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Designing next-generation light-harvesting devices requires a detailed understanding of the transport of photoexcited charge carriers. The record-breaking efficiencies of metal halide perovskite solar cells have been linked to effective charge-carrier diffusion, yet the exact nature of charge-carrier out-of-plane transport remains notoriously difficult to explain. The characteristic spatial inhomogeneity of perovskite films with nanograins and crystallographic disorder calls for the simultaneous and hitherto elusive in situ resolution of the chemical composition, the structural phase and the ultrafast dynamics of the local out-of-plane transport. Here we simultaneously probe the intrinsic out-of-plane charge-carrier diffusion and the nanoscale morphology by pushing depth-sensitive terahertz near-field nanospectroscopy to extreme subcycle timescales. In films of the organic–inorganic metal halide perovskite FA0.83Cs0.17Pb(I1−xClx)3(where FA is formamidinium), domains of the cubic α-phase are clearly distinguished from the trigonal δ-phase and PbI2nano-islands. By analysing deep-subcycle time shifts of the scattered terahertz waveform after photoexcitation, we access the vertical charge-carrier dynamics within single grains. At all of the measured locations, despite topographic irregularities, diffusion is surprisingly homogeneous on the 100 nm scale, although it varies between mesoscopic regions. Linking in situ carrier transport with nanoscale morphology and chemical composition could introduce a paradigm shift for the analysis and optimization of next-generation optoelectronics that are based on nanocrystalline materials.

KM2A is one of the main sub-arrays of LHAASO, working on gamma ray astronomy and cosmic ray physics at energies above 10 TeV. Detector simulation is the important foundation for estimating detector performance and data analysis. It is a big challenge to simulate the KM2A detector in the framework of Geant4 due to the need to track numerous photons from a large number of detector units (>6000) with large altitude difference (30 m) and huge coverage (1.3 km2). In this paper, the design of the KM2A simulation code G4KM2A based on Geant4 is introduced. The process of G4KM2A is optimized mainly in memory consumption to avoid memory overflow. Some simplifications are used to significantly speed up the execution of G4KM2A. The running time is reduced by at least 30 times compared to full detector simulation. The particle distributions and the core/angle resolution comparison between simulation and experimental data of the full KM2A array are also presented, which show good agreement.

Vertical instability (VI) is one of the main challenges for fusion energy realization through advanced tokamak. The disruption caused by VI is known as vertical displacement event (VDE). VDE not only causes serious thermal load to the plasma-facing components but also generates huge mechanical load to the first wall. VI growth rate is a crucial parameter not only for VI identification but also for active control of vertical displacement. In this work, the multilayer perceptron (MLP) model is employed to estimate the plasma VI growth rate ( $\gamma $ ) of the experimental advanced superconducting tokamak (EAST). This model shows great advantages in calculation speed compared with the conventional way of solving rigid plasma response model equations. In this model, 38 magnetic probe measurements divided by plasma current ( $I_{p}$ ) for normalization are taken as input features. Meanwhile, the neural network was trained by taking plasma equilibrium parameters as input features for comparison. The results demonstrate a slightly lower prediction accuracy than the original model. The mean absolute error (MAE) increased from 1.02 to 1.68 $\text{s}^{-1}$ , and the mean square error (MSE) increased from 1.89 to 10.03 $\text{s}^{-2}$ . Finally, issues related to the interpretability of neural networks are discussed.

ABSTRACT This experimental study explores the deformation characterizations of granular material in dense assembly subjected to shearing. The 3D printed elliptical particles with eccentricity of 0.2 were used to simulate [...]

