34 research outputs found

    Strong magnon-magnon coupling in an ultralow damping all-magnetic-insulator heterostructure

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    Magnetic insulators such as yttrium iron garnets (YIGs) are of paramount importance for spin-wave or magnonic devices as their ultralow damping enables ultralow power dissipation that is free of Joule heating, exotic magnon quantum state, and coherent coupling to other wave excitations. Magnetic insulator heterostructures bestow superior structural and magnetic properties and house immense design space thanks to the strong and engineerable exchange interaction between individual layers. To fully unleash their potential, realizing low damping and strong exchange coupling simultaneously is critical, which often requires high quality interface. Here, we show that such a demand is realized in an all-insulator thulium iron garnet (TmIG)/YIG bilayer system. The ultralow dissipation rates in both YIG and TmIG, along with their significant spin-spin interaction at the interface, enable strong and coherent magnon-magnon coupling with a benchmarking cooperativity value larger than the conventional ferromagnetic metal-based heterostructures. The coupling strength can be tuned by varying the magnetic insulator layer thickness and magnon modes, which is consistent with analytical calculations and micromagnetic simulations. Our results demonstrate TmIG/YIG as a novel platform for investigating hybrid magnonic phenomena and open opportunities in magnon devices comprising all-insulator heterostructures.Comment: 45 pages, 18 figures, and 2 table

    Gender differences in behavioral regulation in four societies: The United States, Taiwan, South Korea, and China

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    The current study investigates gender differences in behavioral regulation in four societies: the United States, Taiwan, South Korea, and China. Directly assessed individual behavioral regulation (Head–Toes–Knees–Shoulders, HTKS), teacher-rated classroom behavioral regulation (Child Behavior Rating Scale, CBRS) and a battery of school readiness assessments (mathematics, vocabulary, and early literacy) were used with 814 young children (ages 3–6 years). Results showed that girls in the United States had significantly higher individual behavioral regulation than boys, but there were no significant gender differences in any Asian societies. In contrast, teachers in Taiwan, South Korea, as well as the United States rated girls as significantly higher than boys on classroom behavioral regulation. In addition, for both genders, individual and classroom behavioral regulation were related to many aspects of school readiness in all societies for girls and boys. Universal and culturally specific findings and their implications are discussed

    Sheep Rumen Fermentation Characteristics Affected by Feeding Frequency and Feeding Level When Fed Fresh Forage

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    Feeding frequency and feeding level are two important factors affecting rumen fermentation characteristics, but few studies on these have been conducted on fresh forage. Eight rumen-fistulated sheep were fed either fresh chicory or perennial ryegrass hourly in the first period (d 14 to 21) of the experiment and twice-daily in the second period (d 22 to 27) at 1.3 or 2.2 times the requirement of metabolizable energy for maintenance. When fed hourly, but not twice-daily, rumen fluid pH value was affected by forage species and feeding level. The total concentrations of short-chain fatty acid (SCFA) were similar at both feeding levels when fed chicory hourly, but they were greater at the higher feeding level in comparison with the lower feeding level when fed perennial ryegrass. However, forage species and feeding level did not affect rumen fluid total SCFA concentration when sheep were fed twice-daily. Therefore, rumen fermentation characteristics were affected by forage species, feeding frequency, feeding level and their interactions and the differences in fermentation characteristics were more apparent when feeding was performed hourly rather than twice-daily. This study highlighted the importance of feeding frequency on manipulating sheep ruminal metabolism when fed fresh forage

    Evaluating the effect of body mass index and 25-hydroxy-vitamin D level on basal cell carcinoma using Mendelian randomization

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    Abstract Basal cell carcinoma (BCC) is the most common cancer with a rising incidence among white-skinned individuals. A number of epidemiological studies have suggested that obesity and serum 25-hydroxy-vitamin D (25(OH)D) levels may affect the arising of BCC. To address this, we selected 443 and 96 single nucleotide polymorphisms (SNPs) associated with body mass index (BMI) and serum level of 25(OH)D from large-scale genome-wide association studies (GWAS), respectively. The univariable and multivariable two-sample Mendelian randomization (MR) analyses were conducted with a series of sensitivity analyses to ensure the results were reliable and reproducible. The results of univariable two-sample MR analysis showed that higher BMI was related to lower risk for BCC (Odds ratio(OR) = 0.90; 95% confidence interval (CI),[0.81,0.99]; p = 0.02). In addition, this causal effect of BMI on BCC still remained (OR = 0.88; 95%CI,[− 0.22, − 0.03], p-value = 0.008) after adjusting for 25(OH)D level in the multivariable MR analysis. However, the results suggested that 25(OH)D level was not associated with BCC(OR = 1.02; 95%CI, [0.94,1.09], p-value = 0.67). In conclusion, similar to the conclusions of retrospective observational studies, the MR results indicate that high BMI is an independent protective factor for BCC. Meanwhile, vitamin D levels may not be causally associated with the risk of basal cell carcinoma and increasing vitamin D supplementation is unlikely to reduce the risk

