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Conservation practices are encouraged to improve soil health and sustain agronomic crop production. Mehlich-3 is often used as a multi-nutrient extractant to determine soil fertility status. A study investigated the impacts of the conservation practices of gypsum, cover crops, and crop rotation on 28 Mehlich-3 extractable elements, of which 11 were considered plant nutrients, from soil at three midwestern US locations. Soil was collected from 0 to 15 and 15–30 cm depths 5 years after implementing the conservation practices. Treatments consisted of (1) with and without cereal rye (Secale cereale L.) winter cover, (2) continuous soybean [Glycine max (L.) Merr.] vs. soybean-corn (Zea mays L.) rotation, and (3) annual gypsum application (0, 1.1, and 2.2 Mg ha−1). Differences were observed by site, depth, and conservation practice depending on the element evaluated. Minimal interactive effects were observed among treatments. The most consistent effect was observed for crop rotation across sites. Gypsum only affected the site with the greatest clay content, where more Ca and S were retained, and Mg and Mn displaced. Cover crop only affected elements at this high clay site, where different elements were positively or negatively affected. Results suggest that not one practice fits all, and optimum conservation practices must be tailored for the site.

In this comprehensive review, we dive into the potential of natural fibre composites, tracing their historical use spanning three millennia and their recent incorporation into polymer matrices. Various natural fibres, including flax, hemp, jute, and more, have been explored as potential reinforcements due to their renewable nature and environmental appeal. Moreover, these fibers are gaining traction in industries such as automotive and packaging. Leveraging abundant agricultural waste such as, wheat husk, rice husk, straw, and hemp fibre into commercially viable fibre-reinforced polymer composites. A thorough summary is given in this article of the diverse array of natural fibers, their current research status, encompassing properties, processing techniques, filler materials on structural factors, thermogravimetric analysis, dynamic mechanical performance under thermal loading, fire retardant behaviour, cone calorimetric analysis and various other applications, all while referencing the latest developments in the field, exploring a sustainable future with natural fibre composites. Furthermore, the difficulties associated with natural fibre-reinforced composites, including their vulnerability to humidity, fire retardancy and compliance with fibre matrices, are examined. This paper summarizes the complex field of natural fibre composites and covers several thermal stability-related appearance.

The present study investigates the influence of hybrid interleaving technique using Glass and Carbon veils to improve the mode-I fracture toughness in Glass epoxy laminates. Commercially available non-woven Carbon and Glass veils with different areal densities were used to develop hybrid interleaved composites. Two approaches of interleaving, namely inter-ply and inter-weaved veils, were followed to manufacture the interleaved composite laminates using the hand layup technique. Double Cantilever Beam (DCB) samples were tested to estimate the interlaminar fracture toughness (IFT). Test results indicate that the inter-ply interleaved composite (I-C30G30) exhibited an improved initial and propagation fracture toughness of about 16.98% and 3.08%, respectively. A decreased IFT during initiation and propagation was observed for I-C15G30 and I-C20G30 when compared to plain samples. In case of inter-weaved veil interleaving approach, an improved fracture toughness (GIC and GIP) of about 7.96% and 12.94%, respectively, was observed for W-C15G30 sample, nevertheless W-C20G30 and W-C30G30 showed a drop in fracture toughness (GIC) of an about 12.15% and 9.22%, respectively, and an improvement in fracture toughness (GIP) of about 12.37% and 13.82%, respectively, when compared to plain sample. Scanning electron photo images (SEPI) of cracked laminates witnessed the fracture mechanisms involved in hybrid ply interleaved and non-interleaved composite laminates

Damage detection in composite materials is crucial for ensuring the safety and reliability of engineering structures. Conventional methods often face challenges in accurately identifying damage in plate-like structures, particularly in scenarios involving multiple damages or small-scale delamination. This study focuses on investigating the detection and localization of delamination in composite plates by employing both experimental and numerical modal analysis. An eight-ply woven Glass-Epoxy composite laminate with and without damage was prepared with the aid of hand lamination technique. Laminate was fixed to a Clamped-Free-Free-Free (CFFF) boundary condition for experimental modal analysis by introducing controlled damage to examine its impact on modal properties. To validate the natural frequencies (NFs) of damaged and undamaged composite laminates, a numerical analysis was conducted using ANSYS Parametric Design Language (APDL). Further, to advance the understanding of using modal shapes and their spatial derivatives for damage localization in composite plates under various damage situations, post-processing of simulation results was conducted using MATLAB. Finite Difference Method has been employed to calculate the derivatives, and a novel damage index (DI) is proposed to enhance damage localization capabilities. The results affirm that the proposed DI is effective and precise in identifying damage in plate-like structures, both for individual and multiple damage scenarios. This research study presents a novel approach for identifying and pinpointing damage in composite plates, thereby making a valuable contribution to the field of structural health monitoring (SHM) applications

