Browse Articles

Synthesis, SAR, and in silico studies of new benzochromene derivatives as insecticidal agents against Culex pipiens L. larvae and adults

Abstract Mosquito control is a favorable strategy to prevent mosquito-borne diseases. There are various approaches for the management of potentially dreadful mosquito populations such as larvicides and adulticides. In this study, a series of novel benzochromene derivatives were synthesized and evaluated for their insecticidal efficacy against larvae and adult stages of Culex pipiens L. The synthesized compounds underwent comprehensive structural characterization and toxicological evaluation, revealing their larvicidal and adulticidal activity for several derivatives. The tested compounds were more effective against larvae than adults of C. pipiens . Compounds 10 and 5 exhibited pronounced larvicidal activity, surpassing the reference compound temephos, with LC₅₀ values of 40.15 and 46.17 ppm, respectively. In addition, both compounds displayed remarkable adulticidal efficacy, with LC₅₀ values of 55.02 and 65.43 ppm, respectively, whereas compound 6 showed the lowest potency among the tested series with LC₅₀ value of 215.40 ppm. Notably, compounds 10 and 5 were 5.36- and 4.66-fold more active against larvae than compound 6 , and demonstrated 5.28- and 4.44-fold higher adulticidal efficiency compared with deltamethrin. In cytotoxicity assays, compound 5 displayed an IC₅₀ value of 72.65 µM, while compound 10 showed an IC₅₀ of 90.32 µM, indicating low toxicity toward normal human cells and a favorable selectivity index. Molecular docking supported this observation by demonstrating strong and specific binding interactions with Anopheles gambiae acetylcholinesterase (AChE). Additionally, the DFT results provided insights into the electronic properties and stability of the compounds, while MEP mapping highlighted key reactive sites associated with target interactions. Structure–activity relationship (SAR) studies identified crucial functional groups influencing insecticidal potency.

Adaptive contextual memory network for enhanced communication and efficiency in the internet of underwater things

Compressibility characteristics and coefficient of consolidation determination for unsaturated sand treated with micro silica

Impact of endometrioma on iron levels and oxidative stress in the follicular fluid in women with endometriosis: a cross-sectional study

Risk factors for pulmonary function alterations in children with metabolic dysfunction-associated fatty liver disease

Decoding dog communication through the physiology and behavior of urine marking

Diversified, endothelial cell-dependent cancer cell response to hypertensive serum modified by antihypertensive drugs

Growth mechanism of segregated ice and its influence on frost heave characteristics during horizontal freezing

Indoor space intelligent design method based on improved Resnet neural network

Experimental investigation of divalent ions and CTAB effects on heavy oil emulsion stability in carbonate reservoirs

Platelets in angiogenesis and pulmonary progenitor cell homing under chronic intermittent hypoxia

Cu-MOF as a saturable absorber for mode-locking at 2 µm and beyond

The additive effect of sarcopenia and osteoporosis on all-cause mortality: a cohort analysis in a U.S. population

Bio-based cellulose membrane from Phlomis tuberosa L. for methylene blue dye removal from wastewater and molecular interaction mechanisms

Influencing factors and spatiotemporal heterogeneity of land-use carbon emissions in China’s urban agglomerations

Abstract In the context of global climate change and rapid urbanization, understanding the relationship between land use and carbon emissions is critical for sustainable development. This study investigates carbon emissions from land use and their intensity in China’s five major urban agglomerations, including Beijing-Tianjin-Hebei, Yangtze River Delta, Middle Reaches of Yangtze River, Pearl River Delta, and Chengdu-Chongqing, from 2000 to 2020. By integrating land-use and socio-economic data with geographic information systems, the Logarithmic Mean Divisia Index model, and the Kaya Identity, we analyze the spatiotemporal differentiation and evolution of carbon emissions and intensity, as well as the influencing factors behind these trends. Additionally, the Markov prediction method is employed to project land-use changes and carbon emission trends through 2025. The results indicate that the Pearl River Delta exhibited the fastest the most rapid increase in land-use carbon emissions during the study period, while simultaneously achieving the lowest land-use carbon emission intensity among all regions. Economic development and industrial structure served as the principal drivers of emission growth, whereas energy consumption intensity exerted a mitigating effect in all urban agglomerations. Despite the growing proportion of clean energy, the influence of energy structure on emission reduction remained limited, indicating a persistent dependence on fossil fuels. This study underscores the complex relationship between land use and carbon emissions in urban agglomerations, offering important insights for policy formulation. The findings emphasize the necessity of developing targeted strategies to reconcile economic growth with carbon reduction, thereby advancing sustainable land-use planning and supporting climate change mitigation and regional sustainability.

