This study compared the protective effect of sodium selenite (SS) and selenomethionine (SeMet) on heat stress (HS) invoked porcine IPEC-J2 cellular damage and integrate potential roles of corresponding selenoprotein. Cells were cultured at 37 oC until 80% confluence, and then subjected to four different conditions for 24 h: at 37 oC (Control), 41.5 oC (HS), 41.5 oC supplied with 0.42 µmol Se/L SS (SS) or SeMet (SeMet). HS significantly decreased cell viability, up-regulated mRNA and protein levels of HSP70, and down-regulated mRNA and protein levels of tight junction-related proteins (CLDN-1 and ZO-1). HS induced cells injury was associated with the up-regulation (P < 0.05) of 6 inflammation-related genes and 14 selenoprotein encoding genes, and down-regulation (P < 0.05) of 2 inflammation-related genes and 5 selenoprotein encoding genes. Compared with the HS group, SS and SeMet supplementation resulted in an increase (P < 0.05) in cell viability, decreases (P < 0.05) mRNA expression of HSP70 and 6 inflammation-related genes, and rescue (P < 0.05) of mRNA and protein levels of CLDN-1 and ZO-1. SS and SeMet supplementation changes expressions of 19 selenoprotein encoding genes in cells affected by HS. Both Se supplementation significantly recovered the protein level of GPX1 and increased SELP in the IPEC-J2 cells under HS, respectively. In summary, Se supplementation alleviated the negative impact of HS on IPEC-J2 cells, and their cellular protective effect was associates with regulation expression of selenoproteins, SeMet exhibited a better protective effect.

The secondary instabilities of stationary cross-flow vortices in a Mach 6 swept wing flow are studied using Floquet theory. High-frequency secondary instability modes of ‘y’ mode on top of stationary cross-flow vortices, and ‘z’ mode concentrating on the shoulder of the stationary cross-flow vortex are found. The most unstable secondary instability mode is always the ‘z’ mode as in incompressible swept wing flows. A new secondary instability mode concentrating on the trough of the stationary cross-flow vortex is found. The balance analysis of disturbance kinetic energy shows that the new mode belongs to the class of ‘y’ mode. The growth rate of the new ‘y’ mode located on the trough of the stationary cross-flow vortex is significantly larger than that of the ‘y’ mode on top of the stationary cross-flow vortex, and is comparable with the growth rate of the ‘z’ mode. It is also found that the new ‘y’ mode with higher frequency can evolve into the ‘z’ mode further downstream. The role of the pressure fluctuation term, including the pressure diffusion and pressure dilatation, in the energy production of secondary instability modes, is also investigated. It is shown that the pressure diffusion will only enhance the growth rate of the ‘z’ mode with higher frequency, but has little influence on other types of secondary instability mode. However, the pressure dilatation term arising from non-vanishing velocity divergence will reduce the growth rates of all secondary instability modes.

A kind of novel Ni–P gradient coating/stannate conversion film was deposited on AZ91D magnesium alloy (AZ91D alloy) by an integrative method involved stannate conversion and electroless plating. The results indicated that using sodium hypophosphite concentrations varied as 5, 10, 22, 46, and 60 g/L in the bath, the electroless Ni–P gradient coating with typical cell morphologies was successfully prepared, and the structures transited from crystalline → microcrystalline → amorphous were obtained as increasing P content from 3.31 to 12.58 wt%. Furthermore, the corrosion morphologies, polarization curves, and the electrochemical impedance spectroscopy result indicated that the corrosion resistance of AZ91D alloy substrate was significantly improved and the corrosion resistance of Ni–P gradient coating was superior than that of stannate conversion film, which might be attributed to the gradient structure and rising P content with unique function.

Small additions of boron can remarkably improve the long-term creep resistance of 9–12% Cr steels. The improvement has been attributed to boron segregation to grain boundaries during quenching, and subsequent boron incorporation into certain families of precipitates during tempering. However, the detailed mechanisms are not yet fully understood. Atom probe tomography (APT) is an excellent technique for gaining insights into boron distribution, however, in order to acquire accurate analysis of boron in 9–12% Cr steels using APT, there are several key challenges. In order to better understand and address these challenges, we developed a novel method for site-specific APT specimen preparation, which enables convenient preparation of specimens containing specifically selected grain boundaries positioned approximately perpendicular to the axis of the APT tip. Additionally, when analyzing boron at boundaries and in carbides (as diluted solute) and borides, a widening of the profile of boron distribution compared to other elements was repeatedly observed. This phenomenon is particularly analyzed and discussed in light of the evaporation field of different elements. Finally, the possible effects of detector dead-time on quantitative analysis of boron in metal borides are discussed. A simple method using 10B correction was used to obtain good quantification.

