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Surely most chronobiologists believe circadian clocks are an adaptation of organisms that enhances fitness, but are we certain that this focus of our research effort really confers a fitness advantage? What is the evidence, and how do we evaluate it? What are the best criteria? These questions are the topic of this review. In addition, we will discuss selective pressures that might have led to the historical evolution of circadian systems while considering the intriguing question of whether the ongoing climate change is modulating these selective pressures so that the clock is still evolving.

Bituminous binder in asphalt mixture is exposed to the influence of aging, which is intensified during mixing and paving, as high temperature strongly accelerates the aging of bituminous binders. The aging of the binder is generally divided into short-term and long-term aging. The work focuses on comparing the properties of bitumen binders that differ in penetration value and aging level. All binders in the study are divided into these aging categories, and their properties are compared with the properties of unaged binders. The comparison of properties is carried out using basic empirical tests (penetration and softening point) as well as rheological tests (complex shear modulus and phase angle).

[Abstract] Phase angle (PhA) is a valuable tool for evaluating the nutritional and inflammatory status, which can accompany acute and severe disorders. PhA is a cellular health biomarker, whose value is particularly substantial due to the negative consequences of these situations in the pediatric population. Relevant literature was collected with the aim of comprehensively analysing the evidence on the association between an altered PhA can serve as a predictive-marker for mortality and poor-outcomes in at-risk-pediatric patients. Understanding this relationship could have significant implications for identifying high-risk individuals and implementing timely interventions. A systematic review with meta-analysis was conducted in the primary electronic databases from inception until January 2023. Overall, four studies with a total of 740 patients were eligible for our analysis. Evidence demonstrates that PhA is associated with nutritional status, reflecting undernutrition and changes in body composition related to illness. This review suggests that PhA can indeed be used as an indicator of nutritional status and a tool for predicting prognosis, including mortality and poor-outcomes, in hospitalized pediatric patients. A low PhA was associated with a significant mortality risk [RR:1.51;95%CI (1.22-1.88),p = 0.0002;I2 = 0%,(p = 0.99)] and an increased complications risk [OR:8.17;95%CI (2.44-27.4),p = 0.0007;I2 = 44%,(p = 0.18)]. These findings highlight the importance of taking a comprehensive approach to clinical nutrition, integrating multiple evaluation aspects to establish an accurate diagnosis and personalized therapeutic plans. While PhA emerges as a valuable tool for assessing the risk of malnutrition and as a prognostic-indicator for poor-outcomes in pediatric patients. Further future studies are needed to focus on investigating this relationship in larger and diverse population to strengthen the evidence base.

Producción Científica, Phase angle (PhA) has been evidenced to be a useful survival indicator and predictor of morbi-mortality in different pathologies, but not in psychogeriatric patients. The aim of this study was to evaluate the clinical utility of PhA as a prognostic indicator of survival in a group of institutionalized psychogeriatric patients. A survival study was conducted on 157 patients (46.5% dementia, 43.9% schizophrenia). Functional impairment stage, frailty, dependence, malnutrition (MNA), comorbidity, polypharmacy, BMI, and waist circumference were registered. Body composition was analyzed using a 50-kHz whole-body BIA; PhA was recorded. The association between mortality and standardized-PhA was evaluated through univariate and multivariate Cox regression models and ROC-curve. The risk of death decreased when Z-PhA, BMI, and MNA were higher. Mortality increases with age, frailty, and dependence. The risk of death was statistically significantly lower (56.5%) in patients with schizophrenia vs. dementia (89%). The Z-PhA cut-off point was −0.81 (Sensitivity:0.75; Specificity:0.60). Mortality risk was multiplied by 1.09 in subjects with a Z-PhA < −0.81, regardless of age, presence of dementia, and BMI. PhA presented a remarkable clinical utility as an independent indicator of survival in psychogeriatric patients. Moreover, it could be useful to detect disease-related malnutrition and to identify subjects eligible for an early clinical approach.

Background: Anemia is one of the common complications of diabetes and is associated with mortality. Phase angle (PhA), ratio of extracellular water to total body water (ECW/TBW) and skeletal muscle mass index (SMI) estimated by bioelectrical impedance analysis (BIA) have been used as prognostic indicators for various chronic diseases and frailty. We aimed to clarify the clinical significance of PhA, ECW/TBW and SMI for anemia in patients with diabetes. Materials and methods: The values of PhA, ECW/TBW and SMI were estimated by a portable BIA device and blood samples were collected in 371 Japanese patients with diabetes. The relationships of PhA, ECW/TBW and SMI with hemoglobin (Hgb) and hematocrit (Hct) were statistically evaluated. Results: In simple linear regression analysis, PhA and SMI were positively correlated with Hgb and Hct levels in total subjects, male subjects and female subjects. In contrast, ECW/TBW was negatively correlated with Hgb and Hct levels regardless of sex. Multivariate regression analysis showed that both PhA and ECW/TBW but not SMI independently contributed to Hgb and Hct levels after adjustment of clinical confounding factors in both males and females. Conclusions: PhA and ECW/TBW but not SMI were associated with levels of Hgb and Hct in patients with diabetes. Therefore, aberrant values of PhA and ECW/TBW suggest a risk of anemia in diabetic patients.

Phase angle (PhA) is a recently proposed marker of nutritional status in many clinical conditions. Its use in patients with obesity presents different critical concerns due to the higher variability of the two measured parameters (resistance, R, and reactance, Xc) that contribute to the determination of PhA. Controversial is the relation between PhA and BMI that might vary with graded levels of obesity due to the variation in fat and free fat mass. Obesity is frequently associated with metabolic, hepatic, cardiovascular and kidney diseases that introduce variations in PhA values, in relation to multimorbidity and severity degree of these diseases. It is reported that the improvement of clinical condition is associated with a positive change in PhA. Also, the treatment of obesity with weight loss might confirm this effect, but with different responses in relation to the type and duration of the intervention applied. In fact, the effect appears not only related to the percentage of weight loss but also the possible loss of free fat mass and the nutritional, metabolic and structural modifications that might follow each therapeutic approach to decrease body weight. We can conclude that the PhA could be used as marker of health status in patients with obesity supporting an appropriate weight loss intervention to monitor efficacy and fat free mass preservation.

