American silk moth, Antheraea polyphemus Cramer 1775 (Lepidoptera: Saturniidae), native to North America, has potential significance in sericulture for food consumption and silk production. To date, the phylogenetic relationship and divergence time of A. polyphemus with its Asian relatives remain unknown. To end these issues, two mitochondrial genomes (mitogenomes) of A. polyphemus from the USA and Canada respectively were determined. The mitogenomes of A. polyphemus from the USA and Canada were 15,346 and 15,345 bp in size, respectively, with only two transitions and five indels. The two mitogenomes both encoded typical mitochondrial 37 genes. No tandem repeat elements were identified in the A+T-rich region of A. polyphemus. The mitogenome-based phylogenetic analyses supported the placement of A. polyphemus within the genus Antheraea, and revealed the presence of two clades for eight Antheraea species used: one included A. polyphemus, A. assamensis Helfer, A. formosana Sonan and the other contained A. mylitta Drury, A. frithi Bouvier, A. yamamai Guérin-Méneville, A. proylei Jolly, and A. pernyi Guérin-Méneville. Mitogenome-based divergence time estimation further suggested that the dispersal of A. polyphemus from Asia into North America might have occurred during the Miocene Epoch (18.18 million years ago) across the Berling land bridge. This study reports the mitogenome of A. polyphemus that provides new insights into the phylogenetic relationship among Antheraea species and the origin of A. polyphemus.

This study presents a novel investigation into the vortex dynamics of flow around a near-wall rectangular cylinder based on direct numerical simulation at $Re=1000$, marking the first in-depth exploration of these phenomena. By varying aspect ratios ($L/D = 5$, $10$, $15$) and gap ratios ($G/D = 0.1$, $0.3$, $0.9$), the study reveals the vortex dynamics influenced by the near-wall effect, considering the incoming laminar boundary layer flow. Both $L/D$ and $G/D$ significantly influence vortex dynamics, leading to behaviours not observed in previous bluff body flows. As $G/D$ increases, the streamwise scale of the upper leading edge (ULE) recirculation grows, delaying flow reattachment. At smaller $G/D$, lower leading edge (LLE) recirculation is suppressed, with upper Kelvin–Helmholtz vortices merging to form the ULE vortex, followed by instability, differing from conventional flow dynamics. Larger $G/D$ promotes the formation of an LLE shear layer. An intriguing finding at $L/D = 5$ and $G/D = 0.1$ is the backward flow of fluid from the downstream region to the upper side of the cylinder. At $G/D = 0.3$, double-trailing-edge vortices emerge for larger $L/D$, with two distinct flow behaviours associated with two interactions between gap flow and wall recirculation. These interactions lead to different multiple flow separations. For $G/D = 0.9$, the secondary vortex (SV) from the plate wall induces the formation of a tertiary vortex from the lower side of the cylinder. Double-SVs are observed at $L/D = 5$. Frequency locking is observed in most cases, but is suppressed at $L/D = 10$ and $G/D = 0.9$, where competing shedding modes lead to two distinct evolutions of the SV.

The numerical investigation focuses on the flow patterns around a rectangular cylinder with three aspect ratios ($L/D=5$, $10$, $15$) at a Reynolds number of $1000$. The study delves into the dynamics of vortices, their associated frequencies, the evolution of the boundary layer and the decay of the wake. Kelvin–Helmholtz (KH) vortices originate from the leading edge (LE) shear layer and transform into hairpin vortices. Specifically, at $L/D=5$, three KH vortices merge into a single LE vortex. However, at $L/D=10$ and $15$, two KH vortices combine to form a LE vortex, with the rapid formation of hairpin vortex packets. A fractional harmonic arises due to feedback from the split LE shear layer moving upstream, triggering interaction with the reverse flow. Trailing edge (TE) vortices shed, creating a Kármán-like street in the wake. The intensity of wake oscillation at $L/D=5$ surpasses that in the other two cases. Boundary layer transition occurs after the saturation of disturbance energy for $L/D=10$ and $15$, but not for $L/D=5$. The low-frequency disturbances are selected to generate streaks inside the boundary layer. The TE vortex shedding induces the formation of a favourable pressure gradient, accelerating the flow and fostering boundary layer relaminarization. The self-similarity of the velocity defect is observed in all three wakes, accompanied by the decay of disturbance energy. Importantly, the decrease in the shedding frequency of LE (TE) vortices significantly contributes to the overall decay of disturbance energy. This comprehensive exploration provides insights into complex flow phenomena and their underlying dynamics.

