Apostolopoulos, Nikos C; Lahart, Ian M; Plyley, Michael J; Taunton, Jack; Nevill, Alan M; Koutedakis, Yiannis; Wyon, Matthew; Metsios, George S
2018-03-12
Effects of passive static stretching intensity on recovery from unaccustomed eccentric exercise of right knee extensors was investigated in 30 recreationally active males randomly allocated into three groups: high-intensity (70-80% maximum perceived stretch), low-intensity (30-40% maximum perceived stretch), and control. Both stretching groups performed 3 sets of passive static stretching exercises of 60s each for hamstrings, hip flexors, and quadriceps, over 3 consecutive days, post-unaccustomed eccentric exercise. Muscle function (eccentric and isometric peak torque) and blood biomarkers (CK and CRP) were measured before (baseline) and after (24, 48, and 72h) unaccustomed eccentric exercise. Perceived muscle soreness scores were collected immediately (time 0), and after 24, 48, and 72h post-exercise. Statistical time x condition interactions observed only for eccentric peak torque (p=.008). Magnitude-based inference analyses revealed low-intensity stretching had most likely, very likely, or likely beneficial effects on perceived muscle soreness (48-72h and 0-72h) and eccentric peak torque (baseline-24h and baseline-72h), compared with high-intensity stretching. Compared with control, low-intensity stretching had very likely or likely beneficial effects on perceived muscle soreness (0-24h and 0-72h), eccentric peak torque (baseline-48h and baseline-72h), and isometric peak torque (baseline-72h). High-intensity stretching had likely beneficial effects on eccentric peak torque (baseline-48h), but likely harmful effects eccentric peak torque (baseline-24h) and CK (baseline-48h and baseline-72h), compared with control. Therefore, low-intensity stretching is likely to result in small-to-moderate beneficial effects on perceived muscle soreness and recovery of muscle function post-unaccustomed eccentric exercise, but not markers of muscle damage and inflammation, compared with high-intensity or no stretching.
Focused ultrasound transducer spatial peak intensity estimation: a comparison of methods
NASA Astrophysics Data System (ADS)
Civale, John; Rivens, Ian; Shaw, Adam; ter Haar, Gail
2018-03-01
Characterisation of the spatial peak intensity at the focus of high intensity focused ultrasound transducers is difficult because of the risk of damage to hydrophone sensors at the high focal pressures generated. Hill et al (1994 Ultrasound Med. Biol. 20 259-69) provided a simple equation for estimating spatial-peak intensity for solid spherical bowl transducers using measured acoustic power and focal beamwidth. This paper demonstrates theoretically and experimentally that this expression is only strictly valid for spherical bowl transducers without a central (imaging) aperture. A hole in the centre of the transducer results in over-estimation of the peak intensity. Improved strategies for determining focal peak intensity from a measurement of total acoustic power are proposed. Four methods are compared: (i) a solid spherical bowl approximation (after Hill et al 1994 Ultrasound Med. Biol. 20 259-69), (ii) a numerical method derived from theory, (iii) a method using measured sidelobe to focal peak pressure ratio, and (iv) a method for measuring the focal power fraction (FPF) experimentally. Spatial-peak intensities were estimated for 8 transducers at three drive powers levels: low (approximately 1 W), moderate (~10 W) and high (20-70 W). The calculated intensities were compared with those derived from focal peak pressure measurements made using a calibrated hydrophone. The FPF measurement method was found to provide focal peak intensity estimates that agreed most closely (within 15%) with the hydrophone measurements, followed by the pressure ratio method (within 20%). The numerical method was found to consistently over-estimate focal peak intensity (+40% on average), however, for transducers with a central hole it was more accurate than using the solid bowl assumption (+70% over-estimation). In conclusion, the ability to make use of an automated beam plotting system, and a hydrophone with good spatial resolution, greatly facilitates characterisation of the FPF, and consequently gives improved confidence in estimating spatial peak intensity from measurement of acoustic power.
Laryngeal Aerodynamics in Healthy Older Adults and Adults With Parkinson's Disease.
Matheron, Deborah; Stathopoulos, Elaine T; Huber, Jessica E; Sussman, Joan E
2017-03-01
The present study compared laryngeal aerodynamic function of healthy older adults (HOA) to adults with Parkinson's disease (PD) while speaking at a comfortable and increased vocal intensity. Laryngeal aerodynamic measures (subglottal pressure, peak-to-peak flow, minimum flow, and open quotient [OQ]) were compared between HOAs and individuals with PD who had a diagnosis of hypophonia. Increased vocal intensity was elicited via monaurally presented multitalker background noise. At a comfortable speaking intensity, HOAs and individuals with PD produced comparable vocal intensity, rates of vocal fold closure, and minimum flow. HOAs used smaller OQs, higher subglottal pressure, and lower peak-to-peak flow than individuals with PD. Both groups increased speaking intensity when speaking in noise to the same degree. However, HOAs produced increased intensity with greater driving pressure, faster vocal fold closure rates, and smaller OQs than individuals with PD. Monaural background noise elicited equivalent vocal intensity increases in HOAs and individuals with PD. Although both groups used laryngeal mechanisms as expected to increase sound pressure level, they used these mechanisms to different degrees. The HOAs appeared to have better control of the laryngeal mechanism to make changes to their vocal intensity.
Integration of neutron time-of-flight single-crystal Bragg peaks in reciprocal space
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schultz, Arthur J; Joergensen, Mads; Wang, Xiaoping
2014-01-01
The intensity of single crystal Bragg peaks obtained by mapping neutron time-of-flight event data into reciprocal space and integrating in various ways are compared. These include spherical integration with a fixed radius, ellipsoid fitting and integrating of the peak intensity and one-dimensional peak profile fitting. In comparison to intensities obtained by integrating in real detector histogram space, the data integrated in reciprocal space results in better agreement factors and more accurate atomic parameters. Furthermore, structure refinement using integrated intensities from one-dimensional profile fitting is demonstrated to be more accurate than simple peak-minus-background integration.
Within-session responses to high-intensity interval training in spinal cord injury.
Astorino, Todd Anthony; Thum, Jacob S
2018-02-01
Completion of high-intensity interval training (HIIT) increases maximal oxygen uptake and health status, yet its feasibility in persons with spinal cord injury is unknown. To compare changes in cardiorespiratory and metabolic variables between two interval training regimes and moderate intensity exercise. Nine adults with spinal cord injury (duration = 6.8 ± 6.2 year) initially underwent determination of peak oxygen uptake. During subsequent sessions, they completed moderate intensity exercise, HIIT, or sprint interval training. Oxygen uptake, heart rate, and blood lactate concentration were measured. Oxygen uptake and heart rate increased (p < 0.05) during both interval training sessions and were similar (p > 0.05) to moderate intensity exercise. Peak oxygen uptake and heart rate were higher (p < 0.05) with HIIT (90% peak oxygen uptake and 99% peak heart rate) and sprint interval training (80% peak oxygen uptake and 96% peak heart rate) versus moderate intensity exercise. Despite a higher intensity and peak cardiorespiratory strain, all participants preferred interval training versus moderate exercise. Examining long-term efficacy and feasibility of interval training in this population is merited, considering that exercise intensity is recognized as the most important variable factor of exercise programming to optimize maximal oxygen uptake. Implications for Rehabilitation Spinal cord injury (SCI) reduces locomotion which impairs voluntary physical activity, typically resulting in a reduction in peak oxygen uptake and enhanced chronic disease risk. In various able-bodied populations, completion of high-intensity interval training (HIIT) has been consistently reported to improve cardiorespiratory fitness and other health-related outcomes, although its efficacy in persons with SCI is poorly understood. Data from this study in 9 men and women with SCI show similar changes in oxygen uptake and heart in response to HIIT compared to a prolonged bout of aerobic exercise, although peak values were higher in response to HIIT. Due to the higher peak metabolic strain induced by HIIT as well as universal preference for this modality versus aerobic exercise as reported in this study, further work testing utility of HIIT in this population is merited.
Story, Christina; Bryant, Ashley Leak; Phillips, Brett; Bailey, Charlotte; Shields, Edgar W.; Battaglini, Claudio
2018-01-01
Introduction Cardiopulmonary exercise testing (CPET), the gold standard of cardiopulmonary evaluation, is used to determine VO2 levels at different aerobic exercise training intensities; however, it may not be feasible to conduct CPET in all clinical settings. Aims To compare the heart rate reserve (HRR) and percent of 220-age methods for prescribing cycle ergometry exercise intensity using heart rate (HR) against the HRs obtained during a CPET in adults undergoing treatment for acute leukemia (AL). Methods In this exploratory study, part of a larger randomized controlled trial, 14 adults with AL completed CPET on a cycle ergometer with indirect calorimetry within 96 hr of admission to a cancer hospital to determine VO2peak and HR corresponding to low (40% VO2peak), moderate (60% VO2peak), and high (75% VO2peak) exercise intensities. Analyses of variance were used to compare estimated HR for each intensity level using the HRR and percent of 220-age methods with HR determined via VO2peak. Results HR corresponding to low-intensity exercise differed significantly across all three methods (p ≤ .05). No significant differences were observed between HR estimated via the percent of 220-age method and determined via VO2peak at moderate (100 ± 8 and 113 ± 24 bpm, p = .122) or high intensities (125 ± 10 and 123 ± 25 bpm, p = .994). Conclusion In adults with AL, HR-based methods for defining aerobic exercise intensities should be used with caution. At low intensity, neither should be used, while at moderate and high intensities, the percent of 220-age equation might serve as an adequate substitute for CPET. PMID:26933148
Starmer, David J; Guist, Brett P; Tuff, Taylor R; Warren, Sarah C; Williams, Matthew G R
2016-05-01
The purpose of this study was to analyze differences in peak force modulation and time-to-peak thrust in posterior-to-anterior (PA) high-velocity-low-amplitude (HVLA) manipulations in first-year chiropractic students prior to and following a 12-week detraining period. Chiropractic students (n=125) performed 2 thrusts prior to and following a 12-week detraining period: total peak force targets were 400 and 600 N, on a force-sensing table using a PA hand contact of the participant's choice (bilateral hypothenar, bilateral thenar, or cross bilateral). Force modulation was compared to defined target total peak force values of 600 and 400 N, and time-to-peak thrust was compared between data sets using 2-tailed paired t-tests. Total peak force for the 600 N intensity varied by 124.11 + 65.77 N during the pre-test and 123.29 + 61.43 N during the post-test compared to the defined target of 600 N (P = .90); total peak force for the 400 N intensity varied by 44.91 + 34.67 N during the pre-test and 44.60 + 32.63 N during the post-test compared to the defined target of 400 N (P = .57). Time-to-peak thrust for the 400 N total peak force was 137.094 + 42.47 milliseconds during the pre-test and 125.385 + 37.46 milliseconds during the post-test (P = .0004); time-to-peak thrust for the 600 N total peak force was 136.835 + 40.48 milliseconds during the pre-test and 125.385 + 33.78 milliseconds during the post-test (P = .03). The results indicate no drop-off in the ability to modulate force for either thrust intensity, but did indicate a statistically significant change in time-to-peak thrust for the 400 N total peak force thrust intensity in first-year chiropractic students following a 12-week detraining period. Copyright © 2016 National University of Health Sciences. Published by Elsevier Inc. All rights reserved.
Devin, James L; Jenkins, David G; Sax, Andrew T; Hughes, Gareth I; Aitken, Joanne F; Chambers, Suzanne K; Dunn, Jeffrey C; Bolam, Kate A; Skinner, Tina L
2018-06-01
Deteriorations in cardiorespiratory fitness (V˙o 2peak ) and body composition are associated with poor prognosis after colorectal cancer treatment. However, the optimal intensity and frequency of aerobic exercise training to improve these outcomes in colorectal cancer survivors is unknown. This trial compared 8 weeks of moderate-intensity continuous exercise (MICE; 50 minutes; 70% peak heart rate [HR peak ]; 24 sessions), with high-intensity interval exercise (HIIE; 4 × 4 minutes; 85%-95% HR peak ) at an equivalent (HIIE; 24 sessions) and tapered frequency (HIIE-T; 16 sessions) on V˙o 2peak and on lean and fat mass, measured at baseline, 4, 8, and 12 weeks. Increases in V˙o 2peak were significantly greater after both 4 (+3.0 mL·kg -1 ·min -1 , P = .008) and 8 (+2.3 mL·kg -1 ·min -1 , P = .049) weeks of HIIE compared to MICE. After 8 weeks, there was a significantly greater reduction in fat mass after HIIE compared to MICE (-0.7 kg, P = .038). Four weeks after training, the HIIE group maintained elevated V˙o 2peak (+3.3 mL·kg -1 ·min -1 , P = .006) and reduced fat mass (-0.7 kg, P = .045) compared to the MICE group, with V˙o 2peak in the HIIE-T also being superior to the MICE group (+2.8 mL·kg -1 ·min -1 , P = .013). Compared to MICE, HIIE promotes superior improvements and short-term maintenance of V˙o 2peak and fat mass improvements. HIIE training at a reduced frequency also promotes maintainable cardiorespiratory fitness improvements. In addition to promoting accelerated and superior benefits to the current aerobic exercise guidelines, HIIE promotes clinically relevant improvements even with a substantial reduction in exercise training and for a period after withdrawal. Copyright © 2018 Elsevier Inc. All rights reserved.
Gap prepulse inhibition of the auditory late response in healthy subjects.
Ku, Yunseo; Ahn, Joong Woo; Kwon, Chiheon; Suh, Myung-Whan; Lee, Jun Ho; Oh, Seung Ha; Kim, Hee Chan
2015-11-01
The gap-startle paradigm has been used as a behavioral method for tinnitus screening in animal studies. This study aimed to investigate gap prepulse inhibition (GPI) of the auditory late response (ALR) as the objective response of the gap-intense sound paradigm in humans. ALRs were recorded in response to gap-intense and no-gap-intense sound stimuli in 27 healthy subjects. The amplitudes of the baseline-to-peak (N1, P2, and N2) and the peak-to-peak (N1P2 and P2N2) were compared between two averaged ALRs. The variations in the inhibition ratios of N1P2 and P2N2 during the experiment were analyzed by increasing stimuli repetitions. The effect of stimulus parameter adjustments on GPI ratios was evaluated. No-gap-intense sound stimuli elicited greater peak amplitudes than gap-intense sound stimuli, and significant differences were found across all peaks. The overall mean inhibition ratios were significantly lower than 1.0, where the value 1.0 indicates that there were no differences between gap-intense and no-gap-intense sound responses. The initial decline in GPI ratios was shown in N1P2 and P2N2 complexes, and this reduction was nearly complete after 100 stimulus repetitions. Significant effects of gap length and interstimulus interval on GPI ratios were observed. We found significant inhibition of ALR peak amplitudes in performing the gap-intense sound paradigm in healthy subjects. The N1P2 complex represented GPI well in terms of suppression degree and test-retest reliability. Our findings offer practical information for the comparative study of healthy subjects and tinnitus patients using the gap-intense sound paradigm with the ALR. © 2015 Society for Psychophysiological Research.
Comparable Neutrophil Responses for Arm and Intensity-matched Leg Exercise.
Leicht, Christof A; Goosey-Tolfrey, Victoria L; Bishop, Nicolette C
2017-08-01
Arm exercise is performed at lower absolute intensities than lower body exercise. This may impact on intensity-dependent neutrophil responses, and it is unknown whether individuals restricted to arm exercise experience the same changes in the neutrophil response as found for lower body exercise. Therefore, we aimed to investigate the importance of exercise modality and relative exercise intensity on the neutrophil response. Twelve moderately trained men performed three 45-min constant load exercise trials after determination of peak oxygen uptake for arm exercise (V˙O2peak arms) and cycling (V˙O2peak legs): 1) arm cranking exercise at 60% V˙O2peak arms, 2) moderate cycling at 60% V˙O2peak legs, and 3) easy cycling at 60% V˙O2peak arms. Neutrophil numbers in the circulation increased for all exercise trials, but were significantly lower for easy cycling when compared with arm exercise (P = 0.009), mirroring the blunted increase in HR and epinephrine during easy cycling. For all trials, exercising HR explained some of the variation of the neutrophil number 2 h postexercise (R = 0.51-0.69), epinephrine explaining less of this variation (R = 0.21-0.34). The number of neutrophils expressing CXCR2 decreased in the recovery from exercise in all trials (P < 0.05). Arm and leg exercise elicits the same neutrophil response when performed at the same relative intensity, implying that populations restricted to arm exercise might achieve a similar exercise induced neutrophil response as those performing lower body exercise. A likely explanation for this is the higher sympathetic activation and cardiac output for arm and relative intensity-matched leg exercise when compared with easy cycling, which is partly reflected in HR. This study further shows that the downregulation of CXCR2 may be implicated in exercise-induced neutrophilia.
The Application of Quality Identification in Honey by Photoacoustic Spectroscopy.
Tao, Wen-ting; Yuan, Ping; Guo, Wen-juan; Liu, Jian-en
2015-05-01
The photoacoustic spectrum of glucose, sucrose and honey solutions in the visible range are measured by using the single-light photoacoustic spectrometer, and are compared with the spectra from spedtrophotometry method. The spectral characteristics of the above solutions show that the spectral background intensity and spectral profile have some differences for different kinds of solutions. The spectra of the three kinds of solutions all have strong peak value at 485 and 655 nm, but the intensity ratios between the two peaks are different. Besides, there are characteristic peak at 475, 576 and 630 nm for glucose, and the sucrose has apparent characteristic peak at 632 nm, these characteristic peaks can be used for detecting whether the natural honey has been added glucose or sucrose. By comparing two kinds of spectrum of the same solution, the intensity of photoacoustic spectrum is more responsive to the wavelength, indicating photoacoustic spectrometry has a higher sensitivity in the test of material composition.
Jupiter's north and south polar aurorae with IUE data
NASA Technical Reports Server (NTRS)
Livengood, T. A.; Moos, H. W.
1990-01-01
Observations of Jupiter's auroral H2 emissions with the IUE spacecraft, from 1978 through 1990, show that aurorae at the two poles are similar in several respects: (1) emission intensity is modulated with magnetic longitude, north peak emission at lambda (III) (1965) 200 deg, south peak at (1965) about 20 deg; (2) emission intensity and degree of modulation are comparable for both poles; and (3) attenuation by hydrocarbons varies in phase with the intensity, peak attenuation coinciding approximately with peak emission. Increases in the hydrocarbon column are an indicator of either enhanced penetration depth and, thus, energy of the auroral primaries, or of increases in the high-altitude hydrocarbon content caused by modification of the local atmosphere.
Jung, Mary E; Bourne, Jessica E; Little, Jonathan P
2014-01-01
Affect experienced during an exercise session is purported to predict future exercise behaviour. Compared to continuous moderate-intensity exercise (CMI), the affective response to continuous vigorous-intensity exercise (CVI) has consistently been shown to be more aversive. The affective response, and overall tolerability to high-intensity interval training (HIT), is less studied. To date, there has yet to be a comparison between HIT, CVI, and CMI. The purpose of this study was to compare the tolerability and affective responses during HIT to CVI and CMI. This study utilized a repeated measures, randomized, counter-balanced design. Forty-four participants visited the laboratory on four occasions. Baseline fitness testing was conducted to establish peak power output in Watts (W peak). Three subsequent visits involved a single bout of a) HIT, corresponding to 1-minute at ∼ 100% W peak and 1-minute at ∼ 20% W peak for 20 minutes, b) CMI, corresponding to ∼ 40% W peak for 40 minutes, and c) CVI, corresponding to ∼ 80% W peak for 20 minutes. The order of the sessions was randomized. Affective responses were measured before, during and after each session. Task self-efficacy, intentions, enjoyment and preference were measured after sessions. Participants reported greater enjoyment of HIT as compared to CMI and CVI, with over 50% of participants reporting a preference to engage in HIT as opposed to either CMI or CVI. HIT was considered more pleasurable than CVI after exercise, but less pleasurable than CMI at these times. Despite this participants reported being just as confident to engage in HIT as they were CMI, but less confident to engage in CVI. This study highlights the utility of HIT in inactive individuals, and suggests that it may be a viable alternative to traditionally prescribed continuous modalities of exercise for promoting self-efficacy and enjoyment of exercise.
Raman spectroscopy applied to identify metabolites in urine of physically active subjects.
Moreira, Letícia Parada; Silveira, Landulfo; da Silva, Alexandre Galvão; Fernandes, Adriana Barrinha; Pacheco, Marcos Tadeu Tavares; Rocco, Débora Dias Ferraretto Moura
2017-11-01
Raman spectroscopy is a rapid and non-destructive technique suitable for biological fluids analysis. In this work, dispersive Raman spectroscopy has been employed as a rapid and nondestructive technique to detect the metabolites in urine of physically active subjects before and after vigorous 30min pedaling or running compared to sedentary subjects. For so, urine samples from 9 subjects were obtained before and immediately after physical activities and submitted to Raman spectroscopy (830nm excitation, 250mW laser power, 20s integration time) and compared to urine from 5 sedentary subjects. The Raman spectra of urine from sedentary showed peaks related to urea, creatinine, ketone bodies, phosphate and other nitrogenous compounds. These metabolic biomarkers presented peaks with different intensities in the urine of physically active individuals after exercises compared to before, measured by the intensity of selected peaks the Raman spectra, which means different concentrations after training. These peaks presented different intensity values for each subject before physical activity, also behaving differently compared to the post-training: some subjects presented increase while others decrease the intensity. Raman spectroscopy may allow the development of a rapid and non-destructive test for metabolic evaluation of the physical training in active and trained subjects using urine samples, allowing nutrition adjustment with the sport's performance. Copyright © 2017 Elsevier B.V. All rights reserved.
Critical analysis of commonly used fluorescence metrics to characterize dissolved organic matter.
Korak, Julie A; Dotson, Aaron D; Summers, R Scott; Rosario-Ortiz, Fernando L
2014-02-01
The use of fluorescence spectroscopy for the analysis and characterization of dissolved organic matter (DOM) has gained widespread interest over the past decade, in part because of its ease of use and ability to provide bulk DOM chemical characteristics. However, the lack of standard approaches for analysis and data evaluation has complicated its use. This study utilized comparative statistics to systematically evaluate commonly used fluorescence metrics for DOM characterization to provide insight into the implications for data analysis and interpretation such as peak picking methods, carbon-normalized metrics and the fluorescence index (FI). The uncertainty associated with peak picking methods was evaluated, including the reporting of peak intensity and peak position. The linear relationship between fluorescence intensity and dissolved organic carbon (DOC) concentration was found to deviate from linearity at environmentally relevant concentrations and simultaneously across all peak regions. Comparative analysis suggests that the loss of linearity is composition specific and likely due to non-ideal intermolecular interactions of the DOM rather than the inner filter effects. For some DOM sources, Peak A deviated from linearity at optical densities a factor of 2 higher than that of Peak C. For carbon-normalized fluorescence intensities, the error associated with DOC measurements significantly decreases the ability to distinguish compositional differences. An in-depth analysis of FI determined that the metric is mostly driven by peak emission wavelength and less by emission spectra slope. This study also demonstrates that fluorescence intensity follows property balance principles, but the fluorescence index does not. Copyright © 2013 Elsevier Ltd. All rights reserved.
Ozaki, Hayao; Kitada, Tomoharu; Nakagata, Takashi; Naito, Hisashi
2017-05-01
Here, we aimed to compare the effect of a combination of body mass-based resistance exercise and moderate-intensity (55% peak oxygen uptake [ V˙O 2 peak]) walking or high-intensity (75% V˙O 2 peak) walking on muscle size and V˙O 2 peak in untrained older women. A total of 12 untrained older women (mean age 60 ± 2 years) were randomly assigned to either a moderate-intensity aerobic training group (n = 6) or high-intensity aerobic training group (n = 6). Both groups carried out body-mass based (lower body) resistance exercises (2 sets of 10 repetitions) on 3 days/week for 8 weeks. Between these exercises, the participants in the moderate-intensity aerobic training group walked at a previously determined speed equivalent to 55% V˙O 2 peak, whereas those in the high-intensity aerobic training group walked at a speed equivalent to 75% V˙O 2 peak. Muscle thickness of the anterior aspect of the thigh and maximal isokinetic knee extension strength significantly increased in both groups (P < 0.01); these relative changes were negatively correlated with the absolute muscle thickness of the anterior aspect of the thigh value and the relative value of maximal knee strength to body mass at pre-intervention, respectively. A significant group × time interaction was noted for V˙O 2 peak (P < 0.05), which increased only in the high-intensity aerobic training group. Body mass-based resistance training significantly induced muscle hypertrophy in untrained older women. In particular, lower muscle thickness before intervention was associated with greater training-induced growth. Furthermore, V˙O 2 peak can be increased by combined circuit training involving low-load resistance exercise and walking, particularly when a relatively high intensity of walking is maintained. Geriatr Gerontol Int 2017; 17: 779-784. © 2016 Japan Geriatrics Society.
Accurate LC peak boundary detection for ¹⁶O/¹⁸O labeled LC-MS data.
Cui, Jian; Petritis, Konstantinos; Tegeler, Tony; Petritis, Brianne; Ma, Xuepo; Jin, Yufang; Gao, Shou-Jiang S J; Zhang, Jianqiu Michelle
2013-01-01
In liquid chromatography-mass spectrometry (LC-MS), parts of LC peaks are often corrupted by their co-eluting peptides, which results in increased quantification variance. In this paper, we propose to apply accurate LC peak boundary detection to remove the corrupted part of LC peaks. Accurate LC peak boundary detection is achieved by checking the consistency of intensity patterns within peptide elution time ranges. In addition, we remove peptides with erroneous mass assignment through model fitness check, which compares observed intensity patterns to theoretically constructed ones. The proposed algorithm can significantly improve the accuracy and precision of peptide ratio measurements.
Accurate LC Peak Boundary Detection for 16 O/ 18 O Labeled LC-MS Data
Cui, Jian; Petritis, Konstantinos; Tegeler, Tony; Petritis, Brianne; Ma, Xuepo; Jin, Yufang; Gao, Shou-Jiang (SJ); Zhang, Jianqiu (Michelle)
2013-01-01
In liquid chromatography-mass spectrometry (LC-MS), parts of LC peaks are often corrupted by their co-eluting peptides, which results in increased quantification variance. In this paper, we propose to apply accurate LC peak boundary detection to remove the corrupted part of LC peaks. Accurate LC peak boundary detection is achieved by checking the consistency of intensity patterns within peptide elution time ranges. In addition, we remove peptides with erroneous mass assignment through model fitness check, which compares observed intensity patterns to theoretically constructed ones. The proposed algorithm can significantly improve the accuracy and precision of peptide ratio measurements. PMID:24115998
NASA Astrophysics Data System (ADS)
Vieira, Elzo Everton de Sousa; Bispo, Jeyse Aliana Martis; Fernandes, Adriana Barrinha; Silveira, Landulfo
2016-03-01
Diabetes mellitus (DM) and arterial hypertension (AH) are common diseases that, if untreated, predispose the patient to renal failure. This study aimed to evaluate possible biomarkers in the urine of patients with DM and AH capable to predict the chronic renal disease, by means of Raman spectroscopy. Urines were obtained from patients with DM and AH, and separated into four groups: no symptoms of diseases related to DM and AH (G1), with low clinical complications (G2), with severe clinical complications (G3), and with chronic kidney disease (G4) arised from DM and AH. It has been used a dispersive Raman spectrometer (830nm, 250mW, 20s accumulation). In the spectra of urine it was identified Raman peaks at 680cm-1 (creatinine), 1004cm-1 (urea) and 1128cm-1 (glucose). The results revealed that G2, G3 and G4 presented the creatinine peak with lower intensity than G1 (p < 0.05). It was observed that G2, G3 and G4 showed lower intensity of the urea peak compared to G1 (p < 0.05) and G4 showed lower intensity compared to G2 and G3 (p < 0.05). Despite not significant, the glucose peak showed lower intensity in G1 when compared to the other groups. A model for classification of groups according to clinical criteria, using Sparse Multinomial Logistic Regression, taking as inputs the intensities of creatine, urea and glucose peaks allowed correct classification of 88.9% for G1, 36.8% for G2, 43.8% for G3 and 84.2% for G4. These results demonstrated the possibility of obtaining diagnostic information for complications of kidney disease associated to DM and AH, particularly the renal failure.
Ghost hunting—an assessment of ghost particle detection and removal methods for tomographic-PIV
NASA Astrophysics Data System (ADS)
Elsinga, G. E.; Tokgoz, S.
2014-08-01
This paper discusses and compares several methods, which aim to remove spurious peaks, i.e. ghost particles, from the volume intensity reconstruction in tomographic-PIV. The assessment is based on numerical simulations of time-resolved tomographic-PIV experiments in linear shear flows. Within the reconstructed volumes, intensity peaks are detected and tracked over time. These peaks are associated with particles (either ghosts or actual particles) and are characterized by their peak intensity, size and track length. Peak intensity and track length are found to be effective in discriminating between most ghosts and the actual particles, although not all ghosts can be detected using only a single threshold. The size of the reconstructed particles does not reveal an important difference between ghosts and actual particles. The joint distribution of peak intensity and track length however does, under certain conditions, allow a complete separation of ghosts and actual particles. The ghosts can have either a high intensity or a long track length, but not both combined, like all the actual particles. Removing the detected ghosts from the reconstructed volume and performing additional MART iterations can decrease the particle position error at low to moderate seeding densities, but increases the position error, velocity error and tracking errors at higher densities. The observed trends in the joint distribution of peak intensity and track length are confirmed by results from a real experiment in laminar Taylor-Couette flow. This diagnostic plot allows an estimate of the number of ghosts that are indistinguishable from the actual particles.
Thermoluminescence solid-state nanodosimetry—the peak 5A/5 dosemeter
Fuks, E.; Horowitz, Y. S.; Horowitz, A.; Oster, L.; Marino, S.; Rainer, M.; Rosenfeld, A.; Datz, H.
2011-01-01
The shape of composite peak 5 in the glow curve of LiF:Mg,Ti (TLD-100) following 90Sr/90Y beta irradiation, previously demonstrated to be dependent on the cooling rate used in the 400°C pre-irradiation anneal, is shown to be dependent on ionisation density in both naturally cooled and slow-cooled samples. Following heavy-charged particle high-ionisation density (HID) irradiation, the temperature of composite peak 5 decreases by ∼5°C and the peak becomes broader. This behaviour is attributed to an increase in the relative intensity of peak 5a (a low-temperature satellite of peak 5). The relative intensity of peak 5a is estimated using a computerised glow curve deconvolution code based on first-order kinetics. The analysis uses kinetic parameters for peaks 4 and 5 determined from ancillary measurements resulting in nearly ‘single-glow peak’ curves for both the peaks. In the slow-cooled samples, owing to the increased relative intensity of peak 5a compared with the naturally cooled samples, the precision of the measurement of the 5a/5 intensity ratio is found to be ∼15 % (1 SD) compared with ∼25 % for the naturally cooled samples. The ratio of peak 5a/5 in the slow-cooled samples is found to increase systematically and gradually through a variety of radiation fields from a minimum value of 0.13±0.02 for 90Sr/90Y low-ionisation density irradiations to a maximum value of ∼0.8 for 20 MeV Cu and I ion HID irradiations. Irradiation by low-energy electrons of energy 0.1–1.5 keV results in values between 1.27 and 0.95, respectively. The increasing values of the ratio of peak 5a/5 with increasing ionisation density demonstrate the viability of the concept of the peak 5a/5 nanodosemeter and its potential in the measurement of average ionisation density in a ‘nanoscopic’ mass containing the trapping centre/luminescent centre spatially correlated molecule giving rise to composite peak 5. PMID:21149323
Soft X-Ray Absorption Spectroscopy of High-Abrasion-Furnace Carbon Black
DOE Office of Scientific and Technical Information (OSTI.GOV)
Muramatsu, Yasuji; Harada, Ryusuke; Gullikson, Eric M.
2007-02-02
The soft x-ray absorption spectra of high-abrasion-furnace carbon black were measured to obtain local-structure/chemical-states information of the primary particles and/or crystallites. The soft x-ray absorption spectral features of carbon black represent broader {pi}* and {sigma}* peak structures compared to highly oriented pyrolytic graphite (HOPG). The subtracted spectra between the carbon black and HOPG, (carbon black) - (HOPG), show double-peak structures on both sides of the {pi}* peak. The lower-energy peak, denoted as the 'pre-peak', in the subtracted spectra and the {pi}*/{sigma}* peak intensity ratio in the absorption spectra clearly depend on the specific surface area by nitrogen adsorption (NSA). Therefore,more » it is concluded that the pre-peak intensity and the {pi}*/{sigma}* ratio reflect the local graphitic structure of carbon black.« less
Endurance Exercise in Hypoxia, Hyperoxia and Normoxia: Mitochondrial and Global Adaptations.
Przyklenk, Axel; Gutmann, Boris; Schiffer, Thorsten; Hollmann, Wildor; Strueder, Heiko K; Bloch, Wilhelm; Mierau, Andreas; Gehlert, Sebastian
2017-07-01
We hypothesized short-term endurance exercise (EN) in hypoxia (HY) to exert decreased mitochondrial adaptation, peak oxygen consumption (VO 2peak ) and peak power output (PPO) compared to EN in normoxia (NOR) and hyperoxia (PER). 11 male subjects performed repeated unipedal cycling EN in HY, PER, and NOR over 4 weeks in a cross-over design. VO 2peak , PPO, rate of perceived exertion (RPE) and blood lactate (Bla) were determined pre- and post-intervention to assess physiological demands and adaptation. Skeletal muscle biopsies were collected to determine molecular mitochondrial signaling and adaptation. Despite reduced exercise intensity (P<0.05), increased Bla and RPE levels in HY revealed higher metabolic load compared to PER (P<0.05) and NOR (n.s.). PPO increased in all groups (P<0.05) while VO 2peak and mitochondrial signaling were unchanged (P>0.05). Electron transport chain complexes tended to increase in all groups with the highest increase in HY (n.s.). EN-induced mitochondrial adaptability and exercise capacity neither decreased significantly in HY nor increased in PER compared to NOR. Despite decreased exercise intensity, short term EN under HY may not necessarily impair mitochondrial adaptation and exercise capacity while PER does not augment adaptation. HY might strengthen adaptive responses under circumstances when absolute training intensity has to be reduced. © Georg Thieme Verlag KG Stuttgart · New York.
Armstrong, Craig; Samuel, Jake; Yarlett, Andrew; Cooper, Stephen-Mark; Stembridge, Mike; Stöhr, Eric J.
2016-01-01
Increased left ventricular (LV) twist and untwisting rate (LV twist mechanics) are essential responses of the heart to exercise. However, previously a large variability in LV twist mechanics during exercise has been observed, which complicates the interpretation of results. This study aimed to determine some of the physiological sources of variability in LV twist mechanics during exercise. Sixteen healthy males (age: 22 ± 4 years, V˙O2peak: 45.5 ± 6.9 ml∙kg-1∙min-1, range of individual anaerobic threshold (IAT): 32–69% of V˙O2peak) were assessed at rest and during exercise at: i) the same relative exercise intensity, 40%peak, ii) at 2% above IAT, and, iii) at 40%peak with hypoxia (40%peak+HYP). LV volumes were not significantly different between exercise conditions (P > 0.05). However, the mean margin of error of LV twist was significantly lower (F2,47 = 2.08, P < 0.05) during 40%peak compared with IAT (3.0 vs. 4.1 degrees). Despite the same workload and similar LV volumes, hypoxia increased LV twist and untwisting rate (P < 0.05), but the mean margin of error remained similar to that during 40%peak (3.2 degrees, P > 0.05). Overall, LV twist mechanics were linearly related to rate pressure product. During exercise, the intra-individual variability of LV twist mechanics is smaller at the same relative exercise intensity compared with IAT. However, the absolute magnitude (degrees) of LV twist mechanics appears to be associated with the prevailing rate pressure product. Exercise tests that evaluate LV twist mechanics should be standardised by relative exercise intensity and rate pressure product be taken into account when interpreting results. PMID:27100099
Armstrong, Craig; Samuel, Jake; Yarlett, Andrew; Cooper, Stephen-Mark; Stembridge, Mike; Stöhr, Eric J
2016-01-01
Increased left ventricular (LV) twist and untwisting rate (LV twist mechanics) are essential responses of the heart to exercise. However, previously a large variability in LV twist mechanics during exercise has been observed, which complicates the interpretation of results. This study aimed to determine some of the physiological sources of variability in LV twist mechanics during exercise. Sixteen healthy males (age: 22 ± 4 years, [Formula: see text]O2peak: 45.5 ± 6.9 ml∙kg-1∙min-1, range of individual anaerobic threshold (IAT): 32-69% of [Formula: see text]O2peak) were assessed at rest and during exercise at: i) the same relative exercise intensity, 40%peak, ii) at 2% above IAT, and, iii) at 40%peak with hypoxia (40%peak+HYP). LV volumes were not significantly different between exercise conditions (P > 0.05). However, the mean margin of error of LV twist was significantly lower (F2,47 = 2.08, P < 0.05) during 40%peak compared with IAT (3.0 vs. 4.1 degrees). Despite the same workload and similar LV volumes, hypoxia increased LV twist and untwisting rate (P < 0.05), but the mean margin of error remained similar to that during 40%peak (3.2 degrees, P > 0.05). Overall, LV twist mechanics were linearly related to rate pressure product. During exercise, the intra-individual variability of LV twist mechanics is smaller at the same relative exercise intensity compared with IAT. However, the absolute magnitude (degrees) of LV twist mechanics appears to be associated with the prevailing rate pressure product. Exercise tests that evaluate LV twist mechanics should be standardised by relative exercise intensity and rate pressure product be taken into account when interpreting results.
Acute effects of high- and low-intensity exercise bouts on leukocyte counts.
Neves, Pedro Rogério Da Silva; Tenório, Thiago Ricardo Dos Santos; Lins, Tatiana Acioli; Muniz, Maria Tereza Cartaxo; Pithon-Curi, Tânia Cristina; Botero, João Paulo; Do Prado, Wagner Luiz
2015-06-01
It is widely accepted that physical exercise may bring about changes in the immune system. Even acute bouts of exercise can alter the number and function of leukocytes, but the degree of white blood cell trafficking depends on the intensity and duration of exercise. The aim of this study was to analyze the acute and short-term effects of exercise intensity on leukocyte counts and leukocyte subsets. Nine physically healthy, active young males (21.0 ± 1.9 years) underwent three experimental trials: high exercise intensity [80% peak oxygen consumption (VO 2peak )], low exercise intensity (40% VO 2peak ), and the control condition (no exercise). Blood samples were collected prior to exercise, immediately after exercise, and 2 hours after exercise. Two-way analysis of variance for repeated measures was used to evaluate differences between the trials and the time-points, and to compare times within trials. There was a greater increase in the leukocyte count after high-intensity exercise, compared to the control condition ( p < 0.01) and low-intensity exercise ( p < 0.01). This effect was still present 2 hours after passive recovery ( p < 0.01). When the same participants were submitted to different exercise intensities, the acute and short-term effects of exercise on white blood cells were intensity-dependent immediately after exercise (i.e., lymphocytosis and monocytosis) and 2 hours after passive recovery (i.e., neutrophilia).
Laryngeal Aerodynamics in Healthy Older Adults and Adults with Parkinson's Disease
ERIC Educational Resources Information Center
Matheron, Deborah; Stathopoulos, Elaine T.; Huber, Jessica E.; Sussman, Joan E.
2017-01-01
Purpose: The present study compared laryngeal aerodynamic function of healthy older adults (HOA) to adults with Parkinson's disease (PD) while speaking at a comfortable and increased vocal intensity. Method: Laryngeal aerodynamic measures (subglottal pressure, peak-to-peak flow, minimum flow, and open quotient [OQ]) were compared between HOAs and…
A wavelet-based Gaussian method for energy dispersive X-ray fluorescence spectrum.
Liu, Pan; Deng, Xiaoyan; Tang, Xin; Shen, Shijian
2017-05-01
This paper presents a wavelet-based Gaussian method (WGM) for the peak intensity estimation of energy dispersive X-ray fluorescence (EDXRF). The relationship between the parameters of Gaussian curve and the wavelet coefficients of Gaussian peak point is firstly established based on the Mexican hat wavelet. It is found that the Gaussian parameters can be accurately calculated by any two wavelet coefficients at the peak point which has to be known. This fact leads to a local Gaussian estimation method for spectral peaks, which estimates the Gaussian parameters based on the detail wavelet coefficients of Gaussian peak point. The proposed method is tested via simulated and measured spectra from an energy X-ray spectrometer, and compared with some existing methods. The results prove that the proposed method can directly estimate the peak intensity of EDXRF free from the background information, and also effectively distinguish overlap peaks in EDXRF spectrum.
Kong, Zhaowei; Sun, Shengyan; Liu, Min
2016-01-01
This study was to determine the effects of five-week high-intensity interval training (HIIT) on cardiorespiratory fitness, body composition, blood glucose, and relevant systemic hormones when compared to moderate-intensity continuous training (MICT) in overweight and obese young women. Methods. Eighteen subjects completed 20 sessions of HIIT or MICT for five weeks. HIIT involved 60 × 8 s cycling at ~90% of peak oxygen consumption (V˙O2peak) interspersed with 12 s recovery, whereas MICT involved 40-minute continuous cycling at 65% of V˙O2peak. V˙O2peak, body composition, blood glucose, and fasting serum hormones, including leptin, growth hormone, testosterone, cortisol, and fibroblast growth factor 21, were measured before and after training. Results. Both exercise groups achieved significant improvements in V˙O2peak (+7.9% in HIIT versus +11.7% in MICT) and peak power output (+13.8% in HIIT versus +21.9% in MICT) despite no training effects on body composition or the relevant systemic hormones. Blood glucose tended to be decreased after the intervention (p = 0.062). The rating of perceived exertion in MICT was higher than that in HIIT (p = 0.042). Conclusion. Compared with MICT, short-term HIIT is more time-efficient and is perceived as being easier for improving cardiorespiratory fitness and fasting blood glucose for overweight and obese young women. PMID:27774458
Temperature dependence of sapphire fiber Raman scattering
Liu, Bo; Yu, Zhihao; Tian, Zhipeng; ...
2015-04-27
Anti-Stokes Raman scattering in sapphire fiber has been observed for the first time. Temperature dependence of Raman peaks’ intensity, frequency shift, and linewidth were also measured. Three anti-Stokes Raman peaks were observed at temperatures higher than 300°C in a 0.72-m-long sapphire fiber excited by a second-harmonic Nd YAG laser. The intensity of anti-Stokes peaks are comparable to that of Stokes peaks when the temperature increases to 1033°C. We foresee the combination of sapphire fiber Stokes and anti-Stokes measurement in use as a mechanism for ultrahigh temperature sensing.
Villelabeitia-Jaureguizar, Koldobika; Vicente-Campos, Davinia; Senen, Alejandro Berenguel; Jiménez, Verónica Hernández; Garrido-Lestache, María Elvira Barrios; Chicharro, Jose López
2017-10-01
Heart rate recovery (HRR) has been considered a prognostic and mortality indicator in both healthy and coronary patients. Physical exercise prescription has shown improvements in VO 2 peak and HRR, but most of the studies have been carried out applying continuous training at a moderate intensity, being very limited the use of protocols of high intensity interval training in coronary patients. We aimed to compare the effects of a moderate continuous training (MCT) versus a high intensity interval training (HIIT) programme on VO 2 peak and HRR. Seventy three coronary patients were assigned to either HIIT or MCT groups for 8weeks. Incremental exercise tests in a cycloergometer were performed to obtain VO 2 peak data and heart rate was monitored during and after the exercise test to obtain heart rate recovery data. Both exercise programmes significantly increase VO 2 peak with a higher increase in the HIIT group (HIIT: 4.5±4.46ml/kg/min vs MCT: 2.46±3.57ml/kg/min; p=0.039). High intensity interval training resulted in a significantly increase in HRR at the first and second minute of the recovery phase (15,44±7,04 vs 21,22±6,62, p<0,0001 and 23,73±9,64 vs 31,52±8,02, p<0,0001, respectively). The results of our research show that the application of HIIT to patients with chronic ischemic heart disease of low risk resulted in an improvement in VO 2 peak, and also improvements in post-exercise heart-rate recovery, compared with continuous training. Copyright © 2017 Elsevier B.V. All rights reserved.
Improving Precision, Maintaining Accuracy, and Reducing Acquisition Time for Trace Elements in EPMA
NASA Astrophysics Data System (ADS)
Donovan, J.; Singer, J.; Armstrong, J. T.
2016-12-01
Trace element precision in electron probe micro analysis (EPMA) is limited by intrinsic random variation in the x-ray continuum. Traditionally we characterize background intensity by measuring on either side of the emission line and interpolating the intensity underneath the peak to obtain the net intensity. Alternatively, we can measure the background intensity at the on-peak spectrometer position using a number of standard materials that do not contain the element of interest. This so-called mean atomic number (MAN) background calibration (Donovan, et al., 2016) uses a set of standard measurements, covering an appropriate range of average atomic number, to iteratively estimate the continuum intensity for the unknown composition (and hence average atomic number). We will demonstrate that, at least for materials with a relatively simple matrix such as SiO2, TiO2, ZrSiO4, etc. where one may obtain a matrix matched standard for use in the so called "blank correction", we can obtain trace element accuracy comparable to traditional off-peak methods, and with improved precision, in about half the time. Donovan, Singer and Armstrong, A New EPMA Method for Fast Trace Element Analysis in Simple Matrices ", American Mineralogist, v101, p1839-1853, 2016 Figure 1. Uranium concentration line profiles from quantitative x-ray maps (20 keV, 100 nA, 5 um beam size and 4000 msec per pixel), for both off-peak and MAN background methods without (a), and with (b), the blank correction applied. We see precision significantly improved compared with traditional off-peak measurements while, in this case, the blank correction provides a small but discernable improvement in accuracy.
Schoenmakers, Patrick; Reed, Kate; Van Der Woude, Luc; Hettinga, Florentina J.
2016-01-01
Introduction: In lower body endurance training, quantities of both moderate intensity continuous training (MICT) and high intensity interval training (HIIT) can lead to an improved physiological capacity and performance. Limited research is available regarding the endurance and muscular capacity of the upper body, and how training contributes to improvements in performance capacity is still unknown. The aim of the current study was to evaluate the effects of HIIT and MICT on the physiological capacity and handcycling performance of able-bodied men in a well-controlled laboratory setting. Methods: Twenty four recreationally active men (22 ± 2 years; 1.84 ± 0.04 m; 79 ± 10 kg) were matched on incremental handcycling pre-test performance (peakPO) and then randomly assigned to HIIT, MICT, or a non-training control group (CON, 3 × n = 8). Participants in HIIT completed 14 interval training sessions, performing 4 × 4 min intervals at 85% heart rate reserve (%HRR), and seven continuous training sessions at 55 %HRR (every 2nd training session of the week). Participants in MICT performed 21 training sessions of 30 min at 55 %HRR. After the intervention, changes in peak oxygen uptake (peakVO2) and peak power output (peakPO) were compared within and between HIIT, MICT and CON. Results: The average external training load per training session did not differ between MICT and HIIT (p = 0.713). Improvements after HIIT in peakVO2 (22.2 ± 8.1%) and peakPO (47.1 ± 20.7%) were significantly larger compared with MICT and CON (p < 0.001). Improvements after MICT in peakVO2 (10.7 ± 12.9%) and peakPO (32.2 ± 8.1%) were higher compared to CON (p < 0.001). Higher improvement after HIIT occurred despite training 22% less time than MICT. No significant changes were found in CON. Discussion: As in lower body endurance sports, HIIT proved to be very effective in improving the physiological and performance capacity of upper body exercise. Whilst physiological capacity in both training groups improved significantly compared with CON, the present study shows that peakVO2 and peakPO improved more after HIIT than after MICT in able-bodied men. It is advised to include HIIT into training regimes of recreational and competitive handcyclists to improve the upper body endurance capacity. PMID:28066268
Schoenmakers, Patrick; Reed, Kate; Van Der Woude, Luc; Hettinga, Florentina J
2016-01-01
Introduction: In lower body endurance training, quantities of both moderate intensity continuous training (MICT) and high intensity interval training (HIIT) can lead to an improved physiological capacity and performance. Limited research is available regarding the endurance and muscular capacity of the upper body, and how training contributes to improvements in performance capacity is still unknown. The aim of the current study was to evaluate the effects of HIIT and MICT on the physiological capacity and handcycling performance of able-bodied men in a well-controlled laboratory setting. Methods: Twenty four recreationally active men (22 ± 2 years; 1.84 ± 0.04 m; 79 ± 10 kg) were matched on incremental handcycling pre-test performance (peakPO) and then randomly assigned to HIIT, MICT, or a non-training control group (CON, 3 × n = 8). Participants in HIIT completed 14 interval training sessions, performing 4 × 4 min intervals at 85% heart rate reserve (%HRR), and seven continuous training sessions at 55 %HRR (every 2nd training session of the week). Participants in MICT performed 21 training sessions of 30 min at 55 %HRR. After the intervention, changes in peak oxygen uptake (peakVO 2 ) and peak power output (peakPO) were compared within and between HIIT, MICT and CON. Results: The average external training load per training session did not differ between MICT and HIIT ( p = 0.713). Improvements after HIIT in peakVO 2 (22.2 ± 8.1%) and peakPO (47.1 ± 20.7%) were significantly larger compared with MICT and CON ( p < 0.001). Improvements after MICT in peakVO 2 (10.7 ± 12.9%) and peakPO (32.2 ± 8.1%) were higher compared to CON ( p < 0.001). Higher improvement after HIIT occurred despite training 22% less time than MICT. No significant changes were found in CON. Discussion: As in lower body endurance sports, HIIT proved to be very effective in improving the physiological and performance capacity of upper body exercise. Whilst physiological capacity in both training groups improved significantly compared with CON, the present study shows that peakVO 2 and peakPO improved more after HIIT than after MICT in able-bodied men. It is advised to include HIIT into training regimes of recreational and competitive handcyclists to improve the upper body endurance capacity.
Arm and Intensity-Matched Leg Exercise Induce Similar Inflammatory Responses.
Leicht, Christof A; Paulson, Thomas A W; Goosey-Tolfrey, Victoria L; Bishop, Nicolette C
2016-06-01
The amount of active muscle mass can influence the acute inflammatory response to exercise, associated with reduced risk for chronic disease. This may affect those restricted to upper body exercise, for example, due to injury or disability. The purpose of this study was to compare the inflammatory responses for arm exercise and intensity-matched leg exercise. Twelve male individuals performed three 45-min constant load exercise trials after determination of peak oxygen uptake for arm exercise (V˙O2peak A) and cycling (V˙O2peak C): 1) arm cranking exercise at 60% V˙O2peak A, 2) moderate cycling at 60% V˙O2peak C, and 3) easy cycling at 60% V˙O2peak A. Cytokine, adrenaline, and flow cytometric analysis of monocyte subsets were performed before and up to 4 h postexercise. Plasma IL-6 increased from resting concentrations in all trials; however, postexercise concentrations were higher for arm exercise (1.73 ± 1.04 pg·mL) and moderate cycling (1.73 ± 0.95 pg·mL) compared with easy cycling (0.87 ± 0.41 pg·mL; P < 0.04). Similarly, the plasma IL-1ra concentration in the recovery period was higher for arm exercise (325 ± 139 pg·mL) and moderate cycling (316 ± 128 pg·mL) when compared with easy cycling (245 ± 77 pg·mL, P < 0.04). Arm exercise and moderate cycling induced larger increases in monocyte numbers and larger increases of the classical monocyte subset in the recovery period than easy cycling (P < 0.05). The postexercise adrenaline concentration was lowest for easy cycling (P = 0.04). Arm exercise and cycling at the same relative exercise intensity induces a comparable acute inflammatory response; however, cycling at the same absolute oxygen uptake as arm exercise results in a blunted cytokine, monocyte, and adrenaline response. Relative exercise intensity appears to be more important to the acute inflammatory response than modality, which is of major relevance for populations restricted to upper body exercise.
Energy Flux in the Cochlea: Evidence Against Power Amplification of the Traveling Wave.
van der Heijden, Marcel; Versteegh, Corstiaen P C
2015-10-01
Traveling waves in the inner ear exhibit an amplitude peak that shifts with frequency. The peaking is commonly believed to rely on motile processes that amplify the wave by inserting energy. We recorded the vibrations at adjacent positions on the basilar membrane in sensitive gerbil cochleae and tested the putative power amplification in two ways. First, we determined the energy flux of the traveling wave at its peak and compared it to the acoustic power entering the ear, thereby obtaining the net cochlear power gain. For soft sounds, the energy flux at the peak was 1 ± 0.6 dB less than the middle ear input power. For more intense sounds, increasingly smaller fractions of the acoustic power actually reached the peak region. Thus, we found no net power amplification of soft sounds and a strong net attenuation of intense sounds. Second, we analyzed local wave propagation on the basilar membrane. We found that the waves slowed down abruptly when approaching their peak, causing an energy densification that quantitatively matched the amplitude peaking, similar to the growth of sea waves approaching the beach. Thus, we found no local power amplification of soft sounds and strong local attenuation of intense sounds. The most parsimonious interpretation of these findings is that cochlear sensitivity is not realized by amplifying acoustic energy, but by spatially focusing it, and that dynamic compression is realized by adjusting the amount of dissipation to sound intensity.
Observation of the Intrinsic Bandgap Behavior in As-Grown Epitaxial Twisted Graphene (Postprint)
2015-01-06
the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this...intensity, which becomes compar able to that of G band intensity and is now a symmetric , single Lorentzian peak. The third difference is the 2D band peak...spectrum with SiC signal subtracted. (c,d) Variation of Raman C60/GF FLG spectra as a function of C60 deposition time . A single Lorentzian 2D band was
Smart, Neil A
2013-01-01
BACKGROUND: Peak oxygen consumption (VO2) is the gold standard measure of cardiorespiratory fitness and a reliable predictor of survival in chronic heart failure patients. Furthermore, any form of physical training usually improves cardiorespiratory fitness, although the magnitude of improvement in peak VO2 may vary across different training prescriptions. OBJECTIVE: To quantify, and subsequently rank, the magnitude of improvement in peak VO2 for different physical training prescriptions using data from published meta-analyses and randomized controlled trials. METHODS: Prospective randomized controlled parallel trials and meta-analyses of exercise training in chronic heart failure patients that provided data on change in peak VO2 for nine a priori comparative analyses were examined. RESULTS: All forms of physical training were beneficial, although the improvement in peak VO2 varied with modality. High-intensity interval exercise yielded the largest increase in peak VO2, followed in descending order by moderate-intensity aerobic exercise, functional electrical stimulation, inspiratory muscle training, combined aerobic and resistance training, and isolated resistance training. With regard to setting, the present study was unable to determine whether outpatient or unsupervised home exercise provided greater benefits in terms of peak VO2 improvment. CONCLUSIONS: Interval exercise is not suitable for all patients, especially the high-intensity variety; however, when indicated, this form of exercise should be adopted to optimize peak VO2 adaptations. Other forms of activity, such as functional electrical stimulation, may be more appropriate for patients who are not capable of high-intensity interval training, especially for severely deconditioned patients who are initially unable to exercise. PMID:24294043
Features of an annealing-induced thermoluminescence peak in α-Al2O3:C,Mg
NASA Astrophysics Data System (ADS)
Kalita, J. M.; Chithambo, M. L.
2017-08-01
We report the thermoluminescence glow curves of beta irradiated single crystal α-Al2O3:C,Mg after annealing at 700 and 900 °C. A glow curve measured at 1 °C/s from samples irradiated to 1 Gy following annealing at 700 and 900 °C shows a high intensity peak at 163 °C and seven secondary peaks of weaker intensity at 43, 73, 100, 195, 280, 329 and 370 °C. Comparing the position of the peaks in the annealed samples with those in an un-annealed one, it is observed that the peak at 100 °C appears only after annealing at and above 700 °C. Kinetic analysis of this annealing-induced peak was carried out using the initial rise, whole glow peak, peak shape, curve fitting and variable heating rate methods. The order of kinetics of the peak was determined as first order using various methods including the Tm-Tstop technique and the dependence of Tm on irradiation dose. The activation energy of the peak is about 1.01 eV and the frequency factor of the order of 1012 s-1. The peak was found to be affected by thermal quenching in analysis based on change of peak intensity with heating rate. The activation energy of thermal quenching was evaluated as 1.06 ± 0.08 eV. We speculate that the annealing-induced peak is due to formation of a new electron trap after destruction of the F22+(2 Mg) centre when the sample is annealed at 700 °C. The annealing-induced peak fades with storage between irradiation and measurement. It was also concluded that electrons from traps corresponding to secondary peaks get re-trapped at the main electron trap.
Leddy, Abigail L; Connolly, Mark; Holleran, Carey L; Hennessy, Patrick W; Woodward, Jane; Arena, Ross A; Roth, Elliot J; Hornby, T George
2016-10-01
Impairments in metabolic capacity and economy (O2cost) are hallmark characteristics of locomotor dysfunction following stroke. High-intensity (aerobic) training has been shown to improve peak oxygen consumption in this population, with fewer reports of changes in O2cost. However, particularly in persons with subacute stroke, inconsistent gains in walking function are observed with minimal associations with gains in metabolic parameters. The purpose of this study was to evaluate changes in aerobic exercise performance in participants with subacute stroke following high-intensity variable stepping training as compared with conventional therapy. A secondary analysis was performed on data from a randomized controlled trial comparing high-intensity training with conventional interventions, and from the pilot study that formed the basis for the randomized controlled trial. Participants 1 to 6 months poststroke received 40 or fewer sessions of high-intensity variable stepping training (n = 21) or conventional interventions (n = 12). Assessments were performed at baseline (BSL), posttraining, and 2- to 3-month follow-up and included changes in submaximal (Equation is included in full-text article.)O2 ((Equation is included in full-text article.)O2submax) and O2cost at fastest possible treadmill speeds and peak speeds at BSL testing. Significant improvements were observed in (Equation is included in full-text article.)O2submax with less consistent improvements in O2cost, although individual responses varied substantially. Combined changes in both (Equation is included in full-text article.)O2submax and (Equation is included in full-text article.)O2 at matched peak BSL speeds revealed stronger correlations to improvements in walking function as compared with either measure alone. High-intensity stepping training may elicit significant improvements in (Equation is included in full-text article.)O2submax, whereas changes in both peak capacity and economy better reflect gains in walking function. Providing high-intensity training to improve locomotor and aerobic exercise performance may increase the efficiency of rehabilitation sessions.Video Abstract available for more insights from the authors (see Supplemental Digital Content, http://links.lww.com/JNPT/A142).
McCarthy, Avina; Mulligan, James; Egaña, Mikel
2016-11-01
A brief cold water immersion between 2 continuous high-intensity exercise bouts improves the performance of the latter compared with passive recovery in the heat. We investigated if this effect is apparent in normothermic conditions (∼19 °C), employing an intermittent high-intensity exercise designed to reflect the work performed at the high-intensity domain in team sports. Fifteen young active men completed 2 exhaustive cycling protocols (Ex1 and Ex2: 12 min at 85% ventilatory threshold (VT) and then an intermittent exercise alternating 30-s at 40% peak power (P peak ) and 30 s at 90% P peak to exhaustion) separated by 15 min of (i) passive rest, (ii) 5-min cold-water immersion at 8 °C, and (iii) 10-min cold-water immersion at 8 °C. Core temperature, heart rate, rates of perceived exertion, and oxygen uptake kinetics were not different during Ex1 among conditions. Time to failure during the intermittent exercise was significantly (P < 0.05) longer during Ex2 following the 5- and 10-min cold-water immersions (7.2 ± 3.5 min and 7.3 ± 3.3 min, respectively) compared with passive rest (5.8 ± 3.1 min). Core temperature, heart rate, and rates of perceived exertion were significantly (P < 0.05) lower during most periods of Ex2 after both cold-water immersions compared with passive rest. The time constant of phase II oxygen uptake response during the 85% VT bout of Ex2 was not different among the 3 conditions. A postexercise, 5- to 10-min cold-water immersion increases subsequent intermittent high-intensity exercise compared with passive rest in normothermia due, at least in part, to reductions in core temperature, circulatory strain, and effort perception.
Laser induced fluorescence of dental caries
NASA Technical Reports Server (NTRS)
Albin, S.; Byvik, C. E.; Buoncristiani, A. M.
1988-01-01
Significant differences between the optical spectra taken from sound regions of teeth and carious regions have been observed. These differences appear both in absorption and in laser induced fluorescence spectra. Excitation by the 488 nm line of an argon ion laser beam showed a peak in the emission intensity around 553 nm for the sound dental material while the emission peak from the carious region was red-shifted by approximately 40 nm. The relative absorption of carious region was significantly higher at 488 nm; however its fluorescence intensity peak was lower by an order of magnitude compared to the sound tooth. Implications of these results for a safe, reliable and early detection of dental caries are discussed.
NASA Technical Reports Server (NTRS)
Downs, Meghan E.; Buxton, Roxanne; Moore, Alan; Ploutz-Snyder, Robert; Ploutz-Snyder, Lori
2014-01-01
There is considerable variability among astronauts with respect to changes in maximal aerobic capacity (VO2peak) during International Space Station (ISS) missions, ranging from a 5% increase to 30% decline. Individual differences may be due to in-flight aerobic exercise time and intensity. PURPOSE: To evaluate the effects of in-flight aerobic exercise time and intensity on change in VO2peak during ISS missions. METHODS: Astronauts (N=11) performed peak cycle tests approx 60 days before flight (L-60), on flight day (FD) approx 14, and every approx 30 days thereafter. Metabolic gas analysis and heart rate (HR) were measured continuously during the test using the portable pulmonary function system. HR and duration of each in-flight cycle ergometer and treadmill (TM) session were recorded and averaged in time segments corresponding to each peak test. Mixed effects linear regression with exercise mode (TM or cycle) as a categorical variable was used to assess the contributions of exercise intensity (%time >70% peak HR or %time >90% peak HR) and time (min/wk), adjusted for body weight, on %change in VO2peak during the mission, and incorporating the repeated-measures experimental design. RESULTS: 110 observations were included in the model (4-6 peak cycle tests per astronaut, 2 exercise devices). VO2peak was reduced from preflight throughout the mission (FD14: 13+/-13% and FD 105: 8+/-10%). Exercise intensity (%peak HR: FD14=66+/-14; FD105=75+/-8) and time (min/wk: FD14=82+/-46; FD105=158+/-40) increased during flight. The models showed main effects for exercise time and intensity with no interactions between time, intensity, and device (70% peak HR: time [z-score=2.39; P=0.017], intensity [z-score=3.51; P=0.000]; 90% peak HR: time [zscore= 3.31; P=0.001], intensity [z-score=2.24; P=0.025]). CONCLUSION: Exercise time and intensity independently contribute to %change in VO2peak during ISS missions, indicating that there are minimal values for exercise time and intensity required to maintain VO2peak. As the FD105 average exercise intensity and time did not prevent a decline in VO2peak from preflight, astronauts' exercise prescriptions should target at least 160 min of weekly aerobic exercise at an average above 75% peak HR with increased time at intensities above 90% of peak HR starting early in the mission.
Sokolov, V.; Wald, D.J.
2002-01-01
We compare two methods of seismic-intensity estimation from ground-motion records for the two recent strong earthquakes: the 1999 (M 7.1) Hector Mine, California, and the 1999 (M 7.6) Chi-Chi, Taiwan. The first technique utilizes the peak ground acceleration (PGA) and velocity (PGV), and it is used for rapid generation of the instrumental intensity map in California. The other method is based on the revised relationships between intensity and Fourier amplitude spectrum (FAS). The results of using the methods are compared with independently observed data and between the estimations from the records. For the case of the Hector Mine earthquake, the calculated intensities in general agree with the observed values. For the case of the Chi-Chi earthquake, the areas of maximum calculated intensity correspond to the areas of the greatest damage and highest number of fatalities. However, the FAS method producees higher-intensity values than those of the peak amplitude method. The specific features of ground-motion excitation during the large, shallow, thrust earthquake may be considered a reason for the discrepancy. The use of PGA and PGV is simple; however, the use of FAS provides a natural consideration of site amplification by means of generalized or site-specific spectral ratios. Because the calculation of seismic-intensity maps requires rapid processing of data from a large network, it is very practical to generate a "first-order" map from the recorded peak motions. Then, a "second-order" map may be compiled using an amplitude-spectra method on the basis of available records and numerical modeling of the site-dependent spectra for the regions of sparse station spacing.
Ritti-Dias, Raphael Mendes; de Moraes Forjaz, Cláudia Lúcia; Cucato, Gabriel Grizzo; Costa, Luis Augusto Riani; Wolosker, Nelson; de Fátima Nunes Marucci, Maria
2009-01-01
Walking training is considered as the first treatment option for patients with peripheral arterial disease and intermittent claudication (IC). Walking exercise has been prescribed for these patients by relative intensity of peak oxygen uptake (VO2peak), ranging from 40% to 70% VO2peak, or pain threshold (PT). However, the relationship between these methods and anaerobic threshold (AT), which is considered one of the best metabolic markers for establishing training intensity, has not been analyzed. Thus, the aim of this study was to compare, in IC patients, the physiological responses at exercise intensities usually prescribed for training (% VO2peak or % PT) with the ones observed at AT. Thirty-three IC patients performed maximal graded cardiopulmonary treadmill test to assess exercise tolerance. During the test, heart rate (HR), VO2, and systolic blood pressure were measured and responses were analyzed at the following: 40% of VO2peak; 70% of VO2peak; AT; and PT. Heart rate and VO2 at 40% and 70% of VO2peak were lower than those at AT (HR: -13 +/- 9% and -3 +/- 8%, P < .01, respectively; VO2: -52 +/- 12% and -13 +/- 15%, P < .01, respectively). Conversely, HR and VO2 at PT were slightly higher than those at AT (HR: +3 +/- 8%, P < .01; VO2: +6 +/- 15%, P = .04). None of the patients achieved the respiratory compensation point. Prescribing exercise for IC patients between 40% and 70% of VO2peak will induce a lower stimulus than that at AT, whereas prescribing exercise at PT will result in a stimulus above AT. Thus, prescribing exercise training for IC patients on the basis of PT will probably produce a greater metabolic stimulus, promoting better cardiovascular benefits.
Sound-Intensity Feedback During Running Reduces Loading Rates and Impact Peak.
Tate, Jeremiah J; Milner, Clare E
2017-08-01
Study Design Controlled laboratory study, within-session design. Background Gait retraining has been proposed as an effective intervention to reduce impact loading in runners at risk of stress fractures. Interventions that can be easily implemented in the clinic are needed. Objective To assess the immediate effects of sound-intensity feedback related to impact during running on vertical impact peak, peak vertical instantaneous loading rate, and vertical average loading rate. Methods Fourteen healthy, college-aged runners who ran at least 9.7 km/wk participated (4 male, 10 female; mean ± SD age, 23.7 ± 2.0 years; height, 1.67 ± 0.08 m; mass, 60.9 ± 8.7 kg). A decibel meter provided real-time sound-intensity feedback of treadmill running via an iPad application. Participants were asked to reduce the sound intensity of running while receiving continuous feedback for 15 minutes, while running at their self-selected preferred speed. Baseline and follow-up ground reaction force data were collected during overground running at participants' self-selected preferred running speed. Results Dependent t tests indicated a statistically significant reduction in vertical impact peak (1.56 BW to 1.13 BW, P≤.001), vertical instantaneous loading rate (95.48 BW/s to 62.79 BW/s, P = .001), and vertical average loading rate (69.09 BW/s to 43.91 BW/s, P≤.001) after gait retraining, compared to baseline. Conclusion The results of the current study support the use of sound-intensity feedback during treadmill running to immediately reduce loading rate and impact force. The transfer of within-session reductions in impact peak and loading rates to overground running was demonstrated. Decreases in loading were of comparable magnitude to those observed in other gait retraining methods. J Orthop Sports Phys Ther 2017;47(8):565-569. Epub 6 Jul 2017. doi:10.2519/jospt.2017.7275.
Bennett, Tellen D; Hayward, Kristen N; Farris, Reid W D; Ringold, Sarah; Wallace, Carol A; Brogan, Thomas V
2011-11-01
To determine whether an elevated serum ferritin level is independently associated with mortality and receipt of critical care in pediatric patients. Retrospective cohort study, open population. Seattle Children's Hospital, Seattle, WA, from September 2, 2003, to February 15, 2008. All patients tested for serum ferritin level from September 2, 2003, to August 16, 2007, with a level ≥1000 ng/mL. None. MAIN ANALYSIS: Cox regression. The predictor of interest was the patient-specific peak serum ferritin level, dichotomized a priori at 3000 ng/mL. The outcomes were mortality and intensive care unit admission. A total of 171 patients met the inclusion criteria. The observation time without death or intensive care unit admission ranged from 184 to 1621 days. The hazard ratio of death with peak ferritin of >3000 ng/mL was 4.32 (95% confidence interval 2.21-8.47, p < .001) compared to peak ferritin of 1000-3000 ng/mL. The hazard ratio of intensive care unit admission with peak ferritin of >3000 ng/mL was 2.49 (95% confidence interval 1.53-4.05, p < .001) compared to peak ferritin of 1000-3000 ng/mL. Both estimates were adjusted for bone marrow transplant, solid organ transplant, hemoglobinopathy, and existing rheumatologic disease. In this pediatric population, with serum ferritin levels of >3000 ng/mL, there was increased risk for both receipt of critical care and subsequent death.
Huan, Tao; Li, Liang
2015-01-20
Metabolomics requires quantitative comparison of individual metabolites present in an entire sample set. Unfortunately, missing intensity values in one or more samples are very common. Because missing values can have a profound influence on metabolomic results, the extent of missing values found in a metabolomic data set should be treated as an important parameter for measuring the analytical performance of a technique. In this work, we report a study on the scope of missing values and a robust method of filling the missing values in a chemical isotope labeling (CIL) LC-MS metabolomics platform. Unlike conventional LC-MS, CIL LC-MS quantifies the concentration differences of individual metabolites in two comparative samples based on the mass spectral peak intensity ratio of a peak pair from a mixture of differentially labeled samples. We show that this peak-pair feature can be explored as a unique means of extracting metabolite intensity information from raw mass spectra. In our approach, a peak-pair peaking algorithm, IsoMS, is initially used to process the LC-MS data set to generate a CSV file or table that contains metabolite ID and peak ratio information (i.e., metabolite-intensity table). A zero-fill program, freely available from MyCompoundID.org , is developed to automatically find a missing value in the CSV file and go back to the raw LC-MS data to find the peak pair and, then, calculate the intensity ratio and enter the ratio value into the table. Most of the missing values are found to be low abundance peak pairs. We demonstrate the performance of this method in analyzing an experimental and technical replicate data set of human urine metabolome. Furthermore, we propose a standardized approach of counting missing values in a replicate data set as a way of gauging the extent of missing values in a metabolomics platform. Finally, we illustrate that applying the zero-fill program, in conjunction with dansylation CIL LC-MS, can lead to a marked improvement in finding significant metabolites that differentiate bladder cancer patients and their controls in a metabolomics study of 109 subjects.
NASA Astrophysics Data System (ADS)
Li, Xiaozhou; Lin, Junxiu; Jia, Chunde; Wang, Rong
2003-12-01
In this paper, we attempt to find a valid method to distinguish gastric cancer and atrophic gastritis. Auto-fluorescence and Raman spectroscopy of laser induced (514.5 nm and 488.0 nm) was measured. The serum spectrum is different between normal and cancer. Average value of diagnosis parameter for normal serum, red shift is less than 12 nm and Raman relative intensity of peak C by 514.5 nm excited is stronger than that of 488.0 nm. To gastric cancer, its red shift of average is bigger than 12 nm and relative intensity of Raman peak C by 514.5 nm excited is weaker than that by 488.0 nm. To atrophic gastritis, the distribution state of Raman peaks is similar with normal serum and auto-fluorescence spectrum's shape is similar to that of gastric cancer. Its average Raman peak red shift is bigger than 12 nm and the relative intensity of peak C by 514.5 excited is stronger than that of by 488.0. We considered it as a criterion and got an accuracy of 85.6% for diagnosis of gastric cancer compared with the result of clinical diagnosis.
Knauert, Melissa; Jeon, Sangchoon; Murphy, Terrence E.; Yaggi, H. Klar; Pisani, Margaret A.; Redeker, Nancy S.
2016-01-01
Purpose Sound levels in the intensive care unit (ICU) are universally elevated and are believed to contribute to sleep and circadian disruption. The purpose of this study is to compare overnight ICU sound levels and peak occurrence on A- versus C-weighted scales. Materials and Methods This was a prospective observational study of overnight sound levels in 59 medical ICU patient rooms. Sound level was recorded every 10 seconds on A- and C-weighted decibel scales. Equivalent sound level (Leq) and sound peaks were reported for full and partial night periods. Results The overnight A-weighted Leq of 53.6 dBA was well above World Health Organization (WHO) recommendations; overnight C-weighted Leq was 63.1 dBC (no WHO recommendations). Peak sound occurrence ranged from 1.8 to 23.3 times per hour. Illness severity, mechanical ventilation and delirium were not associated with Leq or peak occurrence. Leq and peak measures for A- and C-weighted decibel scales were significantly different from each other. Conclusions Sound levels in the medical ICU are high throughout the night. Patient factors were not associated with Leq or peak occurrence. Significant discordance between A- and C-weighted values suggests that low frequency sound is a meaningful factor in the medical ICU environment. PMID:27546739
Panissa, Valéria L. G.; Julio, Ursula F.; França, Vanessa; Lira, Fabio S.; Hofmann, Peter; Takito, Monica Y.; Franchini, Emerson
2016-01-01
The purpose of this study was to compare sex-related responses to a self-paced all out high-intensity intermittent exercise (HIIE). 9 women and 10 men were submitted to a maximal incremental test (to determine maximum aerobic power - MAP and VO2peak), and an HIIE cycling (60x8s:12s, effort:pause). During the protocol the mean value of V̇O2 and heart rate for the entire exercise (VO2total and HRtotal) as well as the values only in the effort or pause (V̇O2effort, VO2pause and HReffort and HRpause) relative to VO2peak were measured. Anaerobic power reserve (APR), blood lactate [La] and the respiratory exchange ratio (RER) were also measured. These variables were compared between men and women using the unpaired t test. Men used greater APR (109 ± 12%MAP vs 92 ± 6%MAP) with similar V̇O2total (74 ± 7 vs 78 ± 8% VO2peak), however, when effort and pause were analysed separately, V̇O2effort (80 ± 9 vs 80 ± 5%VO2peak) was similar between sexes, while V̇O2pause was lower in men (69 ± 6% vs 77 ± 11% VO2peak, respectively). Women presented lower power decrement (30 ± 11 vs 11 ± 3%), RER (1.04 ± 0.03 vs 1.00 ± 0.02) and [La]peak (8.6 ± 0.9 vs 5.9 ± 2.3 mmol.L-1). Thus, we can conclude that men self-paced HIIE at higher APR but with the same cardiovascular/aerobic solicitation as women. Key points Men self-paced high-intensity intermittent exercise at higher intensities than women. Men utilized greater anaerobic power reserve than women. Men and women had same cardiovascular solicitation. PMID:27274678
MacInnis, Martin J.; Zacharewicz, Evelyn; Martin, Brian J.; Haikalis, Maria E.; Skelly, Lauren E.; Tarnopolsky, Mark A.; Murphy, Robyn M.
2016-01-01
Key points A classic unresolved issue in human integrative physiology involves the role of exercise intensity, duration and volume in regulating skeletal muscle adaptations to training.We employed counterweighted single‐leg cycling as a unique within‐subject model to investigate the role of exercise intensity in promoting training‐induced increases in skeletal muscle mitochondrial content.Six sessions of high‐intensity interval training performed over 2 weeks elicited greater increases in citrate synthase maximal activity and mitochondrial respiration compared to moderate‐intensity continuous training matched for total work and session duration.These data suggest that exercise intensity, and/or the pattern of contraction, is an important determinant of exercise‐induced skeletal muscle remodelling in humans. Abstract We employed counterweighted single‐leg cycling as a unique model to investigate the role of exercise intensity in human skeletal muscle remodelling. Ten young active men performed unilateral graded‐exercise tests to measure single‐leg V˙O2, peak and peak power (W peak). Each leg was randomly assigned to complete six sessions of high‐intensity interval training (HIIT) [4 × (5 min at 65% W peak and 2.5 min at 20% W peak)] or moderate‐intensity continuous training (MICT) (30 min at 50% W peak), which were performed 10 min apart on each day, in an alternating order. The work performed per session was matched for MICT (143 ± 8.4 kJ) and HIIT (144 ± 8.5 kJ, P > 0.05). Post‐training, citrate synthase (CS) maximal activity (10.2 ± 0.8 vs. 8.4 ± 0.9 mmol kg protein−1 min−1) and mass‐specific [pmol O2•(s•mg wet weight)−1] oxidative phosphorylation capacities (complex I: 23.4 ± 3.2 vs. 17.1 ± 2.8; complexes I and II: 58.2 ± 7.5 vs. 42.2 ± 5.3) were greater in HIIT relative to MICT (interaction effects, P < 0.05); however, mitochondrial function [i.e. pmol O2•(s•CS maximal activity)−1] measured under various conditions was unaffected by training (P > 0.05). In whole muscle, the protein content of COXIV (24%), NDUFA9 (11%) and mitofusin 2 (MFN2) (16%) increased similarly across groups (training effects, P < 0.05). Cytochrome c oxidase subunit IV (COXIV) and NADH:ubiquinone oxidoreductase subunit A9 (NDUFA9) were more abundant in type I than type II fibres (P < 0.05) but training did not increase the content of COXIV, NDUFA9 or MFN2 in either fibre type (P > 0.05). Single‐leg V˙O2, peak was also unaffected by training (P > 0.05). In summary, single‐leg cycling performed in an interval compared to a continuous manner elicited superior mitochondrial adaptations in human skeletal muscle despite equal total work. PMID:27396440
Cabral-Santos, C; Giacon, T R; Campos, E Z; Gerosa-Neto, J; Rodrigues, B; Vanderlei, L C M; Lira, F S
2016-06-01
The aim of this study was to compare heart rate variability (HRV) recovery after two iso-volume (5 km) exercises performed at different intensities. 14 subjects volunteered (25.17±5.08 years; 74.7±6.28 kg; 175±0.05 cm; 59.56±5.15 mL·kg(-1)·min(-1)) and after determination of peak oxygen uptake (VO2Peak) and the speed associated with VO2Peak (sVO2Peak), the subjects completed 2 random experimental trials: high-intensity exercise (HIE - 1:1 at 100% sVO2Peak), and moderate-intensity continuous exercise (MIE - 70% sVO2Peak). HRV and RR intervals were monitored before, during and after the exercise sessions together with, the HRV analysis in the frequency domains (high-frequency - HF: 0.15 to 0.4 Hz and low-frequency - LF: 0.04 to 0.15 Hz components) and the ratio between them (LF/HF). Statistical analysis comparisons between moments and between HIE and MIE were performed using a mixed model. Both exercise sessions modified LFlog, HFlog, and LF/HF (F=16.54, F=19.32 and F=5.17, p<0.05, respectively). A group effect was also found for LFlog (F=23.91, p<0.05), and HFlog (F=57.55, p< 0.05). LF/HF returned to resting value 15 min after MIE exercise and 20 min after HIE exercise. This means that the heavy domain (aerobic and anaerobic threshold) induces dissimilar autonomic modification in physically active subjects. Both HIE and MIE modify HRV, and generally HIE delays parasympathetic autonomic modulation recovery after iso-volume exercise. © Georg Thieme Verlag KG Stuttgart · New York.
In situ quantitative analysis of individual H2O-CO2 fluid inclusions by laser Raman spectroscopy
Azbej, T.; Severs, M.J.; Rusk, B.G.; Bodnar, R.J.
2007-01-01
Raman spectral parameters for the Raman ??1 (1285??cm- 1) and 2??2 (1388??cm- 1) bands for CO2 and for the O-H stretching vibration band of H2O (3600??cm- 1) were determined in H2O-CO2 fluid inclusions. Synthetic fluid inclusions containing 2.5 to 50??mol% CO2 were analyzed at temperatures equal to or greater than the homogenization temperature. The results were used to develop an empirical relationship between composition and Raman spectral parameters. The linear peak intensity ratio (IR = ICO2/(ICO2 + IH2O)) is related to the CO2 concentration in the inclusion according to the relation:Mole % C O2 = e- 3.959 IR2 + 8.0734 IRwhere ICO2 is the intensity of the 1388 cm- 1 peak and IH2O is the intensity of the 3600 cm- 1 peak. The relationship between linear peak intensity and composition was established at 350????C for compositions ranging from 2.5 to 50??mol% CO2. The CO2-H2O linear peak intensity ratio (IR) varies with temperature and the relationship between composition and IR is strictly valid only if the inclusions are analyzed at 350????C. The peak area ratio is defined as AR = ACO2/(ACO2 + AH2O), where ACO2 is the integrated area under the 1388??cm- 1 peak and AH2O is the integrated area under the 3600??cm- 1 peak. The relationship between peak area ratio (AR) and the CO2 concentration in the inclusions is given as:Mole % C O2 = 312.5 AR. The equation relating peak area ratio and composition is valid up to 25??mol% CO2 and from 300 to 450????C. The relationship between linear peak intensity ratio and composition should be used for inclusions containing ??? 50??mol% CO2 and which can be analyzed at 350????C. The relationship between composition and peak area ratios should be used when analyzing inclusions at temperatures less than or greater than 350????C (300-450) but can only be used for compositions ??? 25??mol% CO2. Note that this latter relationship has a somewhat larger standard deviation compared to the intensity ratio relationship. Calibration relationships employing peak areas for both members of the Fermi diad (??1 at 1285??cm- 1 and 2??2 at 1388??cm- 1) were slightly poorer than those using only the 2??2 (1388??cm- 1) member owing to interference from quartz peak at approximately 1160??cm- 1. The technique has been applied to natural low-salinity H2O-CO2 inclusions from the Butte, Montana, porphyry copper-molybdenum deposit. Carbon dioxide concentrations obtained range from below detection to 4.2??mol% CO2, and are in good agreement with concentrations determined previously based on microthermometric and petrographic observations. ?? 2007 Elsevier B.V. All rights reserved.
Gomes Neto, Mansueto; Durães, André Rodrigues; Conceição, Lino Sergio Rocha; Saquetto, Micheli Bernardone; Ellingsen, Øyvind; Carvalho, Vitor Oliveira
2018-06-15
The aim of this study was to investigate the effects of high intensity interval training (HIIT) versus moderate intensity continuous training (MICT) in heart failure patients with reduced ejection fraction (HFrEF). Despite the well-known positive effects of exercise in heart failure patients, the best mode of exercise is still under discussion. We searched Pubmed/MEDLINE, Cochrane Central Register of Controlled Trials, PEDro data base, and SciELO (from the earliest date available to October 2017) for randomized controlled trials that evaluated the effects of HIIT versus MICT in HFrEF patients. Weighted mean differences (WMD) with 95% confidence interval (CI) were calculated, and heterogeneity was assessed using the I 2 test. 13 studies met the study criteria, including 411 patients. Compared to MICT, HIIT resulted in improvement in Peak VO 2 WMD (1.35 mL·kg -1 ·min -1 95% CI: 0.03 to 2.64 N = 411). HIIT resulted in no difference in VE/VCO 2 slope WMD (-1.21 95% CI: -3.0 to 0.58 N = 135), and quality of life measured by Minnesota Living with Heart Failure questionnaire WMD (1.19 95% CI: -5.81 to 8.19 N = 79). Sub-group analyses comparing studies with and without isocaloric exercise training protocol also showed a nonsignificant difference in peak VO 2 for participants in the HIIT group compared with MICT group. HIIT improves peak VO 2 and should be considered as a component of care of HFrEF patients. However, its superiority versus MICT disappears when isocaloric protocols are compared. An important caveat is uncertainty and variation of actual training intensities compared to program targets. Copyright © 2018 Elsevier B.V. All rights reserved.
Kott, Matthias; Elke, Gunnar; Reinicke, Maike; Winoto-Morbach, Supandi; Schädler, Dirk; Zick, Günther; Frerichs, Inéz; Weiler, Norbert; Schütze, Stefan
2014-01-01
Acid sphingomyelinase is involved in lipid signalling pathways and regulation of apoptosis by the generation of ceramide and plays an important role during the host response to infectious stimuli. It thus has the potential to be used as a novel diagnostic marker in the management of critically ill patients. The objective of our study was to evaluate acid sphingomyelinase serum activity (ASM) as a diagnostic and prognostic marker in a mixed intensive care unit population before, during, and after systemic inflammation. 40 patients admitted to the intensive care unit at risk for developing systemic inflammation (defined as systemic inflammatory response syndrome plus a significant procalcitonin [PCT] increase) were included. ASM was analysed on ICU admission, before (PCT before), during (PCT peak) and after (PCT low) onset of SIRS. Patients undergoing elective surgery served as control (N = 8). Receiver-operating characteristics curves were computed. ASM significantly increased after surgery in the eight control patients. Patients from the intensive care unit had significantly higher ASM on admission than control patients after surgery. 19 out of 40 patients admitted to the intensive care unit developed systemic inflammation and 21 did not, with no differences in ASM between these two groups on admission. In patients with SIRS and PCT peak, ASM between admission and PCT before was not different, but further increased at PCT peak in non-survivors and was significantly higher at PCT low compared to survivors. Survivors exhibited decreased ASM at PCT peak and PCT low. Receiver operating curve analysis on discrimination of ICU mortality showed an area under the curve of 0.79 for ASM at PCT low. In summary, ASM was generally higher in patients admitted to the intensive care unit compared to patients undergoing uncomplicated surgery. ASM did not indicate onset of systemic inflammation. In contrast to PCT however, it remained high in non-surviving ICU patients after systemic inflammation.
Angadi, Siddhartha S; Mookadam, Farouk; Lee, Chong D; Tucker, Wesley J; Haykowsky, Mark J; Gaesser, Glenn A
2015-09-15
Heart failure with preserved ejection fraction (HFpEF) is a major cause of morbidity and mortality. Exercise training is an established adjuvant therapy in heart failure; however, the effects of high-intensity interval training (HIIT) in HFpEF are unknown. We compared the effects of HIIT vs. moderate-intensity aerobic continuous training (MI-ACT) on peak oxygen uptake (V̇o₂peak), left ventricular diastolic dysfunction, and endothelial function in patients with HFpEF. Nineteen patients with HFpEF (age 70 ± 8.3 yr) were randomized to either HIIT (4 × 4 min at 85-90% peak heart rate, with 3 min active recovery) or MI-ACT (30 min at 70% peak heart rate). Fifteen patients completed exercise training (HIIT: n = 9; MI-ACT: n = 6). Patients trained 3 days/wk for 4 wk. Before and after training patients underwent a treadmill test for V̇o₂peak determination, 2D-echocardiography for assessment of left ventricular diastolic dysfunction, and brachial artery flow-mediated dilation (FMD) for assessment of endothelial function. HIIT improved V̇o₂peak (pre = 19.2 ± 5.2 ml·kg(-1)·min(-1); post = 21.0 ± 5.2 ml·kg(-1)·min(-1); P = 0.04) and left ventricular diastolic dysfunction grade (pre = 2.1 ± 0.3; post = 1.3 ± 0.7; P = 0.02), but FMD was unchanged (pre = 6.9 ± 3.7%; post = 7.0 ± 4.2%). No changes were observed following MI-ACT. A trend for reduced left atrial volume index was observed following HIIT compared with MI-ACT (-3.3 ± 6.6 vs. +5.8 ± 10.7 ml/m(2); P = 0.06). In HFpEF patients 4 wk of HIIT significantly improved V̇o₂peak and left ventricular diastolic dysfunction. HIIT may provide a more robust stimulus than MI-ACT for early exercise training adaptations in HFpEF. Copyright © 2015 the American Physiological Society.
Chisholm, Jim
2005-06-01
A further comparison of the Health and Safety Executive (HSE) standard quartz, A9950 (Sikron F600), and the National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) 1878, standard respirable alpha-quartz, has been carried out for the four principal diffraction peaks. In the earlier comparison by Jeyaratnam and Nagar (1993, Ann Occup Hyg; 37: 167-79), the standards were both treated in ways which might change the particle size distribution and therefore the proportion of crystalline quartz. The two standards have now been compared in the most direct way possible with the minimum of sample treatment. There are no significant differences in the diffraction peak positions for the two standards. Nor do the peak area intensities differ significantly. The peak height intensities are consistently and significantly higher for Sikron F600 than for NIST SRM 1878. The particle size broadening of the diffraction peaks is evidently greater for NIST 1878, whose mass median diameter is quoted as 1.6 microm against 2.6 microm for Sikron F600. Taking the certified reference value for SRM 1878 as 95.5 +/- 1.1% crystalline quartz, the HSE standard A9950 (Sikron F600) contains 96.3 +/- 1.4% crystalline quartz based on a comparison of peak area intensities. On the same basis but using peak height intensities, the nominal crystalline quartz content of A9950 (Sikron F600) is 101.2 +/- 1.8%. Results obtained by comparison of quartz standards may not be generally applicable because of the effect of sample treatment on particle size and crystalline quartz content.
Peak Running Intensity of International Rugby: Implications for Training Prescription.
Delaney, Jace A; Thornton, Heidi R; Pryor, John F; Stewart, Andrew M; Dascombe, Ben J; Duthie, Grant M
2017-09-01
To quantify the duration and position-specific peak running intensities of international rugby union for the prescription and monitoring of specific training methodologies. Global positioning systems (GPS) were used to assess the activity profile of 67 elite-level rugby union players from 2 nations across 33 international matches. A moving-average approach was used to identify the peak relative distance (m/min), average acceleration/deceleration (AveAcc; m/s 2 ), and average metabolic power (P met ) for a range of durations (1-10 min). Differences between positions and durations were described using a magnitude-based network. Peak running intensity increased as the length of the moving average decreased. There were likely small to moderate increases in relative distance and AveAcc for outside backs, halfbacks, and loose forwards compared with the tight 5 group across all moving-average durations (effect size [ES] = 0.27-1.00). P met demands were at least likely greater for outside backs and halfbacks than for the tight 5 (ES = 0.86-0.99). Halfbacks demonstrated the greatest relative distance and P met outputs but were similar to outside backs and loose forwards in AveAcc demands. The current study has presented a framework to describe the peak running intensities achieved during international rugby competition by position, which are considerably higher than previously reported whole-period averages. These data provide further knowledge of the peak activity profiles of international rugby competition, and this information can be used to assist coaches and practitioners in adequately preparing athletes for the most demanding periods of play.
NASA Technical Reports Server (NTRS)
Chackerian, Charles, Jr.; Kshirsagar, R. J.; Giver, L. P.; Brown, L. R.; Condon, Estelle P. (Technical Monitor)
1999-01-01
This work was initiated to compare absolute line intensities retrieved with the Kitt Peak FTS (Fourier Transform Spectrometer) and Ames BOMEM FTS. Since thermal contaminations can be a problem using the BOMEM instrument if proper precautions are not taken it was thought that measurements done at 6300 per cm would more easily result in satisfactory intercomparisons. Very recent measurements of the CO 3 <-- 0 band fine intensities confirms results reported here that the intensities listed in HITRAN (High Resolution Molecular Absorption Database) for this band are on the order of six to seven percent too low. All of the infrared intensities in the current HITRAN tabulation are based on the electric dipole moment function reported fifteen years ago. The latter in turn was partly based on intensities for the 3 <-- 0 band reported thirty years ago. We have, therefore, redetermined the electric dipole moment function of ground electronic state CO.
