Search Results (148)

Background/Objectives: Chemotherapy-induced alopecia is a common and distressing side effect of cancer treatment, significantly impacting patients’ psychological well-being. Nanocarriers offer a promising strategy for targeted drug delivery to hair follicles, while chitosan nanoparticles have demonstrated hair-growth-promoting properties. This study explores the potential of chitosan nanoparticles as a topical delivery system for five pharmacological agents—phenobarbital, pioglitazone, rifampicin, N-acetylcysteine, and tacrolimus—to prevent chemotherapy-induced alopecia. Methods: Drug-loaded chitosan nanoparticles were prepared using the ionic gelation technique and characterized by particle size, zeta potential, entrapment efficiency, FT-IR spectroscopy, and TEM imaging. Their efficacy was assessed in a cyclophosphamide-induced alopecia model in C57BL/6 mice through macroscopic observation, histopathological examination, and scanning electron microscopy of regrown hair. Results: The prepared particles were spherical, cationic, and between 205 and 536 nm in size. The entrapment efficiencies ranged from 8% to 63%. All five drugs mitigated follicular dystrophy, shifting the hair follicle response from dystrophic catagen to dystrophic anagen. Phenobarbital demonstrated the most significant hair regrowth and quality improvements, followed by N-acetyl cysteine and pioglitazone. Tacrolimus showed moderate efficacy, while rifampicin was the least effective. Conclusions: These findings suggest that phenobarbital-loaded chitosan nanoparticles represent a promising approach for the prevention and treatment of chemotherapy-induced alopecia, warranting further investigation for clinical applications. Full article

Navigational aids play a vital role in enhancing the mobility and independence of blind and visually impaired (VI) individuals. However, existing solutions often present challenges related to discomfort, complexity, and limited ability to provide detailed environmental awareness. To address these limitations, we introduce SnapStick, an innovative assistive technology designed to improve spatial perception and navigation. SnapStick integrates a Bluetooth-enabled smart cane, bone-conduction headphones, and a smartphone application powered by the Florence-2 Vision Language Model (VLM) to deliver real-time object recognition, text reading, bus route detection, and detailed scene descriptions. To assess the system’s effectiveness and user experience, eleven blind participants evaluated SnapStick, and usability was measured using the System Usability Scale (SUS). In addition to the 94% accuracy, the device received an SUS score of 84.7%, indicating high user satisfaction, ease of use, and comfort. Participants reported that SnapStick significantly improved their ability to navigate, recognize objects, identify text, and detect landmarks with greater confidence. The system’s ability to provide accurate and accessible auditory feedback proved essential for real-world applications, making it a practical and user-friendly solution. These findings highlight SnapStick’s potential to serve as an effective assistive device for blind individuals, enhancing autonomy, safety, and navigation capabilities in daily life. Future work will explore further refinements to optimize user experience and adaptability across different environments. Full article

This study investigates the effect of ultrasonic vibration applied in the cutting speed direction on surface quality during face turning of C45 steel. The experiments were performed using an ultrasonic generator operating at a frequency of 20 kHz with an amplitude of approximately 10 µm. The cutting parameters used in the experiments included spindle speeds of 700, 1100, and 1300 rpm, feed rates of 0.1 and 0.15 mm/rev, while the depth of cut was fixed at 0.2 mm. Surface quality was evaluated based on the roughness parameters R_a and R_z, as well as surface topography was observed using a Keyence VHX-7000 digital microscope. The results show that ultrasonic-assisted face turning (UAFT) significantly improves surface finish, particularly in the central region of the workpiece where the cutting speed is lower and built-up edge (BUE) formation is more likely. The lowest R_a value recorded was 0.91 µm, representing a 71% reduction compared to conventional turning (CT). Furthermore, at the highest spindle speed (1300 rpm), the standard deviations of both R_a and R_z were minimal, indicating improved surface consistency due to the suppression of BUE by ultrasonic vibration. Topographical observations further confirmed that UAFT generated regular and periodic surface patterns, in contrast to the irregular textures observed in CT. Full article

