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Abstract Existing concrete creep coefficient prediction models have the limitation of not considering the structural characteristics of CFT. For this reason, these models tend to overestimate the creep deformation of CFT. Therefore, in order to overcome the limitations of existing CFT creep experiments, this study proposes a creep-experiment method involving the use of CFT that passively changes the load applied to a single concrete specimen by calculating the stress redistribution between the concrete and a steel tube in CFT based on a step-by-step method. Furthermore, by actually applying the proposed experimental method, a creep experiment of CFT lasting for approximately 163 days was performed and a superficial creep coefficient model of CFT was proposed based on long-term strain data from the experiment. In order to verify the proposed superficial creep coefficient model, it was compared with two design criteria (CEB-FIP and ACI) based on the experimental results of this study and references. As a result, compared to the existing design criteria, the value predicted by the proposed superficial creep coefficient model showed good agreement with the experimental results of this study and the references, proving that the proposed creep-experiment method of CFT and superficial creep coefficient model are reasonable.

A case study was conducted to explore a more rational and robust process for determining the characteristic in-situ compressive strength of concrete structures from core samples. Slabs and girders were obtained from a total of seven bridges, earmarked for demolition due to social and performance considerations. Approximately 600 concrete core samples were extracted from various locations on these bridges. Statistical simulations were carried out using both conventional protocols and a newly proposed method to ascertain the characteristic strength from the cores. This led to a comprehensive discussion on the appropriate sample size, as well as the probabilistic robustness and reliability of the protocols. The proposed method demonstrated the ability to minimize over- or under-estimation of the characteristic strength, providing stable values less affected by fluctuations in core strengths.

Abstract This study investigates the strain softening behavior of high-performance fiber-reinforced cementitious composites (HPFRCCs) under uniaxial compression. HPFRCC mixtures with different compressive strengths ranged from 120 to 170 MPa were prepared. The measurement method of feedback control on loading rate based transverse displacement was applied. Stress–strain and stress−inelastic displacement curves were plotted and analyzed with the results in the literature. It was found that the post-peak energy absorption of HPFRCC considering inelastic deformation was about 3–7 times higher than conventional concrete. Based on the experimental results in the present work, fitting models on post-peak stress–strain/−displacement curves were considering for different aspect ratios proposed.

This study evaluates land cover classification accuracy through adjustments to the deep learning model (DLM) training process, including variations in loss function, the learning rate scheduler, and the optimizer, along with diverse input dataset compositions. DLM datasets were created by integrating surface reflectance (SR) spectral data from satellite imagery with textural information derived from the gray-level co-occurrence matrix, yielding four distinct datasets. The U-Net model served as the baseline, with models A and B configured by adjusting the training parameters. Eight land cover classifications were generated from four datasets and two deep learning training conditions. Model B, utilizing a dataset comprising spectral, textural, and terrain information, achieved the highest overall accuracy of 90.3% and a kappa coefficient of 0.78. Comparing different dataset compositions, incorporating textural and terrain data alongside SR from satellite imagery significantly enhanced classification accuracy. Furthermore, using a combination of multiple loss functions or dynamically adjusting the learning rate effectively mitigated overfitting issues, enhancing land cover classification accuracy compared to using a single loss function.

Nanocellulose (NC) has emerged as a promising biodegradable material with applications in various industrial fields owing to its high mechanical strength, thermal stability, and eco-friendly properties. Traditional methods for isolating NC from wood-based biomass (WB) involve high energy consumption and extensive chemical usage, leading to environmental and sustainability concerns. This study explored an alternative approach to isolate NC from seaweed-based biomass (SB) (SNC), which contains fewer non-cellulosic components and a higher cellulose content than WB, thereby yielding a more efficient e-isolation process. We employed a combination of modified-acid solution and electron beam (E-beam) technology to isolate NC from SB. The E-beam process enhanced the crystallinity while reducing the particle size, thus facilitating NC isolation with reduced environmental impact and processing time. Moreover, our method significantly reduced the need for harsh chemical reagents and energy-intensive processes, which are typically associated with traditional NC isolation methods. We fabricated biodegradable films with improved mechanical properties using NC as a reinforcing agent in polymer composites, thereby demonstrating the potential of NC-based materials for various applications. Therefore, our proposed approach offers a sustainable and efficient method for NC isolation and serves as a guide for the development of eco-friendly industrial processes. Our findings contribute to ongoing efforts to create sustainable materials and reduce the environmental footprint of the manufacturing industry.

