Simultaneous multislice echo planar imaging with blipped controlled aliasing in parallel imaging results in higher acceleration: a promising technique for accelerated diffusion tensor imaging of skeletal muscle

OpenAIRE

Filli, Lukas; Piccirelli, Marco; Kenkel, David; Guggenberger, Roman; Andreisek, Gustav; Beck, Thomas; Runge, Val M; Boss, Andreas

2015-01-01

PURPOSE The aim of this study was to investigate the feasibility of accelerated diffusion tensor imaging (DTI) of skeletal muscle using echo planar imaging (EPI) applying simultaneous multislice excitation with a blipped controlled aliasing in parallel imaging results in higher acceleration unaliasing technique. MATERIALS AND METHODS After federal ethics board approval, the lower leg muscles of 8 healthy volunteers (mean [SD] age, 29.4 [2.9] years) were examined in a clinical 3-T magnetic ...

Structured intermittent interruption of chronic HIV infection treatment with highly active antiretroviral therapy: effects on leptin and TNF-alpha.

Science.gov (United States)

Arjona, M Montes de Oca; Pérez-Cano, R; Garcia-Juárez, R; Martín-Aspas, A; del Alamo, C Fernández Gutiérrez; Girón-González, J A

2006-04-01

The changes in nutritional parameters and adipocytokines after structured intermittent interruption of highly active antiretroviral treatment of patients with chronic HIV infection are analyzed. Twenty-seven patients with chronic HIV infection (median CD4+ T cell count/microl: nadir, 394; at the beginning of structured interruptions, 1041; HIV viral load: nadir, 41,521 copies/ml; at the beginning of structured interruptions triglycerides, cholesterol, leptin, and tumor necrosis factor and its soluble receptors I and II were determined. After the three cycles of intermittent interruptions of therapy, no significant differences in CD4+ T cell count/microl, viral load, or serum concentrations of cholesterol or triglycerides with reference to baseline values were found. A near-significant higher fatty mass (skinfold thicknesses, at the end, 121 mm, at the beginning, 100 mm, p = 0.100), combined with a significant increase of concentration of leptin (1.5 vs. 4.7 ng/ml, p = 0,044), as well as a decrease in serum concentrations of soluble receptors of tumor necrosis factor (TNFRI, 104 vs. 73 pg/ml, p = 0.022; TNFRII 253 vs. 195 pg/ml, p = 0.098) were detected. Structured intermittent interruption of highly active antiretroviral treatment of patients with chronic HIV infection induces a valuable positive modification in markers of lipid turnover and adipose tissue mass.

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.

Viral and host factors related with histopathologyc activity in patients with chronic hepatitis B and moderate or intermittently elevated alanine aminotransferase levels Influencia de factores virales y del huésped en la actividad histológica en pacientes con hepatitis crónica por virus de la hepatitis B y elevación moderada o intermitente de alanina aminotransferasa

Directory of Open Access Journals (Sweden)

E. Molina Pérez

2010-09-01

Full Text Available Objective: viral and host factors are related with progression of pathological lesion in chronic hepatitis B. We analyzed these factors in patients with moderate or intermittently elevated ALT levels, and its threshold that determinate significant histological activity. Patients and methods: retrospective analyses of viral and host parameters in 89 consecutive chronic hepatitis B patients biopsied because of moderate or intermittently elevated ALT levels [1-2 x ULN (ULN = 39 IU/mL] and/or DNA-HBV > 2 x 10³ IU/mL in AntiHBe+ patients. It was analyzed age, gender, ALT levels, HBeAg, viral load and genotype. It was considered advanced histological lesion a Knodell Score (KS > 7 and histological lesion indicating treatment, lobular inflammation ≥ 2 or fibrosis ≥ 2 according to Scheuer Classification. Results: KS > 7 and histological lesion indicating treatment was found in 47.8 and 60.7% respectively. It was observed relationship between age, male gender, ALT levels and viral load with histological damage (p ULN (69.1 vs. 47.1%, p = 0.04. There were not significant upper frequencies of advanced lesion when a cut-off of 40 years or DNA-HBV > 2 x 10³ IU/mL viral load or serological status HBeAg was considerate. Histological activity was lesser in genotype D patients than those infected with others genotypes (p Objetivo: analizar factores virales y del huésped relacionados con actividad histológica en un subgrupo de pacientes con hepatitis crónica B y elevación intermitente o moderada de alanina aminotransferasa (ALT, y el umbral que determine daño histológico indicativo de tratamiento. Pacientes y métodos: análisis retrospectivo de parámetros virales y del huésped en 89 pacientes con hepatitis crónica B biopsiados consecutivamente por elevación intermitente o moderada de ALT [1-2 x USN (USN = 39 UI/mL]. Fueron analizados edad, sexo, ALT, HBeAg, carga viral y genotipo. Se consideró como lesion histologica avanzada un Índice de

Intermittent degradation and schizotypy

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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.

Viral asthma: implications for clinical practice

Directory of Open Access Journals (Sweden)

Roger Menendez

2010-07-01

Full Text Available Roger Menendez1, Michael D Goldman21Allergy and Asthma Center of El Paso, El Paso, TX, USA; 2Pulmonary Division, UCLA Gaffen School of Medicine, Los Angeles, CA, USAAbstract: The natural history of asthma appears to be driven primarily by the timing and duration of viral respiratory infections. From the very high rate of infections in childhood, to the more sporadic pattern seen in adults, the cycle of acute injury followed by an inefficient repair process helps explain the clinical patterns of asthma severity currently recognized by asthma guidelines. Why the asthmatic host responds to viral injury in a particular way is largely a mystery and the subject of intense investigation. The role of viruses in asthma extends not just to intermittent but to persistent disease, and to both the atopic as well as nonatopic phenotypes. Future therapeutic strategies should include primary prevention via the development of antiviral innate immunity-enhancing vaccines, as well as secondary prevention via the use of antiviral agents, or immunomodulators designed to boost the antiviral response or interrupt the proinflammatory cascade.Keywords: asthma, rhinoviruses, exacerbations, epidemiology, phenotypes, clinical trials

Angiotensin converting enzyme 1 in the median preoptic nucleus contributes to chronic intermittent hypoxia hypertension.

Science.gov (United States)

Faulk, Katelynn E; Nedungadi, T Prashant; Cunningham, J Thomas

2017-05-01

Obstructive sleep apnea is associated with hypertension and cardiovascular disease. Chronic intermittent hypoxia is used to model the arterial hypoxemia seen in sleep apnea patients and is associated with increased sympathetic nerve activity and a sustained diurnal increase in blood pressure. The renin angiotensin system has been associated with hypertension seen in chronic intermittent hypoxia. Angiotensin converting enzyme 1, which cleaves angiotensin I to the active counterpart angiotensin II, is present within the central nervous system and has been shown to be regulated by AP-1 transcription factors, such as ΔFosB. Our previous study suggested that this transcriptional regulation in the median preoptic nucleus contributes to the sustained blood pressure seen following chronic intermittent hypoxia. Viral mediated delivery of a short hairpin RNA against angiotensin converting enzyme 1 in the median preoptic nucleus was used along with radio-telemetry measurements of blood pressure to test this hypothesis. FosB immunohistochemistry was utilized in order to assess the effects of angiotensin converting enzyme 1 knockdown on the activity of nuclei downstream from median preoptic nucleus. Angiotensin converting enzyme 1 knockdown within median preoptic nucleus significantly attenuated the sustained hypertension seen in chronic intermittent hypoxia. Angiotensin converting enzyme 1 seems to be partly responsible for regulating downstream regions involved in sympathetic and blood pressure control, such as the paraventricular nucleus and the rostral ventrolateral medulla. The data suggest that angiotensin converting enzyme 1 within median preoptic nucleus plays a critical role in the sustained hypertension seen in chronic intermittent hypoxia. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

Intermittent Explosive Disorder

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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.

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.

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

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.)

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.

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.

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.

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

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

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.

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.

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

Selecting for Fast Protein-Protein Association As Demonstrated on a Random TEM1 Yeast Library Binding BLIP.

Science.gov (United States)

Cohen-Khait, Ruth; Schreiber, Gideon

2018-04-27

Protein-protein interactions mediate the vast majority of cellular processes. Though protein interactions obey basic chemical principles also within the cell, the in vivo physiological environment may not allow for equilibrium to be reached. Thus, in vitro measured thermodynamic affinity may not provide a complete picture of protein interactions in the biological context. Binding kinetics composed of the association and dissociation rate constants are relevant and important in the cell. Therefore, changes in protein-protein interaction kinetics have a significant impact on the in vivo activity of the proteins. The common protocol for the selection of tighter binders from a mutant library selects for protein complexes with slower dissociation rate constants. Here we describe a method to specifically select for variants with faster association rate constants by using pre-equilibrium selection, starting from a large random library. Toward this end, we refine the selection conditions of a TEM1-β-lactamase library against its natural nanomolar affinity binder β-lactamase inhibitor protein (BLIP). The optimal selection conditions depend on the ligand concentration and on the incubation time. In addition, we show that a second sort of the library helps to separate signal from noise, resulting in a higher percent of faster binders in the selected library. Fast associating protein variants are of particular interest for drug development and other biotechnological applications.

Pressure Autoregulation Measurement Techniques in Adult Traumatic Brain Injury, Part I: A Scoping Review of Intermittent/Semi-Intermittent Methods.

Science.gov (United States)

Zeiler, Frederick A; Donnelly, Joseph; Calviello, Leanne; Menon, David K; Smielewski, Peter; Czosnyka, Marek

2017-12-01

The purpose of this study was to perform a systematic, scoping review of commonly described intermittent/semi-intermittent autoregulation measurement techniques in adult traumatic brain injury (TBI). Nine separate systematic reviews were conducted for each intermittent technique: computed tomographic perfusion (CTP)/Xenon-CT (Xe-CT), positron emission tomography (PET), magnetic resonance imaging (MRI), arteriovenous difference in oxygen (AVDO 2 ) technique, thigh cuff deflation technique (TCDT), transient hyperemic response test (THRT), orthostatic hypotension test (OHT), mean flow index (Mx), and transfer function autoregulation index (TF-ARI). MEDLINE ® , BIOSIS, EMBASE, Global Health, Scopus, Cochrane Library (inception to December 2016), and reference lists of relevant articles were searched. A two tier filter of references was conducted. The total number of articles utilizing each of the nine searched techniques for intermittent/semi-intermittent autoregulation techniques in adult TBI were: CTP/Xe-CT (10), PET (6), MRI (0), AVDO 2 (10), ARI-based TCDT (9), THRT (6), OHT (3), Mx (17), and TF-ARI (6). The premise behind all of the intermittent techniques is manipulation of systemic blood pressure/blood volume via either chemical (such as vasopressors) or mechanical (such as thigh cuffs or carotid compression) means. Exceptionally, Mx and TF-ARI are based on spontaneous fluctuations of cerebral perfusion pressure (CPP) or mean arterial pressure (MAP). The method for assessing the cerebral circulation during these manipulations varies, with both imaging-based techniques and TCD utilized. Despite the limited literature for intermittent/semi-intermittent techniques in adult TBI (minus Mx), it is important to acknowledge the availability of such tests. They have provided fundamental insight into human autoregulatory capacity, leading to the development of continuous and more commonly applied techniques in the intensive care unit (ICU). Numerous methods of

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

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.

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.

Nucleocapsid-Independent Specific Viral RNA Packaging via Viral Envelope Protein and Viral RNA Signal

OpenAIRE

Narayanan, Krishna; Chen, Chun-Jen; Maeda, Junko; Makino, Shinji

2003-01-01

For any of the enveloped RNA viruses studied to date, recognition of a specific RNA packaging signal by the virus's nucleocapsid (N) protein is the first step described in the process of viral RNA packaging. In the murine coronavirus a selective interaction between the viral transmembrane envelope protein M and the viral ribonucleoprotein complex, composed of N protein and viral RNA containing a short cis-acting RNA element, the packaging signal, determines the selective RNA packaging into vi...

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...

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.

Viral Reservoirs in Lymph Nodes of FIV-Infected Progressor and Long-Term Non-Progressor Cats during the Asymptomatic Phase.

Directory of Open Access Journals (Sweden)

C D Eckstrand

Full Text Available Examination of a cohort of cats experimentally infected with feline immunodeficiency virus (FIV for 5.75 years revealed detectable proviral DNA in peripheral blood mononuclear cells (PBMCs harvested during the asymptomatic phase, undetectable plasma viral RNA (FIV gag, and rarely detectable cell-associated viral RNA. Despite apparent viral latency in peripheral CD4+ T cells, circulating CD4+ T cell numbers progressively declined in progressor animals. The aim of this study was to explore this dichotomy of peripheral blood viral latency in the face of progressive immunopathology. The viral replication status, cellular immunophenotypes, and histopathologic features were compared between popliteal lymph nodes (PLNs and peripheral blood. Also, we identified and further characterized one of the FIV-infected cats identified as a long-term non-progressor (LTNP.PLN-derived leukocytes from FIV-infected cats during the chronic asymptomatic phase demonstrated active viral gag transcription and FIV protein translation as determined by real-time RT-PCR, Western blot and in situ immunohistochemistry, whereas viral RNA in blood leukocytes was either undetectable or intermittently detectable and viral protein was not detected. Active transcription of viral RNA was detectable in PLN-derived CD4+ and CD21+ leukocytes. Replication competent provirus was reactivated ex vivo from PLN-derived leukocytes from three of four FIV-infected cats. Progressor cats showed a persistent and dramatically decreased proportion and absolute count of CD4+ T cells in blood, and a decreased proportion of CD4+ T cells in PLNs. A single long-term non-progressor (LTNP cat persistently demonstrated an absolute peripheral blood CD4+ T cell count indistinguishable from uninfected animals, a lower proviral load in unfractionated blood and PLN leukocytes, and very low amounts of viral RNA in the PLN.Collectively our data indicates that PLNs harbor important reservoirs of ongoing viral

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

Viral Hepatitis

Science.gov (United States)

... Home A-Z Health Topics Viral hepatitis Viral hepatitis > A-Z Health Topics Viral hepatitis (PDF, 90 ... liver. Source: National Cancer Institute Learn more about hepatitis Watch a video. Learn who is at risk ...

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.

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.

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.

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...

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...

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

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.

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.

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

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...

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.

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.

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

Longitudinal dynamics of the HIV-specific B cell response during intermittent treatment of primary HIV infection.

Directory of Open Access Journals (Sweden)

Godelieve J de Bree

Full Text Available Neutralizing antibodies develop in natural HIV-1 infection. Their development often takes several years and may rely on chronic virus exposure. At the same time recent studies show that treatment early in infection may provide opportunities for immune preservation. However, it is unknown how intermittent treatment in early infection affects development of the humoral immune response over time. We investigate the effect of cART in early HIV infection on the properties of the memory B cell compartment following 6 months of cART or in the absence of treatment. The patients included participated in the Primo-SHM trial where patients with an early HIV-1 infection were randomized to no treatment or treatment for 24 or 60 weeks.Primo-SHM trial patients selected for the present study were untreated (n = 23 or treated for 24 weeks (n = 24. Here we investigate memory B cell properties at viral set-point and at a late time point (respectively median 54 and 73 weeks before (re-initiation of treatment.At viral set-point, the memory B cell compartment in treated patients demonstrated significantly lower fractions of antigen-primed, activated, memory B cells (p = 0.006. In contrast to untreated patients, in treated patients the humoral HIV-specific response reached a set point over time. At a transcriptional level, sets of genes that showed enhanced expression in memory B cells at viral setpoint in untreated patients, conversely showed rapid increase of expression of the same genes in treated patients at the late time point.These data suggest that, although the memory B cell compartment is phenotypically preserved until viral setpoint after treatment interruption, the development of the HIV-specific antibody response may benefit from exposure to HIV. The effect of viral exposure on B cell properties is also reflected by longitudinal changes in transcriptional profile in memory B cells over time in early treated patients.

Characterization of intermittency in zooplankton behaviour in turbulence.

Science.gov (United States)

Michalec, François-Gaël; Schmitt, François G; Souissi, Sami; Holzner, Markus

2015-10-01

We consider Lagrangian velocity differences of zooplankters swimming in still water and in turbulence. Using cumulants, we quantify the intermittency properties of their motion recorded using three-dimensional particle tracking velocimetry. Copepods swimming in still water display an intermittent behaviour characterized by a high probability of small velocity increments, and by stretched exponential tails. Low values arise from their steady cruising behaviour while heavy tails result from frequent relocation jumps. In turbulence, we show that at short time scales, the intermittency signature of active copepods clearly differs from that of the underlying flow, and reflects the frequent relocation jumps displayed by these small animals. Despite these differences, we show that copepods swimming in still and turbulent flow belong to the same intermittency class that can be modelled by a log-stable model with non-analytical cumulant generating function. Intermittency in swimming behaviour and relocation jumps may enable copepods to display oriented, collective motion under strong hydrodynamic conditions and thus, may contribute to the formation of zooplankton patches in energetic environments.

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.

Viscous liquid barrier demonstration at the Brookhaven National Laboratory Linac Isotope Producer

International Nuclear Information System (INIS)

Heiser, J.H.; Sullivan, T.; Ludewig, H.; Brower, J.; North-Abbott, M.; Manchester, K.; Zaluski, M.; Penny, G.

2000-01-01

Groundwater monitoring has detected tritium ( 3 H) and 22 Na contamination down gradient from the Brookhaven LINAC Isotope Producer (BLIP), located at Brookhaven National Laboratory (BNL). Site characterization studies indicate that the BLIP is the source of contamination. The highest measured values for 3 H were 52,400 pCi/L recorded less than 100 feet south (down gradient) of the BLIP facility. The BLIP produces radioisotopes that are crucial in nuclear medicine for both research and clinical use. The BLIP also supports research on diagnostic and therapeutic radiopharmaceuticals. During operation a proton beam impinges a target (typically salts encapsulated in stainless steel) to produce the required radioisotopes. The proton beam is completely absorbed prior to reaching the soils surrounding the target shaft. However, secondary neutrons are produced that reach the soil causing activation products to form. Among the longer-lived isotopes of concern are tritium and 22 Na. Both of these isotopes have the potential to negatively impact the groundwater below the BLIP. Several corrective actions have been implemented at the BLIP facility in response to tritium detection in the groundwater. The first actions were to improve surface water management (e.g. storm water down spouts) and the installation of a gunite cap around the BLIP facility. These measures are designed to minimize water flow through the activated soils in the vicinity of BLIP. In conjunction with these improvements, BNL is installing a close-proximity subsurface barrier in the activated soils beneath the BLIP facility. The barrier will prevent water migration through the activated soil zone as well as prevent activation product migration out of the zone. To minimize impacts on the operation of the BLIP requires in-situ barrier installation using low energy techniques that will not disturb the alignment of the BLIP or nearby accelerator beams. BNL chose an innovative barrier technology termed Viscous

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

Effects of Intermittent Fasting, Caloric Restriction, and Ramadan Intermittent Fasting on Cognitive Performance at Rest and During Exercise in Adults.

Science.gov (United States)

Cherif, Anissa; Roelands, Bart; Meeusen, Romain; Chamari, Karim

2016-01-01

The aim of this review was to highlight the potent effects of intermittent fasting on the cognitive performance of athletes at rest and during exercise. Exercise interacts with dietary factors and has a positive effect on brain functioning. Furthermore, physical activity and exercise can favorably influence brain plasticity. Mounting evidence indicates that exercise, in combination with diet, affects the management of energy metabolism and synaptic plasticity by affecting molecular mechanisms through brain-derived neurotrophic factor, an essential neurotrophin that acts at the interface of metabolism and plasticity. The literature has also shown that certain aspects of physical performance and mental health, such as coping and decision-making strategies, can be negatively affected by daylight fasting. However, there are several types of intermittent fasting. These include caloric restriction, which is distinct from fasting and allows subjects to drink water ad libitum while consuming a very low-calorie food intake. Another type is Ramadan intermittent fasting, which is a religious practice of Islam, where healthy adult Muslims do not eat or drink during daylight hours for 1 month. Other religious practices in Islam (Sunna) also encourage Muslims to practice intermittent fasting outside the month of Ramadan. Several cross-sectional and longitudinal studies have shown that intermittent fasting has crucial effects on physical and intellectual performance by affecting various aspects of bodily physiology and biochemistry that could be important for athletic success. Moreover, recent findings revealed that immunological variables are also involved in cognitive functioning and that intermittent fasting might impact the relationship between cytokine expression in the brain and cognitive deficits, including memory deficits.

Photonic integrated circuits unveil crisis-induced intermittency.

Science.gov (United States)

Karsaklian Dal Bosco, Andreas; Akizawa, Yasuhiro; Kanno, Kazutaka; Uchida, Atsushi; Harayama, Takahisa; Yoshimura, Kazuyuki

2016-09-19

We experimentally investigate an intermittent route to chaos in a photonic integrated circuit consisting of a semiconductor laser with time-delayed optical feedback from a short external cavity. The transition from a period-doubling dynamics to a fully-developed chaos reveals a stage intermittently exhibiting these two dynamics. We unveil the bifurcation mechanism underlying this route to chaos by using the Lang-Kobayashi model and demonstrate that the process is based on a phenomenon of attractor expansion initiated by a particular distribution of the local Lyapunov exponents. We emphasize on the crucial importance of the distribution of the steady-state solutions introduced by the time-delayed feedback on the existence of this intermittent dynamics.

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.

Controls on streamflow intermittence in the Colorado Front Range

Science.gov (United States)

Kampf, S. K.; Puntenney, K.; Martin, C.; Weber, R.; Gerlich, J.; Hammond, J. C.; Lefsky, M. A.

2017-12-01

Intermittent streams comprise more than 60% of the channel length in semiarid northern Colorado, yet little is known about their flow magnitude and timing. We used field surveys, stream sensors, and remote sensing to quantify spatial and temporal patterns of streamflow intermittence in the Cache la Poudre basin in 2016-2017. To evaluate potential controls on streamflow intermittence, we delineated the drainage area to each monitored point and quantified the catchment's mean precipitation, temperature, snow persistence, slope, aspect, vegetation type, soil type, and bedrock geology. During the period of study, most streams below 2500 m elevation and drainage areas >1 km2 had perennial flow, whereas nearly all streams with drainage areas <1 km2 had intermittent flow. For the high elevation intermittent streams, stream locations often differed substantially from the locations mapped in standard GIS data products. Initial analyses have identified no clearly quantifiable controls on flow duration of high elevation streams, but field observations indicate subsurface flow paths are important contributors to surface streams.

Dynamical analysis and simulation of a 2-dimensional disease model with convex incidence

Science.gov (United States)

Yu, Pei; Zhang, Wenjing; Wahl, Lindi M.

2016-08-01

In this paper, a previously developed 2-dimensional disease model is studied, which can be used for both epidemiologic modeling and in-host disease modeling. The main attention of this paper is focused on various dynamical behaviors of the system, including Hopf and generalized Hopf bifurcations which yield bistability and tristability, Bogdanov-Takens bifurcation, and homoclinic bifurcation. It is shown that the Bogdanov-Takens bifurcation and homoclinic bifurcation provide a new mechanism for generating disease recurrence, that is, cycles of remission and relapse such as the viral blips observed in HIV infection.

Clinical study of intermittent lock of the temporomandibular joint. Relation to frequency of intermittent lock on clinical examination and magnetic resonance imaging

Energy Technology Data Exchange (ETDEWEB)

Ide, Takashi; Nagai, Itaru; Miyazaki, Akihiro; Yamaguchi, Akira; Kohama, Geniku [Sapporo Medical Univ. (Japan). School of Medicine

2002-03-01

To examine the occurrence of intermittent lock, we investigated the correlation between the frequency of intermittent lock of the temporomandibular joint and magnetic resonance imaging (MRI) findings. The subjects consisted of 25 patients (25 joints) with unilateral intermittent lock who were treated from April 1994 through March 2000 at our department. MRI examination of the joint was performed on the affected side. We divided the patients into two groups: a high-frequency group consisting of 15 patients who had symptoms of intermittent lock every day and a low-frequency group consisting of 10 patients who did not have symptoms every day. The results showed no statistical difference between the two groups in clinical findings such as age, sex, clicking side of the joint, duration of intermittent lock, method of unlocking, muscle pain on palpation, degree of maximal mouth opening, distance between the maxillary and mandibular tooth midline, or the degree of overbite and overjet. However, the two groups differed significantly in the degree of anterior disc displacement as assessed by MRI. (author)

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.

Pharyngitis - viral

Science.gov (United States)

... throat is due to a viral infection. The antibiotics will not help. Using them to treat viral infections helps bacteria become resistant to antibiotics. With some sore throats (such as those caused ...

Lu-Hf isotope constraints on plume-lithosphere interaction during emplacement of the Bushveld Large Igneous Province at 2.06 Ga: Implications for the structure and evolution of the Kaapvaal Craton's lithospheric mantle

Science.gov (United States)

Zirakparvar, N. A.; Mathez, E. A.; Rajesh, H.; Vervoort, J. D.; Choe, S.

2016-12-01

The Bushveld Large Igneous Province (B-LIP) comprises a diverse array of >30 magma bodies that intruded the Kaapvaal Craton at 2.06 Ga. In this talk we use zircon and bulk-rock Lu-Hf isotope data to show that the B-LIP formed in response to the arrival of a plume(s) from the deep mantle. New zircon Hf isotope compositions for four B-LIP bodies yield intrusion-specific average ɛHf (2.06 Ga) values that range from -20.7 ± 2.8 to -2.7 ± 2.8, largely consistent with literature zircon data for other B-LIP intrusions. Bulk-rock solution ɛHf (2.06 Ga) values for a variety of B-LIP intrusions range from -2.1 ± 0.2 to -10.6 ± 0.2. Because the most radiogenic Hf isotope compositions across the entire B-LIP are nearly primordial with an ɛHf (2.06 Ga) close to 0, it is likely that the heat source of the B-LIP was a plume(s) from deep mantle. The Hf isotope data further suggests that individual intrusions in the B-LIP can be grouped into four categories based on their ultimate sources: 1) melts generated in subduction and plume modified continental lithospheric mantle; 2) melts generated by melting of a mafic-ultramafic reservoir composed of older ( 2.7 Ga) plume-related material trapped in the Kaapvaal lithosphere; 3) melts generated in the mid- to upper crust; and 4) melts generated from the 2.06 Ga mantle plume itself. The presence of 2.7 Ga mafic-ultramafic material in the Kaapvaal lithosphere may have acted to strengthen the lithosphere so that it was able to resist being dispered by the arrival of the B-LIP plume at 2.06 Ga. Because the B-LIP extends into a 2.7 Ga aged suture zone between the Kaapvaal and Zimbabwe cratons, it is also possible to understand the role of the lithospheric mantle in producing the Lu-Hf signatures observed in the various B-LIP intrusions as a function of two different types of the continental lithosphere: The very old lithosphere comprising the Kaapvaal Craton and the somewhat younger lithosphere comprising the suture zone. A basic

Viral Meningitis

Science.gov (United States)

... better from treatment such as an antiviral medicine. Antibiotics do not help viral infections, so they are not useful in the treatment of viral meningitis. However, antibiotics do fight bacteria, so they are very important ...

Observation of intermittency in gene expression on cDNA microarrays

CERN Document Server

Peterson, L E

2002-01-01

We used scaled factorial moments to search for intermittency in the log expression ratios (LERs) for thousands of genes spotted on cDNA microarrays (gene chips). Results indicate varying levels of intermittency in gene expression. The observation of intermittency in the data analyzed provides a complimentary handle on moderately expressed genes, generally not tackled by conventional techniques.

Small-world networks exhibit pronounced intermittent synchronization

Science.gov (United States)

Choudhary, Anshul; Mitra, Chiranjit; Kohar, Vivek; Sinha, Sudeshna; Kurths, Jürgen

2017-11-01

We report the phenomenon of temporally intermittently synchronized and desynchronized dynamics in Watts-Strogatz networks of chaotic Rössler oscillators. We consider topologies for which the master stability function (MSF) predicts stable synchronized behaviour, as the rewiring probability (p) is tuned from 0 to 1. MSF essentially utilizes the largest non-zero Lyapunov exponent transversal to the synchronization manifold in making stability considerations, thereby ignoring the other Lyapunov exponents. However, for an N-node networked dynamical system, we observe that the difference in its Lyapunov spectra (corresponding to the N - 1 directions transversal to the synchronization manifold) is crucial and serves as an indicator of the presence of intermittently synchronized behaviour. In addition to the linear stability-based (MSF) analysis, we further provide global stability estimate in terms of the fraction of state-space volume shared by the intermittently synchronized state, as p is varied from 0 to 1. This fraction becomes appreciably large in the small-world regime, which is surprising, since this limit has been otherwise considered optimal for synchronized dynamics. Finally, we characterize the nature of the observed intermittency and its dominance in state-space as network rewiring probability (p) is varied.

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 ...

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

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

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

Degrees-of-Freedom of the MIMO Three-Way Channel with Node-Intermittency

KAUST Repository

Neu, Joachim

2017-08-28

The characterization of fundamental performance bounds of many-to-many communication systems in which participating nodes are active in an intermittent way is one of the major challenges in communication theory. In order to address this issue, we introduce the multiple-input multiple-output (MIMO) three-way channel (3WC) with an intermittent node and study its degrees-of-freedom (DoF) region and sum-DoF. We devise a non-adaptive encoding scheme based on zero-forcing, interference alignment and erasure coding, and show its DoF region (and thus sum-DoF) optimality for non-intermittent 3WCs and its sum-DoF optimality for (node-)intermittent 3WCs. However, we show by example that in general some DoF tuples in the intermittent 3WC can only be achieved by adaptive schemes, such as multi-hop or decode-forward relaying. This shows that non-adaptive encoding is sufficient for the non-intermittent 3WC and for the sum-DoF of intermittent 3WCs, but adaptive encoding is necessary for the DoF region of intermittent 3WCs. Our work contributes to a better understanding of the fundamental limits of multi-way communication systems with intermittency and the impact of adaptation therein.

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.

Factors Relevant to Utility Integration of Intermittent Renewable Technologies

Energy Technology Data Exchange (ETDEWEB)

Wan, Y.; Parsons, B.

1993-08-24

This study assesses factors that utilities must address when they integrate intermittent renewable technologies into their power-supply systems; it also reviews the literature in this area and has a bibliography containing more than 350 listings. Three topics are covered: (1) interface (hardware and design-related interconnection), (2) operability/stability, and (3) planning. This study finds that several commonly held perceptions regarding integration of intermittent renewable energy technologies are not valid. Among fmdings of the study are the following: (1) hardware and system design advances have eliminated most concerns about interface, (2) cost penalties have not occurred at low to moderate penetration levels (and high levels am feasible); and (3) intermittent renewable energy technologies can have capacity values. Obstacles still interfering with intermittent renewable technologies are also indentified.

Factors relevant to utility integration of intermittent renewable technologies

Energy Technology Data Exchange (ETDEWEB)

Wan, Yih-huei; Parsons, B.K.

1993-08-01

This study assesses factors that utilities must address when they integrate intermittent renewable technologies into their power-supply systems; it also reviews the literature in this area and has a bibliography containing more than 350 listings. Three topics are covered: (1) interface (hardware and design-related interconnection), (2) operability/stability, and (3) planning. This study finds that several commonly held perceptions regarding integration of intermittent renewable energy technologies are not valid. Among findings of the study are the following: (1) hardware and system design advances have eliminated most concerns about interface; (2) cost penalties have not occurred at low to moderate penetration levels (and high levels are feasible); and (3) intermittent renewable energy technologies can have capacity values. Obstacles still interfering with intermittent renewable technologies are also identified.

Latency versus persistence or intermittent recurrences: evidence for a latent state of murine cytomegalovirus in the lungs.

Science.gov (United States)

Kurz, S; Steffens, H P; Mayer, A; Harris, J R; Reddehase, M J

1997-04-01

The state of cytomegalovirus (CMV) after the resolution of acute infection is an unsolved problem in CMV research. While the term "latency" is in general use to indicate the maintenance of the viral genome, a formal exclusion of low-level persistent productive infection depends on the sensitivity of the assay for detecting infectious virus. We have improved the method for detecting infectivity by combining centrifugal infection of permissive indicator cells in culture, expansion to an infectious focus, and sensitive detection of immediate-early RNA in the infected cells by reverse transcriptase PCR. A limiting-dilution approach defined the sensitivity of this assay. Infectivity was thereby found to require as few as 2 to 9 virion DNA molecules of murine CMV, whereas the standard measure of infectivity, the PFU, is the equivalent of ca. 500 viral genomes. Since murine CMV forms multicapsid virions in most infected tissues, the genome-to-infectivity ratio is necessarily >1. This assay thus sets a new standard for investigating CMV latency. In mice in which acute infection was resolved, the viral DNA load in the lungs, a known organ site of CMV latency and recurrence, was found to be 1 genome per 40 lung cells, or a total of ca. 1 million genomes. Despite this high load of CMV DNA, infectious virus was not detected with the improved assay, but recurrence was inducible. These data provide evidence against a low-level persistent productive infection and also imply that intermittent spontaneous recurrence is not a frequent event in latently infected lungs.

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

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.

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

Coexistence of intermittencies in the neuronal network of the epileptic brain.

Science.gov (United States)

Koronovskii, Alexey A; Hramov, Alexander E; Grubov, Vadim V; Moskalenko, Olga I; Sitnikova, Evgenia; Pavlov, Alexey N

2016-03-01

Intermittent behavior occurs widely in nature. At present, several types of intermittencies are known and well-studied. However, consideration of intermittency has usually been limited to the analysis of cases when only one certain type of intermittency takes place. In this paper, we report on the temporal behavior of the complex neuronal network in the epileptic brain, when two types of intermittent behavior coexist and alternate with each other. We prove the presence of this phenomenon in physiological experiments with WAG/Rij rats being the model living system of absence epilepsy. In our paper, the deduced theoretical law for distributions of the lengths of laminar phases prescribing the power law with a degree of -2 agrees well with the experimental neurophysiological data.

Sliding Intermittent Control for BAM Neural Networks with Delays

Directory of Open Access Journals (Sweden)

Jianqiang Hu

2013-01-01

Full Text Available This paper addresses the exponential stability problem for a class of delayed bidirectional associative memory (BAM neural networks with delays. A sliding intermittent controller which takes the advantages of the periodically intermittent control idea and the impulsive control scheme is proposed and employed to the delayed BAM system. With the adjustable parameter taking different particular values, such a sliding intermittent control method can comprise several kinds of control schemes as special cases, such as the continuous feedback control, the impulsive control, the periodically intermittent control, and the semi-impulsive control. By using analysis techniques and the Lyapunov function methods, some sufficient criteria are derived for the closed-loop delayed BAM neural networks to be globally exponentially stable. Finally, two illustrative examples are given to show the effectiveness of the proposed control scheme and the obtained theoretical results.

Intermittent intravenous followed by intermittent oral 1 alpha(OH)D3 treatment of secondary hyperparathyroidism in uraemia

DEFF Research Database (Denmark)

Brandi, L; Daugaard, H; Egsmose, C

1996-01-01

OBJECTIVES: To examine whether intermittent oral 1 alpha(OH)D3 treatment of patients on haemodialysis with secondary hyperparathyroidism (HPT) was able to maintain the marked suppression of PTH, which previously had been induced by an intermittent intravenous administration of 1 alpha(OH)D3....... Simultaneously, the effect of the different routes of administration of 1 alpha(OH)D3 on the circulating levels of N- and C-terminal PTH fragments was measured. DESIGN: An open study of patients on chronic haemodialysis. SETTING: Renal division, Rigshospitalet, Copenhagen, Denmark. SUBJECTS: A total of 26...

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

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.)

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

Hepatitis viral aguda

Directory of Open Access Journals (Sweden)

Héctor Rubén Hernández Garcés

1998-10-01

Full Text Available Se realizó una revisión bibliográfica de las hepatitis virales agudas sobre aspectos vinculados a su etiología. Se tuvieron en cuenta además algunos datos epidemiológicos, las formas clínicas más importantes, los exámenes complementarios con especial énfasis en los marcadores virales y el diagnóstico positivoA bibliographical review of acute viral hepatitis was made taking into account those aspects connected with its etiology. Some epidemiological markers, the most important clinical forms, and the complementary examinations with special emphasis on the viral markers and the positive diagnosis were also considered

Virale commercials: de consument als marketeer. Onderzoek naar de redenen waarom consumenten virale commercials doorsturen: hun motieven, de inhoudskenmerken van viral commercials en de mediumcontext waarin virale commercials verschijnen

NARCIS (Netherlands)

Ketelaar, P.E.; Lucassen, P.; Kregting, G.H.J.

2010-01-01

Research into the reasons why consumers pass along viral commercials: their motives, the content characteristics of viral commercials and the medium context in which viral commercials appear. Based on the uses and gratifications perspective this study has determined which motives of consumers,

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

Bovine coronavirus in naturally and experimentally exposed calves; viral shedding and the potential for transmission.

Science.gov (United States)

Oma, Veslemøy Sunniva; Tråvén, Madeleine; Alenius, Stefan; Myrmel, Mette; Stokstad, Maria

2016-06-13

Bovine coronavirus (BCoV) is a widely distributed pathogen, causing disease and economic losses in the cattle industry worldwide. Prevention of virus spread is impeded by a lack of basic knowledge concerning viral shedding and transmission potential in individual animals. The aims of the study were to investigate the duration and quantity of BCoV shedding in feces and nasal secretions related to clinical signs, the presence of virus in blood and tissues and to test the hypothesis that seropositive calves are not infectious to naïve in-contact calves three weeks after BCoV infection. A live animal experiment was conducted, with direct contact between animal groups for 24 h as challenge procedure. Four naïve calves were commingled with a group of six naturally infected calves and sequentially euthanized. Two naïve sentinel calves were commingled with the experimentally exposed group three weeks after exposure. Nasal swabs, feces, blood and tissue samples were analyzed for viral RNA by RT-qPCR, and virus isolation was performed on nasal swabs. Serum was analyzed for BCoV antibodies. The calves showed mild general signs, and the most prominent signs were from the respiratory system. The overall clinical score corresponded well with the shedding of viral RNA the first three weeks after challenge. General depression and cough were the signs that correlated best with shedding of BCoV RNA, while peak respiratory rate and peak rectal temperature appeared more than a week later than the peak shedding. Nasal shedding preceded fecal shedding, and the calves had detectable amounts of viral RNA intermittently in feces through day 35 and in nasal secretions through day 28, however virus isolation was unsuccessful from day six and day 18 from the two calves investigated. Viral RNA was not detected in blood, but was found in lymphatic tissue through day 42 after challenge. Although the calves were shedding BCoV RNA 21 days after infection the sentinel animals were not infected

Intermittent fasting: A “new” historical strategy for controlling seizures?

OpenAIRE

Hartman, Adam L.; Rubenstein, James E.; Kossoff, Eric H.

2012-01-01

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.

Viral Disease Networks?

Science.gov (United States)

Gulbahce, Natali; Yan, Han; Vidal, Marc; Barabasi, Albert-Laszlo

2010-03-01

Viral infections induce multiple perturbations that spread along the links of the biological networks of the host cells. Understanding the impact of these cascading perturbations requires an exhaustive knowledge of the cellular machinery as well as a systems biology approach that reveals how individual components of the cellular system function together. Here we describe an integrative method that provides a new approach to studying virus-human interactions and its correlations with diseases. Our method involves the combined utilization of protein - protein interactions, protein -- DNA interactions, metabolomics and gene - disease associations to build a ``viraldiseasome''. By solely using high-throughput data, we map well-known viral associated diseases and predict new candidate viral diseases. We use microarray data of virus-infected tissues and patient medical history data to further test the implications of the viral diseasome. We apply this method to Epstein-Barr virus and Human Papillomavirus and shed light into molecular development of viral diseases and disease pathways.

Sinusoidal visuomotor tracking: intermittent servo-control or coupled oscillations?

Science.gov (United States)

Russell, D M; Sternad, D

2001-12-01

In visuomotor tasks that involve accuracy demands, small directional changes in the trajectories have been taken as evidence of feedback-based error corrections. In the present study variability, or intermittency, in visuomanual tracking of sinusoidal targets was investigated. Two lines of analyses were pursued: First, the hypothesis that humans fundamentally act as intermittent servo-controllers was re-examined, probing the question of whether discontinuities in the movement trajectory directly imply intermittent control. Second, an alternative hypothesis was evaluated: that rhythmic tracking movements are generated by entrainment between the oscillations of the target and the actor, such that intermittency expresses the degree of stability. In 2 experiments, participants (N = 6 in each experiment) swung 1 of 2 different hand-held pendulums, tracking a rhythmic target that oscillated at different frequencies with a constant amplitude. In 1 line of analyses, the authors tested the intermittency hypothesis by using the typical kinematic error measures and spectral analysis. In a 2nd line, they examined relative phase and its variability, following analyses of rhythmic interlimb coordination. The results showed that visually guided corrective processes play a role, especially for slow movements. Intermittency, assessed as frequency and power components of the movement trajectory, was found to change as a function of both target frequency and the manipulandum's inertia. Support for entrainment was found in conditions in which task frequency was identical to or higher than the effector's eigenfrequency. The results suggest that it is the symmetry between task and effector that determines which behavioral regime is dominant.

Intermittent, noncyclic dysfunction of a mechanical aortic prosthesis by pannus formation.

Science.gov (United States)

Giroux, Sylvie K; Labinaz, Marino X; Grisoli, Dominique; Klug, Andrew P; Veinot, John P; Burwash, Ian G

2010-01-01

Mechanical aortic prosthesis dysfunction can result from thrombosis or pannus formation. Pannus formation usually restricts systolic excursion of the occluding disk, resulting in progressive stenosis of the aortic prosthesis. Intermittent dysfunction of a mechanical aortic prosthesis is usually ascribed to thrombus formation. We describe an unusual case of intermittent, noncyclic dysfunction of a mechanical aortic prosthesis due to pannus formation in the absence of systolic restriction of disk excursion that presented with intermittent massive aortic regurgitation, severe ischemia, and shock. Pannus formation should be considered as a potential cause of acute intermittent severe aortic regurgitation in a patient with a mechanical aortic prosthesis.

Intermittent fasting: A “new” historical strategy for controlling seizures?

Science.gov (United States)

Hartman, Adam L.; Rubenstein, James E.; Kossoff, Eric H.

2013-01-01

Summary 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. PMID:23206889

Quantifying spatial and temporal patterns of flow intermittency using spatially contiguous runoff data

Science.gov (United States)

Yu (于松延), Songyan; Bond, Nick R.; Bunn, Stuart E.; Xu, Zongxue; Kennard, Mark J.

2018-04-01

River channel drying caused by intermittent stream flow is a widely-recognized factor shaping stream ecosystems. There is a strong need to quantify the distribution of intermittent streams across catchments to inform management. However, observational gauge networks provide only point estimates of streamflow variation. Increasingly, this limitation is being overcome through the use of spatially contiguous estimates of the terrestrial water-balance, which can also assist in estimating runoff and streamflow at large-spatial scales. Here we proposed an approach to quantifying spatial and temporal variation in monthly flow intermittency throughout river networks in eastern Australia. We aggregated gridded (5 × 5 km) monthly water-balance data with a hierarchically nested catchment dataset to simulate catchment runoff accumulation throughout river networks from 1900 to 2016. We also predicted zero flow duration for the entire river network by developing a robust predictive model relating measured zero flow duration (% months) to environmental predictor variables (based on 43 stream gauges). We then combined these datasets by using the predicted zero flow duration from the regression model to determine appropriate 'zero' flow thresholds for the modelled discharge data, which varied spatially across the catchments examined. Finally, based on modelled discharge data and identified actual zero flow thresholds, we derived summary metrics describing flow intermittency across the catchment (mean flow duration and coefficient-of-variation in flow permanence from 1900 to 2016). We also classified the relative degree of flow intermittency annually to characterise temporal variation in flow intermittency. Results showed that the degree of flow intermittency varied substantially across streams in eastern Australia, ranging from perennial streams flowing permanently (11-12 months) to strongly intermittent streams flowing 4 months or less of year. Results also showed that the

Mobil Viral Pazarlama

OpenAIRE

Barutçu, Süleyman

2011-01-01

OBJECTIVE: Mobile Viral Marketing, with using mobile phones, is one of the most importantinnovations after Word of Mouth Marketing performed by face to face amongpeople and Viral Marketing performed in the İnternet. The main objective of thisstudy is to call marketing communicators’ and academicians’ attentions whowant to increase the recognition of companies’ products, services and brands tobecome a current issue in the marketplace using Mobile Viral Marketingapplications by reason of techno...

Randomized trial of intermittent or continuous amnioinfusion for variable decelerations.