In inertial confinement fusion experiments that involve short-laser pulses such as fast ignition (FI), diagnosis of neutrons is usually very challenging because high-intensity γ rays generated by short-laser pulses would mask the much weaker neutron signal. In this paper, fast-response scintillators with low afterglow and gated microchannel plate photomultiplier tubes are combined to build neutron time-of-flight (nTOF) spectrometers for such experiments. Direct-drive implosion experiments of deuterium-gas-filled capsules were performed at the Shenguang-II Upgrade (SG-II-UP) laser facility to study the compressed fuel areal density (〈ρR〉) and evaluate the performance of such nTOF diagnostics. Two newly developed quenched liquid scintillator detectors and a gated ultrafast plastic scintillator detector were used to measure the secondary DT neutrons and primary DD neutrons, respectively. The secondary neutron signals were clearly discriminated from the γ rays from (n, γ) reactions, and the compressed fuel areal density obtained with the yield-ratio method agrees well with the simulations. Additionally, a small scintillator decay tail and a clear DD neutron signal were observed in an integrated FI experiment as a result of the low afterglow of the oxygen-quenched liquid scintillator.

Nanoscale magnetization modulation by electric field enables the construction of low-power spintronic devices for information storage applications and, etc. Electric field-induced ion migration can introduce desired changes in the material's stoichiometry, defect profile, and lattice structure, which in turn provides a versatile and convenient means to modify the materials’ chemical-physical properties at the nanoscale and in situ. In this review, we provide a brief overview on the recent study on nanoscale magnetization modulation driven by electric field-induced migration of ionic species either within the switching material or from external sources. The formation of magnetic conductive filaments that exhibit magnetoresistance behaviors in resistive switching memory via foreign metal ion migration and redox activities is also discussed. Combining the magnetoresistance and quantized conductance switching of the magnetic nanopoint contact structure may provide a future high-performance device for non-von Neumann computing architectures.

The animal gut effectively prevents the entry of hazardous substances and microbes while permitting the transfer of nutrients, such as water, electrolytes, vitamins, proteins, lipids, carbohydrates, minerals and microbial metabolites, which are intimately associated with intestinal homoeostasis. The gut maintains biological functions through its nutrient-sensing receptors, including the Ca-sensing receptor (CaSR), which activates a variety of signalling pathways, depending on cellular context. CaSR coordinates food digestion and nutrient absorption, promotes cell proliferation and differentiation, regulates energy metabolism and immune response, stimulates hormone secretion, mitigates secretory diarrhoea and enhances intestinal barrier function. Thus, CaSR is crucial to the maintenance of gut homoeostasis and protection of intestinal health. In this review, we focused on the emerging roles of CaSR in the modulation of intestinal homoeostasis including related underlying mechanisms. By elucidating the relationship between CaSR and animal gut homoeostasis, effective and inexpensive methods for treating intestinal health imbalance through nutritional manipulation can be developed. This article is expected to provide experimental data of the effects of CaSR on animal or human health.

Markley variables have advantages of slow variation, easy numerical integration and high precision in describing the attitude of spinning spacecraft. Previous attitude estimation methods based on Markley variables for spinning spacecraft usually employ a sun vector from the sun sensor, a magnetic vector from the magnetometer, or the angular rate from the gyro as the measurement. This paper proposes a Markley variables-based attitude estimation method using optical flow and a star vector from a star sensor as the measurement, where optical flow provides rate information and the star vector provides direction information. This method can estimate the direction of the spin axis and spin angular rate very well by using only one star sensor. In addition, the star sensor has higher accuracy than the traditional sun sensor and magnetometer, and the star sensor can also replace the gyro in case the gyro is out of action. The impact factors of this method are also analysed, which include spin angular rate, spin axis orientation and spacecraft moment of inertia tensor error.