Background: The impact of body composition (BC) abnormalities on COVID-19 outcomes remains to be determined. Objectives: We summarized the evidence on BC abnormalities and their relationship with adverse clinical outcomes in patients with COVID-19. Methods: A systematic search was conducted up until 26 September, 2022 for observational studies using BC techniques to quantify skeletal muscle mass (or related compartments), muscle radiodensity or echo intensity, adipose tissue (AT; or related compartments), and phase angle (PhA) in adults with COVID-19. Methodological quality of studies was assessed using the Newcastle-Ottawa Scale. A synthesis without meta-analysis was conducted to summarize the prevalence of BC abnormalities and their significant associations with clinical outcomes. Results: We included 62 studies (69.4% low risk of bias) with 12-1138 participants, except 3 studies with ≤490,301 participants. Using CT and different cutoff values, prevalence ranged approximately from 22% to 90% for low muscle mass, 12% to 85% for low muscle radiodensity, and 16% to 70% for high visceral AT. Using BIA, prevalence of high FM was 51%, and low PhA was 22% to 88%. Mortality was inversely related to PhA (3/4 studies) and positively related to intra- and intermuscular AT (4/5 studies), muscle echo intensity (2/2 studies), and BIA-estimated FM (2/2 studies). Intensive care unit (ICU) admission was positively related to visceral AT (6/7 studies) and total AT (2/3 studies). Disease severity and hospitalization outcomes were positively related to intra- and intermuscular AT (2/2 studies). Inconsistent associations were found for the rest of the BC measures and hospitalization outcomes. Conclusions: Abnormalities in BC were prevalent in patients with COVID-19. Although conflicting associations were observed among certain BC abnormalities and clinical outcomes, higher muscle echo intensity (reflective of myosteatosis) and lower PhA were more consistently associated with greater m

The use of predictive models can facilitate the inclusion of shear parameters in asphalt mixture evaluation and design processes. Unlike more extensively studied tension–compression models, the currently existing shear model, the Hirsch model, has unrealistic constants, particularly for the prediction of phase angle. Aiming at an improved predictive model in shear, this study employs a simple shear apparatus to experimentally analyse the linear viscoelastic properties of asphalt mixtures for road paving. Master curves were constructed and compared between different asphalt mixtures. Additionally, the test results were also analysed in the Black space and the Cole-Cole space. The dynamic shear response of asphalt mixtures was thereafter modelled on the basis of the Hirsch model. As the original model for phase angle prediction was found to be unrealistic, a particular focus in this study was put on identifying realistic empirical relationships for predicting the phase angle of asphalt mixtures in shear. More reliable shear test results of asphalt mixtures were used to calibrate the model, and extra test data were utilized to validate the calibrated model. It is indicated that the predictive model after calibration could deliver results of greatly improved accuracy, especially at the high-frequency and low-frequency ends. The analysis and modelling also leads to realistic empirical relationships for predicting the phase angle of asphalt mixtures in shear. The experimental verification confirms the good prediction accuracy of the calibrated model and proposed empirical relationships.

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.

High-frequency responsive capacitors with lightweight, flexibility, and miniaturization are among the most vital circuit components because they can be readily incorporated into various portable devices to smooth out the ripples for circuits. Electrode materials no doubt are at the heart of such devices. Despite tremendous efforts and recent advances, the development of flexible and scalable high-frequency responsive capacitor electrodes with superior performance remains a great challenge. Herein, a straightforward and technologically relevant method is reported to manufacture a carbon fabric membrane “glued” by nitrogen-doped nanoporous carbons produced through a polyelectrolyte complexation-induced phase separation strategy. The as-obtained flexible carbon fabric bearing a unique hierarchical porous structure, and high conductivity as well as robust mechanical properties, serves as the free-standing electrode materials of electrochemical capacitors. It delivers an ultrahigh specific areal capacitance of 2632 µF cm−2 at 120 Hz with an excellent alternating current line filtering performance, fairly higher than the state-of-the-art commercial ones. Together, this system offers the potential electrode material to be scaled up for AC line-filtering capacitors at industrial levels.

Objective: We aimed to investigate the correlation of phase angle (PhA) with other parameters (e.g., muscle mass/quality/strength and physical function), assess the prognostic relevance of pre-chemoradiotherapy (CRT) PhA, and suggest a reference value of PhA in Asian patients with head and neck cancer (HNC). Research Methods & Procedures: Ninety-six patients with HNC who underwent CRT were divided into two groups, maintained-PhA group and low-PhA group, according to the PhA 25th percentile values by sex. Pretreatment PhA was measured using direct segmental multi-frequency bioelectrical impedance analysis, and muscle quality was assessed using echo intensity in ultrasound images. Correlation of PhA with other parameters was investigated, and between-group differences with respect to adverse events, treatment interruption, and 3-year survival were assessed. Results: PhA showed a positive correlation with isometric knee extension force (R = 0.710), handgrip strength (R = 0.649), skeletal muscle mass index (R = 0.620), and maximum gait speed (R = 0.543) (P < 0.001). PhA showed a negative correlation with echo intensity (R = −0.439) and five times sit-to-stand test (R = −0.505) (P < 0.01). The low-PhA group had a higher incidence of severe anemia (52% in low-PhA vs. 17% in maintained-PhA), aspiration (17% vs. 1%), radiotherapy interruption (17% vs. 3%), and poor 3-year survival (47% vs. 81%) than the maintained-PhA group (P < 0.05). Conclusion: PhA was correlated with muscle mass/quality/strength, and physical function. Low PhA was associated with severe adverse events, treatment interruption, and shorter survival. These findings suggested that 4.6° for men and 4.0° for women may be useful as prognostic reference values in Asian patients with HNC.

Small-scale cohesive-zone models based on potential functions are expected to be consistent with the important features of linear-elastic fracture mechanics (LEFM). These include an inverse-square-root K-field ahead of a crack, with the normal and shear stresses stresses being proportional to the mode-I and mode-II stress-intensity factors, KI and KII, the work done against crack-tip tractions being equal to (K2I + K2II)/E , where E is the appropriate modulus, and failure being controlled by the toughness. The use of an LEFM model also implicitly implies that the partition of the crack-tip work into shear and normal components is given by a phase angle defined as ψκ = tan-1(KII / KI). In this paper, we show that the partition of crack-tip work in a cohesive-zone model is consistent with LEFM if the normal and shear deformations across an interface are uncoupled. However, we also show that this is not the case for coupled cohesive laws, even if these are derived from a potential function. For coupled laws, LEFM cannot be used to predict the partition of work at the crack tip even when the small-scale requirements for LEFM conditions being met; furthermore, the partition of the work may depend on the loading path. This implies that LEFM cannot be used to predict mixed-mode fracture for interfaces that are described by coupled cohesive laws, and that have a phase-angle-dependent toughness.