Science.gov (United States)

Rinehart, B K; Terrone, D A; Barrow, J H; Isler, C M; Barrilleaux, P S; Roberts, W E

2000-10-01

To determine whether continuous or intermittent bolus amnioinfusion is more effective in relieving variable decelerations. Patients with repetitive variable decelerations were randomized to an intermittent bolus or continuous amnioinfusion. The intermittent bolus infusion group received boluses of 500 mL of normal saline, each over 30 minutes, with boluses repeated if variable decelerations recurred. The continuous infusion group received a bolus infusion of 500 mL of normal saline over 30 minutes and then 3 mL per minute until delivery occurred. The ability of the amnioinfusion to abolish variable decelerations was analyzed, as were maternal demographic and pregnancy outcome variables. Power analysis indicated that 64 patients would be required. Thirty-five patients were randomized to intermittent infusion and 30 to continuous infusion. There were no differences between groups in terms of maternal demographics, gestational age, delivery mode, neonatal outcome, median time to resolution of variable decelerations, or the number of times variable decelerations recurred. The median volume infused in the intermittent infusion group (500 mL) was significantly less than that in the continuous infusion group (905 mL, P =.003). Intermittent bolus amnioinfusion is as effective as continuous infusion in relieving variable decelerations in labor. Further investigation is necessary to determine whether either of these techniques is associated with increased occurrence of rare complications such as cord prolapse or uterine rupture.

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.

Accelerated magnetic resonance diffusion tensor imaging of the median nerve using simultaneous multi-slice echo planar imaging with blipped CAIPIRINHA

Energy Technology Data Exchange (ETDEWEB)

Filli, Lukas; Kenkel, David; Boss, Andreas; Manoliu, Andrei; Andreisek, Gustav; Runge, Val M.; Guggenberger, Roman [University Hospital of Zurich, University of Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland); Piccirelli, Marco [University Hospital of Zurich, Department of Neuroradiology, Zurich (Switzerland); Bhat, Himanshu [Siemens Medical Solutions USA Inc, Charlestown, MA (United States)

2016-06-15

To investigate the feasibility of MR diffusion tensor imaging (DTI) of the median nerve using simultaneous multi-slice echo planar imaging (EPI) with blipped CAIPIRINHA. After federal ethics board approval, MR imaging of the median nerves of eight healthy volunteers (mean age, 29.4 years; range, 25-32) was performed at 3 T using a 16-channel hand/wrist coil. An EPI sequence (b-value, 1,000 s/mm{sup 2}; 20 gradient directions) was acquired without acceleration as well as with twofold and threefold slice acceleration. Fractional anisotropy (FA), mean diffusivity (MD) and quality of nerve tractography (number of tracks, average track length, track homogeneity, anatomical accuracy) were compared between the acquisitions using multivariate ANOVA and the Kruskal-Wallis test. Acquisition time was 6:08 min for standard DTI, 3:38 min for twofold and 2:31 min for threefold acceleration. No differences were found regarding FA (standard DTI: 0.620 ± 0.058; twofold acceleration: 0.642 ± 0.058; threefold acceleration: 0.644 ± 0.061; p ≥ 0.217) and MD (standard DTI: 1.076 ± 0.080 mm{sup 2}/s; twofold acceleration: 1.016 ± 0.123 mm{sup 2}/s; threefold acceleration: 0.979 ± 0.153 mm{sup 2}/s; p ≥ 0.074). Twofold acceleration yielded similar tractography quality compared to standard DTI (p > 0.05). With threefold acceleration, however, average track length and track homogeneity decreased (p = 0.004-0.021). Accelerated DTI of the median nerve is feasible. Twofold acceleration yields similar results to standard DTI. (orig.)

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...

Understanding Image Virality

Science.gov (United States)

2015-06-07

Example non-viral images. Figure 1: Top: Images with high viral scores in our dataset depict internet “celebrity” memes ex. “Grumpy Cat”; Bottom: Images...of images that is most similar to ours is the concurrently introduced viral meme generator of Wang et al., that combines NLP and Computer Vision (low...doing any of our tasks. The test included questions about widely spread Reddit memes and jargon so that anyone familiar with Reddit can easily get a high

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.

Intermittent synchronization in a network of bursting neurons

Science.gov (United States)

Park, Choongseok; Rubchinsky, Leonid L.

2011-09-01

Synchronized oscillations in networks of inhibitory and excitatory coupled bursting neurons are common in a variety of neural systems from central pattern generators to human brain circuits. One example of the latter is the subcortical network of the basal ganglia, formed by excitatory and inhibitory bursters of the subthalamic nucleus and globus pallidus, involved in motor control and affected in Parkinson's disease. Recent experiments have demonstrated the intermittent nature of the phase-locking of neural activity in this network. Here, we explore one potential mechanism to explain the intermittent phase-locking in a network. We simplify the network to obtain a model of two inhibitory coupled elements and explore its dynamics. We used geometric analysis and singular perturbation methods for dynamical systems to reduce the full model to a simpler set of equations. Mathematical analysis was completed using three slow variables with two different time scales. Intermittently, synchronous oscillations are generated by overlapped spiking which crucially depends on the geometry of the slow phase plane and the interplay between slow variables as well as the strength of synapses. Two slow variables are responsible for the generation of activity patterns with overlapped spiking, and the other slower variable enhances the robustness of an irregular and intermittent activity pattern. While the analyzed network and the explored mechanism of intermittent synchrony appear to be quite generic, the results of this analysis can be used to trace particular values of biophysical parameters (synaptic strength and parameters of calcium dynamics), which are known to be impacted in Parkinson's disease.

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.

Generation of intermittent gravitocapillary waves via parametric forcing

Science.gov (United States)

Castillo, Gustavo; Falcón, Claudio

2018-04-01

We report on the generation of an intermittent wave field driven by a horizontally moving wave maker interacting with Faraday waves. The spectrum of the local gravitocapillary surface wave fluctuations displays a power law in frequency for a wide range of forcing parameters. We compute the probability density function of the local surface height increments, which show that they change strongly across time scales. The structure functions of these increments are shown to display power laws as a function of the time lag, with exponents that are nonlinear functions of the order of the structure function. We argue that the origin of this scale-invariant intermittent spectrum is the Faraday wave pattern breakup due to its advection by the propagating gravity waves. Finally, some interpretations are proposed to explain the appearance of this intermittent spectrum.

Intermittency in e+e- and lepton-hadron collisions

International Nuclear Information System (INIS)

Sugano, K.

1990-01-01

The intermittency data in e + e - and lepton-hadron collisions are reviewed. The power-law behavior of the moments has been established by various e + e - experiments and a μp experiment. The intermittency in the two-dimensional space of rapidity and azimuthal angle is much stronger than in the rapidity space only. The neutrino-nucleus data indicate significant effects from nuclear reinteractions. The LUND parton shower model fits the data better than the matrix element model without special retuning. The relations among the moments of different orders are in good agreement with the predictions by the negative binomial and pure birth distributions. The origin of the intermittency in e + e - and μp collisions is consistent with the self-similar cascade mechanism of jet formation. 11 refs., 7 figs

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.

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.

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...

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).

Isolated intermittent vertigo: A presenting feature of persistent trigeminal artery

Directory of Open Access Journals (Sweden)

Rajsrinivas Parthasarathy

2016-01-01

Full Text Available Embryonic carotid – basilar anastomosis when persistent in adult life can present with a variety of neurological symptoms. We present a patient with isolated intermittent vertigo attributable to the embryonic anastomosis and describe the different types of persistent trigeminal artery. A 76-year-old Caucasian man presented with isolated intermittent vertigo and symptoms suggestive of anterior and posterior circulation strokes. Impaired vasomotor reactivity was demonstrated on insonation of the anterior and posterior cerebral arteries in this patient with a persistent left trigeminal artery and 75% stenosis of the left internal carotid artery (ICA. The symptom of intermittent vertigo resolved with carotid endarterectomy. Decreased flow across the stenotic segment of the ICA which subserved the posterior circulation resulted in basilar insufficiency. Hypoperfusion to the flocculonodular lobe supplied by the anterior inferior cerebellar artery is a likely cause for the intermittent vertigo.

Radial evolution of the intermittency of density fluctuations in the fast solar wind

International Nuclear Information System (INIS)

Bruno, R.; D'Amicis, R.; Telloni, D.; Primavera, L.; Sorriso-Valvo, L.; Carbone, V.; Malara, F.; Veltri, P.; Pietropaolo, E.

2014-01-01

We study the radial evolution of the intermittency of density fluctuations in the fast solar wind. The study is performed by analyzing the plasma density measurements provided by Helios 2 in the inner heliosphere between 0.3 and 0.9 AU. The analysis is carried out by means of a complete set of diagnostic tools, including the flatness factor at different timescales to estimate intermittency, the Kolmogorov-Smirnov test to estimate the degree of intermittency, and the Fourier transform to estimate the power spectral densities of these fluctuations. Density fluctuations within the fast wind are rather intermittent and their level of intermittency, together with the amplitude of intermittent events, decreases with the distance from the Sun, at odds with the intermittency of both magnetic field and all other plasma parameters. Furthermore, the intermittent events are strongly correlated, exhibiting temporal clustering. This indicates that the mechanism underlying their generation departs from a time-varying Poisson process. A remarkable, qualitative similarity with the behavior of plasma density fluctuations obtained from a numerical study of the nonlinear evolution of parametric instability in the solar wind supports the idea that this mechanism has an important role in governing density fluctuations in the inner heliosphere.

Sensitivity of intermittent streams to climate variations in the United States

Science.gov (United States)

Eng, K.

2015-12-01

There is growing interest in the effects of climate change on streamflows because of the potential negative effects on aquatic biota and water supplies. Previous studies of climate controls on flows have primarily focused on perennial streams, and few studies have examined the effect of climate variability on intermittent streams. Our objectives in this study were to (1) identify regions showing similar patterns of intermittency, and (2) evaluate the sensitivity of intermittent streams to historical variability in climate in the United States. This study was carried out at 265 intermittent streams by evaluating: (1) correlations among time series of flow metrics (number of zero-flow events, the average of the central 50% and largest 10% of flows) with precipitation (magnitudes, durations and intensity) and temperature, and (2) decadal changes in the seasonality and long-term trends of these flow metrics. Results identified five distinct seasonal patterns of flow intermittency: fall, fall-to-winter, non-seasonal, summer, and summer-to-winter intermittent streams. In addition, strong associations between the low-flow metrics and historical climate variability were found. However, the lack of trends in historical variations in precipitation results in no significant seasonal shifts or decade-to-decade trends in the low-flow metrics over the period of record (1950 to 2013).

Bile acids for viral hepatitis

DEFF Research Database (Denmark)

Chen, Weikeng; Liu, J; Gluud, C

2003-01-01

The viral hepatitides are common causes of liver diseases globally. Trials have assessed bile acids for patients with viral hepatitis, but no consensus was reached regarding their usefulness.......The viral hepatitides are common causes of liver diseases globally. Trials have assessed bile acids for patients with viral hepatitis, but no consensus was reached regarding their usefulness....

Viral hemorrhagic septicemia

Science.gov (United States)

Batts, William N.; Winton, James R.

2012-01-01

Viral hemorrhagic septicemia (VHS) is one of the most important viral diseases of finfish worldwide. In the past, VHS was thought to affect mainly rainbow trout Oncorhynchus mykiss reared at freshwater facilities in Western Europe where it was known by various names including Egtved disease and infectious kidney swelling and liver degeneration (Wolf 1988). Today, VHS is known as an important source of mortality for cultured and wild fish in freshwater and marine environments in several regions of the northern hemisphere (Dixon 1999; Gagné et al. 2007; Kim and Faisal 2011; Lumsden et al. 2007; Marty et al. 1998, 2003; Meyers and Winton 1995; Skall et al. 2005b; Smail 1999; Takano et al. 2001). Viral hemorrhagic septicemia is caused by the fish rhabdovirus, viral hemorrhagic septicemia virus (VHSV), a member of the genus Novirhabdovirus of the family Rhabdoviridae

Intermittent hypoxic episodes in preterm infants: do they matter?

Science.gov (United States)

Martin, Richard J; Wang, Katherine; Köroğlu, Ozge; Di Fiore, Juliann; Kc, Prabha

2011-01-01

Intermittent hypoxic episodes are typically a consequence of immature respiratory control and remain a troublesome challenge for the neonatologist. Furthermore, their frequency and magnitude are underestimated by clinically employed pulse oximeter settings. In extremely low birth weight infants the incidence of intermittent hypoxia progressively increases over the first 4 weeks of postnatal life, with a subsequent plateau followed by a slow decline beginning at weeks 6-8. Such episodic hypoxia/reoxygenation has the potential to sustain a proinflammatory cascade with resultant multisystem morbidity. This morbidity includes retinopathy of prematurity and impaired growth, as well as possible longer-term cardiorespiratory instability and poor neurodevelopmental outcome. Therapeutic approaches for intermittent hypoxic episodes comprise determination of optimal baseline saturation and careful titration of supplemental inspired oxygen, as well as xanthine therapy to prevent apnea of prematurity. In conclusion, characterization of the pathophysiologic basis for such intermittent hypoxic episodes and their consequences during early life is necessary to provide an evidence-based approach to their management. Copyright © 2011 S. Karger AG, Basel.

Multiparticle correlations and intermittency in high energy collisions

CERN Document Server

Bozek, P

1992-01-01

In this work the analysis of the intermittency signal observed in high energy experi- ments is done using multiparticle distributions and correlation functions. The effect of the dimensional projection of the multiparticle distributions on one or two-dimensional subspace is discussed. The structure of the multiparticle cumulants is analyzed for the DELPHI e + e~ annihilation data. The language of the self-similar distribution func- tions, which is used in this work, is shown to be largely equivalent to the well known a-model. In the case of the ultrarelativistic nuclear collisions, where the Monte-Carlo simulations fail to reproduce the data, we argue that the observed intermittency pattern is a signal of some nonlinear effect beyond the simple superposition of nucleon-nucleon collisions. The model of spatiotemporal intermittency is discussed in details and is shown to reproduce qualitatively the dependence of t...

ViralORFeome: an integrated database to generate a versatile collection of viral ORFs.

Science.gov (United States)

Pellet, J; Tafforeau, L; Lucas-Hourani, M; Navratil, V; Meyniel, L; Achaz, G; Guironnet-Paquet, A; Aublin-Gex, A; Caignard, G; Cassonnet, P; Chaboud, A; Chantier, T; Deloire, A; Demeret, C; Le Breton, M; Neveu, G; Jacotot, L; Vaglio, P; Delmotte, S; Gautier, C; Combet, C; Deleage, G; Favre, M; Tangy, F; Jacob, Y; Andre, P; Lotteau, V; Rabourdin-Combe, C; Vidalain, P O

2010-01-01

Large collections of protein-encoding open reading frames (ORFs) established in a versatile recombination-based cloning system have been instrumental to study protein functions in high-throughput assays. Such 'ORFeome' resources have been developed for several organisms but in virology, plasmid collections covering a significant fraction of the virosphere are still needed. In this perspective, we present ViralORFeome 1.0 (http://www.viralorfeome.com), an open-access database and management system that provides an integrated set of bioinformatic tools to clone viral ORFs in the Gateway(R) system. ViralORFeome provides a convenient interface to navigate through virus genome sequences, to design ORF-specific cloning primers, to validate the sequence of generated constructs and to browse established collections of virus ORFs. Most importantly, ViralORFeome has been designed to manage all possible variants or mutants of a given ORF so that the cloning procedure can be applied to any emerging virus strain. A subset of plasmid constructs generated with ViralORFeome platform has been tested with success for heterologous protein expression in different expression systems at proteome scale. ViralORFeome should provide our community with a framework to establish a large collection of virus ORF clones, an instrumental resource to determine functions, activities and binding partners of viral proteins.

UGGT1 enhances enterovirus 71 pathogenicity by promoting viral RNA synthesis and viral replication.

Directory of Open Access Journals (Sweden)

Peng-Nien Huang

2017-05-01

Full Text Available Positive-strand RNA virus infections can induce the stress-related unfolded protein response (UPR in host cells. This study found that enterovirus A71 (EVA71 utilizes host UDP-glucose glycoprotein glucosyltransferase 1 (UGGT1, a key endoplasmic reticulum protein (ER involved in UPR, to enhance viral replication and virulence. EVA71 forms replication complexes (RCs on cellular membranes that contain a mix of host and viral proteins to facilitate viral replication, but the components and processes involved in the assembly and function of RCs are not fully understood. Using EVA71 as a model, this study found that host UGGT1 and viral 3D polymerase co-precipitate along with other factors on membranous replication complexes to enhance viral replication. Increased UGGT1 levels elevated viral growth rates, while viral pathogenicity was observed to be lower in heterozygous knockout mice (Uggt1 +/- mice. These findings provide important insight on the role of UPR and host UGGT1 in regulating RNA virus replication and pathogenicity.

[Effect of intermittent hypoxia of sleep apnea on embryonic rat cortical neurons in vitro].

Science.gov (United States)

Zhang, Chanjuan; Li, Yanzhong; Wang, Yan

2015-05-01

To investigate the effects of different pattens of intermittent hypoxia on the activity and apoptosis of primary cultured rat embryonic cortical neurons, and to evaluate the role of intermittent hypoxia in the mechanism of obstructive sleep syndrom induced cognitive function loss. The embryonic cerebral cortical neurons were cultured in vitro and were identified by immunofluorescence. Cultured neurons were randomly divided into intermittent hypoxia group, intermittent normal oxygen group, persistent hypoxia group and the control group, and intermittent hypoxia group was divided into five subgroups according to different frequency and time-bound. Neurons were exposed in different modes of hypoxia. MTT colorimetry was used to detect the viability of the neurons, and DAPI colorated measurement was used to calculate the percentages of neuron apoptosis. There were significantly different effects between all subgroups of intermittent hypoxia and the continued hypoxia group on neuronal activity and apoptosis (P Intermittent hypoxia groups with different frequency and time had no difference in neuronal activity and apoptosis (P > 0.05). The effect of intermittent hypoxia was more serious than that of continued hypoxia on neuronal activity and apoptosis; The impact of intermittent hypoxia on neuronal activity and apoptosis may be an important factor in obstructive sleep apnea related cognitive impairment.

Viral Marketing

OpenAIRE

Sorina Raula Gîrboveanu; Silvia Puiu

2008-01-01

With consumers showing increasing resistance to traditional forms of advertising such as TV or newspaper ads, marketers have turned to alternate strategies, including viral marketing. Viral marketing exploits existing social networks by encouraging customers to share product information with their friends.In our study we are able to directly observe the effectiveness of person to person word of mouth advertising for hundreds of thousands of products for the first time

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...

On intermittent flow characteristics of gas–liquid two-phase flow

Energy Technology Data Exchange (ETDEWEB)

Thaker, Jignesh; Banerjee, Jyotirmay, E-mail: jbaner@gmail.com

2016-12-15

Highlights: • Unified correlations for intermittent flow characteristics are developed. • Influence of inflow conditions on intermittent flow characteristics is analysed. • Developed correlations can be used for effective design of piping components. - Abstract: Flow visualisation experiments are reported for intermittent regime of gas–liquid two-phase flow. Intermittent flow characteristics, which include plug/slug frequency, liquid plug/slug velocity, liquid plug/slug length, and plug/slug bubble length are determined by image processing of flow patterns captured at a rate of 1600 frames per second (FPS). Flow characteristics are established as a function of inlet superficial velocity of both the phases (in terms of Re{sub SL} and Re{sub SG}). The experimental results are first validated with the existing correlations for slug flow available in literature. It is observed that the correlations proposed in literature for slug flow do not accurately predict the flow characteristics in the plug flow regime. The differences are clearly highlighted in this paper. Based on the measured database for both plug and slug flow regime, modified correlations for the intermittent flow regime are proposed. The correlations reported in the present paper, which also include plug flow characteristics will aid immensely to the effective design and optimization of operating conditions for safer operation of two-phase flow piping systems.

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.

Clinical feasibility of simultaneous multi-slice imaging with blipped-CAIPI for diffusion-weighted imaging and diffusion-tensor imaging of the brain.

Science.gov (United States)

Yokota, Hajime; Sakai, Koji; Tazoe, Jun; Goto, Mariko; Imai, Hiroshi; Teramukai, Satoshi; Yamada, Kei

2017-12-01

Background Simultaneous multi-slice (SMS) imaging is starting to be used in clinical situation, although evidence of clinical feasibility is scanty. Purpose To prospectively assess the clinical feasibility of SMS diffusion-weighted imaging (DWI) and diffusion-tensor imaging (DTI) with blipped-controlled aliasing in parallel imaging for brain lesions. Material and Methods The institutional review board approved this study. This study included 156 hyperintense lesions on DWI from 32 patients. A slice acceleration factor of 2 was applied for SMS scans, which allowed shortening of the scan time by 41.3%. The signal-to-noise ratio (SNR) was calculated for brain tissue of a selected slice. The contrast-to-noise ratio (CNR), apparent diffusion coefficient (ADC), and fractional anisotropy (FA) were calculated in 36 hyperintense lesions with a diameter of three pixels or more. Visual assessment was performed for all 156 lesions. Tractography of the corticospinal tract of 29 patients was evaluated. The number of tracts and averaged tract length were used for quantitative analysis, and visual assessment was evaluated by grading. Results The SMS scan showed no bias and acceptable 95% limits of agreement compared to conventional scans in SNR, CNR, and ADC on Bland-Altman analyses. Only FA of the lesions was higher in the SMS scan by 9% ( P = 0.016), whereas FA of the surrounding tissues was similar. Quantitative analysis of tractography showed similar values. Visual assessment of DWI hyperintense lesions and tractography also resulted in comparable evaluation. Conclusion SMS imaging was clinically feasible for imaging quality and quantitative values compared with conventional DWI and DTI.

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…

Intermittent Hypoxia Alters Gene Expression in Peripheral Blood Mononuclear Cells of Healthy Volunteers.

Science.gov (United States)

Polotsky, Vsevolod Y; Bevans-Fonti, Shannon; Grigoryev, Dmitry N; Punjabi, Naresh M

2015-01-01

Obstructive sleep apnea is associated with high cardiovascular morbidity and mortality. Intermittent hypoxia of obstructive sleep apnea is implicated in the development and progression of insulin resistance and atherosclerosis, which have been attributed to systemic inflammation. Intermittent hypoxia leads to pro-inflammatory gene up-regulation in cell culture, but the effects of intermittent hypoxia on gene expression in humans have not been elucidated. A cross-over study was performed exposing eight healthy men to intermittent hypoxia or control conditions for five hours with peripheral blood mononuclear cell isolation before and after exposures. Total RNA was isolated followed by gene microarrays and confirmatory real time reverse transcriptase PCR. Intermittent hypoxia led to greater than two fold up-regulation of the pro-inflammatory gene toll receptor 2 (TLR2), which was not increased in the control exposure. We hypothesize that up-regulation of TLR2 by intermittent hypoxia may lead to systemic inflammation, insulin resistance and atherosclerosis in patients with obstructive sleep apnea.

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.

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.

Intermittent hypercapnic hypoxia during sleep does not induce ventilatory long-term facilitation in healthy males.

Science.gov (United States)

Deacon, Naomi L; McEvoy, R Doug; Stadler, Daniel L; Catcheside, Peter G

2017-09-01

Intermittent hypoxia-induced ventilatory neuroplasticity is likely important in obstructive sleep apnea pathophysiology. Although concomitant CO 2 levels and arousal state critically influence neuroplastic effects of intermittent hypoxia, no studies have investigated intermittent hypercapnic hypoxia effects during sleep in humans. Thus the purpose of this study was to investigate if intermittent hypercapnic hypoxia during sleep induces neuroplasticity (ventilatory long-term facilitation and increased chemoreflex responsiveness) in humans. Twelve healthy males were exposed to intermittent hypercapnic hypoxia (24 × 30 s episodes of 3% CO 2 and 3.0 ± 0.2% O 2 ) and intermittent medical air during sleep after 2 wk washout period in a randomized crossover study design. Minute ventilation, end-tidal CO 2 , O 2 saturation, breath timing, upper airway resistance, and genioglossal and diaphragm electromyograms were examined during 10 min of stable stage 2 sleep preceding gas exposure, during gas and intervening room air periods, and throughout 1 h of room air recovery. There were no significant differences between conditions across time to indicate long-term facilitation of ventilation, genioglossal or diaphragm electromyogram activity, and no change in ventilatory response from the first to last gas exposure to suggest any change in chemoreflex responsiveness. These findings contrast with previous intermittent hypoxia studies without intermittent hypercapnia and suggest that the more relevant gas disturbance stimulus of concomitant intermittent hypercapnia frequently occurring in sleep apnea influences acute neuroplastic effects of intermittent hypoxia. These findings highlight the need for further studies of intermittent hypercapnic hypoxia during sleep to clarify the role of ventilatory neuroplasticity in the pathophysiology of sleep apnea. NEW & NOTEWORTHY Both arousal state and concomitant CO 2 levels are known modulators of the effects of intermittent hypoxia on

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)

Value of Sharing: Viral Advertisement

OpenAIRE

Duygu Aydın; Aşina Gülerarslan; Süleyman Karaçor; Tarık Doğan

2013-01-01

Sharing motivations of viral advertisements by consumers and the impacts of these advertisements on the perceptions for brand will be questioned in this study. Three fundamental questions are answered in the study. These are advertisement watching and sharing motivations of individuals, criteria of liking viral advertisement and the impact of individual attitudes for viral advertisement on brand perception respectively. This study will be carried out via a viral advertise...

Viral Marketing and Academic Institution

OpenAIRE

Koktová, Silvie

2010-01-01

This bachelor thesis examines modern and constantly developing kind of internet marketing -- the so called viral marketing. It deals with its origin, principle, process, advantages and disadvantages, types of viral marketing and presumptions of creating successful viral campaign. The aim of the theoretical part is especially the understanding of viral marketing as one of the effective instruments of contemporary marketing. In this theoretical part the thesis also elaborates a marketing school...

Randomized double-blind placebo-controlled crossover study of caffeine in patients with intermittent claudication

DEFF Research Database (Denmark)

Momsen, A H; Jensen, M B; Norager, C B

2010-01-01

Intermittent claudication is a disabling symptom of peripheral arterial disease for which few medical treatments are available. This study investigated the effect of caffeine on physical capacity in patients with intermittent claudication.......Intermittent claudication is a disabling symptom of peripheral arterial disease for which few medical treatments are available. This study investigated the effect of caffeine on physical capacity in patients with intermittent claudication....

Critical behavior of the Lyapunov exponent in type-III intermittency

Energy Technology Data Exchange (ETDEWEB)

Alvarez-Llamoza, O. [Departamento de Fisica, FACYT, Universidad de Carabobo, Valencia (Venezuela); Centro de Fisica Fundamental, Grupo de Caos y Sistemas Complejos, Universidad de Los Andes, Merida 5251, Merida (Venezuela)], E-mail: llamoza@ula.ve; Cosenza, M.G. [Centro de Fisica Fundamental, Grupo de Caos y Sistemas Complejos, Universidad de Los Andes, Merida 5251, Merida (Venezuela); Ponce, G.A. [Departamento de Fisica, Universidad Nacional Autonoma de Honduras (Honduras); Departamento de Ciencias Naturales, Universidad Pedagogica Nacional Francisco Morazan, Tegucigalpa (Honduras)

2008-04-15

The critical behavior of the Lyapunov exponent near the transition to robust chaos via type-III intermittency is determined for a family of one-dimensional singular maps. Critical boundaries separating the region of robust chaos from the region where stable fixed points exist are calculated on the parameter space of the system. A critical exponent {beta} expressing the scaling of the Lyapunov exponent is calculated along the critical curve corresponding to the type-III intermittent transition to chaos. It is found that {beta} varies on the interval 0 {<=} {beta} < 1/2 as a function of the order of the singularity of the map. This contrasts with earlier predictions for the scaling behavior of the Lyapunov exponent in type-III intermittency. The variation of the critical exponent {beta} implies a continuous change in the nature of the transition to chaos via type-III intermittency, from a second-order, continuous transition to a first-order, discontinuous transition.

Critical behavior of the Lyapunov exponent in type-III intermittency

International Nuclear Information System (INIS)

Alvarez-Llamoza, O.; Cosenza, M.G.; Ponce, G.A.

2008-01-01

The critical behavior of the Lyapunov exponent near the transition to robust chaos via type-III intermittency is determined for a family of one-dimensional singular maps. Critical boundaries separating the region of robust chaos from the region where stable fixed points exist are calculated on the parameter space of the system. A critical exponent β expressing the scaling of the Lyapunov exponent is calculated along the critical curve corresponding to the type-III intermittent transition to chaos. It is found that β varies on the interval 0 ≤ β < 1/2 as a function of the order of the singularity of the map. This contrasts with earlier predictions for the scaling behavior of the Lyapunov exponent in type-III intermittency. The variation of the critical exponent β implies a continuous change in the nature of the transition to chaos via type-III intermittency, from a second-order, continuous transition to a first-order, discontinuous transition

Intermittently chaotic oscillations for a differential-delay equation with Gaussian nonlinearity

Science.gov (United States)

Hamilton, Ian

1992-01-01

For a differential-delay equation the time dependence of the variable is a function of the variable at a previous time. We consider a differential-delay equation with Gaussian nonlinearity that displays intermittent chaos. Although not the first example of a differential-delay equation that displays such behavior, for this example the intermittency is classified as type III, and the origin of the intermittent chaos may be qualitatively understood from the limiting forms of the equation for large and small variable magnitudes.

Intermittency and multifractional Brownian character of geomagnetic time series

Directory of Open Access Journals (Sweden)

G. Consolini

2013-07-01

Full Text Available The Earth's magnetosphere exhibits a complex behavior in response to the solar wind conditions. This behavior, which is described in terms of mutifractional Brownian motions, could be the consequence of the occurrence of dynamical phase transitions. On the other hand, it has been shown that the dynamics of the geomagnetic signals is also characterized by intermittency at the smallest temporal scales. Here, we focus on the existence of a possible relationship in the geomagnetic time series between the multifractional Brownian motion character and the occurrence of intermittency. In detail, we investigate the multifractional nature of two long time series of the horizontal intensity of the Earth's magnetic field as measured at L'Aquila Geomagnetic Observatory during two years (2001 and 2008, which correspond to different conditions of solar activity. We propose a possible double origin of the intermittent character of the small-scale magnetic field fluctuations, which is related to both the multifractional nature of the geomagnetic field and the intermittent character of the disturbance level. Our results suggest a more complex nature of the geomagnetic response to solar wind changes than previously thought.

Physiologic basis for intermittent hypoxic episodes in preterm infants.

Science.gov (United States)

Martin, R J; Di Fiore, J M; Macfarlane, P M; Wilson, C G

2012-01-01

Intermittent hypoxic episodes are typically a consequence of immature respiratory control and remain a troublesome challenge for the neonatologist. Furthermore, their frequency and magnitude are commonly underestimated by clinically employed pulse oximeter settings. In extremely low birth weight infants the incidence of intermittent hypoxia [IH] progressively increases over the first 4 weeks of postnatal life, with a subsequent plateau followed by a slow decline beginning at weeks six to eight. Over this period of unstable respiratory control, increased oxygen-sensitive peripheral chemoreceptor activity has been associated with a higher incidence of apnea of prematurity. In contrast, infants with bronchopulmonary dysplasia [chronic neonatal lung disease] exhibit decreased peripheral chemosensitivity, although the effect on respiratory stability in this population is unclear. Such episodic hypoxia/reoxygenation in early life has the potential to sustain a proinflammatory cascade with resultant multisystem, including respiratory, morbidity. Therapeutic approaches for intermittent hypoxic episodes comprise careful titration of baseline or supplemental inspired oxygen as well as xanthine therapy to prevent apnea of prematurity. Characterization of the pathophysiologic basis for such intermittent hypoxic episodes and their consequences during early life is necessary to provide an evidence-based approach to their management.

[Emergent viral infections

NARCIS (Netherlands)

Galama, J.M.D.

2001-01-01

The emergence and re-emergence of viral infections is an ongoing process. Large-scale vaccination programmes led to the eradication or control of some viral infections in the last century, but new viruses are always emerging. Increased travel is leading to a rise in the importation of exotic

Intermittent Anisotropic Turbulence Detected by THEMIS in the Magnetosheath

Science.gov (United States)

Macek, W. M.; Wawrzaszek, A.; Kucharuk, B.; Sibeck, D. G.

2017-12-01

Following our previous study of Time History of Events and Macroscale Interactions during Substorms (THEMIS) data, we consider intermittent turbulence in the magnetosheath depending on various conditions of the magnetized plasma behind the Earth’s bow shock and now also near the magnetopause. Namely, we look at the fluctuations of the components of the Elsässer variables in the plane perpendicular to the scale-dependent background magnetic fields and along the local average ambient magnetic fields. We have shown that Alfvén fluctuations often exhibit strong anisotropic non-gyrotropic turbulent intermittent behavior resulting in substantial deviations of the probability density functions from a normal Gaussian distribution with a large kurtosis. In particular, for very high Alfvénic Mach numbers and high plasma beta, we have clear anisotropy with non-Gaussian statistics in the transverse directions. However, along the magnetic field, the kurtosis is small and the plasma is close to equilibrium. On the other hand, intermittency becomes weaker for moderate Alfvén Mach numbers and lower values of the plasma parameter beta. It also seems that the degree of intermittency of turbulence for the outgoing fluctuations propagating relative to the ambient magnetic field is usually similar as for the ingoing fluctuations, which is in agreement with approximate equipartition of energy between these oppositely propagating Alfvén waves. We believe that the different characteristics of this intermittent anisotropic turbulent behavior in various regions of space and astrophysical plasmas can help identify nonlinear structures responsible for deviations of the plasma from equilibrium.

Wave-Number Spectra and Intermittency in the Terrestrial Foreshock Region

International Nuclear Information System (INIS)

Narita, Y.; Glassmeier, K.-H.; Treumann, R. A.

2006-01-01

Wave-number spectra of magnetic field fluctuations are directly determined in the terrestrial foreshock region (upstream of a quasiparallel collisionless shock wave) using four-point Cluster spacecraft measurements. The spectral curve is characterized by three ranges reminiscent of turbulence: energy injection, inertial, and dissipation range. The spectral index for the inertial range spectrum is close to Kolmogorov's slope, -5/3. On the other hand, the fluctuations are highly anisotropic and intermittent perpendicular to the mean magnetic field direction. These results suggest that the foreshock is in a weakly turbulent and intermittent state in which parallel propagating Alfven waves interact with one another, resulting in the phase coherence or the intermittency

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...

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...

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...

New advances on chaotic intermittency and its applications

CERN Document Server

Elaskar, Sergio

2017-01-01

One of the most important routes to chaos is the chaotic intermittency. However, there are many cases that do not agree with the classical theoretical predictions. In this book, an extended theory for intermittency in one-dimensional maps is presented. A new general methodology to evaluate the reinjection probability density function (RPD) is developed in Chapters 5 to 8. The key of this formulation is the introduction of a new function, called M(x), which is used to calculate the RPD function. The function M(x) depends on two integrals. This characteristic reduces the influence on the statistical fluctuations in the data series. Also, the function M(x) is easy to evaluate from the data series, even for a small number of numerical or experimental data. As a result, a more general form for the RPD is found; where the classical theory based on uniform reinjection is recovered as a particular case. The characteristic exponent traditionally used to characterize the intermittency type, is now a function depending ...

Multiparticle correlations and intermittency in high energy collisions

International Nuclear Information System (INIS)

Bozek, P.

1992-01-01

The analysis of the intermittency signal observed in high energy experiments is presented using multiparticle distributions and correlation functions. The effect of the dimensional projection of the multiparticle distributions on one or two-dimensional subspace is discussed. The structure of the multiparticle cumulants is analyzed for the DELPHI e + e - annihilation data. The model of spatiotemporal intermittency is discussed in details and is shown to reproduce qualitatively the dependence of the intermittency strength on the target and projectile nuclei. A 1-dimensional (1D) cellular-automaton and a 1D forest-fire model is studied. On the example of the noncritical 1D Ising model the difficulties of the scaled factorial moment (SFM) method in extracting genuine scaling behaviour is illustrated. All these studies could serve as tools to test the sensibility of the SFM method as used in the analysis of the high energy production. (K.A.) 122 refs.; 38 figs.; 3 tabs

Multiparticle correlations and intermittency in high energy collisions

International Nuclear Information System (INIS)

Bozek, P.

1992-01-01

An analysis of the intermittency signal observed in high energy experiments is presented using multiparticle distributions and correlation functions. The effect of the dimensional projection of the multiparticle distributions on one or two-dimensional subspace is discussed. The structure of the multiparticle cumulants is analyzed for the DELPHI e + e - annihilation data. The model of spatiotemporal intermittency is discussed in details and is shown to reproduce qualitatively the dependence of the intermittency strength on the target and projectile nuclei. A 1-dimensional (lD) cellular-automaton (CA) and a lD forest-fire model is studied. On the example of the noncritical lD Ising model the difficulties of the scaled factorial moment (SFM) method in extracting genuine scaling behaviour are illustrated. The problem of the finite-size effect in connection to the dimensional projection can be easily exemplified in the case of the 2D critical system with conformal symmetry. (R.P.) 122 refs., 38 figs., 3 tabs

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...

Intermittency in Hall-magnetohydrodynamics with a strong guide field

International Nuclear Information System (INIS)

Rodriguez Imazio, P.; Martin, L. N.; Dmitruk, P.; Mininni, P. D.

2013-01-01

We present a detailed study of intermittency in the velocity and magnetic field fluctuations of compressible Hall-magnetohydrodynamic turbulence with an external guide field. To solve the equations numerically, a reduced model valid when a strong guide field is present is used. Different values for the ion skin depth are considered in the simulations. The resulting data are analyzed computing field increments in several directions perpendicular to the guide field, and building structure functions and probability density functions. In the magnetohydrodynamic limit, we recover the usual results with the magnetic field being more intermittent than the velocity field. In the presence of the Hall effect, field fluctuations at scales smaller than the ion skin depth show a substantial decrease in the level of intermittency, with close to monofractal scaling

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.

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.

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.

Enhancing wastewater degradation and biogas production by intermittent operation of UASB reactors

International Nuclear Information System (INIS)

Nadais, Helena; Barbosa, Marta; Capela, Isabel; Arroja, Luis; Ramos, Christian G.; Grilo, Andre; Sousa, Silvia A.; Leitao, Jorge H.

2011-01-01

The present work establishes intermittent operation of UASB reactors as a novel form of enhancing the anaerobic degradation of complex wastewaters and its conversion to usable biogas. Results show that the average methane production rate is 25% higher with the intermittent operation than with the continuous mode, meaning that it could produce 25% more electricity or heat. The methanization efficiency obtained in intermittent UASB reactors is around 20% higher than in the continuous systems, confirming a higher biological degradation of the substrates. It has been suggested that intermittent operation causes a forced adaptation of the biomass towards the degradation of complex substrates and results from morphological analyses of the biomass developed in intermittent and continuous UASB reactors showed marked differences between them. In order to gain a deeper knowledge on how microbial populations are affected by these operational parameters, a strategy involving the amplification, cloning, and analysis of the nucleotide sequences of genes encoding the 16S ribosomal RNA was undertaken and is described in this work. This strategy allowed the identification of a total of 49 different sequences. Results from the molecular characterization of the microbial populations are consistent with the higher methanization efficiency of the intermittent mode of operation.

Intermittency inhibited by transport: An exactly solvable model

Science.gov (United States)

Zanette, Damián H.

1994-04-01

Transport is incorporated in a discrete-time stochastic model of a system undergoing autocatalytic reactions of the type A-->2A and A-->0, whose population field is known to exhibit spatiotemporal intermittency. The temporal evolution is exactly solved, and it is shown that if the transport process is strong enough, intermittency is inhibited. This inhibition is nonuniform, in the sense that, as transport is strengthened, low-order population moments are affected before the high-order ones. Numerical simulations are presented to support the analytical results.

Intermittent Hypoxic Episodes in Preterm Infants: Do They Matter?

OpenAIRE

Martin, Richard J.; Wang, Katherine; Köroğlu, Özge; Di Fiore, Juliann; Kc, Prabha

2011-01-01

Intermittent hypoxic episodes are typically a consequence of immature respiratory control and remain a troublesome challenge for the neonatologist. Furthermore, their frequency and magnitude are underestimated by clinically employed pulse oximeter settings. In extremely low birth weight infants the incidence of intermittent hypoxia progressively increases over the first 4 weeks of postnatal life, with a subsequent plateau followed by a slow decline beginning at weeks 6–8. Such episodic hypoxi...

Mobility and cloud: operating in intermittent, austere network conditions

OpenAIRE

Wee, Toon Joo; Ling, Yu Xian Eldine

2014-01-01

Approved for public release; distribution is unlimited Cloud computing is emerging as the mainstream platform for a range of on-demand applications, services, and infrastructure. Before the benefits of cloud computing are realized, several technology challenges must be addressed. Operating in intermittent and austere network conditions is one of such challenges, which navy ships face when communicating with land-based cloud computing environments. Given limited bandwidth and intermittent c...

Role of baseline HIV-1 DNA level in highly-experienced patients receiving raltegravir, etravirine and darunavir/ritonavir regimen (ANRS139 TRIO trial.

Directory of Open Access Journals (Sweden)

Charlotte Charpentier

Full Text Available OBJECTIVE: In the ANRS 139 TRIO trial, the use of 3 new active drugs (raltegravir, etravirine, and darunavir/ritonavir, resulted in a potent and sustained inhibition of viral replication in multidrug-resistant treatment-experienced patients. The aim of this virological sub-study of the ANRS 139 TRIO trial was to assess: (i the evolution of HIV-1 DNA over the first year; and (ii the association between baseline HIV-1 DNA and virological outcome. METHODS: Among the 103 HIV-1-infected patients included in the ANRS-139 TRIO trial, HIV-1 DNA specimens were available for 92, 84, 88, and 83 patients at Week (W0, W12, W24, and W48, respectively. Quantification of total HIV-1 DNA was performed by using the commercial kit "Generic HIV DNA Cell" (Biocentric, Bandol, France. RESULTS: Baseline median HIV-1 DNA of patients displaying virological success (n= 61, viral blip (n= 20, and virological failure (n = 11 were 2.34 log(10 copies/10(6 PBMC (IQR= 2.15-2.66, 2.42 (IQR = 2.12-2.48, and 2.68 (IQR= 2.46-2.83, respectively. Although not statistically significant, patients exhibiting virological success or viral blip had a tendency to display lower baseline HIV-1 DNA than patients experiencing virological failure (P = 0.06. Median decrease of HIV-1 DNA between baseline and W48 was -0.13 log(10 copies/10(6 PBMC (IQR = -0.34 to +0.10, mainly explained by the evolution from W0 to W4. No more changes were observed in the W4-W48 period. CONCLUSIONS: In highly-experienced multidrug-resistant patients, HIV-1 DNA slightly decreased during the first month and then remained stable during the first year of highly potent antiretroviral regimen. In this population, baseline HIV-1 DNA might help to better predict the virological response and to tailor clinical therapeutic management as more aggressive therapeutic choices in patients with higher baseline HIV-1 DNA.

The Effects of Intermittent Drinking Water Supply in Arraiján, Panama

OpenAIRE

Erickson, John Joseph

2016-01-01

Over three hundred million people throughout the world receive supply from piped drinking water distribution networks that operate intermittently. This dissertation evaluates the effects of intermittent supply on water quality, pipe damage and service reliability in four study zones (one continuous and three intermittent) in a peri-urban drinking water distribution network in Arraiján, Panama. Normal water quality in all zones was good, with 97% of routine water quality grab samples from the ...

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.

Wave-number spectra and intermittency in the terrestrial foreshock region.

Science.gov (United States)

Narita, Y; Glassmeier, K-H; Treumann, R A

2006-11-10

Wave-number spectra of magnetic field fluctuations are directly determined in the terrestrial foreshock region (upstream of a quasiparallel collisionless shock wave) using four-point Cluster spacecraft measurements. The spectral curve is characterized by three ranges reminiscent of turbulence: energy injection, inertial, and dissipation range. The spectral index for the inertial range spectrum is close to Kolmogorov's slope, -5/3. On the other hand, the fluctuations are highly anisotropic and intermittent perpendicular to the mean magnetic field direction. These results suggest that the foreshock is in a weakly turbulent and intermittent state in which parallel propagating Alfvén waves interact with one another, resulting in the phase coherence or the intermittency.