Randomized open-label non-inferiority trial of paracetamol or celecoxib for patients with chronic low back pain

Control of limb loading during active horizontal perturbations at moderate and fast trots in rats

Abstract To understand how small animals cope with complex, unstructured, and unpredictable substrates, we analysed the kinetics of female rats ( $$n = 10$$ ) moving at a fast and at a moderate trot over an unperturbed substrate and a substrate subjected to active horizontal perturbations. Perturbations were active single forwards or backwards displacements of an instrumented platform by 5 mm or 10 mm amplitudes in 0.05 s. Single leg ground reaction forces (SLGRF) were collected for unperturbed and perturbed locomotion (hindlimbs: 50/102, forelimbs: 45/130, respectively). When negotiating horizontal perturbations, rats displayed gait resetting (braking, accelerating) and non-resetting behaviours. Feedforward strategies differed between the fore- and hindlimbs. In circa 60% of the perturbed trials, forelimbs started the step in acceleration mode, while hindlimbs began the stance mostly in non-resetting mode ( $$\sim$$ 45%). In about 50% of all perturbed steps, the impulse provided by the SLGRF displayed a change in behaviour according to the expected response to the perturbation. The remaining 50% retained the feedforward strategy. Still, most perturbed trials displayed changes in SLGRF patterns that indicated passive and active reactions to platform shifts. Our results indicate that rats’ sensorimotor control system tunes fore- and hindlimbs differently in expectation of a perturbation. In addition, the tendon-muscle systems of the limbs are recruited to prevent leg collapse at the beginning and end of the stance. At lower speeds, spinal and/or higher centre commands have enough time to re-adapt limb behaviour. At higher locomotion speeds, rats rely more on their limbs’ intrinsic stability and feedforward control.

An Atacama subsurface tephra layer reveals how life colonized Kenorland in the Neoarchean

Abstract Much has been published on the microbiology of the Atacama Desert, the driest and oldest place on Earth, but little is known about how microbial life is able to permanently colonize this extremely harsh environment. Given that wind transports vast amounts of viable microbial cells from the Pacific Ocean across the entire Atacama on a daily basis, it is difficult to identify the true native microbial inhabitants from recent arrivals. Here, we present a unique site—Mancha Blanca—located at the western edge of the Coastal Range of this desert. Containing a Miocene tephra subsurface layer, this site’s unique differential habitability unveils the fate of new arrivals, and thus, the identity and metabolic strategies of the species that are eventually able to adapt and become some of the true inhabitants of the Atacama. Our findings show that the extreme conditions of the Atacama stochastically select for species arriving from the Pacific Ocean that already possess the molecular mechanisms needed to tolerate salinity, and thus are capable of inhabiting the driest desert on Earth. The colonization processes still detectable in the regions studied allow us to suggest the mechanistic and evolutionary pathways that may have been involved in the colonization of Kenorland by microbial life from the Panthalassic Ocean during the Neoarchaean. We propose the Coastal Range/hyperarid core of the Atacama as a model system for understanding the colonization of land 2.6 billion years ago.

Low-light color image equalization based on adaptive brightness adjustment

Experimental investigation into shear behavior of loess-red clay composite interface under low-temperature environment

Abstract The shear behavior of the double-layer heterogeneous interface between loess and red clay is crucial for better understanding the formation and evolution mechanism of loess–red clay interface landslides in the Loess Plateau. However, the effects of low-temperature environment on the shear behavior of loess–red clay composite interface are given lesser attention. This study conducted freezing and direct shear tests on loess–red clay composites with different moisture contents to investigate the effects of moisture content and low temperature on the shear behavior of the interface. The results indicate that the shear strength of the interface decreases with increasing moisture content. Under high moisture contents (> 14%), the red clay tends to form aggregates, intensifying the double-layer heterogeneity and further decreasing shear strength. With decreasing temperature, the shear strength exhibits a three-stage trend of “increase (unfrozen stage (–2°C~ − 5°C))-decrease (transition zone (–5°C~ − 10°C))-increase (freezing stage (–10°C~ − 20°C))”, mainly attributed to water migration and water-ice phase transition evolution under different low-temperature environments. Considering the coupling effects of moisture content and temperature, the shear strength is divided into four intervals using a threshold of 14% moisture content (aggregation formation) and − 10 °C (freezing point). The average shear strength in each interval shows a negative correlation with moisture content, confirming that moisture content is the dominant factor affecting the shear strength of the interface. These findings can facilitate the disaster prevention and control of heterogeneous interface landslides and the security of major engineering construction in seasonal frost and permafrost loess areas.