swimming, respectively. The sex differences could be due to different neural substrates for males and females. The goal of this study was to provide the first behavioral examination of sex differences following ISS exposure, so the stage of estrous cycle was not assessed for the females. This is a necessary future direction for subsequent experiments. The current article highlights the importance of sex differences in response to stress.

  7. Reduced mRNA expression of PTGDS in peripheral blood mononuclear cells of rapid-cycling bipolar disorder patients compared with healthy control subjects

    DEFF Research Database (Denmark)

    Munkholm, Klaus; Peijs, Lone; Kessing, Lars Vedel

    2015-01-01

    was measured in 37 rapid-cycling bipolar disorder patients and 40 age- and gender-matched healthy control subjects using reverse transcription quantitative real-time polymerase chain reaction. Repeated measurements of PTGDS and AKR1C3 mRNA expression were obtained in various affective states during 6-12 months...... and compared with repeated measurements in healthy control subjects. RESULTS: Adjusted for age and gender, PTGDS mRNA expression was down-regulated in rapid-cycling bipolar disorder patients in a euthymic, depressive, and manic/hypomanic state compared with healthy control subjects. No difference in PTGDS m...

  8. The Yo-Yo intermittent recovery test

    DEFF Research Database (Denmark)

    Bangsbo, Jens; Iaia, F. Marcello; Krustrup, Peter

    2008-01-01

    The two Yo-Yo intermittent recovery (IR) tests evaluate an individual's ability to repeatedly perform intense exercise. The Yo-Yo IR level 1 (Yo-Yo IR1) test focuses on the capacity to carry out intermittent exercise leading to a maximal activation of the aerobic system, whereas Yo-Yo IR level 2...

  9. Lagrangian Statistics and Intermittency in Gulf of Mexico.

    Science.gov (United States)

    Lin, Liru; Zhuang, Wei; Huang, Yongxiang

    2017-12-12

    Due to the nonlinear interaction between different flow patterns, for instance, ocean current, meso-scale eddies, waves, etc, the movement of ocean is extremely complex, where a multiscale statistics is then relevant. In this work, a high time-resolution velocity with a time step 15 minutes obtained by the Lagrangian drifter deployed in the Gulf of Mexico (GoM) from July 2012 to October 2012 is considered. The measured Lagrangian velocity correlation function shows a strong daily cycle due to the diurnal tidal cycle. The estimated Fourier power spectrum E(f) implies a dual-power-law behavior which is separated by the daily cycle. The corresponding scaling exponents are close to -1.75 and -2.75 respectively for the time scale larger (resp. 0.1 ≤ f ≤ 0.4 day -1 ) and smaller (resp. 2 ≤ f ≤ 8 day -1 ) than 1 day. A Hilbert-based approach is then applied to this data set to identify the possible multifractal property of the cascade process. The results show an intermittent dynamics for the time scale larger than 1 day, while a less intermittent dynamics for the time scale smaller than 1 day. It is speculated that the energy is partially injected via the diurnal tidal movement and then transferred to larger and small scales through a complex cascade process, which needs more studies in the near future.

  10. Intermittent Hypoxia Causes Inflammation and Injury to Human Adult Cardiac Myocytes.

    Science.gov (United States)

    Wu, Jing; Stefaniak, Joanna; Hafner, Christina; Schramel, Johannes Peter; Kaun, Christoph; Wojta, Johann; Ullrich, Roman; Tretter, Verena Eva; Markstaller, Klaus; Klein, Klaus Ulrich

    2016-02-01

    Intermittent hypoxia may occur in a number of clinical scenarios, including interruption of myocardial blood flow or breathing disorders such as obstructive sleep apnea. Although intermittent hypoxia has been linked to cardiovascular and cerebrovascular disease, the effect of intermittent hypoxia on the human heart is not fully understood. Therefore, in the present study, we compared the cellular responses of cultured human adult cardiac myocytes (HACMs) exposed to intermittent hypoxia and different conditions of continuous hypoxia and normoxia. HACMs were exposed to intermittent hypoxia (0%-21% O2), constant mild hypoxia (10% O2), constant severe hypoxia (0% O2), or constant normoxia (21% O2), using a novel cell culture bioreactor with gas-permeable membranes. Cell proliferation, lactate dehydrogenase release, vascular endothelial growth factor release, and cytokine (interleukin [IL] and macrophage migration inhibitory factor) release were assessed at baseline and after 8, 24, and 72 hours of exposure. A signal transduction pathway finder array was performed to determine the changes in gene expression. In comparison with constant normoxia and constant mild hypoxia, intermittent hypoxia induced earlier and greater inflammatory response and extent of cell injury as evidenced by lower cell numbers and higher lactate dehydrogenase, vascular endothelial growth factor, and proinflammatory cytokine (IL-1β, IL-6, IL-8, and macrophage migration inhibitory factor) release. Constant severe hypoxia showed more detrimental effects on HACMs at later time points. Pathway analysis demonstrated that intermittent hypoxia primarily altered gene expression in oxidative stress, Wnt, Notch, and hypoxia pathways. Intermittent and constant severe hypoxia, but not constant mild hypoxia or normoxia, induced inflammation and cell injury in HACMs. Cell injury occurred earliest and was greatest after intermittent hypoxia exposure. Our in vitro findings suggest that intermittent hypoxia

  11. Managing server clusters on intermittent power

    Directory of Open Access Journals (Sweden)

    Navin Sharma

    2015-12-01

    Full Text Available Reducing the energy footprint of data centers continues to receive significant attention due to both its financial and environmental impact. There are numerous methods that limit the impact of both factors, such as expanding the use of renewable energy or participating in automated demand-response programs. To take advantage of these methods, servers and applications must gracefully handle intermittent constraints in their power supply. In this paper, we propose blinking—metered transitions between a high-power active state and a low-power inactive state—as the primary abstraction for conforming to intermittent power constraints. We design Blink, an application-independent hardware–software platform for developing and evaluating blinking applications, and define multiple types of blinking policies. We then use Blink to design both a blinking version of memcached (BlinkCache and a multimedia cache (GreenCache to demonstrate how application characteristics affect the design of blink-aware distributed applications. Our results show that for BlinkCache, a load-proportional blinking policy combines the advantages of both activation and synchronous blinking for realistic Zipf-like popularity distributions and wind/solar power signals by achieving near optimal hit rates (within 15% of an activation policy, while also providing fairer access to the cache (within 2% of a synchronous policy for equally popular objects. In contrast, for GreenCache, due to multimedia workload patterns, we find that a staggered load proportional blinking policy with replication of the first chunk of each video reduces the buffering time at all power levels, as compared to activation or load-proportional blinking policies.

  12. ANISOTROPIC INTERMITTENCY OF MAGNETOHYDRODYNAMIC TURBULENCE

    International Nuclear Information System (INIS)

    Osman, K. T.; Kiyani, K. H.; Chapman, S. C.; Hnat, B.

    2014-01-01

    A higher-order multiscale analysis of spatial anisotropy in inertial range magnetohydrodynamic turbulence is presented using measurements from the STEREO spacecraft in fast ambient solar wind. We show for the first time that, when measuring parallel to the local magnetic field direction, the full statistical signature of the magnetic and Elsässer field fluctuations is that of a non-Gaussian globally scale-invariant process. This is distinct from the classic multiexponent statistics observed when the local magnetic field is perpendicular to the flow direction. These observations are interpreted as evidence for the weakness, or absence, of a parallel magnetofluid turbulence energy cascade. As such, these results present strong observational constraints on the statistical nature of intermittency in turbulent plasmas

  13. Prolonged Intermittent Renal Replacement Therapy.

    Science.gov (United States)

    Edrees, Fahad; Li, Tingting; Vijayan, Anitha

    2016-05-01

    Prolonged intermittent renal replacement therapy (PIRRT) is becoming an increasingly popular alternative to continuous renal replacement therapy in critically ill patients with acute kidney injury. There are significant practice variations in the provision of PIRRT across institutions, with respect to prescription, technology, and delivery of therapy. Clinical trials have generally demonstrated that PIRRT is non-inferior to continuous renal replacement therapy regarding patient outcomes. PIRRT offers cost-effective renal replacement therapy along with other advantages such as early patient mobilization and decreased nursing time. However, due to lack of standardization of the procedure, PIRRT still poses significant challenges, especially pertaining to appropriate drug dosing. Future guidelines and clinical trials should work toward developing consensus definitions for PIRRT and ensure optimal delivery of therapy. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  14. Intermittent cryogen spray cooling for optimal heat extraction during dermatologic laser treatment

    Science.gov (United States)

    Majaron, Boris; Svaasand, Lars O.; Aguilar, Guillermo; Nelson, J. Stuart

    2002-09-01

    Fast heat extraction is critically important to obtain the maximal benefit of cryogen spray cooling (CSC) during laser therapy of shallow skin lesions, such as port wine stain birthmarks. However, a film of liquid cryogen can build up on the skin surface, impairing heat transfer due to the relatively low thermal conductivity and higher temperature of the film as compared to the impinging spray droplets. In an attempt to optimize the cryogen mass flux, while minimally affecting other spray characteristics, we apply a series of 10 ms spurts with variable duty cycles. Heat extraction dynamics during such intermittent cryogen sprays were measured using a custom-made metal-disc detector. The highest cooling rates were observed at moderate duty cycle levels. This confirms the presence, and offers a practical way to eliminate the adverse effect of liquid cryogen build-up on the sprayed surface. On the other hand, lower duty cycles allow a substantial reduction in the average rate of heat extraction, enabling less aggressive and more efficient CSC for treatment of deeper targets, such as hair follicles.

  15. Comparing the performances of electrochemical sensors using p-aminophenol redox cycling by different reductants on gold electrodes modified with self-assembled monolayers

    International Nuclear Information System (INIS)

    Xia, Ning; Ma, Fengji; Zhao, Feng; He, Qige; Du, Jimin; Li, Sujuan; Chen, Jing; Liu, Lin

    2013-01-01

    Highlights: • Performances of p-AP redox cycling using different reductants on gold surface are compared. • Background current decreases in order of hydrazine, Na 2 SO 3 , NaBH 4 , NADH, cysteamine, and TCEP. • Chemical reaction rate with QI increases in order of NADH, TCEP, and cysteamine. • NADH, TCEP and cysteamine are suitable for p-AP redox cycling on gold electrode. -- Abstract: p-Aminophenol (p-AP) redox cycling using chemical reductants is one strategy for developing sensitive electrochemical sensors. However, most of the reported reductants are only used on indium-tin oxide (ITO) electrodes but not gold electrodes due to the high background current caused by the oxidation reaction of the reductants on the highly electrocatalytic gold electrodes. Therefore, new strategies and/or reductants are in demand for expanding the application of p-AP redox cycling on gold electrodes. In this work, we compared the performances of several reductants in p-AP redox cycling on self-assembled monolayers (SAMs)-modified gold electrodes. Among the tested reagents, nicotinamide adenine dinucleotide (NADH), tris(2-carboxyethyl)phosphine (TCEP) and cysteamine were demonstrated to be suitable for p-AP redox cycling on the alkanethiol-modified gold electrodes because of their low background current. The rate of chemical reaction between reductants and p-quinone imine (QI, the electrochemically oxidized product of p-AP) increases in the order of NADH −1 was achieved. We believe that our work will be valuable for the development of electrochemical sensors using p-AP redox cycling on gold electrodes

  16. Comparing the Life Cycle Energy Consumption, Global Warming and Eutrophication Potentials of Several Water and Waste Service Options

    Science.gov (United States)

    Managing the water-energy-nutrient nexus for the built environment requires, in part, a full system analysis of energy consumption, global warming and eutrophication potentials of municipal water services. As an example, we evaluated the life cycle energy use, greenhouse gas (GHG...

  17. A comparative life cycle analysis of low power PV lighting products for rural areas in South East Asia

    NARCIS (Netherlands)

    Durlinger, Bart; Durlinger, B.P.J.; Reinders, Angelina H.M.E.; Toxopeus, Marten E.

    2012-01-01

    This paper evaluates the environmental effects of low power PV lighting products, which are increasingly used in rural areas in South East Asia, by means of a life cycle analysis (LCA). The main goals of the project are to determine (1) the environmental impacts, (2) which parts are contributing to

  18. Comparing Green and Grey Infrastructure Using Life Cycle Cost and Environmental Impact: A Rain Garden Case Study in Cincinnati, OH.

    Science.gov (United States)

    Green infrastructure is quickly gaining ground as a less costly, greener alternative to traditional methods of stormwater management. One popular form of green infrastructure is the use of rain gardens to capture and infiltrate stormwater in to the ground. We used life cycle asse...

  19. A Comparative-Study on Nutrient Cycling in Wet Heathland Ecosystems.2.Litter Decomposition and Nutrient Mineralization

    NARCIS (Netherlands)

    Berendse, F.; Bobbink, R.; Rouwenhorst, G.

    1989-01-01

    The concept of the relative nutrient requirement (L n) that was introduced in the first paper of this series is used to analyse the effects of the dominant plant population on nutrient cycling and nutrient mineralization in wet heathland ecosystems. A distinction is made between the effect that the

  20. Comparative Environmental Life Cycle Assessment of Oxyfuel and Post-combustion Capture with MEA and AMP/PZ - Case Studies from the EDDiCCUT Project

    NARCIS (Netherlands)

    Oreggioni, Gabriel D.; Singh, Bhawna; Hung, Christine Roxanne; Van Der Spek, Mijndert W.; Skagestad, Ragnhild; Eldrup, Nils Henrik; Ramirez, Andrea; Strømman, Anders Hammer

    2017-01-01

    This work presents the results of a comparative life cycle assessment study for three CCS technologies applied to a coal-fired power plant: post-combustion capture with MEA, post combustion capture with AMP/PZ and cryogenic oxy-fuel. This study has been performed in the context of the EDDiCCUT

  1. Comparative life cycle assessment of ghana-made bamboo-frame bicycle and conventional bicycles assembled and used in the Netherlands

    NARCIS (Netherlands)

    Agyekum, E.O.; Fortuin, K.P.J.; Harst, van der E.J.M.

    2014-01-01

    In order to assess the sustainability of bamboo-framed bicycles produced in Ghana, an environmental and social life cycle assessments (LCA) were performed. For the environmental LCA, a bamboo-frame bicycle was compared with aluminium- and steel-frame bicycles, focussing on processes related to the

  2. Intermittent Auscultation for Intrapartum Fetal Heart Rate Surveillance: American College of Nurse-Midwives.

    Science.gov (United States)

    2015-01-01

    Fetal heart rate surveillance is a standard component of intrapartum care. The fetal heart rate can be evaluated using intermittent auscultation or electronic fetal monitoring. Research that has compared these 2 strategies found them to be equivalent with respect to long-term neonatal outcomes. The purpose of this clinical bulletin by the American College of Nurse-Midwives is to review the evidence for use of intermittent auscultation and provide recommendations for intermittent auscultation technique, interpretation, and documentation. © 2015 by the American College of Nurse-Midwives.

  3. A SYSTEMATIC REVIEW AND META-ANALYSIS COMPARING CARDIOPULMONARY EXERCISE TEST VALUES OBTAINED FROM THE ARM CYCLE AND THE LEG CYCLE RESPECTIVELY IN HEALTHY ADULTS

    DEFF Research Database (Denmark)

    Larsen, Rasmus Tolstrup; Christensen, Jan; Tang, Lars Hermann

    2016-01-01

    a systematic review and meta-analysis of the difference in VO2max achieved by AC compared to LC in healthy adults and to explore factors that may be predictive of this difference. METHODS: MEDLINE, EMBASE, CINAHL, and PEDro were searched in April 2015. The differences in VO2max (ACLCdiff) were pooled across....../min with a mean ACLCratio of 0.70. The ACLCdiff was lower in studies with higher mean age and lower aerobic capacity. CONCLUSION: There is linear association between the AC and LC values in healthy adults. The AC values were on average 70% of the LC values. The magnitude of this difference appeared to be reduced...

  4. Pulsar wind model for the spin-down behavior of intermittent pulsars

    Energy Technology Data Exchange (ETDEWEB)

    Li, L.; Tong, H.; Yan, W. M.; Yuan, J. P.; Wang, N. [Xinjiang Astronomical Observatory, Chinese Academy of Sciences, Urumqi, Xinjiang 830011 (China); Xu, R. X., E-mail: tonghao@xao.ac.cn [School of Physics, Peking University, Beijing (China)

    2014-06-10

    Intermittent pulsars are part-time radio pulsars. They have higher slow down rates in the on state (radio-loud) than in the off state (radio-quiet). This gives evidence that particle wind may play an important role in pulsar spindown. The effect of particle acceleration is included in modeling the rotational energy loss rate of the neutron star. Applying the pulsar wind model to the three intermittent pulsars (PSR B1931+24, PSR J1841–0500, and PSR J1832+0029) allows their magnetic fields and inclination angles to be calculated simultaneously. The theoretical braking indices of intermittent pulsars are also given. In the pulsar wind model, the density of the particle wind can always be the Goldreich-Julian density. This may ensure that different on states of intermittent pulsars are stable. The duty cycle of particle wind can be determined from timing observations. It is consistent with the duty cycle of the on state. Inclination angle and braking index observations of intermittent pulsars may help to test different models of particle acceleration. At present, the inverse Compton scattering induced space charge limited flow with field saturation model can be ruled out.

  5. Identification of decisive factors for greenhouse gas emissions in comparative life cycle assessments of food waste management – an analytical review

    DEFF Research Database (Denmark)

    Bernstad, Anna; Wenzel, Henrik; Jansen, Jes la Cour

    2016-01-01

    . Secondly, to identify decisive factors in general and related to system boundary settings in particular, in reviewed studies. A number of criteria were constructed for identification of relevant comparative life cycle assessments, resulting in selection of nineteen studies, containing 103 different......A review of existing life cycle assessments on food waste management was made with two main aims. Firstly, to make an overview of the assessments of the global warming potential from the treatment alternatives incineration, landfill, anaerobic digestion and compost in studies reported in literature...

  6. Development of Comparative Toxicity Potentials of TiO2 Nanoparticles for Use in Life Cycle Assessment

    DEFF Research Database (Denmark)

    Ettrup, Kim; Kounina, Anna; Hansen, Steffen Foss

    2017-01-01

    for TiO2 nanoparticles (TiO2-NP) for use in LCA. We adapted the USEtox 2.0 consensus model to integrate the SimpleBox4Nano fate model, and we populated the resulting model with TiO2-NP specific data. We thus calculated CTP values for TiO2 nanoparticles for air, water, and soil emission compartments...... in earlier studies. Assumptions, which were performed in those previous studies because of lack of data and knowledge at the time they were made, primarily explain such discrepancies. For future assessment of potential toxic impacts of TiO2 nanoparticles in LCA studies, we therefore recommend the use of our......Studies have shown that releases of nanoparticles may take place through the life cycle of products embedding nanomaterials, thus resulting in potential impacts on ecosystems and human health. While several life cycle assessment (LCA) studies have assessed such products, only a few of them have...

  7. Comparative of fuel cycle cost for light water nuclear power plants; Uporedna analiza cene gorivnog ciklusa lakovodne nuklearne elektrane

    Energy Technology Data Exchange (ETDEWEB)

    Kocic, A; Dimitrijevic, Z [Boris Kidric Institute of nuclear sciences, Vinca, Belgrade (Yugoslavia)

    1978-07-01

    Starting from ost general fuel cycle scheme for light water reactors this article deals with conceptual differences of BWR, PWR and WWER as well as with the influence of certain phases of fuel cycle on economic parameters of an equivalent 1000 MWe reactor using a computer program CENA /1/ and typical parameters of each reactor type. An analysis of two particular power plants 628 MWe and 440 MWe WWER by means of the same program is given in the second part of this paper taking into account the differences of in-core fuel management. This second approach is especially interesting for the economy of the power plant itself in the period of planning. (author)

  8. Intermittent cranial lung herniation in two dogs.

    Science.gov (United States)

    Guglielmini, Carlo; De Simone, Antonio; Valbonetti, Luca; Diana, Alessia

    2007-01-01

    Two aged dogs with chronic obstructive airway disease were evaluated because of intermittent swelling of the ventral cervical region. Radiographs made at expiration and caudal positioning of the forelimbs allowed identification of intermittent cervical lung herniation of the left and right cranial lung lobe in both dogs. Pulmonary hyperinflation, increased expiratory effort, and chronic coughing were considered responsible for the lung herniation. Cervical lung hernia should be included in the differential diagnoses of intermittent cervical swelling in dogs with chronic respiratory disorders associated with increased expiratory effort and chronic coughing.

  9. Comparing the environmental footprints of home-care and personal-hygiene products: the relevance of different life-cycle phases.

    Science.gov (United States)

    Koehler, Annette; Wildbolz, Caroline

    2009-11-15

    An in-depth life-cycle assessment of nine home-care and personal-hygiene products was conducted to determine the ecological relevance of different life-cycle phases and compare the environmental profiles of products serving equal applications. Using detailed data from industry and consumer-behavior studies a broad range of environmental impacts were analyzed to identify the main drivers in each life-cycle stage and potentials for improving the environmental footprints. Although chemical production significantly adds to environmental burdens, substantial impacts are caused in the consumer-use phase. As such, this research provides recommendations for product development, supply chain management, product policies, and consumer use. To reduce environmental burdens products should, for instance, be produced in concentrated form, while consumers should apply correct product dosages and low water temperatures during product application.

  10. Frequency and magnitude of intermittent hypoxia modulate endothelial wound healing in a cell culture model of sleep apnea.

    Science.gov (United States)

    Campillo, Noelia; Falcones, Bryan; Montserrat, Josep M; Gozal, David; Obeso, Ana; Gallego-Martin, Teresa; Navajas, Daniel; Almendros, Isaac; Farré, Ramon

    2017-11-01

    Intermittent hypoxia (IH) has been implicated in the cardiovascular consequences of obstructive sleep apnea (OSA). However, the lack of suitable experimental systems has precluded assessment as to whether IH is detrimental, protective, or both for the endothelium. The aim of the work was to determine the effects of frequency and amplitude of IH oxygenation swings on aortic endothelial wound healing. Monolayers of human primary endothelial cells were wounded and subjected to constant oxygenation (1%, 4%, 13%, or 20% O 2 ) or IH at different frequencies (0.6, 6, or 60 cycles/h) and magnitude ranges (13-4% O 2 or 20-1% O 2 ), using a novel well-controlled system, with wound healing being measured after 24 h. Cell monolayer repair was similar at 20% O 2 and 13% O 2 , but was considerably increased (approximately twofold) in constant hypoxia at 4% O 2 The magnitude and frequency of IH considerably modulated wound healing. Cycles ranging 13-4% O 2 at the lowest frequency (0.6 cycles/h) accelerated endothelial wound healing by 102%. However, for IH exposures consisting of 20% to 1% O 2 oscillations, wound closure was reduced compared with oscillation in the 13-4% range (by 74% and 44% at 6 cycles/h and 0.6 cycles/h, respectively). High-frequency IH patterns simulating severe OSA (60 cycles/h) did not significantly modify endothelial wound closure, regardless of the oxygenation cycle amplitude. In conclusion, the frequency and magnitude of hypoxia cycling in IH markedly alter wound healing responses and emerge as key factors determining how cells will respond in OSA. NEW & NOTEWORTHY Intermittent hypoxia (IH) induces cardiovascular consequences in obstructive sleep apnea (OSA) patients. However, the vast array of frequencies and severities of IH previously employed in OSA-related experimental studies has led to controversial results on the effects of IH. By employing an optimized IH experimental system here, we provide evidence that the frequency and magnitude of IH

  11. Water Quality and Quantity in Intermittent and Continuous Piped Water Supplies in Hubli-Dharwad, India

    OpenAIRE

    Kumpel, Emily Katherine

    2013-01-01

    In at least 45 low- and middle-income countries, piped water systems deliver water for limited durations. Few data are available of the impact of intermittent water supply (IWS) on the water quality and quantity delivered to households. This thesis examines the impact of intermittently supplied piped water on the quality and quantity of water delivered to residential taps in Hubli-Dharwad, India, when compared to continuous piped water supply. A framework for understanding the pathways throug...

  12. Chronic intermittent hyperoxia alters the development of the hypoxic ventilatory response in neonatal rats.

    Science.gov (United States)

    Logan, Sarah; Tobin, Kristina E; Fallon, Sarah C; Deng, Kevin S; McDonough, Amy B; Bavis, Ryan W

    2016-01-01

    Chronic exposure to sustained hyperoxia alters the development of the respiratory control system, but the respiratory effects of chronic intermittent hyperoxia have rarely been investigated. We exposed newborn rats to short, repeated bouts of 30% O2 or 60% O2 (5 bouts h(-1)) for 4-15 days and then assessed their hypoxic ventilatory response (HVR; 10 min at 12% O2) by plethysmography. The HVR tended to be enhanced by intermittent hyperoxia at P4 (early phase of the HVR), but it was significantly reduced at P14-15 (primarily late phase of the HVR) compared to age-matched controls; the HVR recovered when individuals were returned to room air and re-studied as adults. To investigate the role of carotid body function in this plasticity, single-unit carotid chemoafferent activity was recorded in vitro. Intermittent hyperoxia tended to decrease spontaneous action potential frequency under normoxic conditions but, contrary to expectations, hypoxic responses were only reduced at P4 (not at P14) and only in rats exposed to higher O2 levels (i.e., intermittent 60% O2). Rats exposed to intermittent hyperoxia had smaller carotid bodies, and this morphological change may contribute to the blunted HVR. In contrast to rats exposed to intermittent hyperoxia beginning at birth, two weeks of intermittent 60% O2 had no effect on the HVR or carotid body size of rats exposed beginning at P28; therefore, intermittent hyperoxia-induced respiratory plasticity appears to be unique to development. Although both intermittent and sustained hyperoxia alter carotid body development and the HVR of rats, the specific effects and time course of this plasticity differs. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Intermittent sea-level acceleration

    Science.gov (United States)

    Olivieri, M.; Spada, G.

    2013-10-01

    Using instrumental observations from the Permanent Service for Mean Sea Level (PSMSL), we provide a new assessment of the global sea-level acceleration for the last ~ 2 centuries (1820-2010). Our results, obtained by a stack of tide gauge time series, confirm the existence of a global sea-level acceleration (GSLA) and, coherently with independent assessments so far, they point to a value close to 0.01 mm/yr2. However, differently from previous studies, we discuss how change points or abrupt inflections in individual sea-level time series have contributed to the GSLA. Our analysis, based on methods borrowed from econometrics, suggests the existence of two distinct driving mechanisms for the GSLA, both involving a minority of tide gauges globally. The first effectively implies a gradual increase in the rate of sea-level rise at individual tide gauges, while the second is manifest through a sequence of catastrophic variations of the sea-level trend. These occurred intermittently since the end of the 19th century and became more frequent during the last four decades.

  14. Intermittent ileocoecal intususception in adult

    International Nuclear Information System (INIS)

    Cambal, M.; Zonca, P.; Maly, T.

    2013-01-01

    Aim: Aim of our paper is to present a case-report of chronic invagination in adult patient. Material: 28-years old woman with one year history of intermittent abdominal pain with symptoms of subileus state. She has underwent abdominal ultrasonography, abdominal X-ray, colonoscopy, irigography and abdominal CT. Appendectomy indicated for diagnosis of chronic appendicitis did not improve symptoms. Consecutively during acute problems were irigography and CT performed and diagnosis of an incomplete colon transversum obstruction of uncertain origin was established. There was stated suspicion of an intususception and patient was due to a repeated gastrointestinal passage indicated for an explorative laparotomy. During operation there was identified threefold invagination – colo-colonic, ileo-colonic and ileo-ileal. As a leading point of invagination was found in terminal ileum intraluminal polypous tumor 5 cm in diameter. Because of the secondary chronic changes of right colon wall and terminal ileum wall, after partial desinvagination right hemicolectomy was performed. Results: Patient was primary healed and now is without any subjective problems. Conclusion: Invagination is an acute abdominal event of obturative-strangulative type and it mainly occurs in infantile age. It is astonishing how long were patient´s difficulties lasting without obvious acute ileus. It is necessary in clinical practice to think on these rare reasons of gastrointestinal passage disorders. (author)

  15. White adipose tissue coloring by intermittent fasting.

    Science.gov (United States)

    Kivelä, Riikka; Alitalo, Kari

    2017-11-01

    Intermittent fasting (IF) has been shown to promote metabolic health in several organisms. Two recent papers show that IF induces white adipose tissue beiging and increases thermogenesis, which improves metabolic health in mice.

  16. On-line intermittent connector anomaly detection

    Data.gov (United States)

    National Aeronautics and Space Administration — This paper investigates a non-traditional use of differential current sensor and current sensor to detect intermittent disconnection problems in connectors. An...

  17. Intermittent chaotic chimeras for coupled rotators

    DEFF Research Database (Denmark)

    Olmi, Simona; Martens, Erik Andreas; Thutupalli, Shashi

    2015-01-01

    Two symmetrically coupled populations of N oscillators with inertia m display chaotic solutions with broken symmetry similar to experimental observations with mechanical pendulums. In particular, we report evidence of intermittent chaotic chimeras, where one population is synchronized and the other...

  18. Feigenbaum attractor and intermittency in particle collisions

    International Nuclear Information System (INIS)

    Batunin, A.V.

    1992-01-01

    The hypothesis is proposed that the Feigenbaum attractor arising as a limit set in an infinite pichfork bifurcation sequence for unimodal one-dimensional maps underlies the intermittency phenomena in particle collisions. 23 refs.; 8 figs

  19. Tokamak burn cycle study: a data base for comparing long pulse and steady-state power reactors

    International Nuclear Information System (INIS)

    Ehst, D.A.; Brooks, J.N.; Cha, Y.; Evans, K. Jr.; Hassanein, A.; Kim, S.; Majumdar, S.; Misra, B.; Stevens, H.C.

    1983-11-01

    Several distinct operating modes (conventional ohmic, noninductive steady state, internal transformer, etc.) have been proposed for tokamaks. Our study focuses on capital costs and lifetime limitations of reactor subsystems in an attempt to quantify sensitivity to pulsed operation. Major problem areas considered include: thermal fatigue on first wall, limiter/divertor; thermal energy storage; fatigue and eddy current heating in toroidal field coils; electric power supply costs; and noninductive driver costs. We assume a high availability and low cost of energy will be mandatory for a commercial fusion reactor, and we characterize improvements in physics (current drive efficiency) and engineering (superior materials) which will help achieve these goals for different burn cycles

  20. [Role of hippocampal neuronal intracellular calcium overload in modulating cognitive dysfunction and the neuronprotective effect of mematine in a mouse model of chronic intermittent hypoxia].

    Science.gov (United States)

    Ming, Hong; Chen, Rui; Wang, Jing; Ju, Jingmei; Sun, Li; Zhang, Guoxing

    2014-12-01

    To investigate the role of hippocampal intracellular calcium overload in modulating cognitive dysfunction and the neuronprotective effect of mematine in a mouse model of chronic intermittent hypoxia. 45 ICR male mice were randomly divided into 3 groups: the unhandled control group (UC group, n = 15), the chronic intermittent hypoxia (CIH group, n = 15) and the pretreatment memantine group (MEM group, n = 15). CIH and MEM mice were subjected to intermittent hypoxia while UC mice to room air for 8 h per day during 4 weeks. Mice in the MEM group were pretreated with memantine (5 mg/kg) by intraperitoneal injection before the cycle started, and those in the UC group and the CIH group were treated with same volume of physiological saline. Neurobehavioral assessments were performed by Open filed and Morris water maze, [Ca²⁺]i in hippocampal neurons was evaluate by flow cytometry, and the expression of cleaved caspase-3, phospho-ERK1/2 in hippocampus were detected by Western blotting. Compared with the UC group, CIH mice displayed markedly more locomotor activity (P overload, neuron apoptosis, dephosphorylation of ERK1/2, which can be attenuated by memantine. Memantine may have a therapeutic effect in the neurocognitive impairment associated with OSAHS.

  1. Simulating obstructive sleep apnea patients' oxygenation characteristics into a mouse model of cyclical intermittent hypoxia.