Laboratory performance testing of the phase angle of asphalt concrete (AC) mixtures is often expensive and requires enormous human effort and time. To circumvent this problem, several regression-based methods have been proposed in the literature to model the phase angle behavior of AC mixtures using various approaches. However, these methods impose strict assumptions on the underlying relationship between phase angle and its corresponding covariates as well as how well and accurately these covariates are measured, restricting us from fully analyzing the predictive capability of any modeling method. To this end, this study proposed an alternative approach for modeling the phase angle characteristics of AC mixtures based on a recurrent neural network (RNN) that inherently and implicitly captures the effects of covariates. This approach is suitable to model the sequential nature of data recorded in laboratory testing where phase angle testing was repeated for a set of six loading frequencies forming a recurrent pattern. The proposed RNN model (P-RNN) was applied separately to wearing and base course mixtures by considering the historical values of phase angle as input and to predict its value for the next loading frequency, keeping temperature as a constant. To demonstrate the superiority of the proposed approach, the P-RNN model is compared with other competing models from the literature, and the results reveal superior performance of the P-RNN model.

Selection of asphalt concrete (AC) mixtures with proper knowledge of its phase angle characteristics is critical in designing flexible pavements and ensuring the maximum service life of pavements. To achieve this purpose, laborious and expensive laboratory testings are frequently performed, and the results are implied to field. To overcome this problem, models (mathematical or machine learning) are developed to predict the phase angle of AC mixtures. However, the complex and non-linear relationship of phase angle with its independent variables is hard to capture using simple mathematical (or statistical) models. As such, this study proposes a data-driven model based on Convolutional Neural Network (CNN) to capture and predict the phase angle behaviour of AC mixtures. Twenty-three AC mixtures are prepared in laboratory consisting of varying gradations, binder grades, and mix types to perform phase angle testing. The proposed modelling framework, trained using the dataset obtained from laboratory testing, captures 90% of the variance in the test data, which is a significant improvement as compared with other machine learning models as well as linear regression. The proposed model has the capability to capture the non-linearity associated with AC mixtures and can be used by transport agencies and practitioners as a surrogate to tedious laboratory testing.

In-orbit calibrations of space instruments are often necessary to ensure the accuracy of the measurements. The Moon provides a target with very predictable characteristics. In this report, the opportunities to perform in-orbit lunar calibrations of the MicroCarb instrument are evaluated and a procedure for conducting the Mission Planning for these calibrations is developed. Through modeling the spacecraft in its orbit, simulations show that continuous observation sequences of up to 48 minutes can be expected each lunation. The variability of the optical properties of the Moon during an opportunity is related to the orientation of the plane of the orbit of the spacecraft with respect to the cone with axis the Moon-Sun direction and apex the center of the Moon that contains the spacecraft. Choosing a value of the phase angle (Sun-Moon-Spacecraft angle) around −20 degrees to plan the lunar calibrations allows to minimize the variations of apparent radiance of the Moon during the observation. The results make it possible to refine the choice of the best moments to plan the lunar calibrations. This also allows the satellite operations team to anticipate the planning of lunar calibrations on the scale of several months., Kalibreringar i omloppsbana för rymdinstrument är ofta nödvändiga för att säkerställa mätningarnas noggrannhet. Månen utgör ett kalibreringsmål med mycket förutsägbara egenskaper. I denna rapport utvärderas möjligheterna att utföra månkalibreringar i omloppsbana för MicroCarb-instrumentet och ett förfarande för genomförande av uppdragsplanering för dessa kalibreringar har utvecklats. Genom att modellera rymdfarkosten i sin bana visar simuleringar att kontinuerliga observationssekvenser på upp till 48 minuter kan förväntas varje månvarv. Variationen hos de optiska egenskaperna för månen under ett tillfälle är relaterad till orienteringen av rymdfarkostens plan i förhållande till konen med axeln för månen-solens riktning. Att välja ett värde för fasvinkeln (Sun-Moon-Spacecraft-vinkel) på runt −20 grader vid planering av månkalibreringarna gör det möjligt att minimera variationerna i månens strålning under observationen. Resultaten gör det möjligt att förfina valet av de bästa tidpunkterna för månkalibreringarna. Detta gör det också möjligt för satellitoperationsteamet att förutse planeringen av månkalibreringar flera månader framåt.

Electrical impedance myography (EIM) is an evaluation technique for skeletal muscles that uses electrical impedance technology. Recent reviews have shown that EIM is useful as a method to assess changes in skeletal muscle quality and quantity with aging. These may be utilized for functional changes in inflammatory skeletal muscles, such as disease and operation. In this report, the impedance parameters using EIM present perioperative skeletal muscle changes in patients after cardiac surgery. In addition, we will describe the efficacy of EIM in skeletal muscle dysfunction due to inflammation or disease. This study aimed to elucidate the efficacy of EIM in acute inflammation-associated skeletal muscle dysfunction.

Objective: This study aimed to examine associations between phase angle (PhA) and incident cardiovascular disease (CVD) morbidity and mortality in a healthy Danish subpopulation free of major chronic diseases. Methods: A random subset (n = 2601) of adult men and women born in 1922, 1932, 1942, and 1952 and examined in 1987 and 1988 were included, and followed over 24 y during which 643 men and 570 women developed CVD. Measures at baseline included age, weight, height, whole-body bioimpedance, from which PhA was calculated, and information on lifestyle, obtained by a self-administered questionnaire. The association between PhA and incident CVD was assessed by Cox proportional hazard model with age as the underlying time scale and with additional adjustment for covariates. To explore nonlinear associations, all results were presented using restricted cubic splines, with the median value of PhA as the reference. Results: PhA was lower among women who later developed CVD than among women who did not (6.3 vs. 6.0; P < 0.001). The highest risk of CVD was observed at the 5th percentile (hazard ratio: 1.33; 95% confidence interval, 1.11-1.60). Among men, PhA was not significantly associated with risk of CVD (7.1 vs. 7.0; P = 0.246). Conclusions: Among apparently healthy Danish men and women, a lower PhA value was associated with a higher incidence of CVD over 24 y, also after adjusting for potential confounders, and particularly among women. These findings may encourage the future use of PhA as an additional index in predicting CVD. However, more studies are needed to confirm our results. (c) 2021 Elsevier Inc. All rights reserved.

