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The use of fiber-reinforced polymer (FRP) strips as an external strengthening method has gained widespread acceptance for enhancing the capacity of aging reinforced concrete (RC) beams. Despite extensive research and practical applications, there exist unresolved issues necessitating further investigation, including interface bonding, failure mechanisms, and the development of accurate predictive models for shear strength, considering diverse parameters. This paper systematically reviews shear strength formulas applied in the strengthening of RC beams using FRP strips. An extensive experimental dataset is compiled from diverse sources to support the analysis. Utilizing this dataset, a novel ensemble learning model is developed for predicting the shear strength contributed by FRP strips. Following the training of this model, the important score of each input parameter is also assessed. The findings presented herein contribute to a deeper understanding of the strengthening effectiveness of FRP strips on RC beams.

Abstract Repetitive mild traumatic brain injury (r-mTBI) has increasingly become recognised as a risk factor for the development of neurodegenerative diseases, many of which are characterised by tau pathology, metal dyshomeostasis and behavioural impairments. We aimed to characterise the status of tau and the involvement of iron dyshomeostasis in repetitive controlled cortical impact injury (5 impacts, 48 h apart) in 3-month-old C57Bl6 mice at the chronic (12-month) time point. We performed a battery of behavioural tests, characterised the status of neurodegeneration-associated proteins (tau and tau-regulatory proteins, amyloid precursor protein and iron-regulatory proteins) via western blot; and metal levels using bulk inductively coupled plasma-mass spectrometry (ICP-MS). We report significant changes in various ipsilateral iron-regulatory proteins following five but not a single injury, and significant increases in contralateral iron, zinc and copper levels following five impacts. There was no evidence of tau pathology or changes in tau-regulatory proteins following five impacts, although some changes were observed following a single injury. Five impacts resulted in significant gait deficits, mild anhedonia and mild cognitive deficits at 9–12 months post-injury, effects not seen following a single injury. To the best of our knowledge, we are the first to describe chronic changes in metals and iron-regulatory proteins in a mouse model of r-mTBI, providing a strong indication towards an overall increase in brain iron levels (and other metals) in the chronic phase following r-mTBI. These results bring to question the relevance of tau and highlight the involvement of iron dysregulation in the development and/or progression of neurodegeneration following injury, which may lead to new therapeutic approaches in the future.

In this study, the efficiency of integration between Taguchi and TOPSIS in multi-response optimi-zation of powder mixed electrical discharge machining (PMEDM) process was evaluated. The in-put parameters, such as workpiece and tool electrode material, polarity, pulse on time (ton), pulse off time (toff), Current (I) and powder concentration have been selected to optimize two responses; namely surface roughness (Ra) and surface hardness (HV). The results show that titanium powder mixed dielectric fluid improves multi-response optimization efficiency in PMEDM. In addition, machining conditions, such as tool electrode material, powder concentration, pulse on time, polarity, current density, A×G and B×G interactions play a very important role on S/N ratio of C* whereby powder concentration has the strongest influence. TOPSIS -Taguchi is a potential method for multi-response optimization in PMEDM. However, the optimal results using ANOVA analysis show that there is a necessity to have more studies in TOPSIS-Taguchi to improve the in-tegration efficiency between two methods for optimizing multiple responses in PMEDM.