    Investigation of Methane Adsorption in Strained IRMOF-1

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    International audiencehe effect of mechanical deformation of metal–organic frameworks on guest adsorption was investigated via a combination of molecular dynamics and grand-canonical Monte Carlo simulations. The volumetric uptake of methane benefited from compressive IRMOF-1, whereas deformation orientation influenced the gravimetric uptake of methane. The deformation structures of IRMOF-1 enlarged adsorption sites, which could be subsequently occupied by additional methane molecules. However, both the void fraction and internal surface area decreased in strained IRMOF-1. The rapid reduction of IRMOF-1 unit cell volume is due to its shear-collapse deformation mode, which contributed to enhanced volumetric uptake of methane in strained IRMOF-1. Hence, methane uptake in strained IRMOF-1 is expected to yield considerable benefits in engineering application of metal–organic frameworks (MOFs)

    A mathematical model to describe the diurnal pattern of enteric methane emissions from non-lactating dairy cows post-feeding

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    Enteric methane emission is not only a source of energy loss in ruminants, but also a potent contributor to greenhouse gas production. To identify the nature and timing of interventions to reduce methane emissions requires knowledge of temporal kinetics of methane emissions during animal husbandry. Accordingly, a mathematical model was developed to investigate the pattern of enteric methane emissions after feeding in dairy cows. The model facilitated estimation of total enteric methane emissions (V, g) produced by the residual substrate (V1, g) and newly ingested feed (V2, g). The model was fitted to the 10 h methane emission patterns after morning feeding of 16 non-lactating dairy cows with various body weights (BW), and the obtained parameters were used to predict the kinetics of 24 h methane emission for each animal. The rate of methane emission (g/h) reached a maximum within 1 to 2 h after feeding, followed by a gradual post-prandial decline to a basal value before the next feeding. The model satisfactorily fitted curves for each cow according to the criterion of goodness-of-fit, and provided biological descriptions for fluctuations in methane emissions based on basal V1 and feeding V2 in response to the changes in BW and dry matter intake (DMI) of different dairy cows. The basal V1 and feeding V2 are probably maintained by slow- and readily-degradable substrates, respectively. The former contributed at least 0.6 of methane production. In summary, the model provides a means to separate basal V1 and feeding V2 within V, and can be used to predict 24 h emission from a single feeding period

    Clathrin and AP2 are required for phagocytic receptor-mediated apoptotic cell clearance in Caenorhabditis elegans

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    Clathrin and the multi-subunit adaptor protein complex AP2 are central players in clathrin-mediated endocytosis by which the cell selectively internalizes surface materials. Here, we report the essential role of clathrin and AP2 in phagocytosis of apoptotic cells. In Caenorhabditis elegans, depletion of the clathrin heavy chain CHC-1 and individual components of AP2 led to a significant accumulation of germ cell corpses, which resulted from defects in both cell corpse engulfment and phagosome maturation required for corpse removal. CHC-1 and AP2 components associate with phagosomes in an inter-dependent manner. Importantly, we found that the phagocytic receptor CED-1 interacts with the α subunit of AP2, while the CED-6/Gulp adaptor forms a complex with both CHC-1 and the AP2 complex, which likely mediates the rearrangement of the actin cytoskeleton required for cell corpse engulfment triggered by the CED-1 signaling pathway. In addition, CHC-1 and AP2 promote the phagosomal association of LST-4/Snx9/18/33 and DYN-1/dynamin by forming a complex with them, thereby facilitating the maturation of phagosomes necessary for corpse degradation. These findings reveal a non-classical role of clathrin and AP2 and establish them as indispensable regulators in phagocytic receptor-mediated apoptotic cell clearance
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