One-minute Interval Research Articles

A NEW SIMPLE TEST FOR MAXIMAL MUSCLE POWER IN HEALTH AND FITNESS FACILITIES

Age related changes of muscle power and its impact on physical activity pattern, physical performance and quality of life demand a simple assessment strategy. Our aim is to present reliability data in a new simple protocol for muscle power assessment previously proposed by Araújo (2000). Eighteen physically active healthy young adults (12 women), unaccustomed to resistance training, participated in the study. They were initially subjected to an 1-RM testing with simultaneous measurement of velocity, power (Fitrodyne, Bratislava) in an upright row exercise, performed up to mesosternal level in standing position, in order to determine maximal power (MP) and the corresponding load (LMP) in power-load curve. In the following week, they returned in five consecutive days to perform 2x2 reps (3-sec interval among reps) at LMP using maximal velocity in the concentric phase. In one of the days, following a latin-square design, they performed 10x2 reps with one-minute interval among sets. Best results among reps were chosen for further analysis. One-way repeated measures ANOVA and Bonferroni t-tests showed that mean MP results in the 5 consecutive days did not differ (p = .69, ranging from 262 to 267 Watts). Looking to individual data variability, values of 3 and 8% were found respectively for CV and to the mean of range of scores divided by mean (M-m/X) (maximum minus minimum score divided by the subject's mean). Analyzing intraday reliability in the 10 consecutive sets û mean results (ranging from 242 to 263 Watts), only two significant differences were found û set 1 vs sets 4 and 6 û (p < .05). If set 1 data were excluded (5 of the 18 subjects performed very low values in this set), no significant differences could be detected (p = .13). Individual variability data showed 6 and 20%, respectively for CV and M-m/X. We conclude that MP obtained in this simple test presents high intra and interdays reliability with relatively low variability, that compares well with other measurements often used in exercise sciences. The method can be recommended for muscle power assessment in health and fitness facilities, where the utilization of more sophisticated devices and protocols are unsuitable.

RESPONSE OF GREEN-AMPT MEIN-LARSEN SIMULATED RUNOFF VOLUMES TO TEMPORALLY AGGREGATED PRECIPITATION

ABSTRACT: Data collection frequency in automated systems is user determined and can range from seconds to hours or days. Currently, there is no standard or recommended frequency interval for collecting precipitation data from automated systems for input to event-based models such as Green-Ampt Mein-Larsen (GAML). Data from 47 storm events at seven locations were used to simulate the response of GAML excess rainfall to temporally aggregated precipitation data. No difference in model efficiency was recognized when comparing one-minute interval data (R2= 1.00) to five-minute data (R2= 1.00). Very little model efficiency was lost at a 10-minute (R2= 0.96) interval. After 10-minutes, decline in efficiency became more rapid with R2= 0.16 at one hour. The combined effect of time interval with respect to drainage area, hydraulic conductivity, maximum 30-minute intensity, and total precipitation also revealed similar results.

Initial development of precipitation and onset of cloud electrification in thunderstorms at Pune

Using one-minute interval data of electric field and the records of rainfall measured at the ground surface, time sequence in the initial registration of precipitation and the onset of cloud electrification was examined for a series of 14 thunderstorms of the year 1973 at Pune to study the relationship between the initial development of precipitation and intensification of cloud electrification. The combined result of the 14 storms studied, each of which yielded precipitation, indicated in-cloud development of precipitation at least 3-7 minutes in advance of onset of cloud electrification. It is inferred from the other supplementing studies published by other workers and from the above result that in most cases the precipitation development in thunderstorms is initiated well before the electric field begins to intensify. This result is in close agreement with the result of previous studies.

SOES Trading and Market Volatility

The National Association of Security Dealers alleges that professional-trader use of the Small Order Execution System (SOES) causes greater security price volatility. We docu? ment bidirectional Granger causality between a proxy for professional SOES trading (the frequency of maximum-sized SOES trades) and a measure of stock price volatility. We find that high levels of volatility precede high levels of maximum-sized SOES trades, suggesting that volatility causes more frequent large SOES trades. Likewise, over a one-minute time interval, high levels of maximum-sized SOES trades cause high volatility. Over longer periods, however, intense maximum-sized SOES trading causes lower volatility. Inter? preted in conjunction with Harris and Schultz (1997), these results suggest that high levels of maximum-sized SOES trades lead to more efficient price discovery. In light of these results, we believe that efforts to eliminate SOES based on volatility considerations are unwarranted.