Purpose: Anaplastic thyroid cancer (ATC) is a rare and lethal malignant cancer. In recent years, the application of molecular-driven targeted therapy and immunotherapy has markedly improved the prognosis of ATC. This study aimed to identify characteristic genes for ATC diagnosis and revealed the role of ATC characteristic genes in drug sensitivity and immune cell infiltration. Methods: We downloaded ATC RNA-sequencing data from the GEO database. Following the combination and normalization of the dataset, we first divided the combined datasets into the training cohort and the validation cohort. We identified differentially expressed genes (DEGs) in ATC by differential expression analysis in the training cohort. We used two machine learning algorithms, least absolute shrinkage and selection operator (LASSO) and support vector machine-recursive feature elimination (SVM-RFE) to identify ATC characteristic genes. The CIBERSORT algorithm was performed to calculate the abundance of various immune cells in ATC. Finally, we validated the expression of ATC characteristic genes by quantitative RT-PCR (RT-qPCR) in ATC cell lines and immunohistochemistry (IHC). Results: A total of 425 DEGs were identified in the training cohort, including 240 upregulated genes and 185 downregulated genes. Four ATC characteristic genes (ADM, PXDN, MMP1, and TFF3) were identified, and their diagnostic value was validated in the validation cohort (AUC in ROC analysis > 0.75). We established a practical gene expression-based nomogram to accurately predict the probability of ATC. We also found that ATC characteristic biomarkers are associated with the tumor immune microenvironment and drug sensitivity. Conclusion: ADM, PXDN, MMP1, and TFF3might serve as potential ATC diagnostic biomarkers and may be helpful for ATC molecular targeted therapy and immunotherapy.

X-ray bursts are among the brightest stellar objects frequently observed in the sky by space-based telescopes. A type-I X-ray burst is understood as a violent thermonuclear explosion on the surface of a neutron star, accreting matter from a companion star in a binary system. The bursts are powered by a nuclear reaction sequence known as the rapid proton capture process (rp process), which involves hundreds of exotic neutron-deficient nuclides. At so-called waiting-point nuclides, the process stalls until a slower β+decay enables a bypass. One of the handful of rp process waiting-point nuclides is 64Ge, which plays a decisive role in matter flow and therefore the produced X-ray flux. Here we report precision measurements of the masses of 63Ge, 64,65As and 66,67Se—the relevant nuclear masses around the waiting-point 64Ge—and use them as inputs for X-ray burst model calculations. We obtain the X-ray burst light curve to constrain the neutron-star compactness, and suggest that the distance to the X-ray burster GS 1826–24 needs to be increased by about 6.5% to match astronomical observations. The nucleosynthesis results affect the thermal structure of accreting neutron stars, which will subsequently modify the calculations of associated observables.

ABSTRACT From studies of the chloride penetration behaviour in laboratory tests and real structures, a clear time dependency of the chloride diffusion coefficient is observed. In order to get insight [...]

In critical care patients, acute diaphragm inactivity due to mechanical ventilation (MV) initiates a process of diaphragmatic dysfunction and atrophy referred to as ventilator-induced diaphragm dysfunction (VIDD). Although mitochondrial dysfunction linked to oxidative stress plays a critical role in VIDD, the precise molecular mechanism remains poorly understood. Herein, we show, that six hours of MV resulted in a mitochondrial fission process with reduction of mitochondria size and interaction associated with increase dynamin related protein 1 (DRP1) expression; this was prevented by P110, a molecule that blocks the recruitment of DRP1 to the mitochondrial membrane. Moreover, isolated mitochondria from MV diaphragms exhibited decreased oxygen consumption and an increase of ROS production. These mitochondrial alterations were associated with a rapid oxidation of type 1 ryanodine receptor (RyR1) as well as a depletion of the stabilizing subunit calstabin 1. Subsequently, we observed that the sarcoplasmic reticulum (SR) from the MV diaphragms was leaky to Ca2+and was associated with reduced diaphragmatic contractile function. All of these changes were prevented by the mitochondrial fission inhibitor molecule P110. Taken together, the results from our study show that MV induces mitochondrial fragmentation and dysfunction in the diaphragm that is associated with an up/down regulation of 320 proteins evaluated by global quantitative proteomics analysis, mainly related to mitochondrial function. These results emphasize the importance of molecules targeting mitochondrial fission/fusion balance to prevent VIDD in humans (Fig. 1).

