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Background & aims Severe acute COVID-19 has taken on pandemic proportions with growing interest in identification of prognostic factors for mortality. Standardized bioelectrical impedance (BI) phase angle (SPhA), which is PhA adjusted by age and sex, has been related to mortality in patients with several diseases but never investigated in COVID-19. Inflammation, a consequence of COVID-19 infection, affects fluid status (hydration) and can be identified with PhA. The aim of this study was to determine the predictive role of PhA on 90 days survival of adults with COVID-19. Methods We studied 127 consecutive patients diagnosed with COVID-19. BI measurements determined with a 50 kHz phase-sensitive BI device, body composition parameters and laboratory markers were evaluated as predictors of mortality. Results Non-surviving COVID-19 patients had significantly lower PhA and SPhA values (p

Background Methods that facilitate muscle quality measurement may improve the diagnosis of sarcopenia. Current research has focused on the phase angle (PhA) obtained through bioelectrical impedance analysis (BIA) as an indicator of cellular health, particularly cell membrane integrity and cell function. The current study therefore aimed to evaluate the relationship between the PhA and muscle quality and muscle‐related parameters and to determine factors associated with the PhA. Moreover, we attempted to determine the cut‐off value of PhA for predicting sarcopenia. Methods First‐year university students (830 male students, 18.5 ± 0.6 years old; 422 female students, 18.3 ± 0.5 years old) and community‐dwelling elderly individuals (70 male individuals, 74.4 ± 5.5 years old; 97 female individuals, 73.1 ± 6.4 years old) were included. PhA and other body composition data were measured using BIA, while muscle quality was calculated by dividing handgrip strength by upper limbs muscle mass. The relationship between PhA and the aforementioned parameters were then analysed, after which the cut‐off value of PhA for predicting sarcopenia was examined. Results Multiple linear regression analysis revealed that age, skeletal muscle mass index (SMI), and muscle quality were independently associated with PhA in both sexes [male (age: standardized regression coefficient (β) = −0.43, P

The balanced, unbalanced and harmonic current sharing inaccuracy caused by the mismatched wire impedances of distributed generation (DG) units influences the normal operation of islanded microgrids. To deal with this issue, an iterative virtual impedance regulation (IVIR) strategy is proposed in this paper, both the resistive and reactive parts in the output impedances of DG units are regulated. The whole process is decomposed into several successive iterations. In each iteration, the fixed virtual impedance and adaptive virtual impedance regulation are combined to generate a virtual resistance increment and uniform virtual reactance increment according to the uniform output current magnitude and phase angle respectively. Based on these increments, the virtual impedance at fundamental-negative and harmonic frequencies also are modified. With the proposed strategy, all the balanced, unbalanced and harmonic current sharing is accurate with a relatively small virtual impedance. Only the local current information is required for the IVIR process, and the communication is merely used to exchange the VIR mode status flags at the beginning and the end of the IVIR process, the dependency on communication is minimized. The feasibility of the proposed strategy is verified with the simulation and experimental results.

Rationale: The progressive decline in skeletal muscle strength and function during aging can lead to disability and premature death. It is of interest to evaluate the potential of bioimpedance phase angle (PhA) as an instrumental marker of sarcopenia in clinical practice.Aim: To identify an association between the phase angles determined by the bioimpedance analysis of body composition, with functional activity parameters in elderly women with multiple comorbidities.Materials and methods: The study included 146 elderly women (aged 75 to 84 years, mean age 79.44 ± 2.56 years). Assessments consisted of the Charlson comorbidity index, “Vozrast ne pomekha” (Age is not a hindrance) questionnaire, the Barthel index, the sit-to-stand five-repeat test, the standardized 4-meter walking speed test, and bioimpedance analysis of body composition (ABC-02, Medass, Russia). Muscle strength parameters were assessed by wrist dynamometry with a mechanical wrist dynamometer. The hand dynamometry index was calculated by dividing the hand grip strength by the patient's squared height. According to the EWGSOP2 guidelines for the critical cur-off for hand dynamometry, the patients were divided into two groups: those with the hand grip strength > 16 kg (n = 41) and those with < 16 kg (n = 105).Results: There were significant correlations of PhA with age (r = -0.369; p =0.017), the results of the screening questionnaire “Vozrast ne pome-kha” (Age is not a hindrance) (r = -0.359; p = 0.023), Barthel index (r = 0.375; p = 0.018), hand dynamometry (r = 0.395; p = 0.014), hand dynamometry index (r = 0.340; p = 0.021), lean body mass (r = 0.414; p = 0.009), musculoskeletal mass (r = 0.819; p < 0.001), proportion of musculoskeletal mass (r = 0.796; p < 0.001), walking speed (r = 0.670; p < 0.001), and the results of the sit-to-stand test (r = -0.541; p < 0.001). Sarcopenia was diagnosed in 61 women (41.8%). There were also significant differences in age, hand dynamometry results, hand dynamometry index, walking speed and results of the sit-to-stand test between the two groups depending on their hand grip strength.Conclusion: The use of hand dynamometry, physical activity tests, and bioimpedance phase angle can be used in clinical practice to diagnose sarcopenia.

Distributed Generators (DGs) are incorporated in the power distribution systems to develop green energies in microgrids. Islanding is a challenging task in a microgrid. Different types of islanding methods, e.g. local and remote methods, have been developed for handling this task, with local methods being easier to implement, while remote methods are communication-based and costly. The local methods are classified as passive, active, and hybrid, out of which the passive methods are more simple and economical. In this paper, a passive islanding detection method is proposed to detect single line to ground fault. This fault is considered to represent the 60 to 70% of the total un-intentional faults of this category. The available passive methods cannot detect islanding at lower power mismatches as the variations in voltage and frequency fall within thresholding values. In this method, the voltage signals are first retrieved at the targeted DG output and then the phase angle is estimated. Finally, the phase angle is differentiated to get Rate Of Change Of Voltage Phase Angle (ROCOVPA) to detect islanding, and then it is compared with the Rate Of Change Of Frequency (ROCOF) at zero percent power mismatch. Simulation results depict that the ROCOVPA is more effective than ROCOF. The proposed method not only reduces detection time and Non-Detection Zone (NDZ) but is also stable during non-islanding cases like load connection and disconnection to avoid nuisance tripping.

OBJECTIVE To evaluate the role of PhA in diabetes in a large population of older adults with a high prevalence of diabetes in order to gain new insights on the potential diagnostic and prognostic role of PhA in individuals with diabetes. DESIGN Cross-sectional study. SETTING Teaching Hospital. PARTICIPANTS 1085 individuals aged 55 years or over. MEASUREMENTS Phase Angle was obtained using bioimpedance analysis with the Bodystat QuadScan® 4000. Diabetes mellitus was considered present with fasting hyperglycaemia (serum fasting glucose >6.66 mmol/l), HbA1c > 42 mmol/mol (6.1%), or self-reported Diabetes or the consumption of glucose-lowering agents. RESULTS The mean age of the (standard deviation) of the 1,085 participants was 68.11 (7.12) years and 60.7% were women. Among male participants, individuals with PhA within the lowest quartile (PhA ≤4.9) were significantly more likely to have diabetes mellitus [odds Ratio (95% confidence interval, CI), 2.02 (1.17-3.47)] following adjustments for age, body mass index and other comorbidities. The above relationship was attenuated following further adjustment hypoglycaemic medications. Men on oral hypoglycaemic agents had significantly reduced PhA [mean difference (95% CI), -0.44 (-0.67 to -0.22)]. No significant relationship between PhA and diabetes existed among women. CONCLUSION The association between lower PhA (≤4.9) in men aged 55 and over and diabetes which is accounted for by oral hypoglycaemic agents. The mechanisms underlying this relationship remain unclear. This relationship should also be evaluated further to determine the potential of PhA as a prognostic tool for diabetes.

