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Recent efforts to evaluate the contribution of neonicotinoid insecticides to worldwide pollinator declines have focused on honey bees and the chronic levels of exposure experienced when foraging on crops grown from neonicotinoid-treated seeds. However, few studies address non-crop plants as a potential route of pollinator exposure to neonicotinoid and other insecticides. Here we show that pollen collected by honey bee foragers in maize- and soybean-dominated landscapes is contaminated throughout the growing season with multiple agricultural pesticides, including the neonicotinoids used as seed treatments. Notably, however, the highest levels of contamination in pollen are pyrethroid insecticides targeting mosquitoes and other nuisance pests. Furthermore, pollen from crop plants represents only a tiny fraction of the total diversity of pollen resources used by honey bees in these landscapes, with the principle sources of pollen originating from non-cultivated plants. These findings provide fundamental information about the foraging habits of honey bees in these landscapes. The extent to which non-crop plants may be contaminated by insecticides is not known. Here, the authors show that pollen collected by honey bees living in areas of intensive maize production is contaminated by a wide range of pesticides throughout the growing season, with the principle pollen source being non-crop plants.

Heart failure (HF) is the leading cause of death in patients with maintenance hemodialysis (MHD). Biomarkers has an important guiding role in the early diagnosis, risk stratification, and prognostic assessment of HF. Increasing studies have indicated that long non-coding RNAs (lncRNAs) have played an indispensable role in the regulatory network of HF. This study was aiming to explore the expression profiles of lncRNAs in patients treated with MHD developing heart failure. Peripheral blood mononuclear cells were isolated from 4 hemodialysis patients with reduced ejection fraction (HFrEF) and 4 hemodialysis patients with preserved ejection fraction (HFpEF), respectively. The expression profile analysis of lncRNAs was performed by using Illumina Novaseq 6000 sequencer. Quantitative real time polymerase chain reaction (qRT-PCR) was used to verify the expression of representative differentially expressed lncRNAs. Based on lncRNA-miRNA-mRNA-KEGG network analysis, the potential role of candidate lncRNAs and their association with the severity of HF were further evaluated. In total, 1,429 differentially expressed lncRNAs were found between patients with HFrEF and patients with HFpEF, of which 613 were up-regulated and 816 were down-regulated ( P  < 0.05). Five candidate lncRNAs were screened out by a series of bioinformatic analyses. After being compared with miRBase, ENST00000561762, one of the 5 candidates, was considered the most likely lncRNA to be serving as a precursor for miRNA. Nine predicted target genes were found by further lncRNA-miRNA-mRNA-KEGG network analysis, and among which ITGB5 was enriched in the actin dynamics signaling pathway. In another cohort of hemodialysis patients, the expression of lncRNA ENST00000561762 was verified by qRT-PCR. Further analysis revealed that there was a strong correlation between left ventricular ejection fraction and ENST00000561762, proBNP, and 6-minute walk distance, respectively. LncRNAs expression profile was remarkably different in hemodialysis patients with HFrEF compared to those with HFpEF. Among which, lncRNA ENST00000561762 was considered as a promising biomarker for patients with HFrEF as it was predicted to be a miRNA precursor to regulate the actin dynamics signaling pathway.

Recently, theoretical studies show that layered HfTe 5 is at the boundary of weak & strong topological insulator (TI) and might crossover to a Dirac semimetal state by changing lattice parameters. The topological properties of 3D stacked HfTe 5 are expected hence to be sensitive to pressures tuning. Here, we report pressure induced phase evolution in both electronic & crystal structures for HfTe 5 with a culmination of pressure induced superconductivity. Our experiments indicated that the temperature for anomaly resistance peak (Tp) due to Lifshitz transition decreases first before climbs up to a maximum with pressure while the Tp minimum corresponds to the transition from a weak TI to strong TI. The HfTe 5 crystal becomes superconductive above ~5.5 GPa where the Tp reaches maximum. The highest superconducting transition temperature (Tc) around 5 K was achieved at 20 GPa. Crystal structure studies indicate that HfTe 5 transforms from a Cmcm phase across a monoclinic C2/m phase then to a P-1 phase with increasing pressure. Based on transport, structure studies a comprehensive phase diagram of HfTe 5 is constructed as function of pressure. The work provides valuable experimental insights into the evolution on how to proceed from a weak TI precursor across a strong TI to superconductors.