This study examines family context and sexual debut among young people in China. Using data from the 2018 Panel Study of Chinese University Students (PSCUS), it explores how the family is correlated with sexual debut among young people in China aged 18–24 years. The Kaplan–Meier method was adopted to detect a survival function for different family factors and related demographic variables. Cox proportional hazard regression analysis was adopted to calculate hazard ratios for the timing of sexual debut. The average age of sexual debut among the college students was 18.39 years. The Kaplan–Meier analysis showed that sexual intercourse initiation was earlier for female students who had no siblings, and those who had a mother with senior high school (including technical school) education or higher family income, but this correlation was insignificant among male students. The multivariate hazard regression analysis revealed that living in a family with a higher level of fathers’ education, having a lower level of family income and having siblings had positive correlations with later sexual debut among the college students. Moreover, family factors showed gender differences in their associations with the timing of sexual debut, typically parent’s education level, family income and left-behind experience. This study provides a comprehensive perspective on the role of family influences in timing of sexual debut among youth in China.

The effect of vitamin D (VD) on the risk of preeclampsia (PE) is uncertain. Few of previous studies focused on the relationship between dietary VD intake and PE risk. Therefore, we conducted this 1:1 matched case–control study to explore the association of dietary VD intake and serum VD concentrations with PE risk in Chinese pregnant women. A total of 440 pairs of participants were recruited during March 2016 to June 2019. Dietary information was obtained using a seventy-eight-item semi-quantitative FFQ. Serum concentrations of 25(OH)D2 and 25(OH)D3 were measured by liquid chromatography–tandem MS. Multivariate conditional logistic regression was used to estimate OR and 95 % CI. Restricted cubic splines (RCS) were plotted to evaluate the dose–response relationship of dietary VD intake and serum VD concentrations with PE risk. Compared with the lowest quartile, the OR of the highest quartile were 0·45 (95 % CI 0·29, 0·71, Ptrend = 0·001) for VD dietary intake and 0·26 (95 % CI 0·11, 0·60, Ptrend = 0·003) for serum levels after adjusting for confounders. In addition, the RCS analysis suggested a reverse J-shaped relationship between dietary VD intake and PE risk (P-nonlinearity = 0·02). A similar association was also found between serum concentrations of total 25(OH)D and PE risk (P-nonlinearity = 0·02). In conclusion, this study provides evidence that higher dietary intake and serum levels of VD are associated with the lower risk of PE in Chinese pregnant women.

As part of our ongoing research on Peltigera, we recognize a morphologically and phylogenetically distinct new species, Peltigera shennongjiana L. F. Han & S. Y. Guo, from the Shennongjia region of Central China. It is distinguished from other members of the P. canina-group by the presence of abundant phyllidia and flat, branched lobules along the margin or laminal cracks, short lobes, and a pruinose, usually greyish upper surface. The various populations sampled share identical ITS nr DNA sequences, of which the ITS2 regions are characterized by a unique secondary structure. Furthermore, we provide a detailed comparison of the characteristics of P. shennongjiana with morphologically similar species and a key to Peltigera species reported from China.