ANESTHETIC MANAGEMENT FOR A PATIENT WITH ACUTE INTERMITTENT PORPHYRIA

Directory of Open Access Journals (Sweden)

Nenad Savić

2010-09-01

Full Text Available Acute intermittent porphyria is a rare metabolic disorder resulting from a partial deficiency of porphobilinogen deaminase, enzyme in the heme biosynthetic pathway. Its inheritance is autosomal dominant. A deficiency of porphobilinogen deaminase is not sufficient by its self to produce acute intermittent porphyria, and other activating factors must also be present. These include some drugs, hormones, infection, injury and alcohol. Besides others, anesthetics have been implicated in the triggering of a number of severe porphyric reactions. Although there is no clinical evidence, the fear of hypothesized porphyrinogenicity of repetitive anesthetics exposures still remains. Despite these doubts, we report here the case of uneventful repeated exposure to anesthetics in a patient suffering from acute intermittent porphyria, within a fifteen- month period. On both occasions, the patient was safely exposed to certain anesthetics included: propofol, sevoflurane, rocuronium, midazolam and fentanyl.

On the degrees-of-freedom of the MIMO three-way channel with intermittent connectivity

KAUST Repository

Chaaban, Anas

2017-08-29

The degrees-of-freedom (DoF) of the multi-antenna three-way channel (3WC) with an intermittent node is studied. Special attention is given to the impact of adaptation when the intermittent node has the largest number of antennas. A non-adaptive transmission scheme based on interference alignment, zero-forcing, and erasure-channel treatment is proposed, and its corresponding DoF region is derived. Then, it is shown that this scheme achieves the sum-DoF of the intermittent channel, in addition to the DoF region of the nonintermittent one. Thus, adaptation is not necessary from those perspectives. To the contrary, it is shown that adaptation is necessary for achieving the DoF region of the intermittent case. This is shown by deriving an outer bound for the intermittent channel with nonadaptive encoding, and proposing an adaptive scheme which achieves DoF tuples outside this bound. This highlights the importance of cooperation in this intermittent network.

Characterization of wind power resource and its intermittency

Science.gov (United States)

Gunturu, U. B.; Schlosser, C. A.

2011-12-01

Wind resource in the continental and offshore United States has been calculated and characterized using metrics that describe - apart from abundance - its availability, persistence and intermittency. The Modern Era Retrospective-Analysis for Research and Applications (MERRA) boundary layer flux data has been used to construct wind power density profiles at 50, 80, 100 and 120 m turbine hub heights. The wind power density estimates at 50 m are qualitatively similar to those in the US wind atlas developed by the National Renewable Energy Laboratory (NREL), but quantitatively a class less in some regions, but are within the limits of uncertainty. We also show that for long tailed distributions like those of the wind power density, the mean is an overestimation and median is a more robust metric for summary representation of wind power resource.Generally speaking, the largest and most available wind power density resources are found in off-shore regions of the Atlantic and Pacific coastline, and the largest on-shore resource potential lies in the central United States. However, the intermittency and widespread synchronicity of on-shore wind power density are substantial, and highlights areas where considerable back-up generation technologies will be required. Generation-duration curves are also presented for the independent systems operator (ISO) zones of the U.S. to highlight the regions with the largest capacity factor (MISO, ERCOT, and SWPP) as well as the periods and extent to which all ISOs contain no wind power and the potential benefits of aggregation on wind power intermittency in each region. The impact of raising the wind turbine hub height on metrics of abundance, persistence, variability and intermittency is analyzed. There is a general increase in availability and abundance of wind resource but there is also an increase in intermittency with respect to a 'usable wind power' crossing level in low resource regions. A similar perspective of wind resource for

Analysis of host genetic diversity and viral entry as sources of between-host variation in viral load

Science.gov (United States)

Wargo, Andrew R.; Kell, Alison M.; Scott, Robert J.; Thorgaard, Gary H.; Kurath, Gael

2012-01-01

Little is known about the factors that drive the high levels of between-host variation in pathogen burden that are frequently observed in viral infections. Here, two factors thought to impact viral load variability, host genetic diversity and stochastic processes linked with viral entry into the host, were examined. This work was conducted with the aquatic vertebrate virus, Infectious hematopoietic necrosis virus (IHNV), in its natural host, rainbow trout. It was found that in controlled in vivo infections of IHNV, a suggestive trend of reduced between-fish viral load variation was observed in a clonal population of isogenic trout compared to a genetically diverse population of out-bred trout. However, this trend was not statistically significant for any of the four viral genotypes examined, and high levels of fish-to-fish variation persisted even in the isogenic trout population. A decrease in fish-to-fish viral load variation was also observed in virus injection challenges that bypassed the host entry step, compared to fish exposed to the virus through the natural water-borne immersion route of infection. This trend was significant for three of the four virus genotypes examined and suggests host entry may play a role in viral load variability. However, high levels of viral load variation also remained in the injection challenges. Together, these results indicate that although host genetic diversity and viral entry may play some role in between-fish viral load variation, they are not major factors. Other biological and non-biological parameters that may influence viral load variation are discussed.

Laboratory procedures to generate viral metagenomes.

Science.gov (United States)

Thurber, Rebecca V; Haynes, Matthew; Breitbart, Mya; Wegley, Linda; Rohwer, Forest

2009-01-01

This collection of laboratory protocols describes the steps to collect viruses from various samples with the specific aim of generating viral metagenome sequence libraries (viromes). Viral metagenomics, the study of uncultured viral nucleic acid sequences from different biomes, relies on several concentration, purification, extraction, sequencing and heuristic bioinformatic methods. No single technique can provide an all-inclusive approach, and therefore the protocols presented here will be discussed in terms of hypothetical projects. However, care must be taken to individualize each step depending on the source and type of viral-particles. This protocol is a description of the processes we have successfully used to: (i) concentrate viral particles from various types of samples, (ii) eliminate contaminating cells and free nucleic acids and (iii) extract, amplify and purify viral nucleic acids. Overall, a sample can be processed to isolate viral nucleic acids suitable for high-throughput sequencing in approximately 1 week.

Hepatitis A through E (Viral Hepatitis)

Science.gov (United States)

... Treatment Eating, Diet, & Nutrition Clinical Trials Wilson Disease Hepatitis (Viral) View or Print All Sections What is Viral Hepatitis? Viral hepatitis is an infection that causes liver inflammation ...

Intermittent hypoxia in childhood: the harmful consequences versus potential benefits of therapeutic uses

Directory of Open Access Journals (Sweden)

Tatiana V. Serebrovskaya

2015-05-01

Full Text Available Intermittent hypoxia often occurs in early infancy in both preterm and term infants and especially at 36 to 44 weeks postmenstrual age. These episodes of intermittent hypoxia could result from sleep-disordered breathing or may be temporally unrelated to apnea or bradycardia events. There are numerous reports indicating adverse effects of intermittent hypoxia on development, behavior, academic achievement and cognition in children with sleep apnea syndrome. It remains uncertain the exact causative relationship between the neurocognitive and behavioral morbidities and intermittent hypoxia and/or its associated sleep fragmentation. On the other hand, well-controlled and moderate intermittent hypoxia conditioning/training has been used in sick children for treating their various forms of bronchial asthma, allergic dermatoses, autoimmune thyroiditis, cerebral palsy, and obesity. This review article provides an updated and impartial analysis on the currently available evidence in supporting either side of the seemingly contradictory scenarios. We wish to stimulate a comprehensive understanding of such a complex physiological phenomenon as intermittent hypoxia, which may be accompanied by other confounding factors (e.g. hypercapnia, polycythemia, in order to prevent or reduce its harmful consequences, while maximize its potential utility as an effective therapeutic tool in pediatric patients.

Intermittent Domestic Water Supply: A Critical Review and Analysis of Causal-Consequential Pathways

Directory of Open Access Journals (Sweden)

S. E. Galaitsi

2016-06-01

Full Text Available Communities in many parts of the world, especially in developing countries, face obstacles in supplying continuous water to household consumers. Authorities often cite water scarcity as the cause, but we demonstrate that environmental constraints constitute only one aspect of a multi-dimensional problem. By asking what causes intermittent domestic water supply, this literature review (129 articles identifies 47 conditions of intermittent systems and the causal-consequential pathways between them that can reinforce intermittency. These pathways span several disciplines including engineering, government administration and anthropology, and when viewed together they (1 emphasize the human drivers of intermittency; (2 suggest generalized interventions; and (3 reveal a gap in the literature in terms of meaningful categorizations of the reliability of intermittent supplies. Based on the reliability of consumers’ water access, we propose three categories of intermittency—predictable, irregular, and unreliable—to facilitate comparisons between case studies and transfers of solutions.

Intermittent Aeration Suppresses Nitrite-Oxidizing Bacteria in Membrane-Aerated Biofilms: A Model-Based Explanation

DEFF Research Database (Denmark)

Ma, Yunjie; Domingo Felez, Carlos; Plósz, Benedek G.

2017-01-01

. On the basis of dissolved oxygen (DO), ammonium, nitrite, and nitrate profiles within the biofilm and in the bulk, a 1-dimensional nitrifying biofilm model was developed and calibrated. The model was utilized to explore the potential mechanisms of NOB suppression associated with intermittent aeration...... nitritation, strategies to suppress nitrite-oxidizing bacteria (NOB) are needed, which are ideally grounded on an understanding of underlying mechanisms. In this study, a nitrifying MABR was operated under intermittent aeration. During eight months of operation, AOB dominated, while NOB were suppressed...... during intermittent aeration was mostly explained by periodic inhibition caused by free ammonia due to periodic transient pH upshifts. Dissolved oxygen limitation did not govern NOB suppression. Different intermittent aeration strategies were then evaluated for nitritation success in intermittently...

Adsorption of viral particles from the blood plasma of patients with viral hepatitis on nanodiamonds.

Science.gov (United States)

Baron, A V; Osipov, N V; Yashchenko, S V; Kokotukha, Yu A; Baron, I J; Puzyr, A P; Olkhovskiy, I A; Bondar, V S

2016-07-01

Adsorption of viral particles from the blood plasma of patients with viral hepatitis B and C on modified nanodiamonds (MNDs) was shown in the in vitro experiments. PCR method showed the treatment of plasma with MNDs leads to a decrease in the viral load by 2-3 orders of magnitude or more in both cases studied. These results make it possible to predict the applicability of MNDs for the development of new technologies of hemodialysis and plasmapheresis for binding and removal of viral particles from the blood of infected patients.

Intermittent turbulence and oscillations in the stable boundary layer over land

NARCIS (Netherlands)

Wiel, van de B.

2002-01-01

As the title of this thesis indicates, our main subject of interest is: "Intermittent turbulence and oscillation in the stable boundary layer over land". As such, this theme connects the different chapters. Here, intermittent turbulence is defined as a sequence of events were 'burst' of

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.

Bacterial, viral and turbidity removal by intermittent slow sand filtration for household use in developing countries: experimental investigation and modeling.

Science.gov (United States)

Jenkins, Marion W; Tiwari, Sangam K; Darby, Jeannie

2011-11-15

A two-factor three-block experimental design was developed to permit rigorous evaluation and modeling of the main effects and interactions of sand size (d(10) of 0.17 and 0.52 mm) and hydraulic head (10, 20, and 30 cm) on removal of fecal coliform (FC) bacteria, MS2 bacteriophage virus, and turbidity, under two batch operating modes ('long' and 'short') in intermittent slow sand filters (ISSFs). Long operation involved an overnight pause time between feeding of two successive 20 L batches (16 h average batch residence time (RT)). Short operation involved no pause between two 20 L batch feeds (5h average batch RT). Conditions tested were representative of those encountered in developing country field settings. Over a ten week period, the 18 experimental filters were fed river water augmented with wastewater (influent turbidity of 5.4-58.6 NTU) and maintained with the wet harrowing method. Linear mixed modeling allowed systematic estimates of the independent marginal effects of each independent variable on each performance outcome of interest while controlling for the effects of variations in a batch's actual residence time, days since maintenance, and influent turbidity. This is the first study in which simultaneous measurement of bacteria, viruses and turbidity removal at the batch level over an extended duration has been undertaken with a large number of replicate units to permit rigorous modeling of ISSF performance variability within and across a range of likely filter design configurations and operating conditions. On average, the experimental filters removed 1.40 log fecal coliform CFU (SD 0.40 log, N=249), 0.54 log MS2 PFU (SD 0.42 log, N=245) and 89.0 percent turbidity (SD 6.9 percent, N=263). Effluent turbidity averaged 1.24 NTU (SD 0.53 NTU, N=263) and always remained below 3 NTU. Under the best performing design configuration and operating mode (fine sand, 10 cm head, long operation, initial HLR of 0.01-0.03 m/h), mean 1.82 log removal of bacteria (98

Faktor Risiko Non Viral Pada Karsinoma Nasofaring

Directory of Open Access Journals (Sweden)

Sukri Rahman

2015-09-01

Full Text Available Abstrak           Latar belakang: Karsinoma nasofaring adalah tumor ganas epitel nasofaring yang sampai saat ini penyebabnya belum diketahui, infeksi virus Epstein Barr dilaporkan sebagai faktor dominan terjadinya karsinoma nasofaring tetapi faktor non viral juga berperan untuk timbulnya keganasan nasofaring. Tujuan: Untuk mengetahui faktor non viral  yang dapat meningkatkan kejadian karsinoma nasofaring sehingga dapat mencegah dan menghindari faktor-faktor non viral tersebut. Tinjauan Pustaka: Karsinoma nasofaring merupakan tumor ganas epitel nasofaring yang penyebabnya berhubungan dengan faktor viral dan non viral diantaranya asap rokok, ikan asin, formaldehid, genetik, asap kayu bakar , debu kayu, infeksi kronik telinga hidung tenggorok, alkohol dan obat tradisional. Kesimpulan: Pembuktian secara klinis dan ilmiah terhadap faktor non viral sebagai penyebab timbulnya karsinoma nasofaring masih belum dapat dijelaskan secara pasti. Faktor non viral merupakan salah satu faktor risiko yang dapat meningkatkan angka kejadian timbulnya keganasan nasofaring Kata kunci: karsinoma nasofaring, faktor risiko, non viral AbstractBackground: Nasopharyngeal carcinoma is a malignant epithelial nasopharyngeal tumor that until now the cause still unknown, Epstein barr virus infection had reported as predominant occurance of nasopharyngeal carcinoma but non viral factors may also contribute to the onset of the incidence of nasopharyngeal malignancy. Purpose: To find non viral factors that may increase the incidence of nasopharyngel carcinoma in order to prevent and avoid non-viral factors Literature: Nasopharyngeal carcinoma is a malignant tumor that causes nasopharyngeal epithelium associated with viral and non-viral factors such as cigarette smoke, salt fish, formaldehyde, genetic, wood smoke ,wood dust, ear nose throat chronic infections, alcohol, and traditional medicine. Conclusion: Clinically and scientifically proving the non-viral factors as

Metabolism goes viral.

Science.gov (United States)

Miyake-Stoner, Shigeki J; O'Shea, Clodagh C

2014-04-01

Viral and cellular oncogenes converge in targeting critical protein interaction networks to reprogram the cellular DNA and protein replication machinery for pathological replication. In this issue, Thai et al. (2014) show that adenovirus E4ORF1 activates MYC glycolytic targets to induce a Warburg-like effect that converts glucose into nucleotides for viral replication. Copyright © 2014 Elsevier Inc. All rights reserved.

Obstructive sleep apnea and intermittent hypoxia increase expression of dual specificity phosphatase 1.

Science.gov (United States)

Hoffmann, Michal S; Singh, Prachi; Wolk, Robert; Narkiewicz, Krzysztof; Somers, Virend K

2013-12-01

Dual specificity phosphatase 1 (DUSP1) inhibits mitogen activated protein kinase activity, and is activated by several stimuli such as sustained hypoxia, oxidative stress, and hormones. However, the effect of intermittent hypoxia is not known. The aim of this study was to evaluate the role of intermittent hypoxia on DUSP1 expression, and to validate its role in a human model of intermittent hypoxia, as seen in obstructive sleep apnea (OSA). OSA is characterized by recurrent episodes of hypoxemia/reoxygenation and is a known risk factor for cardiovascular morbidity. In-vitro studies using human coronary artery endothelial cells (HCAEC) and ex-vivo studies using white blood cells isolated from healthy and OSA subjects. Intermittent hypoxia induced DUSP1 expression in human coronary artery endothelial cells (HCAEC), and in granulocytes isolated from healthy human subjects. Functionally, DUSP1 increased the expression and activity of manganese superoxide dismutase (MnSOD) in HCAEC. Further, significant increases in DUSP1 mRNA from total blood, and in DUSP1 protein in mononuclear cells and granulocytes isolated from OSA subjects, were observed in the early morning hours after one night of intermittent hypoxemia due to untreated OSA. This early-morning OSA-induced augmentation of DUSP1 gene expression was attenuated by continuous positive airway pressure (CPAP) treatment of OSA. Intermittent hypoxia increases MnSOD activity via increased DUSP1 expression in HCAEC. Similarly, overnight intermittent hypoxemia in patients with OSA induces expression of DUSP1, which may mediate increases of MnSOD expression and activity. This may contribute significantly to neutralizing the effects of reactive oxygen species, a consequence of the intermittent hypoxemia/reperfusion elicited by OSA. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

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

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...

Cost effectiveness of intermittent screening followed by treatment versus intermittent preventive treatment during pregnancy in West Africa

DEFF Research Database (Denmark)

Fernandes, Silke; Sicuri, Elisa; Halimatou, Diawara

2016-01-01

$/DALY averted. Simulations show that cost-effectiveness of ISTp-AL increases as the efficacy of IPTp-SP decreases, though the specific threshold at which ISTp-AL becomes cost-effective depends on assumptions about the contribution of bed nets to malaria control, bed net coverage and the willingness......-to-pay threshold used.  Conclusions: At SP efficacy levels currently observed in the trial settings it would not be cost-effective to switch from IPTp-SP to ISTp-AL, mainly due to the substantially higher costs of ISTp-AL and limited difference in outcomes. The modelling results indicate thresholds below which IPT......Background: Emergence of high-grade sulfadoxine-pyrimethamine (SP) resistance in parts of Africa has led to growing concerns about the efficacy of intermittent preventive treatment of malaria during pregnancy (IPTp) with SP. The incremental cost-effectiveness of intermittent screening and treatment...

Gene : CBRC-GGAL-02-0044 [SEVENS

Lifescience Database Archive (English)

Full Text Available e BLIP-II repeats protein (partial match) [Herminiimonas arsenicoxydans] emb|CAL62346.1| Putative BLIP-II re...peats protein (partial match) [Herminiimonas arsenicoxydans] 0.80 30% gnl|UG|Gga#S19183868 Gallus gallus cyc

Muscular soreness following prolonged intermittent high-intensity shuttle running.

Science.gov (United States)

Thompson, D; Nicholas, C W; Williams, C

1999-05-01

The aim of this study was to examine the impact of prolonged intermittent high-intensity shuttle running on soreness and markers of muscle damage. Sixteen males took part in the study, half of whom were assigned to a running group and half to a resting control group. The exercise protocol involved 90 min of intermittent shuttle running and walking (Loughborough Intermittent Shuttle Test: LIST), reflecting the activity pattern found in multiple-sprint sports such as soccer. Immediately after exercise, there was a significant increase (P < 0.05) in serum activities of creatine kinase and aspartate aminotransferase, and values remained above baseline for 48 h (P < 0.05). Median peak activities of creatine kinase and aspartate aminotransferase occurred 24 h post-exercise and were 774 and 43 U x l(-1), respectively. The intensity of general muscle soreness, and in the specific muscles investigated, was greater than baseline for 72 h after the shuttle test (P < 0.05), peaking 24-48 h post-exercise (P < 0.05). Muscle soreness was not correlated with either creatine kinase or aspartate aminotransferase activity. Soreness was most frequently reported in the hamstrings. Neither soreness nor serum enzyme activity changed in the controls over the 4 day observation period. It appears that unaccustomed performance of prolonged intermittent shuttle running produces a significant increase in both soreness and markers of muscle damage.

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.

The problem of intermittency of renewable energies: solar and wind energy

International Nuclear Information System (INIS)

Livet, Frederic

2011-01-01

As solar and wind energies are to be intensively developed but are intermittent, more or less regular and unpredictable, the author first discusses methods which are presently used to manage this intermittency in various European countries. He also discusses the various methods which are proposed to compensate this intermittency: hydraulic storage, hydrogen-based storage, batteries, and large scale interconnections. He gives and comments cost assessments of the various proposed methods and of capacities. He shows that various measures which are discussed at the European level to promote renewable energies and to promote electricity exchanges will in fact result in a three times higher price of electricity for individuals

Demographics and frequency of the intermittently upturned omentum at CT

Energy Technology Data Exchange (ETDEWEB)

Penn, Alex; Wang, Wilbur; Wang, Zhen Jane; Yee, Judy; Webb, Emily M.; Yeh, Benjamin M., E-mail: ben.yeh@ucsf.edu

2013-11-01

Objectives: To describe the demographics and frequency of the intermittently upturned omentum at CT. Methods: We retrospectively reviewed abdominal CT scans of 336 consecutive patients (189 men and 147 women) who were imaged between June 1 and June 17, 2010 and who had prior comparison scans. Readers recorded the presence or absence of an intermittently upturned omentum, defined as a thick rind of fat interposed between the liver and the anterior abdominal wall seen on one but not the other scan. At chart review, we recorded patient demographics and other clinical characteristics (prior surgical history, presence of cirrhosis). Results: An intermittently upturned omentum was found in 10 of 336 (3.0%) patients. An intermittently upturned omentum was seen more commonly in men than in women (9 of 189 men, or 4.8% versus 1 of 147 women, or 0.7%, p = 0.047) and in cirrhotics (4 of 37 cirrhotics, or 10.8% versus 6 of 299 non-cirrhotics, or 2.0%, p = 0.023). In a sub-analysis of patients without prior abdominal surgery, this finding was again seen more commonly in men than women (7 of 163 men, or 4.3% versus 0 of 134 women, or 0%, p = 0.018) and in cirrhotics (3 of 33 cirrhotics, or 9.1% versus 4 of 264 non-cirrhotics, or 1.5%, p = 0.032). Conclusions: An intermittently upturned omentum is not uncommon and is more frequently seen in men and in patients with cirrhosis who may have a larger anterior hepatic space.

Demographics and frequency of the intermittently upturned omentum at CT

International Nuclear Information System (INIS)

Penn, Alex; Wang, Wilbur; Wang, Zhen Jane; Yee, Judy; Webb, Emily M.; Yeh, Benjamin M.

2013-01-01

Objectives: To describe the demographics and frequency of the intermittently upturned omentum at CT. Methods: We retrospectively reviewed abdominal CT scans of 336 consecutive patients (189 men and 147 women) who were imaged between June 1 and June 17, 2010 and who had prior comparison scans. Readers recorded the presence or absence of an intermittently upturned omentum, defined as a thick rind of fat interposed between the liver and the anterior abdominal wall seen on one but not the other scan. At chart review, we recorded patient demographics and other clinical characteristics (prior surgical history, presence of cirrhosis). Results: An intermittently upturned omentum was found in 10 of 336 (3.0%) patients. An intermittently upturned omentum was seen more commonly in men than in women (9 of 189 men, or 4.8% versus 1 of 147 women, or 0.7%, p = 0.047) and in cirrhotics (4 of 37 cirrhotics, or 10.8% versus 6 of 299 non-cirrhotics, or 2.0%, p = 0.023). In a sub-analysis of patients without prior abdominal surgery, this finding was again seen more commonly in men than women (7 of 163 men, or 4.3% versus 0 of 134 women, or 0%, p = 0.018) and in cirrhotics (3 of 33 cirrhotics, or 9.1% versus 4 of 264 non-cirrhotics, or 1.5%, p = 0.032). Conclusions: An intermittently upturned omentum is not uncommon and is more frequently seen in men and in patients with cirrhosis who may have a larger anterior hepatic space

29 CFR 825.203 - Scheduling of intermittent or reduced schedule leave.

Science.gov (United States)

2010-07-01

... leave intermittently or on a reduced leave schedule for planned medical treatment, then the employee... 29 Labor 3 2010-07-01 2010-07-01 false Scheduling of intermittent or reduced schedule leave. 825... OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Employee Leave Entitlements Under the...

Boldness and intermittent locomotion in the bluegill sunfish, Lepomis macrochirus

OpenAIRE

Alexander D.M. Wilson; Jean-Guy J. Godin

2009-01-01

Intermittent locomotion, characterized by moves interspersed with pauses, is a common pattern of locomotion in animals, but its ecological and evolutionary significance relative to continuous locomotion remains poorly understood. Although many studies have examined individual differences in both intermittent locomotion and boldness separately, to our knowledge, no study to date has investigated the relationship between these 2 traits. Characterizing and understanding this relationship is impo...

The intermittency of vector fields and random-number generators

Science.gov (United States)

Kalinin, A. O.; Sokoloff, D. D.; Tutubalin, V. N.

2017-09-01

We examine how well natural random-number generators can reproduce the intermittency phenomena that arise in the transfer of vector fields in random media. A generator based on the analysis of financial indices is suggested as the most promising random-number generator. Is it shown that even this generator, however, fails to reproduce the phenomenon long enough to confidently detect intermittency, while the C++ generator successfully solves this problem. We discuss the prospects of using shell models of turbulence as the desired generator.

Muscle involvement during intermittent contraction patterns with different target force feedback modes

DEFF Research Database (Denmark)

Sjøgaard, G; Jørgensen, L V; Ekner, D

2000-01-01

and following 30 min of intermittent contractions showed larger fatigue development with proprioceptive feedback than visual feedback. Also rating of perceived exertion increased more during proprioceptive feedback than visual feedback. This may in part be explained by small differences in the mechanics during......: Feedback mode significantly effects the muscle involvement and fatigue during intermittent contractions. RelevanceIntermittent contractions are common in many work places and various feedback modes are being given regarding work requirements. The choice of feedback may significantly affect the muscle load...... and consequently the development muscle fatigue and disorders....

Intermittent Hypoxia in Childhood: The Harmful Consequences Versus Potential Benefits of Therapeutic Uses

OpenAIRE

Serebrovskaya, Tatiana V.; Xi, Lei

2015-01-01

Intermittent hypoxia often occurs in early infancy in both preterm and term infants and especially at 36 to 44 weeks postmenstrual age. These episodes of intermittent hypoxia could result from sleep-disordered breathing or may be temporally unrelated to apnea or bradycardia events. There are numerous reports indicating adverse effects of intermittent hypoxia on development, behavior, academic achievement and cognition in children with sleep apnea syndrome. It remains uncertain the exact causa...

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.

EVOLUTION OF INTERMITTENCY IN THE SLOW AND FAST SOLAR WIND BEYOND THE ECLIPTIC PLANE

International Nuclear Information System (INIS)

Wawrzaszek, A.; Macek, W. M.; Echim, M.; Bruno, R.

2015-01-01

We study intermittency as a departure from self-similarity of the solar wind magnetic turbulence and investigate the evolution with the heliocentric distance and latitude. We use data from the Ulysses spacecraft measured during two solar minima (1997–1998 and 2007–2008) and one solar maximum (1999–2001). In particular, by modeling a multifractal spectrum, we revealed the intermittent character of turbulence in the small-scale fluctuations of the magnetic field embedded in the slow and fast solar wind. Generally, at small distances from the Sun, in both the slow and fast solar wind, we observe the high degree of multifractality (intermittency) that decreases somewhat slowly with distance and slowly with latitude. The obtained results seem to suggest that generally intermittency in the solar wind has a solar origin. However, the fast and slow streams, shocks, and other nonlinear interactions can only be considered as the drivers of the intermittent turbulence. It seems that analysis shows that turbulence beyond the ecliptic plane evolves too slowly to maintain the intermittency with the distance and latitude. Moreover, we confirm that the multifractality and intermittency are at a lower level than in the ecliptic, as well as the existence of symmetry with respect to the ecliptic plane, suggesting that there are similar turbulent properties observed in the two hemispheres

EVOLUTION OF INTERMITTENCY IN THE SLOW AND FAST SOLAR WIND BEYOND THE ECLIPTIC PLANE

Energy Technology Data Exchange (ETDEWEB)

Wawrzaszek, A.; Macek, W. M. [Space Research Centre, Polish Academy of Sciences, Warsaw (Poland); Echim, M. [The Belgian Institute for Space Aeronomy, Brussels (Belgium); Bruno, R., E-mail: anna.wawrzaszek@cbk.waw.pl, E-mail: marius.echim@oma.be, E-mail: macek@cbk.waw.pl, E-mail: roberto.bruno@iaps.inaf.it [Institute for Space Astrophysics and Planetology, Roma (Italy)

2015-12-01

We study intermittency as a departure from self-similarity of the solar wind magnetic turbulence and investigate the evolution with the heliocentric distance and latitude. We use data from the Ulysses spacecraft measured during two solar minima (1997–1998 and 2007–2008) and one solar maximum (1999–2001). In particular, by modeling a multifractal spectrum, we revealed the intermittent character of turbulence in the small-scale fluctuations of the magnetic field embedded in the slow and fast solar wind. Generally, at small distances from the Sun, in both the slow and fast solar wind, we observe the high degree of multifractality (intermittency) that decreases somewhat slowly with distance and slowly with latitude. The obtained results seem to suggest that generally intermittency in the solar wind has a solar origin. However, the fast and slow streams, shocks, and other nonlinear interactions can only be considered as the drivers of the intermittent turbulence. It seems that analysis shows that turbulence beyond the ecliptic plane evolves too slowly to maintain the intermittency with the distance and latitude. Moreover, we confirm that the multifractality and intermittency are at a lower level than in the ecliptic, as well as the existence of symmetry with respect to the ecliptic plane, suggesting that there are similar turbulent properties observed in the two hemispheres.

Viral Haemorrhagic Septicaemia Virus

DEFF Research Database (Denmark)

Olesen, Niels Jørgen; Skall, Helle Frank

2013-01-01

This chapter covers the genetics (genotypes and serotypes), clinical signs, host species, transmission, prevalence, diagnosis, control and prevention of viral haemorrhagic septicaemia virus.......This chapter covers the genetics (genotypes and serotypes), clinical signs, host species, transmission, prevalence, diagnosis, control and prevention of viral haemorrhagic septicaemia virus....

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.

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.

Assembly of viral genomes from metagenomes

NARCIS (Netherlands)

S.L. Smits (Saskia); R. Bodewes (Rogier); A. Ruiz-Gonzalez (Aritz); V. Baumgärtner (Volkmar); M.P.G. Koopmans D.V.M. (Marion); A.D.M.E. Osterhaus (Albert); A. Schürch (Anita)

2014-01-01

textabstractViral infections remain a serious global health issue. Metagenomic approaches are increasingly used in the detection of novel viral pathogens but also to generate complete genomes of uncultivated viruses. In silico identification of complete viral genomes from sequence data would allow

Viral commercials: the consumer as marketeer

NARCIS (Netherlands)

Ketelaar, P.E.; Lucassen, P.; Kregting, G.H.J.

2010-01-01

Research into the reasons why consumers pass along viral commercials: their motives, the content characteristics of viral commercials and the medium context in which viral commercials appear. Based on the uses and gratifications perspective this study has determined which motives of consumers,

Intermittent characteristics in coupling between turbulence and zonal flows

International Nuclear Information System (INIS)

Fujisawa, A; Shimizu, A; Nakano, H; Ohshima, S; Itoh, K; Nagashima, Y; Itoh, S-I; Iguchi, H; Yoshimura, Y; Minami, T; Nagaoka, K; Takahashi, C; Kojima, M; Nishimura, S; Isobe, M; Suzuki, C; Akiyama, T; Ido, T; Matsuoka, K; Okamura, S; Diamond, P H

2007-01-01

An extended application of Gabour's wavelet to bicoherence analysis succeeds in resolving the instantaneous structure of three wave couplings between disparate scale electric field fluctuations in the high temperature core in a toroidal plasma device named the compact helical system. The obtained results quantify an intermittent linkage between turbulence and zonal flows-a highlighted issue in the present plasma research. This is the first demonstration that the intermittent nature of the three wave coupling should underlie the turbulence power modulation due to zonal flows

Viral Infection in Renal Transplant Recipients

Directory of Open Access Journals (Sweden)

Jovana Cukuranovic

2012-01-01

Full Text Available Viruses are among the most common causes of opportunistic infection after transplantation. The risk for viral infection is a function of the specific virus encountered, the intensity of immune suppression used to prevent graft rejection, and other host factors governing susceptibility. Although cytomegalovirus is the most common opportunistic pathogen seen in transplant recipients, numerous other viruses have also affected outcomes. In some cases, preventive measures such as pretransplant screening, prophylactic antiviral therapy, or posttransplant viral monitoring may limit the impact of these infections. Recent advances in laboratory monitoring and antiviral therapy have improved outcomes. Studies of viral latency, reactivation, and the cellular effects of viral infection will provide clues for future strategies in prevention and treatment of viral infections. This paper will summarize the major viral infections seen following transplant and discuss strategies for prevention and management of these potential pathogens.

NCBI nr-aa BLAST: CBRC-GGAL-02-0044 [SEVENS

Lifescience Database Archive (English)

Full Text Available coxydans] emb|CAL62346.1| Putative BLIP-II repeats protein (partial match) [Herminiimonas arsenicoxydans] YP_001100469.1 0.80 30% ... ...CBRC-GGAL-02-0044 ref|YP_001100469.1| Putative BLIP-II repeats protein (partial match) [Herminiimonas arseni

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

The stochastic dynamics of intermittent porescale particle motion

Science.gov (United States)

Dentz, Marco; Morales, Veronica; Puyguiraud, Alexandre; Gouze, Philippe; Willmann, Matthias; Holzner, Markus

2017-04-01

Numerical and experimental data for porescale particle dynamics show intermittent patterns in Lagrangian velocities and accelerations, which manifest in long time intervals of low and short durations of high velocities [1, 2]. This phenomenon is due to the spatial persistence of particle velocities on characteristic heterogeneity length scales. In order to systematically quantify these behaviors and extract the stochastic dynamics of particle motion, we focus on the analysis of Lagrangian velocities sampled equidistantly along trajectories [3]. This method removes the intermittency observed under isochrone sampling. The space-Lagrangian velocity series can be quantified by a Markov process that is continuous in distance along streamline. It is fully parameterized in terms of the flux-weighted Eulerian velocity PDF and the characteristic pore-length. The resulting stochastic particle motion describes a continuous time random walk (CTRW). This approach allows for the process based interpretation of experimental and numerical porescale velocity, acceleration and displacement data. It provides a framework for the characterization and upscaling of particle transport and dispersion from the pore to the Darcy-scale based on the medium geometry and Eulerian flow attributes. [1] P. De Anna, T. Le Borgne, M. Dentz, A.M. Tartakovsky, D. Bolster, and P. Davy, "Flow intermittency, dispersion, and correlated continuous time random walks in porous media," Phys. Rev. Lett. 110, 184502 (2013). [2] M. Holzner, V. L. Morales, M. Willmann, and M. Dentz, "Intermittent Lagrangian velocities and accelerations in three- dimensional porous medium flow," Phys. Rev. E 92, 013015 (2015). [3] M. Dentz, P. K. Kang, A. Comolli, T. Le Borgne, and D. R. Lester, "Continuous time random walks for the evolution of Lagrangian velocities," Phys. Rev. Fluids (2016).

Circulating, cell-free DNA as a marker for exercise load in intermittent sports

OpenAIRE

Haller, Nils; Helmig, Susanne; Taenny, Pascal; Petry, Julian; Schmidt, Sebastian; Simon, Perikles

2018-01-01

Background Attempts to establish a biomarker reflecting individual player load in intermittent sports such as football have failed so far. Increases in circulating DNA (cfDNA) have been demonstrated in various endurance sports settings. While it has been proposed that cfDNA could be a suitable marker for player load in intermittent sports, the effects on cfDNA of repeated sprinting as an essential feature in intermittent sports are unknown. For the first time, we assessed both alterations of ...

Intermittent dynamics of nonlinear resistive tearing modes at extremely high magnetic Reynolds number

International Nuclear Information System (INIS)

Miyoshi, Takahiro; Becchaku, Masahiro; Kusano, Kanya

2008-01-01

Nonlinear dynamics of the resistive tearing instability in high magnetic Reynolds number (R m ) plasmas is studied by newly developing an accurate and robust resistive magnetohydrodynamic (MHD) scheme. The results show that reconnection processes strongly depend on R m . Particularly, in a high R m case, small-scale plasmoids induced by a secondary instability are intermittently generated and ejected accompanied by fast shocks. According to the intermittent processes, the reconnection rate increases intermittently at a later nonlinear stage. (author)

Structure functions and intermittency in ionospheric plasma turbulence

Directory of Open Access Journals (Sweden)

L. Dyrud

2008-11-01

Full Text Available Low frequency electrostatic turbulence in the ionospheric E-region is studied by means of numerical and experimental methods. We use the structure functions of the electrostatic potential as a diagnostics of the fluctuations. We demonstrate the inherently intermittent nature of the low level turbulence in the collisional ionospheric plasma by using results for the space-time varying electrostatic potential from two dimensional numerical simulations. An instrumented rocket can not directly detect the one-point potential variation, and most measurements rely on records of potential differences between two probes. With reference to the space observations we demonstrate that the results obtained by potential difference measurements can differ significantly from the one-point results. It was found, in particular, that the intermittency signatures become much weaker, when the proper rocket-probe configuration is implemented. We analyze also signals from an actual ionospheric rocket experiment, and find a reasonably good agreement with the appropriate simulation results, demonstrating again that rocket data, obtained as those analyzed here, are unlikely to give an adequate representation of intermittent features of the low frequency ionospheric plasma turbulence for the given conditions.

Viral Metagenomics: MetaView Software

Energy Technology Data Exchange (ETDEWEB)

Zhou, C; Smith, J

2007-10-22

The purpose of this report is to design and develop a tool for analysis of raw sequence read data from viral metagenomics experiments. The tool should compare read sequences of known viral nucleic acid sequence data and enable a user to attempt to determine, with some degree of confidence, what virus groups may be present in the sample. This project was conducted in two phases. In phase 1 we surveyed the literature and examined existing metagenomics tools to educate ourselves and to more precisely define the problem of analyzing raw read data from viral metagenomic experiments. In phase 2 we devised an approach and built a prototype code and database. This code takes viral metagenomic read data in fasta format as input and accesses all complete viral genomes from Kpath for sequence comparison. The system executes at the UNIX command line, producing output that is stored in an Oracle relational database. We provide here a description of the approach we came up with for handling un-assembled, short read data sets from viral metagenomics experiments. We include a discussion of the current MetaView code capabilities and additional functionality that we believe should be added, should additional funding be acquired to continue the work.

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.

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.

Acute Pancreatitis in acute viral hepatitis

Directory of Open Access Journals (Sweden)

S K.C.

2011-03-01

Full Text Available Introduction: The association of acute viral hepatitis and acute pancreatitis is well described. This study was conducted to find out the frequency of pancreatic involvement in acute viral hepatitis in the Nepalese population. Methods: Consecutive patients of acute viral hepatitis presenting with severe abdominal pain between January 2005 and April 2010 were studied. Patients with history of significant alcohol consumption and gall stones were excluded. Acute viral hepatitis was diagnosed by clinical examination, liver function test, ultrasound examination and confirmed by viral serology. Pancreatitis was diagnosed by clinical presentation, biochemistry, ultrasound examination and CT scan. Results: Severe abdominal pain was present in 38 of 382 serologically-confirmed acute viral hepatitis patients. Twenty five patients were diagnosed to have acute pancreatitis. The pancreatitis was mild in 14 and severe in 11 patients. The etiology of pancreatitis was hepatitis E virus in 18 and hepatitis A virus in 7 patients. Two patients died of complications secondary to shock. The remaining patients recovered from both pancreatitis and hepatitis on conservative treatment. Conclusions: Acute pancreatitis occurred in 6.5 % of patients with acute viral hepatitis. Cholelithiasis and gastric ulcers are the other causes of severe abdominal pain. The majority of the patients recover with conservative management. Keywords: acute viral hepatitis, acute pancreatitis, pain abdomen, hepatitis E, hepatitis A, endemic zone

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.

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.

Dealing with uncertainty in modeling intermittent water supply

Science.gov (United States)

Lieb, A. M.; Rycroft, C.; Wilkening, J.

2015-12-01

Intermittency in urban water supply affects hundreds of millions of people in cities around the world, impacting water quality and infrastructure. Building on previous work to dynamically model the transient flows in water distribution networks undergoing frequent filling and emptying, we now consider the hydraulic implications of uncertain input data. Water distribution networks undergoing intermittent supply are often poorly mapped, and household metering frequently ranges from patchy to nonexistent. In the face of uncertain pipe material, pipe slope, network connectivity, and outflow, we investigate how uncertainty affects dynamical modeling results. We furthermore identify which parameters exert the greatest influence on uncertainty, helping to prioritize data collection.

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.

Optimal Integration of Intermittent Renewables: A System LCOE Stochastic Approach

Directory of Open Access Journals (Sweden)

Carlo Lucheroni

2018-03-01

Full Text Available We propose a system level approach to value the impact on costs of the integration of intermittent renewable generation in a power system, based on expected breakeven cost and breakeven cost risk. To do this, we carefully reconsider the definition of Levelized Cost of Electricity (LCOE when extended to non-dispatchable generation, by examining extra costs and gains originated by the costly management of random power injections. We are thus lead to define a ‘system LCOE’ as a system dependent LCOE that takes properly into account intermittent generation. In order to include breakeven cost risk we further extend this deterministic approach to a stochastic setting, by introducing a ‘stochastic system LCOE’. This extension allows us to discuss the optimal integration of intermittent renewables from a broad, system level point of view. This paper thus aims to provide power producers and policy makers with a new methodological scheme, still based on the LCOE but which updates this valuation technique to current energy system configurations characterized by a large share of non-dispatchable production. Quantifying and optimizing the impact of intermittent renewables integration on power system costs, risk and CO 2 emissions, the proposed methodology can be used as powerful tool of analysis for assessing environmental and energy policies.

Viral O-GalNAc peptide epitopes

DEFF Research Database (Denmark)

Olofsson, Sigvard; Blixt, Klas Ola; Bergström, Tomas

2016-01-01

Viral envelope glycoproteins are major targets for antibodies that bind to and inactivate viral particles. The capacity of a viral vaccine to induce virus-neutralizing antibodies is often used as a marker for vaccine efficacy. Yet the number of known neutralization target epitopes is restricted o...

Analyzing the Efficiency of Introduction of the Intermittent Heating Mode

Science.gov (United States)

Anisimova, E.; Shcherbak, A.

2017-11-01

The efficiency of introduction of an optimal intermittent heating mode for a service center building in Chelyabinsk is estimated. The optimal intermittent heating mode ensures heat energy saving while maintaining the required microclimate parameters. The graphical dependencies of the amount of heat energy saving on the heat retention of the building and the outdoor air temperature are shown. The fundamental formulas which were the basis for calculating the periods of cooling, warming and expenditures of heat energy for the two heating modes are given. The literature on the issue is reviewed, the main points, advantages and disadvantages in the works of both Russian and foreign authors are revealed. The calculation was carried out in compliance with the modern state standards and regulatory documents. The capital costs of a system construction with an intermittent heating mode are determined.

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.

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.)

Multi-scale magnetic field intermittence in the plasma sheet

Directory of Open Access Journals (Sweden)

Z. Vörös

2003-09-01

Full Text Available This paper demonstrates that intermittent magnetic field fluctuations in the plasma sheet exhibit transitory, localized, and multi-scale features. We propose a multifractal-based algorithm, which quantifies intermittence on the basis of the statistical distribution of the "strength of burstiness", estimated within a sliding window. Interesting multi-scale phenomena observed by the Cluster spacecraft include large-scale motion of the current sheet and bursty bulk flow associated turbulence, interpreted as a cross-scale coupling (CSC process.Key words. Magnetospheric physics (magnetotail; plasma sheet – Space plasma physics (turbulence

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.

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.

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

Circuit implementation and multiform intermittency in a hyper-chaotic model extended from the Lorenz system

International Nuclear Information System (INIS)

Shi-Jian, Cang; Zeng-Qiang, Chen; Wen-Juan, Wu

2009-01-01

This paper presents a non-autonomous hyper-chaotic system, which is formed by adding a periodic driving signal to a four-dimensional chaotic model extended from the Lorenz system. The resulting non-autonomous hyper-chaotic system can display any dynamic behaviour among the periodic orbits, intermittency, chaos and hyper-chaos by controlling the frequency of the periodic signal. The phenomenon has been well demonstrated by numerical simulations, bifurcation analysis and electronic circuit realization. Moreover, the system is concrete evidence for the presence of Pomeau–Manneville Type-I intermittency and crisis-induced intermittency. The emergence of a different type of intermittency is similarly subjected to the frequency of periodic forcing. By statistical analysis, power scaling laws consisting in different intermittency are obtained for the lifetime in the laminar state between burst states

Detection of feline coronavirus in cheetah (Acinonyx jubatus) feces by reverse transcription-nested polymerase chain reaction in cheetahs with variable frequency of viral shedding.