Background Few studies have evaluated the prevalence of post‐extubation dysphagia and associated factors in patients with coronavirus disease 2019 (COVID‐19) . Our study assessed the prevalence of post‐extubation dysphagia and body composition in patients with COVID‐19 discharged from an intensive care unit (ICU). Methods A prospective cohort study was performed in post‐ICU extubated patients with acute respiratory distress syndrome related to COVID‐19 in two referral hospitals. A total of 112 patients were evaluated and included; swallowing assessment and bioelectrical impedance analysis (BIA) were performed after extubation and discharge from the ICU. To identify associations between dysphagia, lower phase angle (PhA) (

Single- and multifrequency bioelectrical impedance analysis (BIA) has gained popularity as a tool to assess body composition and health status of children and adolescents, but many questions and misconceptions remain. This review addresses pressing issues researchers and health care providers may encounter when using BIA in the young population. The importance of choosing population-specific and device-specific equations to estimate body composition as well as the use of BIA in longitudinal analyses are discussed. When specific equations are not available, raw bioimpedance values (i.e., resistance, reactance, and impedance) can be used to compute bioimpedance parameters, such as phase angle, impedance ratio, and bioelectrical impedance vector analysis. As interpreting these parameters is challenging, suggestions are provided on the use of reference data, cut-off points, and adjustment factors. Furthermore, unsolved technical and analytical issues are listed. Based on existing issues and potential for future development, a greater interaction between industry and academic researchers to improve the validity of BIA measurements among children and adolescents across their developmental stages is encouraged.

The present study proposes a practical yet reliable model for stay cables in cable-stayed bridges considering large force variation under seismic actions. The proposed model is capable of approximating the nonlinear equivalent stress-strain relationship of cables, taking into account the variation of equivalent modulus of cables during the earthquake as well as possible cable loosening. The cable performance based on the proposed method shows an overall good agreement with the actual response of cables. Then, the model is applied to a case cable-stayed bridge under seismic actions and the structural response is compared with the conventional method which models the cables with a constant equivalent modulus derived at dead load state. Comparing to the proposed model, the conventional method fails to accurately describe the cable force at the low stress level and shows discrepancies in time histories of the structural response in terms of amplitude and phase angle. Moreover, conventional method might lead to underestimation of the bending moment at the tower bottom and longitudinal displacement at deck end for most cases, resulting in unconservative seismic design. Such result highlights the importance of applying the proposed model in seismic design of cable-stayed bridges.

Summary Background & aims Bioimpedance analysis-derived phase angle (PhA), as marker of body cell mass and cell integrity, might be altered in obesity, a condition which is characterized by alterations in muscle structure and function. The aim of this systematic review was to evaluate whether and to which extent PhA varies in individuals/patients with excess body weight focusing on: a) changes in PhA due to obesity; b) changes in PhA after bariatric interventions or training programs. Methods According to PRISMA criteria, a systematic literature search until February 2021 using PubMed, Embase, Scopus, and Web of Science was performed. Selection criteria included studies on patients with obesity without comorbidities other than metabolic diseases. Results A total of 278 articles were first identified. After removing duplicates and excluding studies that did not fulfil the inclusion criteria, the full text of the remaining 80 potentially relevant studies was examined to finally retrieve 11 cross-sectional and 10 longitudinal studies. Few studies have shown that PhA is lower in individuals/patients with obesity than in controls. The only study on the matter showed a decrease with age after the fourth decade of life. Four out of five studies reported consistently greater mean values in men than in women. In two studies PhA was lower in patients with severe obesity; in addition, Patients with low PhA had higher BMI and PhA was inversely correlated with fat mass. Longitudinal studies showed that PhA markedly decreased after bariatric surgery and slightly increased after training programs. Conclusions Thus, a relatively low number of studies have evaluated PhA in individuals/patients with obesity with sometimes contradictory and preliminary results. PhA might be useful to evaluate muscle quality in individuals/patients with obesity but further studies are needed to more accurately associate this variable with changes in muscle structure and strength, as well as in metabolic functions.

Introduction. The purposes of this study were 1) to evaluate changes from baseline levels in bioelectrical phase angle (PhA) and markers of muscle damage and inflammation in professional players 36 h after a soccer match, and 2) to analyze the relationships between PhA and markers of muscle damage and inflammation in order to investigate if PhA might be a useful parameter to monitor recovery. Material and methods. Eighteen male professional soccer players participated in this study. Plasma lactate dehydrogenase (LDH) and creatine kinase (CK) activities, plasma C-reactive protein (CRP) and interleukin-6 (IL-6) concentrations, and PhA were measured before and 36 h after a competitive match. Results. Changes in LDH and CK 36 h after the match were greater than their reference change values (RCV). Changes in CRP and IL-6 were, however, lower than their corresponding RCV. 36 h after the match, significant correlations were observed between PhA and LDH (r = 0.714, p = 0.001), PhA and CK (r = 0.787, p = 0.000), and PhA and CRP (r = 0.554, p = 0.017). Conclusions. Although IL-6 and CRP have been traditionally analyzed together to monitor inflammation after intense exercise, since 36 h after the match they have already returned or started to return to baseline levels, the use of them alone is not a good option to monitor inflammation throughout recovery. PhA might be used as a predictor of muscle damage and inflammation, but further studies covering the whole recovery period are warranted.

Background Malnutrition status, body composition indicators, and bioelectrical impedance analysis (BIA) parameters have been associated with increased risk of death in several pathologies. The aim of this study was to describe the associations between phase angle (PhA) indicators obtained by BIA with length of hospital stay, days on mechanical ventilation, and 60‐day mortality in critically ill patients infected with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). Methods This is a prospective cohort of mechanically ventilated patients with coronavirus disease 2019 (COVID‐19). We assessed nutrition risk and body composition with BIA within 48 h from intensive care unit admission. Logistic and linear regression models were used to analyze the association between variables and clinical outcomes. Survival analysis by PhA value was performed using Kaplan‐Meier curves. Results Sixty‐seven patients were included. PhA (odds ratio [OR], 0.36; P = .002), standardized PhA (SPA) (OR, 0.45; P = .001), and extracellular water/total body water ratio (OR, 3.25; P = .002) were significant predictors of 60‐day mortality. PhA

Phase angle through electrical bioimpedance as a predictor of cellularity in inflammatory bowel disease

During pregnancy, body composition alterations can be considered as markers of complications and in this context, a non-invasive and low-cost method such as Bioelectrical Impedance Vector Analysis (BIVA), can be employed to monitor such changes. This study aimed at identifying body compartments trend during physiological pregnancy.Classic and specific BIVA variables have been measured in a sample of 37 pregnant women approximately every 4 weeks of gestation and once postpartum. Researchers used both longitudinal and cross-sectional approach. The first case included data of women from the 11th to the 15th week along with data from the 28th to the 32nd week of gestation. The cross-sectional approach regarded two more specific moments (11th-12th weeks and 30th-31st weeks) and data within two months postpartum RESULTS: The longitudinal approach showed a significant decrease in classic BIVA variables (R/H, Xc/H, Z/H p 0.001) and a shortening of the vector, pointing out that TBW and hydration increased significantly. Specific vector length increased significantly, indicating a physiological gain of FM% (p 0.01). The cross-sectional approach showed lower values of R/H, Xc/H, Z/H between 12th-13th and 30th-31st weeks (p 0.01), while in the postpartum period values tended to those registered at the beginning of pregnancy. No changes have been found for the phase angle in both approaches, indicating that ECW/ICW ratio remained constant CONCLUSIONS: Among physiological pregnancies, bioelectric values showed a coherent trend and these results represent a first contribution to support routine exams, leading to an early detection of anomalous values potentially correlated to pathologies.