Key message An innovative genotyping method designated as semi-thermal asymmetric reverse PCR (STARP) was developed for genotyping individual SNPs with improved accuracy, flexible throughputs, low operational costs, and high platform compatibility. Multiplex chip-based technology for genome-scale genotyping of single nucleotide polymorphisms (SNPs) has made great progress in the past two decades. However, PCR-based genotyping of individual SNPs still remains problematic in accuracy, throughput, simplicity, and/or operational costs as well as the compatibility with multiple platforms. Here, we report a novel SNP genotyping method designated semi-thermal asymmetric reverse PCR (STARP). In this method, genotyping assay was performed under unique PCR conditions using two universal priming element-adjustable primers (PEA-primers) and one group of three locus-specific primers: two asymmetrically modified allele-specific primers (AMAS-primers) and their common reverse primer. The two AMAS-primers each were substituted one base in different positions at their 3′ regions to significantly increase the amplification specificity of the two alleles and tailed at 5′ ends to provide priming sites for PEA-primers. The two PEA-primers were developed for common use in all genotyping assays to stringently target the PCR fragments generated by the two AMAS-primers with similar PCR efficiencies and for flexible detection using either gel-free fluorescence signals or gel-based size separation. The state-of-the-art primer design and unique PCR conditions endowed STARP with all the major advantages of high accuracy, flexible throughputs, simple assay design, low operational costs, and platform compatibility. In addition to SNPs, STARP can also be employed in genotyping of indels (insertion–deletion polymorphisms). As vast variations in DNA sequences are being unearthed by many genome sequencing projects and genotyping by sequencing, STARP will have wide applications across all biological organisms in agriculture, medicine, and forensics.

The mechanism of superconductivity in cuprates remains one of the big challenges of condensed matter physics. High-Tc cuprates crystallize into a layered perovskite structure featuring copper oxygen octahedral coordination. Due to the Jahn Teller effect in combination with the strong static Coulomb interaction, the octahedra in high-Tc cuprates are elongated along the c axis, leading to a 3dx²-y² orbital at the top of the band structure wherein the doped holes reside. This scenario gives rise to 2D characteristics in high-Tc cuprates that favor d-wave pairing symmetry. Here, we report superconductivity in a cuprate Ba₂CuO4-y, wherein the local octahedron is in a very exceptional compressed version. The Ba₂CuO4-y compound was synthesized at high pressure at high temperatures and shows bulk superconductivity with critical temperature (Tc ) above 70 K at ambient conditions. This superconducting transition temperature is more than 30 K higher than the Tc for the isostructural counterparts based on classical La₂CuO₄. X-ray absorption measurements indicate the heavily doped nature of the Ba₂CuO4-y superconductor. In compressed octahedron, the 3d3z²-r² orbital will be lifted above the 3dx²-y² orbital, leading to significant 3D nature in addition to the conventional 3dx²-y² orbital. This work sheds important light on advancing our comprehensive understanding of the superconducting mechanism of high Tc in cuprate materials.

AMP-activated protein kinase (AMPK) is an energy sensor that regulates cellular metabolism. When activated by a deficit in nutrient status, AMPK stimulates glucose uptake and lipid oxidation to produce energy, while turning off energy-consuming processes including glucose and lipid production to restore energy balance. AMPK controls whole-body glucose homeostasis by regulating metabolism in multiple peripheral tissues, such as skeletal muscle, liver, adipose tissues, and pancreatic beta cells--key tissues in the pathogenesis of type 2 diabetes. By responding to diverse hormonal signals including leptin and adiponectin, AMPK serves as an intertissue signal integrator among peripheral tissues, as well as the hypothalamus, in the control of whole-body energy balance.

Transition metal takes charge The introduction of 'foreign' elements into transition-metal oxides (called chemical doping) can change the valence state of the metal's cations and hence modify the physical properties of the material as a whole. These changes can be dramatic, for example causing high-temperature superconductivity in copper oxides and colossal magnetoresistance in manganese oxides. Youwen Long et al . have identified an oxide system, the perovskite LaCu 3 Fe 4 O 12 , in which changes in valence state occur when charge is shuffled between different cations (iron and copper) in the host structure, rather than via doping. As a result, the material can be reversibly transformed from one possessing iron in an unusually high Fe 3.75+ state (partnered with fairly common Cu 2+ ions) to one possessing rare Cu 3+ ions. These changes are reflected in the magnetic and electronic properties of the material and, intriguingly, the material contracts slightly on being warmed through the transition. The temperature sensitivity of this effect makes it a strong candidate for technological applications. This paper identifies an oxide system where changes in valence state occur as a result of charge being shuffled between different cations in the host structure, rather than via doping, this charge transfer being sensitive to temperature. As a result, the material can be reversibly transformed from one possessing iron in an unusually high Fe3.75+ state to one possessing rare Cu3+ ions. These changes are reflected in the magnetic and electronic properties of the material and, intriguingly, are accompanied by negative thermal expansion. Changes of valence states in transition-metal oxides often cause significant changes in their structural and physical properties 1 , 2 . Chemical doping is the conventional way of modulating these valence states. In ABO 3 perovskite and/or perovskite-like oxides, chemical doping at the A site can introduce holes or electrons at the B site, giving rise to exotic physical properties like high-transition-temperature superconductivity and colossal magnetoresistance 3 , 4 . When valence-variable transition metals at two different atomic sites are involved simultaneously, we expect to be able to induce charge transfer—and, hence, valence changes—by using a small external stimulus rather than by introducing a doping element. Materials showing this type of charge transfer are very rare, however, and such externally induced valence changes have been observed only under extreme conditions like high pressure 5 , 6 . Here we report unusual temperature-induced valence changes at the A and B sites in the A-site-ordered double perovskite LaCu 3 Fe 4 O 12 ; the underlying intersite charge transfer is accompanied by considerable changes in the material’s structural, magnetic and transport properties. When cooled, the compound shows a first-order, reversible transition at 393 K from LaCu 2+ 3 Fe 3.75+ 4 O 12 with Fe 3.75+ ions at the B site to LaCu 3+ 3 Fe 3+ 4 O 12 with rare Cu 3+ ions at the A site. Intersite charge transfer between the A-site Cu and B-site Fe ions leads to paramagnetism-to-antiferromagnetism and metal-to-insulator isostructural phase transitions. What is more interesting in relation to technological applications is that this above-room-temperature transition is associated with a large negative thermal expansion.