    Science.gov (United States)

    Lim, Diane C; Brady, Daniel C; Po, Pengse; Chuang, Li Pang; Marcondes, Laise; Kim, Emily Y; Keenan, Brendan T; Guo, Xiaofeng; Maislin, Greg; Galante, Raymond J; Pack, Allan I

    2015-03-01

    Mouse models of cyclical intermittent hypoxia (CIH) are used to study the consequences of both hypoxia and oxidative stress in obstructive sleep apnea (OSA). Whether or not a mouse model of CIH that simulates OSA patients' oxygenation characteristics would translate into improved patient care remains unanswered. First we identified oxygenation characteristics using the desaturation and resaturation time in 47 OSA subjects from the Molecular Signatures of Obstructive Sleep Apnea Cohort (MSOSA). We observe that a cycle of intermittent hypoxia is not sinusoidal; specifically, desaturation time increases in an almost linear relationship to the degree of hypoxia (nadir), whereas resaturation time is somewhat constant (∼15 s), irrespective of the nadir. Second, we modified the Hycon mouse model of CIH to accommodate a 15-s resaturation time. Using this modified CIH model, we explored whether a short resaturation schedule (15 s), which includes the characteristics of OSA patients, had a different effect on levels of oxidative stress (i.e., urinary 8,12-iso-iPF2α-VI levels) compared with sham and a long resaturation schedule (90 s), a schedule that is not uncommon in rodent models of CIH. Results suggest that shorter resaturation time may result in a higher level of 8,12-iso-iPF2α-VI compared with long resaturation or sham conditions. Therefore, simulating the rodent model of CIH to reflect this and other OSA patients' oxygenation characteristics may be worthy of consideration to better understand the effects of hypoxia, oxidative stress, and their interactions. Copyright © 2015 the American Physiological Society.

  2. Comparative analysis of methods for integrating various environmental impacts as a single index in life cycle assessment

    International Nuclear Information System (INIS)

    Ji, Changyoon; Hong, Taehoon

    2016-01-01

    Previous studies have proposed several methods for integrating characterized environmental impacts as a single index in life cycle assessment. Each of them, however, may lead to different results. This study presents internal and external normalization methods, weighting factors proposed by panel methods, and a monetary valuation based on an endpoint life cycle impact assessment method as the integration methods. Furthermore, this study investigates the differences among the integration methods and identifies the causes of the differences through a case study in which five elementary school buildings were used. As a result, when using internal normalization with weighting factors, the weighting factors had a significant influence on the total environmental impacts whereas the normalization had little influence on the total environmental impacts. When using external normalization with weighting factors, the normalization had more significant influence on the total environmental impacts than weighing factors. Due to such differences, the ranking of the five buildings varied depending on the integration methods. The ranking calculated by the monetary valuation method was significantly different from that calculated by the normalization and weighting process. The results aid decision makers in understanding the differences among these integration methods, and, finally, help them select the method most appropriate for the goal at hand.

  3. Comparative study of measured heart cycle phase durations: standard lead ECG versus original ascending aorta lead ECG

    Directory of Open Access Journals (Sweden)

    Sergey V. Kolmakov

    2012-11-01

    Full Text Available Aims The present paper aims at evaluating the existing difference in duration measurements of the same heart cycle phases in the standard V3, V4, V5, V6 leads ECG versus original HDA lead ECG of the ascending aorta. Materials and methods The method of changing the filter pass band is used. Its essence is in artificial changing of the conditions of the signal recording carrying the informative indications of the initial information used in hemodynamic equations. The method also enables calculating the percentage deviation from the initial values. The principle of balance of the blood volume entering the heart and the blood volume leaving the heart is used to trace the minimal deviations and their respective recording conditions. Results In each of the V3, V4, V5, V6 ECG leads durations of the same phases have different values. The values measured on the ECG of the ascending aorta and those measured using the standard V4 ECG lead differ slightly. Conclusion For heart cycle phase analysis it is possible to use only the ECG of the ascending aorta and V4 standard lead ECG. Using conventional standard ECG leads causes an error up to 25%.

  4. Comparative analysis of methods for integrating various environmental impacts as a single index in life cycle assessment

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Changyoon, E-mail: changyoon@yonsei.ac.kr; Hong, Taehoon, E-mail: hong7@yonsei.ac.kr

    2016-02-15

    Previous studies have proposed several methods for integrating characterized environmental impacts as a single index in life cycle assessment. Each of them, however, may lead to different results. This study presents internal and external normalization methods, weighting factors proposed by panel methods, and a monetary valuation based on an endpoint life cycle impact assessment method as the integration methods. Furthermore, this study investigates the differences among the integration methods and identifies the causes of the differences through a case study in which five elementary school buildings were used. As a result, when using internal normalization with weighting factors, the weighting factors had a significant influence on the total environmental impacts whereas the normalization had little influence on the total environmental impacts. When using external normalization with weighting factors, the normalization had more significant influence on the total environmental impacts than weighing factors. Due to such differences, the ranking of the five buildings varied depending on the integration methods. The ranking calculated by the monetary valuation method was significantly different from that calculated by the normalization and weighting process. The results aid decision makers in understanding the differences among these integration methods, and, finally, help them select the method most appropriate for the goal at hand.

  5. Validity of the RAST for evaluating anaerobic power performance as compared to Wingate test in cycling athletes

    Directory of Open Access Journals (Sweden)

    Marcos Roberto Queiroga

    2013-12-01

    Full Text Available The validity of the Running-based Anaerobic Sprint Test (RAST was investigated to evaluate the anaerobic power performance in comparison to Wingate test in cycling athletes. Ten mountain-bike male cyclists (28.0±7.3 years randomly performed Wingate Test and RAST with two trials each. After several anthropometric measurements, peak power (PP, mean power (MP and fatigue index (FI for RAST and Wingate Test were analyzed using Student's paired t-test, Pearson's linear correlation test (r and Bland and Altman's plots. Results showed that, with the exception of FI (33.8±4.6% vs. 37.8±7.9%; r=0.172, significant differences were detected between the Wingate and RAST tests with regard to PP and MP. Although there was a strong correlation for PP and MP, or rather, 0.831 and 0.714 respectively, agreement of analysis between Wingate and RAST protocols was low. The above suggested that RAST was not appropriate to evaluate the performance of anaerobic power by Wingate test in cycling athletes.

  6. Comparative 4-E analysis of a bottoming pure NH3 and NH3-H2O mixture based power cycle for condenser waste heat recovery

    Science.gov (United States)

    Khankari, Goutam; Karmakar, Sujit

    2017-06-01

    This paper proposes a comparative performance analysis based on 4-E (Energy, Exergy, Environment, and Economic) of a bottoming pure Ammonia (NH3) based Organic Rankine Cycle (ORC) and Ammonia-water (NH3-H2O) based Kalina Cycle System 11(KCS 11) for additional power generation through condenser waste heat recovery integrated with a conventional 500MWe Subcritical coal-fired thermal power plant. A typical high-ash Indian coal is used for the analysis. The flow-sheet computer programme `Cycle Tempo' is used to simulate both the cycles for thermodynamic performance analysis at different plant operating conditions. Thermodynamic analysis is done by varying different NH3 mass fraction in KCS11 and at different turbine inlet pressure in both ORC and KCS11. Results show that the optimum operating pressure of ORC and KCS11 with NH3 mass fraction of 0.90 are about 15 bar and 11.70 bar, respectively and more than 14 bar of operating pressure, the plant performance of ORC integrated power plant is higher than the KCS11 integrated power plant and the result is observed reverse below this pressure. The energy and exergy efficiencies of ORC cycle are higher than the KCS11 by about 0.903 % point and 16.605 % points, respectively under similar saturation vapour temperature at turbine inlet for both the cycles. Similarly, plant energy and exergy efficiencies of ORC based combined cycle power plant are increased by 0.460 % point and 0.420 % point, respectively over KCS11 based combined cycle power plant. Moreover, the reduction of CO2 emission in ORC based combined cycle is about 3.23 t/hr which is about 1.5 times higher than the KCS11 based combined cycle power plant. Exergy destruction of the evaporator in ORC decreases with increase in operating pressure due to decrease in temperature difference of heat exchanging fluids. Exergy destruction rate in the evaporator of ORC is higher than KCS11 when the operating pressure of ORC reduces below 14 bar. This happens due to variable

  7. COMPAR

    International Nuclear Information System (INIS)

    Kuefner, K.

    1976-01-01

    COMPAR works on FORTRAN arrays with four indices: A = A(i,j,k,l) where, for each fixed k 0 ,l 0 , only the 'plane' [A(i,j,k 0 ,l 0 ), i = 1, isub(max), j = 1, jsub(max)] is held in fast memory. Given two arrays A, B of this type COMPAR has the capability to 1) re-norm A and B ind different ways; 2) calculate the deviations epsilon defined as epsilon(i,j,k,l): =[A(i,j,k,l) - B(i,j,k,l)] / GEW(i,j,k,l) where GEW (i,j,k,l) may be chosen in three different ways; 3) calculate mean, standard deviation and maximum in the array epsilon (by several intermediate stages); 4) determine traverses in the array epsilon; 5) plot these traverses by a printer; 6) simplify plots of these traverses by the PLOTEASY-system by creating input data blocks for this system. The main application of COMPAR is given (so far) by the comparison of two- and three-dimensional multigroup neutron flux-fields. (orig.) [de

  8. A comparative study on energetic, exergetic and environmental performance assessments of novel M-Cycle based air coolers for buildings

    International Nuclear Information System (INIS)

    Caliskan, Hakan; Dincer, Ibrahim; Hepbasli, Arif

    2012-01-01

    Highlights: ► Applying exergy, environment and sustainability analyses to the three (novel M-Cycle based) air coolers. ► Assessing energy and exergy efficiencies, environmental impact and sustainability. ► Proposing System II (using PV-based electricity) as the most environmentally friendly air cooler. ► Proposing System III (using coal-based electricity) as the most efficient air cooler. - Abstract: In this study, three various novel air coolers based on M-Cycle are evaluated using energy and exergy analyses based efficiency assessments along with environmental impact and sustainability parameters. The M-Cycle systems are considered to cool a building room air while their inlet air parameters are same, but outlet cooled air parameters are different. Systems I and III draw electricity directly taken from an electric grid in the building while System II, which is stand alone system, produces and draws electricity from its solar PV panels. In the energy analysis, wet bulb effectiveness, cooling capacity, Coefficient of Performance (energetic COP) and Primary Energy Ratio (PER) are found. In the exergy analysis, exergy input and output rates, exergy loss rate, exergy destruction rate, Exergetic Coefficient of Performance (COP ex ), Primary Exergy Ratio (PE x R) and exergy efficiency are obtained for six different dead state temperatures changing between 10 °C and 35 °C. Also, sustainability assessments of the systems are obtained using sustainability index (SI) tool for these various dead state temperatures. Finally, environmental assessments of the systems are calculated from their greenhouse gas (GHG) emissions (gCO 2 /kW h) due to their electricity consumptions. Maximum exergy efficiencies and sustainability assessments are found to be 35.13% and 1.5415 for System III and 34.94% and 1.5372 for System II, respectively. GHG emissions of the systems are calculated to be 2119.68 gCO 2 /day, 153.6 gCO 2 /day and 3840 gCO 2 /day for Systems I, II and III

  9. Intermittency and transition to chaos in the cubical lid-driven cavity flow

    Energy Technology Data Exchange (ETDEWEB)

    Loiseau, J-Ch [Department of Mechanics, Royal Institute of Technology (KTH), SE-100 44 Stockholm (Sweden); Robinet, J-Ch [Laboratoire DynFluid, Arts et Métiers ParisTech, F-75013 Paris (France); Leriche, E, E-mail: loiseau@mech.kth.se [Laboratoire de Mécanique de Lille, Université Lille 1, F-59655 Villeneuve d’Ascq (France)

    2016-12-15

    Transition from steady state to intermittent chaos in the cubical lid-driven cavity flow is investigated numerically. Fully three-dimensional stability analyses have revealed that the flow experiences an Andronov–Poincaré–Hopf bifurcation at a critical Reynolds number Re {sub c} = 1914. As for the 2D-periodic lid-driven cavity flows, the unstable mode originates from a centrifugal instability of the primary vortex core. A Reynolds–Orr analysis reveals that the unstable perturbation relies on a combination of the lift-up and anti lift-up mechanisms to extract its energy from the base flow. Once linearly unstable, direct numerical simulations show that the flow is driven toward a primary limit cycle before eventually exhibiting intermittent chaotic dynamics. Though only one eigenpair of the linearized Navier–Stokes operator is unstable, the dynamics during the intermittencies are surprisingly well characterized by one of the stable eigenpairs. (paper)

  10. Comparative assessment and management of the health and environmental impacts of energy systems. General framework and preliminary results for the nuclear fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    Rostron, W; Schneider, T; Thieme, M; Dreicer, M

    1992-06-01

    The comparison of the effects of electricity producing systems is of growing importance in decision-making processes for energy planning. This report documents the preliminary results of a project for the CEC-DG XII Radiation Protection Programme on the comparative assessment and management of the health and environmental impacts of energy systems. The work reported in this document has also been supported by EDF - Mission Environnement. In order to profit from the comparative studies already existing, some of the most important ones were surveyed. The aim of these past energy comparison studies was mainly to obtain a global measure of the risks associated with an energy cycle, with a view to ranking the various electricity production systems; but this is now recognised as merely an academic exercise, with a limited impact in decision-making. For energy planning the development of a multi-dimensional approach seems more suitable, as this allows the different types of indicators and measures needed to assess the risks of different energy cycles to be compared. From the past studies it has been seen that health indicators are generally well established, but a weakness is noted with respect to indicators of environmental impacts. This remains a difficult subject, and until such indicators are established, surrogates like concentrations in the environment will have to be used, or qualitative comparisons must suffice. This report presents a general framework allowing for consistent comparisons between different energy systems. The key issues discussed are: assessment by fuel cycle, consideration of the dimensions of time and space, the impact pathway approach for assessing risk, and coherent indicators that can be used to measure the impacts. First results are presented for four activities of the nuclear fuel cycle according to the approach developed: (1) the construction and dismantling of a 900 MWe pressurized water reactor, (2) the transportation of materials between

  11. Comparative anatomy and histology of developmental and parasitic stages in the life cycle of the lined sea anemone Edwardsiella lineata.

    Science.gov (United States)

    Reitzel, Adam M; Daly, Marymegan; Sullivan, James C; Finnerty, John R

    2009-02-01

    The evolution of parasitism is often accompanied by profound changes to the developmental program. However, relatively few studies have directly examined the developmental evolution of parasitic species from free-living ancestors. The lined sea anemone Edwardsiella lineata is a relatively recently evolved parasite for which closely related free-living outgroups are known, including the starlet sea anemone Nematostella vectensis. The larva of E. lineata parasitizes the ctenophore Mnemiopsis leidyi, and, once embedded in its host, the anemone assumes a novel vermiform body plan. That we might begin to understand how the developmental program of this species has been transformed during the evolution of parasitism, we characterized the gross anatomy, histology, and cnidom of the parasitic stage, post-parasitic larval stage, and adult stage of the E. lineata life cycle. The distinct parasitic stage of the life cycle differs from the post-parasitic larva with respect to overall shape, external ciliation, cnida frequency, and tissue architecture. The parasitic stage and planula both contain holotrichs, a type of cnida not previously reported in Edwardsiidae. The internal morphology of the post-parasitic planula is extremely similar to the adult morphology, with a complete set of mesenterial tissue and musculature despite this stage having little external differentiation. Finally, we observed 2 previously undocumented aspects of asexual reproduction in E. lineata: (1) the parasitic stage undergoes transverse fission via physal pinching, the first report of asexual reproduction in a pre-adult stage in the Edwardsiidae; and (2) the juvenile polyp undergoes transverse fission via polarity reversal, the first time this form of fission has been reported in E. lineata.

  12. Enhanced muscle blood flow with intermittent pneumatic compression of the lower leg during plantar flexion exercise and recovery.

    Science.gov (United States)

    Zuj, K A; Prince, C N; Hughson, R L; Peterson, S D

    2018-02-01

    This study tested the hypothesis that intermittent compression of the lower limb would increase blood flow during exercise and postexercise recovery. Data were collected from 12 healthy individuals (8 men) who performed 3 min of standing plantar flexion exercise. The following three conditions were tested: no applied compression (NoComp), compression during the exercise period only (ExComp), and compression during 2 min of standing postexercise recovery. Doppler ultrasound was used to determine superficial femoral artery (SFA) blood flow responses. Mean arterial pressure (MAP) and cardiac stroke volume (SV) were assessed using finger photoplethysmography, with vascular conductance (VC) calculated as VC = SFA flow/MAP. Compared with the NoComp condition, compression resulted in increased MAP during exercise [+3.5 ± 4.1 mmHg (mean ± SD)] but not during postexercise recovery (+1.6 ± 5.9 mmHg). SV increased with compression during both exercise (+4.8 ± 5.1 ml) and recovery (+8.0 ± 6.6 ml) compared with NoComp. There was a greater increase in SFA flow with compression during exercise (+52.1 ± 57.2 ml/min) and during recovery (+58.6 ± 56.7 ml/min). VC immediately following exercise was also significantly greater in the ExComp condition compared with the NoComp condition (+0.57 ± 0.42 ml·min -1 ·mmHg -1 ), suggesting the observed increase in blood flow during exercise was in part because of changes in VC. Results from this study support the hypothesis that intermittent compression applied during exercise and recovery from exercise results in increased limb blood flow, potentially contributing to changes in exercise performance and recovery. NEW & NOTEWORTHY Blood flow to working skeletal muscle is achieved in part through the rhythmic actions of the skeletal muscle pump. This study demonstrated that the application of intermittent pneumatic compression during the diastolic phase of the cardiac cycle, to mimic the mechanical

  13. The Acute Effects of Intermittent Light Exposure in the Evening on Alertness and Subsequent Sleep Architecture.

    Science.gov (United States)

    Yang, Minqi; Ma, Ning; Zhu, Yingying; Su, Ying-Chu; Chen, Qingwei; Hsiao, Fan-Chi; Ji, Yanran; Yang, Chien-Ming; Zhou, Guofu

    2018-03-15

    Exposure to bright light is typically intermittent in our daily life. However, the acute effects of intermittent light on alertness and sleep have seldom been explored. To investigate this issue, we employed within-subject design and compared the effects of three light conditions: intermittent bright light (30-min pulse of blue-enriched bright light (~1000 lux, ~6000 K) alternating with 30-min dim normal light (~5 lux, ~3600 K) three times); continuous bright light; and continuous dim light on subjective and objective alertness and subsequent sleep structure. Each light exposure was conducted during the three hours before bedtime. Fifteen healthy volunteers (20 ± 3.4 years; seven males) were scheduled to stay in the sleep laboratory for four separated nights (one for adaptation and the others for the light exposures) with a period of at least one week between nights. The results showed that when compared with dim light, both intermittent light and continuous bright light significantly increased subjective alertness and decreased sleep efficiency (SE) and total sleep time (TST). Intermittent light significantly increased objective alertness than dim light did during the second half of the light-exposure period. Our results suggested that intermittent light was as effective as continuous bright light in their acute effects in enhancing subjective and objective alertness and in negatively impacting subsequent sleep.

  14. The Acute Effects of Intermittent Light Exposure in the Evening on Alertness and Subsequent Sleep Architecture

    Directory of Open Access Journals (Sweden)

    Minqi Yang

    2018-03-01

    Full Text Available Exposure to bright light is typically intermittent in our daily life. However, the acute effects of intermittent light on alertness and sleep have seldom been explored. To investigate this issue, we employed within-subject design and compared the effects of three light conditions: intermittent bright light (30-min pulse of blue-enriched bright light (~1000 lux, ~6000 K alternating with 30-min dim normal light (~5 lux, ~3600 K three times; continuous bright light; and continuous dim light on subjective and objective alertness and subsequent sleep structure. Each light exposure was conducted during the three hours before bedtime. Fifteen healthy volunteers (20 ± 3.4 years; seven males were scheduled to stay in the sleep laboratory for four separated nights (one for adaptation and the others for the light exposures with a period of at least one week between nights. The results showed that when compared with dim light, both intermittent light and continuous bright light significantly increased subjective alertness and decreased sleep efficiency (SE and total sleep time (TST. Intermittent light significantly increased objective alertness than dim light did during the second half of the light-exposure period. Our results suggested that intermittent light was as effective as continuous bright light in their acute effects in enhancing subjective and objective alertness and in negatively impacting subsequent sleep.

  15. Three hours of intermittent hypoxia increases circulating glucose levels in healthy adults.

    Science.gov (United States)

    Newhouse, Lauren P; Joyner, Michael J; Curry, Timothy B; Laurenti, Marcello C; Man, Chiara Dalla; Cobelli, Claudio; Vella, Adrian; Limberg, Jacqueline K

    2017-01-01

    An independent association exists between sleep apnea and diabetes. Animal models suggest exposure to intermittent hypoxia, a consequence of sleep apnea, results in altered glucose metabolism and fasting hyperglycemia. However, it is unknown if acute exposure to intermittent hypoxia increases glucose concentrations in nondiabetic humans. We hypothesized plasma glucose would be increased from baseline following 3 h of intermittent hypoxia in healthy humans independent of any effect on insulin sensitivity. Eight (7M/1F, 21-34 years) healthy subjects completed two study visits randomized to 3 h of intermittent hypoxia or continuous normoxia, followed by an oral glucose tolerance test. Intermittent hypoxia consisted of 25 hypoxic events per hour where oxygen saturation (SpO 2 ) was significantly reduced (Normoxia: 97 ± 1%, Hypoxia: 90 ± 2%, P  0.05). In contrast, circulating glucose concentrations were increased after 3 h of intermittent hypoxia when compared to baseline (5.0 ± 0.2 vs. 5.3 ± 0.2 mmol/L, P = 0.01). There were no detectable changes in insulin sensitivity following intermittent hypoxia when compared to continuous normoxia, as assessed by the oral glucose tolerance test (P > 0.05). Circulating glucose is increased after 3 h of intermittent hypoxia in healthy humans, independent of any lasting changes in insulin sensitivity. These novel findings could explain, in part, the high prevalence of diabetes in patients with sleep apnea and warrant future studies to identify underlying mechanisms. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  16. Repetitive stimulation of autophagy-lysosome machinery by intermittent fasting preconditions the myocardium to ischemia-reperfusion injury.

    Science.gov (United States)

    Godar, Rebecca J; Ma, Xiucui; Liu, Haiyan; Murphy, John T; Weinheimer, Carla J; Kovacs, Attila; Crosby, Seth D; Saftig, Paul; Diwan, Abhinav

    2015-01-01

    Autophagy, a lysosomal degradative pathway, is potently stimulated in the myocardium by fasting and is essential for maintaining cardiac function during prolonged starvation. We tested the hypothesis that intermittent fasting protects against myocardial ischemia-reperfusion injury via transcriptional stimulation of the autophagy-lysosome machinery. Adult C57BL/6 mice subjected to 24-h periods of fasting, every other day, for 6 wk were protected from in-vivo ischemia-reperfusion injury on a fed day, with marked reduction in infarct size in both sexes as compared with nonfasted controls. This protection was lost in mice heterozygous null for Lamp2 (coding for lysosomal-associated membrane protein 2), which demonstrate impaired autophagy in response to fasting with accumulation of autophagosomes and SQSTM1, an autophagy substrate, in the heart. In lamp2 null mice, intermittent fasting provoked progressive left ventricular dilation, systolic dysfunction and hypertrophy; worsening cardiomyocyte autophagosome accumulation and lack of protection to ischemia-reperfusion injury, suggesting that intact autophagy-lysosome machinery is essential for myocardial homeostasis during intermittent fasting and consequent ischemic cardioprotection. Fasting and refeeding cycles resulted in transcriptional induction followed by downregulation of autophagy-lysosome genes in the myocardium. This was coupled with fasting-induced nuclear translocation of TFEB (transcription factor EB), a master regulator of autophagy-lysosome machinery; followed by rapid decline in nuclear TFEB levels with refeeding. Endogenous TFEB was essential for attenuation of hypoxia-reoxygenation-induced cell death by repetitive starvation, in neonatal rat cardiomyocytes, in-vitro. Taken together, these data suggest that TFEB-mediated transcriptional priming of the autophagy-lysosome machinery mediates the beneficial effects of fasting-induced autophagy in myocardial ischemia-reperfusion injury.

  17. Repetitive stimulation of autophagy-lysosome machinery by intermittent fasting preconditions the myocardium to ischemia-reperfusion injury

    Science.gov (United States)

    Godar, Rebecca J; Ma, Xiucui; Liu, Haiyan; Murphy, John T; Weinheimer, Carla J; Kovacs, Attila; Crosby, Seth D; Saftig, Paul; Diwan, Abhinav

    2015-01-01

    Autophagy, a lysosomal degradative pathway, is potently stimulated in the myocardium by fasting and is essential for maintaining cardiac function during prolonged starvation. We tested the hypothesis that intermittent fasting protects against myocardial ischemia-reperfusion injury via transcriptional stimulation of the autophagy-lysosome machinery. Adult C57BL/6 mice subjected to 24-h periods of fasting, every other day, for 6 wk were protected from in-vivo ischemia-reperfusion injury on a fed day, with marked reduction in infarct size in both sexes as compared with nonfasted controls. This protection was lost in mice heterozygous null for Lamp2 (coding for lysosomal-associated membrane protein 2), which demonstrate impaired autophagy in response to fasting with accumulation of autophagosomes and SQSTM1, an autophagy substrate, in the heart. In lamp2 null mice, intermittent fasting provoked progressive left ventricular dilation, systolic dysfunction and hypertrophy; worsening cardiomyocyte autophagosome accumulation and lack of protection to ischemia-reperfusion injury, suggesting that intact autophagy-lysosome machinery is essential for myocardial homeostasis during intermittent fasting and consequent ischemic cardioprotection. Fasting and refeeding cycles resulted in transcriptional induction followed by downregulation of autophagy-lysosome genes in the myocardium. This was coupled with fasting-induced nuclear translocation of TFEB (transcription factor EB), a master regulator of autophagy-lysosome machinery; followed by rapid decline in nuclear TFEB levels with refeeding. Endogenous TFEB was essential for attenuation of hypoxia-reoxygenation-induced cell death by repetitive starvation, in neonatal rat cardiomyocytes, in-vitro. Taken together, these data suggest that TFEB-mediated transcriptional priming of the autophagy-lysosome machinery mediates the beneficial effects of fasting-induced autophagy in myocardial ischemia-reperfusion injury. PMID:26103523

  18. Chronic intermittent hypoxia exerts CNS region-specific effects on rat microglial inflammatory and TLR4 gene expression.

    Directory of Open Access Journals (Sweden)

    Stephanie M C Smith

    Full Text Available Intermittent hypoxia (IH during sleep is a hallmark of sleep apnea, causing significant neuronal apoptosis, and cognitive and behavioral deficits in CNS regions underlying memory processing and executive functions. IH-induced neuroinflammation is thought to contribute to cognitive deficits after IH. In the present studies, we tested the hypothesis that IH would differentially induce inflammatory factor gene expression in microglia in a CNS region-dependent manner, and that the effects of IH would differ temporally. To test this hypothesis, adult rats were exposed to intermittent hypoxia (2 min intervals of 10.5% O2 for 8 hours/day during their respective sleep cycles for 1, 3 or 14 days. Cortex, medulla and spinal cord tissues were dissected, microglia were immunomagnetically isolated and mRNA levels of the inflammatory genes iNOS, COX-2, TNFα, IL-1β and IL-6 and the innate immune receptor TLR4 were compared to levels in normoxia. Inflammatory gene expression was also assessed in tissue homogenates (containing all CNS cells. We found that microglia from different CNS regions responded to IH differently. Cortical microglia had longer lasting inflammatory gene expression whereas spinal microglial gene expression was rapid and transient. We also observed that inflammatory gene expression in microglia frequently differed from that in tissue homogenates from the same region, indicating that cells other than microglia also contribute to IH-induced neuroinflammation. Lastly, microglial TLR4 mRNA levels were strongly upregulated by IH in a region- and time-dependent manner, and the increase in TLR4 expression appeared to coincide with timing of peak inflammatory gene expression, suggesting that TLR4 may play a role in IH-induced neuroinflammation. Together, these data indicate that microglial-specific neuroinflammation may play distinct roles in the effects of intermittent hypoxia in different CNS regions.

  19. Effects of intermittent fasting and chronic swimming exercise on body composition and lipid metabolism.

    Science.gov (United States)

    Moraes, Ruan Carlos Macedo de; Portari, Guilherme Vannucchi; Ferraz, Alex Soares Marreiros; da Silva, Tiago Eugênio Oliveira; Marocolo, Moacir

    2017-12-01

    Intermittent fasting protocol (IFP) has been suggested as a strategy to change body metabolism and improve health. The effects of IFP seem to be similar to aerobic exercise, having a hormetic adaptation according to intensity and frequency. However, the effects of combining both interventions are still unknown. Therefore, the aim of the present study was to evaluate the effects of IFP with and without endurance-exercise training on body composition, food behavior, and lipid metabolism. Twenty-week-old Wistar rats were kept under an inverted circadian cycle of 12 h with water ad libitum and assigned to 4 different groups: control group (ad libitum feeding and sedentary), exercise group (ad libitum feeding and endurance training), intermittent fasting group (IF; intermittent fasting and sedentary), and intermittent fasting and exercise group (IFEX; intermittent fasting and endurance training). After 6 weeks, the body weight of IF and IFEX animals decreased without changes in food consumption. Yet, the body composition between the 2 groups was different, with the IFEX animals containing higher total protein and lower total fat content than the IF animals. The IFEX group also showed increases in total high-density lipoprotein cholesterol and increased intramuscular lipid content. The amount of brown adipose tissue was higher in IF and IFEX groups; however, the IFEX group showed higher expression levels of uncoupling protein 1 in this tissue, indicating a greater thermogenesis. The IFP combined with endurance training is an efficient method for decreasing body mass and altering fat metabolism, without inflicting losses in protein content.

  20. Sprint vs. intermittent training in young female basketball players.

    Science.gov (United States)

    Attene, G; Pizzolato, F; Calcagno, G; Ibba, G; Pinna, M; Salernitano, G; Padulo, J

    2014-04-01

    This study aimed at comparing the effects of intermittent and repeated sprint ability training on physiological variables. Sixteen young female basketball players were randomly allocated to intermittent training (IT=8) or repeated sprint ability training (RST=8) groups. The following outcomes were measured at baseline and after 6 weeks of training: Yo-Yo intermittent recovery (Yo-Yo) and repeated sprint ability (RSA) tests. For all the variables investigated the effect of training type showed a different trend respect at current knowledge. In the RSA, best time (BT) was a significant main effect of training time (pre- vs. post-) (Ptraining type/time (P=0.03). The RST showed a decrease in BT of 3.1% (P=0.005) while the IT showed a decrease of 6.2% (Ptraining methods used in this study can be an effective training strategy for inducing anaerobic and basketball-specific training schedules. Besides, even when IT training is not done at very high speed, it can increase the maximum speed of the RSA.

  1. Solid-state fermentation and composting as alternatives to treat hair waste: A life-cycle assessment comparative approach.

    Science.gov (United States)

    Catalán, Eva; Komilis, Dimitrios; Sánchez, Antoni

    2017-07-01

    One of the wastes associated with leather production in tannery industries is the hair residue generated during the dehairing process. Hair wastes are mainly dumped or managed through composting but recent studies propose the treatment of hair wastes through solid-state fermentation (SSF) to obtain proteases and compost. These enzymes are suitable for its use in an enzymatic dehairing process, as an alternative to the current chemical dehairing process. In the present work, two different scenarios for the valorization of the hair waste are proposed and assessed by means of life-cycle assessment: composting and SSF for protease production. Detailed data on hair waste composting and on SSF protease production are gathered from previous studies performed by our research group and from a literature survey. Background inventory data are mainly based on Ecoinvent version 3 from software SimaPro® 8. The main aim of this study was to identify which process results in the highest environmental impact. The SSF process was found to have lower environmental impacts than composting, due to the fact that the enzyme use in the dehairing process prevents the use of chemicals traditionally used in the dehairing process. This permits to reformulate an industrial process from the classical approach of waste management to a novel alternative based on circular economy.

  2. Intermittent ephemeral river-breaching

    Science.gov (United States)

    Reniers, A. J.; MacMahan, J. H.; Gallagher, E. L.; Shanks, A.; Morgan, S.; Jarvis, M.; Thornton, E. B.; Brown, J.; Fujimura, A.