Objectives: Infectious morbidity is the most common and costly among all surgery-related complications, and infections by multidrug-resistant microorganisms (MDR) are associated with poor outcomes. Derangements of body composition is a recognized risk factor for infections. The aim of this study was to investigate the potential association between specific traits of body composition and the risk of having MDR-related infections. Methods: This was a prospective study with patients scheduled for major abdominal surgery for gastrointestinal cancer. Bioimpedance vector analysis (BIVA), a reliable tool for body composition assessment, was performed the day before the operation. Postoperative complications were collected focusing on resistance patterns and site of infection. Patterns of resistance were compared with BIVA parameters. Results: Data from 182 patients suffering from pancreatic (n = 76, 41.7%), rectal (n = 38, 20.9%), gastric (n = 31, 17%), or hepatic (n = 37, 20.3%) malignancy were collected. Overall complications occurred in 108 patients (59%), and in 45 patients (28%) bacterial infections were proven at culture. Of these, 15 (8%) were multidrug-sensitive (MDS), 38 MDR, and 2 extended drug-resistant (XDR) infections. The standardized phase angle measured (SPA) at BIVA was significantly lower in the MDR/XDR infections (–0.02 ± 1.20) than for no infection/MDS (0.56 ± 1.53; P = 0.029). A multivariate analysis showed that SPA was the only independent variable for MDR/XDR infections with an odds ratio of 3.057 (95% confidence interval, 1.354–6903; P = 0.007). The predictive ability of SPA revealed an area under the receiver operating characteristic curve of 0.662, with an optimal threshold of –0.3. Conclusions: In surgical cancer patients, preoperative value of SPA lower than -0.3 is associated with the outbreak of MDR bacterial infections.

Background: A poor body composition, often found in elderly patients, negatively impacts perioperative outcomes. We evaluated the effect of a perioperative nutritional protocol (NutriCatt) on body composition and clinical outcomes in a cohort of elderly patients undergoing colorectal surgery in a high-volume center adopting the ERAS program. Methods: 302 out of 332 elderly (>75 years) patients from 2015 to 2020 were identified. Patients were divided according to their adherence, into “NutriCatt + ERAS” (n = 166) or “standard ERAS” patients (n = 136). Anthropometric and bioelectrical impedance analysis data were evaluated for NutriCatt + ERAS patients. Complications, length of hospital stay (LOS), and other postoperative outcomes were compared between both groups. Results: In NutriCatt + ERAS patients, significant improvements of phase angle (pre-admission vs. admission 4.61 ± 0.79 vs. 4.84 ± 0.85; p = 0.001; pre-admission vs. discharge 4.61 ± 0.79 vs. 5.85 ± 0.73; p = 0.0002) and body cell mass (pre-admission vs. admission 22.4 ± 5.6 vs. 23.2 ± 5.7; p = 0.03; preadmission vs. discharge 22.4 ± 5.6 vs. 23.1 ± 5.8; p = 0.02) were shown. NutriCatt + ERAS patients reported reduced LOS (p = 0.03) and severe complications (p = 0.03) compared to standard ERAS patients. A regression analysis confirmed the protective effect of the NutriCatt protocol on severe complications (OR 0.10, 95% CI 0.01–0.56; p = 0.009). Conclusions: The NutriCatt protocol improves clinical outcomes in elderly patients and should be recommended in ERAS colorectal surgery.

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 C

Objective Phase angle (PhA), by bioelectrical impedance analysis, has been used in patients with several diseases; however, its prognostic value in patients with gastrointestinal and hepatobiliary–pancreatic (HBP) cancer is unclear. The present study aimed to investigate the impact of PhA on postoperative short-term outcomes and long-term survival in these patients. Research Methods & Procedures This retrospective study reviewed data of 501 patients with gastrointestinal and HBP cancers who underwent first resection surgery and divided the data into the following groups according to the preoperative PhA quartile values by sex: high-PhA group with the highest quartile (Q4), normal-PhA group with middle quartiles (Q3 and Q2), and low-PhA group with the lowest quartile (Q1). Preoperative nutritional statuses, postoperative short-term outcomes during hospitalization, and 5-year survival between three groups were compared. Cox proportional hazard models were used to evaluate the prognostic effect of PhA. Results PhA positively correlated with body weight, skeletal muscle mass, and handgrip strength, and negatively correlated with age and C-reactive protein levels. The low-PhA group showed a high prevalence of malnutrition (48%) than normal-PhA (25%), and high-PhA (9%) (P < 0.001). The incidence of postoperative severe complications was 10% in all patients [14% in low-PhA, 12% in normal-PhA, and 4% in high-PhA (P = 0.018)]. The incidence of prolonged postoperative high care unit or/and intensive care unit stays was 8% in all patients [16% in low-PhA, 8% in normal-PhA, and 2% in high-PhA (P < 0.001)]. The 5-year survival rate was 74% in all patients [68% in low-PhA, 74% in normal-PhA, and 79% in high-PhA (P < 0.001)]. The multivariate analysis demonstrated that a low-PhA group was an independent risk factor for mortality (hazard ratio, 1.99; 95% confidence interval 1.05–3.90; P = 0.034). Conclusion PhA is a useful short-term and long-term postoperative prognostic marker fo

The phase angle (AF) is currently used to establish cellular integrity, which is why it has been used to recognize body cell mass and is determined as a nutritional indicator in children and adults. Objective. Relate the values obtained from AF with variables of body composition and muscle strength in athletes. Methodology. Quantitative approach of a non-experimental type and with a cross-sectional correlational scope, as well as the type of data that were taken were from 129 athletes, 101 (78.3) men and 28 (21.7%) and women, to whom body composition (through InBody 770), and muscle strength (T-force, model TF-100) were taken. Results. A statistically significant but weak correlation is obtained between the phase angle and the percentage (%) of fat mass and be-tween the mean forces, which are inverses. Likewise, a significant and moderate statistical correla-tion was found between phase angle and kilograms (Kg) of skeletal muscle mass, load (kg) maximum force, Average Power, maximum power and total body water and phase angle which are positive., El ángulo de fase (AF), actualmente es utilizado para establecer la integridad celular, por lo que ha sido empleada para reconocer la masa celular corporal y es utilizada como un indi-cador a nivel nutricional en los niños y adultos. Objetivo. Relacionar los valores obtenidos del AF con variables de composición corporal y fuerza muscular en deportistas. Metodología. Enfoque cuantitativo de tipo no experimental y con un alcance correlacional de corte transversal, así mismo el tipo de datos que se tomaron fueron de 129 deportistas, 101 (78,3) hombres y 28 (21,7%) y mujeres, a los que se les tomó composición corporal (a través del InBody 770), y fuerza muscular (T-force, modelo TF-100). Resultados. Se obtiene una correlación estadísticamente significativa pero débil entre el ángulo de fase y porcentaje (%) de masa grasa y entre fuerza media las cuales son inversas. Así mismo, se encontró una correlación moderada y estadística significativa entre án-gulo de fase y kilogramos (Kg) de masa musculo esquelética, la carga (kg) fuerza máxima, Potencia Media, potencia máxima y agua corporal total y ángulo de fase las cuales son positivas.