Introduction: One of main scientific goals of the Large High Altitude Air Shower Observatory (LHAASO) is to accurately measure the energy spectra of different cosmic ray compositions around the ‘knee’ region. The Wide Field-of-View (FoV) Cherenkov Telescope Array (WFCTA), which is one of the main detectors of LHAASO and has 18 telescopes, is built to achieve this goal. Multiple telescopes are put together and point to connected directions for a larger FoV. Method: Telescopes are deployed spatially as close as possible, but due to their own size, the distance between two adjacent telescopes is about 10 m. Therefore, the Cherenkov lateral distribution and the parallax between the two telescopes should be considered in the event building process for images crossing over the boundaries of FoVs of the telescopes. An event building method for Cherenkov images measured by multiple telescopes of WFCTA is developed. The performance of the shower measurements using the combined images is evaluated by comparing with showers that are fully contained by a virtual telescope in simulation. Results and conclusion: It is proved that the developed event building process can help to increase the FoV of WFCTA by 30% while maintaining the same reconstruction quality, compared to the separate telescope reconstruction method.

Purpose: Observation of high energy and very high emission from Gamma Ray Bursts (GRBs) is crucial to study the gigantic explosion and the underline processes. With a large field-of-view and almost full duty cycle, the Water Cherenkov Detector Array (WCDA), a sub-array of the Large High Altitude Air Shower Observatory (LHAASO), is appropriate to monitor the very high energy emission from unpredictable transients such as GRBs. Method: Nevertheless, the main issue for an extensive air shower array is the high energy threshold which limits the horizon of the detector. To address this issue a new trigger method is developed in this article to lower the energy threshold of  WCDA for GRB observation. Result: The proposed method significantly improves the detection efficiency of WCDA for gamma-rays around the GRB direction at 10-300 GeV. The sensitivity of the WCDA for GRB detection with the new trigger method is estimated. The achieved sensitivity of the quarter WCDA array above 10 GeV is comparable with that of Fermi-LAT. The data analysis process and corresponding fluence upper limit for GRB 190719C is presented as an example.

The extension of the cosmic-ray spectrum beyond 1 petaelectronvolt (PeV; 1015electronvolts) indicates the existence of the so-called PeVatrons—cosmic-ray factories that accelerate particles to PeV energies. We need to locate and identify such objects to find the origin of Galactic cosmic rays1. The principal signature of both electron and proton PeVatrons is ultrahigh-energy (exceeding 100 TeV) γ radiation. Evidence of the presence of a proton PeVatron has been found in the Galactic Centre, according to the detection of a hard-spectrum radiation extending to 0.04 PeV (ref. 2). Although γ-rays with energies slightly higher than 0.1 PeV have been reported from a few objects in the Galactic plane3–6, unbiased identification and in-depth exploration of PeVatrons requires detection of γ-rays with energies well above 0.1 PeV. Here we report the detection of more than 530 photons at energies above 100 teraelectronvolts and up to 1.4 PeV from 12 ultrahigh-energy γ-ray sources with a statistical significance greater than seven standard deviations. Despite having several potential counterparts in their proximity, including pulsar wind nebulae, supernova remnants and star-forming regions, the PeVatrons responsible for the ultrahigh-energy γ-rays have not yet been firmly localized and identified (except for the Crab Nebula), leaving open the origin of these extreme accelerators.

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Purpose: The main scientific goal of LHAASO-WCDA is to survey gamma-ray sources with energy from 100 GeV to 30 TeV. To observe high-energy shower events, especially to measure the energy spectrum of cosmic rays from 100 TeV to 10 PeV, a dynamic range extension system (WCDA++) is designed to use a 1.5-inch PMT with a dynamic range of four orders of magnitude for each cell in WCDA-1. Method: The dynamic range is extended by using these PMTs to measure the effective charge density in the core region of air shower events, which is an important parameter for identifying the composition of primary particles. Result and Conclusion: The system has been running for more than one year. In this paper, the details of the design and performance of WCDA++ are presented.

