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Social interactions (e.g. aggression, mating and parenting) often depend on the social environment, and recent studies suggest that the adult sex ratio (ASR, the proportion of males in the adult population) modulates these social interactions. While observational studies and phylogenetic analyses provide strong support for the proposition that the relative frequencies of adult males and females impact social decisions, the experimental evidence for the impacts of ASR on social interactions is moot. In this study, we manipulated ASR in dung beetles, Onthophagus taurus , to test the responses of males and females in contest behaviour, courtship behaviour and breeding success. We found that ASR influenced the intensity of both contest and courtship, with both contests and courtships being more frequent in male-biased ASRs than in female-biased and unbiased treatments. The weight of brood balls did not differ significantly between ASR treatments, suggesting that ASR does not affect the breeding success of dung beetles by changing the parental investment of females and males. Moreover, the mean number of brood balls per male was fewer in male-biased treatments than in female-biased and unbiased treatments, while there was no significant difference in the mean number of brood balls per female between treatments, supporting the hypothesis that a male-skewed ASR can impair the breeding success of organisms by influencing the reproductive capacity of males but not females. Our results extend the understanding of the influence of ASR on the reproductive strategy decisions of males and females in breeding success. Future analyses are needed to understand the physiological and genetic implications of mate choice and contest behaviour in the context of a variable social environment, as represented by ASR. • An increased male-biased ASR frequently intensifies contest and courtship behaviour. • ASR shows no impact on parental care, evidenced by consistent brood ball weights. • ASR shifts male, not female, reproductive capacity, impacting breeding success. • There is no ASR effect on the parental care–fecundity trade-off in our experiment. [ABSTRACT FROM AUTHOR]

Transgenerational effects, which involve both selection and plasticity, are important for the evolutionary adaptation of echinoderms in the changing ocean. Here, we investigated the effects of breeding design and water temperature for offspring on fertilization, hatchability, larval survival, size, abnormality and metamorphosis of the sea urchin Strongylocentrotus intermedius , whose dams and sires were exposed to long-term (~15 months) elevated temperature (~3 °C above ambient) or ambient temperature. There was no transgenerational effect on fertilization and metamorphosis of S. intermedius , while negative transgenerational effects were found in hatchability and most traits of larval size. Dam and sire effects were highly trait and developmental stage dependent. Interestingly, we found S. intermedius probably cannot achieve transgenerational acclimation to long-term elevated temperature for survival provided their offspring were exposed to an elevated temperature. The present study enriches our understanding of transgenerational effects of ocean warming on sea urchins. [ABSTRACT FROM AUTHOR]

In this work, a novel strategy for high-quality AlN templates epitaxy on sapphire substrates with sputtered buffer layers combined with a low- and high-temperature alteration technique is proposed. The best full width at half maximum values for (0002) and (1 1 ¯ 02) reflections are 207 and 377 arcsec, respectively. Investigations indicate the joint effect of growth mode control and sputtered buffer layer results in the improvement of AlN crystalline quality. Firstly, threading dislocations density can be significantly decreased due to the alteration from three-dimensional to two-dimensional growth mode. Moreover, the graded composition of AlON layer in the sputtered buffer layer is believed to alleviate lattice mismatch between sapphire substrates and AlN, which also contributes to low dislocations density in AlN templates. [ABSTRACT FROM AUTHOR]

Abstract: Silver, titanium, nickel, and aluminum nanowire arrays with diameters from 90 to 110 nm were prepared on AAO templates by laser molecular beam epitaxy. On the several kinds of nanowire arrays, high-quality surface-enhanced Raman scattering (SERS) spectra of probe molecules of the red dye Sudan II (C18H16N2O) were obtained. In particular, the SERS spectrum of Sudan II on an aluminum nanowire array is reported for the first time. [Copyright &y& Elsevier]

