Power Watts Research Articles

Folding at home: Artificial intelligence and crypto symbiosis for the science

AbstractFolding at Home community gathers pecuniary crypto interest to an altruist cause (medical drugs research participation). There are many possibilities of ‘teams’ for folding, some of which allow compensation in cryptomonies. The authors will therefore study the three major communities in order to compare them, in a cost‐benefit study logic. A cost‐benefit analysis was performed between CURECOIN, BANANO, DOGECOIN folding, DOGECOIN mining and their communities on social platforms based on several outcomes: ‘Points Per Day (PPD)’, ‘Whattomine Mh/s Equivalent’, ‘Graphics Processing Units (GPU) Thermal Design Power/Typical Board Power Watts’, ‘Coins per 1,000,000 PPD’, ‘Coins per Day’, ‘Cost Per Coin’, ‘Cost Per Day’, ‘kWh Used Per Day’. Actually, BANANO, thanks to a large community and bots, has the highest PPD production and the lowest energetic cost on Central Processing Unit per week. On GPUs, DOGECOIN folding has the lowest weekly cost. However, the DOGECOIN community cannot produce as many PPD as the Banano team. CURECOIN offers a good compromise between the environmental point of view and the profitability one. To ensure fairness, the choice of the crypto and the way to earn it that has to be solved should be a pure public good, that is, perfectly non‐rival in consumption and non‐excludable. Indeed, the primary goal of those three communities is to allow scientific progress (thanks to Folding at Home) before allowing a return on investment.

The impact of using an IoT-based automatic solar panel cleaner on building energy performance

Abstract Solar energy is a great provider of renewable environmentally friendly energy. Thanks to solar technologies, it converts sunlight into electrical energy using multiple devices such as photovoltaic cells. The generated electrical energy can be used for multiple purposes such as commercial, industrial, and domestic uses. Generating electrical energy without releasing toxic gases is considered one of the biggest advantages of using solar energy. While solar panels are a reliable source of clean electrical energy, their power output can be decreased due to the lack of maintenance and especially cleaning. The efficiency of solar panels decreases by more than 40% due to the lack of cleaning. That is why routine cleaning is crucial to ensure the optimum performance of them. Providing an automatic solar panel cleaning system will ensure that routine maintenance is done and the electricity output is optimum. Integrating the use of photovoltaic cells in buildings helps improve the energy performance and energy efficiency of buildings. This research paper aims to determine the impact of integrating an internet of things (IoT)-based automatic solar panel cleaner and measure the energy efficiency of using it. The IoT-based automatic solar panel cleaner contributed to raising the solar panel power wattage by 89.33% in a hot desert climatic region.

Acute anodal transcranial direct current stimulation improves the performance of professional rowers.

The aim of the present study was to evaluate the influence of acute transcranial direct current stimulation (tDCS) on physical and subjective responses in professional rowing during the 2,000-m time trial test. Seven rowers (age 20.86 ± 4.49 years; weight 71.66 ± 7.97 kg) participated in this randomized triple-blind trial with a crossover experimental design. The protocol consists of 2 days with different conditions (anodal and sham). The tDCS anodic stimulation conducted was 2 mA for 20 min in the left temporal cortex (2.5 cm from the F7 zone and 2.5 cm from the T3 zone), targeting the left insular cortex. In the sham moment, the participants experienced 30 s of stimulation. Afterward, they performed a standardized progressive warm-up for 15 min, following the Brazilian Rowing Confederation's assessment protocols, and rested for 3 min before the test started. All procedures were made on an indoor rowing machine, which allowed the capture of performance variables such as time performed, power in watts (W), pace (m/min), and stroke rate (strokes/min). The ratings of perceived exertion [Borg scale (CR-20)] were recorded in each 2-min during the test. The results presented differences in power [Z: -2.371; p = 0.018; effect size (ES) = -0.896 (large)] and pace [Z: -2.371; p = 0.018; ES = -0.896 (large)] and time performance [Z: -1.612; p = 0.107; ES = -0.609 (large)] throughout the protocol for the anodal moment. However, no differences for the other variables were found. According to the results, the current tDCS with the present protocol improved the physical performance at the 2,000-m time trial Test providing ergogenic aid.