Linker for Activation of T cells (LAT) is an adapter protein that is essential for T cell function. Knock-in mice with a LAT mutation impairing calcium flux develop a fatal CD4+ lymphoproliferative disease. miR-155 is a microRNA that is correlated with hyperproliferation in a number of cancers including lymphomas and leukemias and is overexpressed in mutant LAT T cells. To test whether miR-155 was merely indicative of T cell activation or whether it contributes to lymphoproliferative disease in mutant LAT mice, we interbred LAT mutant and miR-155-deficient mice. miR-155 deficiency markedly inhibited lymphoproliferative disease by stimulating BIM-dependent CD4+ T cell apoptosis, even though ERK activation and T cell proliferation were increased in double mutant CD4+ T cells. Bim/Bcl2l11 expression is activated by the forkhead transcription factor FOXO3. Using miR-155-deficient, LAT mutant T cells as a discovery tool, we found two connected pathways that impact the nuclear translocation and activation of FOXO3 in T cells. One pathway is mediated by the inositide phosphatase SHIP-1 and the serine/threonine kinases AKT and PDK1. The other pathway involves PAK1 and JNK kinase activation. We define crosstalk between the two pathways via the kinase mTOR, which stabilizes PAK1. This study establishes a role for PAK1 in T cell apoptosis, which contrasts to its previously identified role in T cell proliferation. Furthermore, miR-155 regulates the delicate balance between PAK1-mediated proliferation and apoptosis in T cells impacting lymphoid organ size and function.

Thermal management presents an increasing challenge in future engineering systems, especially in applications like combined cycle precooling, waste heat recovery, and innovative propulsion systems. These systems face a growing demand for managing higher heat loads while coping with limited heat sink. Central to these thermal management systems is the heat exchanger, with microtube heat transfer emerging as a promising solution for future technologies. Microtube heat exchangers are becoming popular owing to their ability to significantly enhance the heat transfer surface area while maintaining a compact core volume. As the demand for high-performance, lightweight heat exchangers escalates, microtube heat exchangers are being designed to be increasingly compact yet highly loaded. This trend poses significant challenges to their structural integrity, particularly under harsh operational conditions. Flow-induced vibrations, a critical concern in the design of tubular heat exchangers, can lead to tube failures, compromising the safe operation of engineering systems. While the flow-induced vibrations of conventional-sized heat exchangers have been extensively studied, there is a noticeable gap in the research on similar phenomena in microtube heat exchangers. This paper details ongoing research at Reaction Engines Ltd (REL) to aid the design of safe and robust heat exchangers, focusing on the flow-induced vibrations in microtube heat exchangers and utilizing a cutting-edge laser vibrometry test facility. A predictive model, employing an unsteady flow simulation approach and eigenvalue analysis, has been formulated. A key observation is the distinctive coupled transverse-streamwise orbital motion in microtube heat exchangers, differing from the predominantly transverse direction of failures in conventional-sized heat exchangers. [ABSTRACT FROM AUTHOR]

Brush seals offer a superior sealing effectiveness compared to labyrinth seals. However, widespread use of brush seals is constrained by deleterious behaviors such as pressure-stiffening and hysteresis. For the latter, the bristles bend during the shaft incursion process and do not fully recover during the shaft retraction process. An opening gap is created, which increases seal leakage unless the pressure load drops to a certain level. In this work, analytical and numerical models based on a single bristle are proposed to capture the seal's response to shaft displacement with and without pressure loading. The models are validated using static stiffness tests at an unpressurized condition from literature. The main results show that modeling of the backing ring friction is essential to capture the bristle hang-up behavior. Shaft friction dominates at unpressurized conditions, while backing ring friction dominates at high pressure loading. An expression for shaft hang-up displacement has been derived. A sensitivity study shows that seals with shallow lay angle, short bristle length, and large bristle diameter are less prone to hang-up problems. The models developed in the present framework have been shown to qualitatively capture the pressure stiffening, hysteresis, bristle hang-up, and shaft rotation effects. [ABSTRACT FROM AUTHOR]