During the dry machining of 6061 aluminum alloy, cemented carbide tools often suffer from severe wear and built-up edge (BUE) formation, which significantly shortens tool life. Inspired by the non-smooth surface structure of dung beetles, this study proposes an elliptical dimple–groove composite bionic micro-texture, applied to the rake face of cemented carbide tools to enhance their cutting performance. Four types of tools with different surface textures were designed: non-textured (NT), single-groove texture (PT), circular dimple–groove composite texture (AKGC), and elliptical dimple–groove composite texture (TYGC). The cutting performance of these tools was analyzed through three-dimensional finite element simulations using the Deform-3D (version 11.0, Scientific Forming Technologies Corporation, Columbus, OH, USA) software program. The results showed that, compared to the NT tool, the TYGC tool exhibited the best performance, with a reduction in the main cutting force of approximately 30%, decreased tool wear, and significantly improved chip-breaking behavior. Based on the simulation results, a response surface model was constructed to optimize key texture parameters, and the optimal texture configuration was obtained. In addition, a theoretical model was developed to reveal the mechanism by which the micro-texture reduces interfacial friction and temperature rises by shortening the effective contact length. To verify the accuracy of the simulation and theoretical analysis, cutting experiments were further conducted. The experimental results were consistent with the simulation trends, and the TYGC tool demonstrated superior performance in terms of cutting force reduction, smaller adhesion area, and more stable cutting behavior, validating both the simulation model and the proposed texture design. This study provides a theoretical foundation for the structural optimization of bionic micro-textured cutting tools and offers an in-depth exploration of their friction-reducing and wear-resistant mechanisms, showing promising potential for practical engineering applications. Full article

Background/Objectives: Aneurysmal bone cysts (ABCs) are rare bone tumors that can occur in the skull, leading to extensive bone destruction and compression of surrounding tissues. Due to the rarity of these lesions, there are limited data available in the literature, which primarily consists of case reports. We aimed to collect and analyze the available data to summarize the current state of knowledge on this rare pathology, while also conducting a statistical analysis to identify potential risk factors and management strategies. Methods: A review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, covering studies published from January 1950 to December 2023. A total of 60 articles and 74 case reports were included. Results: The mean age at diagnosis was 14.8 ± 12.5 years, with slightly higher male gender predominance. Regarding the different skull bones, a statistically significant higher growth trend of ABCs was found at the parietal bone in the male population (p = 0.025). At the occipital bone, a significant correlation was observed with the age of incidence for symptomatic lesions (p = 0.007) and development from fibrous dysplasia (p = 0.019). Secondary lesions showed a higher frequency of complications within the first months post-surgery (p = 0.041). Conclusions: No significant correlation was found between ABCs and fibrous dysplasia (FD) or head trauma. Male patients with FD showed a higher tendency to develop an aneurysmal cyst at the occipital bone at an older age and a higher tendency for growth in ABCs at the parietal bone. However, to date, no molecular or genetic correlation with male hormones has been reported in the literature. Surgery remains the only effective treatment, but complications should be carefully considered, particularly in patients with pre-existing pathological conditions. Full article

Investigating failure mechanisms in cutting tools used in advanced industries like biomedical and aerospace, which operate under extreme mechanical and chemical conditions, is essential to prevent failures, optimize performance, and minimize financial losses. The diamond-turning process, operating at micrometer-length scales, forms a tightly bonded built-up edge (BUE). The tribochemical interactions between a single-crystal diamond and its deformed chip induce inter-diffusion and contact, rapidly degrading the cutting edge upon BUE fracture. These effects intensify at higher deformation speeds, contributing to the observed rapid wear of diamond tools during d-shell-rich metal machining in industrial settings. In this study, these interactions were studied with niobium (Nb) as the transition metal. Tribochemical effects were observed at low deformation speeds (quasistatic; <1 mm/s), where thermal effects were negligible under in situ conditions inside the FEI /SEM vacuum chamber room. The configuration of the interface region of diamond and transition metals was characterized and analyzed using focused ion beam (FIB) milling and subsequently characterized through transmission electron microscopy (TEM). The corresponding inter-diffusion was examined by elucidating the phase evolution, element concentration profiles, and microstructure evolution via high-resolution TEM/Images equipped with an TEM/EDS system for elemental characterization. Full article

