Search Results (573)

Agricultural intensification in Eastern Africa has raised concerns about the transport of pesticides and nutrients from farmland into surface waters, posing risks to ecosystems and human health. This study systematically reviews the peer-reviewed literature published between 2010 and 2024 to assess the extent, patterns, and drivers of agrochemical contamination in rivers, lakes, and reservoirs across the region. Reported pesticide concentrations ranged from <0.01 to 0.55 μg L⁻¹, with several studies indicating exceedances of drinking-water or environmental guideline values, particularly for organophosphate and carbamate compounds. Nutrient enrichment was widespread, with nitrate concentrations of 0.99–5.6 mg L⁻¹ and phosphate levels of 0.16–2.0 mg L⁻¹, frequently linked to eutrophication. Many studies showed strong seasonal variability, with higher concentrations during rainy periods due to increased runoff and erosion. Variability among findings reflected differences in land use, catchment characteristics, sampling design, and analytical approaches. Where evaluated, mitigation measures such as vegetated buffer strips, cover cropping, and improved nutrient management were associated with reductions in agrochemical runoff of approximately 50–80%. Overall, agrochemical contamination is widespread across Eastern African basins and influenced by agricultural practices and hydrological dynamics, highlighting the need for strengthened monitoring, improved stewardship, and broader adoption of mitigation strategies. Full article

To address the common drawbacks of polyamine-based CO₂ absorbents, such as high viscosity and precipitation at high CO₂ loading, a novel liquid–liquid biphasic absorbent composed of triethylenetetramine (TETA), 1-(2-aminoethyl)piperazine (AEP), N,N-dimethylacetamide (DMAC), and H₂O was developed in this study. By comprehensively evaluating CO₂ saturation loading, phase separation behavior, rheological properties of the CO₂-rich phase, precipitation suppression, and desorption–regeneration performance, the optimal absorbent formulation was identified as 20 wt% TETA + 10 wt% AEP + 40 wt% DMAC + 30 wt% H₂O. The optimized system enabled more than 98% of the CO₂ absorption products to be concentrated in the lower phase, which accounted for only 56% of the total liquid volume. Compared with the AEP-free TETA/DMAC/H₂O system, the optimized AEP-modified absorbent effectively eliminated precipitation and reduced the viscosity of the CO₂-rich phase to 62.3 mPa·s, while also improving the desorption behavior and cyclic stability of the system. In addition, ¹³C NMR analysis suggested that the salting-out effect is the main driving force for phase separation, with ionic products preferentially enriched in the aqueous phase to form the CO₂-rich lower phase. AEP contributes to viscosity reduction, precipitation suppression, and enhanced regeneration by weakening carbamate aggregation through steric hindrance and promoting bicarbonate formation. Full article

A hybrid method combining biomimetic liquid chromatography with immobilized artificial membrane (IAM) and quantitative structure–activity relationships (QSARs) was used to derive helpful models for predicting selected properties related to distribution (binding to human serum albumin (log P_w/HSA)) and absorption (skin permeation (log K_w/sp), plant cuticle permeation (log P_w/pc), and human intestinal permeability (Caco-2)), and therefore influencing the effectiveness or unwanted effects of 199 synthetic compounds that are regarded as potential drugs or plant protection products. The molecules under investigation—derivatives of 5H-6,7-dihydroimidazo [2,1-c][1,2,4]triazole, 7,8-dihydroimidazo[2,1-c][1,2,4]triazin-4(6H)-one, 2,6,7,8-tetrahydroimidazo[2,1-c][1,2,4]triazine-3,4-dione, 1H-1,2,4-triazole, carbamic and phenoxyacetic acid—differ in their properties but all meet the requirements for xenobiotics to be considered as medicinal products. Reliable high-concept models were developed, indicating lipophilicity, molecular size, electronic properties, and the number of rotatable bonds as descriptors that determine the biological properties of these compounds. These models have been optimized and cross-validated, confirming their reliability and high predictivity. Full article

A TiO₂/hydrazine system was investigated as a proof-of-concept platform for coupling chemical CO₂ capture with light-driven H₂ evolution under UV irradiation. Hydrazine served as the CO₂ capture agent, leading to the formation of carbamate-type intermediates, while TiO₂ acted as the photoresponsive solid. FT-IR, UV-Vis, and mass spectrometry analyses supported carbamate formation after CO₂ uptake and confirmed H₂ generation during irradiation, reaching a maximum of 33.2 μmol under the conditions evaluated. Deuterated experiments showed no detectable HD or D₂, indicating that H₂ evolution predominantly proceeded via hydrazine dehydrogenation rather than direct water splitting. On the basis of the available spectroscopic evidence, a tentative pathway involving carbamate intermediates and nitrogen-containing oxidation products is proposed. However, key control experiments required to confirm a strictly photocatalytic origin of H₂ evolution were not performed in the present exploratory study. Therefore, the observed behavior is more appropriately interpreted as preliminary photoinduced reactivity in a TiO₂/hydrazine/CO₂ system rather than definitive proof of a fully established photocatalytic mechanism. Overall, the results establish a preliminary proof of concept, while the limitations related to control experiments, product identification, quantification, and reproducibility are recognized. Full article