Objective: Hypoadiponectinemia has been proved to be closely related to endothelial dysfunction in peripheral arteries and is thought to be an independent risk factor for cardiovascular disease. The objective of this study was to investigate whether adiponectin might independently improve endothelial dysfunction in aorta isolated from high-fat-diet-induced obese. Sprague-Dawley rat and to study the mechanism involved. Research Design and Subjects: Male Sprague-Dawley rats were fed with a regular or a high-fat diet for 6 weeks. The aorta was isolated, and vascular segments were incubated with vehicle or the globular adiponectin (globular domain (gAD); 2 mg ml-1) for 2 h. The effect of gAD on endothelial function and nitric oxide (NO) production was determined. Human aortic endothelial cells in primary culture were treated with vehicle or gAD (4 mg ml-1). The effect of gAD on the level of phosphorylation of endothelial nitric oxide synthase (eNOS) at Ser1177, AMPK at Thr176 and Akt at Ser473 in endothelial cells were determined. Results: Severe endothelial dysfunction was observed in high-fat diet fed rat aortic segments. After gAd incubation, the endothelium-dependent relaxation was partly improved and total production of nitric oxide as result of enhanced eNOS activity was also increased. In the cultured endothelial cell line HUVEC, globular adiponectin increased the activity of eNOS through activating AMPK by stimulating its phosphorylation at Thr176 but not Akt. Conclusion: The demonstration in the current study that adiponectin reverses endothelial dysfunction through increasing NO production by eNOS phosphorylation, and decreasing NO inactivation by blocking superoxide production provides a new direction in the prevention of vascular injury in the obesity population.

Centrifugal pumps are widely used across various industries, and the design of high-efficiency centrifugal pumps is essential for energy savings and emission reductions. The development of centrifugal pump models primarily uses an iterative design approach combining direct and inverse problem-solving based on one-dimensional flow theory. However, this semi-empirical, semi-theoretical design process is time-consuming and costly. To reduce development time and costs, this paper proposes a rapid impeller design method focused on hydraulic performance, integrating traditional similarity design theory with machine learning. The proposed model uses neural networks to predict empirical coefficients, determine key dimensions such as the impeller’s inlet diameter, outlet diameter, outlet width, and axial distance. Once these parameters are defined, the main dimensions of the impeller can be calculated. The blade profile is defined using a 5-point B´ezier curve. Variations in the cross-sectional area of the flow passage influence the internal flow state of the centrifugal pump, ultimately impacting its hydraulic efficiency. A genetic algorithm, guided by variations in the cross-sectional area of the flow passage, optimizes the blade profile, achieving an improved impeller flow path and completing the rapid design of the centrifuge. This method significantly shortens the development cycle and lowers design costs, making it a promising technique for future impeller designs.

Photodynamic therapy (PDT) employs the combination of nontoxic photosensitizers and visible light that is absorbed by the chromophore to produce long-lived triplet states that can carry out photochemistry in the presence of oxygen to kill cells. The closed carbon-cage structure found in fullerenes can act as a photosensitizer, especially when functionalized to impart water solubility. Although there are reports of the use of fullerenes to carry out light-mediated destruction of viruses, microorganisms and cancer cells in vitro, the use of fullerenes to mediate PDT of diseases such as cancer and infections in animal models is less well developed. It has recently been shown that fullerene PDT can be used to save the life of mice with wounds infected with pathogenic Gram-negative bacteria. Fullerene PDT has also been used to treat mouse models of various cancers including disseminated metastatic cancer in the peritoneal cavity. In vivo PDT with fullerenes represents a new application in nanomedicine.