Search Results (1,814)

Direction of arrival (DOA) estimation plays a critical role in remote sensing, where it aids in identifying and tracking multiple targets across complex environments, from atmospheric monitoring to resource mapping. Leveraging difference covariance array (DCA) for DOA estimation has become prevalent, particularly with sparse arrays capable of resolving more targets than the number of sensors. This paper proposes a new hole-free sparse array configuration for remote sensing applications to achieve improved DOA estimation performance using DCA. By symmetrically placing a minimum redundancy array (MRA) and its complementary MRA on both sides of a sparse uniform linear array (ULA), this configuration maximizes degrees of freedom (DOFs) and minimizes mutual coupling effects. Expressions for calculating sensor positions and optimal element allocation methods to maximize DOFs are derived. Simulation experiments in various scenarios have shown the advantages of the proposed array in DOA estimation, including a strong ability to estimate multi-targets, high angular resolution, low estimation error, and strong robustness to mutual coupling. Full article

Background: The majority of patients with bladder cancer suffer from tumour recurrence. Identifying prognostic factors for tumour recurrence is crucial for treatment and follow-up in affected patients. The study aimed to assess the impact of somatic mutations in bladder cancer on patient outcomes and tumour recurrence. Methods: The study group comprised 46 patients with urothelial bladder cancers referred for transurethral resection of the tumour. A molecular study on tumour-derived DNA was performed using next-generation sequencing. Somatic mutations were screened in 50 genes involved in carcinogenesis. Results: We identified 81 variants in 23 genes, including 54 pathogenic mutations, 18 likely pathogenic variants, and 9 variants of unknown significance. The most frequently mutated genes were FGFR3, PIK3CA, and TP53 in 52%, 35%, and 24% of tumours, respectively. The average tumour-free survival was significantly longer in cases with mutations in the PIK3CA gene (p = 0.02), and mutations in the PIK3CA gene were associated with a decreased risk of tumour recurrence (Hazard Ratio = 0.26; 95% CI: 0.11–0.62; p = 0.018). Conclusions: The PIK3CA gene was shown to be a predictive marker of a low risk of bladder tumour recurrence. Molecular screening of bladder cancers supported predictive biomarkers of tumour recurrence and showed that tumour-free survival is molecularly determined. Full article

Calcium and barium carbonates were synthesized via biologically induced mineralization using Bacillus subtilis. The biogenic materials were characterized by using infrared and Raman spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and powder X-ray diffraction. These biogenic carbonates were then tested as basic heterogenous catalysts for the solvent-free Knoevenagel reaction between 5-HMF derivatives and active methylene compounds, producing 3-(furan-2-yl)acrylonitrile derivatives in 71–87% yields. Optimal catalytic performance was achieved with a 50:50 Ca:Ba ratio, attributed to the synergistic interaction between baritocalcite and vaterite, which enhances the availability of active basic sites and surface interactions. This method offers operational simplicity, reduced reaction times, good yields, excellent (E)-selectivity, and minimal catalyst loading. Full article

Background: Type 2 diabetes has become a significant global health challenge. Numerous drugs have been developed to treat the condition, either as standalone therapies or in combination when glycemic control cannot be achieved with a single medication. As existing treatments often come with limitations, there is an increasing focus on creating novel therapeutic agents that offer greater efficacy and fewer side effects to better address this widespread issue. Methods: The methylene derivatives 3a,b were coupled with phenyl/ethyl isothiocyanate in the basic medium, and dimethyl sulfate was subsequently added. Further, 5a–d were reacted with the quinoline/naphthalene hydrazides 6a,b. The target compounds 7a–g were subjected to the in vitro enzyme inhibition studies on α-glucosidase, α-amylase, and aldose reductase. Results: 7g exerted remarkable inhibitory effects on α-glycosidase [Inhibitory Concentration (IC₅₀): 20.23 ± 1.10 µg/mL] and α-amylase (17.15 ± 0.30 µg/mL), outperforming acarbose (28.12 ± 0.20 µg/mL for α-glycosidase and 25.42 ± 0.10 µg/mL for α-amylase), and exhibited a strong inhibition action on aldose reductase (12.15 ± 0.24 µg/mL), surpassing quercetin (15.45 ± 0.32 µg/mL) and the other tested compounds. In a computational study, 7g demonstrated promising binding affinities (−8.80, −8.91 kcal/mol) with α-glycosidase and α-amylase, compared to acarbose (−10.87, −10.38 kcal/mol) for α-glycosidase and α-amylase. Additionally, 7g had strong binding with aldose reductase (−9.20 kcal/mol) in comparison to quercetin (−9.95 kcal/mol). Molecular dynamics (MDs) simulations demonstrated that 7g remained stable over a 100 ns simulation period, and the binding free energy estimates remained consistent throughout this time. Conclusions: We reported the modification of quinoline and naphthalene rings to hydrazineylidene–propenamides 7a–g using various synthetic approaches. 7g emerged as a leading candidate, exhibiting greater inhibition of α-glycosidase, α-amylase, and aldose reductase. These findings underscore their potential as essential molecules for the development of innovative antidiabetic treatments. Full article