Against the global carbon neutrality backdrop, amine-based CO₂ capture technology is critical for industrial greenhouse gas emission reduction. However, mixed amine absorbents can cause severe corrosion of Q235B carbon steel, restricting the stable operation of carbon capture, utilization, and storage (CCUS) projects. This study systematically investigated the corrosion behavior of Q235B carbon steel in a novel mixed amine system under simulated industrial conditions using weight loss tests, electrochemical measurements (EIS, potentiodynamic polarization), and advanced characterizations (FT-IR, ¹³C NMR, SEM-EDS, XRD). The temperature was the dominant factor: corrosion rate increased significantly with rising temperature. Under CO₂-saturated conditions, 15–30% absorbent concentrations showed no significant effect on corrosion rate owing to similar molar loading and pH. At 60 °C and 30% concentration, the corrosion rate peaked at 30 L/L CO₂ loading. Carbamate accumulation promoted corrosion at low loading, while increased bicarbonate inhibited corrosion at high loading. The main corrosion products (Fe₃O₄, Fe₂O₃) formed loose, porous films with poor protectiveness. This work clarifies the electrochemical corrosion mechanism and provides data support for corrosion prevention in CCUS equipment. Full article

The BODIPY core has emerged as a versatile scaffold for the design of photoremovable protecting groups (PPGs). Herein, we report the synthesis of a novel BODIPY–epinephrine conjugate linked via a carbamate moiety, enabling light-triggered release of the active compound (epinephrine, also known as adrenaline). The structure of the obtained product was confirmed by ¹H and M ¹³C NMR spectroscopy as well as high-resolution mass spectrometry (HRMS). The described conjugate represents a potential tool for the photoactivated modulation of biologically relevant processes. Full article

This study investigates strategies to reduce mould growth on steamed beech wood by evaluating drying-based and fungicide-based protection approaches. The drying-based approach focused on optimising the temperature of warm-air drying parameters to control moisture content and limit mould development. The fungicide-based approach involved testing selected agents, including 3-iodo-2-propynyl butyl carbamate, boric acid, quaternary ammonium compounds, and nano-ZnO, for their effectiveness in preventing mould formation. Mould growth was assessed by macroscopic observation and classified according to standardised intensity levels. The results indicate that adjusting drying parameters alone is insufficient to prevent mould growth, whereas specific fungicide treatments provide effective surface protection. These findings offer practical guidance for minimising mould development on beech wood during drying and storage. Full article

The development of protective coatings that integrate self-healing and environmental tolerance is vital for extending substrate lifespan. In this study, a multifunctional hydrogel composite coating is developed based on a waterborne polyacrylate dynamic covalent network containing oxime–carbamate bonds. The functional monomer MEOC, which contains an oxime–carbamate dynamic bond, was synthesized and incorporated into the waterborne polyacrylate matrix to form a hydrogel network (OC-PA) with intrinsic self-healing capability. Prussian blue (PB) and nano-SiO₂ were incorporated to form a photothermal functional layer, imparting hydrophobicity and converting light into heat for de-icing, while also activating dynamic bond rearrangement within the substrate. When the MEOC content was 7 wt% and the PB content was 2 wt%, the coating temperature rose to 110 °C within 2 min under 0.6 W/cm² irradiation, and the scratch healed within 5 min. After 1 h of fracture repair, the tensile strength reached 6.68 MPa, with a repair rate as high as 92.91%, and de-icing time was reduced from 343 s to 183 s. The coating achieved a water contact angle >100°. At −20 °C, the icing delay time increased by 215%. The hydrogel coating also exhibited excellent abrasion resistance, chemical stability, UV aging resistance, and anti-fouling properties, offering a durable solution for demanding environments. Full article

