Search Results (2,285)

N,N-Ditosyl-2-aminodiphenylamine was prepared by the tosylation of 2-aminodiphenylamine with tosylchloride in dichloromethane. Unwanted isomers owing to the tosylation of the diarylamine were not formed. This compound was fully characterized by IR, UV/Vis, NMR, m/z, and mp, including an X-Ray single crystal structure determination. It was fragmented in an Atmospheric Solids Analysis Probe (ASAP) mass spectrometer showing a series of fragments down to phenazine. Full article

Background: Repeat induced abortion (defined as ≥two lifetime procedures) is becoming more common worldwide, yet its independent influence on women’s psychological health remains contested, particularly in settings where access to modern contraception is restricted. Objectives: This review sought to quantify the burden of depression, anxiety, stress, and generic quality of life (QoL) among women with repeat abortions and to determine how barriers to contraceptive access alter those outcomes. Methods: Following the preregistered PRISMA-2020 protocol, PubMed, Embase and Scopus were searched from inception to 31 June 2025. Results: Eight eligible studies comprising approximately 262,000 participants (individual sample sizes up to 79,609) revealed wide variation in psychological morbidity. Prevalence of clinically significant symptoms ranged from 5.5% to 24.8% for depression, 8.3% to 31.2% for anxiety, and 18.8% to 27% for perceived stress; frequent mental distress affected 12.3% of women in neutral policy environments but rose to 21.9% under highly restrictive abortion legislation. Having three or more abortions, compared with none or one, increased the odds of depressive symptoms by roughly one-third (pooled OR ≈ 1.37, 95% CI 1.13–1.67). Contextual factors exerted comparable or stronger effects: abortions sought for socioeconomic reasons elevated depression odds by 34%, unwanted disclosure of the abortion episode increased depressive scores by 0.62 standard deviations, and low partner support raised them by 0.67 SD. At the structural level, every standard deviation improvement in a state’s reproductive rights index reduced frequent mental distress odds by 5%, whereas enactment of a near-total legal ban produced an absolute increase of 6.8 percentage points. QoL outcomes were less frequently reported; where measured, denied or heavily delayed abortions were associated with a 0.41-unit decrement on a seven-point life satisfaction scale. Conclusions: Psychological morbidity after abortion clusters where legal hostility, financial hardship, or interpersonal coercion constrain contraceptive autonomy while, in comparison, the mere number of procedures is a weaker predictor. Interventions that integrate stigma-free mental health support with confidential, affordable, and rights-based contraception are essential to protect well-being in women who experience repeat abortions. Full article

Iron detection is of growing importance in the critical minerals sector, where unwanted iron ions are typically removed during the processing of target critical metals. The ideal sensor should utilize inexpensive, scalable materials along with a low-cost, robust, and easy-to-use analysis platform. Here, we demonstrate a simple acid–base synthesis of luminescent iron-responsive carbon dots by reacting ethanolamine, phosphoric acid, and m-phenylenediamine. The carbon dots exhibit selective, iron-specific emission quenching, with the ability to detect part-per-billion levels of iron ions even in 0.1 M HCl. After benchmarking the purified materials using a commercial spectrometer, a “low-cost” process is demonstrated in which carbon dots with minimal purification are coupled with a portable fiber-optic spectrometer for analyzing iron content. Carbon dot-coated paper strips are also evaluated as another convenient platform for iron analysis. Taken together, the sensing material and platforms demonstrated here are well-suited for detecting trace quantities of iron in environmentally relevant conditions, with potential applications in tracking iron removal processes during critical mineral production as one exciting area of interest. Full article