Impact of Circuit Power on the Energy Efficiency of Massive Multiple-Input Multiple-Output (MIMO) Cellular Systems

Massive multiple-input multiple-output (MIMO) systems are designed to increase data capacity systems. However, there are growing social and economic concerns in developing these communication technologies. Energy efficient systems are desirable for these systems considering the costs and minimizing resources. Thus, the optimization of these approaches is significant in the advancement of green communication. This paper converges on the circuit power in modelling massive MIMO systems. Specifically, to apply various power consumption of the transceiver chains, to determine the desired power of the base station value for maximum energy efficiency, and to define the effects of a realistic circuit power consumption model in Massive MIMO systems. Mathematical models were developed, and the corresponding codes were simulated using MATLAB. Different processing schemes were also studied, namely, maximum ratio transmission/maximum ratio combining, and zero forcing for the perfect and imperfect single-cells scenario. In contrast, multiple cells consider different re-use factors. As observed, a low power wattage consumption of transceiver chains and base stations is desired to produce a more remarkable relative change in energy efficiency. Local oscillators' power usage is also recommended to be low wattage. Low-power systems utilize low energy consumption but not disregarding higher energy efficiency. Other factors in data throughput – bandwidth, transmit power, noise power spectral density, and path loss, can be studied to optimize energy-efficient massive MIMO systems.

Energy Performance Benchmarking in University of Lagos Hostel Buildings

Expenditure on energy accounts for up to 35% of the overall annual operational budget for most buildings. Top management of Nigerian public universities are saddled with the responsibility of reducing operational costs and optimizing resources as a strategic response to the global economic crisis and reduced government funding in the face of rising energy demand in the universities. The study benchmarked the energy performance of the University of Lagos hostel buildings. Through a cross-sectional survey, questionnaire administration and energy audit of 130 student hostel rooms at the University of Lagos were conducted. The study assessed the power ratings and duration of use of the appliances and gadgets in each of the hostel rooms. The data collected were analysed using descriptive and inferential statistical tools comprising frequency tables, bar chart, sum of scores, correlation and ANOVA analysis respectively. The results indicate the Building Energy Performance Index of the hostels is 372.11 kWh/m2/year which significantly exceeds the benchmark for hostel buildings. Electric hot plates, pressing irons and fans are the topmost energy-consuming appliances across the student hostels. The study concludes that the energy performance of the student hostel is poor and recommends that the University of Lagos management should define power wattage threshold for appliances to be used by students in the hostels as a major active energy optimization strategy.

Arduino Base Multimeter

The main objective of this project is to build an Arduino nano based All in one multimeter, a device that can be used to measure the voltage, current and the power consumed by a load. There are number of ways that you can implement the Arduino nano based all in one multimeter Project. One of the easy ways is to interface a Voltage Sensor and a Current Sensor with Arduino, measure the voltage and current values and finally with some mathematics, you can calculate the Power in Watts. The Sensor Part of the circuit is responsible for measuring the Voltage across the load and Current through the load. Both these values, which are analog in nature, are given to the Arduino to its ADC. Arduino converts these values to digital values and makes a few calculations as displays the results on the LCD.

Reliability, Validity and Minimal Detectable Change of a Power Leg Press Test in Individuals with Cerebral Palsy

Background Lower extremity muscle power influences walking ability in individuals with Cerebral Palsy (CP). Aim Determine the reliability, validity, and minimal detectable change (MDC) of a novel power leg press (PLP) test to measure muscle power in individuals with CP. Methods Individuals with spastic CP (n = 26 (10 adults, 16 children); mean (SD) age = 19.3 (7.8) years(all); 27.9 (4.89) years (adults); 13.85(2.68) years (children)) performed 2 sessions of the PLP test, 2–10 days apart. A linear position transducer and custom computer code were used to calculate mean and peak power in watts (W). Intraclass correlation coefficients (ICC), standard error of measurement, MDC, and percent change of MDC (MDC%) were calculated for 4 power measures (average and maximum of mean and peak powers) for all participants (AP) and separately for adults (A) and children (C). Validity was evaluated against isokinetic knee extensor power. Results Test-retest reliability was excellent for all measures of power (ICC = 0.94–0.99). Ranges for MDC/MDC% by the group for power measures were between 33.7–80.7W/15.5–29.4% (AP), 41.1–65.3W/10.7–22.3% (A), and 27.6–79.8W/19–34.3% (C). Correlations were good to excellent between PLP and isokinetic power at all speeds (r = 0.75–0.88, p < .001). Conclusions The PLP test demonstrates excellent validity, reliability, and precision for measuring muscle power in those with CP.