Trojan, Michael; Rengier, Fabian; Kotelis, Drosos; Müller-Eschner, Matthias; Partovi, Sasan; Fink, Christian; Karmonik, Christof; Böckler, Dittmar; Kauczor, Hans-Ulrich; von Tengg-Kobligk, Hendrik
2017-01-01
To prospectively evaluate our hypothesis that three-dimensional time-resolved contrast-enhanced magnetic resonance angiography (TR-MRA) is able to detect hemodynamic alterations in patients with chronic expanding aortic dissection compared to stable aortic dissections. 20 patients with chronic or residual aortic dissection in the descending aorta and patent false lumen underwent TR-MRA of the aorta at 1.5 T and repeated follow-up imaging (mean follow-up 5.4 years). 7 patients showed chronic aortic expansion and 13 patients had stable aortic diameters. Regions of interest were placed in the nondissected ascending aorta and the false lumen of the descending aorta at the level of the diaphragm (FL-diaphragm level) resulting in respective time-intensity curves. For the FL-diaphragm level, time-to-peak intensity and full width at half maximum were significantly shorter in the expansion group compared to the stable group ( p = 0.027 and p = 0.003), and upward and downward slopes of time-intensity curves were significantly steeper ( p = 0.015 and p = 0.005). The delay of peak intensity in the FL-diaphragm level compared to the nondissected ascending aorta was significantly shorter in the expansion group compared to the stable group ( p = 0.01). 3D TR-MRA detects significant alterations of hemodynamics within the patent false lumen of chronic expanding aortic dissections compared to stable aortic dissections.
Comparative analysis of peak-detection techniques for comprehensive two-dimensional chromatography.
Latha, Indu; Reichenbach, Stephen E; Tao, Qingping
2011-09-23
Comprehensive two-dimensional gas chromatography (GC×GC) is a powerful technology for separating complex samples. The typical goal of GC×GC peak detection is to aggregate data points of analyte peaks based on their retention times and intensities. Two techniques commonly used for two-dimensional peak detection are the two-step algorithm and the watershed algorithm. A recent study [4] compared the performance of the two-step and watershed algorithms for GC×GC data with retention-time shifts in the second-column separations. In that analysis, the peak retention-time shifts were corrected while applying the two-step algorithm but the watershed algorithm was applied without shift correction. The results indicated that the watershed algorithm has a higher probability of erroneously splitting a single two-dimensional peak than the two-step approach. This paper reconsiders the analysis by comparing peak-detection performance for resolved peaks after correcting retention-time shifts for both the two-step and watershed algorithms. Simulations with wide-ranging conditions indicate that when shift correction is employed with both algorithms, the watershed algorithm detects resolved peaks with greater accuracy than the two-step method. Copyright © 2011 Elsevier B.V. All rights reserved.
Yu, Peiqiang; Damiran, Daalkhaijav; Azarfar, Arash; Niu, Zhiyuan
2011-01-01
The objective of this study was to use DRIFT spectroscopy with uni- and multivariate molecular spectral analyses as a novel approach to detect molecular features of spectra mainly associated with carbohydrate in the co-products (wheat DDGS, corn DDGS, blend DDGS) from bioethanol processing in comparison with original feedstock (wheat (Triticum), corn (Zea mays)). The carbohydrates related molecular spectral bands included: A_Cell (structural carbohydrates, peaks area region and baseline: ca. 1485-1188 cm(-1)), A_1240 (structural carbohydrates, peak area centered at ca. 1240 cm(-1) with region and baseline: ca. 1292-1198 cm(-1)), A_CHO (total carbohydrates, peaks region and baseline: ca. 1187-950 cm(-1)), A_928 (non-structural carbohydrates, peak area centered at ca. 928 cm(-1) with region and baseline: ca. 952-910 cm(-1)), A_860 (non-structural carbohydrates, peak area centered at ca. 860 cm(-1) with region and baseline: ca. 880-827 cm(-1)), H_1415 (structural carbohydrate, peak height centered at ca. 1415 cm(-1) with baseline: ca. 1485-1188 cm(-1)), H_1370 (structural carbohydrate, peak height at ca. 1370 cm(-1) with a baseline: ca. 1485-1188 cm(-1)). The study shows that the grains had lower spectral intensity (KM Unit) of the cellulosic compounds of A_1240 (8.5 vs. 36.6, P < 0.05), higher (P < 0.05) intensities of the non-structural carbohydrate of A_928 (17.3 vs. 2.0) and A_860 (20.7 vs. 7.6) than their co-products from bioethanol processing. There were no differences (P > 0.05) in the peak area intensities of A_Cell (structural CHO) at 1292-1198 cm(-1) and A_CHO (total CHO) at 1187-950 cm(-1) with average molecular infrared intensity KM unit of 226.8 and 508.1, respectively. There were no differences (P > 0.05) in the peak height intensities of H_1415 and H_1370 (structural CHOs) with average intensities 1.35 and 1.15, respectively. The multivariate molecular spectral analyses were able to discriminate and classify between the corn and corn DDGS molecular spectra, but not wheat and wheat DDGS. This study indicated that the bioethanol processing changes carbohydrate molecular structural profiles, compared with the original grains. However, the sensitivities of different types of carbohydrates and different grains (corn and wheat) to the processing differ. In general, the bioethanol processing increases the molecular spectral intensities for the structural carbohydrates and decreases the intensities for the non-structural carbohydrates. Further study is needed to quantify carbohydrate related molecular spectral features of the bioethanol co-products in relation to nutrient supply and availability of carbohydrates.
Hansen, D; Dendale, P; Jonkers, R A M; Beelen, M; Manders, R J F; Corluy, L; Mullens, A; Berger, J; Meeusen, R; van Loon, L J C
2009-09-01
Exercise represents an effective interventional strategy to improve glycaemic control in type 2 diabetes patients. However, the impact of exercise intensity on the benefits of exercise training remains to be established. In the present study, we compared the clinical benefits of 6 months of continuous low- to moderate-intensity exercise training with those of continuous moderate- to high-intensity exercise training, matched for energy expenditure, in obese type 2 diabetes patients. Fifty male obese type 2 diabetes patients (age 59 +/- 8 years, BMI 32 +/- 4 kg/m(2)) participated in a 6 month continuous endurance-type exercise training programme. All participants performed three supervised exercise sessions per week, either 55 min at 50% of whole body peak oxygen uptake (VO(2)peak (low to moderate intensity) or 40 min at 75% of VO(2)peak (moderate to high intensity). Oral glucose tolerance, blood glycated haemoglobin, lipid profile, body composition, maximal workload capacity, whole body and skeletal muscle oxidative capacity and skeletal muscle fibre type composition were assessed before and after 2 and 6 months of intervention. The entire 6 month intervention programme was completed by 37 participants. Continuous endurance-type exercise training reduced blood glycated haemoglobin levels, LDL-cholesterol concentrations, body weight and leg fat mass, and increased VO(2)peak, lean muscle mass and skeletal muscle cytochrome c oxidase and citrate synthase activity (p < 0.05). No differences were observed between the groups training at low to moderate or moderate to high intensity. When matched for energy cost, prolonged continuous low- to moderate-intensity endurance-type exercise training is equally effective as continuous moderate- to high-intensity training in lowering blood glycated haemoglobin and increasing whole body and skeletal muscle oxidative capacity in obese type 2 diabetes patients. ISRCTN32206301 None.
Fan, Tingbo; Liu, Zhenbo; Zhang, Dong; Tang, Mengxing
2013-03-01
Lesion formation and temperature distribution induced by high-intensity focused ultrasound (HIFU) were investigated both numerically and experimentally via two energy-delivering strategies, i.e., sequential discrete and continuous scanning modes. Simulations were presented based on the combination of Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation and bioheat equation. Measurements were performed on tissue-mimicking phantoms sonicated by a 1.12-MHz single-element focused transducer working at an acoustic power of 75 W. Both the simulated and experimental results show that, in the sequential discrete mode, obvious saw-tooth-like contours could be observed for the peak temperature distribution and the lesion boundaries, with the increasing interval space between two adjacent exposure points. In the continuous scanning mode, more uniform peak temperature distributions and lesion boundaries would be produced, and the peak temperature values would decrease significantly with the increasing scanning speed. In addition, compared to the sequential discrete mode, the continuous scanning mode could achieve higher treatment efficiency (lesion area generated per second) with a lower peak temperature. The present studies suggest that the peak temperature and tissue lesion resulting from the HIFU exposure could be controlled by adjusting the transducer scanning speed, which is important for improving the HIFU treatment efficiency.
Cuetos, María José; Gómez, Xiomar; Otero, Marta; Morán, Antonio
2010-07-01
In this paper, Fourier Transform infrared spectroscopy (FTIR) along with thermogravimetric analysis together with mass spectrometry (TG-MS analysis) were employed to study the organic matter transformation attained under anaerobic digestion of slaughterhouse waste and to establish the stability of the digestates obtained when compared with fresh wastes. Digestate samples studied were obtained from successful digestion and failed systems treating slaughterhouse waste and the organic fraction of municipal solid wastes. The FTIR spectra and TG profiles from well stabilized products (from successful digestion systems) showed an increase in the aromaticity degree and the reduction of volatile content and aliphatic structures as stabilization proceeded. On the other hand, the FTIR spectra of non-stable reactors showed a high aliphaticity degree and fat content. When comparing differential thermogravimetry (DTG) profiles of the feed and digestate samples obtained from all successful anaerobic systems, a reduction in the intensity of the low-temperature range (approximately 300 degrees C) peak was observed, while the weight loss experienced at high-temperature (450-550 degrees C) was variable for the different systems. Compared to the original waste, the intensity of the weight loss peak in the high-temperature range decreased in the reactors with higher hydraulic retention time (HRT) whereas its intensity increased and the peak was displaced to higher temperatures for the digesters with lower HRT.
Xie, Bin; Yan, Xianfeng
2017-01-01
Purpose. The aim of this study was to compare the effects of high-intensity interval training (INTERVAL) and moderate-intensity continuous training (CONTINUOUS) on aerobic capacity in cardiac patients. Methods. A meta-analysis identified by searching the PubMed, Cochrane Library, EMBASE, and Web of Science databases from inception through December 2016 compared the effects of INTERVAL and CONTINUOUS among cardiac patients. Results. Twenty-one studies involving 736 participants with cardiac diseases were included. Compared with CONTINUOUS, INTERVAL was associated with greater improvement in peak VO2 (mean difference 1.76 mL/kg/min, 95% confidence interval 1.06 to 2.46 mL/kg/min, p < 0.001) and VO2 at AT (mean difference 0.90 mL/kg/min, 95% confidence interval 0.0 to 1.72 mL/kg/min, p = 0.03). No significant difference between the INTERVAL and CONTINUOUS groups was observed in terms of peak heart rate, peak minute ventilation, VE/VCO2 slope and respiratory exchange ratio, body mass, systolic or diastolic blood pressure, triglyceride or low- or high-density lipoprotein cholesterol level, flow-mediated dilation, or left ventricular ejection fraction. Conclusions. This study showed that INTERVAL improves aerobic capacity more effectively than does CONTINUOUS in cardiac patients. Further studies with larger samples are needed to confirm our observations. PMID:28386556
Average Emissivity Curve of Batse Gamma-Ray Bursts with Different Intensities
NASA Technical Reports Server (NTRS)
Mitrofanov, Igor G.; Litvak, Maxim L.; Briggs, Michael S.; Paciesas, William S.; Pendleton, Geoffrey N.; Preece, Robert D.; Meegan, Charles A.
1999-01-01
Six intensity groups with approximately 150 BATSE gamma-ray bursts each are compared using average emissivity curves. Time stretch factors for each of the dimmer groups are estimated with respect to the brightest group, which serves as the reference, taking into account the systematics of counts-produced noise effects and choice statistics. A stretching/intensity anticorrelation is found with good statistical significance during the average back slopes of bursts. A stretch factor approximately 2 is found between the 150 dimmest bursts, with peak flux less than 0.45 photons/sq cm.s, and the 147 brightest bursts, with peak flux greater than 4.1 photons/sq cm.s. On the other hand, while a trend of increasing stretching factor may exist for rise fronts for bursts with decreasing peak flux from greater than 4.1 photons/sq cm.s down to 0.7 photons/sq cm.s, the magnitude of the stretching factor is less than approximately 1.4 and is therefore inconsistent with stretching factor of back slope.
Allen, Nicholas G; Higham, Samuel M; Mendham, Amy E; Kastelein, Tegan E; Larsen, Penelope S; Duffield, Rob
2017-06-01
This study examined the effects of high-intensity interval training (HIIT; 30 s sprint, 4-5 min passive recovery) and prolonged intermittent sprint training (PIST; 10 s sprint, 2-3 min moderate exercise) on the systemic inflammatory markers C-reactive protein (CRP) and tumor necrosis factor-α (TNF-α), aerobic capacity, and anthropometry in a middle-aged, sedentary population. Fifty-five sedentary adults (age 49.2 ± 6.1 years) were randomised into HIIT (n = 20), PIST (n = 21), or a sedentary control group (CTRL n = 14). HIIT and PIST performed three training sessions per week for 9 weeks on a cycle ergometer, matched for total high-intensity time, while CTRL continued normal sedentary behaviours. Pre- and post-intervention testing involved measures of anthropometry, peak oxygen consumption (VO 2peak ), and venous blood collection for analyses of CRP and TNF-α. HIIT and PIST increased VO 2peak compared to CTRL (+3.66 ± 2.23 and 3.74 ± 2.62 mL kg min -1 ). A group × time interaction (p = 0.042) and main effect of time (p = 0.026) were evident for waist girth, with only HIIT showing a significant reduction compared to CTRL (-2.1 ± 2.8 cm). TNF-α and CRP showed no group × time interaction or time effect (p > 0.05). In sedentary individuals, 9 weeks of HIIT or PIST were effective to improve aerobic capacity; however, only HIIT significantly reduced waist girth and WHR compared to CTRL. Markers of systemic inflammation remained unchanged across all groups. Accordingly, for inflammation and VO2 peak , the distribution of sprints and the active or passive recovery periods are inconsequential provided that total duration of high-intensity efforts is similar.
Devin, James L; Sax, Andrew T; Hughes, Gareth I; Jenkins, David G; Aitken, Joanne F; Chambers, Suzanne K; Dunn, Jeffrey C; Bolam, Kate A; Skinner, Tina L
2016-06-01
Following colorectal cancer diagnosis and anti-cancer therapy, declines in cardiorespiratory fitness and body composition lead to significant increases in morbidity and mortality. There is increasing interest within the field of exercise oncology surrounding potential strategies to remediate these adverse outcomes. This study compared 4 weeks of moderate-intensity exercise (MIE) and high-intensity exercise (HIE) training on peak oxygen consumption (V̇O2peak) and body composition in colorectal cancer survivors. Forty seven post-treatment colorectal cancer survivors (HIE = 27 months post-treatment; MIE = 38 months post-treatment) were randomised to either HIE [85-95 % peak heart rate (HRpeak)] or MIE (70 % HRpeak) in equivalence with current physical activity guidelines and completed 12 training sessions over 4 weeks. HIE was superior to MIE in improving absolute (p = 0.016) and relative (p = 0.021) V̇O2peak. Absolute (+0.28 L.min(-1), p < 0.001) and relative (+3.5 ml.kg(-1).min(-1), p < 0.001) V̇O2 peak were increased in the HIE group but not the MIE group following training. HIE led to significant increases in lean mass (+0.72 kg, p = 0.002) and decreases in fat mass (-0.74 kg, p < 0.001) and fat percentage (-1.0 %, p < 0.001), whereas no changes were observed for the MIE group. There were no severe adverse events. In response to short-term training, HIE is a safe, feasible and efficacious intervention that offers clinically meaningful improvements in cardiorespiratory fitness and body composition for colorectal cancer survivors. HIE appears to offer superior improvements in cardiorespiratory fitness and body composition in comparison to current physical activity recommendations for colorectal cancer survivors and therefore may be an effective clinical utility following treatment.
NASA Astrophysics Data System (ADS)
Tan, Bingyao; Mason, Erik; MacLellan, Ben; Bizheva, Kostadinka
2017-02-01
Visually evoked changes of retinal blood flow can serve as an important research tool to investigate eye disease such as glaucoma and diabetic retinopathy. In this study we used a combined, research-grade, high-resolution Doppler OCT+ERG system to study changes in the retinal blood flow (RBF) and retinal neuronal activity in response to visual stimuli of different intensities, durations and type (flicker vs single flash). Specifically, we used white light stimuli of 10 ms and 200 ms single flash, 1s and 2s for flickers stimuli of 20% duty cycle. The study was conducted in-vivo in pigmented rats. Both single flash (SF) and flicker stimuli caused increase in the RBF. The 10 ms SF stimulus did not generate any consistent measurable response, while the 200 ms SF of the same intensity generated 4% change in the RBF peaking at 1.5 s after the stimulus onset. Single flash stimuli introduced 2x smaller change in RBF and 30% earlier RBF peak response compared to flicker stimuli of the same intensity and duration. Doubling the intensity of SF or flicker stimuli increased the RBF peak magnitude by 1.5x. Shortening the flicker stimulus duration by 2x increased the RBF recovery rate by 2x, however, had no effect on the rate of RBF change from baseline to peak.
Automated peak picking and peak integration in macromolecular NMR spectra using AUTOPSY.
Koradi, R; Billeter, M; Engeli, M; Güntert, P; Wüthrich, K
1998-12-01
A new approach for automated peak picking of multidimensional protein NMR spectra with strong overlap is introduced, which makes use of the program AUTOPSY (automated peak picking for NMR spectroscopy). The main elements of this program are a novel function for local noise level calculation, the use of symmetry considerations, and the use of lineshapes extracted from well-separated peaks for resolving groups of strongly overlapping peaks. The algorithm generates peak lists with precise chemical shift and integral intensities, and a reliability measure for the recognition of each peak. The results of automated peak picking of NOESY spectra with AUTOPSY were tested in combination with the combined automated NOESY cross peak assignment and structure calculation routine NOAH implemented in the program DYANA. The quality of the resulting structures was found to be comparable with those from corresponding data obtained with manual peak picking. Copyright 1998 Academic Press.
NASA Technical Reports Server (NTRS)
Idone, V. P.; Orville, R. E.
1985-01-01
The correlation between peak relative light intensity L(R) and stroke peak current I(R) is examined for 39 subsequent return strokes in two triggered lightning flashes. One flash contained 19 strokes and the other 20 strokes for which direct measurements were available of the return stroke peak current at ground. Peak currents ranged from 1.6 to 21 kA. The measurements of peak relative light intensity were obtained from photographic streak recordings using calibrated film and microsecond resolution. Correlations, significant at better than the 0.1 percent level, were found for several functional relationships. Although a relation between L(R) and I(R) is evident in these data, none of the analytical relations considered is clearly favored. The correlation between L(R) and the maximum rate of current rise is also examined, but less correlation than between L(R) and I(R) is found. In addition, the peak relative intensity near ground is evaluated for 22 dart leaders, and a mean ratio of peak dart leader to peak return stroke relative light intensity was found to be 0.1 with a range of 0.02-0.23. Using two different methods, the peak current near ground in these dart leaders is estimated to range from 0.1 to 6 kA.
Effect of pressure on the α relaxation in glycerol and xylitol
NASA Astrophysics Data System (ADS)
Paluch, M.; Casalini, R.; Hensel-Bielowka, S.; Roland, C. M.
2002-06-01
The effect of pressure on the dielectric relaxation of two polyhydroxy alcohols is examined by analysis of existing data on glycerol, together with new measurements on xylitol. The fragility, or Tg-normalized temperature dependence, changes with pressure for low pressures, but becomes invariant above 1 GPa. When compared at temperatures for which the α-relaxation times are equal, there is no effect of pressure (<1 GPa) on the shape of the α dispersion at higher temperatures. However, nearer Tg, pressure broadens the α peak, consistent with the expected correlation of fragility with the breadth of the relaxation function. We also observe that the α-relaxation peaks for both glycerol and xylitol show an excess intensity at higher frequencies. For xylitol, unlike for glycerol, at lower temperatures this wing disjoins to form a separate peak. For both glass formers, elevated pressure causes the excess wing to become more separated from the peak maximum; that is, the properties of the primary and excess intensities are not correlated. This implies that the excess wing in glycerol is also a distinct secondary process, although it cannot be resolved from the primary peak.
Exact extraction method for road rutting laser lines
NASA Astrophysics Data System (ADS)
Hong, Zhiming
2018-02-01
This paper analyzes the importance of asphalt pavement rutting detection in pavement maintenance and pavement administration in today's society, the shortcomings of the existing rutting detection methods are presented and a new rutting line-laser extraction method based on peak intensity characteristic and peak continuity is proposed. The intensity of peak characteristic is enhanced by a designed transverse mean filter, and an intensity map of peak characteristic based on peak intensity calculation for the whole road image is obtained to determine the seed point of the rutting laser line. Regarding the seed point as the starting point, the light-points of a rutting line-laser are extracted based on the features of peak continuity, which providing exact basic data for subsequent calculation of pavement rutting depths.
Trojan, Michael; Kotelis, Drosos; Müller-Eschner, Matthias; Partovi, Sasan; Fink, Christian; Karmonik, Christof; Böckler, Dittmar; Kauczor, Hans-Ulrich; von Tengg-Kobligk, Hendrik
2017-01-01
Objective To prospectively evaluate our hypothesis that three-dimensional time-resolved contrast-enhanced magnetic resonance angiography (TR-MRA) is able to detect hemodynamic alterations in patients with chronic expanding aortic dissection compared to stable aortic dissections. Materials and Methods 20 patients with chronic or residual aortic dissection in the descending aorta and patent false lumen underwent TR-MRA of the aorta at 1.5 T and repeated follow-up imaging (mean follow-up 5.4 years). 7 patients showed chronic aortic expansion and 13 patients had stable aortic diameters. Regions of interest were placed in the nondissected ascending aorta and the false lumen of the descending aorta at the level of the diaphragm (FL-diaphragm level) resulting in respective time-intensity curves. Results For the FL-diaphragm level, time-to-peak intensity and full width at half maximum were significantly shorter in the expansion group compared to the stable group (p = 0.027 and p = 0.003), and upward and downward slopes of time-intensity curves were significantly steeper (p = 0.015 and p = 0.005). The delay of peak intensity in the FL-diaphragm level compared to the nondissected ascending aorta was significantly shorter in the expansion group compared to the stable group (p = 0.01). Conclusions 3D TR-MRA detects significant alterations of hemodynamics within the patent false lumen of chronic expanding aortic dissections compared to stable aortic dissections. PMID:29317855
Yu, Peiqiang; Damiran, Daalkhaijav; Azarfar, Arash; Niu, Zhiyuan
2011-01-01
The objective of this study was to use DRIFT spectroscopy with uni- and multivariate molecular spectral analyses as a novel approach to detect molecular features of spectra mainly associated with carbohydrate in the co-products (wheat DDGS, corn DDGS, blend DDGS) from bioethanol processing in comparison with original feedstock (wheat (Triticum), corn (Zea mays)). The carbohydrates related molecular spectral bands included: A_Cell (structural carbohydrates, peaks area region and baseline: ca. 1485–1188 cm−1), A_1240 (structural carbohydrates, peak area centered at ca. 1240 cm−1 with region and baseline: ca. 1292–1198 cm−1), A_CHO (total carbohydrates, peaks region and baseline: ca. 1187–950 cm−1), A_928 (non-structural carbohydrates, peak area centered at ca. 928 cm−1 with region and baseline: ca. 952–910 cm−1), A_860 (non-structural carbohydrates, peak area centered at ca. 860 cm−1 with region and baseline: ca. 880–827 cm−1), H_1415 (structural carbohydrate, peak height centered at ca. 1415 cm−1 with baseline: ca. 1485–1188 cm−1), H_1370 (structural carbohydrate, peak height at ca. 1370 cm−1 with a baseline: ca. 1485–1188 cm−1). The study shows that the grains had lower spectral intensity (KM Unit) of the cellulosic compounds of A_1240 (8.5 vs. 36.6, P < 0.05), higher (P < 0.05) intensities of the non-structural carbohydrate of A_928 (17.3 vs. 2.0) and A_860 (20.7 vs. 7.6) than their co-products from bioethanol processing. There were no differences (P > 0.05) in the peak area intensities of A_Cell (structural CHO) at 1292–1198 cm−1 and A_CHO (total CHO) at 1187–950 cm−1 with average molecular infrared intensity KM unit of 226.8 and 508.1, respectively. There were no differences (P > 0.05) in the peak height intensities of H_1415 and H_1370 (structural CHOs) with average intensities 1.35 and 1.15, respectively. The multivariate molecular spectral analyses were able to discriminate and classify between the corn and corn DDGS molecular spectra, but not wheat and wheat DDGS. This study indicated that the bioethanol processing changes carbohydrate molecular structural profiles, compared with the original grains. However, the sensitivities of different types of carbohydrates and different grains (corn and wheat) to the processing differ. In general, the bioethanol processing increases the molecular spectral intensities for the structural carbohydrates and decreases the intensities for the non-structural carbohydrates. Further study is needed to quantify carbohydrate related molecular spectral features of the bioethanol co-products in relation to nutrient supply and availability of carbohydrates. PMID:21673931
O2 uptake kinetics during exercise at peak O2 uptake.
Scheuermann, Barry W; Barstow, Thomas J
2003-11-01
Compared with moderate- and heavy-intensity exercise, the adjustment of O2 uptake (VO2) to exercise intensities that elicit peak VO2 has received relatively little attention. This study examined the VO2 response of 21 young, healthy subjects (25 +/- 6 yr; mean +/- SD) during cycle ergometer exercise to step transitions in work rate (WR) corresponding to 90, 100, and 110% of the peak WR achieved during a preliminary ramp protocol (15-30 W/min). Gas exchange was measured breath by breath and interpolated to 1-s values. VO2 kinetics were determined by use of a two- or three-component exponential model to isolate the time constant (tau2) as representative of VO2 kinetics and the amplitude (Amp) of the primary fast component independent of the appearance of any VO2 slow component. No difference in VO2 kinetics was observed between WRs (tau90 = 24.7 +/- 9.0; tau100 = 22.8 +/- 6.7; tau110 = 21.5 +/- 9.2 s, where subscripts denote percent of peak WR; P > 0.05); nor in a subgroup of eight subjects was tau2 different from the value for moderate-intensity (
Kenny, G P; Reardon, F D; Marion, A; Thoden, J S
1995-01-01
The purpose of this study was to evaluate the relationships between heart rate (fc), oxygen consumption (VO2), peak force and average force developed at the crank in response to submaximal exercise employing a racing bicycle which was attached to an ergometer (RE), ridden on a treadmill (TC) and ridden on a 400-m track (FC). Eight male trained competitive cyclists rode at three pre-determined work intensities set at a proportion of their maximal oxygen consumption (VO2max): (1) below lactate threshold [work load that produces a VO2 which is 10% less than the lactate threshold VO2 (sub-LT)], (2) lactate threshold VO2 (LT), and (3) above lactate threshold [workload that produces a VO2 which is 10% greater than lactate threshold VO2 (supra-LT)], and equated across exercise modes on the basis of fc. Voltage signals from the crank arm were recorded as FM signals for subsequent representation of peak and average force. Open circuit VO2 measurements were done in the field by Douglas bag gas collection and in the laboratory by automated gas collection and analysis. fc was recorded with a telemeter (Polar Electro Sport Tester, PE3000). Significant differences (P < 0.05) were observed: (1) in VO2 between FC and both laboratory conditions at sub-LT intensity and LT intensities, (2) in peak force between FC and TC at sub-LT intensity, (3) in average force between FC and RE at sub-LT. No significant differences were demonstrated at supra-LT intensity for VO2. Similarly no significant differences were observed in peak and average force for either LT or supra-LT intensities. These data indicate that equating work intensities on the basis of fc measured in laboratory conditions would overestimate the VO2 which would be generated in the field and conversely, that using fc measured in the laboratory to establish field work intensity would underestimate mechanical workload experienced in the field.
Chatterji, T; Jalarvo, N; Kumar, C M N; Xiao, Y; Brückel, Th
2013-07-17
We have investigated low energy nuclear spin excitations in the strongly correlated electron compound HoCrO3. We observe clear inelastic peaks at E = 22.18 ± 0.04 μeV in both energy loss and gain sides. The energy of the inelastic peaks remains constant in the temperature range 1.5-40 K at which they are observed. The intensity of the inelastic peak increases at first with increasing temperature and then decreases at higher temperatures. The temperature dependence of the energy and intensity of the inelastic peaks is very unusual compared to that observed in other Nd, Co, V and also simple Ho compounds. Huge quasielastic scattering appears at higher temperatures presumably due to the fluctuating electronic moments of the Ho ions that get increasingly disordered at higher temperatures. The strong quasielastic scattering may also originate in the first Ho crystal-field excitations at about 1.5 meV.
Leech, Kristan A.; Kinnaird, Catherine R.; Holleran, Carey L.; Kahn, Jennifer
2016-01-01
Background High-intensity stepping practice may be a critical component to improve gait following motor incomplete spinal cord injury (iSCI). However, such practice is discouraged by traditional theories of rehabilitation that suggest high-intensity locomotor exercise degrades gait performance. Accordingly, such training is thought to reinforce abnormal movement patterns, although evidence to support this notion is limited. Objective The purposes of this study were: (1) to evaluate the effects of short-term manipulations in locomotor intensity on gait performance in people with iSCI and (2) to evaluate potential detrimental effects of high-intensity locomotor training on walking performance. Design A single-day, repeated-measures, pretraining-posttraining study design was used. Methods Nineteen individuals with chronic iSCI performed a graded-intensity locomotor exercise task with simultaneous collection of lower extremity kinematic and electromyographic data. Measures of interest were compared across intensity levels of 33%, 67%, and 100% of peak gait speed. A subset of 9 individuals participated in 12 weeks of high-intensity locomotor training. Similar measurements were collected and compared between pretraining and posttraining evaluations. Results The results indicate that short-term increases in intensity led to significant improvements in muscle activity, spatiotemporal metrics, and joint excursions, with selected improvements in measures of locomotor coordination. High-intensity locomotor training led to significant increases in peak gait speed (0.64–0.80 m/s), and spatiotemporal and kinematic metrics indicate a trend for improved coordination. Limitations Measures of gait performance were assessed during treadmill ambulation and not compared with a control group. Generalizability of these results to overground ambulation is unknown. Conclusions High-intensity locomotor exercise and training does not degrade, but rather improves, locomotor function and quality in individuals with iSCI, which contrasts with traditional theories of motor dysfunction following neurologic injury. PMID:27313241
Bilateral pedaling asymmetry during a simulated 40-km cycling time-trial.
Carpes, F P; Rossato, M; Faria, I E; Bolli Mota, C
2007-03-01
This study investigated the pedaling asymmetry during a 40-km cycling time-trial (TT). Six sub-elite competitive male cyclists pedaled a SRM Training Systems cycle ergometer throughout a simulated 40-km TT. A SRM scientific crank dynamometer was used to measure the bilateral crank torque (N.m) and pedaling cadence (rpm). All data were analyzed into 4 stages with equal length obtained according to total time. Comparisons between each stage of the 40-km TT were made by an analysis of variance (ANOVA). Dominant (DO) and non-dominant (ND) crank peak torque asymmetry was determined by the equation: asymmetry index (AI%)=[(DO-ND)/DO] 100. Pearson correlation analysis was performed to verify the relationship between exercise intensity, mean and crank peak torque. The crank peak torque was significantly (P<0.05) greater in the 4th stage compared with other stages. During the stages 2 and 3, was observed the AI% of 13.51% and 17.28%, respectively. Exercise intensity (%VO(2max)) was greater for stage 4 (P<0.05) and was highly correlated with mean and crank peak torque (r=0.97 and r=0.92, respectively) for each stage. The DO limb was always responsible for the larger crank peak torque. It was concluded that pedaling asymmetry is present during a simulated 40-km TT and an increase on crank torque output and exercise intensity elicits a reduction in pedaling asymmetry.
Kampshoff, Caroline S; Chinapaw, Mai J M; Brug, Johannes; Twisk, Jos W R; Schep, Goof; Nijziel, Marten R; van Mechelen, Willem; Buffart, Laurien M
2015-10-29
International evidence-based guidelines recommend physical exercise to form part of standard care for all cancer survivors. However, at present, the optimum exercise intensity is unclear. Therefore, we aimed to evaluate the effectiveness of a high intensity (HI) and low-to-moderate intensity (LMI) resistance and endurance exercise program compared with a wait list control (WLC) group on physical fitness and fatigue in a mixed group of cancer survivors who completed primary cancer treatment, including chemotherapy. Overall, 277 cancer survivors were randomized to 12 weeks of HI exercise (n = 91), LMI exercise (n = 95), or WLC (n = 91). Both interventions were identical with respect to exercise type, duration and frequency, and only differed in intensity. Measurements were performed at baseline (4-6 weeks after primary treatment) and post-intervention. The primary outcomes were cardiorespiratory fitness (peakVO2), muscle strength (grip strength and 30-second chair-stand test), and self-reported fatigue (Multidimensional Fatigue Inventory; MFI). Secondary outcomes included health-related quality of life, physical activity, daily functioning, body composition, mood, and sleep disturbances. Multilevel linear regression analyses were performed to estimate intervention effects using an intention-to-treat principle. In the HI and LMI groups, 74 % and 70 % of the participants attended more than 80 % of the prescribed exercise sessions, respectively (P = 0.53). HI (β = 2.2; 95 % CI, 1.2-3.1) and LMI (β = 1.3; 95 % CI, 0.3-2.3) exercise showed significantly larger improvements in peakVO2 compared to WLC. Improvements in peakVO2 were larger for HI than LMI exercise (β = 0.9; 95 % CI, -0.1 to 1.9), but the difference was not statistically significant (P = 0.08). No intervention effects were found for grip strength and the 30-second chair-stand test. HI and LMI exercise significantly reduced general and physical fatigue and reduced activity (MFI subscales) compared to WLC, with no significant differences between both interventions. Finally, compared to WLC, we found benefits in global quality of life and anxiety after HI exercise, improved physical functioning after HI and LMI exercise, and less problems at work after LMI exercise. Shortly after completion of cancer treatment, both HI and LMI exercise were safe and effective. There may be a dose-response relationship between exercise intensity and peakVO2, favoring HI exercise. HI and LMI exercise were equally effective in reducing general and physical fatigue. This study was registered at the Netherlands Trial Register [ NTR2153 ] on the 5th of January 2010.
Winn, Nathan C; Liu, Ying; Rector, R Scott; Parks, Elizabeth J; Ibdah, Jamal A; Kanaley, Jill A
2018-01-01
Exercise training is commonly prescribed for individuals diagnosed with nonalcoholic fatty liver disease (NAFLD); however, consensus regarding the volume and intensity of exercise for optimal benefits is lacking. Thus, we determined whether high intensity interval exercise training (HIIT) produced greater reductions in intrahepatic lipid (IHL) content and NAFLD risk factors compared with energy-matched moderate intensity continuous exercise training (MICT) in obese adults with liver steatosis. Eighteen obese adults were randomized to either 4weeks of HIIT (4min 80% VO 2 peak/3min, 50% VO 2 peak) or MICT (55% VO 2 peak, ~60min), matched for energy expenditure (~400kcal/session) and compared to five non-exercising age-matched control subjects. IHL was measured by 1 H-MRS and frequent blood samples were analyzed for glucose, insulin, c-peptide, and NEFA levels during a liquid meal test (180min) to characterize metabolic phenotype. Baseline body weight, visceral abdominal adiposity, and fasting insulin concentrations were greater in the MICT vs HIIT group (P<0.05), while IHL was tightly matched between MICT and HIIT subjects (P>0.05), albeit higher than control subjects (P<0.01). Visceral abdominal adiposity, body mass, liver aminotransferases (ALT, AST), and hepatic apoptotic/inflammatory markers (cytokeratin 18 and fetuin a) were not reduced with either exercise training intervention (P>0.05). Both HIIT and MICT lowered IHL (HIIT, -37.0±12.4%; MICT, -20.1±6.6%, P<0.05); however, the reduction in IHL was not statistically different between exercise intensities (P=0.25). Furthermore, exercise training decreased postprandial insulin, c-peptide, and lipid peroxidation levels (iAUC, P<0.05). Collectively, these findings indicate that energy-matched high intensity and moderate intensity exercise are effective at decreasing IHL and NAFLD risk that is not contingent upon reductions in abdominal adiposity or body mass. Copyright © 2017 Elsevier Inc. All rights reserved.
High-intensity interval training: Modulating interval duration in overweight/obese men.
Smith-Ryan, Abbie E; Melvin, Malia N; Wingfield, Hailee L
2015-05-01
High-intensity interval training (HIIT) is a time-efficient strategy shown to induce various cardiovascular and metabolic adaptations. Little is known about the optimal tolerable combination of intensity and volume necessary for adaptations, especially in clinical populations. In a randomized controlled pilot design, we evaluated the effects of two types of interval training protocols, varying in intensity and interval duration, on clinical outcomes in overweight/obese men. Twenty-five men [body mass index (BMI) > 25 kg · m(2)] completed baseline body composition measures: fat mass (FM), lean mass (LM) and percent body fat (%BF) and fasting blood glucose, lipids and insulin (IN). A graded exercise cycling test was completed for peak oxygen consumption (VO2peak) and power output (PO). Participants were randomly assigned to high-intensity short interval (1MIN-HIIT), high-intensity interval (2MIN-HIIT) or control groups. 1MIN-HIIT and 2MIN-HIIT completed 3 weeks of cycling interval training, 3 days/week, consisting of either 10 × 1 min bouts at 90% PO with 1 min rests (1MIN-HIIT) or 5 × 2 min bouts with 1 min rests at undulating intensities (80%-100%) (2MIN-HIIT). There were no significant training effects on FM (Δ1.06 ± 1.25 kg) or %BF (Δ1.13% ± 1.88%), compared to CON. Increases in LM were not significant but increased by 1.7 kg and 2.1 kg for 1MIN and 2MIN-HIIT groups, respectively. Increases in VO2peak were also not significant for 1MIN (3.4 ml·kg(-1) · min(-1)) or 2MIN groups (2.7 ml · kg(-1) · min(-1)). IN sensitivity (HOMA-IR) improved for both training groups (Δ-2.78 ± 3.48 units; p < 0.05) compared to CON. HIIT may be an effective short-term strategy to improve cardiorespiratory fitness and IN sensitivity in overweight males.
High-intensity interval training: Modulating interval duration in overweight/obese men
Smith-Ryan, Abbie E.; Melvin, Malia N.; Wingfield, Hailee L.
2015-01-01
Introduction High-intensity interval training (HIIT) is a time-efficient strategy shown to induce various cardiovascular and metabolic adaptations. Little is known about the optimal tolerable combination of intensity and volume necessary for adaptations, especially in clinical populations. Objectives In a randomized controlled pilot design, we evaluated the effects of two types of interval training protocols, varying in intensity and interval duration, on clinical outcomes in overweight/obese men. Methods Twenty-five men [body mass index (BMI) > 25 kg·m2] completed baseline body composition measures: fat mass (FM), lean mass (LM) and percent body fat (%BF) and fasting blood glucose, lipids and insulin (IN). A graded exercise cycling test was completed for peak oxygen consumption (VO2peak) and power output (PO). Participants were randomly assigned to high-intensity short interval (1MIN-HIIT), high-intensity interval (2MIN-HIIT) or control groups. 1MIN-HIIT and 2MIN-HIIT completed 3 weeks of cycling interval training, 3 days/week, consisting of either 10 × 1 min bouts at 90% PO with 1 min rests (1MIN-HIIT) or 5 × 2 min bouts with 1 min rests at undulating intensities (80%–100%) (2MIN-HIIT). Results There were no significant training effects on FM (Δ1.06 ± 1.25 kg) or %BF (Δ1.13% ± 1.88%), compared to CON. Increases in LM were not significant but increased by 1.7 kg and 2.1 kg for 1MIN and 2MIN-HIIT groups, respectively. Increases in VO2peak were also not significant for 1MIN (3.4 ml·kg−1·min−1) or 2MIN groups (2.7 ml·kg−1·min−1). IN sensitivity (HOMA-IR) improved for both training groups (Δ −2.78 ± 3.48 units; p < 0.05) compared to CON. Conclusion HIIT may be an effective short-term strategy to improve cardiorespiratory fitness and IN sensitivity in overweight males. PMID:25913937
Vossen, Catherine J.; Vossen, Helen G. M.; Marcus, Marco A. E.; van Os, Jim; Lousberg, Richel
2013-01-01
In analyzing time-locked event-related potentials (ERPs), many studies have focused on specific peaks and their differences between experimental conditions. In theory, each latency point after a stimulus contains potentially meaningful information, regardless of whether it is peak-related. Based on this assumption, we introduce a new concept which allows for flexible investigation of the whole epoch and does not primarily focus on peaks and their corresponding latencies. For each trial, the entire epoch is partitioned into event-related fixed-interval areas under the curve (ERFIAs). These ERFIAs, obtained at single trial level, act as dependent variables in a multilevel random regression analysis. The ERFIA multilevel method was tested in an existing ERP dataset of 85 healthy subjects, who underwent a rating paradigm of 150 painful and non-painful somatosensory electrical stimuli. We modeled the variability of each consecutive ERFIA with a set of predictor variables among which were stimulus intensity and stimulus number. Furthermore, we corrected for latency variations of the P2 (260 ms). With respect to known relationships between stimulus intensity, habituation, and pain-related somatosensory ERP, the ERFIA method generated highly comparable results to those of commonly used methods. Notably, effects on stimulus intensity and habituation were also observed in non-peak-related latency ranges. Further, cortical processing of actual stimulus intensity depended on the intensity of the previous stimulus, which may reflect pain-memory processing. In conclusion, the ERFIA multilevel method is a promising tool that can be used to study event-related cortical processing. PMID:24224018
An Analysis of Intensive Mode Pedagogy in Management Education in India
ERIC Educational Resources Information Center
Mishra, Sita; Nargundkar, Rajendra
2015-01-01
Purpose: Management education is at its peak in India. But pedagogy and modes of delivery are not always innovative compared to top international Business Schools. It is through experimentation that the paper may be able to discover what works best in our context. The purpose of this paper is to determine the effectiveness of intensive mode of…
The high intensity solar cell: Key to low cost photovoltaic power
NASA Technical Reports Server (NTRS)
Sater, B. L.; Goradia, C.
1975-01-01
The design considerations and performance characteristics of the 'high intensity' (HI) solar cell are presented. A high intensity solar system was analyzed to determine its cost effectiveness and to assess the benefits of further improving HI cell efficiency. It is shown that residential sized systems can be produced at less than $1000/kW peak electric power. Due to their superior high intensity performance characteristics compared to the conventional and VMJ cells, HI cells and light concentrators may be the key to low cost photovoltaic power.
Cubison, M. J.; Jimenez, J. L.
2015-06-05
Least-squares fitting of overlapping peaks is often needed to separately quantify ions in high-resolution mass spectrometer data. A statistical simulation approach is used to assess the statistical precision of the retrieved peak intensities. The sensitivity of the fitted peak intensities to statistical noise due to ion counting is probed for synthetic data systems consisting of two overlapping ion peaks whose positions are pre-defined and fixed in the fitting procedure. The fitted intensities are sensitive to imperfections in the m/Q calibration. These propagate as a limiting precision in the fitted intensities that may greatly exceed the precision arising from counting statistics.more » The precision on the fitted peak intensity falls into one of three regimes. In the "counting-limited regime" (regime I), above a peak separation χ ~ 2 to 3 half-widths at half-maximum (HWHM), the intensity precision is similar to that due to counting error for an isolated ion. For smaller χ and higher ion counts (~ 1000 and higher), the intensity precision rapidly degrades as the peak separation is reduced ("calibration-limited regime", regime II). Alternatively for χ < 1.6 but lower ion counts (e.g. 10–100) the intensity precision is dominated by the additional ion count noise from the overlapping ion and is not affected by the imprecision in the m/Q calibration ("overlapping-limited regime", regime III). The transition between the counting and m/Q calibration-limited regimes is shown to be weakly dependent on resolving power and data spacing and can thus be approximated by a simple parameterisation based only on peak intensity ratios and separation. A simple equation can be used to find potentially problematic ion pairs when evaluating results from fitted spectra containing many ions. Longer integration times can improve the precision in regimes I and III, but a given ion pair can only be moved out of regime II through increased spectrometer resolving power. As a result, studies presenting data obtained from least-squares fitting procedures applied to mass spectral peaks should explicitly consider these limits on statistical precision.« less
Attentional bias to emotional stimuli is altered during moderate- but not high-intensity exercise.
Tian, Qu; Smith, J Carson
2011-12-01
Little is known regarding how attention to emotional stimuli is affected during simultaneously performed exercise. Attentional biases to emotional face stimuli were assessed in 34 college students (17 women) using the dot-probe task during counterbalanced conditions of moderate- (heart rate at 45% peak oxygen consumption) and high-intensity exercise (heart rate at 80% peak oxygen consumption) compared with seated rest. The dot-probe task consisted of 1 emotional face (pleasant or unpleasant) paired with a neutral face for 1,000 ms; 256 trials (128 trials for each valence) were presented during each condition. Each condition lasted approximately 10 min. Participants were instructed to perform each trial of the dot-probe task as quickly and accurately as possible during the exercise and rest conditions. During moderate-intensity exercise, participants exhibited significantly greater attentional bias scores to pleasant compared with unpleasant faces (p < .01), whereas attentional bias scores to emotional faces did not differ at rest or during high-intensity exercise (p > .05). In addition, the attentional bias to unpleasant faces was significantly reduced during moderate-intensity exercise compared with that during rest (p < .05). These results provide behavioral evidence that during exercise at a moderate intensity, there is a shift in attention allocation toward pleasant emotional stimuli and away from unpleasant emotional stimuli. Future work is needed to determine whether acute exercise may be an effective treatment approach to reduce negative bias or enhance positive bias in individuals diagnosed with mood or anxiety disorders, or whether attentional bias during exercise predicts adherence to exercise. (c) 2011 APA, all rights reserved.
Average Emissivity Curve of BATSE Gamma-Ray Bursts with Different Intensities
NASA Technical Reports Server (NTRS)
Mitrofanov, Igor G.; Anfimov, Dimitrij S.; Litvak, Maxim L.; Briggs, Michael S.; Paciesas, W. S.; Pendleton, Geoffrey N.; Preece, Robert D.
1998-01-01
Six intensity groups with $/sim 150$ BATSE gamma-ray bursts each are compared using average emissivity curves. Time-stretch factors for each of the dimmer groups are estimated with respect to the brightest group. Which serves as the reference taking into account the systematics of counts-produced noise effects and choice statistics. The effect of stretching/intensity anti-correlation is found at the average back slopes of bursts with good statistical significance. A stretch factor $/sim 2$ is found between the 150 dimmest bursts with peak flux $less than 0.45$ ph cm$(exp -2)$ s$(exp -1)$, and the 147 brightest bursts with peak flux $greater than 4.1$ ph cm$(exp -2}$ s$(exp -1)$. On the other hand, only a marginally significant stretching effect $V(sub ec) 1.4$ is seen at the average rise fronts.
Zhou, Zhong-Yin; Tao, DI-DI; Cao, Ji-Wang; Luo, He-Sheng
2013-06-01
The aim of the present study was to identify a specific biological marker for the diagnosis of colorectal adenomas through the analysis of variations in serum protein profiling in colorectal adenoma patients. The study was conducted at the Renmin Hospital of Wuhan University (Wuhan, China) between September 2011 and May 2012. Surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS) was performed to compare the serum protein profiles of 50 patients with colorectal adenoma and 50 healthy individuals. The obtained protein profiles were analyzed using Biomarker Wizard software. Twenty protein peaks were identified to exhibit differences in average intensity between colorectal adenomas compared with normal controls, including peaks 8,565.84, 8,694.51 and 5,910.50 Da, in which the intensity between the patients and control individuals was significantly different. Two peaks, 8,565.84 and 8,694.51 Da, were observed to be highly expressed in the colorectal adenomas, however, expression was low in the control samples. By contrast, 5,910.50 Da expression was low in the colorectal adenomas and high in the controls. The results of the current study indicate that the three protein peaks may represent specific biomarkers for colorectal adenomas.
Bilbao, Aivett; Gibbons, Bryson C.; Slysz, Gordon W.; ...
2017-11-06
We present that the mass accuracy and peak intensity of ions detected by mass spectrometry (MS) measurements are essential to facilitate compound identification and quantitation. However, high concentration species can yield erroneous results if their ion intensities reach beyond the limits of the detection system, leading to distorted and non-ideal detector response (e.g. saturation), and largely precluding the calculation of accurate m/z and intensity values. Here we present an open source computational method to correct peaks above a defined intensity (saturated) threshold determined by the MS instrumentation such as the analog-to-digital converters or time-to-digital converters used in conjunction with time-of-flightmore » MS. Here, in this method, the isotopic envelope for each observed ion above the saturation threshold is compared to its expected theoretical isotopic distribution. The most intense isotopic peak for which saturation does not occur is then utilized to re-calculate the precursor m/z and correct the intensity, resulting in both higher mass accuracy and greater dynamic range. The benefits of this approach were evaluated with proteomic and lipidomic datasets of varying complexities. After correcting the high concentration species, reduced mass errors and enhanced dynamic range were observed for both simple and complex omic samples. Specifically, the mass error dropped by more than 50% in most cases for highly saturated species and dynamic range increased by 1–2 orders of magnitude for peptides in a blood serum sample.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bilbao, Aivett; Gibbons, Bryson C.; Slysz, Gordon W.
The mass accuracy and peak intensity of ions detected by mass spectrometry (MS) measurements are essential to facilitate compound identification and quantitation. However, high concentration species can easily cause problems if their ion intensities reach beyond the limits of the detection system, leading to distorted and non-ideal detector response (e.g. saturation), and largely precluding the calculation of accurate m/z and intensity values. Here we present an open source computational method to correct peaks above a defined intensity (saturated) threshold determined by the MS instrumentation such as the analog-to-digital converters or time-to-digital converters used in conjunction with time-of-flight MS. In thismore » method, the isotopic envelope for each observed ion above the saturation threshold is compared to its expected theoretical isotopic distribution. The most intense isotopic peak for which saturation does not occur is then utilized to re-calculate the precursor m/z and correct the intensity, resulting in both higher mass accuracy and greater dynamic range. The benefits of this approach were evaluated with proteomic and lipidomic datasets of varying complexities. After correcting the high concentration species, reduced mass errors and enhanced dynamic range were observed for both simple and complex omic samples. Specifically, the mass error dropped by more than 50% in most cases with highly saturated species and dynamic range increased by 1-2 orders of magnitude for peptides in a blood serum sample.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bilbao, Aivett; Gibbons, Bryson C.; Slysz, Gordon W.
We present that the mass accuracy and peak intensity of ions detected by mass spectrometry (MS) measurements are essential to facilitate compound identification and quantitation. However, high concentration species can yield erroneous results if their ion intensities reach beyond the limits of the detection system, leading to distorted and non-ideal detector response (e.g. saturation), and largely precluding the calculation of accurate m/z and intensity values. Here we present an open source computational method to correct peaks above a defined intensity (saturated) threshold determined by the MS instrumentation such as the analog-to-digital converters or time-to-digital converters used in conjunction with time-of-flightmore » MS. Here, in this method, the isotopic envelope for each observed ion above the saturation threshold is compared to its expected theoretical isotopic distribution. The most intense isotopic peak for which saturation does not occur is then utilized to re-calculate the precursor m/z and correct the intensity, resulting in both higher mass accuracy and greater dynamic range. The benefits of this approach were evaluated with proteomic and lipidomic datasets of varying complexities. After correcting the high concentration species, reduced mass errors and enhanced dynamic range were observed for both simple and complex omic samples. Specifically, the mass error dropped by more than 50% in most cases for highly saturated species and dynamic range increased by 1–2 orders of magnitude for peptides in a blood serum sample.« less
Huan, Tao; Li, Liang
2015-07-21
Generating precise and accurate quantitative information on metabolomic changes in comparative samples is important for metabolomics research where technical variations in the metabolomic data should be minimized in order to reveal biological changes. We report a method and software program, IsoMS-Quant, for extracting quantitative information from a metabolomic data set generated by chemical isotope labeling (CIL) liquid chromatography mass spectrometry (LC-MS). Unlike previous work of relying on mass spectral peak ratio of the highest intensity peak pair to measure relative quantity difference of a differentially labeled metabolite, this new program reconstructs the chromatographic peaks of the light- and heavy-labeled metabolite pair and then calculates the ratio of their peak areas to represent the relative concentration difference in two comparative samples. Using chromatographic peaks to perform relative quantification is shown to be more precise and accurate. IsoMS-Quant is integrated with IsoMS for picking peak pairs and Zero-fill for retrieving missing peak pairs in the initial peak pairs table generated by IsoMS to form a complete tool for processing CIL LC-MS data. This program can be freely downloaded from the www.MyCompoundID.org web site for noncommercial use.
Worden, C.B.; Wald, David J.; Rhoades, D.A.
2012-01-01
We use a database of approximately 200,000 modified Mercalli intensity (MMI) observations of California earthquakes collected from USGS "Did You Feel It?" (DYFI) reports, along with a comparable number of peak ground-motion amplitudes from California seismic networks, to develop probabilistic relationships between MMI and peak ground velocity (PGV), peak ground acceleration (PGA), and 0.3-s, 1-s, and 3-s 5% damped pseudospectral acceleration (PSA). After associating each ground-motion observation with an MMI computed from all the DYFI responses within 2 km of the observation, we derived a joint probability distribution between MMI and ground motion. We then derived reversible relationships between MMI and each ground-motion parameter by using a total least squares regression to fit a bilinear function to the median of the stacked probability distributions. Among the relationships, the fit to peak ground velocity has the smallest errors, though linear combinations of PGA and PGV give nominally better results. We also find that magnitude and distance terms reduce the overall residuals and are justifiable on an information theoretic basis. For intensities MMI≥5, our results are in close agreement with the relations of Wald, Quitoriano, Heaton, and Kanamori (1999); for lower intensities, our results fall midway between Wald, Quitoriano, Heaton, and Kanamori (1999) and those of Atkinson and Kaka (2007). The earthquakes in the study ranged in magnitude from 3.0 to 7.3, and the distances ranged from less than a kilometer to about 400 km from the source.
Shepherd, Sam O.; Wilson, Oliver J.; Adlan, Ahmed M.; Wagenmakers, Anton J. M.; Shaw, Christopher S.; Lord, Janet M.
2017-01-01
Neutrophils and monocytes are key components of the innate immune system that undergo age-associated declines in function. This study compared the impact of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on immune function in sedentary adults. Twenty-seven (43 ± 11 years) healthy sedentary adults were randomized into ten weeks of either a HIIT (>90% maximum heart rate) or MICT (70% maximum heart rate) group training program. Aerobic capacity (VO2peak), neutrophil and monocyte bacterial phagocytosis and oxidative burst, cell surface receptor expression, and systemic inflammation were measured before and after the training. Total exercise time commitment was 57% less for HIIT compared to that for MICT while both significantly improved VO2peak similarly. Neutrophil phagocytosis and oxidative burst and monocyte phagocytosis and percentage of monocytes producing an oxidative burst were improved by training similarly in both groups. Expression of monocyte but not neutrophil CD16, TLR2, and TLR4 was reduced by training similarly in both groups. No differences in systemic inflammation were observed for training; however, leptin was reduced in the MICT group only. With similar immune-enhancing effects for HIIT compared to those for MICT at 50% of the time commitment, our results support HIIT as a time efficient exercise option to improve neutrophil and monocyte function. PMID:28656073
Safarimosavi, Saleh; Mohebbi, Hamid; Rohani, Hadi
2018-06-22
Safarimosavi, S, Mohebbi, H, and Rohani, H. High-intensity interval vs. continuous endurance training: Preventive effects on hormonal changes and physiological adaptations in prediabetes patients. J Strength Cond Res XX(X): 000-000, 2018-The aim of this study was to examine the effects of a 12-week high-intensity interval training (HIIT) intervention, or an isocaloric continuous endurance training (CET) intervention on insulin resistance indices and change in irisin and preptin in patients with prediabetes. Thirty-two prediabetic male patients (age = 38.7 ± 4; body mass index = 26.9 ± 1.4 kg·m; and V[Combining Dot Above]O2peak = 2.49 ± 0.22 L·min) were randomly assigned into 3 training groups (N = 8). These groups were matched based on the required energy expenditure (EE) for completing each protocol: (a) HIIT (10 × 60 seconds at 90% peak oxygen uptake [V[Combining Dot Above]O2peak], 1: 1 work to recovery at 50 W), (b) CET at an intensity equivalent to maximal fat oxidation (Fatmax) (CETFAT) (pedaling for a duration that expends an equivalent EE to an HIIT session [E ≈ HIIT]), (c) CET at an intensity equivalent to anaerobic threshold (CETAT) (E ≈ HIIT), and (d) the control group (CON): continued to perform their daily activities. After intervention, blood glucose levels were significantly (p < 0.05) lower in the HIIT group compared with CETAT group. Exercise training improved the insulin resistance index by 35, 28, and 37% in CETFAT, CETAT, and HIIT groups, respectively. Irisin concentrations in the HIIT and CETAT groups was significantly (p < 0.05) decreased compared with the pre-training values. Also, HIIT and CETFAT resulted in significant (p < 0.05) changes in preptin concentration compared with baseline. This study demonstrated that both HIIT and CETFAT protocols had similar effects on the insulin resistance index of prediabetic patients. Also, the intensity and type of exercise were effective factors in changing irisin and preptin concentrations.
Marsden, K R; Haykowsky, M J; Smirl, J D; Jones, H; Nelson, M D; Altamirano-Diaz, Luis A; Gelinas, J C; Tzeng, Y C; Smith, K J; Willie, C K; Bailey, D M; Ainslie, P N
2012-06-01
Cerebral blood flow (CBF) increases from rest to ∼60% of peak oxygen uptake (VO(2peak)) and thereafter decreases towards baseline due to hyperventilation-induced hypocapnia and subsequent cerebral vasoconstriction. It is unknown what happens to CBF in older adults (OA), who experience a decline in CBF at rest coupled with a blunted ventilatory response during VO(2peak). In 14 OA (71 ± 10 year) and 21 young controls (YA; 23 ± 4 years), we hypothesized that OA would experience less hyperventilation-induced cerebral vasoconstriction and therefore an attenuated reduction in CBF at VO(2peak). Incremental exercise was performed on a cycle ergometer, whilst bilateral middle cerebral artery blood flow velocity (MCA V (mean); transcranial Doppler ultrasound), heart rate (HR; ECG) and end-tidal PCO(2) (P(ET)CO(2)) were monitored continuously. Blood pressure (BP) was monitored intermittently. From rest to 50% of VO(2peak), despite greater elevations in BP in OA, the change in MCA V(mean) was greater in YA compared to OA (28% vs. 15%, respectively; P < 0.0005). In the YA, at intensities >70% of VO(2peak), the hyperventilation-induced declines in both P(ET)CO(2) (14 mmHg (YA) vs. 4 mmHg (OA); P < 0.05) and MCA V(mean) (-21% (YA) vs. -7% (OA); P < 0.0005) were greater in YA compared to OA. Our findings show (1), from rest-to-mild intensity exercise (50% VO(2peak)), elevations in CBF are reduced in OA and (2) age-related declines in hyperventilation during maximal exercise result in less hypocapnic-induced cerebral vasoconstriction.
Comparison of responses to two high-intensity intermittent exercise protocols.
Gist, Nicholas H; Freese, Eric C; Cureton, Kirk J
2014-11-01
The purpose of this study was to compare peak cardiorespiratory, metabolic, and perceptual responses to acute bouts of sprint interval cycling (SIC) and a high-intensity intermittent calisthenics (HIC) protocol consisting of modified "burpees." Eleven (8 men and 3 women) moderately trained, college-aged participants (age = 21.9 ± 2.1, body mass index = 24.8 ± 1.9, V[Combining Dot Above]O2peak = 54.1 ± 5.4 ml·kg·min) completed 4 testing sessions across 9 days with each session separated by 48-72 hours. Using a protocol of 4 repeated bouts of 30-second "all-out" efforts interspersed with 4-minute active recovery periods, responses to SIC and HIC were classified relative to peak values. Mean values for %V[Combining Dot Above]O2peak and %HRpeak for SIC (80.4 ± 5.3% and 86.8 ± 3.9%) and HIC (77.6 ± 6.9% and 84.6 ± 5.3%) were not significantly different (p > 0.05). Effect sizes (95% confidence interval) calculated for mean differences were: %V[Combining Dot Above]O2peak Cohen's d = 0.51 (0.48-0.53) and %HRpeak Cohen's d = 0.57 (0.55-0.59). A low-volume, high-intensity bout of repeated whole-body calisthenic exercise induced cardiovascular responses that were not significantly different but were ∼1/2SD lower than "all-out" SIC. These results suggest that in addition to the benefit of reduced time commitment, a high-intensity interval protocol of calisthenics elicits vigorous cardiorespiratory and perceptual responses and may confer physiological adaptations and performance improvements similar to those reported for SIC. The potential efficacy of this alternative interval training method provides support for its application by athletes, coaches, and strength and conditioning professionals.
Choi, Soo Jin; Yoh, Jack J
2011-08-01
A short laser pulse is irradiated on a sample to create a highly energetic plasma that emits light of a specific peak wavelength according to the material. By identifying different peaks for the analyzed samples, their chemical composition can be rapidly determined. The characteristics of the laser-induced breakdown spectroscopy (LIBS) plasma are strongly dependent on the ambient conditions. Research aimed at enhancing LIBS intensity is of great benefit in advancing LIBS for the exploration of harsh environments. By using double-pulse LIBS, the signal intensity of Al and Ca lines was enhanced by five times compared to the single-pulse signal. Also, the angles of the target and detector are adjusted to simulate samples of arbitrary shape. We verified that there exists an optimal angle at which specific elements of a test sample may be detected with stronger signal intensity. We provide several optimum configurations for the LIBS system for maximizing the signal intensity for the analysis of a nonstandard aluminum sample.
Oscillation of tissue oxygen index in non-exercising muscle during exercise.
Yano, T; Afroundeh, R; Shirakawa, K; Lian, C-S; Shibata, K; Xiao, Z; Yunoki, T
2015-09-01
The purpose of the present study was to examine how oscillation of tissue oxygen index (TOI) in non-exercising exercise is affected during high-intensity and low-intensity exercises. Three exercises were performed with exercise intensities of 30% and 70% peak oxygen uptake (Vo(2)peak) for 12 min and with exercise intensity of 70% Vo(2)peak for 30 s. TOI in non-exercising muscle (biceps brachii) during the exercises for 12 min was determined by nearinfrared spectroscopy. TOI in the non-exercising muscle during the exercises was analyzed by fast Fourier transform (FFT) to obtain power spectra density (PSD). The frequency at which maximal PSD appeared (Fmax) during the exercise with 70% Vo(2)peak for 12 min (0.00477 ± 0.00172 Hz) was significantly lower than that during the exercise with 30% Vo2peak for 12 min (0.00781 ± 0.00338 Hz). There were significant differences in blood pH and blood lactate between the exercise with 70% Vo(2)peak and the exercise with 30% Vo(2)peak. It is concluded that TOI in nonexercising muscle oscillates during low-intensity exercise as well as during high-intensity exercise and that the difference in Fmax between the two exercises is associated with the difference in increase in blood lactate derived from the exercise.
Liu, Ting; Chen, Zhong-lin; Yu, Wen-zheng; You, Shi-jie
2011-02-01
This study focuses on organic membrane foulants in a submerged membrane bioreactor (MBR) process with pre-ozonation compared to an individual MBR using three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy. While the influent was continuously ozonated at a normal dosage, preferable organic matter removal was achieved in subsequent MBR, and trans-membrane pressure increased at a much lower rate than that of the individual MBR. EEM fluorescence spectroscopy was employed to characterize the dissolved organic matter (DOM) samples, extracellular polymeric substance (EPS) samples and membrane foulants. Four main peaks could be identified from the EEM fluorescence spectra of the DOM samples in both MBRs. Two peaks were associated with the protein-like fluorophores, and the other ones were related to the humic-like fluorophores. The results indicated that pre-ozonation decreased fluorescence intensities of all peaks in the EEM spectra of influent DOM especially for protein-like substances and caused red shifts of all fluorescence peaks to different extents. The peak intensities of the protein-like substances represented by Peak T(1) and T(2) in EPS spectra were obviously decreased as a result of pre-ozonation. Both external and internal fouling could be effectively mitigated by the pre-ozonation. The most primary component of external foulants was humic acid-like substance (Peak C) in the MBR with pre-ozonation and protein-like substance (Peak T(1)) in the individual MBR, respectively. The content decrease of protein-like substances and structural change of humic-like substances were observed in external foulants from EEM fluorescence spectra due to pre-ozonation. However, it could be seen that ozonation resulted in significant reduction of intensities but little location shift of all peaks in EEM fluorescence spectra of internal foulants. Copyright © 2010 Elsevier Ltd. All rights reserved.
Craig, Jesse C; Broxterman, Ryan M; Smith, Joshua R; Allen, Jason David; Barstow, Thomas J
2018-05-03
Dietary nitrate supplementation has positive effects on mitochondrial and muscle contractile efficiency during large muscle mass exercise in humans, and on skeletal muscle blood flow (Q̇) in rats. However, concurrent measurement of these effects has not been performed in humans. Therefore, we assessed the influence of nitrate supplementation on Q̇ and muscle oxygenation characteristics during moderate (40%peak) and severe (85%peak) intensity handgrip exercise in a randomized, double-blind, crossover-design. Nine healthy men (age: 25{plus minus}2 yrs) completed four constant-power exercise tests (two per intensity) randomly assigned to condition (nitrate-rich (Nitrate) or nitrate-poor (Placebo) beetroot supplementation) and intensity (40%peak or 85%peak). Resting mean arterial pressure was lower after Nitrate compared to Placebo (84{plus minus}4 vs 89{plus minus}4 mmHg; p<0.01). All subjects were able to sustain 10 min of exercise at 40%peak in both conditions. Nitrate had no effect on exercise tolerance during 85%peak (Nitrate: 358{plus minus}29, Placebo: 341{plus minus}34 s; p=0.3). Brachial artery Q̇ was not different after Nitrate at rest or any time during exercise. Deoxygenated-[hemoglobin+myoglobin] was not different for 40%peak (p>0.05), but was elevated throughout 85%peak (p<0.05) after Nitrate. The metabolic cost (V̇O2) was not different at end exercise, however, the V̇O 2 primary amplitude at the onset of exercise was elevated after Nitrate for the 85%peak work rate (96{plus minus}20 vs 72{plus minus}12 ml/min; p<0.05) and had a faster response. These findings suggest that an acute dose of Nitrate reduces resting blood pressure and speeds V̇O 2 kinetics in young adults, but does not augment Q̇ or reduce steady-state V̇O 2 during small muscle mass handgrip exercise.
Expression Profiling of Nonpolar Lipids in Meibum From Patients With Dry Eye: A Pilot Study
Chen, Jianzhong; Keirsey, Jeremy K.; Green, Kari B.; Nichols, Kelly K.
2017-01-01
Purpose The purpose of this investigation was to characterize differentially expressed lipids in meibum samples from patients with dry eye disease (DED) in order to better understand the underlying pathologic mechanisms. Methods Meibum samples were collected from postmenopausal women with DED (PW-DED; n = 5) and a control group of postmenopausal women without DED (n = 4). Lipid profiles were analyzed by direct infusion full-scan electrospray ionization mass spectrometry (ESI-MS). An initial analysis of 145 representative peaks from four classes of lipids in PW-DED samples revealed that additional manual corrections for peak overlap and isotopes only slightly affected the statistical analysis. Therefore, analysis of uncorrected data, which can be applied to a greater number of peaks, was used to compare more than 500 lipid peaks common to PW-DED and control samples. Statistical analysis of peak intensities identified several lipid species that differed significantly between the two groups. Data from contact lens wearers with DED (CL-DED; n = 5) were also analyzed. Results Many species of the two types of diesters (DE) and very long chain wax esters (WE) were decreased by ∼20% in PW-DED, whereas levels of triacylglycerols were increased by an average of 39% ± 3% in meibum from PW-DED compared to that in the control group. Approximately the same reduction (20%) of similar DE and WE was observed for CL-DED. Conclusions Statistical analysis of peak intensities from direct infusion ESI-MS results identified differentially expressed lipids in meibum from dry eye patients. Further studies are warranted to support these findings. PMID:28426869
Teixeira-Coelho, Francisco; Fonseca, Cletiana Gonçalves; Barbosa, Nicolas Henrique Santos; Vaz, Filipe Ferreira; Cordeiro, Letícia Maria de Souza; Coimbra, Cândido Celso; Pires, Washington; Soares, Danusa Dias; Wanner, Samuel Penna
2017-01-01
This study investigated the effects of manipulating the load components of aerobic training sessions on the physical performance of rats. To achieve this purpose, adult male Wistar rats were divided into four groups: an untrained control (CON) group and training groups with a predominant overload in intensity (INT) or duration (DUR) or alternating and similar overloads in intensity and duration (ID). Prior to, during, and after 8 weeks of the control or training protocols, the performance of the rats (evaluated by their workload) was determined during fatiguing, incremental-speed treadmill running. Two additional incremental running tests were performed prior to and at the end of the protocols to measure the peak rate of oxygen consumption (VO2peak). As expected, the rats in the trained groups exhibited increased performance, whereas the untrained rats showed stable performance throughout the 8 weeks. Notably, the performance gain exhibited by the DUR rats reached a plateau after the 4th week. This plateau was not present in the INT or ID rats, which exhibited increased performance at the end of training protocol compared with the DUR rats. None of the training protocols changed the VO2peak values; however, these values were attained at faster speeds, which indicated increased running economy. In conclusion, our findings demonstrate that the training protocols improved the physical performance of rats, likely resulting from enhanced running economy. Furthermore, compared with overload in duration, overload in the intensity of training sessions was more effective at inducing performance improvements across the 8 weeks of the study.
Teixeira-Coelho, Francisco; Fonseca, Cletiana Gonçalves; Barbosa, Nicolas Henrique Santos; Vaz, Filipe Ferreira; Cordeiro, Letícia Maria de Souza; Coimbra, Cândido Celso; Pires, Washington; Soares, Danusa Dias
2017-01-01
This study investigated the effects of manipulating the load components of aerobic training sessions on the physical performance of rats. To achieve this purpose, adult male Wistar rats were divided into four groups: an untrained control (CON) group and training groups with a predominant overload in intensity (INT) or duration (DUR) or alternating and similar overloads in intensity and duration (ID). Prior to, during, and after 8 weeks of the control or training protocols, the performance of the rats (evaluated by their workload) was determined during fatiguing, incremental-speed treadmill running. Two additional incremental running tests were performed prior to and at the end of the protocols to measure the peak rate of oxygen consumption (VO2peak). As expected, the rats in the trained groups exhibited increased performance, whereas the untrained rats showed stable performance throughout the 8 weeks. Notably, the performance gain exhibited by the DUR rats reached a plateau after the 4th week. This plateau was not present in the INT or ID rats, which exhibited increased performance at the end of training protocol compared with the DUR rats. None of the training protocols changed the VO2peak values; however, these values were attained at faster speeds, which indicated increased running economy. In conclusion, our findings demonstrate that the training protocols improved the physical performance of rats, likely resulting from enhanced running economy. Furthermore, compared with overload in duration, overload in the intensity of training sessions was more effective at inducing performance improvements across the 8 weeks of the study. PMID:28841706
Reimann, R; Rübenthaler, J; Hristova, P; Staehler, M; Reiser, M; Clevert, D A
2015-10-16
The aim of this study was to analyze the histological subtypes of clear cell renal cell carcinoma (RCC) examined by means of contrast-enhanced ultrasound (CEUS) and a second generation blood pool agent (SonoVue®, Bracco, Milan, Italy) during the pre-operative phase. 29 patients with histologically proven subtypes of clear cell RCC were examined. A total of three patients were diagnosed with highly differentiated clear cell RCC, 21 out of 29 cases with moderately differentiated clear cell RCC and five out of 29 patients had insufficiently differentiated clear cell RCC. An experienced radiologist examined the patients with CEUS. The following parameters were analyzed: maximum signal intensity (PEAK), time elapsed until PEAK is reached (MTT), local blood flow (RBF), area under the time intensity curve (AUC) and the signal intensity (SI) during the course of time. For the groups all comparisons are made based on healthy renal parenchyma. In the clear cell RCC significant differences (significance level p < 0.05) between cancerous tissue and the healthy renal parenchyma were noticed in all four parameters. Therefore, the clear cell RCC stands out due to its reduced blood volume. However, it reached the PEAK reading relatively rapidly and its signal intensity was always lower than that of the healthy renal parenchyma. In the arterial phase retarded absorption of the contrast agent was observed, followed by fast washing out of the contrast agent bubbles.In all three histological subgroups no significant differences were noticed in PEAK and SI. However, the diagrams showed the possible bias, that the group of the insufficiently differentiated clear cell RCC had the highest PEAK-value and the highest signal intensity when compared with highly and moderately differentiated clear cell RCC. Our study suggests that CEUS may be an additional tool for non-invasive characterisation and differentiation of the three histological subtypes of clear cell RCC. Furthermore, it seems to have an additional diagnostic value in daily clinical.
Tan, Bing; Huang, Min; Zhu, Qibing; Guo, Ya; Qin, Jianwei
2017-09-01
The laser induced breakdown spectroscopy (LIBS) technique is an effective method to detect material composition by obtaining the plasma emission spectrum. The overlapping peaks in the spectrum are a fundamental problem in the qualitative and quantitative analysis of LIBS. Based on a curve fitting method, this paper studies an error compensation method to achieve the decomposition and correction of overlapping peaks. The vital step is that the fitting residual is fed back to the overlapping peaks and performs multiple curve fitting processes to obtain a lower residual result. For the quantitative experiments of Cu, the Cu-Fe overlapping peaks in the range of 321-327 nm obtained from the LIBS spectrum of five different concentrations of CuSO 4 ·5H 2 O solution were decomposed and corrected using curve fitting and error compensation methods. Compared with the curve fitting method, the error compensation reduced the fitting residual about 18.12-32.64% and improved the correlation about 0.86-1.82%. Then, the calibration curve between the intensity and concentration of the Cu was established. It can be seen that the error compensation method exhibits a higher linear correlation between the intensity and concentration of Cu, which can be applied to the decomposition and correction of overlapping peaks in the LIBS spectrum.
NASA Astrophysics Data System (ADS)
Wei, Qingyang; Dai, Tiantian; Ma, Tianyu; Liu, Yaqiang; Gu, Yu
2016-10-01
An Anger-logic based pixelated PET detector block requires a crystal position map (CPM) to assign the position of each detected event to a most probable crystal index. Accurate assignments are crucial to PET imaging performance. In this paper, we present a novel automatic approach to generate the CPMs for dual-layer offset (DLO) PET detectors using a stratified peak tracking method. In which, the top and bottom layers are distinguished by their intensity difference and the peaks of the top and bottom layers are tracked based on a singular value decomposition (SVD) and mean-shift algorithm in succession. The CPM is created by classifying each pixel to its nearest peak and assigning the pixel with the crystal index of that peak. A Matlab-based graphical user interface program was developed including the automatic algorithm and a manual interaction procedure. The algorithm was tested for three DLO PET detector blocks. Results show that the proposed method exhibits good performance as well as robustness for all the three blocks. Compared to the existing methods, our approach can directly distinguish the layer and crystal indices using the information of intensity and offset grid pattern.
Ristivojević, Petar; Trifković, Jelena; Vovk, Irena; Milojković-Opsenica, Dušanka
2017-01-01
Considering the introduction of phytochemical fingerprint analysis, as a method of screening the complex natural products for the presence of most bioactive compounds, use of chemometric classification methods, application of powerful scanning and image capturing and processing devices and algorithms, advancement in development of novel stationary phases as well as various separation modalities, high-performance thin-layer chromatography (HPTLC) fingerprinting is becoming attractive and fruitful field of separation science. Multivariate image analysis is crucial in the light of proper data acquisition. In a current study, different image processing procedures were studied and compared in detail on the example of HPTLC chromatograms of plant resins. In that sense, obtained variables such as gray intensities of pixels along the solvent front, peak area and mean values of peak were used as input data and compared to obtained best classification models. Important steps in image analysis, baseline removal, denoising, target peak alignment and normalization were pointed out. Numerical data set based on mean value of selected bands and intensities of pixels along the solvent front proved to be the most convenient for planar-chromatographic profiling, although required at least the basic knowledge on image processing methodology, and could be proposed for further investigation in HPLTC fingerprinting. Copyright © 2016 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Ji, Shude; Yang, Zhanpeng; Wen, Quan; Yue, Yumei; Zhang, Liguo
2018-04-01
Trailing intensive cooling with liquid nitrogen has successfully applied to friction stir welding of 2 mm thick 2060 Al-Li alloy. Welding temperature, plastic strain, residual stress and distortion of 2060 Al-Li alloy butt-joint are compared and discussed between conventional cooling and trailing intensive cooling using experimental and numerical simulation methods. The results reveal that trailing intensive cooling is beneficial to shrink high temperature area, reduce peak temperature and decrease plastic strain during friction stir welding process. In addition, the reduction degree of plastic strain outside weld is smaller than that inside weld. Welding distortion presents an anti-saddle shape. Compared with conventional cooling, the reductions of welding distortion and longitudinal residual stresses of welding joint under intense cooling reach 47.7 % and 23.8 %, respectively.
NASA Technical Reports Server (NTRS)
Kersten, K.; Cattell, C. A.; Breneman, A.; Goetz, K.; Kellogg, P. J.; Wygant, J. R.; Wilson, L. B., III; Blake, J. B.; Looper, M. D.; Roth, I.
2011-01-01
We present multi-satellite observations of large amplitude radiation belt whistler-mode waves and relativistic electron precipitation. On separate occasions during the Wind petal orbits and STEREO phasing orbits, Wind and STEREO recorded intense whistler-mode waves in the outer nightside equatorial radiation belt with peak-to-peak amplitudes exceeding 300 mV/m. During these intervals of intense wave activity, SAMPEX recorded relativistic electron microbursts in near magnetic conjunction with Wind and STEREO. This evidence of microburst precipitation occurring at the same time and at nearly the same magnetic local time and L-shell with a bursty temporal structure similar to that of the observed large amplitude wave packets suggests a causal connection between the two phenomena. Simulation studies corroborate this idea, showing that nonlinear wave.particle interactions may result in rapid energization and scattering on timescales comparable to those of the impulsive relativistic electron precipitation.
Allen, Robert C; John, Mallory G; Rutan, Sarah C; Filgueira, Marcelo R; Carr, Peter W
2012-09-07
A singular value decomposition-based background correction (SVD-BC) technique is proposed for the reduction of background contributions in online comprehensive two-dimensional liquid chromatography (LC×LC) data. The SVD-BC technique was compared to simply subtracting a blank chromatogram from a sample chromatogram and to a previously reported background correction technique for one dimensional chromatography, which uses an asymmetric weighted least squares (AWLS) approach. AWLS was the only background correction technique to completely remove the background artifacts from the samples as evaluated by visual inspection. However, the SVD-BC technique greatly reduced or eliminated the background artifacts as well and preserved the peak intensity better than AWLS. The loss in peak intensity by AWLS resulted in lower peak counts at the detection thresholds established using standards samples. However, the SVD-BC technique was found to introduce noise which led to detection of false peaks at the lower detection thresholds. As a result, the AWLS technique gave more precise peak counts than the SVD-BC technique, particularly at the lower detection thresholds. While the AWLS technique resulted in more consistent percent residual standard deviation values, a statistical improvement in peak quantification after background correction was not found regardless of the background correction technique used. Copyright © 2012 Elsevier B.V. All rights reserved.
Quantitative determination of mineral composition by powder x-ray diffraction
Pawloski, G.A.
1984-08-10
An external standard intensity ratio method is used for quantitatively determining mineralogic compositions of samples by x-ray diffraction. The method uses ratios of x-ray intensity peaks from a single run. Constants are previously determined for each mineral which is to be quantitatively measured. Ratios of the highest intensity peak of each mineral to be quantified in the sample and the highest intensity peak of a reference mineral contained in the sample are used to calculate sample composition.
Quantitative determination of mineral composition by powder X-ray diffraction
Pawloski, Gayle A.
1986-01-01
An external standard intensity ratio method is used for quantitatively determining mineralogic compositions of samples by x-ray diffraction. The method uses ratios of x-ray intensity peaks from a single run. Constants are previously determined for each mineral which is to be quantitatively measured. Ratios of the highest intensity peak of each mineral to be quantified in the sample and the highest intensity peak of a reference mineral contained in the sample are used to calculate sample composition.
Strobbe, Gregor; Carrette, Evelien; López, José David; Montes Restrepo, Victoria; Van Roost, Dirk; Meurs, Alfred; Vonck, Kristl; Boon, Paul; Vandenberghe, Stefaan; van Mierlo, Pieter
2016-01-01
Electrical source imaging of interictal spikes observed in EEG recordings of patients with refractory epilepsy provides useful information to localize the epileptogenic focus during the presurgical evaluation. However, the selection of the time points or time epochs of the spikes in order to estimate the origin of the activity remains a challenge. In this study, we consider a Bayesian EEG source imaging technique for distributed sources, i.e. the multiple volumetric sparse priors (MSVP) approach. The approach allows to estimate the time courses of the intensity of the sources corresponding with a specific time epoch of the spike. Based on presurgical averaged interictal spikes in six patients who were successfully treated with surgery, we estimated the time courses of the source intensities for three different time epochs: (i) an epoch starting 50 ms before the spike peak and ending at 50% of the spike peak during the rising phase of the spike, (ii) an epoch starting 50 ms before the spike peak and ending at the spike peak and (iii) an epoch containing the full spike time period starting 50 ms before the spike peak and ending 230 ms after the spike peak. To identify the primary source of the spike activity, the source with the maximum energy from 50 ms before the spike peak till 50% of the spike peak was subsequently selected for each of the time windows. For comparison, the activity at the spike peaks and at 50% of the peaks was localized using the LORETA inversion technique and an ECD approach. Both patient-specific spherical forward models and patient-specific 5-layered finite difference models were considered to evaluate the influence of the forward model. Based on the resected zones in each of the patients, extracted from post-operative MR images, we compared the distances to the resection border of the estimated activity. Using the spherical models, the distances to the resection border for the MSVP approach and each of the different time epochs were in the same range as the LORETA and ECD techniques. We found distances smaller than 23 mm, with robust results for all the patients. For the finite difference models, we found that the distances to the resection border for the MSVP inversions of the full spike time epochs were generally smaller compared to the MSVP inversions of the time epochs before the spike peak. The results also suggest that the inversions using the finite difference models resulted in slightly smaller distances to the resection border compared to the spherical models. The results we obtained are promising because the MSVP approach allows to study the network of the estimated source-intensities and allows to characterize the spatial extent of the underlying sources. PMID:26958464
The effects of low impact development on urban flooding under different rainfall characteristics.
Qin, Hua-peng; Li, Zhuo-xi; Fu, Guangtao
2013-11-15
Low impact development (LID) is generally regarded as a more sustainable solution for urban stormwater management than conventional urban drainage systems. However, its effects on urban flooding at a scale of urban drainage systems have not been fully understood particularly when different rainfall characteristics are considered. In this paper, using an urbanizing catchment in China as a case study, the effects of three LID techniques (swale, permeable pavement and green roof) on urban flooding are analyzed and compared with the conventional drainage system design. A range of storm events with different rainfall amounts, durations and locations of peak intensity are considered for holistic assessment of the LID techniques. The effects are measured by the total flood volume reduction during a storm event compared to the conventional drainage system design. The results obtained indicate that all three LID scenarios are more effective in flood reduction during heavier and shorter storm events. Their performance, however, varies significantly according to the location of peak intensity. That is, swales perform best during a storm event with an early peak, permeable pavements perform best with a middle peak, and green roofs perform best with a late peak, respectively. The trends of flood reduction can be explained using a newly proposed water balance method, i.e., by comparing the effective storage depth of the LID designs with the accumulative rainfall amounts at the beginning and end of flooding in the conventional drainage system. This paper provides an insight into the performance of LID designs under different rainfall characteristics, which is essential for effective urban flood management. Copyright © 2013 Elsevier Ltd. All rights reserved.
Rübenthaler, J; Reimann, R; Hristova, P; Staehler, M; Reiser, M; Clevert, D A
2015-10-16
The aim of this study was to analyse clear cell and papillary renal cell carcinoma (RCC) examined with contrast-enhanced ultrasound (CEUS) and a second generation blood pool agent (SonoVue®, Bracco, Milan, Italy) before clinical intervention. A total of 41 patients with histologically proven subtypes of RCC were examined. 29 patients had a clear cell RCC and 12 patients showed a papillary RCC. Average size in the clear cell RCC group was 6.07 cm and 1.88 cm in the papillary RCC group. An experienced radiologist examined all patients with CEUS. The following parameters were analysed: maximum signal intensity (PEAK), time elapsed until PEAK is reached (MTT), local blood flow (RBF), area under the time intensity curve (AUC) and the signal intensity (SI) during the course of time. For both groups all comparisons were made based on healthy renal parenchyma. In the clear cell RCC significant differences (significance level p < 0.05) between cancerous tissue and the healthy renal parenchyma were noticed in all four parameters. The clear cell RCC showed a significant reduced blood volume. It reached the PEAK reading relatively rapidly and its signal intensity was always lower than that of the healthy renal parenchyma. In the arterial phase retarded absorption of the contrast agent was observed, followed by fast washing out of the contrast agent bubbles.In the papillary RCC group, significant findings as to PEAK and RBF as well as a slightly significant difference as to AUC were recorded. The papillary RCC had a lower blood supply and reached its PEAK reading later. Its signal intensity was also reduced. The signal intensity of papillary NCC was significantly lower compared with clear cell RCC; absorption and washing out of the contrast agent was delayed. CEUS seems to be an useful additional method to clinically differentiate between clear cell and papillary RCC. In daily clinical use, patients with contraindication for other imaging methods, especially the magnetic resonance imaging, might particularly benefit from this method.
Woodfield, John; Zacharias, Matthew; Wilson, Genevieve; Munro, Fran; Thomas, Kate; Gray, Andrew; Baldi, James
2018-06-25
Risk factors, such as the number of pre-existing co-morbidities, the extent of the underlying pathology and the magnitude of the required operation, cannot be changed before surgery. It may, however, be possible to improve the cardiopulmonary fitness of the patient with an individualised exercise program. We are performing a randomised controlled trial (RCT) assessing the impact of High Intensity Interval Training (HIIT) on preoperative cardiopulmonary fitness and postoperative outcomes in patients undergoing major abdominal surgery. Consecutive eligible patients undergoing elective abdominal surgery are being randomised to HIIT or standard care in a 1:1 ratio. Participants allocated to HIIT will perform 14 exercise sessions on a stationary cycle ergometer, over a period of 4-6 weeks before surgery. The sessions, which are individualised, aim to start with ten repeated 1-min blocks of intense exercise with a target of reaching a heart rate exceeding 90% of the age predicted maximum, followed by 1 min of lower intensity cycling. As endurance improves, the duration of exercise is increased to achieve five 2-min intervals of high intensity exercise followed by 2 min of lower intensity cycling. Each training session lasts approximately 30 min. The primary endpoint, change in peak oxygen consumption (Peak VO 2 ) measured during cardiopulmonary exercise testing, is assessed at baseline and before surgery. Secondary endpoints include postoperative complications, length of hospital stay and three clinically validated scores: the surgical recovery scale; the postoperative morbidity survey; and the SF-36 quality of life score. The standard deviation for changes in Peak VO 2 will be assessed after the first 30 patients and will be used to calculate the required sample size. We want to assess if 14 sessions of HIIT is sufficient to improve Peak VO 2 by 2 mL/kg/min in patients undergoing major abdominal surgery and to explore the best clinical endpoint for a subsequent RCT designed to assess if improving Peak VO 2 will translate into improving clinical outcomes after surgery. Australian New Zealand Clinical Trials Registry, ACTRN12617000587303 . Registered on 26 April 2017.
NASA Technical Reports Server (NTRS)
Walter, L. S.; Doan, A. S., Jr.; Wood, F. M., Jr.; Bredekamp, J. H.
1972-01-01
A combined WDS-EDS system obviates the severe X-ray peak overlap problems encountered with Na, Mg, Al and Si common to pure EDS systems. By application of easily measured empirical correction factors for pulse pile-up and peak overlaps which are normally observed in the analysis of silicate minerals, the accuracy of analysis is comparable with that expected for WDS electron microprobe analyses. The continuum backgrounds are subtracted for the spectra by a spline fitting technique based on integrated intensities between the peaks. The preprocessed data are then reduced to chemical analyses by existing data reduction programs.
TDM interrogation of intensity-modulated USFBGs network based on multichannel lasers.
Rohollahnejad, Jalal; Xia, Li; Cheng, Rui; Ran, Yanli; Rahubadde, Udaya; Zhou, Jiaao; Zhu, Lin
2017-01-23
We report a large-scale multi-channel fiber sensing network, where ultra-short FBGs (USFBGs) instead of conventional narrow-band ultra-weak FBGs are used as the sensors. In the time division multiplexing scheme of the network, each grating response is resolved as three adjacent discrete peaks. The central wavelengths of USFBGs are tracked with the differential detection, which is achieved by calculating the peak-to-peak ratio of two maximum peaks. Compared with previous large-scale hybrid multiplexing sensing networks (e.g., WDM/TDM) which typically have relatively low interrogation speed and very high complexity, the proposed system can achieve interrogation of all channel sensors through very fast and simple intensity measurements with a broad dynamic range. A proof-of-concept experiment with twenty USFBGs, at two wavelength channels, was performed and a fast static strain measurements were demonstrated, with a high average sensitivity of ~0.54dB/µƐ and wide dynamic range of over ~3000µƐ. The channel to channel switching time was 10ms and total network interrogation time was 50ms.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Takagi, Yasumasa, E-mail: ytakagi@ims.ac.jp; Uemura, Yohei; Yokoyama, Toshihiko
2014-09-29
We have constructed an ambient pressure X-ray photoelectron spectroscopy instrument that uses hard X-ray radiation at the high-performance undulator beamline BL36XU of SPring-8. The dependence of the Au 4f peak intensity from Au foil on the ambient N{sub 2} pressure was measured. At a photon energy of 7.94 keV, the Au 4f peak intensity maintained 40% at 3000 Pa compared with that at high vacuum. We designed a polymer electrolyte fuel cell that allows us to perform X-ray photoelectron spectroscopy measurements of an electrode under working conditions. The oxidized Pt peaks were observed in the Pt 3d{sub 5/2} level of Pt nanoparticlesmore » in the cathode, and the peaks clearly depended on the applied voltage between the anode and cathode. Our apparatus can be applied as a valuable in situ tool for the investigation of the electronic states and adsorbed species of polymer electrolyte fuel cell electrode catalysts under the reaction conditions.« less
Ground motion hazard from supershear rupture
Andrews, D.J.