Plectranthus amboinicus (Lamiaceae) is a medicinal plant widely cultivated and naturalized in the tropics of the Old and New World, with a history of use in folk medicine. However, there has been no prior investigation into the chemical composition and biological properties of this species in the Dak Lak Province, Vietnam. In this study, the essential oil extracted from P. amboinicus, collected in Buon Ma Thuot City in Dak Lak Provincfe was analyzed using gas chromatography-mass spectrometry (GC-MS). A total of 89 compounds were identified, constituting 0.62% of the oil; the major constituents included 2,3,5,6-tetramethylphenol (67.94%), caryophyllene (9.74%), trans-a-bergamotene (5.82%), α-humulene (3.20%), γ-terpinene (2.5%), o-cymene (1.90%), and terpinen-4-ol (1.14%). Notably, the carvacrol content exceeded previously reported values. In addition, P. amboinicus showed strong antibacterial activity against Escherichia coli using the agar disc diffusion method, with approximately 88.35% inhibition and a diameter of 47.3 mm. The antioxidant capacity of the essential oil was evaluated with the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, yielding an antioxidant efficiency of 89.21% and an IC50 value of 44.15 µg/mL. This demonstrates the high pharmaceutical potential of the P. amboinicus species grown in Vietnam. [ABSTRACT FROM AUTHOR]

Ocimum basilicum Linn (Lamiaceae), also known as sweet Basil, is a widely recognized medicinal plant. Although this species has been extensively researched on its biological activities and chemical composition in some Provinces of Vietnam, however, studies on the chemical composition and biological properties of this species growing in Dak Lak Province have not been investigated to date. The chemical composition of the essential oil from O. basilicum, collected in Vietnam, was analyzed using the gas chromatography-coupled mass spectrometry (GC-MS) method. The essential oil content yielded 0.55%, with 34 compounds being determined. Among them, the major constituents (%) were as follows: estragole (73.66%), eucalypto (6.41%), trans-α-bergamotene (3.97%), linalool (2.25%), fenchol (1.64%), 2-isopropyl-5-methyl-9-methylene-bicyclo[4.4.0]dec-1-ene (1.47%), 1,3,6-octatriene,3,7-dimethyl-(Z) (1.36%), (+)-2-bornanone (1.34%), and methyl eugenol (1.11%). Furthermore, an antibacterial test on O. basilicum essential oil was conducted, and the results demonstrated strong antibacterial activity against Escherichia coli with an inhibition zone of 18.6 ± 0.9 mm and the lowest minimum inhibitory concentration (MIC) value (4.3 ± 0.2 mg/mL). Additionally, the antioxidant capacity of Basil essential oil was evaluated using the 2,2-diphenyl-1-picryhydrazyl (DPPH) method. The antioxidant efficiency of essential oil was determined with an IC50 of 6.5 ± 0.3 μg/mL, compared with butylated hydroxytoluene (BHT) with an IC50 value of 6.1 ± 0.1 μg/mL. These findings indicate that O. basilicum grown in Vietnam possesses a high natural potential for pharmaceutical applications. [ABSTRACT FROM AUTHOR]

Nghiên cứu thực hiện khảo sát khả năng kháng vi khuẩn gây mụn từ tinh dầu của Curcuma involucrata thu hái từ tỉnh Long An. Tinh dầu được chiết bằng phương pháp chưng cất lôi cuốn hơi nước. Hoạt tính kháng khuẩn của dược liệu được khảo sát bằng các phương pháp: đĩa giấy khuếch tán; pha loãng trong môi trường rắn (MIC), trải đĩa (MBC), đĩa ba ngăn (pha hơi). Thành phần hóa học của tinh dầu được xác định bằng phương pháp sắc ký khí ghép khối phổ (GC-MS). Hiệu suất chiết tinh dầu là 0,29%. Kết quả xác định thành phần hóa học của tinh dầu bằng GC-MS cho thấy sự hiện diện của ít nhất 28 chất, trong đó hai hợp chất chính là isoterpinolen (29,65%) và β-ocimen (11,60%). Tinh dầu thể hiện tác dụng ức chế tốt nhất trên Staphylococcus aureus với MIC = 0,16 µL/mL và tác dụng ức chế trung bình trên Propionibacterium acnes với MIC = 0,63 µL/mL. Tinh dầu thân rễ ngải năm ông thích hợp đối với chế phẩm dạng kem, tác động tại chỗ trong điều trị mụn vì cho hoạt tính kháng khuẩn trên pha rắn tốt hơn so với pha hơi.