The interoperability between the vehicle assembly and ground assembly of wireless charging systems has been specified in international standards. SAE J2954 first proposed an interoperability evaluation method based on interface impedance. However, the impedance measurement is challenging at high frequency since the phase difference between the voltage and current is not easy to measure accurately, especially when it is close to 90°. Small errors in phase angle measurement are amplified in impedance calculation due to the sine/cosine function. This letter proposes an impedance measurement method using the power decomposition algorithm. By decomposing the input power into two orthogonal components, the impedance angle can be calculated without directly measuring the phase difference between the voltage and current. Thus, the measurement results of the impedance angle do not introduce errors. With the proposal, the high-cost probe or complex high-precision phase difference measurement circuit is not needed. The experimental results show that the conventional method's maximum relative error reaches 80%, making interoperability hard to determine. Reversely, with the proposed method, the relative error of impedance measurement is reduced to less than 10%.

Summary Background and aims Thus, the aim of this study was to assess the changes in the body composition of the women survivors of breast cancer and its association with clinical staging, using the bioelectrical impedance vector analysis (BIVA), over five years of follow-up. Methods At baseline time 114 patients (T0) were selected and after 5 years (T1) of follow-up (n = 35) data of weight, body mass index, waist circumference, phase angle, resistance/height, reactance/height, %fat free mass and %fat mass were monitored. Bioelectrical impedance vector analysis (BIVA) and the vector displacement assessment took place according to the initial and advanced clinical staging (CS 1 and 2, respectively) and time of follow-up and have been showed using mean graph and RXc score graph. Results Patients on CS 1 showed a reduction in reactance/height, phase angle, %fat free mass and an increase in %fat mass. The same group presented during the follow-up significant vector displacement by mean graph and a change to the 95% ellipse by the RXc score graph. Conclusions Women with breast cancer in the initial CS showed a more significant displacement of bioelectric vectors, indicating worsening in body composition.

As estruturas dos pavimentos estão na maioria das vezes sujeitas às cargas dinâmicas resultantes de várias combinações de carregamentos decorrentes dos veículos e diferentes condições ambientais. O desempenho de concretos asfálticos em termos de comportamento viscoelástico linear pode ser previsto usando o comportamento tensão- -deformação que pode ser definido pelo módulo complexo. Dentre as opções mais modernas para sua obtenção, encontram-se os testes de flexão a quatro pontos. Neste contexto, o trabalho avalia a viabilidade técnica do uso do grafite comercial em camadas de pavimentos rodoviários. Para isto, foram produzidas duas misturas asfálticas, uma confeccionada com cimento Portland, codificada por CA-REF e outra produzida com grafite comercial (CA-GRAFP). Para atingir o objetivo desta pesquisa, as composições asfálticas foram submetidas ao ensaio de flexão a quatro pontos para obtenção do módulo complexo e o ângulo de fase. A metodologia adotada seguiu as recomendações da norma europeia EN 12697-26, com aplicação de carregamento de compressão senoidal uniaxial e amplitude de deformação de 50μm/m, frequências de 0,1 a 20Hz e temperaturas de 0 a 40°C, com incrementos de 5 em 5 °C. Os resultados da pesquisa evidenciaram que o CA-GRAFP apresentou módulos complexos superiores ao CA-REF. Além disso, foi possível observar menores valores dos ângulos de fases para composição CA-GRAFP. Os resultados obtidos neste estudo apontam para a viabilidade do uso do grafite como material aplicável em pavimentos rodoviários.

The Shear Tester with Normal Stress (STNS) is developed in this study for measuring the fundamental shear properties of asphalt mixes at a low cost. The device can shear an asphalt concrete specimen subjected to controlled normal stress of 113 kPa (16.35 Psi). A total of 72 test specimens of three asphalt mixes, produced at different daily times, were tested for the Frequency Shear Test at Normal Stress (FSNS) and Repeated Shear Test at Normal Stress (RSNS). The FSNS test was used to measure the dynamic shear modulus |G*| and shear phase angle (δ), whereas the RSNS test was conducted to measure the permanent shear deformation for asphalt mixes. The results showed that the average values of the measured |G*| and (δ) have generally the same trends over the shear load frequencies for all mixes. All sample groups have average permanent shear deformations of less than 1.1 mm at 5000 repeated shear loads. The shear phase angle had comparable variabilities to that of the dynamic shear modulus at high shear load frequencies. The measured permanent shear deformations had variabilities of less than 17% for all mixes.

Background and objectives: An arteriovenous fistula is considered to be an ideal vascular access for patients receiving hemodialysis, its main limitation is its high failure rate to achieve maturation and long-term functionality loss. Multiple strategies have attempted to identify patients at risk. Bioelectrical impedance has shown to be a valuable resource in the determination of the hydration status, and the measurement of the phase angle through this method has demonstrated to be a good indicator of the nutritional state and its related as a general marker of survival. The objective of this study is to analyze the role of plasma albumin and phase angle measured through bioelectrical impedance as tools useful for predicting failure of arteriovenous fistulas. Materials and methods: prospective observational study, including 104 patients with chronic kidney disease receiving hemodialysis who underwent a native arteriovenous fistula during a period of 24 months. Analyzing its clinical characteristics, laboratory and phase angle through electrical bioimpedance, both univariate and multivariate analysis was performed both with logistic regression, furthermore calculation of coordinates and ROC curve to establish a better cut-off point. Results: of the variables that were analyzed only the phase angle measurement showed statistical significance OR 2.61 (1.6 – 4.4) p - value 0.001 for predicting arteriovenous fistula failure. In female patients with a phase angle value of 3.25 had a 90% sensibility and 53% specificity for male patients a value of 3.58 showed a sensibility of 84% and a specificity of 52% with ROC curve of 0.78. Conclusion: phase angle through bioimpedance is a useful parameter, helpful in predicting failure of native arteriovenous fistula, it is also an important tool for identifying patients at risk, in early stages prior to the construction of a vascular access.

One of the important parameters for electrical systems is the power factor (cos phi), which is the ratio of the real power (watt) to the apparent power (volt ampere). The best cos phi value is between 0.85 to 1. A resistive load causes the voltage and current in equal phase angle, while the inductive load causes the current to lag behind the voltage. On the other hand, the capacitive load causes the current to precede the voltage (leading). A simulation to determine the power factor of an electrical network can be done with Proteus ISIS software by creating a phase detection circuit. Automatic control can be done by a microcontroller. This simulation circuit can be used as power factor correction, a trigger angle on SCR trigger for DC motor speed control, for rocket launch angle adjuster, to measure the angle of inclination, and other uses relating to angle adjustments.