K. Peppel, L. Zhang, T. T. T. Huynh, X. Huang, A. Jacobson, L. Brian, S. T. Exum, P.-O. Hagen and N. J. Freedman. Overexpression of G Protein-Coupled Receptor Kinase-2 in Smooth Muscle Cells Reduces Neointimal Hyperplasia. Journal of Molecular Cellular Cardiology (2002) 34, 1399–1409. The activation of vascular smooth muscle cells (SMCs) in neointimal hyperplasia involves signaling through receptor tyrosine kinases as well as G protein-coupled receptors. Overexpression of G protein-coupled receptor kinase-2 (GRK2) in SMCs can attenuate mitogenic signaling and proliferation in response to not only several G protein-coupled receptor agonists, but also platelet-derived growth factor (PDGF). To test whether overexpression of GRK2 could inhibit other SMC responses implicated in neointimal hyperplasia, we assessed SMC chemotaxis and mitogenic signaling evoked by PDGF and Gq-coupled receptor agonists. To test the effects of GRK2 overexpression on neointimal hyperplasia in vivo, we employed a rabbit autologous vein graft model system. GRK2 overexpression reduced PDGF-promoted SMC chemotaxis by 85% (P<0.01), but had no effect on chemotaxis promoted by epidermal growth factor (EGF). Congruently, GRK2 overexpression reduced by ∼50% (P<0.05) the [3H]thymidine incorporation induced by combinations of PDGF and Gq-coupled receptor agonists, but had no effect on that induced by PDGF plus EGF. PDGF-, but not EGF-promoted phosphoinositide 3-kinase activity in SMCs was also inhibited by GRK2 overexpression. In rabbit vein grafts, we achieved GRK2 overexpression in medial SMCs, reduced cell proliferation during the first week after graft implantation, and reduced steady state neointimal thickness by 29% (P<0.01), without affecting medial thickness or potentiating SMC apoptosis. Because of its ability to dampen chemotactic and mitogenic signaling through PDGF and Gq-coupled receptors, GRK2 overexpression in SMCs may be a useful therapeutic approach for neointimal hyperplasia. [Copyright &y& Elsevier]

Polycyclic aromatic hydrocarbons (PAHs) are significant petroleum pollutants that have long-term impacts on human health and ecosystems. However, assessing their toxicity presents challenges due to factors such as cost, time, and the need for comprehensive multi-component analysis methods. In this study, we utilized network toxicity models, enrichment analysis, and molecular docking to analyze the toxicity mechanisms of PAHs at different levels: compounds, target genes, pathways, and species. Additionally, we used the maximum acceptable concentration (MAC) value and risk quotient (RQ) as an indicator for the potential ecological risk assessment of PAHs. The results showed that higher molecular weight PAHs had increased lipophilicity and higher toxicity. Benzo[a]pyrene and Fluoranthene were identified as core compounds, which increased the risk of cancer by affecting core target genes such as CCND1 in the human body, thereby influencing signal transduction and the immune system. In terms of biological species, PAHs had a greater toxic impact on aquatic organisms compared to terrestrial organisms. High molecular weight PAHs had lower effective concentrations on biological species, and the ecological risk was higher in the Yellow River Delta region. This research highlights the potential application of network toxicity models in understanding the toxicity mechanisms and species toxicity of PAHs and provides valuable insights for monitoring, prevention, and ecological risk assessment of these pollutants. • We analyzed the toxicity patterns of 19 polycyclic aromatic hydrocarbons at the levels of compound, gene, pathway, and species toxicity for the first time using a network toxicity model. • The molecular docking results validated the reliability of the analysis results obtained from the network toxicity model. [ABSTRACT FROM AUTHOR]

Double peaks at wavelength of 276 and 290 nm are observed for AlGaN/AlGaN multiple quantum wells (MQWs). Cathodoluminescence (CL) mappings identify that the emission at 290 nm originates from the macrostep edges. Potential minima induced by local variation of QW thickness and Ga incorporation are found along the step edges, where quantum wires (QWRs) are formed. The lateral advance rate of macrostep (∼310 nm/h) is obtained by investigating the distribution of QWRs. Temperature-dependent CL spectrum suggest that thermal quenching for 290 nm emission is dramatically suppressed compared with that for conventional QWs emission, which shows excitonic localization characteristics of QWRs. [ABSTRACT FROM AUTHOR]