Postprint (author's final draft)

Crack root rotation is a measure of deviation from clamped boundary conditions of region in front of the crack tip. The root rotation depends on the shear force and bending moment acting at the crack tip. Such rotation significantly affects the compliance and energy-release rate. Crack root rotation analysis of Single Cantilever Beam (SCB) sandwich specimens is presented here. Closed-form solutions for the root rotation angle obtained from the foundation analysis are compared to finite element analysis (FEA) predictions. The derived expressions closely match for a range of sandwich configurations. An expression for the energy-release rate, derived from the foundation analysis was found to agree with FEA predictions over a large range of face-to-core modulus ratios. Energy-release rate and mode mixity phase angle increased with decreasing crack length due to the transverse shear effects. At longer crack lengths, both energy-release rate and phase angle reached a value independent of crack length. The foundation model is used to derive a simple expression for the offset crack length for the SCB sandwich fracture test. It is shown that the obtained formulation agrees closely well with both numerical and experimental values. In addition, SCB fracture tests performed using an in-house built translatable rig showed close relation to both analytical and numerical compliance results.

The single cantilever beam sandwich specimen has been proposed, as a fracture test standard for mode I peel loading. Critical parameters, including specimen dimensions, determine whether the crack propagates along the face/core interface in mode I during the fracture test. This paper outlines a parametric study based on a numerical method to examine local mode mixity conditions for a wide array of sandwich systems by varying several geometrical and material parameters. The thickness and modulus of the face sheet were seen to influence the mode mixity for most sandwich systems. Core Poisson’s ratio was shown to influence the local mode mixity and has the capability of driving the crack along the interface or into the core. The effect of the intact specimen length was analyzed and presented from a mode mixity perspective based on various elastic foundation modulus expressions. Reinforcement of the single cantilever beam specimen with stiff layers was also investigated numerically and compared with a similar analysis in the literature. The analysis presented in this paper shows that, despite reducing the global shear component, the local mode mixity condition deviated away from the mode I regime for several sandwich specimens. An appropriate foundation model along with a minimum loading rod length was one of the recommendations provided from the analyses, which may supplement the ASTM International standardization efforts.

DevTMF

The decohesion of coatings, thin films, or layers used to protect or strengthen technological and structural components causes the loss of their functions. In this paper, analytical, computational, and semi-analytical 2D solutions are derived for the energy release rate and mode-mixity phase angle of an edge-delamination crack between a thin layer and an infinitely deep substrate. The thin layer is subjected to general edge loading: axial and shear forces and bending moment. The solutions are presented in terms of elementary crack tip loads and apply to a wide range of material combinations, with a large mismatch of the elastic constants (isotropic materials with Dundurs’ parameters −1≤α≤1 and −0.4≤β≤0.4 ). Results show that for stiff layers over soft substrates ( α→1 ), the effects of material compressibility are weak, and the assumption of substrate incompressibility is accurate; for other combinations, including soft layers over stiff substrates ( α→−1 ), the effects may be relevant and problem specific. The solutions are applicable to edge- and buckling-delamination of thin layers bonded to thick substrates, to mixed-mode fracture characterization test methods, and as benchmark cases.

Background: Patients with primary neuromuscular disease have reduced muscle mass, and use of body mass index to assess nutritional status and body composition can therefore be questioned. Dual emission X-ray absorptiometry (DXA) can estimate muscle mass, but is not always readily available. Bioimpedance is a simple, portable and "easy to use" method for the assessment of body composition. Objectives: To assess muscle mass by DXA in 143 patients with primary neuromuscular disease and validate three bioimpedance devices; Impedimed SFB7, (BISIMPEDIMED), Xitron4200 (BISXITRON) and Tanita MC180MA (MFBIATANITA). Methods: Body composition was assessed by DXA in 143, by BISIMPEDIMED in 116, by MFBIATANITA in 104 and by BISXITRON in 35 patients. Results: Muscle mass assessed by DXA, and phase angle (PhA) were below reference values in all female and 96% of male patients. BISIMPEDIMED underestimated muscle mass by 6.5±14.2 kg (p < 0.001), but this could be corrected after exclusion of resistance (Ri) values > 3500 Ohm (p = 0.84). MFBIATANITA over-estimated muscle mass by 30.8±9.1 kg (p < 0.001) with systematic bias, whereas BISXITRON was in agreement with DXA, and without systematic bias. Muscle mass was strongly correlated to PhA (rPEARSON = 0.75, p < 0.01). Conclusion: Patients with primary neuromuscular disease have proportionally more fat and less muscle mass than the population in general, despite normal BMI. Muscle mass can be assessed by bioimpedance in these patients, but performance and bias depends on device. Phase angle by bioimpedance correlates to muscle mass, and could therefore potentially be used a surrogate measure of muscle mass during follow up.

