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Composite nanobeams with carbon nanotube (CNT) reinforcement are crucial components in various applications due to their unique mechanical and thermal properties. The present work investigates the frequency–aspect ratio relationship in composite nanobeams with CNT reinforcement, particularly under varying temperatures, magnetic field strengths, and Winkler elastic stiffnesses. The non-dimensional frequency variation with aspect ratio, influenced by temperature differences, reveals distinct behavior patterns. The introduction of a magnetic field alters frequency characteristics, with uniform distribution (UD) nanobeams displaying higher frequencies. The impact of Winkler elastic stiffness, temperature differences, and magnetic field strengths on frequency elucidates differing responses between UD, X -type distribution (XD), and V -type distribution (VD) nanobeams. Nonlocal strain gradient theory proves essential in capturing dynamic characteristics influenced by CNT distribution. These findings shed light on the intricate dynamics of composite nanobeams, providing valuable insights for the design of future nano-devices employing CNT-reinforced composite beams as fundamental elements. [ABSTRACT FROM AUTHOR]

This manuscript proposes a hybrid method to predict the optimal nano‐metal matrix composites. The proposed hybrid technique is the wrapper of the Fire‐Hawk Optimizer (FHO) and Spiking Neural Network (SNN). Commonly it is known as FHO‐SNN method. The main objective of the proposed method is to improve the method parameters for better enhancement in mechanical properties. FHO approach is used to improve the process parameters of stirring squeeze casting method. The SNN predicts optimal parameters. Moreover, the problem based on the casting is reduced. By then the proposed hybrid technique performance is performed in the MATLAB platform and associated with various existing approaches. The proposed system shows the high tensile strength, impact energy and hardness compared with other existing methods. [ABSTRACT FROM AUTHOR]

Changes in subcutaneous adipose tissue (AT) structure and metabolism have been shown to correlate with the development of obesity and related metabolic disorders. Measurements of AT physiology could provide new insight into metabolic disease progression and response to therapy. An emerging functional imaging technology, diffuse optical spectroscopic imaging (DOSI), was used to obtain quantitative measures of near infrared (NIR) AT optical and physiological properties.Ten overweight or obese adults were assessed during 3 months on calorie-restricted diets. DOSI-derived tissue concentrations of hemoglobin, water and lipid and the wavelength-dependent scattering amplitude (A) and slope (b) obtained from 30 abdominal locations and three time points (T0, T6, T12) were calculated and analyzed using linear mixed-effects models and were also used to form 3D surface images.Subjects lost a mean of 11.7±3.4% of starting weight, while significant changes in A (+0.23±0.04 mm(-1), adj. P

Purpose: Time-resolved near-infrared spectroscopy was used to quantify tissue oxy- and deoxyhemoglobin concentrations ([HbO2] and [HbR]) and O2 saturation (stO2) in the oblique fibers of the vastus medialis muscle and brain prefrontal cortex during knee extension with and without blood flow restriction (BFR). Methods: Six young healthy males performed three sets of knee extensions on a dynamometer (50% one-repetition maximum) separated by 90-s rest periods in three conditions: 1) until fatigue without BFR (fatigue), 2) until fatigue with BFR (100 mm Hg cuff constriction around thigh (BFR)), 3) same number of repetitions from condition 2 without BFR (matched). Each condition was performed on a separate visit. Results: BFR was associated with higher [HbR] at the oblique fibers of the vastus medialis muscle (rest 1: 57.8 (BFR) vs 35.0 KM (matched); P < 0.0001) and a significantly lower stO2 during recovery periods between sets (7.5%-11.2 % lower than non-BFR conditions for rest 1 and 2, P < 0.0001). Using a piecewise linear spline method, a spike in [HbR] was observed before the onset of HbR clearance during recovery, causing HbR clearance to begin at a higher concentration (81 (BFR) vs 62 μM (matched), P = 0.029). [HbO2] kinetics during recovery were also affected by BFR, with longer duration (BFR, 51 s; matched, 31 s; P = 0.047) but lower rate of increase (BFR, 58 μM·min-1; matched, 89 μM·min-1; P = 0.004) during recovery. In the prefrontal cortex, BFR was associated with increased [HbR], diminished increase in [HbO2], and higher subjective exertion. Conclusions: These findings yield insight into possible physiological mechanisms of BFR and suggest a role of time-resolved near-infrared spectroscopy in monitoring and optimization of BFR exercise on an individual basis.