In this study, the effect of phase shift under multiaxial excitation on fatigue damage was investigated for the roof components of electrical driven bus. The experiments were performed using a servo-hydraulic controlled multiaxial shaker. Firstly, phase degree and concurrence of servo-hydraulic actuators were calculated and compared for in-phase and out-of-phase loading cases. Following response signals of both loadings were acquired to investigate the dynamic response of the structure and roof components. Both test loadings were compared by level crossing counting and damage calculations in the frequency domain. The results indicate that the out-of-phase loading can reduce the acceleration and strain values on the flaps induced damage significantly compared to in-phase loading. Furthermore, the out-of-phase loading of bench testing corresponds well to the experimental results of rough road, which represent customer drive conditions.

Summary Background & aims The accuracy of estimating body composition compartments is critical in the clinical setting. Currently, there are different bioelectrical impedance analysis (BIA) devices available for obtaining raw BIA parameters. The aim of this study was to determine the level of agreement between multiple frequency (MF)-BIA and single frequency (SF)-BIA devices in obtaining raw BIA measurements (resistance (R), reactance (Xc), and phase angle (PhA)), as well as the agreement on the classification of hydration status and body cell mass by the bioelectrical impedance vector analysis (BIVA) method. Methods This cross-sectional study included 406 outpatients with stable chronic heart failure (HF). The raw BIA measurements at 50 kHz obtained by tetrapolar MF-BIA (Bodystat QuadScan 4000) were compared with those obtained by tetrapolar SF-BIA (RJL Quantum X). In addition, the patients were classified by their hydration status and body cell mass according to the BIVA method. Results Strong and significant correlations were observed between the two methods in all raw BIA variables (r ≥ 0.90). Lin's concordance correlation coefficient (CCC) values were almost perfect for R (CCC = 0.99; 95% CI 0.997 to 0.998), moderate for Xc (CCC = 0.93; 95% CI 0.92 to 0.94), and poor for PhA (CCC = 0.88; 95% CI 0.85 to 0.90). The agreement obtained in the two classifications (quadrants and hydration status) was >0.81. Conclusions MF-BIA and SF-BIA demonstrated good agreement for measurement of the R parameter; however, the Xc and PhA parameters must be used carefully due to the previously reported variability. Likewise, the agreement in all classifications by the BIVA method was almost perfect.

BACKGROUND In soccer, a better understanding of the bioimpedance parameters with physical performance may be useful to efficiently monitor and interpret players' performance variation throughout a certain period of the season. Therefore, this study aimed to examine the association between phase angle (PhA) and arms and legs lean soft tissue (ALST and LLST) with physical performance in young elite soccer players. METHODS Fifteen young male elite soccer players (age = 14.2±1.2 years, BMI = 20.51±1.38 kg/m2) participated in this investigation. Raw bioimpedance parameters (reactance, resistance, and phase angle) were obtained by a bioelectrical impedance analysis (BIA) device. Then, ALST and LLST were estimated. All players underwent a physical testing battery including countermovement jump (CMJ), 10-m and 20-m sprint, and Yo-Yo Intermittent Recovery Test level 1 (YoYo IRTL1) in the domains of anaerobic and aerobic performance, respectively. RESULTS The results showed that LST (total, arms and legs) positively correlated with CMJ (0.64 < r < 0.69; p < 0.001) and negatively correlated with 10-m (-0.59 < r < -0.63; p < 0.05) and 20-m sprint (-0.67 < r < -0.73; p < 0.001), while PhA positively correlated with CMJ (r = 0.57; p < 0.05) and negatively correlated (r = -0.54; p < 0.05) only with 20-m sprint. No significant association was found between the BIA-related parameters (PhA and LST) and Yo- Yo IRT level 1. CONCLUSIONS The present findings highlight the existing association of PhA and LST with jumping and sprinting performance in young elite soccer players. This result supports the use of BIA-related measures as a simple and practical approach to monitoring anaerobic performance changes, rather than aerobic, over time throughout the season.

The polarity status is one of the important items of specifications of trigger signal from cardiac trigger monitors with two options, either positive or negative. Some systems allow the user to set the polarity of trigger signal before imaging. Efforts should be made to set the polarity status according to the recommendations provided by the manufacturers. In case of inappropriate selection, changes in computation of end-systolic and end-diastolic volumes as well as ejection fraction may occur. To investigate the effect of the polarity status of trigger signals in synchronization process during 8- and 16-frame gated SPECT imaging on the systolic and diastolic parameters of LV function. Thirty-four patients referred for a myocardial perfusion SPECT were consecutively included in the study. The rest scan for each patient was performed with 8- and 16-frame gating simultaneously with positive trigger signal set by the operator in a cardiac trigger monitor and then repeated after manual selection of negative polarity. In total, the 4 imaging modes acquired were 8-frame/positive-trigger, 16-frame/positive-trigger, 8-frame/negative-trigger, and 16-frame/negative-trigger. All SPECT images were reconstructed and processed with the same values of parameters. Systolic and diastolic indices of LV function were derived in QGS of the Cedars-Sinai software and then were compared using various statistical tests, and a reliability analysis was also performed. The age of patients recruited in the study was 58.41 ± 8.94, and 16 (47.1%) males and 18 (52.9%) females. All the correlation coefficients between corresponding parameters in positive and negative trigger signals were statistically significant. The difference between the parameters of systolic function including EF, EDV, and ESV in positive and negative trigger signals was statistically significant in paired sample t test. Likewise, a statistically significant difference was also found between mean phase angle in scans with positive and negative trigger signals by a phase difference of 147.91 (41.0% of an average cardiac cycle) and 149 (41.3% of an average cardiac cycle) degrees in 8- and 16-frame gating modes, respectively. Strong agreement (according to high values of intra-class correlation coefficient) was found for all four pairs. According to Bland-Altman results, an offset of about 3 percentage units was found, both between imaging in 8-frame gating compared to 16-frame gating, higher value in favor of 16-frame gating, and also between imaging with positive polarity trigger compared to negative-polarity trigger, again higher value in favor of positive-polarity triggering. The status of the polarity of trigger signals or similar CTM-camera delays in synchronization process during 8- and 16-frame gated SPECT imaging can be considered as one of the factors that may influence systolic and diastolic indices of LV function

Phase angle is an important property of asphalt concrete (AC) mixtures that can aid in proper material selection and thereby assist in accurate design of flexible pavements. In particular, it is imperative to quantify differential phase angle behaviour for varying mixture characteristics to minimise premature failure of flexible pavements. To this end, this study aims to provide insights into the differential phase angle behaviour of wearing versus base course mixtures, field versus laboratory prepared mixtures, and for a full spectrum of binder grades. To achieve this research aim, this study employs a two-step framework. First, an artificial neural network (ANN) model is developed to predict phase angle using laboratory test data as input. Twenty-three AC mixtures consisting of different penetration grade binders, varying mix proportions, and mix types are used for phase angle testing performed at four testing temperatures (4.4, 21.1, 37.8, and 54.4 °C) and six loading frequencies (25, 10, 5, 1, 0.5, and 0.1 Hz) using the asphalt mix performance tester equipment. In the second step, a sensitivity/parametric analysis is performed for the phase angle model revealing the differences in phase angle characteristics of wearing and base course, field and laboratory mixtures as well as mixtures prepared with different binder grades. Furthermore, a comparison of the proposed ANN model with linear and non-linear regression models is performed, and the ANN model outperforms the competing models. The developed ANN model can be used as a surrogate to laboratory testing and utilised by transport departments and pavement analysts to characterise the phase angle behaviour of heterogenous AC mixtures.