Cell's sub-cellular architecture and function can be revealed by Cryo soft X-ray tomography (Cryo-SXT) and Cryo-fluorescence microscopy (Cryo-FM) respectively. To understand the connection between cells' structure and function, correlative Cryo-SXT and Cryo-FM has been applied. Here we introduce a semiautomatic precise alignment and fusion technology of Cryo-SXT and Cryo-fluorescence microscopy.

'Missing wedge' problem exists in some kind of CT imaging situations, such as electron microscopy, x-ray nano-CT image, etc. Method such as iterative reconstruction algorithms, total variation based method were applied to improve the reconstruction quality, but the 'missing wedge' artifacts are still inevitable. In this paper, a method based on image processing technique was proposed to locate the 'missing wedge' artifacts in CT reconstruction. The result showed good performance on locating the artifacts, which also showed the potential in CT reconstruction and image analysis in nano-CT.

The soft X-ray Microscopy beamline BL07W at National Synchrotron Radiation Laboratory is devoted to cryo nano-tomography for biological applications in the water window (284 - 530 eV) and for imaging of nanomaterials from 200 to 2500 eV. An ellipsoidal capillary used as condense to focus monochromatic light onto the sample. Two Ni zone plate (ZP) lenses made by Zeiss with 40 nm and 25 nm outer most zone widths, respectively, are available, giving spatial resolution in 2D of down to 40 nm and 30 nm, respectively. Hydrated biological specimens had been imaged in the water window photon energy range without chemical fixation, dehydration, chemical staining and physical sectioning. In addition, other applications such as nanomaterials imaging had been demonstrated.

We present laboratory measurement and theoretical analysis of silicon K-shell lines in plasmas produced by Shenguang II laser facility, and discuss the application of line ratios to diagnose the electron density and temperature of laser plasmas. Two types of shots were carried out to interpret silicon plasma spectra under two conditions, and the spectra from 6.6 Å to 6.85 Å were measured. The radiative-collisional code based on the flexible atomic code (RCF) is used to identify the lines, and it also well simulates the experimental spectra. Satellite lines, which are populated by dielectron capture and large radiative decay rate, influence the spectrum profile significantly. Because of the blending of lines, the traditional $G$ value and $R$ value are not applicable in diagnosing electron temperature and density of plasma. We take the contribution of satellite lines into the calculation of line ratios of He- $\unicode[STIX]{x1D6FC}$ lines, and discuss their relations with the electron temperature and density.

Mastery of strengthening strategies to achieve high-capacity anodes for lithium-ion batteries can shed light on understanding the nature of diffusion-induced stress and offer an approach to use submicro-sized materials with an ultrahigh capacity for large-scale batteries. Here, we report solute strengthening in a series of silicon (Si)–germanium (Ge) alloys. When the larger solute atom (Ge) is added to the solvent atoms (Si), a compressive stress is generated in the vicinity of Ge atoms. This local stress field interacts with resident dislocations and subsequently impedes their motion to increase the yield stress in the alloys. The addition of Ge into Si substantially improves the capacity retention, particularly in Si0.50Ge0.50, aligning with literature reports that the Si/Ge alloy showed a maximum yield stress in Si0.50Ge0.50. In situ X-ray diffraction studies on the Si0.50Ge0.50 electrode show that the phase change undergoes three subsequent steps during the lithiation process: removal of surface oxide layer, formation of cluster-size Lix(Si,Ge), and formation of crystalline Li15(Si,Ge)4. Furthermore, the lithiation process starts from higher index facets, i.e., (220) and (311), then through the low index facet (111), suggesting the orientation-dependence of the lithiation process in the Si0.50Ge0.50 electrode.

Manipulating the thermal conductivity of solids is important for practical applications. Due to the fact that phonons in thermoelectric materials have longer mean free paths (MFPs) than electrons, strengthening phonon scattering to reduce lattice thermal conductivity (κlat) becomes the most straightforward and effective approach to enhance the thermoelectric figure of merit, ZT, which determines the maximum device efficiency. Phonons have a wide range of MFPs in semiconductors, and different dimensions of lattice defects can be targeted to scatter particular phonons with distinct relaxation times. Designing hierarchical nano-microstructures, spanning from point defects to volume defects, would be beneficial to achieve low κlat via a full spectrum of phonon scattering. Herein, we review the formation and underlying mechanisms for lattice defects and highlight the role of all-scale hierarchical nano-microstructure on phonon engineering. Existing challenges in simulations are also discussed.