Relationships Between Lower Extremity Power and Fastball Spin Rate and Ball Velocity in Professional Baseball Pitchers.

Wong, R, Laudner, K, Amonette, W, Vazquez, J, Evans, D, and Meister, K. Relationships between lower extremity power and fastball spin rate and ball velocity in professional baseball pitchers. J Strength Cond Res 37(4): 823-828, 2023-Lower extremity power has been hypothesized to increase ball spin and velocity during pitching in baseball. Therefore, the purpose of this study was to determine the relationship between lower extremity power and fastball spin rate in professional baseball pitchers. A secondary purpose was to determine the relationship between lower extremity power and ball velocity. Fifty-three asymptomatic professional pitchers participated (24.5 ± 3.6 years; 189.9 ± 6.1 cm; 92.6 ± 10.3 kg). Each athlete performed 3 separate bilateral jump tests on force plates: countermovement jump (CMJ), squat jump (SJ), and drop jump (DJ). The average fastball spin rate and ball velocity for each pitcher was calculated using a 3-dimensional Doppler radar and video system over the course of a competitive season. Standard multiple regression analyses ( p ≤ 0.05) revealed significant relationship between ball spin and summation of variables for the CMJ (peak force, peak power, rate of power development, and jump height) ( R2 = 0.20, F = 3.1, p = 0.03). However, no individual variable was significantly associated ( p > 0.09). There was also a significant amount of variance in ball spin explained by summation of variables for the SJ (peak force, peak power, rate of power development, and jump height) ( R2 = 0.19, F = 2.8, p = 0.04); rate of power development was the only variable that significantly predicted ball spin within this model ( B = 0.27; 95% confidence interval [CI]: 0.003-0.75, p = 0.05). Ball spin was not associated with summation of DJ variables (peak power, rate of power development, jump height, reactive strength index, and total peak power in watts) ( R2 = 0.18, F = 2.0, p = 0.09). For ball velocity, there were no significant relationships for the summation of either the CMJ variables ( R2 = 0.10, p = 0.28) or the SJ variables ( R2 = 0.07, p = 0.44). However, there was a significant amount of variance in ball velocity explained by summation of variables for the DJ ( R2 = 0.30, F = 3.93, p = 0.005). The reactive strength index was the sole unique contribution to this model ( B = 1.18; 95% CI: -10.34 to 2.36, p = 0.002). These findings highlight the relevance of increased lower extremity power on increasing fastball spin rate and ball velocity.

INFLUENCE OF 50 METER DRILL OF DIFFERENT INTENSITY TRAINING ON ANAEROBIC CAPACITY OF MALEKHO-KHO PLAYERS

Purpose: Aim of the study was to investigate the influence of 50 meter drill of different intensity training on anaerobic capacity of male Kho-Kho players. Method: Pre test - Post test Purposive Design was used by which total thirty two (N=32) male Kho-Kho players (Age: 17.66 + 1.34 years, BMI: 20.04 + 1.36 kg/m2, Resting Heart Rate: 74.44 + 1.44 beats/min., Training Age: 3.78 + 0.75 years) were purposively selected and assigned into four equal groups: HIITG (n=8), MIITG (n=8), CHMIITG (n=8) and ACG (n=8). Anaerobic Capacity (Unit: Watts) was assessed by Running Based Anaerobic Sprint Test (RAST) before and after the completion of eight weeks 50 meters drill of different intensity interval training. Data analysis methods were descriptive statistics: Mean, Standard Deviation and Standard Error, inferential statistics: 2-tailed One-Way ANCOVA with Bonferroni Post-Hoc test and normality test: Shapiro-Wilk test respectively performed on IBM SPSS software (Version: 25). The alpha (α) level was set at p≤0.05 for significance, whereas the effect size was reported with the 95% confidence for all analyzed measures. Result:The results shown that there was significant (p&lt;0.05) increases in anaerobic capacity (Power in Watts) for each experimental groups (EG) in comparison to active control group (ACG). Conclusion:The present results indicate that eight (8) weeks 50 meter drill of different intensity interval training showed an increase in anaerobic capacity of senior state level male Kho-Kho players. Not only HIIT is better and beneficial than MIIT, but also CHMIIT too is better and beneficial than MIIT.