Partial discharge (PD) measurement is a diagnostic technique used for electrical insulating systems. The establishment of a highly accurate PD diagnostic technique has become necessary in recent years. Therefore, in this study, we analyzed a phase-resolved PD signal using machine learning classification for different types of experimental electrode systems. A polyethylene sheet was used as the sample, and PD was generated by applying a high AC voltage to four different types of electrodes. The number of PD pulses was counted from the raw data as preprocessing to calculate the feature value for the machine learning. The PD generation rate was defined for each phase angle section. Four types of machine learning algorithms were adopted for the classification of the electrode system: k-NN (k-nearest neighbor algorithm), logistic regression, decision tree, and random forest. The best accuracy was obtained by using the random forest algorithm (0.97), and it was found that k-NN also demonstrated good performance. The parameter dependencies were also evaluated for each algorithm. Based on the results generated by the random forest, it became clear that there were phase angle sections that were of high importance. The reason for the result was discussed from the perspective of (i) the difference due to the electrical circuit parameters (modified abc-model) and (ii) the stochastic fluctuation of PD signal.

Objective To investigate the ability of phase angle (PA) and body composition for predicting protein energy wasting (PEW) in renal replacement therapy (RRT) patients. Methods Renal replacement therapy (RRT) patients were enrolled in this study. Body composition was measured by direct segmental multi‐frequency biolectrical impedance analysis method (DSM‐BIA); phase angle (PA), fat‐free mass (FFM), fat mass (FM), mid‐arm circumference (MAC), WC (waist circumference), and ECW/TBW (extracellular water/total body water) were obtained. Biochemicals (serum albumin, triglyceride, and cholesterol) were tested. PEW patients were classified according to ISRNM (The International Society of Renal Nutrition and Metabolism) criteria. Cutoff value of PA and related variables was calculated by ROC analysis. The ability of body composition variables as indicators to predict PEW was evaluated. Results Sixty‐four patients were enrolled in this study. Thirty‐three patients (52.6%) were males, and forty (62.5%) patients were diagnosed with PEW. The ROC curve showed that the optimal cutoff values of PA, FFMI (fat‐free mass index), MAC, WC, and BMI for PEW risk were 4.45°, 16.71, 29.7 cm, 86.4 cm, and 21.1 kg/m2, respectively. These indicators showed significant association with PEW; meanwhile, the PA and MAC can be used as the predictors for PEW with OR 6.333 (95% CI, 1.956–20.505) and 3.267 (95% CI, 1.136–9.394), respectively. Both groups have a lower BUN/Cr ratio (, Protein energy wasting is prevalence in chronic kidney disease (CKD) patients on renal replacement therapy by the International Society of Renal Nutrition and Metabolism. Phase angle and mid‐arm circumference can be used as the independent and reliable indicators for the noninvasive predicting of protein energy wasting and evaluating nutrition status in CKD patients.

The article is a continuation of the author's earlier considerations concerning the methods of testing shock absorbers installed in the vehicle. The work concerns the analysis of the usability of two methods: the EUSAMA method and the phase angle method. The first one examines the minimum ratio of the force in contact between the wheel and the vibration-inducing plate (on which the wheel of the tested suspension rests) and the static value of this force. The second one uses the minimum of the phase shift angle between the excitation (vertical movement of the said plate) and the force in contact between the tire and this plate for diagnosis. Two linear quarter-car models and their description in the frequency domain were used to evaluate two analyzed methods. For both evaluated methods, the monotonicity of the dependence of the diagnostic parameter on the diagnosed one (damping in suspension) is visible; in the case of the phase angle method it is close to linear. The correction of the results related to the inertia of the vibration-inducing plate was considered. The calculations were made for two typical data sets: for the front and rear suspension of a middle-class passenger car. They allow a general qualitative and (to a limited extent) quantitative assessment of the usefulness of the analyzed methods. For the EUSAMA method, the test result has a noticeable effect of the inertia of the vibration-inducing plate. This confirms the legitimacy of correcting the force measured in the diagnostic stand. Values without correction are more optimistic. For cars with a low weight or a lightly loaded road axle (especially the rear axle) of heavier vehicles, low values of the diagnostic parameter are obtained, suggesting a bad condition of the shock absorbers, which is not confirmed by their examination in the state removed from the vehicle. In the second assessed method, there are clear differences between the values of the phase angle obtained based on testing the force in the wheel-plate contact and those obtained for the analysis of the force measured in the test stand. Therefore, the correction for the value of the station plate inertia force is significant. Values without correction are more pessimistic, although it is not justified in the condition of the tested vehicle. The works cited in the article describe several practical drawbacks of the phase angle assessment method. The author points to the importance of further research, much more laborious, with the use of nonlinear models and the necessary experimental verification of the obtained simulation results.

Purpose In patients living with Anorexia Nervosa (AN), dehydration and haemoconcentration, may prevent a correct interpretation of laboratory nutritional parameters. Our study aims to evaluate if some indicators of disease severity, as body mass index (BMI), Phase Angle (PhA) and months of amenorrhea may be predictors of metabolic alterations (serum albumin, liver enzymes). Methods In 154 outpatients with AN, case history was collected, and anthropometric and laboratory parameters measured. Patients were divided according to the following tertiles (T) of BMI, duration of amenorrhea and PhA: (1) BMI (T1 16.8 kg/m2); (2) Amenorrhea duration (T1 14 months); (3) PhA value (T1 5.35°). ROC curves were used to determine which of these three indicators (BMI, PhA and amenorrhea duration) might better identify patients belonging to Group A or B (less than 3 or more metabolic abnormalities). Results The most frequent registered metabolic alterations were for alkaline phosphatase (ALP), alanine aminotransferase, cholesterol and hemoglobin. Aspartate aminotransferase, ALP and gamma glutamyl transferase abnormalities were frequent in the first tertiles of all the three indicators. Albumin was low in the T1 of BMI and PhA. No differences in nutritional alterations emerged according to amenorrhea duration. PhA had the best performance (AUCs: 0.721) in identifying patients with 3 or more abnormalities, with the optimal cut-off value of 4.5°. Conclusions Our data confirmed PhA as the more reliable predictor of metabolic alterations, followed by BMI and amenorrhea duration, especially in the first tertile. Evidence-based medicine Level 2.

Bioelectrical impedance analysis (BIA)-derived phase angle (PhA) has been used to assess cellular health in various populations, but its usefulness as a tool for measuring muscular performance in adult athletes has not been extensively investigated. Our investigation examined the association of whole-body (WB) PhA with muscular performance in 117 adult athletes from different sports and additionally assessed whether regional PhA was a better indicator of muscular performance compared to WB, while accounting for lean soft tissue (LST). Muscular performance was assessed with handgrip strength and countermovement jump power. WB and regional PhA and LST were obtained by BIA and dual-energy x-ray absorptiometry, respectively. Multiple linear regression was used to model outcomes, while adjusting for LST. WB PhA was positively associated with relative power and relative and absolute strength (p < 0.05), irrespective of LST. Regional PhA measures explained similar amounts of variance in absolute and relative power and strength as that of WB PhA after accounting for age, sex, height, and sport type (lower limb adj R 2 = 0.42, 0.60 for power; upper limb adj R 2 = 0.38, 0.74 for strength; WB adj R 2 = 0.44, 0.63 and 0.38, 0.75 for power and strength, respectively). Only upper limb PhA was related with strength (p < 0.05) after accounting for upper limb LST. PhA may have the potential to be used as a marker of functional muscle mass, which is important when it comes to assessing muscular performance of athletes. Regional measures of PhA do not provide a better indicator of regional strength or power when compared to WB PhA.