Cellular heterogeneity, an inherent feature of biological systems, plays a critical role in processes such as development, immune response, and disease progression. Human mesenchymal stem cells (hMSCs) exemplify this heterogeneity due to their multi-lineage differentiation potential. However, their inherent variability complicates clinical use, and there is no universally accepted method for detecting and quantifying cell population heterogeneity. Dielectrophoresis (DEP) has emerged as a powerful electrokinetic technique for characterizing and manipulating cells based on their dielectric properties, offering label-free analysis capabilities. Quantitative information from the DEP spectrum, such as transient slope, measure cells’ transition between negative and positive DEP behaviors. In this study, we employed DEP to estimate transient slope of various cell populations, including relatively homogeneous HEK-293 cells, heterogeneous hMSCs, and cancer cells (PC3 and DU145). Our analysis encompassed hMSCs derived from bone marrow, adipose, and umbilical cord tissue, to capture tissue-specific heterogeneity. Transient slope was assessed using two methods, involving linear trendline fitting to different low-frequency regions of the DEP spectrum. We found that transient slope serves as a reliable indicator of cell population heterogeneity, with more heterogeneous populations exhibiting lower transient slopes and higher standard deviations. Validation using cell morphology, size, and stemness further supported the utility of transient slope as a heterogeneity metric. This label-free approach holds promise for advancing cell sorting, biomanufacturing, and personalized medicine. Full article

Cannabis sativa L. cv. ‘Cheungsam’ is an industrial hemp plant of Republic of Korea origin, primarily cultivated for fiber and seed production. In vitro seed germination and tissue culture are valuable tools for developing various biotechnological techniques. In the present study, we aimed to develop a tissue culture process for hemp plants using Cheungsam as a model plant and examine the secondary metabolites produced from its callus. We also developed a method to prepare pathogen-free seedlings from field-derived seeds using hydrogen peroxide (H₂O₂) solution as a liquid germination medium. Treating seedlings with removed seed coat in 3% H₂O₂ significantly reduced the contamination rate. Callus formation and de novo organogenesis of shoots and roots from callus were successfully achieved using cotyledon and leaf tissues prepared from the pathogen-free seedlings. The most effective in vitro regeneration results were obtained using the Murashige and Skoog (MS) medium supplemented with certain targeted growth regulators. An optimal combination of 0.5 mg/L thidiazuron (TDZ) and 1.0 mg/L 1-naphthalene acetic acid proved highly effective for callus induction. The addition of 0.5 mg/L TDZ in the MS medium significantly stimulated shoot proliferation, while robust root development was best supported by MS medium supplemented with 2.5 mg/L indole-3-butyric acid for both cotyledon and leaf explants. Finally, gas chromatography–mass spectrometry (GC–MS) analysis of ethanol extract from Cheungsam leaf callus revealed the presence of different secondary metabolites, including 9-octadecenamide, methyl salicylate, dodecane, tetradecane, and phenol, 2,4-bis-(1,1-dimethylethyl). This study provides a comprehensive de novo regeneration protocol for Cheungsam plants and insight into the secondary metabolite profiles of its callus. Full article