Science.gov (United States)

Gaffney, Patricia M; Kennedy, Melissa; Terio, Karen; Gardner, Ian; Lothamer, Chad; Coleman, Kathleen; Munson, Linda

2012-12-01

Cheetahs (Acinonyx jubatus) are a highly threatened species because of habitat loss, human conflict, and high prevalence of disease in captivity. An epidemic of feline infectious peritonitis and concern for spread of infectious disease resulted in decreased movement of cheetahs between U.S. zoological facilities for managed captive breeding. Identifying the true feline coronavirus (FCoV) infection status of cheetahs is challenging because of inconsistent correlation between seropositivity and fecal viral shedding. Because the pattern of fecal shedding of FCoV is unknown in cheetahs, this study aimed to assess the frequency of detectable fecal viral shedding in a 30-day period and to determine the most efficient fecal sampling strategy to identify cheetahs shedding FCoV. Fecal samples were collected from 16 cheetahs housed at seven zoological facilities for 30 to 46 consecutive days; the samples were evaluated for the presence of FCoV by reverse transcription-nested polymerase chain reaction (RT-nPCR). Forty-four percent (7/16) of cheetahs had detectable FCoV in feces, and the proportion of positive samples for individual animals ranged from 13 to 93%. Cheetahs shed virus persistently, intermittently, or rarely over 30-46 days. Fecal RT-nPCR results were used to calculate the probability of correctly identifying a cheetah known to shed virus given multiple hypothetical fecal collection schedules. The most efficient hypothetical fecal sample collection schedule was evaluation of five individual consecutive fecal samples, resulting in a 90% probability of identifying a known shedder. Demographic and management risk factors were not significantly associated (P cheetahs shed virus intermittently to rarely, fecal sampling schedules meant to identify all known shedders would be impractical with current tests and eradication of virus from the population unreasonable. Managing the captive population as endemically infected with FCoV may be a more feasible approach.

Viral infections in transplant recipients.

Science.gov (United States)

Razonable, R R; Eid, A J

2009-12-01

Solid organ and hematopoietic stem cell transplant recipients are uniquely predisposed to develop clinical illness, often with increased severity, due to a variety of common and opportunistic viruses. Patients may acquire viral infections from the donor (donor-derived infections), from reactivation of endogenous latent virus, or from the community. Herpes viruses, most notably cytomegalovirus and Epstein Barr virus, are the most common among opportunistic viral pathogens that cause infection after solid organ and hematopoietic stem cell transplantation. The polyoma BK virus causes opportunistic clinical syndromes predominantly in kidney and allogeneic hematopoietic stem cell transplant recipients. The agents of viral hepatitis B and C present unique challenges particularly among liver transplant recipients. Respiratory viral illnesses due to influenza, respiratory syncytial virus, and parainfluenza virus may affect all types of transplant recipients, although severe clinical disease is observed more commonly among lung and allogeneic hematopoietic stem cell transplant recipients. Less common viral infections affecting transplant recipients include those caused by adenoviruses, parvovirus B19, and West Nile virus. Treatment for viruses with proven effective antiviral drug therapies should be complemented by reduction in the degree of immunosuppression. For others with no proven antiviral drugs for therapy, reduction in the degree of immunosuppression remains as the sole effective strategy for management. Prevention of viral infections is therefore of utmost importance, and this may be accomplished through vaccination, antiviral strategies, and aggressive infection control measures.

[Viral hepatitis in travellers].

Science.gov (United States)

Abreu, Cândida

2007-01-01

Considering the geographical asymmetric distribution of viral hepatitis A, B and E, having a much higher prevalence in the less developed world, travellers from developed countries are exposed to a considerable and often underestimated risk of hepatitis infection. In fact a significant percentage of viral hepatitis occurring in developed countries is travel related. This results from globalization and increased mobility from tourism, international work, humanitarian and religious missions or other travel related activities. Several studies published in Europe and North America shown that more than 50% of reported cases of hepatitis A are travel related. On the other hand frequent outbreaks of hepatitis A and E in specific geographic areas raise the risk of infection in these restricted zones and that should be clearly identified. Selected aspects related with the distribution of hepatitis A, B and E are reviewed, particularly the situation in Portugal according to the published studies, as well as relevant clinical manifestations and differential diagnosis of viral hepatitis. Basic prevention rules considering enteric transmitted hepatitis (hepatitis A and hepatitis E) and parenteral transmitted (hepatitis B) are reviewed as well as hepatitis A and B immunoprophylaxis. Common clinical situations and daily practice "pre travel" advice issues are discussed according to WHO/CDC recommendations and the Portuguese National Vaccination Program. Implications from near future availability of a hepatitis E vaccine, a currently in phase 2 trial, are highlighted. Potential indications for travellers to endemic countries like India, Nepal and some regions of China, where up to 30% of sporadic cases of acute viral hepatitis are caused by hepatitis E virus, are considered. Continued epidemiological surveillance for viral hepatitis is essential to recognize and control possible outbreaks, but also to identify new viral hepatitis agents that may emerge as important global health

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.

Assembly of viral genomes from metagenomes

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Saskia L Smits

2014-12-01

Full Text Available Viral infections remain a serious global health issue. Metagenomic approaches are increasingly used in the detection of novel viral pathogens but also to generate complete genomes of uncultivated viruses. In silico identification of complete viral genomes from sequence data would allow rapid phylogenetic characterization of these new viruses. Often, however, complete viral genomes are not recovered, but rather several distinct contigs derived from a single entity, some of which have no sequence homology to any known proteins. De novo assembly of single viruses from a metagenome is challenging, not only because of the lack of a reference genome, but also because of intrapopulation variation and uneven or insufficient coverage. Here we explored different assembly algorithms, remote homology searches, genome-specific sequence motifs, k-mer frequency ranking, and coverage profile binning to detect and obtain viral target genomes from metagenomes. All methods were tested on 454-generated sequencing datasets containing three recently described RNA viruses with a relatively large genome which were divergent to previously known viruses from the viral families Rhabdoviridae and Coronaviridae. Depending on specific characteristics of the target virus and the metagenomic community, different assembly and in silico gap closure strategies were successful in obtaining near complete viral genomes.

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.

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.

Intermittent fasting during Ramadan: does it affect sleep?

Science.gov (United States)

Bahammam, Ahmed S; Almushailhi, Khalid; Pandi-Perumal, Seithikurippu R; Sharif, Munir M

2014-02-01

Islamic intermittent fasting is distinct from regular voluntary or experimental fasting. We hypothesised that if a regimen of a fixed sleep-wake schedule and a fixed caloric intake is followed during intermittent fasting, the effects of fasting on sleep architecture and daytime sleepiness will be minimal. Therefore, we designed this study to objectively assess the effects of Islamic intermittent fasting on sleep architecture and daytime sleepiness. Eight healthy volunteers reported to the Sleep Disorders Centre on five occasions for polysomnography and multiple sleep latency tests: (1) during adaptation; (2) 3 weeks before Ramadan, after having performed Islamic fasting for 1 week (baseline fasting); (3) 1 week before Ramadan (non-fasting baseline); (4) 2 weeks into Ramadan (Ramadan); and (5) 2 weeks after Ramadan (non-fasting; Recovery). Daytime sleepiness was assessed using the Epworth Sleepiness Scale and the multiple sleep latency test. The participants had a mean age of 26.6 ± 4.9 years, a body mass index of 23.7 ± 3.5 kg m(-2) and an Epworth Sleepiness Scale score of 7.3 ± 2.7. There was no change in weight or the Epworth Sleepiness Scale in the four study periods. The rapid eye movement sleep percentage was significantly lower during fasting. There was no difference in sleep latency, non-rapid eye movement sleep percentage, arousal index and sleep efficiency. The multiple sleep latency test analysis revealed no difference in the sleep latency between the 'non-fasting baseline', 'baseline fasting', 'Ramadan' and 'Recovery' time points. Under conditions of a fixed sleep-wake schedule and a fixed caloric intake, Islamic intermittent fasting results in decreased rapid eye movement sleep with no impact on other sleep stages, the arousal index or daytime sleepiness. © 2013 European Sleep Research Society.

Viral marketing as epidemiological model

OpenAIRE

Rodrigues, Helena Sofia; Fonseca, Manuel

2015-01-01

In epidemiology, an epidemic is defined as the spread of an infectious disease to a large number of people in a given population within a short period of time. In the marketing context, a message is viral when it is broadly sent and received by the target market through person-to-person transmission. This specific marketing communication strategy is commonly referred as viral marketing. Due to this similarity between an epidemic and the viral marketing process and because the understanding of...

Ethical Considerations in Research Participation Virality.

Science.gov (United States)

Ellis-Barton, Carol

2016-07-01

This article seeks to commence and encourage discussion around the upcoming ethical challenges of virality in network structures. When the call for participation in a research project on lupus in Ireland went from an advertisement in a newsletter to a meme (unit of transmissible information) on a closed Facebook page, the ethical considerations of virality were raised. The article analyzes the Association of Internet Researchers guidelines, Facebook policies, and the context of privacy in relation to virality. Virality creates the leverage for methodological pluralism. The nature of the inquiry can determine the method rather than the other way around. Viral ethical considerations are evolving due to the cyber world becoming the primary meme of communication, with flexibility in the researcher's protocol providing opportunities for efficient, cost-effective, and diverse recruitment. © The Author(s) 2016.

The N-Terminal of Aquareovirus NS80 Is Required for Interacting with Viral Proteins and Viral Replication.

Directory of Open Access Journals (Sweden)

Jie Zhang

Full Text Available Reovirus replication and assembly occurs within viral inclusion bodies that formed in specific intracellular compartments of cytoplasm in infected cells. Previous study indicated that aquareovirus NS80 is able to form inclusion bodies, and also can retain viral proteins within its inclusions. To better understand how NS80 performed in viral replication and assembly, the functional regions of NS80 associated with other viral proteins in aquareovirus replication were investigated in this study. Deletion mutational analysis and rotavirus NSP5-based protein association platform were used to detect association regions. Immunofluorescence images indicated that different N-terminal regions of NS80 could associate with viral proteins VP1, VP4, VP6 and NS38. Further co-immunoprecipitation analysis confirmed the interaction between VP1, VP4, VP6 or NS38 with different regions covering the N-terminal amino acid (aa, 1-471 of NS80, respectively. Moreover, removal of NS80 N-terminal sequences required for interaction with proteins VP1, VP4, VP6 or NS38 not only prevented the capacity of NS80 to support viral replication in NS80 shRNA-based replication complementation assays, but also inhibited the expression of aquareovirus proteins, suggesting that N-terminal regions of NS80 are necessary for viral replication. These results provided a foundational basis for further understanding the role of NS80 in viral replication and assembly during aquareovirus infection.

Hot News: Impact of Low-level Viremia on Treatment Outcomes During ART - Is it Time to Revise the Definition of Virological Failure?

Science.gov (United States)

Poveda, Eva; Crespo, Manuel

2018-01-01

The level of HIV-RNA in plasma (HIV viral load) is the main marker used to monitor the virological response to antiretroviral therapy (ART) in HIV-infected patients. The threshold used to define virological suppression has historically been dictated by the limits of detection of the commercial assays used to quantify the plasma viral load. Thus, as more sensitive assays have proliferated and become more widely available, the definition has shifted from ART is to maintain virological suppression below 200 cop/mL, or even > 1000 cop/mL according to the WHO guidelines for low-income and middle-income countries. Several studies have evaluated the impact of low-level viremia as intermittent episodes (blips) or persistent detectable low-level viremia (50-1000 cop/mL) on treatment outcomes during ART. Some of these studies have suggested a potential role for low-level viremia as a predictor of virological failure, although up to now the data have been insufficient and controversial to guide clinical management. Hermans et al. have recently published the results of a large (n = 70.930 HIV-infected patients) multicenter study (57 clinical sites in South Africa) with a median follow-up for more than 2 years, to evaluate the incidence and impact of low-level viremia (defined as HIV-RNA viral load of 51-999 cop/mL) and its association with virological failure (Hermans et al., Lancet Infect Dis 2018;18:188-97). This large cohort study concludes that overall, patients with low-level viremia are predisposed to subsequent virological failure. The risk of virological failure was 5 times higher for patients with low-level viremia ranging 400-999 cop/mL, and 2 times higher for those with viremia ranging 51-199 cop/mL, compared with patients maintaining viral load suppression (ART should be recognized and considered in clinical decision-making. Furthermore, current WHO guidelines for low-income and middleincome countries should be revised and updated. Although substantial differences

The influence of continuous and intermittent traffic noise on sleep

Science.gov (United States)

Eberhardt, J. L.; Stråle, L.-O.; Berlin, M. H.

1987-08-01

The effects of road traffic noise on sleep were studied in the laboratory using nine young male adults (aged 20-26). The subjects were exposed to noise with different temporal characteristics: (i) continuous traffic noise of 36 dB(A) or 45 dB(A), (ii) intermittent noise of 50 truck passages with L pmax = 45 dB(A) ( L eq = 29 dB(A)) or L pmax = 55 dB(A) ( L eq = 36 dB(A)), and (iii) a combination of continuous (45 dB(A)) and intermittent ( L pmax = 55 dB(A)) traffic noise. For one noise condition (intermittent 55 dB(A)) the effect of the use of ear plugs was also studied. The intermittent noise of L pmax = 45 dB(A) caused transitions towards lighter sleep, whereas 55 dB(A) was needed to induce awakening effects. It could be shown that the probability for arousal reactions depends on the emergence of the noise peaks from the background, rather than the absolute noise peak level. Continuous traffic noise of 45 dB(A) caused REM sleep deficits, while intermittent traffic noise of L pmax = 45 dB(A) caused stage III+IV deficits. The night with ear plugs was virtually undisturbed. After nights with REM sleep deficits the subjective sleep quality was rated lower and mood was influenced adversely. For the types of exposure used in the present investigation L eq alone is not an adequate descriptor of the noise dose, relating to the sleep disturbances observed. From the present experiment, together with other existing data, it might be concluded that the WHO recommendation of L eq = 35 dB(A) is adequate, but should be supplemented with a maximum noise level, as expressed for example in L pmax or LI, that should not be exceeded.

Effects of chronic pollution and water flow intermittency on stream biofilms biodegradation capacity.

Science.gov (United States)

Rožman, Marko; Acuña, Vicenç; Petrović, Mira

2018-02-01

A mesocosm case study was conducted to gain understanding and practical knowledge on biofilm emerging contaminants biodegradation capacity under stressor and multiple stressor conditions. Two real life scenarios: I) biodegradation in a pristine intermittent stream experiencing acute pollution and II) biodegradation in a chronically polluted intermittent stream, were examined via a multifactorial experiment using an artificial stream facility. Stream biofilms were exposed to different water flow conditions i.e. permanent and intermittent water flow. Venlafaxine, a readily biodegradable pharmaceutical was used as a measure of biodegradation capacity while pollution was simulated by a mixture of four emerging contaminants (erythromycin, sulfisoxazole, diclofenac and imidacloprid in addition to venlafaxine) in environmentally relevant concentrations. Biodegradation kinetics monitored via LC-MS/MS was established, statistically evaluated, and used to link biodegradation with stress events. The results suggest that the effects of intermittent flow do not hinder and may even stimulate pristine biofilm biodegradation capacity. Chronic pollution completely reduced biodegradation in permanent water flow experimental treatments while no change in intermittent streams was observed. A combined effect of water flow conditions and emerging contaminants exposure on biodegradation was found. The decrease in biodegradation due to exposure to emerging contaminants is significantly greater in streams with permanent water flow suggesting that the short and medium term biodegradation capacity in intermittent systems may be preserved or even greater than in perennial streams. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of intermittent feedback control on robustness of human-like postural control system

Science.gov (United States)

Tanabe, Hiroko; Fujii, Keisuke; Suzuki, Yasuyuki; Kouzaki, Motoki

2016-03-01

Humans have to acquire postural robustness to maintain stability against internal and external perturbations. Human standing has been recently modelled using an intermittent feedback control. However, the causality inside of the closed-loop postural control system associated with the neural control strategy is still unknown. Here, we examined the effect of intermittent feedback control on postural robustness and of changes in active/passive components on joint coordinative structure. We implemented computer simulation of a quadruple inverted pendulum that is mechanically close to human tiptoe standing. We simulated three pairs of joint viscoelasticity and three choices of neural control strategies for each joint: intermittent, continuous, or passive control. We examined postural robustness for each parameter set by analysing the region of active feedback gain. We found intermittent control at the hip joint was necessary for model stabilisation and model parameters affected the robustness of the pendulum. Joint sways of the pendulum model were partially smaller than or similar to those of experimental data. In conclusion, intermittent feedback control was necessary for the stabilisation of the quadruple inverted pendulum. Also, postural robustness of human-like multi-link standing would be achieved by both passive joint viscoelasticity and neural joint control strategies.

How Can Viral Dynamics Models Inform Endpoint Measures in Clinical Trials of Therapies for Acute Viral Infections?

Directory of Open Access Journals (Sweden)

Carolin Vegvari

Full Text Available Acute viral infections pose many practical challenges for the accurate assessment of the impact of novel therapies on viral growth and decay. Using the example of influenza A, we illustrate how the measurement of infection-related quantities that determine the dynamics of viral load within the human host, can inform investigators on the course and severity of infection and the efficacy of a novel treatment. We estimated the values of key infection-related quantities that determine the course of natural infection from viral load data, using Markov Chain Monte Carlo methods. The data were placebo group viral load measurements collected during volunteer challenge studies, conducted by Roche, as part of the oseltamivir trials. We calculated the values of the quantities for each patient and the correlations between the quantities, symptom severity and body temperature. The greatest variation among individuals occurred in the viral load peak and area under the viral load curve. Total symptom severity correlated positively with the basic reproductive number. The most sensitive endpoint for therapeutic trials with the goal to cure patients is the duration of infection. We suggest laboratory experiments to obtain more precise estimates of virological quantities that can supplement clinical endpoint measurements.

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

Constrained pattern of viral evolution in acute and early HCV infection limits viral plasticity.

Directory of Open Access Journals (Sweden)

Katja Pfafferott

2011-02-01

Full Text Available Cellular immune responses during acute Hepatitis C virus (HCV and HIV infection are a known correlate of infection outcome. Viral adaptation to these responses via mutation(s within CD8+ T-cell epitopes allows these viruses to subvert host immune control. This study examined HCV evolution in 21 HCV genotype 1-infected subjects to characterise the level of viral adaptation during acute and early HCV infection. Of the total mutations observed 25% were within described CD8+ T-cell epitopes or at viral adaptation sites. Most mutations were maintained into the chronic phase of HCV infection (75%. The lack of reversion of adaptations and high proportion of silent substitutions suggests that HCV has structural and functional limitations that constrain evolution. These results were compared to the pattern of viral evolution observed in 98 subjects during a similar phase in HIV infection from a previous study. In contrast to HCV, evolution during acute HIV infection is marked by high levels of amino acid change relative to silent substitutions, including a higher proportion of adaptations, likely reflecting strong and continued CD8+ T-cell pressure combined with greater plasticity of the virus. Understanding viral escape dynamics for these two viruses is important for effective T cell vaccine design.

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

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.

Obstructive sleep apnea: role of intermittent hypoxia and inflammation.

Science.gov (United States)

May, Anna M; Mehra, Reena

2014-10-01

Obstructive sleep apnea results in intermittent hypoxia via repetitive upper airway obstruction leading to partial or complete upper airway closure, apneas and hypopneas, respectively. Intermittent hypoxia leads to sympathetic nervous system activation and oxidative stress with a resultant systemic inflammatory cascade. The putative mechanism by which obstructive sleep apnea has been linked to numerous pathologic conditions including stoke, cardiovascular disease, hypertension, and metabolic derangements is through these systemic effects. Treatment of obstructive sleep apnea appears to reduce systemic markers of inflammation and ameliorates the adverse sequelae of this disease. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

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.

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.

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

Composeable Chat over Low-Bandwidth Intermittent Communication Links

National Research Council Canada - National Science Library

Wilcox, D. R

2007-01-01

Intermittent low-bandwidth communication environments, such as those encountered in U.S. Navy tactical radio and satellite links, have special requirements that do not pertain to commercial applications...

Study of intermittent bifurcations and chaos in boost PFC converters by nonlinear discrete models

International Nuclear Information System (INIS)

Zhang Hao; Ma Xikui; Xue Bianling; Liu Weizeng

2005-01-01

This paper mainly deals with nonlinear phenomena like intermittent bifurcations and chaos in boost PFC converters under peak-current control mode. Two nonlinear models in the form of discrete maps are derived to describe precisely the nonlinear dynamics of boost PFC converters from two points of view, i.e., low- and high-frequency regimes. Based on the presented discrete models, both the evolution of intermittent behavior and the periodicity of intermittency are investigated in detail from the fast and slow-scale aspects, respectively. Numerical results show that the occurrence of intermittent bifurcations and chaos with half one line period is one of the most distinguished dynamical characteristics. Finally, we make some instructive conclusions, which prove to be helpful in improving the performances of practical circuits

Bile acids for viral hepatitis

DEFF Research Database (Denmark)

Chen, Weikeng; Liu, J; Gluud, C

2007-01-01

Trials have assessed bile acids for patients with viral hepatitis, but no consensus has been reached regarding their usefulness.......Trials have assessed bile acids for patients with viral hepatitis, but no consensus has been reached regarding their usefulness....

Synchronization of Hierarchical Time-Varying Neural Networks Based on Asynchronous and Intermittent Sampled-Data Control.

Science.gov (United States)

Xiong, Wenjun; Patel, Ragini; Cao, Jinde; Zheng, Wei Xing

In this brief, our purpose is to apply asynchronous and intermittent sampled-data control methods to achieve the synchronization of hierarchical time-varying neural networks. The asynchronous and intermittent sampled-data controllers are proposed for two reasons: 1) the controllers may not transmit the control information simultaneously and 2) the controllers cannot always exist at any time . The synchronization is then discussed for a kind of hierarchical time-varying neural networks based on the asynchronous and intermittent sampled-data controllers. Finally, the simulation results are given to illustrate the usefulness of the developed criteria.In this brief, our purpose is to apply asynchronous and intermittent sampled-data control methods to achieve the synchronization of hierarchical time-varying neural networks. The asynchronous and intermittent sampled-data controllers are proposed for two reasons: 1) the controllers may not transmit the control information simultaneously and 2) the controllers cannot always exist at any time . The synchronization is then discussed for a kind of hierarchical time-varying neural networks based on the asynchronous and intermittent sampled-data controllers. Finally, the simulation results are given to illustrate the usefulness of the developed criteria.

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

OpenAIRE

Howell, Anthony; Harvie, Michelle

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...

Effect of Linguizhugan decoction on hyperlipidemia rats with intermittent fasting.

Science.gov (United States)

Yang, Yubin; Qin, Jian; Ke, Bin; Zhang, Junjie; Shi, Lanying; Li, Qiong

2013-04-01

To explore the effect of Linguizhugan decoction on hyperlipidemia rats with caloric restriction. The hyperlipidemia model of rat was induced by high fat diet for 8 weeks. After the model was established, 26 rats were randomly divided into 4 groups: the control group (n = 6), the model group (n = 6), the intermittent fasting (IF) group (n = 8), and the IF and herbal medicine (IFH) group (n = 6). IF group was applied intermittent fasting every other day. The IFH group was given Linguizhugan decoction every day and intermittent fasting every other day. Blood samples were taken at the end of 16 weeks, and serum ghrelin and lipid was tested. Serum ghrelin in the IF group significantly increased (P < 0.01). Serum ghrelin in IFH group was lower than the IF group (P < 0.05), but higher than the model group (P < 0.01). Linguizhugan decoction may play a part in regulation of energy and appetite in hyperlipidemia rats with IF.

Water quality effects of intermittent water supply in Arraiján, Panama.

Science.gov (United States)

Erickson, John J; Smith, Charlotte D; Goodridge, Amador; Nelson, Kara L

2017-05-01

Intermittent drinking water supply is common in low- and middle-income countries throughout the world and can cause water quality to degrade in the distribution system. In this study, we characterized water quality in one study zone with continuous supply and three zones with intermittent supply in the drinking water distribution network in Arraiján, Panama. Low or zero pressures occurred in all zones, and negative pressures occurred in the continuous zone and two of the intermittent zones. Despite hydraulic conditions that created risks for backflow and contaminant intrusion, only four of 423 (0.9%) grab samples collected at random times were positive for total coliform bacteria and only one was positive for E. coli. Only nine of 496 (1.8%) samples had turbidity >1.0 NTU and all samples had ≥0.2 mg/L free chlorine residual. In contrast, water quality was often degraded during the first-flush period (when supply first returned after an outage). Still, routine and first-flush water quality under intermittent supply was much better in Arraiján than that reported in a previous study conducted in India. Better water quality in Arraiján could be due to better water quality leaving the treatment plant, shorter supply outages, higher supply pressures, a more consistent and higher chlorine residual, and fewer contaminant sources near pipes. The results illustrate that intermittent supply and its effects on water quality can vary greatly between and within distribution networks. The study also demonstrated that monitoring techniques designed specifically for intermittent supply, such as continuous pressure monitoring and sampling the first flush, can detect water quality threats and degradation that would not likely be detected with conventional monitoring. Copyright © 2017 Elsevier Ltd. All rights reserved.

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...

Viral Hepatitis: A through E and Beyond

Science.gov (United States)

... National Digestive Diseases Information Clearinghouse What is viral hepatitis? Viral hepatitis is inflammation of the liver caused by ... and serious. Drugs are available to treat chronic hepatitis. 4 Viral Hepatitis: A through E and Beyond What else ...

Investigation of intermittency in simulated and experimental turbulence data by wavelet analysis

International Nuclear Information System (INIS)

Mahdizadeh, N.; Ramisch, M.; Stroth, U.; Lechte, C.; Scott, B.D.

2004-01-01

Turbulent transport in magnetized plasmas has an intermittent nature. Peaked probability density functions and a 1/frequency decay of the power spectra have been interpreted as signs of self-organized criticality generated, similar to a sand pile, by the critical gradients of ion- (ITG) or electron-temperature-gradient (ETG) driven instabilities. In order to investigate the degree of intermittency in toroidally confined plasmas in the absence of critical pressure or temperature gradients, data from the drift-Alfven-wave turbulence code DALF3 [B. Scott, Plasma Phys. Controlled Fusion 39, 1635 (1997)], running with a fixed background pressure gradient, and from a weakly driven low-temperature plasma are analyzed. The intermittency is studied on different temporal scales, which are separated by a wavelet transform. Simulated and experimental data reproduce the results on intermittent transport found in fusion plasmas. It can therefore be expected that in fusion plasmas, too, a substantial fraction of the bursty nature of turbulent transport is not related to avalanches caused by a critical gradient as generated by ITG or ETG turbulence

Viral Hepatitis: Information for Gay and Bisexual Men

Science.gov (United States)

VIRAL HEPATITIS Information for Gay and Bisexual Men What is viral hepatitis? Viral hepatitis is an infection of the liver caused by one of several ... each virus is spread in different ways. Are gay and bisexual men at risk for viral hepatitis? ...

Mouse Intermittent Hypoxia Mimicking Apnea of Prematurity: Effects on Myelinogenesis and Axonal Maturation

Science.gov (United States)

CAI, JUN; TUONG, CHI MINH; ZHANG, YIPING; SHIELDS, CHRISTOPHER B.; GUO, GANG; FU, HUI; GOZAL, DAVID

2014-01-01

Premature babies are at high risk for both infantile apnea and long-term neurobehavioral deficits. Recent studies suggest that diffuse structural changes in brain white matter are a positive predictor of poor cognitive outcomes. Since oligodendrocyte maturation, myelination, axon development and synapse formation mainly occur in the 3rd trimester of gestation and 1st postnatal year, infantile apnea could lead to and/or exaggerate white matter impairments in preterm neonates. Therefore, we investigated oligodendroglia and axon development in a neonatal mouse model of intermittent hypoxia between postnatal days 2 to 10. During critical phases of central nervous system development, intermittent hypoxia induced hypomyelination in the corpus callosum, striatum, fornix and cerebellum, but not the pons or spinal cord. Intermittent hypoxia-elicited alterations in myelin-forming processes were reflected by decreased expression of myelin proteins, including MBP, PLP, MAG and CNPase, possibly due to arrested maturation of oligodendrocytes. Ultra-structural abnormalities were apparent in the myelin sheath and axon. Immature oligodendrocytes were more vulnerable to neonatal intermittent hypoxia exposures than developing axons, suggesting that hypomyelination may contribute, at least partially, to axonal deficits. Insufficient neurofilament synthesis with anomalous components of neurofilament subunits, β-tubulin and MAP2 isoforms indicated immaturity of axons in intermittent hypoxia-exposed mouse brains. In addition, down-regulation of Synapsin I, Synaptophysin and Gap-43 phosphorylation suggested a potential stunt in axonogenesis and synaptogenesis. The region-selective and complex impairment in brain white matter induced by intermittent hypoxia was further associated with electrophysiological changes that may underlie long-term neurobehavioral sequelae. PMID:21953180

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

Contagious Content: Viral Video Ads Identification of Content Characteristics that Help Online Video Advertisements Go Viral

Directory of Open Access Journals (Sweden)

Yentl Knossenburg

2016-12-01

Full Text Available Why do some online video advertisements go viral while others remain unnoticed? What kind of video content keeps the viewer interested and motivated to share? Many companies have realized the need to innovate their marketing strategies and have embraced the newest ways of using technology, as the Internet, to their advantage as in the example of virality. Yet few marketers actually understand how, and academic literature on this topic is still in development. This study investigated which content characteristics distinguish successful from non-successful online viral video advertisements by analyzing 641 cases using Structural Equation Modeling. Results show that Engagement and Surprise are two main content characteristics that significantly increase the chance of online video advertisements to go viral.  

Accelerated magnetic resonance diffusion tensor imaging of the median nerve using simultaneous multi-slice echo planar imaging with blipped CAIPIRINHA.

Science.gov (United States)

Filli, Lukas; Piccirelli, Marco; Kenkel, David; Boss, Andreas; Manoliu, Andrei; Andreisek, Gustav; Bhat, Himanshu; Runge, Val M; Guggenberger, Roman

2016-06-01

To investigate the feasibility of MR diffusion tensor imaging (DTI) of the median nerve using simultaneous multi-slice echo planar imaging (EPI) with blipped CAIPIRINHA. After federal ethics board approval, MR imaging of the median nerves of eight healthy volunteers (mean age, 29.4 years; range, 25-32) was performed at 3 T using a 16-channel hand/wrist coil. An EPI sequence (b-value, 1,000 s/mm(2); 20 gradient directions) was acquired without acceleration as well as with twofold and threefold slice acceleration. Fractional anisotropy (FA), mean diffusivity (MD) and quality of nerve tractography (number of tracks, average track length, track homogeneity, anatomical accuracy) were compared between the acquisitions using multivariate ANOVA and the Kruskal-Wallis test. Acquisition time was 6:08 min for standard DTI, 3:38 min for twofold and 2:31 min for threefold acceleration. No differences were found regarding FA (standard DTI: 0.620 ± 0.058; twofold acceleration: 0.642 ± 0.058; threefold acceleration: 0.644 ± 0.061; p ≥ 0.217) and MD (standard DTI: 1.076 ± 0.080 mm(2)/s; twofold acceleration: 1.016 ± 0.123 mm(2)/s; threefold acceleration: 0.979 ± 0.153 mm(2)/s; p ≥ 0.074). Twofold acceleration yielded similar tractography quality compared to standard DTI (p > 0.05). With threefold acceleration, however, average track length and track homogeneity decreased (p = 0.004-0.021). Accelerated DTI of the median nerve is feasible. Twofold acceleration yields similar results to standard DTI. • Standard DTI of the median nerve is limited by its long acquisition time. • Simultaneous multi-slice acquisition is a new technique for accelerated DTI. • Accelerated DTI of the median nerve yields similar results to standard DTI.

Cardiovascular disease in obstructive sleep apnoea syndrome: the role of intermittent hypoxia and inflammation.

LENUS (Irish Health Repository)

Garvey, J F

2012-02-01

There is increasing evidence that intermittent hypoxia plays a role in the development of cardiovascular risk in obstructive sleep apnoea syndrome (OSAS) through the activation of inflammatory pathways. The development of translational models of intermittent hypoxia has allowed investigation of its role in the activation of inflammatory mechanisms and promotion of cardiovascular disease in OSAS. There are noticeable differences in the response to intermittent hypoxia between body tissues but the hypoxia-sensitive transcription factors hypoxia-inducible factor-1 and nuclear factor-kappaB appear to play a key role in mediating the inflammatory and cardiovascular consequences of OSAS. Expanding our understanding of these pathways, the cross-talk between them and the activation of inflammatory mechanisms by intermittent hypoxia in OSAS will provide new avenues of therapeutic opportunity for the disease.

Metabolic syndrome in patients with prostate cancer undergoing intermittent androgen-deprivation therapy.

Science.gov (United States)

Rezaei, Mohammadali Mohammadzadeh; Rezaei, Mohammadhadi Mohammadzadeh; Ghoreifi, Alireza; Kerigh, Behzad Feyzzadeh

2016-01-01

The presence of metabolic syndrome in men with prostate cancer (PCa) undergoing androgen-deprivation therapy (ADT), especially intermittent type, has not been completely evaluated. The aim of this study is to evaluate metabolic syndrome in men with PCa undergoing intermittent ADT. In this longitudinal study, we studied the prevalence of metabolic syndrome and its components in 190 patients who were undergoing intermittent ADT. The metabolic syndrome was defined according to the Adult Treatment Panel III criteria. All metabolic parameters, including lipid profile, blood glucose, blood pressures, and waist circumferences of the patients were measured six and 12 months after treatment. Mean age of the patients was 67.5 ± 6.74 years. The incidence of metabolic syndrome after six and 12 months was 6.8% and 14.7%, respectively. Analysis of various components of the metabolic syndrome revealed that patients had significantly higher overall prevalence of hyperglycemia, abdominal obesity, and hypertriglyceridemia in their six- and 12-month followups, but blood pressure has not been changed in the same period except for diastolic blood pressure after six months. Although there was an increased risk of metabolic syndrome in patients receiving intermittent ADT, it was lower than other studies that treated the same patients with continuous ADT. Also it seems that intermittent ADT has less metabolic complications than continuous ADT and could be used as a safe alternative in patients with advanced and metastatic PCa.

Coherent and intermittent ensemble oscillations emerge from networks of irregular spiking neurons.

Science.gov (United States)

Hoseini, Mahmood S; Wessel, Ralf

2016-01-01

Local field potential (LFP) recordings from spatially distant cortical circuits reveal episodes of coherent gamma oscillations that are intermittent, and of variable peak frequency and duration. Concurrently, single neuron spiking remains largely irregular and of low rate. The underlying potential mechanisms of this emergent network activity have long been debated. Here we reproduce such intermittent ensemble oscillations in a model network, consisting of excitatory and inhibitory model neurons with the characteristics of regular-spiking (RS) pyramidal neurons, and fast-spiking (FS) and low-threshold spiking (LTS) interneurons. We find that fluctuations in the external inputs trigger reciprocally connected and irregularly spiking RS and FS neurons in episodes of ensemble oscillations, which are terminated by the recruitment of the LTS population with concurrent accumulation of inhibitory conductance in both RS and FS neurons. The model qualitatively reproduces experimentally observed phase drift, oscillation episode duration distributions, variation in the peak frequency, and the concurrent irregular single-neuron spiking at low rate. Furthermore, consistent with previous experimental studies using optogenetic manipulation, periodic activation of FS, but not RS, model neurons causes enhancement of gamma oscillations. In addition, increasing the coupling between two model networks from low to high reveals a transition from independent intermittent oscillations to coherent intermittent oscillations. In conclusion, the model network suggests biologically plausible mechanisms for the generation of episodes of coherent intermittent ensemble oscillations with irregular spiking neurons in cortical circuits. Copyright © 2016 the American Physiological Society.

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)

Determining order-up-to levels under periodic review for compound binomial (intermittent) demand

NARCIS (Netherlands)

Teunter, R. H.; Syntetos, A. A.; Babai, M. Z.

2010-01-01

We propose a new method for determining order-up-to levels for intermittent demand items in a periodic review system. Contrary to existing methods, we exploit the intermittent character of demand by modelling lead time demand as a compound binomial process. in an extensive numerical study using

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

Intermittent fasting decreases oxidative stress parameters in Wistar rats (Rattus norvegicus)

OpenAIRE

Titis Nurmasitoh; Shindy Yudha Utami; Endah Kusumawardani; Abdulhalim Ahmad Najmuddin; Ika Fidianingsih

2018-01-01

Background Chronic and degenerative diseases are closely related to modern lifestyles that tend to be deficient in physical activity but excessive in food intake. One method used to overcome this problem is dietary restriction through intermittent fasting. Intermittent fasting decreases the risk of chronic and degenerative diseases, e.g. by lowering oxidative stress. Oxidative stress can be determined from the malondialdehyde (MDA) levels and lipid profile in the blood. The present study a...

Kinetics of viral shedding provide insights into the epidemiology of viral hemorrhagic septicemia in Pacific herring

Science.gov (United States)

Hershberger, Paul K.; Gregg, Jacob L.; Winton, James R.; Grady, Courtney; Collins, Rachael

2010-01-01

Losses from infectious diseases are an important component of natural mortality among marine fish species, but factors controlling the ecology of these diseases and their potential responses to anthropogenic changes are poorly understood. We used viral hemorrhagic septicemia virus (VHSV) and a laboratory stock of Pacific herring Clupea pallasii to investigate the kinetics of viral shedding and its effect on disease transmission and host mortality. Outbreaks of acute disease, accompanied by mortality and viral shedding, were initiated after waterborne exposure of herring to concentrations of VHSV as low as 101 plaque-forming units (pfu) ml–1. Shed virus in flow-through tanks was first detected 4 to 5 d post-exposure, peaked after 6 to 10 d, and was no longer detected after 16 d. Shedding rates, calculated from density, flow and waterborne virus titer reached 1.8 to 5.0 × 108 pfu fish–1 d–1. Onset of viral shedding was dose-dependent and preceded initial mortality by 2 d. At 21 d, cumulative mortality in treatment groups ranged from 81 to 100% and was dependent not on challenge dose, but on the kinetics and level of viral shedding by infected fish in the tank. Possible consequences of the viral shedding and disease kinetics are discussed in the context of epizootic initiation and perpetuation among populations of wild Pacific herring.

Clean intermittent self-catheterisation - principles and practice

Directory of Open Access Journals (Sweden)

Arun Narayanaswamy

2000-01-01

Full Text Available This review of the literature on the principles and prac-tice of clean intermittent self-catheterisation includes the role of antiseptics/antibiotics, and outcome. It covers ac-ceptance of the technique, urinary tract infection, conti-nence, and preservation of upper urinary tract.

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)

The two normalization schemes of factorial moments in high energy collisions and the dependence intermittency degree on average transverse momentum

International Nuclear Information System (INIS)

Wu Yuanfnag; Liu Lianshou

1992-01-01

The two different normalization scheme of factorial moments are analyzed carefully. It is found that in both the cases of fixed multiplicity and of intermittency independent of multiplicity, the intermittency indexes obtained from these two normalization schemes are equal to each other. In the case of non-fixed multiplicity and intermittency depending on multiplicity, the formulae expressing the intermittency indexes from the two different normalization schemes in terms of the dynamical index are given. The experimentally observed dependency of intermittency degree on transverse momentum cut is fully recovered by means of the assumption that intermittency degree depends on average transverse momentum per event. It confirms importance of the dependency of intermittency on average momentum

77 FR 67743 - Federal Employees Health Benefits Program Coverage for Certain Intermittent Employees

Science.gov (United States)

2012-11-14

... employees who work on intermittent schedules eligible to be enrolled in a health benefits plan under the... put their health and safety at risk in order to assist those who have been affected by the storm... health insurance coverage based on the potentially diverse work schedules of intermittent employees...

Affecting Factors and Outcome on Intermittent Internet Pulling Behavior in Taiwan's Undergraduate Students

Science.gov (United States)

Yang, Hui-Jen; Lay, Yun-Long

2011-01-01

Nowadays people's lives heavily rely on Internet facilities. Internet users generally have constant Internet connectivity and intermittently click on sites they want to access even amidst studying or working. In this study, we sought to examine the factors affecting intermittent Internet pulling behavior on undergraduate students. Furthermore, the…

Virus del dengue: estructura y ciclo viral Dengue virus: structure and viral cycle

Directory of Open Access Journals (Sweden)

Myriam L Velandia

2011-03-01

Full Text Available El virus del dengue (DENV es el agente causal de la enfermedad conocida como dengue, que es la principal enfermedad viral transmitida por artrópodos en el mundo. El DENV es un flavivirus que ingresa por endocitosis y se replica en el citoplasma de la célula infectada, originando tres proteínas estructurales y siete proteínas no estructurales, sobre las cuales se conocen sólo algunas de sus funciones en la replicación viral o en la infección. El ciclo viral que ocurre en las células infectadas hasta ahora está comenzando a aclararse y su conocimiento permitirá en el futuro próximo diseñar racionalmente moléculas que lo intervengan y eviten la replicación del virus. Durante la infección, el individuo puede presentar fiebre indiferenciada o, en otros casos, puede presentar un proceso generalizado de activación de la respuesta inmunitaria innata y adquirida, lo cual provoca la liberación de factores inflamatorios solubles que alteran la fisiología de los tejidos, principalmente el endotelio, conllevando al desarrollo de manifestaciones clínicas graves. Aunque se ha identificado un gran número de factores del individuo asociados al desarrollo de la enfermedad por DENV, queda por identificar el papel de las diferentes proteínas virales en la patogenia de la enfermedad. En la presente revisión, se presenta una breve actualización sobre la estructura y biología del DENV, de su ciclo viral intracelular y, finalmente, se introducen algunos conceptos sobre la inmunopatogenia de la enfermedad producida por este agente.Dengue virus (DENV is responsible for the clinical entity known as dengue that is a great concern for economy and public health of tropical countries. This flavivirus is a single strand RNA virus that after their translation and replication in host cells produces three structural and seven non-structural proteins with specific function in replication or cell binding process that we will describe here. Intracellular

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.

Chronic intermittent hypoxia induces cardiac inflammation and dysfunction in a rat obstructive sleep apnea model.

Science.gov (United States)

Wei, Qin; Bian, Yeping; Yu, Fuchao; Zhang, Qiang; Zhang, Guanghao; Li, Yang; Song, Songsong; Ren, Xiaomei; Tong, Jiayi

2016-11-01

Chronic intermittent hypoxia is considered to play an important role in cardiovascular pathogenesis during the development of obstructive sleep apnea (OSA). We used a well-described OSA rat model induced with simultaneous intermittent hypoxia. Male Sprague Dawley rats were individually placed into plexiglass chambers with air pressure and components were electronically controlled. The rats were exposed to intermittent hypoxia 8 hours daily for 5 weeks. The changes of cardiac structure and function were examined by ultrasound. The cardiac pathology, apoptosis, and fibrosis were analyzed by H&E staining, TUNNEL assay, and picosirius staining, respectively. The expression of inflammation and fibrosis marker genes was analyzed by quantitative real-time PCR and Western blot. Chronic intermittent hypoxia/low pressure resulted in significant increase of left ventricular internal diameters (LVIDs), end-systolic volume (ESV), end-diastolic volume (EDV), and blood lactate level and marked reduction in ejection fraction and fractional shortening. Chronic intermittent hypoxia increased TUNNEL-positive myocytes, disrupted normal arrangement of cardiac fibers, and increased Sirius stained collagen fibers. The expression levels of hypoxia induced factor (HIF)-1α, NF-kB, IL-6, and matrix metallopeptidase 2 (MMP-2) were significantly increased in the heart of rats exposed to chronic intermittent hypoxia. In conclusion, the left ventricular function was adversely affected by chronic intermittent hypoxia, which is associated with increased expression of HIF-1α and NF-kB signaling molecules and development of cardiac inflammation, apoptosis and fibrosis. © 2016 by the Journal of Biomedical Research. All rights reserved.

APOBEC3 Interference during Replication of Viral Genomes

Directory of Open Access Journals (Sweden)

Luc Willems

2015-06-01

Full Text Available Co-evolution of viruses and their hosts has reached a fragile and dynamic equilibrium that allows viral persistence, replication and transmission. In response, infected hosts have developed strategies of defense that counteract the deleterious effects of viral infections. In particular, single-strand DNA editing by Apolipoprotein B Editing Catalytic subunits proteins 3 (APOBEC3s is a well-conserved mechanism of mammalian innate immunity that mutates and inactivates viral genomes. In this review, we describe the mechanisms of APOBEC3 editing during viral replication, the viral strategies that prevent APOBEC3 activity and the consequences of APOBEC3 modulation on viral fitness and host genome integrity. Understanding the mechanisms involved reveals new prospects for therapeutic intervention.

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.

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

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 ...