    2012-12-01

    In the summer of 2011 we performed a field experiment in Carmel River State Beach, CA, at a time when the intermittent natural breaching of the ephemeral Carmel River occurred due to an unusually rainy period prior to the experiment associated with El Nino. At this time the river would fill the lagoon over the period of a number of days after which a breach would occur. This allowed us to document a number of breaches with unique pre- and post-breach topographic surveys, accompanying ocean and lagoon water elevations as well as extremely high flow (4m/s) velocities in the river mouth during the breaching event. The topographic surveys were obtained with a GPS-equipped backpack mounted on a walking human and show the evolution of the river breaching with a gradually widening and deepening river channel that cuts through the pre-existing beach and berm. The beach face is qualified as a steep with an average beach slope of 1:10 with significant reflection of the incident waves (MacMahan et al., 2012). The wave directions are generally shore normal as the waves refract over the deep canyon that is located offshore of the beach. The tide is mixed semi-diurnal with a range on the order of one meter. Breaching typically occurred during the low-low tide. Grain size is highly variable along the beach with layers of alternating fine and coarse material that could clearly be observed as the river exit channel was cutting through the beach. Large rocky outcroppings buried under the beach sand are also present along certain stretches of the beach controlling the depth of the breaching channel. The changes in the water level measured within the lagoon and the ocean side allows for an estimate of the volume flux associated with the breach as function of morphology, tidal elevation and wave conditions as well as an assessment of the conditions and mechanisms of breach closure, which occurred on the time scale of O(0.5 days). Exploratory model simulations will be presented at the

  3. Coherent Structures and Intermittency in Plasma Turbulence

    International Nuclear Information System (INIS)

    Das, Amita; Kaw, Predhiman; Sen, Abhijit

    2008-01-01

    The paper discusses some fundamental issues related to the phenomenon of intermittency in plasma turbulence with particular reference to experimental observations in fusion devices. Intermittency is typically associated with the presence of coherent structures in turbulence. Since coherent structures can play an important role in governing the transport properties of a system they have received a great deal of attention in fusion research. We review some of the experimental measurements and numerical simulation studies on the presence and formation of coherent structures in plasmas and discuss their relevance to intermittency. Intermittency, as widely discussed in the context of neutral fluid turbulence, implies multiscaling behaviour in contrast to self-similar scaling patterns observed in self organized criticality (SOC) phenomenon. The experimental evidence from plasma turbulence measurements reveal a mixed picture--while some observations support the SOC model description others indicate the presence of multiscaling behaviour. We discuss these results in the light of our present understanding of plasma turbulence and in terms of certain unique aspects of intermittency as revealed by fluid models of plasmas.

  4. Intermittent pneumatic compression of legs increases microcirculation in distant skeletal muscle.

    Science.gov (United States)

    Liu, K; Chen, L E; Seaber, A V; Johnson, G W; Urbaniak, J R

    1999-01-01

    Intermittent pneumatic compression has been established as a method of clinically preventing deep vein thrombosis, but the mechanism has not been documented. This study observed the effects of intermittent pneumatic compression of legs on the microcirculation of distant skeletal muscle. The cremaster muscles of 80 male rats were exposed, a specially designed intermittent pneumatic-compression device was applied to both legs for 60 minutes, and the microcirculation of the muscles was assessed by measurement of the vessel diameter in three categories (10-20, 21-40, and 41-70 microm) for 120 minutes. The results showed significant vasodilation in arterial and venous vessels during the application of intermittent pneumatic compression, which disappeared after termination of the compression. The vasodilation reached a maximum 30 minutes after initiation of the compression and could be completely blocked by an inhibitor of nitric oxide synthase, NG-monomethyl-L-arginine (10 micromol/min). A 120-minute infusion of NG-monomethyl-L-arginine, beginning coincident with 60 minutes of intermittent pneumatic compression, resulted in a significant decrease in arterial diameter that remained at almost the same level after termination of the compression. The magnitude of the decrease in diameter in the group treated with intermittent pneumatic compression and NG-monomethyl-L-arginine was comparable with that in the group treated with NG-monomethyl-L-arginine alone. The results imply that the production of nitric oxide is involved in the positive influence of intermittent pneumatic compression on circulation. It is postulated that the rapid increase in venous velocity induced by intermittent pneumatic compression produces strong shear stress on the vascular endothelium, which stimulates an increased release of nitric oxide and thereby causes systemic vasodilation.

  5. Nitrogen removal in the bioreactor landfill system with intermittent aeration at the top of landfilled waste

    International Nuclear Information System (INIS)

    He Ruo; Shen Dongsheng

    2006-01-01

    High ammonia concentration of recycled landfill leachate makes it very difficult to treat. In this work, a vertical aerobic/anoxic/anaerobic lab-scale bioreactor landfill system, which was constructed by intermittent aeration at the top of landfilled waste, as a bioreactor for in situ nitrogen removal was investigated during waste stabilization. Intermittent aeration at the top of landfilled waste might stimulate the growth of nitrifying bacteria and denitrifying bacteria in the top and middle layers of waste. The nitrifying bacteria population for the landfill bioreactor with intermittent aeration system reached between10 6 and 10 8 cells/dry g waste, although it decreased 2 orders of magnitude on day 30, due to the inhibitory effect of the acid environment and high organic matter in the landfilled waste. The denitrifying bacteria population increased by between 4 and 13 orders of magnitude compared with conventional anaerobic landfilled waste layers. Leachate NO 3 - -N concentration was very low in both two experimental landfill reactors. After 105 days operation, leachate NH 4 + -N and TN concentrations for the landfill reactor with intermittent aeration system dropped to 186 and 289 mg/l, respectively, while they were still kept above 1000 mg/l for the landfill reactor without intermittent aerobic system. In addition, there is an increase in the rate of waste stabilization as well as an increase of 12% in the total waste settlement for the landfill reactor with intermittent aeration system

  6. Comparative life cycle assessment of biogas plant configurations for a demand oriented biogas supply for flexible power generation.

    Science.gov (United States)

    Hahn, Henning; Hartmann, Kilian; Bühle, Lutz; Wachendorf, Michael

    2015-03-01

    The environmental performance of biogas plant configurations for a demand - oriented biogas supply for flexible power generation is comparatively assessed in this study. Those configurations indicate an increased energy demand to operate the operational enhancements compared to conventional biogas plants supplying biogas for baseload power generation. However, findings show that in contrast to an alternative supply of power generators with natural gas, biogas supplied on demand by adapted biogas plant configurations saves greenhouse gas emissions by 54-65 g CO(2-eq) MJ(-1) and primary energy by about 1.17 MJ MJ(-1). In this regard, configurations with flexible biogas production profit from reduced biogas storage requirements and achieve higher savings compared to configurations with continuous biogas production. Using thicker biogas storage sheeting material reduces the methane permeability of up to 6m(3) d(-1) which equals a reduction of 8% of the configuration's total methane emissions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Total intermittent Pringle maneuver during liver resection can induce intestinal epithelial cell damage and endotoxemia.

    Directory of Open Access Journals (Sweden)

    Simon A W G Dello

    Full Text Available OBJECTIVES: The intermittent Pringle maneuver (IPM is frequently applied to minimize blood loss during liver transection. Clamping the hepatoduodenal ligament blocks the hepatic inflow, which leads to a non circulating (hepatosplanchnic outflow. Also, IPM blocks the mesenteric venous drainage (as well as the splenic drainage with raising pressure in the microvascular network of the intestinal structures. It is unknown whether the IPM is harmful to the gut. The aim was to investigate intestinal epithelial cell damage reflected by circulating intestinal fatty acid binding protein levels (I-FABP in patients undergoing liver resection with IPM. METHODS: Patients who underwent liver surgery received total IPM (total-IPM or selective IPM (sel-IPM. A selective IPM was performed by selectively clamping the right portal pedicle. Patients without IPM served as controls (no-IPM. Arterial blood samples were taken immediately after incision, ischemia and reperfusion of the liver, transection, 8 hours after start of surgery and on the first post-operative day. RESULTS: 24 patients (13 males were included. 7 patients received cycles of 15 minutes and 5 patients received cycles of 30 minutes of hepatic inflow occlusion. 6 patients received cycles of 15 minutes selective hepatic occlusion and 6 patients underwent surgery without inflow occlusion. Application of total-IPM resulted in a significant increase in I-FABP 8 hours after start of surgery compared to baseline (p<0.005. In the no-IPM group and sel-IPM group no significant increase in I-FABP at any time point compared to baseline was observed. CONCLUSION: Total-IPM in patients undergoing liver resection is associated with a substantial increase in arterial I-FABP, pointing to intestinal epithelial injury during liver surgery. TRIAL REGISTRATION: ClinicalTrials.gov NCT01099475.

  8. Laboratory investigation on effects of flood intermittency on river delta dynamics

    Science.gov (United States)

    Miller, K. L.; Kim, W.

    2015-12-01

    In order to simplify the complex hydrological variability of flow conditions, experiments modeling delta evolution are often conducted using a representative "channel-forming" flood flow and then relate results to field settings using an intermittency factor, defined as the fraction of total time at flood conditions. Although this intermittency factor makes it easier to investigate how variables, such as relative base level and/or sediment supply, affect delta dynamics, little is known about how this generalization to a single flow condition affects delta processes. We conducted a set of laboratory experiments with periodic flow conditions to determine the effects of intermittent discharges on delta evolution. During the experiment, flood with a set water discharge and sediment supply, cycles between periods of normal flow where the water flux is halved and the sediment discharge is turned off. For each run, the magnitude of the flood is held constant, but the duration is assigned differently, thus varying the intermittency between 1 and 0.2. We find that as the intermittency factor decreases (duration of each flood period decreases), the delta topset has a larger, more elongated area with a shallower slope as a result of reworking on the delta topset during normal flow conditions. During periods of normal flow, the system adjusts towards a new equilibrium state that then in turn acts as the initial condition for the subsequent flood period. Furthermore, the natural delta avulsion cycle becomes obscured by the flood cycles as the flood duration becomes shorter than the autogenic behavior. These results suggest that the adjustment timescale for differing flow conditions is a factor in determining the overall shape of the delta and behavior of the fluviodeltaic channels. We conclude, periods of normal flow when topset sediment is reworked, may be just as important to delta dynamics as periods of flood when sediment is supplied to the system.

  9. Comparing life cycle energy and GHG emissions of bio-based PET, recycled PET, PLA and man-made cellulosics

    NARCIS (Netherlands)

    Shen, L.; Worrell, E.; Patel, M.K.

    2012-01-01

    The purpose of this paper is to review the environmental profiles of petrochemical PET, (partially) bio-based PET, recycled PET, and recycled (partially) bio-based PET, and compare them with other bio-based materials, namely PLA (polylactic acid, a bio-based polyester) and man-made cellulose

  10. Dynamic analysis of the CTAR (constant temperature adsorption refrigeration) cycle

    International Nuclear Information System (INIS)

    Hassan, H.Z.; Mohamad, A.A.; Al-Ansary, H.A.; Alyousef, Y.M.

    2014-01-01

    The basic SAR (solar-driven adsorption refrigeration) machine is an intermittent cold production system. Recently, the CO-SAR (continuous operation solar-powered adsorption refrigeration) system is developed. The CO-SAR machine is based on the theoretical CTAR (constant temperature adsorption refrigeration) cycle in which the adsorption process takes place at a constant temperature that equals the ambient temperature. Practically, there should be a temperature gradient between the adsorption bed and the surrounding atmosphere to provide a driving potential for heat transfer. In the present study, the dynamic analysis of the CTAR cycle is developed. This analysis provides a comparison between the theoretical and the dynamic operation of the CTAR cycle. The developed dynamic model is based on the D-A adsorption equilibrium equation and the energy and mass balances in the adsorption reactor. Results obtained from the present work demonstrate that, the idealization of the constant temperature adsorption process in the theoretical CTAR cycle is not far from the real situation and can be approached. Furthermore, enhancing the heat transfer between the adsorption bed and the ambient during the bed pre-cooling process helps accelerating the heat rejection process from the adsorption reactor and therefore approaching the isothermal process. - Highlights: • The dynamic analysis of the CTAR (constant temperature adsorption refrigeration) cycle is developed. • The CTAR theoretical and dynamic cycles are compared. • The dynamic cycle approaches the ideal one by enhancing the bed precooling

  11. Intermittent episodes of bright light suppress myopia in the chicken more than continuous bright light.

    Directory of Open Access Journals (Sweden)

    Weizhong Lan

    Full Text Available PURPOSE: Bright light has been shown a powerful inhibitor of myopia development in animal models. We studied which temporal patterns of bright light are the most potent in suppressing deprivation myopia in chickens. METHODS: Eight-day-old chickens wore diffusers over one eye to induce deprivation myopia. A reference group (n = 8 was kept under office-like illuminance (500 lux at a 10:14 light:dark cycle. Episodes of bright light (15 000 lux were super-imposed on this background as follows. Paradigm I: exposure to constant bright light for either 1 hour (n = 5, 2 hours (n = 5, 5 hours (n = 4 or 10 hours (n = 4. Paradigm II: exposure to repeated cycles of bright light with 50% duty cycle and either 60 minutes (n = 7, 30 minutes (n = 8, 15 minutes (n = 6, 7 minutes (n = 7 or 1 minute (n = 7 periods, provided for 10 hours. Refraction and axial length were measured prior to and immediately after the 5-day experiment. Relative changes were analyzed by paired t-tests, and differences among groups were tested by one-way ANOVA. RESULTS: Compared with the reference group, exposure to continuous bright light for 1 or 2 hours every day had no significant protective effect against deprivation myopia. Inhibition of myopia became significant after 5 hours of bright light exposure but extending the duration to 10 hours did not offer an additional benefit. In comparison, repeated cycles of 1:1 or 7:7 minutes of bright light enhanced the protective effect against myopia and could fully suppress its development. CONCLUSIONS: The protective effect of bright light depends on the exposure duration and, to the intermittent form, the frequency cycle. Compared to the saturation effect of continuous bright light, low frequency cycles of bright light (1:1 min provided the strongest inhibition effect. However, our quantitative results probably might not be directly translated into humans, but rather need further amendments in clinical studies.

  12. Shape of power spectrum of intermittent chaos

    International Nuclear Information System (INIS)

    So, B.C.; Mori, H.

    1984-01-01

    Power spectra of intermittent chaos are calculated analytically. It is found that the power spectrum near onset point consists of a large number of Lorentzian lines with two peaks around frequencies ω = 0 and ω = ω 0 , where ω 0 is a fundamental frequency of a periodic orbit before the onset point, and furthermore the envelope of lines around ω = 0 obeys the power law 1/ + ω +2 , whereas the envelope around ω 0 obeys 1/ + ω-ω 0 +4 . The universality of these power law dependence in a certain class of intermittent chaos are clarified from a phenomenological view point. (author)

  13. Does it matter which Life Cycle Assessment (LCA) tool you choose? - a comparative assessment of SimaPro and GaBi

    DEFF Research Database (Denmark)

    Herrmann, Ivan Tengbjerg; Moltesen, Andreas

    2015-01-01

    SimaPro and GaBi are the leading software tools used for life cycle assessments. Assessing product systems applying the exact same unit process foundation would be expected to yield comparable result sets with either tool. The software performances are compared based on a random sample of 100 unit...... of these differences are so large that they could influence the conclusions. For some of the 100 unit processes, six elementary flows were inventoried differently in SimaPro and GaBi, with an extreme maximum comparative ratio of 109. The implementation of the impact assessment methodologies shows notable differences...... processes. The research question investigated here is; can there be a difference between SimaPro and GaBi influencing the results and the decisions based on them? In many cases the results are identical between SimaPro and GaBi or nearly so, but in other cases the results reveal differences. Some...

  14. Glacial cycles

    DEFF Research Database (Denmark)

    Kaufmann, R. K.; Juselius, Katarina

    We use a statistical model, the cointegrated vector autoregressive model, to assess the degree to which variations in Earth's orbit and endogenous climate dynamics can be used to simulate glacial cycles during the late Quaternary (390 kyr-present). To do so, we estimate models of varying complexity...... and compare the accuracy of their in-sample simulations. Results indicate that strong statistical associations between endogenous climate variables are not enough for statistical models to reproduce glacial cycles. Rather, changes in solar insolation associated with changes in Earth's orbit are needed...... to simulate glacial cycles accurately. Also, results suggest that non-linear 10 dynamics, threshold effects, and/or free oscillations may not play an overriding role in glacial cycles....

  15. Comparative analysis of a DI diesel engine fuelled with biodiesel blends during the European MVEG-A cycle: Preliminary study (I)

    Energy Technology Data Exchange (ETDEWEB)

    Lujan, J.M.; Tormos, B.; Salvador, F.J.; Gargar, K. [CMT-Motores Termicos, Universidad Politecnica de Valencia, Valencia (Spain)

    2009-06-15

    The present work consists of introducing the tests and facilities used to perform a comparative analysis of a diesel engine working with different blends of biodiesel fuel during the New European Driving Cycle. Furthermore, as a preliminary study, it was interesting to know the effects of biodiesel fuel on a common-rail high pressure injection system, those more useful in modern light duty diesel engines, as a consequence of its different physicochemical properties compared with conventional diesel fuel. As the real goal of the study is to compare fairly performance and emissions from the engine, it was essential to know any injection effects owed to fuel's own characteristics that finally would affect those parameters that will be evaluated. A complete fuel characterization for diesel and biodiesel fuels, as the EN 590 and the EN 14214 standard specifications, was performed in order to quantify the differences between both fuels. A priori, it could be thought that viscosity and density values will be the most significant parameters capable of altering the injection rate. As positive results, it was obtained that the common-rail high pressure injection system was totally blind in the injection rate measurements, even the significant differences between both fuels, taking into account the counterbalancing effects generated by two parameters mentioned before. The second part of the study deals with engine performance and pollutant emissions on an unmodified common-rail turbocharged diesel engine running with biodiesel fuel blends during the New European Driving Cycle. (author)

  16. To Which Degree Does Sector Specific Standardization Make Life Cycle Assessments Comparable?—The Case of Global Warming Potential of Smartphones

    Directory of Open Access Journals (Sweden)

    Anders S. G. Andrae

    2014-11-01

    Full Text Available Here attributional life cycle assessments (LCAs for the same smartphone model are presented by two different organizations (Orange, OGE and Huawei, HuW and the effect of different modeling approach is analyzed. A difference of around 32% (29.6 kg and 39.2 kg for CO2e baseline scores is found using same study object and sector specific LCA standard, however, different metrics, emission intensities, and LCA software programs. The CO2e difference is reduced to 12% (29.9 kg and 33.5 kg when OGE use HuW metrics for use phase power consumption and total mass, and when HuW use OGE metrics for gold mass and silicon die area. Further, a probability test confirms that present baseline climate change results, for one specific study object modeled with two largely different and independent LCA modeling approaches, are comparable if both use the European Telecommunications Standard Institute (ETSI LCA standard. The general conclusion is that the ETSI LCA standard strongly facilitates comparable CC results for technically comparable smartphone models. Moreover, thanks to the reporting requirements of ETSI LCA standard, a clear understanding of the differences between LCA modeling approaches is obtained. The research also discusses the magnitude of the CO2e reduction potential in the life cycle of smartphones.

  17. Comparative study of fast critical burner reactors and subcritical accelerator driven systems and the impact on transuranics inventory in a regional fuel cycle

    International Nuclear Information System (INIS)

    Romanello, V.; Salvatores, M.; Schwenk-Ferrero, A.; Gabrielli, F.; Maschek, W.; Vezzoni, B.

    2011-01-01

    Research highlights: → Double-strata fuel cycle has a potential to minimize transuranics mass in Europe. → European Minor Actinides legacy can be reduced down to 0 before the end of century. → 40% higher capacity needed to burn MA for fast critical reactor then for EFIT fleet. → Na cooled fast reactor cores with high content of MA and low CR have been assessed. → Fast critical and ADS-EFIT reactors show comparable MA transmutation performance. - Abstract: In the frame of Partitioning and Transmutation (P and T) strategies, many solutions have been proposed in order to burn transuranics (TRU) discharged from conventional thermal reactors in fast reactor systems. This is due to the favourable feature of neutron fission to capture cross section ratio in a fast neutron spectrum for most TRU. However the majority of studies performed use the Accelerator Driven Systems (ADS), due to their potential flexibility to utilize various fuel types, loaded with significant amounts of TRU having very different Minor Actinides (MA) over Pu ratios. Recently the potential of low conversion ratio critical fast reactors has been rediscovered, with very attractive burning capabilities. In the present paper the burning performances of two systems are directly compared: a sodium cooled critical fast reactor with a low conversion ratio, and the European lead cooled subcritical ADS-EFIT reactor loaded with fertile-free fuel. Comparison is done for characteristics of both the intrinsic core and the regional fuel cycle within a European double-strata scenario. Results of the simulations, obtained by use of French COSI6 code, show comparable performance and confirm that in a double strata fuel cycle the same goals could be achieved by deploying dedicated fast critical or ADS-EFIT type reactors. However the critical fast burner reactor fleet requires ∼30-40% higher installed power then the ADS-EFIT one. Therefore full comparative assessment and ranking can be done only by a

  18. Healthcare resource consumption for intermittent urinary catheterisation: cost-effectiveness of hydrophilic catheters and budget impact analyses.

    Science.gov (United States)

    Rognoni, Carla; Tarricone, Rosanna

    2017-01-17

    This study presents a cost-effectiveness analysis comparing hydrophilic coated to uncoated catheters for patients performing urinary intermittent catheterisation. A national budget impact analysis is also included to evaluate the impact of intermittent catheterisation for management of bladder dysfunctions over a period of 5 years. A Markov model (lifetime horizon, 1 year cycle length) was developed to project health outcomes (life years and quality-adjusted life years) and economic consequences related to patients using hydrophilic coated or uncoated catheters. The model was populated with catheter-related clinical efficacy data retrieved from randomised controlled trials and quality-of-life data (utility weights) from the literature. Cost data (EUR, 2015) were estimated on the basis of healthcare resource consumption derived from an e-survey addressed to key opinion leaders in the field. Italian Healthcare Service perspective. Patients with spinal cord injury performing intermittent urinary catheterisation in the home setting. Incremental cost-effectiveness and cost-utility ratios (ICER and ICUR) of hydrophilic coated versus uncoated catheters and associated healthcare budget impact. The base-case ICER and ICUR associated with hydrophilic coated catheters were €20 761 and €24 405, respectively. This implies that hydrophilic coated catheters are likely to be cost-effective in comparison to uncoated ones, as proposed Italian threshold values range between €25 000 and €66 400. Considering a market share at year 5 of 89% hydrophilic catheters and 11% uncoated catheters, the additional cost for Italy is approximately €12 million in the next 5 years (current market share scenario for year 0: 80% hydrophilic catheters and 20% uncoated catheters). Considered over a lifetime, hydrophilic coated catheters are potentially a cost-effective choice in comparison to uncoated ones. These findings can assist policymakers in evaluating intermittent

  19. Comparative study of accelerator driven system (ADS) of different transmutation scenarios for actinides in advanced nuclear fuel cycles

    International Nuclear Information System (INIS)

    Embid-Segura, M.; Gonzalez Romero, M.E.; Perez Parra, A.

    2001-01-01

    The full text follows. In recent years transmutation has raised as a complementary option to solve the problem of the long-lived radioactive waste produced in nuclear power plants. The main advantages expected from transmutation are the reduction in volume of the high level waste and a significant decrease in the long-term radiotoxicity inventory, with a probable impact in the final costs and potential risks of the geological repository. This paper will describe the evaluation of different systems proposed for actinide transmutation, their integration in the waste management process, their viability, performances and limitations. Particular attention is taking of comparing transmutation scenarios where the actinides are transmuted inside fertile (U, Th) or inert matrix. This study has been supported by ENRESA inside the CIEMAT-ENRESA collaboration for the study of long-lived isotope transmutation. (authors)

  20. Which factors make clean intermittent (self) catheterisation successful?

    NARCIS (Netherlands)

    Cobussen-Boekhorst, H.; Beekman, J.; Wijlick, E. van; Schaafstra, J.; Kuppevelt, D. van; Heesakkers, J.P.

    2016-01-01

    AIMS AND OBJECTIVES: To explore which factors determine successful intermittent catheterisation. BACKGROUND: Intermittent catheterisation is a safe, effective treatment and is associated with improved quality of life, although negative issues are reported. Factors which determine adherence are

  1. Intermittent sizing on carbon fiber for composite application

    Energy Technology Data Exchange (ETDEWEB)

    Norris, Jr, Robert E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Paulauskas, Felix L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ozcan, Soydan [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Xiong, Fue [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Grappe, Hippolyte A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-08-01

    Intermittent sizing is a technique designed to improve the bonding of carbon fiber to a resin when manufacturing composite parts. The purpose of this technique is to improve Sheet Molding Composites (SMC) made of non-continuous carbon fibers while using regular material. At the end of the project, tests showed that improved mechanical properties have been achieved using this technique compared to conventional process. Mechanical properties have been improved by 110% for the peak tensile stress and by 60% for the modulus at the laboratory scale. In this project, Continental Structural Plastics and ORNL have worked to demonstrate the scalability and viability of commercialization of this technique.

  2. Atomistic Model of Fluorescence Intermittency of Colloidal Quantum Dots

    KAUST Repository

    Voznyy, O.

    2014-04-16

    Optoelectronic applications of colloidal quantum dots demand a high emission efficiency, stability in time, and narrow spectral bandwidth. Electronic trap states interfere with the above properties but understanding of their origin remains lacking, inhibiting the development of robust passivation techniques. Here we show that surface vacancies improve the fluorescence yield compared to vacancy-free surfaces, while dynamic vacancy aggregation can temporarily turn fluorescence off. We find that infilling with foreign cations can stabilize the vacancies, inhibiting intermittency and improving quantum yield, providing an explanation of recent experimental observations. © 2014 American Physical Society.

  3. Fractal structures and intermittency in QCD

    International Nuclear Information System (INIS)

    Gustafson, Goesta.

    1990-04-01

    New results are presented for fractal structures and intermittency in QCD parton showers. A geometrical interpretation of the anomalous dimension in QCD is given. It is shown that model predications for factorial moments in the PEP-PETRA energy range are increased. if the properties of directly produced pions are more carefully taken into account

  4. Intermittent demand : Linking forecasting to inventory obsolescence

    NARCIS (Netherlands)

    Teunter, Ruud H.; Syntetos, Aris A.; Babai, M. Zied

    2011-01-01

    The standard method to forecast intermittent demand is that by Croston. This method is available in ERP-type solutions such as SAP and specialised forecasting software packages (e.g. Forecast Pro), and often applied in practice. It uses exponential smoothing to separately update the estimated demand

  5. Acute intermittent porphyria presenting as progressive muscular ...

    African Journals Online (AJOL)

    Acute intermittent porphyria, the most common porphyria affecting the nervous system, typically presents with neurovisceral crises followed by a motor neuropathy. We describe a 23-year-old black South African man presenting with a progressive stuttering, lower motor neuron syndrome developing over months. He had not ...

  6. Cooling tower modification for intermittent operation

    International Nuclear Information System (INIS)

    Midkiff, W.S.

    1975-03-01

    One of the cooling towers at Los Alamos Scientific Laboratory is being operated intermittently. The cooling tower has been modified to restrict air flow and to keep the tower from drying out. The modifications are relatively inexpensive, simple to operate, and have proved effective. (U.S.)

  7. Intermittent preventive treatment of malaria in pregnancy

    DEFF Research Database (Denmark)

    Mbonye, A.K.; Hansen, Kristian Schultz; Bygbjerg, Ib Christian

    2008-01-01

    The main objective of this study was to assess whether traditional birth attendants, drug-shop vendors, community reproductive health workers and adolescent peer mobilisers could administer intermittent preventive treatment (IPTp) with sulfadoxine-pyrimethamine (SP) to pregnant women. The study w...

  8. Management of patients with intermittent claudication

    NARCIS (Netherlands)

    S. Spronk (Sandra)

    2008-01-01

    textabstractIntermittent claudication is the first and mildest manifestation of peripheral arterial disease, caused by the atherosclerotic process of progressive narrowing of one or more of the arteries of the peripheral circulation.1 If the arterial system fails, it results in a progressive oxygen

  9. Intermittent resistive faults in digital cmos circuits

    NARCIS (Netherlands)

    Kerkhoff, Hans G.; Ebrahimi, Hassan

    2015-01-01

    A major threat in extremely dependable high-end process node integrated systems in e.g. Avionics are no failures found (NFF). One category of NFFs is the intermittent resistive fault, often originating from bad (e.g. Via or TSV-based) interconnections. This paper will show the impact of these faults

  10. Intermittent and global transitions in plasma turbulence

    International Nuclear Information System (INIS)

    Vlad, M.; Spineanu, F.; Itoh, K.; Itoh, S.-I.

    2003-07-01

    The dynamics of the transition processes in plasma turbulence described by the nonlinear Langevin equation (1) is studied. We show that intermittent or global transitions between metastable states can appear. The conditions for the generation of these transitions and their statistical characteristics are determined. (author)

  11. A comparative study on low cycle fatigue behaviour of nano and micro Al2O3 reinforced AA2014 particulate hybrid composites

    Directory of Open Access Journals (Sweden)

    R. Senthilkumar

    2015-01-01

    Full Text Available Aluminium based metal matrix composites have drawn more attraction due to their improved properties in structural applications for the past two decades. The fatigue behaviour of composite materials needs to be studied for their structural applications. In this work, powder metallurgy based aluminium (AA2014 alloy reinforced with micro and nano-sized alumina particles were fabricated and consolidated with the hot extrusion process. The evaluation of mechanical properties in the extruded composite was carried out. This composite was subjected to low cycle fatigue test with a constant strain rate. Scanning Electron Microscope (SEM and Transmission Electron Microscope (TEM images were used to evaluate the fatigue behaviour of aluminium-nano composite samples. Enhanced mechanical properties were exhibited by the nano alumina reinforced aluminium composites, when compared to the micron sized alumina reinforced composites. The failure cycle is observed to be higher for the nano alumina reinforced composites when compared with micron sized alumina composites due to a lower order of induced plastic strain.

  12. Intermittency in the particle production and in the nuclear multifragmentation

    International Nuclear Information System (INIS)

    Bozek, P.; Ploszajczak, M.

    1991-01-01

    Intermittency is a manifestation of scale invariance and randomness in physical systems. Intermittency in relativistic heavy-ion collisions and, in particular, the projectile dependence, multiplicity dependence and source-size dependence are discussed in the frame of the model of spatio-temporal intermittency. Moreover, recent theoretical results in intermittency studies of the nuclear multifragmentation are presented. (author) 35 refs., 4 figs., 1 tab

  13. Comparative evaluation of color change between two types of acrylic resin and flexible resin after thermo cycling. An in vitro study.

    Science.gov (United States)

    Hatim, Nadira A; Al-Tahho, Omar Zeno

    2013-09-01

    Evaluation of the effect of different beverages (tea with sugar, coffee with sugar, and Pepsi), and immersion time cycles (2, 4, and 12 weeks) on color change property, and dimensional change of Vertex Dental BV, Netherlands heat cured acrylic resin, recently modified Vertex Dental BV, Netherlands heat cured acrylic resin with additive (20 % banana oil), and Valplast(®) flexible resin (FR) denture base materials by using artificial saliva cycle. The total samples of this study for color, and dimensional changes were 360 samples, divided into three groups according to the type of the material, Vertex Dental BV, Netherlands heat cured acrylic resin, modified heat cured acrylic resin (Vertex with additive 20 % banana oil), and Valplast(®) FR groups, each group contains 120 samples. The thermal cycling used in this study was as follows: The samples were incubated in distilled water at 37 ± 1 °C for 2 days for conditioning. Then, the samples were immersed in beverage solutions for 10 min daily at 50 ± 1 °C temperature for tea, and coffee with sugar, while for Pepsi at 20 ± 1 °C. Then, the samples were immersed in artificial saliva at 37 ± 1 °C for 5 h, and 10 min. This cycle was repeated three times daily, and then the samples were immersed in distilled water at 22 ± 2 °C room temperature for 8 h at night. This cycle was repeated for 2, 4, and 12 weeks. At the end of each time period, the immersed samples were tested to evaluate the color change property. Descriptive statistics, ANOVA, and Duncan's multiple range tests were used to analyze the collected data. The results of this study showed that, in comparison between the materials at different times for colors L*a*b* properties, there were significant differences at P ≤ 0.05 except in color b* at 12 weeks, which showed no significant difference at P > 0.05 between materials. And there was a significant difference in dimensional change at P > 0.05 for different beverages

  14. Intermittent fasting could ameliorate cognitive function against distress by regulation of inflammatory response pathway

    OpenAIRE

    Shojaie, Marjan; Ghanbari, Farzane; Shojaie, Nasrin

    2017-01-01

    Undesirable and desirable effects of stressors on the body are assigned to distress and eustress, respectively. Immune system and brain are the most susceptible parts to stressful conditions, whereas long-lasting alterations in putative immune proteins involved in tension such as corticosterone (CORT), interleukin 6 (IL-6), and tumor necrosis factor-alpha (TNF-α) can impact learning and memory. Intermittent fasting (IF) is a repeated regular cycle of dietary restriction with well-known benefi...

  15. Intermittent Rivers and Biodiversity. Large scale analyses between hydrology and ecology in intermittent rivers

    OpenAIRE

    Blanchard, Q.

    2014-01-01

    Intermittent rivers are characterized by a temporary interruption of their flow which can manifest in a variety of ways, as much on a spatial scale as on a temporal one. This particular aspect of intermittent river hydrology gives rise to unique ecosystems, combining both aquatic and terrestrial habitats. Neglected for a long time by scientists and once considered biologically depauperate and ecologically unimportant, these fragile habitats are nowadays acknowledged for their rendered service...