Abstract The extra-articular distal humerus plate (EADHP) has been widely used for surgical treatment of distal humerus shaft fracture (DHSF). However, the surgical approach, fixation methods, and implant positions of the EADHP remain controversial owing to iatrogenic radial nerve injury and complaints such as skin irritation related to the plate. Anterior plating with a modified (upside-down application) proximal humerus locking plate (PHILOS) has been proposed as an alternative, However, research on its biomechanical performance remain insufficient and were mostly based on retrospective studies. This study quantitatively compared and evaluated the biomechanical performance between posterior plating with the EADHP and anterior plating with a modified PHILOS using finite element analysis (FEA). The FEA simulation results that both the EADHP and PHILOS had adequate biomechanical performance and stability under axial, bending, and varus force load conditions. The PHILOS has a fixed stability comparable to that of the EADHP, and fixation was achieved using only four locking screws within a fixed range of 30 mm just above the olecranon fossa. The results show that the PHILOS could be an option for the fixation of a DHSF when considering the dissection range and complaints (e.g. skin irritation) associated with the EADHP.

A smart thinning operation refers to an advanced method of selecting and cutting trees to be thinned based on digitally captured forest information. In smart thinning operations, workers use the coordinates of individual trees to navigate to the target trees for thinning. However, it is difficult to accurately locate individual trees in a forest stand covered with a canopy, necessitating a precise real-time positioning system that can be used in the forest. Therefore, this study aimed to evaluate the applicability of the global navigation satellite system real-time kinematic (GNSS-RTK) device in a forest stand through analysis of its positioning accuracy within the forest environment and evaluation of the operational range of the single-baseline RTK based on analysis of the positioning precision and radio signal strength index (RSSI) change with increasing distance from the base station. The results showed that the root mean square error (RMSE) of the horizontal positioning error was highly accurate, with an average of 0.26 m in Larix kaempferi stands and 0.48 m in Pinus koraiensis stands. The RSSI decreased to a minimum of −103.3 dBm within 1 km of distance from the base station; however, this had no significant impact on the horizontal positioning precision. The conclusion is that the GNSS-RTK is suitable for use in smart thinning operations.

Abstract Background We investigated the efficacy of a maxillary Jackson-Pratt (J-P) suction drain for preventing maxillary sinus hematoma and facial swelling after maxillary Le Fort I osteotomy (LF1). Methods We retrospectively evaluated 66 patients who underwent LF1 at a single institution. Of these, 41 had a J-P suction tube inserted in the mandible and maxilla (maxillary insertion), and 25 had a J-P drain inserted in the mandible only (no maxillary insertion). Facial CT was obtained before and 4 days after surgery. We compared mean midfacial swelling and maxillary sinus haziness by t test and examined correlations between bleeding amount and body mass index (BMI). Results For the maxillary-insertion group, the ratio of total maxillary sinus volume to haziness (57.5 ± 24.2%) was significantly lower than in the group without maxillary drain insertion (65.5% ± 20.3; P = .043). This latter group, however, did not have a significantly greater midfacial soft tissue volume (7575 mm3) than the maxillary-insertion group (7250 mm3; P = .728). BMI did not correlate significantly with bleeding amount or facial swelling. Conclusions Suction drainage in the maxilla reduced maxillary sinus haziness after orthognathic surgery but did not significantly reduce midfacial swelling.