By applying the Non-Perturbative Approach (NPA), the corresponding linear differential equation is obtained. Aimed at organizational investigation, the resulting linear equation is used. Strong agreement between numerical calculations and the precise frequency is demonstrated, and the reliability of the results acquired is established by the correlation with the numerical solution. Additionally, this study explores a new control process to affect the stability and behavior of dynamic motorcycle systems that vibrate nonlinearly. A multiple time-scale method (MTSM) is applied to examine the analytical solution of the nonlinear differential equations describing the aforementioned system. Every instance of resonance was taken out of the second-order approximations. The simultaneous primary and 1:1 internal resonance case ($\mathsf{\Omega }\approx {\omega }_{eq},$${\omega }_2\approx {\omega }_{eq}$) is recorded as the worst resonance case caused while working on the model. We investigated stability with frequency–response equations and bifurcation. Numerical solutions for the system are covered. The effects of the majority of the system parameters were examined. In order to mitigate harmful vibrations, the controller under investigation uses (PD) proportional derivatives with (PPF) positive position feedback as a new control technique. This creates a new active control technique called PDPPF. A comparison between the PD, PPF, and PDPPF controllers demonstrates the effectiveness of the PDPPF controller in reducing amplitude and suppressing vibrations. Unwanted consequences like chaotic dynamics, limit cycles, or loss of stability can result from bifurcation, which is the abrupt qualitative change in a system’s behavior as a parameter. The outcomes showed how effective the suggested controller is at reducing vibrations. According to the findings, bifurcation analysis and a control are crucial for designing vibrating dynamic motorcycle systems for a range of engineering applications. The MATLAB software is utilized to match the analytical and numerical solutions at time–history and frequency–response curves (FRCs) to confirm their comparability. Additionally, case studies and numerical simulations are presented to show how well these strategies work to control bifurcations and guarantee the desired system behaviors. An analytical and numerical solution comparison was prepared. Full article

This study aims to improve the automatic detection of unwanted emails using advanced machine learning and deep learning methods. By reviewing current research over the past five years, a comprehensive combined dataset structure was created containing a total of 81,586 email samples from seven different spam datasets. Class imbalance was addressed through the application of random oversampling and class-weighted loss, and the decision threshold was subsequently tuned for deployment. Among classical machine learning solutions, Random Forest (RF) emerged as the most successful method, while deep learning approaches, such as Transformer-based models like Distilled Bidirectional Encoder Representations from Transformers (DistilBERT) and Robustly Optimized BERT Pretraining Approach (RoBERTa), demonstrated superior performance. The highest test score (99.62%) on a combined static dataset was achieved with a multimodal architecture that combines deep meaningful text representations from DistilBERT with structural text features. Beyond this static performance benchmark, the study investigates the critical challenge of concept drift by performing a temporal analysis on datasets from different eras. The results reveal a significant performance degradation in all models when tested on modern spam, highlighting a critical vulnerability of statically trained systems. Notably, the Transformer-based model demonstrated greater robustness against this temporal decay compared to traditional methods. This study offers not only an effective classification solution but also provides crucial empirical evidence on the necessity of adaptive, continually learning systems for robust spam detection. Full article

For organizations, protecting computer networks has always been a very tough and demanding task. In the current technological era digital resources can now be protected without the need for outdated traditional perimeter-based security techniques. Organizations can use the Zero Trust Network Access (ZTNA) approach to safeguard and filter their vital digital assets for the company’s benefit. This platform uses sophisticated logical authentication to test the system’s ability to authenticate users, and network monitoring is used to look for possible security flaws and system vulnerabilities. By evaluating users’ interactions with the system and their handling of assigned digital resources, multi-factor authentication filters out unwanted access attempts. Three fundamental access control styles are provided by network segmentation, giving administrators the option to manage access in a democratic, strict, or flexible manner (least privilege approach). Full article

The growing accumulation of waste lubricating oil presents serious environmental issues, calling for sustainable management solutions. This research discusses the creation of FeNi/TiO₂ nanocatalysts that were synthesized through an eco-friendly method utilizing grape seed extract (GSE) as a natural reducing agent for the catalytic pyrolysis of waste lubricating oil. The nanocatalyst was produced using the microemulsion technique and refined via Response Surface Methodology (RSM) to optimize its catalytic performance. Pyrolysis was carried out at 400 °C, leading to a significant conversion of waste oil into valuable fuel. The FeNi/TiO₂ nanocatalyst exhibited exceptional capabilities in facilitating the breakdown of heavy hydrocarbons into lighter fuel fractions while reducing unwanted byproducts. GC-MS analysis demonstrated the prevalence of C6–C20 hydrocarbons in the pyrolysis oil, underscoring its potential as a high-quality alternative fuel similar to traditional diesel. This study aids in the progress of environmentally sustainable waste-to-energy technologies, offering a promising pathway for effective fuel production and hazardous waste management. Full article