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

Mobilization of microspheres from a fractured soil during intermittent infiltration events

Science.gov (United States)

Mohanty, Sanjay; Bulicek, Mark; Metge, David W.; Harvey, Ronald W.; Ryan, Joseph N.; Boehm, Alexandria B.

2015-01-01

Pathogens or biocolloids mobilized in the vadose zone may consequently contaminate groundwater. We found that microspheres were mobilized from a fractured soil during intermittent rainfall and the mobilization was greater when the microsphere size was larger and when the soil had greater water permeability.The vadose zone filters pathogenic microbes from infiltrating water and consequently protects the groundwater from possible contamination. In some cases, however, the deposited microbes may be mobilized during rainfall and migrate into the groundwater. We examined the mobilization of microspheres, surrogates for microbes, in an intact core of a fractured soil by intermittent simulated rainfall. Fluorescent polystyrene microspheres of two sizes (0.5 and 1.8 mm) and Br− were first applied to the core to deposit the microspheres, and then the core was subjected to three intermittent infiltration events to mobilize the deposited microspheres. Collecting effluent samples through a 19-port sampler at the base of the core, we found that water flowed through only five ports, and the flow rates varied among the ports by a factor of 12. These results suggest that flow paths leading to the ports had different permeabilities, partly due to macropores. Although 40 to 69% of injected microspheres were retained in the core during their application, 12 to 30% of the retained microspheres were mobilized during three intermittent infiltration events. The extent of microsphere mobilization was greater in flow paths with greater permeability, which indicates that macropores could enhance colloid mobilization during intermittent infiltration events. In all ports, the 1.8-mm microspheres were mobilized to a greater extent than the 0.5-mm microspheres, suggesting that larger colloids are more likely to mobilize. These results are useful in assessing the potential of pathogen mobilization and colloid-facilitated transport of contaminants in the subsurface under natural infiltration

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.

Effects of intermittent fasting on body composition and clinical health markers in humans.

Science.gov (United States)

Tinsley, Grant M; La Bounty, Paul M

2015-10-01

Intermittent fasting is a broad term that encompasses a variety of programs that manipulate the timing of eating occasions by utilizing short-term fasts in order to improve body composition and overall health. This review examines studies conducted on intermittent fasting programs to determine if they are effective at improving body composition and clinical health markers associated with disease. Intermittent fasting protocols can be grouped into alternate-day fasting, whole-day fasting, and time-restricted feeding. Alternate-day fasting trials of 3 to 12 weeks in duration appear to be effective at reducing body weight (≈3%-7%), body fat (≈3-5.5 kg), total cholesterol (≈10%-21%), and triglycerides (≈14%-42%) in normal-weight, overweight, and obese humans. Whole-day fasting trials lasting 12 to 24 weeks also reduce body weight (≈3%-9%) and body fat, and favorably improve blood lipids (≈5%-20% reduction in total cholesterol and ≈17%-50% reduction in triglycerides). Research on time-restricted feeding is limited, and clear conclusions cannot be made at present. Future studies should examine long-term effects of intermittent fasting and the potential synergistic effects of combining intermittent fasting with exercise. © The Author(s) 2015. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

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.

Tangent map intermittency as an approximate analysis of intermittency in a high dimensional fully stochastic dynamical system: The Tangled Nature model.

Science.gov (United States)

Diaz-Ruelas, Alvaro; Jeldtoft Jensen, Henrik; Piovani, Duccio; Robledo, Alberto

2016-12-01

It is well known that low-dimensional nonlinear deterministic maps close to a tangent bifurcation exhibit intermittency and this circumstance has been exploited, e.g., by Procaccia and Schuster [Phys. Rev. A 28, 1210 (1983)], to develop a general theory of 1/f spectra. This suggests it is interesting to study the extent to which the behavior of a high-dimensional stochastic system can be described by such tangent maps. The Tangled Nature (TaNa) Model of evolutionary ecology is an ideal candidate for such a study, a significant model as it is capable of reproducing a broad range of the phenomenology of macroevolution and ecosystems. The TaNa model exhibits strong intermittency reminiscent of punctuated equilibrium and, like the fossil record of mass extinction, the intermittency in the model is found to be non-stationary, a feature typical of many complex systems. We derive a mean-field version for the evolution of the likelihood function controlling the reproduction of species and find a local map close to tangency. This mean-field map, by our own local approximation, is able to describe qualitatively only one episode of the intermittent dynamics of the full TaNa model. To complement this result, we construct a complete nonlinear dynamical system model consisting of successive tangent bifurcations that generates time evolution patterns resembling those of the full TaNa model in macroscopic scales. The switch from one tangent bifurcation to the next in the sequences produced in this model is stochastic in nature, based on criteria obtained from the local mean-field approximation, and capable of imitating the changing set of types of species and total population in the TaNa model. The model combines full deterministic dynamics with instantaneous parameter random jumps at stochastically drawn times. In spite of the limitations of our approach, which entails a drastic collapse of degrees of freedom, the description of a high-dimensional model system in terms of a low

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.

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...

Turbulent intermittent structure in non-homogeneous non-local flows

Science.gov (United States)

Mahjoub, O. B.; Castilla, R.; Vindel, J. M.; Redondo, J. M.

2010-05-01

Data from SABLES98 experimental campaign have been used in order to study the influence of stability (from weak to strong stratification) on intermittency [1]. Standard instrumentation, 14 thermocouples and 3 sonic anemometers at three levels (5.8, 13.5 and 32 m) were available in September 1998 and calculations are done in order to evaluate structure functions and the scale to scale characteristics. Using BDF [2-4] as well as other models of cascades, the spectral equilibrium values were used to calculate fluxes of momentum and heat as well as non-homogeneous models and the turbulent mixing produced. The differences in structure and higher order moments between stable, convective and neutral turbulence were used to identify differences in turbulent intermittent mixing and velocity PDF's. The intermittency of atmospheric turbulence in strongly stable situations affected by buoyancy and internal waves are seen to modify the structure functions exponents and intermittency, depending on the modulus of the Richardson's number,Ri, as well as of the Monin-Obukhov and Ozmidov lengthscales. The topological aspects of the turbulence affected by stratification reduce the vertical length-scales to a maximum described by the Thorpe and the Ozmidov lenth-scales, but intermittency, Kurtosis and other higher order descriptors of the turbulence based on spectral wavelet analysis are also affected in a complex way [5,6]. The relationship between stratification, intermittency, µ(Ri) and the fractal dimension of the stable flows and between the dispersion, the fractal dimension are discussed. The data analyzed is from the campaign SABLES-98 at the north-west Iberian Peninsula plateau.(Cuxart et al. 2000). Conditional statistics of the relationship between µ(Ri) are confirmed as in (Vindel et al 2008)[4] and compared with laboratory experiments and with 2D-3D aspects of the turbulence cascade. The use of BDF [3] model comparing the corresponding relative scaling exponents which are

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.

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.)

The Pacific Ocean virome (POV: a marine viral metagenomic dataset and associated protein clusters for quantitative viral ecology.

Directory of Open Access Journals (Sweden)

Bonnie L Hurwitz

Full Text Available Bacteria and their viruses (phage are fundamental drivers of many ecosystem processes including global biogeochemistry and horizontal gene transfer. While databases and resources for studying function in uncultured bacterial communities are relatively advanced, many fewer exist for their viral counterparts. The issue is largely technical in that the majority (often 90% of viral sequences are functionally 'unknown' making viruses a virtually untapped resource of functional and physiological information. Here, we provide a community resource that organizes this unknown sequence space into 27 K high confidence protein clusters using 32 viral metagenomes from four biogeographic regions in the Pacific Ocean that vary by season, depth, and proximity to land, and include some of the first deep pelagic ocean viral metagenomes. These protein clusters more than double currently available viral protein clusters, including those from environmental datasets. Further, a protein cluster guided analysis of functional diversity revealed that richness decreased (i from deep to surface waters, (ii from winter to summer, (iii and with distance from shore in surface waters only. These data provide a framework from which to draw on for future metadata-enabled functional inquiries of the vast viral unknown.

The Pacific Ocean virome (POV): a marine viral metagenomic dataset and associated protein clusters for quantitative viral ecology.

Science.gov (United States)

Hurwitz, Bonnie L; Sullivan, Matthew B

2013-01-01

Bacteria and their viruses (phage) are fundamental drivers of many ecosystem processes including global biogeochemistry and horizontal gene transfer. While databases and resources for studying function in uncultured bacterial communities are relatively advanced, many fewer exist for their viral counterparts. The issue is largely technical in that the majority (often 90%) of viral sequences are functionally 'unknown' making viruses a virtually untapped resource of functional and physiological information. Here, we provide a community resource that organizes this unknown sequence space into 27 K high confidence protein clusters using 32 viral metagenomes from four biogeographic regions in the Pacific Ocean that vary by season, depth, and proximity to land, and include some of the first deep pelagic ocean viral metagenomes. These protein clusters more than double currently available viral protein clusters, including those from environmental datasets. Further, a protein cluster guided analysis of functional diversity revealed that richness decreased (i) from deep to surface waters, (ii) from winter to summer, (iii) and with distance from shore in surface waters only. These data provide a framework from which to draw on for future metadata-enabled functional inquiries of the vast viral unknown.

Viral-specific T-cell transfer from HSCT donor for the treatment of viral infections or diseases after HSCT.

Science.gov (United States)

Qian, C; Wang, Y; Reppel, L; D'aveni, M; Campidelli, A; Decot, V; Bensoussan, D

2018-02-01

Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative option for treatment of some malignant and non-malignant hematological diseases. However, post-HSCT patients are severely immunocompromised and susceptible to viral infections, which are a major cause of morbidity and mortality. Although antiviral agents are now available for most types of viral infections, they are not devoid of side effects and their efficacy is limited when there is no concomitant antiviral immune reconstitution. In recent decades, adoptive transfer of viral-specific T cells (VSTs) became an alternative treatment for viral infection after HSCT. However, two major issues are concerned in VST transfer: the risk of GVHD and antiviral efficacy. We report an exhaustive review of the published studies that focus on prophylactic and/or curative therapy by donor VST transfer for post-HSCT common viral infections. A low incidence of GVHD and a good antiviral efficacy was observed after adoptive transfer of VSTs from HSCT donor. Viral-specific T-cell transfer is a promising approach for a broad clinical application. Nevertheless, a randomized controlled study in a large cohort of patients comparing antiviral treatment alone to antiviral treatment combined with VSTs is still needed to demonstrate efficacy and safety.

Viral membrane fusion

International Nuclear Information System (INIS)

Harrison, Stephen C.

2015-01-01

Membrane fusion is an essential step when enveloped viruses enter cells. Lipid bilayer fusion requires catalysis to overcome a high kinetic barrier; viral fusion proteins are the agents that fulfill this catalytic function. Despite a variety of molecular architectures, these proteins facilitate fusion by essentially the same generic mechanism. Stimulated by a signal associated with arrival at the cell to be infected (e.g., receptor or co-receptor binding, proton binding in an endosome), they undergo a series of conformational changes. A hydrophobic segment (a “fusion loop” or “fusion peptide”) engages the target-cell membrane and collapse of the bridging intermediate thus formed draws the two membranes (virus and cell) together. We know of three structural classes for viral fusion proteins. Structures for both pre- and postfusion conformations of illustrate the beginning and end points of a process that can be probed by single-virion measurements of fusion kinetics. - Highlights: • Viral fusion proteins overcome the high energy barrier to lipid bilayer merger. • Different molecular structures but the same catalytic mechanism. • Review describes properties of three known fusion-protein structural classes. • Single-virion fusion experiments elucidate mechanism

Viral membrane fusion

Energy Technology Data Exchange (ETDEWEB)

Harrison, Stephen C., E-mail: harrison@crystal.harvard.edu

2015-05-15

Membrane fusion is an essential step when enveloped viruses enter cells. Lipid bilayer fusion requires catalysis to overcome a high kinetic barrier; viral fusion proteins are the agents that fulfill this catalytic function. Despite a variety of molecular architectures, these proteins facilitate fusion by essentially the same generic mechanism. Stimulated by a signal associated with arrival at the cell to be infected (e.g., receptor or co-receptor binding, proton binding in an endosome), they undergo a series of conformational changes. A hydrophobic segment (a “fusion loop” or “fusion peptide”) engages the target-cell membrane and collapse of the bridging intermediate thus formed draws the two membranes (virus and cell) together. We know of three structural classes for viral fusion proteins. Structures for both pre- and postfusion conformations of illustrate the beginning and end points of a process that can be probed by single-virion measurements of fusion kinetics. - Highlights: • Viral fusion proteins overcome the high energy barrier to lipid bilayer merger. • Different molecular structures but the same catalytic mechanism. • Review describes properties of three known fusion-protein structural classes. • Single-virion fusion experiments elucidate mechanism.

THE EFFECT OF INTERMITTENT GYRO-SCALE SLAB TURBULENCE ON PARALLEL AND PERPENDICULAR COSMIC-RAY TRANSPORT

International Nuclear Information System (INIS)

Le Roux, J. A.

2011-01-01

Earlier work based on nonlinear guiding center (NLGC) theory suggested that perpendicular cosmic-ray transport is diffusive when cosmic rays encounter random three-dimensional magnetohydrodynamic turbulence dominated by uniform two-dimensional (2D) turbulence with a minor uniform slab turbulence component. In this approach large-scale perpendicular cosmic-ray transport is due to cosmic rays microscopically diffusing along the meandering magnetic field dominated by 2D turbulence because of gyroresonant interactions with slab turbulence. However, turbulence in the solar wind is intermittent and it has been suggested that intermittent turbulence might be responsible for the observation of 'dropout' events in solar energetic particle fluxes on small scales. In a previous paper le Roux et al. suggested, using NLGC theory as a basis, that if gyro-scale slab turbulence is intermittent, large-scale perpendicular cosmic-ray transport in weak uniform 2D turbulence will be superdiffusive or subdiffusive depending on the statistical characteristics of the intermittent slab turbulence. In this paper we expand and refine our previous work further by investigating how both parallel and perpendicular transport are affected by intermittent slab turbulence for weak as well as strong uniform 2D turbulence. The main new finding is that both parallel and perpendicular transport are the net effect of an interplay between diffusive and nondiffusive (superdiffusive or subdiffusive) transport effects as a consequence of this intermittency.

Intermittent fasting preserves beta-cell mass in obesity-induced diabetes via the autophagy-lysosome pathway.

Science.gov (United States)

Liu, Haiyan; Javaheri, Ali; Godar, Rebecca J; Murphy, John; Ma, Xiucui; Rohatgi, Nidhi; Mahadevan, Jana; Hyrc, Krzysztof; Saftig, Paul; Marshall, Connie; McDaniel, Michael L; Remedi, Maria S; Razani, Babak; Urano, Fumihiko; Diwan, Abhinav

2017-01-01

Obesity-induced diabetes is characterized by hyperglycemia, insulin resistance, and progressive beta cell failure. In islets of mice with obesity-induced diabetes, we observe increased beta cell death and impaired autophagic flux. We hypothesized that intermittent fasting, a clinically sustainable therapeutic strategy, stimulates autophagic flux to ameliorate obesity-induced diabetes. Our data show that despite continued high-fat intake, intermittent fasting restores autophagic flux in islets and improves glucose tolerance by enhancing glucose-stimulated insulin secretion, beta cell survival, and nuclear expression of NEUROG3, a marker of pancreatic regeneration. In contrast, intermittent fasting does not rescue beta-cell death or induce NEUROG3 expression in obese mice with lysosomal dysfunction secondary to deficiency of the lysosomal membrane protein, LAMP2 or haplo-insufficiency of BECN1/Beclin 1, a protein critical for autophagosome formation. Moreover, intermittent fasting is sufficient to provoke beta cell death in nonobese lamp2 null mice, attesting to a critical role for lysosome function in beta cell homeostasis under fasting conditions. Beta cells in intermittently-fasted LAMP2- or BECN1-deficient mice exhibit markers of autophagic failure with accumulation of damaged mitochondria and upregulation of oxidative stress. Thus, intermittent fasting preserves organelle quality via the autophagy-lysosome pathway to enhance beta cell survival and stimulates markers of regeneration in obesity-induced diabetes.

THE EFFECT OF INTERMITTENT GYRO-SCALE SLAB TURBULENCE ON PARALLEL AND PERPENDICULAR COSMIC-RAY TRANSPORT

Energy Technology Data Exchange (ETDEWEB)

Le Roux, J. A. [Department of Physics, University of Alabama in Huntsville, Huntsville, AL 35899 (United States)

2011-12-10

Earlier work based on nonlinear guiding center (NLGC) theory suggested that perpendicular cosmic-ray transport is diffusive when cosmic rays encounter random three-dimensional magnetohydrodynamic turbulence dominated by uniform two-dimensional (2D) turbulence with a minor uniform slab turbulence component. In this approach large-scale perpendicular cosmic-ray transport is due to cosmic rays microscopically diffusing along the meandering magnetic field dominated by 2D turbulence because of gyroresonant interactions with slab turbulence. However, turbulence in the solar wind is intermittent and it has been suggested that intermittent turbulence might be responsible for the observation of 'dropout' events in solar energetic particle fluxes on small scales. In a previous paper le Roux et al. suggested, using NLGC theory as a basis, that if gyro-scale slab turbulence is intermittent, large-scale perpendicular cosmic-ray transport in weak uniform 2D turbulence will be superdiffusive or subdiffusive depending on the statistical characteristics of the intermittent slab turbulence. In this paper we expand and refine our previous work further by investigating how both parallel and perpendicular transport are affected by intermittent slab turbulence for weak as well as strong uniform 2D turbulence. The main new finding is that both parallel and perpendicular transport are the net effect of an interplay between diffusive and nondiffusive (superdiffusive or subdiffusive) transport effects as a consequence of this intermittency.

Viral Advertising on Facebook in Vietnam

OpenAIRE

Tran, Phuong

2014-01-01

The purpose of this thesis is to explore which factors affect the effectiveness of viral advertising on Facebook in Vietnam. The quantitative research method is applied in this research and the sample is Vietnamese Facebook users. After the data analysis stage using SPSS, it became clear that weak ties, perceptual affinity and emotions have an impact on the effectiveness of viral advertising. The results provide a pratical implication of how to make an Ad which can go viral on Facebook. Moreo...

Effects of intermittent theta burst stimulation on cerebral blood flow and cerebral vasomotor reactivity.

Science.gov (United States)

Pichiorri, Floriana; Vicenzini, Edoardo; Gilio, Francesca; Giacomelli, Elena; Frasca, Vittorio; Cambieri, Chiara; Ceccanti, Marco; Di Piero, Vittorio; Inghilleri, Maurizio

2012-08-01

To determine whether intermittent theta burst stimulation influences cerebral hemodynamics, we investigated changes induced by intermittent theta burst stimulation on the middle cerebral artery cerebral blood flow velocity and vasomotor reactivity to carbon dioxide (CO(2)) in healthy participants. The middle cerebral artery flow velocity and vasomotor reactivity were monitored by continuous transcranial Doppler sonography. Changes in cortical excitability were tested by transcranial magnetic stimulation. In 11 healthy participants, before and immediately after delivering intermittent theta burst stimulation, we tested cortical excitability measured by the resting motor threshold and motor evoked potential amplitude over the stimulated hemisphere and vasomotor reactivity to CO(2) bilaterally. The blood flow velocity was monitored in both middle cerebral arteries throughout the experimental session. In a separate session, we tested the effects of sham stimulation under the same experimental conditions. Whereas the resting motor threshold remained unchanged before and after stimulation, motor evoked potential amplitudes increased significantly (P = .04). During and after stimulation, middle cerebral artery blood flow velocities also remained bilaterally unchanged, whereas vasomotor reactivity to CO(2) increased bilaterally (P = .04). The sham stimulation left all variables unchanged. The expected intermittent theta burst stimulation-induced changes in cortical excitability were not accompanied by changes in cerebral blood flow velocities; however, the bilateral increased vasomotor reactivity suggests that intermittent theta burst stimulation influences the cerebral microcirculation, possibly involving subcortical structures. These findings provide useful information on hemodynamic phenomena accompanying intermittent theta burst stimulation, which should be considered in research aimed at developing this noninvasive, low-intensity stimulation technique for safe

Intermittent fasting modulation of the diabetic syndrome in sand rats. II. In vivo investigations.

Science.gov (United States)

Belkacemi, Louiza; Selselet-Attou, Ghalem; Louchami, Karim; Sener, Abdullah; Malaisse, Willy J

2010-11-01

This study deals with the effects of daily intermittent fasting for 15 h upon the development of diabetes in sand rats exposed to a hypercaloric diet. The same pattern of daily intermittent fasting was imposed on sand rats maintained on a purely vegetal diet (control animals). Over the last 30 days of the present experiments, non-fasting animals gained weight, whilst intermittently fasting sand rats lost weight. In this respect, there was no significant difference between control animals and either diabetic or non-diabetic sand rats exposed to the hypercaloric diet. The postprandial glycemia remained fairly stable in the control animals. During a 3-week transition period from a purely vegetal to a hypercaloric diet, the post-prandial glycemia increased by 5.95 ± 1.26 mM (n=6) in diabetic sand rats, as distinct from an increase of only 0.45 ± 0.56 mM (n=6) in the non-diabetic animals. During the intermittent fasting period, the postprandial glycemia decreased significantly in the diabetic animals, but not so in the non-diabetic sand rats. Before the switch in food intake, the peak glycemia at the 30th min of an intraperitoneal glucose tolerance test was already higher in the diabetic than non-diabetic rats. In both the non-diabetic and diabetic sand rats, intermittent fasting prevented the progressive deterioration of glucose tolerance otherwise observed in non-fasting animals. These findings reveal that, at least in sand rats, intermittent daily fasting prevents the progressive deterioration of glucose tolerance otherwise taking place when these animals are exposed to a hypercaloric diet.

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.)

Consensus for linear multi-agent system with intermittent information transmissions using the time-scale theory

Science.gov (United States)

Taousser, Fatima; Defoort, Michael; Djemai, Mohamed

2016-01-01

This paper investigates the consensus problem for linear multi-agent system with fixed communication topology in the presence of intermittent communication using the time-scale theory. Since each agent can only obtain relative local information intermittently, the proposed consensus algorithm is based on a discontinuous local interaction rule. The interaction among agents happens at a disjoint set of continuous-time intervals. The closed-loop multi-agent system can be represented using mixed linear continuous-time and linear discrete-time models due to intermittent information transmissions. The time-scale theory provides a powerful tool to combine continuous-time and discrete-time cases and study the consensus protocol under a unified framework. Using this theory, some conditions are derived to achieve exponential consensus under intermittent information transmissions. Simulations are performed to validate the theoretical results.

Effects of acute intermittent hypoxia on glucose metabolism in awake healthy volunteers

OpenAIRE

Louis, Mariam; Punjabi, Naresh M.

2009-01-01

Accumulating evidence suggests that obstructive sleep apnea is associated with alterations in glucose metabolism. Although the pathophysiology of metabolic dysfunction in obstructive sleep apnea is not well understood, studies of murine models indicate that intermittent hypoxemia has an important contribution. However, corroborating data on the metabolic effects of intermittent hypoxia on glucose metabolism in humans are not available. Thus the primary aim of this study was to characterize th...

Intermittent Water Supplies: Challenges and Opportunities for Residential Water Users in Jordan

OpenAIRE

Rosenberg, David E.; Talozi, Samer; Lund, Jay

2008-01-01

Intermittent access to improved urban water supplies is a large and expanding global problem. This paper describes 16 supply enhancement and 23 demand management actions available to urban residential water users in Jordan to cope with intermittent supplies. We characterize actions by implementation, costs, and water quantities and qualities acquired or conserved. This effort systematically identifies potential options prior to detailed study and shows that water users have significant capaci...

HIV Viral Load: MedlinePlus Lab Test Information

Science.gov (United States)

... this page: https://medlineplus.gov/labtests/hivviralload.html HIV Viral Load To use the sharing features on this page, please enable JavaScript. What is an HIV Viral Load? An HIV viral load is a ...

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

Origins and challenges of viral dark matter.

Science.gov (United States)

Krishnamurthy, Siddharth R; Wang, David

2017-07-15

The accurate classification of viral dark matter - metagenomic sequences that originate from viruses but do not align to any reference virus sequences - is one of the major obstacles in comprehensively defining the virome. Depending on the sample, viral dark matter can make up from anywhere between 40 and 90% of sequences. This review focuses on the specific nature of dark matter as it relates to viral sequences. We identify three factors that contribute to the existence of viral dark matter: the divergence and length of virus sequences, the limitations of alignment based classification, and limited representation of viruses in reference sequence databases. We then discuss current methods that have been developed to at least partially circumvent these limitations and thereby reduce the extent of viral dark matter. Copyright © 2017 Elsevier B.V. All rights reserved.

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.

Coexistence for an Almost Periodic Predator-Prey Model with Intermittent Predation Driven by Discontinuous Prey Dispersal

Directory of Open Access Journals (Sweden)

Yantao Luo

2017-01-01

Full Text Available An almost periodic predator-prey model with intermittent predation and prey discontinuous dispersal is studied in this paper, which differs from the classical continuous and impulsive dispersal predator-prey models. The intermittent predation behavior of the predator species only happens in the channels between two patches where the discontinuous migration movement of the prey species occurs. Using analytic approaches and comparison theorems of the impulsive differential equations, sufficient criteria on the boundedness, permanence, and coexistence for this system are established. Finally, numerical simulations demonstrate that, for an intermittent predator-prey model, both the intermittent predation and intrinsic growth rates of the prey and predator species can greatly impact the permanence, extinction, and coexistence of the population.

Sensing and characterization of EMI during intermittent connector anomalies

Data.gov (United States)

National Aeronautics and Space Administration — This paper presents a new on-line methodology for detecting intermittent disconnection failures. The detection principle operates on the fundamental Lorentz Law that...

Design and setup of intermittent-flow respirometry system for aquatic organisms

DEFF Research Database (Denmark)

Svendsen, Morten Bo Søndergaard; Bushnell, P.G.; Steffensen, John Fleng

2016-01-01

Intermittent-flow respirometry is an experimental protocol for measuring oxygen consumption in aquatic organisms that utilizes the best features of closed (stop-flow) and flow-through respirometry while eliminating (or at least reducing) some of their inherent problems. By interspersing short...... and software further reduces error by allowing many measurements to be made over long periods thereby minimizing animal stress due to acclimation issues. This paper describes some of the fundamental principles that need to be considered when designing and carrying out automated intermittent-flow respirometry...

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

Analysis of residual chlorine in simple drinking water distribution system with intermittent water supply

Science.gov (United States)

Goyal, Roopali V.; Patel, H. M.

2015-09-01

Knowledge of residual chlorine concentration at various locations in drinking water distribution system is essential final check to the quality of water supplied to the consumers. This paper presents a methodology to find out the residual chlorine concentration at various locations in simple branch network by integrating the hydraulic and water quality model using first-order chlorine decay equation with booster chlorination nodes for intermittent water supply. The explicit equations are developed to compute the residual chlorine in network with a long distribution pipe line at critical nodes. These equations are applicable to Indian conditions where intermittent water supply is the most common system of water supply. It is observed that in intermittent water supply, the residual chlorine at farthest node is sensitive to water supply hours and travelling time of chlorine. Thus, the travelling time of chlorine can be considered to justify the requirement of booster chlorination for intermittent water supply.

Good Friends, Bad News - Affect and Virality in Twitter

DEFF Research Database (Denmark)

Hansen, Lars Kai; Arvidsson, Adam; Nielsen, Finn Årup

2011-01-01

The link between affect, defined as the capacity for sentimental arousal on the part of a message, and virality, defined as the probability that it be sent along, is of significant theoretical and practical importance, e.g. for viral marketing. The basic measure of virality in Twitter is the prob......The link between affect, defined as the capacity for sentimental arousal on the part of a message, and virality, defined as the probability that it be sent along, is of significant theoretical and practical importance, e.g. for viral marketing. The basic measure of virality in Twitter...

Smoking Habits of Patients Undergoing Treatment for Intermittent Claudication in the Vascular Quality Initiative.

Science.gov (United States)

Gabel, Joshua; Jabo, Brice; Patel, Sheela; Kiang, Sharon; Bianchi, Christian; Chiriano, Jason; Teruya, Theodore; Abou-Zamzam, Ahmed M

2017-10-01

Society for Vascular Surgery practice guidelines for the medical treatment of intermittent claudication give a GRADE 1A recommendation for smoking cessation. Active smoking is therefore expected to be low in patients suffering from intermittent claudication selected for vascular surgical intervention. The aim of this study is to evaluate the prevalence of smoking in patients undergoing intervention for intermittent claudication at the national level and to determine the relationship between smoking status and intervention. The Vascular Quality Initiative (VQI) registries for infra-inguinal bypass, supra-inguinal bypass, and peripheral vascular intervention (PVI) were queried to identify patients who underwent invasive treatment for intermittent claudication. Patient factors, procedure type (bypass versus PVI), and level of disease (supra-inguinal versus infra-inguinal) were evaluated for associations with smoking status (active smoking or nonsmoking) by univariate and covariate analysis. Between 2010 and 2015, 101,055 procedures were entered in the 3 registries, with 40,269 (40%) performed for intermittent claudication. Complete data for analysis were present in 37,632 cases. At the time of intervention, 44% of patients were active smokers, with wide variation by regional quality group (16-53%). In covariate analysis, active smoking at treatment was associated with age smoking status. During follow-up, 36% of patients had quit smoking. Predictors of smoking cessation included age ≥70 years (RR 1.45), ABI ≥0.9 (RR 1.12), and bypass procedures (RR 1.22). At the time of treatment, 44% of patients undergoing intervention for intermittent claudication in the VQI were active smokers and there was a wide regional variation. Prevalence of active smoking was greater in the presence of younger age, fewer comorbidities, lower ABI, and supra-inguinal disease. Type of procedure performed, and in turn level of invasiveness required, did not appear to be influenced by smoking

Multistate intermittency on the route to chaos of a semiconductor laser subjected to optical feedback from a long external cavity.

Science.gov (United States)

Choi, Daeyoung; Wishon, Michael J; Chang, C Y; Citrin, D S; Locquet, A

2018-01-01

We observe experimentally two regimes of intermittency on the route to chaos of a semiconductor laser subjected to optical feedback from a long external cavity as the feedback level is increased. The first regime encountered corresponds to multistate intermittency involving two or three states composed of several combinations of periodic, quasiperiodic, and subharmonic dynamics. The second regime is observed for larger feedback levels and involves intermittency between period-doubled and chaotic regimes. This latter type of intermittency displays statistical properties similar to those of on-off intermittency.

Intermittent fasting modulates IgA levels in the small intestine under intense stress: a mouse model.

Science.gov (United States)

Lara-Padilla, Eleazar; Godínez-Victoria, Marycarmen; Drago-Serrano, Maria Elisa; Reyna-Garfias, Humberto; Arciniega-Martínez, Ivonne Maciel; Abarca-Rojano, Edgar; Cruz-Hernández, Teresita Rocío; Campos-Rodríguez, Rafael

2015-08-15

Intermittent fasting prolongs the lifespan and unlike intense stress provides health benefits. Given the role of the immunoglobulin A (IgA) in the intestinal homeostasis, the aim of this study was to assess the impact of intermittent fasting plus intense stress on secretory IgA (SIgA) production and other mucosal parameters in the duodenum and ileum. Two groups of six mice, with intermittent fasting or fed ad libitum for 12weeks, were submitted to a session of intense stress by a bout of forced swimming. Unstressed ad libitum fed or intermittently fasted groups were included as controls. After sacrifice, we evaluated intestinal SIgA and plasma adrenal hormones, lamina propria IgA+ plasma-cells, mRNA expression of polymeric immunoglobulin receptor, α- and J-chains in the liver and intestinal mucosa, as well as pro- (tumor necrosis factor-α, interleukin-6 and Interferon-γ) and anti- (interleukin-2, -4, -10 and transforming growth factor-β) inflammatory cytokines in mucosal samples. Under intense stress, intermittent fasting down- or up-modulated the levels of most parameters in the duodenum and ileum, respectively while up-regulated corticosterone levels without affecting epinephrine. Our data suggest intermittent fasting plus intense stress elicited neuroendocrine pathways that differentially controlled IgA and pIgR expression in duodenum and ileum. These findings provide experimental foundations for a presumable impact of intermittent fasting under intense stress on the intestinal homeostasis or inflammation by triggering or reducing the IgA production in ileum or duodenum respectively. Copyright © 2015 Elsevier B.V. All rights reserved.

A qualitative descriptive study of self-management issues in people with long-term intermittent urinary catheters.

Science.gov (United States)

Wilde, Mary H; Brasch, Judith; Zhang, Yi

2011-06-01

The study was to identify and describe issues of intermittent urinary catheter users for future self-management research and/or training programmes. Limited studies were found of how people using clean intermittent catheterization manage their daily routines or troubleshoot problems. Self-management research related to intermittent catheterization could lead to improved compliance with the method and better quality of life. This qualitative descriptive study involved in-depth tape-recorded telephone interviews in 2008-2009 with 34 people in the United States of America using permanent intermittent catheterization, mostly individuals with spinal cord injury or multiple sclerosis. Recruitment was through Internet sites where individuals could link to the study website and then contact the researchers. The sample included 13 men and 21 women aged 21-72 years (mean 42 years). Content analysis for qualitative data involved iterative comparisons of transcripts, summaries and memos. Coding, key quotes and tables were developed to determine themes. Six major themes were identified: Knowing the Body, Practising Intermittent Catheterization, Limited Options in Catheters and Equipment, Inaccessible Bathrooms, Hassles, and Adjustment in Making Intermittent Catheterization a Part of Life. While some persons had choices in catheters, many did not because of insurance constraints. Some individuals developed knowledge of how to balance the procedure with fluid intake and activities. The lack of acceptable bathrooms can interfere with being able to go to work, travel or be with friends and family. All using intermittent catheterization should have adequate insurance coverage when this is needed. Research into training programmes could incorporate knowledge of experienced users. © 2011 Blackwell Publishing Ltd.

Influence of intermittent pressure, fluid flow, and mixing on the regenerative properties of articular chondrocytes.

Science.gov (United States)

Carver, S E; Heath, C A

1999-11-05

Equine articular chondrocytes, embedded within a polyglycolic acid nonwoven mesh, were cultured with various combinations of intermittent pressure, fluid flow, and mixing to examine the effects of different physical stimuli on neochondrogenesis from young cells. The cell/polymer constructs were cultured first in 125 ml spinner flasks for 1, 2, or 4 weeks and then in a perfusion system with intermittent pressure for a total of up to 6 weeks. Additional constructs were either cultured for all 6 weeks in the spinner flasks or for 1 week in spinners followed by 5 weeks in the perfusion system without intermittent pressure. Tissue constructs cultivated for 2 or 4 weeks in spinner flasks followed by perfusion with intermittent pressure had significantly higher concentrations of both sulfated glycosaminoglycan and collagen than constructs cultured entirely in spinners or almost entirely in the pressure/perfusion system. Initial cultivation in the spinner flasks, with turbulent mixing, enhanced both cell attachment and early development of the extracellular matrix. Subsequent culture with perfusion and intermittent pressure appeared to accelerate matrix formation. While the correlation was much stronger in the pressurized constructs, the compressive modulus was directly proportional to the concentration of sulfated glycosaminoglycan in all physically stressed constructs. Constructs that were not stressed beyond the 1-week seeding period lost mechanical integrity upon harvest, suggesting that physical stimulation, particularly with intermittent pressure, of immature tissue constructs during their development may contribute to their ultimate biomechanical functionality. Copyright 1999 John Wiley & Sons, Inc.

Time limit and time at VO2max' during a continuous and an intermittent run.

Science.gov (United States)

Demarie, S; Koralsztein, J P; Billat, V

2000-06-01

The purpose of this study was to verify, by track field tests, whether sub-elite runners (n=15) could (i) reach their VO2max while running at v50%delta, i.e. midway between the speed associated with lactate threshold (vLAT) and that associated with maximal aerobic power (vVO2max), and (ii) if an intermittent exercise provokes a maximal and/or supra maximal oxygen consumption longer than a continuous one. Within three days, subjects underwent a multistage incremental test during which their vVO2max and vLAT were determined; they then performed two additional testing sessions, where continuous and intermittent running exercises at v50%delta were performed up to exhaustion. Subject's gas exchange and heart rate were continuously recorded by means of a telemetric apparatus. Blood samples were taken from fingertip and analysed for blood lactate concentration. In the continuous and the intermittent tests peak VO2 exceeded VO2max values, as determined during the incremental test. However in the intermittent exercise, peak VO2, time to exhaustion and time at VO2max reached significantly higher values, while blood lactate accumulation showed significantly lower values than in the continuous one. The v50%delta is sufficient to stimulate VO2max in both intermittent and continuous running. The intermittent exercise results better than the continuous one in increasing maximal aerobic power, allowing longer time at VO2max and obtaining higher peak VO2 with lower lactate accumulation.

Scaling forecast models for wind turbulence and wind turbine power intermittency

Science.gov (United States)

Duran Medina, Olmo; Schmitt, Francois G.; Calif, Rudy

2017-04-01

The intermittency of the wind turbine power remains an important issue for the massive development of this renewable energy. The energy peaks injected in the electric grid produce difficulties in the energy distribution management. Hence, a correct forecast of the wind power in the short and middle term is needed due to the high unpredictability of the intermittency phenomenon. We consider a statistical approach through the analysis and characterization of stochastic fluctuations. The theoretical framework is the multifractal modelisation of wind velocity fluctuations. Here, we consider three wind turbine data where two possess a direct drive technology. Those turbines are producing energy in real exploitation conditions and allow to test our forecast models of power production at a different time horizons. Two forecast models were developed based on two physical principles observed in the wind and the power time series: the scaling properties on the one hand and the intermittency in the wind power increments on the other. The first tool is related to the intermittency through a multifractal lognormal fit of the power fluctuations. The second tool is based on an analogy of the power scaling properties with a fractional brownian motion. Indeed, an inner long-term memory is found in both time series. Both models show encouraging results since a correct tendency of the signal is respected over different time scales. Those tools are first steps to a search of efficient forecasting approaches for grid adaptation facing the wind energy fluctuations.

Detection of human parvovirus 4 viremia in the follow-up blood samples from seropositive individuals suggests the existence of persistent viral replication or reactivation of latent viral infection.

Science.gov (United States)

Chen, Mao-Yuan; Hung, Chien-Ching; Lee, Kuang-Lun

2015-06-19

The transmission routes for human parvovirus 4 (PARV4) infections in areas with high seroprevalence are not known. In the work described here, persistent PARV4 viral replication was investigated by conducting a longitudinal study. Ten healthcare workers each provided a blood sample at the beginning of the study (first sample) and 12 months later (second sample). The paired samples were tested for PARV4-positivity by immunoblotting analysis and nested polymerase chain reactions. IgG antibodies against PARV4 were detected in six participants, three of whom also had IgM antibodies against PARV4. The immunoblotting results did not vary over time. PARV4 DNA was detected in the first blood sample from one participant who had IgG antibodies against PARV4 and in the second blood samples from 2 participants who had IgG and IgM antibodies against PARV4. Detection of PARV4 DNA in the second blood samples from two seropositive participants suggests the existence of persistent PARV4 replication or reactivation of inactive virus in the tissues. The finding of persistent or intermittent PARV4 replication in individuals with past infections provides an important clue toward unraveling the non-parenteral transmission routes of PARV4 infection in areas where the virus is endemic.

On the moment-order, multiplicity and transverse-momentum dependences of intermittency in hadron-hadron collisions

International Nuclear Information System (INIS)

Wu Yuanfang; Liu Lianshou

1991-01-01

The dependences of intermittency degree on moment-order, multiplicity and transverse momentum are discussed. It is pointed out that the difference between the dependences of the anomalous exponents of factorial moments on moment-order at energies lower and higher than top ISR energy implies that the dependences of intermittency degree on multiplicity are in opposite directions in the two energy regions. It is argued that these different trends imply that intermittency degree depends on other more basic quantity, such as transverse momentum. These assertions and their deductions remain to be examined experimentally

A novel approach of collision assessment for coastal radar surveillance

International Nuclear Information System (INIS)

Ma, Feng; Chen, Yu-wang; Huang, Zi-chao; Yan, Xin-ping; Wang, Jin

2016-01-01

For coastal radar surveillance, this paper proposes a data-driven approach to estimate a blip's collision probability preliminarily based on two factors: the probability of it being a moving vessel and the collision potential of its position. The first factor is determined by a Directed Acyclic Graph (DAG), whose nodes represent the blip's characteristics, including the velocity, direction and size. Additionally, the structure and conditional probability tables of the DAG can be learned from verified samples. Subsequently, obstacles in a waterway can be described as collision potential fields using an Artificial Potential Field model, and the corresponding coefficients can be trained in accordance with the historical vessel distribution. Then, the other factor, the positional collision potential of any position is obtained through overlapping all the collision potential fields. For simplicity, only static obstacles have been considered. Eventually, the two factors are characterised as evidence, and the collision probability of a blip is estimated by combining them with Dempster's rule. Through ranking blips on collision probabilities, those that pose high threat to safety can be picked up in advance to remind radar operators. Particularly, a good agreement between the proposed approach and the manual operation was found in a preliminary test. - Highlights: • Novel estimation approach of collision probability for radar blips. • Novel method to evaluate the positional collision potentials using the APF model. • Novel method to obtain the coefficients of potential fields with historical data.

What makes a marketing campaing a viral success? : A descriptive model exploring the mechanisms of viral marketing

OpenAIRE

Stålnacke Larsson, Richard; Odén, Niklas

2011-01-01

What makes some marketing campaigns so immensely big and well known when they are marketed through social media or with a viral approach? How can a company reach out to customers through viral marketing and how can they make use of today’s social media to achieve it? In this article we will try to understand and further explore what a campaign have to accomplish in order to achieve a viral spread, using a descriptive model which uses a number of factors and terms necessary in order to properl...

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.)

Crisis induced intermittency in a fourth-order autonomous electric circuit

International Nuclear Information System (INIS)

Stouboulos, I.N.; Miliou, A.N.; Valaristos, A.P.; Kyprianidis, I.M.; Anagnostopoulos, A.N.

2007-01-01

The chaotic dynamics of a fourth-order autonomous nonlinear electric circuit has been studied. The circuit consists of two active elements, one linear negative conductance and one nonlinear resistor exhibiting a symmetrical piecewise-linear v-i characteristic and two capacitances C 1 and C 2 , which serve as the control parameters of the system. Experimental time series and the corresponding phase portraits were used to register the intermittent behaviour of the corresponding dynamical system between two interacting subattractors. The distribution of the times τ, between successive transitions from the one subattractor to the other indicates that a crisis induced intermittency occurs in the studied circuit

Outer synchronization of complex networks with internal delay and coupling delay via aperiodically intermittent pinning control

Science.gov (United States)

Zhang, Chuan; Wang, Xingyuan; Wang, Chunpeng; Xia, Zhiqiu

This paper concerns the outer synchronization problem between two complex delayed networks via the method of aperiodically intermittent pinning control. Apart from previous works, internal delay and coupling delay are both involved in this model, and the designed intermittent controllers can be aperiodic. The main work in this paper can be summarized as follows: First, two cases of aperiodically intermittent control with constant gain and adaptive gain are implemented, respectively. The intermittent control and pinning control are combined to reduce consumptions further. Then, based on the Lyapunov stability theory, synchronization protocols are given by strict derivation. Especially, the designed controllers are indeed simple and valid in application of theory to practice. Finally, numerical examples put the proposed control methods to the test.

Emerging Viral Diseases of Tomato Crops

NARCIS (Netherlands)

Hanssen, I.M.; Lapidot, M.; Thomma, B.P.H.J.

2010-01-01

Viral diseases are an important limiting factor in many crop production systems. Because antiviral products are not available, control strategies rely on genetic resistance or hygienic measures to prevent viral diseases, or on eradication of diseased crops to control such diseases. Increasing

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.

Intermittent magnetic reconnection in TS-3 merging experiment

International Nuclear Information System (INIS)

Ono, Y.; Hayashi, Y.; Ii, T.; Tanabe, H.; Ito, S.; Kuwahata, A.; Ito, T.; Kamino, Y.; Yamada, T.; Inomoto, M.

2011-01-01

Ejection of current sheet with plasma mass causes impulsive and intermittent magnetic reconnection in the TS-3 spherical tokamak (ST) merging experiment. Under high guide toroidal field, the sheet resistivity is almost classical due to the sheet thickness much longer than the ion gyroradius. Large inflow flux and low current-sheet resistivity result in flux and plasma pileup followed by rapid growth of the current sheet. When the pileup exceeds a critical limit, the sheet is ejected mechanically from the squeezed X-point area. The reconnection (outflow) speed is slow during the flux/plasma pileup and is fast during the ejection, suggesting that intermittent reconnection similar to the solar flare increases the averaged reconnection speed. These transient effects enable the merging tokamaks to have the fast reconnection as well as the high-power reconnection heating, even when their current-sheet resistivity is low under high guide field.