Background and Objectives: Robotic-assisted surgery (RS) has progressively emerged as a promising technology in modern thoracolumbar spinal surgery, offering the potential to enhance accuracy and improve clinical outcomes. To date, the benefits of robot-assisted techniques in thoracolumbar spinal surgery remain controversial. The objective of this study was to assess the efficacy and safety of RS compared to fluoroscopy-assisted surgery (FS) in spinal fusion procedures. Materials and Methods: In accordance with the PRISMA guidelines, a systematic review and meta-analysis was conducted, using REVMAN V5.3 software. The review protocol was registered in the Prospective Register of Systematic Reviews (PROSPERO) website with the following registration number: CRD42024567193. Results: Eighteen studies were included in the meta-analysis with a total of 1566 patients examined. The results demonstrated a worse accuracy in FS in cases with major violations of the peduncular cortex (D–E grades, according to Gertzbein’s classification) [(odds ratio (OR) 0.47, 95%-CI 0.28 to 0.80, I² 0%]. In addition, a lower complication rate was shown in the RS group compared to the FS group, specifically regarding the need for surgical revision due to screw mispositioning (OR 0.28-CI 0.17 to 0.48, I² 98%). Conclusions: Advantages of robot-assisted techniques were demonstrated in terms of postoperative complications, revision surgery rates, and the accuracy of screw placement. While RS represents a valuable and promising technological advancement in thoracolumbar spinal surgery, future studies are needed to further explore its advantages in thoracolumbar spinal surgery and to identify which spinal surgical approach has greater advantages when using the robot. Full article

Introduction: Hereditary transthyretin amyloidosis (ATTRv) is a severe, multisystemic, autosomal dominant disease with variable penetrance caused by mutations in the TTR gene generating protein misfolding and accumulation of amyloid fibrils. The diagnosis is usually challenging because ATTRv may initially manifest with nonspecific multisystemic symptoms. Conversely, an early diagnosis is needed to start timely appropriate therapy. Hence, screening models have been proposed to improve ATTRv diagnosis. In this study, we propose a genetic screening model based on predefined “red flags” followed by “cascading screening” on first-degree relatives of patients who tested positive. Materials and methods: After obtaining written informed consent, genetic testing on salivary swabs was performed in individuals who met at least two major red flags for ATTRv (age > 65 years old, progressive sensory or sensorimotor neuropathy not responsive to steroids or immunomodulant therapies, recent and unexplained weight loss associated with gastrointestinal signs and symptoms, diagnosis of cardiac amyloidosis, bilateral or relapsing carpal tunnel syndrome, unexplained autonomic dysfunction) or one major flag and two minor flags (family history of neuropathy, ambulation disorders or cardiopathy, sudden cardiac death, a bedridden, wheelchaired patient without specific diagnosis excluding upper motor neuron diseases, infections, juvenile cardiac disease, ocular disorders, lumbar spine stenosis, biceps tendon rupture). Results: In the first screening phase, 29 suspected cases (individuals meeting at least two major red flags or one major red flag and two minor red flags) underwent genetic testing. One patient (3.5%) was diagnosed with hereditary transthyretin amyloidosis with polyneuropathy (ATTRv-PN), carrying the Phe64Leu mutation. Then, cascade screening allowed for early recognition of two additional individuals (two pre-symptomatic carriers) among two first-degree relatives (100%). The identified patient was a 72-year-old man who had a family history of both cardiopathy, neuropathy, and a diagnosis of juvenile cardiac disease and progressive sensorimotor neuropathy unresponsive to steroids or immunomodulant therapies. Conclusions: ATTRv is a progressive and often fatal disease that should be promptly diagnosed and treated to stop progression and reduce mortality. Systematic screening for ATTRv yielded increased recognition of the disease in our neurological clinic. A focused approach for the screening of ATTRv-PN could lead to an earlier diagnosis and identification of asymptomatic carriers, enabling timely intervention through close clinical monitoring and early treatment initiation at symptom onset. Full article