  16. Uncoupling protein-2 mRNA expression in mice subjected to intermittent hypoxia

    Directory of Open Access Journals (Sweden)

    Luciana Rodrigues Vieira

    2015-04-01

    Full Text Available Objective: To investigate the effect of intermittent hypoxia-a model of obstructive sleep apnea (OSA-on pancreatic expression of uncoupling protein-2 (UCP2, as well as on glycemic and lipid profiles, in C57BL mice. Methods: For 8 h/day over a 35-day period, male C57BL mice were exposed to intermittent hypoxia (hypoxia group or to a sham procedure (normoxia group. The intermittent hypoxia condition involved exposing mice to an atmosphere of 92% N and 8% CO2 for 30 s, progressively reducing the fraction of inspired oxygen to 8 ± 1%, after which they were exposed to room air for 30 s and the cycle was repeated (480 cycles over the 8-h experimental period. Pancreases were dissected to isolate the islets. Real-time PCR was performed with TaqMan assays. Results: Expression of UCP2 mRNA in pancreatic islets was 20% higher in the normoxia group than in the hypoxia group (p = 0.11. Fasting serum insulin was higher in the hypoxia group than in the normoxia group (p = 0.01. The homeostasis model assessment of insulin resistance indicated that, in comparison with the control mice, the mice exposed to intermittent hypoxia showed 15% lower insulin resistance (p = 0.09 and 21% higher pancreatic β-cell function (p = 0.01. Immunohistochemical staining of the islets showed no significant differences between the two groups in terms of the area or intensity of α- and β-cell staining for insulin and glucagon. Conclusions: To our knowledge, this is the first report of the effect of intermittent hypoxia on UCP2 expression. Our findings suggest that UCP2 regulates insulin production in OSA. Further study of the role that UCP2 plays in the glycemic control of OSA patients is warranted.

  17. Intermittency patterns in pp collisions at 360 GeV/c

    International Nuclear Information System (INIS)

    Singh, J.B.; Kohli, J.M.

    1991-01-01

    The intermittency effect has been observed in pp collisions at 360 GeV/c and the strength decreases with the increase in multiplicity. The low multiplicity events in pp data (n ch ≤ 8), anti pp collisions (n ch ≤ 15) at Collider energy and elementary interaction (e + e - , μp) samples have almost the same strength. Most likely, few sources seem to contribute at lower multiplications. The intermittency effect is less in pp data compared to e + e - data, however it is fairly strong as compared to nucleus data. The presently used hadronization models DPM, LUND and FRITIOF do not reproduce the results fully. (orig.)

  18. Cycle training induces muscle hypertrophy and strength gain: strategies and mechanisms.

    Science.gov (United States)

    Ozaki, Hayao; Loenneke, J P; Thiebaud, R S; Abe, T

    2015-03-01

    Cycle training is widely performed as a major part of any exercise program seeking to improve aerobic capacity and cardiovascular health. However, the effect of cycle training on muscle size and strength gain still requires further insight, even though it is known that professional cyclists display larger muscle size compared to controls. Therefore, the purpose of this review is to discuss the effects of cycle training on muscle size and strength of the lower extremity and the possible mechanisms for increasing muscle size with cycle training. It is plausible that cycle training requires a longer period to significantly increase muscle size compared to typical resistance training due to a much slower hypertrophy rate. Cycle training induces muscle hypertrophy similarly between young and older age groups, while strength gain seems to favor older adults, which suggests that the probability for improving in muscle quality appears to be higher in older adults compared to young adults. For young adults, higher-intensity intermittent cycling may be required to achieve strength gains. It also appears that muscle hypertrophy induced by cycle training results from the positive changes in muscle protein net balance.

  19. Male fertility is reduced by chronic intermittent hypoxia mimicking sleep apnea in mice.

    Science.gov (United States)

    Torres, Marta; Laguna-Barraza, Ricardo; Dalmases, Mireia; Calle, Alexandra; Pericuesta, Eva; Montserrat, Josep M; Navajas, Daniel; Gutierrez-Adan, Alfonso; Farré, Ramon

    2014-11-01

    Obstructive sleep apnea (OSA) is characterized by intermittent hypoxia and oxidative stress. However, it is unknown whether intermittent hypoxia mimicking OSA modifies male fertility. We tested the hypothesis that male fertility is reduced by chronic intermittent hypoxia mimicking OSA in a mouse model. Case-control comparison in a murine model. University research laboratory. Eighteen F1 (C57BL/6xCBA) male mice. Mice were subjected to a pattern of periodic hypoxia (20 sec at 5% O2 followed by 40 sec of room air) 6 h/day for 60 days or normoxia. After this period, mice performed a mating trial to determine effective fertility by assessing the number of pregnant females and fetuses. After euthanasia, oxidative stress in testes was assessed by measuring the expression of glutathione peroxidase 1 (Gpx1) and superoxide dismutase-1 (Sod1) by reverse-transcription polymerase chain reaction. Sperm motility was determined by Integrated Semen Analysis System (ISAS). Intermittent hypoxia significantly increased testicular oxidative stress, showing a reduction in the expression of Gpx1 and Sod1 by 38.9% and 34.4%, respectively, as compared with normoxia (P intermittent hypoxia group (P = 0.04). The proportion of pregnant females and number of fetuses per mating was significantly lower in the intermittent hypoxia group (0.33 ± 0.10 and 2.45 ± 0.73, respectively) than in normoxic controls (0.72 ± 0.16 and 5.80 ± 1.24, respectively). These results suggest that the intermittent hypoxia associated with obstructive sleep apnea (OSA) could induce fertility reduction in male patients with this sleep breathing disorder.

  20. Intermittency and Topology of Shock Induced Mixing

    Science.gov (United States)

    Tellez, Jackson; Redondo, Jose M.; Ben Mahjoub, Otman; Malik, Nadeem; Vila, Teresa

    2016-04-01

    are more regular. Mixing in turbulent flows remains less well understood, and in spite research some basic problems are still virtually unexplored. Th e indications suggest that mixing in non-decaying and accelerating turbulent flows are different from those in vortical and steady flows. Fluid element pairs separate, neither linearly nor exponentially but according to a generalized intermittent Richardson's law. Fractal analysis in the laboratory shows that fluid element pairs travel close to each other for a long time until they separate quite suddenly suggest that straining regions around hyperbolic points play an important role in the violent turbulent stirring and in the mechanisms by which turbulence causes fluid element pairs to move apart [6,7]. So the eddies that are most effective in separating fluid elements are those that have a size comparable to the instantaneous separation between the two fluid elements. This is seen in both RT and RM instabilities. For a constant acceleration, the RT instability is found to grow self -similarly according to mixing coefficients which when measured over a comprehensive range of density ratio (Atwood nubers)show that the results are found applicable to supernova exlposions.For an impulsive acceleration (RM), there are two components. The RM impulse from a shock is greatly reduced at high Mach number due to compressive effects in reasonable agreement with linear theory. The ensuing motion is essentially incompressible and described by a power law However, the exponents obtained from the compressible RM experiments are larger than those obtained from incompressible RT experiments. The discrepancy is not well understood but intermittency differences could explain the role of compressibility in fractal media. [1] Linden P.F., Redondo J.M. and Youngs D. (1994) Molecular mixing in Rayleigh-Taylor Instability. Jour. Fluid Mech. 265, 97-124. [2] Redondo, J.M., 1990. The structure of density interfaces. Ph.D. Thesis. DAMTP

  1. Comparative study for axial and radial shuffling scheme effect on the performance of Pb-Bi cooled fast reactors with natural uranium as fuel cycle input

    International Nuclear Information System (INIS)

    Zaki Suud; Indah Rosidah; Maryam Afifah; Ferhat Aziz; Sekimoto, H.

    2013-01-01

    Full text:Comparative study for the Design of Pb-Bi cooled fast reactors with natural uranium as fuel cycle input using special radial shuffling strategy and axial direction modified CANDLE burn-up scheme has been performed. The reactors utilizes UN-PuN as fuel, Eutectic Pb-Bi as coolant, and can be operated without refueling for 10 years in each batch. Reactor design optimization is performed to utilize natural uranium as fuel cycle input. This reactor subdivided into 6-10 regions with equal volume in radial directions. The natural uranium is initially put in region 1, and after one cycle of 10 years of burn-up it is shifted to region 2 and the region 1 is filled by fresh natural uranium fuel. This concept is basically applied to all regions. The calculation has been done by using SRAC-Citation system code and JENDL-3.2 library. The effective multiplication factor change increases monotonously during 10 years reactor operation time. There is significant power distribution change in the central part of the core during the BOC and the EOC in the radial shuffling system. It is larger than that in the case of modified CANDLE case which use axial direction burning region move. The burn-up level of fuel is slowly grows during the first 15 years but then grow faster in the rest of burn-up history. This pattern is a little bit different from the case of modified CANDLE burn-up scheme in Axial direction in which the slow growing burn-up period is relatively longer almost half of the burn-up history. (author)

  2. Knockdown of angiopoietin-like 2 mimics the benefits of intermittent fasting on insulin responsiveness and weight loss.

    Science.gov (United States)

    Martel, Cécile; Pinçon, Anthony; Bélanger, Alexandre Maxime; Luo, Xiaoyan; Gillis, Marc-Antoine; de Montgolfier, Olivia; Thorin-Trescases, Nathalie; Thorin, Éric

    2018-01-01

    Angiopoietin-like 2 (ANGPTL2) is an inflammatory adipokine linking obesity to insulin resistance. Intermittent fasting, on the other hand, is a lifestyle intervention able to prevent obesity and diabetes but difficult to implement and maintain. Our objectives were to characterize a link between ANGPTL2 and intermittent fasting and to investigate whether the knockdown of ANGPTL2 reproduces the benefits of intermittent fasting on weight gain and insulin responsiveness in knockdown and wild-type littermates mice. Intermittent fasting, access to food ad libitum once every other day, was initiated at the age of three months and maintained for four months. Intermittent fasting decreased by 63% (p < 0.05) gene expression of angptl2 in adipose tissue of wild-type mice. As expected, intermittent fasting improved insulin sensitivity (p < 0.05) and limited weight gain (p < 0.05) in wild-type mice. Knockdown mice fed ad libitum, however, were comparable to wild-type mice following the intermittent fasting regimen: insulin sensitivity and weight gain were identical, while intermittent fasting had no additional impact on these parameters in knockdown mice. Energy intake was similar between both wild-type fed intermittent fasting and ANGPTL2 knockdown mice fed ad libitum, suggesting that intermittent fasting and knockdown of ANGPTL2 equally lower feeding efficiency. These results suggest that the reduction of ANGPTL2 could be a useful and promising strategy to prevent obesity and insulin resistance, although further investigation of the mechanisms linking ANGPTL2 and intermittent fasting is warranted. Impact statement Intermittent fasting is an efficient diet pattern to prevent weight gain and improve insulin sensitivity. It is, however, a difficult regimen to follow and compliance is expected to be very low. In this work, we demonstrate that knockdown of ANGPTL2 in mice fed ad libitum mimics the beneficial effects of intermittent fasting on weight gain and insulin

  3. The effects of pentoxifylline on the survival of human glioma cells with continuous and intermittent stereotactic radiosurgery irradiation

    International Nuclear Information System (INIS)

    Eley, Kerry W.; Benedict, Stanley H.; Chung, Theodore D.K.; Kavanagh, Brian D.; Broaddus, William C.; Schmidt-Ullrich, Rupert K.A.; Lin, P.-S.

    2002-01-01

    Purpose: In linac-based stereotactic radiosurgery, treatment is delivered intermittently via multiple individual small radiotherapy arcs. The time lapses between the individual arcs permit greater damage repair and increased tumor cell survival in comparison with continuous irradiation. Because pentoxifylline (PTX) has been reported to prevent radiation-induced cell cycle arrest at the G2/M checkpoint, where damage repair is critically linked to cell survival, we hypothesized that PTX would exert a favorable radiosensitization effect by reducing the recovery observed during intermittent stereotactic radiosurgery. Methods and Materials: The human glioma cell line T98G was used to study the effects of continuous vs. intermittent irradiation with or without PTX. Cell cycle patterns were studied using flow cytometry. Clonogenic assays of single cells and spheroid outgrowth assays provided a quantitative measure of PTX-mediated radiosensitization. The PTX effect upon cells in low oxygen conditions was also studied in vitro after enzymatic oxygen scavenging. Results: Flow Cytometry: T98G cells exposed to both continuous and intermittent irradiation exhibit similar arrest at the G2/M checkpoint. The addition of 2 mM PTX significantly reduced the radiation-induced G2/M block in both irradiation schemes. Clonogenic Assays: The same PTX concentration applied before a continuous dose of 12 Gy, two intermittent doses of 6 Gy, or three intermittent doses of 4 Gy, all given within a 1-h interval, consistently caused radiosensitization. The drug enhancement ratios for PTX were 1.5, 2.7, and 6.0 for the continuous and two different intermittent dose schedules, respectively. Adding PTX after irradiation yielded lower enhancement ratios than pre-irradiation application. A similar pattern was observed after total doses of 4, 6, 9, or 12 Gy, as well. In low oxygen conditions, PTX was seen to have the same effects as in normoxic conditions. Spheroid Outgrowth Assays: The in vitro PTX

  4. Cell-cycle and suppressor proteins expression in uterine cervix in HIV/HPV co-infection: comparative study by tissue micro-array (TMA)

    International Nuclear Information System (INIS)

    Nicol, Alcina F; Pirmez, Claude; Pires, Andréa Rodrigues Cordovil; Souza, Simone R de; Nuovo, Gerard J; Grinsztejn, Beatriz; Tristão, Aparecida; Russomano, Fabio B; Velasque, Luciane; Silva, José R Lapa e

    2008-01-01

    The oncoproteins of human papillomavirus (HPVs) directly effect cell-cycle control. We hypothesize that regulatory and cell cycle protein expression might be additionally modified in the cervix of HIV/HPV co-infected women. We analyzed the expression of Rb, p27, VEGF and Elf-1 transcriptor factor by immunohistochemistry in 163 paraffin-embeded cervical samples using Tissue Micro-Array (TMA) and correlated this to HIV-1 and HPV infection. HIV/HPV co-infection was associated with a significant increase in expression (p < 0.001) of VEGF and p27 in both low and high grade CIN when compared to the cervices of women infected by HPV alone. Decreased Rb expression was evident with increased CIN grade in the cervices of women infected with HPV alone (p = 0.003 average of cells/mm 2 in CIN I: 17.9, CIN II/III: 4.8, and tumor 3.9). Rb expression increased 3-fold for both low and high grade CIN with HPV/HIV-1 co-infection compared to HPV infection alone but did not reach statistical significance. There was a significant increase in Elf-1 expression in HPV+/HIV- women with CIN II/III and tumor (average of cells/mm 2 in CIN I: 63.8; CIN II/III: 115.7 and tumor: 112.0, p = 0.005), in comparison to controls. Co-infection of HPV and HIV leads to significant increase in the VEGF and p27 expression when compared to HPV+/HIV-negative infection that could facilitate viral persistence and invasive tumor development

  5. Cell-cycle and suppressor proteins expression in uterine cervix in HIV/HPV co-infection: comparative study by tissue micro-array (TMA).

    Science.gov (United States)

    Nicol, Alcina F; Pires, Andréa Rodrigues Cordovil; de Souza, Simone R; Nuovo, Gerard J; Grinsztejn, Beatriz; Tristão, Aparecida; Russomano, Fabio B; Velasque, Luciane; Lapa e Silva, José R; Pirmez, Claude

    2008-10-07

    The oncoproteins of human papillomavirus (HPVs) directly effect cell-cycle control. We hypothesize that regulatory and cell cycle protein expression might be additionally modified in the cervix of HIV/HPV co-infected women. We analyzed the expression of Rb, p27, VEGF and Elf-1 transcriptor factor by immunohistochemistry in 163 paraffin-embeded cervical samples using Tissue Micro-Array (TMA) and correlated this to HIV-1 and HPV infection. HIV/HPV co-infection was associated with a significant increase in expression (p < 0.001) of VEGF and p27 in both low and high grade CIN when compared to the cervices of women infected by HPV alone. Decreased Rb expression was evident with increased CIN grade in the cervices of women infected with HPV alone (p = 0.003 average of cells/mm2 in CIN I: 17.9, CIN II/III: 4.8, and tumor 3.9). Rb expression increased 3-fold for both low and high grade CIN with HPV/HIV-1 co-infection compared to HPV infection alone but did not reach statistical significance. There was a significant increase in Elf-1 expression in HPV+/HIV- women with CIN II/III and tumor (average of cells/mm2 in CIN I: 63.8; CIN II/III: 115.7 and tumor: 112.0, p = 0.005), in comparison to controls. Co-infection of HPV and HIV leads to significant increase in the VEGF and p27 expression when compared to HPV+/HIV-negative infection that could facilitate viral persistence and invasive tumor development.

  6. The effect of intermittent fasting on blood pressure variability in patients with newly diagnosed hypertension or prehypertension.

    Science.gov (United States)

    Erdem, Yunus; Özkan, Gülsüm; Ulusoy, Şükrü; Arıcı, Mustafa; Derici, Ülver; Şengül, Şule; Sindel, Şükrü; Ertürk, Şehsuvar

    2018-01-01

    Intermittent fasting is a phenomenon which can be observed in most humans. The effect of intermittent fasting on blood pressure variability (BPV) has not previously been investigated. The purpose of this study was to assess the effect of fasting on blood pressure (BP) (with office, home, central, and ambulatory blood pressure monitoring [ABPM]) and on BPV. Sixty individuals were included in the study. Office, home, ABPM, and central BP measurements were performed before and during intermittent fasting. Standard deviation and coefficient variation were used for office and home BPV measurement, while the smoothness index was used to calculate ABPM variability. Patients' BP and BPV values before and during intermittent fasting were then compared. Intermittent fasting resulted in a significant decrease in office BP values and ABPM measurements but caused no significant change in home and central BP measurements. Twenty-four hour urinary sodium excretion decreased. Smoothness values obtained from ABPM measurements were low; in other words, BPV was greater. BPV was higher in patients who woke up to eat before sunrise, but BPV was low in patients with high body mass index. Intermittent fasting produced a significant decrease in BP values in terms of office and ABPM measurements in this study but caused no significant change in central BP and home measurements. We also identified an increase in BPV during intermittent fasting, particularly in patients who rose before sunrise. Copyright © 2017 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.

  7. Environmental analysis of plastic production processes: comparing petroleum-based polypropylene and polyethylene with biologically-based poly-beta-hydroxybutyric acid using life cycle analysis.

    Science.gov (United States)

    Harding, K G; Dennis, J S; von Blottnitz, H; Harrison, S T L

    2007-05-31

    Polymers based on olefins have wide commercial applicability. However, they are made from non-renewable resources and are characterised by difficulty in disposal where recycle and re-use is not feasible. Poly-beta-hydroxybutyric acid (PHB) provides one example of a polymer made from renewable resources. Before motivating its widespread use, the advantages of a renewable polymer must be weighed against the environmental aspects of its production. Previous studies relating the environmental impacts of petroleum-based and bio-plastics have centred on the impact categories of global warming and fossil fuel depletion. Cradle-to-grave studies report equivalent or reduced global warming impacts, in comparison to equivalent polyolefin processes. This stems from a perceived CO(2) neutral status of the renewable resource. Indeed, no previous work has reported the results of a life cycle assessment (LCA) giving the environmental impacts in all major categories. This study investigates a cradle-to-gate LCA of PHB production taking into account net CO(2) generation and all major impact categories. It compares the findings with similar studies of polypropylene (PP) and polyethylene (PE). It is found that, in all of the life cycle categories, PHB is superior to PP. Energy requirements are slightly lower than previously observed and significantly lower than those for polyolefin production. PE impacts are lower than PHB values in acidification and eutrophication.

  8. Intermittent pneumatic leg compressions acutely upregulate VEGF and MCP-1 expression in skeletal muscle.

    Science.gov (United States)

    Roseguini, Bruno T; Mehmet Soylu, S; Whyte, Jeffrey J; Yang, H T; Newcomer, Sean; Laughlin, M Harold

    2010-06-01

    Application of intermittent pneumatic compressions (IPC) is an extensively used therapeutic strategy in vascular medicine, but the mechanisms by which this method works are unclear. We tested the hypothesis that acute application (150 min) of cyclic leg compressions in a rat model signals upregulation of angiogenic factors in skeletal muscle. To explore the impact of different pressures and frequency of compressions, we divided rats into four groups as follows: 120 mmHg (2 s inflation/2 s deflation), 200 mmHg (2 s/2 s), 120 mmHg (4 s/16 s), and control (no intervention). Blood flow and leg oxygenation (study 1) and the mRNA expression of angiogenic mediators in the rat tibialis anterior muscle (study 2) were assessed after a single session of IPC. In all three groups exposed to the intervention, a modest hyperemia (approximately 37% above baseline) between compressions and a slight, nonsignificant increase in leg oxygen consumption (approximately 30%) were observed during IPC. Compared with values in the control group, vascular endothelial growth factor (VEGF) and monocyte chemotactic protein-1 (MCP-1) mRNA increased significantly (P < 0.05) only in rats exposed to the higher frequency of compressions (2 s on/2 s off). Endothelial nitric oxide synthase, matrix metalloproteinase-2, and hypoxia-inducible factor-1alpha mRNA did not change significantly following the intervention. These findings show that IPC application augments the mRNA content of key angiogenic factors in skeletal muscle. Importantly, the magnitude of changes in mRNA expression appeared to be modulated by the frequency of compressions such that a higher frequency (15 cycles/min) evoked more robust changes in VEGF and MCP-1 compared with a lower frequency (3 cycles/min).

  9. A randomized assessor-blind trial comparing highly purified hMG and recombinant FSH in a GnRH antagonist cycle with compulsory single-blastocyst transfer

    DEFF Research Database (Denmark)

    Devroey, Paul; Pellicer, Antonio; Nyboe Andersen, Anders

    2012-01-01

    MG versus 27% with rFSH for the per-protocol (PP) population and 29% versus 27% for the intention-to-treat (ITT) population. Noninferiority of hphMG compared to rFSH was established. Considering frozen cycles initiated within 1 year, the cumulative live birth rate for a single stimulation cycle was 40...... blastocyst replacement in natural cycles initiated within 1 year of each patient's start of treatment. MAIN OUTCOME MEASURE(S): Ongoing pregnancy (primary end point) and live birth rates, as well as pharmacodynamic parameters. RESULT(S): The ongoing pregnancy rate after a fresh cycle was 30% with hph...

  10. Intermittent Nitrate Use and Risk of Hip Fracture

    Science.gov (United States)

    Misra, Devyani; Peloquin, Christine; Kiel, Douglas P.; Neogi, Tuhina; Lu, Na; Zhang, Yuqing

    2016-01-01

    Purpose Nitrates, commonly used anti-anginal medications, also have beneficial effect on bone remodeling and bone density, particularly with intermittent use. However, their effect on fracture risk is not clear. We examined the relation of short-acting nitrate use (proxy for intermittent use) to the risk of hip fracture in a large cohort of older adults with ischemic heart disease. Materials and Methods Participants ≥ 60 years old with ischemic heart disease and without history of hip fracture from The Health Improvement Network (THIN), an electronic medical records database in the UK, were included. The association of incident (new) use of short-acting nitrate formulations (nitroglycerin sublingual/spray/ointment or ISDN injection/sprays) with incident (new-onset) hip fracture risk was examined by plotting Kaplan-Maier curves and calculating Hazard ratios (HR) using Cox proportional hazards regression models. Competing risk by death was analyzed in separate analyses. Results Among 14, 451 pairs of matched nitrate users and non-users (mean age 72±7.6, 41% women for each cohort), 573 fractures occurred during follow up (257 nitrate users; 316 non-users). Hip fracture risk was 33% lower among short-acting nitrate users compared with non-users (HR=0.67, 95% CI 0.53–0.85, p=0.0008). Competing risk analysis by death did not change effect estimates. Conclusion In this large population-based cohort of older adults with ischemic heart disease, we found significant reduction in hip fracture risk with use of short-acting nitrates (intermittent use). Future studies are warranted given the potential for nitrates to be potent, inexpensive and readily available anti-osteoporotic agents. PMID:27720852

  11. Intermittency in MHD turbulence and coronal nanoflares modelling

    Directory of Open Access Journals (Sweden)

    P. Veltri

    2005-01-01

    Full Text Available High resolution numerical simulations, solar wind data analysis, and measurements at the edges of laboratory plasma devices have allowed for a huge progress in our understanding of MHD turbulence. The high resolution of solar wind measurements has allowed to characterize the intermittency observed at small scales. We are now able to set up a consistent and convincing view of the main properties of MHD turbulence, which in turn constitutes an extremely efficient tool in understanding the behaviour of turbulent plasmas, like those in solar corona, where in situ observations are not available. Using this knowledge a model to describe injection, due to foot-point motions, storage and dissipation of MHD turbulence in coronal loops, is built where we assume strong longitudinal magnetic field, low beta and high aspect ratio, which allows us to use the set of reduced MHD equations (RMHD. The model is based on a shell technique in the wave vector space orthogonal to the strong magnetic field, while the dependence on the longitudinal coordinate is preserved. Numerical simulations show that injected energy is efficiently stored in the loop where a significant level of magnetic and velocity fluctuations is obtained. Nonlinear interactions give rise to an energy cascade towards smaller scales where energy is dissipated in an intermittent fashion. Due to the strong longitudinal magnetic field, dissipative structures propagate along the loop, with the typical speed of the Alfvén waves. The statistical analysis on the intermittent dissipative events compares well with all observed properties of nanoflare emission statistics. Moreover the recent observations of non thermal velocity measurements during flare occurrence are well described by the numerical results of the simulation model. All these results naturally emerge from the model dynamical evolution without any need of an ad-hoc hypothesis.

  12. Intermittent Hypoxia Enhances Functional Connectivity of Midcervical Spinal Interneurons

    Science.gov (United States)

    Streeter, Kristi A.; Sunshine, Michael D.; Patel, Shreya; Gonzalez-Rothi, Elisa J.; Reier, Paul J.

    2017-01-01

    Brief, intermittent oxygen reductions [acute intermittent hypoxia (AIH)] evokes spinal plasticity. Models of AIH-induced neuroplasticity have focused on motoneurons; however, most midcervical interneurons (C-INs) also respond to hypoxia. We hypothesized that AIH would alter the functional connectivity between C-INs and induce persistent changes in discharge. Bilateral phrenic nerve activity was recorded in anesthetized and ventilated adult male rats and a multielectrode array was used to record C4/5 spinal discharge before [baseline (BL)], during, and 15 min after three 5 min hypoxic episodes (11% O2, H1–H3). Most C-INs (94%) responded to hypoxia by either increasing or decreasing firing rate. Functional connectivity was examined by cross-correlating C-IN discharge. Correlograms with a peak or trough were taken as evidence for excitatory or inhibitory connectivity between C-IN pairs. A subset of C-IN pairs had increased excitatory cross-correlations during hypoxic episodes (34%) compared with BL (19%; p phrenic motoneurons and excitatory inputs to these “pre-phrenic” cells increased during AIH. We conclude that AIH alters connectivity of the midcervical spinal network. To our knowledge, this is the first demonstration that AIH induces plasticity within the propriospinal network. SIGNIFICANCE STATEMENT Acute intermittent hypoxia (AIH) can trigger spinal plasticity associated with sustained increases in respiratory, somatic, and/or autonomic motor output. The impact of AIH on cervical spinal interneuron (C-IN) discharge and connectivity is unknown. Our results demonstrate that AIH recruits excitatory C-INs into the spinal respiratory (phrenic) network. AIH also enhances excitatory and reduces inhibitory connections among the C-IN network. We conclude that C-INs are part of the respiratory, somatic, and/or autonomic response to AIH, and that propriospinal plasticity may contribute to sustained increases in motor output after AIH. PMID:28751456

  13. Intermittency analysis of correlated data

    International Nuclear Information System (INIS)

    Wosiek, B.

    1992-01-01

    We describe the method of the analysis of the dependence of the factorial moments on the bin size in which the correlations between the moments computed for different bin sizes are taken into account. For large multiplicity nucleus-nucleus data inclusion of the correlations does not change the values of the slope parameter, but gives errors significantly reduced as compared to the case of fits with no correlations. (author)

  14. Intermittent control: a computational theory of human control.

    Science.gov (United States)

    Gawthrop, Peter; Loram, Ian; Lakie, Martin; Gollee, Henrik

    2011-02-01

    The paradigm of continuous control using internal models has advanced understanding of human motor control. However, this paradigm ignores some aspects of human control, including intermittent feedback, serial ballistic control, triggered responses and refractory periods. It is shown that event-driven intermittent control provides a framework to explain the behaviour of the human operator under a wider range of conditions than continuous control. Continuous control is included as a special case, but sampling, system matched hold, an intermittent predictor and an event trigger allow serial open-loop trajectories using intermittent feedback. The implementation here may be described as "continuous observation, intermittent action". Beyond explaining unimodal regulation distributions in common with continuous control, these features naturally explain refractoriness and bimodal stabilisation distributions observed in double stimulus tracking experiments and quiet standing, respectively. Moreover, given that human control systems contain significant time delays, a biological-cybernetic rationale favours intermittent over continuous control: intermittent predictive control is computationally less demanding than continuous predictive control. A standard continuous-time predictive control model of the human operator is used as the underlying design method for an event-driven intermittent controller. It is shown that when event thresholds are small and sampling is regular, the intermittent controller can masquerade as the underlying continuous-time controller and thus, under these conditions, the continuous-time and intermittent controller cannot be distinguished. This explains why the intermittent control hypothesis is consistent with the continuous control hypothesis for certain experimental conditions.

  15. CONDITIONED ANALYSIS OF HIGH-LATITUDE SOLAR WIND INTERMITTENCY

    International Nuclear Information System (INIS)

    D'Amicis, R.; Consolini, G.; Bavassano, B.; Bruno, R.

    2012-01-01

    The solar wind is a turbulent medium displaying intermittency. Its intermittent features have been widely documented and studied, showing how the intermittent character is different in fast and slow wind. In this paper, a statistical conditioned analysis of the solar wind intermittency for a period of high-latitude fast solar wind is presented. In particular, the intermittent features are investigated as a function of the Alfvénic degree of fluctuations at a given scale. The results show that the main contribution to solar wind intermittency is due to non-Alfvénic structures, while Alfvénic increments are found to be characterized by a smaller level of intermittency than the previous ones. Furthermore, the lifetime statistics of Alfvénic periods are discussed in terms of a multiscale texture of randomly oriented flux tubes.

  16. Chronic intermittent fasting improves cognitive functions and brain structures in mice.

    Directory of Open Access Journals (Sweden)

    Liaoliao Li

    Full Text Available Obesity is a major health issue. Obesity started from teenagers has become a major health concern in recent years. Intermittent fasting increases the life span. However, it is not known whether obesity and intermittent fasting affect brain functions and structures before brain aging. Here, we subjected 7-week old CD-1 wild type male mice to intermittent (alternate-day fasting or high fat diet (45% caloric supplied by fat for 11 months. Mice on intermittent fasting had better learning and memory assessed by the Barnes maze and fear conditioning, thicker CA1 pyramidal cell layer, higher expression of drebrin, a dendritic protein, and lower oxidative stress than mice that had free access to regular diet (control mice. Mice fed with high fat diet was obese and with hyperlipidemia. They also had poorer exercise tolerance. However, these obese mice did not present significant learning and memory impairment or changes in brain structures or oxidative stress compared with control mice. These results suggest that intermittent fasting improves brain functions and structures and that high fat diet feeding started early in life does not cause significant changes in brain functions and structures in obese middle-aged animals.

  17. Increasing walking in patients with intermittent claudication: Protocol for a randomised controlled trial

    Directory of Open Access Journals (Sweden)

    O'Carroll Ronan E

    2010-10-01

    Full Text Available Abstract Background People with intermittent claudication are at increased risk of death from heart attack and stroke compared to matched controls. Surgery for intermittent claudication is for symptom management and does not reduce the risk of cardiovascular morbidity and mortality. Increasing physical activity can reduce claudication symptoms and may improve cardiovascular health. This paper presents the pilot study protocol for a randomised controlled trial to test whether a brief psychological intervention leads to increased physical activity, improvement in quality of life, and a reduction in the demand for surgery, for patients with intermittent claudication. Methods/Design We aim to recruit 60 patients newly diagnosed with intermittent claudication, who will be randomised into two groups. The control group will receive usual care, and the treatment group will receive usual care and a brief 2-session psychological intervention to modify illness and walking beliefs and develop a walking action plan. The primary outcome will be walking, measured by pedometer. Secondary outcomes will include quality of life and uptake of surgery for symptom management. Participants will be followed up after (a 4 months, (b 1 year and (c 2 years. Discussion This study will assess the acceptability and efficacy of a brief psychological intervention to increase walking in patients with intermittent claudication, both in terms of the initiation, and maintenance of behaviour change. This is a pilot study, and the results will inform the design of a larger multi-centre trial. Trial Registration Current Controlled Trials ISRCTN28051878

  18. External intermittency prediction using AMR solutions of RANS turbulence and transported PDF models

    Science.gov (United States)

    Olivieri, D. A.; Fairweather, M.; Falle, S. A. E. G.