Rocuronium priming of atracurium-induced neuromuscular blockade: The use of short priming intervals

Study Objective: To evaluate the effects of priming doses of rocuronium on the duration of priming interval and on the outcome of priming sequence using rocuronium-atracurium combination. Design: Three phase, randomized, controlled study. Setting: Inpatient anesthesia in a university hospital. Patients: 144 ASA physical status I and II patients, 19 to 57 years of age, weighing 50 to 90 kg, and undergoing low-risk elective surgery. Interventions: Phase I, two equal groups (n = 12) of adult patients anesthetized with propofol, fentanyl, and nitrous oxide (N 2O), received a priming dose of rocuronium 0.1 mg/kg or vecuronium 0.015 mg/kg. Phase II included six equal groups (n = 12): Groups 1, 2, and 3 received a priming dose of rocuronium 0.1 mg/kg and atracurium 0.42 mg/kg for intubation. The priming intervals were, respectively, 1, 1.5, or 2 minutes in Groups 1, 2, and 3. Groups 4, 5, and 6 received, respectively, a bolus dose of rocuronium 0.6 mg/kg, atracurium 0.5 mg/kg, or succinylcholine 1 mg/kg. Intubation was performed at maximum block. Phase III included four equal groups (n = 12). A priming dose of rocuronium 0.1 mg/kg (Group 1) or a placebo (Groups 2, 3, and 4) was given to awake patients. Anesthesia was induced during the one-minute priming interval. Intubating doses of atracurium 0.42 mg/kg, rocuronium 0.6 mg/kg, atracurium 0.5 mg/kg, or succinylcholine 1 mg/kg were given to Groups 1, 2, 3, and 4, respectively. Intubation was attempted 1 minute after intubating doses were administered. Measurements and Main Results: Adductor pollicis response to train-of-four stimulation was recorded mechanically in Phases I and II only. The priming interval after rocuronium 0.1 mg/kg was in the range of 1 to 2 minutes. Priming doses of rocuronium resulted in significant acceleration in the onset time of intubating doses of atracurium, irrespective of the duration of the priming interval. The onset times [mean (SD)] following rocuronium-atracurium sequence in Groups 1, 2, and 3 were, respectively, 67 (17), 73 (14), and 66 (18) seconds and were comparable with the onset of bolus doses of rocuronium and succinylcholine. In Phase II, good to excellent intubating conditions were obtained in 41% to 58% of patients included in Groups 1 through 5. Excellent to good intubating conditions were obtained in all patients (100%) who received succinylcholine. In Phase III, good to excellent intubating conditions were obtained in 91% of patients who received rocuronium-atracurium sequence. Symptoms of muscle weakness were not reported. Conclusions: Priming doses of rocuronium 0.1 mg/kg reduce the priming interval to 1 minute, allow early induction of anesthesia, eliminate patient discomfort, and accelerate the onset time of atracurium with intubating conditions comparable with succinylcholine and rocuronium.

Die Bestimmung der Atemfrequenz aus der respiratorischen Sinusarrhythmie (RSA). Determination of Respiratory Rate on the Basis of Respiratory Sinus Arrhythmia

In the clinical setting, the observation of undisturbed spontaneous respiration and direct measurement of an "unbiased" respiratory rate is not a practical option. However, the respiratory modulation of the heart rate (respiratory sinus arrhythmia, RSA) offers a possibility of recording the respiratory rate indirectly. The present work introduces a novel procedure for extracting the respiratory rate from the ECG, and compares the results thus obtained with those of a previously applied method. The latter is based on the determination of dominant peaks in the amplitude spectrum of a five-minute RR interval time series. The new method presented here is based on the band pass filtering of a one-minute RR interval time series with subsequent analysis of the maxima, minima and zero crossings of the resulting RSA curve. The methods were compared by determining the respiratory rates of 16 healthy male subjects measured in 15 different experimental situations, including spontaneous and controlled breathing. The respiratory rate as determined by thermistor recording of nasal breath temperature was used as control. The mean deviation from directly measured respiratory rate was 2.9 min-1 for the new and 7.2 min-1 for the previous method. The new method proved superior under all conditions except controlled breathing at low frequencies. The present study thus demonstrates the high precision of respiratory rate determined indirectly by analysing the RSA curve. Since it requires no special instrumentation, this procedure is ideally suited for clinical application, and permits the continuous recording of respiratory rate over long periods of time.