Background:Becium grandiflorum is a fragrant perennial shrub of the Lamiaceae family. Objectives: The current study aimed to explore the cytotoxic potential of the n-hexane fraction from Becium grandiflorum aerial parts and, further, isolate its major diterpene and conduct in vitro and in vivo anticancer activities along with its molecular mechanism and synergy with doxorubicin. Methods: The hydroalcoholic extract of Becium grandiflorum aerial parts was fractionated, and the n-hexane fraction was analyzed via GC-MS. The major isolated diterpene, 18-epoxy-pimara-8(14),15-diene (epoxy-pimaradiene), was quantified using UPLC-PDA. Cytotoxicity assays were conducted on HCT-116, MCF-7, MDA-MB-231, and HepG2 cell lines. The synergistic effect with doxorubicin was tested on HepG2 cells. In vivo anticancer activity was evaluated using the Ehrlich ascites carcinoma model, and molecular docking analyzed Bax-Bcl2 interactions. Results: The n-hexane fraction contained 21 compounds, mainly oxygenated diterpenes, and the major isolated compound was epoxy-pimaradiene, with a quantity of 0.3027 mg/mg. N-Hexane fraction and epoxy-pimaradiene exhibited strong cytotoxicity against HepG2 cells, induced apoptosis, and G2/M arrest. The combination of epoxy-pimaradiene with doxorubicin lowered the IC₅₀ of doxorubicin from 4 µM to 1.78 µM. In vivo, both reduced tumor growth and increased necrotic tumor areas. Molecular docking revealed disruption of Bax-Bcl2. Conclusions: The findings suggest that B. grandiflorum and its major diterpene, epoxy-pimaradiene, exhibit potent anticancer activity, particularly against liver cancer cells. Epoxy-pimaradiene enhances doxorubicin’s efficacy, induces apoptosis, and inhibits tumor progression. Further studies are needed to explore their therapeutic potential. Full article

Rapid urbanization and environmental challenges necessitate innovative construction solutions in Egypt. This study presents a 6D Green Building Information Modeling (BIM) framework designed to enhance sustainability, reduce costs, and optimize construction processes. Integrating energy consumption, carbon footprint, and lifecycle performance metrics, the framework addresses critical gaps in Egypt’s construction sector, including limited technical expertise, high costs, and regulatory challenges. A mixed-methods approach was employed, combining global case study analysis, 3D modeling using Autodesk Revit, energy simulations with Autodesk Insight, and project scheduling through Primavera P6. Expert interviews with industry professionals further refined and validated the framework, ensuring its practicality and adaptability to Egypt’s unique socio-economic context. Key findings highlight the framework’s ability to reduce project costs through accurate 3D models, improve scheduling efficiency with 4D and 5D simulations, and enhance sustainability with 6D analyses of energy, water, and photovoltaic systems. The framework not only supports Egypt Vision 2030’s sustainability goals but also provides a clear, step-by-step implementation process using widely adopted tools. This research contributes a comprehensive, scalable model for sustainable construction, offering practical solutions to industry stakeholders. Its adaptable nature makes it relevant for other developing countries facing similar challenges, positioning BIM as a transformative tool for achieving greener, more efficient construction practices. Full article

Ethyl 3-formyl-1H-indol-2-carboxylate (FIC) and 2-(4-methoxyphenyl)-2,4-dihydropyrrolo [3,4-b]indol-3-ol (MPI) were synthesized as indole derivatives. The chemical structures of FIC and MPI were established through analytical and spectroscopic techniques. The inhibitory impacts of FIC and MPI on mild steel (MS) in an acidic environment (0.5 M H₂SO₄) were investigated by employing methodologies including open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP). As the studied indole derivatives adsorbed on the surface of MS, they created a barrier to mass and charge movement, shielding the MS from dangerous ions. It was observed that the inhibitory efficiency (%EF) values increased with the molar concentration of indole derivatives (FIC and MPI). At all concentrations, the two indole derivatives being studied, FIC and MPI, had high efficiency values. The highest efficiencies at 90 ppm were 81.2% with MPI and 76.2% with FIC. The polarization curves also clearly showed that MPI and FIC function as mixed-type inhibitors. Additionally, this study used density functional theory (DFT) and molecular dynamics (MD) simulations to investigate how well the two indole derivatives prevented mild steel corrosion. Full article