BackgroundAuditory steady-state response (ASSR) paradigms have consistently demonstrated gamma band abnormalities in schizophrenia at a 40-Hz driving frequency with both electroencephalography (EEG) and magnetoencephalography (MEG). Various time-frequency measures have been used to assess the 40-Hz ASSR, including evoked power, single trial total power, phase-locking factor (PLF), and phase-locking angle (PLA). While both EEG and MEG studies have shown power and PLF ASSR measures to exhibit excellent test-retest reliability in healthy adults, the reliability of these measures in patients with schizophrenia has not been determined.MethodsASSRs were obtained by recording EEG data during presentation of repeated 20-Hz, 30-Hz and 40-Hz auditory click trains from nine schizophrenia patients (SZ) and nine healthy controls (HC) tested on two occasions. Similar ASSR data were collected from a separate group of 30 HC on two to three test occasions. A subset of these HC subjects had EEG recordings during two tasks, passively listening and actively attending to click train stimuli. Evoked power, total power, PLF, and PLA were calculated following Morlet wavelet time-frequency decomposition of EEG data and test-retest generalizability (G) coefficients were calculated for each ASSR condition, time-frequency measure, and subject group.ResultsG-coefficients ranged from good to excellent (> 0.6) for most 40-Hz time-frequency measures and participant groups, whereas 20-Hz G-coefficients were much more variable. Importantly, test-retest reliability was excellent for the various 40-Hz ASSR measures in SZ, similar to reliabilities in HC. Active attention to click train stimuli modestly reduced G-coefficients in HC relative to the passive listening condition.DiscussionThe excellent test-retest reliability of 40-Hz ASSR measures replicates previous EEG and MEG studies. PLA, a relatively new time-frequency measure, was shown for the first time to have excellent reliability, comparable

BACKGROUND: Measures of skeletal muscle function decline at a faster rate with ageing than do indices of skeletal muscle mass. These observations have been attributed to age-related changes in muscle quality, another functional determinant separate from skeletal muscle mass. This study tested the hypothesis that improved predictions of skeletal muscle strength can be accomplished by combining clinically available measures of skeletal muscle mass and quality. METHODS: The participants included 146 healthy adult (age ≥ 18 years, range 18-77 years; X ± SD 47 ± 17 years and body mass index 16.5-51.8 kg/m2 ; 27.7 ± 6.2 kg/m2 ) men (n = 60) and women (n = 86) in whom skeletal muscle mass was estimated as appendicular lean soft tissue (LST) measured by dual-energy X-ray absorptiometry and skeletal muscle quality as bioimpedance analysis-derived phase angle and B-mode-evaluated echogenicity of mid-thigh skeletal muscle. Strength of the right leg and both arms was quantified as knee isokinetic extension and handgrip strength using dynamometers. The statistical significance of adding phase angle or echogenicity to strength prediction multiple regression models that included extremity-specific LST and other covariates (e.g. age and sex) was evaluated to test the study hypothesis. RESULTS: Right leg LST mass alone was significantly (P < 0.0001) correlated with isokinetic right leg strength (R2  = 0.57). The addition of segmental phase angle measured in the right leg at 50 kHz increased the R2 of this model to 0.66 (P < 0.0001); other phase angle frequencies (5 and 250 kHz) did not contribute significantly to these models. Results were similar for both right and left arm handgrip strength prediction models. Adding age and sex as model covariates increased the R2 values of these models further (e.g. right leg strength model R2 increased to 0.71), but

OBJECTIVES: Myotonic dystrophy type 1 (DM1) is an inherited muscle disorder characterized by slowly progressive weakness due to muscle degeneration. The Muscular Impairment Rating Scale (MIRS) is validated to assess clinical muscle severity of patients with DM1, although the scale is not sensitive enough to assess disease progression in time intervals fit for clinical trials. The aim of this study was to analyze bioelectrical whole body and arm segmental parameters in patients with DM1 to explore a correlation between bioelectrical impedance analysis (BIA) parameters and disease stage. METHODS: Forty patients with DM1 were enrolled in a cross-sectional study. In all patients, MIRS, handgrip strength (HGS), and BIA were assessed. A Kruskal-Wallis test was used to assess the difference in continuous variables according to MIRS. Correlation between BIA values and HGS were made by Pearson's coefficient analysis. A linear regression analysis was performed. RESULTS: Eighteen of 40 patients were men (45%). The median age of the cohort was 42 y (30-58 y). Four patients (10%) were classified as MIRS 1; 20 (50%) MIRS 2; 11 (27.5%) MIRS 3; and 5 (12.5%) as MIRS 4. A correlation was observed between phase angle and MIRS (P = 0.0001). MIRS correlated with other BIA values such as resistance, impedance ratio, and capacitance (P = 0.005, P = 0.0001, P = 0.0006, respectively). At linear regression analysis, segmental resistance, phase angle, impedance ratio, and capacitance of both arms significantly correlated with HGS. CONCLUSIONS: Results from the study support the use of BIA as a suitable procedure for staging DM1 muscle involvement and as a measure of muscle disease outcome, in clinical practice and in clinical trial design of therapeutic drugs.

Hospital malnutrition is still underestimated among physicians, even in internal medicine settings. This is a cross-sectional study, aiming to estimate the risk, the prevalence and the impact of malnutrition in an Internal Medicine and Gastroenterology Department of a large Italian hospital (Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome). Patients were evaluated within 72 h from admission according to Nutritional Risk Screening-2002 (NRS-2002) and European Society for Clinical Nutrition and Metabolism (ESPEN) Criteria. Anthropometric, laboratory tests and Bioelectrical Impedance Analysis (BIA) derived phase angle were also performed. Length of hospital stay (LOS) and in-hospital mortality were collected. Univariate and multivariate analyses were conducted to correlate nutritional status with LOS and hospital mortality. In 10 months, 300 patients were enrolled: male patients were 172 (57.3%); mean age was 63.7 (± 17.6). At admission, 157 (52.3%) patients were at risk of malnutrition; 116 (38.7%) were malnourished. Malnourished patients had a mean LOS of 11.5 (± 8.0) days, not-malnourished 9.4 (± 6.2) days (p < 0.05). In-hospital mortality did not significantly differ between the two groups. Multivariate analysis shows that both malnutrition (p = 0.04; 95% CI 0.03–3.41) and phase angle (p = 0.004; 95% CI − 1.92 to − 0.37) independently correlate with LOS. In an Internal Medicine and Gastroenterology Department, over half (52.3%) of the patients were found at risk of malnutrition, and over a third (38.7%) were malnourished at hospital admission. Malnutrition and BIA-derived phase angle are independently associated with LOS. ESPEN Criteria and phase angle could be performed at admission to identify patients deserving specific nutritional support.

