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The present study investigates the mode‐II fracture resistance and interlaminar shear strength (ILSS) in glass epoxy laminates with the aid of glass‐carbon veils hybrid interleaving technique. Hybrid interleaves were prepared using various areal densities of non‐woven carbon and glass veils. Two methods, specifically inter‐ply and inter‐weaved ply interleaved glass epoxy composite laminates were manufactured by hand layup technique. End notch flexural and short beam test specimens were tested to estimate the mode‐II fracture resistance and ILSS. Test results indicated that the interleaved with inter‐weaved veil composite exhibited ~58% to ~82% and ~13% to ~61% enhancement for inter‐ply veil composite laminates when compared to plain samples. In context with the short beam test, a significant enhancement of approximately 23% in ILSS was noticed for the plain inter‐weaved veil constructed with a lower areal density of the carbon veil. Finally, the plain inter‐weaved interleaving technique has a prominent role in enhancing the resistance to fracture and shear strength in Glass epoxy laminates. Further, the fracture mechanisms of non‐interleaved and hybrid ply interleaved composite laminates were observed by scanning electron microscopic images. Highlights: Interleaving non‐woven microfiber veil is the most promising and cost‐effective strategy to enhance the Interlayer toughness and strength.Interleaving techniques used in this investigation have a significant effect on interlaminar fracture toughness (IFT) and interlaminar shear strength (ILSS).The areal density of high‐modulus carbon veil showed a different phenomenal influence on IFT and ILSS. [ABSTRACT FROM AUTHOR]

The prevalence of cardiovascular diseases (CVDs) has significantly increased in recent years due to changes in lifestyle, dietary habits, and environmental factors. Irudhaya noi, the encompassing term for cardiovascular diseases in Siddha, has witnessed a surge in prevalence. Cardiovascular diseases (CVDs) comprise several conditions affecting the heart and blood vessels, such as coronary heart disease, heart attacks, stroke, hypertension, peripheral artery disease, rheumatic heart disease, congenital heart disease, and heart failure. Siddha identifies imbalances in the three doshas as the main cause of heart-related ailments, and restoring their balance presents a challenging challenge in the treatment of cardiovascular diseases. Herbal treatments have been essential in human healthcare throughout history, as various traditional medical systems have used them to treat a wide range of maladies. Siddha is an ancient and internationally renowned traditional method of medicine. This review study examines the crucial role of Siddha in the prevention, management, and evaluation of cardiovascular diseases (CVDs) using interventions linked to diet (Unavu), lifestyle, seasonal routines (Kaala ozukkam), yoga, everyday routines (Naal ozukkam), and rejuvenation therapies (Kaaya kalpam). The research elucidates how Siddha's comprehensive methodology tackles the underlying factors of cardiovascular diseases (CVDs), providing significant perspectives on preventive measures, lifestyle adjustments, and herbal treatments. This review seeks to offer a complete viewpoint on the potential of Siddha in addressing the increasing prevalence of cardiovascular problems in modern society by combining traditional wisdom with contemporary scientific understanding. [ABSTRACT FROM AUTHOR]

Background and Aims: Spinal anesthesia is a safe and reliable technique for surgeries on the lower abdomen and lower limbs. Some of its characteristics like delayed ambulation and pain after block regression may limit its use, especially for short duration surgeries. 2-chloroprocaine is an amino-ester local anesthetic with an approximate duration of action of 40 minutes, which is ideal for short duration surgeries. This study aims to compare the effect of adding intrathecal buprenorphine to 2-chloroprocaine with regard to spinal anesthesia characteristics. Material and Methods: After obtaining the institutional ethical committee clearance and clinical trial registration, informed consent was taken from 90 patients who were undergoing either lower abdominal or lower limb surgeries of less than 60 minutes duration and were then randomized into two groups. Group C received 40 mg of 1% 2-chloroprocaine and Group B received 40 mg of 1% 2-chloroprocaine with 60 mcg of buprenorphine. Sensory/motor block characteristics, first analgesic requirements, time to void, and unassisted ambulation were assessed. Student t test was used to analyze the metric parameters and Fisher's exact test was used to compare the categorical variables. Results: The time of onset of sensory and motor blocks, peak sensory block, readiness for surgery, and complete regression of both sensory and motor blocks were comparable between the groups. Group B showed significantly prolonged duration of postoperative analgesia (855.82 ± 667.09 vs. 359.07 ± 253.3 minutes). 91.1% patients were able to ambulate within 100 minutes in our study. Conclusion: We conclude that addition of buprenorphine to 2-chloroprocaine has a significant synergistic effect on prolonging postoperative analgesia.