2010-01-01
An idealized rupture, propagating smoothly near a terminal rupture velocity, radiates energy that is focused into a beam. For rupture velocity less than the S-wave speed, radiated energy is concentrated in a beam of intense fault-normal velocity near the projection of the rupture trace. Although confined to a narrow range of azimuths, this beam diverges and attenuates. For rupture velocity greater than the S-wave speed, radiated energy is concentrated in Mach waves forming a pair of beams propagating obliquely away from the fault. These beams do not attenuate until diffraction becomes effective at large distance. Events with supershear and sub-Rayleigh rupture velocity are compared in 2D plane-strain calculations with equal stress drop, fracture energy, and rupture length; only static friction is changed to determine the rupture velocity. Peak velocity in the sub-Rayleigh case near the termination of rupture is larger than peak velocity in the Mach wave in the supershear case. The occurrence of supershear rupture propagation reduces the most intense peak ground velocity near the fault, but it increases peak velocity within a beam at greater distances.
Zhuo, Peng-ji; Zhao, Wei-hong
2009-05-01
Fluorescence excitation-emission spectroscopy (EEMS) was employed to analyze the 3-dimensional fluorescence of dissolved organic matter in the East China Sea after diatom red tide dispersion. The relationships between fluorescence peak intensity, and salinity and chlorophyll-a were discussed. The centers of protein-like fluorescence peaks dispersed at Exmax/Exmax = 270-280/290-315 nm (Peak B), 220-230/290-305 nm (Peak D), 230-240/335-350 nm (Peak S) and 280/320 nm (Peak T). Two humic-like peaks appeared at 255-270/435-480 nm (Peak A)and 330-350/420-480 nm (Peak C). High tyrosine-like intensity was observed in diatom red tide dispersion area, and tryptophan-like fluorescence was also found which was lower. High FIB/FIS showed that diatom red tide produced much tyrosine-like matter during dispersion. Peaks S, A and C had positive correlation with one another, and their distributions were similar, which decreased with distance increasing away from the shore. Good negative correlations between peaks S, A and C and salinity suggested that Jiangsu-Zhejiang coastal water was the same source of them. Correlations between fluorescence peak intensity and chlorophyll-a were not remarkable enough to clear the relationship between fluorescence and living algal matter. It was supposed that the living algal matter contributed little to the fluorescence intensity of algal dispersion seawater.
Moody, J.A.; Martin, D.A.
2001-01-01
Wildfire alters the hydrologic response of watersheds, including the peak discharges resulting from subsequent rainfall. Improving predictions of the magnitude of flooding that follows wildfire is needed because of the increase in human population at risk in the wildland-urban interface. Because this wildland-urban interface is typically in mountainous terrain, we investigated rainfall-runoff relations by measuring the maximum 30 min rainfall intensity and the unit-area peak discharge (peak discharge divided by the area burned) in three mountainous watersheds (17-26.8 km2) after a wildfire. We found rainfall-runoff relations that relate the unit-area peak discharges to the maximum 30 min rainfall intensities by a power law. These rainfall-runoff relations appear to have a threshold value for the maximum 30 min rainfall intensity (around 10 mm h-1) such that, above this threshold, the magnitude of the flood peaks increases more rapidly with increases in intensity. This rainfall intensity could be used to set threshold limits in rain gauges that are part of an early-warning flood system after wildfire. The maximum unit-area peak discharges from these three burned watersheds ranged from 3.2 to 50 m3 s-1 km-2. These values could provide initial estimates of the upper limits of runoff that can be used to predict floods after wildfires in mountainous terrain. Published in 2001 by John Wiley and Sons, Ltd.
Scribbans, Trisha D.; Edgett, Brittany A.; Vorobej, Kira; Mitchell, Andrew S.; Joanisse, Sophie D.; Matusiak, Jennifer B. L.; Parise, Gianni; Quadrilatero, Joe; Gurd, Brendon J.
2014-01-01
The current study involved the completion of two distinct experiments. Experiment 1 compared fibre specific and whole muscle responses to acute bouts of either low-volume high-intensity interval training (LV-HIT) or moderate-intensity continuous endurance exercise (END) in a randomized crossover design. Experiment 2 examined the impact of a six-week training intervention (END or LV-HIT; 4 days/week), on whole body and skeletal muscle fibre specific markers of aerobic and anaerobic capacity. Six recreationally active men (Age: 20.7±3.8 yrs; VO2peak: 51.9±5.1 mL/kg/min) reported to the lab on two separate occasions for experiment 1. Following a muscle biopsy taken in a fasted state, participants completed an acute bout of each exercise protocol (LV-HIT: 8, 20-second intervals at ∼170% of VO2peak separated by 10 seconds of rest; END: 30 minutes at ∼65% of VO2peak), immediately followed by a muscle biopsy. Glycogen content of type I and IIA fibres was significantly (p<0.05) reduced, while p-ACC was significantly increased (p<0.05) following both protocols. Nineteen recreationally active males (n = 16) and females (n = 3) were VO2peak-matched and assigned to either the LV-HIT (n = 10; 21±2 yrs) or END (n = 9; 20.7±3.8 yrs) group for experiment 2. After 6 weeks, both training protocols induced comparable increases in aerobic capacity (END: Pre: 48.3±6.0, Mid: 51.8±6.0, Post: 55.0±6.3 mL/kg/min LV-HIT: Pre: 47.9±8.1, Mid: 50.4±7.4, Post: 54.7±7.6 mL/kg/min), fibre-type specific oxidative and glycolytic capacity, glycogen and IMTG stores, and whole-muscle capillary density. Interestingly, only LV-HIT induced greater improvements in anaerobic performance and estimated whole-muscle glycolytic capacity. These results suggest that 30 minutes of END exercise at ∼65% VO2peak or 4 minutes of LV-HIT at ∼170% VO2peak induce comparable changes in the intra-myocellular environment (glycogen content and signaling activation); correspondingly, training-induced adaptations resulting for these protocols, and other HIT and END protocols are strikingly similar. PMID:24901767
Intensity matters: Therapist-dependent dose of spinal transcutaneous electrical nerve stimulation.
Serrano-Muñoz, Diego; Gómez-Soriano, Julio; Bravo-Esteban, Elisabeth; Vázquez-Fariñas, María; Taylor, Julian; Avendaño-Coy, Juan
2017-01-01
The intensity used during transcutaneous electrical nerve stimulation (TENS) in both, clinical practice and research studies, is often based on subjective commands such as "strong but comfortable sensation". There is no consensus regarding the effectiveness dose of TENS. The objective was to determine the difference in the effect of spinal TENS on soleus H-reflex modulation when applied by two therapists instructed to apply the stimulation at a "strong but comfortable" intensity. Twenty healthy volunteers divided into two groups: Therapist 1 (n = 10) and Therapist 2 (n = 10). Both therapist applied spinal TENS and sham stimulation at the T10-12 spinal level for 40min in random order to each subject, at an intensity designed to produce a "strong but comfortable" sensation. To avoid habituation, the intensity was adjusted every 2min. Soleus H-reflex was recorded before, during, and 10min after TENS by an observer blinded to the stimulus applied. Despite the instruction to apply TENS at a "strong comfortable" level, a significant difference in current density was identified: Therapist 1 (0.67mA/cm2, SD 0.54) applied more than Therapist 2 (0.53mA/cm2, SD 0.57; p<0.001) at the onset of the intervention. Maximal peak-to-peak H-reflex amplitude was inhibited significantly more 10min following TENS applied by Therapist 1 (-0.15mV, SD 0.16) compared with Therapist 2 (0.04mV, SD 0.16; p = 0.03). Furthermore, current density significantly correlated with the inhibitory effect on peak-to-peak Soleus H-reflex amplitude 10 min after stimulation (Rho = -0.38; p = 0.04). TENS intensity dosage by the therapist based on the subjective perception of the participants alone is unreliable and requires objective standardization. In addition, higher current density TENS produced greater inhibition of the Soleus H-reflex.
Intensity matters: Therapist-dependent dose of spinal transcutaneous electrical nerve stimulation
Bravo-Esteban, Elisabeth; Vázquez-Fariñas, María; Taylor, Julian
2017-01-01
The intensity used during transcutaneous electrical nerve stimulation (TENS) in both, clinical practice and research studies, is often based on subjective commands such as “strong but comfortable sensation”. There is no consensus regarding the effectiveness dose of TENS. The objective was to determine the difference in the effect of spinal TENS on soleus H-reflex modulation when applied by two therapists instructed to apply the stimulation at a “strong but comfortable” intensity. Twenty healthy volunteers divided into two groups: Therapist 1 (n = 10) and Therapist 2 (n = 10). Both therapist applied spinal TENS and sham stimulation at the T10–12 spinal level for 40min in random order to each subject, at an intensity designed to produce a “strong but comfortable” sensation. To avoid habituation, the intensity was adjusted every 2min. Soleus H-reflex was recorded before, during, and 10min after TENS by an observer blinded to the stimulus applied. Despite the instruction to apply TENS at a “strong comfortable” level, a significant difference in current density was identified: Therapist 1 (0.67mA/cm2, SD 0.54) applied more than Therapist 2 (0.53mA/cm2, SD 0.57; p<0.001) at the onset of the intervention. Maximal peak-to-peak H-reflex amplitude was inhibited significantly more 10min following TENS applied by Therapist 1 (-0.15mV, SD 0.16) compared with Therapist 2 (0.04mV, SD 0.16; p = 0.03). Furthermore, current density significantly correlated with the inhibitory effect on peak-to-peak Soleus H-reflex amplitude 10 min after stimulation (Rho = -0.38; p = 0.04). TENS intensity dosage by the therapist based on the subjective perception of the participants alone is unreliable and requires objective standardization. In addition, higher current density TENS produced greater inhibition of the Soleus H-reflex. PMID:29244850
Acute physiological responses to recreational in-line skating in young adults.
Orepic, Paula; Mikulic, Pavle; Soric, Maroje; Ruzic, Lana; Markovic, Goran
2014-01-01
We examined the physiological responses to in-line skating exercise at self-selected paces in recreationally trained adults. Seven men and 10 women performed in-line skating exercise during which oxygen uptake (VO2) and heart rate (HR) were recorded continuously. Ratings of perceived exertion (RPE) and blood lactate concentration were also obtained at the end of exercise. Furthermore, subjects' peak VO2, peak HR, RPE and gas-exchange thresholds were determined in laboratory settings. The average exercise intensity during in-line skating was 90% of peak HR, 67% of peak VO2, 84% of HR reserve and 64% of VO2 reserve. When expressed as RPE and as metabolic equivalents (METs), the average exercise intensity was 13.1 RPE and 9.4 METs. Overall, these indicators of exercise intensity categorise in-line skating at self-selected paces as a vigorous physical activity. Notably, at similar VO2 values, significantly higher HR (174 ± 16 vs. 156 ± 6 bpm; p<0.001) and RPE (13.1 ± 1.4 vs. 11.7 ± 1.4; p=0.019) were observed for in-line skating compared with treadmill running. We conclude that 1. recreational in-line skating induces physiological responses that are sufficient for improving and maintaining cardiovascular fitness in healthy adults, 2. HR- and RPE-based methods for quantifying the exercise intensity during in-line skating may overestimate the actual metabolic load and 3. the derivation of exercise prescriptions for in-line skating should be preferably based on specific (i.e. in-line skating) graded exhaustive exercise test.
Mackeen, Mukram; Almond, Andrew; Cumpstey, Ian; Enis, Seth C; Kupce, Eriks; Butters, Terry D; Fairbanks, Antony J; Dwek, Raymond A; Wormald, Mark R
2006-06-07
The experimental determination of oligosaccharide conformations has traditionally used cross-linkage 1H-1H NOE/ROEs. As relatively few NOEs are observed, to provide sufficient conformational constraints this method relies on: accurate quantification of NOE intensities (positive constraints); analysis of absent NOEs (negative constraints); and hence calculation of inter-proton distances using the two-spin approximation. We have compared the results obtained by using 1H 2D NOESY, ROESY and T-ROESY experiments at 500 and 700 MHz to determine the conformation of the terminal Glc alpha1-2Glc alpha linkage in a dodecasaccharide and a related tetrasaccharide. For the tetrasaccharide, the NOESY and ROESY spectra produced the same qualitative pattern of linkage cross-peaks but the quantitative pattern, the relative peak intensities, was different. For the dodecasaccharide, the NOESY and ROESY spectra at 500 MHz produced a different qualitative pattern of linkage cross-peaks, with fewer peaks in the NOESY spectrum. At 700 MHz, the NOESY and ROESY spectra of the dodecasaccharide produced the same qualitative pattern of peaks, but again the relative peak intensities were different. These differences are due to very significant differences in the local correlation times for different proton pairs across this glycosidic linkage. The local correlation time for each proton pair was measured using the ratio of the NOESY and T-ROESY cross-relaxation rates, leaving the NOESY and ROESY as independent data sets for calculating the inter-proton distances. The inter-proton distances calculated including the effects of differences in local correlation times give much more consistent results.
Villelabeitia-Jaureguizar, Koldobika; Vicente-Campos, Davinia; Berenguel Senen, Alejandro; Verónica Hernández Jiménez, Verónica; Lorena Ruiz Bautista, Lorena; Barrios Garrido-Lestache, María Elvira; López Chicharro, Jose
2018-05-10
Mechanical efficiency (ME) refers to the ability of an individual to transfer energy consumed by external work. A decreased ME, could represent an increased energy cost during exercise and may, therefore, be limited in terms of physical activity. This study aimed to compare the influence of two different exercise protocols: moderate continuous training (MCT) versus high intensity interval training (HIIT), as part of a cardiac rehabilitation program on ME values among coronary patients. 110 coronary patients were assigned to either HIIT or MCT groups for 8 weeks. Incremental exercise tests in a cycle ergometer were performed to obtain VO₂peak. Net energy expenditure (EE) and ME were obtained at intensities corresponding to the first (VT₁) and second (VT₂) ventilatory thresholds, and at VO₂peak. Both exercise programs significantly increase VO₂peak with a higher increase in the HIIT group (2.96 ± 2.33 mL/kg/min vs. 3.88 ± 2.40 mL/kg/min, for patients of the MCT and HIIT groups respectively, p < 0.001). The ME at VO₂peak and VT₂ only significantly increased in the HIIT group. At VT₁, ME significantly increased in both groups, with a greater increase in the HIIT group (2.20 ± 6.25% vs. 5.52 ± 5.53%, for patients of the MCT and HIIT groups respectively, p < 0.001). The application of HIIT to patients with chronic ischemic heart disease of low risk resulted in a greater improvement in VO₂peak and in ME at VT₁, than when MCT was applied. Moreover, only the application of HIIT brought about a significant increase in ME at VT₂ and at VO₂peak.
Effect of pH value of probe molecule on the graphene oxide-based surface enhanced Raman scattering
NASA Astrophysics Data System (ADS)
Cui, Shao-li; Du, Xiao-qing; Zeng, Chao; Li, Lu; Bao, Jun
2017-06-01
The dependence of graphene oxide (GO)-based surface enhanced Raman scattering (SERS) on the pH value of probe molecule was investigated. Water-soluble copper phthalocyanine (TSCuPc) was used as probe molecule and its pH value was adjusted with HCl and NaOH solution. The Raman spectra of TSCuPc with pH equaling 3, 8, and 11 on GO base were tested, respectively. The results show that both Raman enhanced intensity and full width at half maximum (FWHM) of characteristic peaks vary with the pH value of TSCuPc. It is shown that there is no obvious spectral widening of TSCuPc characteristic peaks when TSCuPc is neutral or acidic, and the chemical enhancement intensity of neutral TSCuPc on GO is biggest. In contrast, when TSCuPc is alkaline, the characteristic Raman peaks between 1350 and 1600 cm-1 of TSCuPc on GO are much wider and the intensities of characteristic peaks decrease considerably. The reasons for the pH dependence of GO-based Raman spectra were explored by comparing the wettability of molecule droplet on GO and the absorbance of different pH-adjusted TSCuPc films. It is found that the effect of molecule's pH value on SERS can be contributed to the differences of concentration and distributions on GO surface for varied pH-treated molecule.
Xiao, Chuan-Le; Chen, Xiao-Zhou; Du, Yang-Li; Sun, Xuesong; Zhang, Gong; He, Qing-Yu
2013-01-04
Mass spectrometry has become one of the most important technologies in proteomic analysis. Tandem mass spectrometry (LC-MS/MS) is a major tool for the analysis of peptide mixtures from protein samples. The key step of MS data processing is the identification of peptides from experimental spectra by searching public sequence databases. Although a number of algorithms to identify peptides from MS/MS data have been already proposed, e.g. Sequest, OMSSA, X!Tandem, Mascot, etc., they are mainly based on statistical models considering only peak-matches between experimental and theoretical spectra, but not peak intensity information. Moreover, different algorithms gave different results from the same MS data, implying their probable incompleteness and questionable reproducibility. We developed a novel peptide identification algorithm, ProVerB, based on a binomial probability distribution model of protein tandem mass spectrometry combined with a new scoring function, making full use of peak intensity information and, thus, enhancing the ability of identification. Compared with Mascot, Sequest, and SQID, ProVerB identified significantly more peptides from LC-MS/MS data sets than the current algorithms at 1% False Discovery Rate (FDR) and provided more confident peptide identifications. ProVerB is also compatible with various platforms and experimental data sets, showing its robustness and versatility. The open-source program ProVerB is available at http://bioinformatics.jnu.edu.cn/software/proverb/ .
Probing the interaction of ionic liquids with graphene using surface-enhanced Raman spectroscopy
Mahurin, Shannon Mark; Dai, Sheng; Surwade, Sumedh P.; ...
2015-12-17
We report an in situ measurement of the interaction of an imidazolium-based room temperature ionic liquid with both pure silver and a graphene-over-silver electrode under an applied electrochemical potential. At a negative applied potential, overall signal intensity increased indicating enhanced ionic liquid concentration at both silver and graphene electrodes. Vibrational modes associated with the imidazolium ring exhibited greater intensity enhancements and larger peak shifts compared with the anion indicating that the cation adsorbs with the ring and alkyl chain parallel to the electrode surface for both silver and graphene. In contrast to the silver, the surface enhanced Raman spectra ofmore » the ionic liquid near graphene showed shifts in the cation peaks even at no applied potential because of the strong π–π interaction between the ionic liquid and the graphene. Furthermore, the intensity of the graphene peak decreased in the presence of ionic liquid possibly due to the interaction between the ionic liquid and graphene. In conclusion, these results illustrate the effectiveness of surface-enhanced Raman spectroscopy to investigate electrolyte interactions with graphene at the liquid/electrode interface.« less
Time Variations in Forecasts and Occurrences of Large Solar Energetic Particle Events
NASA Astrophysics Data System (ADS)
Kahler, S. W.
2015-12-01
The onsets and development of large solar energetic (E > 10 MeV) particle (SEP) events have been characterized in many studies. The statistics of SEP event onset delay times from associated solar flares and coronal mass ejections (CMEs), which depend on solar source longitudes, can be used to provide better predictions of whether a SEP event will occur following a large flare or fast CME. In addition, size distributions of peak SEP event intensities provide a means for a probabilistic forecast of peak intensities attained in observed SEP increases. SEP event peak intensities have been compared with their rise and decay times for insight into the acceleration and transport processes. These two time scales are generally treated as independent parameters describing the development of a SEP event, but we can invoke an alternative two-parameter description based on the assumption that decay times exceed rise times for all events. These two parameters, from the well known Weibull distribution, provide an event description in terms of its basic shape and duration. We apply this distribution to several large SEP events and ask what the characteristic parameters and their dependence on source longitudes can tell us about the origins of these important events.
Ahmad, Mahmoud M; Abdel-Wahab, Essam A; El-Maaref, A A; Rawway, Mohammed; Shaaban, Essam R
2014-01-01
The irradiation effect of argon, oxygen glow discharge plasma, and mercury lamp on silver and agar/silver nanoparticle samples is studied. The irradiation time dependence of the synthesized silver and agar/silver nanoparticle absorption spectra and their antibacterial effect are studied and compared. In the agar/silver nanoparticle sample, as the irradiation time of argon glow discharge plasma or mercury lamp increases, the peak intensity and the full width at half maximum, FWHM, of the surface plasmon resonance absorption band is increased, however a decrease of the peak intensity with oxygen glow plasma has been observed. In the silver nanoparticle sample, as the irradiation time of argon, oxygen glow discharge plasma or mercury lamp increases, the peak intensity of the surface plasmon resonance absorption band is increased, however, there is no significant change in the FWHM of the surface plasmon resonance absorption band. The SEM results for both samples showed nanoparticle formation with mean size about 50 nm and 40 nm respectively. Throughout the irradiation time with the argon, oxygen glow discharge plasma or mercury lamp, the antibacterial activity of several kinds of Gram-positive and Gram-negative bacteria has been examined.
Tortorelli, R.L.
1996-01-01
The flash flood in southwestern Oklahoma City, Oklahoma, May 8, 1993, was the result of an intense 3-hour rainfall on saturated ground or impervious surfaces. The total precipitation of 5.28 inches was close to the 3-hour, 100-year frequency and produced extensive flooding. The most serious flooding was on Twin, Brock, and Lightning Creeks. Four people died in this flood. Over 1,900 structures were damaged along the 3 creeks. There were about $3 million in damages to Oklahoma City public facilities, the majority of which were in the three basins. A study was conducted to determine the magnitude of the May 8, 1993, flood peak discharge in these three creeks in southwestern Oklahoma City and compare these peaks with published flood estimates. Flood peak-discharge estimates for these creeks were determined at 11 study sites using a step-backwater analysis to match the flood water-surface profiles defined by high-water marks. The unit discharges during peak runoff ranged from 881 cubic feet per second per square mile for Lightning Creek at SW 44th Street to 3,570 cubic feet per second per square mile for Brock Creek at SW 59th Street. The ratios of the 1993 flood peak discharges to the Federal Emergency Management Agency 100-year flood peak discharges ranged from 1.25 to 3.29. The water-surface elevations ranged from 0.2 foot to 5.9 feet above the Federal Emergency Management Agency 500-year flood water-surface elevations. The very large flood peaks in these 3 small urban basins were the result of very intense rainfall in a short period of time, close to 100 percent runoff due to ground surfaces being essentially impervious, and the city streets acting as efficient conveyances to the main channels. The unit discharges compare in magnitude to other extraordinary Oklahoma urban floods.
Human brain cancer studied by resonance Raman spectroscopy
NASA Astrophysics Data System (ADS)
Zhou, Yan; Liu, Cheng-Hui; Sun, Yi; Pu, Yang; Boydston-White, Susie; Liu, Yulong; Alfano, Robert R.
2012-11-01
The resonance Raman (RR) spectra of six types of human brain tissues are examined using a confocal micro-Raman system with 532-nm excitation in vitro. Forty-three RR spectra from seven subjects are investigated. The spectral peaks from malignant meningioma, stage III (cancer), benign meningioma (benign), normal meningeal tissues (normal), glioblastoma multiforme grade IV (cancer), acoustic neuroma (benign), and pituitary adenoma (benign) are analyzed. Using a 532-nm excitation, the resonance-enhanced peak at 1548 cm-1 (amide II) is observed in all of the tissue specimens, but is not observed in the spectra collected using the nonresonance Raman system. An increase in the intensity ratio of 1587 to 1605 cm-1 is observed in the RR spectra collected from meningeal cancer tissue as compared with the spectra collected from the benign and normal meningeal tissue. The peak around 1732 cm-1 attributed to fatty acids (lipids) are diminished in the spectra collected from the meningeal cancer tumors as compared with the spectra from normal and benign tissues. The characteristic band of spectral peaks observed between 2800 and 3100 cm-1 are attributed to the vibrations of methyl (-CH3) and methylene (-CH2-) groups. The ratio of the intensities of the spectral peaks of 2935 to 2880 cm-1 from the meningeal cancer tissues is found to be lower in comparison with that of the spectral peaks from normal, and benign tissues, which may be used as a distinct marker for distinguishing cancerous tissues from normal meningeal tissues. The statistical methods of principal component analysis and the support vector machine are used to analyze the RR spectral data collected from meningeal tissues, yielding a diagnostic sensitivity of 90.9% and specificity of 100% when two principal components are used.
NASA Astrophysics Data System (ADS)
van Meerveld, Ilja; Spencer, Sheena
2017-04-01
Most studies on stemflow have focused on the amount of stemflow in different forests or for different rainfall events. So far, few studies have looked at how stemflow intensity varies during rainfall events and how peak stemflow intensities compare to peak rainfall intensities. High stemflow intensities at the base of the tree, where roots and other preferential flow pathways are prevalent, may lead to faster and deeper infiltration of stemflow than rainfall and thus affect soil moisture dynamics and potentially also subsurface stormflow generation. We measured stemflow intensities for three Western hemlock, two Western red cedar, two Douglas-fir and one Birch tree in a mature coniferous forest in coastal British Columbia to determine how stemflow intensities were related to rainfall intensity. We sprayed a blue dye tracer on two Western hemlock trees (29 and 52 cm diameter at breast height (DBH)) to determine how stemflow water flows through the soil and to what depth it infiltrates. We also applied the blue dye tracer to an area between the trees to compare infiltration of stemflow with rainfall. Stemflow increased linearly with event total precipitation for all trees. The larger trees almost exclusively had funneling ratios (i.e. the volume of stemflow per unit basal area divided by the rainfall) smaller than one, regardless of species and event size. The funneling ratios for the small trees were generally larger for larger events (up to a funneling ratio of 20) but there was considerable scatter in this relation. Trees with a DBH <35 cm, which represent 24% of the total basal area of the study site, contributed 72% of the estimated total stemflow amount. Stemflow intensities (volume of stemflow per unit basal area per hour) often increased in a stepwise manner. When there were two precipitation bursts, stemflow intensity was usually highest during the second precipitation burst. However, when there were several hours of very low rainfall intensity between consecutive precipitation bursts, stemflow intensity was lower during the first burst after the break in rainfall. Peak stemflow intensities were higher than the maximum precipitation intensity. The blue dye that was applied to the tree stems was found more frequently at depth than near the soil surface. Stemflow flowed primarily through the 10 cm organic rich upper layer of the soil around the tree before flowing between or along live and dead roots, inside dead roots, around rocks and boulders deeper into the soil. Lateral flow was observed above a dense clay layer but where roots were able to penetrate the clay layer, the infiltrating water flowed deeper into the soil and (almost) reached the soil-bedrock interface. Stemflow appeared to infiltrate deeper (122 cm) than rainfall (85 cm) but this difference was in part due to variations in maximum soil depth. These results suggest that even though stemflow is only a minor component of the water balance, the double funnelling of stemflow may significantly affect soil moisture, recharge and runoff generation.
Tsukamoto, Hayato; Suga, Tadashi; Takenaka, Saki; Tanaka, Daichi; Takeuchi, Tatsuya; Hamaoka, Takafumi; Isaka, Tadao; Hashimoto, Takeshi
2016-03-01
Aerobic moderate-intensity continuous exercise (MCE) can improve executive function (EF) acutely, potentially through the activation of both physiological and psychological factors. Recently, high-intensity interval exercise (HIIE) has been reported to be more beneficial for physical adaptation than MCE. Factors for EF improvement can potentially be more enhanced by HIIE than by MCE; but the effects of HIIE on EF remain unknown. Therefore, we aimed to examine to what extent HIIE impacts post-exercise EF immediately after exercise and during post-exercise recovery, compared with traditional MCE. Twelve healthy male subjects performed cycle ergometer exercise based on either HIIE or MCE protocols in a randomized and counterbalanced order. The HIIE protocol consisted of four 4-min bouts at 90% of peak VO2 with 3-min active recovery at 60% of peak VO2. A volume-matched MCE protocol was applied at 60% of peak VO2. To evaluate EF, a color-words Stroop task was performed pre- and post-exercise. Improvement in EF immediately after exercise was the same for the HIIE and MCE protocols. However, the improvement of EF by HIIE was sustained during 30 min of post-exercise recovery, during which MCE returned to the pre-exercise level. The EF response in the post-exercise recovery was associated with changes in physiological and psychological responses. The present findings showed that HIIE and MCE were capable of improving EF. Moreover, HIIE could prolong improvement in EF during post-exercise recovery. For the first time, we suggest that HIIE may be more effective strategy than MCE for improving EF. Copyright © 2015 Elsevier Inc. All rights reserved.
Hughes, William E.; Ueda, Kenichi
2016-01-01
Aging is associated with attenuated contraction-induced rapid onset vasodilation (ROV). We sought to examine whether chronic exercise training would improve ROV in older adults. Additionally, we examined whether a relationship between cardiorespiratory fitness and ROV exists in young and older adults. Chronically exercise-trained older adults (n = 16; 66 ± 2 yr, mean ± SE) performed single muscle contractions in the forearm and leg at various intensities. Brachial and femoral artery diameter and blood velocity were measured using Doppler ultrasound. Vascular conductance (VC) was calculated as the quotient of blood flow (ml/min) and mean arterial pressure (mmHg). These data were compared with our previously published work from an identical protocol in 16 older untrained (66 ± 1 yr, mean ± SE) and 14 young (23 ± 1 yr) adults. Peak (ΔVCpeak) and total vasodilator (VCtotal) responses were greater in trained compared with untrained older adults across leg exercise intensities (P < 0.05). There were no differences in responses between trained older and young adults in the arm or leg at any exercise intensity (P > 0.05). Comparison of ΔVCpeak in a subset of subjects at an absolute workload in the leg revealed that trained older adults exhibited augmented responses relative to untrained older adults. Exercise capacity (V̇o2 peak) was associated with ΔVCpeak and VCtotal across arm (r = 0.59–0.64) and leg exercise intensities (r = 0.55–0.68, P < 0.05) in older adults. Our data demonstrate that 1) chronic exercise training improves ROV in the arm and leg of trained older adults, such that age-related differences in ROV are abolished, and 2) VO2peak is associated with ΔVCpeak responses in both limbs of older adults. PMID:27032899
Hughes, William E; Ueda, Kenichi; Casey, Darren P
2016-06-01
Aging is associated with attenuated contraction-induced rapid onset vasodilation (ROV). We sought to examine whether chronic exercise training would improve ROV in older adults. Additionally, we examined whether a relationship between cardiorespiratory fitness and ROV exists in young and older adults. Chronically exercise-trained older adults (n = 16; 66 ± 2 yr, mean ± SE) performed single muscle contractions in the forearm and leg at various intensities. Brachial and femoral artery diameter and blood velocity were measured using Doppler ultrasound. Vascular conductance (VC) was calculated as the quotient of blood flow (ml/min) and mean arterial pressure (mmHg). These data were compared with our previously published work from an identical protocol in 16 older untrained (66 ± 1 yr, mean ± SE) and 14 young (23 ± 1 yr) adults. Peak (ΔVCpeak) and total vasodilator (VCtotal) responses were greater in trained compared with untrained older adults across leg exercise intensities (P < 0.05). There were no differences in responses between trained older and young adults in the arm or leg at any exercise intensity (P > 0.05). Comparison of ΔVCpeak in a subset of subjects at an absolute workload in the leg revealed that trained older adults exhibited augmented responses relative to untrained older adults. Exercise capacity (V̇o2 peak) was associated with ΔVCpeak and VCtotal across arm (r = 0.59-0.64) and leg exercise intensities (r = 0.55-0.68, P < 0.05) in older adults. Our data demonstrate that 1) chronic exercise training improves ROV in the arm and leg of trained older adults, such that age-related differences in ROV are abolished, and 2) VO2peak is associated with ΔVCpeak responses in both limbs of older adults. Copyright © 2016 the American Physiological Society.
An analysis of Super typhoon Rammasun's(2014) peak intensity
NASA Astrophysics Data System (ADS)
Cai, Qinbo; Xu, Yinglong
2016-04-01
Super typhoon Rammasun (2014) made landfall over Hainan Island, China, at 0730UTC 18 July 2014. Due to the damage of the anemometers, the Automatic Weather Stations (AWS) and the bouy which by Rammasun passed, failed to obtain its peak wind. Lack of the direct evident, in real-time monitoring, its peak intensities were given by 110kts (.i.e. 60m/s)/910hPa,135kts/922hPa , and 90kts/935hPa based on Dvorak technique , which were made by China Meteorological Administration (CMA),Joint Typhoon Warning Center(JTWC), and Japan Meteorological Agency (JMA) respectively. However, a minimum pressure of 881.2hPa recorded by a barometer which located at Qixhou island (19.982︒N,111.269︒E) while Rammasun approaching, indicates that its intensity was under estimated. By using observation data such as AWS, satellite, Doppler radar and wind tower near the ground, this study performs a detail evaluation to obtain its actual intensity. At 0521UTC, Qizhou Island station recorded 881.2hPa of the minimum station pressure and 899.2hPa of minimum sea level pressure (MSLP) while the anemometer had been destroyed. These are the lowest records in Chinese history and also are ones of the global lowest pressures obtained directly by barometer. It is evident that Rammasun's eyewall did not pass across Qizhou Island directly, so the actual MSLP should be lower than 899.2hPa. By applying wind-pressure relationship, it is reckoned that the reasonable MSLP and peak wind of Rammasun should be 888hPa and 70-76m/s, which makes Rammasun the strongest typhoon ever made landfall in China's history. In order to intuitively investigate the real intensity of Ramasun, eyewall structures are compared with some historical extreme typhoons (hurricanes) such as Saomai(2006), Haiyan(2013) and Katrina(2005). Satellite images show that the dense overcast convection strength of Rammasun is stronger than those when Saomai and Katrina were in their peak intensities and before landing, but weaker than Haiyan. The advanced Dvorak Technique (ADT), which was developed by Cooperative Institute for Meteorological Satellite Studies (CIMSS) of University of Wisconsin, is used to estimate their intensities. The results show that Rammasun is significantly stronger than Saomai and Katrina in peak and before landing, but weaker than that of Haiyan. Moreover, the 891.7hPa of MSLP given by ADT is approximately the same as the estimated value of 888hPa. The study demonstrates that there the pure Dvorak technique has still limitations in operational monitoring, and presents significant insights for validation and improvement of satellite-based intensity estimates.
Laurent, C Matthew; Vervaecke, Lauren S; Kutz, Matthew R; Green, J Matthew
2014-04-01
This study examined sex-specific responses during self-paced, high-intensity interval training (HIIT). Sixteen (8 men and 8 women) individuals completed a peak oxygen uptake test and 3 treadmill HIIT sessions on separate days. The HIIT sessions consisted of six 4-minute intervals performed at the highest self-selected intensity individuals felt they could maintain. Recovery between intervals was counterbalanced and consisted of 1-, 2-, or 4-minute recovery during each trial. Relative measures of intensity, including percentage of velocity at VO2peak (vVO2peak), %VO2peak, %HRmax, and blood lactate concentration ([La]), were observed during the trials. Perceived readiness was recorded immediately before and ratings of perceived exertion (RPE) were recorded at the end of each interval with session RPE recorded after each trial. Results revealed a significant effect of sex on %vVO2peak (p < 0.01) and %HRmax (p < 0.01). Data show that across trials, men self-select higher %vVO2peak (84.5 vs. 80.7%), whereas women produce higher %HRmax (96.9 vs. 92.1%) and %VO2peak (89.6 vs. 86.1%) with no difference in [La] or perceptual responses. These findings support the notion that women may demonstrate improved recovery during high-intensity exercise, as they will self-select intensities resulting in greater cardiovascular strain. Moreover, results confirm previous findings suggesting that a 2:1 work-to-rest ratio is optimal during HIIT for both men and women.
Lycett, K A; Pitula, J S
2017-05-11
The blue crab Callinectes sapidus has seen a general decline in population levels. One factor influencing mortality is infections by Hematodinium perezi, a dinoflagellate parasite. A 2 yr study was conducted in 2014 and 2015 to monitor H. perezi DNA within the Maryland (USA) coastal bays, comparing seasonal cycles in the abundance of parasite DNA in environmental samples to parasite presence in host blue crabs. A late summer to early fall peak in H. perezi infections in blue crabs was observed, consistent with previous work. Infection intensities matched this trend, showing a slow progression of low intensity infections early in the year, with a peak in moderate and heavy infections occurring between July and September, for both years. It was hypothesized that the peak in water column occurrence would coincide with those months when infection intensities were highest in blue crabs. As the peaks in water column occurrence were in July 2014 and August-September 2015, this is consistent with sporulation being the primary contributor to environmental detection in summer months. An additional peak in environmental detection occurred in both years during the early spring months, the cause of which is currently unknown but may be related to infections in overwintering crabs or alternate hosts. Several new crustacean hosts were identified within this estuary, including grass shrimp Palaemonetes spp. and the sand shrimp Crangon septemspinosa, as well as the mud crab Dyspanopeus sayi. Improved knowledge of this disease system will allow for better management of this important fishery.
NASA Technical Reports Server (NTRS)
Brickhouse, Nancy; Esser, Ruth; Habbal, Shadia R.
1995-01-01
The electron temperature in the inner corona can be derived from spectral line intensity measurements by comparing the ratio of the measured intensities of two spectral lines to the ratio calculated from theoretical models. In a homogeneous plasma the line ratio technique can be used for any two lines if the ratio of the intensities is independent of the density. The corona, however, is far from homogeneous. Even large coronal holes present at the solar poles at solar minimum can be partly or completely obscured by emission from hotter and denser surrounding regions. In this paper we investigate the effect of these surrounding regions on coronal hole temperatures. using daily intensity measurements at 1.15 Rs of the Fe XIV 5303 A and Fe X 6374 A spectral lines carried out at the National Solar Observatory at Sacramento Peak. We show that the temperatures derived using the line ratio technique for these two spectral lines can vary by more than 0.8 x 10(exp 6) K due to the contribution from surrounding regions. This example demonstrates the inadequacy of spectral lines with widely separate peak temperatures for temperature diagnostic.
Liu, Lizhen; Qin, Boqiang; Zhang, Yunlin; Zhu, Guangwei; Gao, Guang; Huang, Qi; Yao, Xin
2014-08-01
Preliminary characterization of bound extracellular polymeric substances (bEPS) of cyanobacteria is crucial to obtain a better understanding of the formation mechanism of cyanobacterial bloom. However, the characterization of bEPS can be affected by extraction methods. Five sets (including the control) of bEPS from Microcystis extracted by different methods were characterized using three-dimensional excitation and emission matrix (3DEEM) fluorescence spectroscopy combined chemical spectrophotometry; and the characterization results of bEPS samples were further compared. The agents used for extraction were NaOH, pure water and phosphate buffered saline (PBS) containing cationic exchange resins, and hot water. Extraction methods affected the fluorescence signals and intensities in the bEPS. Five fluorescence peaks were observed in the excitation and emission matrix fluorescence spectra of bEPS samples. Two peaks (peaks T₁ and T₂) present in all extractions were identified as protein-like fluorophores, two (peaks A and C) as humic-like fluorophores, and one (peak E) as a fulvic-like substance. Among these substances, the humic-like and fulvic-like fluorescences were only seen in the bEPS extracted with hot water. Also, NaOH solution extraction could result in strong fluorescence intensities compared to the other extraction methods. It was suggested that NaOH at pH10.0 was the most appropriate method to extract bEPS from Microcystis. In addition, dialysis could affect the yields and characteristics of extracted bEPS during the determination process. These results will help us to explore the issues of cyanobacterial blooms. Copyright © 2014. Published by Elsevier B.V.
Fat max as an index of aerobic exercise performance in mice during uphill running
Taniguchi, Hirokazu
2018-01-01
Endurance exercise performance has been used as a representative index in experimental animal models in the field of health sciences, exercise physiology, comparative physiology, food function or nutritional physiology. The objective of the present study was to evaluate the effectiveness of Fatmax (the exercise intensity that elicits maximal fat oxidation) as an additional index of endurance exercise performance that can be measured during running at submaximal exercise intensity in mice. We measured both Fatmax and Vo2 peak of trained ICR mice that voluntary exercised for 8 weeks and compared them with a sedentary group of mice at multiple inclinations of 20, 30, 40, and 50° on a treadmill. The Vo2 at Fatmax of the training group was significantly higher than that of the sedentary group at inclinations of 30 and 40° (P < 0.001). The running speed at Fatmax of the training group was significantly higher than that of the sedentary group at inclinations of 20, 30, and 40° (P < 0.05). Blood lactate levels sharply increased in the sedentary group (7.33 ± 2.58 mM) compared to the training group (3.13 ± 1.00 mM, P < 0.01) when running speeds exceeded the Fatmax of sedentary mice. Vo2 at Fatmax significantly correlated to Vo2 peak, running time to fatigue, and lactic acid level during running (P < 0.05) although the reproducibility of Vo2 peak was higher than that of Vo2 at Fatmax. In conclusion, Fatmax can be used as a functional assessment of the endurance exercise performance of mice during submaximal exercise intensity. PMID:29474428
McGregor, Gordon; Nichols, Simon; Hamborg, Thomas; Bryning, Lucy; Tudor-Edwards, Rhiannon; Markland, David; Mercer, Jenny; Birkett, Stefan; Ennis, Stuart; Powell, Richard; Begg, Brian; Haykowsky, Mark J; Banerjee, Prithwish; Ingle, Lee; Shave, Rob; Backx, Karianne
2016-11-16
Current international guidelines for cardiac rehabilitation (CR) advocate moderate-intensity exercise training (MISS, moderate-intensity steady state). This recommendation predates significant advances in medical therapy for coronary heart disease (CHD) and may not be the most appropriate strategy for the 'modern' patient with CHD. High-intensity interval training (HIIT) appears to be a safe and effective alternative, resulting in greater improvements in peak oxygen uptake (VO 2 peak ). To date, HIIT trials have predominantly been proof-of-concept studies in the laboratory setting and conducted outside the UK. The purpose of this multicentre randomised controlled trial is to compare the effects of HIIT and MISS training in patients with CHD attending UK CR programmes. This pragmatic study will randomly allocate 510 patients with CHD to 8 weeks of twice weekly HIIT or MISS training at 3 centres in the UK. HIIT will consist of 10 high-intensity (85-90% peak power output (PPO)) and 10 low-intensity (20-25% PPO) intervals, each lasting 1 min. MISS training will follow usual care recommendations, adhering to currently accepted UK guidelines (ie, >20 min continuous exercise at 40-70% heart rate reserve). Outcome measures will be assessed at baseline, 8 weeks and 12 months. The primary outcome for the trial will be change in VO 2 peak as determined by maximal cardiopulmonary exercise testing. Secondary measures will assess physiological, psychosocial and economic outcomes. The study protocol V.1.0, dated 1 February 2016, was approved by the NHS Health Research Authority, East Midlands-Leicester South Research Ethics Committee (16/EM/0079). Recruitment will start in August 2016 and will be completed in June 2018. Results will be published in peer-reviewed journals, presented at national and international scientific meetings and are expected to inform future national guidelines for exercise training in UK CR. NCT02784873; pre-results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
McGregor, Gordon; Nichols, Simon; Hamborg, Thomas; Bryning, Lucy; Tudor-Edwards, Rhiannon; Markland, David; Mercer, Jenny; Birkett, Stefan; Ennis, Stuart; Powell, Richard; Begg, Brian; Haykowsky, Mark J; Banerjee, Prithwish; Ingle, Lee; Shave, Rob; Backx, Karianne
2016-01-01
Introduction Current international guidelines for cardiac rehabilitation (CR) advocate moderate-intensity exercise training (MISS, moderate-intensity steady state). This recommendation predates significant advances in medical therapy for coronary heart disease (CHD) and may not be the most appropriate strategy for the ‘modern’ patient with CHD. High-intensity interval training (HIIT) appears to be a safe and effective alternative, resulting in greater improvements in peak oxygen uptake (VO2 peak). To date, HIIT trials have predominantly been proof-of-concept studies in the laboratory setting and conducted outside the UK. The purpose of this multicentre randomised controlled trial is to compare the effects of HIIT and MISS training in patients with CHD attending UK CR programmes. Methods and analysis This pragmatic study will randomly allocate 510 patients with CHD to 8 weeks of twice weekly HIIT or MISS training at 3 centres in the UK. HIIT will consist of 10 high-intensity (85–90% peak power output (PPO)) and 10 low-intensity (20–25% PPO) intervals, each lasting 1 min. MISS training will follow usual care recommendations, adhering to currently accepted UK guidelines (ie, >20 min continuous exercise at 40–70% heart rate reserve). Outcome measures will be assessed at baseline, 8 weeks and 12 months. The primary outcome for the trial will be change in VO2 peak as determined by maximal cardiopulmonary exercise testing. Secondary measures will assess physiological, psychosocial and economic outcomes. Ethics and dissemination The study protocol V.1.0, dated 1 February 2016, was approved by the NHS Health Research Authority, East Midlands—Leicester South Research Ethics Committee (16/EM/0079). Recruitment will start in August 2016 and will be completed in June 2018. Results will be published in peer-reviewed journals, presented at national and international scientific meetings and are expected to inform future national guidelines for exercise training in UK CR. Trial registration number NCT02784873; pre-results. PMID:27852718
Rapid ultrasonic stimulation of inflamed tissue with diagnostic intent
McClintic, Abbi M.; Dickey, Trevor C.; Gofeld, Michael; Ray Illian, P.; Kliot, Michel; Kucewicz, John C.; Loeser, John D.; Richebe, Philippe G.; Mourad, Pierre D.
2013-01-01
Previous studies have observed that individual pulses of intense focused ultrasound (iFU) applied to inflamed and normal tissue can generate sensations, where inflamed tissue responds at a lower intensity than normal tissue. It was hypothesized that successively applied iFU pulses will generate sensation in inflamed tissue at a lower intensity and dose than application of a single iFU pulse. This hypothesis was tested using an animal model of chronic inflammatory pain, created by injecting an irritant into the rat hind paw. Ultrasound pulses were applied in rapid succession or individually to rats' rear paws beginning at low peak intensities and progressing to higher peak intensities, until the rats withdrew their paws immediately after iFU application. Focused ultrasound protocols consisting of successively and rapidly applied pulses elicited inflamed paw withdrawal at lower intensity and estimated tissue displacement values than single pulse protocols. However, both successively applied pulses and single pulses produced comparable threshold acoustic dose values and estimates of temperature increases. This raises the possibility that temperature increase contributed to paw withdrawal after rapid iFU stimulation. While iFU-induction of temporal summation may also play a role, electrophysiological studies are necessary to tease out these potential contributors to iFU stimulation. PMID:23927192
Low-temperature vibrational dynamics of fused silica and binary silicate glasses
NASA Astrophysics Data System (ADS)
Cai, Ling; Shi, Ying; Hrdina, Ken; Moore, Lisa; Wu, Jingshi; Daemen, Luke L.; Cheng, Yongqiang
2018-02-01
Inelastic neutron scattering was used to study the vibrational dynamics of fused silica and its mixed binary glasses that were doped with either TiO2 or K2O . The energy transfer was measured from zero to 180 meV where the so-called Boson peaks (BP) at low energy and molecular vibrations at high energy are included. Although most of the vibrational spectra at the high energy resemble those reported in earlier literature, a defect-mode-like peak is observed for the doped binary systems near 120 meV . At very low temperature, the BP intensity increases rapidly with temperature and then, at higher temperature, the peak intensity decreases. As a result, a maximum is observed in the temperature dependence of the BP intensity. This maximum was shown in all four samples, but the pure SiO2 sample shows the highest intensity peak and the lowest temperature for peak position. Broadband energy spectra reveal a shift of intensity from BP to the more localized modes at higher energy. Temperature evolution of BP and its relationship with heat conduction and thermal expansion are discussed.
Generation of High Brightness X-rays with the PLEIADES Thomson X-ray Source
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brown, W J; Anderson, S G; Barty, C P J
2003-05-28
The use of short laser pulses to generate high peak intensity, ultra-short x-ray pulses enables exciting new experimental capabilities, such as femtosecond pump-probe experiments used to temporally resolve material structural dynamics on atomic time scales. PLEIADES (Picosecond Laser Electron InterAction for Dynamic Evaluation of Structures) is a next generation Thomson scattering x-ray source being developed at Lawrence Livermore National Laboratory (LLNL). Ultra-fast picosecond x-rays (10-200 keV) are generated by colliding an energetic electron beam (20-100 MeV) with a high intensity, sub-ps, 800 nm laser pulse. The peak brightness of the source is expected to exceed 10{sup 20} photons/s/0.1% bandwidth/mm2/mrad2. Simulationsmore » of the electron beam production, transport, and final focus are presented. Electron beam measurements, including emittance and final focus spot size are also presented and compared to simulation results. Measurements of x-ray production are also reported and compared to theoretical calculations.« less
Liu, Jian; Gao, Yun-Hua; Li, Ding-Dong; Gao, Yan-Chun; Hou, Ling-Mi; Xie, Ting
2014-01-01
To compare the value of contrast-enhanced ultrasound (CEUS) qualitative and quantitative analysis in the identification of breast tumor lumps. Qualitative and quantitative indicators of CEUS for 73 cases of breast tumor lumps were retrospectively analyzed by univariate and multivariate approaches. Logistic regression was applied and ROC curves were drawn for evaluation and comparison. The CEUS qualitative indicator-generated regression equation contained three indicators, namely enhanced homogeneity, diameter line expansion and peak intensity grading, which demonstrated prediction accuracy for benign and malignant breast tumor lumps of 91.8%; the quantitative indicator-generated regression equation only contained one indicator, namely the relative peak intensity, and its prediction accuracy was 61.5%. The corresponding areas under the ROC curve for qualitative and quantitative analyses were 91.3% and 75.7%, respectively, which exhibited a statistically significant difference by the Z test (P<0.05). The ability of CEUS qualitative analysis to identify breast tumor lumps is better than with quantitative analysis.
Optical assessment of bone bioimplants
NASA Astrophysics Data System (ADS)
Timchenko, P. E.; Timchenko, E. V.; Volova, L. T.; Dolgushkin, D. A.; Boltovskaya, V. V.; Frolov, O. O.; Fedorova, Ya. V.
2017-08-01
The results of application of the Raman spectroscopy method for the estimation of alternative sources for the production of bone spongy implants using the "Lioplast" technology, namely, the femoral heads resected in the operation of hip replacement surgery, are presented. It is shown that Raman spectroscopy can be used to estimate the component composition of the surface of bone implants during their processing. Comparing different sources of sponge bone production, no significant differences were found, but there are differences in the ratio of the intensities of the Raman peaks at wave numbers 1555 cm-1 and 1665 cm-1 corresponding to amide II and amide I, and also in the intensity of Raman peaks at wave numbers of 959 cm-1 (PO4 3- (ν1)) and 1068 cm-1 (CO3 2- (ν1) B-type substitution).
Structure and dynamics of coronal plasmas
NASA Technical Reports Server (NTRS)
Golub, Leon
1995-01-01
The Normal Incidence X-ray Telescope (NIXT) obtained a unique set of high resolution full disk solar images which were exposed simultaneously by X-rays in a passband at 63.5 A and by visible light. The perfect alignment of a photospheric visible light image with a coronal X-ray image enables us to present observations of X-ray intensity vs an accurately determined height above the visible limb. The height at which the observed X-ray intensity peak varies from 4000 km in active regions to 9000 km in quiet regions of the sun. The interpretation of the observations stems from the previously established fact that, for the coronal loops, emission in the NIXT bandpass peaks sharply just above the footpoints. Because there is not a sharp peak in the observed X-ray intensity vs off limb height, we conclude that the loop footpoints, when viewed at the limb, are obscured by absorption in chromospheric material along the line of sight. We calculate the X-ray intensity vs height predicted by a number of different idealizations of the solar atmosphere, and we compare these calculations with the observed X-ray intensity vs height. The calculations use existing coronal and chromospheric models. In order for the calculations to reproduce the observed off limb X-ray intensities, we are forced to assume an atmosphere in which the footpoints of coronal loops are interspersed along the line of sight with cooler chromospheric material extending to heights well above the loop footpoints. We argue that the absorption coefficient for NIXT X-rays by chromospheric material is roughly proportional to the neutral hydrogen density, and we estimate an average neutral hydrogen density and scale height implied by the data.
Influence of strength training intensity on subsequent recovery in elderly.
Orssatto, L B R; Moura, B M; Bezerra, E S; Andersen, L L; Oliveira, S N; Diefenthaeler, F
2018-06-01
Understanding the influence of strength training intensity on subsequent recovery in elderly is important to avoid reductions in physical function during the days following training. Twenty-two elderly were randomized in two groups: G70 (65.9 ± 4.8 years, n = 11) and G95 (66.9 ± 5.1, n = 11). Baseline tests included maximum voluntary isometric contraction (peak torque and rate of torque development - RTD), countermovement jump, and functional capacity (timed up and go, stairs ascent and descent). Then, both groups performed a single strength training session with intensities of 70% (G70) or 95% (G95) of five repetition maximum. The same tests were repeated immediately, 24 h, 48 h, and 72 h after the session. Peak torque was lower than baseline immediately after for both groups and at 24 h for G95. Compared with G70, G95 had lower peak torque at 24 h and 48 h. Countermovement jump, timed up and go, stairs ascent, and RTD at 0-50 ms only differed from baseline immediately after for both groups. RTD at 0-200 ms was lower than baseline immediately after and 24 h after the session for both groups. In conclusion, reduced physical function immediately after strength training can last for 1-2 days in elderly depending on the type of physical function and intensity of training. Higher intensity resulted in greater impairment. Exercise prescription in elderly should take this into account, e.g., by gradually increasing intensity during the first months of strength training. These results have relevance for elderly who have to be fit for work or other activities in the days following strength training. Copyright © 2018 Elsevier Inc. All rights reserved.
Micalos, P S; Harris, J; Drinkwater, E J; Cannon, J; Marino, F E
2015-11-01
The aim of this study was to evaluate the effect of aerobic exercise on perceptual and cerebro-spinal responses to graded electrocutaneous stimuli. The design comprised 2 x 30 min of cycling exercise at 30% and 70% of peak oxygen consumption (VO2 peak) on separate occasions in a counter-balanced order in 10 healthy participants. Assessment of nociceptive withdrawal reflex threshold (NWR-T), pain threshold (PT), and somatosensory evoked potentials (SEPs) to graded electrocutaneous stimuli were performed before and after exercise. Perceptual magnitude ratings and SEPs were compared at 30%PT, 60%PT, 100%PT before (Pre), 5 min after (Post1), and 15 min after (Post2) aerobic exercise. There was no difference in the NWR-T and the PT following exercise at 30% and 70% of VO2 peak. ANOVA for the perceptual response within pooled electrocutaneous stimuli show a significant main effect for time (F2,18=5.41, P=0.01) but no difference for exercise intensity (F1,9=0.02, P=0.88). Within-subject contrasts reveal trend differences between 30%PT and 100%PT for Pre-Post1 (P=0.09) and Pre-Post2 (P=0.02). ANOVA for the SEPs peak-to-peak signal amplitude (N1-P1) show significant main effect for time (F2,18=4.04, P=0.04) but no difference for exercise intensity (F1,9=1.83, P=0.21). Pairwise comparisons for time reveal differences between Pre-Post1 (P=0.06) and Pre-Post2 (P=0.01). There was a significant interaction for SEPs N1-P1 between exercise intensity and stimulus intensity (F2,18=3.56, P=0.05). These results indicate that aerobic exercise did not increase the electrocutaneous threshold for pain and the NWR-T. Aerobic exercise attenuated perceptual responses to innocuous stimuli and SEPs N1-P1 response to noxious stimuli.
Fukuda, Eriko; Uesawa, Yoshihiro; Baba, Masaki; Suzuki, Ryuichiro; Fukuda, Tatsuo; Shirataki, Yoshiaki; Okada, Yoshihito
2014-11-01
In order to identify the country of growth of Sophora flavescens by chemical fingerprinting, extracts of plants grown in China and Japan were analyzed using direct analysis in real time mass spectrometry (DART)-MS. The peaks characteristic of each country of growth were statistically analyzed using a volcano plot to summarize the relationship between the p-values of a statistical test and the magnitude of the difference in the peak intensities of the samples in the groups. Peaks with ap value < 0.05 in the t-test and a ≥ 2 absolute difference were defined as characteristic. Peaks characteristic of Chinese S. flavescens were found at m/z 439 and 440. In contrast, peaks characteristic of Japanese S. flavescens were found at m/z 313, 423, 437 and 441. The intensity of the selected peaks was similar in Japanese samples, whereas the m/z 439 peak had a significantly higher intensity than the other peaks in Chinese samples. Therefore, differences in selected peak patterns may allow identification of the country of growth of S. flavescens.
Provocative issues in heart disease prevention.
Juneau, Martin; Hayami, Douglas; Gayda, Mathieu; Lacroix, Sébastien; Nigam, Anil
2014-12-01
In this article, new areas of cardiovascular (CV) prevention and rehabilitation research are discussed: high-intensity interval training (HIIT) and new concepts in nutrition. HIIT consists of brief periods of high-intensity exercise interspersed by periods of low-intensity exercise or rest. The optimal mode according our work (15-second exercise intervals at peak power with passive recovery intervals of the same duration) is associated with longer total exercise time, similar time spent near peak oxygen uptake (VO2 peak) VO2 peak, and lesser perceived exertion relative to other protocols that use longer intervals and active recovery periods. Evidence also suggests that compared with moderate-intensity continuous exercise training, HIIT has superior effects on cardiorespiratory function and on the attenuation of multiple cardiac and peripheral abnormalities. With respect to nutrition, a growing body of evidence suggests that the gut microbiota is influenced by lifestyle choices and might play a pivotal role in modulating CV disease development. For example, recent evidence linking processed (but not unprocessed) meats to increased CV risk pointed to the gut microbial metabolite trimethylamine N-oxide as a potential culprit. In addition, altered gut microbiota could also mediate the proinflammatory and cardiometabolic abnormalities associated with excess added free sugar consumption, and in particular high-fructose corn syrup. Substantially more research is required, however, to fully understand how and which alterations in gut flora can prevent or lead to CV disease and other chronic illnesses. We conclude with thoughts about the appropriate role for HIIT in CV training and future research in the role of gut flora-directed interventions in CV prevention. Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.
How would peak rainfall intensity affect runoff predictions using conceptual water balance models?
NASA Astrophysics Data System (ADS)
Yu, B.
2015-06-01
Most hydrological models use continuous daily precipitation and potential evapotranspiration for streamflow estimation. With the projected increase in mean surface temperature, hydrological processes are set to intensify irrespective of the underlying changes to the mean precipitation. The effect of an increase in rainfall intensity on the long-term water balance is, however, not adequately accounted for in the commonly used hydrological models. This study follows from a previous comparative analysis of a non-stationary daily series of stream flow of a forested watershed (River Rimbaud) in the French Alps (area = 1.478 km2) (1966-2006). Non-stationarity in the recorded stream flow occurred as a result of a severe wild fire in 1990. Two daily models (AWBM and SimHyd) were initially calibrated for each of three distinct phases in relation to the well documented land disturbance. At the daily and monthly time scales, both models performed satisfactorily with the Nash-Sutcliffe coefficient of efficiency (NSE) varying from 0.77 to 0.92. When aggregated to the annual time scale, both models underestimated the flow by about 22% with a reduced NSE at about 0.71. Exploratory data analysis was undertaken to relate daily peak hourly rainfall intensity to the discrepancy between the observed and modelled daily runoff amount. Preliminary results show that the effect of peak hourly rainfall intensity on runoff prediction is insignificant, and model performance is unlikely to improve when peak daily precipitation is included. Trend analysis indicated that the large decrease of precipitation when daily precipitation amount exceeded 10-20 mm may have contributed greatly to the decrease in stream flow of this forested watershed.
NASA Astrophysics Data System (ADS)
Sidle, Roy C.; Ziegler, Alan D.
2017-01-01
The interception and smoothing effect of forest canopies on pulses of incident rainfall and its delivery to the soil has been suggested as a factor in moderating peak pore water pressure in soil mantles, thus reducing the risk of shallow landslides. Here we provide 3 years of rainfall and throughfall data in a tropical secondary dipterocarp forest characterized by few large trees in northern Thailand, along with selected soil moisture dynamics, to address this issue. Throughfall was an estimated 88 % of rainfall, varying from 86 to 90 % in individual years. Data from 167 events demonstrate that canopy interception was only weakly associated (via a nonlinear relationship) with total event rainfall, but not significantly correlated with duration, mean intensity, or antecedent 2-day precipitation (API2). Mean interception during small events (≤ 35 mm) was 17 % (n = 135 events) compared with only 7 % for large events (> 35 mm; n = 32). Examining small temporal intervals within the largest and highest intensity events that would potentially trigger landslides revealed complex patterns of interception. The tropical forest canopy had little smoothing effect on incident rainfall during the largest events. During events with high peak intensities, high wind speeds, and/or moderate-to-high pre-event wetting, measured throughfall was occasionally higher than rainfall during large event peaks, demonstrating limited buffering. However, in events with little wetting and low-to-moderate wind speed, early event rainfall peaks were buffered by the canopy. As rainfall continued during most large events, there was little difference between rainfall and throughfall depths. A comparison of both rainfall and throughfall depths to conservative mean intensity-duration thresholds for landslide initiation revealed that throughfall exceeded the threshold in 75 % of the events in which rainfall exceeded the threshold for both wet and dry conditions. Throughfall intensity for the 11 largest events (rainfall = 65-116 mm) plotted near or above the intensity-duration threshold for landslide initiation during wet conditions; 5 of the events were near or above the threshold for dry conditions. Soil moisture responses during large events were heavily and progressively buffered at depths of 1 to 2 m, indicating that the timescale of any short-term smoothing of peak rainfall inputs (i.e., ≤ 1 h) has little influence on peak pore water pressure at depths where landslides would initiate in this area. Given these findings, we conclude that canopy interception would have little effect on mitigating shallow landslide initiation during the types of monsoon rainfall conditions in this and similar tropical secondary forest sites.
Frey, Brian L.; Lin, Yuan; Westphall, Michael S.; Smith, Lloyd M.
2006-01-01
Charge reduction electrospray mass spectrometry (CREMS) reduces the charge states of electrospray-generated ions, which concentrates the ions from a protein into fewer peaks spread over a larger m/z range, thereby increasing peak separation and decreasing spectral congestion. An optimized design for a CREMS source is described that provides an order-of-magnitude increase in sensitivity compared to previous designs and provides control over the extent of charge reduction. Either a corona discharge or an α-particle source was employed to generate anions that abstract protons from electrosprayed protein cations. These desired ion/ion proton transfer reactions predominated, but some oxidation and ion-attachment reactions also occurred leading to new peaks or mass-shifted broader peaks while decreasing signal intensity. The species producing these deleterious side-reactions were identified, and conditions were found that prevented their formation. Spectrometer m/z biases were examined because of their effect upon the signal intensity of higher m/z charge-reduced protein ions. The utility of this atmospheric pressure CREMS was demonstrated using a cell lysate fraction from E. coli. The spectral simplification afforded by CREMS reveals more proteins than are observed without charge reduction. PMID:16198118
Discovery of Short-Timescale Oscillations in the Transition Region by CLASP
NASA Technical Reports Server (NTRS)
Kubo, M.; Katsukawa, Y.; Kano, R.; Winebarger, A.; Kobayashi, K.; Ishikawa, R.; Narukage, N.; Bando, T.; Suematsu, Y.; Giono, G.;
2017-01-01
High cadence spectroscopic observations by CLASP reveal that intensity fluctuations of blue and red peaks of the hydrogen Lyman-alpha line (121.57 nm) recurrently appear in the quiet Sun at short timescale. The intensity fluctuations of the blue and red peaks are opposite in phase to each other: the blue peak is enhanced during the decease of the red peak, and vice versa. Similar intensity fluctuations also can be seen in Mg II h & k profiles observed with IRIS. It is suggested that the short-timescale oscillatory or torsional phenomena take place in the transition region or the upper chromosphere.
Intensive Exercise Training During Bed Rest Attenuates Deconditioning
NASA Technical Reports Server (NTRS)
Greenleaf, John E.
1997-01-01
Intensive exercise training during bed rest attenuates deconditioning. Med. Sci. Sports Exerc., Vol. 29, No. 2, pp. 207-215, 1997. A 30-d 6 deg head-down bed rest project was conducted to evaluate variable high-intensity, short-duration, isotonic cycle ergometer exercise (ITE) training and high-intensity intermittent resistive isokinetic exercise (IKE) training regimens designed to maintain peak VO2 and muscle mass, strength, and endurance at ambulatory control levels throughout prolonged bed rest. Other elements of the deconditioning (adaptive) syndrome, such as proprioception, psychological performance, hypovolemia, water balance, body composition, and orthostatic tolerance, were also measured. Major findings are summarized in this paper. Compared with response during bed rest of the no exercise (NOE) control group: the ITE training regimen (a) maintained work capacity (peak VO2), (b) maintained plasma and red cell volumes, (c) induced positive body water balance, (d) decreased quality of sleep and mental concentration, and (e) had no effect on the decrease in orthostatic tolerance; the IKE training regimen (f) attenuated the decrease in peak VO2 by 50%, (g) attenuated loss of red cell volume by 40% but had no effect on loss of plasma volume, (b) induced positive body water balance, (i) had no adverse effect on quality of sleep or concentration, and 0) had no effect on the decrease in orthostatic tolerance. These findings suggest that various elements of the deconditioning syndrome can be manipulated by duration and intensity of ITE or IKE training regimens and that several different training protocols will be required to maintain or restore physiological and psychological performance of individuals confined to prolonged bed rest.
Structural and electro-optical properties of bilayer graphyne like BN sheet
NASA Astrophysics Data System (ADS)
Behzad, Somayeh
2016-12-01
The structural, electronic and optical properties of bilayer graphyne like BN sheet (BNyne) with different stacking manners have been explored by the first-principles calculations. The stabilities of α-BNyne bilayers with different stacking manners are compared. The α-BNyne Bilayers have wide band gaps. Compared to the single α-BNyne, the numbers of energy bands are doubled due to the interlayer interactions and the band gap is reduced. The AB-I configuration has a direct band gap while the band gap becomes indirect for AA-II. The calculated ε2 (ω) of bilayer α-BNyne for (Eǁx) is similar to that of the monolayer α-BNyne, except for the small changes of peak positions and increasing of peak intensities. For (Eǁz), the first absorption peak occures at 3.86 eV, and the prominant peak of monolayer at 9.17 eV becomes broadened. These changes are related to the new transitions resulting from the band splitting.
Tschakert, Gerhard; Kroepfl, Julia M.; Mueller, Alexander; Harpf, Hanns; Harpf, Leonhard; Traninger, Heimo; Wallner-Liebmann, Sandra; Stojakovic, Tatjana; Scharnagl, Hubert; Meinitzer, Andreas; Pichlhoefer, Patriz; Hofmann, Peter
2016-01-01
Despite described benefits of aerobic high-intensity interval exercise (HIIE), the acute responses during different HIIE modes and associated health risks have only been sparsely discovered in heart disease patients. Therefore, the aim of this study was to investigate the acute responses for physiological parameters, cardiovascular and inflammatory biomarkers, and catecholamines yielded by two different aerobic HIIE protocols compared to continuous exercise (CE) in phase III cardiac rehabilitation. Eight cardiac patients (7 with coronary heart disease, 1 with myocarditis; 7 males, 1 female; age: 63.0 ± 9.4 years; height: 1.74 ± 0.05 m; weight: 83.6 ± 8.7 kg), all but one treated with ß-blocking agents, performed a maximal symptom-limited incremental exercise test (IET) and three different exercise tests matched for mean load (Pmean) and total duration: 1) short HIIE with a peak workload duration (tpeak) of 20 s and a peak workload (Ppeak) equal to the maximum power output (Pmax) from IET; 2) long HIIE with a tpeak of 4 min, Ppeak was corresponding to the power output at 85 % of maximal heart rate (HRmax) from IET; 3) CE with a target workload equal to Pmean of both HIIE modes. Acute metabolic and peak cardiorespiratory responses were significantly higher during long HIIE compared to short HIIE and CE (p < 0.05) except HRpeak which tended to be higher in long HIIE than in short HIIE (p = 0.08). Between short HIIE and CE, no significant difference was found for any parameter. Acute responses of cardiovascular and inflammatory biomarkers and catecholamines didn’t show any significant difference between tests (p > 0.05). All health-related variables remained in a normal range in any test except NT-proBNP, which was already elevated at baseline. Despite a high Ppeak particularly in short HIIE, both HIIE modes were as safe and as well tolerated as moderate CE in cardiac patients by using our methodological approach. Key points High-intensity interval exercise (HIIE) with short peak workload durations (tpeak) induce a lower acute metabolic and peak cardiorespiratory response compared to intervals with long tpeak despite higher peak workload intensities and identical mean load. No significant difference for any physiological parameter was found between short HIIE and CE. Between short HIIE, long HIIE, and CE, no significant difference was found in the increase (or decrease, respectively,) of health related markers such as cardiovascular biomarkers, catecholamines, or inflammatory parameters during exercise. During all exercise modes, all risk markers remained in a normal range except for NT-proBNP which was, however, already elevated at baseline. Short HIIE, long HIIE, and CE were safely performed by patients with CHD or myocarditis in cardiac rehabilitation by using our methodological approach to exercise prescription. This approach included the prescription of exercise intensities with respect to LTP1, LTP2, and Pmax as well as a conscious setting of Pmean at a moderate level (80 % of PLTP2). Importantly, all exercise modes were matched for Pmean and exercise duration in order to enable a comparison of the three protocols. PMID:26957930
Memory Effect Manifested by a Boson Peak in Metallic Glass.
Luo, P; Li, Y Z; Bai, H Y; Wen, P; Wang, W H
2016-04-29
We explore the correlation between a boson peak and structural relaxation in a typical metallic glass. Consistent with enthalpy recovery, a boson peak shows a memory effect in an aging-and-scan procedure. Single-step isothermal aging produces a monotonic decrease of enthalpy and boson peak intensity; for double-step isothermal aging, both enthalpy and boson peak intensity experience, coincidently, an incipient increase to a maximum and a subsequent decrease toward the equilibrium state. Our results indicate a direct link between slow structural relaxation and fast boson peak dynamics, which presents a profound understanding of the two dynamic behaviors in glass.
Hottenrott, Kuno; Ludyga, Sebastian; Schulze, Stephan
2012-01-01
The aim of the study was to examine the effects of two different training programs (high-intensity-training vs. continuous endurance training) on aerobic power and body composition in recreationally active men and women and to test whether or not participants were able to complete a half marathon after the intervention period. Thirty-four recreational endurance runners were randomly assigned either to a Weekend-Group (WE, n = 17) or an After-Work- Group (AW, n = 17) for a 12 week-intervention period. WE weekly completed 2 h 30 min of continuous endurance running composed of 2 sessions on the weekend. In contrast, AW performed 4 30 min sessions of high intensity training and an additional 30 min endurance run weekly, always after work. During an exhaustive treadmill test aerobic power was measured and heart rate was continuously recorded. Body composition was assessed using bio-impedance. Following the intervention period all subjects took part in a half-marathon. AW significantly improved peak oxygen uptake (VO2 peak) from 36.8 ± 4.5 to 43.6 ± 6.5 [mL.min(-1).kg(-1)], velocity at lactate threshold (VLT) from 9.7 ± 2.2 to 11.7 ± 1.8 [km.h(-1)] and visceral fat from 5.6 ± 2.2 to 4.7 ± 1.9 In WE VO2 peak signifi-cantly increased from 38.8 ± 5.0 to 41.5 ± 6.0 [mL.min(-1).kg(-1)], VLT from 9.9 ± 1.3 to 11.2 ± 1.7 [km.h(-1)] and visceral fat was reduced from 5.7 ± 2.1 to 5.4 ± 1.9 (p < 0.01). Only the improvements of VO2 peak were significantly greater in AW compared with WE (pre/post group interaction: F=15.4, p = 0.01, η(2) = 0.36). Both groups completed a half marathon with no significant differences in performance (p = 0.63). Short, intensive endurance training sessions of about 30 min are effective in improving aerobic fitness in recreationally active runners. Key pointsContinuous endurance training and high intensity training lead to significant improvements of aerobic capacity and body compositionBoth training methods enable recreationally active runners to finish a half-marathonHigh intensity training is favorable to improve VO2 peak.
[Infrared spectroscopic study on the component and vigor analysis of Cistanche deserticola seeds].
Xu, Rong; Sun, Su-Qin; Chen, Jun; Chen, Shi-Lin; Zhou, Feng
2009-01-01
Comparative study of the different parts of cistanche deserticola seeds and their changes after different processing were examined by Fourier transform infrared spectroscopy spectra (FTIR). The results of the analysis showed that components in the cistanche deserticola seeds were abundant, which contained characteristic absorption peaks of protein, fat and carbohydrate. As well, pectin and aromatic compound can be also found in the seeds. However, the components were different in different parts of cistanche deserticola seeds. The characteristic absorption peak intensities of fat at 2,926, 1,746, 1,161 and 721 cm(-1) were the strongest in the seed kernels. However, the seed coats mainly consisted of carbohydrate and pectin, which were showed at 1,054 cm(-1). The contents of protein and carbohydrate were decreased distinctly in the moldy and dead seeds after processing. The characteristic absorption peak intensity ratio of protein to fat (I1,630/I1,745 ) was all higher than 1.05 in the live seeds. The characteristic absorption peak intensity ratio of amido link I of protein to fat (11,653/I1,745) in the dead seed kernels of the cistanche deserticola was decreased from 0.31 to 0. 23, which was 25.8% less than that in vital seed kernels. The results suggest that FTIR not only can be used in fast comprehensive analysis of seed components, but also can be used in the seed vigor analysis, seed longevity determination and seed quality evaluation.
Grade influences blood lactate kinetics during cross-country skiing.
LaRoche, Dain P; Amann, Markus; Rundell, Kenneth W
2010-01-01
The purpose of this study was to examine the effects of level vs. graded skate skiing on capillary blood lactate (B(La)), heart rate (HR), oxygen consumption (V(O2)), and training intensity prescriptions. Eleven Nordic skiers completed 2 submaximal skate roller skiing treadmill protocols during which intensity was increased either by grade (G(inc)) or by speed (S(inc)). The protocols were compared for prethreshold BLa, HR, and V(O2) at lactate threshold (LT) and the HR/V(O2) relationship. Additionally, double-pole (primarily upper body) and skating (arms and legs combined) protocols were used to measure peak V(O2) and peak HR. Heart rate and V(O2) at LT were lower during G(inc) compared with S(inc) (154.9 +/- 6.8 b.min(-1) vs. 162.0 +/- 9.1 b.min(-1) and 46.3 +/- 2.8 ml.kg(-1).min(-1) vs. 49.1 +/- 1.6 ml.kg(-1).min(-1), respectively, both p < 0.01). Pre-threshold B(La) and the HR/V(O2) relationship were not different between the submaximal protocols. V(O2) and HRpeak were higher in skating compared with double poling (64.6 +/- 1.8 ml.kg(-1).min(-1) vs. 60.3 +/- 2.8 ml.kg(-1).min(-1), 192.6 +/- 5.8 b.min(-1) vs. 187.8 +/- 6.7 b.min(-1), respectively, both p < 0.01). Greater reliance on upper-body musculature during graded skiing and its associated lower aerobic capacity increases B(La) when compared with level skiing. The leftward shift in the B(La) vs. intensity curve during uphill skiing should be recognized to properly prescribe training intensity as well as interpret laboratory results.
Robinson, Emily; Durrer, Cody; Simtchouk, Svetlana; Jung, Mary E; Bourne, Jessica E; Voth, Elizabeth; Little, Jonathan P
2015-09-01
Exercise can have anti-inflammatory effects in obesity, but the optimal type and intensity of exercise are not clear. This study compared short-term high-intensity interval training (HIIT) with moderate-intensity continuous training (MICT) in terms of improvement in cardiorespiratory fitness, markers of inflammation, and glucose control in previously inactive adults at elevated risk of developing type 2 diabetes. Thirty-nine inactive, overweight/obese adults (32 women) were randomly assigned to 10 sessions over 2 wk of progressive HIIT (n = 20, four to ten 1-min sessions at ∼90% peak heart rate, 1-min rest periods) or MICT (n = 19, 20-50 min at ∼65% peak heart rate). Before and 3 days after training, participants performed a peak O2 uptake test, and fasting blood samples were obtained. Both HIIT (1.8 ± 0.4 vs. 1.9 ± 0.4 l/min, pre vs. post) and MICT (1.8 ± 0.5 vs. 1.9 ± 0.5 l/min, pre vs. post) improved peak O2 uptake (P < 0.001) and lowered plasma fructosamine (P < 0.05). Toll-like receptor (TLR) 4 (TLR4) expression was reduced on lymphocytes and monocytes after both HIIT and MICT (P < 0.05) and on neutrophils after MICT (P < 0.01). TLR2 on lymphocytes was reduced after HIIT and MICT (P < 0.05). Plasma inflammatory cytokines were unchanged after training in both groups, but MICT led to a reduction in fasting plasma glucose (P < 0.05, 5.9 ± 1.0 vs. 5.6 ± 1.0 mmol/l, pre vs. post). Ten days of either HIIT or MICT can improve cardiorespiratory fitness and glucose control and lead to reductions in TLR2 and TLR4 expression. MICT, which involved a longer duration of exercise, may be superior for reducing fasting glucose. Copyright © 2015 the American Physiological Society.
Adams, Scott C; DeLorey, Darren S; Davenport, Margie H; Stickland, Michael K; Fairey, Adrian S; North, Scott; Szczotka, Alexander; Courneya, Kerry S
2017-10-15
Testicular cancer survivors (TCS) have an increased risk of treatment-related cardiovascular disease (CVD), which may limit their overall survival. We evaluated the effects of high-intensity aerobic interval training (HIIT) on traditional and novel CVD risk factors and surrogate markers of mortality in a population-based sample of TCS. This phase 2 trial (ClinicalTrials.gov identifier NCT02459132) randomly assigned 63 TCS to usual care (UC) or 12 weeks of supervised HIIT (ie, alternating periods of vigorous-intensity and light-intensity aerobic exercise). The primary outcome was peak aerobic fitness (VO 2peak ) assessed via a treadmill-based maximal cardiorespiratory exercise test. Secondary endpoints included CVD risk (eg, Framingham Risk Score), arterial health, parasympathetic nervous system function, and blood-based biomarkers. Postintervention VO 2peak data were obtained for 61 participants (97%). HIIT participants attended 99% of the exercise sessions and achieved 98% of the target exercise intensity. Analysis of covariance demonstrated that HIIT was superior to UC for improving VO 2peak (adjusted between-group mean difference, 3.7 mL O 2 /kg/min; 95% confidence interval, 2.4-5.1 [P<.001]) and multiple secondary outcomes including CVD risk (P = .011), arterial thickness (P<.001), arterial stiffness (P<.001), postexercise parasympathetic reactivation (P = .001), inflammation (P = .045), and low-density lipoprotein (P = .014). Overall, HIIT reduced the prevalence of modifiable CVD risk factors by 20% compared with UC. This randomized trial provides the first evidence that HIIT improves cardiorespiratory fitness, multiple pathways of CVD risk, and surrogate markers of mortality in TCS. These findings have important implications for the management of TCS. Further research concerning the long-term effects of HIIT on CVD morbidity and mortality in TCS is warranted. Cancer 2017;123:4057-65. © 2017 American Cancer Society. © 2017 American Cancer Society.
Robinson, Emily; Durrer, Cody; Simtchouk, Svetlana; Jung, Mary E.; Bourne, Jessica E.; Voth, Elizabeth
2015-01-01
Exercise can have anti-inflammatory effects in obesity, but the optimal type and intensity of exercise are not clear. This study compared short-term high-intensity interval training (HIIT) with moderate-intensity continuous training (MICT) in terms of improvement in cardiorespiratory fitness, markers of inflammation, and glucose control in previously inactive adults at elevated risk of developing type 2 diabetes. Thirty-nine inactive, overweight/obese adults (32 women) were randomly assigned to 10 sessions over 2 wk of progressive HIIT (n = 20, four to ten 1-min sessions at ∼90% peak heart rate, 1-min rest periods) or MICT (n = 19, 20-50 min at ∼65% peak heart rate). Before and 3 days after training, participants performed a peak O2 uptake test, and fasting blood samples were obtained. Both HIIT (1.8 ± 0.4 vs. 1.9 ± 0.4 l/min, pre vs. post) and MICT (1.8 ± 0.5 vs. 1.9 ± 0.5 l/min, pre vs. post) improved peak O2 uptake (P < 0.001) and lowered plasma fructosamine (P < 0.05). Toll-like receptor (TLR) 4 (TLR4) expression was reduced on lymphocytes and monocytes after both HIIT and MICT (P < 0.05) and on neutrophils after MICT (P < 0.01). TLR2 on lymphocytes was reduced after HIIT and MICT (P < 0.05). Plasma inflammatory cytokines were unchanged after training in both groups, but MICT led to a reduction in fasting plasma glucose (P < 0.05, 5.9 ± 1.0 vs. 5.6 ± 1.0 mmol/l, pre vs. post). Ten days of either HIIT or MICT can improve cardiorespiratory fitness and glucose control and lead to reductions in TLR2 and TLR4 expression. MICT, which involved a longer duration of exercise, may be superior for reducing fasting glucose. PMID:26139217
Ye, Yalan; He, Wenwen; Cheng, Yunfei; Huang, Wenxia; Zhang, Zhilin
2017-02-16
The estimation of heart rate (HR) based on wearable devices is of interest in fitness. Photoplethysmography (PPG) is a promising approach to estimate HR due to low cost; however, it is easily corrupted by motion artifacts (MA). In this work, a robust approach based on random forest is proposed for accurately estimating HR from the photoplethysmography signal contaminated by intense motion artifacts, consisting of two stages. Stage 1 proposes a hybrid method to effectively remove MA with a low computation complexity, where two MA removal algorithms are combined by an accurate binary decision algorithm whose aim is to decide whether or not to adopt the second MA removal algorithm. Stage 2 proposes a random forest-based spectral peak-tracking algorithm, whose aim is to locate the spectral peak corresponding to HR, formulating the problem of spectral peak tracking into a pattern classification problem. Experiments on the PPG datasets including 22 subjects used in the 2015 IEEE Signal Processing Cup showed that the proposed approach achieved the average absolute error of 1.65 beats per minute (BPM) on the 22 PPG datasets. Compared to state-of-the-art approaches, the proposed approach has better accuracy and robustness to intense motion artifacts, indicating its potential use in wearable sensors for health monitoring and fitness tracking.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Webb-Robertson, Bobbie-Jo M.; Matzke, Melissa M.; Jacobs, Jon M.
2011-12-01
Quantification of LC-MS peak intensities assigned during peptide identification in a typical comparative proteomics experiment will deviate from run-to-run of the instrument due to both technical and biological variation. Thus, normalization of peak intensities across a LC-MS proteomics dataset is a fundamental step in pre-processing. However, the downstream analysis of LC-MS proteomics data can be dramatically affected by the normalization method selected . Current normalization procedures for LC-MS proteomics data are presented in the context of normalization values derived from subsets of the full collection of identified peptides. The distribution of these normalization values is unknown a priori. If theymore » are not independent from the biological factors associated with the experiment the normalization process can introduce bias into the data, which will affect downstream statistical biomarker discovery. We present a novel approach to evaluate normalization strategies, where a normalization strategy includes the peptide selection component associated with the derivation of normalization values. Our approach evaluates the effect of normalization on the between-group variance structure in order to identify candidate normalization strategies that improve the structure of the data without introducing bias into the normalized peak intensities.« less
Leinonen, Merja R; Raekallio, Marja R; Vainio, Outi M; Ruohoniemi, Mirja O; O'Brien, Robert T
2011-01-01
Contrast-enhanced ultrasound can be used to quantify tissue perfusion based on region of interest (ROI) analysis. The effect of the location and size of the ROI on the obtained perfusion parameters has been described in phantom, ex vivo and in vivo studies. We assessed the effects of location and size of the ROI on perfusion parameters in the renal cortex of 10 healthy, anesthetized cats using Definity contrast-enhanced ultrasound to estimate the importance of the ROI on quantification of tissue perfusion with contrast-enhanced ultrasound. Three separate sets of ROIs were placed in the renal cortex, varying in location, size or depth. There was a significant inverse association between increased depth or increased size of the ROI and peak intensity (P < 0.05). There was no statistically significant difference in the peak intensity between the ROIs placed in a row in the near field cortex. There was no significant difference in the ROIs with regard to arrival time, time to peak intensity and wash-in rate. When comparing two different ROIs in a patient with focal lesions, such as suspected neoplasia or infarction, the ROIs should always be placed at same depth and be as similar in size as possible.
Mapping the continuous reciprocal space intensity distribution of X-ray serial crystallography.
Yefanov, Oleksandr; Gati, Cornelius; Bourenkov, Gleb; Kirian, Richard A; White, Thomas A; Spence, John C H; Chapman, Henry N; Barty, Anton
2014-07-17
Serial crystallography using X-ray free-electron lasers enables the collection of tens of thousands of measurements from an equal number of individual crystals, each of which can be smaller than 1 µm in size. This manuscript describes an alternative way of handling diffraction data recorded by serial femtosecond crystallography, by mapping the diffracted intensities into three-dimensional reciprocal space rather than integrating each image in two dimensions as in the classical approach. We call this procedure 'three-dimensional merging'. This procedure retains information about asymmetry in Bragg peaks and diffracted intensities between Bragg spots. This intensity distribution can be used to extract reflection intensities for structure determination and opens up novel avenues for post-refinement, while observed intensity between Bragg peaks and peak asymmetry are of potential use in novel direct phasing strategies.
Hansen, Dominique; Rovelo Ruiz, Gustavo; Doherty, Patrick; Iliou, Marie-Christine; Vromen, Tom; Hinton, Sally; Frederix, Ines; Wilhelm, Matthias; Schmid, Jean-Paul; Abreu, Ana; Ambrosetti, Marco; Garcia-Porrero, Esteban; Coninx, Karin; Dendale, Paul
2018-05-01
Background Although disease-specific exercise guidelines for cardiovascular disease (CVD) are widely available, it remains uncertain whether these different exercise guidelines are integrated properly for patients with different CVDs. The aim of this study was to assess the inter-clinician variance in exercise prescription for patients with various CVDs and to compare these prescriptions with recommendations from the EXercise Prescription in Everyday practice and Rehabilitative Training (EXPERT) tool, a digital decision support system for integrated state-of-the-art exercise prescription in CVD. Design The study was a prospective observational survey. Methods Fifty-three CV rehabilitation clinicians from nine European countries were asked to prescribe exercise intensity (based on percentage of peak heart rate (HR peak )), frequency, session duration, programme duration and exercise type (endurance or strength training) for the same five patients. Exercise prescriptions were compared between clinicians, and relationships with clinician characteristics were studied. In addition, these exercise prescriptions were compared with recommendations from the EXPERT tool. Results A large inter-clinician variance was found for prescribed exercise intensity (median (interquartile range (IQR)): 83 (13) % of HR peak ), frequency (median (IQR): 4 (2) days/week), session duration (median (IQR): 45 (18) min/session), programme duration (median (IQR): 12 (18) weeks), total exercise volume (median (IQR): 1215 (1961) peak-effort training hours) and prescription of strength training exercises (prescribed in 78% of all cases). Moreover, clinicians' exercise prescriptions were significantly different from those of the EXPERT tool ( p < 0.001). Conclusions This study reveals significant inter-clinician variance in exercise prescription for patients with different CVDs and disagreement with an integrated state-of-the-art system for exercise prescription, justifying the need for standardization efforts regarding integrated exercise prescription in CV rehabilitation.
Beckers, Paul J; Possemiers, Nadine M; Van Craenenbroeck, Emeline M; Van Berendoncks, An M; Wuyts, Kurt; Vrints, Christiaan J; Conraads, Viviane M
2012-02-01
Exercise training efficiently improves peak oxygen uptake (V˙O2peak) in patients with chronic heart failure. To optimize training-derived benefit, higher exercise intensities are being explored. The correct identification of anaerobic threshold is important to allow safe and effective exercise prescription. During 48 cardiopulmonary exercise tests obtained in patients with chronic heart failure (59.6 ± 11 yrs; left ventricular ejection fraction, 27.9% ± 9%), ventilatory gas analysis findings and lactate measurements were collected. Three technicians independently determined the respiratory compensation point (RCP), the heart rate turning point (HRTP) and the second lactate turning point (LTP2). Thereafter, exercise intensity (target heart rate and workload) was calculated and compared between the three methods applied. Patients had significantly reduced maximal exercise capacity (68% ± 21% of predicted V˙O2peak) and chronotropic incompetence (74% ± 7% of predicted peak heart rate). Heart rate, workload, and V˙O2 at HRTP and at RCP were not different, but at LTP2, these parameters were significantly (P < 0.0001) higher. Mean target heart rate and target workload calculated using the LTP2 were 5% and 12% higher compared with those calculated using HRTP and RCP, respectively. The calculation of target heart rate based on LTP2 was 5% and 10% higher in 12 of 48 (25%) and 6 of 48 (12.5%) patients, respectively, compared with the other two methods. In patients with chronic heart failure, RCP and HRTP, determined during cardiopulmonary exercise tests, precede the occurrence of LTP2. Target heart rates and workloads used to prescribe tailored exercise training in patients with chronic heart failure based on LTP2 are significantly higher than those derived from HRTP and RCP.
Winding, Kamilla M; Munch, Gregers W; Iepsen, Ulrik W; Van Hall, Gerrit; Pedersen, Bente K; Mortensen, Stefan P
2018-05-01
To evaluate whether high-intensity interval training (HIIT) with a lower time commitment can be as effective as endurance training (END) on glycaemic control, physical fitness and body composition in individuals with type 2 diabetes. A total of 29 individuals with type 2 diabetes were allocated to control (CON; no training), END or HIIT groups. Training groups received 3 training sessions per week consisting of either 40 minutes of cycling at 50% of peak workload (END) or 10 1-minute intervals at 95% of peak workload interspersed with 1 minute of active recovery (HIIT). Glycaemic control (HbA1c, oral glucose tolerance test, 3-hour mixed meal tolerance test with double tracer technique and continuous glucose monitoring [CGM]), lipolysis, VO 2 peak and body composition were evaluated before and after 11 weeks of intervention. Exercise training increased VO 2 peak more in the HIIT group (20% ± 20%) compared with the END group (8% ± 9%) despite lower total energy expenditure and time usage during the training sessions. HIIT decreased whole body and android fat mass compared with the CON group. In addition, visceral fat mass, HbA1c, fasting glucose, postprandial glucose, glycaemic variability and HOMA-IR decreased after HIIT. The reduced postprandial glucose in the HIIT group was driven primarily by a lower rate of exogenous glucose appearance. In the CON group, postprandial lipolysis was augmented over the 11-week control period. Despite a ~45% lower training volume, HIIT resulted in similar or even better improvements in physical fitness, body composition and glycemic control compared to END. HIIT therefore appears to be an important time-efficient treatment for individuals with type 2 diabetes. © 2017 John Wiley & Sons Ltd.
Short-Term (<8 Weeks) High-Intensity Interval Training in Diseased Cohorts.