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

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

Seizure tests distinguish intermittent fasting from the ketogenic diet

Science.gov (United States)

Hartman, Adam L.; Zheng, Xiangrong; Bergbower, Emily; Kennedy, Michiko; Hardwick, J. Marie

2010-01-01

Summary Purpose Calorie restriction can be anticonvulsant in animal models. The ketogenic diet was designed to mimic calorie restriction and has been assumed to work by the same mechanisms. We challenged this assumption by profiling the effects of these dietary regimens in mice subjected to a battery of acute seizure tests. Methods Juvenile male NIH Swiss mice received ketogenic diet or a normal diet fed in restricted quantities (continuously or intermittently) for ~ 12 days, starting at 3–4 weeks of age. Seizures were induced by the 6 Hz test, kainic acid, maximal electroshock, or pentylenetetrazol. Results The ketogenic and calorie-restricted diets often had opposite effects depending on the seizure test. The ketogenic diet protected from 6 Hz–induced seizures, whereas calorie restriction (daily and intermittent) increased seizure activity. Conversely, calorie restriction protected juvenile mice against seizures induced by kainic acid, whereas the ketogenic diet failed to protect. Intermittent caloric restriction worsened seizures induced by maximal electroshock but had no effect on those induced by pentylenetetrazol. Discussion In contrast to a longstanding hypothesis, calorie restriction and the ketogenic diet differ in their acute seizure test profiles, suggesting that they have different underlying anticonvulsant mechanisms. These findings highlight the importance of the 6 Hz test and its ability to reflect the benefits of ketosis and fat consumption. PMID:20477852

Seizure tests distinguish intermittent fasting from the ketogenic diet.

Science.gov (United States)

Hartman, Adam L; Zheng, Xiangrong; Bergbower, Emily; Kennedy, Michiko; Hardwick, J Marie

2010-08-01

Calorie restriction can be anticonvulsant in animal models. The ketogenic diet was designed to mimic calorie restriction and has been assumed to work by the same mechanisms. We challenged this assumption by profiling the effects of these dietary regimens in mice subjected to a battery of acute seizure tests. Juvenile male NIH Swiss mice received ketogenic diet or a normal diet fed in restricted quantities (continuously or intermittently) for ∼12 days, starting at 3-4 weeks of age. Seizures were induced by the 6 Hz test, kainic acid, maximal electroshock, or pentylenetetrazol. The ketogenic and calorie-restricted diets often had opposite effects depending on the seizure test. The ketogenic diet protected from 6 Hz-induced seizures, whereas calorie restriction (daily and intermittent) increased seizure activity. Conversely, calorie restriction protected juvenile mice against seizures induced by kainic acid, whereas the ketogenic diet failed to protect. Intermittent caloric restriction worsened seizures induced by maximal electroshock but had no effect on those induced by pentylenetetrazol. In contrast to a longstanding hypothesis, calorie restriction and the ketogenic diet differ in their acute seizure test profiles, suggesting that they have different underlying anticonvulsant mechanisms. These findings highlight the importance of the 6 Hz test and its ability to reflect the benefits of ketosis and fat consumption. Wiley Periodicals, Inc. © 2010 International League Against Epilepsy.

Implementation of DMAs in Intermittent Water Supply Networks Based on Equity Criteria

OpenAIRE

Amilkar E. Ilaya-Ayza; Carlos Martins; Enrique Campbell; Joaquín Izquierdo

2017-01-01

Intermittent supply is a common way of delivering water in many developing countries. Limitations on water and economic resources, in addition to poor management and population growth, limit the possibilities of delivering water 24 h a day. Intermittent water supply networks are usually designed and managed in an empirical manner, or using tools and criteria devised for continuous supply systems, and this approach can produce supply inequity. In this paper, an approach based on the hydraulic ...

Sensitive detection of viral transcripts in human tumor transcriptomes.

Directory of Open Access Journals (Sweden)

Sven-Eric Schelhorn

Full Text Available In excess of 12% of human cancer incidents have a viral cofactor. Epidemiological studies of idiopathic human cancers indicate that additional tumor viruses remain to be discovered. Recent advances in sequencing technology have enabled systematic screenings of human tumor transcriptomes for viral transcripts. However, technical problems such as low abundances of viral transcripts in large volumes of sequencing data, viral sequence divergence, and homology between viral and human factors significantly confound identification of tumor viruses. We have developed a novel computational approach for detecting viral transcripts in human cancers that takes the aforementioned confounding factors into account and is applicable to a wide variety of viruses and tumors. We apply the approach to conducting the first systematic search for viruses in neuroblastoma, the most common cancer in infancy. The diverse clinical progression of this disease as well as related epidemiological and virological findings are highly suggestive of a pathogenic cofactor. However, a viral etiology of neuroblastoma is currently contested. We mapped 14 transcriptomes of neuroblastoma as well as positive and negative controls to the human and all known viral genomes in order to detect both known and unknown viruses. Analysis of controls, comparisons with related methods, and statistical estimates demonstrate the high sensitivity of our approach. Detailed investigation of putative viral transcripts within neuroblastoma samples did not provide evidence for the existence of any known human viruses. Likewise, de-novo assembly and analysis of chimeric transcripts did not result in expression signatures associated with novel human pathogens. While confounding factors such as sample dilution or viral clearance in progressed tumors may mask viral cofactors in the data, in principle, this is rendered less likely by the high sensitivity of our approach and the number of biological replicates

Prolapsing Gastric Polyp Causing Intermittent Gastric Outlet Obstruction.

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Kosai, Nik Ritza; Gendeh, Hardip Singh; Norfaezan, Abdul Rashid; Razman, Jamin; Sutton, Paul Anthony; Das, Srijit

2015-06-01

Gastric polyps are often an incidental finding on upper gastrointestinal endoscopy, with an incidence up to 5%. The majority of gastric polyps are asymptomatic, occurring secondary to inflammation. Prior reviews discussed Helicobacter pylori (H pylori)-associated singular gastric polyposis; however, we present a rare and unusual case of recurrent multiple benign gastric polyposis post H pylori eradication resulting in intermittent gastric outlet obstruction. A 70-year-old independent male, Chinese in ethnicity, with a background of diabetes mellitus, hypertension, and a simple renal cyst presented with a combination of melena, anemia, and intermittent vomiting of partially digested food after meals. Initial gastroscopy was positive for H pylori; thus he was treated with H pylori eradication and proton pump inhibitors. Serial gastroscopy demonstrated multiple sessile gastric antral polyps, the largest measuring 4 cm. Histopathologic examination confirmed a benign hyperplastic lesion. Computed tomography identified a pyloric mass with absent surrounding infiltration or metastasis. A distal gastrectomy was performed, whereby multiple small pyloric polyps were found, the largest prolapsing into the pyloric opening, thus explaining the intermittent nature of gastric outlet obstruction. Such polyps often develop from gastric ulcers and, if left untreated, may undergo neoplasia to form malignant cells. A distal gastrectomy was an effective choice of treatment, taking into account the polyp size, quantity, and potential for malignancy as opposed to an endoscopic approach, which may not guarantee a complete removal of safer margins and depth. Therefore, surgical excision is favorable for multiple large gastric polyps with risk of malignancy.

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

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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)

Intermittent Hypoxia Impairs Glucose Homeostasis in C57BL6/J Mice: Partial Improvement with Cessation of the Exposure

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Polak, Jan; Shimoda, Larissa A.; Drager, Luciano F.; Undem, Clark; McHugh, Holly; Polotsky, Vsevolod Y.; Punjabi, Naresh M.

2013-01-01

Objectives: Obstructive sleep apnea is associated with insulin resistance, glucose intolerance, and type 2 diabetes mellitus. Although several studies have suggested that intermittent hypoxia in obstructive sleep apnea may induce abnormalities in glucose homeostasis, it remains to be determined whether these abnormalities improve after discontinuation of the exposure. The objective of this study was to delineate the effects of intermittent hypoxia on glucose homeostasis, beta cell function, and liver glucose metabolism and to investigate whether the impairments improve after the hypoxic exposure is discontinued. Interventions: C57BL6/J mice were exposed to 14 days of intermittent hypoxia, 14 days of intermittent air, or 7 days of intermittent hypoxia followed by 7 days of intermittent air (recovery paradigm). Glucose and insulin tolerance tests were performed to estimate whole-body insulin sensitivity and calculate measures of beta cell function. Oxidative stress in pancreatic tissue and glucose output from isolated hepatocytes were also assessed. Results: Intermittent hypoxia increased fasting glucose levels and worsened glucose tolerance by 67% and 27%, respectively. Furthermore, intermittent hypoxia exposure was associated with impairments in insulin sensitivity and beta cell function, an increase in liver glycogen, higher hepatocyte glucose output, and an increase in oxidative stress in the pancreas. While fasting glucose levels and hepatic glucose output normalized after discontinuation of the hypoxic exposure, glucose intolerance, insulin resistance, and impairments in beta cell function persisted. Conclusions: Intermittent hypoxia induces insulin resistance, impairs beta cell function, enhances hepatocyte glucose output, and increases oxidative stress in the pancreas. Cessation of the hypoxic exposure does not fully reverse the observed changes in glucose metabolism. Citation: Polak J; Shimoda LA; Drager LF; Undem C; McHugh H; Polotsky VY; Punjabi NM

Viral marketing: the use of surprise

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Lindgreen, A.; Vanhamme, J.; Clarke, I.; Flaherty, T.B.

2005-01-01

Viral marketing involves consumers passing along a company's marketing message to their friends, family, and colleagues. This chapter reviews viral marketing campaigns and argues that the emotion of surprise often is at work and that this mechanism resembles that of word-of-mouth marketing.

Increasing walking in patients with intermittent claudication: Protocol for a randomised controlled trial

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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

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

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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.

Uncoupling protein-2 mRNA expression in mice subjected to intermittent hypoxia

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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.

Viral evasion of intracellular DNA and RNA sensing

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Chan, Ying Kai; Gack, Michaela U.

2016-01-01

The co-evolution of viruses with their hosts has led to the emergence of viral pathogens that are adept at evading or actively suppressing host immunity. Pattern recognition receptors (PRRs) are key components of antiviral immunity that detect conserved molecular features of viral pathogens and initiate signalling that results in the expression of antiviral genes. In this Review, we discuss the strategies that viruses use to escape immune surveillance by key intracellular sensors of viral RNA or DNA, with a focus on RIG-I-like receptors (RLRs), cyclic GMP–AMP synthase (cGAS) and interferon-γ (IFNγ)-inducible protein 16 (IFI16). Such viral strategies include the sequestration or modification of viral nucleic acids, interference with specific post-translational modifications of PRRs or their adaptor proteins, the degradation or cleavage of PRRs or their adaptors, and the sequestration or relocalization of PRRs. An understanding of viral immune-evasion mechanisms at the molecular level may guide the development of vaccines and antivirals. PMID:27174148

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

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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.

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

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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.

The effect of intermittent fasting on blood pressure variability in patients with newly diagnosed hypertension or prehypertension.

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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.

Molecular imaging of oncolytic viral therapy

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Dana Haddad

2014-01-01

Full Text Available Oncolytic viruses have made their mark on the cancer world as a potential therapeutic option, with the possible advantages of reduced side effects and strengthened treatment efficacy due to higher tumor selectivity. Results have been so promising, that oncolytic viral treatments have now been approved for clinical trials in several countries. However, clinical studies may benefit from the ability to noninvasively and serially identify sites of viral targeting via molecular imaging in order to provide safety, efficacy, and toxicity information. Furthermore, molecular imaging of oncolytic viral therapy may provide a more sensitive and specific diagnostic technique to detect tumor origin and, more importantly, presence of metastases. Several strategies have been investigated for molecular imaging of viral replication broadly categorized into optical and deep tissue imaging, utilizing several reporter genes encoding for fluorescence proteins, conditional enzymes, and membrane protein and transporters. Various imaging methods facilitate molecular imaging, including computer tomography, magnetic resonance imaging, positron emission tomography, single photon emission CT, gamma-scintigraphy, and photoacoustic imaging. In addition, several molecular probes are used for medical imaging, which act as targeting moieties or signaling agents. This review will explore the preclinical and clinical use of in vivo molecular imaging of replication-competent oncolytic viral therapy.

Pediatric Viral Exanthema: A Review Article

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Mohammed Jafar Saffar

2017-04-01

Full Text Available Context Many diseases caused by viral agents are associated with fever and cutaneous manifestations. Viral exanthema is a widespread nonspecific skin rash, commonly characterized by generalized eruption of erythematous macules and papular lesions. Although these rashes are mostly benign and self-limited, some may be serious and life-threatening. Differentiation between severe and benign types is clinically important and life-saving. Evidence Acquisition In this narrative review, electronic databases, including Google Scholar, Science Direct, PubMed (including Medline, Web of Science, Scientific Information Database, and Scopus, were searched. We conducted a narrative review of papers published on pediatric viral exanthema during 2000 - 2016. The used keywords included “viral exanthema”, “fever”, and “skin rash”. Articles on skin rash, caused by drug reactions or nonviral exanthema, were excluded. Results Different viral agents can cause different types of skin reactions. Cutaneous manifestations and skin rashes can be categorized, based on the form of the rash (macular, papular, vesicular, blistery, petechial, and purpuric or the general term, which denotes illnesses such as measles-like morbilliform rash, rubella or rubelliform rash, and scarlatiniform rash, a scarlet-fever like infection. Conclusions Based on the findings, a systematic approach relying on accurate history-taking and analysis of epidemiological cues and rash characteristics is of great significance.

Intermittent hypoxia impairs glucose homeostasis in C57BL6/J mice: partial improvement with cessation of the exposure.

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Polak, Jan; Shimoda, Larissa A; Drager, Luciano F; Undem, Clark; McHugh, Holly; Polotsky, Vsevolod Y; Punjabi, Naresh M

2013-10-01

Obstructive sleep apnea is associated with insulin resistance, glucose intolerance, and type 2 diabetes mellitus. Although several studies have suggested that intermittent hypoxia in obstructive sleep apnea may induce abnormalities in glucose homeostasis, it remains to be determined whether these abnormalities improve after discontinuation of the exposure. The objective of this study was to delineate the effects of intermittent hypoxia on glucose homeostasis, beta cell function, and liver glucose metabolism and to investigate whether the impairments improve after the hypoxic exposure is discontinued. C57BL6/J mice were exposed to 14 days of intermittent hypoxia, 14 days of intermittent air, or 7 days of intermittent hypoxia followed by 7 days of intermittent air (recovery paradigm). Glucose and insulin tolerance tests were performed to estimate whole-body insulin sensitivity and calculate measures of beta cell function. Oxidative stress in pancreatic tissue and glucose output from isolated hepatocytes were also assessed. Intermittent hypoxia increased fasting glucose levels and worsened glucose tolerance by 67% and 27%, respectively. Furthermore, intermittent hypoxia exposure was associated with impairments in insulin sensitivity and beta cell function, an increase in liver glycogen, higher hepatocyte glucose output, and an increase in oxidative stress in the pancreas. While fasting glucose levels and hepatic glucose output normalized after discontinuation of the hypoxic exposure, glucose intolerance, insulin resistance, and impairments in beta cell function persisted. Intermittent hypoxia induces insulin resistance, impairs beta cell function, enhances hepatocyte glucose output, and increases oxidative stress in the pancreas. Cessation of the hypoxic exposure does not fully reverse the observed changes in glucose metabolism.

Oxygen tension level and human viral infections

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Morinet, Frédéric, E-mail: frederic.morinet@sls.aphp.fr [Centre des Innovations Thérapeutiques en Oncologie et Hématologie (CITOH), CHU Saint-Louis, Paris (France); Université Denis Diderot, Sorbonne Paris Cité Paris, Paris (France); Casetti, Luana [Institut Cochin INSERM U1016, Paris (France); François, Jean-Hugues; Capron, Claude [Institut Cochin INSERM U1016, Paris (France); Laboratoire d' Hématologie, Hôpital Ambroise Paré, Boulogne (France); Université de Versailles Saint-Quentin en Yvelynes, Versailles (France); Pillet, Sylvie [Laboratoire de Bactériologie-Virologie-Hygiène, CHU de Saint-Etienne, Saint-Etienne (France); Université de Lyon et Université de Saint-Etienne, Jean Monnet, GIMAP EA3064, F-42023 Saint-Etienne, Lyon (France)

2013-09-15

The role of oxygen tension level is a well-known phenomenon that has been studied in oncology and radiotherapy since about 60 years. Oxygen tension may inhibit or stimulate propagation of viruses in vitro as well as in vivo. In turn modulating oxygen metabolism may constitute a novel approach to treat viral infections as an adjuvant therapy. The major transcription factor which regulates oxygen tension level is hypoxia-inducible factor-1 alpha (HIF-1α). Down-regulating the expression of HIF-1α is a possible method in the treatment of chronic viral infection such as human immunodeficiency virus infection, chronic hepatitis B and C viral infections and Kaposi sarcoma in addition to classic chemotherapy. The aim of this review is to supply an updating concerning the influence of oxygen tension level in human viral infections and to evoke possible new therapeutic strategies regarding this environmental condition. - Highlights: • Oxygen tension level regulates viral replication in vitro and possibly in vivo. • Hypoxia-inducible factor 1 (HIF-1α) is the principal factor involved in Oxygen tension level. • HIF-1α upregulates gene expression for example of HIV, JC and Kaposi sarcoma viruses. • In addition to classical chemotherapy inhibition of HIF-1α may constitute a new track to treat human viral infections.

Rituximab-related viral infections in lymphoma patients.

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Aksoy, Sercan; Harputluoglu, Hakan; Kilickap, Saadettin; Dede, Didem Sener; Dizdar, Omer; Altundag, Kadri; Barista, Ibrahim

2007-07-01

Recently, a human/mouse chimeric monoclonal antibody, rituximab, has been successfully used to treat cases of B-cell non-Hodgkin's lymphoma and some autoimmune diseases. However, several viral infections related to rituximab have been reported in the literature, but were not well characterized. To further investigate this topic, relevant English language studies were identified through Medline. There were 64 previously reported cases of serious viral infection after rituximab treatment. The median age of the cases was 61 years (range: 21 - 79). The median time period from the start of rituximab treatment to viral infection diagnosis was 5.0 months (range: 1 - 20). The most frequently experienced viral infections were hepatitis B virus (HBV) (39.1%, n = 25), cytomegalovirus infection (CMV) (23.4%, n = 15), varicella-zoster virus (VZV) (9.4%, n = 6), and others (28.1%, n = 18). Of the patients with HBV infections, 13 (52.0%) died due to hepatic failure. Among the 39 cases that had viral infections other than HBV, 13 died due to these specific infections. In this study, about 50% of the rituximab-related HBV infections resulted in death, whereas this was the case in only 33% of the cases with other infections. Close monitoring for viral infection, particularly HBV and CMV, in patients treated with rituximab should be recommended.

Viral vector-based influenza vaccines

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de Vries, Rory D.; Rimmelzwaan, Guus F.

2016-01-01

ABSTRACT Antigenic drift of seasonal influenza viruses and the occasional introduction of influenza viruses of novel subtypes into the human population complicate the timely production of effective vaccines that antigenically match the virus strains that cause epidemic or pandemic outbreaks. The development of game-changing vaccines that induce broadly protective immunity against a wide variety of influenza viruses is an unmet need, in which recombinant viral vectors may provide. Use of viral vectors allows the delivery of any influenza virus antigen, or derivative thereof, to the immune system, resulting in the optimal induction of virus-specific B- and T-cell responses against this antigen of choice. This systematic review discusses results obtained with vectored influenza virus vaccines and advantages and disadvantages of the currently available viral vectors. PMID:27455345

Multi-point observations of intermittency in the cusp regions

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M. M. Echim

2007-08-01

Full Text Available In this paper we investigate the statistical properties of magnetic field fluctuations measured by the four Cluster spacecraft in the cusp and close to the interface with the magnetospheric lobes, magnetopause and magnetosheath. At lower altitudes along the outbound orbit of 26 February 2001, the magnetic field fluctuations recorded by all four spacecraft are random and their Probability Distribution Functions (PDFs are Gaussian at all scales. The flatness parameter, F – related to the kurtosis of the time series, is equal to 3. At higher altitudes, in the cusp and its vicinity, closer to the interface with the magnetopause and magnetosheath, the PDFs from all Cluster satellites are non-Gaussian and show a clear intermittent behavior at scales smaller than τ_G≈ 61 s (or 170 km. The flatness parameter increases to values greater than 3 for scales smaller than τ_G. A Haar wavelet transform enables the identification of the "events" that produce sudden variations of the magnetic field and of the scales that have most of the power. The LIM parameter (i.e. normalized wavelet power indicates that events for scales below 65 s are non-uniformly distributed throughout the cusp passage. PDFs, flatness and wavelet analysis show that at coarse-grained scales larger than τ_G the intermittency is absent in the cusp. Fluctuations of the magnetic energy observed during the same orbit in the magnetosheath show PDFs that tend toward a Gaussian at scales smaller than τ_G found in the cusp. The flatness analysis confirms the decreasing of τ_G from cusp to magnetosheath. Our analysis reveals the turbulent cusp as a transition region from a non-intermittent turbulent state inside the magnetosphere to an intermittent turbulent state in the magnetosheath that has statistical properties resembling the solar wind turbulence. The observed turbulent fluctuations in the cusp suggests a phenomenon of nonlinear

Exposure to intermittent hypoxia and sustained hypercapnia reduces therapeutic CPAP in participants with obstructive sleep apnea.

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El-Chami, Mohamad; Sudan, Sukhesh; Lin, Ho-Sheng; Mateika, Jason H

2017-10-01

Our purpose was to determine whether exposure to mild intermittent hypoxia leads to a reduction in the therapeutic continuous positive airway pressure required to eliminate breathing events. Ten male participants were treated with twelve 2-min episodes of hypoxia ([Formula: see text] ≈50 mmHg) separated by 2-min intervals of normoxia in the presence of [Formula: see text] that was sustained 3 mmHg above baseline. During recovery from the last episode, the positive airway pressure was reduced in a stepwise fashion until flow limitation was evident. The participants also completed a sham protocol under normocapnic conditions, which mimicked the time frame of the intermittent hypoxia protocol. After exposure to intermittent hypoxia, the therapeutic pressure was significantly reduced (i.e., 5 cmH 2 O) without evidence of flow limitation (103.4 ± 6.3% of baseline, P = 0.5) or increases in upper airway resistance (95.6 ± 15.0% of baseline, P = 0.6). In contrast, a similar decrease in pressure was accompanied by flow limitation (77.0 ± 1.8% of baseline, P = 0.001) and an increase in upper airway resistance (167.2 ± 17.5% of baseline, P = 0.01) after the sham protocol. Consistent with the initiation of long-term facilitation of upper airway muscle activity, exposure to intermittent hypoxia reduced the therapeutic pressure required to eliminate apneic events that could improve treatment compliance. This possibility, coupled with the potentially beneficial effects of intermittent hypoxia on comorbidities linked to sleep apnea, suggests that mild intermittent hypoxia may have a multipronged therapeutic effect on sleep apnea. NEW & NOTEWORTHY Our new finding is that exposure to mild intermittent hypoxia reduced the therapeutic pressure required to treat sleep apnea. These findings are consistent with previous results, which have shown that long-term facilitation of upper muscle activity can be initiated following exposure to intermittent hypoxia in humans.

Spectral degeneracy and escape dynamics for intermittent maps with a hole

International Nuclear Information System (INIS)

Froyland, Gary; Stancevic, Ognjen; Murray, Rua

2011-01-01

We study intermittent maps from the point of view of metastability. Small neighbourhoods of an intermittent fixed point and their complements form pairs of almost-invariant sets. Treating the small neighbourhood as a hole, we first show that the absolutely continuous conditional invariant measures (ACCIMs) converge to the ACIM as the length of the small neighbourhood shrinks to zero. We then quantify how the escape dynamics from these almost-invariant sets are connected with the second eigenfunctions of Perron–Frobenius (transfer) operators when a small perturbation is applied near the intermittent fixed point. In particular, we describe precisely the scaling of the second eigenvalue with the perturbation size, provide upper and lower bounds and demonstrate L 1 convergence of the positive part of the second eigenfunction to the ACIM as the perturbation goes to zero. This perturbation and associated eigenvalue scalings and convergence results are all compatible with Ulam's method and provide a formal explanation for the numerical behaviour of Ulam's method in this nonuniformly hyperbolic setting. The main results of the paper are illustrated with numerical computations

Canonical Cortical Circuit Model Explains Rivalry, Intermittent Rivalry, and Rivalry Memory.

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Shashaank Vattikuti

2016-05-01

Full Text Available It has been shown that the same canonical cortical circuit model with mutual inhibition and a fatigue process can explain perceptual rivalry and other neurophysiological responses to a range of static stimuli. However, it has been proposed that this model cannot explain responses to dynamic inputs such as found in intermittent rivalry and rivalry memory, where maintenance of a percept when the stimulus is absent is required. This challenges the universality of the basic canonical cortical circuit. Here, we show that by including an overlooked realistic small nonspecific background neural activity, the same basic model can reproduce intermittent rivalry and rivalry memory without compromising static rivalry and other cortical phenomena. The background activity induces a mutual-inhibition mechanism for short-term memory, which is robust to noise and where fine-tuning of recurrent excitation or inclusion of sub-threshold currents or synaptic facilitation is unnecessary. We prove existence conditions for the mechanism and show that it can explain experimental results from the quartet apparent motion illusion, which is a prototypical intermittent rivalry stimulus.

De novo assembly of highly diverse viral populations

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Yang Xiao

2012-09-01

Full Text Available Abstract Background Extensive genetic diversity in viral populations within infected hosts and the divergence of variants from existing reference genomes impede the analysis of deep viral sequencing data. A de novo population consensus assembly is valuable both as a single linear representation of the population and as a backbone on which intra-host variants can be accurately mapped. The availability of consensus assemblies and robustly mapped variants are crucial to the genetic study of viral disease progression, transmission dynamics, and viral evolution. Existing de novo assembly techniques fail to robustly assemble ultra-deep sequence data from genetically heterogeneous populations such as viruses into full-length genomes due to the presence of extensive genetic variability, contaminants, and variable sequence coverage. Results We present VICUNA, a de novo assembly algorithm suitable for generating consensus assemblies from genetically heterogeneous populations. We demonstrate its effectiveness on Dengue, Human Immunodeficiency and West Nile viral populations, representing a range of intra-host diversity. Compared to state-of-the-art assemblers designed for haploid or diploid systems, VICUNA recovers full-length consensus and captures insertion/deletion polymorphisms in diverse samples. Final assemblies maintain a high base calling accuracy. VICUNA program is publicly available at: http://www.broadinstitute.org/scientific-community/science/projects/viral-genomics/ viral-genomics-analysis-software. Conclusions We developed VICUNA, a publicly available software tool, that enables consensus assembly of ultra-deep sequence derived from diverse viral populations. While VICUNA was developed for the analysis of viral populations, its application to other heterogeneous sequence data sets such as metagenomic or tumor cell population samples may prove beneficial in these fields of research.

Modeling and Optimization for Management of Intermittent Water Supply

Science.gov (United States)

Lieb, A. M.; Wilkening, J.; Rycroft, C.

2014-12-01

In many urban areas, 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 controlling valve parameters occurring as boundary conditions in a network model of transient, transition flow through closed pipes. Gradient-based optimization will be used to find boundary values to minimize pressure gradients and ensure equitable water availability at system endpoints.

Raw Sewage Harbors Diverse Viral Populations

Science.gov (United States)

Cantalupo, Paul G.; Calgua, Byron; Zhao, Guoyan; Hundesa, Ayalkibet; Wier, Adam D.; Katz, Josh P.; Grabe, Michael; Hendrix, Roger W.; Girones, Rosina; Wang, David; Pipas, James M.

2011-01-01

ABSTRACT At this time, about 3,000 different viruses are recognized, but metagenomic studies suggest that these viruses are a small fraction of the viruses that exist in nature. We have explored viral diversity by deep sequencing nucleic acids obtained from virion populations enriched from raw sewage. We identified 234 known viruses, including 17 that infect humans. Plant, insect, and algal viruses as well as bacteriophages were also present. These viruses represented 26 taxonomic families and included viruses with single-stranded DNA (ssDNA), double-stranded DNA (dsDNA), positive-sense ssRNA [ssRNA(+)], and dsRNA genomes. Novel viruses that could be placed in specific taxa represented 51 different families, making untreated wastewater the most diverse viral metagenome (genetic material recovered directly from environmental samples) examined thus far. However, the vast majority of sequence reads bore little or no sequence relation to known viruses and thus could not be placed into specific taxa. These results show that the vast majority of the viruses on Earth have not yet been characterized. Untreated wastewater provides a rich matrix for identifying novel viruses and for studying virus diversity. Importance At this time, virology is focused on the study of a relatively small number of viral species. Specific viruses are studied either because they are easily propagated in the laboratory or because they are associated with disease. The lack of knowledge of the size and characteristics of the viral universe and the diversity of viral genomes is a roadblock to understanding important issues, such as the origin of emerging pathogens and the extent of gene exchange among viruses. Untreated wastewater is an ideal system for assessing viral diversity because virion populations from large numbers of individuals are deposited and because raw sewage itself provides a rich environment for the growth of diverse host species and thus their viruses. These studies suggest that

Plasma Viral miRNAs Indicate a High Prevalence of Occult Viral Infections

Directory of Open Access Journals (Sweden)

Enrique Fuentes-Mattei

2017-06-01

Full Text Available Prevalence of Kaposi sarcoma-associated herpesvirus (KSHV/HHV-8 varies greatly in different populations. We hypothesized that the actual prevalence of KSHV/HHV8 infection in humans is underestimated by the currently available serological tests. We analyzed four independent patient cohorts with post-surgical or post-chemotherapy sepsis, chronic lymphocytic leukemia and post-surgical patients with abdominal surgical interventions. Levels of specific KSHV-encoded miRNAs were measured by reverse transcription-quantitative polymerase chain reaction (RT-qPCR, and KSHV/HHV-8 IgG were measured by immunoassay. We also measured specific miRNAs from Epstein Barr Virus (EBV, a virus closely related to KSHV/HHV-8, and determined the EBV serological status by ELISA for Epstein-Barr nuclear antigen 1 (EBNA-1 IgG. Finally, we identified the viral miRNAs by in situ hybridization (ISH in bone marrow cells. In training/validation settings using independent multi-institutional cohorts of 300 plasma samples, we identified in 78.50% of the samples detectable expression of at least one of the three tested KSHV-miRNAs by RT-qPCR, while only 27.57% of samples were found to be seropositive for KSHV/HHV-8 IgG (P < 0.001. The prevalence of KSHV infection based on miRNAs qPCR is significantly higher than the prevalence determined by seropositivity, and this is more obvious for immuno-depressed patients. Plasma viral miRNAs quantification proved that EBV infection is ubiquitous. Measurement of viral miRNAs by qPCR has the potential to become the “gold” standard method to detect certain viral infections in clinical practice.

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...

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...

A theoretically consistent stochastic cascade for temporal disaggregation of intermittent rainfall

Science.gov (United States)

Lombardo, F.; Volpi, E.; Koutsoyiannis, D.; Serinaldi, F.

2017-06-01

Generating fine-scale time series of intermittent rainfall that are fully consistent with any given coarse-scale totals is a key and open issue in many hydrological problems. We propose a stationary disaggregation method that simulates rainfall time series with given dependence structure, wet/dry probability, and marginal distribution at a target finer (lower-level) time scale, preserving full consistency with variables at a parent coarser (higher-level) time scale. We account for the intermittent character of rainfall at fine time scales by merging a discrete stochastic representation of intermittency and a continuous one of rainfall depths. This approach yields a unique and parsimonious mathematical framework providing general analytical formulations of mean, variance, and autocorrelation function (ACF) for a mixed-type stochastic process in terms of mean, variance, and ACFs of both continuous and discrete components, respectively. To achieve the full consistency between variables at finer and coarser time scales in terms of marginal distribution and coarse-scale totals, the generated lower-level series are adjusted according to a procedure that does not affect the stochastic structure implied by the original model. To assess model performance, we study rainfall process as intermittent with both independent and dependent occurrences, where dependence is quantified by the probability that two consecutive time intervals are dry. In either case, we provide analytical formulations of main statistics of our mixed-type disaggregation model and show their clear accordance with Monte Carlo simulations. An application to rainfall time series from real world is shown as a proof of concept.

Extracorporeal Membrane Oxygenation and Modern Detoxification Techniques in a Puerpera with Viral and Bacterial Pneumonia Caused by Flu A(H1N1 Virus

Directory of Open Access Journals (Sweden)

R. A. Kornelyuk

2017-01-01

Full Text Available Outbreaks of viral infections have become a global healthcare challenge over the last decade. The 2009—2010 flu A (H1N1 outbreak resulted in global pandemia, associated with high morbidity and mortality reaching 31%. Another flu A (H1N1 outbreak occurred in 2015—2016. There is a strong probability that it may be repeated in the future. This infection is associated with its high incidence among pregnant women. There are some published reports describing the efficacy and safety of veno%venous extracorporeal membrane oxygenation (ECMO in patients with severe acute respiratory distress syndrome that is refractory to standard therapeutic options. The article presents a clinical case of a successful use of extracorporeal membrane oxygenation and intermittent renal replacement therapy in a puerpera with acute respiratory distress syndrome caused by flu A (H1N1-related severe viral and bacterial pneumonia. The positive effects of the combination of veno%venous extracorporeal membrane oxygenation and modern detoxification techniques have been demonstrated. Revealed organizational problemswere related to selection criteria for prescription of extracorporeal gas exchange, as well as to carrying out the procedure in an institution in the deficiency of the experienced staff and corresponding equipment.

Wastewater viral community

Data.gov (United States)

U.S. Environmental Protection Agency — The dataset contains the information used to generate the figures in the manuscript. The data describes the viral loss measured at all steps of sample processing,...

29 CFR 825.205 - Increments of FMLA leave for intermittent or reduced schedule leave.

Science.gov (United States)

2010-07-01

... intermittent leave or working a reduced leave schedule to commence or end work mid-way through a shift, such as... per week, but works only 20 hours a week under a reduced leave schedule, the employee's ten hours of... 29 Labor 3 2010-07-01 2010-07-01 false Increments of FMLA leave for intermittent or reduced...

Acute interstitial nephritis induced by intermittent use of Rifampicin in patient with Brucellosis

International Nuclear Information System (INIS)

Salih, S. Bin; Kharal, M.; Qahtani, M.; Dahneem, L.; Nohair, S.

2008-01-01

Acute oliguric renal failure (ARF) developed in a patient 2 days after she was started on intermittent anti-Brucella therapy including rifampicin. The clinical picture was compatible with acute allergic interstitial nephritis. Renal histology revealed mainly acute tubular necrosis with mild tubulo-intertitial mononuclear cellular infiltrate. Intermittent therapy, as in our patient, has been the major factor in the development of rifampicin induced ARF in cases reviewed in literature. (author)

Observation of intermittent transition by electrode biasing in Heliotron J

International Nuclear Information System (INIS)

Shimizu, Kosuke; Kitajima, Sumio; Okamoto, Atsushi

2015-01-01

We observed intermittent increases in the electrode current in electrode biasing experiments in Heliotron J. In addition, electron density and floating potential showed pulsating behavior associated with the electrode current. The relation between line density and electrode current and that between floating potential and electrode current showed a hysteresis feature in transitions. Then it is evident that the pulsating behavior was the intermittent transition between two distinctive states. We also observed the mode (∼10 kHz) that accompanied the pulsating behavior in the power spectrum density of the floating potential and ion saturation current obtained via fast Fourier transform. The electron density gradient increased, and subsequently the power spectrum density of the fluctuation increased. (author)

Viral Advertising: Branding Effects from Consumers’ Perspectives

OpenAIRE

Jiang, Yueqing

2012-01-01

Viral advertising is popular for its high viral transmission results online. Its increased impacts on the social media users have been noticed by the author. At the same time, viewers’ negative attitudes toward traditional advertisements become obvious which can be regarded as the phenomenon of advertisement avoidance. It arouses author’s interests to know how the viral advertising reduces the viewers’ negative emotions and its performances in branding online. This paper is going to look into...

Positive effects of intermittent fasting in ischemic stroke.

Science.gov (United States)

Fann, David Yang-Wei; Ng, Gavin Yong Quan; Poh, Luting; Arumugam, Thiruma V

2017-03-01

Intermittent fasting (IF) is a dietary protocol where energy restriction is induced by alternate periods of ad libitum feeding and fasting. Prophylactic intermittent fasting has been shown to extend lifespan and attenuate the progress and severity of age-related diseases such as cardiovascular (e.g. stroke and myocardial infarction), neurodegenerative (e.g. Alzheimer's disease and Parkinson's disease) and cancerous diseases in animal models. Stroke is the second leading cause of death, and lifestyle risk factors such as obesity and physical inactivity have been associated with elevated risks of stroke in humans. Recent studies have shown that prophylactic IF may mitigate tissue damage and neurological deficit following ischemic stroke by a mechanism(s) involving suppression of excitotoxicity, oxidative stress, inflammation and cell death pathways in animal stroke models. This review summarizes data supporting the potential hormesis mechanisms of prophylactic IF in animal models, and with a focus on findings from animal studies of prophylactic IF in stroke in our laboratory. Copyright © 2017 Elsevier Inc. All rights reserved.

Elastically driven intermittent microscopic dynamics in soft solids

Science.gov (United States)

Bouzid, Mehdi; Colombo, Jader; Barbosa, Lucas Vieira; Del Gado, Emanuela

2017-06-01

Soft solids with tunable mechanical response are at the core of new material technologies, but a crucial limit for applications is their progressive aging over time, which dramatically affects their functionalities. The generally accepted paradigm is that such aging is gradual and its origin is in slower than exponential microscopic dynamics, akin to the ones in supercooled liquids or glasses. Nevertheless, time- and space-resolved measurements have provided contrasting evidence: dynamics faster than exponential, intermittency and abrupt structural changes. Here we use 3D computer simulations of a microscopic model to reveal that the timescales governing stress relaxation, respectively, through thermal fluctuations and elastic recovery are key for the aging dynamics. When thermal fluctuations are too weak, stress heterogeneities frozen-in upon solidification can still partially relax through elastically driven fluctuations. Such fluctuations are intermittent, because of strong correlations that persist over the timescale of experiments or simulations, leading to faster than exponential dynamics.

Intermittency and correlations in hadronic $Z^0$ decays

CERN Document Server

Abbiendi, G.; Alexander, G.; Allison, John; Altekamp, N.; Anderson, K.J.; Anderson, S.; Arcelli, S.; Asai, S.; Ashby, S.F.; Axen, D.; Azuelos, G.; Ball, A.H.; Barberio, E.; Barlow, Roger J.; Batley, J.R.; Baumann, S.; Bechtluft, J.; Behnke, T.; Bell, Kenneth Watson; Bella, G.; Bellerive, A.; Bentvelsen, S.; Bethke, S.; Betts, S.; Biebel, O.; Biguzzi, A.; Blobel, V.; Bloodworth, I.J.; Bock, P.; Bohme, J.; Bonacorsi, D.; Boutemeur, M.; Braibant, S.; Bright-Thomas, P.; Brigliadori, L.; Brown, Robert M.; Burckhart, H.J.; Capiluppi, P.; Carnegie, R.K.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, David G.; Chrisman, D.; Ciocca, C.; Clarke, P.E.L.; Clay, E.; Cohen, I.; Conboy, J.E.; Cooke, O.C.; Couyoumtzelis, C.; Coxe, R.L.; Cuffiani, M.; Dado, S.; Dallavalle, G.Marco; Davis, R.; De Jong, S.; de Roeck, A.; Dervan, P.; Desch, K.; Dienes, B.; Dixit, M.S.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Estabrooks, P.G.; Etzion, E.; Fabbri, F.; Fanfani, A.; Fanti, M.; Faust, A.A.; Fiedler, F.; Fierro, M.; Fleck, I.; Folman, R.; Frey, A.; Furtjes, A.; Futyan, D.I.; Gagnon, P.; Gary, J.W.; Gascon, J.; Gascon-Shotkin, S.M.; Gaycken, G.; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Gibson, V.; Gibson, W.R.; Gingrich, D.M.; Glenzinski, D.; Goldberg, J.; Gorn, W.; Grandi, C.; Graham, K.; Gross, E.; Grunhaus, J.; Gruwe, M.; Hanson, G.G.; Hansroul, M.; Hapke, M.; Harder, K.; Harel, A.; Hargrove, C.K.; Hauschild, M.; Hawkes, C.M.; Hawkings, R.; Hemingway, R.J.; Herndon, M.; Herten, G.; Heuer, R.D.; Hildreth, M.D.; Hill, J.C.; Hobson, P.R.; Hoch, M.; Hocker, James Andrew; Hoffman, Kara Dion; Homer, R.J.; Honma, A.K.; Horvath, D.; Hossain, K.R.; Howard, R.; Huntemeyer, P.; Igo-Kemenes, P.; Imrie, D.C.; Ishii, K.; Jacob, F.R.; Jawahery, A.; Jeremie, H.; Jimack, M.; Jones, C.R.; Jovanovic, P.; Junk, T.R.; Kanzaki, J.; Karlen, D.; Kartvelishvili, V.; Kawagoe, K.; Kawamoto, T.; Kayal, P.I.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Kim, D.H.; Klier, A.; Kobayashi, T.; Kobel, M.; Kokott, T.P.; Kolrep, M.; Komamiya, S.; Kowalewski, Robert V.; Kress, T.; Krieger, P.; von Krogh, J.; Kuhl, T.; Kyberd, P.; Lafferty, G.D.; Landsman, H.; Lanske, D.; Lauber, J.; Lautenschlager, S.R.; Lawson, I.; Layter, J.G.; Lazic, D.; Lee, A.M.; Lellouch, D.; Letts, J.; Levinson, L.; Liebisch, R.; List, B.; Littlewood, C.; Lloyd, A.W.; Lloyd, S.L.; Loebinger, F.K.; Long, G.D.; Losty, M.J.; Lu, J.; Ludwig, J.; Lui, D.; Macchiolo, A.; Macpherson, A.; Mader, W.; Mannelli, M.; Marcellini, S.; Markopoulos, C.; Martin, A.J.; Martin, J.P.; Martinez, G.; Mashimo, T.; Mattig, Peter; McDonald, W.John; McKenna, J.; Mckigney, E.A.; McMahon, T.J.; McPherson, R.A.; Meijers, F.; Menke, S.; Merritt, F.S.; Mes, H.; Meyer, J.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D.J.; Mir, R.; Mohr, W.; Montanari, A.; Mori, T.; Nagai, K.; Nakamura, I.; Neal, H.A.; Nisius, R.; O'Neale, S.W.; Oakham, F.G.; Odorici, F.; Ogren, H.O.; Oreglia, M.J.; Orito, S.; Palinkas, J.; Pasztor, G.; Pater, J.R.; Patrick, G.N.; Patt, J.; Perez-Ochoa, R.; Petzold, S.; Pfeifenschneider, P.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Poffenberger, P.; Poli, B.; Polok, J.; Przybycien, M.; Rembser, C.; Rick, H.; Robertson, S.; Robins, S.A.; Rodning, N.; Roney, J.M.; Rosati, S.; Roscoe, K.; Rossi, A.M.; Rozen, Y.; Runge, K.; Runolfsson, O.; Rust, D.R.; Sachs, K.; Saeki, T.; Sahr, O.; Sang, W.M.; Sarkisian, E.K.G.; Sbarra, C.; Schaile, A.D.; Schaile, O.; Scharff-Hansen, P.; Schieck, J.; Schmitt, S.; Schoning, A.; Schroder, Matthias; Schumacher, M.; Schwick, C.; Scott, W.G.; Seuster, R.; Shears, T.G.; Shen, B.C.; Shepherd-Themistocleous, C.H.; Sherwood, P.; Siroli, G.P.; Sittler, A.; Skuja, A.; Smith, A.M.; Snow, G.A.; Sobie, R.; Soldner-Rembold, S.; Spagnolo, S.; Sproston, M.; Stahl, A.; Stephens, K.; Steuerer, J.; Stoll, K.; Strom, David M.; Strohmer, R.; Surrow, B.; Talbot, S.D.; Taras, P.; Tarem, S.; Teuscher, R.; Thiergen, M.; Thomas, J.; Thomson, M.A.; Torrence, E.; Towers, S.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turcot, A.S.; Turner-Watson, M.F.; Ueda, I.; Van Kooten, Rick J.; Vannerem, P.; Verzocchi, M.; Voss, H.; Wackerle, F.; Wagner, A.; Ward, C.P.; Ward, D.R.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wells, P.S.; Wermes, N.; White, J.S.; Wilson, G.W.; Wilson, J.A.; Wyatt, T.R.; Yamashita, S.; Yekutieli, G.; Zacek, V.; Zer-Zion, D.