Solar steam generation is an efficient and green technology for desalination and drinking water purification, however, impeded by high cost, low efficiency, and complicated process. Black titania is expected to exhibit excellent solar steam performance due to its outstanding light absorption properties, chemical stability, low cost, and innocuity. Herein, we design a high absorbing and efficient solar steam generation system based on a black titania/graphene oxide nanocomposite film affixed to airlaid paper wrapped over the surface of expandable polyethylene foam; the system possesses several important criteria required for the ideal solar steam generator: wide-spectrum absorption, adequate water supply, reduced heat loss for localized water heating, and porous structure for steam flow. Remarkably, we realized a solar thermal conversion efficiency of 69.1% under illumination of 1 kW/m2 without solar concentration, and the device delivered remarkable cycle stability.

In the Venus capture period, it is difficult for celestial autonomous navigation to satisfy the requirement of high precision. To improve autonomous navigation performance, a Direction, Distance and Velocity (DDV) measurements deeply integrated navigation method is proposed. The “deeply” integrated navigation reflects the fact that the direction and velocity measurements suppress the Doppler effects in the pulsar signals. In the pulsar observation period, the direction and velocity measurements are utilised to compensate for Doppler effects in the pulsar signals. By these means, the residual effects can be ignored. When the direction, distance or velocity measurements are obtained, they are fused to improve the navigation performance. Simulation results demonstrate that the DDV measurements deeply integrated navigation filter converges very well, and provides highly accurate position estimation without a high quality requirement on navigation sensors.

The present research focuses on glacier changes in the southeast of the Qinghai–Xizang (Tibetan) Plateau, where most of the temperate glaciers in China are located. Our results show that the 102 measured glaciers in the region have all retreated between 1915 and 1980, with total area and volume decreases of 47.9 km2 and 6.95 km3, respectively. The extrapolated mass loss of all glaciers in the Gangrigabu mountains amounted to 27 km3, 9.8% of the ice mass in 1915. Between 1980 and 2001, glaciers in the region have also experienced a general retreat; however, up to 40% of the glaciers were advancing. Our analysis demonstrates that precipitation in the studied area has increased substantially since the mid-1980s. This precipitation increase is likely to bring about a positive mass balance for glaciers in the region, so that the retreat of retreating glaciers might slow down or even turn into advance. Considering the sensitivity of the temperate glaciers in the region and the uncertainty in climate projections, more attention must be paid to glacier changes in the southeast Tibetan Plateau region.

Glaciers in the Muztag Ata and Konggur mountains of the eastern Pamir plateau, northwestern China, have been monitored by applying aerial photo stereo models (1962/66) and Landsat TM (1990) and ETM+ (1999) images, all of which have been compared in order to detect areal and frontal changes through the past four decades. The mean frontal retreat of glaciers in the Muztag Ata and Konggur mountains increased from 6.0 ma−1 between 1962/66 and 1990 to 11.2ma−1 between 1990 and 1999, with an overall glacier length reduction of 9.9% for the whole study period. The glacier area has decreased by 7.9%, mainly due to changes observed in the most recent period (1990–99), when the annual area loss almost tripled to 1.01 km2 a−1. Based on meteorological data from Taxkogan station since 1957, we conclude that climate change, particularly the rise in summer temperature after 1994, is the main forcing factor in glacier shrinkage.

Recent studies have indicated that widespread wastage of glaciers in western China has occurred since the late 1970s. By using digitized glacier outlines derived from the 1970 inventory and Landsat satellite data from 1990/91 to 2001, we obtained area changes of about 278 glaciers with a total area of 2711.57 km2 in the heavily glaciated west Kunlun Shan (WKS) in the northern Tibetan Plateau (TP). Results indicate that the prevailing characteristic of glacier variation is ice wastage, and glacier area decreased by 10 km2 (0.4% of the total 1970 area) between 1970 and 2001. Both the south and north slopes of the WKS presented shrinkage during 1970–2001, but whereas on the north slope a slight enlargement of ice extent during 1970–90 was followed by a reduction of 0.2% during 1990–2001, on the south slope the glacier area decreased by 1.2% during 1970–91, with a small increment of 0.6% during 1991–2001. Comparisons with other glaciated mountainous regions in western China show that glaciers in the research area have experienced less retreat. Based on records from the Guliya ice core, we believe that an increase in air temperature was the main forcing factor for glacier shrinkage during 1970–2001.