    2011-12-01

    External intermittency in turbulent round jets is predicted using a Reynolds-averaged Navier-Stokes modelling approach coupled to solutions of the transported probability density function (pdf) equation for scalar variables. Solutions to the descriptive equations are obtained using a finite-volume method, combined with an adaptive mesh refinement algorithm, applied in both physical and compositional space. This method contrasts with conventional approaches to solving the transported pdf equation which generally employ Monte Carlo techniques. Intermittency-modified eddy viscosity and second-moment turbulence closures are used to accommodate the effects of intermittency on the flow field, with the influence of intermittency also included, through modifications to the mixing model, in the transported pdf equation. Predictions of the overall model are compared with experimental data on the velocity and scalar fields in a round jet, as well as against measurements of intermittency profiles and scalar pdfs in a number of flows, with good agreement obtained. For the cases considered, predictions based on the second-moment turbulence closure are clearly superior, although both turbulence models give realistic predictions of the bimodal scalar pdfs observed experimentally.

  19. Chronic intermittent fasting improves cognitive functions and brain structures in mice.

    Science.gov (United States)

    Li, Liaoliao; Wang, Zhi; Zuo, Zhiyi

    2013-01-01

    Obesity is a major health issue. Obesity started from teenagers has become a major health concern in recent years. Intermittent fasting increases the life span. However, it is not known whether obesity and intermittent fasting affect brain functions and structures before brain aging. Here, we subjected 7-week old CD-1 wild type male mice to intermittent (alternate-day) fasting or high fat diet (45% caloric supplied by fat) for 11 months. Mice on intermittent fasting had better learning and memory assessed by the Barnes maze and fear conditioning, thicker CA1 pyramidal cell layer, higher expression of drebrin, a dendritic protein, and lower oxidative stress than mice that had free access to regular diet (control mice). Mice fed with high fat diet was obese and with hyperlipidemia. They also had poorer exercise tolerance. However, these obese mice did not present significant learning and memory impairment or changes in brain structures or oxidative stress compared with control mice. These results suggest that intermittent fasting improves brain functions and structures and that high fat diet feeding started early in life does not cause significant changes in brain functions and structures in obese middle-aged animals.

  20. Anaerobic co-digestion of municipal food waste and sewage sludge: A comparative life cycle assessment in the context of a waste service provision.

    Science.gov (United States)

    Edwards, Joel; Othman, Maazuza; Crossin, Enda; Burn, Stewart

    2017-01-01

    This study used life cycle assessment to evaluate the environmental impact of anaerobic co-digestion (AcoD) and compared it against the current waste management system in two case study areas. Results indicated AcoD to have less environmental impact for all categories modelled excluding human toxicity, despite the need to collect and pre-treat food waste separately. Uncertainty modelling confirmed that AcoD has a 100% likelihood of a smaller global warming potential, and for acidification, eutrophication and fossil fuel depletion AcoD carried a greater than 85% confidence of inducing a lesser impact than the current waste service. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  1. A Comparative of Life Cycle Assessment of a Conventional Van and a Battery Electric Van for an Online Shopping System in Thailand

    Science.gov (United States)

    Koiwanit, J.; Hamontree, C.

    2018-05-01

    The transportation sector is responsible for one of the main emitters of large quantities of pollutions to the atmosphere, which impacts local, regional or global environment receptors. In Thailand, many retail chains have been trying to launch many campaigns and projects to reduce GHG emissions together with offering the best convenience services to serve customers’ needs. By promoting an online shopping system for the workplace, this will mitigate even more of the air pollutants than the conventional online shopping system, where the products are delivered to customer’s doorsteps. This study aims to investigate and compare the impact of different vehicle technologies for an online shopping using Life Cycle Assessment (LCA) methodology especially in the vehicle use phase. The observed results showed that the electric van has the potential of reducing emissions and consequently showed lower impacts in most impact categories.

  2. Removal of pharmaceuticals in conventionally treated wastewater by a polishing Moving Bed Biofilm Reactor (MBBR) with intermittent feeding

    DEFF Research Database (Denmark)

    Tang, Kai; Ooi, Gordon Tze Hoong; Litty, Klaus

    2017-01-01

    of pharmaceuticals was enhanced through the intermittent feeding of the MBBR. First-order rate constants for pharmaceutical removal, normalised to biomass, were significantly higher compared to other studies on activated sludge and suspended biofilms, especially for diclofenac, metoprolol and atenolol. Due...... to the intermittently feeding, degradation of diclofenac occurred with a half-life of only 2.1 hours and was thus much faster than any hitherto described wastewater bioreactor treatment....

  3. Comparison Between 30-15 Intermittent Fitness Test and Multistage Field Test on Physiological Responses in Wheelchair Basketball Players

    OpenAIRE

    Weissland, Thierry; Faupin, Arnaud; Borel, Benoit; Leprêtre, Pierre-Marie

    2015-01-01

    The intermittent nature of wheelchair court sports suggests using a similar protocol to assess repeated shuttles and recovery abilities. This study aimed to compare performances, physiological responses and perceived rating exertion obtained from the continuous multistage field test (MFT) and the 30-15 intermittent field test (30-15IFT). Eighteen trained wheelchair basketball players (WBP) (WBP: 32.0 ? 5.7 y, IWBF classification: 2.9 ? 1.1 points) performed both incremental field tests in ran...

  4. Intermittency exponent of the turbulent energy cascade

    International Nuclear Information System (INIS)

    Cleve, J.; Greiner, M.; Pearson, B.R.; Sreenivasan, K.R.

    2006-12-01

    We consider the turbulent energy dissipation from one-dimensional records in experiments using air and gaseous helium at cryogenic temperatures, and obtain the intermittency exponent via the two-point correlation function of the energy dissipation. The air data are obtained in a number of flows in a wind tunnel and the atmospheric boundary layer at a height of about 35 m above the ground. The helium data correspond to the centerline of a jet exhausting into a container. The air data on the intermittency exponent are consistent with each other and with a trend that increases with the Taylor microscale Reynolds number, R λ , of up to about 1000 and saturates thereafter. On the other hand, the helium data cluster around a constant value at nearly all R λ , this being about half of the asymptotic value for the air data. Some possible explanation is offered for this anomaly. (author)

  5. Effects of intermittent hypoxia on running economy.

    Science.gov (United States)

    Burtscher, M; Gatterer, H; Faulhaber, M; Gerstgrasser, W; Schenk, K

    2010-09-01

    We investigated the effects of two 5-wk periods of intermittent hypoxia on running economy (RE). 11 male and female middle-distance runners were randomly assigned to the intermittent hypoxia group (IHG) or to the control group (CG). All athletes trained for a 13-wk period starting at pre-season until the competition season. The IHG spent additionally 2 h at rest on 3 days/wk for the first and the last 5 weeks in normobaric hypoxia (15-11% FiO2). RE, haematological parameters and body composition were determined at low altitude (600 m) at baseline, after the 5 (th), the 8 (th) and the 13 (th) week of training. RE, determined by the relative oxygen consumption during submaximal running, (-2.3+/-1.2 vs. -0.3+/-0.7 ml/min/kg, Ptraining phase. Georg Thieme Verlag KG Stuttgart . New York.

  6. Optimal intermittent search strategies: smelling the prey

    International Nuclear Information System (INIS)

    Revelli, J A; Wio, H S; Rojo, F; Budde, C E

    2010-01-01

    We study the kinetics of the search of a single fixed target by a searcher/walker that performs an intermittent random walk, characterized by different states of motion. In addition, we assume that the walker has the ability to detect the scent left by the prey/target in its surroundings. Our results, in agreement with intuition, indicate that the prey's survival probability could be strongly reduced (increased) if the predator is attracted (or repelled) by the trace left by the prey. We have also found that, for a positive trace (the predator is guided towards the prey), increasing the inhomogeneity's size reduces the prey's survival probability, while the optimal value of α (the parameter that regulates intermittency) ceases to exist. The agreement between theory and numerical simulations is excellent.

  7. Optimal intermittent search strategies: smelling the prey

    Energy Technology Data Exchange (ETDEWEB)

    Revelli, J A; Wio, H S [Instituto de Fisica de Cantabria, Universidad de Cantabria and CSIC, E-39005 Santander (Spain); Rojo, F; Budde, C E [Fa.M.A.F., Universidad Nacional de Cordoba, Ciudad Universitaria, X5000HUA Cordoba (Argentina)

    2010-05-14

    We study the kinetics of the search of a single fixed target by a searcher/walker that performs an intermittent random walk, characterized by different states of motion. In addition, we assume that the walker has the ability to detect the scent left by the prey/target in its surroundings. Our results, in agreement with intuition, indicate that the prey's survival probability could be strongly reduced (increased) if the predator is attracted (or repelled) by the trace left by the prey. We have also found that, for a positive trace (the predator is guided towards the prey), increasing the inhomogeneity's size reduces the prey's survival probability, while the optimal value of {alpha} (the parameter that regulates intermittency) ceases to exist. The agreement between theory and numerical simulations is excellent.

  8. Optimal Dynamics of Intermittent Water Supply

    Science.gov (United States)

    Lieb, Anna; Wilkening, Jon; Rycroft, Chris

    2014-11-01

    In many urban areas of the developing world, piped water is supplied only intermittently, as valves direct water to different parts of the water distribution system at different times. The flow is transient, and may transition between free-surface and pressurized, resulting in complex dynamical features with important consequences for water suppliers and users. These consequences include degradation of distribution system components, compromised water quality, and inequitable water availability. The goal of this work is to model the important dynamics and identify operating conditions that mitigate certain negative effects of intermittent water supply. Specifically, we will look at valve parameters occurring as boundary conditions in a network model of transient, transition flow through closed pipes. Optimization will be used to find boundary values to minimize pressure gradients and ensure equitable water availability.

  9. Estudo comparativo entre a pressão positiva intermitente (Reanimador de Müller e contínua no pós-operatório de cirurgia de revascularização do miocárdio Comparative study between intermittent (Müller Reanimator and continuous positive airway pressure in the postoperative period of coronary artery bypass grafting

    Directory of Open Access Journals (Sweden)

    Andréa Pires Müller

    2006-03-01

    Full Text Available OBJETIVO: Comparar o efeito da aplicação da pressão positiva intermitente e contínua em pacientes no pós-operatório de cirurgia de revascularização do miocárdio. MÉTODOS: Neste estudo foram considerados quarenta pacientes, divididos em dois grupos: um submetido a pressão positiva contínua (Grupo CPAP, e outro submetido a pressão intermitente (Grupo Reanimador de Müller. Os pacientes foram avaliados nos momentos: pré-operatório, 3ª, 24ª e 48ª horas, em relação às diversas variáveis do estudo. RESULTADOS: Os grupos de pacientes eram homogêneos em relação a diversas variáveis demográficas e clínicas. Os valores gasométricos de PO2, PCO2 e SO2 estiveram dentro dos parâmetros de normalidade e não foram encontradas diferenças significantes entre os grupos. Na ventilometria os grupos apresentaram diferenças significativas no volume corrente e freqüência respiratória no pós-operatório de 48 horas. A dispnéia e a participação da musculatura acessória, nas avaliações do pós-operatório, foram encontradas com freqüência significativamente maior nos pacientes submetidos ao CPAP. Pacientes submetidos ao Reanimador de Müller apresentaram radiografia de tórax normal com maior freqüência do que pacientes submetidos ao CPAP. CONCLUSÃO: Observou-se que ambos os recursos foram capazes de manter valores de PO2, PCO2 e SO2 dentro da normalidade. Porém, quando se busca a reexpansão pulmonar, com menor carga de trabalho imposta, o Reanimador de Müller foi mais efetivo pela forma mais rápida de ação e, conseqüentemente, apresentou menores índices de dispnéia, freqüência respiratória (FR e atividade de musculatura acessória.OBJECTIVE: To compare the effect of the use of intermittent and continuous positive airway pressure in postoperative patients undergoing coronary artery bypass grafting. METHODS: This study included forty patients divided into two groups: one undergoing continuous positive airway

  10. AN ELDERLY WOMAN WITH INTERMITTENT CLAUDICATION

    Directory of Open Access Journals (Sweden)

    Nayyer Naveed Wazir

    2006-01-01

    Full Text Available This case report illustrates the misdiagnosis of intermittent claudication in an elderly with multiple cardiac risk factors. Careful clinical evaluation and imaging shifts the diagnosis from peripheral vascular disease to spinal stenosis. The decision whether to offer conservative therapy or proceed to spinal surgery requires an accurate assessment of the severity of the symptoms without ignoring the important role of patient preferences.

  11. Long-range forecasting of intermittent streamflow

    OpenAIRE

    F. F. van Ogtrop; R. W. Vervoort; G. Z. Heller; D. M. Stasinopoulos; R. A. Rigby

    2011-01-01

    Long-range forecasting of intermittent streamflow in semi-arid Australia poses a number of major challenges. One of the challenges relates to modelling zero, skewed, non-stationary, and non-linear data. To address this, a statistical model to forecast streamflow up to 12 months ahead is applied to five semi-arid catchments in South Western Queensland. The model uses logistic regression through Generalised Additive Models for Location, Scale and Shape (GAMLSS) to determine th...

  12. Long-range forecasting of intermittent streamflow

    OpenAIRE

    F. F. van Ogtrop; R. W. Vervoort; G. Z. Heller; D. M. Stasinopoulos; R. A. Rigby

    2011-01-01

    Long-range forecasting of intermittent streamflow in semi-arid Australia poses a number of major challenges. One of the challenges relates to modelling zero, skewed, non-stationary, and non-linear data. To address this, a probabilistic statistical model to forecast streamflow 12 months ahead is applied to five semi-arid catchments in South Western Queensland. The model uses logistic regression through Generalised Additive Models for Location, Scale and Shape (GAMLSS) to determine the probabil...

  13. Assessing market uncertainty by means of a time-varying intermittency parameter for asset price fluctuations

    Science.gov (United States)

    Rypdal, Martin; Sirnes, Espen; Løvsletten, Ola; Rypdal, Kristoffer

    2013-08-01

    Maximum likelihood estimation techniques for multifractal processes are applied to high-frequency data in order to quantify intermittency in the fluctuations of asset prices. From time records as short as one month these methods permit extraction of a meaningful intermittency parameter λ characterising the degree of volatility clustering. We can therefore study the time evolution of volatility clustering and test the statistical significance of this variability. By analysing data from the Oslo Stock Exchange, and comparing the results with the investment grade spread, we find that the estimates of λ are lower at times of high market uncertainty.

  14. Efficient search by optimized intermittent random walks

    International Nuclear Information System (INIS)

    Oshanin, Gleb; Lindenberg, Katja; Wio, Horacio S; Burlatsky, Sergei

    2009-01-01

    We study the kinetics for the search of an immobile target by randomly moving searchers that detect it only upon encounter. The searchers perform intermittent random walks on a one-dimensional lattice. Each searcher can step on a nearest neighbor site with probability α or go off lattice with probability 1 - α to move in a random direction until it lands back on the lattice at a fixed distance L away from the departure point. Considering α and L as optimization parameters, we seek to enhance the chances of successful detection by minimizing the probability P N that the target remains undetected up to the maximal search time N. We show that even in this simple model, a number of very efficient search strategies can lead to a decrease of P N by orders of magnitude upon appropriate choices of α and L. We demonstrate that, in general, such optimal intermittent strategies are much more efficient than Brownian searches and are as efficient as search algorithms based on random walks with heavy-tailed Cauchy jump-length distributions. In addition, such intermittent strategies appear to be more advantageous than Levy-based ones in that they lead to more thorough exploration of visited regions in space and thus lend themselves to parallelization of the search processes.

  15. Human adipocytes are highly sensitive to intermittent hypoxia induced NF-kappaB activity and subsequent inflammatory gene expression

    International Nuclear Information System (INIS)

    Taylor, Cormac T.; Kent, Brian D.; Crinion, Sophie J.; McNicholas, Walter T.; Ryan, Silke

    2014-01-01

    Highlights: • Intermittent hypoxia (IH) leads to NF-κB activation in human primary adipocytes. • Adipocytes bear higher pro-inflammatory potential than other human primary cells. • IH leads to upregulation of multiple pro-inflammatory genes in human adipocytes. - Abstract: Introduction: Intermittent hypoxia (IH)-induced activation of pro-inflammatory pathways is a major contributing factor to the cardiovascular pathophysiology associated with obstructive sleep apnea (OSA). Obesity is commonly associated with OSA although it remains unknown whether adipose tissue is a major source of inflammatory mediators in response to IH. The aim of this study was to test the hypothesis that IH leads to augmented inflammatory responses in human adipocytes when compared to cells of non-adipocyte lineages. Methods and results: Human primary subcutaneous and visceral adipocytes, human primary microvascular pulmonary endothelial cells (HUMEC-L) and human primary small airway epithelial cells (SAEC) were exposed to 0, 6 or 12 cycles of IH or stimulated with tumor necrosis factor (TNF)-α. IH led to a robust increase in NF-κB DNA-binding activity in adipocytes compared with normoxic controls regardless of whether the source of adipocytes was visceral or subcutaneous. Notably, the NF-κB response of adipocytes to both IH and TNF-α was significantly greater than that in HUMEC-L and SAEC. Western blotting confirmed enhanced nuclear translocation of p65 in adipocytes in response to IH, accompanied by phosphorylation of I-κB. Parallel to p65 activation, we observed a significant increase in secretion of the adipokines interleukin (IL)-8, IL-6 and TNF-α with IH in adipocytes accompanied by significant upregulation of mRNA expression. PCR-array suggested profound influence of IH on pro-inflammatory gene expression in adipocytes. Conclusion: Human adipocytes demonstrate strong sensitivity to inflammatory gene expression in response to acute IH and hence, adipose tissue may be a key

  16. Human adipocytes are highly sensitive to intermittent hypoxia induced NF-kappaB activity and subsequent inflammatory gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Cormac T. [School of Medicine and Medical Science, The Conway Institute, University College Dublin (Ireland); Kent, Brian D.; Crinion, Sophie J.; McNicholas, Walter T. [School of Medicine and Medical Science, The Conway Institute, University College Dublin (Ireland); Pulmonary and Sleep Disorders Unit, St. Vincent’s University Hospital, Dublin (Ireland); Ryan, Silke, E-mail: silke.ryan@ucd.ie [School of Medicine and Medical Science, The Conway Institute, University College Dublin (Ireland); Pulmonary and Sleep Disorders Unit, St. Vincent’s University Hospital, Dublin (Ireland)

    2014-05-16

    Highlights: • Intermittent hypoxia (IH) leads to NF-κB activation in human primary adipocytes. • Adipocytes bear higher pro-inflammatory potential than other human primary cells. • IH leads to upregulation of multiple pro-inflammatory genes in human adipocytes. - Abstract: Introduction: Intermittent hypoxia (IH)-induced activation of pro-inflammatory pathways is a major contributing factor to the cardiovascular pathophysiology associated with obstructive sleep apnea (OSA). Obesity is commonly associated with OSA although it remains unknown whether adipose tissue is a major source of inflammatory mediators in response to IH. The aim of this study was to test the hypothesis that IH leads to augmented inflammatory responses in human adipocytes when compared to cells of non-adipocyte lineages. Methods and results: Human primary subcutaneous and visceral adipocytes, human primary microvascular pulmonary endothelial cells (HUMEC-L) and human primary small airway epithelial cells (SAEC) were exposed to 0, 6 or 12 cycles of IH or stimulated with tumor necrosis factor (TNF)-α. IH led to a robust increase in NF-κB DNA-binding activity in adipocytes compared with normoxic controls regardless of whether the source of adipocytes was visceral or subcutaneous. Notably, the NF-κB response of adipocytes to both IH and TNF-α was significantly greater than that in HUMEC-L and SAEC. Western blotting confirmed enhanced nuclear translocation of p65 in adipocytes in response to IH, accompanied by phosphorylation of I-κB. Parallel to p65 activation, we observed a significant increase in secretion of the adipokines interleukin (IL)-8, IL-6 and TNF-α with IH in adipocytes accompanied by significant upregulation of mRNA expression. PCR-array suggested profound influence of IH on pro-inflammatory gene expression in adipocytes. Conclusion: Human adipocytes demonstrate strong sensitivity to inflammatory gene expression in response to acute IH and hence, adipose tissue may be a key

  17. Potential Benefits and Harms of Intermittent Energy Restriction and Intermittent Fasting Amongst Obese, Overweight and Normal Weight Subjects—A Narrative Review of Human and Animal Evidence

    Directory of Open Access Journals (Sweden)

    Michelle Harvie

    2017-01-01

    Full Text Available Intermittent energy restriction (IER has become popular as a means of weight control amongst people who are overweight and obese, and is also undertaken by normal weight people hoping spells of marked energy restriction will optimise their health. This review summarises randomised comparisons of intermittent and isoenergetic continuous energy restriction for weight loss to manage overweight and obesity. It also summarises the potential beneficial or adverse effects of IER on body composition, adipose stores and metabolic effects from human studies, including studies amongst normal weight subjects and relevant animal experimentation. Six small short term (<6 month studies amongst overweight or obese individuals indicate that intermittent energy restriction is equal to continuous restriction for weight loss, with one study reporting greater reductions in body fat, and two studies reporting greater reductions in HOMA insulin resistance in response to IER, with no obvious evidence of harm. Studies amongst normal weight subjects and different animal models highlight the potential beneficial and adverse effects of intermittent compared to continuous energy restriction on ectopic and visceral fat stores, adipocyte size, insulin resistance, and metabolic flexibility. The longer term benefits or harms of IER amongst people who are overweight or obese, and particularly amongst normal weight subjects, is not known and is a priority for further investigation.

  18. Potential Benefits and Harms of Intermittent Energy Restriction and Intermittent Fasting Amongst Obese, Overweight and Normal Weight Subjects-A Narrative Review of Human and Animal Evidence.

    Science.gov (United States)

    Harvie, Michelle; Howell, Anthony

    2017-01-19

    Intermittent energy restriction (IER) has become popular as a means of weight control amongst people who are overweight and obese, and is also undertaken by normal weight people hoping spells of marked energy restriction will optimise their health. This review summarises randomised comparisons of intermittent and isoenergetic continuous energy restriction for weight loss to manage overweight and obesity. It also summarises the potential beneficial or adverse effects of IER on body composition, adipose stores and metabolic effects from human studies, including studies amongst normal weight subjects and relevant animal experimentation. Six small short term (<6 month) studies amongst overweight or obese individuals indicate that intermittent energy restriction is equal to continuous restriction for weight loss, with one study reporting greater reductions in body fat, and two studies reporting greater reductions in HOMA insulin resistance in response to IER, with no obvious evidence of harm. Studies amongst normal weight subjects and different animal models highlight the potential beneficial and adverse effects of intermittent compared to continuous energy restriction on ectopic and visceral fat stores, adipocyte size, insulin resistance, and metabolic flexibility. The longer term benefits or harms of IER amongst people who are overweight or obese, and particularly amongst normal weight subjects, is not known and is a priority for further investigation.

  19. Potential Benefits and Harms of Intermittent Energy Restriction and Intermittent Fasting Amongst Obese, Overweight and Normal Weight Subjects—A Narrative Review of Human and Animal Evidence

    Science.gov (United States)

    Harvie, Michelle; Howell, Anthony

    2017-01-01

    Intermittent energy restriction (IER) has become popular as a means of weight control amongst people who are overweight and obese, and is also undertaken by normal weight people hoping spells of marked energy restriction will optimise their health. This review summarises randomised comparisons of intermittent and isoenergetic continuous energy restriction for weight loss to manage overweight and obesity. It also summarises the potential beneficial or adverse effects of IER on body composition, adipose stores and metabolic effects from human studies, including studies amongst normal weight subjects and relevant animal experimentation. Six small short term (obese individuals indicate that intermittent energy restriction is equal to continuous restriction for weight loss, with one study reporting greater reductions in body fat, and two studies reporting greater reductions in HOMA insulin resistance in response to IER, with no obvious evidence of harm. Studies amongst normal weight subjects and different animal models highlight the potential beneficial and adverse effects of intermittent compared to continuous energy restriction on ectopic and visceral fat stores, adipocyte size, insulin resistance, and metabolic flexibility. The longer term benefits or harms of IER amongst people who are overweight or obese, and particularly amongst normal weight subjects, is not known and is a priority for further investigation. PMID:28106818

  20. The effects of combined glucose-electrolyte and sodium bicarbonate ingestion on prolonged intermittent exercise performance.

    Science.gov (United States)

    Price, Mike James; Cripps, David

    2012-01-01

    This study examined the effects of combined glucose and sodium bicarbonate ingestion prior to intermittent exercise. Ninemales (mean ± s age 25.4 ± 6.6 years, body mass 78.8 ± 12.0 kg, maximal oxygen uptake (VO2 max)) 47.0 ± 7 ml · kg · min(-1)) undertook 4 × 45 min intermittent cycling trials including 15 × 10 s sprints one hour after ingesting placebo (PLA), glucose (CHO), sodium bicarbonate (NaHCO3) or a combined CHO and NaHCO3 solution (COMB). Post ingestion blood pH (7.45 ± 0.03, 7.46 ± 0.03, 7.32 ± 0.05, 7.32 ± 0.01) and bicarbonate (30.3 ± 2.1, 30.7 ± 1.8, 24.2 ± 1.2, 24.0 ± 1.8 mmol · l(-1)) were greater for NaHCO3 and COMB when compared to PLA and CHO, remaining elevated throughout exercise (main effect for trial; P < 0.05). Blood lactate concentration was greatest throughout exercise for NaHCO3 and COMB (main effect for trial; P < 0.05). Blood glucose concentration was greatest 15 min post-ingestion for CHO followed by COMB, NaHCO3 and PLA (7.13 ± 0.60, 5.58 ± 0.75, 4.51 ± 0.56, 4.46 ± 0.59 mmol · l(-1), respectively; P < 0.05). Gastrointestinal distress was lower during COMB compared to NaHCO3 at 15 min post-ingestion (P < 0.05). No differences were observed for sprint performance between trials (P = 1.00). The results of this study suggest that a combined CHO and NaHCO3 beverage reduced gastrointestinal distress and CHO availability but did not improve performance. Although there was no effect on performance an investigation of the effects in more highly trained individuals may be warranted.

  1. Cognitive-Behavioral Therapy for Intermittent Explosive Disorder: A Pilot Randomized Clinical Trial

    Science.gov (United States)

    McCloskey, Michael S.; Noblett, Kurtis L.; Deffenbacher, Jerry L.; Gollan, Jackie K.; Coccaro, Emil F.

    2008-01-01

    No randomized clinical trials have evaluated the efficacy of psychotherapy for intermittent explosive disorder (IED). In the present study, the authors tested the efficacy of 12-week group and individual cognitive-behavioral therapies (adapted from J. L. Deffenbacher & M. McKay, 2000) by comparing them with a wait-list control in a randomized…

  2. Intermittent exotropia surgery: results in different age groups.

    Science.gov (United States)

    Issaho, Dayane Cristine; Wang, Serena Xiaohong; Weakley, David Robert

    2017-01-01

    To report the outcomes in patients undergoing surgical correction of intermittent exotropia and to compare the age at surgery to motor and sensory success. This was a retrospective cohort study. The results of patients with intermittent exotropia treated with surgery over a 4-year period were reviewed. Patients were divided into two groups based on age at first surgery (groups. One hundred thirty-six patients were evaluated, with 67 and 51 patients undergoing surgery before and after the age of 4 years, respectively. The mean age at surgery was 6.8 ± 2.6 years. The reoperation rate for the patients who underwent surgery before 4 years of age was 48% versus 42% for the ones who underwent surgery after this age (p=0.93). Postoperative stereopsis showed an inverse linear association with age at surgery (page, and may even present better motor results than older patients. Postoperative stereoacuity in younger children revealed to be worse than in older children; however, this result is unlikely to be due to inadequate age for surgery, but rather, immaturity for performing the stereopsis test.

  3. Bubble shape in horizontal and near horizontal intermittent flow

    International Nuclear Information System (INIS)

    Gu, Hanyang; Guo, Liejin

    2015-01-01

    Highlights: • The bubble shapes in intermittent flows are presented experimentally. • The nose-tail inversion phenomenon appears at a low Froude number in downward pipe. • Transition from plug to slug flow occurs when the bubble tail changes from staircase pattern to hydraulic jump. - Abstract: This paper presents an experimental study of the shape of isolated bubbles in horizontal and near horizontal intermittent flows. It is found that the shapes of the nose and body of bubble depend on the Froude number defined by gas/liquid mixture velocity in a pipe, whereas the shape of the back of bubble region depends on both the Froude number and bubble length. The photographic studies show that the transition from plug to slug flow occurs when the back of the bubble changes from staircase pattern to hydraulic jump with the increase of the Froude number and bubble length. The effect of pipe inclination on characteristics of bubble is significant: The bubble is inversely located in a downwardly inclined pipe when the Froude number is low, and the transition from plug flow to slug flow in an upward inclined pipe is more ready to occur compared with that in a downwardly inclined pipe

  4. Ultrastructure of medial rectus muscles in patients with intermittent exotropia.

    Science.gov (United States)

    Yao, J; Wang, X; Ren, H; Liu, G; Lu, P

    2016-01-01

    PURPOSE To study the ultrastructure of the medial rectus in patients with intermittent exotropia at different ages.PATIENTS AND METHODS The medial recti were harvested surgically from 20 patients with intermittent exotropia. Patients were divided into adolescent (age18 years, n=10). The normal control group included five patients without strabismus and undergoing eye enucleation. Hematoxylin and eosin staining and transmission electron microscopy were used to visualize the medial recti. Western blot was used to determine the levels of myosin and actin.RESULTS Varying fiber thickness, atrophy, and misalignment of the medial recti were visualized under optical microscope in patients with exotropia. Electron microscopy revealed sarcomere destruction, myofilament disintegration, unclear dark and light bands, collagen proliferation, and fibrosis. The adolescent group manifested significantly higher levels of myosin and actin than the adult group (Pstronger contraction of the medial recti compared with older patients. Our findings suggest that childhood was the appropriate time for surgery as the benefit of the intervention was better than in adulthood.

  5. The activities of current antimalarial drugs on the life cycle stages of Plasmodium: a comparative study with human and rodent parasites.

    Science.gov (United States)

    Delves, Michael; Plouffe, David; Scheurer, Christian; Meister, Stephan; Wittlin, Sergio; Winzeler, Elizabeth A; Sinden, Robert E; Leroy, Didier

    2012-02-01

    Malaria remains a disease of devastating global impact, killing more than 800,000 people every year-the vast majority being children under the age of 5. While effective therapies are available, if malaria is to be eradicated a broader range of small molecule therapeutics that are able to target the liver and the transmissible sexual stages are required. These new medicines are needed both to meet the challenge of malaria eradication and to circumvent resistance. Little is known about the wider stage-specific activities of current antimalarials that were primarily designed to alleviate symptoms of malaria in the blood stage. To overcome this critical gap, we developed assays to measure activity of antimalarials against all life stages of malaria parasites, using a diverse set of human and nonhuman parasite species, including male gamete production (exflagellation) in Plasmodium falciparum, ookinete development in P. berghei, oocyst development in P. berghei and P. falciparum, and the liver stage of P. yoelii. We then compared 50 current and experimental antimalarials in these assays. We show that endoperoxides such as OZ439, a stable synthetic molecule currently in clinical phase IIa trials, are strong inhibitors of gametocyte maturation/gamete formation and impact sporogony; lumefantrine impairs development in the vector; and NPC-1161B, a new 8-aminoquinoline, inhibits sporogony. These data enable objective comparisons of the strengths and weaknesses of each chemical class at targeting each stage of the lifecycle. Noting that the activities of many compounds lie within achievable blood concentrations, these results offer an invaluable guide to decisions regarding which drugs to combine in the next-generation of antimalarial drugs. This study might reveal the potential of life-cycle-wide analyses of drugs for other pathogens with complex life cycles.