Compression of Deep Learning Models for Text: A Survey

In recent years, the fields of natural language processing (NLP) and information retrieval (IR) have made tremendous progress thanks to deep learning models like Recurrent Neural Networks (RNNs), Gated Recurrent Units (GRUs) and Long Short-Term Memory (LSTMs) networks, and Transformer [ 121 ] based models like Bidirectional Encoder Representations from Transformers (BERT) [ 24 ], Generative Pre-training Transformer (GPT-2) [ 95 ], Multi-task Deep Neural Network (MT-DNN) [ 74 ], Extra-Long Network (XLNet) [ 135 ], Text-to-text transfer transformer (T5) [ 96 ], T-NLG [ 99 ], and GShard [ 64 ]. But these models are humongous in size. On the other hand, real-world applications demand small model size, low response times, and low computational power wattage. In this survey, we discuss six different types of methods (Pruning, Quantization, Knowledge Distillation (KD), Parameter Sharing, Tensor Decomposition, and Sub-quadratic Transformer-based methods) for compression of such models to enable their deployment in real industry NLP projects. Given the critical need of building applications with efficient and small models, and the large amount of recently published work in this area, we believe that this survey organizes the plethora of work done by the “deep learning for NLP” community in the past few years and presents it as a coherent story.

Abstract 12450: Inflammatory Gene Expression Changes and Immune System Depression in Rats Exposed to a Single 4-hr Exposure to Electronic Cigarette Vapor

Introduction: lectronic cigarette (eC) or Vaping induced Lung Injury (EVALI) was first described in the summer of 2019 in patients presenting with acute respiratory distress. Several factors contributing to EVALI are suspected, including use of oil carriers, and heating and power elements. This study examined whether a single acute exposure to eC smoke using two popular heating elements on high or low power levels would induce inflammatory gene expression and proteins, and changes in alveolar macrophage function. Hypothesis: We hypothesize that nichrome, but not stainless-steel atomizers and high power wattage used in the eC device contribute to the extent of changes in pulmonary inflammatory response and alveolar macrophage activity. Methods: Adult Sprague Dawley rats were exposed to clean air (n=8) or eC vapor (50% propylene glycol, 50% vegetable glycerin, tobacco flavoring, no nicotine, n=8) for a single four hour period using devices equipped with stainless steel (SS) or nichrome (NC) heating elements at 45 or 70 wattage power (5 exposure conditions per sex group). Rats were euthanized and bronchoalveolar lavage was performed to collect alveolar macrophages for ex-vivo cell studies. The remaining lung tissue was homogenized for inflammatory protein and gene expression analyses. Results: Significant changes were observed in animals assigned to 70 watts. Increases ranging from 1.5-fold to 2-fold change in expression of the inflammation related genes IL-6, TNF-α and CRP occurred in rats assigned to NC atomizers (p ≤ 0.05), predominantly in males. While the concentration of CRP protein was significantly increased in females, CRP gene expression was decreased at the time point examined. Other proteins were not significantly elevated. Significant (p ≤ 0.05) changes in phagocytic activity were only observed in males exposed to 70 watts NC vapor, which generated exaggerated superoxide production by 4-fold during ex-vivo incubation. Evidence of depressed phagocytic activity was observed in other exposure groups, although not statistically significant. Conclusions: These results demonstrate that a single 4-hr exposure to e-cigarettes can initiate increased gene expression of inflammatory markers IL-6, TNF-α and CRP and oxidative changes in the lung.

Diode laser and desensitizing agent team up against dentinal hypersenstivity: Will this duo succeed?

INTRODUCTION: Dentinal hypersensitivity (DH) is a chronic disorder in which patients report sharp and acute pain to a variety of stimuli, that occurs when the dentin is exposed. Patients with DH, tend to change their daily habits leading to changes in their way of life so it is important to highlight the treatment of DH by several alternative including laser therapies, desensitizing agents etc. AIM: To study the effect of clinical application of diode laser (810 nm) in comparison with a desensitizer (5% KNO3) in the treatment of dentin hypersensitivity. MATERIAL AND METHODS: The study population comprising of 60 patients with 120 teeth assigned into 3 groups. Group I: treated with 5% KNO3 for 60 sec, using a disposable brush and restrained to rinse until 3 min. Group II: Lased with diode laser (810 nm) in non contact mode with a fiber tip for 60 sec. using a power wattage from 1 – 2 watts kept at a distance of 10 – 20 cm from the surface of tooth. Group III: Treated with both 5% KNO3 and diode laser for 60 sec. After cleaning, drying and isolating the tooth patients‘s response was checked using a visual analogue scale (VAS) both before and after e treatment and at the follow ups of 15 min, 2 and 4 weeks. STATISTICAL ANALYSIS: An independent paired t test was used to evaluate the periodontal clinical parameters and VAS. RESULTS AND CONCLUSION: Synergism of diode laser and KNO3 together, showed the best results than their individual application. KEYWORDS: Diode laser (810nm), dentinal hypersensitivity, 5% KNO3