This research work reports the influence of 3-µm-sized Palm Sprout Shell Ash (PSSA) reinforcement on the mechanical and tribological behavior of the Al-Cu-Mg alloy. Composites of varying weight percentages of reinforcement ranging from 1 to 6 at intervals of 1 Wt.% were produced using the ultrasonic-assisted bottom-poured stir casting technique. Microstructural studies, mechanical testing, and wear properties analysis were performed on the alloy and the synthesized composites. The microstructure of the obtained samples was examined using Scanning Electron Microscope, Energy Dispersive Spectroscopy (SEM/EDS), and XRay Diffraction (XRD). The XRD patterns provided confirmation of the presence of PSSA (SiO2 and Al2O3) particles. The addition of PSSA reinforcement has significantly improved the hardness, tensile strength, and compression strength of composites. The hardness, ultimate tensile strength, and compression strength were improved by 13.89%, 24.04%, and 32.93%, respectively, with the 6 Wt.% PSSA-reinforced composite. However, the incorporation of reinforcement has resulted in a decrease in the ductility of the Al-Cu-Mg alloy composite; the maximum decrement of 42.87% was with the 6% PSSA-reinforced composite. Tests were conducted at different loads and speeds to evaluate the wear behavior of the prepared samples. Superior wear resistance was observed in the composites. The fracture and wear mechanisms of reinforced and unreinforced were observed using SEM. [ABSTRACT FROM AUTHOR]

Abstract Context In India, hip fracture crude incidence above the age of 50 years was 129 per 100,000. Aims The aim of this study is to analyze the in-hospital mortality following proximal femur fractures in elderly Indian population. Methods and Material The study was done in Sri Ramachandra Medical Center, Chennai, India. Patient's records were retrospectively evaluated for a period of 3 years from January 1, 2015 to January 1, 2018. The inclusion criteria were patients both male and female aged more than 65 years admitted with the diagnosis of neck of femur or intertrochanteric or subtrochanteric fractures. The exclusion criteria were patients having any associated fracture or previous hip fracture history or diagnosed primary or secondary malignancies. To evaluate any surgical delay two groups were formed. After eliminating cases based on exclusion criteria, we had 270 patients for evaluation. Statistical Analysis Used The collected data were analyzed with IBM.SPSS statistics software 23.0 Version. To describe about the data descriptive statistics frequency analysis, percentage analysis were used for categorical variables and the mean and standard deviation (SD) were used for continuous variables. To find the significant difference between the bivariate samples, Student's t-test and analysis of variance (ANOVA) were used. The p-value of 0.05 is considered as significant level. Results We had a total of 24 mortalities with 15 males and 9 females. The in-hospital mortality of patients who underwent replacement surgeries for proximal femur fractures was 14 in our study. Sixteen of the in-hospital mortality patients had low Parker's mobility score. Twenty patients had mortality when surgery was delayed more than 48 hours. Conclusions In-hospital mortality in elderly patients having proximal femur fracture increases significantly if the patient was having low-preoperative mobility status, if surgery was delayed more than 48 hours, and if patient undergoes replacement surgeries.

Vitamin A deficiency is a major world health problem, affecting up to 127 million pre-school children and 7 millionpregnant women worldwide (West, 2003). Human selection for yellow endosperm has led to diversification of graincarotenoid content and composition. This variation has remained largely untapped in modern breeding programs thathave focused nearly exclusively on yield gains. Maize displays considerable natural variation for carotenoidcomposition, including vitamin A precursors α-carotene, β-carotene, and β -cryptoxanthin. Sixty four maize inbred linesof India were grown and evaluated for whole kernel carotenoids and beta carotene content using high performanceliquid chromatography (HPLC). The lines averaged 14 :g/g for total carotenoids (5.58 to 63.9 :g/g) and 1.69 :g/g for β-carotene (0.122 to 4.74 :g/g). High level of β - carotene was observed in UMI 946, UMI 176, UMI 79, UMI 34 andUMI 12 and these would be used in the breeding programs to enhance the β – carotene contents. Previous study showedfour natural lcyE polymorphisms explained 58% of the variation in these two branches and a threefold difference in provitaminA compounds. In screening for polymorphisms in key haplotypes, four regions were selected and scored acrossthe entire panel of favourable haplotype using SNP and SSR markers. The polymorphs were obtained for all primer usedand the presence of the amplification of for particular marker showed the increase in β - carotene content across theinbreds. Development of LCYE based breeding markers for maize alone will not be effective unless hydroxylation isalso controlled, for non pro vitamin A xanthophylls compounds will predominate. So in our future study, we should beaiming at breeding for high β - carotene in maize by emphasizing on characterization of β - carotene hydroxylase genesfor enhancing the relative levels of seed β - carotene.