Blackwell, James E M; Doleman, Brett; Herrod, Philip J J; Ricketts, Samuel; Phillips, Bethan E; Lund, Jonathan N; Williams, John P
2018-04-21
Exercise training regimes can lead to improvements in measures of cardiorespiratory fitness (CRF), improved general health, and reduced morbidity and overall mortality risk. High intensity interval training (HIIT) offers a time-efficient approach to improve CRF in healthy individuals, but the relative benefits of HIIT compared to traditional training methods are unknown in across different disease cohorts. This systematic review and meta-analysis compares CRF gains in randomised controlled trials of short-term (<8 weeks) HIIT vs. either no exercise control (CON) or moderate continuous exercise training (MCT) within diseased cohorts. Literature searches of the following databases were performed: MEDLINE, EMBASE, CINAHL, AMED, and PubMed (all from inception to 1st December 2017), with further searches of Clinicaltrials.gov and citations via Google Scholar. Primary outcomes were effect upon CRF variables; VO2peak and Anaerobic Threshold (AT). Thirty-nine studies met the inclusion criteria. HIIT resulted in a clinically significant increase in VO2peak compared with CON (mean difference (MD) 3.32 ml[BULLET OPERATOR]kg[BULLET OPERATOR]min; 95% CI 2.56 to 2.08). Overall HIIT provided added benefit to VO2peak over MCT (MD 0.79 ml[BULLET OPERATOR]kg[BULLET OPERATOR]min; 95% CI 0.20 to 1.39). The benefit of HIIT was most marked in patients with cardiovascular disease when compared to MCT (VO2peak (MD 1.66 ml[BULLET OPERATOR]kg[BULLET OPERATOR]min; 95% CI 0.60 to 2.73); AT (MD 1.61 ml[BULLET OPERATOR]kg[BULLET OPERATOR]min; 95% CI 0.33 to 2.90)). HIIT elicits improvements in objective measures of CRF within 8 weeks in diseased cohorts compared to no intervention. When compared to MCT, HIIT imparts statistically significant additional improvements in measures of CRF, with clinically important additional improvements in VO2peak in cardiovascular patients. Comparative efficacy of HIIT vs MCT combined with an often reduced time commitment may warrant HIIT's promotion as a viable clinical exercise intervention.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.
Demonstrating Optical Aberration Correction With a Mems Micro-Mirror Device
1996-12-01
intensity distributions for a corrected and uncorrected MEMS reflection. The curves have been nor- malized to the peak value of the corrected wave front...demonstration: A = 632.8 mn, f = 7 mm, and L = 203 ym. For the solid curve , s = 0, while the dashed curve shows s = 7r/L, so that the change in phase...specified for Figure 8 (see page 29), so that the figures are directly comparable. The solid curve shows an intensity distribution for 01 = 0 (no
Lafon, Belen; Henin, Simon; Huang, Yu; Friedman, Daniel; Melloni, Lucia; Thesen, Thomas; Doyle, Werner; Buzsáki, György; Devinsky, Orrin; Parra, Lucas C; Liu, Anli
2018-02-28
It has come to our attention that we did not specify whether the stimulation magnitudes we report in this Article are peak amplitudes or peak-to-peak. All references to intensity given in mA in the manuscript refer to peak-to-peak amplitudes, except in Fig. 2, where the model is calibrated to 1 mA peak amplitude, as stated. In the original version of the paper we incorrectly calibrated the computational models to 1 mA peak-to-peak, rather than 1 mA peak amplitude. This means that we divided by a value twice as large as we should have. The correct estimated fields are therefore twice as large as shown in the original Fig. 2 and Supplementary Figure 11. The corrected figures are now properly calibrated to 1 mA peak amplitude. Furthermore, the sentence in the first paragraph of the Results section 'Intensity ranged from 0.5 to 2.5 mA (current density 0.125-0.625 mA mA/cm 2 ), which is stronger than in previous reports', should have read 'Intensity ranged from 0.5 to 2.5 mA peak to peak (peak current density 0.0625-0.3125 mA/cm 2 ), which is stronger than in previous reports.' These errors do not affect any of the Article's conclusions.
High-intensity interval training and athletic performance in Taekwondo athletes.
Monks, Lynne; Seo, Myong-Won; Kim, Hyun-Bae; Jung, Hyun C; Song, Jong K
2017-10-01
The purpose of this study was to determine the effects of high-intensity interval training (HIIT) on athletic performance in Taekwondo athletes. Thirty-three male and female collegiate Taekwondo athletes were randomly divided into a HIIT group (N.=16) or a high-intensity continuous running (HICR) group (N.=17). The HIIT group undertook training of high-intensity sprints interspersed with active rest periods whilst the HICR group participated in high-intensity running for a continuous period. Both groups completed 11 sessions over 4 weeks. Physique, body composition, Wingate anaerobic test and VO2max test were measured. The vertical jump test, agility T-test and sit-ups were used to assess physical fitness. Repeated measures ANCOVAs with sex as a covariate were applied and significant level was set at 0.05. Following 11 sessions of training, significant improvements in anaerobic peak power (P<0.05), relative peak power (P<0.05), and mean power (P<0.05) were observed only in HIIT group compared to HICR group. A greater improvement of aerobic capacity was observed in HIIT group (8.8%) compared to the HICR group (1.7%). In relation to physical fitness, the HIIT group improved in the vertical jump while the HICR group did not change. Both the HIIT and HICR groups showed greater improvements in T-test and sit-ups during the intervention period. This study shows the effectiveness of eleven sessions of HIIT in producing significant improvements in anaerobic capacity relevant to successful Taekwondo competition performance in collegiate Taekwondo athletes. This could inform the future planning of Taekwondo athletes' pre-competition training, specifically the influence of training intensity on anaerobic capacity.
Trombold, Justin R; Christmas, Kevin M; Machin, Daniel R; Kim, Il-Young; Coyle, Edward F
2013-03-15
Acute exercise has been shown to attenuate postprandial plasma triglyceride elevation (PPTG). However, the direct contribution of exercise intensity is less well understood. The purpose of this study was to examine the effects of exercise intensity on PPTG and postprandial fat oxidation. One of three experimental treatments was performed in healthy young men (n = 6): nonexercise control (CON), moderate-intensity exercise (MIE; 50% Vo2peak for 60 min), or isoenergetic high-intensity exercise (HIE; alternating 2 min at 25% and 2 min at 90% Vo2peak). The morning after the exercise, a standardized meal was provided (16 kcal/kg BM, 1.02 g fat/kg, 1.36 g CHO/kg, 0.31 g PRO/kg), and measurements of plasma concentrations of triglyceride (TG), glucose, insulin, and β-hydroxybutyrate were made in the fasted condition and hourly for 6 h postprandial. Indirect calorimetry was used to determine fat oxidation in the fasted condition and 2, 4, and 6 h postprandial. Compared with CON, both MIE and HIE significantly attenuated PPTG [incremental AUC; 75.2 (15.5%), P = 0.033, and 54.9 (13.5%), P = 0.001], with HIE also significantly lower than MIE (P = 0.03). Postprandial fat oxidation was significantly higher in MIE [83.3 (10.6%) of total energy expenditure] and HIE [89.1 (9.8) %total] compared with CON [69.0 (16.1) %total, P = 0.039, and P = 0.018, respectively], with HIE significantly greater than MIE (P = 0.012). We conclude that, despite similar energy expenditure, HIE was more effective than MIE for lowering PPTG and increasing postprandial fat oxidation.
NASA Astrophysics Data System (ADS)
Reichardt, Sven; Wirtz, Ludger
2017-05-01
We present the results of a diagrammatic, fully ab initio calculation of the G peak intensity of graphene. The flexibility and generality of our approach enables us to go beyond the previous analytical calculations in the low-energy regime. We study the laser and Fermi energy dependence of the G peak intensity and analyze the contributions from resonant and nonresonant electronic transitions. In particular, we explicitly demonstrate the importance of quantum interference and nonresonant states for the G peak process. Our method of analysis and computational concept is completely general and can easily be applied to study other materials as well.
Optical chirped beam amplification and propagation
Barty, Christopher P.
2004-10-12
A short pulse laser system uses dispersive optics in a chirped-beam amplification architecture to produce high peak power pulses and high peak intensities without the potential for intensity dependent damage to downstream optical components after amplification.
Hair-bundle proteomes of avian and mammalian inner-ear utricles
Wilmarth, Phillip A.; Krey, Jocelyn F.; Shin, Jung-Bum; Choi, Dongseok; David, Larry L.; Barr-Gillespie, Peter G.
2015-01-01
Examination of multiple proteomics datasets within or between species increases the reliability of protein identification. We report here proteomes of inner-ear hair bundles from three species (chick, mouse, and rat), which were collected on LTQ or LTQ Velos ion-trap mass spectrometers; the constituent proteins were quantified using MS2 intensities, which are the summed intensities of all peptide fragmentation spectra matched to a protein. The data are available via ProteomeXchange with identifiers PXD002410 (chick LTQ), PXD002414 (chick Velos), PXD002415 (mouse Velos), and PXD002416 (rat LTQ). The two chick bundle datasets compared favourably to a third, already-described chick bundle dataset, which was quantified using MS1 peak intensities, the summed intensities of peptides identified by high-resolution mass spectrometry (PXD000104; updated analysis in PXD002445). The mouse bundle dataset described here was comparable to a different mouse bundle dataset quantified using MS1 intensities (PXD002167). These six datasets will be useful for identifying the core proteome of vestibular hair bundles. PMID:26645194
Lanzi, Stefano; Codecasa, Franco; Cornacchia, Mauro; Maestrini, Sabrina; Salvadori, Alberto; Brunani, Amelia; Malatesta, Davide
2014-01-01
This study aimed to compare fat oxidation, hormonal and plasma metabolite kinetics during exercise in lean (L) and obese (O) men. Sixteen L and 16 O men [Body Mass Index (BMI): 22.9 ± 0.3 and 39.0 ± 1.4 kg · m(-2)] performed a submaximal incremental test (Incr) on a cycle-ergometer. Fat oxidation rates (FORs) were determined using indirect calorimetry. A sinusoidal model, including 3 independent variables (dilatation, symmetry, translation), was used to describe fat oxidation kinetics and determine the intensity (Fat(max)) eliciting maximal fat oxidation. Blood samples were drawn for the hormonal and plasma metabolite determination at each step of Incr. FORs (mg · FFM(-1) · min(-1)) were significantly higher from 20 to 30% of peak oxygen uptake (VO2peak) in O than in L and from 65 to 85% VO2peak in L than in O (p ≤ 0.05). FORs were similar in O and in L from 35 to 60% VO2peak. Fat max was 17% significantly lower in O than in L (p<0.01). Fat oxidation kinetics were characterized by similar translation, significantly lower dilatation and left-shift symmetry in O compared with L (p<0.05). During whole exercise, a blunted lipolysis was found in O [lower glycerol/fat mass (FM) in O than in L (p ≤ 0.001)], likely associated with higher insulin concentrations in O than in L (p<0.01). Non-esterified fatty acids (NEFA) were significantly higher in O compared with L (p<0.05). Despite the blunted lipolysis, O presented higher NEFA availability, likely due to larger amounts of FM. Therefore, a lower Fat(max), a left-shifted and less dilated curve and a lower reliance on fat oxidation at high exercise intensities suggest that the difference in the fat oxidation kinetics is likely linked to impaired muscular capacity to oxidize NEFA in O. These results may have important implications for the appropriate exercise intensity prescription in training programs designed to optimize fat oxidation in O.
Numerical modeling of laser-driven ion acceleration from near-critical gas targets
NASA Astrophysics Data System (ADS)
Tatomirescu, Dragos; Vizman, Daniel; d’Humières, Emmanuel
2018-06-01
In the past two decades, laser-accelerated ion sources and their applications have been intensely researched. Recently, it has been shown through experiments that proton beams with characteristics comparable to those obtained with solid targets can be obtained from gaseous targets. By means of particle-in-cell simulations, this paper studies in detail the effects of a near-critical density gradient on ion and electron acceleration after the interaction with ultra high intensity lasers. We can observe that the peak density of the gas jet has a significant influence on the spectrum features. As the gas jet density increases, so does the peak energy of the central quasi-monoenergetic ion bunch due to the increase in laser absorption while at the same time having a broadening effect on the electron angular distribution.
A novel peak detection approach with chemical noise removal using short-time FFT for prOTOF MS data.
Zhang, Shuqin; Wang, Honghui; Zhou, Xiaobo; Hoehn, Gerard T; DeGraba, Thomas J; Gonzales, Denise A; Suffredini, Anthony F; Ching, Wai-Ki; Ng, Michael K; Wong, Stephen T C
2009-08-01
Peak detection is a pivotal first step in biomarker discovery from MS data and can significantly influence the results of downstream data analysis steps. We developed a novel automatic peak detection method for prOTOF MS data, which does not require a priori knowledge of protein masses. Random noise is removed by an undecimated wavelet transform and chemical noise is attenuated by an adaptive short-time discrete Fourier transform. Isotopic peaks corresponding to a single protein are combined by extracting an envelope over them. Depending on the S/N, the desired peaks in each individual spectrum are detected and those with the highest intensity among their peak clusters are recorded. The common peaks among all the spectra are identified by choosing an appropriate cut-off threshold in the complete linkage hierarchical clustering. To remove the 1 Da shifting of the peaks, the peak corresponding to the same protein is determined as the detected peak with the largest number among its neighborhood. We validated this method using a data set of serial peptide and protein calibration standards. Compared with MoverZ program, our new method detects more peaks and significantly enhances S/N of the peak after the chemical noise removal. We then successfully applied this method to a data set from prOTOF MS spectra of albumin and albumin-bound proteins from serum samples of 59 patients with carotid artery disease compared to vascular disease-free patients to detect peaks with S/N> or =2. Our method is easily implemented and is highly effective to define peaks that will be used for disease classification or to highlight potential biomarkers.
Hwang, Chueh-Lung; Yoo, Jeung-Ki; Kim, Han-Kyul; Hwang, Moon-Hyon; Handberg, Eileen M.; Petersen, John W.; Christou, Demetra D.
2016-01-01
Aging is associated with decreased aerobic fitness and cardiac remodeling leading to increased risk for cardiovascular disease. High-intensity interval training (HIIT) on the treadmill has been reported to be more effective in ameliorating these risk factors compared with moderate-intensity continuous training (MICT) in patients with cardiometabolic disease. In older adults, however, weight-bearing activities are frequently limited due to musculoskeletal and balance problems. The purpose of this study was to examine the feasibility and safety of non-weight-bearing all-extremity HIIT in older adults. In addition, we tested the hypothesis that all-extremity HIIT will be more effective in improving aerobic fitness, cardiac function, and metabolic risk factors compared with all-extremity MICT. Fifty-one healthy sedentary older adults (age: 65±1 years) were randomized to HIIT (n=17), MICT (n=18) or non-exercise control (CONT; n=16). HIIT (4×4 minutes 90% of peak heart rate; HRpeak) and isocaloric MICT (70% of HRpeak) were performed on a non-weight-bearing all-extremity ergometer, 4x/week for 8 weeks under supervision. All-extremity HIIT was feasible in older adults and resulted in no adverse events. Aerobic fitness (peak oxygen consumption; VO2peak) and ejection fraction (echocardiography) improved by 11% (P<0.0001) and 4% (P=0.001) respectively in HIIT, while no changes were observed in MICT and CONT (P≥0.1). Greater improvements in ejection fraction were associated with greater improvements in VO2peak (r=0.57; P<0.0001). Insulin resistance (homeostatic model assessment) decreased only in HIIT by 26% (P=0.016). Diastolic function, body composition, glucose and lipids were unaffected (P≥0.1). In conclusion, all-extremity HIIT is feasible and safe in older adults. HIIT, but not MICT, improved aerobic fitness, ejection fraction, and insulin resistance. PMID:27346646
Hwang, Chueh-Lung; Yoo, Jeung-Ki; Kim, Han-Kyul; Hwang, Moon-Hyon; Handberg, Eileen M; Petersen, John W; Christou, Demetra D
2016-09-01
Aging is associated with decreased aerobic fitness and cardiac remodeling leading to increased risk for cardiovascular disease. High-intensity interval training (HIIT) on the treadmill has been reported to be more effective in ameliorating these risk factors compared with moderate-intensity continuous training (MICT) in patients with cardiometabolic disease. In older adults, however, weight-bearing activities are frequently limited due to musculoskeletal and balance problems. The purpose of this study was to examine the feasibility and safety of non-weight-bearing all-extremity HIIT in older adults. In addition, we tested the hypothesis that all-extremity HIIT will be more effective in improving aerobic fitness, cardiac function, and metabolic risk factors compared with all-extremity MICT. Fifty-one healthy sedentary older adults (age: 65±1years) were randomized to HIIT (n=17), MICT (n=18) or non-exercise control (CONT; n=16). HIIT (4×4min 90% of peak heart rate; HRpeak) and isocaloric MICT (70% of HRpeak) were performed on a non-weight-bearing all-extremity ergometer, 4×/week for 8weeks under supervision. All-extremity HIIT was feasible in older adults and resulted in no adverse events. Aerobic fitness (peak oxygen consumption; VO2peak) and ejection fraction (echocardiography) improved by 11% (P<0.0001) and 4% (P=0.001), respectively in HIIT, while no changes were observed in MICT and CONT (P≥0.1). Greater improvements in ejection fraction were associated with greater improvements in VO2peak (r=0.57; P<0.0001). Insulin resistance (homeostatic model assessment) decreased only in HIIT by 26% (P=0.016). Diastolic function, body composition, glucose and lipids were unaffected (P≥0.1). In conclusion, all-extremity HIIT is feasible and safe in older adults. HIIT, but not MICT, improved aerobic fitness, ejection fraction, and insulin resistance. Copyright © 2016 Elsevier Inc. All rights reserved.
Comparison of injury epidemiology between the Wenchuan and Lushan earthquakes in Sichuan, China.
Hu, Yang; Zheng, Xi; Yuan, Yong; Pu, Qiang; Liu, Lunxu; Zhao, Yongfan
2014-12-01
We aimed to compare injury characteristics and the timing of admissions and surgeries in the Wenchuan earthquake in 2008 and the Lushan earthquake in 2013. We retrospectively compared the admission and operating times and injury profiles of patients admitted to our medical center during both earthquakes. We also explored the relationship between seismic intensity and injury type. The time from earthquake onset to the peak in patient admissions and surgeries differed between the 2 earthquakes. In the Wenchuan earthquake, injuries due to being struck by objects or being buried were more frequent than other types of injuries, and more patients suffered injuries of the extremities than thoracic injuries or brain trauma. In the Lushan earthquake, falls were the most common injury, and more patients suffered thoracic trauma or brain injuries. The types of injury seemed to vary with seismic intensity, whereas the anatomical location of the injury did not. Greater seismic intensity of an earthquake is associated with longer delay between the event and the peak in patient admissions and surgeries, higher frequencies of injuries due to being struck or buried, and lower frequencies of injuries due to falls and injuries to the chest and brain. These insights may prove useful for planning rescue interventions in trauma centers near the epicenter.
Stöcker, F; Von Oldershausen, C; Paternoster, F K; Schulz, T; Oberhoffer, R
2017-07-01
Increased local blood supply is thought to be one of the mechanisms underlying oxidative adaptations to interval training regimes. The relationship of exercise intensity with local blood supply and oxygen availability has not been sufficiently evaluated yet. The aim of this study was to examine the effect of six different intensities (40-90% peak oxygen uptake, VO 2peak ) on relative changes in oxygenated, deoxygenated and total haemoglobin (ΔO 2 Hb, ΔHHb, ΔTHb) concentration after exercise as well as end-exercise ΔHHb/ΔVO 2 as a marker for microvascular O 2 distribution. Seventeen male subjects performed an experimental protocol consisting of 3 min cycling bouts at each exercise intensity in randomized order, separated by 5 min rests. ΔO 2 Hb and ΔHHb were monitored with near-infrared spectroscopy of the vastus lateralis muscle, and VO 2 was assessed. ΔHHb/ΔVO 2 increased significantly from 40% to 60% VO 2 peak and decreased from 60% to 90% VO 2 peak. Post-exercise ΔTHb and ΔO 2 Hb showed an overshoot in relation to pre-exercise values, which was equal after 40-60% VO 2peak and rose significantly thereafter. A plateau was reached following exercise at ≥80% VO 2peak . The results suggest that there is an increasing mismatch of local O 2 delivery and utilization during exercise up to 60% VO 2peak . This insufficient local O 2 distribution is progressively improved above that intensity. Further, exercise intensities of ≥80% VO 2peak induce highest local post-exercise O 2 availability. These effects are likely due to improved microvascular perfusion by enhanced vasodilation, which could be mediated by higher lactate production and the accompanying acidosis. © 2015 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.
Variation in light intensity with height and time from subsequent lightning return strokes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jordan, D.M.; Uman, M.A.
1983-08-20
Relative light intensity has been measured photographically as a function of height and time for seven subsequent return strokes in two lightning flashes at ranges of 7.8 and 8.7 km. The film used was Kodak 5474 Shellburst, which has a roughly constant spectral response between 300 and 670 nm. The time resolution was about 1.0 ..mu..s, and the spatial resolution was about 4 m. The observed light signals consisted of a fast rise to peak, followed by a slower decrease to a relatively constant value. The amplitude of the initial light peak decreases exponentially with height with a decay constantmore » of about 0.6 to 0.8 km. The 20% to 80% rise time of the initial light signal is between 1 and 4 ..mu..s near ground and increases by an additional 1 to 2 ..mu..s by the time the return stroke reaches the cloud base, a height between 1 and 2 km. The light intensity 30 ..mu..s after the initial peak is relatively constant with height and has an amplitude that is 15% to 30% of the initial peak near the ground and 50% to 100% of the initial peak at cloud base. The logarithm of the peak light intensity near the ground is roughly proportional to the initial peak electric field intensity, and this in turn implies that the current decrease with height may be much slower than the light decrease. The absolute light intensity has been estimated by integrating the photographic signals from individual channel segments to simulate the calibrated all-sky photoelectric data of Guo and Krider (1982). Using this method, the authors find that the mean peak radiance near the ground is 8.3 x 10/sup 5/ W/m, with a total range from 1.4 x 10/sup 5/ to 3.8 x 10/sup 6/ W/m. 16 references, 11 figures.« less
Integrated Freestanding Two-dimensional Transition Metal Dichalcogenides.
Jeong, Hyun; Oh, Hye Min; Gokarna, Anisha; Kim, Hyun; Yun, Seok Joon; Han, Gang Hee; Jeong, Mun Seok; Lee, Young Hee; Lerondel, Gilles
2017-05-01
This paper reports on the integration of freestanding transition metal dichalcogenides (TMDs). Monolayer (1-L) MoS 2 , WS 2 , and WSe 2 as representative TMDs are transferred on ZnO nanorods (NRs), used here as nanostructured substrates. The photoluminescence (PL) spectra of 1-L TMDs on NRs show a giant PL intensity enhancement, compared with those of 1-L TMDs on SiO 2 . The strong increases in Raman and PL intensities, along with the characteristic peak shifts, confirm the absence of stress in the TMDs on NRs. In depth analysis of the PL emission also reveals that the ratio between the exciton and trion peak intensity is almost not modified after transfer. The latter shows that the effect of charge transfer between the 1-L TMDs and ZnO NRs is here negligible. Furthermore, confocal PL and Raman spectroscopy reveal a fairly consistent distribution of PL and Raman intensities. These observations are in agreement with a very limited points contact between the support and the 1-L TMDs. The entire process reported here is scalable and may pave the way for the development of very efficient ultrathin optoelectronics. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Measurement and Modeling of Acoustic Fields in a Gel Phantom at High Intensities
NASA Astrophysics Data System (ADS)
Canney, Michael S.; Bailey, Michael R.; Khokhlova, Vera A.; Crum, Lawrence A.
2006-05-01
The goal of this work was to compare measured and numerically predicted HIFU pressure waveforms in water and a tissue-mimicking phantom. Waveforms were measured at the focus of a 2-MHz HIFU transducer with a fiber optic hydrophone. The transducer was operated with acoustic powers ranging from 2W to 300W. A KZK-type equation was used for modeling the experimental conditions. Strongly asymmetric nonlinear waves with peak positive pressure up to 80 MPa and peak negative pressure up to 20 MPa were measured in water, while waves up to 50 MPa peak positive pressure and 15 MPa peak negative pressure were measured in tissue phantoms. The values of peak negative pressure corresponded well with numerical simulations and were significantly smaller than predicted by linear extrapolation from low-level measurements. The values of peak positive pressures differed only at high levels of excitation where bandwidth limitations of the hydrophone failed to fully capture the predicted sharp shock fronts.
Kirkham, Amy A; Pauhl, Katherine E; Elliott, Robyn M; Scott, Jen A; Doria, Silvana C; Davidson, Hanan K; Neil-Sztramko, Sarah E; Campbell, Kristin L; Camp, Pat G
2015-01-01
To determine the utility of equations that use the 6-minute walk test (6MWT) results to estimate peak oxygen uptake ((Equation is included in full-text article.)o2) and peak work rate with chronic obstructive pulmonary disease (COPD) patients in a clinical setting. This study included a systematic review to identify published equations estimating peak (Equation is included in full-text article.)o2 and peak work rate in watts in COPD patients and a retrospective chart review of data from a hospital-based pulmonary rehabilitation program. The following variables were abstracted from the records of 42 consecutively enrolled COPD patients: measured peak (Equation is included in full-text article.)o2 and peak work rate achieved during a cycle ergometer cardiopulmonary exercise test, 6MWT distance, age, sex, weight, height, forced expiratory volume in 1 second, forced vital capacity, and lung diffusion capacity. Estimated peak (Equation is included in full-text article.)o2 and peak work rate were estimated from 6MWT distance using published equations. The error associated with using estimated peak (Equation is included in full-text article.)o2 or peak work to prescribe aerobic exercise intensities of 60% and 80% was calculated. Eleven equations from 6 studies were identified. Agreement between estimated and measured values was poor to moderate (intraclass correlation coefficients = 0.11-0.63). The error associated with using estimated peak (Equation is included in full-text article.)o2 or peak work rate to prescribe exercise intensities of 60% and 80% of measured values ranged from mean differences of 12 to 35 and 16 to 47 percentage points, respectively. There is poor to moderate agreement between measured peak (Equation is included in full-text article.)o2 and peak work rate and estimations from equations that use 6MWT distance, and the use of the estimated values for prescription of aerobic exercise intensity would result in large error. Equations estimating peak (Equation is included in full-text article.)o2 and peak work rate are of low utility for prescribing exercise intensity in pulmonary rehabilitation programs.
High-intensity cycle interval training improves cycling and running performance in triathletes.
Etxebarria, Naroa; Anson, Judith M; Pyne, David B; Ferguson, Richard A
2014-01-01
Effective cycle training for triathlon is a challenge for coaches. We compared the effects of two variants of cycle high-intensity interval training (HIT) on triathlon-specific cycling and running. Fourteen moderately-trained male triathletes ([Formula: see text]O2peak 58.7 ± 8.1 mL kg(-1) min(-1); mean ± SD) completed on separate occasions a maximal incremental test ([Formula: see text]O2peak and maximal aerobic power), 16 × 20 s cycle sprints and a 1-h triathlon-specific cycle followed immediately by a 5 km run time trial. Participants were then pair-matched and assigned randomly to either a long high-intensity interval training (LONG) (6-8 × 5 min efforts) or short high-intensity interval training (SHORT) (9-11 × 10, 20 and 40 s efforts) HIT cycle training intervention. Six training sessions were completed over 3 weeks before participants repeated the baseline testing. Both groups had an ∼7% increase in [Formula: see text]O2peak (SHORT 7.3%, ±4.6%; mean, ±90% confidence limits; LONG 7.5%, ±1.7%). There was a moderate improvement in mean power for both the SHORT (10.3%, ±4.4%) and LONG (10.7%, ±6.8%) groups during the last eight 20-s sprints. There was a small to moderate decrease in heart rate, blood lactate and perceived exertion in both groups during the 1-h triathlon-specific cycling but only the LONG group had a substantial decrease in the subsequent 5-km run time (64, ±59 s). Moderately-trained triathletes should use both short and long high-intensity intervals to improve cycling physiology and performance. Longer 5-min intervals on the bike are more likely to benefit 5 km running performance.
The generation of amplified spontaneous emission in high-power CPA laser systems.
Keppler, Sebastian; Sävert, Alexander; Körner, Jörg; Hornung, Marco; Liebetrau, Hartmut; Hein, Joachim; Kaluza, Malte Christoph
2016-03-01
An analytical model is presented describing the temporal intensity contrast determined by amplified spontaneous emission in high-intensity laser systems which are based on the principle of chirped pulse amplification. The model describes both the generation and the amplification of the amplified spontaneous emission for each type of laser amplifier. This model is applied to different solid state laser materials which can support the amplification of pulse durations ≤350 fs . The results are compared to intensity and fluence thresholds, e.g. determined by damage thresholds of a certain target material to be used in high-intensity applications. This allows determining if additional means for contrast improvement, e.g. plasma mirrors, are required for a certain type of laser system and application. Using this model, the requirements for an optimized high-contrast front-end design are derived regarding the necessary contrast improvement and the amplified "clean" output energy for a desired focussed peak intensity. Finally, the model is compared to measurements at three different high-intensity laser systems based on Ti:Sapphire and Yb:glass. These measurements show an excellent agreement with the model.
Twitch analysis as an approach to motor unit activation during electrical stimulation.
Heyters, M; Carpentier, A; Duchateau, J; Hainaut, K
1994-12-01
The mechanical twitch in response to increasing electrical stimulus intensity, delivered both over the motor point and motor nerve, was recorded in the first dorsal interosseous (FDI) and the adductor pollicis (AP), and only over the motor point in the soleus (Sol), lateral (LG), and medial (MG) gastrocnemius muscles of human subjects. The relationship between intensity of electrical stimulation (ES) and twitch torque showed a positive linear regression in all muscles. In the FDI and AP the relationship was not significantly different when ES was applied at the motor point or over the motor nerve. At small intensities of activation, ES induced larger twitch torques in the MG and LG, which contain a roughly equal proportion of slow and fast motor units (MUs) compared to the Sol, which is composed mainly of slow type fibres. Moreover, the relationship between ES intensity and twitch time-to-peak is best fitted in all muscles by a power curve that shows a greater twitch time-to-peak range in its initial part for muscles containing a larger proportion of fast MUs (LG, MG) than for muscles mainly composed of slow MUs (Sol). In conclusion, these results induced by ES at the motor point and/or over the motor nerve confirm the concept of a reversed sequence of MU activation, as compared to voluntary contractions, and document this viewpoint in muscles of different function and composition. The reversed sequence of MU activation is more clearly evident during motor point ES.
Alternatives to Pyrotechnic Distress Signals; Supplemental Report
2015-08-01
distribution of an incandescent lamp as compared to a specific white LED . ...................... 3 Figure 3. Spectral distribution of a “cool” white LED ...of common lamps2. Figure 2 shows the spectral distribution of an incandescent lamp as compared to a “cool” white LED . Note the LED peak intensity in...project effort that developed a specification for a light-emitting diode ( LED ) signal characteristic as an alternative to pyrotechnic, maritime
Salve, P R; Lohkare, H; Gobre, T; Bodhe, G; Krupadam, R J; Ramteke, D S; Wate, S R
2012-02-01
The fluorescence excitation-emission matrix of Chromophoric dissolved organic matter (CDOM) samples from rainwater collected at Rameswaram, Tamilnadu, India are analysed. Total five peaks were observed for humic/marine and protein likes substances respectively. The peak A and C intensities varies form 1.98 ± 0.28 and 0.97 ± 0.11 QSU respectively represents humic like substances. The peak B and T intensities varies from 3.94 ± 0.75 and 7.42 ± 1.43 QSU showed association of protein like substances whereas peak M intensities varies from 1.92 ± 0.37 QSU indicates marine contribution. Among the fluorophores, the following sequence were observed as T > B > A > M > C which indicates dominance of Tryptophan like substances in rainwater. The average peak T/C ratios was observed as 7.88 ± 2.2 indicates microbial contamination by Tryptophan-like substances with the high biological activity and low volatility.
Messinger, Terence
2003-01-01
During storms when rainfall intensity exceeded about 1 inch per hour, peak unit runoff from the Unnamed Tributary (surface-mined and filled) Watershed exceeded peak unit runoff from the Spring Branch (unmined) Watershed in the Ballard Fork Watershed in southern West Virginia. During most storms, those with intensity less than about 1 inch per hour, peak unit (area-normalized) flows were greater from the Spring Branch Watershed than the Unnamed Tributary Watershed. One storm that produced less than an inch of rain before flow from the previous storm had receded caused peak unit flow from the Unnamed Tributary Watershed to exceed peak unit flow from the Spring Branch Watershed. Peak unit flow was usually similar in Spring Branch and Ballard Fork. Peak unit flows are expected to decrease with increasing watershed size in homogeneous watersheds; drainage area and proportion of the three watersheds covered by valley fills are 0.19 square mile (mi?) and 44 percent for the Unnamed Tributary Watershed, 0.53 mi? and 0 percent for the Spring Branch Watershed, and 2.12 mi? and 12 percent for the Ballard Fork Watershed. Following all storms with sufficient rainfall intensity, about 0.25 inches per hour, the storm hydrograph from the Unnamed Tributary Watershed showed a double peak, as a sharp initial rise was followed by a decrease in flow and then a delayed secondary peak of water that had apparently flowed through the valley fill. Hortonian (excess overland) flow may be important in the Unnamed Tributary Watershed during intense storms, and may cause the initial peak on the rising arm of storm hydrographs; the water composing the initial peaks may be conveyed by drainage structures on the mine. Ballard Fork and Spring Branch had hydrographs with single peaks, typical of elsewhere in West Virginia. During all storms with 1-hour rainfall greater than 0.75 inches or 24-hour rainfall greater than 1.75 inches during which all stream gages recorded a complete record, the Unnamed Tributary yielded the most total unit flow. In three selected major storms, total unit flow from the Unnamed Tributary during recessions exceeded storm flow, and its total unit flow was greatest among the streams during all three recessions. Runoff patterns from the mined watershed are influenced by the compaction of soils on the mine, the apparent low maximum rate of infiltration into the valley fill compared to that in the unmined, forested watershed, storage of water in the valley fill, and the absence of interception from trees and leaf litter. No storms during this study produced 1-hour or 24-hour rainfall in excess of the 5-year return period, and streamflow during this study never exceeded a magnitude equivalent to the 1.5-year return period; relative peak unit flow among the three streams in this study could be different in larger storms. Rainfall-runoff relations on altered landscapes are site-specific, and aspects of mining and reclamation practice that affect storm response may vary among mines.
FTIR spectroscopy of multiwalled carbon nanotubes: a simple approach to study the nitrogen doping.
Misra, Abha; Tyagi, Pawan K; Rai, Padmnabh; Misra, D S
2007-06-01
The nitrogen doped multiwalled carbon nanotubes (MWNTs) were synthesized by microwave plasma chemical vapor deposition (MPCVD) technique. In this paper, we report the results of FTIR, Raman, and TGA studies to confirm the presence of N-doping inside carbon nanotubes. Fourier transform infrared (FTIR) studies were carried out in the range 400-4000 cm(-1) to study the attachment of nitrogen impurities on carbon nanotubes. FTIR spectra of the virgin sample of MWNTs show dominant peaks which are corresponding to Si-O, C-N, N-CH3, CNT, C-O, and C-Hx, respectively. The Si-O peak has its origin in silicon substrate whereas the other peaks are due to the precursor gases present in the gas mixture. The peaks are sharp and highly intense showing the chemisorption nature of the dipole bond. The intensity of the peaks due to N-CH3, C-N, and C-H reduces after annealing. It is interesting to note that these peaks vanish on annealing at high temperature (900 degrees C). The presence of C-N peak may imply the doping of the MWNTs with N in substitution mode. The position of this intense peak is in agreement with the reported peak in carbon nitride samples prepared by plasma CVD process, since the Raman modes are also expected to be delocalized over both carbon and nitrogen sites it was found that the intensity ratio of the D and G peaks, I(D)/I(G), varies as a function of ammonia concentration. The TGA measurements, carried out under argon flow, show that the dominant weight loss of the sample occurs in the temperature range 400-600 degrees C corresponding to the removal of the impurities and amorphous carbon.
Hara, Risa; Ishigaki, Mika; Kitahama, Yasutaka; Ozaki, Yukihiro; Genkawa, Takuma
2018-02-15
In this study, a lycopene-content-based discriminant analysis was performed using a portable near-infrared-excited Raman spectrometer. In the vegetable-juice Raman spectra, the peak intensity of the lycopene band increased with increasing lycopene concentration, but scattering decreased the repeatability of the peak intensity. Consequently, developing a lycopene-concentration regression model using peak intensity is not straightforward. Therefore, a new method known as the product of mean intensity ratio (PMIR) analysis was developed to rapidly identify lycopene-rich samples on-site. In the PMIR analysis, Raman spectra are measured with short exposure times, confirming only the peaks of carotenoids with high concentrations, and thus the lycopene concentrations of vegetable juice samples could be determined successfully. Exposure times of 20ms and 100ms could detect lycopene concentrations of ≥5mg/100g and ≥2mg/100g with 93.2% and 97.7% accuracy, respectively; thus, lycopene-content-based discriminant analysis using the PMIR and a portable Raman spectrometer is feasible. Copyright © 2017 Elsevier Ltd. All rights reserved.
Satoh, Takafumi; Kishi, Shintaro; Nagashima, Hisayuki; Tachikawa, Masumi; Kanamori-Kataoka, Mieko; Nakagawa, Takao; Kitagawa, Nobuyoshi; Tokita, Kenichi; Yamamoto, Soichiro; Seto, Yasuo
2015-03-20
The ion mobility behavior of nineteen chemical warfare agents (7 nerve gases, 5 blister agents, 2 lachrymators, 2 blood agents, 3 choking agents) and related compounds including simulants (8 agents) and organic solvents (39) was comparably investigated by the ion mobility spectrometry instrument utilizing weak electric field linear drift tube with corona discharge ionization, ammonia doping, purified inner air drift flow circulation operated at ambient temperature and pressure. Three alkyl methylphosphonofluoridates, tabun, and four organophosphorus simulants gave the intense characteristic positive monomer-derived ion peaks and small dimer-derived ion peaks, and the later ion peaks were increased with the vapor concentrations. VX, RVX and tabun gave both characteristic positive monomer-derived ions and degradation product ions. Nitrogen mustards gave the intense characteristic positive ion peaks, and in addition distinctive negative ion peak appeared from HN3. Mustard gas, lewisite 1, o-chlorobenzylidenemalononitrile and 2-mercaptoethanol gave the characteristic negative ion peaks. Methylphosphonyl difluoride, 2-chloroacetophenone and 1,4-thioxane gave the characteristic ion peaks both in the positive and negative ion mode. 2-Chloroethylethylsulfide and allylisothiocyanate gave weak ion peaks. The marker ion peaks derived from two blood agents and three choking agents were very close to the reactant ion peak in negative ion mode and the respective reduced ion mobility was fluctuated. The reduced ion mobility of the CWA monomer-derived peaks were positively correlated with molecular masses among structurally similar agents such as G-type nerve gases and organophosphorus simulants; V-type nerve gases and nitrogen mustards. The slope values of the calibration plots of the peak heights of the characteristic marker ions versus the vapor concentrations are related to the detection sensitivity, and within chemical warfare agents examined the slope values for sarin, soman, tabun and nitrogen mustards were higher. Some CWA simulants and organic solvents gave the ion peaks eluting at the similar positions of the CWAs, resulting in false positive alarms. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Cilia, M. G.; Baker, L. M.
2015-12-01
We determine empirical relationships between instrumental peak ground motions and observed intensities for two great Chilean subduction earthquakes: the 2010 Mw8.8 Maule earthquake and the 2014 Mw8.2 Iquique earthquake. Both occurred immediately offshore on the primary plate boundary interface between the Nazca and South America plates. They are among the largest earthquakes to be instrumentally recorded; the 2010 Maule event is the second largest earthquake to produce strong motion recordings. Ground motion to intensity conversion equations (GMICEs) are used to reconstruct the distribution of shaking for historical earthquakes by using intensities estimated from contemporary accounts. Most great (M>8) earthquakes, like these, occur within subduction zones, yet few GMICEs exist for subduction earthquakes. It is unclear whether GMICEs developed for active crustal regions, such as California, can be scaled up to the large M of subduction zone events, or if new data sets must be analyzed to develop separate subduction GMICEs. To address this question, we pair instrumental peak ground motions, both acceleration (PGA) and velocity (PGV), with intensities derived from onsite surveys of earthquake damage made in the weeks after the events and internet-derived felt reports. We fit a linear predictive equation between the geometric mean of the maximum PGA or PGV of the two horizontal components and intensity, using linear least squares. We use a weighting scheme to express the uncertainty of the pairings based on a station's proximity to the nearest intensity observation. The intensity data derived from the onsite surveys is a complete, high-quality investigation of the earthquake damage. We perform the computations using both the survey data and community decimal intensities (CDI) calculated from felt reports volunteered by citizens (USGS "Did You Feel It", DYFI) and compare the results. We compare the GMICEs we developed to the most widely used GMICEs from California and central US earthquakes, and global earthquakes. Existing GMICEs consistently over-predict intensity for these two subduction events. This may be a regional difference, or a magnitude-dependent effect. Currently, however, there is not enough data from these great subduction earthquakes to prefer one interpretation over the other.
Hu, Kaifeng; Westler, William M; Markley, John L
2011-02-16
Quantitative one-dimensional (1D) (1)H NMR spectroscopy is a useful tool for determining metabolite concentrations because of the direct proportionality of signal intensity to the quantity of analyte. However, severe signal overlap in 1D (1)H NMR spectra of complex metabolite mixtures hinders accurate quantification. Extension of 1D (1)H to 2D (1)H-(13)C HSQC leads to the dispersion of peaks along the (13)C dimension and greatly alleviates peak overlapping. Although peaks are better resolved in 2D (1)H-(13)C HSQC than in 1D (1)H NMR spectra, the simple proportionality of cross peaks to the quantity of individual metabolites is lost by resonance-specific signal attenuation during the coherence transfer periods. As a result, peaks for individual metabolites usually are quantified by reference to calibration data collected from samples of known concentration. We show here that data from a series of HSQC spectra acquired with incremented repetition times (the time between the end of the first (1)H excitation pulse to the beginning of data acquisition) can be extrapolated back to zero time to yield a time-zero 2D (1)H-(13)C HSQC spectrum (HSQC(0)) in which signal intensities are proportional to concentrations of individual metabolites. Relative concentrations determined from cross peak intensities can be converted to absolute concentrations by reference to an internal standard of known concentration. Clustering of the HSQC(0) cross peaks by their normalized intensities identifies those corresponding to metabolites present at a given concentration, and this information can assist in assigning these peaks to specific compounds. The concentration measurement for an individual metabolite can be improved by averaging the intensities of multiple, nonoverlapping cross peaks assigned to that metabolite.
Smiles, William J; Conceição, Miguel S; Telles, Guilherme D; Chacon-Mikahil, Mara P T; Cavaglieri, Cláudia R; Vechin, Felipe C; Libardi, Cleiton A; Hawley, John A; Camera, Donny M
2017-02-01
Autophagy is an intracellular degradative system sensitive to hypoxia and exercise-induced perturbations to cellular bioenergetics. We determined the effects of low-intensity endurance-based exercise performed with blood-flow restriction (BFR) on cell signaling adaptive responses regulating autophagy and substrate metabolism in human skeletal muscle. In a randomized cross-over design, nine young, healthy but physically inactive males completed three experimental trials separated by 1 week of recovery consisting of either a resistance exercise bout (REX: 4 × 10 leg press repetitions, 70% 1-RM), endurance exercise (END: 30 min cycling, 70% VO 2peak ), or low-intensity cycling with BFR (15 min, 40% VO 2peak ). A resting muscle biopsy was obtained from the vastus lateralis 2 weeks prior to the first exercise trial and 3 h after each exercise bout. END increased ULK1 Ser757 phosphorylation above rest and BFR (~37 to 51%, P < 0.05). Following REX, there were significant elevations compared to rest (~348%) and BFR (~973%) for p38γ MAPK Thr180/Tyr182 phosphorylation (P < 0.05). Parkin content was lower following BFR cycling compared to REX (~20%, P < 0.05). There were no exercise-induced changes in select markers of autophagy following BFR. Genes implicated in substrate metabolism (HK2 and PDK4) were increased above rest (~143 to 338%) and BFR cycling (~212 to 517%) with END (P < 0.001). A single bout of low-intensity cycling with BFR is insufficient to induce intracellular "stress" responses (e.g., high rates of substrate turnover and local hypoxia) necessary to activate skeletal muscle autophagy signaling.
Rynders, Corey A.; Weltman, Judy Y.; Jiang, Boyi; Breton, Marc; Patrie, James; Barrett, Eugene J.
2014-01-01
Background: A single bout of exercise improves postprandial glycemia and insulin sensitivity in prediabetic patients; however, the impact of exercise intensity is not well understood. The present study compared the effects of acute isocaloric moderate (MIE) and high-intensity (HIE) exercise on glucose disposal and insulin sensitivity in prediabetic adults. Methods: Subjects (n = 18; age 49 ± 14 y; fasting glucose 105 ± 11 mg/dL; 2 h glucose 170 ± 32 mg/dL) completed a peak O2 consumption/lactate threshold (LT) protocol plus three randomly assigned conditions: 1) control, 1 hour of seated rest, 2) MIE (at LT), and 3) HIE (75% of difference between LT and peak O2 consumption). One hour after exercise, subjects received an oral glucose tolerance test (OGTT). Plasma glucose, insulin, and C-peptide concentrations were sampled at 5- to 10-minute intervals at baseline, during exercise, after exercise, and for 3 hours after glucose ingestion. Total, early-phase, and late-phase area under the glucose and insulin response curves were compared between conditions. Indices of insulin sensitivity (SI) were derived from OGTT data using the oral minimal model. Results: Compared with control, SI improved by 51% (P = .02) and 85% (P < .001) on the MIE and HIE days, respectively. No differences in SI were observed between the exercise conditions (P = .62). Improvements in SI corresponded to significant reductions in the glucose, insulin, and C-peptide area under the curve values during the late phase of the OGTT after HIE (P < .05), with only a trend for reductions after MIE. Conclusion: These results suggest that in prediabetic adults, acute exercise has an immediate and intensity-dependent effect on improving postprandial glycemia and insulin sensitivity. PMID:24243632
Weston, Kassia S; Wisløff, Ulrik; Coombes, Jeff S
2014-08-01
Cardiorespiratory fitness (CRF) is a strong determinant of morbidity and mortality. In athletes and the general population, it is established that high-intensity interval training (HIIT) is superior to moderate-intensity continuous training (MICT) in improving CRF. This is a systematic review and meta-analysis to quantify the efficacy and safety of HIIT compared to MICT in individuals with chronic cardiometabolic lifestyle diseases. The included studies were required to have a population sample of chronic disease, where poor lifestyle is considered as a main contributor to the disease. The procedural quality of the studies was assessed by use of a modified Physiotherapy Evidence Base Database (PEDro) scale. A meta-analysis compared the mean difference (MD) of preintervention versus postintervention CRF (VO2peak) between HIIT and MICT. 10 studies with 273 patients were included in the meta-analysis. Participants had coronary artery disease, heart failure, hypertension, metabolic syndrome and obesity. There was a significantly higher increase in the VO2peak after HIIT compared to MICT (MD 3.03 mL/kg/min, 95% CI 2.00 to 4.07), equivalent to 9.1%. HIIT significantly increases CRF by almost double that of MICT in patients with lifestyle-induced chronic diseases. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Shimizu, Muneshige; Miyagawa, Ken; Iwashita, Soh; Noda, Tsuneyuki; Hamada, Koichiro; Genno, Hirokazu; Nose, Hiroshi
2012-03-01
We compared relative exercise intensity and active energy expenditure (AEE) on trail walking in the mountains, with those of daily exercise training, and whether branched-chain amino acid (BCAA) and arginine supplementation attenuated the release of markers indicating muscle damage and declines in physical performance. Twenty-one subjects (~63 years) were divided into two groups: amino acid (AA, 51 g of amino acids and 40 g of carbohydrate, male/female = 6/4) or placebo (PL, 91 g of carbohydrate, male/female = 6/5) supplementation during 2 days of trail walking in the mountains. We measured heart rate (HR), AEE, fatigue sensation, water and food intake, and sweat loss during walking. In addition, we measured peak aerobic capacity [Formula: see text] and heart rate (HR(peak)) with graded-intensity walking, vertical jumping height (VJ) before and after walking. We found that average HR and AEE during uphill walking were ~100% HR(peak) and ~60% [Formula: see text], while they were ~80 and ~20% during downhill walking, respectively. Moreover, average total AEE per day was sevenfold that of their daily walking training. VJ after walking remained unchanged compared with the baseline in AA (P > 0.2), while it was reduced by ~10% in PL (P < 0.01), although with no significant difference in the reduction between the groups (P > 0.4). The responses of other variables were not significantly different between groups (all, P > 0.2). Thus, trail walking in the mountains required a high-intensity effort for older people, while the effects of BCAA and arginine supplementation were modest in this condition.
An Empirical Study on Raman Peak Fitting and Its Application to Raman Quantitative Research.
Yuan, Xueyin; Mayanovic, Robert A
2017-10-01
Fitting experimentally measured Raman bands with theoretical model profiles is the basic operation for numerical determination of Raman peak parameters. In order to investigate the effects of peak modeling using various algorithms on peak fitting results, the representative Raman bands of mineral crystals, glass, fluids as well as the emission lines from a fluorescent lamp, some of which were measured under ambient light whereas others under elevated pressure and temperature conditions, were fitted using Gaussian, Lorentzian, Gaussian-Lorentzian, Voigtian, Pearson type IV, and beta profiles. From the fitting results of the Raman bands investigated in this study, the fitted peak position, intensity, area and full width at half-maximum (FWHM) values of the measured Raman bands can vary significantly depending upon which peak profile function is used in the fitting, and the most appropriate fitting profile should be selected depending upon the nature of the Raman bands. Specifically, the symmetric Raman bands of mineral crystals and non-aqueous fluids are best fit using Gaussian-Lorentzian or Voigtian profiles, whereas the asymmetric Raman bands are best fit using Pearson type IV profiles. The asymmetric O-H stretching vibrations of H 2 O and the Raman bands of soda-lime glass are best fit using several Gaussian profiles, whereas the emission lines from a florescent light are best fit using beta profiles. Multiple peaks that are not clearly separated can be fit simultaneously, provided the residuals in the fitting of one peak will not affect the fitting of the remaining peaks to a significant degree. Once the resolution of the Raman spectrometer has been properly accounted for, our findings show that the precision in peak position and intensity can be improved significantly by fitting the measured Raman peaks with appropriate profiles. Nevertheless, significant errors in peak position and intensity were still observed in the results from fitting of weak and wide Raman bands having unnormalized intensity/FWHM ratios lower than 200 counts/cm -1 .
Characterization of ultrafast laser-ablation plasma plumes at various Ar ambient pressures
Diwakar, P. K.; Harilal, S. S.; Phillips, M. C.; ...
2015-07-30
Expansion dynamics and internal plume structures of fs laser ablated brass plasma in Ar at various pressure levels ranging from vacuum to atmospheric were studied using multitude of diagnostic tools including time resolved and time integrated 2-dimensional imaging, optical time of flight measurements and visible emission spectroscopy. Temporal evolution of excited Cu and Zn species in the plume were imaged using band pass interference filters and compared its hydrodynamic expansion features with spectrally integrated images of the plume. 2D imaging coupled with monochromatic line selection showed several interesting features at various pressure levels which include velocity differences among the plumemore » species, emission intensity distribution, plasma temperature, electron density etc. Plume confinement, enhanced signal intensity, and dual peak structures in time-of-flight profiles were observed at intermediate pressure range of ~10 Torr. Optimum signal to background ratio was also observed in this pressure range. As a result, possible mechanisms for observed changes in plume shape, optical emission intensity and dual peak structures in time-of-flight profiles were discussed.« less
Exercise Training During Bed Rest Attenuates Deconditioning
NASA Technical Reports Server (NTRS)
Greenleaf, J. E.; Hargens, Alan R. (Technical Monitor)
1995-01-01
A 30-day 6 deg. head-down bed rest study was conducted to evaluate high-intensity, short-duration, alternating isotonic cycle ergometer exercise (ITE) training and high-intensity intermittent isokinetic exercise (IKE) training regiments designed to maintain peak VO2 and muscle mass, strength, and endurance at ambulatory control levels throughout prolonged bed rest. Other elements of the deconditioning (acclimation) syndrome, such as proprioception, psychological performance, hypovolemia, water balance, body composition, and orthostatic tolerance, were also measured. Compared with response during bed rest of the no exercise (NOE) control group: the ITE training regimen (a) maintained work capacity (peak VO2), (b) maintained plasma and red cell volume, (c) induced positive body water balance, (d) decreased quality of sleep and mental concentration, and (e) had no effect on the decrease in orthostatic tolerance; the IKE training regimen (a) attenuated the decrease in peak VO2 by 50%, (b) attenuated loss of red cell volume by 40%, but had no effect on loss of plasma volume, (c) induced positive body water balance, (d) had no adverse effect on quality of sleep or concentration, and (e) had no effect on the decrease in orthostatic tolerance. These findings suggest that various elements of the deconditioning syndrome can be manipulated by duration and intensity of ITE or IKE training regiments, and that several different training protocols will be required to maintain or restore physiological and psychological performance of individuals confined to prolonged bed rest.
Observations of the 12.3 micron Mg I emission line during a major solar flare
NASA Technical Reports Server (NTRS)
Deming, Drake; Jennings, Donald E.; Osherovich, Vladimir; Wiedemann, Gunter; Hewagama, Tilak
1990-01-01
The extremely Zeeman-sensitive 12.32 micron Mg I solar emission line was observed during a 3B/X5.7 solar flare on October 24, 1989. When compared to postflare values, Mg I emission-line intensity in the penumbral flare ribbon was 20 percent greater at the peak of the flare in soft X-rays, and the 12 micron continuum intensity was 7 percent greater. The flare also excited the emission line in the umbra where it is normally absent. The umbral flare emission exhibits a Zeeman splitting 200 G less than the adjacent penumbra, suggesting that it is excited at higher altitude. The absolute penumbral magnetic field strength did not change by more than 100 G between the flare peak and postflare period. However, a change in the inclination of the field lines, probably related to the formation and development of the flare loop system, was seen.
Tsaklis, Panagiotis; Malliaropoulos, Nikos; Mendiguchia, Jurdan; Korakakis, Vasileios; Tsapralis, Kyriakos; Pyne, Debasish; Malliaras, Peter
2015-01-01
Hamstring injuries are common in many sports, including track and field. Strains occur in different parts of the hamstring muscle but very little is known about whether common hamstring loading exercises specifically load different hamstring components. The purpose of this study was to investigate muscle activation of different components of the hamstring muscle during common hamstring loading exercises. Twenty elite female track and field athletes were recruited into this study, which had a single-sample, repeated-measures design. Each athlete performed ten hamstring loading exercises, and an electromyogram (EMG) was recorded from the biceps femoris and semitendinosus components of the hamstring. Hamstring EMG during maximal voluntary isometric contraction (MVIC) was used to normalize the mean data across ten repetitions of each exercise. An electrogoniometer synchronized to the EMG was used to determine whether peak EMG activity occurred during muscle-tendon unit lengthening, shortening, or no change in length. Mean EMG values were compared between the two recording sites for each exercise using the Student's t-test. The lunge, dead lift, and kettle swings were low intensity (<50% MVIC) and all showed higher EMG activity for semitendinosus than for biceps femoris. Bridge was low but approaching medium intensity, and the TRX, hamstring bridge, and hamstring curl were all medium intensity exercises (≥50% or <80% MVIC). The Nordic, fitball, and slide leg exercises were all high intensity exercises. Only the fitball exercise showed higher EMG activity in the biceps femoris compared with the semitendinosus. Only lunge and kettle swings showed peak EMG in the muscle-tendon unit lengthening phase and both these exercises involved faster speed. Some exercises selectively activated the lateral and medial distal hamstrings. Low, medium, and high intensity exercises were demonstrated. This information enables the clinician, strength and conditioning coach and physiotherapist to better understand intensity- and muscle-specific activation during hamstring muscle rehabilitation. Therefore, these results may help in designing progressive strengthening and rehabilitation and prevention programs.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lario, D.; Ho, G. C.; Decker, R. B.
Simultaneous measurements of solar energetic particle (SEP) events by two or more of the spacecraft located near 1 AU during the rising phase of solar cycle 24 (i.e., STEREO-A, STEREO-B, and near-Earth spacecraft such as ACE, SOHO, and GOES) are used to determine the longitudinal dependence of 71-112 keV electron, 0.7-3 MeV electron, 15-40 MeV proton, and 25-53 MeV proton peak intensities measured in the prompt component of SEP events. Distributions of the peak intensities for the selected 35 events with identifiable solar origin are approximated by the form exp [ - ({phi} - {phi}{sub 0}){sup 2}/2{sigma}{sup 2}], where {phi}more » is the longitudinal separation between the parent active region and the footpoint of the nominal interplanetary magnetic field (IMF) line connecting each spacecraft with the Sun, {phi}{sub 0} is the distribution centroid, and {sigma} determines the longitudinal gradient. The MESSENGER spacecraft, at helioradii R < 1 AU, allows us to determine a lower limit to the radial dependence of the 71-112 keV electron peak intensities measured along IMF lines. We find five events for which the nominal magnetic footpoint of MESSENGER was less than 20 Degree-Sign apart from the nominal footpoint of a spacecraft near 1 AU. Although the expected theoretical radial dependence for the peak intensity of the events observed along the same field line can be approximated by a functional form R {sup -{alpha}} with {alpha} < 3, we find two events for which {alpha} > 3. These two cases correspond to SEP events occurring in a complex interplanetary medium that favored the enhancement of peak intensities near Mercury but hindered the SEP transport to 1 AU.« less
Louie, Jeffrey C; Fujii, Naoto; Meade, Robert D; Kenny, Glen P
2016-11-01
Na + /K + -ATPase has been shown to regulate the sweating and cutaneous vascular responses during exercise; however, similar studies have not been conducted to assess the roles of the Na-K-2Cl co-transporter (NKCC) and K + channels. Additionally, it remains to be determined if these mechanisms underpinning the heat loss responses differ with exercise intensity. Eleven young (24 ± 4 years) males performed three 30-min semirecumbent cycling bouts at low (30% VO 2peak ), moderate (50% VO 2peak ), and high (70% VO 2peak ) intensity, respectively, each separated by 20-min recovery periods. Using intradermal microdialysis, four forearm skin sites were continuously perfused with either: (1) lactated Ringer solution (Control); (2) 6 mmol·L -1 ouabain (Na + /K + -ATPase inhibitor); (3) 10 mmol·L -1 bumetanide (NKCC inhibitor); or (4) 50 mmol·L -1 BaCl 2 (nonspecific K + channel inhibitor); sites at which we assessed local sweat rate (LSR) and cutaneous vascular conductance (CVC). Inhibition of Na + /K + -ATPase attenuated LSR compared to Control during the moderate and high-intensity exercise bouts (both P ˂ 0.01), whereas attenuations with NKCC and K + channel inhibition were only apparent during the high-intensity exercise bout (both P ≤ 0.05). Na + /K + -ATPase inhibition augmented CVC during all exercise intensities (all P ˂ 0.01), whereas CVC was greater with NKCC inhibition during the low-intensity exercise only (P ˂ 0.01) and attenuated with K + channel inhibition during the moderate and high-intensity exercise conditions (both P ˂ 0.01). We show that Na + /K + -ATPase, NKCC and K + channels all contribute to the regulation of sweating and cutaneous blood flow but their influence is dependent on the intensity of dynamic exercise. © 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.
Four Weeks of Off-Season Training Improves Peak Oxygen Consumption in Female Field Hockey Players
Funch, Lindsey T.; Lind, Erik; Van Langen, Deborah; Hokanson, James F.
2017-01-01
The purpose of the study was to examine the changes in peak oxygen consumption (V˙O2peak) and running economy (RE) following four-weeks of high intensity training and concurrent strength and conditioning during the off-season in collegiate female field hockey players. Fourteen female student-athletes (age 19.29 ± 0.91 years) were divided into two training groups, matched from baseline V˙O2peak: High Intensity Training (HITrun; n = 8) and High Intensity Interval Training (HIIT; n = 6). Participants completed 12 training sessions. HITrun consisted of 30 min of high-intensity running, while HIIT consisted of a series of whole-body high intensity Tabata-style intervals (75–85% of age predicted maximum heart rate) for a total of four minutes. In addition to the interval training, the off-season training included six resistance training sessions, three team practices, and concluded with a team scrimmage. V˙O2peak was measured pre- and post-training to determine the effectiveness of the training program. A two-way mixed (group × time) ANOVA showed a main effect of time with a statistically significant difference in V˙O2peak from pre- to post-testing, F(1, 12) = 12.657, p = 0.004, partial η2 = 0.041. Average (±SD) V˙O2peak increased from 44.64 ± 3.74 to 47.35 ± 3.16 mL·kg−1·min−1 for HIIT group and increased from 45.39 ± 2.80 to 48.22 ± 2.42 mL·kg−1·min−1 for HITrun group. Given the similar improvement in aerobic power, coaches and training staff may find the time saving element of HIIT-type conditioning programs attractive. PMID:29910449
Variation in light intensity with height and time from subsequent lightning return strokes
NASA Technical Reports Server (NTRS)
Jordan, D. M.; Uman, M. A.
1983-01-01
Photographic measurements of relative light intensity as a function of height and time have been conducted for seven return strokes in two lightning flashes at 7.8 and 8.7 km ranges, using film which possesses an approximately constant spectral response in the 300-670 nm range. The amplitude of the initial light peak is noted to decrease exponentially with height, with a decay constant of 0.6-0.8 km. The logarithm of the peak light intensity near the ground is found to be approximately proportional to the initial peak electric field intensity, implying that the current decrease with height may be much slower than the light decrease. Absolute light intensity is presently estimated through the integration of the photographic signals from individual channel segments, in order to simulate the calibrated, all-sky photoelectric data of Guo and Krider (1982).
Exercise intensity and the protection from postprandial vascular dysfunction in adolescents.
Bond, B; Gates, P E; Jackman, S R; Corless, L M; Williams, C A; Barker, A R
2015-06-01
Acute exercise transiently improves endothelial function and protects the vasculature from the deleterious effects of a high-fat meal (HFM). We sought to identify whether this response is dependent on exercise intensity in adolescents. Twenty adolescents (10 male, 14.3 ± 0.3 yr) completed three 1-day trials: 1) rest (CON); 2) 8 × 1 min cycling at 90% peak power with 75 s recovery [high-intensity interval exercise (HIIE)]; and 3) cycling at 90% of the gas exchange threshold [moderate-intensity exercise (MIE)] 1 h before consuming a HFM (1.50 g/kg fat). Macrovascular and microvascular endothelial function was assessed before and immediately after exercise and 3 h after the HFM by flow-mediated dilation (FMD) and laser Doppler imaging [peak reactive hyperemia (PRH)]. FMD and PRH increased 1 h after HIIE [P < 0.001, effect size (ES) = 1.20 and P = 0.048, ES = 0.56] but were unchanged after MIE. FMD and PRH were attenuated 3 h after the HFM in CON (P < 0.001, ES = 1.78 and P = 0.02, ES = 0.59). FMD remained greater 3 h after the HFM in HIIE compared with MIE (P < 0.001, ES = 1.47) and CON (P < 0.001, ES = 2.54), and in MIE compared with CON (P < 0.001, ES = 1.40). Compared with CON, PRH was greater 3 h after the HFM in HIIE (P = 0.02, ES = 0.71) and MIE (P = 0.02, ES = 0.84), with no differences between HIIE and MIE (P = 0.72, ES = 0.16). Plasma triacylglycerol concentration and total antioxidant status concentration were not different between trials. We conclude that exercise intensity plays an important role in protecting the vasculature from the deleterious effects of a HFM. Performing HIIE may provide superior vascular benefits than MIE in adolescent groups. Copyright © 2015 the American Physiological Society.
The Intensity Distribution for Gamma-Ray Bursts Observed with BATSE
NASA Technical Reports Server (NTRS)
Pendleton, Geoffrey N.; Mallozzi, Robert S.; Paciesas, William S.; Briggs, Michael S.; Preece, Robert D.; Koshut, Tom M.; Horack, John M.; Meegan, Charles A.; Fishman, Gerald J.; Hakkila, Jon;
1996-01-01
The intensity distributions of gamma-ray bursts observed by BATSE from 19 April 1991 to 19 September 1994 are presented. For this data set, (V/V(sub max)) is 0.329 +/- 0.011, which is 15.5 sigma away from the value of 0.5 expected for a homogeneous distribution. Standard cosmological model parameters are obtained by fitting the differentially binned peak flux distribution expressed in units of photons cm(exp -2) s(exp -1) in the energy range 50-300 keV. The value of z calculated for a peak flux of 1 photon cm(exp -2) s(exp -1) is 0.8 +/- 0.33. The procedures used to produce the peak flux data and C(sub p)/C(sub lim) data are presented. The differences between the two representations of burst intensity are emphasized so that researchers can determine which type of data is most appropriate for their studies. The sky sensitivity correction as a function of intensity for the peak flux data is also described.
Fritea, Luminţa; Tertiş, Mihaela; Cristea, Cecilia; Săndulescu, Robert
2013-01-01
The electrochemical behavior of ascorbic acid and uric acid on glassy carbon bare electrodes and ones modified with β-cyclodextrin entrapped in polyethyleneimine film has been investigated using square wave voltammetry. The electrode modification was achieved in order to separate the voltammetric peaks of ascorbic acid and uric acid when present in the same solution. On the modified electrodes the potential of the oxidation peak of the ascorbic acid was shifted to more negative values by over 0.3 V, while in the case of uric acid, the negative potential shift was about 0.15 V compared to the bare glassy carbon electrode. When the two compounds were found together in the solution, on the bare electrode only a single broad signal was observed, while on the modified electrode the peak potentials of these two compounds were separated by 0.4 V. When the uric acid concentration remained constant, the peak intensity of the ascorbic acid is increased linearly with the concentration (r2 = 0.996) and when the ascorbic acid concentration remains constant, the peak intensity of the uric acid increased linearly with the concentration (r2 = 0.992). FTIR measurements supported the formation of inclusion complexes. In order to characterize the modification of the electrodes microscopic studies were performed. The modified electrodes were successfully employed for the determination of ascorbic acid in pharmaceutical formulations with a detection limit of 0.22 μM. PMID:24287544
Quantitative characterization of fatty liver disease using x-ray scattering
NASA Astrophysics Data System (ADS)
Elsharkawy, Wafaa B.; Elshemey, Wael M.
2013-11-01
Nonalcoholic fatty liver disease (NAFLD) is a dynamic condition in which fat abnormally accumulates within the hepatocytes. It is believed to be a marker of risk of later chronic liver diseases, such as liver cirrhosis and carcinoma. The fat content in liver biopsies determines its validity for liver transplantation. Transplantation of livers with severe NAFLD is associated with a high risk of primary non-function. Moreover, NAFLD is recognized as a clinically important feature that influences patient morbidity and mortality after hepatic resection. Unfortunately, there is a lack in a precise, reliable and reproducible method for quantification of NAFLD. This work suggests a method for the quantification of NAFLD. The method is based on the fact that fatty liver tissue would have a characteristic x-ray scattering profile with a relatively intense fat peak at a momentum transfer value of 1.1 nm-1 compared to a soft tissue peak at 1.6 nm-1. The fat content in normal and fatty liver is plotted against three profile characterization parameters (ratio of peak intensities, ratio of area under peaks and ratio of area under fat peak to total profile area) for measured and Monte Carlo simulated x-ray scattering profiles. Results show a high linear dependence (R2>0.9) of the characterization parameters on the liver fat content with a reported high correlation coefficient (>0.9) between measured and simulated data. These results indicate that the current method probably offers reliable quantification of fatty liver disease.
High-intensity Interval Training Frequency: Cardiometabolic Effects and Quality of Life.
Stavrinou, Pinelopi S; Bogdanis, Gregory C; Giannaki, Christoforos D; Terzis, Gerasimos; Hadjicharalambous, Marios
2018-02-01
The effects of high intensity interval training (HIIT) frequency on cardiometabolic health and quality of life were examined in 35 healthy inactive adults (age: 31.7±2.6 yrs, VO 2 peak: 32.7±7.4 ml·: kg -1 ·: min -1 ). Participants were randomly assigned to a control (CON) and two training groups, which performed 10×60-s cycling at ~83% of peak power, two (HIIT-2) or three times per week (HIIT-3) for eight weeks. Compared with CON, both training regimes resulted in similar improvements in VO 2 peak (HIIT-2: 10.8%, p=0.048, HIIT-3: 13.6%, p=0.017), waist circumference (HIIT-2: -1.4 cm, p=0.048, HIIT-3: -2.4 cm, p=0.028), thigh cross-sectional area (HIIT-2: 11.4 cm 2 , p=0.001, HIIT-3: 9.3 cm 2 , p=0.001) and the physical health component of quality of life (HIIT-2: 8.4, p=0.001, HIIT-3: 12.2, p=0.001). However, HIIT-3 conferred additional health-related benefits by reducing total body and trunk fat percentage (p<0.05, compared with CON), total cholesterol and low-density lipoprotein-cholesterol (p<0.02, compared with CON) and by improving the mental component of quality of life (p=0.045, compared with CON). In conclusion, performing HIIT only twice per week is effective in promoting cardiometabolic health-related adaptations and quality of life in inactive adults. However, higher HIIT frequency is required for an effect on fat deposits, cholesterol and mental component of well-being. © Georg Thieme Verlag KG Stuttgart · New York.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heo, T; Ye, S
2015-06-15
Purpose: To study a feasibility of micro-dosimetry with high dose-sensitivity and resolution using two-dimensional Raman mapping on the basis of carbon bonds concentration of radiochromic films Methods: Unlaminated EBT3 films with the purpose of maximal Raman data acquisition were irradiated by 6 MV beam from 5 MU to 1000 MU at the reference condition. Each film was irradiated with shielding material of lead blocking on the half of film as well as the jaw open in half for distinct dose contrast. Raman peaks of 2070 cm-1, 2095 cm-1, and 2115 cm-1 were major subjects to study, which are assumed tomore » be the spectroscopy of carbon triple bonds of monomers, carbon double bonds of polymers, and carbon triple bonds of polymers, respectively. Laser exposure for Raman spectroscopy generated peak’s trend due to polymerization by laser output and this trend was utilized to find out basic peaks related to polymerization process. The relative dose contrast in each one film was detected by Raman spectroscopy with the aid of an auto-scanning stage, comparing the dose contrast between non-irradiated area and irradiated area. Raman spatial resolution was enhanced up to 20 micrometers, assuming the spatial uniformity of radio¬active rod-shaped LiPCDA crystals. An optical scanner with 9600 dpi was used to scan the red-channel intensity to read the dose contrast for 5 MU delivered film. Results: The peak intensity for Raman wavenumber of 2070 cm-1 was used for mapping since it reflected the different peak intensities based on polymerization degree by irradiation. Dose contrast from 1000MU to 5 MU was distinguished by Raman mapping analysis, whereas optical intensity of red-channel didn’t show any difference. Conclusion: In consideration of laser effect, the quantitative analysis based on raw data of Raman mapping could provide more statistically reliable dosimetry than point measurements.« less
Effective precipitation duration for runoff peaks based on catchment modelling
NASA Astrophysics Data System (ADS)
Sikorska, A. E.; Viviroli, D.; Seibert, J.
2018-01-01
Despite precipitation intensities may greatly vary during one flood event, detailed information about these intensities may not be required to accurately simulate floods with a hydrological model which rather reacts to cumulative precipitation sums. This raises two questions: to which extent is it important to preserve sub-daily precipitation intensities and how long does it effectively rain from the hydrological point of view? Both questions might seem straightforward to answer with a direct analysis of past precipitation events but require some arbitrary choices regarding the length of a precipitation event. To avoid these arbitrary decisions, here we present an alternative approach to characterize the effective length of precipitation event which is based on runoff simulations with respect to large floods. More precisely, we quantify the fraction of a day over which the daily precipitation has to be distributed to faithfully reproduce the large annual and seasonal floods which were generated by the hourly precipitation rate time series. New precipitation time series were generated by first aggregating the hourly observed data into daily totals and then evenly distributing them over sub-daily periods (n hours). These simulated time series were used as input to a hydrological bucket-type model and the resulting runoff flood peaks were compared to those obtained when using the original precipitation time series. We define then the effective daily precipitation duration as the number of hours n, for which the largest peaks are simulated best. For nine mesoscale Swiss catchments this effective daily precipitation duration was about half a day, which indicates that detailed information on precipitation intensities is not necessarily required to accurately estimate peaks of the largest annual and seasonal floods. These findings support the use of simple disaggregation approaches to make usage of past daily precipitation observations or daily precipitation simulations (e.g. from climate models) for hydrological modeling at an hourly time step.
Gruen, Margaret E.; Alfaro-Córdoba, Marcela; Thomson, Andrea E.; Worth, Alicia C.; Staicu, Ana-Maria; Lascelles, B. Duncan X.
2017-01-01
Introduction and objectives Accelerometry is used as an objective measure of physical activity in humans and veterinary species. In cats, one important use of accelerometry is in the study of therapeutics designed to treat degenerative joint disease (DJD) associated pain, where it serves as the most widely applied objective outcome measure. These analyses have commonly used summary measures, calculating the mean activity per-minute over days and comparing between treatment periods. While this technique has been effective, information about the pattern of activity in cats is lost. In this study, functional data analysis was applied to activity data from client-owned cats with (n = 83) and without (n = 15) DJD. Functional data analysis retains information about the pattern of activity over the 24-hour day, providing insight into activity over time. We hypothesized that 1) cats without DJD would have higher activity counts and intensity of activity than cats with DJD; 2) that activity counts and intensity of activity in cats with DJD would be inversely correlated with total radiographic DJD burden and total orthopedic pain score; and 3) that activity counts and intensity would have a different pattern on weekends versus weekdays. Results and conclusions Results showed marked inter-cat variability in activity. Cats exhibited a bimodal pattern of activity with a sharp peak in the morning and broader peak in the evening. Results further showed that this pattern was different on weekends than weekdays, with the morning peak being shifted to the right (later). Cats with DJD showed different patterns of activity from cats without DJD, though activity and intensity were not always lower; instead both the peaks and troughs of activity were less extreme than those of the cats without DJD. Functional data analysis provides insight into the pattern of activity in cats, and an alternative method for analyzing accelerometry data that incorporates fluctuations in activity across the day. PMID:28099449
Development of a Double-Gauss Lens Based Setup for Optoacoustic Applications
Choi, Hojong; Ryu, Jae-Myung; Yeom, Jung-Yeol
2017-01-01
In optoacoustic (photoacoustic) systems, different echo signal intensities such as amplitudes, center frequencies, and bandwidths need to be compensated by utilizing variable gain or time-gain compensation amplifiers. However, such electronic components can increase system complexities and signal noise levels. In this paper, we introduce a double-Gauss lens to generate a large field of view with uniform light intensity due to the low chromatic aberrations of the lens, thus obtaining uniform echo signal intensities across the field of view of the optoacoustic system. In order to validate the uniformity of the echo signal intensities in the system, an in-house transducer was placed at various positions above a tissue sample and echo signals were measured and compared with each other. The custom designed double-Gauss lens demonstrated negligible light intensity variation (±1.5%) across the illumination field of view (~2 cm diameter). When the transducer was used to measure echo signal from an eye of a bigeye tuna within a range of ±1 cm, the peak-to-peak amplitude, center frequency, and their −6 dB bandwidth variations were less than 2 mV, 1 MHz, and 6%, respectively. The custom designed double-Gauss lens can provide uniform light beam across a wide area while generating insignificant echo signal variations, and thus can lower the burden of the receiving electronics or signal processing in the optoacoustic system. PMID:28273794
Extension of filament propagation in water with Bessel-Gaussian beams
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kaya, G.; Sayrac, M.; Boran, Y.
We experimentally studied intense femtosecond pulse filamentation and propagation in water for Bessel-Gaussian beams with different numbers of radial modal lobes. The transverse modes of the incident Bessel-Gaussian beam were created from a Gaussian beam of a Ti:sapphire laser system by using computer generated hologram techniques. We found that filament propagation length increased with increasing number of lobes under the conditions of the same peak intensity, pulse duration, and the size of the central peak of the incident beam, suggesting that the radial modal lobes may serve as an energy reservoir for the filaments formed by the central intensity peak.
Kilometric shock-associated events and microwave bursts
NASA Technical Reports Server (NTRS)
Kundu, M. R.; Macdowall, R. J.; Stone, R. G.
1990-01-01
The peak times of impulsive microwaves bursts are compared with those of shock-associated (SA) kilometric radio events. The first peaks in these two frequency regimes are usually well-correlated in time, but the last peaks of the SA events observed at 1 MHz occur an average of 20 min after the last impulsive microwave peaks. In some cases, the SA events overlap in time with the post-burst increases of microwave bursts; sometimes there is general correspondence in their intensity time profiles. These observations suggest that the earlier components of the SA events are usually caused by electrons accelerated in or near the microwave source region. The possibility that the later components of some SA events could be associated with nonthermal electrons responsible for microwave post-burst increases, although they have traditionally been attributed to electrons accelerated at type II burst producing shocks in the upper corona is discussed.
Kim, Young-Sun; Lee, Jeong-Won; Choi, Chel Hun; Kim, Byoung-Gie; Bae, Duk-Soo; Rhim, Hyunchul; Lim, Hyo Keun
2016-03-01
To evaluate the relationships between T2 signal intensity and semiquantitative perfusion magnetic resonance (MR) parameters of uterine fibroids in patients who were screened for MR-guided high-intensity focused ultrasound (HIFU) ablation. Institutional review board approval was granted, and informed consents were waived. One hundred seventy most symptom-relevant, nondegenerated uterine fibroids (mean diameter, 7.3 cm; range, 3.0-17.2 cm) in 170 women (mean age, 43.5 years; range, 24-56 years) undergoing screening MR examinations for MR-guided HIFU ablation from October 2009 to April 2014 were retrospectively analyzed. Fibroid signal intensity was assessed as the ratio of the fibroid T2 signal intensity to that of skeletal muscle. Parameters of semiquantitative perfusion MR imaging obtained during screening MR examination (peak enhancement, percentage of relative peak enhancement, time to peak [in seconds], wash-in rate [per seconds], and washout rate [per seconds]) were investigated to assess their relationships with T2 signal ratio by using multiple linear regression analysis. Correlations between T2 signal intensity and independently significant perfusion parameters were then evaluated according to fibroid type by using Spearman correlation test. Multiple linear regression analysis revealed that relative peak enhancement showed an independently significant correlation with T2 signal ratio (Β = 0.004, P < .001). Submucosal intracavitary (n = 20, ρ = 0.275, P = .240) and type III (n = 18, ρ = 0.082, P = .748) fibroids failed to show significant correlations between perfusion and T2 signal intensity, while significant correlations were found for all other fibroid types (ρ = 0.411-0.629, P < .05). In possible candidates for MR-guided HIFU ablation, the T2 signal intensity of nondegenerated uterine fibroids showed an independently significant positive correlation with relative peak enhancement in most cases, except those of submucosal intracavitary or type III fibroids.
Enhanced Raman Scattering from InSb Nanodots; Temperature and Laser-Power Dependent Studies
NASA Astrophysics Data System (ADS)
Wada, Noboru; Takayama, Haruki; Morohashi, Satoshi
2010-03-01
InSb nanodots were uniquely fabricated by vapor-transport on a Si substrate which had previously been bombarded by FBI Ga ions. The InSb nanodots were then examined by spatially-resolved Raman scattering using an Ar-ion laser (λ= 514.5 and 488 nm with P=1˜15 mW) with an optical microscope and CCD detector. In addition to the TO and LO peaks of InSb observed at ˜180 and 191 cm-1 respectively, two peaks were observed at ˜110 and 150 cm-1. Those Raman peaks were tentatively attributed to the 2TA and TO-TA second-order Raman processes. Those two peak intensities appeared to grow at the expense of the TO and LO Raman peak intensities with increasing the sample temperature from 10 K to 450 K. Also, the two-phonon peak intensities increased non-linearly with the probing laser power used. Hot carriers and their interactions with phonons in the restricted regions will be discussed together with Raman scattering results obtained from single-crystal InSb.
Chen, B; Kadowaki, Y; Inoue, S; Ohkohchi, M; Zhao, X; Ando, Y
2010-06-01
The new peak (near 1850 cm(-1)) assigned to carbon linear chain included in the centre of very thin innermost multiwalled carbon nanotubes (MWNTs) has been verified by Raman spectroscopy. These MWNTs were produced by dc arc discharge of pure graphite rods in pure hydrogen gas and existed in the cathode deposit. In this paper, we clarified that the new Raman-peaks could also be observed in the cathode deposit including MWNTs produced by hydrogen dc arc discharge using graphite electrode with added Y or La. By changing the quantity of addition (Y or La), dc arc current and pressure of ambient hydrogen gas, the optimum condition to get maximum intensity of the new Raman-peaks was obtained. For the case of 1 wt% La, dc 50 A, H2 pressure of 50 Torr was found to be optimum, and the intensity of new Raman-peak was even higher than the G-band peak. For the case of 1 wt% Y, dc 50 A, H2 pressure of 50 Torr was optimum, but the intensity of new Raman-peak was weaker than the G-band peak. Transmission electron microscopy observation revealed that the crystallinity of MWNTs produced with pure graphite rod was better than those produced with added Y or La.
Do intensive care data on respiratory infections reflect influenza epidemics?
Koetsier, Antonie; van Asten, Liselotte; Dijkstra, Frederika; van der Hoek, Wim; Snijders, Bianca E; van den Wijngaard, Cees C; Boshuizen, Hendriek C; Donker, Gé A; de Lange, Dylan W; de Keizer, Nicolette F; Peek, Niels
2013-01-01
Severe influenza can lead to Intensive Care Unit (ICU) admission. We explored whether ICU data reflect influenza like illness (ILI) activity in the general population, and whether ICU respiratory infections can predict influenza epidemics. We calculated the time lag and correlation between ILI incidence (from ILI sentinel surveillance, based on general practitioners (GP) consultations) and percentages of ICU admissions with a respiratory infection (from the Dutch National Intensive Care Registry) over the years 2003-2011. In addition, ICU data of the first three years was used to build three regression models to predict the start and end of influenza epidemics in the years thereafter, one to three weeks ahead. The predicted start and end of influenza epidemics were compared with observed start and end of such epidemics according to the incidence of ILI. Peaks in respiratory ICU admissions lasted longer than peaks in ILI incidence rates. Increases in ICU admissions occurred on average two days earlier compared to ILI. Predicting influenza epidemics one, two, or three weeks ahead yielded positive predictive values ranging from 0.52 to 0.78, and sensitivities from 0.34 to 0.51. ICU data was associated with ILI activity, with increases in ICU data often occurring earlier and for a longer time period. However, in the Netherlands, predicting influenza epidemics in the general population using ICU data was imprecise, with low positive predictive values and sensitivities.
Kong, Zhaowei; Sun, Shengyan; Liu, Min; Shi, Qingde
2016-01-01
This study was to determine the effects of five-week high-intensity interval training (HIIT) on cardiorespiratory fitness, body composition, blood glucose, and relevant systemic hormones when compared to moderate-intensity continuous training (MICT) in overweight and obese young women. Methods . Eighteen subjects completed 20 sessions of HIIT or MICT for five weeks. HIIT involved 60 × 8 s cycling at ~90% of peak oxygen consumption ([Formula: see text]) interspersed with 12 s recovery, whereas MICT involved 40-minute continuous cycling at 65% of [Formula: see text]. [Formula: see text], body composition, blood glucose, and fasting serum hormones, including leptin, growth hormone, testosterone, cortisol, and fibroblast growth factor 21, were measured before and after training. Results . Both exercise groups achieved significant improvements in [Formula: see text] (+7.9% in HIIT versus +11.7% in MICT) and peak power output (+13.8% in HIIT versus +21.9% in MICT) despite no training effects on body composition or the relevant systemic hormones. Blood glucose tended to be decreased after the intervention ( p = 0.062). The rating of perceived exertion in MICT was higher than that in HIIT ( p = 0.042). Conclusion . Compared with MICT, short-term HIIT is more time-efficient and is perceived as being easier for improving cardiorespiratory fitness and fasting blood glucose for overweight and obese young women.
Thomson scattering in high-intensity chirped laser pulses
DOE Office of Scientific and Technical Information (OSTI.GOV)
Holkundkar, Amol R., E-mail: amol.holkundkar@pilani.bits-pilani.ac.in; Harvey, Chris, E-mail: christopher.harvey@chalmers.se; Marklund, Mattias, E-mail: mattias.marklund@chalmers.se
2015-10-15
We consider the Thomson scattering of an electron in an ultra-intense laser pulse. It is well known that at high laser intensities, the frequency and brilliance of the emitted radiation will be greatly reduced due to the electron losing energy before it reaches the peak field. In this work, we investigate the use of a small frequency chirp in the laser pulse in order to mitigate this effect of radiation reaction. It is found that the introduction of a negative chirp means the electron enters a high frequency region of the field while it still has a large proportion ofmore » its original energy. This results in a significant enhancement of the frequency and intensity of the emitted radiation as compared to the case without chirping.« less
Effects of Solar Activities on the Transient Luminous Events
NASA Astrophysics Data System (ADS)
Wu, Y.; Williams, E.; Chou, J.; Lee, L.; Huang, S.; Chang, S.; Chen, A. B.; Kuo, C.; Su, H.; Hsu, R.; Frey, H. U.; Takahashi, Y.; Lee, L.
2013-12-01
The Imager of Sprite and Upper Atmosphere Lightning (ISUAL) onboard the Formosat-2 was launched in May 2004; since then, it has continuously observed transient luminous events (TLEs) within the +/-60 degree of latitude for nearly 10 years. Due to ISUAL's long-term observations, the possible correlation between the TLE and the solar activity can be explored. Among the ISUAL TLEs, elves, which occur at the mesospheric altitude ~90 km and are caused by the heating incurred by the lightning-launched electromagnetic pulse of the lower ionosphere boundary are the most numerous and are the most suitable for this type of study. In previous studies, the elve distribution has proved to be a good surrogate for the lightning with exceptional peak current globally. ISUAL records the occurrence time and the height and location of elves, and the spectral emission intensities at six different band pass including the FUV N2 Lyman-Birge-Hopfield (LBH) band, which is a dominant emission in elves. The LBH intensity not only reflects the peak current of parent lightning, but may also represent the solar-activity-driven-lighting's perturbation to the ionosphere. In this study, we first examine whether the 11-year solar cycle affects the elve activity and altitude by analyzing the elve occurrence rates and heights in different latitudinal regions. To avoid the climatological and instrumental biases in the elve observations, the effects arising from the ENSO and moonlight must be carefully eliminated. Besides, we will discuss the elve variation in shorter time scale due to strong and sudden change of solar activity. Since the ion density of the mesosphere at mid-latitude may be significantly altered during/after a strong corona mass ejection (CME).Furthermore, it has been proven that the changes in the solar X-ray flux dominate the variations in the conductivity profile within the upper characteristic ELF layer (the 90-100km portion of the E-region). we will compare the variation of emission intensity of elves with and without intense CME/x-ray flux events to quantify the possible effects of ionospheric perturbations due to solar activity. We have selected elves over the winter storm track in the Pacific Ocean region northeast of Japan due to the strong elve activity there during northern hemisphere winters in order to make sure the sufficient events for statistical analysis. The peak current of the parent lightning for the ISUAL elves can be inferred from the lightning energy recorded by the WWLLN. With the inferred peak current, the LBH band emission intensity in elves can be computed. Finally, the theoretical and the observed LBH band intensity for elves are to be compared; the difference may come from the effect of intense CME/x-ray flux .Details of the data analyses and the preliminary results will be presented fully in the report.
Yamashina, Yoshihiro; Yokoyama, Hisayo; Naghavi, Nooshin; Hirasawa, Yoshikazu; Takeda, Ryosuke; Ota, Akemi; Imai, Daiki; Miyagawa, Toshiaki; Okazaki, Kazunobu
2016-05-01
The purpose of the present study was to investigate the effect of walking in water on respiratory muscle fatigue compared with that of walking on land at the same exercise intensity. Ten healthy males participated in 40-min treadmill walking trials on land and in water at an intensity of 60% of peak oxygen consumption. Respiratory function and respiratory muscle strength were evaluated before and after walking trials. Inspiratory muscle strength and forced expiratory volume in 1 s were significantly decreased immediately after walking in water, and expiratory muscle strength was significantly decreased immediately and 5 min after walking in water compared with the baseline. The decreases of inspiratory and expiratory muscle strength were significantly greater compared with that after walking on land. In conclusion, greater inspiratory and expiratory muscle fatigue was induced by walking in water than by walking on land at the same exercise intensity in healthy young men.
Norris, G; McConnell, G
2010-03-01
A novel bi-directional pump geometry that nonlinearly increases the nonlinear optical conversion efficiency of a synchronously pumped optical parametric oscillator (OPO) is reported. This bi-directional pumping method synchronizes the circulating signal pulse with two counter-propagating pump pulses within a linear OPO resonator. Through this pump scheme, an increase in nonlinear optical conversion efficiency of 22% was achieved at the signal wavelength, corresponding to a 95% overall increase in average power. Given an almost unchanged measured pulse duration of 260 fs under optimal performance conditions, this related to a signal wavelength peak power output of 18.8 kW, compared with 10 kW using the traditional single-pass geometry. In this study, a total effective peak intensity pump-field of 7.11 GW/cm(2) (corresponding to 3.55 GW/cm(2) from each pump beam) was applied to a 3 mm long periodically poled lithium niobate crystal, which had a damage threshold intensity of 4 GW/cm(2), without impairing crystal integrity. We therefore prove the application of this novel pump geometry provides opportunities for power-scaling of synchronously pumped OPO systems together with enhanced nonlinear conversion efficiency through relaxed damage threshold intensity conditions.
Calculating the electron temperature in the lightning channel by continuous spectrum
NASA Astrophysics Data System (ADS)
Xiangcheng, DONG; Jianhong, CHEN; Xiufang, WEI; Ping, YUAN
2017-12-01
Based on the theory of plasma continuous radiation, the relationship between the emission intensity of bremsstrahlung and recombination radiation and the plasma electron temperature is obtained. During the development process of a return stroke of ground flash, the intensity of continuous radiation spectrum is separated on the basis of the spectrums with obviously different luminous intensity at two moments. The electron temperature of the lightning discharge channel is obtained through the curve fitting of the continuous spectrum intensity. It is found that electron temperature increases with the increase of wavelength and begins to reduce after the peak. The peak temperature of the two spectra is close to 25 000 K. To be compared with the result of discrete spectrum, the electron temperature is fitted by the O I line and N II line of the spectrum respectively. The comparison shows that the high temperature value is in good agreement with the temperature of the lightning core current channel obtained from the ion line information, and the low temperature at the high band closes to the calculation result of the atomic line, at a low band is lower than the calculation of the atomic line, which reflects the temperature of the luminous channel of the outer corona.
Thermal characteristic of limonite ore upon calcination and reduction
NASA Astrophysics Data System (ADS)
Febriana, Eni; Manaf, Azwar; Prasetyo, A. B.; Mayangsari, W.
2018-05-01
Thermal characteristics of the limonite laterite ore types have been studied using TG / DTA. There are four endothermic peaks at 250, 646, 900, and 1023 °C with a total mass loss of 10.07wt%. These four peaks correspond to the XRD results on samples calcined at 600-1000 °C. Analysis of TG / DTA to the mixture of limonite and graphite showed two endothermic reaction peaks at 641 and 900 °C and an exothermic peak at 1180 °C. Reduction of the limonite-graphite mixture was done by heating at 800-1100 °C for 1 hour, and the reduced samples were analyzed using XRD. The results indicate that the reduction process proceed completely at higher temperatures, indicated by the increasing intensity of kamacite and Fe metal phase, and the decrease of peak intensity of carbon due to reaction with metal oxides. At 1100 °C, intensity of Fe-metal decreased due to sintering of Fe which may occur because the temperature was too high.