Magnetic Hyperthermia in the 400–1,100 kHz Frequency Range Using MIONs of Condensed Colloidal Nanocrystal Clusters

In the current study, we explored the magnetic hyperthermia performance of condensed–clustered magnetic iron oxide nanoparticles (MIONs) in the range of 400 kHz to 1.1 MHz at low field amplitudes. The strong interparticle interactions, present in such systems, can influence the hyperthermia power produced by MIONs. Herein, the heat dependence, as an increasing function of frequency, with a fixed magnetic field strength of 3 mT is recorded, revealing a direct relationship between the two physical quantities and a high heating efficiency for the condensed–clustered MIONs. In particular, the specific loss power (SLP) (or specific absorption rate [SAR]) parameter, which is the ratio of the heat power in watts produced per nanoparticle mass in grams, is linear to a good degree to the oscillating frequency with a step of roughly 30 W/g per 100 kHz increase. In addition, all the measurements were within the safety limits proposed by Hergt and Dutz criterion of H f ≤ 5 × 109A/ms for clinical application of magnetic fluid hyperthermia (MFH). Finally, the measured data of temperature vs. time at each frequency were interpreted in terms of simple thermodynamic arguments, thus extracting useful thermodynamic parameters for the heat power generated by the condensed–clustered MIONs.

A Tale of Two Entities

With the growing market of Electric Vehicles (EV), the procurement of their charging infrastructure plays a crucial role in their adoption. Within the revolution of Internet of Things, the EV charging infrastructure is getting on board with the introduction of smart Electric Vehicle Charging Stations (EVCS), a myriad set of communication protocols, and different entities. We provide in this article an overview of this infrastructure detailing the participating entities and the communication protocols. Further, we contextualize the current deployment of EVCSs through the use of available public data. In the light of such a survey, we identify two key concerns, the lack of standardization and multiple points of failures, which renders the current deployment of EV charging infrastructure vulnerable to an array of different attacks. Moreover, we propose a novel attack scenario that exploits the unique characteristics of the EVCSs and their protocol (such as high power wattage and support for reverse power flow) to cause disturbances to the power grid. We investigate three different attack variations; sudden surge in power demand, sudden surge in power supply, and a switching attack. To support our claims, we showcase using a real-world example how an adversary can compromise an EVCS and create a traffic bottleneck by tampering with the charging schedules of EVs. Further, we perform a simulation-based study of the impact of our proposed attack variations on the WSCC 9 bus system. Our simulations show that an adversary can cause devastating effects on the power grid, which might result in blackout and cascading failure by comprising a small number of EVCSs.

Development of portable device for measurement of dynamic and static light-emission WOLED characteristics

The research object of this work is the parameters of organic light-emitting diodes, namely power and luminous flux. Determination of these parameters can be carried out using a photodiode and requires measuring the dark current of the sensor (photodiode), measuring the current of the photodiode when illuminated by the LED under investigation. And also take into account the relationship between the light flux received by the sensor and its output current, and take into account the spectral characteristics of the sensor. Calculate the investigated parameters of the LED based on the measurements. Carrying out these measurements requires laboratory instruments and workplace organization, and further calculations are routine work. It is possible to increase the measurement accuracy by improving the existing methods for measuring the required parameters, and it is possible to automate the process of measurements and calculations using a modern microprocessor radioelement base. Microcontrollers are widespread such radioelements. They have the necessary peripherals for independent operation and have sufficient computing power to implement the required measuring device. Its application makes it possible to automate the measurement process, carry out the necessary calculations, save correction constants, accumulate and process the obtained data, analyze these received data, exchange data with a computer, etc. So, the work is aimed at developing a methodology that will allow the simultaneous measurement of power and luminous flux of planar light sources. And also on the feasibility of this technique in the device and software with the ability to measure the power of the light source in an arbitrary band of the spectral visible range. Thus, it is possible to determine what power in watts a light source emits with the dynamics of supply currents in the optical bands, knowing the spectrum of this source without using glass filters. So, the result of applying the technique is to determine the power of light radiation (in watts) or the luminous flux (in lumens) of the emitter (light sources).