The present study was conducted to evaluate the effects of glucose, soya oil or glutamine on jejunal morphology, protein metabolism and protein expression of the mammalian target of rapamycin complex 1 (mTORC1) signalling pathway in jejunal villus or crypt compartment of piglets. Forty-two 21 d-weaned piglets were randomly allotted to one of the three isoenergetic diets formulated with glucose, soya oil or glutamine for 28 d. On day 14 or 28, the proteins in crypt enterocytes were analysed with isobaric tags for relative and absolute quantification and proteins involved in mTORC1 signalling pathway in villus or crypt compartment cells were determined by Western blotting. Our results showed no significant differences (P > 0·05) in jejunal morphology among the three treatments on day 14 or 28. The differentially expressed proteins mainly took part in a few network pathways, including antimicrobial or inflammatory response, cell death and survival, digestive system development and function and carbohydrate metabolism. On day 14 or 28, there were higher protein expression of eukaryotic initiation factor-4E binding protein-1 in jejunal crypt compartment of piglets supplemented with glucose or glutamine compared with soya oil. On day 28, higher protein expression of phosphor-mTOR in crypt compartment was observed in piglets supplemented with glucose compared with the soya oil. In conclusion, the isoenergetic glucose, soya oil or glutamine did not affect the jejunal morphology of piglets; however, they had different effects on the protein metabolism in crypt compartment. Compared with soya oil, glucose or glutamine may be better energy supplies for enterocytes in jejunal crypt compartment.

Underground Nuclear Astrophysics in China (JUNA) will take the advantage of the ultra-low background in Jinping underground lab. High current accelerator with an ECR source and detectors were commissioned. JUNA plans to study directly a number of nuclear reactions important to hydrostatic stellar evolution at their relevant stellar energies. At the first period, JUNA aims at the direct measurements of 25Mg(p,γ)26 Al, 19F(p,α) 16 O, 13C(α, n) 16O and 12C(α,γ) 16O near the Gamow window. The current progress of JUNA will be given.

The ZnO/g-C3N4 binary heterostructures were formed by two steps, then the firm connection between ZnO NRs and lamellar g-C3N4 was characterized through powder XRD, FESEM with EDS, TEM, XPS, and Thermogravimetric analysis. Then the gas sensing performances of ZnO/g-C3N4 nanoheterostructures were analyzed systematically by using ethanol as a molecular probe. The results revealed that the fabricated compositive sensor not only exhibited quick response/recovery characteristics in the whole operating temperature (OT) range of 200–300 °C but also got a maximum response of 14.29 toward 100 ppm of ethanol at the optimal OT of only 260 °C. Moreover, such heterostructures also demonstrated good selectivity and superb reproducibility to acetone among all the tested toxic gases, especially higher response and faster response–recovery speeds than the pristine ZnO sensor. The above ZnO/g-C3N4 heterostructures may also supply other novel applications in the aspects of lithium-ion batteries, photocatalysis, optical devices, and so on.

Since 2010, Jankowski’s Bunting Emberiza jankowskii has been listed as ‘Endangered’ on the IUCN Red List of Threatened Species. However, because no comprehensive surveys had been conducted, it was not known whether undiscovered populations existed elsewhere, so the population status of the species could not be assessed accurately. The aim of this study was to assess the breeding distribution and population size of Jankowski’s Bunting in China. Fifty sites in Inner Mongolia, and Jilin, Heilongjiang, Liaoning and Hebei Provinces were surveyed to locate suitable habitat and breeding populations of Jankowski’s Bunting. The surveyed sites included historical breeding distribution areas, wintering sites, and regions adjacent to historical breeding distribution areas. We confirmed that Jankowski’s Bunting has disappeared from most of its former breeding distributions, with the exceptions of Dagang, Xiergen and Tumiji. Additionally, 13 new breeding sites were discovered in Inner Mongolia. All currently known populations breed in Mongolian steppe-vegetation zones, with shrubs dominated by the natural Siberian apricot Prunus sibirica, indicating that this type of habitat is crucial for the survival of the species. Based on remote sensing, the suitable breeding habitat for Jankowski’s Bunting is estimated to be approximately 280 km2. The population size of Jankowski’s Bunting could range between 9,800 and 12,500 individuals, which is much higher than the numbers estimated in previous reports that were based on partial surveys. The suitable habitat remaining in Inner Mongolia would highly benefit from the implementation of the National Key Public Forest Protection Project. The population size of Jankowski’s Bunting is larger than previously estimated, but it is still threatened by habitat degradation and fragmentation, and our survey results reinforce the need for more research. The status of Jankowski’s Bunting in China still meets the IUCN criteria B2ab for an ‘Endangered’ species.