Echo decorrelation imaging of ex vivo HIFU and bulk ultrasound ablation using image-treat arrays
NASA Astrophysics Data System (ADS)
Fosnight, Tyler R.; Hooi, Fong Ming; Colbert, Sadie B.; Keil, Ryan D.; Barthe, Peter G.; Mast, T. Douglas
2017-03-01
In this study, the ability of ultrasound echo decorrelation imaging to map and predict heat-induced cell death was tested using bulk ultrasound thermal ablation, high intensity focused ultrasound (HIFU) thermal ablation, and pulse-echo imaging of ex vivo liver tissue by a custom image-treat array. Tissue was sonicated at 5.0 MHz using either pulses of unfocused ultrasound (N=12) (7.5 s, 50.9-101.8 W/cm2 in situ spatial-peak, temporal-peak intensity) for bulk ablation or focused ultrasound (N=21) (1 s, 284-769 W/cm2 in situ spatial-peak, temporal-peak intensity and focus depth of 10 mm) for HIFU ablation. Echo decorrelation and integrated backscatter (IBS) maps were formed from radiofrequency pulse-echo images captured at 118 frames per second during 5.0 s rest periods, beginning 1.1 s after each sonication pulse. Tissue samples were frozen at -80˚C, sectioned, vitally stained, imaged, and semi-automatically segmented for receiver operating characteristic (ROC) analysis. ROC curves were constructed to assess prediction performance for echo decorrelation and IBS. Logarithmically scaled mean echo decorrelation in non-ablated and ablated tissue regions before and after electronic noise and motion correction were compared. Ablation prediction by echo decorrelation and IBS was significant for both focused and bulk ultrasound ablation. The log10-scaled mean echo decorrelation was significantly greater in regions of ablation for both HIFU and bulk ultrasound ablation. Echo decorrelation due to electronic noise and motion was significantly reduced by correction. These results suggest that ultrasound echo decorrelation imaging is a promising approach for real-time prediction of heat-induced cell death for guidance and monitoring of clinical thermal ablation, including radiofrequency ablation and HIFU.
NASA Astrophysics Data System (ADS)
Khokhlova, V. A.; Bessonova, O. V.; Soneson, J. E.; Canney, M. S.; Bailey, M. R.; Crum, L. A.
2010-03-01
Nonlinear propagation effects result in the formation of weak shocks in high intensity focused ultrasound (HIFU) fields. When shocks are present, the wave spectrum consists of hundreds of harmonics. In practice, shock waves are modeled using a finite number of harmonics and measured with hydrophones that have limited bandwidths. The goal of this work was to determine how many harmonics are necessary to model or measure peak pressures, intensity, and heat deposition rates of the HIFU fields. Numerical solutions of the Khokhlov-Zabolotskaya-Kuznetzov-type (KZK) nonlinear parabolic equation were obtained using two independent algorithms, compared, and analyzed for nonlinear propagation in water, in gel phantom, and in tissue. Measurements were performed in the focus of the HIFU field in the same media using fiber optic probe hydrophones of various bandwidths. Experimental data were compared to the simulation results.
NASA Astrophysics Data System (ADS)
Abeysekara, Saman; Damiran, Daalkhaijav; Yu, Peiqiang
2013-02-01
The objectives of this study were (i) to determine lipid related molecular structures components (functional groups) in feed combination of cereal grain (barley, Hordeum vulgare) and wheat (Triticum aestivum) based dried distillers grain solubles (wheat DDGSs) from bioethanol processing at five different combination ratios using univariate and multivariate molecular spectral analyses with infrared Fourier transform molecular spectroscopy, and (ii) to correlate lipid-related molecular-functional structure spectral profile to nutrient profiles. The spectral intensity of (i) CH3 asymmetric, CH2 asymmetric, CH3 symmetric and CH2 symmetric groups, (ii) unsaturation (Cdbnd C) group, and (iii) carbonyl ester (Cdbnd O) group were determined. Spectral differences of functional groups were detected by hierarchical cluster analysis (HCA) and principal components analysis (PCA). The results showed that the combination treatments significantly inflicted modifications (P < 0.05) in nutrient profile and lipid related molecular spectral intensity (CH2 asymmetric stretching peak height, CH2 symmetric stretching peak height, ratio of CH2 to CH3 symmetric stretching peak intensity, and carbonyl peak area). Ratio of CH2 to CH3 symmetric stretching peak intensity, and carbonyl peak significantly correlated with nutrient profiles. Both PCA and HCA differentiated lipid-related spectrum. In conclusion, the changes of lipid molecular structure spectral profiles through feed combination could be detected using molecular spectroscopy. These changes were associated with nutrient profiles and functionality.
Blue light effect on retinal pigment epithelial cells by display devices.
Moon, Jiyoung; Yun, Jieun; Yoon, Yeo Dae; Park, Sang-Il; Seo, Young-Jun; Park, Won-Sang; Chu, Hye Yong; Park, Keun Hong; Lee, Myung Yeol; Lee, Chang Woo; Oh, Soo Jin; Kwak, Young-Shin; Jang, Young Pyo; Kang, Jong Soon
2017-05-22
Blue light has high photochemical energy and induces cell apoptosis in retinal pigment epithelial cells. Due to its phototoxicity, retinal hazard by blue light stimulation has been well demonstrated using high intensity light sources. However, it has not been studied whether blue light in the displays, emitting low intensity light, such as those used in today's smartphones, monitors, and TVs, also causes apoptosis in retinal pigment epithelial cells. We attempted to examine the blue light effect on human adult retinal epithelial cells using display devices with different blue light wavelength ranges, the peaks of which specifically appear at 449 nm, 458 nm, and 470 nm. When blue light was illuminated on A2E-loaded ARPE-19 cells using these displays, the display with a blue light peak at a shorter wavelength resulted in an increased production of reactive oxygen species (ROS). Moreover, the reduction of cell viability and induction of caspase-3/7 activity were more evident in A2E-loaded ARPE-19 cells after illumination by the display with a blue light peak at a shorter wavelength, especially at 449 nm. Additionally, white light was tested to examine the effect of blue light in a mixed color illumination with red and green lights. Consistent with the results obtained using only blue light, white light illuminated by display devices with a blue light peak at a shorter wavelength also triggered increased cell death and apoptosis compared to that illuminated by display devices with a blue light peak at longer wavelength. These results show that even at the low intensity utilized in the display devices, blue light can induce ROS production and apoptosis in retinal cells. Our results also suggest that the blue light hazard of display devices might be highly reduced if the display devices contain less short wavelength blue light.
Boyne, Pierce; Welge, Jeffrey; Kissela, Brett; Dunning, Kari
2017-03-01
To assess the influence of dosing parameters and patient characteristics on the efficacy of aerobic exercise (AEX) poststroke. A systematic review was conducted using PubMed, MEDLINE, Cumulative Index of Nursing and Allied Health Literature, Physiotherapy Evidence Database, and Academic Search Complete. Studies were selected that compared an AEX group with a nonaerobic control group among ambulatory persons with stroke. Extracted outcome data included peak oxygen consumption (V˙o 2 peak) during exercise testing, walking speed, and walking endurance (6-min walk test). Independent variables of interest were AEX mode (seated or walking), AEX intensity (moderate or vigorous), AEX volume (total hours), stroke chronicity, and baseline outcome scores. Significant between-study heterogeneity was confirmed for all outcomes. Pooled AEX effect size estimates (AEX group change minus control group change) from random effects models were V˙o 2 peak, 2.2mL⋅kg -1 ⋅min -1 (95% confidence interval [CI], 1.3-3.1mL⋅kg -1 ⋅min -1 ); walking speed, .06m/s (95% CI, .01-.11m/s); and 6-minute walk test distance, 29m (95% CI, 15-42m). In meta-regression, larger V˙o 2 peak effect sizes were significantly associated with higher AEX intensity and higher baseline V˙o 2 peak. Larger effect sizes for walking speed and the 6-minute walk test were significantly associated with a walking AEX mode. In contrast, seated AEX did not have a significant effect on walking outcomes. AEX significantly improves aerobic capacity poststroke, but may need to be task specific to affect walking speed and endurance. Higher AEX intensity is associated with better outcomes. Future randomized studies are needed to confirm these results. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Radzol, A R M; Lee, Khuan Y; Mansor, W
2013-01-01
SERS is a form of Raman spectroscopy that is enhanced with nano-sensing chip as substrate. It can yield distinct biochemical fingerprint for molecule of solids, liquids and gases. Vice versa, it can be used to identify unknown molecule. It has further advantage of being non-invasive, non-contact and cheap, as compared to other existing laboratory based techniques. NS1 has been clinically accepted as an alternative biomarker to IgM in diagnosing viral diseases carried by virus of flaviviridae. Its presence in the blood serum at febrile stage of the flavivirus infection has been proven. Being an antigen, it allows early detection that can help to reduce the mortality rate. This paper proposes SERS as a technique for detection of NS1 from its scattering spectrum. Contribution from our work so far has never been reported. From our experiments, it is found that NS1 protein is Raman active. Its spectrum exhibits five prominent peaks at Raman shift of 548, 1012, 1180, 1540 and 1650 cm(-1). Of these, peak at 1012 cm(-1) scales the highest intensity. It is singled out as the peak to fingerprint the NS1 protein. This is because its presence is verified by the ring breathing vibration of the benzene ring structure side chain molecule. The characteristic peak is found to vary in proportion to concentration. It is found that for a 99% change in concentration, a 96.7% change in intensity is incurred. This yields a high sensitivity of about one a.u. per ppm. Further investigation from the characterization graph shows a correlation coefficient of 0.9978 and a standard error estimation of 0.02782, which strongly suggests a linear relationship between the concentration and characteristic peak intensity of NS1. Our finding produces favorable evidence to the use of SERS technique for detection of NS1 protein for early detection of flavivirus infected diseases with gold substrate.
Differential Motor Unit Changes after Endurance or High-Intensity Interval Training.
Martinez-Valdes, Eduardo; Falla, Deborah; Negro, Francesco; Mayer, Frank; Farina, Dario
2017-06-01
Using a novel technique of high-density surface EMG decomposition and motor unit (MU) tracking, we compared changes in the properties of vastus medialis and vastus lateralis MU after endurance (END) and high-intensity interval training (HIIT). Sixteen men were assigned to the END or the HIIT group (n = 8 each) and performed six training sessions for 14 d. Each session consisted of 8-12 × 60-s intervals at 100% peak power output separated by 75 s of recovery (HIIT) or 90-120 min continuous cycling at ~65% V˙O2peak (END). Pre- and postintervention, participants performed 1) incremental cycling to determine V˙O2peak and peak power output and 2) maximal, submaximal (10%, 30%, 50%, and 70% maximum voluntary contraction [MVC]), and sustained (until task failure at 30% MVC) isometric knee extensions while high-density surface EMG signals were recorded from the vastus medialis and vastus lateralis. EMG signals were decomposed (submaximal contractions) into individual MU by convolutive blind source separation. Finally, MU were tracked across sessions by semiblind source separation. After training, END and HIIT improved V˙O2peak similarly (by 5.0% and 6.7%, respectively). The HIIT group showed enhanced maximal knee extension torque by ~7% (P = 0.02) and was accompanied by an increase in discharge rate for high-threshold MU (≥50% knee extension MVC) (P < 0.05). By contrast, the END group increased their time to task failure by ~17% but showed no change in MU discharge rates (P > 0.05). HIIT and END induce different adjustments in MU discharge rate despite similar improvements in cardiopulmonary fitness. Moreover, the changes induced by HIIT are specific for high-threshold MU. For the first time, we show that HIIT and END induce specific neuromuscular adaptations, possibly related to differences in exercise load intensity and training volume.
Neves, Camila D. C.; Lacerda, Ana Cristina Rodrigues; Lage, Vanessa K. S.; Lima, Liliana P.; Fonseca, Sueli F.; de Avelar, Núbia C. P.; Teixeira, Mauro M.; Mendonça, Vanessa A.
2015-01-01
Background The application of the Shuttle Walking Test (SWT) to assess cardiorespiratory fitness and the intensity of this test in healthy participants has rarely been studied. This study aimed to assess and correlate the cardiorespiratory responses of the SWT with the cardiopulmonary exercise testing (CEPT) and to develop a regression equation for the prediction of peak oxygen uptake (VO2 peak) in healthy sedentary adult men. Methods In the first stage of this study, 12 participants underwent the SWT and the CEPT on a treadmill. In the second stage, 53 participants underwent the SWT twice. In both phases, the VO2 peak, respiratory exchange ratio (R), and heart rate (HR) were evaluated. Results Similar results in VO2 peak (P>0.05), R peak (P>0.05) and predicted maximum HR (P>0.05) were obtained between the SWT and CEPT. Both tests showed strong and significant correlations of VO2 peak (r = 0.704, P = 0.01) and R peak (r = 0.737, P<0.01), as well as the agreement of these measurements by Bland-Altman analysis. Body mass index and gait speed were the variables that explained 40.6% (R2 = 0.406, P = 0.001) of the variance in VO2 peak. The results obtained by the equation were compared with the values obtained by the gas analyzer and no significant difference between them (P>0.05) was found. Conclusions The SWT produced maximal cardiorespiratory responses comparable to the CEPT, and the developed equation showed viability for the prediction of VO2 peak in healthy sedentary men. PMID:25659094
Bangert, M; Gil, H; Oliva, J; Delgado, C; Vega, T; DE Mateo, S; Larrauri, A
2017-03-01
The intensity of annual Spanish influenza activity is currently estimated from historical data of the Spanish Influenza Sentinel Surveillance System (SISSS) using qualitative indicators from the European Influenza Surveillance Network. However, these indicators are subjective, based on qualitative comparison with historical data of influenza-like illness rates. This pilot study assesses the implementation of Moving Epidemic Method (MEM) intensity levels during the 2014-2015 influenza season within the 17 sentinel networks covered by SISSS, comparing them to historically reported indicators. Intensity levels reported and those obtained with MEM at the epidemic peak of the influenza wave, and at national and regional levels did not show statistical difference (P = 0·74, Wilcoxon signed-rank test), suggesting that the implementation of MEM would have limited disrupting effects on the dynamic of notification within the surveillance system. MEM allows objective influenza surveillance monitoring and standardization of criteria for comparing the intensity of influenza epidemics in regions in Spain. Following this pilot study, MEM has been adopted to harmonize the reporting of intensity levels of influenza activity in Spain, starting in the 2015-2016 season.
NASA Astrophysics Data System (ADS)
Fan, Tingting; Yuan, Ping; Wang, Xuejuan; Cen, Jianyong; Chang, Xuan; Zhao, Yanyan
2017-09-01
The spectra of two negative cloud-to-ground lightning discharge processes with multi-return strokes are obtained by a slit-less high-speed spectrograph, which the temporal resolution is 110 μs. Combined with the synchronous electrical observation data and theoretical calculation, the physical characteristics during return strokes process are analysed. A positive correlation between discharge current and intensity of ionic lines in the spectra is verified, and based on this feature, the current evolution characteristics during four return strokes are investigated. The results show that the time from peak current to the half-peak value estimated by multi point-fitting is about 101 μs-139 μs. The Joule heat in per unit length of four return strokes channel is in the order of 105J/m-106 J/m. The radius of arc discharge channel is positively related to the discharge current, and the more intense the current is, the greater the radius of channel is. Furthermore, the evolution for radius of arc core channel in the process of return stroke is consistent with the change trend of discharge current after the peak value. Compared with the decay of the current, the temperature decreases more slowly.
Dosimetric characteristics of LKB:Cu,P solid TL detector
NASA Astrophysics Data System (ADS)
Hashim, S.; Alajerami, Y. S. M.; Ghoshal, S. K.; Saleh, M. A.; Saripan, M. I.; Kadir, A. B. A.; Bradley, D. A.; Alzimami, K.
2014-11-01
The dosimetric characteristics of newly developed borate glass dosimeter modified with lithium and potassium carbonate (LKB) and co-doped with CuO and NH4H2PO4 are reported. Broad peaks in the absence of any sharp peak confirms the amorphous nature of the prepared glass. A simple glow curve of Cu doped sample is observed with a single prominent peak (Tm) at 220 °C. The TL intensity response shows an enhancement of ~100 times due to the addition of CuO (0.1 mol%) to LKB compound. A further enhancement of the intensity by a factor of 3 from the addition of 0.25 mol% NH4H2PO4 as a co-dopant impurity is attributed to the creation of extra electron traps with consequent increase in energy transfer of radiation recombination centers. The TL yield performance of LKB:Cu,P with Zeff ≈8.92 is approximately seventeen times less sensitive compared to LiF:Mg,Ti (TLD-100). The proposed dosimeter shows good linearity up to 103 Gy, minimal fading and photon energy independence. These attractive features offered by our dosimeter is expected to pave the way towards dosimetric applications.
NASA Astrophysics Data System (ADS)
Lin, Guangyang; Yi, Xiaohui; Li, Cheng; Chen, Ningli; Zhang, Lu; Chen, Songyan; Huang, Wei; Wang, Jianyuan; Xiong, Xihuan; Sun, Jiaming
2016-10-01
A lateral p-Si0.05Ge0.95/i-Ge/n-Si0.05Ge0.95 heterojunction light emitting diode on a silicon-on-insulator (SOI) substrate was proposed, which is profitable to achieve higher luminous extraction compared to vertical junctions. Due to the high carrier injection ratio of heterostructures and optical reflection at the SiO2/Si interface of the SOI, strong room temperature electroluminescence (EL) at around 1600 nm from the direct bandgap of i-Ge with 0.30% tensile strain was observed. The EL peak intensity of the lateral heterojunction is enhanced by ˜4 folds with a larger peak energy than that of the vertical Ge p-i-n homojunction, suggesting that the light emitting efficiency of the lateral heterojunction is effectively improved. The EL peak intensity of the lateral heterojunction, which increases quadratically with injection current density, becomes stronger for diodes with a wider i-Ge region. The CMOS compatible fabrication process of the lateral heterojunctions paves the way for the integration of the light source with the Ge metal-oxide-semiconductor field-effect-transistor.
Peak picking NMR spectral data using non-negative matrix factorization.
Tikole, Suhas; Jaravine, Victor; Rogov, Vladimir; Dötsch, Volker; Güntert, Peter
2014-02-11
Simple peak-picking algorithms, such as those based on lineshape fitting, perform well when peaks are completely resolved in multidimensional NMR spectra, but often produce wrong intensities and frequencies for overlapping peak clusters. For example, NOESY-type spectra have considerable overlaps leading to significant peak-picking intensity errors, which can result in erroneous structural restraints. Precise frequencies are critical for unambiguous resonance assignments. To alleviate this problem, a more sophisticated peaks decomposition algorithm, based on non-negative matrix factorization (NMF), was developed. We produce peak shapes from Fourier-transformed NMR spectra. Apart from its main goal of deriving components from spectra and producing peak lists automatically, the NMF approach can also be applied if the positions of some peaks are known a priori, e.g. from consistently referenced spectral dimensions of other experiments. Application of the NMF algorithm to a three-dimensional peak list of the 23 kDa bi-domain section of the RcsD protein (RcsD-ABL-HPt, residues 688-890) as well as to synthetic HSQC data shows that peaks can be picked accurately also in spectral regions with strong overlap.
Stott, Rebecca; Davies-Colley, Robert; Nagels, John; Donnison, Andrea; Ross, Colleen; Muirhead, Richard
2011-03-01
The faecal indicator bacterium Escherichia coli and thermotolerant Campylobacter spp., which are potentially pathogenic, were investigated in the Toenepi Stream draining a pastoral catchment dominated by dairying. Bacteria concentrations were monitored routinely at fortnightly intervals over 12 months and intensively during storm events to compare the transport dynamics of bacterial indicator and pathogen under varying hydro-meteorological conditions. Routine monitoring indicated median concentrations of 345 E. coli MPN 100 ml(-1) and relatively low concentrations of 2.3 Campylobacter MPN 100 ml(-1). The bacterial flux was three orders of magnitude greater under elevated stream flow compared with base-flow. E. coli peak concentrations occurred very close to the turbidity peak and consistently ahead of the Campylobacter spp. peak (which was close to the hydrograph peak). We postulate that, under flood conditions, the E. coli peak reflects the entrainment and mobilisation of in-stream stores on the flood wave front. In contrast, Campylobacter spp. are derived from wash-in from land stores upstream and have travelled at the mean water velocity which is slower than the speed of the flood wave. Our findings of different dynamics for E. coli and Campylobacter spp. suggest that mitigation to reduce faecal microbial impacts from farms will need to take account of these differences.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gupta, S. B.; Bihari, B.; Biruduganti, M.
Flame chemiluminescence is widely acknowledged to be an indicator of heat release rate in premixed turbulent flames that are representative of gas turbine combustion. Though heat release rate is an important metric for evaluating combustion strategies in reciprocating engine systems, its correlation with flame chemiluminescence is not well studied. To address this gap an experimental study was carried out in a single-cylinder natural gas fired reciprocating engine that could simulate turbocharged conditions with exhaust gas recirculation. Crank angle resolved spectra (266-795 nm) of flame luminosity were measured for various operational conditions by varying the ignition timing for MBT conditions andmore » by holding the speed at 1800 rpm and Brake Mean effective Pressure (BMEP) at 12 bar. The effect of dilution on CO*{sub 2}chemiluminescence intensities was studied, by varying the global equivalence ratio (0.6-1.0) and by varying the exhaust gas recirculation rate. It was attempted to relate the measured chemiluminescence intensities to thermodynamic metrics of importance to engine research -- in-cylinder bulk gas temperature and heat release rate (HRR) calculated from measured cylinder pressure signals. The peak of the measured CO*{sub 2} chemiluminescence intensities coincided with peak pressures within {+-}2 CAD for all test conditions. For each combustion cycle, the peaks of heat release rate, spectral intensity and temperature occurred in that sequence, well separated temporally. The peak heat release rates preceded the peak chemiluminescent emissions by 3.8-9.5 CAD, whereas the peak temperatures trailed by 5.8-15.6 CAD. Such a temporal separation precludes correlations on a crank-angle resolved basis. However, the peak cycle heat release rates and to a lesser extent the peak cycle temperatures correlated well with the chemiluminescent emission from CO*{sub 2}. Such observations point towards the potential use of flame chemiluminescence to monitor peak bulk gas temperatures as well as peak heat release rates in natural gas fired reciprocating engines.« less
Kim, Young-sun; Kim, Byoung-Gie; Rhim, Hyunchul; Bae, Duk-Soo; Lee, Jeong-Won; Kim, Tae-Joong; Choi, Chel Hun; Lee, Yoo-Young; Lim, Hyo Keun
2014-11-01
To determine whether semiquantitative perfusion magnetic resonance (MR) imaging parameters are associated with therapeutic effectiveness of MR imaging-guided high-intensity focused ultrasound ( HIFU high-intensity focused ultrasound ) ablation of uterine fibroids and which semiquantitative perfusion parameters are significant with regard to treatment efficiency. This study was approved by the institutional review board, and informed consent was obtained from all subjects. Seventy-seven women (mean age, 43.3 years) with 119 fibroids (mean diameter, 7.5 cm) treated with MR imaging-guided HIFU high-intensity focused ultrasound ablation were analyzed. The correlation between semiquantitative perfusion MR parameters (peak enhancement, relative peak enhancement, time to peak, wash-in rate, washout rate) and heating and ablation efficiencies (lethal thermal dose volume based on MR thermometry and nonperfused volume based on immediate contrast-enhanced image divided by intended treatment volume) were evaluated by using a linear mixed model on a per-fibroid basis. The specific value of the significant parameter that had a substantial effect on treatment efficiency was determined. The mean peak enhancement, relative peak enhancement, time to peak, wash-in rate, and washout rate of the fibroids were 1293.1 ± 472.8 (range, 570.2-2477.8), 171.4% ± 57.2 (range, 0.6%-370.2%), 137.2 seconds ± 119.8 (range, 20.0-300.0 seconds), 79.5 per second ± 48.2 (range, 12.5-236.7 per second), and 11.4 per second ± 10.1 (range, 0-39.3 per second), respectively. Relative peak enhancement was found to be independently significant for both heating and ablation efficiencies (B = -0.002, P < .001 and B = -0.003, P = .050, respectively). The washout rate was significantly associated with ablation efficiency (B = -0.018, P = .043). Both efficiencies showed the most abrupt transitions at 220% of relative peak enhancement. Relative peak enhancement at semiquantitative perfusion MR imaging was significantly associated with treatment efficiency of MR imaging-guided HIFU high-intensity focused ultrasound ablation of uterine fibroids, and a value of 220% or less is suggested as a screening guideline for more efficient treatment.
The effects of γ-ray on charging behaviour using polyimide
NASA Astrophysics Data System (ADS)
Qin, Sichen; Tu, Youping; Tan, Tian; Wang, Shaohe; Yuan, Zhikang; Wang, Cong; Li, Laifeng; Wu, Zhixiong
2018-06-01
Insulation material is a key component of electrical equipment in satellites; its electrical properties determine the reliability and lifetime of the whole satellite. High-energy radioactive rays in space affect the molecular structure of the polymeric insulating materials. Under the action of plasma, high energy particles, along with the magnetic fields experienced in orbits, electric charges get injected into and trapped by the insulating material creating distortions in the electric field and even electrostatic discharges. Polyimides have been widely used for insulation in spacecraft. Choosing Co-60 gamma ray with irradiation doses of 1 MGy and 5 MGy to simulate the radiation environment of space, we investigated the effect of radiation on charging behaviour. The thermal stimulated current (TSC) from a high electric field over a wide range of temperatures was measured from which the activation energy was calculated. These results for the two sources show that the percentage increase in total charge was 133.3% and 119.4%. The γ, β 3, and α charge peaks of specimens after an irradiation dose of 1 MGy rose. In comparison, the β 2 peak of the 5 MGy-dosed specimens was enhanced. Also, there is almost no change in the γ, β 3, and α peaks. To understand the mechanism behind the TSC changes, the resulting physicochemical characteristics of an irradiated specimen were observed employing various analyses of chemical characteristics (x-ray photoelectron spectroscopy, differential scanning calorimetry and x-ray diffraction). Compared with the non-dosed specimen, the relative content of C–N and the glass transition temperature of the 1 MGy sample decreased, and the crystallinity increased, thus increasing the γ and α peak intensities. Compared with the 1 MGy sample, only the glass transition temperature had risen, thereby enhancing the β peak intensity. With the foregoing, a theoretical base for the selection and modification of insulation materials for spacecraft is provided.
Paolini, A G; Clark, G M
1999-05-01
Intracellular responses of onset chopper neurons in the ventral cochlear nucleus to tones: evidence for dual-component processing. The ventral cochlear nucleus (VCN) contains a heterogeneous collection of cell types reflecting the multiple processing tasks undertaken by this nucleus. This in vivo study in the rat used intracellular recordings and dye filling to examine membrane potential changes and firing characteristics of onset chopper (OC) neurons to acoustic stimulation (50 ms pure tones, 5 ms r/f time). Stable impalements were made from 15 OC neurons, 7 identified as multipolar cells. Neurons responded to characteristic frequency (CF) tones with sustained depolarization below spike threshold. With increasing stimulus intensity, the depolarization during the initial 10 ms of the response became peaked, and with further increases in intensity the peak became narrower. Onset spikes were generated during this initial depolarization. Tones presented below CF resulted in a broadening of this initial depolarizing component with high stimulus intensities required to initiate onset spikes. This initial component was followed by a sustained depolarizing component lasting until stimulus cessation. The amplitude of the sustained depolarizing component was greatest when frequencies were presented at high intensities below CF resulting in increased action potential firing during this period when compared with comparable high intensities at CF. During the presentation of tones at or above the high-frequency edge of a cell's response area, hyperpolarization was evident during the sustained component. The presence of hyperpolarization and the differences seen in the level of sustained depolarization during CF and off CF tones suggests that changes in membrane responsiveness between the initial and sustained components may be attributed to polysynaptic inhibitory mechanisms. The dual-component processing resulting from convergent auditory nerve excitation and polysynaptic inhibition enables OC neurons to respond in a unique fashion to intensity and frequency features contained within an acoustic stimulus.
Turner, D; Gray, B J; Luzio, S; Dunseath, G; Bain, S C; Hanley, S; Richards, A; Rhydderch, D C; Ayles, M; Kilduff, L P; Campbell, M D; West, D J; Bracken, R M
2016-04-01
The aim of this study was to compare the glycemic and glucoregulatory hormone responses to low- and moderate-intensity morning resistance exercise (RE) sessions in type 1 diabetes (T1DM). Following maximal strength assessments (1RM), eight T1DM (HbA1C :72 ± 12 mmol/mol, age:34 ± 7 years, body mass index:25.7 ± 1.6 kg/m(2) ) participants attended the research facility on two separate occasions, having fasted and taken their usual basal insulin but omitting rapid-acting insulin. Participants performed six exercises for two sets of 20 repetitions at 30%1RM during one session [low-intensity RE session (LOW)] and two sets of 10 repetitions at 60%1RM during another session [moderate-intensity RE session (MOD)], followed by 65-min recovery. Sessions were matched for total mass lifted (kg). Venous blood samples were taken before and after exercise. Data (mean ± SEM) were analyzed using analysis of variance (P ≤ 0.05). There were no hypoglycemic occurrences throughout the study. Blood glucose rose similarly between sessions during exercise (P = 0.382), remaining comparable between sessions throughout recovery (P > 0.05). There was no effect of RE intensity on metabolic acidosis (P > 0.05) or peak growth hormone responses (P = 0.644), but a tendency for greater catecholamine responses under LOW (individualized peak concentrations: adrenaline MOD 0.55 ± 0.13 vs LOW 1.04 ± 0.37 nmol/L, P = 0.155; noradrenaline MOD 4.59 ± 0.86 vs LOW 7.11 ± 1.82 nmol/L, P = 0.082). The magnitude of post-exercise hyperglycemia does not differ between equal volume low and moderate intensity RE sessions performed in the morning. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
CdSe/ZnS quantum dot fluorescence spectra shape-based thermometry via neural network reconstruction
DOE Office of Scientific and Technical Information (OSTI.GOV)
Munro, Troy; Laboratory of Soft Matter and Biophysics, Department of Physics and Astronomy, KU Leuven, Celestijnenlaan 200D, B-3001 Heverlee; Liu, Liwang
As a system of interest gets small, due to the influence of the sensor mass and heat leaks through the sensor contacts, thermal characterization by means of contact temperature measurements becomes cumbersome. Non-contact temperature measurement offers a suitable alternative, provided a reliable relationship between the temperature and the detected signal is available. In this work, exploiting the temperature dependence of their fluorescence spectrum, the use of quantum dots as thermomarkers on the surface of a fiber of interest is demonstrated. The performance is assessed of a series of neural networks that use different spectral shape characteristics as inputs (peak-based—peak intensity,more » peak wavelength; shape-based—integrated intensity, their ratio, full-width half maximum, peak normalized intensity at certain wavelengths, and summation of intensity over several spectral bands) and that yield at their output the fiber temperature in the optically probed area on a spider silk fiber. Starting from neural networks trained on fluorescence spectra acquired in steady state temperature conditions, numerical simulations are performed to assess the quality of the reconstruction of dynamical temperature changes that are photothermally induced by illuminating the fiber with periodically intensity-modulated light. Comparison of the five neural networks investigated to multiple types of curve fits showed that using neural networks trained on a combination of the spectral characteristics improves the accuracy over use of a single independent input, with the greatest accuracy observed for inputs that included both intensity-based measurements (peak intensity) and shape-based measurements (normalized intensity at multiple wavelengths), with an ultimate accuracy of 0.29 K via numerical simulation based on experimental observations. The implications are that quantum dots can be used as a more stable and accurate fluorescence thermometer for solid materials and that use of neural networks for temperature reconstruction improves the accuracy of the measurement.« less
Yardley, Marianne; Gullestad, Lars; Bendz, Bjørn; Bjørkelund, Elisabeth; Rolid, Katrine; Arora, Satish; Nytrøen, Kari
2017-01-01
Previous studies have demonstrated that high-intensity interval training (HIT) is superior to moderate-continuous exercise in general and in cardiovascular diseases. Recently, we also found HIT safe and efficient after heart transplantation (HTx). This study reports the 5-year long-term effects. Forty-one HTx patients who had completed the previous 12-month randomized controlled trial, comparing HIT intervention with usual care, were eligible. In particular, we measured VO 2peak , muscular capacity, intravascular ultrasound, and questionnaires measuring physical and mental health. The baseline mean±SD values were as follows: age; 49.1±16.5 years, men; 68%, time since HTx: 4.1±2.2 years. Within the HIT group, initial VO 2peak increased significantly from 27.7±5.7 to 31.2±5.3 mL/kg/min. However, during the next 4 years, VO 2peak decreased to 26.0±6.2 mL/kg/min. The control group showed slightly decreasing VO 2peak values during the entire 5-year period. The HIT group reported significantly less anxiety symptoms, but there were no long-term differences in VO 2peak , muscular capacity, or cardiac allograft vasculopathy between the groups. The similar VO 2peak values correspond to our findings of similar everyday activity. Our findings suggest that intermittent periods of HIT may be necessary to maintain the initial benefits gained from the intervention. However, HIT probably reduces the burden of anxiety, which is a frequent health issue following HTx. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Bailey, Tom G; Perissiou, Maria; Windsor, Mark; Russell, Fraser; Golledge, Jonathan; Green, Daniel J; Askew, Christopher D
2017-05-01
Impaired endothelial function is observed with aging and in those with low cardiorespiratory fitness (V̇o 2peak ). Improvements in endothelial function with exercise training are somewhat dependent on the intensity of exercise. While the acute stimulus for this improvement is not completely understood, it may, in part, be due to the flow-mediated dilation (FMD) response to acute exercise. We examined the hypothesis that exercise intensity alters the brachial (systemic) FMD response in elderly men and is modulated by V̇o 2peak Forty-seven elderly men were stratified into lower (V̇o 2peak = 24.3 ± 2.9 ml·kg -1 ·min -1 ; n = 27) and higher fit groups (V̇o 2peak = 35.4 ± 5.5 ml·kg -1 ·min -1 ; n = 20) after a test of cycling peak power output (PPO). In randomized order, participants undertook moderate-intensity continuous exercise (MICE; 40% PPO) or high-intensity interval cycling exercise (HIIE; 70% PPO) or no-exercise control. Brachial FMD was assessed at rest and 10 and 60 min after exercise. FMD increased after MICE in both groups {increase of 0.86% [95% confidence interval (CI), 0.17-1.56], P = 0.01} and normalized after 60 min. In the lower fit group, FMD was reduced after HIIE [reduction of 0.85% (95% CI, 0.12-1.58), P = 0.02] and remained decreased at 60 min. In the higher fit group, FMD was unchanged immediately after HIIE and increased after 60 min [increase of 1.52% (95% CI, 0.41-2.62), P < 0.01, which was correlated with V̇o 2peak , r = 0.41; P < 0.01]. In the no-exercise control, FMD was reduced in both groups after 60 min ( P = 0.05). Exercise intensity alters the acute FMD response in elderly men and V̇o 2peak modulates the FMD response following HIIE but not MICE. The sustained decrease in FMD in the lower fit group following HIIE may represent a signal for vascular adaptation or endothelial fatigue. NEW & NOTEWORTHY This study is the first to show that moderate-intensity continuous cycling exercise increased flow-mediated dilation (FMD) transiently before normalization of FMD after 1 h, irrespective of cardiorespiratory fitness level in elderly men. Interestingly, we show increased FMD after high-intensity cycling exercise in higher fit men, with a sustained reduction in FMD in lower fit men. The prolonged reduction in FMD after high-intensity cycling exercise may be associated with future vascular adaptation but may also reflect a period of increased cardiovascular risk in lower fit elderly men. Copyright © 2017 the American Physiological Society.
Validity of Various Methods for Determining Velocity, Force, and Power in the Back Squat.
Banyard, Harry G; Nosaka, Ken; Sato, Kimitake; Haff, G Gregory
2017-10-01
To examine the validity of 2 kinematic systems for assessing mean velocity (MV), peak velocity (PV), mean force (MF), peak force (PF), mean power (MP), and peak power (PP) during the full-depth free-weight back squat performed with maximal concentric effort. Ten strength-trained men (26.1 ± 3.0 y, 1.81 ± 0.07 m, 82.0 ± 10.6 kg) performed three 1-repetition-maximum (1RM) trials on 3 separate days, encompassing lifts performed at 6 relative intensities including 20%, 40%, 60%, 80%, 90%, and 100% of 1RM. Each repetition was simultaneously recorded by a PUSH band and commercial linear position transducer (LPT) (GymAware [GYM]) and compared with measurements collected by a laboratory-based testing device consisting of 4 LPTs and a force plate. Trials 2 and 3 were used for validity analyses. Combining all 120 repetitions indicated that the GYM was highly valid for assessing all criterion variables while the PUSH was only highly valid for estimations of PF (r = .94, CV = 5.4%, ES = 0.28, SEE = 135.5 N). At each relative intensity, the GYM was highly valid for assessing all criterion variables except for PP at 20% (ES = 0.81) and 40% (ES = 0.67) of 1RM. Moreover, the PUSH was only able to accurately estimate PF across all relative intensities (r = .92-.98, CV = 4.0-8.3%, ES = 0.04-0.26, SEE = 79.8-213.1 N). PUSH accuracy for determining MV, PV, MF, MP, and PP across all 6 relative intensities was questionable for the back squat, yet the GYM was highly valid at assessing all criterion variables, with some caution given to estimations of MP and PP performed at lighter loads.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ebert, R. W.; Dayeh, M. A.; Desai, M. I.
2016-11-10
We examine the longitude distribution of and relationship between interplanetary (IP) shock properties and ∼0.1–20 MeV nucleon{sup -1} O and Fe ions during seven multi-spacecraft energetic storm particle (ESP) events at 1 au. These ESP events were observed at two spacecraft and were primarily associated with low Mach number, quasi-perpendicular shocks. Key observations include the following: (i) the Alfvén Mach number increased from east to west of the coronal mass ejection source longitude, while the shock speed, compression ratios, and obliquity showed no clear dependence; (ii) the O and Fe time intensity profiles and peak intensities varied significantly between longitudinallymore » separated spacecraft observing the same event, the peak intensities being larger near the nose and smaller along the flank of the IP shock; (iii) the O and Fe peak intensities had weak to no correlations with the shock parameters; (iv) the Fe/O time profiles showed intra-event variations upstream of the shock that disappeared downstream of the shock, where values plateaued to those comparable to the mean Fe/O of solar cycle 23; (v) the O and Fe spectral index ranged from ∼1.0 to 3.4, the Fe spectra being softer in most events; and (vi) the observed spectral index was softer than the value predicted from the shock compression ratio in most events. We conclude that while the variations in IP shock properties may account for some variations in O and Fe properties within these multi-spacecraft events, detailed examination of the upstream seed population and IP turbulence, along with modeling, are required to fully characterize these observations.« less
Ramos, Joyce S; Dalleck, Lance C; Tjonna, Arnt Erik; Beetham, Kassia S; Coombes, Jeff S
2015-05-01
Vascular dysfunction is a precursor to the atherosclerotic cascade, significantly increasing susceptibility to cardiovascular events such as myocardial infarction or stroke. Previous studies have revealed a strong relationship between vascular function and cardiorespiratory fitness (CRF). Thus, since high-intensity interval training (HIIT) is a potent method of improving CRF, several small randomized trials have investigated the impact on vascular function of HIIT relative to moderate-intensity continuous training (MICT). The aim of this study was to systematically review the evidence and quantify the impact on vascular function of HIIT compared with MICT. Three electronic databases (PubMed, Embase, and MEDLINE) were searched (until May 2014) for randomized trials comparing the effect of at least 2 weeks of HIIT and MICT on vascular function. HIIT protocols involved predominantly aerobic exercise at a high intensity, interspersed with active or passive recovery periods. We performed a meta-analysis to compare the mean difference in the change in vascular function assessed via brachial artery flow-mediated dilation (FMD) from baseline to post-intervention between HIIT and MICT. The impact of HIIT versus MICT on CRF, traditional cardiovascular disease (CVD) risk factors, and biomarkers associated with vascular function (oxidative stress, inflammation, and insulin resistance) was also reviewed across included studies. Seven randomized trials, including 182 patients, met the eligibility criteria and were included in the meta-analysis. A commonly used HIIT prescription was four intervals of 4 min (4 × 4 HIIT) at 85-95% of maximum or peak heart rate (HRmax/peak), interspersed with 3 min of active recovery at 60-70% HRmax/peak, three times per week for 12-16 weeks. Brachial artery FMD improved by 4.31 and 2.15% following HIIT and MICT, respectively. This resulted in a significant (p < 0.05) mean difference of 2.26%. HIIT also had a greater tendency than MICT to induce positive effects on secondary outcome measures, including CRF, traditional CVD risk factors, oxidative stress, inflammation, and insulin sensitivity. HIIT is more effective at improving brachial artery vascular function than MICT, perhaps due to its tendency to positively influence CRF, traditional CVD risk factors, oxidative stress, inflammation, and insulin sensitivity. However, the variability in the secondary outcome measures, coupled with the small sample sizes in these studies, limits this finding. Nonetheless, this review suggests that 4 × 4 HIIT, three times per week for at least 12 weeks, is a powerful form of exercise to enhance vascular function.
Ahmadizad, Sajad; Nouri-Habashi, Akbar; Rahmani, Hiwa; Maleki, Majid; Naderi, Nasim; Lotfian, Sara; Salimian, Morteza
2016-01-01
The effects of high intensity interval training (HIIT) on inflammatory markers and endothelial function have been extensively shown. However, the acute effect of HIIT on platelet activation and function in patients with recent revascularization is unclear. The purpose of present study was to compare the responses of platelet activation (CD62P) and function (platelet aggregation) to high intensity interval exercise (HIIE) and moderate continuous exercise (MCE) in coronary artery bypass grafting (CABG) and percutaneous coronary interventions (PCI) patients. Thirty patients who had CABG or PCI were randomly divided into HIIE, MCE and control groups. After determining the VO2peak, subjects in the MCE group carried out 30 min of continuous exercise at 60% of VO2peak, whereas, the subjects in HIIE group performed an interval protocol consisted of 8 repetitions of 2 min activity (running on treadmill) at 90% of VO2peak interspersed by 2 min of active recovery between repetitions at 30% of VO2peak . Subjects in control group were seated and had no activity for the same period of time. Two blood samples were collected before and immediately after exercise and were analyzed for markers of platelet activation and function. Data analyzes revealed that increases in platelet aggregation induced by ADP and corrected for increases in platelet count in response to MCE trial was significantly lower than HIIE group (P < 0.05). In addition, responses of CD62P to MCE trial was significantly lower compared to HIIE group (P < 0.05). Changes in plateletcrit and platelet distribution width were significantly different among the three trials where the PCT and PDW following the HIIE were higher than MCE. Platelet count increased significantly (P < 0.05) by 13% following HIIE trial. Based on the findings of the present study it could be concluded that the risk of exercise-induced thrombosis is higher during HIIE than MCE in patients with recent revascularization.
NASA Astrophysics Data System (ADS)
Phillips, R. C.; Samadi, S. Z.; Meadows, M. E.
2018-07-01
This paper examines the frequency, distribution tails, and peak-over-threshold (POT) of extreme floods through analysis that centers on the October 2015 flooding in North Carolina (NC) and South Carolina (SC), United States (US). The most striking features of the October 2015 flooding were a short time to peak (Tp) and a multi-hour continuous flood peak which caused intensive and widespread damages to human lives, properties, and infrastructure. The 2015 flooding was produced by a sequence of intense rainfall events which originated from category 4 hurricane Joaquin over a period of four days. Here, the probability distribution and distribution parameters (i.e., location, scale, and shape) of floods were investigated by comparing the upper part of empirical distributions of the annual maximum flood (AMF) and POT with light- to heavy- theoretical tails: Fréchet, Pareto, Gumbel, Weibull, Beta, and Exponential. Specifically, four sets of U.S. Geological Survey (USGS) gauging data from the central Carolinas with record lengths from approximately 65-125 years were used. Analysis suggests that heavier-tailed distributions are in better agreement with the POT and somewhat AMF data than more often used exponential (light) tailed probability distributions. Further, the threshold selection and record length affect the heaviness of the tail and fluctuations of the parent distributions. The shape parameter and its evolution in the period of record play a critical and poorly understood role in determining the scaling of flood response to intense rainfall.
[Study of alkaline lignin from Arundo donax linn based on FT Raman spectroscopy].
You, Ting-ting; Ma, Jian-feng; Guo, Si-qin; Xu, Feng
2014-08-01
Arundo donax linn, as a perennial energy crop, has promising application prospect. In the present study, Fourier transform Raman (FT Raman) spectroscopy was applied to determine the structural information of materials, milled wood lignin (MWL), and alkaline lignins (AL, under different treated time) from A. donax stem nondestructively. The results indicated that, extractable compounds in A. donax had negative contribution to the Raman spectra without rising new Raman peaks. FT Raman spectrum of MWL indicated that MWL from A. donax was HGS type lignins. Compared with the spectra of MWL from wood materials, the peak at 1173 cm(-1) was much higher in intensity for the MWL from A. donax stem, which may be assigned to hydroxycinnamic acid by analyzing the standard. With respect to FT Raman spectra of ALs, the relatively highest intensity of 1173 cm(-1) was found in alkaline lignin (AL2), which was treated for 40 min by alkaline. Moreover, the peak of coniferaldehyde/sinapaldehyde (1630 cm(-1)) was lowest in intensity while the band attributed to coniferyl alcohol/sinapyl alcohol (1660 cm(-1)) was almost disappeared in AL2. It could be inferred that AL2 demonstrated a highest content of phenolic acid, which may improve its potential application, such as for antioxidant activity. Furthermore, the results obtained by FT Raman spectra were verified by two dimensional heteronuclear singlequantum coherence nuclear magnetic resonance analyses. Above all, FT Raman spectroscopy provided alternative safe, rapid, accurate, and nondestructive technology for lignin structure determination.
Acoustic analysis of oropharyngeal swallowing using Sonar Doppler.
Soria, Franciele Savaris; Silva, Roberta Gonçalves da; Furkim, Ana Maria
2016-01-01
During the aging process, one of the functions that changes is swallowing. These alterations in oropharyngeal swallowing may be diagnosed by methods that allow both the diagnosis and biofeedback monitoring by the patient. One of the methods recently described in the literature for the evaluation of swallowing is the Sonar Doppler. To compare the acoustic parameters of oropharyngeal swallowing between different age groups. This was a field, quantitative, study. Examination with Sonar Doppler was performed in 75 elderly and 72 non-elderly adult subjects. The following acoustic parameters were established: initial frequency, first peak frequency, second peak frequency; initial intensity, final intensity; and time for the swallowing of saliva, liquid, nectar, honey, and pudding, with 5- and 10-mL free drinks. Objective, measurable data were obtained; most acoustic parameters studied between adult and elderly groups with respect to consistency and volume were significant. When comparing elderly with non-elderly adult subjects, there is a modification of the acoustic pattern of swallowing, regarding both consistency and food bolus volume. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.
Zinner, Christoph; Sperlich, Billy; Born, Dennis-Peter; Michels, Guido
2017-01-01
The purpose of this study was to investigate the effects of combined arm and leg high-intensity low-volume interval training (HIITarm+leg) on maximal oxygen uptake, myocardial measures (i.e. stroke volume, cardiac output, ejection fraction), Tissue Oxygenation Index (TOI) of the vastus lateralis and triceps brachii, as well as power output in comparison to leg HIIT (HIITleg) only. The 20 healthy, male and female volunteers completed six sessions of either HIITleg on a cycle ergometer or HIITarm+leg on an arm and leg cycle ergometer. During pre- and post-testing, the volunteers completed a submaximal and incremental test to exhaustion on a cycle ergometer. Magnitude based interference revealed likely to very likely beneficial effects for HIITarm+leg compared to HIITleg in maximal oxygen uptake, cardiac measures as well peak power output. The TOI following HIITarm+leg demonstrated likely to very likely increased oxygenation in the triceps brachii or the vastus lateralis when compared to HIITleg. The results suggest that six sessions of HIITarm+leg may likely to very likely improve maximal oxygen uptake, some inotropy-related cardiac measures with improved tissue oxygenation of the triceps brachii and vastus lateralis muscles resulting in greater leg peak power output.
The 6300 A O/1-D/ airglow and dissociative recombination
NASA Technical Reports Server (NTRS)
Wickwar, V. B.; Cogger, L. L.; Carlson, H. C.
1974-01-01
Measurements of night-time 6300 A airglow intensities at the Arecibo Observatory have been compared with dissociative recombination calculations based on electron densities derived from simultaneous incoherent backscatter measurements. The agreement indicates that the nightglow can be fully accounted for by dissociative recombination. The comparisons are examined to determine the importance of quenching, heavy ions, ionization above the F-layer peak, and the temperature parameter of the model atmosphere. Comparable fits between the observed and calculated intensities are found for several available model atmospheres. The least-squares fitting process, used to make the comparisons, produces comparable fits over a wide range of combinations of neutral densities and of reaction constants. Yet, the fitting places constraints upon the possible combinations; these constraints indicate that the latest laboratory chemical constants and densities extrapolated to a base altitude are mutually consistent.
Contrast-enhanced ultrasonography for the evaluation of liver fibrosis after biliary obstruction.
Shin, Hyun Joo; Chang, Eun Young; Lee, Hye Sun; Hong, Jung Hwa; Park, Gyuri; Kim, Hyun Gi; Kim, Myung-Joon; Lee, Mi-Jung
2015-03-07
To investigate perfusion change in contrast-enhanced ultrasonography (CEUS) to evaluate liver fibrosis based on biliary obstruction using an animal model. New Zealand white rabbits (3-4 kg) underwent bile duct ligation to form a biliary obstruction model. We performed liver CEUS and laboratory tests on the day before the operation (day 0) and every 7 postoperative days until the rabbits were sacrificed. After CEUS, signal intensity of liver parenchyma with a time-intensity curve was analyzed. Perfusion parameters were automatically calculated from region-of-interests, including peak signal intensity, mean transit time, area under the curve and time to peak. Histological grades of liver fibrosis were assessed according to the Metavir score system immediately after sacrifice. Generalized estimating equations were used to analyze the association between liver fibrosis grades and perfusion parameters for statistical analysis. The perfusion parameters were measured on the last day and the difference between day 0 and the last day were evaluated. From the nine rabbits, histological grades of liver fibrosis were grade 1 in one rabbit, grade 2 and 3 in three rabbits each, and grade 4 in two rabbits. Among the four CEUS parameters, only the peak signal intensity measured on the last day demonstrated a significant association with liver fibrosis grades (OR = 1.392, 95%CI: 1.114-1.741, P = 0.004). The difference in peak signal intensity between day 0 and the last day also demonstrated an association with liver fibrosis (OR = 1.191, 95%CI: 0.999-1.419, P = 0.051). The other parameters tested, including mean transit time, area under the curve, and time to peak, showed no significant correlation with liver fibrosis grades. This animal study demonstrates that CEUS can be used to evaluate liver fibrosis from biliary obstruction using peak signal intensity as a parameter.
NASA Astrophysics Data System (ADS)
Zhang, W. L.; Qiao, B.; Shen, X. F.; You, W. Y.; Huang, T. W.; Yan, X. Q.; Wu, S. Z.; Zhou, C. T.; He, X. T.
2016-09-01
Laser-driven ion acceleration potentially offers a compact, cost-effective alternative to conventional accelerators for scientific, technological, and health-care applications. A novel scheme for heavy ion acceleration in near-critical plasmas via staged shock waves driven by intense laser pulses is proposed, where, in front of the heavy ion target, a light ion layer is used for launching a high-speed electrostatic shock wave. This shock is enhanced at the interface before it is transmitted into the heavy ion plasmas. Monoenergetic heavy ion beam with much higher energy can be generated by the transmitted shock, comparing to the shock wave acceleration in pure heavy ion target. Two-dimensional particle-in-cell simulations show that quasi-monoenergetic {{{C}}}6+ ion beams with peak energy 168 MeV and considerable particle number 2.1 × {10}11 are obtained by laser pulses at intensity of 1.66 × {10}20 {{W}} {{cm}}-2 in such staged shock wave acceleration scheme. Similarly a high-quality {{Al}}10+ ion beam with a well-defined peak with energy 250 MeV and spread δ E/{E}0=30 % can also be obtained in this scheme.
Wave Phenomena Associated with Interplanetary Shocks
NASA Astrophysics Data System (ADS)
Golla, T.; MacDowall, R. J.
2016-12-01
Although laboratory and space-based experiments were used for the last several decades to study the collisionless shocks, several questions remain less than fully understood. These include: (1) what type of wave-particle energy dissipation is responsible for the shock formation, (2) what type of in-situ waves occur in the upstream, transition and downstream regions, and (3) which physical processes are responsible for the excitation of the fundamental and second harmonic solar type II radio emissions. In this study, we will address these issues using (1) the in situ and radio wave data obtained by the WAVES experiments of the STEREO A and B, and WIND spacecraft, especially the high time resolution data from the time domain samplers (TDS) of these WAVES experiments and (2) the Fourier, wavelet and higher order spectral analysis techniques. Using the in situ wave data, especially the high time resolution data observed during the local type II bursts, we will identify the nonlinear processes associated with these solar radio emissions. Comparing the estimated radio intensities by the known emission mechanisms for the observed peak Langmuir wave intensities with the observed peak radio intensities of type II bursts, we will identify the emission mechanisms.
Geometry and Raman spectra of P.R. 255 and its furo-furanone analogue
NASA Astrophysics Data System (ADS)
Luňák, Stanislav, Jr.; Frumarová, Božena; Vyňuchal, Jan; Hrdina, Radim
2009-05-01
Fourier transform Raman spectra of two π-isoelectronic compounds 3,6-diphenyl-2,5-dihydro-pyrrolo-[3,4-c]pyrrole-1,4-dione (BPPB, C.I. Pigment Red 255) and 3,6-diphenyl-2,5-dihydro-furo-[3,4-c]furanone (BFFB) with the same 1,4-diphenyl-buta-1,3-diene (DPB) backbone were first time measured in polycrystalline phase. The ground state geometry and vibrational frequencies together with Raman intensities were computed by density functional theory (DFT: B3LYP/6-311G++(d,p)). All intensive observed Raman frequencies were identified as totally symmetric. The difference of carbon-carbon bond lengths of BPPB and BFFB compared to DPB, relating very well with the shifts of C dbnd C and C-C stretching modes frequencies, was explained by aromatization of central butadiene unit bounded in diketo-pyrrolo-pyrrole and furo-furanone heterocycles. A strong coupling of modes was observed for BFFB enhancing selectively the intensity of one peak 1593 cm -1 in C dbnd C stretching region and one peak 1372 cm -1 in C-C stretching region. C dbnd O stretching and N-H bending modes of BPPB are significantly affected by intermolecular hydrogen bonding.
Changes in the Long-Term Intensity Variations in Cygnus X-2 and LMC X-3
NASA Astrophysics Data System (ADS)
Paul, B.; Kitamoto, S.; Makino, F.
2000-01-01
We report the detection of changes in the long-term intensity variations in two X-ray binaries, Cyg X-2 and LMC X-3. In this work, we have used the long-term light curves obtained with the All-Sky Monitors (ASMs) of the Rossi X-Ray Timing Explorer (RXTE), Ginga, Ariel 5, and Vela 5B and the scanning modulation collimator of HEAO 1. It is found that in the light curves of both the sources, obtained with these instruments at various times over the last 30 years, more than one periodic or quasi-periodic component is always present. The multiple prominent peaks in the periodograms have frequencies unrelated to each other. In Cyg X-2, RXTE-ASM data show strong peaks at 40.4 and 68.8 days, and Ginga-ASM data show strong peaks at 53.7 and 61.3 days. Multiple peaks are also observed in LMC X-3. The various strong peaks in the periodograms of LMC X-3 appear at 104, 169, and 216 days (observed with RXTE-ASM) and 105, 214, and 328 days (observed with Ginga-ASM). The present results, when compared with the earlier observations of periodicities in these two systems, demonstrate the absence of any stable long period. The 78 day periodicity detected earlier in Cyg X-2 was probably due to the short time base in the RXTE data that were used, and the periodicity of 198 days in LMC X-3 was due to a relatively short duration of observation with HEAO 1.
Conchola, Eric C; Thiele, Ryan M; Palmer, Ty B; Smith, Doug B; Thompson, Brennan J
2015-05-01
The aim of this study was to examine the effects of a medium-intensity high-volume vs. explosive squat protocol on the postexercise time course responses of maximal and rapid strength of the knee extensors. Seventeen resistance-trained men (mean ± SD: age = 22.0 ± 2.6 years) performed maximal voluntary contractions (MVCs) of the knee extensors before and after performing a squat workout using either a low-intensity fast velocity (LIFV) (5 × 16 at 40% 1 repetition maximum) or a traditional high-intensity slow velocity (TISV) (5 × 8 at 80% 1RM) exercise protocol. For each MVC, peak torque (PT), peak rate of torque development (RTDpeak), absolute (RTDabs), and relative RTD (RTDnorm) at early (0-50 milliseconds) and late (100-200 milliseconds) phases of muscle contraction were examined at pre- (Pre) and post-exercise at 0, 7, 15, and 30 (Post0...30) minutes. There were no intensity × time interactions for any variables (p = 0.098-0.832). Peak torque was greater at Pre than Post0 and Post7 (p = 0.001-0.016) but was not greater than Post15 and Post30 (p = 0.010-0.189). RTDpeak and early absolute RTD (RTD50abs) were greater at Pre than all postexercise time phases (p = 0.001-0.050); however, later absolute RTD (RTD100-200abs) was only greater at Pre than Post0 and Post30 (p = 0.013-0.048). Early relative RTD (RTD50norm) was only higher at Pre compared with Post0 (p = 0.023), whereas no differences were observed for later relative RTD (RTD100-200norm) (p = 0.920-0.990). Low-intensity fast velocity and TISV squat protocols both yielded acute decreases in maximal and rapid strength capacities following free-weight squats, with rapid strength showing slower recovery characteristics than maximal strength.
Saberi, Sara; Wheeler, Matthew; Bragg-Gresham, Jennifer; Hornsby, Whitney; Agarwal, Prachi P; Attili, Anil; Concannon, Maryann; Dries, Annika M; Shmargad, Yael; Salisbury, Heidi; Kumar, Suwen; Herrera, Jonathan J; Myers, Jonathan; Helms, Adam S; Ashley, Euan A; Day, Sharlene M
2017-04-04
Formulating exercise recommendations for patients with hypertrophic cardiomyopathy is challenging because of concern about triggering ventricular arrhythmias and because a clinical benefit has not been previously established in this population. To determine whether moderate-intensity exercise training improves exercise capacity in adults with hypertrophic cardiomyopathy. A randomized clinical trial involving 136 patients with hypertrophic cardiomyopathy was conducted between April 2010 and October 2015 at 2 academic medical centers in the United States (University of Michigan Health System and Stanford University Medical Center). Date of last follow-up was November 2016. Participants were randomly assigned to 16 weeks of moderate-intensity exercise training (n = 67) or usual activity (n = 69). The primary outcome measure was change in peak oxygen consumption from baseline to 16 weeks. Among the 136 randomized participants (mean age, 50.4 [SD, 13.3] years; 42% women), 113 (83%) completed the study. At 16 weeks, the change in mean peak oxygen consumption was +1.35 (95% CI, 0.50 to 2.21) mL/kg/min among participants in the exercise training group and +0.08 (95% CI, -0.62 to 0.79) mL/kg/min among participants in the usual-activity group (between-group difference, 1.27 [95% CI, 0.17 to 2.37]; P = .02). There were no occurrences of sustained ventricular arrhythmia, sudden cardiac arrest, appropriate defibrillator shock, or death in either group. In this preliminary study involving patients with hypertrophic cardiomyopathy, moderate-intensity exercise compared with usual activity resulted in a statistically significant but small increase in exercise capacity at 16 weeks. Further research is needed to understand the clinical importance of this finding in patients with hypertrophic cardiomyopathy, as well as the long-term safety of exercise at moderate and higher levels of intensity. clinicaltrials.gov Identifier: NCT01127061.
Signal intensity influences on the atomic Faraday filter.
Luo, Bin; Yin, Longfei; Xiong, Junyu; Chen, Jingbiao; Guo, Hong
2018-06-01
Previous studies of the Faraday anomalous dispersion optical filter (FADOF) mainly focus on the weak signal light filtering, without regard for the influences of the signal light intensity on the filter itself. However, in some applications the signal light is strong enough to change the filter's performance. In this work, the influences of the signal light intensity on the transmittance spectrum is experimentally investigated in a 780 nm Rb85 FADOF in both the line-center and wings operation modes. The results show that the transmittance spectrum varies significantly with the signal light intensity. As the signal light increases, some existing transmittance peaks decline, some new transmittance peaks appear, and the maximum transmittance peak frequency may change. The spectrum in strong signal lights can be quite different from those calculated by programs in the condition of weak signal lights. These results are important for applications of the FADOF in the condition of strong signal lights.
Abeysekara, Saman; Damiran, Daalkhaijav; Yu, Peiqiang
2013-02-01
The objectives of this study were (i) to determine lipid related molecular structures components (functional groups) in feed combination of cereal grain (barley, Hordeum vulgare) and wheat (Triticum aestivum) based dried distillers grain solubles (wheat DDGSs) from bioethanol processing at five different combination ratios using univariate and multivariate molecular spectral analyses with infrared Fourier transform molecular spectroscopy, and (ii) to correlate lipid-related molecular-functional structure spectral profile to nutrient profiles. The spectral intensity of (i) CH(3) asymmetric, CH(2) asymmetric, CH(3) symmetric and CH(2) symmetric groups, (ii) unsaturation (CC) group, and (iii) carbonyl ester (CO) group were determined. Spectral differences of functional groups were detected by hierarchical cluster analysis (HCA) and principal components analysis (PCA). The results showed that the combination treatments significantly inflicted modifications (P<0.05) in nutrient profile and lipid related molecular spectral intensity (CH(2) asymmetric stretching peak height, CH(2) symmetric stretching peak height, ratio of CH(2) to CH(3) symmetric stretching peak intensity, and carbonyl peak area). Ratio of CH(2) to CH(3) symmetric stretching peak intensity, and carbonyl peak significantly correlated with nutrient profiles. Both PCA and HCA differentiated lipid-related spectrum. In conclusion, the changes of lipid molecular structure spectral profiles through feed combination could be detected using molecular spectroscopy. These changes were associated with nutrient profiles and functionality. Copyright © 2012 Elsevier B.V. All rights reserved.
Justice, Tara D; Hammer, Greta L; Davey, Raymond J; Paramalingam, Nirubasini; Guelfi, Kym J; Lewis, Lynley; Davis, Elizabeth A; Jones, Timothy W; Fournier, Paul A
2015-05-01
This study investigated whether a prior bout of moderate-intensity exercise attenuates the glycemia-increasing effect of a maximal 30-sec sprint. A secondary aim was to determine whether the effect of antecedent exercise on the glucoregulatory response to sprinting is affected by sex. Participants (men n = 8; women n = 7) were tested on two occasions during which they either rested (CON) or cycled for 60-min at a moderate intensity of ~65% V ˙ O 2 peak (EX) before performing a 30-sec maximal cycling effort 195 min later. In response to the sprint, blood glucose increased to a similar extent between EX and CON trials, peaking at 10 min of recovery, with no difference between sexes (P > 0.05). Blood glucose then declined at a faster rate in EX, and this was associated with a glucose rate of disappearance (R d) that exceeded the glucose rate of appearance (R a) earlier in EX compared with CON, although the overall glucose R a and R d profile was higher in men compared with women (P < 0.05). The response of growth hormone was attenuated during recovery from EX compared with CON (P < 0.05), with a lower absolute response in women compared with men (P < 0.05). The response of epinephrine and norepinephrine was also lower in women compared with men (P < 0.05) but similar between trials. In summary, a prior bout of moderate-intensity exercise does not affect the magnitude of the glycemia-increasing response to a 30-sec sprint; however, the subsequent decline in blood glucose is more rapid. This blood glucose response is similar between men and women, despite less pronounced changes in glucose R a and R d, and a lower response of plasma catecholamines and growth hormone to sprinting in women. © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.
Impulsive excitation of mechanoluminescence in gamma-irradiated CaSO4:Eu phosphors
NASA Astrophysics Data System (ADS)
Kher, R. S.; Dhoble, S. J.; Pandey, R. K.; Upadhyay, A. K.; Khokhar, M. S. K.
2011-01-01
The mechanoluminescence (ML) and thermoluminescence (TL) of γ-irradiated CaSO4:Eu phosphor have been studied. CaSO4 samples having different concentrations of Eu were prepared by dissolving CaSO4.2H2O in sulphuric acid and evaporating the excess acid around 300 °C. ML was excited impulsively by dropping a load onto the sample. Three distinct peaks have been observed in the ML intensity versus time curve. The ML intensity increases with the increasing concentration of the dopant. The effect of temperature on the shape and peak of ML intensity was also recorded. Growth, saturation and broadening in an ML peak were observed. TL glow curves of CaSO4:Eu phosphors at different concentrations contain two TL peaks: the first peak was observed at around 110 °C and the other at 210 °C. Experimental results suggest that the ML excitation is related to the movement of dislocation with defect centres, the increase in ML with temperature is due to the enhancement in dislocation capture probability, and the reduction is due to the thermal bleaching of defect centres.
Peak picking NMR spectral data using non-negative matrix factorization
2014-01-01
Background Simple peak-picking algorithms, such as those based on lineshape fitting, perform well when peaks are completely resolved in multidimensional NMR spectra, but often produce wrong intensities and frequencies for overlapping peak clusters. For example, NOESY-type spectra have considerable overlaps leading to significant peak-picking intensity errors, which can result in erroneous structural restraints. Precise frequencies are critical for unambiguous resonance assignments. Results To alleviate this problem, a more sophisticated peaks decomposition algorithm, based on non-negative matrix factorization (NMF), was developed. We produce peak shapes from Fourier-transformed NMR spectra. Apart from its main goal of deriving components from spectra and producing peak lists automatically, the NMF approach can also be applied if the positions of some peaks are known a priori, e.g. from consistently referenced spectral dimensions of other experiments. Conclusions Application of the NMF algorithm to a three-dimensional peak list of the 23 kDa bi-domain section of the RcsD protein (RcsD-ABL-HPt, residues 688-890) as well as to synthetic HSQC data shows that peaks can be picked accurately also in spectral regions with strong overlap. PMID:24511909
Effects of different set configurations on barbell velocity and displacement during a clean pull.
Haff, G Gregory; Whitley, Adrian; McCoy, Lora B; O'Bryant, Harold S; Kilgore, J Lon; Haff, Erin E; Pierce, Kyle; Stone, Michael H
2003-02-01
The effects of 3 types of set configurations (cluster, traditional, and undulating) on barbell kinematics were investigated in the present study. Thirteen men (track and field = 8; Olympic weightlifters = 5) (mean +/- SEM age, 23.4 +/- 1.1 years; height, 181.3 +/- 2.1 cm; body mass, 89.8 +/- 4.2 kg) performed 1 set of 5 repetitions in a cluster, traditional, and undulating fashion at 90 and 120% of their 1 repetition maximum (1RM) power clean (119.0 +/- 4.3 kg). All data were collected at 50 Hz and analyzed with a V-Scope Weightlifting Analysis System. Peak velocity (PV) and peak displacement (PD) were analyzed for each repetition and averaged for each set type. Results indicated that a significantly (p < 0.016) higher PV occurred during the cluster set when compared with the traditional sets at both intensities. PD was significantly higher than traditional sets at the 120% intensity. The present study suggests set configuration can affect PV and PD during clean pulls.
Echo 2 - Observations at Fort Churchill of a 4-keV peak in low-level electron precipitation
NASA Technical Reports Server (NTRS)
Arnoldy, R. L.; Hendrickson, R. A.; Winckler, J. R.
1975-01-01
The Echo 2 rocket flight launched from Fort Churchill, Manitoba, offered the opportunity to observe high-latitude low-level electron precipitation during quiet magnetic conditions. Although no visual aurora was evident at the time of the flight, an auroral spectrum sharply peaked at a few keV was observed to have intensities from 1 to 2 orders of magnitude lower than peaked spectra typically associated with bright auroral forms. There is a growing body of evidence that relates peaked electron spectra to discrete aurora. The Echo 2 observations show that whatever the mechanism for peaking the electron spectrum in and above discrete forms, it operates over a range of precipitation intensities covering nearly 3 orders of magnitude down to subvisual or near subvisual events.
Noble metal nanostructures for double plasmon resonance with tunable properties
NASA Astrophysics Data System (ADS)
Petr, M.; Kylián, O.; Kuzminova, A.; Kratochvíl, J.; Khalakhan, I.; Hanuš, J.; Biederman, H.
2017-02-01
We report and compare two vacuum-based strategies to produce Ag/Au materials characterized by double plasmon resonance peaks: magnetron sputtering and method based on the use of gas aggregation sources (GAS) of nanoparticles. It was observed that the double plasmon resonance peaks may be achieved by both of these methods and that the intensities of individual localized surface plasmon resonance peaks may be tuned by deposition conditions. However, in the case of sputter deposition it was necessary to introduce a separation dielectric interlayer in between individual Ag and Au nanoparticle films which was not the case of films prepared by GAS systems. The differences in the optical properties of sputter deposited bimetallic Ag/Au films and coatings consisted of individual Ag and Au nanoparticles produced by GAS is ascribed to the divers mechanisms of nanoparticles formation.
Wormgoor, Shohn G; Dalleck, Lance C; Zinn, Caryn; Harris, Nigel K
2018-01-01
Optimizing exercise-induced physiological responses without increasing the risk of negative exaggerated responses is an important aspect of exercise prescription for people with type 2 diabetes mellitus (T2DM). However, knowledge of acute responses, including exaggerated responses, of different training modalities is limited. The aim of the study was to compare acute physiological responses of moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT) in T2DM. Baseline data were used to randomly assign male participants into supervised training groups for a 12-week intervention. During week 7, participants trialed either a fully progressed MICT (N.=11) or HIIT (N.=11) (combined with resistance training) session. The MICT included 26 minutes at 55% estimated maximum workload (eWLmax) while the HIIT included twelve 1-minute bouts at 95% eWLmax interspersed with 1-minute bouts at 40% eWLmax. While energy expenditure and peak systolic and diastolic blood pressure responses were similar between groups (P=0.47, P=0.71, P=0.56, respectively), peak heart rate, workload and perceived exertion were higher in the HIIT group (P=0.04, P<0.001, and P<0.001, respectively). Acute exaggerated responses were similar (P=0.39) for MICT (64%) and HIIT (36%) participants. While structured MICT and HIIT sessions resulted in comparable acute physiological responses, the individual variations and exaggerated responses, even after preparatory training, necessitated precautionary respite in T2DM men.
Tsaklis, Panagiotis; Malliaropoulos, Nikos; Mendiguchia, Jurdan; Korakakis, Vasileios; Tsapralis, Kyriakos; Pyne, Debasish; Malliaras, Peter
2015-01-01
Background Hamstring injuries are common in many sports, including track and field. Strains occur in different parts of the hamstring muscle but very little is known about whether common hamstring loading exercises specifically load different hamstring components. The purpose of this study was to investigate muscle activation of different components of the hamstring muscle during common hamstring loading exercises. Methods Twenty elite female track and field athletes were recruited into this study, which had a single-sample, repeated-measures design. Each athlete performed ten hamstring loading exercises, and an electromyogram (EMG) was recorded from the biceps femoris and semitendinosus components of the hamstring. Hamstring EMG during maximal voluntary isometric contraction (MVIC) was used to normalize the mean data across ten repetitions of each exercise. An electrogoniometer synchronized to the EMG was used to determine whether peak EMG activity occurred during muscle-tendon unit lengthening, shortening, or no change in length. Mean EMG values were compared between the two recording sites for each exercise using the Student’s t-test. Results The lunge, dead lift, and kettle swings were low intensity (<50% MVIC) and all showed higher EMG activity for semitendinosus than for biceps femoris. Bridge was low but approaching medium intensity, and the TRX, hamstring bridge, and hamstring curl were all medium intensity exercises (≥50% or <80% MVIC). The Nordic, fitball, and slide leg exercises were all high intensity exercises. Only the fitball exercise showed higher EMG activity in the biceps femoris compared with the semitendinosus. Only lunge and kettle swings showed peak EMG in the muscle-tendon unit lengthening phase and both these exercises involved faster speed. Conclusion Some exercises selectively activated the lateral and medial distal hamstrings. Low, medium, and high intensity exercises were demonstrated. This information enables the clinician, strength and conditioning coach and physiotherapist to better understand intensity- and muscle-specific activation during hamstring muscle rehabilitation. Therefore, these results may help in designing progressive strengthening and rehabilitation and prevention programs. PMID:26170726
Barua, Animesh; Bitterman, Pincas; Bahr, Janice M.; Basu, Sanjib; Sheiner, Eyal; Bradaric, Michael J.; Hales, Dale B.; Luborsky, Judith L.; Abramowicz, Jacques S.
2011-01-01
Objective Our goal was to examine the feasibility of using laying hens, a preclinical model of human spontaneous ovarian cancer, in determining the kinetics of an ultrasound contrast agent indicative of ovarian tumor-associated neoangiogenesis in early-stage ovarian cancer. Methods Three-year-old White Leghorn laying hens with decreased ovarian function were scanned before and after intravenous injection of a human serum albumin–perflutren contrast agent at a dose of 5 µL/kg body weight. Gray scale morphologic characteristics, Doppler indices, the arrival time, peak intensity, and wash-out of the contrast agent were recorded and archived on still images and video clips. Hens were euthanized thereafter; sonographic predictions were compared at gross examination; and ovarian tissues were collected. Archived clips were analyzed to determine contrast parameters and Doppler intensities of vessels. A time-intensity curve per hen was drawn, and the area under the curve was derived. Tumor types and the density of ovarian microvessels were determined by histologic examination and immunohistochemistry and compared to sonographic predictions. Results The contrast agent significantly (P < .05) enhanced the visualization of microvessels, which was confirmed by immunohistochemistry. Contrast parameters, including the time of wash-out and area under the curve, were significantly different (P < .05) between ovaries of normal hens and hens with ovarian cancer and correctly detected cancer at earlier stages than the time of peak intensity. Conclusions The laying hen may be a useful animal model for determining ovarian tumor-associated vascular kinetics diagnostic of early-stage ovarian cancer using a contrast agent. This model may also be useful for testing the efficacy of different contrast agents in a preclinical setting. PMID:21357555
Diffuse Scattering Investigations of Orientational Pair Potentials in C_60
NASA Astrophysics Data System (ADS)
Wochner, Peter
1996-03-01
Premonitory orientational fluctuations above the first order phase transition of C_60 at 260K have been studied by diffuse X-ray scattering experiments. These experiments probe the orientational pair correlations between C_60 molecules as a function of their separation and therefore the orientational pair potential. In addition to the diffuse scattering due to the orientational disorder of single molecules, we have observed zone boundary diffuse scattering at the X-points related to the Pabar 3 low temperature structure up to 300K. An additional set of diffuse peaks, which are even at room temperature comparable in intensity to the former ones, have been found at (0.5,0.5,0.5) positions (L-point). Similar results have recently been reported by P. Launois et al. (P. Launois, S. Ravy, R. Moret, PRB 52), 5414 (1995) and L. Pintschovius et al. (L. Pintschovius, S.L. Chaplot, G. Roth, G. Heger, PRL 75), 2843 (1995) The temperature dependence of the integrated intensity of both sets of diffuse peaks shows only a weak increase in approaching T_c, indicative of a strongly first order transition. Additional intensity with a very weak temperature dependence but similar correlation length has also been found at (0.5,0.5,0) and (0.5,0,0) positions. The diffuse intensity at the L, Σ and Δ points has probably its origin in competing phases which are not stabilized at low temperatures. Recent DSC measurements show close lying transitions at 260K with a separation of ~= 0.2-0.3K which might be related to these competing phases footnote J. Fischer, private communication. The data will be compared with model calculations using orientational pair potentials which have been used in literature to describe the orientational phase transition in C_60.
Peak Velocity as an Alternative Method for Training Prescription in Mice.
Picoli, Caroline de Carvalho; Romero, Paulo Vitor da Silva; Gilio, Gustavo R; Guariglia, Débora A; Tófolo, Laize P; de Moraes, Solange M F; Machado, Fabiana A; Peres, Sidney B
2018-01-01
Purpose: To compare the efficiency of an aerobic physical training program prescribed according to either velocity associated with maximum oxygen uptake (vVO 2max ) or peak running speed obtained during an incremental treadmill test (V peak_K ) in mice. Methods: Twenty male Swiss mice, 60 days old, were randomly divided into two groups with 10 animals each: 1. group trained by vVO 2max (GVO 2 ), 2. group trained by V peak_K (GVP). After the adaptation training period, an incremental test was performed at the beginning of each week to adjust training load and to determine the amount of VO 2 and VCO 2 fluxes consumed, energy expenditure (EE) and run distance during the incremental test. Mice were submitted to 4 weeks of aerobic exercise training of moderate intensity (velocity referring to 70% of vVO 2max and V peak_K ) in a programmable treadmill. The sessions lasted from 30 to 40 min in the first week, to reach 60 min in the fourth week, in order to provide the mice with a moderate intensity exercise, totaling 20 training sessions. Results: Mice demonstrated increases in VO 2max (ml·kg -1 ·min -1 ) (GVO 2 = 49.1% and GVP = 56.2%), V peak_K (cm·s -1 ) (GVO 2 = 50.9% and GVP = 22.3%), EE (ml·kg -0,75 ·min -1 ) (GVO 2 = 39.9% and GVP = 51.5%), and run distance (cm) (GVO 2 = 43.5% and GVP = 33.4%), after 4 weeks of aerobic training (time effect, P < 0.05); there were no differences between the groups. Conclusions: V peak_K , as well as vVO 2max , can be adopted as an alternative test to determine the performance and correct prescription of systemized aerobic protocol training to mice.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, W. L.; Qiao, B., E-mail: bqiao@pku.edu.cn; Huang, T. W.
2016-07-15
Ion acceleration in near-critical plasmas driven by intense laser pulses is investigated theoretically and numerically. A theoretical model has been given for clarification of the ion acceleration dynamics in relation to different laser and target parameters. Two distinct regimes have been identified, where ions are accelerated by, respectively, the laser-induced shock wave in the weakly driven regime (comparatively low laser intensity) and the nonlinear solitary wave in the strongly driven regime (comparatively high laser intensity). Two-dimensional particle-in-cell simulations show that quasi-monoenergetic proton beams with a peak energy of 94.6 MeV and an energy spread 15.8% are obtained by intense laser pulsesmore » at intensity I{sub 0} = 3 × 10{sup 20 }W/cm{sup 2} and pulse duration τ = 0.5 ps in the strongly driven regime, which is more advantageous than that got in the weakly driven regime. In addition, 233 MeV proton beams with narrow spread can be produced by extending τ to 1.0 ps in the strongly driven regime.« less
Allen, Trevor I.; Wald, David J.
2009-01-01
Regional differences in ground-motion attenuation have long been thought to add uncertainty in the prediction of ground motion. However, a growing body of evidence suggests that regional differences in ground-motion attenuation may not be as significant as previously thought and that the key differences between regions may be a consequence of limitations in ground-motion datasets over incomplete magnitude and distance ranges. Undoubtedly, regional differences in attenuation can exist owing to differences in crustal structure and tectonic setting, and these can contribute to differences in ground-motion attenuation at larger source-receiver distances. Herein, we examine the use of a variety of techniques for the prediction of several ground-motion metrics (peak ground acceleration and velocity, response spectral ordinates, and macroseismic intensity) and compare them against a global dataset of instrumental ground-motion recordings and intensity assignments. The primary goal of this study is to determine whether existing ground-motion prediction techniques are applicable for use in the U.S. Geological Survey's Global ShakeMap and Prompt Assessment of Global Earthquakes for Response (PAGER). We seek the most appropriate ground-motion predictive technique, or techniques, for each of the tectonic regimes considered: shallow active crust, subduction zone, and stable continental region.
NASA Astrophysics Data System (ADS)
Zheng, T.
2015-12-01
A goal of carbon (C) emission peaking around 2030 of China was declared in the China-U.S. joint statement on climate change, and emphasized in China's intended nationally determined contributions (INDC). Here, we predicted the carbon emission of China during the period 2011~2050 under seven scenarios, and analyzed the scientific and social implications of realizing the goal. Our results showed that: (1) C emissions of China will reach their peaks at 2022~2045 (with peak values 3.15~5.10 Pg C), and the predicted decay rates of C intensity were 2.1~4.2% in 2011~2050; (2) the precondition that the national C emission reaches the peak before 2030 is that the annual decay rates of C intensity must exceed 3.3% , as decay rates under different scenarios were predicted higher than that except for Past G8 scenario; (3) the national C emission would reach the peak before 2030, if the government of China should realize the C emissions reduction goals of China's 12th five-year plan, climate commitments of Copenhagen and INDC; (4) Chinese government could realize the goal of C emission peaking around 2030 from just controlling C emission intensity , but associated with relatively higher government's burden. In summary, China's C emission may well peak before 2030, meanwhile the combination of emissions reduction and economic macro-control would be demanded to avoid heavier social pressure of C emissions reduction occurred.
Gillick, Bernadette T.; Kirton, Adam; Carmel, Jason B.; Minhas, Preet; Bikson, Marom
2014-01-01
Background: Transcranial direct current stimulation (tDCS) has been investigated mainly in adults and doses may not be appropriate in pediatric applications. In perinatal stroke where potential applications are promising, rational adaptation of dosage for children remains under investigation. Objective: Construct child-specific tDCS dosing parameters through case study within a perinatal stroke tDCS safety and feasibility trial. Methods: 10-year-old subject with a diagnosis of presumed perinatal ischemic stroke and hemiparesis was identified. T1 magnetic resonance imaging (MRI) scans used to derive computerized model for current flow and electrode positions. Workflow using modeling results and consideration of dosage in previous clinical trials was incorporated. Prior ad hoc adult montages vs. de novo optimized montages provided distinct risk benefit analysis. Approximating adult dose required consideration of changes in both peak brain current flow and distribution which further tradeoff between maximizing efficacy and adding safety factors. Electrode size, position, current intensity, compliance voltage, and duration were controlled independently in this process. Results: Brain electric fields modeled and compared to values previously predicted models (Datta et al., 2011; Minhas et al., 2012). Approximating conservative brain current flow patterns and intensities used in previous adult trials for comparable indications, the optimal current intensity established was 0.7 mA for 10 min with a tDCS C3/C4 montage. Specifically 0.7 mA produced comparable peak brain current intensity of an average adult receiving 1.0 mA. Electrode size of 5 × 7 cm2 with 1.0 mA and low-voltage tDCS was employed to maximize tolerability. Safety and feasibility confirmed with subject tolerating the session well and no serious adverse events. Conclusion: Rational approaches to dose customization, with steps informed by computational modeling, may improve guidance for pediatric stroke tDCS trials. PMID:25285077
Magnetic field induced enhancement of resistance in polycrystalline ZrTe5
NASA Astrophysics Data System (ADS)
Behera, Prakash; Bera, Sumit; Patidar, Manju Mishra; Singh, Durgesh; Mishra, A. K.; Krishnan, M.; Gangrade, M.; Deshpande, U. P.; Venkatesh, R.; Ganesan, V.
2018-04-01
Transport properties of the polycrystalline ZrTe5 showing a considerable positive Magneto-Resistance (MR) in the intermediate temperatures has been reported. Substantial shift of peak temperature by approximately 65 K with an applied magnetic field of 13.5 Tesla has been observed. Magneto resistance of this polycrystalline sample (˜100%) is comparable with its single crystalline counterpart reported in literature. The peak intensity scales with peak temperature and obeys reasonably the Dionne relationship that is a clear indication of polaron mediated conduction in this system. Magneto Resistance (MR) in this system is attributed to the two carrier polaronic conduction model similar to the Holstein's approach. The results are further complemented with the Peak shift in magnetic field expected for a system having a fraction of localized carrier density. This observation places this famous thermoelectric material that displays a topological Dirac to Weyl transition in magnetic field in to the family of materials that have potential technological applications in the liquid nitrogen temperature range viz. 85-150 K.
Observation of strain effect on the suspended graphene by polarized Raman spectroscopy
2012-01-01
We report the strain effect of suspended graphene prepared by micromechanical method. Under a fixed measurement orientation of scattered light, the position of the 2D peaks changes with incident polarization directions. This phenomenon is explained by a proposed mode in which the peak is effectively contributed by an unstrained and two uniaxial-strained sub-areas. The two axes are tensile strain. Compared to the unstrained sub-mode frequency of 2,672 cm−1, the tension causes a red shift. The 2D peak variation originates in that the three effective sub-modes correlate with the light polarization through different relations. We develop a method to quantitatively analyze the positions, intensities, and polarization dependences of the three sub-peaks. The analysis reflects the local strain, which changes with detected area of the graphene film. The measurement can be extended to detect the strain distribution of the film and, thus, is a promising technology on graphene characterization. PMID:23013616
Smith-Ryan, Abbie E.; Trexler, Eric T.; Wingfield, Hailee; Blue, Malia N.M.
2016-01-01
The purpose of this study was to evaluate two practical interval training protocols on cardiorespiratory fitness, lipids, and body composition in overweight/obese women. Thirty women (mean ± SD; Weight: 88.1 ± 15.9 kg; BMI: 32.0 ± 6.0 kg·m2) were randomly assigned to ten 1-minute high-intensity intervals (90%VO2peak, 1min recovery), or five 2-minute high-intensity intervals (80-100% VO2peak, 1 min recovery), or control. Peak oxygen uptake (VO2peak), peak power output, body composition, and fasting blood lipids were evaluated before and after 3 weeks of training, completed 3 days per week. Results from ANCOVA analyses demonstrated no significant training group differences for any primary variables (p>0.05). When training groups were collapsed, 1MIN and 2MIN resulted in a significant increase in peak power output (∆18.9 ± 8.5 watts; p=0.014) and time to exhaustion (∆55.1 ± 16.4 sec; p=0.001); non-significant increase in VO2peak (∆2.36 ± 1.34 ml·kg−1·min−1; p=0.185); and a significant decrease in fat mass (∆−1.96 ± 0.99kg; p=0.011). Short-term interval exercise training may be effective for decreasing fat mass and improving exercise tolerance in overweight and obese women. PMID:26934687
Osuka, Yosuke; Matsubara, Muneaki; Hamasaki, Ai; Hiramatsu, Yuji; Ohshima, Hiroshi; Tanaka, Kiyoji
2017-01-01
The purposes of this study were to identify 1) the feasibility of a novel exercise protocol (elderly Japanese male version of high-intensity interval aerobic training: EJ-HIAT) and 2) its preliminary data (%V̇O 2peak , rating of perceived exertion) in comparison with traditional moderate-intensity continuous aerobic training (MICT). Twenty-one sedentary elderly men, aged 60-69 years, performed two exercise protocols: EJ-HIAT, consisting of 3 sets of 2-3-min cycling at 75-85%V̇O 2peak with 1-2-min active rests at 50%V̇O 2peak between sets, and MICT, consisting of 40-min cycling at 65%V̇O 2peak . The completion rate, defined as the rate of participants who 1) did not demand withdrawal, 2) were not interrupted by the tester, and 3) did not change the workload during either exercise protocol, of EJ-HIAT was similar to that of MICT (EJ-HIAT: 100%, MICT: 95.2%). Maximal perceived exertion ratings assessed by Borg scale were also similar between EJ-HIAT and MICT. However, objectively measured maximal intensity assessed by %V̇O 2peak was higher for EJ-HIAT than for MICT (EJ-HIAT: 86.0 ± 5.6%, MICT: 67.1 ± 6.4%). These results suggested that EJ-HIAT has good feasibility and perceived exertion similar to MICT despite having higher objectively measured intensity than MICT. An intervention aimed as identifying the effects of EJ-HIAT on exercise tolerance should be performed in the future. UMIN000021185 (February 26, 2016).
NASA Astrophysics Data System (ADS)
Flament, C.; Gallet, F.; Graner, F.; Goldmann, M.; Peterson, I.; Renault, A.
1994-06-01
Grazing incidence X-ray diffraction is performed on a Langmuir monolayer made of pure fluorescent NBD-stearic acid, spread at the free surface of water. It shows several intense narrow peaks in the solid phase, at the same wavevectors as the brightest peaks observed earlier by electron diffraction, for a monolayer transferred onto an amorphous polymer substrate. Thus the solid phase has the same crystalline structure on water and on solid substrate. The relative peak intensities are comparable in both experiments, and in the proposed model for the molecular structure. This model also accounts for the very large anisotropy of the crystalline phase and its optical properties. This phase could be ferroelectric, as previously assumed in order to explain the elongated shape of the crystals. Une monocouche de Langmuir, composée d'acide NBD-stéarique fluorescent pur, déposée à la surface libre de l'eau, est analysée par diffraction de rayons X sous incidence rasante. On détecte plusieurs pics étroits et intenses dans la phase solide, aux mêmes vecteurs d'onde que les pics les plus brillants précédemment observés par diffraction électronique, pour une monocouche transférée sur un substrat de polymère amorphe. La phase solide a donc la même structure cristalline sur l'eau et sur substrat solide. Les intensités relatives des pics sont comparables dans les deux expériences, ainsi que dans le modèle proposé pour la structure moléculaire. Ce modèle rend également compte de l'anisotropie très importante de la phase cristalline et de ses propriétés optiques. Il pourrait s'agir d'une phase ferroélectrique, comme cela avait été précédemment supposé pour expliquer la forme allongée des cristaux.
Vertically Oriented Graphene Electrochemical Double Layer Capacitor with Very Fast Dynamic Response
2013-01-01
cauliflower type of morphology (see Figure A-2c). Figure A-3. (a) The intensity of D to G peak ratio in Raman spectra and the thickness (height) of...in a random, cauliflower type of morphology (see Figure A-2c). Figure A-2. (a) The intensity of D to G peak ratio in Raman spectra and the
NASA Astrophysics Data System (ADS)
Oks, E.
2016-05-01
It should have been noted that the theoretical spectra in Figs. 5 and 6, as well the numerical results for theoretical ratio of intensities of the central and lateral peaks (presented in the paragraph after Fig. 5), were calculated for the observation at the angle of 55° with respect to the magnetic field in tokamak T-10 (at this angle, the central and lateral peaks would have equal intensities while disregarding the effect of the spiraling trajectories of the electrons). At smaller angles of the observation, the effect of the spiraling trajectories of the electrons would be even more significant than presented in Figs. 5 and 6, and in the numerical data after Fig. 5. For example, for the observation at the angle of 45°, the allowance for the spiraling trajectories of the perturbing electrons increases the ratio of the intensity of the central peak to the intensity of any of the two lateral peaks by 100% (while at the angle of 55° the corresponding increase was 58%).
Relationship between SEP Peak intensity and CME Acceleration, Speed and Width
NASA Astrophysics Data System (ADS)
Xie, H.; St Cyr, O. C.; Makela, P. A.; Gopalswamy, N.