Rice husk, a byproduct of rice production, poses significant environmental challenges due to disposal issues, while the emission of volatile organic compounds into the atmosphere further exacerbates these concerns. This study addresses both problems by exploring the potential of texturally enhanced SiO₂, derived from Uruguayan rice husk, as a catalytic support for manganese oxides in the combustion of volatile organic compounds. SiO₂ was synthesized from rice husk ash using a sustainable, acid-free pretreatment method, yielding a notably high silica purity of 96.5%—a level comparable to or exceeding previously reported values, highlighting the high silica quality inherent in Uruguayan rice husk. The catalytic activity was evaluated using acetone as a model volatile organic compound, achieving up to 90% conversion with 30 wt.% manganese oxide at 300 °C, with CO₂ as the primary product. Furthermore, a 24 h stability test demonstrated consistent performance, maintaining a conversion rate of around 95.6 ± 2.5%. These findings suggest that high-purity SiO₂ derived from Uruguayan rice husk, with its sustainability benefits, offers an effective solution for acetone removal when supporting an active phase such as manganese oxides, addressing both rice husk disposal and volatile organic compound emissions. Full article

As an important component of the automatic hydraulic quick coupling device (AHQCD) on rescue vehicles, the hydraulic quick couplings (HQCs) are used to rapidly dock hydraulic lines and transport fluid while changing and operating hydraulic working tools. However, during tool operation at rescue sites, pressure pulsations at multiple frequencies in the hydraulic lines can coincide with the natural frequencies of the HQCs, potentially causing resonance that severely affects the stability of fluid conveying and damages the connection of hydraulic lines accidentally. To investigate the natural frequencies of the HQCs with upstream and downstream lines, the characteristics of fluid–structure interaction were considered between the poppets and the fluid in this study, and an equivalent stiffness model of the fluid domain was derived based on the fluid compressibility. A dynamic model, along with 6-DOF equations for the system, was established, and the natural frequencies and mode vectors were determined by free vibration analysis. In addition, the effects of working pressure, air content, and stiffness of the springs on the natural frequency of the HQC system were analyzed. The results show the natural frequency increases with a higher working pressure and lower air content, while the effect of spring stiffness on natural frequencies varies with different modes. Furthermore, the proposed model is validated by experimental pressure signals, showing good agreement, with an average error of 2.7% for the first-order natural frequency. This paper presents a theoretical method for improving the stability of fluid transport when operating various hydraulic tools under complex rescue conditions. Full article

Despite prevention strategies, cervical cancer remains a significant public health issue. Human papillomavirus plays a critical role in its development, and early detection is vital to improve patient outcomes. The incidence of cervical cancer is projected to rise, necessitating better diagnostic tools. Traditional screening methods like the cytological examination and human papillomavirus testing have limitations in sensitivity and reproducibility. Liquid-based cytology offers some improvements, but the need for more reliable and sensitive techniques persists, particularly for detecting precancerous lesions. Liquid biopsy is a non-invasive method that analyzes cancer-derived products in biofluids like blood, offering potential for real-time monitoring of tumor progression, metastasis, and treatment response. It can be based on detection of circulating tumor cells (CTCs), circulating free DNA (cfDNA), and microRNAs (miRNAs). This review particularly underlines the potential of microRNAs, which are transported by extracellular vesicles. Overall, this article underscores the importance of continued research into non-invasive diagnostic methods like liquid biopsy to enhance cervical cancer screening and treatment monitoring. Full article

Reverberation and background noise are common and unavoidable real-world phenomena that hinder automatic speaker recognition systems, particularly because these systems are typically trained on noise-free data. Most models rely on fixed audio feature sets. To evaluate the dependency of features on reverberation and noise, this study proposes augmenting the commonly used mel-frequency cepstral coefficients (MFCCs) with relative spectral (RASTA) features. The performance of these features was assessed using noisy data generated by applying reverberation and pink noise to the DEMoS dataset, which includes 56 speakers. Verification models were trained on clean data using MFCCs, RASTA features, or their combination as inputs. They validated on augmented data with progressively increasing noise and reverberation levels. The results indicate that MFCCs struggle to identify the main speaker, while the RASTA method has difficulty with the opposite class. The hybrid feature set, derived from their combination, demonstrates the best overall performance as a compromise between the two. Although the MFCC method is the standard and performs well on clean training data, it shows a significant tendency to misclassify the main speaker in real-world scenarios, which is a critical limitation for modern user-centric verification applications. The hybrid feature set, therefore, proves effective as a balanced solution, optimizing both sensitivity and specificity. Full article