Within-session response patterns when rats press levers for water: Effects of component stimuli and experimental environment

Rats pressed levers for water reinforcers delivered by multiple variable interval one-minute variable interval one-minute schedules. Experiment 1 manipulated the stimuli signalling the components of the multiple schedule. Experiment 2 varied the experimental environment. Responding changed significantly within the session during every condition of both experiments. Manipulating the component stimuli significantly altered the within-session pattern of responding; varying the environment did not. These results show within-session patterns of responding occur when subjects respond for water reinforcers. They also imply that contextually-based explanations for within-sessions patterns of responding are unlikely.

The design and evaluation of an automated system for monitoring 133Xe in room air

The authors describe a system for continuous monitoring of the air concentration of 133Xe. The instrument consisted of a sodium iodide scintillation detector, a scalar/ratemeter and a data logger. The crystal was mounted inside a lead shield and enclosed in a perspex cylinder. A fan at one end of the cylinder drew room air into a shielded active volume via an inlet aperture designed to generate turbulent flow with no stagnant areas. The instrument was rendered relatively insensitive to external radiation by positioning the energy window over the 31 keV peak in the 133Xe spectrum. The detector sensitivity was approximately 2 s-1 per MBq m-3, with a typical background count rate of 0.12 s-1. The system was therefore capable of detecting a concentration of 0.06 MBq m-3 in a one-minute sampling interval.

Performance Analysis of a Wind-Assisted Heat Pump for a Dairy

ABSTRACT COMPUTER simulations based on measured component characteristics and site wind data predict the performance of a wind-assisted heat pump for a dairy. Farm residence space heating, water heating, and milk cooling are considered. A vertical axis Pinson C2E3 Cycloturbine is mechanically connected to a Carrier 5F30, 3-cylinder compressor with external cylinder loading/unloading capability. An electric motor powers the compressor during low wind conditions. Step-wise cylinder loading or unloading is used to load match the compressor with the cycloturbine torque at varying wind velocities. An insulated hot water reservoir and an ice-bank refrigeration milk cooler provide reserve energies. Simulation inputs include: (a) measured performance characteristics of the Pinson Cycloturbine and the Carrier compressor, (b) residential space heating and hot water requirements, (c) water heating and milk cooling requirements for a 50-cow dairy, and (d) nine months of one-minute interval wind velocity data from the wind turbine test site near Harford, NY. A description of the system and simulation results including dynamic effects are presented. System simulation results show a 41.6% reduction in the total electrical energy used for domestic heating, water heating, and milk cooling. However a major portion of this reduction was contributed by the heat pump since the wind turbine only provided an equivalent of 7.1% of the total energy used to drive the compressor on the heat pump.

On medium scale travelling ionospheric disturbances as seen through total electron content power spectra

Modulation phase of 140 MHz with respect to 360 MHz signals from ATS 6 satellite recorded at Slough (51.5°N, 0.6°W geographic latitude and longitude; 54.3° geomagnetic latitude) at one-minute interval are power spectral analysed to derive dominant periodicities corresponding to Travelling Ionospheric Disturbances. From the significant peaks in the spectra, an occurrence peak at periods between 10 and 15 min and a secondary peak at 60–65 min are seen. From cross-spectral analysis of the same records from three stations separated by a few hundred kilometers for a short period, the speed and azimuth of the propagating disturbances are determined. During the day-time, most of the waves in the period range 30–100 min are seen to propagate at azimuths of 90–160°. At night-time they propagate poleward. Theoretical computations of the azimuth response of TEC to typical gravity waves, including the effect of neutral winds, show that the observed azimuths of propagation are in reasonably good agreement with theoretical predictions.

Acquisition and extinction of a runway response after odor-intensified or -minimized conditions, within-subjects trial administration, and a one-minute intertrial interval.

A two-phase study was conducted during which 2 groups of albino rats received the same schedule of reward and nonreward, the same magnitude of reward and nonreward confinement, the same intertrial and intersubject intervals and the same trial order. The only difference was that one group of Ss was trained and extinguished under an odor-intensified condition, whereas the second group was trained and extinguished under an odor-reduced condition. In the goal segment Ss trained under an odor-intensified condition discriminated the schedule perfectly during acquisition and were less resistant to extinction than Ss trained under the odor-reduced condition. Following a 2-wk. interval, Phase II, the groups underwent acquisition and extinction again under reversed odor-conditions. The results were replicated within the study.