2017-12-01
We study the large solar energetic particle (SEP) events that were detected by GOES in the >10 MeV energy channel during December 2006 to January 2016. Data used in this study includes the Solar Electron Proton Telescope (SEPT) and High Energy Telescopes (HET) on STEREO A and B, the Electron, Proton, and Alpha Monitor (EPAM) on ACE, and the Energetic and Relativistic Nuclei and Electron instrument (ERNE) on SOHO. By choosing the smallest connection angles between SEP solar locations and magnetic foot-points of each spacecraft, we divide SEP events as SOHO SEPs or STEREO SEPs. We then compute the SEP peak intensity I0 at the center of the Gausssian using the Gausssian expression from Richardson et al. (2014) and study the relationship between SEP electron and proton peak intensity and CME acceleration, speed and width. By using I0 derived from multi-spacecraft observations we found that the correlations between SEP peak intensity and CME acceleration and speed improved. We also found that this correlation can be further improved by taking into account the effects of CME width and its solar source latitude. The implication for the SEP forecast of our obtained results will be discussed.
Impact of NICU design on environmental noise.
Szymczak, Stacy E; Shellhaas, Renée A
2014-04-01
For neonates requiring intensive care, the optimal sound environment is uncertain. Minimal disruptions from medical staff create quieter environments for sleep, but limit language exposure necessary for proper language development. There are two models of neonatal intensive care units (NICUs): open-bay, in which 6-to-10 infants are cared for in a single large room; and single-room, in which neonates are housed in private, individual hospital rooms. We compared the acoustic environments in the two NICU models. We extracted the audio tracks from video-electroencephalography (EEG) monitoring studies from neonates in an open-bay NICU and compared the acoustic environment to that recorded from neonates in a new single-room NICU. From each NICU, 18 term infants were studied (total N=36; mean gestational age 39.3±1.9 weeks). Neither z-scores of the sound level variance (0.088±0.03 vs. 0.083±0.03, p=0.7), nor percent time with peak sound variance (above 2 standard deviations; 3.6% vs. 3.8%, p=0.6) were different. However, time below 0.05 standard deviations was higher in the single-room NICU (76% vs. 70%, p=0.02). We provide objective evidence that single-room NICUs have equal sound peaks and overall noise level variability compared with open-bay units, but the former may offer significantly more time at lower noise levels.
Rampon, Vincent; Brossard, Chantal; Mouhous-Riou, Nadine; Bousseau, Benoît; Llamas, Geneviève; Genot, Claude
2004-05-20
Proteins are widely used as emulsifiers in food emulsions. Model emulsions, designed to study emulsifying properties of proteins and their conformation at the interfaces often contain a hydrocarbon as apolar phase instead of natural triglycerides as found in food products. Yet, some results indicate that the protein conformation at the interface depends on the nature of the apolar phase. Front-surface fluorescence spectroscopy was used to evidence differences in the structure of bovine serum albumin (BSA) adsorbed at the interface of emulsions prepared with different apolar phases: an hydrocarbon (n-dodecane), a synthetic medium-chain triglyceride (miglyol) and a natural vegetable oil (sunflower oil). Emulsions had similar size distributions of oil droplets. Front-surface fluorescence emission spectra of tryptophanyl residues of the protein (Trp) in emulsions, creams and serums varied as a function of the nature of hydrophobic phase. In emulsions and creams, wavelength of the maximum fluorescence intensities was blue-shifted as compared to the BSA solution. The shift was larger in creams than in emulsions and in samples containing dodecane than with the other apolar phases. Fourth derivative spectra of emulsions and creams exhibited two peaks assigned, respectively, to Trp located in hydrophilic and hydrophobic environments. The peaks were slightly red-shifted in the presence of sunflower oil as compared to miglyol and dodecane and the relative intensity of the "hydrophobic peak" was higher in dodecane. The effects were greater in creams than in emulsions. Fluorescence intensity of Trp was the highest in the serums of emulsions prepared with dodecane as compared to serums issued from sunflower oil and miglyol emulsions. Thus, proportion of adsorbed protein was lower in dodecane emulsions than with the other apolar phases. These results evidence that the mean environment of Trp was more hydrophobic in emulsions and creams than in solutions due to a displacement of some of the Trp of the protein to a more hydrophobic environment. Dodecane had the greatest impact on Trp environment (more hydrophobic) followed by miglyol and then by sunflower oil. This is likely due to differences in the conformation of the protein at the hydrocarbon-water interface as compared to the triacylglycerol-water ones. In addition, sunflower oil provoked a large decrease of Trp fluorescence intensity in emulsions and creams as compared to miglyol or dodecane. This could be due to contaminant quenchers in the oil or to interactions of the unsaturated fatty chains with the protein inducing quenching of the Trp. These observations should be related to the physical properties of the apolar phase and its molecular organization and interactions with the protein at the interface.
High-Intensity Interval or Continuous-Moderate Exercise: A 24-Week Pilot Trial.
Locke, Sean R; Bourne, Jessica E; Beauchamp, Mark R; Little, Jonathan P; Barry, Julianne; Singer, Joel; Jung, Mary E
2018-05-14
High-intensity interval training (HIIT) may lead to superior cardiometabolic improvements when compared to moderate-intensity continuous training (MICT). However, adherence to HIIT requires examination. The purpose of this pilot study was to examine moderate-to-vigorous physical activity (MVPA) adherence 24 weeks following a brief counselling intervention combined with either HIIT or MICT. Individuals at high risk of type 2 diabetes (T2D) were randomized to HIIT (n = 15) or MICT (n = 17) and completed 10 exercise sessions accompanied by a brief 10-minute counselling intervention over a 2-week period. Objectively measured purposeful MVPA (accelerometry) and cardiorespiratory fitness (VO2peak) were assessed at baseline and 24 weeks post-intervention. Self-regulatory efficacy and task self-efficacy were examined at baseline, post-intervention and 24 weeks post-intervention. Using an intention-to-treat analysis, change scores were calculated for HIIT and MICT and compared between groups. Individuals assigned to HIIT increased their MVPA by 53 minutes (Cohen's d=1.52) at 24 weeks compared to 19 minutes in MICT (tbetween=1.96, p=.06, d =.56). Both HIIT and MICT increased relative VO2peak by 2 and 1 ml/kg/min, respectively (tbetween=0.72, p=0.47). Participants in both groups increased in their self-regulatory and task self-efficacy post-intervention but both groups demonstrated similar decline at 24 weeks. This pilot intervention was successful in increasing, and maintaining, free-living MVPA over a 24-week period in individuals at high risk of T2D. Speculation that HIIT is inappropriate or unattainable for overweight individuals at high risk of T2D may be unfounded.
Experimental band structure of potassium as measured by angle-resolved photoemission
DOE Office of Scientific and Technical Information (OSTI.GOV)
Itchkawitz, B.S.; Lyo, I.; Plummer, E.W.
1990-04-15
The bulk band structure of potassium along the (110) direction was measured using angle-resolved photoemission from an epitaxial potassium film several thousand angstroms thick grown on a Ni(100) substrate. We find the occupied bandwidth to be 1.60{plus minus}0.05 eV, which is narrower than the free-electron bandwidth of 2.12 eV and agrees with recent calculations of the quasiparticle self-energy. A narrow peak near the Fermi level which did not disperse with photon energy was observed for photon energies which, according to the nearly-free-electron model, should yield no direct transitions. A comparison of the binding energy and intensity of the anomalous peakmore » as functions of photon energy is made to the calculations of Shung and Mahan (Phys. Rev. B 38, 3856 (1988)). The discrepancies found are discussed in terms of an enhanced surface photoeffect in the photon energy range 20{le}{h bar}{omega}{le}30 eV. For low photon energies, a bulk peak was also observed due to a surface umklapp process with an intensity comparable to the standard bulk (110) peak. The possible contributions to this strong surface umklapp process from a shear instability at the first few (110) atomic planes is discussed.« less
NASA Astrophysics Data System (ADS)
Sordillo, Laura A.; Sordillo, Peter P.; Budansky, Yury; Pu, Yang; Alfano, R. R.
2015-03-01
Fluorescence profiles from breast cancer and breast normal tissue samples with excitation wavelengths at 280 nm and 340 nm were obtained using the conventional LS-50 Perkin-Elmer spectrometer. Fluorescence ratios from these tissue samples, demonstrated by emission peaks at 340 nm, 440 nm and 460 nm and likely representing tryptophan and NADH, show increased relative content of tryptophan in malignant samples. Double ratio (DR) techniques were used to measure the severity of disease. The single excitation double ratio (Single-DR) method utilizes the emission intensity peaks from the spectrum acquired using a single excitation of 280 nm; while the dual excitation double ratio (dual-DR) method utilizes the emission intensity peaks from the spectra acquired using an excitation of 280 nm and 340 nm. Single-DR and dual-DR from 13 patients with breast carcinoma were compared in terms of their efficiency to distinguish high from low/intermediate tumors. Similar results were found with both methods. Results suggest that dual excitation wavelengths may be as effective as single excitation wavelength in calculating the relative content of biomolecules in breast cancer tissue, as well as for the assessment of the malignant potential of these tumors.
Effect of 8 Weeks Soccer Training on Health and Physical Performance in Untrained Women.
Ortiz, Jaelson G; da Silva, Juliano F; Carminatti, Lorival J; Guglielmo, Luiz G A; Diefenthaeler, Fernando
2018-03-01
This study aims to analyze the physiological, neuromuscular, and biochemical responses in untrained women after eight weeks of regular participation in small-sided soccer games compared to aerobic training. Twenty-seven healthy untrained women were divided into two groups [soccer group (SG = 17) and running group (RG = 10)]. Both groups trained three times per week for eight weeks. The variables measured in this study were maximal oxygen uptake (VO 2 max), relative velocity at VO 2 max (vVO 2 max), peak velocity, relative intensity at lactate threshold (vLT), relative intensity at onset of blood lactate accumulation (vOBLA), peak force, total cholesterol, HDL, LDL, triglycerides, and cholesterol ratio (LDL/HDL). VO 2 max, vLT, and vOBLA increased significantly in both groups (12.8 and 16.7%, 11.1 and 15.3%, 11.6 and 19.8%, in SG and RG respectively). However, knee extensors peak isometric strength and triglyceride levels, total cholesterol, LDL, and HDL did not differ after eight weeks of training in both groups. On the other hand, the LDL/HDL ratio significantly reduced in both groups. In conclusion, eight weeks of regular participation in small-sided soccer games was sufficient to increase aerobic performance and promote health benefits related to similar aerobic training in untrained adult women.
TL and OSL characterization of Eu3+ doped Y2O3: Application in dosimetry
NASA Astrophysics Data System (ADS)
Shivaramu, N. J.; Coetsee, E.; Swart, H. C.
2018-05-01
Thermoluminescence (TL) and optically stimulated luminescence (OSL) properties of beta irradiated Eu3+ doped Y2O3 nanophosphor have been investigated in this paper. The Eu3+ doped Y2O3 nanophosphor was synthesized by solution combustion technique and synthesized material was annealed at 900°C. The annealed materials were exposed to β-ray for various dose. TL glow with prominent peak at 403 K and weak glow peak at 660 K were observed in all irradiated samples. It is found that TL glow peaks intensity linearly increases with increase in β-dose from 8.125 - 40.625 Gy. The TL kinetic parameters were calculated using glow curve deconvoluted (GCD) and peak shape methods. The TL glows exhibits general order kinetics. Intense continuous wave optical stimulated luminescence (CW-OSL) was observed in the sample. These material exhibits linearity at low dose, good reproducibility and response of intense OSL and hence, these results suggests that this material may be suitable for dosimetry applications.
NASA Astrophysics Data System (ADS)
Qiu, Wenyu; Ren, Fumin; Wu, Liguang; Chen, Lianshou; Ding, Chenchen
2018-03-01
Extreme precipitation induced by a tropical cyclone (TC) is of great concern to Southeast China. Regional characteristics of daily TC-induced extreme precipitation (TCEP) between 1958 and 2016 and the associated preliminary causes over Southeast China (Zhejiang, Fujian, and Shanghai) were examined by applying the objective synoptic analysis technique, TC track similarity area index, daily precipitation observations, and reanalysis data. The intensity and frequency of high-intensity TCEP (≥ 100, ≥ 200, ≥ 300 mm) have had an increasing trend over recent decades. Most of TCEP occurs from July to September, with frequency peaks in August for TCEP at all intensity levels, apart from the frequency for TCEP ≥ 300 mm that peaks in September. Regions with high frequency and large TCEP (R-HFLTs) (relatively high frequency for TCEP ≥ 100 mm) were concentrated along the coastline of the southern coastal Fujian (Southern R-HFLT), the regions from northern coastal Fujian to southernmost coastal Zhejiang (Central R-HFLT), and central coastal Zhejiang (Northern R-HFLT), decreasing from the coastline to inland. The Central R-HFLT region had the highest TCEP intensity and frequency for TCEP ≥ 100 mm compared with the other R-HFLTs. Further analysis showed that the special terrain of Southeast China matched the spatial distribution of TCEP, which highlights the significance of the topography of Southeast China. To discover other factors responsible for the heavy TCEP, we compared two TC groups that influence Central R-HFLT. Under a more northerly direction and slow movement combined with the unique terrain, TCs with stronger vortex circulation generated heavier TCEP during landfall in Central R-HFLT. Heavy TCEP occurred with easterly and southeasterly winds interacting with terrain over the eastern coast for Central R-HFLT. Although large changes in the internal and external environment were sensitive to the observed TCEP intensity, the interaction between TC circulation and the complex topography in Southeast China under the northerly track was the dominant factor.
NASA Astrophysics Data System (ADS)
Wang, Lin-Jie; Cheng, Tan; Zhi-Li, Li; Hui-juan, Wang; Wen-juan, Chen; Jianfeng, Zhang; Desheng, Wang; Dongbin, Niu; Qi, Zhao; Chengjia, Yang; Yanqing, Wang
High intensity interval training (HIIT) has been demonstrated to improve performance in a relatively short training period. But the difference between high intensity interval training and moderate intensity interval training (MIIT) in simulated weightlessness still has not been well studied. This study sought to characterize the difference between 6 weeks high intensity interval training and moderate intensity interval training under reduced weight (RW) gait training device and zero-gravity locomotion system (ZLS). Twenty-three subjects (14M/4F, 32.5±4.5 years) volunteered to participate. They were divided into three groups, that were MITT (alternating 2 min at 40% VO _{2} peak and 2 min at 60% VO _{2} peak for 30min, five days per week) RW group (n=8), HITT (alternating 2 min at 40% VO _{2} peak and 2 min at 90% VO _{2} peak for 30min, three days per week) RW group (n=8) and HITT ZLS group (n=7). The Z-axis load used in RW group was 80% body weight (BW) and in ZLS was 100% BW. Cardiopulmonary function was measured before, after 4-week training and after 6-week training. Isokinetic knee extension-flexion test at 60(°) deg/s and 180(°) deg/s were performed before and after the 6-week training, and isometric knee extension-flexion test at 180(°) deg/s was also examined at the same time. It was found that the VO _{2} peaks, metabolic equivalent (MET), Speedmax and respiratory exchange ratio (RER) were significantly increased after 4 and 6-week training in all three groups and no significant group difference were detected. The peak torque at 60(°) deg/s for right knee flexion were significantly increased after 6 week-training in all three groups, and only in HITT RW group the total power at 60(°) deg/s for right knee flexion enhanced. The total power and average power at 60(°) deg/s for right knee extension decreased significantly after 6-week training in all three groups. The peak torque at 60(°) deg/s for right knee extension in MIIT RW group was significantly higher than that in HIIT ZLS group. The maximum average peak torque for isometric left knee contraction was enhanced after 6-week training in all three groups. It was suggested that HITT can be used in weightlessness to maintain the cardiopulmonary function in a relatively short training period, but the effect of HIIT on the maintenance of muscle function still need further study. (Supported by State Key Laboratory Grant NO. SMFA10A04 and The Twelfth Five Year Plan of Medical and Health Research Grant NO. BWS11J055)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tu, C. W.
The focus of this work is to improve the quality of GaInNAs by advanced thin-film growth techniques, such as digital-alloy growth techniques and migration-enhanced epitaxy (MEE). The other focus is to further investigate the properties of such materials, which are potentially beneficial for high-efficiency, multijunction solar cells. 400-nm-thick strain-compensated Ga0.92In0.08As/GaN0.03As0.97 short-period superlattices (SPSLs) are grown lattice-matched to GaAs substrates. The photoluminescence (PL) intensity of digital alloys is 3 times higher than that of random alloys at room temperature, and the improvement is even greater at low temperature, by a factor of about 12. The room-temperature PL intensity of the GaInNAsmore » quantum well grown by the strained InAs/GaN0.023As SPSL growth mode is higher by a factor 5 as compare to the continuous growth mode. The SPSL growth method allows for independent adjustment of the In-to-Ga ratio without group III competition. MEE reduces the low-energy tail of PL, and PL peaks become more intense and sharper. The twin peaks photoluminescence of GaNAs grown on GaAs was observed at room temperature. The peaks splitting increase with increase in nitrogen alloy content. The strain-induced splitting of light-hole and heavy-hole bands of tensile-strained GaNAs is proposed as an explanation of such behavior.« less
A bright attosecond x-ray pulse train generation in a double-laser-driven cone target
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hu, Li-Xiang; Yu, Tong-Pu, E-mail: tongpu@nudt.edu.cn; Shao, Fu-Qiu
By using full three-dimensional particle-in-cell and Monte Carlo simulations, we investigate the generation of a high-brightness attosecond x-ray pulse train in a double-laser-driven cone target. The scheme makes use of two lasers: the first high-intensity laser with a laser peak intensity 1.37 × 10{sup 20 }W/cm{sup 2} irradiates the cone and produces overdense attosecond electron bunches; the second counterpropagating weakly relativistic laser with a laser peak intensity 4.932 × 10{sup 17 }W/cm{sup 2} interacts with the produced electron bunches and a bright x-ray pulse train is generated by Thomson backscattering of the second laser off the attosecond electron bunches. It is shown that the photon fluxmore » rises by 5 times using the cone target as compared with a normal channel. Meanwhile, the x-ray peak brightness increases significantly from 1.4 × 10{sup 21}/(s mm{sup 2} mrad{sup 2} 0.1 keV) to 6.0 × 10{sup 21}/(s mm{sup 2} mrad{sup 2} 0.1 keV), which is much higher than that of the Thomson x-ray source generated from traditional accelerators. We also discuss the influence of the laser and target parameters on the x-ray pulse properties. This compact bright x-ray source may have diverse applications, e.g., the study of electric dynamics and harmonics emission in the atomic scale.« less
Sperlich, Billy; Wallmann-Sperlich, Birgit; Zinner, Christoph; Von Stauffenberg, Valerie; Losert, Helena; Holmberg, Hans-Christer
2017-01-01
The effects of circuit-like functional high-intensity training (Circuit HIIT ) alone or in combination with high-volume low-intensity exercise (Circuit combined ) on selected cardio-respiratory and metabolic parameters, body composition, functional strength and the quality of life of overweight women were compared. In this single-center, two-armed randomized, controlled study, overweight women performed 9-weeks (3 sessions·wk -1 ) of either Circuit HIIT ( n = 11), or Circuit combined ( n = 8). Peak oxygen uptake and perception of physical pain were increased to a greater extent ( p < 0.05) by Circuit HIIT , whereas Circuit combined improved perception of general health more ( p < 0.05). Both interventions lowered body mass, body-mass-index, waist-to-hip ratio, fat mass, and enhanced fat-free mass; decreased ratings of perceived exertion during submaximal treadmill running; improved the numbers of push-ups, burpees, one-legged squats, and 30-s skipping performed, as well as the height of counter-movement jumps; and improved physical and social functioning, role of physical limitations, vitality, role of emotional limitations, and mental health to a similar extent (all p < 0.05). Either forms of these multi-stimulating, circuit-like, multiple-joint training can be employed to improve body composition, selected variables of functional strength, and certain dimensions of quality of life in overweight women. However, Circuit HIIT improves peak oxygen uptake to a greater extent, but with more perception of pain, whereas Circuit combined results in better perception of general health.
Muscle irisin response to aerobic vs HIIT in overweight female adolescents.
Archundia-Herrera, Carolina; Macias-Cervantes, Maciste; Ruiz-Muñoz, Bernardo; Vargas-Ortiz, Katya; Kornhauser, Carlos; Perez-Vazquez, Victoriano
2017-01-01
Exercise stimulates the production of fibronectin type III domain-containing protein 5 (FNDC5), which is cleaved to release a protein called irisin. This protein induces browning of white adipose tissue resulting in increased thermogenesis. Different studies have measured circulating irisin at baseline and in response to exercise among a wide variety of individuals; yet, regarding the effect of different exercise intensities in obese adolescent girls, limited insight is available. This study compares the effect of acute aerobic exercise of moderate intensity and high-intensity interval training (HIIT) on irisin levels in skeletal muscle and plasma of sedentary overweight or obese female adolescents. The aerobic group (n = 15) and HIIT group (n = 15) underwent anthropometric and metabolic measurements, electrocardiogram, peak oxygen uptake (VO 2peak ), and two vastus lateralis muscle biopsies before and after session of workout. The session of aerobic exercise included cycling at 65% of their peak heart rate (HRpeak) for 40 min. In the HIIT group, exercise included six bouts of 1 min at 85-95% HRpeak separated by 1 min of recovery. Irisin levels were evaluated in samples of skeletal muscle (western blot) and plasma (ELISA). The levels of expression of irisin in skeletal muscle increased significantly after a session of HIIT (p < 0.05), while aerobic exercise no affect irisin levels. No significant differences between the groups in plasma irisin levels were found. The increase in muscle irisin levels was observed only following HIIT session. No increases in plasma irisin concentration were observed.
Sperlich, Billy; Wallmann-Sperlich, Birgit; Zinner, Christoph; Von Stauffenberg, Valerie; Losert, Helena; Holmberg, Hans-Christer
2017-01-01
The effects of circuit-like functional high-intensity training (CircuitHIIT) alone or in combination with high-volume low-intensity exercise (Circuitcombined) on selected cardio-respiratory and metabolic parameters, body composition, functional strength and the quality of life of overweight women were compared. In this single-center, two-armed randomized, controlled study, overweight women performed 9-weeks (3 sessions·wk−1) of either CircuitHIIT (n = 11), or Circuitcombined (n = 8). Peak oxygen uptake and perception of physical pain were increased to a greater extent (p < 0.05) by CircuitHIIT, whereas Circuitcombined improved perception of general health more (p < 0.05). Both interventions lowered body mass, body-mass-index, waist-to-hip ratio, fat mass, and enhanced fat-free mass; decreased ratings of perceived exertion during submaximal treadmill running; improved the numbers of push-ups, burpees, one-legged squats, and 30-s skipping performed, as well as the height of counter-movement jumps; and improved physical and social functioning, role of physical limitations, vitality, role of emotional limitations, and mental health to a similar extent (all p < 0.05). Either forms of these multi-stimulating, circuit-like, multiple-joint training can be employed to improve body composition, selected variables of functional strength, and certain dimensions of quality of life in overweight women. However, CircuitHIIT improves peak oxygen uptake to a greater extent, but with more perception of pain, whereas Circuitcombined results in better perception of general health. PMID:28420999
Interval training intensity affects energy intake compensation in obese men.
Alkahtani, Shaea A; Byrne, Nuala M; Hills, Andrew P; King, Neil A
2014-12-01
Compensatory responses may attenuate the effectiveness of exercise training in weight management. The aim of this study was to compare the effect of moderate- and high-intensity interval training on eating behavior compensation. Using a crossover design, 10 overweight and obese men participated in 4-week moderate (MIIT) and high (HIIT) intensity interval training. MIIT consisted of 5-min cycling stages at ± 20% of mechanical work at 45%VO(2)peak, and HIIT consisted of alternate 30-s work at 90%VO(2)peak and 30-s rests, for 30 to 45 min. Assessments included a constant-load exercise test at 45%VO(2)peak for 45 min followed by 60-min recovery. Appetite sensations were measured during the exercise test using a Visual Analog Scale. Food preferences (liking and wanting) were assessed using a computer-based paradigm, and this paradigm uses 20 photographic food stimuli varying along two dimensions, fat (high or low) and taste (sweet or nonsweet). An ad libitum test meal was provided after the constant-load exercise test. Exercise-induced hunger and desire to eat decreased after HIIT, and the difference between MIIT and HIIT in desire to eat approached significance (p = .07). Exercise-induced liking for high-fat nonsweet food tended to increase after MIIT and decreased after HIIT (p = .09). Fat intake decreased by 16% after HIIT, and increased by 38% after MIIT, with the difference between MIIT and HIIT approaching significance (p = .07). This study provides evidence that energy intake compensation differs between MIIT and HIIT.
Magnetic location of C IV events in the quiet network
NASA Technical Reports Server (NTRS)
Porter, Jason G.; Reichmann, Ed J.; Moore, Ronald L.; Harvey, Karen L.
1986-01-01
Ultraviolet Spectrograph and Polarimeter (UVSP) observations of C IV intensity in the quiet sun were examined and compared to magnetograms and He I 10830 A spectroheliograms from Kitt Peak National Laboratory. The observations were made between 3 and 9 April, 1985. Spatially rastered UVSP intensity measurements were obtained at 11 wavelength positions in the 1548 A line of C IV. It was concluded that the stochastic process whereby convective shuffling of loop footprints leads to many topically dissipative events in active regions and the larger bipoles treated here continues to operate in regions of fewer, weaker flux loops, but the resulting events above threshold are less frequent.
NASA Astrophysics Data System (ADS)
Bertie, John E.; Michaelian, Kirk H.
1998-10-01
This paper is concerned with the peak wave number of very strong absorption bands in infrared spectra of molecular liquids. It is well known that the peak wave number can differ depending on how the spectrum is measured. It can be different, for example, in a transmission spectrum and in an attenuated total reflection spectrum. This difference can be removed by transforming both spectra to the real, n, and imaginary, k, refractive index spectra, because both spectra yield the same k spectrum. However, the n and k spectra can be transformed to spectra of any other intensity quantity, and the peak wave numbers of strong bands may differ by up to 6 cm-1 in the spectra of the different quantities. The question which then arises is "which infrared peak wave number is the correct one to use in the comparison of infrared wave numbers of molecular liquids with wave numbers in other spectra?" For example, infrared wave numbers in the gas and liquid phase are compared to observe differences between the two phases. Of equal importance, the wave numbers of peaks in infrared and Raman spectra of liquids are compared to determine whether the infrared-active and Raman-active vibrations coincide, and thus are likely to be the same, or are distinct. This question is explored in this paper by presenting the experimental facts for different intensity quantities. The intensity quantities described are macroscopic properties of the liquid, specifically the absorbance, attenuated total reflectance, imaginary refractive index, k, imaginary dielectric constant, ɛ″, and molar absorption coefficient, Em, and one microscopic property of a molecule in the liquid, specifically the imaginary molar polarizability, αm″, which is calculated under the approximation of the Lorentz local field. The main experimental observations are presented for the strongest band in the infrared spectrum of each of the liquids methanol, chlorobenzene, dichloromethane, and acetone. Particular care was paid to wave number calibration of both infrared and Raman spectra. Theoretical arguments indicate that the peak wave number in the αm″ spectrum is the correct one to use, because it is the only one that reflects the properties of molecules in their local environment in the liquid free from predictable long-range resonant dielectric effects. However, it is found that the comparison with Raman wave numbers is confused when the anisotropic local intermolecular forces and configuration in the liquid are significant. In these cases, the well known noncoincidence of the isotropic and anisotropic Raman scattering is observed, and the same factors lead to noncoincidence of the infrared and Raman bands.
Staley, Dennis; Kean, Jason W.; Cannon, Susan H.; Schmidt, Kevin M.; Laber, Jayme L.
2012-01-01
Rainfall intensity–duration (ID) thresholds are commonly used to predict the temporal occurrence of debris flows and shallow landslides. Typically, thresholds are subjectively defined as the upper limit of peak rainstorm intensities that do not produce debris flows and landslides, or as the lower limit of peak rainstorm intensities that initiate debris flows and landslides. In addition, peak rainstorm intensities are often used to define thresholds, as data regarding the precise timing of debris flows and associated rainfall intensities are usually not available, and rainfall characteristics are often estimated from distant gauging locations. Here, we attempt to improve the performance of existing threshold-based predictions of post-fire debris-flow occurrence by utilizing data on the precise timing of debris flows relative to rainfall intensity, and develop an objective method to define the threshold intensities. We objectively defined the thresholds by maximizing the number of correct predictions of debris flow occurrence while minimizing the rate of both Type I (false positive) and Type II (false negative) errors. We identified that (1) there were statistically significant differences between peak storm and triggering intensities, (2) the objectively defined threshold model presents a better balance between predictive success, false alarms and failed alarms than previous subjectively defined thresholds, (3) thresholds based on measurements of rainfall intensity over shorter duration (≤60 min) are better predictors of post-fire debris-flow initiation than longer duration thresholds, and (4) the objectively defined thresholds were exceeded prior to the recorded time of debris flow at frequencies similar to or better than subjective thresholds. Our findings highlight the need to better constrain the timing and processes of initiation of landslides and debris flows for future threshold studies. In addition, the methods used to define rainfall thresholds in this study represent a computationally simple means of deriving critical values for other studies of nonlinear phenomena characterized by thresholds.
The oxygen uptake slow component at submaximal intensities in breaststroke swimming
Oliveira, Diogo R.; Gonçalves, Lio F.; Reis, António M.; Fernandes, Ricardo J.; Garrido, Nuno D.
2016-01-01
Abstract The present work proposed to study the oxygen uptake slow component (VO2 SC) of breaststroke swimmers at four different intensities of submaximal exercise, via mathematical modeling of a multi-exponential function. The slow component (SC) was also assessed with two different fixed interval methods and the three methods were compared. Twelve male swimmers performed a test comprising four submaximal 300 m bouts at different intensities where all expired gases were collected breath by breath. Multi-exponential modeling showed values above 450 ml·min−1 of the SC in the two last bouts of exercise (those with intensities above the lactate threshold). A significant effect of the method that was used to calculate the VO2 SC was revealed. Higher mean values were observed when using mathematical modeling compared with the fixed interval 3rd min method (F=7.111; p=0.012; η2=0.587); furthermore, differences were detected among the two fixed interval methods. No significant relationship was found between the SC determined by any method and the blood lactate measured at each of the four exercise intensities. In addition, no significant association between the SC and peak oxygen uptake was found. It was concluded that in trained breaststroke swimmers, the presence of the VO2 SC may be observed at intensities above that corresponding to the 3.5 mM-1 threshold. Moreover, mathematical modeling of the oxygen uptake on-kinetics tended to show a higher slow component as compared to fixed interval methods. PMID:28149379
Infection-Mediated Vasoactive Peptides Modulate Cochlear Uptake of Fluorescent Gentamicin
Koo, Ja-Won; Wang, Qi; Steyger, Peter S.
2011-01-01
Inflammatory mediators released during bacterial infection include vasoactive peptides such as histamine and serotonin, and their serum levels are frequently elevated. These peptides also modulate the vascular permeability of endothelial cells lining the blood-brain and blood-labyrinth barriers (BLB). These peptides may also modulate the permeability of the BLB to ototoxic aminoglycoside antibiotics prescribed to resolve bacterial sepsis. To test this hypothesis, we compared the effect of histamine and serotonin on the cochlear distribution of fluorescently conjugated gentamicin (GTTR) in control animals at 0.5, 1 and 3 h after injection of GTTR. The intensity of GTTR fluorescence was attenuated at 1 h in the histamine group compared to control mice, and more intense 3 h after injection (p < 0.05). In the serotonin group, the intensity of GTTR fluorescence was attenuated at 0.5 and 1 h (p < 0.05) and was increased at 3 h compared to control animals, where GTTR intensities peaked at 1 h and then plateaued or was slightly decreased at 3 h. This biphasic pattern of modulation was statistically significant in the apical turn of the cochlea. No difference in the intensity of GTTR fluorescence was observed in kidney proximal tubules. Systemic increases in serum levels of vasoactive peptides can modulate cochlear uptake of gentamicin, likely via permeability changes in the BLB. Conditions that influence serum levels of vasoactive peptides may potentiate aminoglycoside ototoxicity. PMID:21196726
A peak position comparison method for high-speed quantitative Laue microdiffraction data processing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kou, Jiawei; Chen, Kai; Tamura, Nobumichi
Indexing Laue patterns of a synchrotron microdiffraction scan can take as much as ten times longer than collecting the data, impeding efficient structural analysis using this technique. Here in this paper, a novel strategy is developed. By comparing the peak positions of adjacent Laue patterns and checking the intensity sequence, grain and phase boundaries are identified, requiring only a limited number of indexing steps for each individual grain. Using this protocol, the Laue patterns can be indexed on the fly as they are taken. The validation of this method is demonstrated by analyzing the microstructure of a laser 3D printedmore » multi-phase/multi-grain Ni-based superalloy.« less
A peak position comparison method for high-speed quantitative Laue microdiffraction data processing
Kou, Jiawei; Chen, Kai; Tamura, Nobumichi
2018-09-12
Indexing Laue patterns of a synchrotron microdiffraction scan can take as much as ten times longer than collecting the data, impeding efficient structural analysis using this technique. Here in this paper, a novel strategy is developed. By comparing the peak positions of adjacent Laue patterns and checking the intensity sequence, grain and phase boundaries are identified, requiring only a limited number of indexing steps for each individual grain. Using this protocol, the Laue patterns can be indexed on the fly as they are taken. The validation of this method is demonstrated by analyzing the microstructure of a laser 3D printedmore » multi-phase/multi-grain Ni-based superalloy.« less
The LaueUtil toolkit for Laue photocrystallography. II. Spot finding and integration
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kalinowski, Jaroslaw A.; Fournier, Bertrand; Makal, Anna
2015-10-15
A spot-integration method is described which does not require prior indexing of the reflections. It is based on statistical analysis of the values from each of the pixels on successive frames, followed for each frame by morphological analysis to identify clusters of high value pixels which form an appropriate mask corresponding to a reflection peak. The method does not require prior assumptions such as fitting of a profile or definition of an integration box. The results are compared with those of the seed-skewness method which is based on minimizing the skewness of the intensity distribution within a peak's integration box.more » Applications in Laue photocrystallography are presented.« less
Fly's eye condenser based on chirped microlens arrays
NASA Astrophysics Data System (ADS)
Wippermann, Frank C.; Zeitner, Uwe-D.; Dannberg, Peter; Bräuer, Andreas; Sinzinger, Stefan
2007-09-01
Lens array arrangements are commonly used for the beam shaping of almost arbitrary input intensity distributions into a top-hat. The setup usually consists of a Fourier lens and two identical regular microlens arrays - often referred to as tandem lens array - where the second one is placed in the focal plane of the first microlenses. Due to the periodic structure of regular arrays the output intensity distribution is modulated by equidistant sharp intensity peaks which are disturbing the homogeneity. The equidistantly located intensity peaks can be suppressed when using a chirped and therefore non-periodic microlens array. A far field speckle pattern with more densely and irregularly located intensity peaks results leading to an improved homogeneity of the intensity distribution. In contrast to stochastic arrays, chirped arrays consist of individually shaped lenses defined by a parametric description of the cells optical function which can be derived completely from analytical functions. This gives the opportunity to build up tandem array setups enabling to achieve far field intensity distribution with an envelope of a top-hat. We propose a new concept for fly's eye condensers incorporating a chirped tandem microlens array for the generation of a top-hat far field intensity distribution with improved homogenization under coherent illumination. The setup is compliant to reflow of photoresist as fabrication technique since plane substrates accommodating the arrays are used. Considerations for the design of the chirped microlens arrays, design rules, wave optical simulations and measurements of the far field intensity distributions are presented.
Dall, C H; Snoer, M; Christensen, S; Monk-Hansen, T; Frederiksen, M; Gustafsson, F; Langberg, H; Prescott, E
2014-10-01
In heart transplant (HTx) recipients, there has been reluctance to recommend high-intensity interval training (HIIT) due to denervation and chronotropic impairment of the heart. We compared the effects of 12 weeks' HIIT versus continued moderate exercise (CON) on exercise capacity and chronotropic response in stable HTx recipients >12 months after transplantation in a randomized crossover trial. The study was completed by 16 HTx recipients (mean age 52 years, 75% males). Baseline peak oxygen uptake (VO2peak ) was 22.9 mL/kg/min. HIIT increased VO2peak by 4.9 ± 2.7 mL/min/kg (17%) and CON by 2.6 ± 2.2 mL/kg/min (10%) (significantly higher in HIIT; p < 0.001). During HIIT, systolic blood pressure decreased significantly (p = 0.037) with no significant change in CON (p = 0.241; between group difference p = 0.027). Peak heart rate (HRpeak ) increased significantly by 4.3 beats per minute (p = 0.014) after HIIT with no significant change in CON (p = 0.34; between group difference p = 0.027). Heart rate recovery (HRrecovery ) improved in both groups with a trend toward greater improvement after HIIT. The 5-month washout showed a significant loss of improvement. HIIT was well tolerated, had a superior effect on oxygen uptake, and led to an unexpected increase in HRpeak accompanied by a faster HRrecovery . This indicates that the benefits of HIIT are partly a result of improved chronotropic response. © Copyright 2014 The American Society of Transplantation and the American Society of Transplant Surgeons.
Robinson, Matthew M; Lowe, Val J; Nair, K Sreekumaran
2018-01-01
Aerobic exercise training can increase brain volume and blood flow, but the impact on brain metabolism is less known. We determined whether high-intensity interval training (HIIT) increases brain metabolism by measuring brain glucose uptake in younger and older adults. Brain glucose uptake was measured before and after HIIT or a sedentary (SED) control period within a larger exercise study. Study procedures were performed at the Mayo Clinic in Rochester, MN. Participants were younger (18 to 30 years) or older (65 to 80 years) SED adults who were free of major medical conditions. Group sizes were 15 for HIIT (nine younger and six older) and 12 for SED (six younger and six older). Participants completed 12 weeks of HIIT or SED. HIIT was 3 days per week of 4 × 4 minute intervals at over 90% of peak aerobic capacity (VO2peak) with 2 days per week of treadmill walking at 70% VO2peak. Resting brain glucose uptake was measured using 18F-fluorodeoxyglucose positron emission tomography scans at baseline and at week 12. Scans were performed at 96 hours after exercise. VO2peak was measured by indirect calorimetry. Glucose uptake increased significantly in the parietal-temporal and caudate regions after HIIT compared with SED. The gains with HIIT were not observed in all brain regions. VO2peak was increased for all participants after HIIT and did not change with SED. We demonstrate that brain glucose metabolism increased after 12 weeks of HIIT in adults in regions where it is reduced in Alzheimer's disease. Copyright © 2017 Endocrine Society
Miyaji, Kagami; Miyamoto, Takashi; Kohira, Satoshi; Itatani, Kei-ichi; Tomoyasu, Takahiro; Sato, Hajime; Ohara, Kuniyoshi
2010-06-01
Since 2007, the Japanese Red Cross Blood Center has provided prestorage leukocyte-reduced red blood cell concentrates in which the leukocytes were reduced soon after collection. We have established a miniaturized bypass system (140 mL) to reduce the perioperative inflammatory responses. This study was designed to reveal the effectiveness of leukocyte-reduced red blood cell concentrate transfusion on perioperative inflammatory responses in pediatric cardiac surgery. Between May 2006 and June 2008, 50 consecutive patients weighing less than 5 kg who underwent a surgical procedure with red blood cell concentrate transfusion using a miniaturized bypass system were reviewed retrospectively. Twenty-five patients before 2007 received stored red blood cell concentrate in which leukocytes were reduced with a filter just before transfusion (group A). After 2007, 25 patients received the prestorage leukocyte-reduced red blood cell concentrate transfusion (group B). The postoperative peak C-reactive protein level, peak white blood cell count, peak neutrophil count, percentage body weight gain, inotrope score, plasma lactate concentration, postoperative mechanical ventilation time, and length of intensive care unit stay were compared as the perioperative inflammatory response and morbidity for both groups. There were no significant differences in peak white blood cell count, peak neutrophil count, percentage body weight gain, and inotrope score between the groups. The peak C-reactive protein level in group A was significantly greater than that in group B (6.7 +/- 4.7 vs 4.2 +/- 3.6 mg/dL, P < .05). The lactate concentration at 12 and 24 hours after surgical intervention in group A was significantly greater than that in group B (3.1 +/- 2.5 vs 1.9 +/- 1.1 mmol/L [P < .05] and 2.2 +/- 0.2 vs 1.4 +/- 0.2 mmol/L [P < .05], respectively). The postoperative mechanical ventilation time and intensive care unit stay in group A were significantly greater than those in group B (5.9 +/- 7.4 vs 2.1 +/- 2.0 days [P < .05] and 9.8 +/- 7.9 vs 5.0 +/- 2.1 days [P < 0.05], respectively). Multivariate analyses showed that the leukocyte-reduced red blood cell concentrate transfusion reduced the peak C-reactive protein level (in milligrams per deciliter; coefficient, -2.95; 95% confidence interval [CI], -4.66 to -0.93; P = .003), postoperative mechanical ventilation time (in days; coefficient, -3.41; 95% CI, -6.07 to -0.74; P = .013), and intensive care unit stay (in days; coefficient, -4.51; 95% CI, -7.37 to -1.64; P = .003). Our study revealed that in neonates and small infants, compared with transfusions with stored red blood cell concentrate, transfusion of leukocyte-reduced red blood cell concentrates was associated with reduced perioperative inflammatory responses and improved clinical outcomes. Copyright 2010 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.
Relating Convective and Stratiform Rain to Latent Heating
NASA Technical Reports Server (NTRS)
Tao, Wei-Kuo; Lang, Stephen; Zeng, Xiping; Shige, Shoichi; Takayabu, Yukari
2010-01-01
The relationship among surface rainfall, its intensity, and its associated stratiform amount is established by examining observed precipitation data from the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR). The results show that for moderate-high stratiform fractions, rain probabilities are strongly skewed toward light rain intensities. For convective-type rain, the peak probability of occurrence shifts to higher intensities but is still significantly skewed toward weaker rain rates. The main differences between the distributions for oceanic and continental rain are for heavily convective rain. The peak occurrence, as well as the tail of the distribution containing the extreme events, is shifted to higher intensities for continental rain. For rainy areas sampled at 0.58 horizontal resolution, the occurrence of conditional rain rates over 100 mm/day is significantly higher over land. Distributions of rain intensity versus stratiform fraction for simulated precipitation data obtained from cloud-resolving model (CRM) simulations are quite similar to those from the satellite, providing a basis for mapping simulated cloud quantities to the satellite observations. An improved convective-stratiform heating (CSH) algorithm is developed based on two sources of information: gridded rainfall quantities (i.e., the conditional intensity and the stratiform fraction) observed from the TRMM PR and synthetic cloud process data (i.e., latent heating, eddy heat flux convergence, and radiative heating/cooling) obtained from CRM simulations of convective cloud systems. The new CSH algorithm-derived heating has a noticeably different heating structure over both ocean and land regions compared to the previous CSH algorithm. Major differences between the new and old algorithms include a significant increase in the amount of low- and midlevel heating, a downward emphasis in the level of maximum cloud heating by about 1 km, and a larger variance between land and ocean in the new CSH algorithm.
49 CFR 229.125 - Headlights and auxiliary lights.
Code of Federal Regulations, 2014 CFR
2014-10-01
... produce a peak intensity of at least 200,000 candela and produce at least 3,000 candela at an angle of 7.5... regularly required to run backward for any portion of its trip other than to pick up a detached portion of... produce a peak intensity of at least 200,000 candela and shall produce at least 3,000 candela at an angle...
49 CFR 229.125 - Headlights and auxiliary lights.
Code of Federal Regulations, 2013 CFR
2013-10-01
... produce a peak intensity of at least 200,000 candela and produce at least 3,000 candela at an angle of 7.5... regularly required to run backward for any portion of its trip other than to pick up a detached portion of... produce a peak intensity of at least 200,000 candela and shall produce at least 3,000 candela at an angle...
Study on the application of Raman spectroscopy on detecting water hardness.
Yang, Chang-Hu; Shi, Xiang-Hua; Yuan, Jian-Hui
2014-05-01
Laser Raman spectrum method was used to study the hardness index of four water samples. The ratio of bending vibration peak intensity to stretching vibration peak intensity of these water samples was measured. The results showed that as the total hardness of water decreases, so does the ratio. This offers a possible new approach to water quality analysis that is both simple and effective.
Kim, Jeehyun; Kim, Jung Hoon; Yoon, Soon Ho; Choi, Won Seok; Kim, Young Jae; Han, Joon Koo; Choi, Byung-Ihn
2015-12-01
The aim of this study was to assess the feasibility of using dynamic contrast-enhanced ultrasound (DCE-US) with a 3-D transducer to evaluate therapeutic responses to targeted therapy. Rabbits with hepatic VX2 carcinomas, divided into a treatment group (n = 22, 30 mg/kg/d sorafenib) and a control group (n = 13), were evaluated with DCE-US using 2-D and 3-D transducers and computed tomography (CT) perfusion imaging at baseline and 1 d after the first treatment. Perfusion parameters were collected, and correlations between parameters were analyzed. In the treatment group, both volumetric and 2-D DCE-US perfusion parameters, including peak intensity (33.2 ± 19.9 vs. 16.6 ± 10.7, 63.7 ± 20.0 vs. 30.1 ± 19.8), slope (15.3 ± 12.4 vs. 5.7 ± 4.5, 37.3 ± 20.4 vs. 15.7 ± 13.0) and area under the curve (AUC; 1004.1 ± 560.3 vs. 611.4 ± 421.1, 1332.2 ± 708.3 vs. 670.4 ± 388.3), had significantly decreased 1 d after the first treatment (p = 0.00). In the control group, 2-D DCE-US revealed that peak intensity, time to peak and slope had significantly changed (p < 0.05); however, volumetric DCE-US revealed that peak intensity, time-intensity AUC, AUC during wash-in and AUC during wash-out had significantly changed (p = 0.00). CT perfusion imaging parameters, including blood flow, blood volume and permeability of the capillary vessel surface, had significantly decreased in the treatment group (p = 0.00); however, in the control group, peak intensity and blood volume had significantly increased (p = 0.00). It is feasible to use DCE-US with a 3-D transducer to predict early therapeutic response after targeted therapy because perfusion parameters, including peak intensity, slope and AUC, significantly decreased, which is similar to the trend observed for 2-D DCE-US and CT perfusion imaging parameters. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.
Sandbakk, Øyvind; Rasdal, Vegard; Bråten, Steinar; Moen, Frode; Ettema, Gertjan
2016-10-01
To compare sport-specific laboratory capacities and the annual training of world-class Nordic combined (NC) athletes with specialized ski jumpers (SJ) and cross-country (XC) skiers. Five world-class athletes from each sports discipline were compared. Ski jump imitations were performed on a 3-dimensional force plate in NC athletes and SJ, whereas XC skiing characteristics were obtained from submaximal and maximal roller ski skating on a treadmill in NC athletes and XC skiers. In addition, anthropometrics and annual training characteristics were determined. NC athletes demonstrated 9% higher body mass and showed 17% lower vertical speed in the ski jump imitation than SJ (all P < .05). NC athletes had 12% lower body mass and showed 10% lower peak treadmill speed and 12% lower body-mass-normalized peak oxygen uptake than XC skiers (all P < .05). NC athletes performed half the number of ski-jumping-specific sessions and outdoor ski jumps compared with SJ. NC athletes performed 31% less endurance training, mainly caused by lower amounts of low- and moderate-intensity training in the classical technique, whereas high-intensity strength and speed training and endurance training in the skating technique did not differ substantially from XC skiers. To simultaneously optimize endurance, explosive, and technical capacities in 2 different disciplines, world-class NC athletes train approximately two-thirds of the XC skier's endurance training volume and perform one-half of the ski-jump-specific training compared with SJ. Still, the various laboratory capacities differed only 10-17% compared with SJ and XC skiers.
Fisher, Gordon; Brown, Andrew W; Bohan Brown, Michelle M; Alcorn, Amy; Noles, Corey; Winwood, Leah; Resuehr, Holly; George, Brandon; Jeansonne, Madeline M; Allison, David B
2015-01-01
To compare the effects of six weeks of high intensity interval training (HIIT) vs continuous moderate intensity training (MIT) for improving body composition, insulin sensitivity (SI), blood pressure, blood lipids, and cardiovascular fitness in a cohort of sedentary overweight or obese young men. We hypothesized that HIIT would result in similar improvements in body composition, cardiovascular fitness, blood lipids, and SI as compared to the MIT group, despite requiring only one hour of activity per week compared to five hours per week for the MIT group. 28 sedentary overweight or obese men (age, 20 ± 1.5 years, body mass index 29.5 ± 3.3 kg/m2) participated in a six week exercise treatment. Participants were randomly assigned to HIIT or MIT and evaluated at baseline and post-training. DXA was used to assess body composition, graded treadmill exercise test to measure cardiovascular fitness, oral glucose tolerance to measure SI, nuclear magnetic resonance spectroscopy to assess lipoprotein particles, and automatic auscultation to measure blood pressure. A greater improvement in VO2peak was observed in MIT compared to HIIT (11.1% vs 2.83%, P = 0.0185) in the complete-case analysis. No differences were seen in the intention to treat analysis, and no other group differences were observed. Both exercise conditions were associated with temporal improvements in % body fat, total cholesterol, medium VLDL, medium HDL, triglycerides, SI, and VO2peak (P < 0.05). Participation in HIIT or MIT exercise training displayed: 1) improved SI, 2) reduced blood lipids, 3) decreased % body fat, and 4) improved cardiovascular fitness. While both exercise groups led to similar improvements for most cardiometabolic risk factors assessed, MIT led to a greater improvement in overall cardiovascular fitness. Overall, these observations suggest that a relatively short duration of either HIIT or MIT training may improve cardiometabolic risk factors in previously sedentary overweight or obese young men, with no clear advantage between these two specific regimes (Clinical Trial Registry number NCT01935323). ClinicalTrials.gov NCT01935323.
Fisher, Gordon; Brown, Andrew W.; Bohan Brown, Michelle M.; Alcorn, Amy; Noles, Corey; Winwood, Leah; Resuehr, Holly; George, Brandon; Jeansonne, Madeline M.; Allison, David B.
2015-01-01
Purpose To compare the effects of six weeks of high intensity interval training (HIIT) vs continuous moderate intensity training (MIT) for improving body composition, insulin sensitivity (SI), blood pressure, blood lipids, and cardiovascular fitness in a cohort of sedentary overweight or obese young men. We hypothesized that HIIT would result in similar improvements in body composition, cardiovascular fitness, blood lipids, and SI as compared to the MIT group, despite requiring only one hour of activity per week compared to five hours per week for the MIT group. Methods 28 sedentary overweight or obese men (age, 20 ± 1.5 years, body mass index 29.5 ± 3.3 kg/m2) participated in a six week exercise treatment. Participants were randomly assigned to HIIT or MIT and evaluated at baseline and post-training. DXA was used to assess body composition, graded treadmill exercise test to measure cardiovascular fitness, oral glucose tolerance to measure SI, nuclear magnetic resonance spectroscopy to assess lipoprotein particles, and automatic auscultation to measure blood pressure. Results A greater improvement in VO2peak was observed in MIT compared to HIIT (11.1% vs 2.83%, P = 0.0185) in the complete-case analysis. No differences were seen in the intention to treat analysis, and no other group differences were observed. Both exercise conditions were associated with temporal improvements in % body fat, total cholesterol, medium VLDL, medium HDL, triglycerides, SI, and VO2peak (P < 0.05). Conclusion Participation in HIIT or MIT exercise training displayed: 1) improved SI, 2) reduced blood lipids, 3) decreased % body fat, and 4) improved cardiovascular fitness. While both exercise groups led to similar improvements for most cardiometabolic risk factors assessed, MIT led to a greater improvement in overall cardiovascular fitness. Overall, these observations suggest that a relatively short duration of either HIIT or MIT training may improve cardiometabolic risk factors in previously sedentary overweight or obese young men, with no clear advantage between these two specific regimes (Clinical Trial Registry number NCT01935323). Trial Registration ClinicalTrials.gov NCT01935323 PMID:26489022
HEAO 1 high-energy X-ray observations of Centaurus X-3
NASA Technical Reports Server (NTRS)
Howe, S. K.; Primini, F. A.; Bautz, M. W.; Lang, F. L.; Levine, A. M.; Lewin, W. H. G.
1983-01-01
Pulsations of 4.8 sec were detected up to energies above 38 keV by the present High Energy X-ray and Low Energy Gamma-Ray HEAO 1 satellite experiment observations of Cen X-3, and an analysis of the X-ray spectrum as a function of pulse phase indicates that the spectrum hardens during an interval of about 1.2 sec which lags the pulse peak by about 0.6 sec. The results of correlated observations of pulse period and X-ray intensity include (1) the detection of a high intensity state during which the pulse period is on the average increasing, (2) the measurement of comparable high intensities during episodes of both period increase and decrease, (3) the detection of X-ray pulsations at a much reduced level during a period of low intensity, and (4) the detection of a transition between spin-down, and spin-up episodes that coincides with a rapid decrease in X-ray intensity.
Tsai, Hsing-Hua; Lin, Chin-Pu; Lin, Yi-Hui; Hsu, Chih-Chin; Wang, Jong-Shyan
2016-12-01
Exercise training improves endothelium-dependent vasodilation, whereas hypoxic stress causes vascular endothelial dysfunction. Monocyte-derived endothelial progenitor cells (Mon-EPCs) contribute to vascular repair process by differentiating into endothelial cells. This study investigates how high-intensity interval (HIT) and moderate-intensity continuous (MCT) exercise training affect circulating Mon-EPC levels and EPC functionality under hypoxic condition. Sixty healthy sedentary males were randomized to engage in either HIT (3-min intervals at 40 and 80 % VO 2max for five repetitions, n = 20) or MCT (sustained 60 % VO 2max , n = 20) for 30 min/day, 5 days/week for 6 weeks, or to a control group (CTL) that did not received exercise intervention (n = 20). Mon-EPC characteristics and EPC functionality under hypoxic exercise (HE, 100 W under 12 % O 2 ) were determined before and after HIT, MCT, and CTL. The results demonstrated that after the intervention, the HIT group exhibited larger improvements in VO 2peak , estimated peak cardiac output (Q C ), and estimated peak perfusions of frontal cerebral lobe (Q FC ) and vastus lateralis (Q VL ) than the MCT group. Furthermore, HIT (a) increased circulating CD14 ++ /CD16 - /CD34 + /KDR + (Mon-1 EPC) and CD14 ++ /CD16 + /CD34 + /KDR + (Mon-2 EPC) cell counts, (b) promoted the migration and tube formation of EPCs, (c) diminished the shedding of endothelial (CD34 - /KDR + /phosphatidylserine + ) cells, and (d) elevated plasma nitrite plus nitrate, stromal cell-derived factor-1, matrix metalloproteinase-9, and vascular endothelial growth factor-A concentrations at rest or following HE, compared to those of MCT. In addition, Mon-1 and -2 EPC counts were directly related to VO 2peak and estimated peak Q C , Q FC , and Q VL . HIT is superior to MCT for improving hemodynamic adaptation and Mon-EPC production. Moreover, HIT effectively enhances EPC functionality and suppresses endothelial injury undergoing hypoxia.
Peak wavelength shifts and opponent color theory
NASA Astrophysics Data System (ADS)
Ashdown, Ian; Salsbury, Marc
2007-09-01
We adapt the tenets of Hering's opponent color theory to the processing of data obtained from a tristimulus colorimeter to independently determine the intensity and possible peak wavelength shift of a narrowband LED. This information may then be used for example in an optical feedback loop to maintain constant intensity and chromaticity for a light source consisting of two LEDs with different peak wavelengths. This approach is particularly useful for LED backlighting of LCD display panels using red, green, and blue LEDs, wherein a tristimulus colorimeter can be used to maintain primary chromaticities to within broadcast standard limits in real time.
Gough, Lewis A; Rimmer, Steven; Osler, Callum J; Higgins, Matthew F
2017-10-01
This study evaluated the ingestion of sodium bicarbonate (NaHCO 3 ) on postexercise acid-base balance recovery kinetics and subsequent high-intensity cycling time to exhaustion. In a counterbalanced, crossover design, nine healthy and active males (age: 23 ± 2 years, height: 179 ± 5 cm, body mass: 74 ± 9 kg, peak mean minute power (W peak ) 256 ± 45 W, peak oxygen uptake (V̇O 2peak ) 46 ± 8 ml.kg -1 .min -1 ) performed a graded incremental exercise test, two familiarization and two experimental trials. Experimental trials consisted of cycling to volitional exhaustion (T LIM1 ) at 100% W PEAK on two occasions (T LIM1 and T LIM2 ) interspersed by a 90 min passive recovery period. Using a double-blind approach, 30 min into a 90 min recovery period participants ingested either 0.3 g.kg -1 body mass sodium bicarbonate (NaHCO 3 ) or a placebo (PLA) containing 0.1 g.kg -1 body mass sodium chloride (NaCl) mixed with 4 ml.kg -1 tap water and 1 ml.kg -1 orange squash. The mean differences between T LIM2 and T LIM1 was larger for PLA compared with NaHCO 3 (-53 ± 53 vs. -20 ± 48 s; p = .008, d = 0.7, CI =-0.3, 1.6), indicating superior subsequent exercise time to exhaustion following NaHCO 3 . Blood lactate [Bla - ] was similar between treatments post T LIM1 , but greater for NaHCO 3 post T LIM2 and 5 min post T LIM2 . Ingestion of NaHCO 3 induced marked increases (p < .01) in both blood pH (+0.07 ± 0.02, d = 2.6, CI = 1.2, 3.7) and bicarbonate ion concentration [HCO 3 - ] (+6.8 ± 1.6 mmo.l -1 , d = 3.4, CI = 1.8, 4.7) compared with the PLA treatment, before T LIM2 . It is likely both the acceleration of recovery, and the marked increases of acid-base after T LIM1 contributed to greater T LIM2 performance compared with the PLA condition.
Gucsik, Arnold; Nishido, Hirotsugu; Ninagawa, Kiyotaka; Ott, Ulrich; Tsuchiyama, Akira; Kayama, Masahiro; Simonia, Irakli; Boudou, Jean-Paul
2012-12-01
Color centers in selected micro- and nanodiamond samples were investigated by cathodoluminescence (CL) microscopy and spectroscopy at 298 K [room temperature (RT)] and 77 K [liquid-nitrogen temperature (LNT)] to assess the value of the technique for astrophysics. Nanodiamonds from meteorites were compared with synthetic diamonds made with different processes involving distinct synthesis mechanisms (chemical vapor deposition, static high pressure high temperature, detonation). A CL emission peak centered at around 540 nm at 77 K was observed in almost all of the selected diamond samples and is assigned to the dislocation defect with nitrogen atoms. Additional peaks were identified at 387 and 452 nm, which are related to the vacancy defect. In general, peak intensity at LNT at the samples was increased in comparison to RT. The results indicate a clear temperature-dependence of the spectroscopic properties of diamond. This suggests the method is a useful tool in laboratory astrophysics.
Detection of Scopolamine Hydrobromide via Surface-enhanced Raman Spectroscopy.
Bao, Lin; Sha, Xuan-Yu; Zhao, Hang; Han, Si-Qin-Gao-Wa; Hasi, Wu-Li-Ji
2017-01-01
Surface-enhanced Raman spectroscopy (SERS) was used to measure scopolamine hydrobromide. First, the Raman characteristic peaks of scopolamine hydrobromide were assigned, and the characteristic peaks were determined. The optimal aggregation agent was potassium iodide based on a comparative experimental study. Finally, the SERS spectrum of scopolamine hydrobromide was detected in aqueous solution, and the semi-quantitative analysis and the recovery rate were determined via a linear fitting. The detection limit of scopolamine hydrobromide in aqueous solution was 0.5 μg/mL. From 0 - 10 μg/mL, the curve of the intensity of the Raman characteristic peak of scopolamine hydrobromide at 1002 cm -1 is y = 4017.76 + 642.47x. The correlation coefficient was R 2 = 0.983, the recovery was 98.5 - 109.7%, and the relative standard deviation (RSD) was about 5.5%. This method is fast, accurate, non-destructive and simple for the detection of scopolamine hydrobromide.
Périard, Julien D; Racinais, Sébastien
2015-05-15
This study examined the time course and extent of decrease in peak oxygen uptake (V̇O2peak) during self-paced exercise in HOT (35°C and 60% relative humidity) and COOL (18°C and 40% relative humidity) laboratory conditions. Ten well-trained cyclists completed four consecutive 16.5-min time trials (15-min self-paced effort with 1.5-min maximal end-spurt to determine V̇O2peak) interspersed by 5 min of recovery on a cycle ergometer in each condition. Rectal temperature increased significantly more in HOT (39.4 ± 0.7°C) than COOL (38.6 ± 0.3°C; P < 0.001). Power output was lower throughout HOT compared with COOL (P < 0.001). The decrease in power output from trial 1 to 4 was ∼16% greater in HOT (P < 0.001). Oxygen uptake (V̇o2) was lower throughout HOT than COOL (P < 0.05), except at 5 min and during the end-spurt in trial 1. In HOT, V̇O2peak reached 97, 89, 85, and 85% of predetermined maximal V̇o2, whereas in COOL 97, 94, 93, and 92% were attained. Relative exercise intensity (%V̇O2peak) during trials 1 and 2 was lower in HOT (∼84%) than COOL (∼86%; P < 0.05), decreasing slightly during trials 3 and 4 (∼80 and ∼85%, respectively; P < 0.05). However, heart rate was higher throughout HOT (P = 0.002), and ratings of perceived exertion greater during trials 3 and 4 in HOT (P < 0.05). Consequently, the regulation of self-paced exercise appears to occur in conjunction with the maintenance of %V̇O2peak within a narrow range (80-85% V̇O2peak). This range widens under heat stress, however, when exercise becomes protracted and a disassociation develops between relative exercise intensity, heart rate, and ratings of perceived exertion. Copyright © 2015 the American Physiological Society.
Vandekerckhove, Kristof; Coomans, Ilse; Moerman, Annelies; De Wolf, Daniel; Boone, Jan
2016-12-01
To characterize the oxygenation responses at cerebral and locomotor muscle level to incremental exercise in children and to assess the interrelationship with the pulmonary gas exchange responses. Eighteen children (9 boys, 9 girls) (mean age 10.9 ± 1.0 years) performed incremental cycle ramp exercise to exhaustion. The concentration of cerebral and muscle oxygenated (O 2 Hb) and deoxygenated (HHb) hemoglobin (by means of near-infrared spectroscopy) and pulmonary gas exchange was recorded. Cerebral and muscle O 2 Hb and HHb values were expressed as functions of oxygen uptake (VO 2 ) and breakpoints were detected by means of double linear model analysis. The respiratory compensation point (RCP) was determined. The breakpoints in cerebral and muscle O 2 Hb and HHb were compared and correlated to RCP. The subjects reached peak power output of 105 ± 18 W and VO 2peak of 43.5 ± 7.0 ml min -1 kg -1 . Cerebral O 2 Hb increased to an intensity of 89.4 ± 5.5 %VO 2peak , where a breakpoint occurred at which cerebral O 2 Hb started to decrease. Cerebral HHb increased slightly to 88.1 ± 4.8 %VO 2peak , at which the increase was accelerated. Muscle HHb increased to 90.5 ± 4.8 %VO 2peak where a leveling-off occurred. RCP occurred at 89.3 ± 4.3 %VO 2peak . The breakpoints and RCP did not differ significantly (P = 0.13) and were strongly correlated (r > 0.70, P < 0.05). There were no differences between boys and girls (P = 0.43) and there was no significant correlation with VO 2peak (P > 0.05). It was shown that cerebral and muscle oxygenation responses undergo significant changes as work rate increases and show breakpoints in the ongoing response at high intensity (85-95 %VO 2peak ). These breakpoints are strongly interrelated and associated with changes in pulmonary gas exchange.
Thermally stimulated luminescence studies of undoped, Cu- and Mn-doped CaSO4 compounds
NASA Astrophysics Data System (ADS)
Manam, J.; Das, S.
Thermally stimulated luminescence (TSL) of undoped and doped CaSO4 with activators such as Cu and Mn has been investigated. The polycrystalline samples of undoped and doped CaSO4 are prepared by the melting method. The formation of CaSO4 compound is confirmed by X-ray diffraction and Fourier transform infrared studies. Scanning electron microscopic studies of CaSO4 are also carried out. The TSL glow curves of undoped CaSO4, Cu- and Mn-doped CaSO4 are studied. Comparison of the thermoluminescence (TL) intensity of the most intensive glow peak of Cu-doped CaSO4 compound with that of undoped CaSO4 shows that addition of Cu impurity in CaSO4 compound enhances the TL intensity by about four times. However, the addition of Mn impurity to undoped CaSO4 increases the TL intensity by about three times when compared with that of undoped CaSO4. The TL-dose dependence of all three samples was studied and was observed to be almost linear in the studied range of irradiation time. Among the samples studied, namely undoped CaSO4 and Cu- and Mn-doped CaSO4, Cu-doped CaSO4 is found to be the most sensitive. The trap parameters, namely order of kinetics (b), activation energy (E) and frequency factor (s) associated with the most intensive glow peaks of CaSO4:Mn, CaSO4:Cu and CaSO4 phosphors were determined using the glow curve shape (Chen's) method.
Ramírez-Vélez, Robinson; Tordecilla-Sanders, Alejandra; Téllez-T, Luis Andrés; Camelo-Prieto, Diana; Hernández-Quiñonez, Paula Andrea; Correa-Bautista, Jorge Enrique; Garcia-Hermoso, Antonio; Ramirez-Campillo, Rodrigo; Izquierdo, Mikel
2017-05-30
Metabolic syndrome (MetS) increases the risk of morbidity and mortality from cardiovascular disease, and exercise training is an important factor in the treatment and prevention of the clinical components of MetS. The aim was to compare the effects of high-intensity interval training and steady-state moderate-intensity training on clinical components of MetS in healthy physically inactive adults. Twenty adults were randomly allocated to receive either moderate-intensity continuous training [MCT group; 60-80% heart rate reserve (HRR)] or high-intensity interval training (HIT group; 4 × 4 min at 85-95% peak HRR interspersed with 4 min of active rest at 65% peak HRR). We used the revised International Diabetes Federation criteria for MetS. A MetS Z-score was calculated for each individual and each component of the MetS. In intent-to-treat analyses, the changes in MetS Z-score were 1.546 (1.575) in the MCT group and -1.249 (1.629) in the HIT group (between-groups difference, P = 0.001). The average number of cardiometabolic risk factors changed in the MCT group (-0.133, P = 0.040) but not in the HIT group (0.018, P = 0.294), with no difference between groups (P = 0.277). Among apparently healthy physically inactive adults, HIT and MCT offer similar cardiometabolic protection against single MetS risk factors but differ in their effect on average risk factors per subject. Trial registration ClinicalTrials.gov NCT02738385 registered on March 23, 2016.
Ballesta García, Ismael; Rubio Arias, Jacobo Ángel; Ramos Campo, Domingo Jesús; Martínez González-Moro, Ignacio; Carrasco Poyatos, María
2018-04-09
High-interval intensity training (HIT) has been suggested to improve peak VO 2 in cardiac rehabilitation programs. However, the optimal HIT protocol is unknown. The objective of this study was to identify the most effective doses of HIT to optimize peak VO 2 in coronary artery disease (CAD) and heart failure (HF) patients. A search was conducted in 6 databases (MEDLINE, Web of Science, LILACS, CINAHL, Academic Search Complete, and SportDiscus). Studies using a HIT protocol in CAD or HF patients and measuring peak VO 2 were included. The PEDro Scale and Cochrane Collaboration tools were used. Analyses reported significant improvements in peak VO 2 after HIT in both diseases (P = .000001), with a higher increase in HF patients (P = .03). Nevertheless, in HF patients, there were no improvements when the intensity recovery was ≤ 40% of peak VO 2 (P = .19) and the frequency of training was ≤ 2 d/wk (P = .07). There were significant differences regarding duration in CAD patients, with greater improvements in peak VO 2 when the duration was < 12 weeks (P = .05). In HF, programs lasting < 12 weeks did not significantly improve peak VO 2 (P = .1). The HIT is an effective method for improving peak VO 2 in HF and CAD, with a significantly greater increase in HF patients. The recovery intervals should be active and be between 40% and 60% of peak VO 2 in HF patients. Training frequency should be ≥ 2 d/wk for CAD patients and ≥ 3 d/wk for HF patients. Copyright © 2018 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.
Auffhammer, Maximilian; Baylis, Patrick; Hausman, Catherine H
2017-02-21
It has been suggested that climate change impacts on the electric sector will account for the majority of global economic damages by the end of the current century and beyond [Rose S, et al. (2014) Understanding the Social Cost of Carbon: A Technical Assessment ]. The empirical literature has shown significant increases in climate-driven impacts on overall consumption, yet has not focused on the cost implications of the increased intensity and frequency of extreme events driving peak demand, which is the highest load observed in a period. We use comprehensive, high-frequency data at the level of load balancing authorities to parameterize the relationship between average or peak electricity demand and temperature for a major economy. Using statistical models, we analyze multiyear data from 166 load balancing authorities in the United States. We couple the estimated temperature response functions for total daily consumption and daily peak load with 18 downscaled global climate models (GCMs) to simulate climate change-driven impacts on both outcomes. We show moderate and heterogeneous changes in consumption, with an average increase of 2.8% by end of century. The results of our peak load simulations, however, suggest significant increases in the intensity and frequency of peak events throughout the United States, assuming today's technology and electricity market fundamentals. As the electricity grid is built to endure maximum load, our findings have significant implications for the construction of costly peak generating capacity, suggesting additional peak capacity costs of up to 180 billion dollars by the end of the century under business-as-usual.
The hydrological behaviour of extensive and intensive green roofs in a dry climate.
Razzaghmanesh, M; Beecham, S
2014-11-15
This paper presents the results of a hydrological investigation of four medium scale green roofs that were set up at the University of South Australia. In this study, the potential of green roofs as a source control device was investigated over a 2 year period using four medium size green roof beds comprised of two growth media types and two media depths. During the term of this study, 226 rainfall events were recorded and these were representative of the Adelaide climate. In general, there were no statistically significant differences between the rainfall and runoff parameters for the intensive and extensive beds except for peak attenuation and peak runoff delay, for which higher values were recorded in the intensive beds. Longer dry periods generally resulted in higher retention coefficients and higher retention was also recorded in warmer seasons. The average retention coefficient for intensive systems (89%) was higher than for extensive systems (74%). It was shown that rainfall depth, intensity, duration and also average dry weather period between events can change the retention performance and runoff volume of the green roofs. Comparison of green and simulated conventional roofs indicated that the former were able to mitigate the peak of runoff and could delay the start of runoff. These characteristics are important for most source control measures. The recorded rainfall and runoff data displayed a non-linear relationship. Also, the results indicated that continuous time series modelling would be a more appropriate technique than using peak rainfall intensity methods for green roof design and simulation. Copyright © 2014 Elsevier B.V. All rights reserved.
Stöggl, Thomas L; Björklund, Glenn
2017-01-01
The purpose of the current study was to explore if training regimes utilizing diverse training intensity distributions result in different responses on neuromuscular status, anaerobic capacity/power and acute heart rate recovery (HRR) in well-trained endurance athletes. Methods: Thirty-six male ( n = 33) and female ( n = 3) runners, cyclists, triathletes and cross-country skiers [peak oxygen uptake: (VO 2peak ): 61.9 ± 8.0 mL·kg -1 ·min -1 ] were randomly assigned to one of three groups (blocked high intensity interval training HIIT; polarized training POL; high volume low intensity oriented control group CG/HVLIT applying no HIIT). A maximal anaerobic running/cycling test (MART/MACT) was performed prior to and following a 9-week training period. Results: Only the HIIT group achieved improvements in peak power/velocity (+6.4%, P < 0.001) and peak lactate ( P = 0.001) during the MART/MACT, while, unexpectedly, in none of the groups the performance at the established lactate concentrations (4, 6, 10 mmol·L -1 ) was changed ( P > 0.05). Acute HRR was improved in HIIT (11.2%, P = 0.002) and POL (7.9%, P = 0.023) with no change in the HVLIT oriented control group. Conclusion: Only a training regime that includes a significant amount of HIIT improves the neuromuscular status, anaerobic power and the acute HRR in well-trained endurance athletes. A training regime that followed more a low and moderate intensity oriented model (CG/HVLIT) had no effect on any performance or HRR outcomes.
Stöggl, Thomas L.; Björklund, Glenn
2017-01-01
The purpose of the current study was to explore if training regimes utilizing diverse training intensity distributions result in different responses on neuromuscular status, anaerobic capacity/power and acute heart rate recovery (HRR) in well-trained endurance athletes. Methods: Thirty-six male (n = 33) and female (n = 3) runners, cyclists, triathletes and cross-country skiers [peak oxygen uptake: (VO2peak): 61.9 ± 8.0 mL·kg−1·min−1] were randomly assigned to one of three groups (blocked high intensity interval training HIIT; polarized training POL; high volume low intensity oriented control group CG/HVLIT applying no HIIT). A maximal anaerobic running/cycling test (MART/MACT) was performed prior to and following a 9-week training period. Results: Only the HIIT group achieved improvements in peak power/velocity (+6.4%, P < 0.001) and peak lactate (P = 0.001) during the MART/MACT, while, unexpectedly, in none of the groups the performance at the established lactate concentrations (4, 6, 10 mmol·L−1) was changed (P > 0.05). Acute HRR was improved in HIIT (11.2%, P = 0.002) and POL (7.9%, P = 0.023) with no change in the HVLIT oriented control group. Conclusion: Only a training regime that includes a significant amount of HIIT improves the neuromuscular status, anaerobic power and the acute HRR in well-trained endurance athletes. A training regime that followed more a low and moderate intensity oriented model (CG/HVLIT) had no effect on any performance or HRR outcomes. PMID:28824457
The Effectiveness of Progressive Aerobic Interval Training in Cardiac Rehabilitation.
Lee, Leanna S; Tsai, Ming-Chang; Oh, Paul I; Brooks, Dina
2018-05-01
Aerobic interval training (AIT) has recently emerged as a more effective strategy than moderate-intensity continuous exercise (MICE) for improving peak oxygen consumption (V˙O2peak) in coronary artery disease (CAD) patients. The primary purpose of this retrospective study was to describe the change in V˙O2peak, and cardiovascular (CV) risk profile characteristics (secondary outcomes) after progressive AIT practiced in the largest, outpatient cardiac rehabilitation (CR) program in North America compared with usual care CR involving MICE. Electronic database records were retrieved from consecutively enrolled patients with CAD who attended the Toronto Rehabilitation Institute, between January 1, 2005, and December 31, 2015. Patients were then separated into two, age and sex propensity score-matched groups: 772 patients were prescribed 26 wk of MICE (60%-80% of V˙O2peak, five times per week) as per usual care CR (56.0 ± 9.2 yr; 12% female/88% male; V˙O2peak: 20.8 ± 5.9 mL·kg·min), and 772 patients were prescribed 26 wk of progressive walk/jog intervals (15 min·mile walking pace, 12 min·mile jogging pace, five times per week) (55.9 ± 9.3 yr; 12% female/88% male; V˙O2peak: 24.8 ± 5.7 mL·kg ·min). Treatment effect analysis of AIT on V˙O2peak and CV risk profile characteristics was performed using multiple regression with baseline values as covariates. Treatment effect analysis revealed a 3.84-mL·kg·min superior improvement in V˙O2peak in the AIT group compared to usual care MICE group (P < 0.001). Furthermore, AIT significantly improved BMI, triglycerides, hip and abdominal girth, and depression score compared with MICE (P < 0.023 for all). Progressive AIT performed in a standard, outpatient CR program appears to be superior to usual care MICE for improving V˙O2peak, CV risk profile characteristics, and depression score in stable CAD patients. These findings may have important implications for exercise training guidelines in the rehabilitation setting, and in future studies.
NASA Astrophysics Data System (ADS)
He, H.-Q.; Zhou, G.; Wan, W.
2017-06-01
A functional form {I}\\max (R)={{kR}}-α , where R is the radial distance of a spacecraft, was usually used to model the radial dependence of peak intensities {I}\\max (R) of solar energetic particles (SEPs). In this work, the five-dimensional Fokker-Planck transport equation incorporating perpendicular diffusion is numerically solved to investigate the radial dependence of SEP peak intensities. We consider two different scenarios for the distribution of a spacecraft fleet: (1) along the radial direction line and (2) along the Parker magnetic field line. We find that the index α in the above expression varies in a wide range, primarily depending on the properties (e.g., location and coverage) of SEP sources and on the longitudinal and latitudinal separations between the sources and the magnetic foot points of the observers. Particularly, whether the magnetic foot point of the observer is located inside or outside the SEP source is a crucial factor determining the values of index α. A two-phase phenomenon is found in the radial dependence of peak intensities. The “position” of the break point (transition point/critical point) is determined by the magnetic connection status of the observers. This finding suggests that a very careful examination of the magnetic connection between the SEP source and each spacecraft should be taken in the observational studies. We obtain a lower limit of {R}-1.7+/- 0.1 for empirically modeling the radial dependence of SEP peak intensities. Our findings in this work can be used to explain the majority of the previous multispacecraft survey results, and especially to reconcile the different or conflicting empirical values of the index α in the literature.
NASA Astrophysics Data System (ADS)
Santiago, Brandon G.; Harris, Rachel A.; Isenberg, Samantha L.; Ridgeway, Mark E.; Pilo, Alice L.; Kaplan, Desmond A.; Glish, Gary L.
2015-07-01
Differential ion mobility spectrometry (DIMS) separates ions based on differences in their mobilities in low and high electric fields. When coupled to mass spectrometric analyses, DIMS has the ability to improve signal-to-background by eliminating isobaric and isomeric compounds for analytes in complex mixtures. DIMS separation power, often measured by resolution and peak capacity, can be improved through increasing the fraction of helium in the nitrogen carrier gas. However, because the mobility of ions is higher in helium, a greater number of ions collide with the DIMS electrodes or housing, yielding losses in signal intensity. To take advantage of the benefits of helium addition on DIMS separations and reduce ion losses, linked scans were developed. In a linked scan the helium content of the carrier gas is reduced as the compensation field is increased. Linked scans were compared with conventional compensation field scans with constant helium content for the protein ubiquitin and a tryptic digest of bovine serum albumin (BSA). Linked scans yield better separation of ubiquitin charge states and enhanced peak capacities for the analysis of BSA compared with compensation field scans with constant helium carrier gas percentages. Linked scans also offer improved signal intensity retention in comparison to compensation field scans with constant helium percentages in the carrier gas.
Gugliotti, C; Moriya, K; Tatumi, S; Mittani, J
2018-05-01
In the present work, MgO ceramic samples with different terbium concentrations were produced and the Thermoluminescence (TL) and Optically Stimulated Luminescence (OSL) properties analyzed and discussed, aiming the use in radiation dosimetry. The samples were produced using MgO, Mg(NO 3 ) 2 ·6H 2 O, Al 2 O 3 , SiO 2 and Tb(NO 3 ) 3 ·6H 2 O precursors in stoichiometric concentrations with five different terbium concentrations between 0.1 and 0.5 mol% and after, heat-treated at high temperature ~1500 °C. X-ray diffraction measurements on samples showed the formation of MgO as principal phase, and others in low concentration due to MgAl 2 O 4 , Mg 2 SiO 4 and Tb 4 O 7 phases. The TL glow curve of samples showed an intense and well-defined peak having the maximum at ~210 °C and other less intense at ~350 °C. The sample with 0.1 mol% of terbium concentration presented highest luminescence peak when compared to the other samples. The relationship between 210 °C TL peak intensity and dose was linear to doses between 1 and 20 Gy and the minimum detectable dose obtained by interpolation taking into account three times the standard deviation of the zero dose reading, was ~40 μGy. A fading of ~20% during the first 5 hours after irradiation of 210 °C peak was observed. TL emission spectra showed strong emission lines due to Tb 3+ ion. The OSL signal presented a linear behavior to doses between 1 and 10 Gy using 532 nm wavelength stimulation. Copyright © 2018 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Becker, J.; Pabst, H.; Mnyonga, J.; Kuzyakov, Y.
2015-10-01
Litterfall is one of the major pathways connecting above- and below-ground processes. The effects of climate and land-use change on carbon (C) and nutrient inputs by litterfall are poorly known. We quantified and analyzed annual patterns of C and nutrient deposition via litterfall in natural forests and agroforestry systems along the unique elevation gradient of Mt. Kilimanjaro. Tree litter in three natural (lower montane, Ocotea and Podocarpus forests), two sustainably used (homegardens) and one intensively managed (shaded coffee plantation) ecosystems was collected on a biweekly basis from May 2012 to July 2013. Leaves, branches and remaining residues were separated and analyzed for C and nutrient contents. The annual pattern of litterfall was closely related to rainfall seasonality, exhibiting a large peak towards the end of the dry season (August-October). This peak decreased at higher elevations with decreasing rainfall seasonality. Macronutrients (N, P, K) in leaf litter increased at mid elevation (2100 m a.s.l.) and with land-use intensity. Carbon content and micronutrients (Al, Fe, Mn, Na) however, were unaffected or decreased with land-use intensity. While leaf litterfall decreased with elevation, total annual input was independent of climate. Compared to natural forests, the nutrient cycles in agroforestry ecosystems were accelerated by fertilization and the associated changes in dominant tree species.
Turbulence Enhancement by Fractal Square Grids: Effects of the Number of Fractal Scales
NASA Astrophysics Data System (ADS)
Omilion, Alexis; Ibrahim, Mounir; Zhang, Wei
2017-11-01
Fractal square grids offer a unique solution for passive flow control as they can produce wakes with a distinct turbulence intensity peak and a prolonged turbulence decay region at the expense of only minimal pressure drop. While previous studies have solidified this characteristic of fractal square grids, how the number of scales (or fractal iterations N) affect turbulence production and decay of the induced wake is still not well understood. The focus of this research is to determine the relationship between the fractal iteration N and the turbulence produced in the wake flow using well-controlled water-tunnel experiments. Particle Image Velocimetry (PIV) is used to measure the instantaneous velocity fields downstream of four different fractal grids with increasing number of scales (N = 1, 2, 3, and 4) and a conventional single-scale grid. By comparing the turbulent scales and statistics of the wake, we are able to determine how each iteration affects the peak turbulence intensity and the production/decay of turbulence from the grid. In light of the ability of these fractal grids to increase turbulence intensity with low pressure drop, this work can potentially benefit a wide variety of applications where energy efficient mixing or convective heat transfer is a key process.
NASA Astrophysics Data System (ADS)
Leske, R. A.; Cummings, A. C.; Mewaldt, R. A.; Cohen, C.; Stone, E. C.; Wiedenbeck, M. E.
2017-12-01
Anomalous cosmic ray (ACR) intensities at 1 AU generally track galactic cosmic ray (GCR) intensities, but with differences between solar polarity cycles: at high rigidities, GCRs reach higher peak intensities during A<0 cycles, while ACRs have been higher at A>0 solar minima. At present, during the approach to an A>0 solar minimum, ACR oxygen above 8 MeV/nucleon as measured by the Advanced Composition Explorer (ACE) has already reached the peak intensities seen during the 2009 A<0 solar minimum, but is still 40% below the levels seen in 1997 during the last A>0 minimum. The GCR iron intensity at 300 MeV/nucleon, on the other hand, is presently comparable to that in 1997 but remains 10% below its record-setting 2009 value. Drift effects play an important role in the modulation of both ACRs and GCRs. Positively charged ions drift inward along the heliospheric current sheet (HCS) during A<0 cycles and their intensities are thus sensitive to the HCS tilt angle, which remained high for much of the last solar cycle. We have previously shown that both ACR and GCR intensities were significantly higher for a given HCS tilt angle during the 2000-2012 A<0 cycle than they were during the prior (1980-1990) A<0 cycle, and this trend appears to be continuing into the new A>0 cycle. But while GCR intensities in 2009 reached the highest levels recorded during the last 50 years, ACR intensities were only similar to those in the 1980s A<0 minimum. Factors such as a weaker interplanetary magnetic field, perhaps with a reduction in the ACR source strength or greater sensitivity of ACRs than GCRs to the HCS tilt angle, may account for the difference in their modulation behavior.We present 20 years of ACR and GCR intensity data acquired by ACE throughout two solar cycles, with emphasis on recent observations, and discuss possible reasons for the differences in the relative behavior of ACRs and GCRs in the different solar cycles.
Isometric strength training lowers the O2 cost of cycling during moderate-intensity exercise.
Zoladz, Jerzy A; Szkutnik, Zbigniew; Majerczak, Joanna; Grandys, Marcin; Duda, Krzysztof; Grassi, Bruno
2012-12-01
The effect of maximal voluntary isometric strength training of knee extensor muscles on pulmonary V'O(2) on-kinetics, the O(2) cost of cycling and peak oxygen uptake (V'O(2peak)) in humans was studied. Seven healthy males (mean ± SD, age 22.3 ± 2.0 years, body weight 75.0 ± 9.2 kg, V'O(2peak) 49.5 ± 3.8 ml kg(-1) min(-1)) performed maximal isometric strength training lasting 7 weeks (4 sessions per week). Force during maximal voluntary contraction (MVC) increased by 15 % (P < 0.001) after 1 week of training, and by 19 % (P < 0.001) after 7 weeks of training. This increase in MVC was accompanied by no significant changes in the time constant of the V'O(2) on-kinetics during 6 min of moderate and heavy cycling intensities. Strength training resulted in a significant decrease (by ~7 %; P < 0.02) in the amplitude of the fundamental component of the V'O(2) on-kinetics, and therefore in a lower O(2) cost of cycling during moderate cycling intensity. The amplitude of the slow component of V'O(2) on-kinetics during heavy cycling intensity did not change with training. Training had no effect on the V'O(2peak), whereas the maximal power output reached at V'O(2peak) was slightly but significantly increased (P < 0.05). Isometric strength training rapidly (i.e., after 1 week) decreases the O(2) cost of cycling during moderate-intensity exercise, whereas it does not affect the amplitude of the slow component of the V'O(2) on-kinetics during heavy-intensity exercise. Isometric strength training can have beneficial effects on performance during endurance events.
NASA Astrophysics Data System (ADS)
Sharma, Trupti; Singhal, R.; Vishnoi, R.; Biswas, S. K.
2017-05-01
The structural and optical properties of bulk heterojunction (BHJ) organic solar cell devices have been studied before and after heat treatment. The BHJ structure is fabricated by making the blend of Poly [3-hexylthiophene] (P3HT) and Phenyl C61 butyric acid methyl ester (PCBM) for active layer. After the heat treatment at 140 °C temperature, the device is characterized by X-ray diffraction (XRD) measurement, Raman spectroscopy and UV-visible absorption spectroscopy. The reduced intensity of XRD peak corresponding to (100) plane and decreased crystallite size was observed after annealing. The Raman peak intensity corresponding to C=C stretching mode and optical absorption peak intensity is also found to be reduced after the heat treatment to the device. The diminished intensitiesafter annealing may be due to diffusion of Al into active layer.
Quantification of Protein Biomarker Using SERS Nano-Stress Sensing with Peak Intensity Ratiometry
NASA Astrophysics Data System (ADS)
Goh, Douglas; Kong, Kien Voon; Jayakumar, Perumal; Gong, Tianxun; Dinish, U. S.; Olivo, Malini
We report a surface enhanced Raman spectroscopy (SERS) ratiometry method based on peak intensity coupled in a nano-stress sensing platform to detect and quantify biological molecules. Herein, we employed an antibody-conjugated p-aminothiophenol (ATP) functionalized on a bimetallic-film-over-nanosphere (BMFON) substrate as a sensitive SERS platform to detect human haptoglobin (Hp) protein, which is an acute phase protein and a biomarker for various cancers. Correlation between change in the ATP spectral characteristics and concentration of Hp protein was established by examining the peak intensity ratio at 1572cm-1 and 1592cm-1 that reflects the degree of stress experienced by the aromatic ring of ATP during Hp protein-antibody interaction. Development of this platform shows the potential in developing a low-cost and sensitive SERS sensor for the pre-screening of various biomarkers.
Verma, Ajay; Baishya, Bikash
2016-05-01
"Pure shift" NMR spectra display singlet peak per chemical site. Thus, high resolution is offered at the cost of valuable J-coupling information. In the present work, real-time BIRD (BIlinear Rotation Decoupling) is applied to the absorptive-mode 2D J-spectroscopy to provide pure shift spectrum in the direct dimension and J-coupling information in the indirect dimension. Quite often in metabolomics, proton NMR spectra from complex bio-fluids display tremendous signal overlap. Although conventional J-spectroscopy in principle overcomes this problem by separating the multiplet information from chemical shift information, however, only magnitude mode of the experiment is practical, sacrificing much of the potential high resolution that could be achieved. Few J-spectroscopy methods have been reported so far that produce high-resolution pure shift spectrum along with J-coupling information for crowded spectral regions. In the present work, high-quality J-resolved spectrum from important metabolomic mixture such as tissue extract from rat cortex is demonstrated. Many low-intensity metabolite peaks which are obscured by the broad dispersive tails from high-intensity metabolite peaks in regular magnitude mode J-spectrum can be clearly identified in real-time BIRD J-resolved spectrum. The general practice of removing such spectral overlap is tedious and time-consuming as it involves repeated sample preparation to change the pH of the tissue extract sample and subsequent spectra recording. Copyright © 2016 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Verma, Ajay; Baishya, Bikash
2016-05-01
;Pure shift; NMR spectra display singlet peak per chemical site. Thus, high resolution is offered at the cost of valuable J-coupling information. In the present work, real-time BIRD (BIlinear Rotation Decoupling) is applied to the absorptive-mode 2D J-spectroscopy to provide pure shift spectrum in the direct dimension and J-coupling information in the indirect dimension. Quite often in metabolomics, proton NMR spectra from complex bio-fluids display tremendous signal overlap. Although conventional J-spectroscopy in principle overcomes this problem by separating the multiplet information from chemical shift information, however, only magnitude mode of the experiment is practical, sacrificing much of the potential high resolution that could be achieved. Few J-spectroscopy methods have been reported so far that produce high-resolution pure shift spectrum along with J-coupling information for crowded spectral regions. In the present work, high-quality J-resolved spectrum from important metabolomic mixture such as tissue extract from rat cortex is demonstrated. Many low-intensity metabolite peaks which are obscured by the broad dispersive tails from high-intensity metabolite peaks in regular magnitude mode J-spectrum can be clearly identified in real-time BIRD J-resolved spectrum. The general practice of removing such spectral overlap is tedious and time-consuming as it involves repeated sample preparation to change the pH of the tissue extract sample and subsequent spectra recording.
ERIC Educational Resources Information Center
Durham, Chaney R.; Chase, Jeffery M.; Nivens, Delana A.; Baird, William H.; Padgett, Clifford W.
2011-01-01
X-ray fluorescence (XRF) data from an energy-dispersive XRF instrument were used to investigate the chlorine K[alpha] and K[beta] peaks in several group 1 salts. The ratio of the peak intensity is sensitive to the local chemical environment of the chlorine atoms studied in this experiment and it shows a periodic trend for these salts. (Contains 1…
A Kp-based model of auroral boundaries
NASA Astrophysics Data System (ADS)
Carbary, James F.