Although amine-based post-combustion carbon capture is among the most established routes for CO₂ capture, it suffers from the high energy demand associated with amine regeneration. Recent research proposals suggest that microwave or frequency-tuned infrared heating may lead to more efficient amine regeneration processes. However, such approaches inherently introduce oscillating electromagnetic fields whose non-thermal effects on reaction pathways and energetics remain poorly understood. In this series paper, we employ high-accuracy quantum computational chemistry calculations to quantify the non-thermal effects of external electric fields on CO₂ absorption and desorption in monoethanolamine (MEA) and triethanolamine (TEA) under both aqueous and non-aqueous conditions. In this first part, we focus on static electric fields in order to establish a mechanistic reference framework helpful for interpreting non-thermal effects arising from frequency-tuned infrared laser excitation, which are addressed in Part II of this series. Our results show that static electric fields stabilize CO₂–amine reaction products, lowering absorption barriers, while consistently increasing both activation energies and reaction enthalpies associated with the amine regeneration process. This effect is particularly pronounced for MEA, where carbamate species become progressively more resistant to conversion to zwitterion as the field strength increases. These findings demonstrate that non-thermal static electric field effects counter the fundamental requirement for low-energy amine regeneration. By defining this intrinsic mechanistic limitation, the present study provides a useful baseline for assessing infrared laser-assisted carbon capture and underscores the importance of carefully selecting excitation frequencies to avoid adverse non-thermal stabilization effects. Full article

LiAlH₄ reduction of tert-butyl (S)-butyl(1-((2-cycloheptylethyl)amino)-1-oxo-3-phenylpropan-2-yl)carbamate (1) gave imidazolidine 2, while treatment with lithium diisopropylamide furnished the β-elimination product, cinnamamide 3. Both products were fully characterized. Reductive cyclization of N-alkylated-N-Boc-protected amino acid amides with LiAlH₄ may be a viable synthetic method for trisubstituted chiral imidazolidines. Full article

This study developed poly(lactic acid) (PLA) biocomposites reinforced with pine wood flour (10, 20, and 30 wt%) to achieve the interphase through chemical modification. Specifically, the wood flour was treated with poly(propylene glycol) toluene 2,4-diisocyanate terminated (PEGTDI), while 1 wt% poly(lactic acid)-g-maleic anhydride (PLA-g-MA) was integrated as a reactive compatibilizer during extrusion and thermocompression. Fourier-transform infrared spectroscopy (FTIR) analysis corroborated the occurrence of urethane formation and ester/anhydride linkages, as substantiated by the presence of characteristic bands indicative of surface carbamation at 1645 and 1726 cm⁻¹. Thermal analysis revealed that both the pine wood flour and coupling agents promoted PLA crystallization; however, thermogravimetric analysis (TGA) indicated a decrease in thermal stability for functionalized composites, suggesting a trade-off between enhanced interfacial interaction and heat resistance. Mechanical testing demonstrated a significant reinforcement effect, with the Young’s modulus increasing by up to 22% in untreated composites. The coupling agents effectively optimized stress transfer at low fiber loadings (10 wt%), while flexural modulus improvements were predominant at higher loadings (20–30 wt%) regardless of treatment. These findings underscore the criticality of surface modification and compatibilizer selection for tailoring the structural and thermo-mechanical properties of PLA-based biocomposites, thereby providing a pathway for optimized performance in structural applications. Full article

Developing environmentally friendly, multifunctional waterproof and breathable membranes (WBMs) has attracted extensive attention and is of great significance but remains challenging. Herein, an environmentally friendly and multifunctional waterborne polyurethane WBM with self-healing and self-cleaning properties is developed in two steps. Firstly, by using polydimethylsiloxane (PDMS) as a hydrophobicity giver and tannic acid (TA) as a crosslinker, a dual-modified waterborne polyurethane (PTWPU) is prepared, which has high surface hydrophobicity due to the surface enrichment of siloxane segments and self-healing performance from the formation of a dynamic phenolic carbamate network. Secondly, by incorporating titanium dioxide (TiO₂) photocatalyst nanoparticles to increase internal porosity and establish hydrophilic pathways, a multifunctional waterborne polyurethane WBM (TPTWPU) is developed. This membrane features further enhanced surface hydrophobicity from generated micro-roughness and effective self-cleaning performance, because TA acts as an electron trap to promote the photocatalytic activity of TiO₂. The TPTWPU membrane shows good hydrophobicity (water contact angle of 115.3°) and satisfactory moisture permeability of 135.0 g/(m²·24 h), which is 61.2% higher than unmodified membranes. Furthermore, it exhibits efficient self-healing, with a recovery rate exceeding 80% within 2 h. This feasible strategy will provide guidance for materials design in multifunctional coatings for textiles and leather. Full article