  6. Effect of Cold (14° C) vs. Ice (5° C) Water Immersion on Recovery From Intermittent Running Exercise.

    Science.gov (United States)

    Anderson, Daniel; Nunn, James; Tyler, Christopher J

    2018-03-01

    Anderson, D, Nunn, J, and Tyler, CJ. Effect of cold (14° C) vs. ice (5° C) water immersion on recovery from intermittent running exercise. J Strength Cond Res 32(3): 764-771, 2018-The purpose was to compare 14° C (CWI14° C) and 5° C (CWI5° C) cold water immersion after intermittent running. On 3 occasions, 9 male team-sport players undertook 12 minutes of CWI14° C, CWI5° C, or nonimmersed seated recovery (CON) after 45 minutes of intermittent running exercise. Maximal cycling performance and markers of recovery were measured before and in the 0-72 hours after exercise. Peak power output (PPO) was immediately reduced after all interventions (d = 1.8). CWI5° C was more effective at restoring PPO than CWI14° C (d = 0.38) and CON (d = 0.28) 24 hours after exercise, whereas both CON (d = 0.20) and CWI5 (d = 0.37) were more effective than CWI14° C after 48 hours. Cold water immersion (CWI) was more effective than CON at restoring PPO 72 hours after exercise (d = 0.28-0.30). Mean power output (MPO) was higher in CON compared with CWI5° C (d = 0.30) and CWI14° C (d = 0.21), but there was no difference between CWI5° C and CWI14° C (d = 0.08). CWI5° C was more effective than CWI14° C for restoring MPO to baseline levels 24 hours (d = 0.28) and 72 hours (d = 0.28) after exercise; however, CON was more, or equally, effective as CWI5° C and CWI14° C throughout. Lactate and creatine kinase concentrations were unaffected. Perceived muscle soreness remained elevated in CWI5 and CON throughout but was similar to baseline in CWI14° C after 72 hours. In conclusion, repeated bouts of exercise are initially impaired after 5 and 14° C CWI, but PPO may be improved 72 hours after exercise. Cold water immersion is not recommended for acute recovery based on these data. Athletes and coaches should use the time currently allocated to CWI for more effective and alternative recovery modalities.

  7. Life cycle assessment and energy pay-back time of advanced photovoltaic modules: CdTe and CIS compared to poly-Si

    International Nuclear Information System (INIS)

    Raugei, Marco; Bargigli, Silvia; Ulgiati, Sergio

    2007-01-01

    The paper is concerned with the results of a thorough energy and life cycle assessment (LIA) of CdTe and CIS photovoltaic modules. The analysis is based on actual production data, making it one of the very first of its kind to be presented to the scientific community, and therefore especially worthy of attention as a preliminary indication of the future environmental impact that the up-scaling of thin film module production may entail. The analysis is consistent with the recommendations provided by ISO norms 14040 and updates, and makes use of an in-house developed multi-method impact assessment method named SUMMA, which includes resource demand indicators, energy efficiency indicators, and 'downstream' environmental impact indicators. A comparative framework is also provided, wherein electricity produced by thin film systems such as the ones under study is set up against electricity from poly-Si systems and the average European electricity mix. Results clearly show an overall very promising picture for thin film technologies, which are found to be characterised by favourable environmental impact indicators (with special reference to CdTe systems), in spite of their still comparatively lower efficiencies

  8. Comparing sex steroid levels during the annual cycles of rainbow trout (Oncorhynchus mykiss) diploid female (XX) and triploid female (XXX) genotypic sex.

    Science.gov (United States)

    Espinosa, E; Josa, A; Gil, L; Malo, C; Mitjana, O

    2013-02-01

    In this study, the annual cycle of the gonadal steroids testosterone (T), 11-ketotestosterone (11-KT), 17β-estradiol (E2) and 17α, 20β-dihydroxy-4-pregnen-3-one (DHP) was determined using radioimmunoassay and then compared for two populations of rainbow trout, XX diploid females (n = 40) and XXX triploid females (n = 15). In females, E2 and DHP levels were found to be significantly related to body weight (r = 0.22513; p 0.001, respectively). In this group, E2 concentrations peaked in November (25.05 ng/ml), while maximum DHP levels, only measurable from October to April, were attained in February (64.14 ng/ml). No significant differences in hormone ranges related to egg output ability were observed. Finally, sex steroid concentrations were low in the triploid female XXX fish compared to the female XX population. Nevertheless, maximum T (33.85 ng/ml) and 11-KT (32.35 ng/ml) levels were recorded in January, for XXX. The levels for these two hormones are relatively high and are also significantly associated (r = 0.8430; p < 0.0001). Diploid females showed significantly higher levels of E2 than triploids over the 12-month study period. The female triploid fish produced the lowest steroid hormone levels, such that these would be the most suitable for human consumption. © 2012 Blackwell Verlag GmbH.

  9. Fuel cycle

    International Nuclear Information System (INIS)

    Bahm, W.

    1989-01-01

    The situation of the nuclear fuel cycle for LWR type reactors in France and in the Federal Republic of Germany was presented in 14 lectures with the aim to compare the state-of-the-art in both countries. In addition to the momentarily changing fuilds of fuel element development and fueling strategies, the situation of reprocessing, made interesting by some recent developmnts, was portrayed and differences in ultimate waste disposal elucidated. (orig.) [de

  10. Intermittent fasting protects against the deterioration of cognitive function, energy metabolism and dyslipidemia in Alzheimer's disease-induced estrogen deficient rats.

    Science.gov (United States)

    Shin, Bae Kun; Kang, Suna; Kim, Da Sol; Park, Sunmin

    2018-02-01

    Intermittent fasting may be an effective intervention to protect against age-related metabolic disturbances, although it is still controversial. Here, we investigated the effect of intermittent fasting on the deterioration of the metabolism and cognitive functions in rats with estrogen deficiency and its mechanism was also explored. Ovariectomized rats were infused with β-amyloid (25-35; Alzheimer's disease) or β-amyloid (35-25, Non-Alzheimer's disease; normal cognitive function) into the hippocampus. Each group was randomly divided into two sub-groups: one with intermittent fasting and the other fed ad libitum: Alzheimer's disease-ad libitum, Alzheimer's disease-intermittent fasting, Non-Alzheimer's disease-ad libitum, and Non-Alzheimer's disease-intermittent fasting. Rats in the intermittent fasting groups had a restriction of food consumption to a 3-h period every day. Each group included 10 rats and all rats fed a high-fat diet for four weeks. Interestingly, Alzheimer's disease increased tail skin temperature more than Non-Alzheimer's disease and intermittent fasting prevented the increase. Alzheimer's disease reduced bone mineral density in the spine and femur compared to the Non-Alzheimer's disease, whereas bone mineral density in the hip and leg was reduced by intermittent fasting. Fat mass only in the abdomen was decreased by intermittent fasting. Intermittent fasting decreased food intake without changing energy expenditure. Alzheimer's disease increased glucose oxidation, whereas intermittent fasting elevated fat oxidation as a fuel source. Alzheimer's disease and intermittent fasting deteriorated insulin resistance in the fasting state but intermittent fasting decreased serum glucose levels after oral glucose challenge by increasing insulin secretion. Alzheimer's disease deteriorated short and spatial memory function compared to the Non-Alzheimer's disease, whereas intermittent fasting prevented memory loss in comparison to ad libitum. Unexpectedly

  11. Understanding the effects of predictability, duration, and spatial pattern of drying on benthic invertebrate assemblages in two contrasting intermittent streams

    Science.gov (United States)

    von Schiller, Daniel; Barberá, Gonzalo G.; Díaz, Angela M.; Arce, Maria Isabel; del Campo, Rubén; Tockner, Klement

    2018-01-01

    In the present study, we examined the effects of different drying conditions on the composition, structure and function of benthic invertebrate assemblages. We approached this objective by comparing invertebrate assemblages in perennial and intermittent sites along two intermittent Mediterranean streams with contrasting predictability, duration, and spatial patterns of drying: Fuirosos (high predictability, short duration, downstream drying pattern) and Rogativa (low predictability, long duration, patchy drying pattern). Specifically, we quantified the contribution of individual taxa to those differences, the degree of nestedness, and shifts in the composition, structure and function of benthic invertebrate assemblages along flow intermittence gradients. We observed greater effects of drying on the benthic invertebrate composition in Fuirosos than in Rogativa, resulting in a higher dissimilarity of assemblages between perennial and intermittent sites, as well as a lower degree of nestedness. Furthermore, a higher number of biotic metrics related to richness, abundance and biological traits were significantly different between perennial and intermittent sites in Fuirosos, despite a shorter dry period compared to Rogativa. At the same time, slightly different responses were detected during post-drying (autumn) than pre-drying (spring) conditions in this stream. In Rogativa, shifts in benthic invertebrate assemblages along increasing gradients of flow intermittence were found for three metrics (Ephemeroptera, Plecoptera and Trichoptera (EPT) and Odonata, Coleoptera and Heteroptera (OCH) abundances and aerial active dispersal. Furthermore, we demonstrated that combined gradients of dry period duration and distance to nearest perennial reach can generate complex, and different, responses of benthic invertebrate assemblages, depending on the flow intermittence metric. Our study advances the notion that special attention should be paid to the predictability, duration and

  12. How is overland flow produced under intermittent rain? An analysis using plot-scale rainfall simulation on dryland soils

    Science.gov (United States)

    Dunkerley, David

    2018-01-01

    The characteristic intermittency of rainfall includes temporary cessations (hiatuses), as well as periods of very low intensity within more intense events. To understand how these characteristics of rainfall affect overland flow production, rainfall simulations involving repeated cycles of on-off intermittency were carried out on dryland soils in arid western New South Wales, Australia. Periods of rain (10 mm/h) and no-rain were applied in alternation with cycle times from 3 min to 25 min, in experiments lasting 1-1.5 h. Results showed that intermittency could delay the onset of runoff by more than 30 min, reduce the runoff ratio, reduce the peak runoff rate, and reduce the apparent event infiltration rate by 30-45%. When hiatuses in rainfall were longer than 15-20 min, runoff that had resulted from prior rain ceased completely before the recommencement of rain. Results demonstrate that if rainfall intermittency is not accounted for, estimates of infiltrability based on runoff plot data can be systematically in error. Despite the use of intermittent rain, the episodic occurrence of runoff could be predicted successfully by fitting multiple affine Horton infiltration equations, whose changing f0 and Kf coefficients, but uniform values of fc, reflected the redistribution of soil moisture and the change in the infiltrability f during hiatuses in rainfall. The value of fc varied little among the fitted equations, so constituting an affine set of relationships. This new approach provides an alternative to the use of steady-state methods that are common in rainfall simulation experiments and which typically yield only an estimate of fc. The new field results confirm that intermittency affects infiltration and runoff depths and timing at plot scale and on intra-event timescales. Additional work on other soil types, and at other spatial and temporal scales, is needed to test the generality of these findings.

  13. Type I Collagen Synthesis Marker Procollagen I N-Terminal Peptide (PINP) in Prostate Cancer Patients Undergoing Intermittent Androgen Suppression

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, Gerhard, E-mail: gerhard.hamilton@toc.lbg.ac.at; Olszewski-Hamilton, Ulrike [Ludwig Boltzmann Cluster of Translational of Oncology, Nussdorfer Strasse 64, Vienna A-1090 (Austria); Theyer, Gerhard [Hospital Kittsee, Kittsee A-2421, Burgenland (Austria)

    2011-09-15

    Intermittent androgen suppression (IAS) therapy for prostate cancer patients attempts to maintain the hormone dependence of the tumor cells by cycles alternating between androgen suppression (AS) and treatment cessation till a certain prostate-specific antigen (PSA) threshold is reached. Side effects are expected to be reduced, compared to standard continuous androgen suppression (CAS) therapy. The present study examined the effect of IAS on bone metabolism by determinations of serum procollagen I N-terminal peptide (PINP), a biochemical marker of collagen synthesis. A total of 105 treatment cycles of 58 patients with prostate cancer stages ≥pT2 was studied assessing testosterone, PSA and PINP levels at monthly intervals. During phases of AS lasting for up to nine months PSA levels were reversibly reduced, indicating apoptotic regression of the prostatic tumors. Within the first cycle PINP increased at the end of the AS period and peaked in the treatment cessation phase. During the following two cycles a similar pattern was observed for PINP, except a break in collagen synthesis as indicated by low PINP levels in the first months off treatment. Therefore, measurements of the serum PINP concentration indicated increased bone matrix synthesis in response to >6 months of AS, which uninterruptedly continued into the first treatment cessation phase, with a break into each of the following two pauses. In summary, synthesis of bone matrix collagen increases while degradation decreases during off-treatment phases in patients undergoing IAS. Although a direct relationship between bone matrix turnover and risk of fractures is difficult to establish, IAS for treatment of biochemical progression of prostate tumors is expected to reduce osteoporosis in elderly men often at high risk for bone fractures representing a highly suitable patient population for this kind of therapy.

  14. Effects of hydrogen rich water on prolonged intermittent exercise.

    Science.gov (United States)

    Da Ponte, Alessandro; Giovanelli, Nicola; Nigris, Daniele; Lazzer, Stefano

    2018-05-01

    Recent studies showed a positive effect of hydrogen rich water (HRW) intake on acid-base homeostasis at rest. We investigated 2-weeks of HRW intake on repeated sprint performance and acid-base status during prolonged intermittent cycling exercise. In a cross over single-blind protocol, 8 trained male cyclists (age [mean±SD] 41±7 years, body mass 72.3±4.4 kg, height 1.77±0.04 m, maximal oxygen uptake [V̇O2max] 52.6±4.4 mL·kg-1·min-1) were provided daily with 2 liters of placebo normal water (PLA, pH 7.6, oxidation/reduction potential [ORP] +230 mV, free hydrogen content 0 ppb) or HRW (pH 9.8, ORP -180 mV, free Hydrogen 450 ppb). Tests were performed at baseline and after each period of 2 weeks of treatment. The treatments were counter-balanced and the sequence randomized. The 30-minute intermittent cycling trial consisted in 10 3-minute blocks, each one composed by 90 seconds at 40% V̇O2max, 60 seconds at 60% V̇O2max, 16 seconds all out sprint, and 14 seconds active recovery. Oxygen uptake (V̇O2), heart rate and power output were measured during the whole test, while mean and peak power output (PPO), time to peak power and Fatigue Index (FI) were determined during all the 16 seconds sprints. Lactate, pH and bicarbonate (HCO3-) concentrations were determined at rest and after each sprint on blood obtained by an antecubital vein indwelling catheter. In the PLA group, PPO in absolute values decreased significantly at the 8th and 9th of 10 sprints and in relative values, ΔPPO, decreased significantly at 6th, 8th and 9th of 10 sprints (by mean: -12±5%, Pmay help to maintain PPO in repetitive sprints to exhaustion over 30 minutes.

  15. Response of thyroid follicular cells to gamma irradiation compared to proton irradiation. I. Initial characterization of DNA damage, micronucleus formation, apoptosis, cell survival, and cell cycle phase redistribution

    Science.gov (United States)

    Green, L. M.; Murray, D. K.; Bant, A. M.; Kazarians, G.; Moyers, M. F.; Nelson, G. A.; Tran, D. T.

    2001-01-01

    The RBE of protons has been assumed to be equivalent to that of photons. The objective of this study was to determine whether radiation-induced DNA and chromosome damage, apoptosis, cell killing and cell cycling in organized epithelial cells was influenced by radiation quality. Thyroid-stimulating hormone-dependent Fischer rat thyroid cells, established as follicles, were exposed to gamma rays or proton beams delivered acutely over a range of physical doses. Gamma-irradiated cells were able to repair DNA damage relatively rapidly so that by 1 h postirradiation they had approximately 20% fewer exposed 3' ends than their counterparts that had been irradiated with proton beams. The persistence of free ends of DNA in the samples irradiated with the proton beam implies that either more initial breaks or a quantitatively different type of damage had occurred. These results were further supported by an increased frequency of chromosomal damage as measured by the presence of micronuclei. Proton-beam irradiation induced micronuclei at a rate of 2.4% per gray, which at 12 Gy translated to 40% more micronuclei than in comparable gamma-irradiated cultures. The higher rate of micronucleus formation and the presence of larger micronuclei in proton-irradiated cells was further evidence that a qualitatively more severe class of damage had been induced than was induced by gamma rays. Differences in the type of damage produced were detected in the apoptosis assay, wherein a significant lag in the induction of apoptosis occurred after gamma irradiation that did not occur with protons. The more immediate expression of apoptotic cells in the cultures irradiated with the proton beam suggests that the damage inflicted was more severe. Alternatively, the cell cycle checkpoint mechanisms required for recovery from such damage might not have been invoked. Differences based on radiation quality were also evident in the alpha components of cell survival curves (0.05 Gy(-1) for gamma rays, 0

  16. Intermittent hormonal therapy in the treatment of post-irradiation residual/recurrent prostate cancer

    International Nuclear Information System (INIS)

    Williams, Aaron O; Kocherill, Paul G; Wallace, Michelle; Forman, Jeffrey D

    1996-01-01

    Purpose: To evaluate the efficacy and toxicity of intermittent hormonal therapy in the treatment of residual/recurrent prostate cancer. Materials and Methods: Seventeen patients with biochemical evidence of residual/recurrent prostate cancer were initially treated with radiation therapy (RT)(13), neo-adjuvant hormonal therapy and RT (3), or RT following prostatectomy (1). The mean follow-up time was 19.4 months from the initiation of hormonal therapy. Hormonal therapy consisted of an LH-RH agonist alone (7), an anti-androgen alone (1) or a combination of both (9). Hormonal therapy was continued until the prostatic specific antigen (PSA) level became undetectable. IHT was reinstituted when the PSA reached a pre-determined level, usually greater than or equal to 10ng/ml. Results: The mean time from completion of primary treatment to the initiation of hormonal therapy was 32.5 months. The mean PSA at the start of the first cycle of hormonal therapy was 43.9ng/ml, the second cycle, 11.9ng/ml and the third cycle, 24ng/ml. The mean PSA levels at the end of the first and second cycle of hormonal therapy were .48 and .42ng/ml, respectively. No patient has yet completed the third cycle of hormonal therapy. The average duration of hormonal therapy was 10 months for the first cycle and 4 months for the second cycle. The mean intermittent time off hormones were 9.3 months between cycles 1 and 2, and 10 months between cycles 2 and 3. No patient has yet become refractory to hormonal therapy. Currently all patients are alive. All patients experienced hot flashes and decreased libido at varying degrees during treatment. Thirty-five percent experienced gynecomastia. During the intervals between hormonal therapy, most patients reported a decrease in hot flashes. Conclusion: This analysis supplies preliminary evidence that intermittent hormonal therapy is a viable option in patients with biochemical evidence of disease following initial therapy. It is associated with less treatment

  17. Renewable energies: the cost of intermittency

    International Nuclear Information System (INIS)

    Crassous, Renaud; Roques, Fabien

    2013-01-01

    The authors indicate the different adaptations which will be required for the electric system to cope with the intermittency of solar and wind energy production, and propose an approximate assessment of the associated costs. Different types of adaptation are addressed: secure production in case of absence of wind or sun (electricity imports, construction of additional power stations), use of more flexible production means (gas turbines), grid extensions (connection to offshore production sites, routing of production one part of the country to the other). They think that beyond a 20 per cent share for renewable energies, these costs could rapidly increase

  18. Spatio-temporal intermittency on the sandpile

    International Nuclear Information System (INIS)

    Erzan, A.; Sinha, S.

    1990-08-01

    The self-organized critical state exhibited by a sandpile model is shown to correspond to motion on an attractor characterized by an invariant distribution of the height variable. The largest Lyapunov exponent is equal to zero. The model nonetheless displays intermittent chaos, with a multifractal distribution of local expansion coefficients in history space. Laminar spatio-temporal regions are interrupted by chaotic bursts caused by avalanches. We introduce the concept of local histories in configuration space and show that their expansion parameters also exhibit a multifractal distribution in time and space. (author). 22 refs, 5 figs

  19. Intermittent claudication in a professional rugby player.

    Science.gov (United States)

    Bray, A E; Lewis, W A

    1992-04-01

    Intermittent claudication in a professional rugby player is described. The typical features of a delayed and difficult diagnosis of an external iliac artery stenosis were found. The noninvasive diagnostic protocol used to investigate this young patient with a minimal arterial lesion enabled accurate localization and angioplasty to be performed at the same time as diagnostic angiography. The patient was symptom free with normal arterial pressures on follow-up. It is suggested that appropriate noninvasive investigations should be performed before angiography in young people with minimal lesions.

  20. A stochastic model for intermittent search strategies

    International Nuclear Information System (INIS)

    Benichou, O; Coppey, M; Moreau, M; Suet, P H; Voituriez, R

    2005-01-01

    It is often necessary, in scientific or everyday life problems, to find a randomly hidden target. What is then the optimal strategy to reach it as rapidly as possible? In this article, we develop a stochastic theory for intermittent search behaviours, which are often observed: the searcher alternates phases of intensive search and slow motion with fast displacements. The first results of this theory have already been announced recently. Here we provide a detailed presentation of the theory, as well as the full derivation of the results. Furthermore, we explicitly discuss the minimization of the time needed to find the target

  1. Comparing the sustainability impacts of solar thermal and natural gas combined cycle for electricity production in Mexico: Accounting for decision makers' priorities

    Science.gov (United States)

    Rodríguez-Serrano, Irene; Caldés, Natalia; Oltra, Christian; Sala, Roser

    2017-06-01

    The aim of this paper is to conduct a comprehensive sustainability assessment of the electricity generation with two alternative electricity generation technologies by estimating its economic, environmental and social impacts through the "Framework for Integrated Sustainability Assessment" (FISA). Based on a Multiregional Input Output (MRIO) model linked to a social risk database (Social Hotspot Database), the framework accounts for up to fifteen impacts across the three sustainability pillars along the supply chain of the electricity production from Solar Thermal Electricity (STE) and Natural Gas Combined Cycle (NGCC) technologies in Mexico. Except for value creation, results show larger negative impacts for NGCC, particularly in the environmental pillar. Next, these impacts are transformed into "Aggregated Sustainability Endpoints" (ASE points) as a way to support the decision making in selecting the best sustainable project. ASE points obtained are later compared to the resulting points weighted by the reported priorities of Mexican decision makers in the energy sector obtained from a questionnaire survey. The comparison shows that NGCC achieves a 1.94 times worse negative score than STE, but after incorporating decision makerś priorities, the ratio increases to 2.06 due to the relevance given to environmental impacts such as photochemical oxidants formation and climate change potential, as well as social risks like human rights risks.

  2. An environmental life cycle assessment comparing Australian sugarcane with US corn and UK sugar beet as producers of sugars for fermentation

    International Nuclear Information System (INIS)

    Renouf, M.A.; Wegener, M.K.; Nielsen, L.K.

    2008-01-01

    Sugarcane is a highly suitable substrate for the production of bio-products. As well as producing high yields of sugar, much of the plant's fibre is also recovered and used as a source of renewable energy. A life cycle assessment (LCA) of sugarcane production and processing in Australia was performed to develop an environmental profile of sugarcane as a source of bio-products. The application examined was fermentation products from sugar. The sugarcane results were compared with results for other sugar producing crops-US corn and UK sugar beet-to gauge its relative environmental performance. The results show sugarcane to have an advantage in respect of energy input, greenhouse gas emissions and possibly acidification potential due to its high saccharide yield and the displacement of fossil fuels with surplus renewable energy from cane fibre (bagasse). However Australian sugarcane can exhibit high nitrous oxide emissions, which would reduce greenhouse gas advantages in some regions. For eutrophication, sugar beet provides advantages due to the avoided production of other agricultural crops displaced by the use of beet pulp as an animal feed. The three factors found to have the most influence on the environmental impacts of these agro-industrial systems were the commodities displaced by by-products, agricultural yields, and nitrogen use efficiency

  3. An environmental life cycle assessment comparing Australian sugarcane with US corn and UK sugar beet as producers of sugars for fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Renouf, M.A. [School of Geography, Planning and Architecture, The University of Queensland, Brisbane, QLD 4072 (Australia); CRC for Sugar Industry Innovation through Biotechnology, The University of Queensland, Brisbane, QLD 4072 (Australia); Wegener, M.K. [School of Natural and Rural Systems Management, The University of Queensland, QLD 4072 (Australia); CRC for Sugar Industry Innovation through Biotechnology, The University of Queensland, Brisbane, QLD 4072 (Australia); Nielsen, L.K. [Australian Institute of Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD 4072 (Australia); CRC for Sugar Industry Innovation through Biotechnology, The University of Queensland, Brisbane, QLD 4072 (Australia)

    2008-12-15

    Sugarcane is a highly suitable substrate for the production of bio-products. As well as producing high yields of sugar, much of the plant's fibre is also recovered and used as a source of renewable energy. A life cycle assessment (LCA) of sugarcane production and processing in Australia was performed to develop an environmental profile of sugarcane as a source of bio-products. The application examined was fermentation products from sugar. The sugarcane results were compared with results for other sugar producing crops - US corn and UK sugar beet - to gauge its relative environmental performance. The results show sugarcane to have an advantage in respect of energy input, greenhouse gas emissions and possibly acidification potential due to its high saccharide yield and the displacement of fossil fuels with surplus renewable energy from cane fibre (bagasse). However Australian sugarcane can exhibit high nitrous oxide emissions, which would reduce greenhouse gas advantages in some regions. For eutrophication, sugar beet provides advantages due to the avoided production of other agricultural crops displaced by the use of beet pulp as an animal feed. The three factors found to have the most influence on the environmental impacts of these agro-industrial systems were the commodities displaced by by-products, agricultural yields, and nitrogen use efficiency. (author)

  4. Intermittent fasting and cardiovascular disease: current evidence and unresolved questions.

    Science.gov (United States)

    Tinsley, Grant M; Horne, Benjamin D

    2018-01-01

    Intermittent fasting has produced a variety of beneficial health effects in animal models, although high-quality research in humans has been limited. This special report examines current evidences for intermittent fasting in humans, discusses issues that require further examination, and recommends new research that can improve the knowledge base in this emerging research area. While potentially useful for health improvement, intermittent fasting requires further study prior to widespread implementation for health purposes. Randomized, longer-term studies are needed to determine whether using intermittent fasting as a lifestyle rather than a diet is feasible and beneficial for the health of some members of the human population.

  5. Atomistic Model of Fluorescence Intermittency of Colloidal Quantum Dots

    KAUST Repository

    Voznyy, O.; Sargent, E. H.

    2014-01-01

    with foreign cations can stabilize the vacancies, inhibiting intermittency and improving quantum yield, providing an explanation of recent experimental observations. © 2014 American Physical Society.

  6. A Comparative Study of the Eruptive and Non-eruptive Flares Produced by the Largest Active Region of Solar Cycle 24

    Science.gov (United States)

    Sarkar, Ranadeep; Srivastava, Nandita

    2018-02-01

    We investigate the morphological and magnetic characteristics of solar active region (AR) NOAA 12192. AR 12192 was the largest region of Solar Cycle 24; it underwent noticeable growth and produced 6 X-class flares, 22 M-class flares, and 53 C-class flares in the course of its disc passage. However, the most peculiar fact of this AR is that it was associated with only one CME in spite of producing several X-class flares. In this work, we carry out a comparative study between the eruptive and non-eruptive flares produced by AR 12192. We find that the magnitude of abrupt and permanent changes in the horizontal magnetic field and Lorentz force are significantly smaller in the case of the confined flares compared to the eruptive one. We present the areal evolution of AR 12192 during its disc passage. We find the flare-related morphological changes to be weaker during the confined flares, whereas the eruptive flare exhibits a rapid and permanent disappearance of penumbral area away from the magnetic neutral line after the flare. Furthermore, from the extrapolated non-linear force-free magnetic field, we examine the overlying coronal magnetic environment over the eruptive and non-eruptive zones of the AR. We find that the critical decay index for the onset of torus instability was achieved at a lower height over the eruptive flaring region, than for the non-eruptive core area. These results suggest that the decay rate of the gradient of overlying magnetic-field strength may play a decisive role to determine the CME productivity of the AR. In addition, the magnitude of changes in the flare-related magnetic characteristics are found to be well correlated with the nature of solar eruptions.

  7. Bioenergy and bioproducts from municipal organic waste as alternative to landfilling: a comparative life cycle assessment with prospective application to Mexico.

    Science.gov (United States)

    Escamilla-Alvarado, Carlos; Poggi-Varaldo, Héctor M; Ponce-Noyola, M Teresa

    2017-11-01

    A life cycle assessment (LCA) of a four-stage biorefinery concept, coined H-M-Z-S, that converts 1 t of organic fraction of municipal solid waste (OFMSW) into bioenergy and bioproducts was performed in order to determine whether it could be an alternative to common disposal of OFMSW in landfills in the Mexican reality. The OFMSW is first fermented for hydrogen production, then the fermentates are distributed 40 % to the methane production, 40 % to enzyme production, and 20 % to the saccharification stage. From hydrogen and methane, up to 267 MJ and 204 kWh of gross heat and electricity were produced. The biorefinery proved to be self-sustainable in terms of power (95 kWh net power), but it presented a deficit of energy for heating services (-155 MJ), which was partially alleviated by digesting the wastes from the bioproducts stages (-84 MJ). Compared to landfill, biorefinery showed lower environmental impacts in global warming (down to -128 kg CO 2 -eq), ozone layer depletion (2.96 × 10 -6  kg CFC 11 -eq), and photochemical oxidation potentials (0.011 kg C 2 H 4 -eq). The landfarming of the digestates increased significantly the eutrophication impacts, up to 20 % below the eutrophication from landfilling (1.425 kg PO 4 -eq). These results suggest that H-M-Z-S biorefinery could be an attractive alternative compared to conventional landfilling for the management of municipal solid wastes, although new alternatives and uses of co-products and wastes should be explored and tested. Moreover, the biorefinery system would benefit from the integration into the market chain of the bioproducts, i.e., enzymes and hydrolysates among others.

  8. Comparative Evaluation of Integrated Waste Heat Utilization Systems for Coal-Fired Power Plants Based on In-Depth Boiler-Turbine Integration and Organic Rankine Cycle

    Directory of Open Access Journals (Sweden)

    Shengwei Huang

    2018-01-01

    Full Text Available To maximize the system-level heat integration, three retrofit concepts of waste heat recovery via organic Rankine cycle (ORC, in-depth boiler-turbine integration, and coupling of both are proposed, analyzed and comprehensively compared in terms of thermodynamic and economic performances. For thermodynamic analysis, exergy analysis is employed with grand composite curves illustrated to identify how the systems are fundamentally and quantitatively improved, and to highlight key processes for system improvement. For economic analysis, annual revenue and investment payback period are calculated based on the estimation of capital investment of each component to identify the economic feasibility and competitiveness of each retrofit concept proposed. The results show that the in-depth boiler-turbine integration achieves a better temperature match of heat flows involved for different fluids and multi-stage air preheating, thus a significant improvement of power output (23.99 MW, which is much larger than that of the system with only ORC (6.49 MW. This is mainly due to the limitation of the ultra-low temperature (from 135 to 75 °C heat available from the flue gas for ORC. The thermodynamic improvement is mostly contributed by the reduction of exergy destruction within the boiler subsystem, which is eventually converted to mechanical power; while the exergy destruction within the turbine system is almost not changed for the three concepts. The selection of ORC working fluids is performed to maximize the power output. Due to the low-grade heat source, the cycle with R11 offers the largest additional net power generation but is not significantly better than the other preselected working fluids. Economically, the in-depth boiler-turbine integration is the most economic completive solution with a payback period of only 0.78 year. The ORC concept is less attractive for a sole application due to a long payback time (2.26 years. However, by coupling both

  9. The effects of short work vs. longer work periods within intermittent exercise on V̇o2p kinetics, muscle deoxygenation, and energy system contribution.

    Science.gov (United States)

    McCrudden, Michael C; Keir, Daniel A; Belfry, Glen R

    2017-06-01

    We examined the effects of inserting 3-s recovery periods during high-intensity cycling exercise at 25-s and 10-s intervals on pulmonary oxygen uptake (V̇o 2p ), muscle deoxygenation [deoxyhemoglobin (HHb)], their associated kinetics (τ), and energy system contributions. Eleven men (24 ± 3 yr) completed two trials of three cycling protocols: an 8-min continuous protocol (CONT) and two 8-min intermittent exercise protocols with work-to-rest periods of 25 s to 3 s (25INT) and 10 s to 3 s (10INT). Each protocol began with a step-transition from a 20-W baseline to a power output (PO) of 60% between lactate threshold and maximal V̇o 2p (Δ60). This PO was maintained for 8 min in CONT, whereas 3-s periods of 20-W cycling were inserted every 10 s and 25 s after the transition to Δ60 in 10INT and 25INT, respectively. Breath-by-breath gas exchange measured by mass spectrometry and turbine and vastus lateralis [HHb] measured by near-infrared spectroscopy were recorded throughout. Arterialized-capillary lactate concentration ([Lac - ]) was obtained before and 2 min postexercise. The τV̇o 2p was lowest ( P 0.05) between conditions. Postexercise [Lac - ] was lowest ( P exercise speeded V̇o 2p kinetics and reduced overall V̇o 2p , suggesting an increased reliance on PCr-derived phosphorylation during the work period of INT compared with an identical PO performed continuously. NEW & NOTEWORTHY We report novel observations on the effects of differing heavy-intensity work durations between 3-s recovery periods on pulmonary oxygen uptake (V̇o 2p ) kinetics, muscle deoxygenation, and energy system contributions. Relative to continuous exercise, V̇o 2p kinetics are faster in intermittent exercise, and increased frequency of 3-s recovery periods improves microvascular O 2 delivery and reduces V̇o 2p and arterialized-capillary lactate concentration. The metabolic burden of identical intensity work is altered when performed intermittently vs. continuously. Copyright

  10. Red cell survival and sequestration in acute intermittent porphyria

    International Nuclear Information System (INIS)

    Nawalkha, P.L.; Soni, S.G.; Agrawal, V.K.; Misra, S.N.