Background and Purpose: Traumatic brain injury (TBI) remains a leading cause of mortality and morbidity in young adults. The role of iron in potentiating neurodegeneration following TBI has gained recent interest as iron deposition has been detected in the injured brain in the weeks to months post‐TBI, in both the preclinical and clinical setting. A failure in iron homeostasis can lead to oxidative stress, inflammation and excitotoxicity; and whether this is a cause or consequence of the long‐term effects of TBI remains unknown. Experimental Approach: We investigated the role of iron and the effect of therapeutic intervention using a brain‐permeable iron chelator, deferiprone, in a controlled cortical impact mouse model of TBI. An extensive assessment of cognitive, motor and anxiety/depressive outcome measures were examined, and neuropathological and biochemical changes, over a 3‐month period post‐TBI. Key Results: Lesion volume was significantly reduced at 3 months, which was preceded by a reduction in astrogliosis, microglia/macrophages and preservation of neurons in the injured brain at 2 weeks and/or 1 month post‐TBI in mice receiving oral deferiprone. Deferiprone treatment showed significant improvements in neurological severity scores, locomotor/gait performance and cognitive function, and attenuated anxiety‐like symptoms post‐TBI. Deferiprone reduced iron levels, lipid peroxidation/oxidative stress and altered expression of neurotrophins in the injured brain over this period. Conclusion and Implications: Our findings support a detrimental role of iron in the injured brain and suggest that deferiprone (or similar iron chelators) may be promising therapeutic approaches to improve survival, functional outcomes and quality of life following TBI. [ABSTRACT FROM AUTHOR]

Fast (Type II) muscle fibers are affected early and disproportionately in dystrophinopathies. Sevasemten (EDG-5506) is an orally administered, once daily, investigational product that modulates fast skeletal muscle myosin and, in DMD disease models, decreased muscle damage biomarkers and fibrosis while increasing muscle strength and activity. ARCH is a 24-month Phase 1b open-label study of sevasemten, assessing safety, pharmacokinetics, biomarkers of muscle damage and functional measures in adults with Becker. Twelve ambulatory adults with Becker received daily oral doses of sevasemten. At baseline, North Star Ambulatory Assessment (NSAA) ranged from 5 to 31 (mean 15.5). Decreased muscle mass was evident by low serum creatinine and DXA lean muscle mass. After 24 months, sevasemten was well tolerated without serious adverse events, withdrawals due to AEs, or dose modifications. Rapid (within 1-2 months) reductions in biomarkers of muscle damage were sustained to 24 months, including creatine kinase, myoglobin and fast skeletal muscle troponin I. Alongside acute and chronic biomarker changes, trends toward functional improvement were noted with NSAA with a mean change of -0.2 versus an expected decline of -2.4 or more as predicted from natural history (Bello 2016, Van de Velde 2021, De Wel 2024). The 100-meter timed test and grip strength were unchanged over 24 months. In summary, sevasemten was well tolerated with rapid and sustained reductions in biomarkers of muscle damage. Treatment resulted in acute and sustained reductions in muscle damage biomarkers. Functional improvements compared to the expected natural history decline in the NSAA score were observed. Phase 2 trials in BMD and DMD are ongoing (NCT05291091 and NCT05540860) including a pivotal cohort in Becker. [ABSTRACT FROM AUTHOR]