Recent advances in distribution-level phasor measurement unit (D-PMU) technology have enabled the use of voltage phase angle measurements for direct load sharing control in distribution-level microgrid interconnections with high penetration of renewable distributed energy resources (DERs). In particular, D-PMU enabled voltage angle droop control has the potential to enhance stability and transient performance in such microgrid interconnections. However, these angle droop control designs are vulnerable to D-PMU angle measurement losses that frequently occur due to the unavailability of a GPS signal for synchronization. In the event of such measurement losses, angle droop controlled microgrid interconnections may suffer from poor performance and potentially lose stability. In this paper, we propose a novel distributed mixed voltage angle and frequency droop control (D-MAFD) framework to improve the reliability of angle droop controlled microgrid interconnections. In this framework, when the D-PMU phase angle measurement is lost at a microgrid, conventional frequency droop control is temporarily used for primary control in place of angle droop control to guarantee stability. We model the microgrid interconnection with this primary control architecture as a nonlinear switched system and design distributed secondary controllers to guarantee transient stability of the network. Further, we incorporate performance specifications such as robustness to generation-load mismatch and network topology changes in the distributed control design. We demonstrate the performance of this control framework by simulation on a test 123-feeder distribution network., Comment: 11 pages, IEEE Open Access Journal of Power and Energy (accepted)

Based on the study of phase angle and wavelength in pBRDF (Polarized bidirectional reflectance distribution function), roujean model was proposed to describe Orient (Polarization phase angle) quantitatively. The Roujean model was used to quantitatively describe different fruits intensity components (F00) and polarization phase angle (Orient), and the simulation results were analyzed and compared using statistical analysis and comparison methods to realize the prediction from the regular model to the outdoor fruit tree canopy to the canopy of outdoor fruit tree canopy random distribution. The experimental results showed that: 1) when the phase angle of jujube was 52.19°, 66.51° and 88.26°, the R2 and average errors of F00 parameters described by Roujean model are 0.9982, 0.9963, 0.9912 and 3.80%, 4.17%, 6.40%, respectively; and the R2 and average error of Orient parameters described by Roujean model are 0.9056, 0.9223, 0.9260 and 6.23%, 3.32%, 8.05%, respectively; It can be seen that roujean model can quantitatively describe the Orient parameter of jujube; 2) When the phase angle of apricot was 70.99°, 71.28° and 67.91°, the R2 and average errors of F00 parameters described by Roujean model is 0.9862, 0.9823, 0.9792 and 3.40%, 4.82%, 5.19%, respectively; And the R2 and average error of Orient parameters described by Roujean model are 0.9382, 0.8947, 0.8849 and 7.19%, 9.28%, 9.47%, respectively. Roujean model can also quantitatively describe the Orient parameter of white apricot. In summary, the Roujean model can provide a good quantitative description of f00 and a good quantitative description of Orient, which in turn can predict the pBRDF parameter for more fruits with different incidence and detection directions. It can correct the influence of angle factor in the nondestructive testing of outdoor fruits.

Background Our aim was to elucidate whether Hb variability affects nutritional status in HD patients. Methods This study included chronic HD patients (n = 76) with available monthly Hb levels up to 24 months prior to the body composition monitoring (BCM) measurement. The parameters obtained in the BCM included body mass index (BMI), lean tissue index (LTI), fat tissue index (FTI), body cell mass index (BCMI), overhydration/extracellular water ratio (OH), and phase angle (PhA). The coefficient of variation (Hb-CV), standard deviation (Hb-SD), and range of Hb (Hb-RAN) were used as indexes of Hb variability. In addition, minimum (Hb-Min), maximum (Hb-Max), average (Hb-Avg), and median (Hb-Med) Hb levels (g/dL) were analyzed. Results There were no significant differences in clinical, biochemical, and nutritional indexes based on the Hb-CV level. Compared to patients with an Hb-Med ≤ 10.77, those with an Hb-Med >10.77 had higher albumin levels, total iron-binding capacity (TIBC), and PhA and lower average weekly prescribed darbepoetin. Age, female sex, OH, and darbepoetin dosage were negatively correlated with PhA. Serum albumin, phosphorus, TIBC, Hb-Med, and Hb-Avg were positively correlated with PhA. In multiple linear regression analysis, PhA was positively associated with Hb-Med and serum albumin level, whereas PhA was negatively associated with age and female sex. The area under the curve (AUC) of Hb-Med was 0.665 (p = 0.040) in predicting PhA >5.00° Conclusions PhA was not affected by indexes of Hb variability, whereas PhA was associated with Hb-Med in chronic HD patients.

Summary Background & aims Gaining insight into readily obtainable baseline characteristics that allow prediction of adverse outcome in COVID-19 aids both treatment and healthcare planning. Bioelectric impedance (BIA) Phase Angle (PhA) is correlated with outcome in a multitude of diseases and may be of added value in predicting adverse outcome of COVID-19. We aimed to associate baseline body composition parameters with 90-day adverse outcome of COVID-19 including ICU-admission and to explore the added predictive value of baseline PhA. Methods We performed a prospective observational study, conducting BIA amongst COVID-19 patients within 24 hours of hospital admission, with a follow-up of 90 days. Data were compared between ward-only and ICU-patients. Regression models were used to assess the associations between baseline characteristics, body composition and 90-day adverse outcome, including a composite outcome score of morbidity, ICU-admission, and mortality. An ROC-curve was used to explore the added predictive value of PhA to other clinical parameters at baseline for the prediction of adverse outcome. Results One-hundred-and-fifty patients were included. Mean age was 68 (66–70) years, 67% were male. Forty-one (27%) patients were admitted to ICU and 77 (51%) met the criteria of the composite outcome score. In multiple regression, PhA was independently, inversely correlated with risk of ICU-admission (OR .531, p = .021), complications (OR .579, p = .031), hospital length of stay (OR .875, p = .037) and the composite outcome score (OR .502, p = .012). An ROC-curve showed that the incorporation of PhA in a composite risk-score improved the discriminative power for the composite outcome from poor to fair, compared to individual predictors (AUC 0.79 (95% CI 0.71–0.87)). Conclusion BIA measurements including Phase Angle are independently correlated with an adverse outcome of COVID-19. Interpretation of Phase Angle can be a valuable addition to risk assessment of adverse outcome of COVID-19 at hospital admission. Clinical Trial Registration Netherlands Trial Register number NL8562, registered 2020-04-21.

A stress-based sectional critical plane model for multiaxial fatigue life prediction is proposed. The proposed model considers the effects of material properties and loading paths on the crack initiation and propagation behaviors. By introducing the ratio of maximum shear stress amplitude to maximum normal stress amplitude, it is divided into three sections in which the maximum normal stress plane, maximum damage plane and maximum shear stress amplitude plane are considered as the critical planes, respectively. To verify the accuracy and applicability of the proposed model, experimental data of 30CrMnSiA steel conducted by the authors and other test data of different materials from the existing literatures are utilized. For 30CrMnSiA steel, the prediction results of the proposed model demonstrate that 79.3% and 93.7% of the prediction results are within the ±2 times and ±3 times scatter band of fatigue life. For the experimental data from the existing literatures, more than 85% and 70% of the results predicted by the proposed model are within ±3 times scatter band of fatigue life for steel and aluminum alloy materials, respectively.