Comparison Of Warm-Up Strategies On Internal And External Rotation Mechanics In Collegiate Pitchers

Rotator cuff strains are the most common musculoskeletal injury in collegiate baseball pitchers. A variety of warm-up routines are employed, the effects of these routines on the subsequent function of the rotator cuff lack comparison. PURPOSE: To test the effect of four different warm-up routines on internal (IR) and external rotation (ER) shoulder kinematics. METHODS: Seven D1 collegiate pitchers were enrolled in an experiment involving four testing sessions. Each session began with one of four warm-up protocols: 1) Jaeger bands (JB), 2) standard dynamic warm-up (DW), 3) Jaeger bands and standard dynamic warm-up (JBDW), or 4) dynamic warm-up using collinear resistance (CR). Immediately after the warm-up, athletes underwent biomechanical analysis of internal and external shoulder rotation using Proteus (Proteus Motion, USA). They performed 12 repetitions of each motion using 5lb of 3D magnetic resistance. 48 hours of rest separated each session. The assigned sequence of protocols was counter-balanced. Proteus software computed peak power in watts (w), peak force development rate in watts/second, range of motion in meters (ROM), consistency (the ability to replicate ROM in three-dimensional space), and endurance (replication of power parameters in successive repetitions). A one-way repeated measures ANOVA was used. RESULTS: Subjects were 20.4±1.4 years of age. Across all conditions, peak power was 96.3±13.7 w in IR and 99.3±15.7 w in ER; peak force development rate was 387.7±118.5 w/sec in IR, and 418.7±195.6 w/sec in ER. Differences were detected in the four warm-up conditions in peak power (CR highest; p=0.015), peak force development rate (CR highest; p=0.072), and ROM (CR highest; p=0.015). No difference was found in deceleration (p=0.336), consistency (p=0.903), or endurance (p=0.769). External rotation was different in the four warm-up conditions in peak force development rate (CR highest; p=0.045). No statistical difference was found in power (CR was highest, but did not reach significance; p=0.104), deceleration (p=0.520), consistency (p=0.478), endurance (p=0.145), or ROM (p=0.543). CONCLUSION: The simulated dynamic warm-up using three-dimensional resistance elicited the best subsequent function, follow up studies should examine mechanisms that produce this difference.

Hematological, Hormonal and Fitness Indices in Youth Swimmers: Gender-Related Comparisons.

This study objective was to evaluate gender differences in hematological, hormonal and fitness variables among youth swimmers and to explore relationships between erythrocyte indices and aerobic and anaerobic capacity. 137 girls and 171 boys participated in the study and were divided into three groups based on their training experience. Blood samples were obtained to determine red blood cell counts, hemoglobin concentration, hematocrit, and plasma erythropoietin and testosterone levels. VO2max was assessed using a submaximal cycle protocol. 76 girls and 102 boys also undertook a Wingate test to determine their peak anaerobic power. Boys had higher (p < 0.05) means than girls for all hematological variables except for erythropoietin and these variables demonstrated an increase with training in boys. The average VO2max in l∙min-1 and peak anaerobic power in watts were also higher in boys (2.91 ± 0.08 and 547 ± 28, respectively) than girls (2.25 ± 0.07 and 450 ± 26, respectively). Modest but significant (p < 0.05) correlations were found between VO2max and red blood cell counts (r = 0.252), hemoglobin concentration (r = 0.345), or hematocrit (r = 0.345) and between peak anaerobic power and red blood cell counts (r = 0.304), hemoglobin concentration (r = 0.319) or hematocrit (r = 0.351). This study revealed relatively lower yet age- and gender-appropriate hematological, hormonal and fitness indices in youth swimmers. The gender-related differences in erythrocyte indices seem unrelated to erythropoietin and may be explained by the higher testosterone levels seen in boys. Given their correlation to both aerobic and anaerobic capacity, erythrocyte indices may be used as part of talent identification for sports.