We developed a selective technique to rapidly measure free chlorine, which is the sum of elemental chlorine (Cl₂), hypochlorous acid (HOCl), and hypochlorite (OCl⁻) in water samples via an electrophilic aromatic substitution reaction hyphenated with liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). Sample preparation involved derivatization at 25 °C for 15 min with 3,4,5-trimethoxyphenylacetic acid (TMPAA) in an aqueous solution prior to analysis. Several parameters were evaluated to determine the optimized reaction and for the production of informative MS/MS spectrum of the derivatization product, 2-chloro-3,4,5-trimethoxyphenylacetic acid (Cl-TMPAA). The resulting Cl-TMPAA derivative displayed an informative ESI-MS/MS spectrum characterized by product ions at m/z 232.0142, 200.0245, and 185.0009 from the precursor ion at m/z 259.0379. The linear dynamic range of the method (0.1–10 µg/mL) was fitted to concentration levels relevant to forensic toxicology issues. Compared with other analytical techniques, this newly established LC-MS-based method demonstrated specificity, simplicity, and rapidity. This method enables the detection of free chlorine for forensic investigations in criminal cases. Full article

Background: Mesenchymal stem cells (MSCs) have drawn significant attention for their regenerative potential and therapeutic applicability across a range of conditions, including cardiovascular diseases and age-related frailty. Despite extensive preclinical studies, there remain gaps in understanding the long-term safety and efficacy of MSC therapy in humans. This study aimed to assess the safety of intravenous MSC administration, evaluate the mean major adverse cardiac and cerebrovascular event (MACCE)-free period, and identify potential risk factors for MACCE development in patients receiving MSC therapy for various indications. Methods: A retrospective observational study was conducted on 2504 patients (mean age: 54.09 ± 11.65 years) who received intravenous adipose-derived MSC (AD-MSC) therapy between October 2014 and December 2023 at the Omotesando Helene Clinic, Tokyo, Japan. Patients received MSC doses ranging from 100 million to 2 billion cells, with the majority receiving 1–2 billion cells per treatment. Statistical analyses included multivariate Cox proportional hazards regression and Kaplan–Meier survival analysis to evaluate MACCE risk factors and event-free duration. Results: Over the follow-up period, the MACCE rate was exceptionally low at 0.2%. Multivariate analysis identified age as a significant risk factor for MACCE (hazard ratio: 1.127; 95% CI: 1.0418–1.219; p = 0.0029), while sex and MSC dose showed no significant association. Minor adverse events occurred in 0.8% of patients, with no severe adverse events reported. The study found MSC therapy to be safe, with a low adverse event rate and minimal risk of MACCE. Conclusions: This study demonstrates the safety of intravenous MSC therapy in a large cohort of patients, with a low incidence of MACCE and minimal adverse effects. Age was the only significant predictor of MACCE risk. Further prospective randomized studies are needed to validate these findings and explore the potential of MSC therapy in reducing MACCE risk and improving clinical outcomes across diverse indications. Full article

Background. Minimally invasive distal gastrectomy (MIDG) has been shown to be associated with improved short-term outcomes compared to open distal gastrectomy (ODG) in patients with locally advanced gastric cancer (LAGC). The impact of MIDG on long-term patient survival remains debated. Aim was to compare the MIDG vs. ODG effect on long-term survival. Methods. Systematic review and trial sequential analysis (TSA) of randomized controlled trials (RCTs). Web of Science, Scopus, MEDLINE, the Cochrane Central Library, and ClinicalTrials.gov were queried. Hazard ratio (HR) and 95% confidence intervals (CI) were used as pooled effect size measures. Five-year overall (OS) and disease-free survival (DFS) were primary outcomes. Results. Five RCTs were included (2835 patients). Overall, 1421 (50.1%) patients underwent MIDG and 1414 (49.9%) ODG. The ages ranged from 48 to 70 years and 63.4% were males. The pooled 5-year OS (HR = 0.86; 95% CI 0.70–1.04; I² = 0.0%) and 5-year DFS (HR = 1.03; 95% CI 0.87–1.23; I² = 0.0%) were similar for MIDG vs. ODG. The TSA shows a cumulative z-curve without crossing the monitoring boundaries line (Z = 1.96), thus suggesting not conclusive 5-year OS and DFS results because the total information size was not sufficient. Conclusions. MIDG and ODG seem to have equivalent 5-year OS and DFS in patients with LAGC. However, the cumulative evidence derived from the TSA showed that the actual information size is not sufficient to provide conclusive data. Full article