Objective: To investigate whether patients' altered body composition (measured with bioimpedentiometry), due to a poor nutritional status, predicts the incidence of no residual disease at primary debulking and the risk of complications in patients with newly-diagnosed advanced epithelial ovarian cancer (EOC). Methods: Data regarding patients with newly-diagnosed stage IIIC-IV EOC undergoing elective nutritional assessment between December 2016 and March 2017, were prospectively collected. Bioelectrical impedance analysis (BIA) with measurement of BIA-derived phase angle [PhA] at 50 KHz, was accomplished. Only patients with disease which was considered resectable at staging laparoscopy were submitted to open primary cytoreduction. The rate of residual tumor (RT) = 0 and the incidence of complications were assessed. Results: Seventy patients were included. Fifty-two of them were submitted to primary cytoreduction (74.3%) and 48 (68.6% of the entire cohort, 92.3% of those who underwent primary debulking) had RT = 0 at the end of surgery. Median values of PhA were significantly lower in patients with RT > vs. =0 (4.7, range: 3.6–5.8 vs. 5.3, range: 4.2–6.8; p = 0.001). Twenty-four (out of the 52 operated) patients (46.2%) developed at least one complication. PhA was significantly lower in patients with vs. without complications (5, range: 3.6–6.4, vs. 5.4, range 4.5–6.8; p = 0.03). After multivariable analysis, Fagotti score and PhA were the only independent predictors of residual disease (OR:13.56; 95%CI:1.33–137.6; p = 0.027 and 9.24; 1.16–73.43; p = 0.036, respectively) and of any complication (OR:4.9;95%CI:1.17–20.6; p = 0.03 and 7.27; 1.45–36.4; p = 0.01, respectively). Conclusions: Derangement of body composition (likely due to disease-related malnutrition) expressed as a low phase angle, is an independent predictor of residual disease and peri-operative complications at the time of upfront cytoreduction for advanced EOC.

Sandwich composites marked by their characteristic high stiffness to weight ratio have received wide attention from various industrial sectors for weight critical applications. Sandwich constructions invariably comprise of different materials with distinct material properties, and are prone to peculiar failure modes. A critical and most common damage mode is face/core debonding (or disbonding). Debonds can occur due to several reasons - insufficient wetting of face sheet and core during the production process, blunt body impacts, tool drop or by prolonged exposure to in-service loads. The presence of a debond compromises the safety of the structure, as lack of adhesion between face sheet and core in a sandwich undermines the integrity of the entire structure. Nowadays, structures are pushed close to their performance limits leading to significant reduction of built-in reserve margins. Therefore, from the design and analysis perspective of sandwich structures, adequate tools are necessary for damage assessment. In order to assess the critical strain energy release rate of the face/core interface or fracture toughness, accurate methodologies need to be developed. The aim of this Thesis is to develop robust fracture mechanical based tools to characterize face/core debonds. Primarily, the focus was laid on fracture based test methods to assess the strength of the sandwich interface such as the Single Cantilever Beam (SCB) and the Double Cantilever Beam loaded with Uneven Bending Moments (DCB-UBM). A parametric study is conducted to analyze the SCB sandwich specimen from a mode mixity perspective based on the numerical mode-mixity method - Crack Surface Displace-ment Extrapolation (CSDE) method. For a wide array of sandwich systems it was shown that despite conforming to the existing sizing study, mode-mixity deviate away from mode I conditions during a SCB test. Recommendations are laid out based on the modelled results to ensure that the debonding occurs under mode

It is possible to identify certain characteristics of geostationary satellites by studying their photometry. This paper reviews some of the technical problems and methodologies concerning photometry of satellites, as well as their identification by photometric characteristics. The existing methods of identifying geostationary satellites using photometry are also summarized. The present Database of photometric and dynamic characteristics of the GSS, additional information, simplifying the input of the inverse problem  all this allows modern methods to identify unknown GSS with a probability up to 80%.

The bioimpedance is a method used to estimate humans and animals body composition, characterized by determining the value of the phase angle. This study aimed to estimate the fish condition through electrical bioimpedance technique and evaluate the performance of Nile tilapia grown in sewage water treated with the addition of probiotic (Bacillus licheniformis, Bacillus cereus and Bacillus subitillis and yeast - Saccharomyces cerevisiae and boulardi) in diets. For the experiment, 360 fingerlings were used with initial average weight of 2.91 ± 0.37 g and initial average length of 3.30 ± 0.27 cm, distributed in a completely randomized design with three treatments and six repetitions of 20 fish each. Treatments consisted of: PRO1 - fish grown in clean water; RO2 - fish grown in wastewater; PRO3 - fish grown in wastewater + probiotic added to the feed. All animals were fedto apparent satiety. Tilapia that were submitted to the health challenge (wastewater) presented phase angle less than 15°. Fulton´s K value was higher for the group treated with sewage water. The wastewater does not present conditions for a good crop and a good development of the fish, regardless the probiotic supplementation and the measurement method of health status used. The probiotic strains did not led to an improvement of fish performance and survival., A bioimpedância é um método utilizado para estimar de composição corporal em humanos e animais, caracterizado pela determinação do valor do ângulo de fase. Objetivou-se estimar a condição dos peixes por meio da técnica de bioimpedância elétrica e avaliar o desempenho de tilápias-do-nilo cultivadas em água de esgoto doméstico tratado com a adição de probiótico (Bacillus licheniformis, Bacillus cereus e Bacillus subitillis e leveduras –Saccharomyces cerevisiae e Saccharomyces boulardi) em rações. Foram utilizados 360 alevinos, com peso médio inicial de 2,91 ± 0,37 g e comprimento médio inicial 3,30 ± 0,27 cm, distribuídos em delineamento inteiramente casualizado, com três tratamentos, seis repetições de 20 peixes. Os tratamentos consistiram de: PRO1 - peixes cultivados em água tratada; RO2 - peixes cultivados em água residuária,; PRO3 - peixes cultivados em água residuária + probiótico adicionado na ração. Todos alimentados até a aparente saciedade. As tilápias que estavam submetidas ao desafio sanitário (água residuária) apresentaram ângulo de fase menor que 15°. O K de Fulton foi superior no grupo de peixes de água de esgoto doméstico tratado. A água residuária não apresenta condições para um bom cultivo e um bom desenvolvimento dos peixes, independentemente do uso de probiótico e do método de aferição do estado de saúde utilizado. As cepas probióticas não promoveram melhorias no desempenho desses peixes e nem na sobrevivência.