Phosphate concentrations in eutrophic surface waters are usually low, and efficient removal of low concentration phosphate remains a challenge. In this study, Ca-doped LaMnO 3 synthesized at doping ratios, designated as Ca x La 1-x MnO 3 (x = 0, 0.2, 0.4, 0.7), were compared. It was found that, the adsorption capacity of Ca 0.4 La 0.6 MnO 3 material reached 63.01 mg/g at pH = 5, increased by 63.6% over the undoped LaMnO 3 perovskite. For long-term adsorption, Ca 0.4 La 0.6 MnO 3 could constantly adsorb phosphate to avoid phosphate accumulation (<0.05 mg/L). This proves that Ca 0.4 La 0.6 MnO 3 has the ability to control dynamic water eutrophication. Characterization and density functional theory results confirmed that Ca x La 1-x MnO 3 can increase the content of mesopores and oxygen vacancies, providing additional active sites. This reduces the adsorption energy of the La site, promotes electron transfer, and increases its affinity. It provides a new method for removing low-concentration phosphates. [Display omitted] • Synthesis of Ca doped LaMnO3 perovskites by solvothermal. • LaMnO3 perovskites with Ca A-site doping exhibited emptier orbital structure. • Efficient trace phosphate from water with Ca-doped LaMnO3 perovskite (∼99.76 %). • Electron transfer occurs between the O 2p and (110) surfaces, La as the most active site. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Photoperiod, moderated by temperature, is the major factor governing prepupal diapause induction in Chrysopa formosa. • Third instar larvae are most sensitive to photoperiod. • Chilling at 5 °C for 60 days is sufficient for diapause termination. • Diapausing chrysopids can be stored up to 300 days at 5 °C. Abstract Knowledge of environmental regulation of diapause in the green lacewing Chrysopa formosa , an important polyphagous predator against various pests, is essential for understanding seasonal adaptations of insects and for increasing the shelf-life and shipment of chrysopids used in biological control programs. In the present study, we identified environmental factors responsible for induction and termination of diapause and cold tolerance in this chrysopid. C. formosa exhibits a facultative, prepupal diapause within its cocoon. The free-living third instar larva is the stage most sensitive to photoperiodic stimuli. Photoperiod is the major factor governing the induction of prepupal diapause, and temperature exerts a modulating effect. Photoperiodic response curves for C. formosa showed a typical long day response over a wide range of temperatures. Critical daylength for diapause induction was estimated to be 14.3 h at 20 °C, with a shift towards short daylengths at higher temperatures. The diapause response was maximal with a short daylength of 8L: 16D at 18 °C or 20 °C, and no diapause was induced under 16L: 8D at any temperature examined. Chilling temperature had a pronounced effect on the completion of diapause termination and post-diapause development. A chilling period of 60 days or more at 5 °C was sufficient to terminate diapause in most prepupae. An increase of chilling exposure duration synchronized post-diapause development and adult emergence. What was particularly attractive is that diapausing chrysopids could be stored at 5 °C as long as 300 days with high survival and short adult emergence time. The developmental period prior to diapause was extended significantly for diapause-destined chrysopids. Prepupal diapause in C. formosa distinctly enhanced the cold tolerance. These results suggest mechanisms that could be exploited to improve shelf-life and long distance shipment of chrysopids for release in biological control program. [ABSTRACT FROM AUTHOR]

The anion exchange properties of layered composite metal hydroxide (LDHs) make it a significant anion purification material in aquatic environment. Ca–Al-LDHs as a calcium-based adsorbent can significantly improve the removal rate of phosphate. In this manuscript, waste oyster shell was used as the source of calcium and waste cans as the source of aluminum, and compared with the LDHs prepared by chemical reagents. The optimal molar ratio of for both the types of materials prepared from waste material as well as reagents was found to be 4:1 for best adsorption performance, with the waste group and reagent group materials showing similar adsorption capacities of 127.50 mg g−1 and 126.67 mg g−1, respectively. The effects of adsorbent dosage, initial solution pH and presence of coexisting ions on the adsorption capacity were investigated. Langmuir adsorption isotherm, quasi-second-order kinetic equation and mass transfer kinetics was found to describe the phosphorus adsorption process of CAs-4 and CA-4 in better way. The maximum adsorption capacities of Langmuir equation for CAs-4 and CA-4 adsorption process were 126.41 mg g−1 and 127.43 mg g−1, respectively, for CAs-4 and CA-4. The characterization results of FTIR, XRD and ICP showed that the main adsorption mechanisms were intercalation anion exchange, electrostatic attraction and dissolution precipitation. This work not only provides a method to prepare Ca–Al-LDHs for efficient utilization of solid waste, but also provides theoretical significance for controlling water eutrophication and realize waste recycling. • Preparation of Ca–Al-LDHs is an effective way to realize solid waste recycling. • Ca–Al-LDHs and reagent LDHs have similar adsorption capacity for phosphate. • The main mechanism of phosphate adsorption by Ca–Al-LDHs is anion exchange. [ABSTRACT FROM AUTHOR]