Mitochondrial DNA (mtDNA) mutations have long been proposed to play important roles in the pathogenesis of diabetes mellitus (DM). A large proportion of these mutations are localized at the mt-tRNAgenes. Owing to its high mutation rate, a growing number of mt-tRNA mutations have been reported; however some of them are neutral genetic polymorphisms and will not result in the alteration of the mitochondrial function responsible for DM. In this study, we reassessed a recent reported “pathogenic” mutation, tRNAGlyT10003C, in a clinical manifestation of DM. We first performed the conservation assessment of this mutation between different species. Moreover, the bioinformatics analysis was used to predict the secondary structure of mt-tRNAGlyin wild type version and the mutant carrying the T10003C mutation. We also screened the presence of the T10003C mutation in 500 unrelated DM patients and 300 healthy controls. We noticed that the T10003C mutation was not very conserved and did not cause the secondary structure change of mt-tRNAGly. Moreover, this mutation was absent in the 500 unrelated DM patients and controls, suggesting that this mutation may be a rare event in the human population. In conclusion, the current study showed no association between the T10003C mutation and DM in humans.

To limit global warming, governments and industries are engaged in reducing emissions of CO2. There is increasing evidence, however, that it may be necessary to go a step further by removing CO2already emitted. For the purpose of carbon dioxide removal (CDR), a number of negative emissions technologies (NET) have been proposed. These generally make extensive usage of land, energy and water – if they are to be implemented at the large scales needed. It is therefore important to seek, investigate and compare alternative approaches to NET. Desalination plants, though normally seen as sources rather than sinks of CO2, could be modified to provide a new type of NET. In this study, we propose treating desalination reject brine by electrolysis to form Mg(OH)2and thus absorb CO2viathe oceans. The energy and water penalties associated with the electrolysis are calculated as 1.8 GJ per tCO2and 13.7 m3per tCO2respectively, making it an interesting option in comparison with some other types of NET. However, NET-modification more than doubles the specific energy consumption of a reverse-osmosis desalination plant. It is concluded that NET-desalination has potential to contribute to CDR in arid countries (especially if solar energy is used) thus helping to meet Intended Nationally Determined Contributions (INDCs) following the COP21 summit.

Clinical evidence suggests that mood and behavioral symptoms in premenstrual dysphoric disorder (PMDD), a common, recently recognized, psychiatric condition among women, reflect abnormal responsivity to ovarian steroids. This differential sensitivity could be due to an unrecognized aspect of hormonal signaling or a difference in cellular response. In this study, lymphoblastoid cell line cultures (LCLs) from women with PMDD and asymptomatic controls were compared via whole-transcriptome sequencing (RNA-seq) during untreated (ovarian steroid-free) conditions and following hormone treatment. The women with PMDD manifested ovarian steroid-triggered behavioral sensitivity during a hormone suppression and addback clinical trial, and controls did not, leading us to hypothesize that women with PMDD might differ in their cellular response to ovarian steroids. In untreated LCLs, our results overall suggest a divergence between mRNA (for example, gene transcription) and protein (for example, RNA translation in proteins) for the same genes. Pathway analysis of the LCL transcriptome revealed, among others, over-expression of ESC/E(Z) complex genes (an ovarian steroid-regulated gene silencing complex) in untreated LCLs from women with PMDD, with more than half of these genes over-expressed as compared with the controls, and with significant effects for MTF2, PHF19and SIRT1(P<0.05). RNA and protein expression of the 13 ESC/E(Z) complex genes were individually quantitated. This pattern of increased ESC/E(Z) mRNA expression was confirmed in a larger cohort by qRT-PCR. In contrast, protein expression of ESC/E(Z) genes was decreased in untreated PMDD LCLs with MTF2, PHF19 and SIRT1 all significantly decreased (P<0.05). Finally, mRNA expression of several ESC/E(Z) complex genes were increased by progesterone in controls only, and decreased by estradiol in PMDD LCLs. These findings demonstrate that LCLs from women with PMDD manifest a cellular difference in ESC/E(Z) complex function both in the untreated condition and in response to ovarian hormones. Dysregulation of ESC/E(Z) complex function could contribute to PMDD.