Hydrogen sulfide (H2S) exhibits protective effects in cardiovascular disease such as myocardial ischemia/reperfusion (I/R) injury, cardiac hypertrophy, and atherosclerosis. Despite these findings, its mechanism of action remains elusive. Recent studies suggest that H2S can modulate protein activity through redox-based post-translational modifications of protein cysteine residues forming hydropersulfides (RSSH). Furthermore, emerging evidence indicates that reactive sulfur species, including RSSH and polysulfides, exhibit cardioprotective action. However, it is not clear yet whether there are any pharmacological differences in the use of H2S vs. RSSH and/or polysulfides. This study aims to examine the differing cardioprotective effects of distinct reactive sulfur species (RSS) such as H2S, RSSH, and dialkyl trisulfides (RSSSR) compared with canonical ischemic post-conditioning in the context of a Langendorff ex-vivo myocardial I/R injury model. For the first time, a side-by-side study has revealed that exogenous RSSH donation is a superior approach to maintain post-ischemic function and limit infarct size when compared with other RSS and mechanical post-conditioning. Our results also suggest that RSSH preserves mitochondrial respiration in H9c2 cardiomyocytes exposed to hypoxia-reoxygenation via inhibition of oxidative phosphorylation while preserving cell viability.

Dynamics of wireless communication, resource constraints, and application diversity pose significant challenges to data transport control in wireless sensor networks. In this chapter, we examine the issue of data transport control in the context of two typical communication patterns in wireless sensor networks: convergecast and broadcast. We study the similarity and differences of data transport control in convergecast and broadcast, we discuss existing convergecast and broadcast protocols, and we present open issues for data transport control in wireless sensor networks.

We have examined seismic data and wireless network characteristics from 100 broadband stations installed from Acapulco to Tampico in Mexico over a period of 1.5 years (2005-2007). The instruments were part of the MASE (Middle America Subduction Experiment) which has the objective to build a geodynamical model of the subduction process beneath the Middle America Trench. The stations had a 5-6 km spacing and were connected wirelessly with each other providing a unique data set. It allows examination of various aspects in tomography, shear wave splitting, wave travel times as well as extensive analysis of the wireless network used for data delivery. Tomographic and SKS splitting studies in this area show the presence of a 50-80 km thick flat slab under the western part of the array, and a steeply dipping slab beneath its center to a depth of ~550km and ~375 km inland.The research in wireless area displays no correlation between SNR and throughput and a rough correlation between the throughput and the distance for the majority of the links. Various network tuning techniques were applied to further investigate the properties of the communication hardware and data transmission. A new disruption tolerant shell (DTS) was tested that provides duplex communication with the network and handles breaks in the RF communication by temporarily storing data and transmitting when a conection has been restored.

Most sensor network research and software design has been guided by an architectural principle that permits multi-node data fusion on small-form-factor, resource-poor nodes, or motes. We argue that this principle leads to fragile and unmanageable systems and explore an alternative. The Tenet architecture is motivated by the observation that future large-scale sensor network deployments will be tiered, consisting of motes in the lower tier and masters, relatively unconstrained 32-bit platform nodes, in the upper tier. Masters provide increased network capacity. Tenet constrains multinode fusion to the master tier while allowing motes to process locally-generated sensor data. This simplifies application development and allows mote-tier software to be reused. Applications running on masters task motes by composing task descriptions from a novel tasking library. We have demonstrated Tenet's effectiveness by implementing and deploying three applications. Our ambient vibration monitoring application collected 3-channel acceleration data at 20 Hz over a 570 ft span of a suspension bridge for 24 hours. In the Pursuit-evasion game, a Pioneer robot used a 56-node sensor network deployed in a hallway of a building to quickly and accurately estimate the location of an evader and successfully captured the mobile evader. In a wildlife counting application, Cyclops nodes used local image processing techniques, configured and expressed as Tenet tasks, to detect the presence of animals and stream the images to a database.