In this study, homoisoflavone methylophiopogonanone A (MOA) was investigated for its inhibitory effect on ferroptosis of H9c2 cells using a set of cellular assays, such as BODIPY-probed and H₂DCFDA-probed flow cytometry analyses, cell counting kit-8 analysis (CCK-8), and lactate dehydrogenase (LDH) release analysis. All these cellular assays adopted Fer-1 as the positive control. Subsequently, MOA and Fer-1 were subjected to two antioxidant assays, i.e., 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide radical (PTIO^•)-scavenging and 2,2′-azinobis(3-ethylbenzo-thiazoline-6-sulfonic acid radical (ABTS^•+)-scavenging. Finally, MOA, along with Fer-1, were systematically analyzed for molecular docking and dynamics simulations using a set of software tools. The experimental results revealed that MOA could inhibit ferroptosis of H9c2 cells but did not effectively scavenge PTIO^• and ABTS^•+ free radicals. Two molecular simulation methods or algorithms suggested that MOA possessed similar binding affinity and binding free energy (∆G_bind) to Fer-1. Visual analyses indicated various hydrophobic interactions between MOA and one of the seven enzymes, including superoxide dismutase (SOD), dihydroorotate dehydrogenase (DHODH), ferroportin1 (FPN), ferroptosis suppressor protein 1 (FSP1), glutathione peroxidase 4 (GPX4), nicotinamide adenine dinucleotide phosphate (NADPH), and solute carrier family 7 member 11 (SLC7A11). Based on these experimental and molecular simulation results, it is concluded that MOA, a homoisoflavonoid with meta-di-OHs, can inhibit ferroptosis in H9c2 cells. Its inhibitory effect is mainly attributed to the regulation of enzymes rather than direct free radical scavenging. The regulation of enzymes primarily depends on hydrophobic interactions rather than H-bond formation. During the process, flexibility around position 9 allows MOA to adjust to the enzyme binding site. All these findings provide foundational information for developing MOA and its derivatives as potential drugs for myocardial diseases. Full article

Background: Medical devices used for functional or esthetic purposes improve health and quality of life; however, they are not risk-free. Anaplastic large-cell lymphoma (ALCL), associated with breast implants, is a well-known and recognized distinct lymphoma entity. More recently, additional lymphomas have been reported in relation to prosthesis other than breast implants, as these allow the pericyte to develop into a clone that undergoes a maturation process, progressing toward full malignancy. Methods: We performed a systematic review with a descriptive analysis of data extracted from primary studies following PRISMA guidelines, including the search string “(IMPLANT* OR PROSTHES*) AND LYMPHOM*” in the PubMed, Scopus, Embase, and Google-Scholar databases. Data such as patient sex, age, implant site, prosthesis material, and lymphoma type were analyzed. Statistical methods, including Student’s t-test and Fisher’s exact test, were employed to compare lymphoma characteristics, with significance set at a p-value < 0.05. Results: From a total of 5992 studies, we obtained 43 case reports and series on a total of 52 patients diagnosed with prosthesis-associated lymphomas. The majority of implant-related lymphoma cases (85%) were of the B-cell type, mostly fibrin-associated large B-cell lymphoma (LBCL). This lymphoma type was more associated with biological (non-human-derived biological tissue), metallic, and synthetic implants (synthesized from non-organic components) (p-value = 0.007). Patients with ALCL had equal frequencies of metal and silicone prostheses (37.5%, 3 cases each), followed by synthetic prostheses (25%, 2 cases). ALCL cases were most common at skeletal (50%) and muscular-cutaneous sites (25%), whereas B-cell lymphomas were predominantly found in cardiovascular implants (50%), followed by skeletal (27%) and muscular-cutaneous (21%) sites. Death attributed to lymphoma took place in 67% of the cases, mostly LBCL occurring in cardiovascular sites. Conclusions: Because the included studies were limited to case reports and series, a potential non-causal link might have been documented between different implant materials, implant sites and lymphoma types. This underscores the importance of further comprehensive research and monitoring of non-breast implants. Full article