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Liquefaction can cause significant damage to the built environment; therefore, assessing the liquefaction hazard in a seismically active region is essential to minimize the risk. This study attempted to evaluate the liquefaction potential of the south-central coastal areas of Bangladesh by calculating the liquefaction potential index (LPI) considering a scenario earthquake of Mw ​= ​7.5 having a peak ground acceleration of 0.15g. For calculating LPI, both standard penetration test blow count (SPT-N) and shear wave velocity (Vs) data have been used in this study. The results show that the study area's LPI values vary from 0 to 37. A liquefaction hazard map is prepared for the area using the calculated LPI values from Vsdata shows about 8% of the study area is very highly susceptible to liquefaction hazard, whereas 62% of the area falls under high hazard-prone area while about 28% and 2% area of the study have respectively low (0

The thermal, physical, and mechanical properties of ecologically sustainable composite materials made of sponge gourd outer skin fiber and vinyl ester matrix are examined in this study. Vinyl ester was compression molded using sponge gourd outer skin fiber, a novel reinforcing material. Sponge gourd outer skin fiber was prepared using chemical, sun-drying, and furnace-drying methods. At different fiber loadings (0, 10, 15, 20, and 30 wt.%), the study examined mechanical (tensile, flexural, impact, hardness), physical (water absorption, biodegradability), thermal, chemical, and matrix-fiber bonding properties. The composite material with 30% fiber loading has better mechanical characteristics over 0 wt.% such as 2.1 times in tensile strength, 2.2 times in flexural strength, and 4.5 times in impact strength as compared to the pure vinyl ester material, greatest average hardness value of 96 on the Shore A scale. FTIR and TGA were used to study chemical distribution and thermal stability. The study found that 30% fiber loading improved tensile, flexural, impact, and hardness. The material’s biodegradability studies showed its environmental friendliness. The results support sustainable composites in aircraft, automotive, and construction. As a link between surface shape and stress-strain distribution, the fiber-matrix interface affects material characteristics. By reducing dependency on non-renewable resources, natural fibers in composite materials increase performance and environmental sustainability.

The depletion of fossil fuels and increasing demand for the sustainable energy storage have driven research toward agricultural biomass-based activated carbons as a promising alternative for supercapacitor electrodes. This review explores the perspective of biomass-based activated carbons, highlighting their advantages, such as renewability, low cost, and abundant availability. It also discusses the conversion process of agricultural waste into activated carbons, emphasizing the role of activation methods in tailoring the pore structure and surface chemistry for enhanced electrochemical performance. The key characteristics of activated carbons derived from various agricultural sources and their effects on the specific capacitance and energy/power density are compared and analyzed. Furthermore, this review has addressed the challenges of using agricultural biomass for activated carbon production, including process optimization and environmental considerations. Finally, this review summarizes the future outlook of this field, and current research efforts to develop high-performance, sustainable supercapacitors using agricultural biomass-derived activated carbons.

Bamboo fiber has attracted a lot of interest due to its high specific strength and renewability. Unidirectional long bamboo fiber reinforcing is essential to fully realize its strength. The reinforcing efficiency can also be affected by the physical and chemical structure of bamboo fibers. Therefore, this study reviews the cell wall structure of the bamboo fiber. The alternately arranged structure with thin and thick layers contributes substantially to the mechanical strength of the bamboo fiber. In addition, this study evaluates the mechanical properties, water absorption, and flame retardancy of polymeric and cementitious composites reinforced with long bamboo fibers. Thermoset polymer-based bamboo fiber composites typically show higher mechanical strength than thermoplastic-based fiber composites. Chemical treatment and flame retardant can significantly enhance the hydrophobicity and flame retardancy of fiber composites, respectively. Because of its superior interface performance, the short bamboo fiber has a greater reinforcing effect in cement mortar than in concrete. This study can serve as a reference for further investigations on bamboo fiber/bundle reinforced composites and promote their applications.