Abstract Mung bean starch (MBS)-based edible films with incorporation of guar gum (GG) and sunflower seed oil (SSO) were developed in this study. MBS, GG, and SSO were used as the main filmogenic biopolymer, thickener, and hydrophobicity-imparting substance, respectively. To investigate the effect of SSO content on the physicochemical, mechanical, and optical properties of the films, they were supplemented with various concentrations (0, 0.5, 1, and 2%, w/w) of SSO. Increasing SSO content tended to decrease tensile strength, elongation at break, crystallinity, water solubility, and the water vapor permeability; in contrast, it increased the oxygen transmission rate and water contact angle. Consequently, the incorporation of SSO into the matrix of MBS-based films decreased their mechanical strength but effectively enhanced their water-resistance properties. Therefore, the MBS-based film developed here can be properly used as an edible film in settings that require high water-resistance properties but do not call for robust mechanical strength.

Objectives Heavy metals caused by industrialization have affected human society for several decades. Because of their toxicity for humans, lots of heavy metal treatments have been developed. However, many of those treatments have economic considerations and environmental disadvantages. This work explored an experimental assessment of adsorption of heavy metals using starfish (SF) biochar through quantitative and qualitative characterization and batch-tests. Methods Biochar (NACSF) was produced at 300℃ for 2 h in anaerobic conditions. The NACSF was characterized with XRD, XRF, FT-IR, SEM-EDX and elemental analyses. Moreover, batch-tests for each heavy metal using NACSF were conducted with ICP-OES analyses in order to evaluate the adsorption characteristics. Results and Discussion Based on the characterization results, the NACSF consisted of carbon and CaCO3 mainly. The adsorption rates of Pb, Cu, Zn and Cd decreased in the following order: Pb≫Cu>Zn≥Cd. Moreover, the Langmuir equation fit all adsorption data better than the Freundlich equation. Also, due to the alkalinity of NACSF, the measured pH values of all experimental groups were approximately 7~8. Conclusions The NACSF treatment was the most effective for Pb removal and it was determined that precipitation and surface adsorption were the most likely mechanisms for Pb removal. Thus, NACSF derived from starfish could be an cost-effective and eco-friendly treatment for heavy metal contaminated wastewater.

Poly(ionic liquid)s (PILs) are used in many electrochemical energy storage/conversion devices owing to their favorable physical properties. Therefore, PIL binders have been examined as polymeric binders for electrodes in energy storage systems (ESSs) and have shown superior performance. Several innovative technologies have been developed to improve the properties of polymers, with cross-linking being the most effective and easy strategy to achieve this. In this study, we designed a breakthrough complex cross-linking and composite technique that could successfully develop the physical properties of a polymer in a simple one-step process. Additionally, the technique could improve the thermal stability and mechanical properties of the polymer. The proposed polymeric binder showed better adhesion, higher capacitance, and good energy density with improved cyclic stability compared to that shown by conventional polyvinylidene fluoride (PVDF). This study revealed that cross-linked networks in polymeric binders are long-cycle-life features for electrochemical redox capacitors.

The design of a novel binder is required for high-capacity silicon anodes, which typically undergo significant changes during charge/discharge cycling. Hence, in this study, a stable network structure was formed by combining tannic acid (TAc), which can be cross-linked, and poly(acrylic acid)(PAA) as an effective binder for a silicon (Si) anode. TAc is a phenolic compound and representative substance with antioxidant properties. Owing to the antioxidant ability of the C-PAA/TAc binder, side reactions during the cycling were suppressed during the formation of an appropriate solid–electrolyte interface layer. The results showed that the expansion of a silicon anode was suppressed compared with that of a conventional PAA binder. This study demonstrates that cross-linking and antioxidant capability facilitate binding and provides insights into the behavior of binders for silicon anodes. The Si anode with the C-PAA/TAc binder exhibited significantly improved cycle stability and higher Coulombic efficiency in comparison to the Si anode with well-established PAA binders. The C-PAA/TAc binder demonstrated a capacity of 1833 mA h g−1Si for 100 cycles, which is higher than that of electrodes fabricated using the conventional PAA binder. Therefore, the C-PAA/TAc binder offers better electrochemical performance.