Aquatic ecosystems are threatened by various anthropogenic activities, including those exacerbated by pesticides leaching from agricultural lands. Although legislation and regulations regarding pesticides aim to eliminate the risk of eutrophication and pollution, only a few studies have examined the impact of these substances on non-target organisms, such as microalgae, which are highly involved in biogeochemical cycles and critical for ecosystem integrity. We studied the effect of the agricultural insecticide Teppeki based on flonicamid, the fungicide Ortiva with azoxystrobin, and the herbicide Basar with (S)-metolachlor on the green microalga Chlorella vulgaris and the cyanobacterium Synechococcus leopoliensis. Ortiva and Basar were more toxic at lower doses than Teppeki, with (S)-metolachlor demonstrating the most instantaneous and potent inhibition. Half maximum effective concentration (EC₅₀) values confirmed the strong inhibitory effect of the herbicide on both strains on days 3 and 8, and highlight the differing temporal responses, especially for Ortiva. This observed pattern of toxicity is consistent with pulse-amplitude-modulated fluorescence measurements of photosystem II, which indicate that both species are more sensitive to (S)-metolachlor and azoxystrobin than to flonicamid. We claim that the side effects of pesticides on non-target organisms must be given more attention. It is well established that herbicides can impair photosynthetic organisms such as microalgae, but pesticides targeting other pests can also cause adverse effects on these communities. Such unwanted side effects are directly related not only to the reduction of biodiversity, but also to human health. Full article

Heat spots caused by standing waves in an inspected object can pose practical challenges in nondestructive inspection using ultrasonic excitation thermography. This study investigates the dominant wave mode excited during inspection and explores methods to suppress heat generation caused by standing waves. Comparison of experimental results and theoretical calculations showed that the waves propagating in plate objects were dominated by the A₀ mode Lamb waves. As a result, the distribution of the heat spots caused by standing waves varied depending on the frequency of the excitation wave and plate thickness. Based on these findings, we propose a suppression method that eliminates unwanted heat spots by superimposing two Lamb waves with a phase difference that is a natural multiple of half the wavelength. Full article

Vibro-thermography is an effective nondestructive testing technique for detecting closed defects like cracks and delaminations through frictional heat generated under ultrasonic excitation. However, its accuracy is often reduced by standing wave patterns that create periodic temperature artifacts in non-defective areas, leading to false positives. To overcome this, we propose an image processing approach using 2D Fourier Transform (2D-FFT) to reduce SW-induced patterns in the frequency domain. This enhances defect visibility by suppressing unwanted heat signatures. The method is evaluated on a cracked PMMA plate and a hollow tube of the same material. Full article

Mitigating multipath interference is one of the biggest challenges in radio positioning. The Supercorrelation™ technology developed via Focal Point Positioning (FPP) suppresses multipath interference by performing long coherent integration while undergoing complex motion to isolate the Line-Of-Sight (LOS) signals from the unwanted multipath interference.This article presents live results with a Supercorrelating Global Navigation Satellite System (S-GNSS) Software-Defined Radio (SDR), demonstrating significantly suppressed multipath to regain position accuracy. Full article

Pediatric hip surgeries are associated with moderate to high levels of pain, which, in severe cases can lead to opioid prescription and use. There is a growing focus on reducing post-operative pain in these patients to decrease the need for opioids, as well as increase early mobilization for recovery. Conventional methods of pain relief using opioids can have unwanted negative impacts on pediatric patients such as respiratory depression, nausea, confusion, and the concerning possibility for the development of dependence. Likewise, traditional methods of anesthesia, like the lumbar epidural block, can have unwanted systemic side effects, such as hypotension, urinary retention, arrhythmias, and spinal abscesses. These complications can lead to longer hospital stays and delayed recovery. This review analyzes the efficacy of a newer regional anesthesia technique, the pericapsular nerve group (PENG) block, in comparison to the lumbar epidural block. This technique utilizes precision-based anesthesia to selectively block the articular branches to the hip joint while avoiding the main trunks of the femoral and obturator nerves. Additionally, with the utilization of high-resolution ultrasound to guide the blocks, providers can increasingly count on proper insertion and predictable anesthetic spread. The result is a motor-sparing blockade that shows promise in allowing earlier mobilization and better functional recovery times after pediatric hip surgeries. Full article