Relationships Between Absolute and Relative Strength and Power in Male Police Officers of Varying Strength Levels

Strength and power are important traits for law enforcement officers, but the relationship between these measures has yet to be determined in a law enforcement population. Furthermore, the nature for these relationships between officers of varying strength is not known. The purpose of this study was to investigate the relationship between strength and measures of power and to determine whether stronger officers portrayed greater power. Retrospective data for 543 male (age = 39.07 ± 8.04 years; height = 180.02 ± 15.14 cm; body mass = 92.73 ± 16.37 kg) officers from one agency were provided. Measures included isometric leg/back dynamometer (LBD) strength, a counter movement jump (CMJ) and further determined measures of lower body power [estimated anaerobic power in watts (PAPw)] and power to body mass ration (P:BM). Following an analysis by cohort, subgroup quartiles were created based off LBD strength [absolute (LBDa) and relative (LBDr)]. The strongest quartile (Q1) performed significantly better in CMJ and PAPw than the other groups, but not in P:BM. Significant (P ≤ 0.001) low-to-moderate positive correlations were found between LBDa and CMJ height (r = 0.388), PAPw (r = 0.606) and P:BM (r = 0.272) and between LBDr and CMJ (r = 0.556), P:BM (r = 0.642) and PAPw (r = 0.149). Only LBDr was significantly related to all power measures across all sub groups. The development of relative lower body strength may best prepare officers for power assessments (such as vertical jump assessments) as well as for occupational tasks that require power.

Body composition, physical fitness, physical activity and nutrition in Polish and Spanish female students of sports sciences

Summary Objectives It is important to study differences in body composition, physical fitness and lifestyle behaviours between university students from different countries to develop country-specific recommendations on health promotion to provide to students when transitioning to university. The objective of this study was to analyze the differences in body composition, physical fitness and lifestyle between Polish and Spanish students of physical activity and sports sciences. Equipment and methods Two hundred and thirty female students participated. One hundred and eighty-eight females were from Poland and 42 females from Spain. Polish females were 21.2 ± 1.9 yr old and Spanish females 21.1 ± 2.2. The body composition variables measured were: body weight (kg), fat-free mass (FFM, kg and %), fat mass (FM, kg and %), total body water (TBW, kg and %), and basal metabolic rate (BMR, kcal), body mass index (BMI, kg/m2), fat-free mass index (FFMI, kg/m2), fat mass index (FMI, kg/m2). The physical fitness variables measured were: squat jump (SJ, height in cm, power in watts and w/kg), counter movement jump (CMJ, height in cm, power in watts and w/kg), running speed 10, 20, 30 m (time in s), progressive aerobic cardiovascular endurance run (PACER, stage, final speed in km/h, distance in m, VO2max in ml/kg/min). Lifestyle variables measured were: vigorous physical activity (VPA, days/week, min/week), moderate physical activity (MPA, days/week, min/week), walking (days/week, min/week), sitting (min/week), meals/day, vegetables/day, fruits/day, seafood/week, dairy products/week, sweets, chips, fast food/week, litres of liquid/day, litres of sugary drinks/day, alcohol/week, and cigarettes/day. Results Polish females had more favourable profiles than Spanish females for body composition and physical fitness, and consumed more vegetables, more fruits and more liquids. Spanish females did more physical activity, consumed more seafood, more dairy products, less sweets, chips, fast food, less sugary drinks, less alcohol and less tobacco than Polish females. Conclusions Curricula should be adapted, in Poland to promote a healthier lifestyle and in Spain to improve body composition and physical fitness.

Test-retest reliability of a maximal arm cycle exercise test for younger individuals with traumatic lower limb amputations

Study design: Cross-sectional study design.Background: Cardiopulmonary exercise testing (CPET) using the upper-body is an alternative to standardised CPET. A variety of test protocols has been developed for CPET performed on an arm crank for individuals with lower limb disabilities. However, no test protocol specifically designed to evaluate exercise capacity in younger adults with lower limb amputees is available.Objective: To determine test–retest reliability of VO2peak, watts, test time and max heart rate for an upper-body CPET.Methods: Males with unilateral lower limb amputation at crus-level or above, aged 18–40 years, without comorbidities preventing arm cycling were eligible. Participants completed three maximal tests with a minimum of two days between tests and maximum 14 days between the first and third test.Results: Eight participants volunteered to participate and were tested three times. Excellent and acceptable ICC values were found for power in Watts (ICC = 0.73) and test time (ICC = 0.74). Good but non-acceptable test–retest reliability was found for VO2peak (ICC = 0.51) and max heart rate (ICC = 0.64) for all three test sessions.Conclusions: Upper-body CPET shows acceptable test–retest reliability for Watts and test time in younger adult lower limb amputees, but non-acceptable reliability for VO2peak and heart rate.