Water deficit is a major abiotic stress that devastatingly affects wheat growth and production, particularly in arid environments. Moreover, drought is expected to become more frequent and severe owing to current climate change. Consequently, it is necessary to find affordable approaches to enhance drought tolerance, principally for important crops such as wheat. The present study is a controlled pot experiment which was performed to investigate the efficiency of soil application or exogenous foliar of zinc sulfate (ZnSO4·7H2O) or/and iron sulfate (FeSO4·7H2O) to attenuate the deleterious impacts of drought stress in winter wheat. The plants were exposed to water deficit (40% field capacity) versus well-watered conditions (80% field capacity). Drought stress significantly declined relative water content and leaf chlorophyll content while increased proline accumulation, water saturation deficit, and water uptake capacity relative to well-watered conditions. Moreover, leaf characters (number and area) significantly diminished as a result of water deficit. The detrimental impacts on physiological and morphological attributes reflected a considerable reduction in grain yield and all contributed traits. However, the soil- and foliar-applied zinc sulfate or/and iron sulfate significantly enhanced all aforementioned depressed parameters which reflected markedly in enhancing yield traits under drought stress. Among the investigated treatments, the exogenous foliar applications were more effective in promoting drought tolerance particularly combined both micronutrients which can be employed in reducing the losses caused by drought stress in wheat-growing regions.

Abstract: This study investigated the restorative effect of Leea macrophyllaethanol root extract (LMERE) in carbon tetrachloride (CCl4) induced hepatic injury. It also tried to unfold the underlying mechanism through ligand-receptor interactions. Prior to conduct the CCl4induced animal model study, the in vitro antioxidative capacities of LMERE were investigated. Gas chromatography mass spectroscopy (GC–MS) was accomplished to identify the prevalent bioactive compounds. The molecular docking was performed using Schrödinger Suites 2017-1. Results showed the promising antioxidative potentials of LMERE in in vitro models. Upon treatment of CCl4intoxicated animals with LMERE, serum ALT and AST were found to be significantly (p< 0.05) reduced compared to the CCl4control while LMERE50 was noted as the best dose in restoring the hepatic markers. Serum lipids and total protein were significantly restored compared to control. Remarkable changes of cell necrosis, apoptosis and sinusoidal dilution were noticed in histopathological assay of liver tissue. mRNA expression for superoxide dismutase (SOD1) and catalase was multifold increased which are statistically significant compared to reference drug, silymarin. In docking study, octadecanoic acid showed the lowest binding energy and highest binding affinity with the protein (ID: 1VKX) which is a crystallized structure of NF-κB p50/p65 heterodimer involved in cytokine production. The findings demonstrate that LMERE restores the hepatic damage by the mRNA expression of antioxidative enzymes while LMERE50, at a glance, seems the most suitable dose. Graphic abstract:

This research examines how the shear properties of glass fiber-reinforced polymer (GFRP) and steel single-lap joints react under various temperatures (−25, 0, 25, 50, and 100℃) and loading speeds (0.625, 1.25, 2.5, and 5.0m/s). The GFRP sheets, aligned unidirectionally, were produced using vacuum-assisted resin transfer molding (VARTM) and were then adhesively attached to steel plates with an epoxy resin. The assemblies were subjected to a high-speed servo-hydraulic testing apparatus for evaluation. The results indicate that the joint's performance is relatively unaffected by changes in the loading speed, but the overall toughness tends to decrease at higher speeds. However, the adhesive bond strength increases when temperatures are between −25 to 50℃ but diminishes as temperatures rise from 50 to 100℃. The majority of the samples exhibited debonding at the steel-adhesive interface under varied speeds and colder temperatures, whereas debonding at the GFRP-adhesive interface was more prevalent at elevated temperatures. These insights are vital for both theoretical analyses and practical implementations of GFRP-steel single-lap joints in environments subject to extreme loading conditions and temperatures.

Studies investigating the challenges and barriers faced by ethnic minority entrepreneurs have often concentrated on areas where there is a large supportive ethnic minority community. Less work has been conducted on the experience of those entrepreneurs operating in cities where such ethnic resources may be less widely available. Considered from the perspective of mixed embeddedness framework, this study uses face-to-face interviews with 25 ethnic minority entrepreneurs to gain a greater understanding of the constraints experienced by the starting and running businesses in one such location, the Scottish city of Aberdeen in the United Kingdom. Although issues found by previous studies such as access to funding remain an issue, the entrepreneurs indicated problems with access to labour as United Kingdom Border Agency’s immigration rules and tightening of the Post Study Work visa have had a profound effect on these entrepreneurs. The results imply that the weakening of the ethnic resource microsphere has not opened up opportunities which are exploited by the entrepreneurs, but they have still been exposed to external forces from the regulatory macrosphere. Both entrepreneurs and policymakers need to think carefully about the retention, training and recruitment of staff. In particular, the wider ramifications of immigration rule changes need to be considered, but also whether entrepreneurs need to be more open to the potential of recruiting non-ethnic employees and if so what support is required to achieve this.