    1980-01-01

    Life span and sequestration of red cells have been studied in twenty one proved cases of acute intermittent porphyria of different age and sex group from Bikaner District, Rajasthan State (India). Chromium-51 labelled red cells were used in the study and the excess count method of Bughe Jones and Szur was used to calculate the index of sequestration. The mean apparent half survival time of erythrocytes in the control subjects was 25.9 +- 2.9 (S.D.) days and the same in the prophyria patients was 27.0 +- 3.8 days. This shows that the life span of red cells is normal in both the patient and the control. Excess destruction of red blood cells was found to take place in either spleen or liver in the disease and no excess accumulation of erythrocytes occurred over spleen as compared to liver. (M.G.B.)

  11. An intermittency model for predicting roughness induced transition

    Science.gov (United States)

    Ge, Xuan; Durbin, Paul

    2014-11-01

    An extended model for roughness-induced transition is proposed based on an intermittency transport equation for RANS modeling formulated in local variables. To predict roughness effects in the fully turbulent boundary layer, published boundary conditions for k and ω are used, which depend on the equivalent sand grain roughness height, and account for the effective displacement of wall distance origin. Similarly in our approach, wall distance in the transition model for smooth surfaces is modified by an effective origin, which depends on roughness. Flat plate test cases are computed to show that the proposed model is able to predict the transition onset in agreement with a data correlation of transition location versus roughness height, Reynolds number, and inlet turbulence intensity. Experimental data for a turbine cascade are compared with the predicted results to validate the applicability of the proposed model. Supported by NSF Award Number 1228195.

  12. Chaos as an intermittently forced linear system.

    Science.gov (United States)

    Brunton, Steven L; Brunton, Bingni W; Proctor, Joshua L; Kaiser, Eurika; Kutz, J Nathan

    2017-05-30

    Understanding the interplay of order and disorder in chaos is a central challenge in modern quantitative science. Approximate linear representations of nonlinear dynamics have long been sought, driving considerable interest in Koopman theory. We present a universal, data-driven decomposition of chaos as an intermittently forced linear system. This work combines delay embedding and Koopman theory to decompose chaotic dynamics into a linear model in the leading delay coordinates with forcing by low-energy delay coordinates; this is called the Hankel alternative view of Koopman (HAVOK) analysis. This analysis is applied to the Lorenz system and real-world examples including Earth's magnetic field reversal and measles outbreaks. In each case, forcing statistics are non-Gaussian, with long tails corresponding to rare intermittent forcing that precedes switching and bursting phenomena. The forcing activity demarcates coherent phase space regions where the dynamics are approximately linear from those that are strongly nonlinear.The huge amount of data generated in fields like neuroscience or finance calls for effective strategies that mine data to reveal underlying dynamics. Here Brunton et al.develop a data-driven technique to analyze chaotic systems and predict their dynamics in terms of a forced linear model.

  13. Transient analysis of intermittent multijet sprays

    Energy Technology Data Exchange (ETDEWEB)

    Panao, Miguel R.O.; Moreira, Antonio Luis N. [Universidade Tecnica de Lisboa, IN, Center for Innovation, Technology and Policy Research, Instituto Superior Tecnico, Lisboa (Portugal); Durao, Diamantino G. [Universidade Lusiada, Lisboa (Portugal)

    2012-07-15

    This paper analyzes the transient characteristics of intermittent sprays produced by the single-point impact of multiple cylindrical jets. The aim is to perform a transient analysis of the intermittent atomization process to study the effect of varying the number of impinging jets in the hydrodynamic mechanisms of droplet formation. The results evidence that hydrodynamic mechanisms underlying the physics of ligament fragmentation in 2-impinging jets sprays also apply to sprays produced with more than 2 jets during the main period of injection. Ligaments detaching from the liquid sheet, as well as from its bounding rim, have been identified and associated with distinct droplet clusters, which become more evident as the number of impinging jets increases. Droplets produced by detached ligaments constitute the main spray, and their axial velocity becomes more uniformly distributed with 4-impinging jets because of a delayed ligament fragmentation. Multijet spray dispersion patterns are geometric depending on the number of impinging jets. Finally, an analysis on the Weber number of droplets suggests that multijet sprays are more likely to deposit on interposed surfaces, thus becoming a promising and competitive atomization solution for improving spray cooling. (orig.)

  14. Impact of intermittent fasting on glucose homeostasis.

    Science.gov (United States)

    Varady, Krista A

    2016-07-01

    This article provides an overview of the most recent human trials that have examined the impact of intermittent fasting on glucose homeostasis. Our literature search retrieved one human trial of alternate day fasting, and three trials of Ramadan fasting published in the past 12 months. Current evidence suggests that 8 weeks of alternate day fasting that produces mild weight loss (4% from baseline) has no effect on glucose homeostasis. As for Ramadan fasting, decreases in fasting glucose, insulin, and insulin resistance have been noted after 4 weeks in healthy normal weight individuals with mild weight loss (1-2% from baseline). However, Ramadan fasting may have little impact on glucoregulatory parameters in women with polycystic ovarian syndrome who failed to observe weight loss. Whether intermittent fasting is an effective means of regulating glucose homeostasis remains unclear because of the scarcity of studies in this area. Large-scale, longer-term randomized controlled trials will be required before the use of fasting can be recommended for the prevention and treatment of metabolic diseases.

  15. Intermittency Statistics in the Expanding Solar Wind

    Science.gov (United States)

    Cuesta, M. E.; Parashar, T. N.; Matthaeus, W. H.

    2017-12-01

    The solar wind is observed to be turbulent. One of the open questions in solar wind research is how the turbulence evolves as the solar wind expands to great distances. Some studies have focused on evolution of the outer scale but not much has been done to understand how intermittency evolves in the expanding wind beyond 1 AU (see [1,2]). We use magnetic field data from Voyager I spacecraft from 1 to 10AU to study the evolution of statistics of magnetic discontinuities. We perform various statistical tests on these discontinuities and make connections to the physical processes occurring in the expanding wind.[1] Tsurutani, Bruce T., and Edward J. Smith. "Interplanetary discontinuities: Temporal variations and the radial gradient from 1 to 8.5 AU." Journal of Geophysical Research: Space Physics 84.A6 (1979): 2773-2787.[2] Greco, A., et al. "Evidence for nonlinear development of magnetohydrodynamic scale intermittency in the inner heliosphere." The Astrophysical Journal 749.2 (2012): 105.

  16. Intermittent preventive treatment of malaria in pregnancy

    DEFF Research Database (Denmark)

    Mbonye, A.K.; Bygbjerg, Ib Christian; Magnussen, Pascal

    2008-01-01

    OBJECTIVE: To assess whether traditional birth attendants, drug-shop vendors, community reproductive-health workers, or adolescent peer mobilizers could administer intermittent preventive treatment (IPTp) for malaria with sulfadoxine-pyrimethamine to pregnant women. METHODS: A non-randomized comm......OBJECTIVE: To assess whether traditional birth attendants, drug-shop vendors, community reproductive-health workers, or adolescent peer mobilizers could administer intermittent preventive treatment (IPTp) for malaria with sulfadoxine-pyrimethamine to pregnant women. METHODS: A non......-randomized community trial was implemented in 21 community clusters (intervention) and four clusters where health units provided routine IPTp (control). The primary outcome measures were access and adherence to IPTp, number of malaria episodes, prevalence of anaemia, and birth weight. Numbers of live births, abortions......, still births, and maternal and child deaths were secondary endpoints. FINDINGS: 1404 (67.5%) of 2081 with the new delivery system received two doses of sulfadoxine-pyrimethamine versus 281 (39.9%) of 704 with health units (P malaria episodes decreased from 906 (49...

  17. Intermittent hyperthyreosis. A heat stress syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Sulman, F G; Tal, E; Pfeifer, Y; Superstine, E [Hebrew Univ., Jerusalem (Israel). Dept. of Applied Pharmacology

    1975-09-01

    Intermittent hyperthyreosis occurs under various forms of stress, especially heat stress. The clinician may diagnose such cases as masked or apathetic hyperthyroidism or 'forme fruste' hyperthyreosis or thyroid autonomy. As most routine and standard tests may here yield inconsistent results, it is the patients' anamnesis which may provide the clue. Our Bioclimatology Unit has now seen over 100 cases in which thyroid hypersensitivity towards heat was the most prominent syndrome: 10-15% of weather-sensitive patients are affected. The patients complain before or during heat spells of such contradictory symptoms as insomnia, irritability, tension, tachycardia, palpitations, precordial pain, dyspnoe, flushes with sweating or chills, tremor, abdominal pain or diarrhea, polyuria or pollakisuria, weight loss in spite of ravenous appetite, fatigue, exhaustion, depression, adynamia, lack of concentration and confusion. Determination of urinary neurohormones allows a differential diagnosis, intermittent hyperthyreosis being characterized by three cardinal symptoms: tachycardia - every case with more than 80 pulse beats being suspect (not specific); urinary histamine - every case excreting more than 90 ..mu..g/day being suspect. Again the drawback of this test is its lack of specificity, as histamine may also be increased in cases of allergy and spondylitis; urinary thyroxine - every case excreting more than 20 ..mu..g/day T-4 being suspect. This is the only specific test. Therapy should make use of lithium carbonate and betablockers. Propyl thiouracil is rarely required.

  18. Acute Effects of Carbohydrate Supplementation on Intermittent Sports Performance.

    Science.gov (United States)

    Baker, Lindsay B; Rollo, Ian; Stein, Kimberly W; Jeukendrup, Asker E

    2015-07-14

    Intermittent sports (e.g., team sports) are diverse in their rules and regulations but similar in the pattern of play; that is, intermittent high-intensity movements and the execution of sport-specific skills over a prolonged period of time (~1-2 h). Performance during intermittent sports is dependent upon a combination of anaerobic and aerobic energy systems, both of which rely on muscle glycogen and/or blood glucose as an important substrate for energy production. The aims of this paper are to review: (1) potential biological mechanisms by which carbohydrate may impact intermittent sport performance; (2) the acute effects of carbohydrate ingestion on intermittent sport performance, including intermittent high-intensity exercise capacity, sprinting, jumping, skill, change of direction speed, and cognition; and (3) what recommendations can be derived for carbohydrate intake before/during exercise in intermittent sports based on the available evidence. The most researched intermittent sport is soccer but some sport-specific studies have also been conducted in other sports (e.g., rugby, field hockey, basketball, American football, and racquet sports). Carbohydrate ingestion before/during exercise has been shown in most studies to enhance intermittent high-intensity exercise capacity. However, studies have shown mixed results with regards to the acute effects of carbohydrate intake on sprinting, jumping, skill, change of direction speed, and cognition. In most of these studies the amount of carbohydrate consumed was ~30-60 g/h in the form of a 6%-7% carbohydrate solution comprised of sucrose, glucose, and/or maltodextrin. The magnitude of the impact that carbohydrate ingestion has on intermittent sport performance is likely dependent on the carbohydrate status of the individual; that is, carbohydrate ingestion has the greatest impact on performance under circumstances eliciting fatigue and/or hypoglycemia. Accordingly, carbohydrate ingestion before and during a game

  19. Acute Effects of Carbohydrate Supplementation on Intermittent Sports Performance

    Directory of Open Access Journals (Sweden)

    Lindsay B. Baker

    2015-07-01

    Full Text Available Intermittent sports (e.g., team sports are diverse in their rules and regulations but similar in the pattern of play; that is, intermittent high-intensity movements and the execution of sport-specific skills over a prolonged period of time (~1–2 h. Performance during intermittent sports is dependent upon a combination of anaerobic and aerobic energy systems, both of which rely on muscle glycogen and/or blood glucose as an important substrate for energy production. The aims of this paper are to review: (1 potential biological mechanisms by which carbohydrate may impact intermittent sport performance; (2 the acute effects of carbohydrate ingestion on intermittent sport performance, including intermittent high-intensity exercise capacity, sprinting, jumping, skill, change of direction speed, and cognition; and (3 what recommendations can be derived for carbohydrate intake before/during exercise in intermittent sports based on the available evidence. The most researched intermittent sport is soccer but some sport-specific studies have also been conducted in other sports (e.g., rugby, field hockey, basketball, American football, and racquet sports. Carbohydrate ingestion before/during exercise has been shown in most studies to enhance intermittent high-intensity exercise capacity. However, studies have shown mixed results with regards to the acute effects of carbohydrate intake on sprinting, jumping, skill, change of direction speed, and cognition. In most of these studies the amount of carbohydrate consumed was ~30–60 g/h in the form of a 6%–7% carbohydrate solution comprised of sucrose, glucose, and/or maltodextrin. The magnitude of the impact that carbohydrate ingestion has on intermittent sport performance is likely dependent on the carbohydrate status of the individual; that is, carbohydrate ingestion has the greatest impact on performance under circumstances eliciting fatigue and/or hypoglycemia. Accordingly, carbohydrate ingestion before

  20. Comparative study the expression of calcium cycling genes in Bombay duck (Harpadon nehereus and beltfish (Trichiurus lepturus with different swimming activities

    Directory of Open Access Journals (Sweden)

    Hui Zhang

    2017-06-01

    Full Text Available The contraction and relaxation events of the muscle is mediated by the coordination of many important calcium cycling proteins of ryanodine receptor (RYR, troponin C (TNNC, parvalbumin (PVALB, sarcoendoplasmic reticulum calcium transport ATPase (SERCA and calsequestrin (CASQ. In higher vertebrates, the expression level of calcium cycling proteins are positively correlated to the muscle contraction/relaxation ability of the cell. In this study, we used RNAseq to explore the expression profile of calcium cycling genes between two marine fish of Bombay duck (Harpadon nehereus and beltfish (Trichiurus lepturus with poor and robust swimming activities, respectively. We have studied the hypothesis whether the expression level of calcium cycling proteins are also positive correlated to swimming ability in fish. We used Illumina sequencing technology (NextSeq500 to sequence, assemble and annotate the muscle transcriptome of Bombay duck for the first time. A total of 47,752,240 cleaned reads (deposited in NCBI SRA database with accession number of SRX1706379 were obtained from RNA sequencing and 26,288 unigenes (with N50 of 486 bp were obtained after de novo assembling with Trinity software. BLASTX against NR, GO, KEGG and eggNOG databases show 100%, 65%, 26%, 94% and 88% annotation rate, respectively. Comparison of the dominantly expressed unigenes in fish muscle shows calcium cycling gene expression in beltfish (SRX1674471 is 1.4- to 51.6-fold higher than Bombay duck. Among five calcium cycling genes, the fold change results are very significant in CASQ (51.6 fold and PVALB (9.1 fold and both of them are responsive for calcium binding to reduce free calcium concentration in the sarcoendoplasmic reticulum and cytoplasm. In conclusion, we confirmed that the high abundant expression rate of calcium cycling genes in robust swimming fish species. The current muscle transcriptome and identified calcium cycling gene data can provide more insights into the

  1. Comparative life cycle assessment of the integrated generation of solid fuel and biogas from biomass (IFBB) and whole crop digestion (WCD) in Germany

    International Nuclear Information System (INIS)

    Buehle, Lutz; Stuelpnagel, R.; Wachendorf, M.

    2011-01-01

    Today's bioenergy systems are very different in cultivation, conservation, conversion of the biomass as well as in the form of the final energy. The assessment of bioenergy systems concerning environmental impacts is increasingly up for discussion. Future challenges will be the development of procedures which reconcile high-yielding and efficient approaches with environment friendly production. Against this background the system of Integrated Generation of Solid Fuel and Biogas from Biomass (IFBB) was suggested to increase net energy yields over a wide range of energy crops in order to obtain a higher biodiversity in energy crop cultivation. In the IFBB procedure the ensiled biomass is separated into a liquid phase for biogas production and into a solid fraction for combustion. This work is aimed at the assessment of the IFBB system in comparison to whole crop digestion (WCD). The assessment is based on crop production in a double-cropping system where winter rye and maize are grown subsequently within one growing season. The main parameters investigated are the efficiency of the whole process, primary energy and greenhouse gas savings as well as potentials of acidification and eutrophication according to principles of Life Cycle Assessment. The calculation of energy efficiency shows a superiority of the IFBB system due to a mainly thermal use of the biomass. Savings of fossil primary energy average at a similar level, whereas greenhouse gas savings are slightly higher for WCD. Investigations on acidification and eutrophication show that both bioenergy systems caused higher emissions compared to the fossil-based reference technique. (author)

  2. A Comparative Cradle-to-Gate Life Cycle Assessment of Mid-Rise Office Building Construction Alternatives: Laminated Timber or Reinforced Concrete

    Directory of Open Access Journals (Sweden)

    Raymond J. Cole

    2012-07-01

    Full Text Available The objective of this project was to quantify and compare the environmental impacts associated with alternative designs for a typical North American mid-rise office building. Two scenarios were considered; a traditional cast-in-place, reinforced concrete frame and a laminated timber hybrid design, which utilized engineered wood products (cross-laminated timber (CLT and glulam. The boundary of the quantitative analysis was cradle-to-construction site gate and encompassed the structural support system and the building enclosure. Floor plans, elevations, material quantities, and structural loads associated with a five-storey concrete-framed building design were obtained from issued-for-construction drawings. A functionally equivalent, laminated timber hybrid design was conceived, based on Canadian Building Code requirements. Design values for locally produced CLT panels were established from in-house material testing. Primary data collected from a pilot-scale manufacturing facility was used to develop the life cycle inventory for CLT, whereas secondary sources were referenced for other construction materials. The TRACI characterization methodology was employed to translate inventory flows into impact indicators. The results indicated that the laminated timber building design offered a lower environmental impact in 10 of 11 assessment categories. The cradle-to-gate process energy was found to be nearly identical in both design scenarios (3.5 GJ/m2, whereas the cumulative embodied energy (feedstock plus process of construction materials was estimated to be 8.2 and 4.6 GJ/m2 for the timber and concrete designs, respectively; which indicated an increased availability of readily accessible potential energy stored within the building materials of the timber alternative.

  3. The Activities of Current Antimalarial Drugs on the Life Cycle Stages of Plasmodium: A Comparative Study with Human and Rodent Parasites

    Science.gov (United States)

    Delves, Michael; Plouffe, David; Scheurer, Christian; Meister, Stephan; Wittlin, Sergio; Winzeler, Elizabeth A.; Sinden, Robert E.; Leroy, Didier

    2012-01-01

    Background Malaria remains a disease of devastating global impact, killing more than 800,000 people every year—the vast majority being children under the age of 5. While effective therapies are available, if malaria is to be eradicated a broader range of small molecule therapeutics that are able to target the liver and the transmissible sexual stages are required. These new medicines are needed both to meet the challenge of malaria eradication and to circumvent resistance. Methods and Findings Little is known about the wider stage-specific activities of current antimalarials that were primarily designed to alleviate symptoms of malaria in the blood stage. To overcome this critical gap, we developed assays to measure activity of antimalarials against all life stages of malaria parasites, using a diverse set of human and nonhuman parasite species, including male gamete production (exflagellation) in Plasmodium falciparum, ookinete development in P. berghei, oocyst development in P. berghei and P. falciparum, and the liver stage of P. yoelii. We then compared 50 current and experimental antimalarials in these assays. We show that endoperoxides such as OZ439, a stable synthetic molecule currently in clinical phase IIa trials, are strong inhibitors of gametocyte maturation/gamete formation and impact sporogony; lumefantrine impairs development in the vector; and NPC-1161B, a new 8-aminoquinoline, inhibits sporogony. Conclusions These data enable objective comparisons of the strengths and weaknesses of each chemical class at targeting each stage of the lifecycle. Noting that the activities of many compounds lie within achievable blood concentrations, these results offer an invaluable guide to decisions regarding which drugs to combine in the next-generation of antimalarial drugs. This study might reveal the potential of life-cycle–wide analyses of drugs for other pathogens with complex life cycles. Please see later in the article for the Editors' Summary PMID

  4. Statistical parameter characteristics of gas-phase fluctuations for gas-liquid intermittent flow

    Energy Technology Data Exchange (ETDEWEB)

    Matsui, G.; Monji, H.; Takaguchi, M. [Univ. of Tsukuba (Japan)

    1995-09-01

    This study deals with theoretical analysis on the general behaviour of statistical parameters of gas-phase fluctuations and comparison of statistical parameter characteristics for the real void fraction fluctuations measured with those for the wave form modified the real fluctuations. In order to investigate the details of the relation between the behavior of the statistical parameters in real intermittent flow and analytical results obtained from information on the real flow, the distributions of statistical parameters for general fundamental wave form of gas-phase fluctuations are discussed in detail. By modifying the real gas-phase fluctuations to a trapezoidaly wave, the experimental results can be directly compared with the analytical results. The analytical results for intermittent flow show that the wave form parameter, and the total amplitude of void fraction fluctuations, affects strongly on the statistical parameter characteristics. The comparison with experiment using nitrogen gas-water intermittent flow suggests that the parameters of skewness and excess may be better as indicators of flow pattern. That is, the macroscopic nature of intermittent flow can be grasped by the skewness and the excess, and the detailed flow structure may be described by the mean and the standard deviation.

  5. A novel adjustable automated system for inducing chronic intermittent hypoxia in mice.

    Science.gov (United States)

    Polšek, Dora; Bago, Marcel; Živaljić, Marija; Rosenzweig, Ivana; Lacza, Zsombor; Gajović, Srećko

    2017-01-01

    Sleep apnea is a chronic, widely underdiagnosed condition characterized by disruption of sleep architecture and intermittent hypoxia due to short cessations of breathing. It is a major independent risk factor for myocardial infarction, congestive heart failure and stroke as well as one of the rare modifiable risk factors for Alzheimer's Dementia. Reliable animal disease models are needed to understand the link between sleep apnea and the various clinically linked disorders. An automated system for inducing hypoxia was developed, in which the major improvement was the possibility to efficiently adjust the length and intensity of hypoxia in two different periods. The chamber used a small volume of gas allowing for fast exchanges of different oxygen levels. The mice were kept in their cages adapted with the system on the cage lid. As a proof of principle, they were exposed to a three week period of intermittent hypoxia for 8 hours a day, with 90 s intervals of 5, 7% and 21% oxygen to validate the model. Treated (n = 8) and control mice (no hypoxia, n = 7) were handled in the same manner and their hippocampal brain regions compared by histology. The chamber provided a fast, reliable and precise intermittent hypoxia, without inducing noticeable side effects to the animals. The validation experiment showed that apoptotic neurons in the hippocampus were more numerous in the mice exposed to intermittent hypoxia than in the control group, in all tested hippocampal regions (cornu ammonis 1 (CA1) P apnea, which was validated by apoptosis of hippocampal neurons.

  6. Statistical parameter characteristics of gas-phase fluctuations for gas-liquid intermittent flow

    International Nuclear Information System (INIS)

    Matsui, G.; Monji, H.; Takaguchi, M.

    1995-01-01

    This study deals with theoretical analysis on the general behaviour of statistical parameters of gas-phase fluctuations and comparison of statistical parameter characteristics for the real void fraction fluctuations measured with those for the wave form modified the real fluctuations. In order to investigate the details of the relation between the behavior of the statistical parameters in real intermittent flow and analytical results obtained from information on the real flow, the distributions of statistical parameters for general fundamental wave form of gas-phase fluctuations are discussed in detail. By modifying the real gas-phase fluctuations to a trapezoidaly wave, the experimental results can be directly compared with the analytical results. The analytical results for intermittent flow show that the wave form parameter, and the total amplitude of void fraction fluctuations, affects strongly on the statistical parameter characteristics. The comparison with experiment using nitrogen gas-water intermittent flow suggests that the parameters of skewness and excess may be better as indicators of flow pattern. That is, the macroscopic nature of intermittent flow can be grasped by the skewness and the excess, and the detailed flow structure may be described by the mean and the standard deviation

  7. Intermittent, Non Cyclic Severe Mechanical Aortic Valve Regurgitation

    Science.gov (United States)

    Choi, Jong Hyun; Song, Seunghwan; Lee, Myung-Yong

    2013-01-01

    Mechanical aortic prosthesis dysfunction can result from thrombosis or pannus formation. We describe an unusual case of intermittent, non cyclic mechanical aortic prosthesis dysfunction due to pannus formation with thrombus in the absence of systolic restriction of disk excursion, that presented with intermittent severe aortic regurgitation. PMID:24459568

  8. The Comparison of Continuous and Intermittent Enteral Nutrition In Cerebrovascular Patients

    Directory of Open Access Journals (Sweden)

    Levent Güngör

    2011-06-01

    Full Text Available OBJECTIVE: Dysphagia and malnutrition are not so rare in stroke patients, and have an unfavorable influence on recovery. Nutritional support may reduce infections, duration of hospital stay and mortality. However, there is no clear evidence about the modality of nasogastric nutrition. In this study, intermittent and continuous enteral nutrition is compared by means of pulmonary infections and gastrointestinal tolerance, among acute cerebrovascular patients. METHODS: Sixty two acute cerebrovascular patients with dysphagia were included the study. The same volume of nutrition product was infused 4 times daily to 31 patients, and continuously for 24 hours to the remaining 31. After 10 days of follow-up, the rates of pulmonary infections, diarrhea, increased gastric residual volumes, vomiting and tube occlusion were compared between two groups. RESULTS: Twenty patients developed pneumonia (32% and 8 diarrhea (13%. Mortality due to complications associated with tube feeding was 6%. Aspiration and related pneumonia was present in 11 patients in the intermittent nutrition group (35%, and in 9 patients in the continuous nutrition group (29%. The rate of pulmonary infection was not statistically different between two groups (p>0.05. Diarrhea was observed in 7 intermittently fed patients (23%, while was present only in 1 patient (3% in the continuously fed group. Diarrhea was more common in the intermittent nutrition group, just at the statistical border (p=0.05. None of the patients developed tube occlusion, vomiting and gastric retention. The rate of mortality and the interruption of feeding was not significantly different between two groups (p>0.05. CONCLUSION: Diarrhea and pulmonary infections are more prevalent with intermittent tube feeding with respect to continuous enteral nutrition, though the difference is not so conspicuous. The reason may be contamination of the equipments and the feeding solution because of frequent manipulation and

  9. The Comparison of Continuous and Intermittent Enteral Nutrition In Cerebrovascular Patients

    Directory of Open Access Journals (Sweden)

    Levent Güngör

    2011-06-01

    Full Text Available OBJECTIVE: Dysphagia and malnutrition are not so rare in stroke patients, and have an unfavorable influence on recovery. Nutritional support may reduce infections, duration of hospital stay and mortality. However, there is no clear evidence about the modality of nasogastric nutrition. In this study, intermittent and continuous enteral nutrition is compared by means of pulmonary infections and gastrointestinal tolerance, among acute cerebrovascular patients. METHODS: Sixty two acute cerebrovascular patients with dysphagia were included the study. The same volume of nutrition product was infused 4 times daily to 31 patients, and continuously for 24 hours to the remaining 31. After 10 days of follow-up, the rates of pulmonary infections, diarrhea, increased gastric residual volumes, vomiting and tube occlusion were compared between two groups. RESULTS: Twenty patients developed pneumonia (32% and 8 diarrhea (13%. Mortality due to complications associated with tube feeding was 6%. Aspiration and related pneumonia was present in 11 patients in the intermittent nutrition group (35%, and in 9 patients in the continuous nutrition group (29%. The rate of pulmonary infection was not statistically different between two groups (p>0.05. Diarrhea was observed in 7 intermittently fed patients (23%, while was present only in 1 patient (3% in the continuously fed group. Diarrhea was more common in the intermittent nutrition group, just at the statistical border (p=0.05. None of the patients developed tube occlusion, vomiting and gastric retention. The rate of mortality and the interruption of feeding was not significantly different between two groups (p>0.05. CONCLUSION: Diarrhea and pulmonary infections are more prevalent with intermittent tube feeding with respect to continuous enteral nutrition, though the difference is not so conspicuous. The reason may be contamination of the equipments and the feeding solution because of frequent manipulation and

  10. Normobaric, intermittent hypoxia conditioning is cardio- and vasoprotective in rats.

    Science.gov (United States)

    Manukhina, Eugenia B; Belkina, Ludmila M; Terekhina, Olga L; Abramochkin, Denis V; Smirnova, Elena A; Budanova, Olga P; Mallet, Robert T; Downey, H Fred

    2013-12-01

    Favorable versus detrimental cardiovascular responses to intermittent hypoxia conditioning (IHC) are heavily dependent on experimental or pathological conditions, including the duration, frequency and intensity of the hypoxia exposures. Recently, we demonstrated that a program of moderate, normobaric IHC (FIO2 9.5-10% for 5-10 min/cycle, with intervening 4 min normoxia, 5-8 cycles/day for 20 days) in dogs afforded robust cardioprotection against infarction and arrhythmias induced by coronary artery occlusion-reperfusion, but this protection has not been verified in other species. Accordingly, in this investigation cardio- as well as vasoprotection were examined in male Wistar rats completing the normobaric IHC program or a sham program in which the rats continuously breathed atmospheric air. Myocardial ischemia and reperfusion (IR) was imposed by occlusion and reperfusion of the left anterior descending coronary artery in in situ experiments and by subjecting isolated, perfused hearts to global ischemia-reperfusion. Cardiac arrhythmias and myocardial infarct size were quantified in in situ experiments. Endothelial function was evaluated from the relaxation to acetylcholine of norepinephrine-precontracted aortic rings taken from in situ IR experiments, and from the increase in coronary flow produced by acetylcholine in isolated hearts. IHC sharply reduced cardiac arrhythmias during ischemia and decreased infarct size by 43% following IR. Endothelial dysfunction in aorta was marked after IR in sham rats, but not significant in IHC rats. Similar findings were found for the coronary circulations of isolated hearts. These findings support the hypothesis that moderate, normobaric IHC is cardio- and vasoprotective in a rat model of IR.

  11. A neonatal mouse model of intermittent hypoxia associated with features of apnea in premature infants.

    Science.gov (United States)

    Cai, Jun; Tuong, Chi Minh; Gozal, David

    2011-09-15

    A neonatal mouse model of intermittent hypoxia (IH) simulating the recurring hypoxia/reoxygenation episodes of apnea of prematurity (AOP) was developed. C57BL/6 P2 pups were culled for exposure to either intermittent hypoxia or intermittent air as control. The IH paradigms consisted of alternation cycles of 20.9% O2 and either 8.0% or 5.7% O2 every 120 or 140s for 6h a day during daylight hours from day 2 to day 10 postnatally, i.e., roughly equivalent to human brain development in the perinatal period. IH exposures elicited modest to severe decrease in oxygen saturation along with bradycardia in neonatal mice, which were severity-dependent. Hypomyelination in both central and peripheral nervous systems was observed despite the absence of visible growth retardation. The neonatal mouse model of IH in this study partially fulfills the current diagnostic criteria with features of AOP, and provides opportunities to reproduce in rodents some of the pathophysiological changes associated with this disorder, such as alterations in myelination. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Effect of wet and dry cycles on dissolution of relatively insoluble particles containing Pu

    International Nuclear Information System (INIS)

    Mewhinney, J.A.; Eidson, A.F.; Wong, V.A.

    1987-01-01

    Dissolution of gross alpha emitter radioactivity from particles composed of mixed uranium and plutonium oxides or of plutonium dioxide continually immersed in solvent typically display at least a two-phase dissolution pattern. Rapid dissolution of a small fraction of the total particulate mass is followed by much slower dissolution for the majority of the particulate mass. In this study, respirable particles of (U, Pu)O 2 and PuO 2 were subjected to dissolution using an alternate wetting and drying cycle. Particles were continuously immersed in solvent for 4 d and then dried in air for 3 d. This cycle was repeated weekly for 7 wk. Four solvents were used to represent a range of potential environmental conditions and a fifth solvent was used for comparison to other continuous immersion studies. In contrast to dissolution studies involving continuous immersion over periods of two or more weeks that exhibit a three-phase dissolution process, the alternate wet-dry cycling resulted in repetition of the first two phases of the dissolution pattern for each cycle. This led to significantly enhanced dissolution of both particulate materials. The enhancement in total dissolution ranged from two to ten times larger during each wet-dry cycle compared to studies involving continuous immersion. The results indicate a potential need to re-evaluate environmental models of actinide element bioavailability for particulate materials released to environments where wet-dry cycling may be routine, i.e. intermittent rainfall in an otherwise arid climate or in stream beds with intermittent flow

  13. Changes in pulmonary blood flow do not affect gas exchange during intermittent ventilation in resting turtles

    DEFF Research Database (Denmark)

    Wang, Tobias; Hicks, James W.