Forensic veterinary pathology is becoming increasingly important in investigating situations of suspected animal abuse. In Trinidad and Tobago, there are only two veterinary diagnostic laboratories capable of performing necropsies, one at the University of the West Indies School of Veterinary Medicine (UWI-SVM) and the other at the Ministry of Agriculture and Fisheries, Veterinary Diagnostic Laboratory (MAF-VDL). The databases of both UWI-SVM and MAF-VDL were searched for cases of suspected animal abuse between 2008 and 2025. Based on pathology records and case submission information, cases were categorized by year, species, cause of death (COD) or manner of injury (MOI), police submissions, and types of trauma and poisonings. A total of 113 cases of suspected animal abuse were submitted in the years 2008–2025. Case submissions reached a peak in 2015 (n = 23). The most submitted animal species was dogs (77%). Of the 113 cases, only 24 (20%) had a confirmed COD/MOI. The most common confirmed COD/MOI was trauma. The few confirmed cases of poisoning (n = 6) include carbamates, warfarin, malathion, and ethylene glycol. Owners appear to be aware of the importance of pathology to help diagnose suspected animal abuse cases. One major limitation in advancing forensic veterinary pathology on the island, and a factor preventing the prosecution of suspected animal abuse cases, is the lack of a toxicological laboratory capable of handling animal samples. Full article

The preservation of biological control agents in agroecosystems while simultaneously ensuring the use of insecticides with selective chemical profiles is crucial for sustainable pest management. In this study, we aimed to evaluate the selectivity of insecticides used in the management of Phthorimaea (Tuta) absoluta in tomato crops during the adult stage of Trichogramma pretiosum. The selectivity tests were conducted according to the standards of the International Organization for Biological and Integrated Control/West Palearctic Regional Section. The bioassay was used to assess the direct effects of treatments on T. pretiosum adults through tarsal contact. Specifically, 42 chemical and/or biological insecticides commonly applied in tomato cultivation were used to manage P. absoluta. The insecticides identified as selective (Class 1) for adult T. pretiosum under laboratory conditions were recommended for use in integrated pest management (IPM) programs in tomato crops. These included Hayate^®, Agree^®, Dipel^®, Xentari^®, Tarik^®, Bioexos^®, Verpavex^®, Spodovir^®, Verpavex^® + Spodovir^®, Tuta Vir^®, BioBrev^®, Diplomata^®, VirControl C.i^®, and VirControl S.F^®. Insecticides belonging to the following chemical groups were not selective, that is, they were harmful to T. pretiosum adults: avermectins, milbemycins, diacylhydrazines, oxadiazines, semicarbazones, spinosyns, diamides, chlorfenapyr, nereistoxin analogs, pyrethroids, carbamates, butenolides, isoxazoline, azadirachtin, quinolizidine alkaloids, METI, and benzoylureas. Therefore, these insecticides should be used with caution in IPM programs that target P. absoluta in tomato crops. Full article

Cyantraniliprole, a second-generation diamide insecticide, exhibits broad-spectrum efficacy against numerous insect pests due to its selective activation of insect ryanodine receptors (RyRs). This activation triggers uncontrolled calcium release from the sarcoplasmic reticulum, resulting in sustained muscle contraction, paralysis, and ultimately death. Its unique mode of action, which is different from that of organophosphates, carbamates, pyrethroids, and neonicotinoids, helps minimize cross-resistance, making it a valuable component of integrated pest management (IPM). However, continuous field use has led to the development of resistance, primarily mediated by target-site mutations within the RyR transmembrane domain (e.g., G4946E, I4743M, and I4790K) and by enhanced metabolic detoxification via cytochrome P450 monooxygenases, carboxylesterases, and glutathione S-transferases. These mechanisms often confer cross-resistance to other diamide insecticides, thereby complicating resistance management. Moreover, sublethal exposures can disrupt insect growth, development, and reproduction, potentially accelerating resistance evolution. In addition, cyantraniliprole poses ecological risks due to its toxicity to non-target organisms such as aquatic species, including zebrafish and water fleas, pollinators such as honeybees, and soil fauna, as well as the environmental persistence of its major metabolite, J9Z38. This review comprehensively integrated current knowledge on the molecular mechanisms of action, genetic and metabolic bases of resistance, sublethal effects, and ecotoxicological impacts of cyantraniliprole, along with its environmental fate, plant uptake and translocation, and residue dynamics in agricultural systems. Finally, we discuss potential risk-mitigation strategies, including formulation optimization, application-method improvements, and resistance monitoring. Overall, this review aims to provide a comprehensive scientific foundation for the sustainable use, resistance management, and regulatory assessment of this widely used insecticide. Full article