Background and Aims: The prone position is one of the common surgical positions used in clinical practice. Manoeuvring patients from supine to a prone position can impact respiratory dynamics and result in haemodynamic variations. Methods: This study included 64 patients and was conducted after obtaining approval from the ethics committee and registration of the trial. The primary objective was to evaluate the changes in peak inspiratory pressure (PIP), plateau pressure (P[sub.plat]) and mean airway pressure (MAP) in patients undergoing surgery under general anaesthesia in the prone position with (Group S) and without (Group P) spine frame. The secondary objective was to evaluate and compare the variations in heart rate and blood pressure. Results: On turning the patient prone, there was statistically significant increase in median PIP (Group S 4 cmH[sub.2]O vs. Group P 0.5 cmH[sub.2]O, P < 0.001), P[sub.plat] (Group S 3.5 cmH[sub.2]O vs. Group P 1 cmH[sub.2]O, P = 0.004) and dynamic compliance (Group S -5.513 vs. Group P -2.78, P < 0.004). Conclusions: Our study found that prone positioning with a spine frame led to a significantly greater increase in airway pressures and a decrease in dynamic compliance when compared to patients positioned prone without the spine frame. Keywords: Lung compliance, nephrolithotomy, patient positioning, prone position, respiratory dynamics, spine surgery, spine frame, Author(s): Preeti Kandasamy [1]; Vinayak S. Pujari (corresponding author) [2]; Sandya Rani D. Channaiah [1] INTRODUCTION Prone positioning is one of the common positions used to facilitate surgical access, but [...]

Fiber-reinforced polymer (FRP) is a composite material made of a polymer matrix reinforced with fibers. Hybrid composites are referred to as high-performance FRP materials used in safety-critical structural applications. Generally, FRP composite laminates are very weak in their out-of-plane properties, to address this issue unidirectional (UD) Glass laminates are prepared by modifying the matrix using plasma-treated multi-walled carbon nanotubes (MWCNTs) in epoxy matrix and compared fracture toughness characteristics with low-cost micro fillers like Aluminum oxide (Al2O3) and Sodium Carbonate (Na2CO3). These Nano and Micro fillers are loaded with 0.5wt%, 1wt% and 2wt% in the epoxy matrix while making FRP laminates. Adding these fillers into the epoxy matrix was caused a significant increase in the out-of-plane load-bearing capacity of the composites as compared to plain Glass epoxy laminates. Thus, the fracture toughness was enhanced by 20-26% and 14-17% under mode I and mode II loading respectively. Further, a Scanning electron microscopic analysis was also done on delaminated glass laminates to understand the failure mechanisms

Advanced polymer matrix composites are gaining the market in their way due to their exceptional specific stiffness, specific strength, fatigue, and corrosion resistance in the field of Auto-Tech, Aero-Tech, Biotech, etc. However, the lack of ductility and catastrophic failure has limited their application in these areas. Hence there is a need to explore the state of art technological developments in designing toughened composites by minimizing their factor of safety. A new generation of high-performance composites with pseudo-ductile or ductile behavior is essentially required for the fiber-reinforced composite structures to mitigate the catastrophic failures. The present High-Performance Ductile Composite Technology (HiPerDuCT) program is jointly between the University of Bristol U.K and Imperial College London working to address this challenge by developing newer materials. The various fiber architectures made under this project gave a more gradual failure rather than catastrophic failure with improved mechanical properties. This review mainly focuses on summarizing the pseudo ductility evolution in fiber-reinforced composites by eminent researchers with a possible alternative like fiber positions in matrix materials for introducing reasonable ductility in composites.

Background: A vast literature investigated the role of vitamins in wound healing and pain control. In our study, we explored the role of vitamin C supplementation for various parameters, post periodontal flap surgery in patients with chronic generalized periodontitis. Objectives: (1) to assess and record the Laundry wound healing index and visual analog scale (VAS) score at 3-, 7-, 14-, and 30-day postoperative. (2) To determine the gingival healing and oral hygiene status using PI Loe and Silness 1964 (PI), Lobene Gingival Index 1986 (GI). (3) To determine and compare the pocket depth (PD) and clinical attachment level (CAL) with and without supplementation at 3- and 6-week postoperative. Methods: A randomized triple-blind study was conducted on 60 patients half receiving vitamin C supplementation. The VAS score, wound healing index, PI, GI, PD, and CAL were determined and compared at different time intervals. Results: Statistical analysis was done for the recorded data. Chi-square test for the healing index and Friedmann’s test followed by Wilcoxon signed-rank test for VAS showed statistically significant results (P < 0.05). Friedmann’s test found a statistically significant (P < 0.05) result for the PI score only in the test group. Friedmann’s test found the PI to be statistically significant in the test group (P < 0.05). Friedmann’s test followed by Wilcoxon signed-rank test found the PD and CAL to be statistically significant (P < 0.05) at all different time intervals. Conclusion: In the study, vitamin C supplementation enhanced wound healing and lessened postoperative pain. An instant benefit of vitamin C supplementation was found in this study. A prolonged supplementation and further studies with a considerable sample size would justify the use of vitamin supplementation.