2005-10-01
The auroral oval can serve as both a representation and a prediction of space weather on a global scale, so a competent model of the oval as a function of a geomagnetic index could conveniently appraise space weather itself. A simple model of the auroral boundaries is constructed by binning several months of images from the Polar Ultraviolet Imager by Kp index. The pixel intensities are first averaged into magnetic latitude-magnetic local time (MLT-MLAT) and local time bins, and intensity profiles are then derived for each Kp level at 1 hour intervals of MLT. After background correction, the boundary latitudes of each profile are determined at a threshold of 4 photons cm-2 s1. The peak locations and peak intensities are also found. The boundary and peak locations vary linearly with Kp index, and the coefficients of the linear fits are tabulated for each MLT. As a general rule of thumb, the UV intensity peak shifts 1° in magnetic latitude for each increment in Kp. The fits are surprisingly good for Kp < 6 but begin to deteriorate at high Kp because of auroral boundary irregularities and poor statistics. The statistical model allows calculation of the auroral boundaries at most MLTs as a function of Kp and can serve as an approximation to the shape and extent of the statistical oval.
Rock Burst Monitoring by Integrated Microseismic and Electromagnetic Radiation Methods
NASA Astrophysics Data System (ADS)
Li, Xuelong; Wang, Enyuan; Li, Zhonghui; Liu, Zhentang; Song, Dazhao; Qiu, Liming
2016-11-01
For this study, microseismic (MS) and electromagnetic radiation (EMR) monitoring systems were installed in a coal mine to monitor rock bursts. The MS system monitors coal or rock mass ruptures in the whole mine, whereas the EMR equipment monitors the coal or rock stress in a small area. By analysing the MS energy, number of MS events, and EMR intensity with respect to rock bursts, it has been shown that the energy and number of MS events present a "quiet period" 1-3 days before the rock burst. The data also show that the EMR intensity reaches a peak before the rock burst and this EMR intensity peak generally corresponds to the MS "quiet period". There is a positive correlation between stress and EMR intensity. Buckling failure of coal or rock depends on the rheological properties and occurs after the peak stress in the high-stress concentration areas in deep mines. The MS "quiet period" before the rock burst is caused by the heterogeneity of the coal and rock structures, the transfer of high stress into internal areas, locked patches, and self-organized criticality near the stress peak. This study increases our understanding of coal and rock instability in deep mines. Combining MS and EMR to monitor rock burst could improve prediction accuracy.
NASA Astrophysics Data System (ADS)
Jordán, Antonio; Zavala, Lorena M.; Gordillo-Rivero, Ángel J.; Miriam, Miriam; Keesstra, Saskia; Cerdà, Artemi
2017-04-01
We know that the impact of fire on soil water repellency varies largely with the availability of water and physical and chemical soil properties, as well as the intensity of pre-existing hydrophobicity. However, there are few studies that relate the intensity of post-fire soil hydrophobicity and its persistence to the intensity and duration of thermal peaks occurring during fire. Fundamentally, this is due to the difficulty of quantifying these factors in situ, so that experimental fires are an extremely useful tool. The objective of this work was to study the impact of the intensity and duration of the thermal peaks observed during an experimental fire in the hydrophobicity of previously wet or slightly hydrophobic soils and the consequences of these changes on infiltration, runoff and soil loss (through rainfall simulation) in the immediate (30 days) and medium-term (1 year) post-fire period. In general, soil water repellency increased in all cases, although high temperatures and residence times of moderate thermal peaks caused the greatest impact. Although infiltration rates determined by mini-disk infiltrometer with water generally declined, no significant changes were observed in the same measurement with ethanol (which negates the effect of hydrophobicity).
Hu, Meng; Krauss, Martin; Brack, Werner; Schulze, Tobias
2016-11-01
Liquid chromatography-high resolution mass spectrometry (LC-HRMS) is a well-established technique for nontarget screening of contaminants in complex environmental samples. Automatic peak detection is essential, but its performance has only rarely been assessed and optimized so far. With the aim to fill this gap, we used pristine water extracts spiked with 78 contaminants as a test case to evaluate and optimize chromatogram and spectral data processing. To assess whether data acquisition strategies have a significant impact on peak detection, three values of MS cycle time (CT) of an LTQ Orbitrap instrument were tested. Furthermore, the key parameter settings of the data processing software MZmine 2 were optimized to detect the maximum number of target peaks from the samples by the design of experiments (DoE) approach and compared to a manual evaluation. The results indicate that short CT significantly improves the quality of automatic peak detection, which means that full scan acquisition without additional MS 2 experiments is suggested for nontarget screening. MZmine 2 detected 75-100 % of the peaks compared to manual peak detection at an intensity level of 10 5 in a validation dataset on both spiked and real water samples under optimal parameter settings. Finally, we provide an optimization workflow of MZmine 2 for LC-HRMS data processing that is applicable for environmental samples for nontarget screening. The results also show that the DoE approach is useful and effort-saving for optimizing data processing parameters. Graphical Abstract ᅟ.
Neunhäuserer, Daniel; Steidle-Kloc, Eva; Weiss, Gertraud; Kaiser, Bernhard; Niederseer, David; Hartl, Sylvia; Tschentscher, Marcus; Egger, Andreas; Schönfelder, Martin; Lamprecht, Bernd; Studnicka, Michael; Niebauer, Josef
2016-11-01
Physical exercise training is an evidence-based treatment in chronic obstructive pulmonary disease, and patients' peak work rate is associated with reduced chronic obstructive pulmonary disease mortality. We assessed whether supplemental oxygen during exercise training in nonhypoxemic patients with chronic obstructive pulmonary disease might lead to superior training outcomes, including improved peak work rate. This was a randomized, double-blind, controlled, crossover trial. Twenty-nine patients with chronic obstructive pulmonary disease (aged 63.5 ± 5.9 years; forced expiratory volume in 1 second percent predicted, 46.4 ± 8.6) completed 2 consecutive 6-week periods of endurance and strength training with progressive intensity, which was performed 3 times per week with supplemental oxygen or compressed medical air (flow via nasal cannula: 10 L/min). Each session of electrocardiography-controlled interval cycling lasted 31 minutes and consisted of a warm-up, 7 cycles of 1-minute intervals at 70% to 80% of peak work rate alternating with 2 minutes of active recovery, and final cooldown. Thereafter, patients completed 8 strength-training exercises of 1 set each with 8 to 15 repetitions to failure. Change in peak work rate was the primary study end point. The increase in peak work rate was more than twice as high when patients exercised with supplemental oxygen compared with medical air (0.16 ± 0.02 W/kg vs 0.07 ± 0.02 W/kg; P < .001), which was consistent with all other secondary study end points related to exercise capacity. The impact of oxygen on peak work rate was 39.1% of the overall training effect, whereas it had no influence on strength gain (P > .1 for all exercises). We report that supplemental oxygen in nonhypoxemic chronic obstructive pulmonary disease doubled the effect of endurance training but had no effect on strength gain. Copyright © 2016 Elsevier Inc. All rights reserved.
Erny, Guillaume L; Simó, Carolina; Cifuentes, Alejandro; Esteves, Valdemar I
2014-02-21
In separation techniques hyphenated to mass spectrometry (MS) the bulk from the separation step is continuously flowing into the mass spectrometer where the compounds, arriving at each separation time, are ionized and further separated based on their m/z ratio. An MS detector is recognized as being a universal detector, although it can also be a very selective instrument. In spite of these advantages, classical two dimensional representations from these hyphenated systems, such as those based on the base peak of electropherogram/chromatogram or on the total ion of electropherogram/chromatogram, usually hide a large number of features that if correctly assessed will show the presence of co-migrating species and/or the low abundant ones. The uses of peak picking algorithms to detect and measure as many peaks as possible from a dataset allow extracting much more information. However, a single migrating compound usually produces a multiplicity of ions, making difficult to differentiate peaks generated by the same compound from other peaks due e.g., to closely co-migrating/eluting species. In this work, a new representation is proposed and its usefulness demonstrated with experimental data from capillary electrophoresis-hyphenated to a time of flight mass spectrometer via an electrospray interface. This representation, called centergram, is obtained after using a peak picking methodology that detects electrophoretic peaks of single ions and measure their positions. The centergram is the histogram (i.e. the count of the number of observations that fall into each one of the intervals, known as bins, as determined by the user) of the measured positions. The intensity of the bars in this histogram will indicate the amount of peaks in the whole dataset whose centers are within each interval. As a compound that has been separated and has entered the MS instrument will produce multiple images at the same position along the m/z dimension, the centergram will exhibit a series of intense bars around the migration time. Those bars will allow defining a centergram peak whose area will be proportional to the number of different types of ions that have been generated in the ionization chamber, the position will be equal to the migration/retention time of the parent compounds and the width will depend on the precision in the measurement of the peak positions. The efficiency of this peak is determined to be up to thirty times higher than the equivalent peak in the classical base peak electropherogram allowing detecting easily co-migrating peaks or the presence of compounds at very low abundance. The number of peaks detected by using this new tool called centergram was increased by more than a factor of 3 compared to the standard representations. Copyright © 2014 Elsevier B.V. All rights reserved.
Andreev, Victor P; Rejtar, Tomas; Chen, Hsuan-Shen; Moskovets, Eugene V; Ivanov, Alexander R; Karger, Barry L
2003-11-15
A new denoising and peak picking algorithm (MEND, matched filtration with experimental noise determination) for analysis of LC-MS data is described. The algorithm minimizes both random and chemical noise in order to determine MS peaks corresponding to sample components. Noise characteristics in the data set are experimentally determined and used for efficient denoising. MEND is shown to enable low-intensity peaks to be detected, thus providing additional useful information for sample analysis. The process of denoising, performed in the chromatographic time domain, does not distort peak shapes in the m/z domain, allowing accurate determination of MS peak centroids, including low-intensity peaks. MEND has been applied to denoising of LC-MALDI-TOF-MS and LC-ESI-TOF-MS data for tryptic digests of protein mixtures. MEND is shown to suppress chemical and random noise and baseline fluctuations, as well as filter out false peaks originating from the matrix (MALDI) or mobile phase (ESI). In addition, MEND is shown to be effective for protein expression analysis by allowing selection of a large number of differentially expressed ICAT pairs, due to increased signal-to-noise ratio and mass accuracy.
Burseg, Kerstin Martha Mensien; Brattinga, Celine; de Kok, Petrus Maria Theresia; Bult, Johannes Hendrikus Franciscus
2010-06-16
When aqueous NaCl solutions are tasted at continuously alternating concentrations, overall saltiness ratings exceed those observed for solutions with the same averaged, but non-alternating concentrations. In the present study, this effect is replicated for alternating aqueous sucrose solutions. We tested the hypothesis that enhancement depends on the conscious perception of intensity contrasts. High sucrose pulses were continuously alternated with low sucrose intervals at pulsation periods between 1.5s and 20s. Tastant pulsation enhanced sweetness intensity and this enhancement varied between 8 and 14%, peaking for periods from 4.5s to 6s (Study 1). This range coincided with the average pulsation period at which perceived taste pulses blended into a continuous stimulus, i.e. the taste fusion period (TFP). When comparing intensity ratings of sucrose solutions at individualized pulse periods of 0.5, 1.0 and 2.0 times TFP to ratings for continuous sucrose solutions of the same net concentration, pulsatile stimuli were perceived as significantly sweeter (p<0.01; Study 2). However, sweetness intensity enhancement was the same for all pulsation periods. It was shown that sweet taste enhancement peaks at pulsation periods ranging from 0.5 to 2.0 TFP and that the level of conscious pulsation perception does not affect taste enhancement. The results suggest the introduction of enhancement effects at pre-conscious stages of gustatory processing. Further mechanisms that may account for such pre-conscious effects are discussed. (c) 2010 Elsevier Inc. All rights reserved.
Byun, Kyeongho; Hyodo, Kazuki; Suwabe, Kazuya; Kujach, Sylwester; Kato, Morimasa; Soya, Hideaki
2014-01-01
[Purpose] Functional near-infrared spectroscopy (fNIRS) provides functional imaging of cortical activations by measuring regional oxy- and deoxy-hemoglobin (Hb) changes in the forehead during a cognitive task. There are, however, potential problems regarding NIRS signal contamination by non-cortical hemodynamic (NCH) variables such as skin blood flow, middle cerebral artery blood flow, and heart rate (HR), which are further complicated during acute exercise. It is thus necessary to determine the appropriate post-exercise timing that allows for valid NIRS assessment during a task without any increase in NCH variables. Here, we monitored post-exercise changes in NCH parameters with different intensities of exercise. [Methods] Fourteen healthy young participants cycled 30, 50 and 70% of their peak oxygen uptake (Vo2peak) for 10 min per intensity, each on different days. Changes in skin blood flow velocity (SBFv), middle cerebral artery mean blood velocity (MCA Vmean) and HR were monitored before, during, and after the exercise. [Results] Post-exercise levels of both SBFv and HR in contrast to MCA Vmean remained high compared to basal levels and the times taken to return to baseline levels for both parameters were delayed (2-8 min after exercise), depending upon exercise intensity. [Conclusion] These results indicate that the delayed clearance of NCH variables of up to 8 min into the post-exercise phase may contaminate NIRS measurements, and could be a limitation of NIRS-based neuroimaging studies. PMID:25671198
Ferreira-Junior, J B; Bottaro, M; Vieira, C A; Soares, S R S; Vieira, A; Cleto, V A; Cadore, E L; Coelho, D B; Simoes, H G; Brown, L E
2014-12-01
The aim of this study was to evaluate the effects of a single partial-body cryotherapy bout between training sessions on strength recovery. 12 young men (23.9±5.9 years) were randomly exposed to 2 different conditions separated by 7 days: 1) Partial-body cryotherapy (subjects were exposed to 3 min of partial-body cryotherapy at - 110 °C between 2 high-intensity training sessions); 2) Control (subjects were not exposed to partial-body cryotherapy between 2 high-intensity training sessions). Subjects were exposed to partial-body cryotherapy after the first training session. The 2 knee extension high-intensity training sessions were separated by a 40-min rest interval. Knee extension training consisted of 6 sets of 10 repetitions at 60°.s(-1) for concentric actions and 6 sets of 10 at 180.s(-1) for eccentric actions. The decrease in eccentric peak torque and total work was significantly (p<0.05) less after partial-body cryotherapy (5.6 and 2%, respectively) when compared to control (16 and 11.6%, respectively). However, the decrease in concentric peak torque and total work was not different (p>0.05) between partial-body cryotherapy (9.4 and 6.5%, respectively) and control (7.5 and 5.2%, respectively). These results indicate that the use of partial-body cryotherapy between-training sessions can enhance eccentric muscle performance recovery. © Georg Thieme Verlag KG Stuttgart · New York.
Chromospheric evaporation flows and density changes deduced from Hinode/EIS during an M1.6 flare
NASA Astrophysics Data System (ADS)
Gömöry, P.; Veronig, A. M.; Su, Y.; Temmer, M.; Thalmann, J. K.
2016-04-01
Aims: We study the response of the solar atmosphere during a GOES M1.6 flare using spectroscopic and imaging observations. In particular, we examine the evolution of the mass flows and electron density together with the energy input derived from hard X-ray (HXR) in the context of chromospheric evaporation. Methods: We analyzed high-cadence sit-and-stare observations acquired with the Hinode/EIS spectrometer in the Fe xiii 202.044 Å (log T = 6.2) and Fe xvi 262.980 Å (log T = 6.4) spectral lines to derive temporal variations of the line intensity, Doppler shifts, and electron density during the flare. We combined these data with HXR measurements acquired with RHESSI to derive the energy input to the lower atmosphere by flare-accelerated electrons. Results: During the flare impulsive phase, we observe no significant flows in the cooler Fe xiii line but strong upflows, up to 80-150 km s-1, in the hotter Fe xvi line. The largest Doppler shifts observed in the Fe xvi line were co-temporal with the sharp intensity peak. The electron density obtained from a Fe xiii line pair ratio exhibited fast increase (within two minutes) from the pre-flare level of 5.01 × 109 cm-3 to 3.16 × 1010 cm-3 during the flare peak. The nonthermal energy flux density deposited from the coronal acceleration site to the lower atmospheric layers during the flare peak was found to be 1.34 × 1010 erg s-1 cm-2 for a low-energy cut-off that was estimated to be 16 keV. During the decline flare phase, we found a secondary intensity and density peak of lower amplitude that was preceded by upflows of ~15 km s-1 that were detected in both lines. The flare was also accompanied by a filament eruption that was partly captured by the EIS observations. We derived Doppler velocities of 250-300 km s-1 for the upflowing filament material. Conclusions: The spectroscopic results for the flare peak are consistent with the scenario of explosive chromospheric evaporation, although a comparatively low value of the nonthermal energy flux density was determined for this phase of the flare. This outcome is discussed in the context of recent hydrodynamic simulations. It provides observational evidence that the response of the atmospheric plasma strongly depends on the properties of the electron beams responsible for the heating, in particular the steepness of the energy distribution. The secondary peak of line intensity and electron density detected during the decline phase is interpreted as a signature of flare loops being filled by expanding hot material that is due to chromospheric evaporation. A movie is available at http://www.aanda.org
High-intensity interval training has positive effects on performance in ice hockey players.
Naimo, M A; de Souza, E O; Wilson, J M; Carpenter, A L; Gilchrist, P; Lowery, R P; Averbuch, B; White, T M; Joy, J
2015-01-01
In spite of the well-known benefits that have been shown, few studies have looked at the practical applications of high-intensity interval training (HIIT) on athletic performance. This study investigated the effects of a HIIT program compared to traditional continuous endurance exercise training. 24 hockey players were randomly assigned to either a continuous or high-intensity interval group during a 4-week training program. The interval group (IG) was involved in a periodized HIIT program. The continuous group (CG) performed moderate intensity cycling for 45-60 min at an intensity that was 65% of their calculated heart rate reserve. Body composition, muscle thickness, anaerobic power, and on-ice measures were assessed pre- and post-training. Muscle thickness was significantly greater in IG (p=0.01) when compared to CG. The IG had greater values for both ∆ peak power (p<0.003) and ∆ mean power (p<0.02). Additionally, IG demonstrated a faster ∆ sprint (p<0.02) and a trend (p=0.08) for faster ∆ endurance test time to completion for IG. These results indicate that hockey players may utilize short-term HIIT to elicit positive effects in muscle thickness, power and on-ice performance. © Georg Thieme Verlag KG Stuttgart · New York.
Estimation of crystallinity in isotropic isotactic polypropylene with Raman spectroscopy.
Minogianni, Chrysa; Gatos, Konstantinos G; Galiotis, Costas
2005-09-01
The Raman spectrum of isotactic polypropylene (iPP) has been found to exhibit vibrational peaks in the region of 750 to 880 cm(-1) that are sensitive to the degree of crystallinity. These features are broadly assigned to various modes of methyl group rocking, rho(CH2), and there have been various attempts to assess crystallinity based on the integrated intensities of these bands. Various vibrational analyses performed in the past in combination with experimental studies have concluded that the presence of crystalline order with trans-gauche conformation gives rise to a peak at 809 cm(-1), which is assigned to a rho(CH2) mode coupled with the skeletal stretching mode. However, the presence of additional peaks at 830 cm(-1), 841 cm(-1), and 854 cm(-1), within the same envelope, have been the subject of controversy. In this work isotropic films of iPP derived from the same precursor of identical tacticity have been subjected to various degrees of annealing and the integrated intensities of the Raman bands were measured. The results showed that true 3d crystallinity in isotropic iPP can only be expressed by the 809 cm(-1) band whereas the band at 841 cm(-1) corresponds to an uncoupled rho(CH2) fundamental mode and thus is a measure of the amorphous content. The less intense satellite bands at 830 cm(-1) and 854 cm(-1) of solid iPP cannot be distinguished from the 841 cm(-1) band in the melt and are generally considered as intermediate phases possibly related to non-crystalline components with 3(1)-helical conformations. Independent differential scanning calorimetry (DSC) crystallinity measurements were in broad agreement with the Raman measurements based on the normalized intensity of the 809 cm(-1) Raman band. By comparing the Raman with the DSC data a new value for the theoretical heat of fusion for the 100% crystalline iPP has been proposed.
Two-peak structure in the K-edge RIXS spectra of a spatially frustrated Heisenberg antiferromagnet
NASA Astrophysics Data System (ADS)
Datta, Trinanjan; Luo, Cheng; Yao, Dao-Xin
2014-03-01
Quantum fluctuations due to spatial anisotropy and strong magnetic frustration lead to the formation of a two-peak structure in the K-edge bimagnon RIXS intensity spectra of a Jx-Jy-J2 Heisenberg model on a square lattice. We compute the RIXS intensity, including up to first order 1/S spin wave expansion correction, using the Bethe-Salpeter equation within the ladder approximation scheme. The two-peak feature occurs in both the antiferromagnetic phase and the collinear antiferromagnetic phase. A knowledge of the peak splitting energy from both magnetically ordered regime can provide experimentalists with an alternative means to measure and study the effects of local microscopic exchange constants. Cottrell Research Corporation, NSFC-11074310, NSFC-11275279, Specialized Research Fund for the Doctoral Program of Higher Education.
Lactation curves of dairy camels in an intensive system.
Musaad, Abdelgadir; Faye, Bernard; Nikhela, Abdelmoneim Abu
2013-04-01
Weekly milk records of 47 she-camels in a multibreed dairy camel herd were collected for over a period of 5 years. A total of 72 lactation curves were defined, and relationships with parity, calving season, lactation length, milk production level, following lactations, and dam weight were analyzed. Overall mean values were milk yield up to 12 months, 1,970 ± 790 l; lactation length, 12.5 months; persistency, 94.7 %; weekly peak yield, 50.7 l; monthly peak yield, 220 ± 90 l; and the number of weeks to reach peak yield, 28. The highest productivity was recorded in summer with a weekly mean of 48.2 ± 19.4 l, compared with 34.1 ± 16.3 l in winter. The highest average yield recorded was for camels at sixth parity, whereas the highest weekly peak was at eighth parity, and highest persistency at fifth parity. Camels that calved during the cold months (November to February) were most productives, with the highest persistency, peak yield, and longest lactation length. Four types of curves were identified corresponding to different parities and milk yield levels. Based on these data, specific models for camels are proposed.
Probabilistic peak detection in CE-LIF for STR DNA typing.
Woldegebriel, Michael; van Asten, Arian; Kloosterman, Ate; Vivó-Truyols, Gabriel
2017-07-01
In this work, we present a novel probabilistic peak detection algorithm based on a Bayesian framework for forensic DNA analysis. The proposed method aims at an exhaustive use of raw electropherogram data from a laser-induced fluorescence multi-CE system. As the raw data are informative up to a single data point, the conventional threshold-based approaches discard relevant forensic information early in the data analysis pipeline. Our proposed method assigns a posterior probability reflecting the data point's relevance with respect to peak detection criteria. Peaks of low intensity generated from a truly existing allele can thus constitute evidential value instead of fully discarding them and contemplating a potential allele drop-out. This way of working utilizes the information available within each individual data point and thus avoids making early (binary) decisions on the data analysis that can lead to error propagation. The proposed method was tested and compared to the application of a set threshold as is current practice in forensic STR DNA profiling. The new method was found to yield a significant improvement in the number of alleles identified, regardless of the peak heights and deviation from Gaussian shape. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Excitation energy dependent Raman spectrum of MoSe2
Nam, Dahyun; Lee, Jae-Ung; Cheong, Hyeonsik
2015-01-01
Raman investigation of MoSe2 was carried out with eight different excitation energies. Seven peaks, including E1g, A1g, E2g1, and A2u2 peaks are observed in the range of 100–400 cm−1. The phonon modes are assigned by comparing the peak positions with theoretical calculations. The intensities of the peaks are enhanced at different excitation energies through resonance with different optical transitions. The A1g mode is enhanced at 1.58 and 3.82 eV, which are near the A exciton energy and the band-to-band transition between higher energy bands, respectively. The E2g1 mode is strongly enhanced with respect to the A1g mode for the 2.71- and 2.81-eV excitations, which are close to the C exciton energy. The different enhancements of the A1g and E2g1 modes are explained in terms of the symmetries of the exciton states and the exciton-phonon coupling. Other smaller peaks including E1g and A2u2 are forbidden but appear due to the resonance effect near optical transition energies. PMID:26601614
Antal, A.; Alekseichuk, I.; Bikson, M.; Brockmöller, J.; Brunoni, A.R.; Chen, R.; Cohen, L.G.; Dowthwaite, G.; Ellrich, J.; Flöel, A.; Fregni, F.; George, M.S.; Hamilton, R.; Haueisen, J.; Herrmann, C.S.; Hummel, F.C.; Lefaucheur, J.P.; Liebetanz, D.; Loo, C.K.; McCaig, C.D.; Miniussi, C.; Miranda, P.C.; Moliadze, V.; Nitsche, M.A.; Nowak, R.; Padberg, F.; Pascual-Leone, A.; Poppendieck, W.; Priori, A.; Rossi, S.; Rossini, P.M.; Rothwell, J.; Rueger, M.A.; Ruffini, G.; Schellhorn, K.; Siebner, H.R.; Ugawa, Y.; Wexler, A.; Ziemann, U.; Hallett, M.; Paulus, W.
2018-01-01
Low intensity transcranial electrical stimulation (TES) in humans, encompassing transcranial direct current (tDCS), transcutaneous spinal Direct Current Stimulation (tsDCS), transcranial alternating current (tACS), and transcranial random noise (tRNS) stimulation or their combinations, appears to be safe. No serious adverse events (SAEs) have been reported so far in over 18,000 sessions administered to healthy subjects, neurological and psychiatric patients, as summarized here. Moderate adverse events (AEs), as defined by the necessity to intervene, are rare, and include skin burns with tDCS due to suboptimal electrode-skin contact. Very rarely mania or hypomania was induced in patients with depression (11 documented cases), yet a causal relationship is difficult to prove because of the low incidence rate and limited numbers of subjects in controlled trials. Mild AEs (MAEs) include headache and fatigue following stimulation as well as prickling and burning sensations occurring during tDCS at peak-to-baseline intensities of 1–2 mA and during tACS at higher peak-to-peak intensities above 2 mA. The prevalence of published AEs is different in studies specifically assessing AEs vs. those not assessing them, being higher in the former. AEs are frequently reported by individuals receiving placebo stimulation. The profile of AEs in terms of frequency, magnitude and type is comparable in healthy and clinical populations, and this is also the case for more vulnerable populations, such as children, elderly persons, or pregnant women. Combined interventions (e.g., co-application of drugs, electrophysiological measurements, neuroimaging) were not associated with further safety issues. Safety is established for low-intensity ‘conventional’ TES defined as <4 mA, up to 60 min duration per day. Animal studies and modeling evidence indicate that brain injury could occur at predicted current densities in the brain of 6.3–13 A/m2 that are over an order of magnitude above those produced by tDCS in humans. Using AC stimulation fewer AEs were reported compared to DC. In specific paradigms with amplitudes of up to 10 mA, frequencies in the kHz range appear to be safe. In this paper we provide structured interviews and recommend their use in future controlled studies, in particular when trying to extend the parameters applied. We also discuss recent regulatory issues, reporting practices and ethical issues. These recommendations achieved consensus in a meeting, which took place in Göttingen, Germany, on September 6–7, 2016 and were refined thereafter by email correspondence. PMID:28709880
Antal, A; Alekseichuk, I; Bikson, M; Brockmöller, J; Brunoni, A R; Chen, R; Cohen, L G; Dowthwaite, G; Ellrich, J; Flöel, A; Fregni, F; George, M S; Hamilton, R; Haueisen, J; Herrmann, C S; Hummel, F C; Lefaucheur, J P; Liebetanz, D; Loo, C K; McCaig, C D; Miniussi, C; Miranda, P C; Moliadze, V; Nitsche, M A; Nowak, R; Padberg, F; Pascual-Leone, A; Poppendieck, W; Priori, A; Rossi, S; Rossini, P M; Rothwell, J; Rueger, M A; Ruffini, G; Schellhorn, K; Siebner, H R; Ugawa, Y; Wexler, A; Ziemann, U; Hallett, M; Paulus, W
2017-09-01
Low intensity transcranial electrical stimulation (TES) in humans, encompassing transcranial direct current (tDCS), transcutaneous spinal Direct Current Stimulation (tsDCS), transcranial alternating current (tACS), and transcranial random noise (tRNS) stimulation or their combinations, appears to be safe. No serious adverse events (SAEs) have been reported so far in over 18,000 sessions administered to healthy subjects, neurological and psychiatric patients, as summarized here. Moderate adverse events (AEs), as defined by the necessity to intervene, are rare, and include skin burns with tDCS due to suboptimal electrode-skin contact. Very rarely mania or hypomania was induced in patients with depression (11 documented cases), yet a causal relationship is difficult to prove because of the low incidence rate and limited numbers of subjects in controlled trials. Mild AEs (MAEs) include headache and fatigue following stimulation as well as prickling and burning sensations occurring during tDCS at peak-to-baseline intensities of 1-2mA and during tACS at higher peak-to-peak intensities above 2mA. The prevalence of published AEs is different in studies specifically assessing AEs vs. those not assessing them, being higher in the former. AEs are frequently reported by individuals receiving placebo stimulation. The profile of AEs in terms of frequency, magnitude and type is comparable in healthy and clinical populations, and this is also the case for more vulnerable populations, such as children, elderly persons, or pregnant women. Combined interventions (e.g., co-application of drugs, electrophysiological measurements, neuroimaging) were not associated with further safety issues. Safety is established for low-intensity 'conventional' TES defined as <4mA, up to 60min duration per day. Animal studies and modeling evidence indicate that brain injury could occur at predicted current densities in the brain of 6.3-13A/m 2 that are over an order of magnitude above those produced by tDCS in humans. Using AC stimulation fewer AEs were reported compared to DC. In specific paradigms with amplitudes of up to 10mA, frequencies in the kHz range appear to be safe. In this paper we provide structured interviews and recommend their use in future controlled studies, in particular when trying to extend the parameters applied. We also discuss recent regulatory issues, reporting practices and ethical issues. These recommendations achieved consensus in a meeting, which took place in Göttingen, Germany, on September 6-7, 2016 and were refined thereafter by email correspondence. Copyright © 2017 International Federation of Clinical Neurophysiology. All rights reserved.
Kang, Qi; Shen, Qirui; Zhang, Ping; Wang, Honghai; Sun, Yan; Shen, Dazhong
2018-02-20
Quartz crystal microbalance (QCM) is an important tool to detect in real time the mass change at the nanogram level. However, for a QCM operated in the liquid phase, the Sauerbrey equation is usually disturbed by the changes in liquid properties and the longitudinal wave effect. Herein, we report another unfound associated high-frequency resonance (HFR) model for the QCM, with the intensity 2 orders of magnitude higher than that of the fundamental peak in the liquid phase. The HFR model exhibits obvious impact on the response of QCM in the thickness-shear model (TSM), especially for overtones. The frequency of HFR peak is decreased dramatically with increasing conductivity or permittivity of the liquid phase, resulting in considerable additional frequency shifts in the TSM as baseline drift. Compared to that with a faraway HFR peak, the overlapping of HFR peak to a TSM overtone results in the frequency shifts of ±50-70 kHz with its intensity enhancement by 3 orders of magnitude in the later. The HFR behavior is explained by an equivalent circuit model including leading wire inductance, liquid inductance, and static capacitance of QCM. Taking into account the HFR model, the positive frequency shifts of the QCM at high overtones during the cell adhesion process is understandable. Combining the TSM and HFR is an effective way to improve the stability of QCM and provides more reliable information from the responses of QCM. The HFR may have potential application in chemical and biological sensors.
Stochastic P-bifurcation and stochastic resonance in a noisy bistable fractional-order system
NASA Astrophysics Data System (ADS)
Yang, J. H.; Sanjuán, Miguel A. F.; Liu, H. G.; Litak, G.; Li, X.
2016-12-01
We investigate the stochastic response of a noisy bistable fractional-order system when the fractional-order lies in the interval (0, 2]. We focus mainly on the stochastic P-bifurcation and the phenomenon of the stochastic resonance. We compare the generalized Euler algorithm and the predictor-corrector approach which are commonly used for numerical calculations of fractional-order nonlinear equations. Based on the predictor-corrector approach, the stochastic P-bifurcation and the stochastic resonance are investigated. Both the fractional-order value and the noise intensity can induce an stochastic P-bifurcation. The fractional-order may lead the stationary probability density function to turn from a single-peak mode to a double-peak mode. However, the noise intensity may transform the stationary probability density function from a double-peak mode to a single-peak mode. The stochastic resonance is investigated thoroughly, according to the linear and the nonlinear response theory. In the linear response theory, the optimal stochastic resonance may occur when the value of the fractional-order is larger than one. In previous works, the fractional-order is usually limited to the interval (0, 1]. Moreover, the stochastic resonance at the subharmonic frequency and the superharmonic frequency are investigated respectively, by using the nonlinear response theory. When it occurs at the subharmonic frequency, the resonance may be strong and cannot be ignored. When it occurs at the superharmonic frequency, the resonance is weak. We believe that the results in this paper might be useful for the signal processing of nonlinear systems.
NASA Technical Reports Server (NTRS)
Krause, L. Habsh; Gilchrist, B. E.; Nishikawa, Ken-Ichi
2013-01-01
Relativisitic electron precipitation (REP) events occur when beams or bunches of relativistic electrons of magnetospheric origin enter the Earth's atmosphere, typically at auroral latitudes. REP events are associated with a variety of space weather effects, including production of transitional and bremsstrahlung radiation, catalytic depletion of stratospheric ozone, and scintillation of transionospheric radio waves. This study examines the intensities of x-rays produced at airliner, manned balloon, and space reuseable launch vehicles (sRLVs). The monoenergetic beam is modeled in cylindrical symetry using the paraxial ray equation. Bremsstrahlung photon production is calculated using the traditional Sauter-Elwert cross-section, providing x-ray emission spectra differential in energy and angle. Attenuation is computed for a plane-stratified standard atmosphere, and the loss processes include photoionization, Rayleigh and Compton scattering, electron-positron pair production, and photonuclear interaction. Peak altitudes of electron energy deposition and bremsstrahlung x-ray production were calculated for beams of energies from 1 MeV through 100 MeV. The altitude peak of bremsstrahlung deposition was consistently and significantly lower that that of the electron deposition due to the longer mean free paths of x-rays compared to electrons within the atmosphere. For example, for a nadir-directed monoenergetic 5 MeV beam, the peak deposition altitude was calculated to be 42 km, but the resulting bremsstrahlung deposition peaked at 25 km. This has implications for crew and passenger safety, especially with the growth of the space tourism industry. A survey of results covering the 1-100 MeV spectrum for the three altitude ranges of interest will be presented.
Zinner, Christoph; Heilemann, Ilka; Kjendlie, Per-Ludvik; Holmberg, Hans-Christer; Mester, Joachim
2010-01-01
Training volume in swimming is usually very high when compared to the relatively short competition time. High-intensity interval training (HIIT) has been demonstrated to improve performance in a relatively short training period. The main purpose of the present study was to examine the effects of a 5-week HIIT versus high-volume training (HVT) in 9–11-year-old swimmers on competition performance, 100 and 2,000 m time (T100 m and T2,000 m), VO2peak and rate of maximal lactate accumulation (Lacmax). In a 5-week crossover study, 26 competitive swimmers with a mean (SD) age of 11.5 ± 1.4 years performed a training period of HIIT and HVT. Competition (P < 0.01; effect size = 0.48) and T2,000 m (P = 0.04; effect size = 0.21) performance increased following HIIT. No changes were found in T100 m (P = 0.20). Lacmax increased following HIIT (P < 0.01; effect size = 0.43) and decreased after HVT (P < 0.01; effect size = 0.51). VO2peak increased following both interventions (P < 0.05; effect sizes = 0.46–0.57). The increases in competition performance, T2,000 m, Lacmax and VO2peak following HIIT were achieved in significantly less training time (~2 h/week). PMID:20683609
NASA Astrophysics Data System (ADS)
Nakajima, Akio; Arai, Tsunenori; Kikuchi, Makoto; Iwaya, Akimi; Arai, Katsuyuki; Inazaki, Satoshi; Takaoka, Takatsugu; Kato, Masayoshi
1995-05-01
A simple laser ablation monitoring during burn scar removal by KrF laser irradiation was studied to control laser fluence in real-time. Because, to obtain suitable surface for auto skin-graft, the laser fluence should be precisely controlled at each laser shot. We employed simple probe transmission method which could detect ejected material/phenomena from irradiated surface. The time-course of measured probe intensity contained a couple of attenuated peaks, which might corresponded to a shock wave front and debris plume. The delay time from laser irradiation to the debris plume peak appearance varied with the ablation fluence. The delay time of 1 J/cm2 (near ablation threshold) case prolonged 25% from 8 J/cm2 (far above threshold) case. Therefore, we think the delay time measurement by means of the simple probe transmission method may be available to attain the laser fluence control for nonuniform burn scar removal. The time-resolved photography and probe reflection method were also studied to understand the measured time-course of the transmitted probe intensity.
Dark-field transmission electron microscopy and the Debye-Waller factor of graphene
Hubbard, William A.; White, E. R.; Dawson, Ben; Lodge, M. S.; Ishigami, Masa; Regan, B. C.
2014-01-01
Graphene's structure bears on both the material's electronic properties and fundamental questions about long range order in two-dimensional crystals. We present an analytic calculation of selected area electron diffraction from multi-layer graphene and compare it with data from samples prepared by chemical vapor deposition and mechanical exfoliation. A single layer scatters only 0.5% of the incident electrons, so this kinematical calculation can be considered reliable for five or fewer layers. Dark-field transmission electron micrographs of multi-layer graphene illustrate how knowledge of the diffraction peak intensities can be applied for rapid mapping of thickness, stacking, and grain boundaries. The diffraction peak intensities also depend on the mean-square displacement of atoms from their ideal lattice locations, which is parameterized by a Debye-Waller factor. We measure the Debye-Waller factor of a suspended monolayer of exfoliated graphene and find a result consistent with an estimate based on the Debye model. For laboratory-scale graphene samples, finite size effects are sufficient to stabilize the graphene lattice against melting, indicating that ripples in the third dimension are not necessary. PMID:25242882
NASA Astrophysics Data System (ADS)
Anderson, Benjamin; Buah-Bassuah, Paul K.; Tetteh, Jonathan P.
2004-07-01
The use of violet laser-induced chlorophyll fluorescence (LICF) emission spectra to monitor the growth of five varieties of cowpea in the University of Cape Coast Botanical Garden is presented. Radiation from a continuous-wave violet laser diode emitting at 396 nm through a fibre is closely incident on in vivo leaves of cowpea to excite chlorophyll fluorescence, which is detected by an integrated spectrometer with CCD readout. The chlorophyll fluorescence spectra with peaks at 683 and 731 nm were used for growth monitoring of the cowpea plants over three weeks and analysed using Gaussian spectral functions with curve fitted parameters to determine the peak positions, area under the spectral curve and the intensity ratio F683/F731. The variation in the intensity ratio of the chlorophyll bands showed sensitive changes indicating the photosynthetic activity of the cowpea varieties. A discussion of the fluorescence result as compared to conventional assessment is presented with regard to discrimination between the cowpea varieties in terms of crop yield performance.
Dark-field transmission electron microscopy and the Debye-Waller factor of graphene.
Shevitski, Brian; Mecklenburg, Matthew; Hubbard, William A; White, E R; Dawson, Ben; Lodge, M S; Ishigami, Masa; Regan, B C
2013-01-15
Graphene's structure bears on both the material's electronic properties and fundamental questions about long range order in two-dimensional crystals. We present an analytic calculation of selected area electron diffraction from multi-layer graphene and compare it with data from samples prepared by chemical vapor deposition and mechanical exfoliation. A single layer scatters only 0.5% of the incident electrons, so this kinematical calculation can be considered reliable for five or fewer layers. Dark-field transmission electron micrographs of multi-layer graphene illustrate how knowledge of the diffraction peak intensities can be applied for rapid mapping of thickness, stacking, and grain boundaries. The diffraction peak intensities also depend on the mean-square displacement of atoms from their ideal lattice locations, which is parameterized by a Debye-Waller factor. We measure the Debye-Waller factor of a suspended monolayer of exfoliated graphene and find a result consistent with an estimate based on the Debye model. For laboratory-scale graphene samples, finite size effects are sufficient to stabilize the graphene lattice against melting, indicating that ripples in the third dimension are not necessary.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Matzke, Melissa M.; Brown, Joseph N.; Gritsenko, Marina A.
2013-02-01
Liquid chromatography coupled with mass spectrometry (LC-MS) is widely used to identify and quantify peptides in complex biological samples. In particular, label-free shotgun proteomics is highly effective for the identification of peptides and subsequently obtaining a global protein profile of a sample. As a result, this approach is widely used for discovery studies. Typically, the objective of these discovery studies is to identify proteins that are affected by some condition of interest (e.g. disease, exposure). However, for complex biological samples, label-free LC-MS proteomics experiments measure peptides and do not directly yield protein quantities. Thus, protein quantification must be inferred frommore » one or more measured peptides. In recent years, many computational approaches to relative protein quantification of label-free LC-MS data have been published. In this review, we examine the most commonly employed quantification approaches to relative protein abundance from peak intensity values, evaluate their individual merits, and discuss challenges in the use of the various computational approaches.« less
Baudisch, M; Hemmer, M; Pires, H; Biegert, J
2014-10-15
The performance of potassium niobate (KNbO₃), MgO-doped periodically poled lithium niobate (MgO:PPLN), and potassium titanyl arsenate (KTA) were experimentally compared for broadband mid-wave infrared parametric amplification at a high repetition rate. The seed pulses, with an energy of 6.5 μJ, were amplified using 410 μJ pump energy at 1064 nm to a maximum pulse energy of 28.9 μJ at 3 μm wavelength and at a 160 kHz repetition rate in MgO:PPLN while supporting a transform limited duration of 73 fs. The high average powers of the interacting beams used in this study revealed average power-induced processes that limit the scaling of optical parametric amplification in MgO:PPLN; the pump peak intensity was limited to 3.8 GW/cm² due to nonpermanent beam reshaping, whereas in KNbO₃ an absorption-induced temperature gradient in the crystal led to permanent internal distortions in the crystal structure when operated above a pump peak intensity of 14.4 GW/cm².
Lorah, M.M.; Voytek, M.A.; Kirshtein, J.
2000-01-01
Additional microcosm experiments with the wetland sediment and groundwater at the Aberdeen Proving Ground, MD, site was presented to assist in elucidating the conditions under which these potentially competing biotic and abiotic degradation reactions for 1,1,2,2-tetrachloroethane (PCA) occur in the environment and to evaluate potential seasonal changes in degradation reactions. PCA concentration decreased to below detection within 21 days in the March 1999 experiment, while PCA was still present at day 35 in the July 1999 experiment. Compared to March 1999 experiment, peak concentrations of all daughter products except trichloroethylene (TCE) were delayed in the July 1999 experiment. The relative intensity of the peaks was directly related to the biomass present for each fragment length (bp, base pair). The relative intensities were lower in sediment collected in August 1999 than in March 1999, especially in the bp size range of ??? 160??-240??. These microbial community analyses, along with the geochemical analyses of the microcosms, provide evidence that abiotic production of TCE from PCA degradation is more significant under conditions of low bacterial biomass in the wetland sediments.
Scattering of electromagnetic waves from a body over a random rough surface
NASA Astrophysics Data System (ADS)
Ripoll, J.; Madrazo, A.; Nieto-Vesperinas, M.
1997-02-01
A numerical study is made of the effect on the angular distribution of mean far field intensity due to the presence of an arbitrary body located over a random rough surface. It is found that the presence of the body decreases the coherent backscattering peak produced by the surface roughness. Also, for low dielectric constants, the reflected intensity is practically equal to the sum of the individual reflected intensities of the body and the surface respectively, namely, interaction between both bodies is almost negligible. The full interaction between object and surface only appears when both bodies are highly reflective. Results are compared with the case when the body is buried beneath the surface, and are illustrated with a 2-D calculation of a cylinder either partially immersed or above a 2-D rough profile.
Northwestern Pacific typhoon intensity controlled by changes in ocean temperatures.
Mei, Wei; Xie, Shang-Ping; Primeau, François; McWilliams, James C; Pasquero, Claudia
2015-05-01
Dominant climatic factors controlling the lifetime peak intensity of typhoons are determined from six decades of Pacific typhoon data. We find that upper ocean temperatures in the low-latitude northwestern Pacific (LLNWP) and sea surface temperatures in the central equatorial Pacific control the seasonal average lifetime peak intensity by setting the rate and duration of typhoon intensification, respectively. An anomalously strong LLNWP upper ocean warming has favored increased intensification rates and led to unprecedentedly high average typhoon intensity during the recent global warming hiatus period, despite a reduction in intensification duration tied to the central equatorial Pacific surface cooling. Continued LLNWP upper ocean warming as predicted under a moderate [that is, Representative Concentration Pathway (RCP) 4.5] climate change scenario is expected to further increase the average typhoon intensity by an additional 14% by 2100.
An updated climatology of explosive cyclones using alternative measures of cyclone intensity
NASA Astrophysics Data System (ADS)
Hanley, J.; Caballero, R.
2009-04-01
Using a novel cyclone tracking and identification method, we compute a climatology of explosively intensifying cyclones or ‘bombs' using the ERA-40 and ERA-Interim datasets. Traditionally, ‘bombs' have been identified using a central pressure deepening rate criterion (Sanders and Gyakum, 1980). We investigate alternative methods of capturing such extreme cyclones. These methods include using the maximum wind contained within the cyclone, and using a potential vorticity column measure within such systems, as a measure of intensity. Using the different measures of cyclone intensity, we construct and intercompare maps of peak cyclone intensity. We also compute peak intensity probability distributions, and assess the evidence for the bi-modal distribution found by Roebber (1984). Finally, we address the question of the relationship between storm intensification rate and storm destructiveness: are ‘bombs' the most destructive storms?
Nakata, Norio; Ohta, Tomoyuki; Nishioka, Makiko; Takeyama, Hiroshi; Toriumi, Yasuo; Kato, Kumiko; Nogi, Hiroko; Kamio, Makiko; Fukuda, Kunihiko
2015-11-01
This study was performed to evaluate the diagnostic utility of quantitative analysis of benign and malignant breast lesions using contrast-enhanced sonography. Contrast-enhanced sonography using the perflubutane-based contrast agent Sonazoid (Daiichi Sankyo, Tokyo, Japan) was performed in 94 pathologically proven palpable breast mass lesions, which could be depicted with B-mode sonography. Quantitative analyses using the time-intensity curve on contrast-enhanced sonography were performed in 5 region of interest (ROI) types (manually traced ROI and circular ROIs of 5, 10, 15, and 20 mm in diameter). The peak signal intensity, initial slope, time to peak, positive enhancement integral, and wash-out ratio were investigated in each ROI. There were significant differences between benign and malignant lesions in the time to peak (P < .05), initial slope (P < .001), and positive enhancement integral (P < .05) for the manual ROI. Significant differences were found between benign and malignant lesions in the time to peak (P < .05) for the 5-mm ROI; the time to peak (P < .05) and initial slope (P< .05) for the 10-mm ROI; absolute values of the peak signal intensity (P< .05), time to peak (P< .01), and initial slope (P< .005) for the 15-mm ROI; and the time to peak (P < .05) and initial slope (P < .05) for the 20-mm ROI. There were no statistically significant differences in any wash-out ratio values for the 5 ROI types. Kinetic analysis using contrast-enhanced sonography is useful for differentiation between benign and malignant breast lesions. © 2015 by the American Institute of Ultrasound in Medicine.
Auffhammer, Maximilian; Baylis, Patrick; Hausman, Catherine H.
2017-01-01
It has been suggested that climate change impacts on the electric sector will account for the majority of global economic damages by the end of the current century and beyond [Rose S, et al. (2014) Understanding the Social Cost of Carbon: A Technical Assessment]. The empirical literature has shown significant increases in climate-driven impacts on overall consumption, yet has not focused on the cost implications of the increased intensity and frequency of extreme events driving peak demand, which is the highest load observed in a period. We use comprehensive, high-frequency data at the level of load balancing authorities to parameterize the relationship between average or peak electricity demand and temperature for a major economy. Using statistical models, we analyze multiyear data from 166 load balancing authorities in the United States. We couple the estimated temperature response functions for total daily consumption and daily peak load with 18 downscaled global climate models (GCMs) to simulate climate change-driven impacts on both outcomes. We show moderate and heterogeneous changes in consumption, with an average increase of 2.8% by end of century. The results of our peak load simulations, however, suggest significant increases in the intensity and frequency of peak events throughout the United States, assuming today’s technology and electricity market fundamentals. As the electricity grid is built to endure maximum load, our findings have significant implications for the construction of costly peak generating capacity, suggesting additional peak capacity costs of up to 180 billion dollars by the end of the century under business-as-usual. PMID:28167756
NASA Astrophysics Data System (ADS)
Fujii, Kenta; Kanzaki, Ryo; Takamuku, Toshiyuki; Kameda, Yasuo; Kohara, Shinji; Kanakubo, Mitsuhiro; Shibayama, Mitsuhiro; Ishiguro, Shin-ichi; Umebayashi, Yasuhiro
2011-12-01
Short- and long-range liquid structures of [CnmIm+][TFSA-] with n = 2, 4, 6, 8, 10, and 12 have been studied by high-energy x-ray diffraction (HEXRD) and small-angle neutron scattering (SANS) experiments with the aid of MD simulations. Observed x-ray structure factor, S(Q), for the ionic liquids with the alkyl-chain length n > 6 exhibited a characteristic peak in the low-Q range of 0.2-0.4 Å -1, indicating the heterogeneity of their ionic liquids. SANS profiles IH(Q) and ID(Q) for the normal and the alkyl group deuterated ionic liquids, respectively, showed significant peaks for n = 10 and 12 without no form factor component for large spherical or spheroidal aggregates like micelles in solution. The peaks for n = 10 and 12 evidently disappeared in the difference SANS profiles ΔI(Q) [=ID(Q) - IH(Q)], although that for n = 12 slightly remained. This suggests that the long-range correlations originated from the alkyl groups hardly contribute to the low-Q peak intensity in SANS. To reveal molecular origin of the low-Q peak, we introduce here a new function; x-ray structure factor intensity at a given Q as a function of r, SQpeak(r). The SQpeak(r) function suggests that the observed low-Q peak intensity depending on n is originated from liquid structures at two r-region of 5-8 and 8-15 Å for all ionic liquids examined except for n = 12. Atomistic MD simulations are consistent with the HEXRD and SANS experiments, and then we discussed the relationship between both variations of low-Q peak and real-space structure with lengthening the alkyl group of the CnmIm.
High pressure effects in high-field asymmetric waveform ion mobility spectrometry.
Wang, Yonghuan; Wang, Xiaozhi; Li, Lingfen; Chen, Chilai; Xu, Tianbai; Wang, Tao; Luo, Jikui
2016-08-30
High-Field Asymmetric Waveform Ion Mobility Spectrometry (FAIMS) is an analytical technique based on the principle of non-linear electric field dependence of coefficient of mobility of ions for separation that was originally conceived in the Soviet Union in the early 1980s. Being well developed over the past decades, FAIMS has become an efficient method for the separation and characterization of gas-phase ions at ambient pressure, often in air, to detect trace amounts of chemical species including explosives, toxic chemicals, chemical warfare agents and other compounds. However the resolution of FAIMS and ion separation capability need to be improved for more applications of the technique. The effects of above-ambient pressure varying from 1 to 3 atm on peak position, resolving power, peak width, and peak intensity are investigated theoretically and experimentally using micro-fabricated planar FAIMS in purified air. Peak positions, varying with pressure in a way as a function of dispersion voltage, could be simplified by expressing both compensation and dispersion fields in Townsend units for E/N, the ratio of electric field intensity (E) to the gas number density (N). It is demonstrated that ion Townsend-scale peak positions remain unchanged for a range of pressures investigated, implying that the higher the pressure is, stronger compensation and separation fields are needed within limits of air breakdown field. Increase in pressure is found to separate ions that could not be distinguished in ambient pressure, which could be interpreted as the differentials of ions' peak compensation voltage expanded wider than the dilation of peak widths leading to resolving power enhancement with pressure. Increase in pressure can also result in an increase in peak intensity. Copyright © 2016 John Wiley & Sons, Ltd.
Oxidative stress does not influence local sweat rate during high-intensity exercise.
Meade, Robert D; Fujii, Naoto; Poirier, Martin P; Boulay, Pierre; Sigal, Ronald J; Kenny, Glen P
2018-02-01
What is the central question of this study? We evaluated whether oxidative stress attenuates the contribution of nitric oxide to sweating during high-intensity exercise. What is the main finding and its importance? In contrast to our previous report of an oxidative stress-mediated reduction in nitric oxide-dependent cutaneous vasodilatation in this cohort during intense exercise, we demonstrated no influence of local ascorbate administration on the sweating response during moderate- (∼51% peak oxygen uptake) or high-intensity exercise (∼72% peak oxygen uptake). These new findings provide important mechanistic insight into how exercise-induced oxidative stress impacts sudomotor activity. Nitric oxide (NO)-dependent sweating is diminished during high- but not moderate-intensity exercise. We evaluated whether this impairment stems from increased oxidative stress during high-intensity exercise. On two separate days, 11 young (24 ± 4 years) men cycled in the heat (35°C) at a moderate [500 W; 52 ± 6% peak oxygen uptake (V̇O2 peak )] or high (700 W; 71 ± 5% V̇O2 peak ) rate of metabolic heat production. Each session included two 30 min exercise bouts separated by a 20 min recovery period. Local sweat rate was monitored at four forearm skin sites continuously perfused via intradermal microdialysis with the following: (i) lactated Ringer solution (Control); (ii) 10 mm ascorbate (Ascorbate; non-selective antioxidant); (iii) 10 mm N G -nitro-l-arginine methyl ester (l-NAME; NO synthase inhibitor); or (iv) 10 mm ascorbate plus 10 mm l-NAME (Ascorbate + l-NAME). During moderate exercise, sweat rate was attenuated at the l-NAME and Ascorbate + l-NAME sites (both ∼1.0 mg min -1 cm -2 ; all P < 0.05) but not at the Ascorbate site (∼1.1 mg min -1 cm -2 ; both P ≥ 0.28) in comparison to the Control site (∼1.1 mg min -1 cm -2 ). However, no differences were observed between treatment sites (∼1.4 mg min -1 cm -2 ; P = 0.75) during high-intensity exercise. We conclude that diminished NO-dependent sweating during intense exercise occurs independent of oxidative stress. © 2017 The Authors. Experimental Physiology © 2017 The Physiological Society.
Vibrational dynamics and boson peak in a supercooled polydisperse liquid.
Abraham, Sneha Elizabeth; Bagchi, Biman
2010-03-01
Vibrational density of states (VDOS) in a supercooled polydisperse liquid is computed by diagonalizing the Hessian matrix evaluated at the potential energy minima for systems with different values of polydispersity. An increase in polydispersity leads to an increase in the relative population of localized high-frequency modes. At low frequencies, the density of states shows an excess compared to the Debye squared-frequency law, which has been identified with the boson peak. The height of the boson peak increases with polydispersity and shows a rather narrow sensitivity to changes in temperature. While the modes comprising the boson peak appear to be largely delocalized, there is a sharp drop in the participation ratio of the modes that exist just below the boson peak indicative of the quasilocalized nature of the low-frequency vibrations. Study of the difference spectrum at two different polydispersity reveals that the increase in the height of boson peak is due to a population shift from modes with frequencies above the maximum in the VDOS to that below the maximum, indicating an increase in the fraction of the unstable modes in the system. The latter is further supported by the facilitation of the observed dynamics by polydispersity. Since the strength of the liquid increases with polydispersity, the present result provides an evidence that the intensity of boson peak correlates positively with the strength of the liquid, as observed earlier in many experimental systems.
The quantum interference effects in the SC II 4247 Å line of the second solar spectrum
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smitha, H. N.; Nagendra, K. N.; Stenflo, J. O.
2014-10-10
The Sc II 4247 Å line formed in the chromosphere is one of the lines well known, like the Na I D{sub 2} and Ba II D{sub 2}, for its prominent triple-peak structure in Q/I and the underlying quantum interference effects governing it. In this paper, we try to study the nature of this triple-peak structure using the theory of F-state interference including the effects of partial frequency redistribution (PRD) and radiative transfer (RT). We compare our results with the observations taken in a quiet region near the solar limb. In spite of accounting for PRD and RT effects, itmore » has not been possible to reproduce the observed triple-peak structure in Q/I. While the two wing PRD peaks (on either side of central peak) and the near wing continuum can be reproduced, the central peak is completely suppressed by the enhanced depolarization resulting from the hyperfine structure splitting. This suppression remains for all the tested widely different one-dimensional model atmospheres or for any multi-component combinations of them. While multidimensional RT effects may improve the fit to the intensity profiles, they do not appear capable of explaining the enigmatic central Q/I peak. This leads us to suspect that some aspect of quantum physics is missing.« less
2011-02-18
environmental interferents selected for this study included dolomitic limestone (Lime, NIST Standard Reference Materials, Catalog No. SRM 88b) and ovalbumin...emission lines due solely to substrates or interferents can be ignored. As in previous studies by our group, the background-corrected peak ...calculated by adding the intensi- ties of the emission lines at 486 and 656 nm); the summed intensities were normalized to the total peak intensity of the
MALDI Mass Spectrometry of Fullero[C60]tetrahydropyridines
NASA Astrophysics Data System (ADS)
Fatkullina, A. F.; Yanybin, V. M.; Asfandiarov, N. L.; Tuktarov, A. R.; Khalilov, L. M.
2018-07-01
Mass spectra of positive and negative MALDI ions of the series of fullero[C60] tetrahydropyridines with different substituents in a heterocycle are systematically studied for the first time. All mass spectra contain C60 fullerene peaks as a result of the reduction of fullero[C60]tetrahydropyridines. The intensities of the protonated molecular ions' [M + H]+ peaks are highest in the mass spectra of positive ions of the studied compounds, while molecular radical ion [M]+ is less intense. The intensities of the peaks of molecular radical ion [M]- are highest in the mass spectra of the negative ions. The [C60C2H5] ions formed during the decay of the molecular ions with the detachment of neutral nitrile molecules is characteristic of all compounds. Using DFT quantum-chemical calculations (PBE/3z), the energies of the highest (HOMO) and lowest unoccupied molecular orbitals (LUMO) are determined for fullero[C60]tetrahydropyridines with substituents in the heterocycle.
NASA Astrophysics Data System (ADS)
Aditya, M. R.; Hernina, R.; Rokhmatuloh
2017-12-01
Rapid development in Jakarta which generates more impervious surface has reduced the amount of rainfall infiltration into soil layer and increases run-off. In some events, continuous high rainfall intensity could create sudden flood in Jakarta City. This article used rainfall data of Jakarta during 10 February 2015 to compute rainfall intensity and then interpolate it with ordinary kriging technique. Spatial distribution of rainfall intensity then overlaid with run-off coefficient based on certain land use type of the study area. Peak run-off within each cell resulted from hydrologic rational model then summed for the whole study area to generate total peak run-off. For this study area, land use types consisted of 51.9 % industrial, 37.57% parks, and 10.54% residential with estimated total peak run-off 6.04 m3/sec, 0.39 m3/sec, and 0.31 m3/sec, respectively.
Feng, Dan; Wang, Yanwei; Lu, Tiegang; Zhang, Zhiguo; Han, Xiao
2017-01-01
Plant leaves exhibit differentiated patterns of photosynthesis rates under diurnal light regulation. Maize leaves show a single-peak pattern without photoinhibition at midday when the light intensity is maximized. This mechanism contributes to highly efficient photosynthesis in maize leaves. To understand the molecular basis of this process, an isobaric tag for relative and absolute quantitation (iTRAQ)-based proteomics analysis was performed to reveal the dynamic pattern of proteins related to photosynthetic reactions. Steady, single-peak and double-peak protein expression patterns were discovered in maize leaves, and antenna proteins in these leaves displayed a steady pattern. In contrast, the photosystem, carbon fixation and citrate pathways were highly controlled by diurnal light intensity. Most enzymes in the limiting steps of these pathways were major sites of regulation. Thus, maize leaves optimize photosynthesis and carbon fixation outside of light harvesting to adapt to the changes in diurnal light intensity at the protein level.
Windsor, Mark T.; Bailey, Tom G.; Perissiou, Maria; Meital, Lara; Golledge, Jonathan; Russell, Fraser D.; Askew, Christopher D.
2018-01-01
Markers of chronic inflammation increase with aging, and are associated with cardiovascular disease prevalence and mortality. Increases in fitness with exercise training have been associated with lower circulating concentrations of cytokines known to have pro-inflammatory actions (such as interleukin-6 [IL-6]) and higher circulating concentrations of anti-inflammatory cytokines (interleukin-10 [IL-10]). However, the effect of cardiorespiratory fitness on acute cytokine responses to a single bout of exercise in healthy older individuals is unknown. We compared the response of plasma cytokines IL-6, tumor necrosis factor-alpha (TNF-α) and IL-10 to a bout of moderate-intensity continuous and higher-intensity interval exercise between older individuals with higher and lower levels of cardiorespiratory fitness. Sixteen lower-fit (VO2peak: 22.6±2.8 mL.kg−1.min−1) and fourteen higher-fit participants (VO2peak: 37.4±5.9 mL.kg−1.min−1) completed three 24 min experimental protocols in a randomized order: (1) moderate-intensity continuous exercise (40% of peak power output [PPO]); (2) higher-intensity interval exercise (12 × 1 min intervals at 70% PPO separated by 1 min periods at 10% PPO); or (3) non-exercise control. Plasma cytokines were measured at rest, immediately after, and during 90 min of recovery following exercise or control. Plasma IL-6 concentrations at baseline were greater in the higher-fit compared to the lower-fit group (P = 0.02), with no difference in plasma IL-10 or TNF-α concentrations at baseline between groups. Plasma IL-6 and IL-10 concentrations in both groups increased immediately after all protocols (IL-6: P = 0.02, IL-10: P < 0.01). However, there was no difference in the IL-6 and IL-10 response between the exercise and non-exercise (control) protocols. After all protocols, no changes in plasma TNF-α concentrations were observed in either the higher- or lower-fit groups. In this study, basal concentrations of circulating IL-6 were elevated in older individuals with higher levels of cardiorespiratory fitness. However, changes in plasma cytokine concentrations after exercise were not different to changes after non-exercise control in both the lower- and higher-fit groups. PMID:29599722
Metabolic fingerprinting of lichen Usnea baileyi by Fourier transform infrared spectroscopy
NASA Astrophysics Data System (ADS)
Bakar, Siti Zaharah Abu; Latip, Jalifah; bin Din, Laily; Samsuddin, Mohd Wahid
2014-09-01
The lichen Usnea baileyi collected from different environments was characterised using Fourier transform infrared spectroscopy. This preliminary study was done to determine the effects of different environment populations on U. baileyi chemical composition. Results showed that the absorbance peaks of Golf Course 2 (GCU2) are more intense compared to Taman Awana (TA), Jalan Awana (JA) and Jalan Gohtong (JG). U. baileyi contains of dibenzofurans, depsides, depsidones, xanthones and terpenoids.
Improvements of high-power diode laser line generators open up new application fields
NASA Astrophysics Data System (ADS)
Meinschien, J.; Bayer, A.; Bruns, P.; Aschke, L.; Lissotschenko, V. N.
2009-02-01
Beam shaping improvements of line generators based on high power diode lasers lead to new application fields as hardening, annealing or cutting of various materials. Of special interest is the laser treatment of silicon. An overview of the wide variety of applications is presented with special emphasis of the relevance of unique laser beam parameters like power density and beam uniformity. Complementary to vision application and plastic processing, these new application markets become more and more important and can now be addressed by high power diode laser line generators. Herewith, a family of high power diode laser line generators is presented that covers this wide spectrum of application fields with very different requirements, including new applications as cutting of silicon or glass, as well as the beam shaping concepts behind it. A laser that generates a 5m long and 4mm wide homogeneous laser line is shown with peak intensities of 0.2W/cm2 for inspection of railway catenaries as well as a laser that generates a homogeneous intensity distribution of 60mm x 2mm size with peak intensities of 225W/cm2 for plastic processing. For the annealing of silicon surfaces, a laser was designed that generates an extraordinary uniform intensity distribution with residual inhomogeneities (contrast ratio) of less than 3% over a line length of 11mm and peak intensities of up to 75kW/cm2. Ultimately, a laser line is shown with a peak intensity of 250kW/cm2 used for cutting applications. Results of various application tests performed with the above mentioned lasers are discussed, particularly the surface treatment of silicon and the cutting of glass.
NASA Astrophysics Data System (ADS)
Koizumi, Hiroshi; Watabe, Junya; Sugiyama, Shin; Hirabayashi, Hideaki; Homma, Tetsuya
2018-06-01
The effect of the sintering temperature of Ce3+-doped Lu3Al5O12 (Ce-LuAG) phosphors on the emission and properties of the crystal structure was studied. A cathodoluminescence peak at 317 nm, which was assigned to lattice defects, was exhibited in addition to emission peaks at 508 and 540 nm for the Ce-LuAG phosphors. The intensities of the 317 nm emission peak for the phosphors with mean particle diameters of 5.0 and 10.0 µm formed at a low sintering temperature of 1430 °C were higher than those for the phosphors with mean particle diameters of 18.0 and 20.5 µm formed at a high sintering temperature of 1550 °C. In contrast, the electroluminescence spectra for fabricated white-light-emitting diodes (LEDs) using the phosphors revealed that the intensity of the peak at 540 nm was strong for the mean particle diameters of 18.0 and 20.5 µm. The intensity of the 540 nm peak, which is attributed to the 4f→5d transition of the Ce3+ activator, showed a dependence on the sintering temperature. The relationship between the optical properties and the lattice defects is discussed.
A Diffraction Method of Study of Thermal Quasiorder in a Finite Two-Dimensional Harmonic Lattice
NASA Astrophysics Data System (ADS)
Aranda, P.; Croset, B.
1995-09-01
Due to the non-existence of long-range order, the diffraction peaks of 2D-solids are considered to have a power-law shape g_p^{η-2}. Taking into account the finite size effects and calculating the powder average, we show that this power-law behaviour appears only for high q_p and then for very small intensities. It is therefore quite difficult and hazardous to characterise the quasiorder by using this asymptotic behaviour. Although the shape of the central part of the peak cannot be used to characterise the quasiorder, we show that, for a fairly good resolution, it is possible to determine η using this central part. This determination can be done irrespectively with the other details of the system by comparing the peak width to its value at low temperature, i.e., at low value of η. By using two diffraction peaks, we propose the simple relation: η(Q_{B_1})/Q_{B_1}^2=η(Q_{B_2})/Q_{B_2}^2 as a check of the two-dimensional quasiorder.
Noninvasive intracranial pressure measurement using infrasonic emissions from the tympanic membrane.
Stettin, Eduard; Paulat, Klaus; Schulz, Chris; Kunz, Ulrich; Mauer, Uwe Max
2011-06-01
We investigated whether ICP can be assessed by measuring infrasonic emissions from the tympanic membrane. An increase in ICP was induced in 22 patients with implanted ICP pressure sensors. ICP waveforms that were obtained invasively and continuously were compared with infrasonic emission waveforms. In addition, the noninvasive method was used in a control group of 14 healthy subjects. In a total of 83 measurements, the changes in ICP that were observed in response to different types of stimulation were detected in the waveforms obtained noninvasively as well as in those acquired invasively. Low ICP was associated with an initial high peak and further peaks with smaller amplitudes. High ICP was associated with a marked decrease in the number of peaks and in the difference between the amplitudes of the initial and last peaks. The assessment of infrasonic emissions, however, does not yet enable us to provide exact figures. It is conceivable that the assessment of infrasonic emissions will become suitable both as a screening tool and for the continuous monitoring of ICP in an intensive care environment.
Fernandez-Fernandez, Jaime; Sanz, David; Sarabia, Jose Manuel; Moya, Manuel
2017-01-01
To compare the effects of combining high-intensity training (HIT) and sport-specific drill training (MT) versus sportspecific drill training alone (DT) on fitness performance characteristics in young tennis players. Twenty young tennis players (14.8 ± 0.1 y) were assigned to either DT (n = 10) or MT (n = 10) for 8 wk. Tennis drills consisted of two 16- to 22-min on-court exercise sessions separated by 3 min of passive rest, while MT consisted of 1 sport-specific DT session and 1 HIT session, using 16-22 min of runs at intensities (90-95%) related to the velocity obtained in the 30-15 Intermittent Fitness Test (V IFT ) separated by 3 min of passive rest. Pre- and posttests included peak oxygen uptake (VO 2 peak), V IFT , speed (20 m, with 5- and 10-m splits), 505 Agility Test, and countermovement jump (CMJ). There were significant improvements after the training period in VO 2 peak (DT 2.4%, ES = moderate; MT 4.2%, ES = large) and V IFT (DT 2.2%, ES = small; MT 6.3%, ES = large) for both DT and MT, with no differences between training protocols. Results also showed a large increase in the 505 Agility Test after MT, while no changes were reported in the other tests (sprint and CMJ), either for MT or DT. Even though both training programs resulted in significant improvements in aerobic performance, a mixed program combining tennis drills and runs based on the V IFT led to greater gains and should be considered the preferred training method for improving aerobic power in young athletes.
Keteyian, Steven J; Hibner, Brooks A; Bronsteen, Kyle; Kerrigan, Dennis; Aldred, Heather A; Reasons, Lisa M; Saval, Mathew A; Brawner, Clinton A; Schairer, John R; Thompson, Tracey M S; Hill, Jason; McCulloch, Derek; Ehrman, Jonathon K
2014-01-01
We tested the hypothesis that higher-intensity interval training (HIIT) could be deployed into a standard cardiac rehabilitation (CR) setting and would result in a greater increase in cardiorespiratory fitness (ie, peak oxygen uptake, (·)VO₂) versus moderate-intensity continuous training (MCT). Thirty-nine patients participating in a standard phase 2 CR program were randomized to HIIT or MCT; 15 patients and 13 patients in the HIIT and MCT groups, respectively, completed CR and baseline and followup cardiopulmonary exercise testing. No patients in either study group experienced an event that required hospitalization during or within 3 hours after exercise. The changes in resting heart rate and blood pressure at followup testing were similar for both HIIT and MCT. (·)VO₂ at ventilatory-derived anaerobic threshold increased more (P < .05) with HIIT (3.0 ± 2.8 mL·kg⁻¹·min⁻¹) versus MCT (0.7 ± 2.2 mL·kg⁻¹·min⁻¹). During followup testing, submaximal heart rate at the end of stage 2 of the exercise test was significantly lower within both the HIIT and MCT groups, with no difference noted between groups. Peak (·)VO₂ improved more after CR in patients in HIIT versus MCT (3.6 ± 3.1 mL·kg⁻¹·min⁻¹ vs 1.7 ± 1.7 mL·kg⁻¹·min⁻¹; P < .05). Among patients with stable coronary heart disease on evidence-based therapy, HIIT was successfully integrated into a standard CR setting and, when compared to MCT, resulted in greater improvement in peak exercise capacity and submaximal endurance.
Carl, Daniel L; Boyne, Pierce; Rockwell, Bradley; Gerson, Myron; Khoury, Jane; Kissela, Brett; Dunning, Kari
2017-03-01
The purpose of this study was to assess safety via electrocardiographic (ECG), blood pressure (BP), heart rate (HR), and orthopedic responses to 3 different high-intensity interval training (HIIT) protocols in persons with stroke. Eighteen participants (10 male; 61.9 + 8.3 years of age; 5.8 + 4.2 years poststroke) completed a symptom-limited graded exercise test (GXT) with ECG monitoring to screen for eligibility and determine HR peak. The 3 HIIT protocols involved repeated 30 s bursts of treadmill walking at maximum speed alternated with rest periods of 30 s (P30), 1 min (P60), or 2 min (P120). Sessions were performed in random order and included 5 min warm up, 20 min HIIT, and 5 min cool down. Variables measured included ECG activity, BP, HR, signs and symptoms of cardiovascular intolerance, and orthopedic concerns. Generalized linear mixed models and Tukey-Kramer adjustment were used to compare protocols using p < 0.05. No signs or symptoms of cardiovascular intolerance, significant arrhythmias, ST segment changes, or orthopedic responses resulted in early termination of any HIIT session. HIIT elicited HRs in excess of 88% of measured HR peak including 6 (P30), 8 (P60), and 2 (P120) participants eliciting a HR response above their GXT HR peak . Both maximum BP and HR were significantly higher in P30 and P60 relative to P120. Preliminary data indicate that persons with chronic stroke who have been prescreened with an ECG stress test, a symptom-limited GXT, and a harness for fall protection may safely participate in HIIT, generating substantially higher HRs than what is seen in traditional moderate intensity training.
Fluorescence evolution of leachates during treatment processes from two contrasting landfills.
Sun, W L; Liu, T T; Cui, F; Ni, J R
2008-10-01
Landfill leachates are composed of a complex mixture of organic matter, including a wide range of potentially fluorescent organic compounds. The fluorescence excitation-emission matrix (FEEM) of leachates during treatment processes is investigated. Particular attention is paid to the fluorescence evolution of leachates during treatment processes. Two typical types of landfill, landfill A (a direct municipal solid waste (MSW) landfill) and landfill B (disposal of bottom ashes from MSW incinerators), in a city in Southern China were selected. The results show that two characteristic and intense excitation-emission peaks located at Ex/Em = 310-330 nm/395-410 nm (peak alpha) and Ex/Em = 250-260 nm/450-460 nm (peak alpha') are observed. As the aromatic chemicals, capable of emitting fluorescence, are more recalcitrant to biodegradation than aliphatic chemicals, enhancement of the dissolved organic carbon normalized fluorescence intensities is demonstrated during treatment processes of leachate A and leachate B. This is confirmed by the variation of ultraviolet absorptivity of leachates at 254 nm. Peak alpha' and peak alpha are attributed to a mixture of xenobiotic organic compounds with low molecular weight and relatively stable aromatic fulvic-like matters with high molecular weight, respectively. Humic substances are more resistant to biodegradation than xenobiotic organic compounds, so a significant reduction in the Ialpha'/Ialpha values (fluorescence intensity ratios of peak alpha' and peak a) of leachate A was observed during treatment processes. However, no evident variation for the Ialpha/Ialpha values of leachate B was found during treatment processes owing to the low concentrations of xenobiotic organic compounds in leachate B after incineration.
Hill, Ethan C; Housh, Terry J; Keller, Joshua L; Smith, Cory M; Schmidt, Richard J; Johnson, Glen O
2018-06-22
Low-intensity venous blood flow restriction (vBFR) resistance training has been shown to promote increases in muscle strength and size. Eccentric-only muscle actions are typically a more potent stimulus to increase muscle strength and size than concentric-only muscle actions performed at the same relative intensities. Therefore, the purpose of this investigation was to examine the time-course of changes in muscle strength, hypertrophy, and neuromuscular adaptations following 4 weeks of unilateral forearm flexion low-intensity eccentric vBFR (Ecc-vBFR) vs. low-intensity concentric vBFR (Con-vBFR) resistance training performed at the same relative intensity. Thirty-six women were randomly assigned to either Ecc-vBFR (n = 12), Con-vBFR (n = 12) or control (no intervention, n = 12) group. Ecc-vBFR trained at 30% of eccentric peak torque and Con-vBFR trained at 30% of concentric peak torque. All training and testing procedures were performed at an isokinetic velocity of 120° s - ¹. Muscle strength increased similarly from 0 to 2 and 4 weeks of training as a result of Ecc-vBFR (13.9 and 35.0%) and Con-vBFR (13.4 and 31.2%), but there were no changes in muscle strength for the control group. Muscle thickness increased similarly from 0 to 2 and 4 weeks of training as a result of Ecc-vBFR (11.4 and 12.8%) and Con-vBFR (9.1 and 9.9%), but there were no changes for the control group. In addition, there were no changes in any of the neuromuscular responses. The Ecc-vBFR and Con-vBFR low-intensity training induced comparable increases in muscle strength and size. The increases in muscle strength, however, were not associated with neuromuscular adaptations.
Thermoluminescence of α-Al2O3:C,Mg annealed at 1200 °C
NASA Astrophysics Data System (ADS)
Kalita, J. M.; Chithambo, M. L.
2018-05-01
Stimulated luminescence in α-Al2O3:C,Mg has thus far been studied for samples annealed at temperature no higher than 900 °C as can be seen by an examination of the literature. We report the thermoluminescence (TL) features of α-Al2O3:C,Mg annealed at 1200 °C. A glow curve measured at 1 °C/s from the samples annealed at 1200 °C shows eight peaks at 54, 80, 102, 173, 238, 290, 330 and 387 °C. Kinetic analyses show that the peak at 54 °C follows general order kinetics (b = 1.3) whereas the rest follow first order kinetics. The values of the activation energy of the peaks are between 0.77 eV and 1.90 eV and the frequency factors are of the order of 1010-1014 s-1. The intensity of the peaks at 54, 80, 102 and 173 °C increase with heating rate whereas those of the peaks at 238 and 290 °C decrease with heating rate. The decrease of intensity of the peaks at 238 and 290 °C with heating rate is due to thermal quenching whereas the increase of intensity of the peaks with heating rate indicates an inverse thermal-quenching-like behaviour. Interestingly this behaviour is observed only after annealing at 1200 °C. The activation energy for thermal quenching as calculated using the peaks at 238 and 290 °C are (1.02 ± 0.16) eV and (1.33 ± 0.15) eV respectively. Regarding the dosimetric features, the dose response of the peaks at 54, 80 and 102 °C are sublinear within 1-10 Gy and the peak at 54 °C saturates above 6 Gy. In contrast, the response of the peak at 173 °C is sublinear with 1-4 Gy and superlinear between 4 and 10 Gy. The peaks are found to fade at different rates and the rate of fading is also affected by annealing.
NASA Astrophysics Data System (ADS)
Fazleev, N. G.; Reed, J. A.; Starnes, S. G.; Weiss, A. H.
2011-06-01
The positron annihilation induced Auger spectrum from GaAs(100) displays six As and three Ga Auger peaks below 110 eV corresponding to M4,5VV, M2M4V, M2,3M4,5M4,5 Auger transitions for As and M2,3M4,5M4,5 Auger transitions for Ga. The integrated Auger peak intensities have been used to obtain experimental annihilation probabilities of surface trapped positrons with As 3p and 3d and Ga 3p core level electrons. PAES data is analyzed by performing calculations of positron surface and bulk states and annihilation characteristics of surface trapped positrons with relevant Ga and As core level electrons for both Ga- and As-rich (100) surfaces of GaAs, ideally terminated, non-reconstructed and with (2×8), (2×4), and (4×4) reconstructions. The orientation-dependent variations of the atomic and electron densities associated with reconstructions are found to affect localization of the positron wave function at the surface. Computed positron binding energy, work function, and annihilation characteristics demonstrate their sensitivity both to chemical composition and atomic structure of the topmost layers of the surface. Theoretical annihilation probabilities of surface trapped positrons with As 3d, 3p, and Ga 3p core level electrons are compared with the ones estimated from the measured Auger peak intensities.
Meßler, Carolin Friederike; Holmberg, Hans-Christer; Sperlich, Billy
2018-06-01
To compare the effects of multimodal therapy including supervised high-intensity interval training (HIIT) with those of standard multimodal therapy (TRAD) concerning key variables of physical fitness (peak power and oxygen uptake), motor skills, social behavior, and quality of life in boys with ADHD. A single-center, two-arm randomized, controlled design was used, with 28 boys (8-13 years of age, IQ = 83-136) being randomly assigned to multimodal HIIT (three sessions/week, 4 × 4-min intervals at 95% of peak heart rate) or TRAD. The Movement Assessment Battery for Children II evaluated motor skills and the German version of the hyperkinetic disorder questionnaire for external evaluation by the guardians (FBB-HKS) or German version of the hyperkinetic disorder questionnaire for self-assessment by the children (SBB-HKS) and the KINDL-R questionnaires mental health and health-related quality of life. Both interventions enhanced peak power, and HIIT also reduced submaximal oxygen uptake. HIIT was more effective than TRAD in improving the total score for motor skills (including manual dexterity and ball skills; p < .05), self-esteem, friends, and competence ( p < .05) and, moreover, improved subjective ratings of attention. Three weeks of multimodal therapy including HIIT improved physical fitness, motor skills, certain aspects of quality of life, competence, and attention in boys with ADHD.
GRB physics and cosmology with peak energy-intensity correlations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sawant, Disha, E-mail: sawant@fe.infn.it; University of Nice, 28 Avenue Valrose, Nice 06103; IRAP Erasmus PhD Program, European Union and INAF - IASF Bologna, Via P. Gobetti 101, Bologna 41125
Gamma Ray Bursts (GRBs) are immensely energetic explosions radiating up to 10{sup 54} erg of energy isotropically (E{sub iso}) and they are observed within a wide range of redshift (from ∼ 0.01 up to ∼ 9). Such enormous power and high redshift point at these phenomena being highly favorable to investigate the history and evolution of our universe. The major obstacle in their application as cosmological study-tools is to find a way to standardize the GRBs, for instance similar to SNe Ia. With respect to this goal, the correlation between spectral peak energy (E{sub p,i}) and the “intensity” is amore » positively useful and investigated criterion. Moreover, it has been demonstrated that, through the E{sub p,i} – E{sub iso} correlation, the current data set of GRBs can already contribute to the independent evidence of the matter density Ω{sub M} being ∼ 0.3 for a flat universe scenario. We try to inspect and compare the correlations of E{sub p,i} with different intensity indicators (e.g., radiated energy, average and peak luminosity, bolometric vs. monochromatic quantities, etc.) both in terms of intrinsic dispersion and precise estimation of Ω{sub M}. The outcome of such studies are further analyzed in verifying the reliability of the correlations for both GRB physics and their standardization for cosmology.« less
Laser pulse heating of steel mixing with WC particles in a irradiated region
NASA Astrophysics Data System (ADS)
Shuja, S. Z.; Yilbas, B. S.; Ali, H.; Karatas, C.
2016-12-01
Laser pulse heating of steel mixing with tungsten carbide (WC) particles is carried out. Temperature field in the irradiated region is simulated in line with the experimental conditions. In the analysis, a laser pulse parameter is introduced, which defines the laser pulse intensity distribution at the irradiated surface. The influence of the laser parameter on the melt pool size and the maximum temperature increase in the irradiated region is examined. Surface temperature predictions are compared with the experimental data. In addition, the distribution of WC particles and their re-locations in the treated layer, due to combination of the natural convection and Marangoni currents, are predicted. The findings are compared to the experimental data. It is found that surface temperature predictions agree well with the experimental data. The dislocated WC particles form a streamlining in the near region of the melt pool wall, which agree with the experimental findings. The Gaussian distribution of the laser pulse intensity results in the maximum peak temperature and the maximum flow velocity inside the melt pool. In this case, the melt pool depth becomes the largest as compared to those corresponding to other laser pulse intensity distributions at the irradiated surface.
Structure of sunspot light bridges in the chromosphere and transition region
NASA Astrophysics Data System (ADS)
Rezaei, R.
2018-01-01
Context. Light bridges (LBs) are elongated structures with enhanced intensity embedded in sunspot umbra and pores. Aims: We studied the properties of a sample of 60 LBs observed with the Interface Region Imaging Spectrograph (IRIS). Methods: Using IRIS near- and far-ultraviolet spectra, we measured the line intensity, width, and Doppler shift; followed traces of LBs in the chromosphere and transition region (TR); and compared LB parameters with umbra and quiet Sun. Results: There is a systematic emission enhancement in LBs compared to nearby umbra from the photosphere up to the TR. Light bridges are systematically displaced toward the solar limb at higher layers: the amount of the displacement at one solar radius compares well with the typical height of the chromosphere and TR. The intensity of the LB sample compared to the umbra sample peaks at the middle/upper chromosphere where they are almost permanently bright. Spectral lines emerging from the LBs are broader than the nearby umbra. The systematic redshift of the Si IV line in the LB sample is reduced compared to the quiet Sun sample. We found a significant correlation between the line width of ions arising at temperatures from 3 × 104 to 1.5 × 105 K as there is also a strong spatial correlation among the line and continuum intensities. In addition, the intensity-line width relation holds for all spectral lines in this study. The correlations indicate that the cool and hot plasma in LBs are coupled. Conclusions: Light bridges comprise multi-temperature and multi-disciplinary structures extending up to the TR. Diverse heating sources supply the energy and momentum to different layers, resulting in distinct dynamics in the photosphere, chromosphere, and TR.
Effect of water-based recovery on blood lactate removal after high-intensity exercise.
Lucertini, Francesco; Gervasi, Marco; D'Amen, Giancarlo; Sisti, Davide; Rocchi, Marco Bruno Luigi; Stocchi, Vilberto; Benelli, Piero
2017-01-01
This study assessed the effectiveness of water immersion to the shoulders in enhancing blood lactate removal during active and passive recovery after short-duration high-intensity exercise. Seventeen cyclists underwent active water- and land-based recoveries and passive water and land-based recoveries. The recovery conditions lasted 31 minutes each and started after the identification of each cyclist's blood lactate accumulation peak, induced by a 30-second all-out sprint on a cycle ergometer. Active recoveries were performed on a cycle ergometer at 70% of the oxygen consumption corresponding to the lactate threshold (the control for the intensity was oxygen consumption), while passive recoveries were performed with subjects at rest and seated on the cycle ergometer. Blood lactate concentration was measured 8 times during each recovery condition and lactate clearance was modeled over a negative exponential function using non-linear regression. Actual active recovery intensity was compared to the target intensity (one sample t-test) and passive recovery intensities were compared between environments (paired sample t-tests). Non-linear regression parameters (coefficients of the exponential decay of lactate; predicted resting lactates; predicted delta decreases in lactate) were compared between environments (linear mixed model analyses for repeated measures) separately for the active and passive recovery modes. Active recovery intensities did not differ significantly from the target oxygen consumption, whereas passive recovery resulted in a slightly lower oxygen consumption when performed while immersed in water rather than on land. The exponential decay of blood lactate was not significantly different in water- or land-based recoveries in either active or passive recovery conditions. In conclusion, water immersion at 29°C would not appear to be an effective practice for improving post-exercise lactate removal in either the active or passive recovery modes.
De Strijcker, Dorien; Lapauw, Bruno; Ouwens, D Margriet; Van de Velde, Dominique; Hansen, Dominique; Petrovic, Mirko; Cuvelier, Claude; Tonoli, Cajsa; Calders, Patrick
2018-06-01
To evaluate the effect of high intensity training (HIT) on physical fitness, basal respiratory exchange ratio (bRER), insulin sensitivity and muscle histology in overweight/obese men compared to continuous aerobic training (CAT). 16 male participants with overweight/obesity (age: 42-57 years, body mass index: 28-36 kg/m2) were randomized to HIT (n=8) or CAT (n=8) for 10 weeks, twice a week. HIT was composed of 10 minutes high intensity, 10 minutes continuous aerobic, 10 minutes high intensity exercises. CAT was composed of three times 10 minutes continuous exercising. Changes in anthropometry, physical and metabolic fitness were evaluated. Muscle histology (mitochondria and lipid content) was evaluated by transmission electron microscopy (TEM). HIT showed a significant increase for peak VO2 (P=0.01), for insulin sensitivity (AUC glucose (P<0,001), AUC insulin (P<0,001), OGTT composite score (P=0.007)) and a significant decrease of bRER (P<0.001) compared to CAT. Muscle mitochondrial content was significantly increased after HIT at the subsarcolemmal (P=0.004 number and P=0.001 surface) as well as the intermyofibrillar site (P<0.001 number and P=0.001 surface). High intensity training elicits stronger beneficial effects on physical fitness, basal RER, insulin sensitivity, and muscle mitochondrial content, as compared to continuous aerobic training.
Peak broadening and peak shift pole figures investigations by STRESS-SPEC diffractometer at FRM II
NASA Astrophysics Data System (ADS)
Gan, W. M.; Randau, C.; Hofmann, M.; Brokmeier, H. G.; Mueller, M.; Schreyer, A.
2012-02-01
This paper studied for the first time peak intensity, peak position and FHWM pole figures with one time measurement at the neutron diffractometer STRESS-SPEC via in-situ tensile deformation on austenitic steel. Fibre distribution with its evolution from central tensile direction to normal direction of these three kinds of pole figures was obtained. Variation of peak position and FWHM can be correlated to the reorientation of the texture component.
Comparison of sympathetic nerve responses to neck and forearm isometric exercise
NASA Technical Reports Server (NTRS)
Steele, S. L. Jr; Ray, C. A.
2000-01-01
PURPOSE: Although the autonomic and cardiovascular responses to arm and leg exercise have been studied, the sympathetic adjustments to exercise of the neck have not. The purpose of the present study was twofold: 1) to determine sympathetic and cardiovascular responses to isometric contractions of the neck extensors and 2) to compare sympathetic and cardiovascular responses to isometric exercise of the neck and forearm. METHODS: Muscle sympathetic nerve activity (MSNA), mean arterial pressure (MAP), and heart rate were measured in nine healthy subjects while performing isometric neck extension (INE) and isometric handgrip (IHG) in the prone position. After a 3-min baseline period, subjects performed three intensities of INE for 2.5 min each: 1) unloaded (supporting head alone), 2) 10% maximal voluntary contraction (MVC), and 3) 30% MVC, then subjects performed two intensities (10% and 30% MVC) of IHG for 2.5 min. RESULTS: Supporting the head by itself did not significantly change any of the variables. During [NE, MAP significantly increased by 10 +/- 2 and 31 +/- 4 mm Hg and MSNA increased by 67 +/- 46 and 168 +/- 36 units/30 s for 10% and 30% MVC, respectively. IHG and INE evoked similar responses at 10% MVC, but IHG elicited higher peak MAP and MSNA at 30% MVC (37 +/- 7 mm Hg (P < 0.05) and 300 +/- 48 units/30 s (P < 0.01) for IHG, respectively). CONCLUSIONS: The data indicate that INE can elicit marked increases in MSNA and cardiovascular responses but that it evokes lower peak responses as compared to IHG. We speculate that possible differences in muscle fiber type composition, muscle mass, and/or muscle architecture of the neck and forearm are responsible for these differences in peak responses.
Benda, Nathalie M M; Seeger, Joost P H; Stevens, Guus G C F; Hijmans-Kersten, Bregina T P; van Dijk, Arie P J; Bellersen, Louise; Lamfers, Evert J P; Hopman, Maria T E; Thijssen, Dick H J
2015-01-01
Physical fitness is an important prognostic factor in heart failure (HF). To improve fitness, different types of exercise have been explored, with recent focus on high-intensity interval training (HIT). We comprehensively compared effects of HIT versus continuous training (CT) in HF patients NYHA II-III on physical fitness, cardiovascular function and structure, and quality of life, and hypothesize that HIT leads to superior improvements compared to CT. Twenty HF patients (male:female 19:1, 64±8 yrs, ejection fraction 38±6%) were allocated to 12-weeks of HIT (10*1-minute at 90% maximal workload-alternated by 2.5 minutes at 30% maximal workload) or CT (30 minutes at 60-75% of maximal workload). Before and after intervention, we examined physical fitness (incremental cycling test), cardiac function and structure (echocardiography), vascular function and structure (ultrasound) and quality of life (SF-36, Minnesota living with HF questionnaire (MLHFQ)). Training improved maximal workload, peak oxygen uptake (VO2peak) related to the predicted VO2peak, oxygen uptake at the anaerobic threshold, and maximal oxygen pulse (all P<0.05), whilst no differences were present between HIT and CT (N.S.). We found no major changes in resting cardiovascular function and structure. SF-36 physical function score improved after training (P<0.05), whilst SF-36 total score and MLHFQ did not change after training (N.S.). Training induced significant improvements in parameters of physical fitness, although no evidence for superiority of HIT over CT was demonstrated. No major effect of training was found on cardiovascular structure and function or quality of life in HF patients NYHA II-III. Nederlands Trial Register NTR3671.