Recent studies have shown that chemical immiscibility is important to achieve enhanced radiation tolerance in metallic multilayers as immiscible layer interfaces are more stable against radiation induced mixing than miscible interfaces. However, as most of these immiscible systems have incoherent interfaces, the influence of coherency on radiation resistance of immiscible systems remains poorly understood. Here, we report on radiation response of immiscible Cu/Fe multilayers, with individual layer thickness h varying from 0.75 to 100 nm, subjected to He ion irradiation. When interface is incoherent, the peak bubble density decreases with decreasing h and reaches a minimum when h is 5 nm. At even smaller h when interface is increasingly coherent, the peak bubble density increases again. However, void swelling in coherent multilayers with smaller h remains less than those in incoherent multilayers. Our study suggests that the coherent immiscible interface is also effective to alleviate radiation induced damage.

Si-rich oxide/SiO2 multilayer films with different N2O flow rates have been deposited by plasma enhanced chemical vapor deposition technique, and Si quantum dot (Si-QD)/SiO2 multilayer films are obtained by 1100 °C annealing. Steady photoluminescence (PL) spectra show that the main optical emission mechanism changes from quantum confinement effect of Si-QDs to interface defect states with increasing the flow rate of N2O. Curve fittings of time-resolved PL spectra show that two log-normal decay time distribution bands are obtained, and both the most frequent life-times decrease with increasing the flow rate of N2O, while increase with the red shift of detecting wavelength. Analyses indicate that defect states density and size distribution of Si-QDs strongly influence the PL decay properties.

The terricolous lichen Peltigera wulingensis sp. nov. is described from Wuling Mountain, North China. It can be distinguished from other members of the P. rufescens group by its phyllidia along the margin or laminal cracks, scabrose upper surface, lobe extremities with tufts of tiny grey-whitish to pale brown hairs, and its slender, scattered and simple rhizines. Comparisons of the ITS sequences of the nuclear ribosomal DNA repeat tandem support the taxonomic distinctness of this species.

In this paper, the ion jet generation from the interaction of an ultraintense laser pulse and a rear-side concave target is investigated analytically using a simple fluid model. We find that the ion expanding surface at the rear-side is distorted due to a strong charge-separation field, and that this distortion becomes dramatic with a singular cusp shown on the central axis at a critical time. The variation of the transverse ion velocity and the relative ion density diverge on the cusp, signaling the emergence of an on-axis ion jet. We have obtained analytical expressions for the critical time and the maximum velocity of the ion jet, and suggested an optimum shape for generating a collimated energetic ion jet. The above theoretical analysis has been verified by particle-in-cell (PIC) numerical simulations.

The Rockwell indentation test was used to generate interface delamination in an EB-PVD thermal barrier coating (TBC) system that was thermally cycled between 300 °C and 1050 °C. Luminescence spectroscopy was applied to measure the thermally grown oxide (TGO) stresses in indentation-affected and perfectly bonded regions. Comparison between experimental stress mapping in bonded and delaminated regions by luminescence spectroscopy and finite element analysis was shown and the effect of delamination paths was presented. Zigzag delamination paths alternating between the top TBC-TGO interface and TGO-bond coat interface were shown to induce TGO stress releases and fluctuations in the delaminated region. Luminescence spectroscopy measurements successfully detect such behavior, making it possible to identify nondestructively the size of the delaminated region, the delamination crack front position, and the delamination paths in part.