The effects of different nutrient solution quantities on growth, physicochemical, nutritional, and postharvest qualities of lettuce were investigated. Two differently pigmented Korean leaf lettuce cultivars “Geockchima” and “Cheongchima” were grown in soilless perlite culture supplied with 250, 500, 1000, and 2000 mL·d−1·plant−1 nutrient solutions. Several growth parameters (plant height, leaf number, fresh weight, dry matter) were evaluated. The highest lettuce growth was observed when plants were supplied with 1000 mL·d−1·plant−1. Cultivating lettuces in the lowest nutrient solution quantity showed higher dry matter, crude fiber, osmolality, chlorophyll, and anthocyanin contents. Upon increasing the nutrient solution, the crispiness, greenness, and levels of ascorbic acid, nitrogen, and potassium, increased, while phosphorus and magnesium were unaffected, and calcium content declined. Postharvest qualities were better maintained in lettuces irrigated with the least amount of nutrient solution, extending their shelf life. We conclude that lettuce can be grown with 1000 mL·d−1·plant−1 for higher yield, and short-term storage and/or transportation. However, when lettuces need to be stored for a certain period, such as long-distance shipment, they should be cultivated with a limited nutrient solution, which requires further detailed investigation. The results of this study can be applied for distributing, storing, transporting, and marketing lettuce.

The effects of CO2 pretreatment before cold storage on tomato quality were investigated using physicochemical and transcriptome changes. Harvested tomatoes were treated with 30% or 60% CO2 for 3 h before storage at 4 °C for 14 d (cold storage), followed by transfer to 20 °C for 8 d (ambient conditions). The CO2-treated fruits were firmer with a better appearance than untreated fruits, even after being transferred from 4 °C storage to 20 °C for 8 d. CO2 pretreatment coupled with cold storage synergistically delayed tomato ripening by reducing respiration and lowering lycopene production. The tomatoes treated with 30% and 60% CO2 had fewer pits than untreated fruits after cold storage, even after being transferred to ambient conditions. Moreover, the 60% CO2 treatment significantly suppressed the decay rate. Transcriptome and metabolome functional enrichment analyses commonly showed the involvement of CO2-responsive genes or metabolites in sucrose and starch metabolism, as well as biosynthesis of secondary metabolites—in particular, glycolysis reduction. The most frequently detected domain was the ethylene-responsive factor. These results indicate that altered ethylene biosynthesis and ethylene signaling, via ethylene-responsive transcription factors and respiration-related pathways, appear to control CO2-induced fruit quality.

Chilling injury (CI), which causes seed browning in pepper, may arise following long-term cold storage, and is a major cause of postharvest losses. To explore potential strategies of minimizing the associated postharvest losses, the present study investigated the optimal pepper harvest time that could reduce levels of seed browning, in addition to the relationship between fruit maturity and seed browning. Fruits harvested 15 days after flowering (DAF) were sensitive to cold storage at 4 °C and exhibited 100% seed browning (CI index, 4.0); in contrast, the seed browning rate of fruits harvested 35 DAF was 10% (CI index, 0.4) within 7 days of cold storage. Seed antioxidant activity was higher in seeds harvested at early stages (15 DAF to 20 DAF) than in seeds harvested at later stages (40 DAF to 50 DAF) at the beginning of storage. Pericarps of fruit harvested at 50 DAF exhibited the highest antioxidant activity. Lipoxygenase, catalase, and peroxidase activity, and the expression levels of cell wall-related genes, pectin methylesterase-like protein, and endo-β-1,4-glucanase were higher in seeds of immature fruit harvested 15 DAF than in seeds of mature fruit harvested 35 DAF. The seeds of the fruit harvested 35 DAF were fully developed with the seed coat separated from the endosperm and did not turn brown under low-temperature storage. The lack of seed browning observed in mature fruit under low-temperature storage could be attributed to physical protection provided by the seed coat rather than cold stress resistance conferred by antioxidants.