    2008-01-01

    The breathing pattern of many different air-breathing vertebrates, including lungfish, anuran amphibians, turtles, crocodiles and snakes, is characterized by brief periods of lung ventilation interspersed among apnoeas of variable duration. These intermittent ventilatory cycles are associated...... experimentally. The present study measured pulmonary gas exchange in fully recovered, freely diving turtles, where changes in pulmonary blood flow were prevented by partial occlusion of the pulmonary artery. Prevention of L-R shunt during ventilation did not impair CO2 excretion and overall, oxygen uptake and CO...

  14. Towards an intermittency-friendly energy system

    DEFF Research Database (Denmark)

    Blarke, Morten

    2012-01-01

    Distributed cogeneration has played a key role in the implementation of sustainable energy policies for three decades. However, increasing penetration levels of intermittent renewables is challenging that position. The paradigmatic case of West Denmark indicates that distributed operators...... are capitulating as wind power penetration levels are moving above 25%; some operators are retiring cogeneration units entirely, while other operators are making way for heat-only boilers. This development is jeopardizing the system-wide energy, economic, and environmental benefits that distributed cogeneration...... still has to offer. The solution is for distributed operators to adapt their technology and operational strategies to achieve a better co-existence between cogeneration and wind power. Four options for doing so are analysed including a new concept that integrates a high pressure compression heat pump...

  15. Scale Dependence of Spatiotemporal Intermittence of Rain

    Science.gov (United States)

    Kundu, Prasun K.; Siddani, Ravi K.

    2011-01-01

    It is a common experience that rainfall is intermittent in space and time. This is reflected by the fact that the statistics of area- and/or time-averaged rain rate is described by a mixed distribution with a nonzero probability of having a sharp value zero. In this paper we have explored the dependence of the probability of zero rain on the averaging space and time scales in large multiyear data sets based on radar and rain gauge observations. A stretched exponential fannula fits the observed scale dependence of the zero-rain probability. The proposed formula makes it apparent that the space-time support of the rain field is not quite a set of measure zero as is sometimes supposed. We also give an ex.planation of the observed behavior in tenus of a simple probabilistic model based on the premise that rainfall process has an intrinsic memory.

  16. Beneficial effects of intermittent suction and pressure treatment in intermittent claudication

    DEFF Research Database (Denmark)

    Mehlsen, J; Himmelstrup, H; Himmelstrup, Bodil

    1993-01-01

    administration. The treatment caused significant increments in the ADP thresholds for platelet aggregation, while the effects on fibrinolysis were uncertain. It is concluded that intermittent suction and pressure treatment offers a new approach for conservative treatment of intermittent claudication....... participated in an open trial investigating the possible effects of the treatment on platelet aggregation and fibrinolysis. Pain-free and maximal walking distances were measured on a treadmill, and systolic blood pressure was measured on the upper limb, the ankle, and the first toe bilaterally. The threshold...... for adenosine diphosphate (ADP)-induced platelet aggregation was tested, and the fibrinolytic activity was estimated from the euglobulin clot lysis time. Active treatment resulted in significant improvements in pain-free and maximal walking distances, whereas no changes could be found during placebo...

  17. Efficacy of continuous versus intermittent subglottic secretion drainage in preventing ventilator-associated pneumonia in patients requiring mechanical ventilation: A single-center randomized controlled trial.

    Science.gov (United States)

    Fujimoto, Hiroko; Yamaguchi, Osamu; Hayami, Hajime; Shimosaka, Mika; Tsuboi, Sayaka; Sato, Mitsunori; Takebayashi, Shigeo; Morita, Satoshi; Saito, Mari; Goto, Takahisa; Kurahashi, Kiyoyasu

    2018-03-23

    Aspiration of subglottic secretion is a widely used intervention to prevent ventilator-associated pneumonia (VAP). This study aimed to compare the efficacy of continuous and intermittent subglottic secretion drainage (SSD) in preventing VAP. A single-center randomized controlled trial was conducted on adult postoperative patients who were expected to undergo mechanical ventilation for more than 48 hours. Primary outcome measure was incidence of VAP and secondary outcome measures were length of mechanical ventilation and intensive-care unit (ICU) stay. Fifty-nine patients received continuous SSD, while 60 patients received intermittent SSD. Of these 119 patients, 88 (74%) were excluded and 15 and 16 patients were allocated to receive continuous and intermittent SSD, respectively. VAP was detected in 4 (26.7%) and 7 (43.8%) patients in the continuous and intermittent groups, respectively, (p=0.320). The length of mechanical ventilation was significantly shorter (p=0.034) in the continuous group (99.5±47.1 h) than in the intermittent group (159.9±94.5 h). The length of ICU stay was also shorter (p=0.0097) in the continuous group (6.3±2.1 days) than the intermittent group (9.8±4.8 days). Although continuous SSD did not reduce the incidence of VAP, it reduced the length of mechanical ventilation and ICU stay when compared to intermittent SSD.

  18. [Intermittent Explosive Disorder: A Controversial Diagnosis].

    Science.gov (United States)

    Zapata, Juan Pablo; Palacio, Juan David

    2016-01-01

    Intermittent explosive disorder (IED) is aan externalizing externalising disorder characterized characterised by recurrent aggression episodes. Even though this disorder was described several decades ago, and it carries personal and social consequences, there is little in the medical scientific literature on this. bibliographic production about it is scanty. To perform a conceptualization conceptualisation of this disorder, through the review and bibliometric analysis of the available scientific articles. A search was performed in databases with the english English terms intermittent explosive disorder, impulse disorders control [MeSH], in combination with other terms. A bibliometric analysis in the GoPubMed® search engineer was also performed using all data obtained in the search. was also perfomed. IED prevalence ranges from 1.4% to 7%, it presents more frequently during middle adolescence, and with more noticeable repercussions in men males than in womenfemales. The psychopathological core of IED is the impulsive aggressive behaviour that presents in the form of «attacks» that occurs in response to a lower precipitating stimulus. Scientific publications about IED are few and relatively recent, and the vast majority is provided bycomes from the United States (56.56%), and headed by a single author. This fact highlights the need to replicate the findings described about the IED in order to demonstrate the validity and reliability of its diagnostic criteria. It is possible that doubts about the existence of a diagnosis lead have led to such a scant literature about the IED. Available studies about IED allow have allowed characterizing a group of subjects with episodes of impulsive aggression to be characterised, but this description requires replication in different latitudesneeds to be repeated in different areas. Copyright © 2015 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  19. Intermittent fasting up-regulates Fsp27/Cidec gene expression in white adipose tissue.

    Science.gov (United States)

    Karbowska, Joanna; Kochan, Zdzislaw

    2012-03-01

    Fat-specific protein of 27 kDa (FSP27) is a novel lipid droplet protein that promotes triacylglycerol storage in white adipose tissue (WAT). The regulation of the Fsp27 gene expression in WAT is largely unknown. We investigated the nutritional regulation of FSP27 in WAT. The effects of intermittent fasting (48 d, eight cycles of 3-d fasting and 3-d refeeding), caloric restriction (48 d), fasting-refeeding (3-d fasting and 3-d refeeding), and fasting (3 d) on mRNA expression of FSP27, peroxisome proliferator-activated receptor γ (PPARγ2), CCAAT/enhancer binding protein α (C/EBPα), and M isoform of carnitine palmitoyltransferase 1 (a positive control for PPARγ activation) in epididymal WAT and on serum triacylglycerol, insulin, and leptin levels were determined in Wistar rats. We also determined the effects of PPARγ activation by rosiglitazone or pioglitazone on FSP27 mRNA levels in primary rat adipocytes. Long-term intermittent fasting, in contrast to other dietary manipulations, significantly up-regulated Fsp27 gene expression in WAT. Moreover, in rats subjected to intermittent fasting, serum insulin levels were elevated; PPARγ2 and C/EBPα mRNA expression in WAT was increased, and there was a positive correlation of Fsp27 gene expression with PPARγ2 and C/EBPα mRNA levels. FSP27 mRNA expression was also increased in adipocytes treated with PPARγ agonists. Our study demonstrates that the transcription of the Fsp27 gene in adipose tissue may be induced in response to nutritional stimuli. Furthermore, PPARγ2, C/EBPα, and insulin may be involved in the nutritional regulation of FSP27. Thus intermittent fasting, despite lower caloric intake, may promote triacylglycerol deposition in WAT by increasing the expression of genes involved in lipid storage, such as Fsp27. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Comparison of an Intermittent Hypoxic Exposure Acclimatization Program to Staging at Moderate Altitude on Endurance Performance at 4300 m

    Science.gov (United States)

    2009-10-01

    Endurance Performance at 4300 m 7 - 6 RTO-MP-HFM-181 breakfast volunteers were provided with two commercially available energy bars and fruit juice ...food composition = 510 kcal, 14 gm fat, 65 gm carbohydrate, 32 gm protein) at 1 to 2 hrs prior to the beginning of each of the cycle endurance test...JE, Robinson SR, Skrinar GS, Lewis SF and Sawka MN. Intermittent altitude exposures improve muscular performance at 4,300 m. J Appl Physiol 95

  1. Enhancement of Intermittent Androgen Ablation Therapy by Finasteride Administration in Animal Models

    National Research Council Canada - National Science Library

    Wang, Zhou

    2006-01-01

    .... Intermittent androgen ablation therapy (IAAT) may slow down the development of androgen refractory tumors because intermittent recovery of androgens can induce differentiation of prostatic epithelial cells...

  2. Enhancement of Intermittent Androgen Ablation Therapy by Finasteride Administration in Animal Models

    National Research Council Canada - National Science Library

    Wang, Zhou

    2004-01-01

    .... Intermittent androgen ablation therapy may slow down the development of androgen refractory tumors because intermittent recovery of androgens can induce differentiation of prostatic epithelial cells...

  3. Enhancement of Intermittent Androgen Ablation Therapy by Finasteride Administration in Animal Models

    National Research Council Canada - National Science Library

    Wang, Zhou

    2005-01-01

    .... Intermittent androgen ablation therapy may slow down the development of androgen refractory tumors because intermittent recovery of androgens can induce differentiation of prostatic epithelial cells...

  4. Enhancement of Intermittent Androgen Ablation Therapy by Finasteride Administration in Animal Models

    National Research Council Canada - National Science Library

    Wang, Zhou

    2003-01-01

    .... Intermittent androgen ablation therapy may slow down the development of androgen refractory tumors because intermittent recovery of androgens can induce differentiation of prostatic epithelial cells...

  5. Distributed and micro-generation from biogas and agricultural application of sewage sludge: Comparative environmental performance analysis using life cycle approaches

    International Nuclear Information System (INIS)

    Sadhukhan, Jhuma

    2014-01-01

    Highlights: • 180,000 MJ biogas from 15.87 t sewage sludge supply 1 household electricity per year. • From the highest to the lowest avoided impacts: PEM FC 2 eq./MJ compared to natural gas. • 1 m 3 biogas production from ∼3.2 t sewage sludge AD can save 0.92 m 3 natural gas. • Digested matter causes eutrophication and toxicity potentials. - Abstract: The Feed-In-Tariff scheme in the UK has generated attractive economics in the investment for anaerobic digestion (AD) to convert sewage sludge into biogas and digested sludge for energy and agricultural applications, respectively. The biogas is a source of biomethane to replace natural gas in the gas grid system. Biogas can be utilised to generate combined heat and power (CHP) on-site, at household micro and distributed or community scales. These biogas CHP generation options can replace the equivalent natural gas based CHP generation options. Digested sludge can be transformed into fertiliser for agricultural application replacing inorganic N:P:K fertiliser. Biogas and digested matter yields are inter-dependent: when one increases, the other decreases. Hence, these various options need to be assessed for avoided life cycle impact potentials, to understand where greatest savings lie and in order to rank these options for informed decision making by water industries. To fill a gap in the information available to industry dealing with wastewater, the avoided emissions by various AD based technologies, in primary impact potentials that make a difference between various systems, have been provided in this paper. 1 m 3 biogas can save 0.92 m 3 natural gas. An average UK household (with a demand of 2 kWe) requires 180,000 MJ or 5000 Nm 3 or 4.76 t biogas per year, from 15.87 t sewage sludge processed through AD. The proton exchange membrane fuel cell (PEM FC) is suitable for building micro-generations; micro gas turbine (Micro GT), solid oxide fuel cell (SOFC) and SOFC-GT hybrid are suitable for distributed

  6. Increased MCP-1 gene expression in monocytes of severe OSA patients and under intermittent hypoxia.

    Science.gov (United States)

    Chuang, Li-Pang; Chen, Ning-Hung; Lin, Yuling; Ko, Wen-Shan; Pang, Jong-Hwei S

    2016-03-01

    Obstructive sleep apnea (OSA) is known to be a risk factor of coronary artery disease. Monocyte chemoattractant protein-1 (MCP-1), as a critical factor for monocyte infiltration, is known to play a role in the development of atherosclerosis. This study aimed to investigate the effect of intermittent hypoxia, the hallmark of OSA, on the MCP-1 expression of monocytes. Peripheral blood was sampled from 61 adults enrolled for suspected OSA. RNA was prepared from the isolated monocytes for the analysis of MCP-1. The effect of in vitro intermittent hypoxia on the regulation and function of MCP-1 was investigated on THP-1 monocytic cells and human monocytes. The mRNA and secreted protein levels were investigated by RT/real-time PCR and enzyme-linked immunosorbent assay, respectively. Monocytic MCP-1 gene expression was found to be increased significantly in severe OSA patients. In vitro intermittent hypoxia was demonstrated to increase the mRNA and protein expression levels of MCP-1 dose- and time-dependently in THP-1 monocytic cells. The MCP-1 mRNA expression in monocytes isolated from OSA patient was induced to a much higher level compared to that from normal control. Pre-treatment with inhibitor for p42/44 MAPK or p38 MAPK suppressed the activation of MCP-1 expression by intermittent hypoxia. This is the first study to demonstrate the increase of MCP-1 gene expression in monocytes of severe OSA patients. In addition, monocytic MCP-1 gene expression can be induced under intermittent hypoxia.

  7. Effect of Simulated Intermittent Altitude on the Metabolic and Hematologic Parameters in Streptozotocin Induced Diabetic Rats

    Directory of Open Access Journals (Sweden)

    mehdi Faramoushi

    2016-04-01

    Full Text Available Background & objectives: Type II diabetes is a metabolic disorder accompanied with insulin resistance of the whole body cells and is considered be the fifth cause of death in the world. Adaptation to altitude can lead to tolerance to many diseases. Therefore, the aim of this study was to determine the effect of simulated intermittent altitude on the metabolic and hematologic parameters and liver function in streptozotocin induced diabetic rats. Methods: In the current experimental study, twenty four male Wistar rats weighing 220±20 gr were randomly divided into three groups; normal control group (NC, n=8, diabetic control group (D, n=8 received fat diet for 2 weeks then were injected with streptozotocin (37 mg/kg and diabetic+hypoxia group (D+H, n=8 including diabetic rat exposed to chronic intermittent hypoxia (PiO2≈106 mm Hg, simulated altitude≈3400 m, 14% oxygen for 8 weeks. Diabetic, hematologic and lipid parameters as well as ALT and AST activities were measured in peripheral blood. Results: Our findings showed that intermittent hypoxia significantly decreased serum total cholesterol, LDL ,VLDL and triglyceride in D+H group compared to D group (p<0.05. Serum levels of fasting blood glucose and homeostatic model assessment-insulin resistance HOMA-IR( index and ALT were decreased in D+H group vs. D group p<0.05. Also, hemoglubin and hematocrite level increased in D+H group in comparison to D group p<0.05. No significant difference was detected in red blood cell count in D+H vs. D group. Conclusion: Based on resultant data, it seems that intermittent exposure to hypoxia (simulated to chronic and intermittent lodgement in altitude can be used to control of type 2 diabetes by increasing hemoglobin, decreasing insulin resistance and improving liver function as well as lipid parameters.

  8. Habitat type and dispersal mode underlie the capacity for plant migration across an intermittent seaway.

    Science.gov (United States)

    Worth, J R P; Holland, B R; Beeton, N J; Schönfeld, B; Rossetto, M; Vaillancourt, R E; Jordan, G J

    2017-10-17

    Investigating species distributions across geographic barriers is a commonly utilized method in biogeography to help understand the functional traits that allow plants to disperse successfully. Here the biogeographic pattern analysis approach is extended by using chloroplast DNA whole-genome 'mining' to examine the functional traits that have impacted the dispersal of widespread temperate forest species across an intermittent seaway, the 200 km wide Bass Strait of south-eastern Australia. Multiple, co-distributed species of both dry and wet forests were sampled from five regions on either side of the Strait to obtain insights into past dispersal of these biomes via seed. Using a next-generation sequencing-based pool-seq method, the sharing of single nucleotide polymorphisms (SNPs) was estimated between all five regions in the chloroplast genome. A total of 3335 SNPs were detected in 20 species. SNP sharing patterns between regions provided evidence for significant seed-mediated gene flow across the study area, including across Bass Strait. A higher proportion of shared SNPs in dry forest species, especially those dispersed by birds, compared with wet forest species suggests that dry forest species have undergone greater seed-mediated gene flow across the study region during past climatic oscillations and sea level changes associated with the interglacial/glacial cycles. This finding is consistent with a greater propensity for long-distance dispersal for species of open habitats and proxy evidence that expansive areas of dry vegetation occurred during times of exposure of Bass Strait during glacials. Overall, this study provides novel genetic evidence that habitat type and its interaction with dispersal traits are major influences on dispersal of plants. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  9. Comparing environmental consequences of anaerobic mono- and co-digestion of pig manure to produce bio-energy – A life cycle perspective

    NARCIS (Netherlands)

    Vries, de J.W.; Vinken, T.M.W.J.; Hamelin, L.; Boer, de I.J.M.

    2012-01-01

    The aim of this work was to assess the environmental consequences of anaerobic mono- and co-digestion of pig manure to produce bio-energy, from a life cycle perspective. This included assessing environmental impacts and land use change emissions (LUC) required to replace used co-substrates for

  10. DEMINERALIZATION OF HUMAN DENTIN COMPARED WITH ENAMEL IN A PH-CYCLING APPARATUS WITH A CONSTANT COMPOSITION DURING DE-MINERALIZATION AND REMINERALIZATION PERIODS

    NARCIS (Netherlands)

    HERKSTROTER, FM; WITJES, M; ARENDS, J

    1991-01-01

    A comparison was made between the demineralization of enamel and dentine with and without abraded surfaces. This was done in a pH-cycling experiment for different demineralization/remineralization ratios - in the range from 1:1 to 1:4 - and for different fluoride additions (up to 2 ppm) in solution.

  11. Plasma lipid peroxidation, blood GSH concentration and erythrocyte antioxidant enzymes in menstruating females with ovulatory and anovulatory cycles compared with males

    Directory of Open Access Journals (Sweden)

    G Lutosławska

    2003-12-01

    Full Text Available This study was undertaken to evaluate plasma TBARS and blood GSH concentration and erythrocyte antioxidant enzymes (glutathione peroxidase, catalase and superoxide dismutase in active, regularly menstruating female physical education students with ovulatory and anovulatory menstrual cycles and in their male counterparts. A total of 27 subjects (12 males and 15 females volunteered to participate in the study. All females were regularly menstruating with cycle length between 26-31 days. Plasma progesterone and 17-β-estradiol concentrations were assayed during the 7th-9th and 22nd-25th day of the menstrual cycle. Women with plasma progesterone concentration exceeding 19 nmol•l-1 during the 22nd-25th day were referred to as ovulatory (Group OV; n=7. Women without a peak plasma progesterone concentration were referred to as anovulatory (Group AN; n=8. Blood from male subjects was withdrawn twice - two weeks apart, at their convenience. It was found that the menstrual cycle phases did not affect plasma TBARS and blood glutathione concentration and erythrocyte GPX, CAT and SOD activity. However, erythrocyte GPX activity either in ovulatory or anovulatory women was by about 30% higher than in male subjects. Erythrocyte SOD activity in ovulatory women both in follicular and luteal phase of the menstrual cycle (1557 U/g Hb and 1394.6 U/g Hb, respectively was markedly lower than in men (1951.8 and 1937.7 U/g Hb for blood sampling I and II, respectively. In contrast, erythrocyte SOD activity in anovulatory women (1855.5 U/g Hb and 1745.7 U/g Hb in the follicular and luteal phases, respectively was similar to that found in men. The above data indicated that erythrocyte GPX and SOD activities are sensitive to plasma ovarian hormone concentration. In addition, they suggested that due to higher erythrocyte GPX activity females even with anovulatory menstrual cycles are protected better than males against hydrogen peroxide action. However, lower superoxide

  12. Intermittent hypoxia increases insulin resistance in genetically obese mice.

    Science.gov (United States)

    Polotsky, Vsevolod Y; Li, Jianguo; Punjabi, Naresh M; Rubin, Arnon E; Smith, Philip L; Schwartz, Alan R; O'Donnell, Christopher P

    2003-10-01

    Obstructive sleep apnoea, a syndrome that leads to recurrent intermittent hypoxia, is associated with insulin resistance in obese individuals, but the mechanisms underlying this association remain unknown. We utilized a mouse model to examine the effects of intermittent hypoxia on insulin resistance in lean C57BL/6J mice and leptin-deficient obese (C57BL/6J-Lepob) mice. In lean mice, exposure to intermittent hypoxia for 5 days (short term) resulted in a decrease in fasting blood glucose levels (from 173 +/- 11 mg dl-1 on day 0 to 138 +/- 10 mg dl-1 on day 5, P obese mice, short-term intermittent hypoxia led to a decrease in blood glucose levels accompanied by a 607 +/- 136 % (P intermittent hypoxia was completely abolished by prior leptin infusion. Obese mice exposed to intermittent hypoxia for 12 weeks (long term) developed a time-dependent increase in fasting serum insulin levels (from 3.6 +/- 1.1 ng ml-1 at baseline to 9.8 +/- 1.8 ng ml-1 at week 12, P intermittent hypoxia is dependent on the disruption of leptin pathways.

  13. Putting intelligent structured intermittent auscultation (ISIA) into practice.

    Science.gov (United States)

    Maude, Robyn M; Skinner, Joan P; Foureur, Maralyn J

    2016-06-01

    Fetal monitoring guidelines recommend intermittent auscultation for the monitoring of fetal wellbeing during labour for low-risk women. However, these guidelines are not being translated into practice and low-risk women birthing in institutional maternity units are increasingly exposed to continuous cardiotocographic monitoring, both on admission to hospital and during labour. When continuous fetal monitoring becomes routinised, midwives and obstetricians lose practical skills around intermittent auscultation. To support clinical practice and decision-making around auscultation modality, the intelligent structured intermittent auscultation (ISIA) framework was developed. The purpose of this discussion paper is to describe the application of intelligent structured intermittent auscultation in practice. The intelligent structured intermittent auscultation decision-making framework is a knowledge translation tool that supports the implementation of evidence into practice around the use of intermittent auscultation for fetal heart monitoring for low-risk women during labour. An understanding of the physiology of the materno-utero-placental unit and control of the fetal heart underpin the development of the framework. Intelligent structured intermittent auscultation provides midwives with a robust means of demonstrating their critical thinking and clinical reasoning and supports their understanding of normal physiological birth. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Photoluminescence intermittency of semiconductor quantum dots in dielectric environments

    Energy Technology Data Exchange (ETDEWEB)

    Isaac, A.

    2006-08-11

    The experimental studies presented in this thesis deal with the photoluminescence intermittency of semiconductor quantum dots in different dielectric environments. Detailed analysis of intermittency statistics from single capped CdSe/ZnS, uncapped CdSe and water dispersed CdSe/ZnS QDs in different matrices provide experimental evidence for the model of photoionization with a charge ejected into the surrounding matrix as the source of PL intermittency phenomenon. We propose a self-trapping model to explain the increase of dark state lifetimes with the dielectric constant of the matrix. (orig.)

  15. Intermittent fasting: a "new" historical strategy for controlling seizures?

    Science.gov (United States)

    Hartman, Adam L; Rubenstein, James E; Kossoff, Eric H

    2013-05-01

    In antiquity, fasting was a treatment for epilepsy and a rationale for the ketogenic diet (KD). Preclinical data indicate the KD and intermittent fasting do not share identical anticonvulsant mechanisms. We implemented an intermittent fasting regimen in six children with an incomplete response to a KD. Three patients adhered to the combined intermittent fasting/KD regimen for 2 months and four had transient improvement in seizure control, albeit with some hunger-related adverse reactions. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Intermittent or daily montelukast versus placebo for episodic asthma in children.

    Science.gov (United States)

    Valovirta, Erkka; Boza, Maria L; Robertson, Colin F; Verbruggen, Nadia; Smugar, Steven S; Nelsen, Linda M; Knorr, Barbara A; Reiss, Theodore F; Philip, George; Gurner, Deborah M

    2011-06-01

    No standard, optimal treatment exists for severe intermittent (ie, episodic) asthma in children. However, evidence suggests that both daily and episode-driven montelukast are effective for this phenotype. To assess the regimen-related efficacy of montelukast in treating pediatric episodic asthma. A multicenter, randomized, double-blind, double-dummy, parallel-group, 52-week study was performed in children 6 months to 5 years of age comparing placebo with two regimens of montelukast 4 mg: (1) daily; or (2) episode-driven for 12 days beginning with signs/symptoms consistent with imminent cold or breathing problem. The main outcome measure was the number of asthma episodes (symptoms requiring treatment) culminating in an asthma attack (symptoms requiring physician visit, emergency room visit, corticosteroids, or hospitalization). Five hundred eighty-nine patients were randomized to daily montelukast, 591 to intermittent montelukast, and 591 to placebo. Compared with placebo, no significant difference was seen between daily montelukast (P = .510) or intermittent montelukast (P = .884) in the number of asthma episodes culminating in an asthma attack over 1 year. Daily montelukast reduced symptoms over the 12-day treatment period of asthma episodes compared with placebo (P = .045). Beta-agonist use was reduced with both daily (P = .048) and intermittent montelukast (P = .028) compared with placebo. However, because of prespecified rules for multiplicity adjustments (requiring a positive primary endpoint), statistical significance for secondary endpoints cannot be concluded. All treatments were well tolerated. Montelukast did not reduce the number of asthma episodes culminating in an asthma attack over 1 year in children 6 months to 5 years of age, although numerical improvements occurred in some endpoints. Copyright © 2011 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  17. Intermittent Renewable Management Pilot Phase 2

    Energy Technology Data Exchange (ETDEWEB)

    Kiliccote, Sila [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Homan, Gregory [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Anderson, Robert [Olivine, Inc., San Ramon, CA (United States); Hernandez, John [Pacific Gas & Electric Company, San Francisco, CA (United States)

    2015-04-01

    The Intermittent Renewable Management Pilot - Phase 2 (IRM2) was designed to study the feasibility of demand-side resources to participate into the California Independent System Operator (CAISO) wholesale market as proxy demand resources (PDR). The pilot study focused on understanding the issues related with direct participation of third-parties and customers including customer acceptance; market transformation challenges (wholesale market, technology); technical and operational feasibility; and value to the rate payers, DR resource owners and the utility on providing an enabling mechanism for DR resources into the wholesale markets. The customer had the option of committing to either three contiguous hour blocks for 24 days or six contiguous hours for 12 days a month with day-ahead notification that aligned with the CAISO integrated forward market. As a result of their being available, the customer was paid $10/ kilowatt (kW)-month for capacity in addition to CAISO energy settlements. The participants were limited to no more than a 2 megawatt (MW) capacity with a six-month commitment. Four participants successfully engaged in the pilot. In this report, we provide the description of the pilot, participant performance results, costs and value to participants as well as outline some of the issues encountered through the pilot. Results show that participants chose to participate with storage and the value of CAISO settlements were significantly lower than the capacity payments provided by the utility as incentive payments. In addition, this pilot revealed issues both on the participant side and system operations side. These issues are summarized in the report.The Intermittent Renewable Management Pilot - Phase 2 (IRM2) was designed to study the feasibility of demand-side resources to participate into the California Independent System Operator (CAISO) wholesale market as proxy demand resources (PDR). The pilot study focused on understanding the issues related with

  18. Identification of new ovulation-related genes in humans by comparing the transcriptome of granulosa cells before and after ovulation triggering in the same controlled ovarian stimulation cycle

    DEFF Research Database (Denmark)

    Wissing, M L; Kristensen, S G; Andersen, C Y

    2014-01-01

    . Many new ovulation-related genes were revealed, such as CD24, ANKRD22, CLDN11 and FBXO32. FF estrogen, androstenedione and anti-Müllerian hormone decreased significantly while progesterone increased, accompanied by radical changes in the expression of steroidogenic genes (CYP17A, CYP19A, HSD11B1......, REASONS FOR CAUTION: The present dataset was generated from women under hormonal stimulation. However, comparison with a macaque natural cycle whole follicle ovulation dataset revealed major overlap, supporting the idea that the ovulation-related genes found in this study are relevant in the human natural...... cycle. WIDER IMPLICATIONS OF THE FINDINGS: These data will serve as a research resource for genes involved in human ovulation and final oocyte maturation. Ovulation-related genes might be good candidate biomarkers of follicle and oocyte health. Further, some of the ovulation-related genes may serve...

  19. Intermittent whole-body cold immersion induces similar thermal stress but different motor and cognitive responses between males and females.

    Science.gov (United States)

    Solianik, Rima; Skurvydas, Albertas; Mickevičienė, Dalia; Brazaitis, Marius

    2014-10-01

    The main aim of this study was to compare the thermal responses and the responses of cognitive and motor functions to intermittent cold stress between males and females. The intermittent cold stress continued until rectal temperature (TRE) reached 35.5°C or for a maximum of 170 min. Thermal response and motor and cognitive performance were monitored. During intermittent cold stress, body temperature variables decreased in all subjects (P cold strain index did not differ between sexes. Maximal voluntary contraction (MVC) decreased after intermittent cold exposure only in males (P cold stress on electrically evoked muscle properties, spinal (H-reflex), and supraspinal (V-waves) reflexes did not differ between sexes. Intermittent cold-induced cognitive perturbation of attention and memory task performance was greater in males (P whole-body cold immersion. Although no sex-specific differences were observed in muscle EMG activity, involuntary muscle properties, spinal and supraspinal reflexes, some of the sex differences observed (e.g., lower isometric MVC and greater cognitive perturbation in males) support the view of sex-specific physiological responses to core temperature decrease. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Recovery of Physiological Traits in Saplings of Invasive Bischofia Tree Compared with Three Species Native to the Bonin Islands under Successive Drought and Irrigation Cycles.

    Science.gov (United States)

    Yazaki, Kenichi; Kuroda, Katsushi; Nakano, Takashi; Kitao, Mitsutoshi; Tobita, Hiroyuki; Ogasa, Mayumi Y; Ishida, Atsushi

    2015-01-01

    Partial leaf shedding induced by hydraulic failure under prolonged drought can prevent excess water consumption, resulting in delayed recovery of carbon productivity following rainfall. To understand the manner of water use of invasive species in oceanic island forests under a fluctuating water regime, leaf shedding, multiple physiological traits, and the progress of embolism in the stem xylem under repeated drought-irrigation cycles were examined in the potted saplings of an invasive species, Bischofia javanica Blume, and three endemic native species, Schima mertensiana (Sieb. Et Zucc,) Koitz., Hibiscus glaber Matsum, and Distylium lepidotum Nakai, from the Bonin Islands, Japan. The progress of xylem embolism was observed by cryo-scanning electron microscopy. The samples exhibited different processes of water saving and drought tolerance based on the different combinations of partial leaf shedding involved in embolized conduits following repeated de-rehydration. Predawn leaf water potential largely decreased with each successive drought-irrigation cycle for all tree species, except for B. javanica. B. javanica shed leaves conspicuously under drought and showed responsive stomatal conductance to VPD, which contributed to recover leaf gas exchange in the remaining leaves, following a restored water supply. In contrast, native tree species did not completely recover photosynthetic rates during the repeated drought-irrigation cycles. H. glaber and D. lepidotum preserved water in vessels and adjusted leaf osmotic rates but did not actively shed leaves. S. mertensiana exhibited partial leaf shedding during the first cycle with an osmotic adjustment, but they showed less responsive stomatal conductance to VPD. Our data indicate that invasive B. javanica saplings can effectively use water supplied suddenly under drought conditions. We predict that fluctuating precipitation in the future may change tree distributions even in mesic or moist sites in the Bonin Islands.