In this study, in order to determine critical values of a load bus with respect to voltage stability, two different estimation approaches using local measurements of voltage (V), current (I) and phase angle (φ) on the relevant bus are investigated. First, Thevenin equivalent circuit parameters of the power system is estimated from local bus measurements; then, the critical voltage and voltage stability margin values required for evaluation of the voltage stability are calculated. The proposed approach has been tested on the IEEE 30 bus test system. In IEEE 30 standard test system, the data of the buses to be analyzed was acquired by setting up a power flow with MATPOWER software. The simulation results show that both approaches have successfully determined the voltage stability limits on the load buses and they can be used to evaluate the loading levels of the buses in terms of voltage stability, to determine the critical buses and to prioritize the load shedding operations., Bu çalışmada, gerilim kararlılığı açısından bir yük barasındaki kritik değerlerin belirlenmesi için, ilgili baraya ait gerilim (V), yük akımı (I) ve güç açışı (φ) yerel ölçümlerini kullanarak kestirim yapan iki farklı yaklaşım irdelenmiştir. İlk olarak, yerel bara ölçümlerinden güç sisteminin Thevenin eşdeğer devre parametreleri kestirilmiş, ardından gerilim kararlılığının değerlendirilmesi için gerekli kritik gerilim ve gerilim kararlılık marjini değerleri hesaplanmıştır. Sunulan yaklaşım IEEE 30 baralı test sistemi üzerinde denenmiştir. IEEE 30 baralı standart test sisteminde MATPOWER yazılımı ile güç akışı yapılarak incelenecek baralara ait veriler elde edilmiş ve her iki yöntem ile gerilim kararlılığı değerlendirmesi gerçeklenmiştir. Benzetim sonuçları, iki yaklaşımında yük baralarındaki gerilim kararlılık sınırlarını başarı ile belirlediği ve baraların gerilim kararlılığı açısından yüklenme düzeylerinin değerlendirilmesinde, kritik baraların tespitinde ve yük atma işlemlerinin önceliklenmesinde kullanılabileceğini göstermiştir.

Background Obesity is a global health problem that is continuing to increase in the young population. In Brazil, the frequency of obesity in 2018 was 19.8%. Several comorbidities are directly associated with obesity, such as non-alcoholic fatty liver disease (NAFLD), which is considered the most common liver disorder in Western countries and affects up to 46% of adults. Bariatric surgery is effective in treating obesity and can improve NAFLD; however, the effect of bariatric surgery on body composition, phase angle (PA), and improving NAFLD needs to be further studied. Aim To analyze the PA in the postoperative period of bariatric surgery and to correlate it with changes in body composition and liver disease. Methods This study is a retrospective cohort study of the analysis of the medical records of patients undergoing bariatric surgery in a reference center of a teaching hospital in Porto Alegre over a 2-year period. Patients older than 18 years whose record contained all information relevant to the study were included. The data analyzed were body composition and PA through electrical bioimpedance and NAFLD through liver biopsy in the pre- and postoperative period. The level of significance adopted for the statistical analyses was 5%. Results We evaluated 379 patients with preoperative data. Regarding PA, 169 patients were analyzed, and 33 patients had liver biopsy pre- and postoperatively with NAFLD information. In total, 79.4% were female, with a mean age of 39.1 ± 10.6 years. The average body mass index (BMI) was 45.9 ± 7.5 kg/m². The PA showed a mean of 5.8 ± 0.62° in the preoperative period and a significant reduction in the postoperative period. A postoperative reduction in body composition data (skeletal muscle mass, fat percentage, fat mass, body cell mass, BMI and visceral fat area) was shown as well. Regarding liver disease, all patients presented a reduction in the degrees and stages of liver disease in the postoperative period, and some had no degree of liver disease at all. Conclusion PA decreased after bariatric surgery, with a direct correlation with weight loss and changes in body composition. The decrease in PA was not correlated with the improvement in NAFLD.

To maintain a critical process upon loss of primary motor bus power, the petrochemical industry depends largely on residual voltage transfer, ignoring phase angle and closing the backup source when the motor bus residual voltage has decayed to 30%. To assess the consequences of out-of-phase residual voltage transfers, a transient simulation program models a bus with three motors of various sizes, inertias, and impedances. The three motors are loaded around 80% with fan, pump, and compressor loads to calculate the peak transient motor current and torque upon closure of the backup source breaker. Pre-transfer events and conditions produce an initial phase angle between the primary and backup sources, and the simulation reproduces the resultant residual voltage transfer closing angle and its effect on the peak transient current and torque. Individual motors exhibit positive and negative torques, oscillating from induction generator to motor, and the peak-to-peak torques are also recorded, as they can impact the motor shaft stress.

Objectives To investigate whether phase angle (PhA) measured by bioelectrical impedance analysis (BIA) and frailty are associated with the outcomes of critical illnesses. Design A single-center prospective cohort study. Setting Medical intensive care unit (ICU) in Seoul National University Hospital, Seoul, Republic of Korea. Participants 97 patients who were admitted to the medical ICU. Measurements On admission, PhA was measured by BIA, and frailty was assessed by the Korean Modified Barthel Index (KMBI) scoring system. Patients were classified according to PhA and KMBI scores, and their impact on the outcomes of critical illnesses was evaluated. Results The patients’ mean age was 62.4 ± 16.4 years, and 56 of the patients (57.7%) were men. Having a high PhA above 3.5 at the time of ICU admission was associated with lower in-hospital mortality (adjusted OR 0.42, p =.042), and a shorter duration of ICU stay (5.6 days vs. 9.8 days, p =.016) compared to those with a low PhA. Other indices measured by BIA were not significantly associated with outcomes of critical illnesses. Frailty (KMBI > 60) was associated with more mechanical ventilation days (2.3 days vs. 7.1 days; p =.018). Conclusion Both PhA and frailty are important prognostic factors predicting the outcomes of critical illnesses. Low PhA scores were associated with increased mortality and a longer duration of ICU stay, and frailty was associated with more mechanical ventilation days.

This study examined whether phase angle (PhA) is associated with hip osteoarthritis (HOA) severity and quadriceps strength in patients with HOA.A series of 549 patients with HOA, obtained from the Screening for People Suffering Sarcopenia in the Orthopedic cohort of Kobe study, were analyzed. PhA and quadriceps strength were measured using bioelectrical impedance analysis and a handheld dynamometer, respectively. The HOA severity was graded using the Kellgren-Lawrence radiographic scale. We estimated (1) mean differences in PhA by differences in HOA severity and (2) mean differences in quadriceps strength by differences in PhA using general linear models.The patients' mean age was 64.9 years, and 85% were women. A decreasing trend of PhA associated with increasing HOA severity was observed (P for trend0.001). PhA was statistically associated with a decrease in HOA grade 4 compared with that associated with HOA grade 1 (mean difference, - 0.40°; 95% confidence interval (CI), - 0.51° to - 0.30°). PhA per leg was associated with greater quadriceps strength per leg independent of age, sex, leg muscle mass, and HOA severity (mean difference per 1° increase, 3.80 Nm; 95% CI, 0.93 to 6.66). There was insufficient evidence of any difference in the association between PhA and quadriceps strength by HOA severity and sex (P for interaction = 0.07 and 0.06, respectively).PhA gradually decreased with increasing HOA severity, especially in patients with end-stage HOA. Paying close attention to PhA might provide a key to increasing quadriceps strength, regardless of HOA severity. Key Points • PhA gradually decreased with progression of HOA, particularly in patients with end-stage HOA. • PhA was positively associated with quadriceps strength, regardless of HOA severity. • PhA could be one of the indicators of quadriceps strength in patients with HOA.