CENS research related to developing and implementing structural health monitoring (SHM) systems is advancing on two distinct but related fronts; ShakeNet, a portable wireless sensor network for instrumenting civil structures and SHMnet, for monitoring of tall buildings in Los Angeles. SHM is the process of assessing the state of health (e.g., damage) of instrumented structures from measurements. The goal of SHM is to improve safety and reliability of infrastructure systems by detecting damage before it reaches a critical state, or to allow rapid post-event assessment. The primary objective of the SHMnet research is the development of a robust SHM system along with the associated hardware and software, using tall and special buildings in Los Angeles as a testbed. To manage this large-scale, multi-disciplinary goal, the work tasks are divided into several key focus areas, each with specific objectives, including the development of; a robust wireless Data Acquisition (DAQ) toolbox suitable for rapid urban deployments, a suite of state-of-the-art sensors for monitoring key structural responses including an innovative laser/photodiode for directly measuring interstory drift, and probabilistic post-event assessment algorithms based on experimental motion-damage relationships. A confluence of events, namely the local boom in tall building design and construction, the LA-DBS instrumentation requirements for tall buildings, the technology and experience of CENS and nees@UCLA, coupled with the active participation of key industrial partners, provides the synergy required to enable the proposed research.ShakeNet is a vibration sensor network designed for use in civil structures such as buildings and bridges for system identification and for identifying potential locations of damage due to earthquake motions. ShakeNet can also be used in test structures loaded to failure to characterize damage signals in waveform data such as those produced by moment-frame weld fractures. ShakeNet is a multi-tier wireless sensing system of 75 wireless nodes that can be rapidly deployed by 2-3 people on, for example, multiple floors of a large building. It will be designed to collect structural vibration measurements for up to a week from each node within the network. This portable system can be used to instrument large structures within hours immediately after an earthquake. Significant aftershocks of even moderate-size earthquakes occur for up to a week after the earthquake. What makes ShakeNet application-realistic is careful attention to the design of its data-acquisition hardware, the ShakeBoard. The ShakeBoard is a 24-bit high resolution acceleration data acquisition system that uses commercial low-noise MEMS accelerometers and conforms to specifications currently being established by the US Geological Survey for their Advanced National Seismic System (ANSS). ShakeNet’s software subsystem will be built upon Tenet; programmable wireless sensing software designed for multi-tier sensor networks. The strength of ShakeNet lies in the planned field tests in order to make it application-realistic. Future tests of ShakeNet, pending project funding, include deployments in moment-frame steel and reinforced concrete buildings, a bridge, and a dam near the San Andreas Fault.

The thermal variation and conductive–convective heat transfer aspects of the moving annular fin have been analyzed in the existence of internal heat generation. In addition, the behavior of radial and tangential stress of an annular moving fin is probed in this study. Appropriate dimensionless terms are used to convert the governing nonlinear temperature equation to a nonlinear ordinary differential equation (ODE), and then a series solution is obtained using the least square method (LSM). Furthermore, the impact of thermal dimensionless parameters including Peclet number and heat generation number on temperature, radial and tangential distributions is investigated comprehensively. The outcomes of assessing the effects of these parameter variations on temperature and stress profiles are expressed graphically and in tabular format. The analysis of thermal stress and dispersal in the fin reveals an improvement as the Peclet number and heat generation accumulate. Meanwhile, elevated convective parameter values result in reduced thermal distribution. [ABSTRACT FROM AUTHOR]

This document is a list of references for research articles related to the topic of interlaminar fracture toughness in composite materials. The articles cover various aspects of the subject, including the use of different materials and techniques to enhance fracture toughness, such as surface treatments, coatings, veils, and nanofibers. The articles also explore the effects of different factors, such as fiber type and length, on interlaminar fracture toughness. [Extracted from the article]

The discordance between genome size and the complexity of eukaryotes can partly be attributed to differences in repeat density. The Muller F element (∼5.2 Mb) is the smallest chromosome in Drosophila melanogaster, but it is substantially larger (>18.7 Mb) in D. ananassae. To identify the major contributors to the expansion of the F element and to assess their impact, we improved the genome sequence and annotated the genes in a 1.4-Mb region of the D. ananassae F element, and a 1.7-Mb region from the D element for comparison. We find that transposons (particularly LTR and LINE retrotransposons) are major contributors to this expansion (78.6%), while Wolbachia sequences integrated into the D. ananassae genome are minor contributors (0.02%). Both D. melanogaster and D. ananassae F-element genes exhibit distinct characteristics compared to D-element genes (e.g., larger coding spans, larger introns, more coding exons, and lower codon bias), but these differences are exaggerated in D. ananassae. Compared to D. melanogaster, the codon bias observed in D. ananassae F-element genes can primarily be attributed to mutational biases instead of selection. The 5′ ends of F-element genes in both species are enriched in dimethylation of lysine 4 on histone 3 (H3K4me2), while the coding spans are enriched in H3K9me2. Despite differences in repeat density and gene characteristics, D. ananassae F-element genes show a similar range of expression levels compared to genes in euchromatic domains. This study improves our understanding of how transposons can affect genome size and how genes can function within highly repetitive domains.

Abstract Growing demand for soybean [Glycine max (L.) Merr.] creates pressure to expand soybean production onto marginal lands and grow soybean continuously. Experiments comparing continuous soybean with soybean–corn (Zea mays L.) rotation, cereal rye [Secale cereale (L.)] cover crop with no cover crop, and flue‐gas desulfurization (FGD) gypsum surface‐applied at 0, 1.1, and 2.2 Mg ha−1 were conducted at Shorter, AL, Farmland, IN, Hoytville, OH, and Piketon, OH, for 5 yr. The objective was to evaluate soybean yield response to these practices across a range of soil types and climatic conditions. Response to continuous soybean and cover crop varied by site (soil drainage class) with no interaction effects. Continuous soybean reduced yield only on well‐ and moderately well‐drained soil types. Cover crop reduced yield on the very poorly drained soil type and increased yield on the well‐drained soil type. Crop production practices that promote soil health and sustainability may not provide yield improvement.