Background/Objectives: Hyperlipidemia is a silent threat lurking in the bloodstream of millions worldwide. The nano-based platform has emerged as a promising drug delivery technology. Repaglinide, an anti-diabetic drug, was investigated recently as an antihyperlipidemic candidate that could supersede the available antihyperlipidemic drugs. Our goal was to optimize albumin-based nanoparticles loaded with Repaglinide for parenteral delivery and conduct in silico and in vivo studies to explore the efficacy of Repaglinide for the management of hyperlipidemia along with its anti-diabetic effect. Methods: The impact of three independent factors, the albumin%, acetone volume, and glutaraldehyde/albumin, on the particle size, zeta potential, and entrapment efficiency was investigated. Results: The optimized formulation was spherical, homogenous of an average diameter (~181.86 nm) with a narrow size distribution, a zeta potential of −24.26 mV, and 76.37% as the EE%. The in vitro release of Repaglinide from nanoparticles showed a sustained release pattern for 168 h, with an initial burst release after 24 h, and was fitted to the Fickian diffusion mechanism. A molecular docking simulation showed a strong affinity to several protein targets, and the results were very promising, where Repaglinide gave a score of −7.70 Kcal/mol compared to Mevastatin (−6.71 Kcal/mol) and Atorvastatin (−8.36 Kcal/mol). On conducting in vivo studies on animal models, the optimized formula recorded a statistically significant decrease in the serum levels of total cholesterol, triglyceride, and low-density lipoproteins, with an increased high-density lipoprotein. Conclusions: This study suggested albumin nanoparticles as potential nanocarriers for the parenteral delivery of Repaglinide to ameliorate its antihyperlipidemic benefits, especially in diabetic patients. Full article

A novel self-heating technique is proposed to clear snow from photovoltaic panels as a solution to the issue of winter snow accumulation in photovoltaic (PV) power plants. This approach aims to address the shortcomings of existing methods. It reduces PV cell wear, resource loss, and safety risks, without the need for additional devices. A self-heating current is applied to the solar panel to melt the snow covering its surface, which is then allowed to slide off the panel due to gravity. The proposed system consists of a bidirectional DC-DC converter, which removes the snow cover by heating the solar PV modules using electricity from the grid or electric vehicle (EV) batteries. It also charges the EV battery pack and/or supplies the DC bus when no EV is plugged into the charging station. For each mode of operation, a current-controlled system was implemented using a PI controller and a model predictive controller (MPC). The MPC approach achieved a faster rise time, shorter settling time, very low current ripples, and high stability for the proposed system. Specifically, the settling time decreased from 9 ms and 155 ms when using the PI controller at 20 µs and 35 µs with the MPC controller for both the buck and boost modes, respectively. Full article

Tool selection is relevant because a wide variety of materials exhibit different machinability behaviors. Tool life during manufacturing is commonly associated with productivity. Insert developers have been using coatings on cutting tools to enhance their performance, with chemical vapor deposition (CVD) and physical vapor deposition (PVD) being the two most used techniques. This study analyzed the cutting tool wear mechanism by machining AISI D2 steel using two different inserts of TiAlN/TiN PVD and TiCN/Al₂O₃ CVD as layers deposited on a carbide substrate. The two inserts were tested at three different cutting speeds, namely, low, medium, and high; these values were below the data suggested by the supplier catalog. The flank wear and rake face were analyzed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectrometry (EDX). The adhesion material, edge deformation, and abrasion were the main wear mechanisms before catastrophic damage occurred at the three different cutting speeds in the PVD cutting tool. Nevertheless, increasing the cutting speed reduced the tool life from 84% to 61% at high values compared to the medium values of PVD and CVD, respectively, where the medium value resulted in a balance between the material removal rate and tool life. The wear mechanism of the CVD tool was BUE and chipping; nevertheless, its craters were larger than those of the PVD. Compared to those configured for PVD, the CVD insert demonstrated the ability to machine D2 steel at twice the cutting speed with a workpiece surface roughness of 0.3 µm, in contrast to a variation of 0.6 to 0.15 µm with the PVD tool. Full article

Eco-friendly iron and manganese oxide nanoparticles (Fe₂O₃ and Mn₂O₃) were synthesized and integrated into graphene sheets to form uniform composites. These composites were then embedded in polyvinyl alcohol (PVA) fibers using electrospinning. Comprehensive characterization of the composites and the final composite fibers was conducted using XRD, FE-SEM, and FTIR to analyze their structural complexity and morphological differences. The antibacterial efficacy of the resulting PVA nanofibers was evaluated against Escherichia coli, which is a common pathogen in hospital environments. The results show a significant bactericidal effect against these bacteria, which highlights their potential in medical applications, such as functional bandages and wound dressings. This study paves the way for potential commercial applications of these nanofibers in healthcare settings. Full article