Amplified fragment length polymorphism (AFLP) markers linked to the stem nematode resistance gene were developed in sweet potato (Ipomoea batatas (L.) Lam.). Using bulked segregant analysis (BSA), 800 AFLP primer combinations were screened in the resistant and susceptible bulked DNA from the 186 progeny of an F1 single-cross population of Xu781 (resistant parent)×Xushu18 (susceptible parent), and 245 of these AFLP primers showed polymorphic bands between resistant and susceptible DNA. Primer combinations detecting polymorphism between the two bulks were used to screen the parents and eight individuals from each of the bulks. The results showed that E2M23 and E33M20 produced a specific band of about 500 bp and 200 bp in length, respectively, in the resistant plants but not in the susceptible plants, suggesting that the markers named E2M23500 and E33M20200 linked to a gene for stem nematode resistance. Amplified analysis of the 186 F1 individuals indicated that the genetic distance between these two markers and the stem nematode resistance gene was 6.9 cM and 11.1 cM, respectively, measured with Mapmaker 3.0. These two AFLP markers were used to identify ten sweet potato varieties planted widely in China and the results were consistent with those of conventional resistance identification, indicating that the two markers can be used in molecular marker-assisted breeding for stem nematode resistance in the sweet potato.

5-AZA-2′-deoxycytidine (5-AZA-CdR) is a demethylating, teratogenic agent and a mutagen, which causes defects in the developing mouse and rat after implantation. Our previous data indicated that 5-AZA-CdR (0.2 and 1.0 μM) inhibited the development of mouse preimplantation embryos. Pronuclear embryos exposed to 5-AZA-CdR at the pronuclear stage were unable to form 8-cell embryos, while 2-cell-stage embryos exposed to 5-AZA-CdR only developed into uncompacted 8-cell-stage embryos. And there was no formation of blastocysts when 4-cell embryos cultured in 5-AZA-CdR. In our present study, we detected Dnmt1o protein and some developmental gene expression in order to find the reasons for the developmental arrest. Dnmt1o could not traffic to 8-cell nuclei as control when embryos were exposed to 5-AZA-CdR. Dnmt1o was in cytoplasm at 2-cell and 4-cell stages before and after treated with 5-AZA-CdR. Gene expression changes were also detected in this research. Our data indicated that connexin 31 (Cx31), connexin 43 (Cx43), connexin 45 (Cx45), E-cadherin (Cdh1) and β-catenin (Ctnnb1) were all downregulated by 5-AZA-CdR. Cx31, Cx43 and Cx45 are members of connexins family, which have a central role in gap junctions. Cdh1 and Ctnnb1 are necessary for the foundation of tight junctions. Therefore, developmental arrest induced by 5-AZA-CdR may be caused by the failure of Dnmt1o cytoplasmic–nuclear traffic and the down-regulation of developmental gene expression. Normal compaction and blastocoel cavitation need Dnmt1o traffic to 8-cell nuclei and the right gene expression, especially the correlative genes in gap junctions and tight junctions.

We selected 133 solar microwave bursts (SMBs) recorded by SGD and 133 CMEs observed by SOHO/LASCO from November 1999 through September 2003. These SMBs are associated with CMEs and flares. We analyzed the characteristics of the SMBs, including duration, flux peak, burst type, and spectral index. Correlated events were distinguished by time and the location of flare associated with the SMB. We find that (1)The duration of SMBs associated with narrow(0°<width<20°)/normal CMEs(20°<width<120°) or slow CMEs is below 40 minutes. (2)The duration of SMBs associated with Halo-like CMEs(120°<width<360°) or fast CMEs is from several minutes to 200 minutes. (3)The flux peak of SMBs associated with narrow CMEs/normal CMEs or slow CMEs is below 400sfu. (4)The flux peak of SMBs associated with Halo-like CMEs or fast CMEs is from several sfu to several thousands sfu. (5)the majority of SMBs,which are associated with Full Halo CMEs, are Complex/GB bursts. The majority of SMBs, which are associated with narrow CMEs/normal CMEs, are simple bursts. (6)U-shape spectra are observed. The spectra of SMB associated with CME is very flat when f>fmax. A statistical result suggest that CME/flares and SMBs is probably a different manifestation of the same physical process. CME/flare and SMB have intrinsically a physical relationship.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html