BackgroundThe amount of postoperative weight loss after bariatric surgery varies interindividually. The quality of the pre- and postoperative body composition is an important predictor of success. The aim of this study was to investigate the role of preoperative handgrip strength and phase angle (PhA) as predictors of sustained postoperative weight loss in order to assess the influence of body composition on the postoperative outcome after bariatric surgery.MethodIn a prospective cohort study, bioelectrical impedance and follow-up data of 198 patients after laparoscopic sleeve gastrectomy (SG;n = 68) and Roux-en-Y gastric bypass (GB;n = 130) were analyzed for a period of 36 months postoperatively.ResultsThe mean preoperative handgrip strength (31.48 kg, SD 9.97) correlates significantly with the postoperative body composition up to 24 months after surgery. Preoperative PhA, gender, size, and body weight influenced postoperative weight loss significantly. A significant correlation between preoperative PhA (mean 6.18°, SD 0.89°) and total weight loss (%TWL) was observed up to 3 months after SG (r = 0.31444,p = 0.0218) and up to 12 months after GB (r = 0.19184,p = 0.0467). The optimum cutoff for the prediction of a response of less than 50% excess weight loss was a preoperative PhA of 6.0°.ConclusionsThe preoperative handgrip strength confirmed its suitability for use as a predictor of postoperative body composition, whereas the preoperative PhA predicts postoperative weight loss after bariatric surgery. Further research is necessary to identify the role of these parameters for preconditioning.

This study aimed to determine the value of phase angle (PhA) in patients with chronic obstructive pulmonary disease (COPD) and pulmonary hypertension (PH) and its association with nutritional and functional parameters.A cross-sectional study of 77 patients under follow-up at the pulmonary outpatient clinic of a public hospital. Anthropometric measurements and functional assessments of physical and pulmonary capacity were performed, and a regular physical activity questionnaire was administered.The sample consisted of 38 patients with COPD (mean age, 63.8 ± 9.9 years; 68.4% female) and 39 patients with PH (mean age, 46.6 ± 14.4 years; 79.5% female). There was no difference in anthropometric measurements between patients with COPD and PH. Patients with COPD had mild to moderate limitations of pulmonary function, while patients with PH had only mild limitations (p 0.01). Although the median distance covered in the 6-minute walk test (6MWT) was different between the COPD and PH groups (p 0.05), it was considered adequate for these populations. Mean PhA was within the range considered adequate in patients with COPD (6.3°±1°) and PH (6.2°±0.8°) (p 0.05). In the statistical analyses, although the correlations were weak, adequate PhA correlated with fat free mass index, 6MWT, disease staging, forced vital capacity, and forced expiratory volume in the first second.The anthropometric profile of both patient groups was very similar, and PhA values were within the expected range. Despite weak correlations, PhA is a clinical component to be followed and investigated in patients with lung disease.

OBJECTIVE: We investigated the prevalence of micronutrient deficiencies and associated patient and disease-related risk factors in patients with chronic pancreatitis (CP).METHODS: We enrolled 115 consecutive CP outpatients. Micro-nutritional assessments included plasma levels of fat-soluble vitamins (A, D and E) and trace elements (magnesium and zinc). Bioelectrical impedance and muscle function tests were used to characterize the macro-nutritional status (sarcopenia and phase angle). Prevalence of micro-nutritional deficiencies was estimated and associated with a number of patient and disease characteristics including presence of exocrine pancreatic insufficiency (EPI) and diabetes mellitus. In an additional analysis, we explored the association between micronutrient levels and macro-nutritional status.RESULTS: The mean age of patients was 57.9 ± 13.0 years, 71% were men and 50% had an alcoholic aetiology. Vitamin D deficiency (22%) was the most common micronutrient deficit followed by zinc deficiency (20%) and magnesium deficiency (17%). Vitamin A deficiency (10%) and vitamin E deficiency (7%) were only seen in patients with EPI (P ≤ 0.03), while the presence of trace element deficits was associated with plasma albumin levels (P ≤ 0.006). Plasma zinc levels were decreased in sarcopenic patients (P < 0.001) and positively correlated to phase angle (coefficient 0.28; P < 0.001).CONCLUSION: Various micronutrient deficits were observed in CP outpatients, and associated risk factors were diverse and distinct for the individual nutrients. Taken together, our findings highlight the complexity of micronutrient assessment in patients with CP and emphasise the importance of simultaneous evaluation of plasma protein levels, inflammatory activity and macro-nutritional status.

The role of physical activity in anorexia nervosa (AN) treatment has been investigated. Muscle strength (MS) reflects physical condition and can predict AN patients' response to this novel treatment approach. This study was intended to find bioelectrical impedance analysis (BIA) parameters that predict AN patients' MS.The study included 42 AN patients and 42 healthy ones in the control group. BIA parameters that predict MS were assessed by dividing AN patients into groups by their hand grip strength test score (higher/lower than 22.5 kg).The highest accuracy for distinguishing AN subjects from the control group was achieved by cell membrane capacitance (AUC = 0.916), impedance at 200 kHz and 5 kHz ratio (AUC = 0.924), phase angle (PA) 5 kHz (AUC = 0.906) and PA 50 kHz (AUC = 0.919). The low MS group had significantly lower values of PA 50 kHz (mean: 4.03 ± 0.80° vs. 4.58 ± 0.65°;PA 50 kHz is the best BIA parameter to predict MS in AN patients. It could be useful for assessment before physical activity treatment application.

Background The bioelectric impedance analysis permits to estimate electrical parameters and body composition of subjects who are either apparently healthy or sick with different pathologies. The aim of this study is to individualize the analysis of body bioelectrical impedance parameters in newly diagnosed cancer children, by means of the bioelectrical impedance analysis for each age group, gender and cancer histological variety. Methods This retrospective cross-sectional study consisted of 43 pediatric patients with different histological varieties of cancer, ages from 2 to 17. The body electrical resistance and body capacitive electrical reactance were measured with the Bodystat 1500-MDD analyzer. From these two electrical parameters the body electrical impedance modulus and the body phase angle were calculated. Results The results showed that 93.02% of cancer children were outside reference rectangles according to age groups and gender were showed. The values of body capacitive electrical reactance (72.5%) and body phase angle (90.70%) of these patients were below the lower limits of their respective rectangles. These findings were noticeable for patients who had solid tumors. Conclusions The BIA is feasible to individualize body bioelectrical parameters and body bioelectric state in newly diagnosed cancer children and how differ from those in apparently healthy subjects, for the same age group and gender. Additionally, the tumor electrical properties may have a noticeable role in changes of body bioelectric-physiological parameters of these newly diagnosed cancer children.

Renewable energy sources integrated withconventional sources fed grid to meet the ongoing electricalenergy demands. This paper presents design of EnhancedPhase locked loop (EPLL) for single phase grid connectedtransformer less inverter. The knowledge of phase angle,frequency, voltage magnitude is under consideration tointegrate the solar PV to single-phase grid. It is required totrack exact utility voltage vector for reliable control of powerto the grid. The paper also presents Simulink modeling,analysis of Enhanced PLL and compares its performance withbasic phase locked loop (PLL) used.Index Terms: Enhanced phase locked loop (EPLL),Transformerless inverter, single phase grid connected