1999-01-01

A multidimensional study of local multiplicity fluctuations and multiparticle correlations of hadrons produced in Z decays is performed. The study is based on the data sample of more than 4 million events recorded with the OPAL detector at LEP. The fluctuations and correlations are analysed in terms of the normalized scaled factorial moments and cumulants up to the fifth order. The moments are observed to have intermittency-like behaviour, which is found to be more pronounced with increasing dimension. The large data sample allows for the first time a study of the factorial cumulants in e+e- annihilation. The analysis of the cumulants shows the existence of genuine multiparticle correlations with a strong intermittency rise up to higher orders. These correlations are found to be stronger in higher dimensions. The decomposition of the factorial moments into lower-order correlations that the dynamical fluctuations have important contributions from genuine many-particle correlations. The Monte Carlo models JETSE...

Intermittent bursts induced by double tearing mode reconnection

Science.gov (United States)

Wei, Lai; Wang, Zheng-Xiong

2014-06-01

Reversed magnetic shear (RMS) configuration is assumed to be the steady-state operation scenario for the future advanced tokamaks like International Thermonuclear Experimental Reactor. In this work, we numerically discover a phenomenon of violent intermittent bursts induced by self-organized double tearing mode (DTM) reconnection in the RMS configuration during the very long evolution, which may continuously lead to annular sawtooth crashes and thus badly impact the desired steady-state operation of the future advanced RMS tokamaks. The key process of the intermittent bursts in the off-axis region is similar to that of the typical sawtooth relaxation oscillation in the positive magnetic shear configuration. It is interestingly found that in the decay phase of the DTM reconnection, the zonal field significantly counteracts equilibrium field to make the magnetic shear between the two rational surfaces so weak that the residual self-generated vortices of the previous DTM burst are able to trigger a reverse DTM reconnection by curling the field lines.

Intermittent bursts induced by double tearing mode reconnection

International Nuclear Information System (INIS)

Wei, Lai; Wang, Zheng-Xiong

2014-01-01

Reversed magnetic shear (RMS) configuration is assumed to be the steady-state operation scenario for the future advanced tokamaks like International Thermonuclear Experimental Reactor. In this work, we numerically discover a phenomenon of violent intermittent bursts induced by self-organized double tearing mode (DTM) reconnection in the RMS configuration during the very long evolution, which may continuously lead to annular sawtooth crashes and thus badly impact the desired steady-state operation of the future advanced RMS tokamaks. The key process of the intermittent bursts in the off-axis region is similar to that of the typical sawtooth relaxation oscillation in the positive magnetic shear configuration. It is interestingly found that in the decay phase of the DTM reconnection, the zonal field significantly counteracts equilibrium field to make the magnetic shear between the two rational surfaces so weak that the residual self-generated vortices of the previous DTM burst are able to trigger a reverse DTM reconnection by curling the field lines

Intermittent bursts induced by double tearing mode reconnection

Energy Technology Data Exchange (ETDEWEB)

Wei, Lai; Wang, Zheng-Xiong, E-mail: zxwang@dlut.edu.cn [Key Laboratory of Materials Modification by Beams of the Ministry of Education, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

2014-06-15

Reversed magnetic shear (RMS) configuration is assumed to be the steady-state operation scenario for the future advanced tokamaks like International Thermonuclear Experimental Reactor. In this work, we numerically discover a phenomenon of violent intermittent bursts induced by self-organized double tearing mode (DTM) reconnection in the RMS configuration during the very long evolution, which may continuously lead to annular sawtooth crashes and thus badly impact the desired steady-state operation of the future advanced RMS tokamaks. The key process of the intermittent bursts in the off-axis region is similar to that of the typical sawtooth relaxation oscillation in the positive magnetic shear configuration. It is interestingly found that in the decay phase of the DTM reconnection, the zonal field significantly counteracts equilibrium field to make the magnetic shear between the two rational surfaces so weak that the residual self-generated vortices of the previous DTM burst are able to trigger a reverse DTM reconnection by curling the field lines.

Low nitrous oxide production in intermittent-feed high performance nitritating reactors

DEFF Research Database (Denmark)

Su, Qingxian; Jensen, Malene M.; Smets, Barth F.

Nitrous oxide (N2O) production from autotrophic nitrogen removal processes, especially nitritating systems, is of growing concern. N2O dynamics were characterized and N2O production factors were quantified in two lab-scale intermittent-feed nitritating SBRs. 93 ± 14% of the oxidized ammonium...... was converted to nitrite, with the average total net N2O production of 2.1 ± 0.7% of the ammonium oxidized. Operation with intermittent feeding appears an effective optimization approach to mitigate N2O emissions from nitritating systems. Net N2O production rates transiently increased with a rise in pH after...

Recycling Endosomes and Viral Infection.

Science.gov (United States)

Vale-Costa, Sílvia; Amorim, Maria João

2016-03-08

Many viruses exploit specific arms of the endomembrane system. The unique composition of each arm prompts the development of remarkably specific interactions between viruses and sub-organelles. This review focuses on the viral-host interactions occurring on the endocytic recycling compartment (ERC), and mediated by its regulatory Ras-related in brain (Rab) GTPase Rab11. This protein regulates trafficking from the ERC and the trans-Golgi network to the plasma membrane. Such transport comprises intricate networks of proteins/lipids operating sequentially from the membrane of origin up to the cell surface. Rab11 is also emerging as a critical factor in an increasing number of infections by major animal viruses, including pathogens that provoke human disease. Understanding the interplay between the ERC and viruses is a milestone in human health. Rab11 has been associated with several steps of the viral lifecycles by unclear processes that use sophisticated diversified host machinery. For this reason, we first explore the state-of-the-art on processes regulating membrane composition and trafficking. Subsequently, this review outlines viral interactions with the ERC, highlighting current knowledge on viral-host binding partners. Finally, using examples from the few mechanistic studies available we emphasize how ERC functions are adjusted during infection to remodel cytoskeleton dynamics, innate immunity and membrane composition.

Beyond viral suppression of HIV

DEFF Research Database (Denmark)

Lazarus, Jeffrey V.; Safreed-Harmon, Kelly; Barton, Simon E

2016-01-01

BACKGROUND: In 2016, the World Health Organization (WHO) adopted a new Global Health Sector Strategy on HIV for 2016-2021. It establishes 15 ambitious targets, including the '90-90-90' target calling on health systems to reduce under-diagnosis of HIV, treat a greater number of those diagnosed......, and ensure that those being treated achieve viral suppression. DISCUSSION: The WHO strategy calls for person-centered chronic care for people living with HIV (PLHIV), implicitly acknowledging that viral suppression is not the ultimate goal of treatment. However, it stops short of providing an explicit target...... for health-related quality of life. It thus fails to take into account the needs of PLHIV who have achieved viral suppression but still must contend with other intense challenges such as serious non-communicable diseases, depression, anxiety, financial stress, and experiences of or apprehension about HIV...

Sensitivity of intermittent streams to climate variations in the USA

Science.gov (United States)

Eng, Kenny; Wolock, David M.; Dettinger, Mike

2015-01-01

There is a great deal of interest in the literature on streamflow changes caused by climate change because of the potential negative effects on aquatic biota and water supplies. Most previous studies have primarily focused on perennial streams, and there have been only a few studies examining the effect of climate variability on intermittent streams. Our objectives in this study were to (1) identify regions of similar zero-flow behavior, and (2) evaluate the sensitivity of intermittent streams to historical variability in climate in the United States. This study was carried out at 265 intermittent streams by evaluating: (1) correlations among time series of flow metrics (number of zero-flow events, the average of the central 50% and largest 10% of flows) with climate (magnitudes, durations and intensity), and (2) decadal changes in the seasonality and long-term trends of these flow metrics. Results identified five distinct seasonality patterns in the zero-flow events. In addition, strong associations between the low-flow metrics and historical changes in climate were found. The decadal analysis suggested no significant seasonal shifts or decade-to-decade trends in the low-flow metrics. The lack of trends or changes in seasonality is likely due to unchanged long-term patterns in precipitation over the time period examined.

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

Microbiological diagnostics of viral hepatitis

OpenAIRE

HASDEMİR, Ufuk

2016-01-01

Viral hepatitis is an infection that primarily affects the liverbut may also have systemic clinical manifestations. The vastmajority of viral hepatitis are caused by one of five hepatotropicviruses: hepatitis A virus (HAV), hepatitis B virus (HBV),hepatitis C virus (HCV), hepatitis D (delta) virus (HDV), andhepatitis E virus (HEV) (Table I) [1]. HBV, HCV, and HDValso cause chronic hepatitis, whereas HAV does not. HEVcauses acute hepatitis in normal hosts but can cause protractedand chronic he...

Valuable Virality

NARCIS (Netherlands)

Akpinar, E.; Berger, Jonah

2017-01-01

Given recent interest in social media, many brands now create content that they hope consumers will view and share with peers. While some campaigns indeed go “viral,” their value to the brand is limited if they do not boost brand evaluation or increase purchase. Consequently, a key question is how

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.

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.

Therapeutic Efficacy of Intermittent Cryotherapy in the Management ...

African Journals Online (AJOL)

This study was therefore, designed to investigate the efficacy of intermittent cryotherapy in the management of pain among human subjects who sustained closed soft tissue injuries (CSTIs). Subjects' pre- and post-treatment pain perception scores (PPS) using visual analogue scale (VAS) and the sessions of treatment were ...

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 ...

Clan structure as a source of intermittency in high energy multihadron production

International Nuclear Information System (INIS)

Hove, L. van

1989-01-01

Recently the systematic study of charged hadron multiplicity distributions in high energy hadronic and leptonic collisions has revealed the general occurrence of negative binomial regularities in symmetric CM rapidity windows and of intermittency in very small windows in the central region. The negative binomial regularities imply a particular form of clustering called clan structure, which embodies all Mueller multiparticle correlations. We show that this clan structure leads to intermittency when the simplest assumptions are made on the behaviour of the clans in very small windows. (orig.)

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

Accommodative spasm with bilateral vision loss due to untreated intermittent exotropia in an adult.

Science.gov (United States)

Shanker, V; Ganesh, S; Sethi, S

2012-01-01

Intermittent exotropia (IXT) is an exodeviation intermittently controlled by fusional mechanisms. Patients with IXT may present with asthenopic symptoms, blurred vision, headaches, diplopia or visual confusion and reading difficulties; especially after prolonged periods of near work. To report the presentation and management of a young adult with intractable accommodative spasm secondary to long standing intermittent exotropia. The patient was found to have bilateral accommodative spasm with high pseudomyopia and severe impairment of vision. There was a tendency for recurrence with discontinuation of cycloplegics. A total relief of symptoms was noticed after strabismus surgery was undertaken for the exotropia. A detailed orthoptic evaluation with emphasis on recognizing accommodative spasm as an unusual presentation of IXT, could aid in appropriate diagnosis and treatment of such cases. © NEPjOPH.

An integrated approach to elucidate the intra-viral and viral-cellular protein interaction networks of a gamma-herpesvirus.

Directory of Open Access Journals (Sweden)

Shaoying Lee

2011-10-01

Full Text Available Genome-wide yeast two-hybrid (Y2H screens were conducted to elucidate the molecular functions of open reading frames (ORFs encoded by murine γ-herpesvirus 68 (MHV-68. A library of 84 MHV-68 genes and gene fragments was generated in a Gateway entry plasmid and transferred to Y2H vectors. All possible pair-wise interactions between viral proteins were tested in the Y2H assay, resulting in the identification of 23 intra-viral protein-protein interactions (PPIs. Seventy percent of the interactions between viral proteins were confirmed by co-immunoprecipitation experiments. To systematically investigate virus-cellular protein interactions, the MHV-68 Y2H constructs were screened against a cellular cDNA library, yielding 243 viral-cellular PPIs involving 197 distinct cellar proteins. Network analyses indicated that cellular proteins targeted by MHV-68 had more partners in the cellular PPI network and were located closer to each other than expected by chance. Taking advantage of this observation, we scored the cellular proteins based on their network distances from other MHV-68-interacting proteins and segregated them into high (Y2H-HP and low priority/not-scored (Y2H-LP/NS groups. Significantly more genes from Y2H-HP altered MHV-68 replication when their expression was inhibited with siRNAs (53% of genes from Y2H-HP, 21% of genes from Y2H-LP/NS, and 16% of genes randomly chosen from the human PPI network; p<0.05. Enriched Gene Ontology (GO terms in the Y2H-HP group included regulation of apoptosis, protein kinase cascade, post-translational protein modification, transcription from RNA polymerase II promoter, and IκB kinase/NFκB cascade. Functional validation assays indicated that PCBP1, which interacted with MHV-68 ORF34, may be involved in regulating late virus gene expression in a manner consistent with the effects of its viral interacting partner. Our study integrated Y2H screening with multiple functional validation approaches to create �

Noise-sustained structure, Intermittency, and the Ginzburg--Landau equation

International Nuclear Information System (INIS)

Deissler, R.J.

1985-01-01

The time-dependent generalized Ginzburg--Landau equation is an equation that is related to many physical systems. Solutions of this equation in the presence of low-level external noise are studied. Numerical solutions of this equation in the stationary frame of refernce and with nonzero group velocity that is greater than a critical velocity exhibit a selective spatial amplification of noise resulting in spatially growing waves. These waves in turn result in the formation of a dynamic structure. It is found that the microscopic noise plays an importuant role in the macroscopic dynamics of the system. For certain parameter values the system exhibits intermittent turbulent behavior in which the random nature of the external noise plays a crucial role. A mechanism which may be responsible for the intermittent turbulence occurring in some fluid systems is suggested

The organ specificity in pathological damage of chronic intermittent hypoxia: an experimental study on rat with high-fat diet.

Science.gov (United States)

Wang, Hui; Tian, Jian-li; Feng, Shu-zhi; Sun, Ning; Chen, Bao-yuan; Zhang, Yun

2013-09-01

It is known today that sleep apnea hypopnea syndrome and its characteristic chronic intermittent hypoxia can cause damages to multiple organs, including the cardiovascular system, urinary system, and liver. It is still unclear, however, whether the damage caused by sleep apnea hypopnea syndrome and the severity of the damage are organ-specific. This research observed the pathological effects of chronic intermittent hypoxia on rat's thoracic aorta, myocardium, liver, and kidney, under the condition of lipid metabolism disturbance, through establishing the rat model of chronic intermittent hypoxia with high-fat diet by imitating the features of human sleep apnea hypopnea syndrome. In this model, 24 male Wistar rats were randomly divided into three groups: a control group fed by regular diet, a high-fat group fed by high-fat diet, and a high-fat plus intermittent hypoxia group fed by high-fat diet and treated with intermittent hypoxia 7 h a day. At the end of the ninth week, the pathological changes of rat's organs, including the thoracic aorta, myocardium, liver, and kidney are observed (under both optical microscopy and transmission electron microscopy). As the result of the experiment shows, while there was no abnormal effect observed on any organs of the control group, slight pathological changes were found in the organs of the high-fat group. For the high-fat plus intermittent hypoxia group, however, remarkably severer damages were found on all the organs. It also showed that the severity of the damage varies by organ in the high-fat plus intermittent hypoxia group, with the thoracic aorta being the worst, followed by the liver and myocardium, and the kidney being the slightest. Chronic intermittent hypoxia can lead to multiple-organ damage to rat with high-fat diet. Different organs appear to have different sensitivity to chronic intermittent hypoxia.

A novel inclusion of intermittent generation resources in long term energy auctions

International Nuclear Information System (INIS)

Marambio, Rodrigo; Rudnick, Hugh

2017-01-01

Long term energy auctions are positioning as a valuable tool in order to attract new investments into power systems, especially in Latin American countries where emergent economies characteristics and their correspondent risks are usually present. Even though the focus of these auctions is the long term, there are short term issues involved which actual auction designs fail to include, resulting in an energy allocation that is not necessarily optimal for the system, a condition which becomes more evident in the presence of intermittent renewable technologies. A novel mechanism is formulated to obtain the optimal allocation in long term energy auctions, considering short term generation profiles from both intermittent and conventional base load technologies, and also their risk aversions. The proposed mechanism is developed and simulations are made for some scenarios in the Chilean power market, with different levels of renewable penetration. Significant cost savings are achieved for the final consumers in relation to energy purchases, in comparison with a mechanism that follows the demand profile. As more renewable intermittent capacity enters the power system it is evident the need for changes in the energy auctions allocation mechanisms, including elements to exploit the synergies among participants in the short term. - Highlights: • Risk management consideration in technology neutral auctions allocation. • Allocation mechanism in technology neutral auctions with intermittent technologies. • Renewable and conventional technologies energy auction offer curves. • Increase bid prices in auctions as a consequence of solar technology support.

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.

Intermittency in super-high energy cosmic ray events

International Nuclear Information System (INIS)

Gladysz-Dziadus, E.

1988-12-01

The factorial moments method described by Bialas and Peschanski was used for investigations of fluctuations in pseudorapidity distributions of nine cosmic-ray events at energy of about 1000 TeV. Both electromagnetic and hadronic components of these events reveal very strong intermittent behaviour. 8 refs., 7 figs., 2 tabs. (author)

Mast cells in viral infections

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Piotr Witczak

2012-04-01

Full Text Available  There are some premises suggesting that mast cells are involved in the mechanisms of anti-virus defense and in viral disease pathomechanisms. Mast cells are particularly numerous at the portals of infections and thus may have immediate and easy contact with the external environment and invading pathogens. These cells express receptors responsible for recognition of virus-derived PAMP molecules, mainly Toll-like receptors (TLR3, TLR7/8 and TLR9, but also RIG-I-like and NOD-like molecules. Furthermore, mast cells generate various mediators, cytokines and chemokines which modulate the intensity of inflammation and regulate the course of innate and adaptive anti-viral immunity. Indirect evidence for the role of mast cells in viral infections is also provided by clinical observations and results of animal studies. Currently, more and more data indicate that mast cells can be infected by some viruses (dengue virus, adenoviruses, hantaviruses, cytomegaloviruses, reoviruses, HIV-1 virus. It is also demonstrated that mast cells can release pre formed mediators as well as synthesize de novo eicosanoids in response to stimulation by viruses. Several data indicate that virus-stimulated mast cells secrete cytokines and chemokines, including interferons as well as chemokines with a key role in NK and Tc lymphocyte influx. Moreover, some information indicates that mast cell stimulation via TLR3, TLR7/8 and TLR9 can affect their adhesion to extracellular matrix proteins and chemotaxis, and influence expression of some membrane molecules. Critical analysis of current data leads to the conclusion that it is not yet possible to make definitive statements about the role of mast cells in innate and acquired defense mechanisms developing in the course of viral infection and/or pathomechanisms of viral diseases.

Intermittency of gravity wave momentum flux in the mesopause region observed with an all-sky airglow imager

Science.gov (United States)

Cao, Bing; Liu, Alan Z.

2016-01-01

The intermittency of gravity wave momentum flux (MF) near the OH airglow layer (˜87 km) in the mesopause region is investigated for the first time using observation of all-sky airglow imager over Maui, Hawaii (20.7°N, 156.3°W), and Cerro Pachón, Chile (30.3°S, 70.7°W). At both sites, the probability density function (pdf) of gravity wave MF shows two distinct distributions depending on the magnitude of the MF. For MF smaller (larger) than ˜16 m2 s-2 (0.091 mPa), the pdf follows a lognormal (power law) distribution. The intermittency represented by the Bernoulli proxy and the percentile ratio shows that gravity waves have higher intermittency at Maui than at Cerro Pachón, suggesting more intermittent background variation above Maui. It is found that most of the MF is contributed by waves that occur very infrequently. But waves that individually contribute little MF are also important because of their higher occurrence frequencies. The peak contribution is from waves with MF around ˜2.2 m2 s-2 at Cerro Pachón and ˜5.5 m2 s-2 at Maui. Seasonal variations of the pdf and intermittency imply that the background atmosphere has larger influence on the observed intermittency in the mesopause region.

Surveillance for Viral Hepatitis - United States, 2014

Science.gov (United States)

... Resource Center Anonymous Feedback Viral Hepatitis Surveillance for Viral Hepatitis – United States, 2014 Recommend on Facebook Tweet Share ... Cases Hepatitis A Hepatitis B Hepatitis C Discussion Hepatitis A virus Index PAGE DESCRIPTION Table 2.1 Reported ...

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.

Network Capacity Assessment and Increase in Systems with Intermittent Water Supply

Directory of Open Access Journals (Sweden)

Amilkar E. Ilaya-Ayza

2016-03-01

Full Text Available Water supply systems have been facing many challenges in recent decades due to the potential effects of climate change and rapid population growth. Water systems need to expand because of demographic growth. Therefore, evaluating and increasing system capacity is crucial. Specifically, we analyze network capacity as one of the main features of a system. When the network capacity starts to decrease, there is a risk that continuous supply will become intermittent. This paper discusses how network expansion carried out throughout the network life span typically reduces network capacity, thus transforming a system originally designed to work with continuous supply into a system with intermittent supply. A method is proposed to expand the network capacity in an environment of economic scarcity through a greedy algorithm that enables the definition of a schedule for pipe modification stages, and thus efficiently expands the network capacity. This method is, at the same time, an important step in the process of changing a water system from intermittent back to continuous supply—an achievement that remains one of the main challenges related to water and health in developing countries.

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.

Continuous use of intermittent bladder catheterization - can social support contribute?

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Marjoyre Anne Lindozo Lopes

2014-06-01

Full Text Available OBJECTIVE: to investigate the factors affecting the adequate continuous use of intermittent catheterization and its relation with social support.METHOD: sectional, descriptive and correlational study involving 49 patients with neuropathic bladder caused by spinal cord injury.RESULTS: almost all (92% participants continued the intermittent catheterization, but 46.9% made some changes in the technique. The complications (28.6% of the sample were mainly infection and vesicolithiasis. There were high scores for social support in relation to people that were part of the patient's social support.CONCLUSION: All of them noticed great support from the family, but not from the society in general. The difficulties were related to the lack of equipment and inadequate infrastructure, leading to changes that increased urologic complications.

Intermittency study in e+e- annihilations at 29 GeV

International Nuclear Information System (INIS)

Sugano, K.

1990-01-01

The intermittency and fractal behavior in e + e - annihilations has been studied using the HRS detector at PEP (√s = 29 GeV). The factorial moments F i (i = 2 ∼ 5) in small rapidity intervals show stronger intermittency slopes than those for the πp, bar pp, and AA reactions. This direct measurement confirms our previous data derived from the k-values in the negative binomial fits to the multiplicity distributions in various central rapidity windows. The fractal moments G q have been measured for the first time in e + e - annihilations. The Legendre transform f(α) derived from the fractal moments show a self-similar behavior which is consistent with the jet cascading mechanism. 95 refs., 46 figs., 2 tabs

Biomonitoring of intermittent rivers and ephemeral streams in Europe

NARCIS (Netherlands)

Stubbington, Rachel; Chadd, Richard; Cid, Núria; Csabai, Zoltán; Miliša, Marko; Morais, Manuela; Munné, Antoni; Pařil, Petr; Pešić, Vladimir; Tziortzis, Iakovos; Verdonschot, Ralf C.M.; Datry, Thibault

2018-01-01

Intermittent rivers and ephemeral streams (IRES) are common across Europe and dominate some Mediterranean river networks. In all climate zones, IRES support high biodiversity and provide ecosystem services. As dynamic ecosystems that transition between flowing, pool, and dry states, IRES are

Intermittency in delay-coupled FitzHugh–Nagumo oscillators and ...

Indian Academy of Sciences (India)

We study the dynamical properties of in-out intermittency in a system of two ... interest has also been exhibited in the field of multi- .... Color code: small amplitude oscillations in green, .... Zoomed-in view of a typical time series showing.

On the effect of intermittency of turbulence on the parabolic relation between skewness and kurtosis in magnetized plasmas

Energy Technology Data Exchange (ETDEWEB)

Guszejnov, Dávid; Lazányi, Nóra [Department of Nuclear Techniques, Budapest University of Technology and Economics, Association EURATOM, Műegyetem rkp. 9., H-1111 Budapest (Hungary); Bencze, Attila; Zoletnik, Sándor [MTA Wigner RCP, EURATOM Association, PO Box 49, H-1525 Budapest (Hungary)

2013-11-15

This paper is aimed to contribute to the scientific discussions that have been triggered by the experimental observation of a quadratic relation between the kurtosis and skewness of turbulent fluctuations present in fusion plasmas and other nonlinear physical systems. In this paper, we offer a general statistical model which attributes the observed K=aS{sup 2}+b relation to the varying intermittency of the experimental signals. The model is a two random variable model constructed to catch the essential intermittent feature of the real signal. One of the variables is the amplitude of the underlying intermittent event (e.g., turbulent structure) while the other is connected to the intermittency level of the system. This simple model can attribute physical meaning to the a and b coefficients, as they characterize the spatio-temporal statistics of intermittent events. By constructing a particle-conserving Gaussian model for the underlying coherent structures, the experimentally measured a and b coefficients could be adequately reproduced.

On the effect of intermittency of turbulence on the parabolic relation between skewness and kurtosis in magnetized plasmas

International Nuclear Information System (INIS)

Guszejnov, Dávid; Lazányi, Nóra; Bencze, Attila; Zoletnik, Sándor

2013-01-01

This paper is aimed to contribute to the scientific discussions that have been triggered by the experimental observation of a quadratic relation between the kurtosis and skewness of turbulent fluctuations present in fusion plasmas and other nonlinear physical systems. In this paper, we offer a general statistical model which attributes the observed K=aS 2 +b relation to the varying intermittency of the experimental signals. The model is a two random variable model constructed to catch the essential intermittent feature of the real signal. One of the variables is the amplitude of the underlying intermittent event (e.g., turbulent structure) while the other is connected to the intermittency level of the system. This simple model can attribute physical meaning to the a and b coefficients, as they characterize the spatio-temporal statistics of intermittent events. By constructing a particle-conserving Gaussian model for the underlying coherent structures, the experimentally measured a and b coefficients could be adequately reproduced

View and review on viral oncology research

Directory of Open Access Journals (Sweden)

Parolin Cristina

2010-05-01

Full Text Available Abstract To date, almost one and a half million cases of cancer are diagnosed every year in the US and nearly 560,000 Americans are expected to die of cancer in the current year, more than 1,500 people a day (data from the American Cancer Society at http://www.cancer.org/. According to the World Health Organization (WHO, roughly 20% of all cancers worldwide results from chronic infections; in particular, up to 15% of human cancers is characterized by a viral aetiology with higher incidence in Developing Countries. The link between viruses and cancer was one of the pivotal discoveries in cancer research during the past Century. Indeed, the infectious nature of specific tumors has important implications in terms of their prevention, diagnosis, and therapy. In the 21st Century, the research on viral oncology field continues to be vigorous, with new significant and original studies on viral oncogenesis and translational research from basic virology to treatment of cancer. This review will cover different viral oncology aspects, starting from the history of viral oncology and moving to the peculiar features of oncogenic RNA and DNA viruses, with a special focus on human pathogens.

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.

Recognizing Single Collisions of PtCl6(2-) at Femtomolar Concentrations on Ultramicroelectrodes by Nucleating Electrocatalytic Clusters.

Science.gov (United States)

Dick, Jeffrey E; Bard, Allen J

2015-11-04

We report the electrodeposition of electrocatalytic clusters of platinum from femtomolar platinate solutions. An inert carbon fiber ultramicroelectrode (UME) was held at a potential where proton reduction was unfavorable on carbon but favorable on platinum in a 1 M sulfuric acid solution. Upon addition of femtomolar amounts of hexachloroplatinic acid, which will also reduce to Pt(0) at the applied potential on the carbon fiber UME, cathodic blips were observed in the amperometric i-t response. These blips correspond to the reduction of protons to molecular hydrogen at the small platinum clusters followed by a rapid deactivation likely due to hydrogen bubble formation. On average, these current spikes occur when five platinum atoms have been formed on the electrode, as determined by a comparative analysis of experimental cathodic blips and calculated hexachloroplatinate molecule collision frequencies.

Sodium bicarbonate intake improves high-intensity intermittent exercise performance in trained young men

DEFF Research Database (Denmark)

Krustrup, Peter; Ermidis, Georgios; Mohr, Magni

2015-01-01

Background Sodium bicarbonate intake has been shown to improve exercise tolerance, but the effects on high-intensity intermittent exercise are less clear. Thus, the aim of the present study was to determine the effect of sodium bicarbonate intake on Yo-Yo intermittent recovery level 2 test......) prior intake of sodium bicarbonate (0.4 g · kg−1 body weight). Heart rate and rating of perceived exertion (RPE) were measured during the test and venous blood samples were taken frequently. Results Yo-Yo IR2 performance was 14 % higher (P = 0.04) in SBC than in CON (735 ± 61 vs 646 ± 46 m, respectively......-intensity intermittent exercise performance is improved by prior intake of sodium bicarbonate in trained young men, with concomitant elevations in blood alkalosis and peak blood lactate levels, as well as lowered rating of perceived exertion....

Optimizing viral and non-viral gene transfer methods for genetic modification of porcine mesenchymal stem cells

DEFF Research Database (Denmark)

Stiehler, Maik; Duch, Mogens; Mygind, Tina

2006-01-01

INTRODUCTION: Mesenchymal stem cells (MSCs) provide an excellent source of pluripotent progenitor cells for tissue-engineering applications due to their proliferation capacity and differentiation potential. Genetic modification of MSCs with genes encoding tissue-specific growth factors...... viral and non-viral ex vivo gene delivery systems with respect to gene transfer efficiency, maintenance of transgene expression, and safety issues using primary porcine MSCs as target cells. MATERIALS AND METHODS: MSCs were purified from bone marrow aspirates from the proximal tibiae of four 3-month......-old Danish landrace pigs by Ficoll step gradient separation and polystyrene adherence technique. Vectors expressing enhanced green fluorescent protein (eGFP) and human bone morphogenetic protein-2 (BMP-2) were transferred to the cells by different non-viral methods and by use of recombinant adeno...

Possible Relevance of Receptor-Receptor Interactions between Viral- and Host-Coded Receptors for Viral-Induced Disease

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Luigi F. Agnati

2007-01-01

Full Text Available It has been demonstrated that some viruses, such as the cytomegalovirus, code for G-protein coupled receptors not only to elude the immune system, but also to redirect cellular signaling in the receptor networks of the host cells. In view of the existence of receptor-receptor interactions, the hypothesis is introduced that these viral-coded receptors not only operate as constitutively active monomers, but also can affect other receptor function by interacting with receptors of the host cell. Furthermore, it is suggested that viruses could also insert not single receptors (monomers, but clusters of receptors (receptor mosaics, altering the cell metabolism in a profound way. The prevention of viral receptor-induced changes in host receptor networks may give rise to novel antiviral drugs that counteract viral-induced disease.

Reliability, validity and usefulness of 30-15 Intermittent Fitness Test in Female Soccer Players

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Nedim Čović

2016-11-01

Full Text Available PURPOSE: The aim of this study was to examine the reliability, validity and usefulness of the 30-15IFT in competitive female soccer players. METHODS: Seventeen elite female soccer players participated in the study. A within subject test-retest study design was utilized to assess the reliability of the 30-15 intermittent fitness test (IFT. Seven days prior to 30-15IFT, subjects performed a continuous aerobic running test (CT under laboratory conditions to assess the criterion validity of the 30-15IFT. End running velocity (VCT and VIFT, peak heart rate (HRpeak and maximal oxygen consumption (VO2max were collected and/or estimated for both tests. RESULTS: VIFT (ICC = 0.91; CV = 1.8%, HRpeak (ICC = 0.94; CV = 1.2%, and VO2max (ICC = 0.94; CV = 1.6% obtained from the 30-15IFT were all deemed highly reliable (p>0.05. Pearson product moment correlations between the CT and 30-15IFT for VO2max, HRpeak and end running velocity were large (r = 0.67, p=0.013, very large (r = 0.77, p=0.02 and large (r = 0.57, p=0.042, respectively. CONCLUSION: Current findings suggest that the 30 -15IFT is a valid and reliable intermittent aerobic fitness test of elite female soccer players. The findings have also provided practitioners with evidence to support the accurate detection of meaningful individual changes in VIFT of 0.5 km/h (1 stage and HRpeak of 2 bpm. This information may assist coaches in monitoring ‘real’ aerobic fitness changes to better inform training of female intermittent team sport athletes. Lastly, coaches could use the 30-15IFT as a practical alternative to laboratory based assessments to assess and monitor intermittent aerobic fitness changes in their athletes. Keywords: 30-15 intermittent fitness test, aerobic, cardiorespiratory fitness, intermittent activity, soccer, high intensity interval training.

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

Effects of flow intermittency and pharmaceutical exposure on the structure and metabolism of stream biofilms.

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Corcoll, Natàlia; Casellas, Maria; Huerta, Belinda; Guasch, Helena; Acuña, Vicenç; Rodríguez-Mozaz, Sara; Serra-Compte, Albert; Barceló, Damià; Sabater, Sergi

2015-01-15

Increasing concentrations of pharmaceutical compounds occur in many rivers, but their environmental risk remains poorly studied in stream biofilms. Flow intermittency shapes the structure and functions of ecosystems, and may enhance their sensitivity to toxicants. This study evaluates the effects of a long-term exposure of biofilm communities to a mixture of pharmaceutical compounds at environmental concentrations on biofilm bioaccumulation capacity, the structure and metabolic processes of algae and bacteria communities, and how their potential effects were enhanced or not by the occurrence of flow intermittency. To assess the interaction between those two stressors, an experiment with artificial streams was performed. Stream biofilms were exposed to a mixture of pharmaceuticals, as well as to a short period of flow intermittency. Results indicate that biofilms were negatively affected by pharmaceuticals. The algal biomass and taxa richness decreased and unicellular green algae relatively increased. The structure of the bacterial (based on denaturing gradient gel electrophoresis of amplified 16S rRNA genes) changed and showed a reduction of the operational taxonomic units (OTUs) richness. Exposed biofilms showed higher rates of metabolic processes, such as primary production and community respiration, attributed to pharmaceuticals stimulated an increase of green algae and heterotrophs, respectively. Flow intermittency modulated the effects of chemicals on natural communities. The algal community became more sensitive to short-term exposure of pharmaceuticals (lower EC50 value) when exposed to water intermittency, indicating cumulative effects between the two assessed stressors. In contrast to algae, the bacterial community became less sensitive to short-term exposure of pharmaceuticals (higher EC50) when exposed to water intermittency, indicating co-tolerance phenomena. According to the observed effects, the environmental risk of pharmaceuticals in nature is high

Impact of intermittent fasting on the lipid profile: Assessment associated with diet and weight loss.

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Santos, Heitor O; Macedo, Rodrigo C O

2018-04-01

Intermittent fasting, whose proposed benefits include the improvement of lipid profile and the body weight loss, has gained considerable scientific and popular repercussion. This review aimed to consolidate studies that analyzed the lipid profile in humans before and after intermittent fasting period through a detailed review; and to propose the physiological mechanism, considering the diet and the body weight loss. Normocaloric and hypocaloric intermittent fasting may be a dietary method to aid in the improvement of the lipid profile in healthy, obese and dyslipidemic men and women by reducing total cholesterol, LDL, triglycerides and increasing HDL levels. However, the majority of studies that analyze the intermittent fasting impacts on the lipid profile and body weight loss are observational based on Ramadan fasting, which lacks large sample and detailed information about diet. Randomized clinical trials with a larger sample size are needed to evaluate the IF effects mainly in patients with dyslipidemia. Copyright © 2018 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.

Delayed diagnosis of intermittent mesenteroaxial volvulus of the stomach by computed tomography: a case report

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Woon Colin

2008-11-01

Full Text Available Abstract Introduction Gastric volvulus is a rare condition. Presenting acutely, mesenteroaxial gastric volvulus has characteristic symptoms and may be easily detected with upper gastrointestinal contrast studies. In contrast, subacute, intermittent cases present with intermittent vague symptoms from episodic twisting and untwisting. Imaging in these cases is only useful if performed in the symptomatic interval. Case presentation We describe a patient with a long history of intermittent chest and epigastric pain. An earlier barium meal was not diagnostic. Diagnosis was finally secured during the current admission by a combination of (1 serum investigations, (2 endoscopy, and finally (3 computed tomography. Conclusion Non-specific and misleading symptoms and signs may delay the diagnosis of intermittent, subacute volvulus. Imaging studies performed in the well interval may be non-diagnostic. Elevated creatine kinase and aldolase of a non-cardiac cause and endoscopic findings of ischaemic ulceration and difficulty in negotiating the pylorus may raise the suspicion of gastric volvulus. In this case, abdominal computed tomography with spatial reconstruction was crucial in securing the final diagnosis.

Evaluation of continuous and intermittent myocardial topical negative pressure

DEFF Research Database (Denmark)

Lindstedt, Sandra; Malmsjö, Malin; Gesslein, Bodil

2008-01-01

Topical negative pressure, commonly used in wound therapy, has been shown to increase blood flow and stimulate angiogenesis in subcutaneous tissue and skeletal muscle. In wound therapy, intermittent negative pressure is often preferred to continuous negative pressure as tissue exposed to intermit...

Immunity: Insect Immune Memory Goes Viral.

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Ligoxygakis, Petros

2017-11-20

Adaptive memory in insect immunity has been controversial. In this issue, Andino and co-workers propose that acquisition of viral sequences in the host genome gives rise to anti-sense, anti-viral piRNAs. Such sequences can be regarded as both a genomic archive of past infections and as an armour of potential heritable memory. Copyright © 2017 Elsevier Ltd. All rights reserved.

Optimal Intermittent Operation of Water Distribution Networks under Water Shortage

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mohamad Solgi

2017-07-01

Full Text Available Under water shortage conditions, it is necessary to exercise water consumption management practices in water distribution networks (WDN. Intermittent supply of water is one such practice that makes it possible to supply consumption nodal demands with the required pressure via water cutoff to some consumers during certain hours of the day. One of the most important issues that must be observed in this management practice is the equitable and uniform water distribution among the consumers. In the present study, uniformity in water distribution and minimum supply of water to all consumers are defined as justice and equity, respectively. Also, an optimization model has been developed to find an optimal intermittent supply schedule that ensures maximum number of demand nodes are supplied with water while the constraints on the operation of water distribution networks are also observed. To show the efficiency of the proposed model, it has been used in the Two-Loop distribution network under several different scenarios of water shortage. The optimization model has been solved using the honey bee mating optimization algorithm (HBMO linked to the hydraulic simulator EPANET. The results obtained confirm the efficiency of the proposed model in achieving an optimal intermittent supply schedule. Moreover, the model is found capable of distributing the available water in an equitable and just manner among all the consumers even under severe water shoratges.

A highly intensified ART regimen induces long-term viral suppression and restriction of the viral reservoir in a simian AIDS model.

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Iart Luca Shytaj

Full Text Available Stably suppressed viremia during ART is essential for establishing reliable simian models for HIV/AIDS. We tested the efficacy of a multidrug ART (highly intensified ART in a wide range of viremic conditions (10³-10⁷ viral RNA copies/mL in SIVmac251-infected rhesus macaques, and its impact on the viral reservoir. Eleven macaques in the pre-AIDS stage of the disease were treated with a multidrug combination (highly intensified ART consisting of two nucleosidic/nucleotidic reverse transcriptase inhibitors (emtricitabine and tenofovir, an integrase inhibitor (raltegravir, a protease inhibitor (ritonavir-boosted darunavir and the CCR5 blocker maraviroc. All animals stably displayed viral loads below the limit of detection of the assay (i.e. <40 RNA copies/mL after starting highly intensified ART. By increasing the sensitivity of the assay to 3 RNA copies/mL, viral load was still below the limit of detection in all subjects tested. Importantly, viral DNA resulted below the assay detection limit (<2 copies of DNA/5*10⁵ cells in PBMCs and rectal biopsies of all animals at the end of the follow-up, and in lymph node biopsies from the majority of the study subjects. Moreover, highly intensified ART decreased central/transitional memory, effector memory and activated (HLA-DR⁺ effector memory CD4⁺ T-cells in vivo, in line with the role of these subsets as the main cell subpopulations harbouring the virus. Finally, treatment with highly intensified ART at viral load rebound following suspension of a previous anti-reservoir therapy eventually improved the spontaneous containment of viral load following suspension of the second therapeutic cycle, thus leading to a persistent suppression of viremia in the absence of ART. In conclusion, we show, for the first time, complete suppression of viral load by highly intensified ART and a likely associated restriction of the viral reservoir in the macaque AIDS model, making it a useful platform for testing

Optimization of continuous and intermittent microwave extraction of pectin from banana peels.

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Swamy, Gabriela John; Muthukumarappan, Kasiviswanathan

2017-04-01

Continuous and intermittent microwave-assisted extractions were used to extract pectin from banana peels. Extraction parameters which were employed in the continuous process were microwave power (300-900W), time (100-300s), pH (1-3) and in the intermittent process were microwave power (300-900W), pulse ratio (0.5-1), pH (1-3). The independent factors were optimized with the Box-Behnken response surface design (BBD) (three factor three level) with the desirability function methodology. Results indicate that the independent factors have substantial effect on the pectin yield. Optimized solutions for highest pectin yield (2.18%) from banana peels were obtained with microwave power of 900W, time 100s and pH 3.00 in the continuous method while the intermittent process yielded the highest pectin content (2.58%) at microwave power of 900W, pulse ratio of 0.5 and pH of 3.00. The optimized conditions were validated and close agreement was observed with the validation experiment and predicted value. Copyright © 2016 Elsevier Ltd. All rights reserved.

Quasi-One-Dimensional Intermittent Flux Behavior in Superconducting Films

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A. J. Qviller

2012-01-01

Full Text Available Intermittent filamentary dynamics of the vortex matter in superconductors is found in films of YBa_{2}Cu_{3}O_{7-δ} deposited on tilted substrates. Deposition of this material on such substrates creates parallel channels of easy flux penetration when a magnetic field is applied perpendicular to the film. As the applied field is gradually increased, magneto-optical imaging reveals that flux penetrates via numerous quasi-one-dimensional jumps. The distribution of flux avalanche sizes follows a power law, and data collapse is obtained by finite-size scaling, with the depth of the flux front used as crossover length. The intermittent behavior shows no threshold value in the applied field, in contrast to conventional flux jumping. The results strongly suggest that the quasi-one-dimensional flux jumps are of a different nature than the thermomagnetic dendritic (branching avalanches that are commonly found in superconducting films.

Kullback-Leibler divergence measure of intermittency: Application to turbulence

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Granero-Belinchón, Carlos; Roux, Stéphane G.; Garnier, Nicolas B.

2018-01-01

For generic systems exhibiting power law behaviors, and hence multiscale dependencies, we propose a simple tool to analyze multifractality and intermittency, after noticing that these concepts are directly related to the deformation of a probability density function from Gaussian at large scales to non-Gaussian at smaller scales. Our framework is based on information theory and uses Shannon entropy and Kullback-Leibler divergence. We provide an extensive application to three-dimensional fully developed turbulence, seen here as a paradigmatic complex system where intermittency was historically defined and the concepts of scale invariance and multifractality were extensively studied and benchmarked. We compute our quantity on experimental Eulerian velocity measurements, as well as on synthetic processes and phenomenological models of fluid turbulence. Our approach is very general and does not require any underlying model of the system, although it can probe the relevance of such a model.

Mars Atmospheric Entry Integrated Navigation with Partial Intermittent Measurements

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Tai-shan Lou

2017-01-01

Full Text Available Signal degradation suffered by the vehicle is a combination brownout and blackout during Mars atmospheric entry. The communications brownout means that signal fades and blackout means that the signal is lost completely. The communications brownout and blackout periods are analyzed and predicted with an altitude and velocity profiles. In the brownout period, the range measurements between the vehicle and the orbiters are modeled as intermittent measurements with the radio signal arrival probabilities, which are distributed as a Rayleigh distribution of the electron number density around the entry vehicle. A new integrated navigation strategy during the Mars atmospheric entry phase is proposed to consider the probabilities of the radio measurements in the communications brownout and blackout periods under the IMU/beacon scenario based on the information filter with intermittent measurements. Numerical navigation simulations are designed to show the performance of the proposed navigation strategy under the integrated navigation scenario.

A non-inferiority, individually randomized trial of intermittent screening and treatment versus intermittent preventive treatment in the control of malaria in pregnancy

DEFF Research Database (Denmark)

Tagbor, Harry; Cairns, Matthew; Bojang, Kalifa

2015-01-01

BACKGROUND: The efficacy of intermittent preventive treatment for malaria with sulfadoxine-pyrimethamine (IPTp-SP) in pregnancy is threatened in parts of Africa by the emergence and spread of resistance to SP. Intermittent screening with a rapid diagnostic test (RDT) and treatment of positive women...... with malaria parasitemia between routine antenatal clinics (310 vs 182 episodes, rate difference: 49.4 per 1,000 pregnancies [95% CI 30.5, 68.3], but the number of hospital admissions for malaria was similar in the two groups. CONCLUSIONS: Despite low levels of resistance to SP in the study areas, ISTp......-AL performed as well as IPTp-SP. In the absence of an effective alternative medication to SP for IPTp, ISTp-AL is a potential alternative to IPTp in areas where SP resistance is high. It may also have a role in areas where malaria transmission is low and for the prevention of malaria in HIV positive women...