Concrete-filled tubular (CFT) columns have been widely used as structural members because CFT columns synergize the advantages of steel and concrete resulting in high strength, high ductility, and large energy dissipation capacity. Numerous studies have been performed to understand the behavior of CFT columns. However, the behavior of CFT columns remains uncertain due to their inelastic behavior and uncertain confinement effects, especially when failure occurs. In addition, diaphragms, which are generally installed, make it more complicated to understand the behavior of CFT columns. The purpose of this study is to investigate the effects of the diaphragms on the failure behavior of the CFT columns. To this end, eighteen rectangular CFT columns were tested with five different loading cases. The experimental results suggest that the size of the diaphragm has significant effects on the compressive strength and toughness of the CFT columns. In order to facilitate the proper composite actions of steel and concrete, the size of a diaphragm has to be at least three-quarters of the cross-sectional area.

Oriental melons have a relatively short shelf life as they are harvested during the summer season and susceptible to cold-induced injuries. Typical chilling injury when stored at 4 °C is expressed as browning of the fruit suture. To prolong the shelf life and reduce browning of the fruit, the effects of modified atmosphere packaging (MAP), X-tend modified atmosphere (MA)/modified humidity (MH) bulk packaging (XF), and polyethylene (PE) packaging, on oriental melons were investigated during storage at 4 °C and 10 °C for 14 days and under retail display conditions at 20 °C. The O2 concentrations in PE packages stored at 4 °C and 10 °C ranged from 17.4 to 18.5%, whereas those in XF packages were reduced to 16.3–16.6%. The CO2 content of XF package (4.2–4.6%) was higher than that of PE package (1.4–1.9%) stored at 4 °C or 10 °C. Relative humidity (RH) saturated in the PE packages but not in the XF packages after seven days of storage. Furthermore, PE packages performed better at maintaining melon weight and firmness than XF packages during storage at 10 °C for 14 days and under retail display conditions at 20 °C. PE and XF packages effectively reduced the browning index of the peel and white linear sutures of oriental melons compared with the unpackaged control during cold storage at 4 °C, and this observation was maintained at the retail display condition at 20 °C. The enhanced CO2 levels, reduced O2 levels, and optimal RH values that were provided by the MAP, prevented the browning symptoms, and improved the marketability and shelf life of oriental melons.

To investigate the effects of packaging on the quality aspects of radish, Korean radish roots (Raphanus sativus L. var. Kwandong) were stored at 0°C after different packaging treatments such as keeping in paper cartoon box (control), keeping in plastic crates (PC), packaging with micro perforated HDPE film in PC (HDPE + PC), curing followed by keeping in PC (Curing + PC), and curing followed by packaging with micro perforated HDPE film in PC (Curing + HDPE + PC). Weight losses of radish roots were remarkably lower (

Study Design: Retrospective case-control study. Purpose: This study aimed to investigate the preventive effect of thrombin-containing local hemostatics (TCLH) on postoperative spinal epidural hematoma (POSEH) in biportal endoscopic spinal surgery (BESS). This study compared the incidence of morphometric and symptomatic POSEH with or without TCLH in BESS. Overview of Literature: POSEH is reported not uncommon in BESS when compared with conventional spine surgery (CSS). TCLH achieves hemostasis with a high success rate in CSS. However, few studies have examined the effect of TCLH on BESS. Methods: Patients with and without TCLH were assigned to groups A and B, respectively. POSEH between the two groups was compared morphometrically and symptomatically. The risk factors for symptomatic and morphometric POSEH in BESS were identified. Results: The morphometric POSEH was greater in group B, and the difference was significant (p =0.019). The incidence of symptomatic POSEH was lower in group A with 4.6% (5/109) than in group B with 9.5% (9/95); however, the rate was not significantly different (p =0.136). The morphometric POSEH was classified into two small (hG1 and hG2) and large (hG3 and hG4) and were compared between groups A and B, and the difference was significant (p =0.02). In the multivariable logistic regression, nonuse of TCLH (p =0.004) and preoperative diagnosis of stenosis (p =0.016) were variables found to be significant risk factors of morphometric POSEH. Conclusions: Severe compression of the thecal sac by POSEH is more common in patients without TCLH. The risk of hematoma formation was higher when bilateral decompression was needed and the cut bone surface was more exposed. [ABSTRACT FROM AUTHOR]