A three-dimensional unsteady Euler code for the analysis of Active Flap Control (AFC) has been developed in this study based on an advanced CFD (Computational Fluid Dynamics) code for the full configuration of helicopters. The effect of phase angle and geometric position of AFC on Blade-Vortex Interaction (BVI) noise is analyzed by combining the new CFD code with an acoustic code based on the Ffowcs Williams and Hawkings (FW-H) equation. As a result, a simple model is proposed to understand the effect of flap phase angle on BVI noise and 3D calculations by the present method confirm that the model properly works. The prediction of the effect of flap phase angle by the present method is remarkably improved by applying the understandings derived from the simple model. A quantitative noise reduction of 5.62 dB is obtained at the flap phase angle of 60 deg and noise signal strongly propagates almost downward in the present condition. The prediction of flap position effect shows that more effective BVI noise reduction can be achieved by the flap at the outer position with well-adjusted phase. When the flap is located near the blade tip, the merger between outer flap vortex and tip vortex can change the tip vortex strength and the blade surface pressure in the BVI condition. As the flap location moves inward, the sudden change of BVI noise reduction mechanism happens, which needs more discussion for the understandings., ヘリコプタ全機周りの流れ場を解析する3次元非定常オイラー・コードをベースに、ブレード／渦干渉(Blade-Vortex Interaction: BVI)騒音低減用のアクティブ・フラップ制御(Active Flap Control: AFC)を解析するコードを開発し、Ffowcs Williams and Hawkings(FW-H)の式に基づく音響解析コードと組み合わせることで、AFCの重要な2つのパラメータであるフラップの位相角と取り付け位置が騒音に及ぼす影響を解析した。ここで、位相角の影響を容易に把握するための簡易的なモデルを提案し、そこから得られる知見を適用することで、実験値の予測を格段に改善できることを示した。また、ここで用いた特定の条件では、位相角60度のとき5.62dBの騒音低減効果が得られた。フラップ位置の影響については、より翼端に近い位置に配置されたフラップを適正な位相角で作動させることが騒音低減に有効であることを示した。また、フラップを翼端に近い位置に配置した場合、フラップの外端から発生するフラップ渦がブレードの翼端渦と融合する現象が捉えられた上、それが翼端渦の強度に影響を及ぼしてBVIの起こる瞬間にブレード上圧力変動を増加させることを確認した。さらに、フラップ位置を内側から外側に移動させると、ある位置を境に騒音低減のメカニズムが劇的に変わることが分かったが、そのメカニズム解明については今後の課題である。, JAXA Research and Development Report, 宇宙航空研究開発機構研究開発報告

There are two potential uses of fly ash in asphalt mixtures: as a replacement of stone filler, or as a substitution for a certain percentage of bitumen. This paper focuses on the second option with the objective to investigate the interaction between fly ash and bitumen. Oscillatory tests were performed using a Dynamic Shear Rheometer (DSR) over a range of temperatures and frequencies, on original, short-term aged and longterm aged samples of fly ash-bitumen mastics. Additionally, testing using a Bending Beam Rheometer (BBR) was performed to assess resistance to low temperature cracking which is critical for modified bitumen with increased modulus. The addition of fly ash to bitumen improves the performance of the mastics and increases the viscosity and complex modulus at high temperatures and low frequencies, but has a negative effect on the resistance to cracking at low temperatures, thus increasing the low performance grade classification.

The objective of this study was to develop and evaluate an algorithm based on Fast Fourier Transform (FFT) that can calculate rational values of phase angle (f) and moduli of the variants of asphalt mixtures for the data obtained from the different frequency sweep tests. f and moduli for ten different asphalt mixtures resulting in over 690 data points collected from both USA and Sweden were computed using FFT. Theoretical observations revealed that there were significant differences for f between FFT and other methods to the order of 10-50%; however, there was no difference in moduli estimates for any mix and was independent of the test. Precisely, the FFT method produced rational f for mixtures that deviate from conventional mixture properties. Furthermore, statistical comparisons corroborated the predicted f estimates indicative of significant differences between the analysis techniques; but, the moduli were unaffected by the analysis methods. The study successfully illustrated the FFT technique, a user-friendly analytical procedure that can obviate the errors in the rational estimation of the acutely sensitive viscoelastic parameters., QC 20150202. QC 20200709

Based on Reissner plate theory, a novel model is proposed to analyze the buckling behavior of a circular or annular delaminated thin film on an elastic substrate. Elastic deformation in the substrate is calculated by using three coupled-line-springs distributed along the edge of the delaminated film. The shooting method is used to solve the nonlinear post-buckling problem. The energy release rate and phase angle are obtained. The results demonstrate that if the aspect ratio of delamination size to film thickness is not large enough, the Reissner plate theory should be used to have more accurate solutions. (C) 2010 Elsevier Ltd. All rights reserved.

Along the lines of Atkinson [3], a spectral theorem is proved for the boundary value problem, where f(t) is real-valued and P(t),B(t) are symmetric matrices, with B(t) positive definite. A suitable rotation index associated to the system is used to highlight the connections between the eigenvalues and the nodal properties of the corresponding eigenfunctions.

Based on Reissner plate theory, a novel model is proposed to analyze the buckling behavior of a circular or annular delaminated thin film on an elastic substrate. Elastic deformation in the substrate is calculated by using three coupled-line-springs distributed along the edge of the delaminated film. The shooting method is used to solve the nonlinear post-buckling problem. The energy release rate and phase angle are obtained. The results demonstrate that if the aspect ratio of delamination size to film thickness is not large enough, the Reissner plate theory should be used to have more accurate solutions. (C) 2010 Elsevier Ltd. All rights reserved.

Background: Malnutrition is highly prevalent among patients awaiting liver transplantation. Patients with poor nutritional status before transplant will have more complications and higher mortality postoperatively. Nutritional assessment should be performed in every patient with chronic liver disease awaiting liver transplantation in order to ensure correct and timely nutritional treatment, punctual monitoring pre- and post-transplant, and adequate global prognostic evaluation of the patient. Objective: The aim of the study was to identify a reliable and sensitive panel of measurements for the assessment of malnutrition in patients with chronic liver disease, which could also predict postoperative complications in orthotopic liver transplant recipients.Patients and methods: Twenty-five consecutive hospitalized ascitic patients (18 men, 7 women) with nonalcoholic liver cirrhosis were assessed with anthropometric measurements, handgrip strength and bioelectrical impedance analysis. Result: Comparison between the observed values (measured and calculated) in our 25 patients and the expected values based on percentile distribution showed statistically significant differences for the parameters triceps skinfold thickness, midarm circumference, arm muscle area, fat-free mass, handgrip strength and phase angle. Conclusion: The nutritional evaluation of cirrhotic patients awaiting liver transplant must be as exhaustive as possible. Bioelectrical impedance analysis adds a further parameter to anthropomet- ric measurements and handgrip strength, namely the phase angle, which provides usefulprognostic indications for the selection of candidates for liver transplantation.