Several polymer-based nanocomposites have been studied and used for tissue engineering applications in recent years. These biodegradable nanocomposites have proven advantageous for bone tissue cultivation and production. Materials such as polymers, metals, and ceramics are commonly used to fabricate biomaterials. Although some polymeric materials are biodegradable and bioactive in bone tissue engineering applications, they do not match the strength of the bone. On the other hand, metals come in various shapes and sizes, including screws, pins, plates, and stents. These metallic implants are mechanically strong and can temporarily support bones, joints, and teeth. They are neither absorbed/resorbed by the body nor transformed into bone. With metal implants, there is also a possibility of infection and secondary operations. In contrast, polymer nanocomposites have bioinertness, low chemical reactivity, biocompatibility, osseointegration, regeneration, and deposition of mineral components capability. They can mimic bones, joints, and teeth in orthopedic applications to repair and replace damaged or diseased tissues. This study reviews current research on bone regeneration technology and potential treatment options for bone tissue regeneration in specific bone abnormalities with nanocomposites. The incorporation of growth factors into nanocomposite scaffolds for osteogenesis and bone remodeling is also discussed.

•Total analysis of heavy metals in river water and sediments were studied.•Elevated levels of metals in water and sediments were observed.•Possible effect of metals in sediments was achieved by CF, Igeoand PLI.•Cd and Pb confirmed their serious effect on the aquatic environment.

Sedimentological, palynological data indicate that mangrove community developed under transgressive condition in and around Maheskhali and Kutubdia Island areas during Mid Holocene time (7000 to 5500 years BP) leading to the locally wide spread deposition of organic-rich sediments. During Holocene time global rise and fall of eustatic sea level played an important role not only on the depositional environment but in creating a geomorphic feature on the island. Recurrent occurence of freshwater and mangrove pollen in Maheskhali and Kutubdia Island area indicate that these areas have undergone cyclic marine and non-marine influence. Since the Last Glacial Maximum (about 20,000 years ago), sea level has risen by over 120 m at locations far from present and former ice sheets, as a result of loss of mass from these ice sheets. There was a rapid rise between 15,000 and 6,000 years ago at an average rate of 10 mm/yr. Based on geological data, global average sea level may have risen at an average rate of about 0.5 mm/yr over the last 6000 years and at an average rate of 0.1 to 0.2 mm/yr over the last 3000 years. Vertical land movements are still occurring today as a result of these large transfers of mass from the ice sheets to the ocean. During the last 6000 years, global average sea level variations on time-scales of a few hundred years and longer are likely to have been less than 0.3 to 0.5 m. First transgression was noticed around 6000-5500 cal BP and then a subsequent regression of the bay had been observed from around 5500 cal BP. This was again followed by another small scale transgression episode occurred around 2500—2000 cal BP. So the palynomorph assemblages from the Holocene sediment sample indicate that Maheskhali and Kutubdia Island and its surrounding area was an intertidal environment occupied by mangrove community.

Liquefaction can intensify the destruction caused by an earthquake; thus, a region with high liquefaction potential could be more disastrous. Bangladesh is surrounded by the Indo-Burma Folded Belt in the east, the Dauki Fault and Himalayan Syntaxis in the north that are known to have occurred high magnitude earthquakes (e.g., Mw> 7) in the past. Therefore, assessing seismic hazards in the regions that are economically growing fast is of great interest. Among many other hazard assessment parameters, soil liquefaction potential index (LPI) can be used to assess seismic hazards. In this study, we have assessed the seismic hazard potential for a small town (Moulvibazar) in the northeast Bangladesh documenting liquefaction potential indices for different surface geological units using an earthquake of moment magnitude Mw8 having a peak horizontal ground acceleration (PGA) of 0.36 g. Twenty-five standard penetration test (SPT) boreholes were completed within the study area to obtain SPT-N values for two surface geological units: (1) Holo–Pleistocene low elevated terrace deposits (Zone 1) and (2) Holocene flood plain deposits (Zone 2). Using the SPT-N values, the LPI values have been calculated for the soil profile of each borehole. The LPI values in the town vary from 0 to 42.33, whereas values from 1.42 to 7.52 are in Zone 1 and values from 0 to 42.34 are in Zone 2. It has been predicted that 42% and 78% areas of Zone 1 and Zone 2, respectively, might exhibit surface manifestation of liquefaction. The results of this study can be used for seismic risk management of Moulvibazar town.