Bài báo nhằm xác định khả năng phù hợp đất đai về định tính và định lượng làm cơ sở bố trí sử dụng đất nông nghiệp cho huyện Vĩnh Thuận. Chín cuộc PRA (Participatory Rural Appraisal) được tiến hành thực hiện đối với nhà quản lý và người dân trực tiếp canh tác nông nghiệp để xác định các điều kiện về tự nhiên, kinh tế và tình hình sản xuất nông nghiệp của địa phương. Bên cạnh đó, phương pháp đánh giá đất đai của Food and Agriculture Organization - FAO (1976 và 2007) được áp dụng để xác định khả năng phù hợp đất đai về tự nhiên và kinh tế cho các kiểu sử dụng đất chính của huyện dưới sự hỗ trợ của công cụ GIS để xây dựng các bản đồ chuyên đề. Kết quả đã xác định được 07 vùng thích nghi tự nhiên và 12 vùng thích nghi về kinh tế cho 05 kiểu sử dụng đất bao gồm lúa 2 vụ, lúa 2 vụ-màu, lúa-tôm, thuỷ sản lợ và chuyên khóm. Căn cứ vào khả năng phù hợp về tự nhiên và định lượng kinh tế, kết hợp định hướng phát triển của địa phương và trên cơ sở tham vấn ý kiến của người dân, 06 vùng sản xuất nông nghiệp đã được xây dựng cho huyện Vĩnh Thuận đến năm 2030 mang tính bền vững, thích ứng với biến đổi khí hậu.

Empirical formulas play a pivotal role in the assessment of bond strength between Fiber Reinforced Polymer (FRP) bars and concrete. Although some studies have explored the applicability of existing formulas, a comprehensive investigation on a broad scale, encompassing diverse types of FRP bars, and their application in both normal and high-strength/ultra-high-strength concrete, is lacking. This study aims to consider the application scope of seven existing formulas for assessing the bond strength of diverse FRP bars in various concrete types, including normal, high-strength, and ultra-high-strength concrete. The evaluation of formula applicability utilizes a dataset comprising 1019 pull-out test specimens from 34 recent studies. In the dataset, 447 specimens fall within the typical application scope, involving Glass (G) FRP bars with diameters ranging from 8 to 16 mm embedded in normal concrete. The remaining specimens cover broader application scenarios, including the use of high-strength or ultra-high-strength concrete, smaller or larger bar diameters, and the incorporation of other bar types such as Carbon (C) FRP and Basalt (B) FRP. The results highlight variations in the correlation between calculated values and experimental outcomes across different formulas. Appropriate safety coefficients have been applied to all seven formulas, expanding their applicability to a wider design spectrum.

Abstract The aims of this study are to predict the stock price trend in the stock market in an emerging economy. Using the Long Short Term Memory (LSTM) algorithm, and the corresponding technical analysis indicators for each stock code include: simple moving average (SMA), convergence divergence moving average (MACD), and relative strength index (RSI); and the secondary data from VN-Index and VN-30 stocks, the research results showed that the forecasting model has a high accuracy of 93% for most of the stock data used, demonstrating the appropriateness of the LSTM model and the test set data is used to evaluate the model’s performance. The research results showed that the forecasting model has a high accuracy of 93% for most of the stock data used, demonstrating the appropriateness of the LSTM model in analyzing and forecasting stock price movements on the machine learning platform.

This paper presents an innovative approach that integrates a fixed-time control (FTC) algorithm with an improved sparrow search algorithm (ISSA) to enhance the trajectory tracking accuracy of a two-degree-of-freedom (two-DOF) robotic arm. The FTC algorithm, which incorporates barrier Lyapunov function (BLF) and adaptive neural network strategies, ensures rapid convergence, effective vibration suppression, and the robust handling of system uncertainties and input saturation. The ISSA, inspired by the foraging behavior of sparrows, improves search efficiency through dynamic weight adjustments and chaotic mapping, balancing global and local search capabilities. By optimizing control parameters, ISSA minimizes tracking errors. Simulation results demonstrate that the combined FTC and ISSA approach significantly reduces tracking errors and improves response speed compared to the use of FTC alone, underscoring its potential for achieving high-precision control in robotic arms and offering a promising direction for precise robotic control applications.

A utility theory useful for decision-making in the presence of uncertainty that is assessed by possibility theory is suggested.