Dissipation, intermittency, and singularities in incompressible turbulent flows

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Debue, P.; Shukla, V.; Kuzzay, D.; Faranda, D.; Saw, E.-W.; Daviaud, F.; Dubrulle, B.

2018-05-01

We examine the connection between the singularities or quasisingularities in the solutions of the incompressible Navier-Stokes equation (INSE) and the local energy transfer and dissipation, in order to explore in detail how the former contributes to the phenomenon of intermittency. We do so by analyzing the velocity fields (a) measured in the experiments on the turbulent von Kármán swirling flow at high Reynolds numbers and (b) obtained from the direct numerical simulations of the INSE at a moderate resolution. To compute the local interscale energy transfer and viscous dissipation in experimental and supporting numerical data, we use the weak solution formulation generalization of the Kármán-Howarth-Monin equation. In the presence of a singularity in the velocity field, this formulation yields a nonzero dissipation (inertial dissipation) in the limit of an infinite resolution. Moreover, at finite resolutions, it provides an expression for local interscale energy transfers down to the scale where the energy is dissipated by viscosity. In the presence of a quasisingularity that is regularized by viscosity, the formulation provides the contribution to the viscous dissipation due to the presence of the quasisingularity. Therefore, our formulation provides a concrete support to the general multifractal description of the intermittency. We present the maps and statistics of the interscale energy transfer and show that the extreme events of this transfer govern the intermittency corrections and are compatible with a refined similarity hypothesis based on this transfer. We characterize the probability distribution functions of these extreme events via generalized Pareto distribution analysis and find that the widths of the tails are compatible with a similarity of the second kind. Finally, we make a connection between the topological and the statistical properties of the extreme events of the interscale energy transfer field and its multifractal properties.

Intermittency in MHD turbulence and coronal nanoflares modelling

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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.

The proteasomal Rpn11 metalloprotease suppresses tombusvirus RNA recombination and promotes viral replication via facilitating assembly of the viral replicase complex.

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Prasanth, K Reddisiva; Barajas, Daniel; Nagy, Peter D

2015-03-01

RNA viruses co-opt a large number of cellular proteins that affect virus replication and, in some cases, viral genetic recombination. RNA recombination helps viruses in an evolutionary arms race with the host's antiviral responses and adaptation of viruses to new hosts. Tombusviruses and a yeast model host are used to identify cellular factors affecting RNA virus replication and RNA recombination. In this study, we have examined the role of the conserved Rpn11p metalloprotease subunit of the proteasome, which couples deubiquitination and degradation of proteasome substrates, in tombusvirus replication and recombination in Saccharomyces cerevisiae and plants. Depletion or mutations of Rpn11p lead to the rapid formation of viral RNA recombinants in combination with reduced levels of viral RNA replication in yeast or in vitro based on cell extracts. Rpn11p interacts with the viral replication proteins and is recruited to the viral replicase complex (VRC). Analysis of the multifunctional Rpn11p has revealed that the primary role of Rpn11p is to act as a "matchmaker" that brings the viral p92(pol) replication protein and the DDX3-like Ded1p/RH20 DEAD box helicases into VRCs. Overexpression of Ded1p can complement the defect observed in rpn11 mutant yeast by reducing TBSV recombination. This suggests that Rpn11p can suppress tombusvirus recombination via facilitating the recruitment of the cellular Ded1p helicase, which is a strong suppressor of viral recombination, into VRCs. Overall, this work demonstrates that the co-opted Rpn11p, which is involved in the assembly of the functional proteasome, also functions in the proper assembly of the tombusvirus VRCs. RNA viruses evolve rapidly due to genetic changes based on mutations and RNA recombination. Viral genetic recombination helps viruses in an evolutionary arms race with the host's antiviral responses and facilitates adaptation of viruses to new hosts. Cellular factors affect viral RNA recombination, although the role

Modern marketing approach: Concept of viral marketing

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Mihailović Lidija B.

2017-01-01

Full Text Available Today, viral marketing is one of the most effective forms of marketing and it can be used to raise awareness about the product/service of a specific company. This type of marketing thrives in a modern environment, where final users (buyers/clients dominate by spreading messages within themselves. Boosted by the advantages that modern technology brings, viral marketing is booming in the online world. For the first time, small brands have a chance to make their appearance in the global market ad challenge the dominating position of the historically top brands. All they need is content that draws attention and modern, digital culture will help spread their message. Viral marketing is the future. And with the growth of social media and other channels, marketing managers need to be careful, because it is a thin line between a good and a bad (backfired viral campaign.

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.

Effects of intermittent fasting on glucose and lipid metabolism.

Science.gov (United States)

Antoni, Rona; Johnston, Kelly L; Collins, Adam L; Robertson, M Denise

2017-08-01

Two intermittent fasting variants, intermittent energy restriction (IER) and time-restricted feeding (TRF), have received considerable interest as strategies for weight-management and/or improving metabolic health. With these strategies, the pattern of energy restriction and/or timing of food intake are altered so that individuals undergo frequently repeated periods of fasting. This review provides a commentary on the rodent and human literature, specifically focusing on the effects of IER and TRF on glucose and lipid metabolism. For IER, there is a growing evidence demonstrating its benefits on glucose and lipid homeostasis in the short-to-medium term; however, more long-term safety studies are required. Whilst the metabolic benefits of TRF appear quite profound in rodents, findings from the few human studies have been mixed. There is some suggestion that the metabolic changes elicited by these approaches can occur in the absence of energy restriction, and in the context of IER, may be distinct from those observed following similar weight-loss achieved via modest continuous energy restriction. Mechanistically, the frequently repeated prolonged fasting intervals may favour preferential reduction of ectopic fat, beneficially modulate aspects of adipose tissue physiology/morphology, and may also impinge on circadian clock regulation. However, mechanistic evidence is largely limited to findings from rodent studies, thus necessitating focused human studies, which also incorporate more dynamic assessments of glucose and lipid metabolism. Ultimately, much remains to be learned about intermittent fasting (in its various forms); however, the findings to date serve to highlight promising avenues for future research.

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.

[Effect of intermittent fasting on physiology and gut microbiota in presenium rats].

Science.gov (United States)

Rong, Zu-Hua; Liang, Shao-Cong; Lu, Jun-Qi; He, Yan; Luo, Yue-Mei; You, Chao; Xia, Geng-Hong; M, Prabhakar; Li, Pan; Zhou, Hong-Wei

2016-04-20

To investigate the effect of intermittent fasting on metabolize and gut microbiota in obese presenium rats fed with high-fat-sugar-diet. We fed the Wistar rats with high-fat and high-sugar diet to induce adiposity, and the rats for intermittent fasting were selected base on their body weight. The rats were subjected to fasting for 72 h every 2 weeks for 18 weeks. OGTT test was performed and fasting blood samples and fecal samples were collected for measurement of TC, TG, HDL-C and LDL-C and sequence analysis of fecal 16S rRNA V4 tags using Illumina. Gut microbial community structure was analyzed with QIIME and LEfSe. After the intervention, the body weight of the fasting rats was significantly lower than that in high-fat diet group (P<0.01). OGTT results suggested impairment of sugar tolerance in the fasting group, which showed a significantly larger AUC than compared with the high-fat diet group (P<0.05). Intermittent fasting significantly reduced blood HDL-C and LDL-C levels (P<0.05) and partially restored liver steatosis, and improved the gut microbiota by increasing the abundance of YS2, RF32 and Helicobacteraceae and reducing Lactobacillus, Roseburia, Erysipelotrichaceae and Ralstonia. Bradyrhizobiaceae was found to be positively correlated with CHOL and HDL-C, and RF39 was inversely correlated with the weight of the rats. Intermittent fasting can decrease the body weight and blood lipid levels and restore normal gut microbiota but can cause impairment of glucose metabolism in obese presenium rats.

A novel adjustable automated system for inducing chronic intermittent hypoxia in mice.

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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.

Sympatho-adrenal activation by chronic intermittent hypoxia

OpenAIRE

Prabhakar, Nanduri R.; Kumar, Ganesh K.; Peng, Ying-Jie

2012-01-01

Recurrent apnea with chronic intermittent hypoxia (CIH) is a major clinical problem in adult humans and infants born preterm. Patients with recurrent apnea exhibit heightened sympathetic activity as well as elevated plasma catecholamine levels, and these phenotypes are effectively recapitulated in rodent models of CIH. This article summarizes findings from studies addressing sympathetic activation in recurrent apnea patients and rodent models of CIH and the underlying cellular and molecular m...

ViralEpi v1.0: a high-throughput spectrum of viral epigenomic methylation profiles from diverse diseases.

Science.gov (United States)

Khan, Mohd Shoaib; Gupta, Amit Kumar; Kumar, Manoj

2016-01-01

To develop a computational resource for viral epigenomic methylation profiles from diverse diseases. Methylation patterns of Epstein-Barr virus and hepatitis B virus genomic regions are provided as web platform developed using open source Linux-Apache-MySQL-PHP (LAMP) bundle: programming and scripting languages, that is, HTML, JavaScript and PERL. A comprehensive and integrated web resource ViralEpi v1.0 is developed providing well-organized compendium of methylation events and statistical analysis associated with several diseases. Additionally, it also facilitates 'Viral EpiGenome Browser' for user-affable browsing experience using JavaScript-based JBrowse. This web resource would be helpful for research community engaged in studying epigenetic biomarkers for appropriate prognosis and diagnosis of diseases and its various stages.

Intermittency in multiparticle production analyzed by means of stochastic theories

International Nuclear Information System (INIS)

Bartl, A.; Suzuki, N.

1990-01-01

Intermittency in multiparticle production is described by means of probability distributions derived from pure birth stochastic equations. The UA1, TASSO, NA22 and cosmic ray data are analyzed. 24 refs., 1 fig. (Authors)

The influence of job stress, social support and health status on intermittent and chronic sleep disturbance: an 8-year longitudinal analysis.

Science.gov (United States)

Gosling, John A; Batterham, Philip J; Glozier, Nick; Christensen, Helen

2014-08-01

To determine the role of health status and social support in the relationship between job stress and sleep disturbance, for both intermittent and chronic sleep disturbance. A total of 1946 mid-life adults completed three questionnaires spanning an 8-year time frame. Sleep disturbance was assessed at each time point, and participants were classified as experiencing intermittent, chronic or no sleep disturbance across this 8-year period. Independent variables included a range of job stress measures, social support, physical and mental health, and demographic characteristics. After controlling for physical and mental health, perceived lack of job marketability increased risk of intermittent sleep disturbance (odds ratio (OR)=1.33, p=0.012). No other job stress measures were associated with either intermittent or chronic sleep disturbance after adjusting for years of education, social support, and employment status. Poorer mental and physical health status, although significantly increasing odds for intermittent sleep disturbance, represented a significantly greater increase in the odds for chronic sleep disturbance over and above intermittent disturbance (OR=0.96, pjob stress had an independent effect on chronic or intermittent sleep disturbance independent of health, social support, and education. Risk profiles for intermittent and chronic sleep disturbance did not differ with regard to job stress; however, various demographic and social support factors were distinguishing factors. Health status, both physical and mental, also showed a significantly greater impact on chronic sleep disturbance than intermittent sleep disturbance. Karasek's model of job strain had little value in predicting sleep disturbance outcomes. Copyright © 2014 Elsevier B.V. All rights reserved.

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.

Psychosocial distress of part-time occlusion in children with intermittent exotropia.

Science.gov (United States)

Kim, Ungsoo Samuel; Park, Subin; Yoo, Hee Jeong; Hwang, Jeong-Min

2013-01-01

To evaluate the psychosocial distress of part-time occlusion therapy in intermittent exotropia. A total of 25 children (15 males and 10 females, aged 3 to 7 years, mean age 4.7 years) with intermittent exotropia were enrolled. Behavioral and psychosocial problems were assessed by the Korean Child Behavior Checklist (K-CBCL), which consists of eight categories of withdrawal, somatic problems, depression/anxiety, social problems, thought problems, attention problems, delinquent behavior, and aggressive behavior, and the Amblyopia Treatment Index (ATI). The ATI was designed to evaluate the three factors of compliance, adverse effect, and social stigma. The Parenting Stress Index (PSI) is a parent self-report designed to identify potentially dysfunctional parent-child systems. The K-CBCL was obtained before and after occlusion therapy, and the ATI and PSI were taken from parents only after occlusion therapy. We evaluated the change on the K-CBCL and the correlation between the K-CBCL and ATI. The attention problem assessed by the K-CBCL significantly decreased after occlusion therapy. On the ATI, the social stigma was relatively lower than compliance and adverse effect factors (Likert scale 2.64, 3.11, and 3.11, respectively). The somatic problem assessed by the K-CBCL and compliance on the ATI were significantly correlated (p = 0.014). There was no significant change in percentile scores of each subscale (parental dominant scale and child dominant scale) of the PSI. Total stress index before and after occlusion therapy was 97.16 ± 8.38 and 97.00 ± 8.16 respectively (p = 0.382). Occlusion therapy may influence the psychosocial impact on intermittent exotropia patients. Part-time occlusion significantly decreased the attention problem in children with intermittent strabismus. Children with a high somatic problem score on the KCBCL showed poor compliance to the part-time occlusion.

Characterizing the effects of intermittent faults on a processor for dependability enhancement strategy.

Science.gov (United States)

Wang, Chao Saul; Fu, Zhong-Chuan; Chen, Hong-Song; Wang, Dong-Sheng

2014-01-01

As semiconductor technology scales into the nanometer regime, intermittent faults have become an increasing threat. This paper focuses on the effects of intermittent faults on NET versus REG on one hand and the implications for dependability strategy on the other. First, the vulnerability characteristics of representative units in OpenSPARC T2 are revealed, and in particular, the highly sensitive modules are identified. Second, an arch-level dependability enhancement strategy is proposed, showing that events such as core/strand running status and core-memory interface events can be candidates of detectable symptoms. A simple watchdog can be deployed to detect application running status (IEXE event). Then SDC (silent data corruption) rate is evaluated demonstrating its potential. Third and last, the effects of traditional protection schemes in the target CMT to intermittent faults are quantitatively studied on behalf of the contribution of each trap type, demonstrating the necessity of taking this factor into account for the strategy.

Characterizing the Effects of Intermittent Faults on a Processor for Dependability Enhancement Strategy

Directory of Open Access Journals (Sweden)

Chao(Saul Wang

2014-01-01

Full Text Available As semiconductor technology scales into the nanometer regime, intermittent faults have become an increasing threat. This paper focuses on the effects of intermittent faults on NET versus REG on one hand and the implications for dependability strategy on the other. First, the vulnerability characteristics of representative units in OpenSPARC T2 are revealed, and in particular, the highly sensitive modules are identified. Second, an arch-level dependability enhancement strategy is proposed, showing that events such as core/strand running status and core-memory interface events can be candidates of detectable symptoms. A simple watchdog can be deployed to detect application running status (IEXE event. Then SDC (silent data corruption rate is evaluated demonstrating its potential. Third and last, the effects of traditional protection schemes in the target CMT to intermittent faults are quantitatively studied on behalf of the contribution of each trap type, demonstrating the necessity of taking this factor into account for the strategy.

Turbulence and intermittent transport at the boundary of magnetized plasmas

DEFF Research Database (Denmark)

Garcia, O.E.; Naulin, V.; Nielsen, A.H.

2005-01-01

Numerical fluid simulations of interchange turbulence for geometry and parameters relevant to the boundary region of magnetically confined plasmas are shown to result in intermittent transport qualitatively similar to recent experimental measurements. The two-dimensional simulation domain features...... a forcing region with spatially localized sources of particles and heat outside which losses due to the motion along open magnetic-field lines dominate, corresponding to the edge region and the scrape-off layer, respectively. Turbulent states reveal intermittent eruptions of hot plasma from the edge region...... fluctuation wave forms and transport statistics are also in a good agreement with those derived from the experiments. Associated with the turbulence bursts are relaxation oscillations in the particle and heat confinements as well as in the kinetic energy of the sheared poloidal flows. The formation of blob...

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.

A comprehensive and quantitative exploration of thousands of viral genomes

Science.gov (United States)

Mahmoudabadi, Gita

2018-01-01

The complete assembly of viral genomes from metagenomic datasets (short genomic sequences gathered from environmental samples) has proven to be challenging, so there are significant blind spots when we view viral genomes through the lens of metagenomics. One approach to overcoming this problem is to leverage the thousands of complete viral genomes that are publicly available. Here we describe our efforts to assemble a comprehensive resource that provides a quantitative snapshot of viral genomic trends – such as gene density, noncoding percentage, and abundances of functional gene categories – across thousands of viral genomes. We have also developed a coarse-grained method for visualizing viral genome organization for hundreds of genomes at once, and have explored the extent of the overlap between bacterial and bacteriophage gene pools. Existing viral classification systems were developed prior to the sequencing era, so we present our analysis in a way that allows us to assess the utility of the different classification systems for capturing genomic trends. PMID:29624169

Effect of intermittent versus continuous energy restriction on weight loss, maintenance and cardiometabolic risk: A randomized 1-year trial.

Science.gov (United States)

Sundfør, T M; Svendsen, M; Tonstad, S

2018-07-01

Long-term adherence to conventional weight-loss diets is limited while intermittent fasting has risen in popularity. We compared the effects of intermittent versus continuous energy restriction on weight loss, maintenance and cardiometabolic risk factors in adults with abdominal obesity and ≥1 additional component of metabolic syndrome. In total 112 participants (men [50%] and women [50%]) aged 21-70 years with BMI 30-45 kg/m 2 (mean 35.2 [SD 3.7]) were randomized to intermittent or continuous energy restriction. A 6-month weight-loss phase including 10 visits with dieticians was followed by a 6-month maintenance phase without additional face-to-face counselling. The intermittent energy restriction group was advised to consume 400/600 kcal (female/male) on two non-consecutive days. Based on dietary records both groups reduced energy intake by ∼26-28%. Weight loss was similar among participants in the intermittent and continuous energy restriction groups (8.0 kg [SD 6.5] versus 9.0 kg [SD 7.1]; p = 0.6). There were favorable improvements in waist circumference, blood pressure, triglycerides and HDL-cholesterol with no difference between groups. Weight regain was minimal and similar between the intermittent and continuous energy restriction groups (1.1 kg [SD 3.8] versus 0.4 kg [SD 4.0]; p = 0.6). Intermittent restriction participants reported higher hunger scores than continuous restriction participants on a subjective numeric rating scale (4.7 [SD 2.2] vs 3.6 [SD 2.2]; p = 0.002). Both intermittent and continuous energy restriction resulted in similar weight loss, maintenance and improvements in cardiovascular risk factors after one year. However, feelings of hunger may be more pronounced during intermittent energy restriction. www.clinicaltrials.govNCT02480504. Copyright © 2018 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine

Intermittency in multiparticle production produced by low momentum transfer at high energies

International Nuclear Information System (INIS)

Jang, Han Il; Jeong, Eun Mi; Kim, Jae Yool; Kim, Jae Young; Kim, Min Kyoung; Kim, Sin Joung; Kim, Tae Ick; Kim, Yeon Kyoung; Lee, Jin Ho; Lim, In Taek; Pac, Myoung Youl; Kim, Chong Oh; Bahk, Sang Yull

1998-01-01

We show the intermittent behavior of the distribution of the pseudo-rapidities of secondary charged particles produced by nucleus-nucleus interactions. In particular, using the modified G moments, which can be defined to suppress the statistical fluctuations, we study the intermittency in the low multiplicity processes produced by the 14.6-GeV/nucleon 28 Si - nucleus interactions. We have shown experimentally that the basic function B q,k (M), behaving as M λ(q,k) at large M, has the basic fractal behavior and that the exponent λ(q,k) depends linearly on the number of multiplicity in a bin

Intermittent Switching between Soliton Dynamic States in a Perturbed Sine-Gordon Model

DEFF Research Database (Denmark)

Sørensen, Mads Peter; Arley, N.; Christiansen, Peter Leth

1983-01-01

Chaotic intermittency between soliton dynamic states has been found in a perturbed sine-Gordon system in the absence of an external ac driving term. The system is a model of a long Josephson oscillator with constant loss and bias current in an external magnetic field. The results predict the exis......Chaotic intermittency between soliton dynamic states has been found in a perturbed sine-Gordon system in the absence of an external ac driving term. The system is a model of a long Josephson oscillator with constant loss and bias current in an external magnetic field. The results predict...

The intermittency of wind, solar, and renewable electricity generators. Technical barrier or rhetorical excuse?

Energy Technology Data Exchange (ETDEWEB)

Sovacool, Benjamin K. [Centre on Asia and Globalisation, Lee Kuan Yew School of Public Policy, National University of Singapore, 469C Bukit Timah Road, Singapore 259772 (Singapore)

2009-09-15

A consensus has long existed within the electric utility sector of the United States that renewable electricity generators such as wind and solar are unreliable and intermittent to a degree that they will never be able to contribute significantly to electric utility supply or provide baseload power. This paper asks three interconnected questions: (1) What do energy experts really think about renewables in the United States?; (2) To what degree are conventional baseload units reliable?; (3) Is intermittency a justifiable reason to reject renewable electricity resources? To provide at least a few answers, the author conducted 62 formal, semi-structured interviews at 45 different institutions including electric utilities, regulatory agencies, interest groups, energy systems manufacturers, nonprofit organizations, energy consulting firms, universities, national laboratories, and state institutions in the United States. In addition, an extensive literature review of government reports, technical briefs, and journal articles was conducted to understand how other countries have dealt with (or failed to deal with) the intermittent nature of renewable resources around the world. It was concluded that the intermittency of renewables can be predicted, managed, and mitigated, and that the current technical barriers are mainly due to the social, political, and practical inertia of the traditional electricity generation system. (author)

Intermittent fasting interventions for treatment of overweight and obesity in adults: a systematic review and meta-analysis.

Science.gov (United States)

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

2018-02-01

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. 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 limited. This review included overweight or obese (BMI ≥25 kg/m) adults (≥18 years). Intermittent energy restriction was defined as consumption of ≤800 kcal on at least one day, but no more than six days per week. Intermittent energy restriction interventions were compared to no treatment (ad libitum diet) or usual care (continuous energy restriction ∼25% of recommended energy intake). Included interventions had a minimum duration of 12 weeks from baseline to post outcome measurements. The types of studies included were randomized and pseudo-randomized controlled trials. The primary outcome of this review was change in body weight. Secondary outcomes included: i) anthropometric outcomes (change in BMI, waist circumference, fat mass, fat free mass); ii) cardio-metabolic outcomes (change in blood glucose and insulin, lipoprotein profiles and blood pressure); and iii) lifestyle outcomes: diet, physical activity, quality of life and adverse events. A systematic search was conducted from database inception to November 2015. The following electronic databases were searched: MEDLINE, Embase, CINAHL, Cochrane Library, ClinicalTrials.gov, ISRCTN registry, and anzctr.org.au for English language published studies, protocols and trials. Two independent reviewers evaluated the methodological quality of included studies using the standardized critical appraisal instruments from the Joanna Briggs Institute. Data were extracted from papers included in the review by two independent reviewers using the standardized data

Viral haemorrhagic fever and vascular alterations.

Science.gov (United States)

Aleksandrowicz, P; Wolf, K; Falzarano, D; Feldmann, H; Seebach, J; Schnittler, H

2008-02-01

Pathogenesis of viral haemorrhagic fever (VHF) is closely associated with alterations of the vascular system. Among the virus families causing VHF, filoviruses (Marburg and Ebola) are the most fatal, and will be focused on here. After entering the body, Ebola primarily targets monocytes/macrophages and dendritic cells. Infected dendritic cells are largely impaired in their activation potency, likely contributing to the immune suppression that occurs during filovirus infection. Monocytes/macrophages, however, immediately activate after viral contact and release reasonable amounts of cytokines that target the vascular system, particularly the endothelial cells. Some underlying molecular mechanisms such as alteration of the vascular endothelial cadherin/catenin complex, tyrosine phosphorylation, expression of cell adhesion molecules, tissue factor and the effect of soluble viral proteins released from infected cells to the blood stream will be discussed.

Discovery of burst oscillations in the intermittent accretion-powered millisecond pulsar HETE J1900.1-2455

NARCIS (Netherlands)

Watts, A.L.; Altamirano, D.; Linares, M.; Patruno, A.; Casella, P.; Cavecchi, Y.; Degenaar, N.; Rea, N.; Soleri, P.; van der Klis, M.; Wijnands, R.

2009-01-01

We report the discovery of burst oscillations from the intermittent accretion-powered millisecond pulsar (AMP) HETE J1900.1-2455, with a frequency ~1 Hz below the known spin frequency. The burst oscillation properties are far more similar to those of the non-AMPs and Aql X-1 (an intermittent AMP

ANTI-VIRAL ACTIVITY OF GLYCIRRHETINIC AND GLYCIRRHIZIC ACIDS

Directory of Open Access Journals (Sweden)

V. V. Zarubaev

2016-01-01

Full Text Available Influenza is a highly contagious human disease. In the course of use of antiviral drugs drug-resistant strains of the virus are formed, resulting in reduced efficiency of the chemotherapy. The review describes the biological activity of glycirrhetinic (GLA and glycirrhizic (GA acids in terms of their use as a therapeutic agent for viral infections. So, these compounds are against a broad spectrum of viruses, including herpes, corona-, alphaand flaviviruses, human immunodeficiency virus, vaccinia virus, poliovirus type I, vesicular stomatitis virus and influenza A virus. These data indicate that anti-viral effect of these compounds is due to several types of activity — direct antiviral effects, effects on cellular proand anti-viral and immunomodulating pathways, in particular by activation of innate immunity system. GA interferes with early steps of the viral reproductive cycle such as virus binding to its receptor, the absorption of the virus by endocytosis or virus decapsidation in the cytoplasm. This is due to the effect of GA-induced reduction of membrane fluidity. Thus, one mechanism for the antiviral activity of GA is that GA molecule increases the rigidity of cellular and viral membranes after incorporation in there. This results in increasing of energy threshold required for the formation of negative curvature at the fusion zones, as well as difficult lateral migration of the virus-receptor complexes. In addition, glycyrrhizin prevents interaction of viral nucleoprotein with cellular protein HMGB1, which is necessary for the viral life cycle. Glycyrrhizin also inhibits the induction of oxidative stress during influenza infection, exhibiting antioxidant properties, which leads to a reduction of virus-induced production of cytokines/chemokines, without affecting the replication of the virus. A wide spectrum of biological activity and effect on various aspects of the viral pathogenesis substantiate the effect of GA and GLA as a component

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.

Simultaneous Multislice Echo Planar Imaging With Blipped Controlled Aliasing in Parallel Imaging Results in Higher Acceleration: A Promising Technique for Accelerated Diffusion Tensor Imaging of Skeletal Muscle.

Science.gov (United States)

Filli, Lukas; Piccirelli, Marco; Kenkel, David; Guggenberger, Roman; Andreisek, Gustav; Beck, Thomas; Runge, Val M; Boss, Andreas

2015-07-01

The aim of this study was to investigate the feasibility of accelerated diffusion tensor imaging (DTI) of skeletal muscle using echo planar imaging (EPI) applying simultaneous multislice excitation with a blipped controlled aliasing in parallel imaging results in higher acceleration unaliasing technique. After federal ethics board approval, the lower leg muscles of 8 healthy volunteers (mean [SD] age, 29.4 [2.9] years) were examined in a clinical 3-T magnetic resonance scanner using a 15-channel knee coil. The EPI was performed at a b value of 500 s/mm2 without slice acceleration (conventional DTI) as well as with 2-fold and 3-fold acceleration. Fractional anisotropy (FA) and mean diffusivity (MD) were measured in all 3 acquisitions. Fiber tracking performance was compared between the acquisitions regarding the number of tracks, average track length, and anatomical precision using multivariate analysis of variance and Mann-Whitney U tests. Acquisition time was 7:24 minutes for conventional DTI, 3:53 minutes for 2-fold acceleration, and 2:38 minutes for 3-fold acceleration. Overall FA and MD values ranged from 0.220 to 0.378 and 1.595 to 1.829 mm2/s, respectively. Two-fold acceleration yielded similar FA and MD values (P ≥ 0.901) and similar fiber tracking performance compared with conventional DTI. Three-fold acceleration resulted in comparable MD (P = 0.199) but higher FA values (P = 0.006) and significantly impaired fiber tracking in the soleus and tibialis anterior muscles (number of tracks, P DTI of skeletal muscle with similar image quality and quantification accuracy of diffusion parameters. This may increase the clinical applicability of muscle anisotropy measurements.

Distribution patterns of fish assemblages in an Eastern Mediterranean intermittent river

Directory of Open Access Journals (Sweden)

Vardakas L.

2015-01-01

Full Text Available The distribution patterns of fish assemblages within streams can provide insights for river type classifications and may warrant specific conservation actions. However, there is limited knowledge of how fish assemblages assort along a longitudinal axis in Mediterranean intermittent streams. Patterns in spatial and temporal distribution of fish communities were analysed in a Mediterranean intermittent river (Evrotas River located in Southern Greece, hosting three endemic range restricted species of high conservation concern, during the period 2007−2009, with 80% of the river’s total length desiccating in the 2007 and 2008 droughts. The general trend was an increase in fish density and species richness along an upstream-downstream gradient. Fish assemblages from upstream to downstream were characterized by a decrease of the most rheophilic species (Squalius keadicus and an increase of the most stagnophilic species (Tropidophoxinellus spartiaticus. Three river segments, characterized by a high degree of homogeneity were delineated. Habitat and environmental preferences for the studied fish species were identified, with elevation and low flowing habitats being the most important environmental factors affecting fish distribution patterns. The current study provides evidence that even in an intermittent river an assemblage pattern following a longitudinal gradient can be identified, mainly due to the lack of instream barriers that allows recolonization after flow resumption.

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

Rapid and highly fieldable viral diagnostic

Energy Technology Data Exchange (ETDEWEB)

McKnight, Timothy E.

2016-12-20

The present invention relates to a rapid, highly fieldable, nearly reagentless diagnostic to identify active RNA viral replication in a live, infected cells, and more particularly in leukocytes and tissue samples (including biopsies and nasal swabs) using an array of a plurality of vertically-aligned nanostructures that impale the cells and introduce a DNA reporter construct that is expressed and amplified in the presence of active viral replication.

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

Physical non-viral gene delivery methods for tissue engineering.

Science.gov (United States)

Mellott, Adam J; Forrest, M Laird; Detamore, Michael S

2013-03-01

The integration of gene therapy into tissue engineering to control differentiation and direct tissue formation is not a new concept; however, successful delivery of nucleic acids into primary cells, progenitor cells, and stem cells has proven exceptionally challenging. Viral vectors are generally highly effective at delivering nucleic acids to a variety of cell populations, both dividing and non-dividing, yet these viral vectors are marred by significant safety concerns. Non-viral vectors are preferred for gene therapy, despite lower transfection efficiencies, and possess many customizable attributes that are desirable for tissue engineering applications. However, there is no single non-viral gene delivery strategy that "fits-all" cell types and tissues. Thus, there is a compelling opportunity to examine different non-viral vectors, especially physical vectors, and compare their relative degrees of success. This review examines the advantages and disadvantages of physical non-viral methods (i.e., microinjection, ballistic gene delivery, electroporation, sonoporation, laser irradiation, magnetofection, and electric field-induced molecular vibration), with particular attention given to electroporation because of its versatility, with further special emphasis on Nucleofection™. In addition, attributes of cellular character that can be used to improve differentiation strategies are examined for tissue engineering applications. Ultimately, electroporation exhibits a high transfection efficiency in many cell types, which is highly desirable for tissue engineering applications, but electroporation and other physical non-viral gene delivery methods are still limited by poor cell viability. Overcoming the challenge of poor cell viability in highly efficient physical non-viral techniques is the key to using gene delivery to enhance tissue engineering applications.

Physical non-viral gene delivery methods for tissue engineering

Science.gov (United States)

Mellott, Adam J.; Forrest, M. Laird; Detamore, Michael S.

2016-01-01

The integration of gene therapy into tissue engineering to control differentiation and direct tissue formation is not a new concept; however, successful delivery of nucleic acids into primary cells, progenitor cells, and stem cells has proven exceptionally challenging. Viral vectors are generally highly effective at delivering nucleic acids to a variety of cell populations, both dividing and non-dividing, yet these viral vectors are marred by significant safety concerns. Non-viral vectors are preferred for gene therapy, despite lower transfection efficiencies, and possess many customizable attributes that are desirable for tissue engineering applications. However, there is no single non-viral gene delivery strategy that “fits-all” cell types and tissues. Thus, there is a compelling opportunity to examine different non-viral vectors, especially physical vectors, and compare their relative degrees of success. This review examines the advantages and disadvantages of physical non-viral methods (i.e., microinjection, ballistic gene delivery, electroporation, sonoporation, laser irradiation, magnetofection, and electric field-induced molecular vibration), with particular attention given to electroporation because of its versatility, with further special emphasis on Nucleofection™. In addition, attributes of cellular character that can be used to improve differentiation strategies are examined for tissue engineering applications. Ultimately, electroporation exhibits a high transfection efficiency in many cell types, which is highly desirable for tissue engineering applications, but electroporation and other physical non-viral gene delivery methods are still limited by poor cell viability. Overcoming the challenge of poor cell viability in highly efficient physical non-viral techniques is the key to using gene delivery to enhance tissue engineering applications. PMID:23099792

Viral kinetics of Enterovirus 71 in human abdomyosarcoma cells

Science.gov (United States)

Lu, Jing; He, Ya-Qing; Yi, Li-Na; Zan, Hong; Kung, Hsiang-Fu; He, Ming-Liang

2011-01-01

AIM: To characterise the viral kinetics of enterovirus 71 (EV71). METHODS: In this study, human rhabdomyosarcoma (RD) cells were infected with EV71 at different multiplicity of infection (MOI). After infection, the cytopathic effect (CPE) was monitored and recorded using a phase contrast microscope associated with a CCD camera at different time points post viral infection (0, 6, 12, 24 h post infection). Cell growth and viability were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in both EV71 infected and mock infected cells at each time point. EV71 replication kinetics in RD cells was determined by measuring the total intracellular viral RNA with real-time reverse-transcription polymerase chain reaction (qRT-PCR). Also, the intracellular and extracellular virion RNA was isolated and quantified at different time points to analyze the viral package and secretion. The expression of viral protein was determined by analyze the levels of viral structure protein VP1 with Western blotting. RESULTS: EV71 infection induced a significant CPE as early as 6 h post infection (p.i.) in both RD cells infected with high ratio of virus (MOI 10) and low ratio of virus (MOI 1). In EV71 infected cells, the cell growth was inhibited and the number of viable cells was rapidly decreased in the later phase of infection. EV71 virions were uncoated immediately after entry. The intracellular viral RNA began to increase at as early as 3 h p.i. and the exponential increase was found between 3 h to 6 h p.i. in both infected groups. For viral structure protein synthesis, results from western-blot showed that intracellular viral protein VP1 could not be detected until 6 h p.i. in the cells infected at either MOI 1 or MOI 10; and reached the peak at 9 h p.i. in the cells infected with EV71 at both MOI 1 and MOI 10. Simultaneously, the viral package and secretion were also actively processed as the virus underwent rapid replication. The viral package kinetics

Computing moving and intermittent queue propagation in highway work zones.

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2012-07-01

Drivers may experience intermittent congestion and moving queue conditions in work zones due to several reasons such as presence of lane closure, roadway geometric changes, higher demand, lower speed, and reduced capacity. The congestion and queue ha...

Lactic acidosis and diastolic hypotension after intermittent albuterol nebulization in a pediatric patient

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Tehila A. Saadia

2015-01-01

Full Text Available We describe a case of 13-year-old female with intermittent asthma who developed lactic acidosis and diastolic hypotension after receiving intermittent albuterol nebulizer treatment. She presented to the emergency department (ED with sudden onset of shortness of breath and chest pain. She received two albuterol nebulizer treatments at home without symptomatic relief. She was treated in the ED with intermittent albuterol nebulization for a total of 22.5 mg over the next 5 hours. A decrease in diastolic blood pressure from 60 mmHg to 40 mmHg was noted after the treatment. Blood lactate level was 5.9 mmol/L. She recovered from it and was discharged to home but she had recurrence of shortness of breath and presented to the ED two days later. She was treated with albuterol nebulization for a total of 17.5 mg over the next two and half hours and developed diastolic hypotension again, as low as 30 mm Hg. After discontinuation of albuterol nebulization, her BP normalized. Cardiopulmonary and metabolic side effects of continuous albuterol therapy have been reported in the recent medical literature. Our patient, however, developed these adverse effects on intermittent albuterol nebulizer treatment. It is important for the pediatrician to recognize the adverse effects of β2-agonist therapy to avoid carrying out extensive workup for hypotension and hyperlactatemia prolonging hospital stay.

Intermittency and geometrical statistics of three-dimensional homogeneous magnetohydrodynamic turbulence: A wavelet viewpoint

International Nuclear Information System (INIS)

Yoshimatsu, Katsunori; Kawahara, Yasuhiro; Schneider, Kai; Okamoto, Naoya; Farge, Marie

2011-01-01

Scale-dependent and geometrical statistics of three-dimensional incompressible homogeneous magnetohydrodynamic turbulence without mean magnetic field are examined by means of the orthogonal wavelet decomposition. The flow is computed by direct numerical simulation with a Fourier spectral method at resolution 512 3 and a unit magnetic Prandtl number. Scale-dependent second and higher order statistics of the velocity and magnetic fields allow to quantify their intermittency in terms of spatial fluctuations of the energy spectra, the flatness, and the probability distribution functions at different scales. Different scale-dependent relative helicities, e.g., kinetic, cross, and magnetic relative helicities, yield geometrical information on alignment between the different scale-dependent fields. At each scale, the alignment between the velocity and magnetic field is found to be more pronounced than the other alignments considered here, i.e., the scale-dependent alignment between the velocity and vorticity, the scale-dependent alignment between the magnetic field and its vector potential, and the scale-dependent alignment between the magnetic field and the current density. Finally, statistical scale-dependent analyses of both Eulerian and Lagrangian accelerations and the corresponding time-derivatives of the magnetic field are performed. It is found that the Lagrangian acceleration does not exhibit substantially stronger intermittency compared to the Eulerian acceleration, in contrast to hydrodynamic turbulence where the Lagrangian acceleration shows much stronger intermittency than the Eulerian acceleration. The Eulerian time-derivative of the magnetic field is more intermittent than the Lagrangian time-derivative of the magnetic field.

Viral Evasion of Natural Killer Cell Activation

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Yi Ma

2016-04-01

Full Text Available Natural killer (NK cells play a key role in antiviral innate defenses because of their abilities to kill infected cells and secrete regulatory cytokines. Additionally, NK cells exhibit adaptive memory-like antigen-specific responses, which represent a novel antiviral NK cell defense mechanism. Viruses have evolved various strategies to evade the recognition and destruction by NK cells through the downregulation of the NK cell activating receptors. Here, we review the recent findings on viral evasion of NK cells via the impairment of NK cell-activating receptors and ligands, which provide new insights on the relationship between NK cells and viral actions during persistent viral infections.

Viral Evasion of Natural Killer Cell Activation.

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Ma, Yi; Li, Xiaojuan; Kuang, Ersheng

2016-04-12

Natural killer (NK) cells play a key role in antiviral innate defenses because of their abilities to kill infected cells and secrete regulatory cytokines. Additionally, NK cells exhibit adaptive memory-like antigen-specific responses, which represent a novel antiviral NK cell defense mechanism. Viruses have evolved various strategies to evade the recognition and destruction by NK cells through the downregulation of the NK cell activating receptors. Here, we review the recent findings on viral evasion of NK cells via the impairment of NK cell-activating receptors and ligands, which provide new insights on the relationship between NK cells and viral actions during persistent viral infections.

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

HIV Viral Load

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... PF4 Antibody Hepatitis A Testing Hepatitis B Testing Hepatitis C Testing HER2/neu Herpes Testing High-sensitivity C-reactive Protein (hs-CRP) Histamine Histone Antibody HIV Antibody and HIV Antigen (p24) HIV Antiretroviral Drug Resistance Testing, Genotypic HIV Viral Load HLA Testing HLA- ...

Adequacy in dialysis: intermittent versus continuous therapies.

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Misra, M; Nolph, K D

2000-01-01

A vital conceptual difference between intermittent and continuous dialysis therapies is the difference in the relationship between Kt/V urea and dietary protein intake. For a given level of protein intake the intermittent therapies require a higher Kt/V urea due to the reasons mentioned above. The recently released adequacy guidelines by DOQI for intermittent and continuous therapies are based on these assumptions. The link between adequacy targets and patient survival is well documented for an intermittent therapy like HD. For a continuous therapy like CAPD however, the evidence linking improved peritoneal clearance to better survival is not as direct. However, present consensus allows one to extrapolate results based on HD. The concept of earlier and healthier initiation of dialysis is gaining hold and incremental dialysis forms an integral aspect of the whole concept. Tools like urea kinetic modeling give us valuable insight in making mathematical projections about the timing as well as dosing of dialysis. Daily home hemodialysis is still an underutilized modality despite offering best survival figures. Hopefully, with increasing availability of better and simpler machines its use will increase. Still several questions remain unanswered. Despite availability of data in hemodialysis patients suggesting that an increased dialysis prescription leads to a better survival, optimal dialysis dose is yet to be defined. Concerns regarding methodology of such studies and conclusions thereof has been raised. Other issues relating to design of the studies, variation in dialysis delivery, use of uncontrolled historical standards and lack of patient randomization etc also need to be considered when designing such trials. Hopefully an ongoing prospective randomized trial, namely the HEMO study, looking at two precisely defined and carefully maintained dialysis prescriptions will provide some insight into adequacy of dialysis dose and survival. In diabetic patients, the

Viral and cellular subnuclear structures in human cytomegalovirus-infected cells.

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Strang, Blair L

2015-02-01

In human cytomegalovirus (HCMV)-infected cells, a dramatic remodelling of the nuclear architecture is linked to the creation, utilization and manipulation of subnuclear structures. This review outlines the involvement of several viral and cellular subnuclear structures in areas of HCMV replication and virus-host interaction that include viral transcription, viral DNA synthesis and the production of DNA-filled viral capsids. The structures discussed include those that promote or impede HCMV replication (such as viral replication compartments and promyelocytic leukaemia nuclear bodies, respectively) and those whose role in the infected cell is unclear (for example, nucleoli and nuclear speckles). Viral and cellular proteins associated with subnuclear structures are also discussed. The data reviewed here highlight advances in our understanding of HCMV biology and emphasize the complexity of HCMV replication and virus-host interactions in the nucleus. © 2015 The Authors.

Increased MCP-1 gene expression in monocytes of severe OSA patients and under intermittent hypoxia.

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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.

Kolmogorov similarity hypotheses for scalar fields: sampling intermittent turbulent mixing in the ocean and galaxy

International Nuclear Information System (INIS)

Gibson, C.H.

1991-01-01

Kolmogorov's three universal similarity hypotheses are extrapolated to describe scalar fields like temperature mixed by turbulence. The analogous first and second hypotheses for scalars include the effects of Prandtl number and rate-of-strain mixing. Application of velocity and scalar similarity hypotheses to the ocean must take into account the damping of active turbulence by density stratification and the Earth's rotation to form fossil turbulence. By the analogous Kolmogorov third hypothesis for scalars, temperature dissipation rates χ averaged over lengths r > L K should be lognormally distributed with intermittency factors σ 2 that increase with increasing turbulence energy length scales L O as σ ln r 2 approx = μ θ ln(L O /r). Tests of kolmogorovian velocity and scalar universal similarity hypotheses for very large ranges of turbulence length and timescales are provided by data from the ocean and the galactic interstellar medium. These ranges are from 1 to 9 decades in the ocean, and over 12 decades in the interstellar medium. The universal constant for turbulent mixing intermittency μ θ is estimated from oceanic data to be 0.44±0.01, which is remarkably close to estimates for Kolmorgorov's turbulence intermittency constant μ of 0.45±0.05 from galactic as well as atmospheric data. Extreme intermittency complicates the oceanic sampling problem, and may lead to quantitative and qualitative undersampling errors in estimates of mean oceanic dissipation rates and fluxes. Intermittency of turbulence and mixing in the interstellar medium may be a factor in the formation of stars. (author)

Distribution of Chironomidae in a semiarid intermittent river of Brazil.

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