Winter and Spring variations of the fat and fatty acid compositions of discards from six species of the Aegean Sea were investigated to assess the potential suitability for human or aquaculture consumption. European pilchard (Sardina pilchardus), anchovy (Engraulis encrasicolus), curled picarel (Centracanthus cirrus), gilt sardine (Saridenella aurita), horse mackerel (Trachurus mediterraneus) and bogue (Boops boops) were collected from the local fishing wharf during winter and spring. In most species, the specimens caught in spring exhibited elevated fat and n-3 long-chain polyunsaturated fatty acid content, with Sardina pilchardus showing an increase in DHA from 13.59% to 16.06% and Engraulis encrasicolus from 20.36% to 23.41% of the total identified fatty acids. Despite their lower commercial value, the high n-3 LC-PUFA content renders them nutritionally valuable and eligible for use by the aquafeed industry as an alternative to the increasingly costly fish oil. Moreover, in accordance with EU legislation banning discards and mandating the landing of unwanted catches, the valorisation of these species, in line with circular economy principles, could enhance fishers’ income, reduce waste and contribute to the long-term sustainability of marine ecosystems. Full article

Weeds are among the primary factors limiting corn and bean productivity, accounting for up to 30% of yield losses. Although chemical herbicides remain the predominant weed control strategy, their toxicity poses significant risks to human health and the environment. In response, organic agriculture has gained prominence as a more sustainable production system, with an increasing interest in alternative weed management approaches. Plants that produce allelopathic compounds capable of inhibiting the growth of unwanted species have emerged as promising sources of natural bioherbicides. While recent reviews have primarily focused on bioherbicides derived from microorganisms, a notable gap remains regarding the production and application of bioherbicides based on plant extracts. This review addresses this gap by summarizing current knowledge on the use of plant extracts for weed control in corn and bean cultivation. It discusses extraction methods, key plant species and active compounds, target weed species, herbicidal effects, modes of action, and patented technologies. Promising plants include Cuscuta campestris, Cymbopogon citratus, Mentha spp., Eucalyptus spp., and Pinus spp., which are rich in bioactive compounds such as phenolics (i.e., flavonoids), quinones, aldehydes and ketones, lactones, terpenoids (i.e., 8-cineole), and steroids. Plant extract-based bioherbicides show promising potential as sustainable and effective alternatives for weed management in organic agriculture, contributing to reducing the synthetic chemical herbicides, avoiding more resistances of weeds resistance of control, and promoting more environmentally friendly agricultural practices. Full article

In this study, the effects of plasma assistance on the electron beam physical vapour deposition (EB-PVD) process were investigated using an industrial coater (Smart Coater ALD Vacuum Technologies GmbH) equipped with a dual hollow cathode system. This configuration enabled the generation of a plasma environment during the deposition of the ceramic top coat onto a metallic substrate. The objective was to assess how plasma assistance influences the microstructure and thickness distribution of 7% wt. yttria-stabilised zirconia (YSZ) thermal barrier coatings (TBCs). Coatings were deposited with and without plasma assistance to enable a direct comparison. The thickness uniformity and columnar morphology of the 7YSZ top coats were evaluated by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The mechanical properties of the deposited coatings were verified by the scratch test method. The results demonstrate that, in the presence of plasma, columnar grains become more uniformly spaced and exhibit sharper, well-defined boundaries even at reduced substrate temperatures. XRD analysis confirmed that plasma-assisted EB-PVD processes allow for maintaining the desired tetragonal phase of YSZ without inducing secondary phases or unwanted texture changes. These findings indicate that plasma-assisted EB-PVD can achieve desirable coating characteristics (uniform thickness and optimised columnar structure) more efficiently, offering potential advantages for high-temperature applications in aerospace and power-generation industries. Continued development of the EB-PVD process with the assistance of plasma generation could further improve deposition rates and TBC performance, underscoring the promising future of HC-assisted EB-PVD technology. Full article