Xanthos, Paul D; Gordon, Brett A; Kingsley, Michael I C
2017-03-01
Resistance training has demonstrated efficacy in cardiac rehabilitation programs, but the optimal prescription of resistance training is unknown. This systematic review with meta-analysis compared the effectiveness of cardiac rehabilitation consisting of resistance training either alone (RT) or in combination with aerobic training (CT) with aerobic training only (AT) on outcomes of physical function. Further, resistance training intensity and intervention duration were examined to identify if these factors moderate efficacy. Six electronic databases were searched to identify studies investigating RT, coronary heart disease and physical function. The overall quality of evidence was assessed using the GRADE approach. Meta-analyses were performed when possible and qualitative analysis was performed for the remaining data. Improvements in peak oxygen uptake (WMD: 0.61, 95% CI: 0.20-1.10), peak work capacity (SMD: 0.38, 95% CI: 0.11-0.64) and muscular strength (SMD: 0.65, 95% CI: 0.43-0.87) significantly favoured CT over AT with moderate quality evidence. There was no evidence of a difference in effect when comparing RT and AT. Shorter duration CT was superior to shorter duration AT for improving peak oxygen uptake and muscular strength (low quality evidence) while longer duration CT was only superior to longer duration AT in improving muscular strength (moderate quality evidence). CT is more beneficial than AT alone for improving physical function. Although preliminary findings are promising, more high-quality evidence is required to determine the efficacy of high intensity resistance training. Shorter duration interventions that include resistance training might allow patients to return to their normal activities of daily living earlier. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Davidson, Ross; Elliott, Stacy; Krassioukov, Andrei
2016-12-15
Sexuality is an integral part of the human experience and persists in health and disability. The cardiovascular system is crucial to sexual function and can be affected profoundly by spinal cord injury (SCI). The effects of sexual activity on the cardiovascular system in SCI have not been summarized and compared with sexual activity in able-bodied individuals. A keyword search of Embase, PubMed, and Medline was conducted. From 471 retrieved studies for able-bodied individuals, 11 were included that met the strict criteria of medically uncomplicated participants. In the SCI literature, 117 studies were screened, with 18 meeting criteria. In able-bodied persons, sexual activity resulted in modest increases in systolic blood pressure peaking at orgasm (males of 163 mm Hg and females of 142 mm Hg) and returning to baseline shortly afterward. In persons with SCI, results varied from minimal changes to significant elevations in systolic blood pressure because of episodes of autonomic dysreflexia, especially in those with high thoracic and cervical lesions. Peak systolic blood pressure in these individuals was measured to be as high as 325 mm Hg. In the SCI population, more intense stimuli (including penile vibrostimulation and electroejaculation) tended to result in a greater increase in systolic blood pressure compared with self-stimulation. Studies that used continuous versus intermittent monitoring were more likely to report greater changes in systolic blood pressure. In able-bodied persons, sexual activity results in modest increases in blood pressure. In those with SCI, intense stimulation and higher injury levels result in a higher likelihood of autonomic dysreflexia and elevated blood pressure. Because of rapid changes in blood pressure, continuous monitoring is more advantageous than intermittent measurement, because the latter may miss peak values.
Spectral Ripple Discrimination in Normal-Hearing Infants.
Horn, David L; Won, Jong Ho; Rubinstein, Jay T; Werner, Lynne A
Spectral resolution is a correlate of open-set speech understanding in postlingually deaf adults and prelingually deaf children who use cochlear implants (CIs). To apply measures of spectral resolution to assess device efficacy in younger CI users, it is necessary to understand how spectral resolution develops in normal-hearing children. In this study, spectral ripple discrimination (SRD) was used to measure listeners' sensitivity to a shift in phase of the spectral envelope of a broadband noise. Both resolution of peak to peak location (frequency resolution) and peak to trough intensity (across-channel intensity resolution) are required for SRD. SRD was measured as the highest ripple density (in ripples per octave) for which a listener could discriminate a 90° shift in phase of the sinusoidally-modulated amplitude spectrum. A 2 × 3 between-subjects design was used to assess the effects of age (7-month-old infants versus adults) and ripple peak/trough "depth" (10, 13, and 20 dB) on SRD in normal-hearing listeners (experiment 1). In experiment 2, SRD thresholds in the same age groups were compared using a task in which ripple starting phases were randomized across trials to obscure within-channel intensity cues. In experiment 3, the randomized starting phase method was used to measure SRD as a function of age (3-month-old infants, 7-month-old infants, and young adults) and ripple depth (10 and 20 dB in repeated measures design). In experiment 1, there was a significant interaction between age and ripple depth. The infant SRDs were significantly poorer than the adult SRDs at 10 and 13 dB ripple depths but adult-like at 20 dB depth. This result is consistent with immature across-channel intensity resolution. In contrast, the trajectory of SRD as a function of depth was steeper for infants than adults suggesting that frequency resolution was better in infants than adults. However, in experiment 2 infant performance was significantly poorer than adults at 20 dB depth suggesting that variability of infants' use of within-channel intensity cues, rather than better frequency resolution, explained the results of experiment 1. In experiment 3, age effects were seen with both groups of infants showing poorer SRD than adults but, unlike experiment 1, no significant interaction between age and depth was seen. Measurement of SRD thresholds in individual 3 to 7-month-old infants is feasible. Performance of normal-hearing infants on SRD may be limited by across-channel intensity resolution despite mature frequency resolution. These findings have significant implications for design and stimulus choice for applying SRD for testing infants with CIs. The high degree of variability in infant SRD can be somewhat reduced by obscuring within-channel cues.
Spectral Ripple Discrimination in Normal Hearing Infants
Horn, David L.; Won, Jong Ho; Rubinstein, Jay T.; Werner, Lynne A.
2016-01-01
Objectives Spectral resolution is a correlate of open-set speech understanding in post-lingually deaf adults as well as pre-lingually deaf children who use cochlear implants (CIs). In order to apply measures of spectral resolution to assess device efficacy in younger CI users, it is necessary to understand how spectral resolution develops in NH children. In this study, spectral ripple discrimination (SRD) was used to measure listeners’ sensitivity to a shift in phase of the spectral envelope of a broadband noise. Both resolution of peak to peak location (frequency resolution) and peak to trough intensity (across-channel intensity resolution) are required for SRD. Design SRD was measured as the highest ripple density (in ripples per octave) for which a listener could discriminate a 90 degree shift in phase of the sinusoidally-modulated amplitude spectrum. A 2X3 between subjects design was used to assess the effects of age (7-month-old infants versus adults) and ripple peak/trough “depth” (10, 13, and 20 dB) on SRD in normal hearing listeners (Experiment 1). In Experiment 2, SRD thresholds in the same age groups were compared using a task in which ripple starting phases were randomized across trials to obscure within-channel intensity cues. In Experiment 3, the randomized starting phase method was used to measure SRD as a function of age (3-month-old infants, 7-month-old infants, and young adults) and ripple depth (10 and 20 dB in repeated measures design). Results In Experiment 1, there was a significant interaction between age and ripple depth. The Infant SRDs were significantly poorer than the adult SRDs at 10 and 13 dB ripple depths but adult-like at 20 dB depth. This result is consistent with immature across-channel intensity resolution. In contrast, the trajectory of SRD as a function of depth was steeper for infants than adults suggesting that frequency resolution was better in infants than adults. However, in Experiment 2 infant performance was significantly poorer than adults at 20 dB depth suggesting that variability of infants’ use of within-channel intensity cues, rather than better frequency resolution, explained the results of Experiment 1. In Experiment 3, age effects were seen with both groups of infants showing poorer SRD than adults but, unlike Experiment 1, no significant interaction between age and depth was seen. Conclusions Measurement of SRD thresholds in individual 3 to 7-month-old infants is feasible. Performance of NH infants on SRD may be limited by across-channel intensity resolution despite mature frequency resolution. These findings have significant implications for design and stimulus choice for applying SRD for testing infants with CIs. The high degree of variability in infant SRD can be somewhat reduced by obscuring within-channel cues. PMID:27768611
How we remember the emotional intensity of past musical experiences
Schäfer, Thomas; Zimmermann, Doreen; Sedlmeier, Peter
2014-01-01
Listening to music usually elicits emotions that can vary considerably in their intensity over the course of listening. Yet, after listening to a piece of music, people are easily able to evaluate the music's overall emotional intensity. There are two different hypotheses about how affective experiences are temporally processed and integrated: (1) all moments' intensities are integrated, resulting in an averaged value; (2) the overall evaluation is built from specific single moments, such as the moments of highest emotional intensity (peaks), the end, or a combination of these. Here we investigated what listeners do when building an overall evaluation of a musical experience. Participants listened to unknown songs and provided moment-to-moment ratings of experienced intensity of emotions. Subsequently, they evaluated the overall emotional intensity of each song. Results indicate that participants' evaluations were predominantly influenced by their average impression but that, in addition, the peaks and end emotional intensities contributed substantially. These results indicate that both types of processes play a role: All moments are integrated into an averaged value but single moments might be assigned a higher value in the calculation of this average. PMID:25177311
Rate modulation of human anconeus motor units during high-intensity dynamic elbow extensions.
Cowling, Brianna L; Harwood, Brad; Copithorne, David B; Rice, Charles L
2016-08-01
Investigations of high-intensity isometric fatiguing protocols report decreases in motor unit firing rates (MUFRs), but little is known regarding changes in MUFRs following fatigue induced by high-intensity dynamic contractions. Our purpose was to evaluate MUFRs of the anconeus (an accessory elbow extensor) and elbow extension power production as a function of time to task failure (TTF) during high-velocity fatiguing concentric contractions against a moderately heavy resistance. Fine-wire intramuscular electrode pairs were inserted into the anconeus to record MUs in 12 male participants (25 ± 3 yr), over repeated sessions on separate days. MUs were tracked throughout a three-stage, varying load dynamic elbow extension protocol designed to extend the task duration for >1 min thereby inducing substantial fatigue. Mean MUFRs and peak power were calculated for three relative time ranges: 0-15% TTF (beginning), 45-60% TTF (middle) and 85-100% TTF (end). Mean duration of the overall fatigue protocol was ∼80 s. Following the protocol, isometric maximum voluntary contraction (MVC), highest velocity at 35% MVC load, and peak power decreased 37, 60, and 64% compared with baseline, respectively. Data from 20 anconeus MUs tracked successfully throughout the protocol indicated a reduction in MUFRs in relation to power loss from 36 Hz/160 W (0-15% TTF) to 28 Hz/97 W (45-60% TTF) to 23 Hz/43 W (85-100% TTF). During these high-intensity maximal effort concentric contractions, anconeus MUFRs decreased substantially (>35%). Although the absolute MUFRs were higher in the present study than those reported previously for other muscles during sustained high-intensity isometric tasks, the relative decrease in MUFRs was similar between the two tasks. Copyright © 2016 the American Physiological Society.
Peak intensity measurement of relativistic lasers via nonlinear Thomson scattering.
Har-Shemesh, Omri; Di Piazza, Antonino
2012-04-15
The measurement of peak laser intensities exceeding 10(20) W/cm(2) is in general a very challenging task. We suggest a simple method to accurately measure such high intensities up to about 10(23) W/cm(2), by colliding a beam of ultrarelativistic electrons with the laser pulse. The method exploits the high directionality of the radiation emitted by ultrarelativistic electrons via nonlinear Thomson scattering. Initial electron energies well within the reach of laser wake-field accelerators are required, allowing in principle for an all-optical setup. Accuracies of the order of 10% are theoretically envisaged. © 2012 Optical Society of America
NASA Astrophysics Data System (ADS)
Ulanov, S. F.
1990-06-01
A method proposed for investigating the statistics of bulk optical breakdown relies on multifrequency lasers, which eliminates the influence of the laser radiation intensity statistics. The method is based on preliminary recording of the peak intensity statistics of multifrequency laser radiation pulses at the caustic using the optical breakdown threshold of K8 glass. The probability density distribution function was obtained at the focus for the peak intensities of the radiation pulses of a multifrequency laser. This method may be used to study the self-interaction under conditions of bulk optical breakdown of transparent dielectrics.
Wang, Shijin; Li, Cunfang; Yang, Lizhu
2018-06-26
The decoupling effect between economic growth and energy structure was quantitatively analyzed from 1999 to 2014 across China. The results showed it existed weak decoupling effects in most regions. Based on the analysis of the influence of energy structure on carbon intensity, using scenario simulation methods and Markov chain modeling, the carbon intensity was predicted for China in 2020. The impact of energy structure adjustment on the carbon intensity to meet China's carbon target by 18 possible scenarios are calculated. Furthermore, the peak value of carbon emissions was also calculated in 2030. The results showed that the carbon intensity predicted for China in 2020 can be achieved regardless of whether the energy structure was adjusted or not when energy saving and carbon reduction policies maintained with economic growth at 6-7%. Moreover, given fixed energy structure growth, for each 1% of economic growth, the carbon intensity will decrease by about 3.5%. Given fixed economic growth, the decrease of energy intensity will be greater if the control of energy consumption is stronger. The effect of energy structure adjustment on the decreasing of carbon intensity will be 4% higher under constraints than without constraints. On average, the contribution of energy structure adjustment to achieving the carbon intensity target was calculated as 4% higher than that with constraints. In addition, given relatively fixed economic growth at 6-7%, the peak value of carbon emission in 2030 was calculated as 13.209 billion tons with constraints and 14.38 billion tons without constraints.
Spainhour, John Christian G; Janech, Michael G; Schwacke, John H; Velez, Juan Carlos Q; Ramakrishnan, Viswanathan
2014-01-01
Matrix assisted laser desorption/ionization time-of-flight (MALDI-TOF) coupled with stable isotope standards (SIS) has been used to quantify native peptides. This peptide quantification by MALDI-TOF approach has difficulties quantifying samples containing peptides with ion currents in overlapping spectra. In these overlapping spectra the currents sum together, which modify the peak heights and make normal SIS estimation problematic. An approach using Gaussian mixtures based on known physical constants to model the isotopic cluster of a known compound is proposed here. The characteristics of this approach are examined for single and overlapping compounds. The approach is compared to two commonly used SIS quantification methods for single compound, namely Peak Intensity method and Riemann sum area under the curve (AUC) method. For studying the characteristics of the Gaussian mixture method, Angiotensin II, Angiotensin-2-10, and Angiotenisn-1-9 and their associated SIS peptides were used. The findings suggest, Gaussian mixture method has similar characteristics as the two methods compared for estimating the quantity of isolated isotopic clusters for single compounds. All three methods were tested using MALDI-TOF mass spectra collected for peptides of the renin-angiotensin system. The Gaussian mixture method accurately estimated the native to labeled ratio of several isolated angiotensin peptides (5.2% error in ratio estimation) with similar estimation errors to those calculated using peak intensity and Riemann sum AUC methods (5.9% and 7.7%, respectively). For overlapping angiotensin peptides, (where the other two methods are not applicable) the estimation error of the Gaussian mixture was 6.8%, which is within the acceptable range. In summary, for single compounds the Gaussian mixture method is equivalent or marginally superior compared to the existing methods of peptide quantification and is capable of quantifying overlapping (convolved) peptides within the acceptable margin of error.
Kilian, Yvonne; Engel, Florian; Wahl, Patrick; Achtzehn, Silvia; Sperlich, Billy; Mester, Joachim
2016-12-01
The aim of the present study was to compare the effects of high-intensity interval training (HIIT) vs high-volume training (HVT) on salivary stress markers [cortisol (sC), testosterone (sT), alpha-amylase (sAA)], metabolic and cardiorespiratory response in young athletes. Twelve young male cyclists (14 ± 1 years; 57.9 ± 9.4 mL min -1 kg -1 peak oxygen uptake) performed one session of HIIT (4 × 4 min intervals at 90-95 % peak power output separated by 3 min of active rest) and one session of HVT (90 min constant load at 60 % peak power output). The levels of sC, sT, their ratio (sT/sC) and sAA were determined before and 0, 30, 60, 180 min after each intervention. Metabolic and cardiorespiratory stress was characterized by blood lactate, blood pH, respiratory exchange ratio (RER) and heart rate (HR), oxygen uptake ([Formula: see text]), ventilation (V E ) and ventilatory equivalent (V E /[Formula: see text]). sC increased 30 and 60 min after HIIT. However, 180 min post exercise, sC decreased below baseline levels in both conditions. sT increased 0 and 30 min after HIIT and 0 min after HVT. sAA and sT/sC ratio did not change significantly over time in HIIT nor HVT. Metabolic and cardiorespiratory stress, evidenced by blood lactate, HR, [Formula: see text], V E , and V E /[Formula: see text] was higher during HIIT compared to HVT. The metabolic and cardiorespiratory stress during HIIT was higher compared to HVT, but based on salivary analyses (cortisol, testosterone, alpha-amylase), we conclude no strong acute catabolic effects neither by HIIT nor by HVT.
Differential identification of mushrooms sclerotia by IR macro-fingerprint method
NASA Astrophysics Data System (ADS)
Choong, Yew Keong; Lan, Jin; Lee, Han Lim; Chen, Xiang-dong; Wang, Xiao-guang; Yang, Yu-ping
2016-01-01
Many macrofungus sclerotia are well-known medicinal herbs, health food and nutritional supplements. However, the prevalent adulterant commercial products are major hindrances to their incorporation into mainstream medical use in many countries. The mushroom sclerotia of Lignosus rhinocerotis, Poria cocos, Polyporus umbellatus, Pleurotus tuber-regium and Omphalia lapidescens are commonly used in traditional Chinese medicine. In this study, IR macro-fingerprint method was used in the identification of these sclerotia. The results showed that the spectrum of L. rhinocerotis (LR) was comparable with P. cocos with 94.4% correlation, except that the peak at 1543 cm-1 of LR appeared in lower intensity. The spectrum of P. umbellatus and P. tuber-regium was also correlated (91.5%), as both spectra could be clearly discriminated in that P. umbellatus spectrum has small base peaks located at the range of 1680-1500 cm-1. O. lapidescens was not comparable with all the other sclerotia as its spectrum was totally different. Its base peak was broad and derivated equally along the range. The first IR has revealed the dissimilarity among five mushrooms sclerotia. The second derivative and 2DIR further enhanced the identification in detail.
Sato, Gosuke; Osumi, Michihiro; Morioka, Shu
2017-01-31
To investigate the effects of wheelchair propulsion on neuropathic pain and to examine resting electroencephalography pre- and post-wheelchair propulsion after spinal cord injury. Cross-sectional study. Eleven individuals with spinal cord injury and pain and 10 healthy controls. Single-session 15-min wheelchair propulsion and measurement of resting electroence-phalography. Effects of wheelchair propulsion were investigated using numerical rating scale (NRS) for neuropathic pain and short-form Profile of Mood States-Brief for mood. Peak alpha frequency on electroencephalography was calculated in 4 regions of interest; frontal, central, parietal and occipital areas. These outcomes were compared between pre- and post-wheelchair propulsion. Ten participants with spinal cord injury and all healthy controls completed the wheelchair propulsion exercise. NRS scores and negative mood were significantly improved following the wheelchair propulsion exercise. Pre-wheelchair propulsion, parietal and occipital peak alpha frequencies were significantly lower in the spinal cord injury group compared with the healthy controls group. Post-wheelchair propulsion, central peak alpha frequency increased in the spinal cord injury group. Wheelchair propulsion exercise temporarily decreased neuropathic pain intensity, improved negative mood, and modified alpha activity in spinal cord injury.
Differential identification of mushrooms sclerotia by IR macro-fingerprint method.
Choong, Yew Keong; Lan, Jin; Lee, Han Lim; Chen, Xiang-Dong; Wang, Xiao-Guang; Yang, Yu-Ping
2016-01-05
Many macrofungus sclerotia are well-known medicinal herbs, health food and nutritional supplements. However, the prevalent adulterant commercial products are major hindrances to their incorporation into mainstream medical use in many countries. The mushroom sclerotia of Lignosus rhinocerotis, Poria cocos, Polyporus umbellatus, Pleurotus tuber-regium and Omphalia lapidescens are commonly used in traditional Chinese medicine. In this study, IR macro-fingerprint method was used in the identification of these sclerotia. The results showed that the spectrum of L. rhinocerotis (LR) was comparable with P. cocos with 94.4% correlation, except that the peak at 1543cm(-1) of LR appeared in lower intensity. The spectrum of P. umbellatus and P. tuber-regium was also correlated (91.5%), as both spectra could be clearly discriminated in that P. umbellatus spectrum has small base peaks located at the range of 1680-1500cm(-1). O. lapidescens was not comparable with all the other sclerotia as its spectrum was totally different. Its base peak was broad and derivated equally along the range. The first IR has revealed the dissimilarity among five mushrooms sclerotia. The second derivative and 2DIR further enhanced the identification in detail. Copyright © 2015 Elsevier B.V. All rights reserved.
2D Raman band splitting in graphene: Charge screening and lifting of the K-point Kohn anomaly.
Wang, Xuanye; Christopher, Jason W; Swan, Anna K
2017-10-19
Pristine graphene encapsulated in hexagonal boron nitride has transport properties rivalling suspended graphene, while being protected from contamination and mechanical damage. For high quality devices, it is important to avoid and monitor accidental doping and charge fluctuations. The 2D Raman double peak in intrinsic graphene can be used to optically determine charge density, with decreasing peak split corresponding to increasing charge density. We find strong correlations between the 2D 1 and 2D 2 split vs 2D line widths, intensities, and peak positions. Charge density fluctuations can be measured with orders of magnitude higher precision than previously accomplished using the G-band shift with charge. The two 2D intrinsic peaks can be associated with the "inner" and "outer" Raman scattering processes, with the counterintuitive assignment of the phonon closer to the K point in the KM direction (outer process) as the higher energy peak. Even low charge screening lifts the phonon Kohn anomaly near the K point for graphene encapsulated in hBN, and shifts the dominant intensity from the lower to the higher energy peak.
Evaluating intervention fidelity: an example from a high-intensity interval training study.
Taylor, Kathryn L; Weston, Matthew; Batterham, Alan M
2015-01-01
Intervention fidelity refers to the degree to which an experimental manipulation has been implemented as intended, but simple, robust methods for quantifying fidelity have not been well documented. Therefore, we aim to illustrate a rigorous quantitative evaluation of intervention fidelity, using data collected during a high-intensity interval training intervention. Single-group measurement study. Seventeen adolescents (mean age ± standard deviation [SD] 14.0 ± 0.3 years) attended a 10-week high-intensity interval training intervention, comprising two exercise sessions per week. Sessions consisted of 4-7 45-s maximal effort repetitions, interspersed with 90-s rest. We collected heart rate data at 5-s intervals and recorded the peak heart rate for each repetition. The high-intensity exercise criterion was ≥ 90% of individual maximal heart rate. For each participant, we calculated the proportion of total exercise repetitions exceeding this threshold. A linear mixed model was applied to properly separate the variability in peak heart rate between- and within-subjects. Results are presented both as intention to treat (including missed sessions) and per protocol (only participants with 100% attendance; n=8). For intention to treat, the median (interquartile range) proportion of repetitions meeting the high-intensity criterion was 58% (42% to 68%). The mean peak heart rate was 85% of maximal, with a between-subject SD of 7.8 (95% confidence interval 5.4 to 11.3) percentage points and a within-subject SD of 15.1 (14.6 to 15.6) percentage points. For the per protocol analysis, the median proportion of high-intensity repetitions was 68% (47% to 86%). The mean peak heart rate was 91% of maximal, with between- and within-subject SDs of 3.1 (-1.3 to 4.6) and 3.4 (3.2 to 3.6) percentage points, respectively. Synthesising information on exercise session attendance and compliance (exercise intensity) quantifies the intervention dose and informs evaluations of treatment fidelity.
Xie, Fang; Li, Zhi-Ping; Wang, Hong-Wei; Fei, Xiang; Jiao, Zi-Yu; Tang, Wen-Bo; Tang, Jie; Luo, Yu-Kun
2016-01-01
To assess the feasibility of ultrasound molecular imaging in the early diagnosis of liver ischemia-reperfusion injury (IRI) using a nanoscale contrast agent targeting anti-intracellular adhesion molecule-1 (anti-ICAM-1). The targeted nanobubbles containing anti-ICAM-1 antibody were prepared using the avidin-biotin binding method. Human hepatic sinusoidal endothelial cells (HHSECs) were cultured at the circumstances of hypoxia/reoxygenation (H/R) and low temperature. The rabbit liver IRI model (I/R group) was established using the Pringle's maneuver. The time-intensity curve of the liver contrast ultrasonographic images was plotted and the peak intensity, time to peak, and time of duration were calculated. The size of the targeted nanobubbles were 148.15 ± 39.75 nm and the concentration was 3.6-7.4 × 109/ml, and bound well with the H/R HHSECs. Animal contrast enhanced ultrasound images showed that the peak intensity and time of duration of the targeted nanobubbles were significantly higher than that of common nanobubbles in the I/R group, and the peak intensity and time of duration of the targeted nanobubbles in the I/R group were also significantly higher than that in the SO group. The targeted nanobubbles have small particle size, stable characteristic, and good targeting ability, which can assess hepatic ischemia-reperfusion injury specifically, noninvasively, and quantitatively at the molecular level.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zinin, Pavel; Tatsumi-Petrochilos, Lisa; Bonal, Lydie
2015-10-15
A systematic study of the Raman spectra of the titanomagnetite solid-solution series (Fe{sub 3-x}Ti{sub x}O{sub 4}) for x = {approx}0.0, 0.2, 0.4, and 0.6 has been conducted. The samples showed combinations of five previously predicted Raman peaks at {approx}190, 310, 460, 540, and 670 cm{sup -1} that correspond to vibrational modes with T{sub 2g}(1), E{sub g}, T{sub 2g}(3), T{sub 2g}(2), and A{sub 1g}, respectively. The calibration of Raman spectra for titanomagnetite with known values of Ti concentrations reveals a strong dependence of relative intensity for the T{sub 2g}(2) and T{sub 2g}(3) modes on Ti concentration. The most prominent feature ismore » the appearance and increase in the relative intensity of a T{sub 2g}(3) peak above x = {approx}0.2. On the other hand, the Raman peak for the T{sub 2g}(2) mode gradually diminishes as Ti increases and nearly disappears at x = {approx}0.6. Combining the two relative intensities potentially provides a sensitive indicator of Ti content. The technique was applied to study titanomagnetite in grains from Hana Volcanics and melatroctolite from Rhode Island.« less
NASA Technical Reports Server (NTRS)
Gray, R. B.; Pierce, G. A.
1972-01-01
Wind tunnel tests were performed on two oscillating two-dimensional lifting surfaces. The first of these models had an NACA 0012 airfoil section while the second simulated the classical flat plate. Both of these models had a mean angle of attack of 12 degrees while being oscillated in pitch about their midchord with a double amplitude of 6 degrees. Wake surveys of sound pressure level were made over a frequency range from 16 to 32 Hz and at various free stream velocities up to 100 ft/sec. The sound pressure level spectrum indicated significant peaks in sound intensity at the oscillation frequency and its first harmonic near the wake of both models. From a comparison of these data with that of a sound level meter, it is concluded that most of the sound intensity is contained within these peaks and no appreciable peaks occur at higher harmonics. It is concluded that within the wake the sound intensity is largely pseudosound while at one chord length outside the wake, it is largely true vortex sound. For both the airfoil and flat plate the peaks appear to be more strongly dependent upon the airspeed than on the oscillation frequency. Therefore reduced frequency does not appear to be a significant parameter in the generation of wake sound intensity.
Blood flow regulation and oxygen uptake during high-intensity forearm exercise.
Nyberg, S K; Berg, O K; Helgerud, J; Wang, E
2017-04-01
The vascular strain is very high during heavy handgrip exercise, but the intensity and kinetics to reach peak blood flow, and peak oxygen uptake, are uncertain. We included 9 young (25 ± 2 yr) healthy males to evaluate blood flow and oxygen uptake responses during continuous dynamic handgrip exercise with increasing intensity. Blood flow was measured using Doppler-ultrasound, and venous blood was drawn from a deep forearm vein to determine arteriovenous oxygen difference (a-vO 2diff ) during 6-min bouts of 60, 80, and 100% of maximal work rate (WR max ), respectively. Blood flow and oxygen uptake increased ( P < 0.05) from 60%WR max [557 ± 177(SD) ml/min; 56.0 ± 21.6 ml/min] to 80%WR max (679 ± 190 ml/min; 70.6 ± 24.8 ml/min), but no change was seen from 80%WR max to 100%WR max Blood velocity (49.5 ± 11.5 to 58.1 ± 11.6 cm/s) and brachial diameter (0.49 ± 0.05 to 0.50 ± 0.06 cm) showed concomitant increases ( P < 0.05) with blood flow from 60% to 80%WR max, whereas no differences were observed in a-vO 2diff Shear rate also increased ( P < 0.05) from 60% (822 ± 196 s -1 ) to 80% (951 ± 234 s -1 ) of WR max The mean response time (MRT) was slower ( P < 0.05) for blood flow (60%WR max 50 ± 22 s; 80%WR max 51 ± 20 s; 100%WR max 51 ± 23 s) than a-vO 2diff (60%WR max 29 ± 9 s; 80%WR max 29 ± 5 s; 100%WR max 20 ± 5 s), but not different from oxygen uptake (60%WR max 44 ± 25 s; 80%WR max 43 ± 14 s; 100%WR max 41 ± 32 s). No differences were observed in MRT for blood flow or oxygen uptake with increased exercise intensity. In conclusion, when approaching maximal intensity, oxygen uptake appeared to reach a critical level at ~80% of WR max and be regulated by blood flow. This implies that high, but not maximal, exercise intensity may be an optimal stimulus for shear stress-induced small muscle mass training adaptations. NEW & NOTEWORTHY This study evaluated blood flow regulation and oxygen uptake during small muscle mass forearm exercise with high to maximal intensity. Despite utilizing only a fraction of cardiac output, blood flow reached a plateau at 80% of maximal work rate and regulated peak oxygen uptake. Furthermore, the results revealed that muscle contractions dictated bulk oxygen delivery and yielded three times higher peak blood flow in the relaxation phase compared with mean values. Copyright © 2017 the American Physiological Society.
Specific Intensity for Peaking: Is Race Pace the Best Option?
Munoz, Iker; Seiler, Stephen; Alcocer, Alberto; Carr, Natasha; Esteve-Lanao, Jonathan
2015-01-01
Background: The peaking period for endurance competition is characterized for a relative increase of the intensity of training, after a longer period of training relatively dominated by lower intensity and higher volume Objectives: The present study was designed to compare physiological and 10 km performance effects of high intensity training (HIT) versus race pace interval training (RP) during peaking for competition in well-trained runners. Patients and Methods: 13 athletes took part in the study, they were divided into two groups: HIT and RP. HIT performed short intervals at ~105% of the maximal aerobic velocity (MAV), while RP trained longer intervals at a speed of ~90% of the MAV (a speed approximating 10 km race pace). After 12 weeks of baseline training, the athletes trained for 6 weeks under one of the two peaking regimes. Subjects performed 10 km prior to and after the intervention period. The total load of training was matched between groups during the treatment phase. Subjects completed a graded treadmill running test until volitional exhaustion prior to each 10 km race. MAV was determined as the minimal velocity eliciting maximal oxygen consumption (VO2max). Results: Both groups significantly improved their 10 km time (35 minutes 29 seconds ± 1 minutes 41 seconds vs 34 minutes 53 seconds ± 1 minutes 55 seconds, P < 0.01 for HIT; 35 minutes 27 seconds ± 1 minutes 40 seconds vs 34 minutes 53 seconds ± 1 minutes 18 seconds P < 0.01 for RP). VO2max increased after HIT (69 ± 3.6 vs 71.5 ± 4.2 ml.Kg-1.min-1, P < 0.05); while it didn’t for RP (68.4 ± 6 vs 69.8 ± 3 ml.Kg-1.min-1, p>0.05). In contrast, running economy decreased significantly after HIT (210 ± 6 ml.Kg-1.km-1 vs 218 ± 9, P < 0.05). Conclusions: A 6 week period of training at either 105% of MAV or 90% of MAV yielded similar performance gains in a 10km race performed at ~90% MAV. Therefore, the physiological impact of HIT training seems to be positive for VO2max but negative for running economy. PMID:26448854
Dotta, Blake T; Lafrenie, Robert M; Karbowski, Lukasz M; Persinger, Michael A
2014-01-01
If parameters for lateral diffusion of lipids within membranes are macroscopic metaphors of the angular magnetic moment of the Bohr magneton then the energy emission should be within the visible wavelength for applied ~1 µT magnetic fields. Single or paired digital photomultiplier tubes (PMTs) were placed near dishes of ~1 million B16 mouse melanoma cells that had been removed from incubation. In very dark conditions (10(-11) W/m(2)) different averaged (RMS) intensities between 5 nT and 3.5 µT were applied randomly in 4 min increments. Numbers of photons were recorded directly over or beside the cell dishes by PMTs placed in pairs within various planes. Spectral analyses were completed for photon power density. The peak photon emissions occurred around 1 µT as predicted by the equation. Spectra analyses showed reliable discrete peaks between 0.9 and 1.8 µT but not for lesser or greater intensities; these peak frequencies corresponded to the energy difference of the orbital-spin magnetic moment of the electron within the applied range of magnetic field intensities and the standard solution for Rydberg atoms. Numbers of photons from cooling cells can be modified by applying specific intensities of temporally patterned magnetic fields. There may be a type of "cellular" magnetic moment that, when stimulated by intensity-tuned magnetic fields, results in photon emissions whose peak frequencies reflect predicted energies for fundamental orbital/spin properties of the electron and atomic aggregates with large principal quantum numbers.
Amin, Sanjiv B; Wang, Hongyue; Laroia, Nirupama; Orlando, Mark
2016-01-01
Objective To evaluate if unbound bilirubin is a better predictor of auditory neuropathy spectrum disorder (ANSD) than total serum bilirubin (TSB) or the bilirubin albumin molar ratio (BAMR) in late preterm and term neonates with severe jaundice (TSB ≥ 20 mg/dL or TSB that met exchange transfusion criteria). Study design Infants ≥ 34 weeks gestational age with severe jaundice during the first two weeks of life were eligible for the prospective observational study. A comprehensive auditory evaluation was performed within 72 hours of peak TSB. ANSD was defined as absent or abnormal auditory brainstem evoked response waveform morphology at 80 decibel click intensity in the presence of normal outer hair cell function. TSB, serum albumin, and unbound bilirubin were measured using the colorimetric, bromocresol green, and modified peroxidase method, respectively. Results Five of 44 infants developed ANSD. By logistic regression, peak unbound bilirubin but not peak TSB or peak BAMR was associated with ANSD (odds ratio 4.6, 95% CI: 1.6-13.5, p = 0.002). On comparing receiver operating characteristic curves, the area under the curve (AUC) for unbound bilirubin (0.92) was significantly greater (p = 0.04) compared with the AUC for TSB (0.50) or BAMR (0.62). Conclusions Unbound bilirubin is a more sensitive and specific predictor of ANSD than TSB or BAMR in late preterm and term infants with severe jaundice. PMID:26952116
Interleaved neuromuscular electrical stimulation: Motor unit recruitment overlap.
Wiest, Matheus J; Bergquist, Austin J; Schimidt, Helen L; Jones, Kelvin E; Collins, David F
2017-04-01
In this study, we quantified the "overlap" between motor units recruited by single pulses of neuromuscular electrical stimulation (NMES) delivered over the tibialis anterior muscle (mNMES) and the common peroneal nerve (nNMES). We then quantified the torque produced when pulses were alternated between the mNMES and nNMES sites at 40 Hz ("interleaved" NMES; iNMES). Overlap was assessed by comparing torque produced by twitches evoked by mNMES, nNMES, and both delivered together, over a range of stimulus intensities. Trains of iNMES were delivered at the intensity that produced the lowest overlap. Overlap was lowest (5%) when twitches evoked by both mNMES and nNMES produced 10% peak twitch torque. iNMES delivered at this intensity generated 25% of maximal voluntary dorsiflexion torque (11 Nm). Low intensity iNMES leads to low overlap and produces torque that is functionally relevant to evoke dorsiflexion during walking. Muscle Nerve 55: 490-499, 2017. © 2016 Wiley Periodicals, Inc.
[Effect of vibrational factors on the evaluation of whole-body vibrational intensity].
Suzuki, H
1997-12-01
The aim of this study is to obtain basic data useful to evaluate the riding comfort of railway vehicles. The apparatus used in the present experiment made it possible to simulate various vibrations of railway vehicles. Twenty-two adult subjects participated in this experiment. They were exposed to lateral vibration with varying peak and root mean square (rms) accelerations and frequencies. The types and ranges of vibrations used in this experiment approximated to the typical vibrations of railway vehicles. The subjects were asked to rate the intensity of each vibration given to them successively, using the 7-step rating scale. Results indicated that both peak and rms accelerations significantly affected for the evaluation, although the effect of frequency was not significant. As for interactions, it was found that there were significant interacting effects between frequency and peak acceleration, between frequency and rms acceleration, and between peak and rms accelerations. It was also found that the relationship between the rms acceleration and the evaluated score changed with varying peak accelerations.
Modeling of intense pulsed ion beam heated masked targets for extreme materials characterization
Barnard, John J.; Schenkel, Thomas
2017-11-15
Intense, pulsed ion beams locally heat materials and deliver dense electronic excitations that can induce material modifications and phase transitions. Material properties can potentially be stabilized by rapid quenching. Pulsed ion beams with pulse lengths of order ns have recently become available for materials processing. Here, we optimize mask geometries for local modification of materials by intense ion pulses. The goal is to rapidly excite targets volumetrically to the point where a phase transition or local lattice reconstruction is induced followed by rapid cooling that stabilizes desired material's properties fast enough before the target is altered or damaged by, e.g.,more » hydrodynamic expansion. By using a mask, the longitudinal dimension can be large compared to the transverse dimension, allowing the possibility of rapid transverse cooling. We performed HYDRA simulations that calculate peak temperatures for a series of excitation conditions and cooling rates of silicon targets with micro-structured masks and compare these to a simple analytical model. In conclusion, the model gives scaling laws that can guide the design of targets over a wide range of pulsed ion beam parameters.« less
Modeling of intense pulsed ion beam heated masked targets for extreme materials characterization
NASA Astrophysics Data System (ADS)
Barnard, John J.; Schenkel, Thomas
2017-11-01
Intense, pulsed ion beams locally heat materials and deliver dense electronic excitations that can induce material modifications and phase transitions. Material properties can potentially be stabilized by rapid quenching. Pulsed ion beams with pulse lengths of order ns have recently become available for materials processing. Here, we optimize mask geometries for local modification of materials by intense ion pulses. The goal is to rapidly excite targets volumetrically to the point where a phase transition or local lattice reconstruction is induced followed by rapid cooling that stabilizes desired material's properties fast enough before the target is altered or damaged by, e.g., hydrodynamic expansion. By using a mask, the longitudinal dimension can be large compared to the transverse dimension, allowing the possibility of rapid transverse cooling. We performed HYDRA simulations that calculate peak temperatures for a series of excitation conditions and cooling rates of silicon targets with micro-structured masks and compare these to a simple analytical model. The model gives scaling laws that can guide the design of targets over a wide range of pulsed ion beam parameters.
Irradiation effect on luminescence properties of fluoroperovskite single crystal (LiBaF3:Eu2+)
NASA Astrophysics Data System (ADS)
Daniel, D. Joseph; Madhusoodanan, U.; Nithya, R.; Ramasamy, P.
2014-03-01
Single crystals of pure and Eu2+ doped LiBaF3 have been grown from melt by using a vertical Bridgman-Stockbarger method. Effects induced by irradiation on europium doped LiBaF3 (lithium barium fluoride) single crystals were monitored by optical absorption, photoluminescence and thermoluminescence studies. The absorption bands of Eu2+ ions with peaks at 240, 290 and 320 nm were observed in the LiBaF3:Eu2+ crystal. Drastic increase in absorption was noted below 600 nm after gamma irradiation, which was dependent on the radiation dose. The additional absorption peak at around 570 nm was observed in irradiated crystal due to the ionization process Eu2+(-)e-→Eu3+. Photoluminescence of Eu2+ doped LiBaF3 single crystal shows sharp line peaked at ~359 nm and a broad band extending between 370 and 450 nm which shows a considerable reduction in Eu2+ PL intensity after gamma irradiation. Irradiated LiBaF3:Eu2+ sample has revealed three intense TL glow peaks at 128 °C (peak-1), 281 °C (peak-2) and 407 °C (peak-3). Activation energy (E) and frequency factor (s) of the latter two peaks were determined by various heating rate (VHR) method and graphical method.
Arad, Avigdor D; DiMenna, Fred J; Thomas, Naketa; Tamis-Holland, Jacqueline; Weil, Richard; Geliebter, Allan; Albu, Jeanine B
2015-08-15
The purpose of this randomized controlled clinical trial was to determine the effect of a 14-week high-intensity interval training (HIIT) intervention with weight stability on metabolic flexibility, insulin sensitivity, and cardiorespiratory fitness in sedentary, premenopausal, nondiabetic, overweight/obese African American women. Twenty-eight subjects were allocated to one of two groups: HIIT, which performed three sessions per week of four high-intensity cycling intervals, or a control group (CON), which maintained their normal level of physical activity. Diet was controlled for all subjects to ensure weight stability. Pre- and postintervention (pre/post), subjects completed an incremental cycling test to limit of tolerance and, following a 10-day high-fat controlled feeding period, a euglycemic-hyperinsulinemic clamp to determine insulin sensitivity and substrate oxidation. Nine members of HIIT (age, 29 ± 4 yr; body mass, 90.1 ± 13.8 kg) and eleven members of CON (age, 30 ± 7 yr; body mass, 85.5 ± 10.7 kg) completed the study. HIIT experienced an increased limit of tolerance (post, 1,124 ± 202 s; pre, 987 ± 146 s; P < 0.05), gas exchange threshold (post, 1.29 ± 0.34 liters/min; pre, 0.97 ± 0.23 liters/min; P < 0.05), and fat oxidation at the same absolute submaximal work rate compared with CON (P < 0.05 for group-by-time interaction in all cases). However, changes in peak oxygen consumption (V̇o2peak), insulin sensitivity, free fatty acid suppression during insulin stimulation, and metabolic flexibility were not different in HIIT compared with CON. High-intensity interval training with weight stability increased exercise fat oxidation and tolerance in subjects at risk for diabetic progression, but did not improve insulin sensitivity or fat oxidation in the postabsorptive or insulin-stimulated state. Copyright © 2015 the American Physiological Society.
Dynamical properties of total intensity fluctuation spectrum in two-mode Nd:YVO4 microchip laser
NASA Astrophysics Data System (ADS)
Zhang, Shao-Hui; Shu-Lian, Zhang; Tan, Yi-Dong; Sun, Li-Qun
2015-12-01
We investigate the total intensity fluctuation spectrum of the two-longitudinal- mode Nd:YVO4 microchip laser (ML). We find that low-frequency relaxation oscillation (RO) peaks still appear in the total intensity fluctuation spectrum, which is different from a previous research result that the low-frequency RO peaks exist in the spectrum of the individual mode but compensate for each other totally in the total intensity fluctuation spectrum. Taking the spatial hole-burning effect into account, one and two-mode rate equations for Nd:YVO4 ML laser are established and studied. Based on the theoretical model, we find that when the gains and losses for two longitudinal models are different, a low-frequency RO peak will appear in the total intensity fluctuation spectrum, while when they share the same gain and loss, the total spectrum will behave like that of a single mode laser. Theoretical simulation results coincide with experimental results very well. Project supported by the Beijing Higher Education Young Elite Teacher Project, China (Grant No. YETP0086), the Tsinghua University Initiative Scientific Research Programme, China (Grant No. 2012Z02166), and the Special-funded Programme on National Key Scientific Instruments and Equipment Development of China (Grant No. 2011YQ04013603).
Automatic peak selection by a Benjamini-Hochberg-based algorithm.
Abbas, Ahmed; Kong, Xin-Bing; Liu, Zhi; Jing, Bing-Yi; Gao, Xin
2013-01-01
A common issue in bioinformatics is that computational methods often generate a large number of predictions sorted according to certain confidence scores. A key problem is then determining how many predictions must be selected to include most of the true predictions while maintaining reasonably high precision. In nuclear magnetic resonance (NMR)-based protein structure determination, for instance, computational peak picking methods are becoming more and more common, although expert-knowledge remains the method of choice to determine how many peaks among thousands of candidate peaks should be taken into consideration to capture the true peaks. Here, we propose a Benjamini-Hochberg (B-H)-based approach that automatically selects the number of peaks. We formulate the peak selection problem as a multiple testing problem. Given a candidate peak list sorted by either volumes or intensities, we first convert the peaks into [Formula: see text]-values and then apply the B-H-based algorithm to automatically select the number of peaks. The proposed approach is tested on the state-of-the-art peak picking methods, including WaVPeak [1] and PICKY [2]. Compared with the traditional fixed number-based approach, our approach returns significantly more true peaks. For instance, by combining WaVPeak or PICKY with the proposed method, the missing peak rates are on average reduced by 20% and 26%, respectively, in a benchmark set of 32 spectra extracted from eight proteins. The consensus of the B-H-selected peaks from both WaVPeak and PICKY achieves 88% recall and 83% precision, which significantly outperforms each individual method and the consensus method without using the B-H algorithm. The proposed method can be used as a standard procedure for any peak picking method and straightforwardly applied to some other prediction selection problems in bioinformatics. The source code, documentation and example data of the proposed method is available at http://sfb.kaust.edu.sa/pages/software.aspx.
Automatic Peak Selection by a Benjamini-Hochberg-Based Algorithm
Abbas, Ahmed; Kong, Xin-Bing; Liu, Zhi; Jing, Bing-Yi; Gao, Xin
2013-01-01
A common issue in bioinformatics is that computational methods often generate a large number of predictions sorted according to certain confidence scores. A key problem is then determining how many predictions must be selected to include most of the true predictions while maintaining reasonably high precision. In nuclear magnetic resonance (NMR)-based protein structure determination, for instance, computational peak picking methods are becoming more and more common, although expert-knowledge remains the method of choice to determine how many peaks among thousands of candidate peaks should be taken into consideration to capture the true peaks. Here, we propose a Benjamini-Hochberg (B-H)-based approach that automatically selects the number of peaks. We formulate the peak selection problem as a multiple testing problem. Given a candidate peak list sorted by either volumes or intensities, we first convert the peaks into -values and then apply the B-H-based algorithm to automatically select the number of peaks. The proposed approach is tested on the state-of-the-art peak picking methods, including WaVPeak [1] and PICKY [2]. Compared with the traditional fixed number-based approach, our approach returns significantly more true peaks. For instance, by combining WaVPeak or PICKY with the proposed method, the missing peak rates are on average reduced by 20% and 26%, respectively, in a benchmark set of 32 spectra extracted from eight proteins. The consensus of the B-H-selected peaks from both WaVPeak and PICKY achieves 88% recall and 83% precision, which significantly outperforms each individual method and the consensus method without using the B-H algorithm. The proposed method can be used as a standard procedure for any peak picking method and straightforwardly applied to some other prediction selection problems in bioinformatics. The source code, documentation and example data of the proposed method is available at http://sfb.kaust.edu.sa/pages/software.aspx. PMID:23308147
Dalzill, Claudie; Nigam, Anil; Juneau, Martin; Guilbeault, Valérie; Latour, Elise; Mauriège, Pascale; Gayda, Mathieu
2014-04-01
The effects of an intensive lifestyle intervention including Mediterranean diet nutritional counselling and high-intensity interval training (HIIT) on body composition, cardiometabolic, and exercise parameters were studied in metabolically unhealthy obese (NMHO) and metabolically healthy but obese (MHO) subjects. Fifty-five MHO (51 ± 8 years; waist circumference, 109 ± 13 cm) and 79 NMHO subjects (54 ± 9 years; waist circumference, 112 ± 13 cm) participated in an intensive lifestyle modification program based on Mediterranean diet nutritional counselling and HIIT 2-3 times per week. Body composition, cardiometabolic, and exercise parameters were measured at baseline and after 9 months. Initially, MHO patients had a lower blood pressure (BP), fasting glycemia, triglycerides, and a higher high-density lipoprotein cholesterol and peak oxygen uptake (VO2 peak) (P < 0.05) vs NMHO patients. Body mass (P < 0.05), waist circumference (P < 0.0001), total and trunk fat mass (P < 0.001), systolic and diastolic BP (P < 0.001), fasting glucose (P < 0.0001), insulin sensitivity (P < 0.05), VO2 peak and muscle endurance (P < 0.0001) were similarly improved in both groups after the program. Prevalence of NMHO was reduced by 17.91% (P < 0.01) after the program. Similar improvements in body composition, BP, and exercise parameters were found for MHO and NMHO men and women (P < 0.05). In all patients, improvement of VO2 peak was negatively correlated with improvements in body composition, systolic blood pressure, and resting heart rate (HR) (R = -0.61 to -0.24; P < 0.05). A long-term intensive lifestyle program including Mediterranean diet nutritional counselling and HIIT is an appropriate intervention in MHO and NMHO subjects with similar potential clinical health benefits including an improved body composition, BP, fasting glycemia, insulin sensitivity, VO2 peak, and muscle endurance. Copyright © 2014 Canadian Cardiovascular Society. All rights reserved.
NASA Astrophysics Data System (ADS)
Lai, Hanh; McJunkin, Timothy R.; Miller, Carla J.; Scott, Jill R.; Almirall, José R.
2008-09-01
The combined use of SIMION 7.0 and the statistical diffusion simulation (SDS) user program in conjunction with SolidWorks® with COSMSOSFloWorks® fluid dynamics software to model a complete, commercial ion mobility spectrometer (IMS) was demonstrated for the first time and compared to experimental results for tests using compounds of immediate interest in the security industry (e.g., 2,4,6-trinitrotoluene, 2,7-dinitrofluorene, and cocaine). The effort of this research was to evaluate the predictive power of SIMION/SDS for application to IMS instruments. The simulation was evaluated against experimental results in three studies: (1) a drift:carrier gas flow rates study assesses the ability of SIMION/SDS to correctly predict the ion drift times; (2) a drift gas composition study evaluates the accuracy in predicting the resolution; (3) a gate width study compares the simulated peak shape and peak intensity with the experimental values. SIMION/SDS successfully predicted the correct drift time, intensity, and resolution trends for the operating parameters studied. Despite the need for estimations and assumptions in the construction of the simulated instrument, SIMION/SDS was able to predict the resolution between two ion species in air within 3% accuracy. The preliminary success of IMS simulations using SIMION/SDS software holds great promise for the design of future instruments with enhanced performance.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hanh Lai; Timothy R. McJunkin; Carla J. Miller
2008-09-01
The combined use of SIMION 7.0 and the statistical diffusion simulation (SDS) user program in conjunction with SolidWorks® with COSMSOFloWorks® fluid dynamics software to model a complete, commercial ion mobility spectrometer (IMS) was demonstrated for the first time and compared to experimental results for tests using compounds of immediate interest in the security industry (e.g., 2,4,6-trinitrotoluene and cocaine). The effort of this research was to evaluate the predictive power of SIMION/SDS for application to IMS instruments. The simulation was evaluated against experimental results in three studies: 1) a drift:carrier gas flow rates study assesses the ability of SIMION/SDS to correctlymore » predict the ion drift times; 2) a drift gas composition study evaluates the accuracy in predicting the resolution; and 3) a gate width study compares the simulated peak shape and peak intensity with the experimental values. SIMION/SDS successfully predicted the correct drift time, intensity, and resolution trends for the operating parameters studied. Despite the need for estimations and assumptions in the construction of the simulated instrument, SIMION/SDS was able to predict the resolution between two ion species in air within 3% accuracy. The preliminary success of IMS simulations using SIMION/SDS software holds great promise for the design of future instruments with enhanced performance.« less
NASA Astrophysics Data System (ADS)
Becker, J.; Pabst, H.; Mnyonga, J.; Kuzyakov, Y.
2015-07-01
Litterfall is one of the major pathways connecting above- and belowground processes. The effects of climate and land-use change on carbon (C) and nutrient inputs by litterfall are poorly known. We quantified and analyzed annual patterns of C and nutrient deposition via litterfall in natural forests and agroforestry systems along the unique elevation gradient of Mt. Kilimanjaro. Tree litter in three natural (lower montane, Ocotea and Podocarpus forests), two sustainably used (homegardens) and one intensively managed (shaded coffee plantation) was collected on a biweekly basis from May 2012 to July 2013. Leaves, branches and remaining residues were separated and analyzed for C and nutrient contents. The annual pattern of litterfall was closely related to rainfall seasonality, exhibiting a large peak towards the end of the dry season (August-October). This peak decreased at higher elevations with decreasing rainfall seasonality. Macronutrients (N, P, K) in leaf litter increased at mid elevation (2100 m a.s.l.) and with land-use intensity. Carbon content and micronutrients (Al, Fe, Mn, Na) however, were unaffected or decreased with land-use intensity. On the southern slope of Mt. Kilimanjaro, the annual pattern of litterfall depends on seasonal climatic conditions. While leaf litterfall decreased with elevation, total annual input was independent of climate. Compared to natural forests, the nutrient cycles in agroforestry ecosystems were accelerated by fertilization and the associated changes in dominant tree species.
Low-temperature photoluminescence study of thin epitaxial GaAs films on Ge substrates
NASA Astrophysics Data System (ADS)
Brammertz, Guy; Mols, Yves; Degroote, Stefan; Motsnyi, Vasyl; Leys, Maarten; Borghs, Gustaaf; Caymax, Matty
2006-05-01
Thin epitaxial GaAs films, with thickness varying from 140 to 1000 nm and different Si doping levels, were grown at 650 °C by organometallic vapor phase epitaxy on Ge substrates and analyzed by low-temperature photoluminescence (PL) spectroscopy. All spectra of thin GaAs on Ge show two different structures, one narrow band-to-band (B2B) structure at an energy of ~1.5 eV and a broad inner-band-gap (IB) structure at an energy of ~1.1 eV. Small strain in the thin GaAs films causes the B2B structure to be separated into a light-hole and a heavy-hole peak. At 2.5 K the good structural quality of the thin GaAs films on Ge can be observed from the narrow excitonic peaks. Peak widths of less than 1 meV are measured. GaAs films with thickness smaller than 200 nm show B2B PL spectra with characteristics of an n-type doping level of approximately 1018 at./cm3. This is caused by heavy Ge diffusion from the substrate into the GaAs at the heterointerface between the two materials. The IB structure observed in all films consists of two Gaussian peaks with energies of 1.04 and 1.17 eV. These deep trapping states arise from Ge-based complexes formed within the GaAs at the Ge-GaAs heterointerface, due to strong diffusion of Ge atoms into the GaAs. Because of similarities with Si-based complexes, the peak at 1.04 eV was identified to be due to a GeGa-GeAs complex, whereas the peak at 1.17 eV was attributed to the GeGa-VGa complex. The intensity of the IB structure decreases strongly as the GaAs film thickness is increased. PL intensity of undoped GaAs films containing antiphase domains (APDs) is four orders of magnitude lower than for similar films without APDs. This reduction in intensity is due to the electrically active Ga-Ga and As-As bonds at the boundaries between the different APDs. When the Si doping level is increased, the PL intensity of the APD-containing films is increased again as well. A film containing APDs with a Si doping level of ~1018 at./cm3 has only a factor 10 reduced intensity. We tentatively explain this observation by Si or Ge clustering at antiphase boundaries, which eliminates the effects of the Ga-Ga and As-As bonds. This assumption is confirmed by the fact that, at 77 K, the ratio between the intensity of the IB peak at 1.17 eV to the intensity of the peak at 1.04 eV is smaller than 1.4 for all films containing APDs, whereas it is larger than 1.4 for all films without APDs. This shows stronger clustering of Si or Ge in the material with APDs. For future electronic applications, Ge diffusion into the GaAs will have to be reduced. PL analysis will be a rapid tool for studying the Ge diffusion into the GaAs thin films.
NASA Technical Reports Server (NTRS)
Rinsland, Curtis P.; Smith, Mary Ann H.; Goldman, Aaron; Malathy Devi, V.
1991-01-01
Lorentz air-broadening coefficients and relative intensities have been measured for forty-three lines in the pure rotational band and twenty lines in the nu2 band of H2O-16 between 800 and 1150/cm. The results were derived from analysis of nine 0.017/cm-resolution atmospheric absorption spectra recorded over horizontal paths of 0.5-1.5 km with the McMath Fourier transform spectrometer and main solar telescope operated on Kitt Peak by the National Solar Observatory. A nonlinear least-squares spectral fitting technique was used in the spectral analysis. The results are compared with previous measurements and calculations. In most cases, the measured pressure-broadening coefficients and intensities are significantly different from the values in the 1986 HITRAN line parameters compilation.
Longitudinal Coupled-Bunch Instability Around 1 GHz at the CERN PS Booster
NASA Astrophysics Data System (ADS)
Schönauer, H.; Caspers, F.; Chanel, M.; Soby, L.; D'Yachkov, M.
1997-05-01
The fast-growing "Ring 4" instability occurring at intensities above 6.5 10^12 protons in the top one of the four PSB rings is finally explained by an asymmetry in the 42 vacuum pump manifolds common to all rings. Impedance measurements (wire method) and numerical calculations show a sharp resonant peak (Q 2000) at 1100 MHz and shunt impedances two times higher for the Ring 4 ports as compared to the other rings. This factor is sufficient to explain that the threshold of the instability falls below the maximum intensity only in Ring 4. A final, but labour-intensive and expensive, cure consists of inserting short-circuiting sleeves into all 168 beam ports. A temporary antidote is attempted by fitting ceramic damping resistors penetrating the top cavity through spare gauge ports. Results of beam and impedance measurements and of the cure will be presented and discussed.
Effect of different electrolytes on porous GaN using photo-electrochemical etching
NASA Astrophysics Data System (ADS)
Al-Heuseen, K.; Hashim, M. R.; Ali, N. K.
2011-05-01
This article reports the properties and the behavior of GaN during the photoelectrochemical etching process using four different electrolytes. The measurements show that the porosity strongly depends on the electrolyte and highly affects the surface morphology of etched samples, which has been revealed by scanning electron microscopy (SEM) images. Peak intensity of the photoluminescence (PL) spectra of the porous GaN samples was observed to be enhanced and strongly depend on the electrolytes. Among the samples, there is a little difference in the peak position indicating that the change of porosity has little influence on the PL peak shift, while it highly affecting the peak intensity. Raman spectra of porous GaN under four different solution exhibit phonon mode E 2 (high), A 1 (LO), A 1 (TO) and E 2 (low). There was a red shift in E 2 (high) in all samples, indicating a relaxation of stress in the porous GaN surface with respect to the underlying single crystalline epitaxial GaN. Raman and PL intensities were high for samples etched in H 2SO 4:H 2O 2 and KOH followed by the samples etched in HF:HNO 3 and in HF:C 2H 5OH.
NASA Astrophysics Data System (ADS)
Sarkar, A.; Chakrabarti, Mahuya; Sanyal, D.; Bhowmick, D.; Dechoudhury, S.; Chakrabarti, A.; Rakshit, Tamita; Ray, S. K.
2012-08-01
Low temperature photoluminescence and room temperature positron annihilation spectroscopy have been employed to investigate the defects incorporated by 6 MeV H+ ions in a hydrothermally grown ZnO single crystal. Prior to irradiation, the emission from donor bound excitons is at 3.378 eV (10 K). The irradiation creates an intense and narrow emission at 3.368 eV (10 K). The intensity of this peak is nearly four times that of the dominant near band edge peak of the pristine crystal. The characteristic features of the 3.368 eV emission indicate its origin as a ‘hydrogen at oxygen vacancy’ type defect. The positron annihilation lifetime measurement reveals a single component lifetime spectrum for both the unirradiated (164 ± 1 ps) and irradiated crystal (175 ± 1 ps). It reflects the fact that the positron lifetime and intensity of the new irradiation driven defect species are a little higher compared to those in the unirradiated crystal. However, the estimated defect concentration, even considering the high dynamic defect annihilation rate in ZnO, comes out to be ˜4 × 1017 cm-3 (using SRIM software). This is a very high defect concentration compared to the defect sensitivity of positron annihilation spectroscopy. A probable reason is the partial filling of the incorporated vacancies (positron traps), which in ZnO are zinc vacancies. The positron lifetime of ˜175 ps (in irradiated ZnO) is consistent with recent theoretical calculations for partially hydrogen-filled zinc vacancies in ZnO. Passivation of oxygen vacancies by hydrogen is also reflected in the photoluminescence results. A possible reason for such vacancy filling (at both Zn and O sites) due to irradiation has also been discussed.
THE FORMATION OF IRIS DIAGNOSTICS. VIII. IRIS OBSERVATIONS IN THE C ii 133.5 nm MULTIPLET
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rathore, Bhavna; Pereira, Tiago M. D.; Carlsson, Mats
The C ii 133.5 nm multiplet has been observed by NASA’s Interface Region Imaging Spectrograph (IRIS) in unprecedented spatial resolution. The aims of this work are to characterize these new observations of the C ii lines, place them in context with previous work, and to identify any additional value the C ii lines bring when compared with other spectral lines. We make use of wide, long exposure IRIS rasters covering the quiet Sun and an active region. Line properties such as velocity shift and width are extracted from individual spectra and analyzed. The lines have a variety of shapes (mostlymore » single-peak or double-peak), are strongest in active regions and weaker in the quiet Sun. The ratio between the 133.4 and 133.5 nm components is always less than 1.8, indicating that their radiation is optically thick in all locations. Maps of the C ii line widths are a powerful new diagnostic of chromospheric structures, and their line shifts are a robust velocity diagnostic. Compared with earlier quiet Sun observations, we find similar absolute intensities and mean line widths, but smaller redshifts; this difference can perhaps be attributed to differences in spectral resolution and spatial coverage. The C ii intensity maps are somewhat similar to those of transition region lines, but also share some features with chromospheric maps such as those from the Mg ii k line, indicating that they are formed between the upper chromosphere and transition region. C ii intensity, width, and velocity maps can therefore be used to gather additional information about the upper chromosphere.« less
Short latency compound action potentials from mammalian gravity receptor organs
NASA Technical Reports Server (NTRS)
Jones, T. A.; Jones, S. M.
1999-01-01
Gravity receptor function was characterized in four mammalian species using far-field vestibular evoked potentials (VsEPs). VsEPs are compound action potentials of the vestibular nerve and central relays that are elicited by linear acceleration ramps applied to the cranium. Rats, mice, guinea pigs, and gerbils were studied. In all species, response onset occurred within 1.5 ms of the stimulus onset. Responses persisted during intense (116 dBSPL) wide-band (50 to 50 inverted question mark omitted inverted question mark000 Hz) forward masking, whereas auditory responses to intense clicks (112 dBpeSPL) were eliminated under the same conditions. VsEPs remained after cochlear extirpation but were eliminated following bilateral labyrinthectomy. Responses included a series of positive and negative peaks that occurred within 8 ms of stimulus onset (range of means at +6 dBre: 1.0 g/ms: P1=908 to 1062 micros, N1=1342 to 1475 micros, P2=1632 to 1952 micros, N2=2038 to 2387 micros). Mean response amplitudes at +6 dBre: 1.0 g/ms ranged from 0.14 to 0.99 microV. VsEP input/output functions revealed latency slopes that varied across peaks and species ranging from -19 to -51 micros/dB. Amplitude-intensity slopes also varied ranging from 0.04 to 0.08 microV/dB for rats and mice. Latency values were comparable to those of birds although amplitudes were substantially smaller in mammals. VsEP threshold values were considerably higher in mammals compared to birds and ranged from -8.1 to -10.5 dBre 1.0 g/ms across species. These results support the hypothesis that mammalian gravity receptors are less sensitive to dynamic stimuli than are those of birds.
NASA Astrophysics Data System (ADS)
Anderson, D.; Andrais, B.; Mirzayans, R.; Siegbahn, E. A.; Fallone, B. G.; Warkentin, B.
2013-06-01
Microbeam radiation therapy (MRT) delivers single fractions of very high doses of synchrotron x-rays using arrays of microbeams. In animal experiments, MRT has achieved higher tumour control and less normal tissue toxicity compared to single-fraction broad beam irradiations of much lower dose. The mechanism behind the normal tissue sparing of MRT has yet to be fully explained. An accurate method for evaluating DNA damage, such as the γ-H2AX immunofluorescence assay, will be important for understanding the role of cellular communication in the radiobiological response of normal and cancerous cell types to MRT. We compare two methods of quantifying γ-H2AX nuclear fluorescence for uniformly irradiated cell cultures: manual counting of γ-H2AX foci by eye, and an automated, MATLAB-based fluorescence intensity measurement. We also demonstrate the automated analysis of cell cultures irradiated with an array of microbeams. In addition to offering a relatively high dynamic range of γ-H2AX signal versus irradiation dose ( > 10 Gy), our automated method provides speed, robustness, and objectivity when examining a series of images. Our in-house analysis facilitates the automated extraction of the spatial distribution of the γ-H2AX intensity with respect to the microbeam array — for example, the intensities in the peak (high dose area) and valley (area between two microbeams) regions. The automated analysis is particularly beneficial when processing a large number of samples, as is needed to systematically study the relationship between the numerous dosimetric and geometric parameters involved with MRT (e.g., microbeam width, microbeam spacing, microbeam array dimensions, peak dose, valley dose, and geometric arrangement of multiple arrays) and the resulting DNA damage.
Rushton, L; Romaniuk, H
1997-01-01
OBJECTIVES: To investigate the risk of leukaemia in workers in the petroleum distribution industry who were exposed to low levels of benzene. METHODS: From the cohort of distribution workers, 91 cases were identified as having leukaemia on either a death certificate or on cancer registration. These cases were compared with controls (four per case) randomly selected from the cohort, who were from the same company as the respective case, matched for age, and alive and under follow up at the time of case occurrence. Work histories were collected for the cases and controls, together with information about the terminals at which they had worked, fuel compositions, and occupational hygiene measurements of benzene. These data were used to derive quantitative estimates of personal exposure to benzene. Odds ratios (OR) were calculated conditional on the matching, to identify those variables in the study which were associated with risk of leukaemia. Examination of the potential effects of confounding and other variables was carried out with conditional logistic regression. Analyses were carried out for all leukaemia and separately for acute lymphoblastic, chronic lymphocytic, acute myeloid and monocytic, and chronic myeloid leukaemias. RESULTS: There was no significant increase in the overall risk of all leukaemias with higher cumulative exposure to benzene or with intensity of exposure, but risk was consistently doubled in subjects employed in the industry for > 10 years. Acute lymphoblastic leukaemia tended to occur in workers employed after 1950, who started work after the age of 30, worked for a short duration, and experienced low cumulative exposure with few peaks. The ORs did not increase with increasing cumulative exposure. The risk of chronic lymphocytic leukaemia seemed to be related most closely to duration of employment and the highest risk occurred in white collar workers with long service. These workers had only background levels of benzene exposure. There was no evidence of an association of risk with any exposure variables, and no evidence of an increasing risk with increasing cumulative exposure, mean intensity, or maximum intensity of exposure. The patterns of risk for acute myeloid and monocytic leukaemia were different from those of the lymphoid subgroups, in which duration of employment was the variable most closely related to risk. Risk was increased to an OR of 2.8 (95% confidence interval (95% CI) 0.8 to 9.4) for a cumulative exposure between 4.5 and 45 ppm-years compared with < 0.45 ppm-years. For mean intensity between 0.2 and 0.4 ppm an OR of 2.8 (95% CI 0.9 to 8.5) was found compared with < 0.02 ppm. Risk did not increase with cumulative exposure, maximum intensity, or mean intensity of exposure when treated as continuous variables. Cases of acute myeloid and monocytic leukaemia were more often classified as having peaked exposures than controls, and when variables characterising peaks, particularly daily and weekly peaks, were included in the analysis these tended to dominate the other exposure variables. However, because of the small numbers it is not possible to distinguish the relative influence of peaked and unpeaked exposures on risk of acute myeloid and monocytic leukaemia. There was no evidence of an increased risk of chronic myeloid leukaemia with increases in cumulative exposure, maximum intensity, mean intensity, and duration of employment, either as continuous or categorical variables. Analyses exploring the sensitivity of the results to the source and quality of the work histories showed similar patterns in general. However, no increases in ORs for categories of cumulative exposure were found for acute myeloid and monocytic leukaemia in the data set which included work histories obtained from personnel records still in existence, although numbers were reduced. Analyses excluding the last five and 10 years of exposure showed a tendency for ORs to reduce for chronic lymphocytic leukaemia and chronic myeloid leukaemia, and to increase for acute myeloid and monocytic leukaemia. Limitations of the study include uncertainties and gaps in the information collected, and small numbers in subcategories of exposure which can lead to wide CIs around the risk estimates and poor fit of the mathematical models. CONCLUSIONS: There is no evidence in this study of an association between exposure to benzene and lymphoid leukaemia, either acute or chronic. There is some suggestion of a relation between exposure to benzene and myeloid leukaemia, in particular for acute myeloid and monocytic leukaemia. Peaked exposures seemed to be experienced for this disease. However, in view of the limitations of the study, doubt remains as to whether the risk of acute myeloid and monocytic leukaemia is increased by cumulative exposures of < 45 ppm-years. Further work is recommended to review the work histories and redefine their quality, to explore the discrepancies between results for categorical and continuous variables, and to develop ranges around the expose estimates to enable further sensitivity analyses to be carried out. PMID:9155776
Cardiorespiratory responses of a dance session designed for older women: A cross sectional study.
Rodrigues-Krause, Josianne; Farinha, Juliano Boufleur; Ramis, Thiago Rozales; Boeno, Francesco Pinto; Dos Santos, Gabriela Cristina; Krause, Mauricio; Reischak-Oliveira, Alvaro
2018-06-04
Dancing has been increasingly used as a type of exercise intervention to improve cardiovascular fitness of older people. However, it is unclear which may be the exercise intensity of the dance sessions. To describe cardiorespiratory responses of a dance session for older women, and to identify intensity zones in relation to peak oxygen consumption (VO 2 peak), first and second ventilatory thresholds (VT1 and VT2). Ten women (66 ± 5 yrs., BMI 27 ± 4) were examined on three occasions: Familiarization, maximum effort and dance sessions. Incremental treadmill test: 5 km/h, 2% slope each min, until maximum effort. Dance class (60 min): warm-up (20 min), across-the-floor (10 min), choreography (15 min), show (10 min) and cool-down (5 min). Ventilatory parameters were measured continuously (breath-by-breath). VO 2 (mL·kg -1 ·min -1 ): Maximum effort: VO 2 peak (23.3 ± 4.3), VT1 (17.2 ± 3.5) and VT2 (20.9 ± 3.4). Dancing: warm-up (12.8 ± 2.4, ~55%VO 2 peak), across-the-floor (14.2 ± 2.4 ~62%VO 2 peak), choreography (14.6 ± 3.2 ~63%VO 2 peak) and show (16.1 ± 3.3, ~69% VO 2 peak). Show was similar to VT1. Cardiorespiratory demands of a dance class for older women are at low aerobic intensity. Show was similar to VT1, indicating that a dance class may be modulated to improve aerobic fitness, at least at initial stages of training. Copyright © 2018 Elsevier Inc. All rights reserved.
Rainfall and Erosion Response Following a Southern California Wildfire
NASA Astrophysics Data System (ADS)
Wohlgemuth, P. M.; Robichaud, P. R.; Brown, R. E.
2011-12-01
Wildfire renders landscapes susceptible to flooding and accelerated surface erosion. Consumption of the vegetation canopy and the litter or duff layer removes resistances to the agents of erosion. Moreover, changes in soil properties can restrict infiltration, increasing the effectiveness of the driving forces of rainsplash and surface runoff. However, it is unclear whether surface erosion varies linearly with rainfall amounts and intensities or if thresholds exist beyond which erosion increases in a different trajectory. The Santiago Fire burned over 11000 ha in northeastern Orange County, California in October 2007. The burn area consists of a deeply dissected mountain block underlain by sedimentary and metamorphic rocks that produce erosive soils. Regional erosion and sediment transport is triggered by winter cyclonic storms. Recording raingages were deployed across a vertical gradient within the burned area and silt fences were constructed to monitor hillslope erosion. During the study period initial storms were characterized by moderate rainfall (amounts less than 25 mm with peak 10-minute intensities of less than 10 mm per hr). Surface erosion was concomitantly minor, less than 0.4 Mg per ha. However, an unusual thunderstorm in late May 2008 produced spatially variable rainfall and consequent surface erosion across the study area. The raingage at a lower elevation site measured 41.4 mm of rain for this storm with a peak 10-minute intensity of 81 mm per hr. The silt fences were overtopped, yielding a minimum value of 18.5 Mg per ha. In contrast, the raingage at an upper elevation site recorded 19.6 mm of rain with a peak 10-minute intensity of 50 mm per hr. Surface erosion in the higher elevation sites was negligible (0.1 Mg per ha). Subsequently, individual storms exceeded 100 mm of rainfall but peak 10-minute intensities never approached those of the May thunderstorm. Erosion was moderate (mostly less than 5 Mg per ha), albeit influenced by the presence of regrowing vegetation. We therefore believe that surface erosion in the immediate postfire environment is more related to storm intensity than rainfall amount. Even allowing for site-to-site differences and site changes over the first postfire winter season, it is clear that some threshold in erosion response was crossed at the lower elevation sites during the May 2008 thunderstorm. We suggest that this represents a threshold of peak 10-minute intensity of between 50 and 80 mm per hr.
Bogdanis, G C; Stavrinou, P; Fatouros, I G; Philippou, A; Chatzinikolaou, A; Draganidis, D; Ermidis, G; Maridaki, M
2013-11-01
This study investigated the changes in oxidative stress biomarkers and antioxidant status indices caused by a 3-week high-intensity interval training (HIT) regimen. Eight physically active males performed three HIT sessions/week over 3 weeks. Each session included four to six 30-s bouts of high-intensity cycling separated by 4 min of recovery. Before training, acute exercise elevated protein carbonyls (PC), thiobarbituric acid reactive substances (TBARS), glutathione peroxidase (GPX) activity, total antioxidant capacity (TAC) and creatine kinase (CK), which peaked 24h post-exercise (252 ± 30%, 135 ± 17%, 10 ± 2%, 85 ± 14% and 36 ± 13%, above baseline, respectively; p<0.01), while catalase activity (CAT) peaked 30 min post-exercise (56 ± 18% above baseline; p<0.01). Training attenuated the exercise-induced increase in oxidative stress markers (PC by 13.3 ± 3.7%; TBARS by 7.2 ± 2.7%, p<0.01) and CK activity, despite the fact that total work done was 10.9 ± 3.6% greater in the post- compared with the pre-training exercise test. Training also induced a marked elevation of antioxidant status indices (TAC by 38.4 ± 7.2%; CAT by 26.2 ± 10.1%; GPX by 3.0 ± 0.6%, p<0.01). Short-term HIT attenuates oxidative stress and up-regulates antioxidant activity after only nine training sessions totaling 22 min of high intensity exercise, further supporting its positive effect not only on physical conditioning but also on health promotion. Copyright © 2013 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gupta, Rajkumar, E-mail: rkg@rract.gov.in; Modi, Mohammed H.; Lodha, G. S.
Soft x-ray spectra of the toroidal grating monochromator (TGM) at the reflectivity beamline of Indus-1 synchrotron source are analyzed for higher harmonic contribution. A diffraction grating of central line spacing 1200 l/mm is used to disperse the monochromatic beam received from TGM to quantify the harmonic contents in the 50–360 Å wavelength range. In order to calculate the harmonic contamination, conventionally the intensity of higher order peak is divided by first order peak intensity of the desired wavelength. This approach is found to give wrong estimate as first order peak itself is overlapped by higher order peaks. In the presentmore » study, a modified approach has been proposed to calculate harmonic contamination where the intensity contributions of overlapping orders have been removed from the first order diffraction peak of the desired wavelength. It is found that the order contamination in the TGM spectra is less than 15% in the wavelength range of 90–180 Å. The total harmonic contribution increases from 6%–60% in the wavelength range of 150–260 Å. The critical wavelength of Indus-1 is 61 Å hence the harmonic contamination below 90 Å is significantly low. The results obtained with modified approach match well with those obtained by quantitative analysis of multilayer reflectivity data. The obtained higher harmonics data are used to fit the transmission of aluminum edge filter in the 120–360 Å wavelength range.« less
NASA Astrophysics Data System (ADS)
Blanch, E.; Altadill, D.
2009-04-01
Geomagnetic storms disturb the quiet behaviour of the ionosphere, its electron density and the electron density peak height, hmF2. Many works have been done to predict the variations of the electron density but few efforts have been dedicated to predict the variations the hmF2 under disturbed helio-geomagnetic conditions. We present the results of the analyses of the F2 layer peak height disturbances occurred during intense geomagnetic storms for one solar cycle. The results systematically show a significant peak height increase about 2 hours after the beginning of the main phase of the geomagnetic storm, independently of both the local time position of the station at the onset of the storm and the intensity of the storm. An additional uplift is observed in the post sunset sector. The duration of the uplift and the height increase are dependent of the intensity of the geomagnetic storm, the season and the local time position of the station at the onset of the storm. An empirical model has been developed to predict the electron density peak height disturbances in response to solar wind conditions and local time which can be used for nowcasting and forecasting the hmF2 disturbances for the middle latitude ionosphere. This being an important output for EURIPOS project operational purposes.
NASA Astrophysics Data System (ADS)
Huang, Tai-Yin
2018-06-01
Variations of airglow intensity, Volume Emission Rate (VER), and VER peak height induced by the CO2 increase, and by the F10.7 solar cycle variation and geomagnetic activity were investigated to quantitatively assess their influences on airglow. This study is an extension of a previous study by Huang (2016) covering a time period of 55 years from 1960 to 2015 and includes geomagnetic variability. Two airglow models, OHCD-90 and MACD-90, are used to simulate the induced variations of O(1S) greenline, O2(0,1) atmospheric band, and OH(8,3) airglow for this study. Overall, our results demonstrate that airglow intensity and the peak VER variations of the three airglow emissions are strongly correlated, and in phase, with the F10.7 solar cycle variation. In addition, there is a linear trend, be it increasing or decreasing, existing in the airglow intensities and VERs due to the CO2 increase. On other hand, airglow VER peak heights are strongly correlated, and out of phase, with the Ap index variation of geomagnetic activity. The CO2 increase acts to lower the VER peak heights of OH(8,3) airglow and O(1S) greenline by 0.2 km in 55 years and it has no effect on the VER peak height of O2(0,1) atmospheric band.
Zhu, Jinghui; Qin, Mingyou; Liu, Shaopu; Liu, Zhongfang; Yang, Jidong; Hu, Xiaoli
2014-09-15
A flow injection analysis (FIA) system combined with dual-wavelength overlapping resonance Rayleigh scattering (DWO-RRS) has been established and validated for rapid determination of malachite green (MG) and its metabolite in fish samples. Under experimental condition, MG would react with Erythrosin (Ery) to form ion-association complexes, resulting in the occurrence of two RRS peaks and a dramatic enhancement of RRS intensity. The maximum RRS peaks were located at 286 nm and 337 nm. It is noted that the increments of both of these two peaks were proportional to the concentration of MG. The detection limit of DWO-RRS was 1.5 ng/mL, which was comparable to several reported methods. Moreover, the results of real sample analysis exhibited an acceptable recovery between 97.5% and 103.6%, indicating that the method had good reproducibility. Copyright © 2014 Elsevier B.V. All rights reserved.
Fourier-transform infrared spectroscopy (FTIR) analysis of triclinic and hexagonal birnessites
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ling, Florence T.; Post, Jeffrey E.; Heaney, Peter J.
The characterization of birnessite structures is particularly challenging for poorly crystalline materials of biogenic origin, and a determination of the relative concentrations of triclinic and hexagonal birnessite in a mixed assemblage has typically required synchrotron-based spectroscopy and diffraction approaches. In this study, Fourier-transform infrared spectroscopy (FTIR) is demonstrated to be capable of differentiating synthetic triclinic Na-birnessite and synthetic hexagonal H-birnessite. Furthermore, IR spectral deconvolution of peaks resulting from Mnsingle bondO lattice vibrations between 400 and 750 cm - 1 yield results comparable to those obtained by linear combination fitting of synchrotron X-ray absorption fine structure (EXAFS) data when applied tomore » known mixtures of triclinic and hexagonal birnessites. Density functional theory (DFT) calculations suggest that an infrared absorbance peak at ~ 1628 cm - 1 may be related to OH vibrations near vacancy sites. The integrated intensity of this peak may show sensitivity to vacancy concentrations in the Mn octahedral sheet for different birnessites.« less
Synthesis and Photoluminescence of Single-Crystalline Fe(III)-Doped CdS Nanobelts.
Kamran, Muhammad Arshad; Zou, Bingsuo; Majid, A; Alharbil, Thamer; Saeed, M A; Abdullah, Ali; Javed, Qurat-ul-ain
2016-04-01
In this paper, we report the synthesis and optical properties of Fe(III) doped CdS nanobelts (NBs) via simple Chemical Vapor Deposition (CVD) technique to explore their potential in nano-optics. The energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) analysis manifested the presence of Fe(III) ions in the NBs subsequently confirmed by the peak shifting to lower phonon energies as recorded by Raman spectra and shorter lifetime in ns. Photoluminescence (PL) spectrum investigations of the single Fe(III)-doped CdS NBs depicted an additional PL peak centered at 573 nm (orange emission) in addition to the bandedge(BE) emission. The redshift and decrease in the BE intensity of the PL peaks, as compared to the bulk CdS, confirmed the quenching of spectra upon Fe doping. The synthesis and orange emission for Fe-doped CdS NBs have been observed for the first time and point out their potential in nanoscale devices.
NASA Astrophysics Data System (ADS)
Du, Yong; Zhang, Xiaoyu; Jiang, Binbin; Huang, Dasong; Yao, Lingling
2015-04-01
In this paper, a total of 28 water samples were collected mainly from three sections(C section in the Yangtze river inner estuary, PN section and F section on the spindle of Changjiang diluted water influenced by different hydrodynamic processes),which taken on two cruises in spring and summer of 2011. Absorption and fluorescence spectroscopy were measured along with dissolved organic carbon(DOC) concentrations and temperature, salinity and another environmental parameters to characterize the material sources and environmental implications of dissolved organic matter(DOM). Two protein-like components(tyrosine-like peak B and tryptophan-like peak T1), and two humic-like components(marine humic-like peak M and ultraviolet region humic-like peak A ) were identified by PARAFAC. We discussed CDOM distribution characteristic, material composition, and influence factors during the slowly dilution process of Changjiang diluted water into the east China sea by comparing the correlation of the CDOM absorption, fluorescence intensity, and fluorescence peak with DOC, in order to provide the based biogeochemistry theory basis for building DOC implications using CDOM fluorescence properties. The results revealed that:1) the Yangtze river and its inner estuary (upstream of the river mouth) were detected a higher amount of humic-like components. With the rapid dilution (or settlement) at the inner estuary, the humic-like components would further spread and dilute slowly on PN section and F section. On PN section, the terrigenous material is the main source material, and the main mechanism of CDOM distribution characteristics is controlled by dilution diffusion. Affected by the water mass convergence, marine dissolved organic matter in local waters had obvious input. However, due to the complexed hydrodynamic environment on F section, the input of terrigenous material has many ways. The influence of marine dissolved organic matter increased with the offshore distance increases.2) Although the absorption coefficient of DOC has good instruction significance, CDOM fluorescence intensity can more accurately express the amount of DOC in water than that of absorption coefficient with the source of dissolved organic matter enhanced.3) In general, CDOM fluorescence intensity and DOC show good linear relationship in the study region. But the correlation would change in different sea, and may ignore the rapidly dilution(or possibly sedimentation process) of estuarine waters, which need to be further depth study. Keywords: CDOM; F section; PN section; sources tracing; hydrodynamic environment
Coquart, Jeremy B; Boitel, Guillaume; Borel, Benoit; Duhamel, Alain; Matran, Regis; Delsart, Pascal; Mounier-Vehier, Claire; Garcin, Murielle
2017-01-01
This study investigated the effects of an exercise program at the intensity corresponding to the crossover point of substrate utilization (COP) on anthropometric measures, health-related quality of life (HRQoL) and cardiorespiratory fitness (i.e., peak oxygen uptake [V̇O2peak] and peak power output [Ppeak]) in women with metabolic syndrome (MetS). Nineteen obese and post-menopausal women with MetS (age: 54.8±8.1 years, body mass: 89.0±12.2 kg, Body Mass Index: 34.5±4.0 kg/m2) followed a 12-week program consisting of three 45-minute sessions per week of cycle ergometer exercise. The imposed exercise intensity corresponded to COP. Before and after the program, HRQoL, V̇O2peak and Ppeak were measured and then compared. Body mass (89.0±12.2 vs. 86.2±11.0 kg), Body Mass Index (34.5±4.0 vs. 33.4±3.6 kg/m2), waist (106±10 vs. 100±9 cm) and hip (117±11 vs. 114±11 cm) circumferences, waist-to-hip ratio (0.91±0.07 vs. 0.88±0.07), fat mass (43.3±4.6 vs. 41.9±4.6%), fat-free mass (56.7±4.6 vs. 58.2±4.6%), V̇O2peak (16.6±3.4 vs. 18.1±4.1 mL/min/kg) and Ppeak (102±22 vs. 125±27 W) were significantly improved after the exercise program (P<0.05), but HRQoL showed no significant improvement on any subscale (i.e., physical functioning: performance limitation for physical activities including bathing and dressing, role physical: problems with work or other daily activities, bodily pain, general health, vitality, social functioning, role emotional and mental health; P>0.05). Although a 12-week exercise program at COP improved anthropometric measures and cardiorespiratory fitness in women with MetS, self-perceived HRQoL did not significantly improve. This finding may be linked to a significant but still insufficient reduction in body mass, probably because COP is too weak exercise intensity to induce important energy expenditure.
Characterising the slope of the distance-time relationship in swimming.
Dekerle, J; Brickley, G; Alberty, M; Pelayo, P
2010-05-01
The aim of the present study was to assess whether the critical speed calculated by the slope of the distance-time relationship (S(d-t)) represents the boundary between the heavy and severe intensity domains in swimming and would be sustainable during intermittent exercise. Nine competitive male swimmers (mean+/-SD: aged 21.2+/-2.6 yrs; peak (.)VO2 of 3866+/-529 mL min(-1)) performed, (a) four fixed-distance (100-200-400-800 m) all-out efforts to determine S(d-t) and peak (.)VO2; (b) three constant-speed efforts to exhaustion (TTE) at and 5% above and below S(d-t) (S(d-t)(+5%) and S(d-t)(-5%), respectively); (c) a set of 10 x 400 m at S(d-t) with 40-s recovery in between. Capillary blood lactate concentration ([La](B)), oxygen uptake ((.)VO2), and RPE remained stable at S(d-t)(-5%) (TTE=48.9+/-14.1 min) with end values of 3.8+/-1.9 mmol L(-1), 87+/-14% peak (.)VO2, and 4.7+/-1.3. TTE decreased at S(d-t)(+5%) (8.6+/-3.1 min), with end [La](B) of 10.2+/-1.9 mmol L(-1). Peak (.)VO2 was reached at exhaustion. Similarly, S(d-t) could only be maintained for 24.3+/-7.7 min with an increase in RPE and [La](B), (.)VO2 reaching its peak (95+/-5% peak VO2). RPE increased but [La](B) remained stable throughout the ten 400 m blocks performed at S(d-t) (overall time of 53.9+/-2.7 min). The physiological responses when swimming 5% below and 5% above S(d-t) are those characterising the heavy and severe intensity domain, respectively. While S(d-t) lies within the severe intensity domain, intermittent swims at this intensity induce [La](B) steady state alongside high rates of perceived exertion. 2009 Sports Medicine Australia. All rights reserved.
[Effects of different annealing conditions on the photoluminescence of nanoporous alumina film].
Xie, Ning; Ma, Kai-Di; Shen, Yi-Fan; Wang, Qian
2013-12-01
The nanoporous alumina films were prepared by two-step anodic oxidation in 0.5 mol L-1 oxalic acid electrolyte at 40 V. Photoluminescence (PL) of nanoporous alumina films was investigated under different annealing atmosphere and different temperature. The authors got three results about the PL measurements. In the same annealing atmosphere, when the annealling temperature T< or =600 degreeC, the intensity of the PL peak increases with elevated annealing temperature and reaches a maximum value at 500 degreeC, but the intensity decreases with a further increase in the annealing temperature, and the PL peak intensity of samples increases with the increase in the annealing temperature when the annealling temperature T> or =800 degreeC. In the different annealling atmosphere, the change in the photoluminescence peak position for nanoporous alumina films with the increase in the annealing temperature is different: With the increase in the annealling temperature, the PL peak position for the samples annealed in air atmosphere is blue shifted, while the PL peak position for the samples annealed in vacuum atmosphere will not change. The PL spectra of nanoporous alumina films annealed at 1100 degreeC in air atmosphere can be de-convoluted by three Gaussian components at an excitation wavelength of 350 nm, with bands centered at 387, 410 and 439 nm, respectively. These results suggest that there might be three luminescence centers for the PL of annealed alumina films. At the same annealling temperature, the PL peak intensity of samples annealed in air atmosphere is stronger than that annealed in the vacuum. Based on the experimental results and the X-ray dispersive energy spectrum (EDS) combined with infrared reflect spectra, the luminescence mechanisms of nanoporous alumina films are discussed. There are three luminescence centers in the annealed nanoporous alumina films, which originate from the F center, F+ center and the center associated with the oxalic impurities. The effects of different annealing conditions on the photoluminescence of nanoporous alumina film are reasonably explained.
Influence of pitting defects on quality of high power laser light field
NASA Astrophysics Data System (ADS)
Ren, Huan; Zhang, Lin; Yang, Yi; Shi, Zhendong; Ma, Hua; Jiang, Hongzhen; Chen, Bo; Yang, XiaoYu; Zheng, Wanguo; Zhu, Rihong
2018-01-01
With the split-step-Fourier-transform method for solving the nonlinear paraxial wave equation, the intensity distribution of the light field when the pits diameter or depth change is obtained by using numerical simulation, include the intensity distribution inside optical element, the beam near-field, the different distances behind the element and the beam far-field. Results show that with the increase of pits diameter or depth, the light field peak intensity and the contrast inside of element corresponding enhancement. The contrast of the intensity distribution of the rear surface of the element will increase slightly. The peak intensity produced by a specific location element downstream of thermal effect will continue to increase, the damage probability in optics placed here is greatly increased. For the intensity distribution of the far-field, increase the pitting diameter or depth will cause the focal spot intensity distribution changes, and the energy of the spectrum center region increase constantly. This work provide a basis for quantitative design and inspection for pitting defects, which provides a reference for the design of optical path arrangement.