Graves’ disease (GD) is an autoimmune thyroid disease, and the most important characteristic of it is the presence of the thyroid-stimulating antibody (TSAb). The mechanisms of the TSAb elevation are still uncertain. Recent studies have suggested that the dysregulation of regulatory T cell (Treg) and T helper 17 (Th17) might stimulate the production of TSAb and be a pathogenesis of GD. However, the role of Treg and Th17 cells in the pathogenesis of GD is still debated. Our aim is to assess changes of Treg and Th17 cells in the spleen of a mouse in an in vivo GD model and try to explain the pathogenesis of GD. We used an adenovirus expressing the autoantigen thyroid-stimulating hormone receptor (Ad-TSHR289) to immunise mice in order to induce GD in the model. Flow cytometry was used to measure the frequencies of splenic Treg and Th17 cells and real-time PCR to analyse the mRNA expression of forkhead box P3(Foxp3) and interleukin-17(IL-17). Compared with the Ad-Control group, the frequencies of CD4+CD25+Foxp3+Treg cells were significantly decreased (p= 0.007) and gene expression of Foxp3 was down-regulated (p= 0.001) in the Ad-TSHR289 group. Though there was no significant difference in CD4+IL-17+T cell subpopulation between the two groups (p= 0.336), the IL-17 mRNA expression was significantly up-regulated in the Ad-TSHR289 group (p= 0.001). The pathogenesis of GD may be associated with reduced Treg cells and increased IL-17 gene expression. The increased IL-17 mRNA needs to be explained by other mechanisms but not Th17 cells.

This study presented the details of a specially designed biaxial testing system with a flexible boundary to examine the features of particle motion and associated contact movement during shearing. The whole testing system was modified from a CKC triaxial testing system so that the production cost was low, and this approach was applicable to other types of triaxial testing systems. The 3D printing technique was applied to ease manufacture of the testing device and to improve the resolution of the subsequent image analyses. The middle part of the biaxial cell was printed using the 3D printer because it is often difficult to make by the traditional means due to a complicated geometry and the requirement for a one-piece material to ensure the cell is seamless and leak-proof. A packing of elliptical rods, also produced by the 3D printer, is used as the test sample. In principle, any shape of particle with designed properties can be printed. The goal of tracing the particle motion and movement at contacts during shearing is achieved by means of particle image velocimetry (PIV) and close-range photogrammetry, based on the reference dots marked on the observation windows of the biaxial cell and two object dots printed on each rod. The high-resolution 3D printer ensured the accuracy of marking the object dots on the rod and therefore improved the resolution of subsequent analyses. The experimental results demonstrated the validity of the biaxial testing system and the ability and effectiveness of the system to capture the kinematic features of particles and associated contact movements in response to biaxial shearing.

Maritime Unmanned Vehicle (MUV) as Unmanned Surface Vehicle is introduced as a novel traffic device for continuous maritime traffic information collection and complementing existing methods for Electronic Patrol System (EPS). MUV cruise path planning is studied regarding maximum sailing time, which is aiming at completing MUVs cruise task on a certain number of the areas with relatively high risk needed surveillance. With detailed description of MUV cruise path planning problem, it is Abstracted as travel salesman problem solved by ant colony algorithm in this paper. The approach used to select cruise objects is proposed, especially the cloud model applied to choose cruise navigation segments. The factors including total cruise distance and standard deviation of cruise time, and K-means clustering method are used to evaluate and handle the scenario with MUV navigation constraint. On the basis of above operations, the special scenario is finally converted into several ones without constraint. At last, the cases of Fuzhou Maritime Safety Administration areas are demonstrated. The results indicate that the method proposed for MUV cruise path planning is feasible and effective.

We report the discovery of a pair of Seyfert galaxies identified in the ROSAT bright source, 1RXS J000306.3-041932. The two Seyferts have the same redshift of 0.106. The angular distance between them is ${\sim}23\arcsec$, corresponding to a projected separation of ${\sim}73$kpc, and suggesting an interacting system. We argue, from its weak IR emission and relatively large nuclear separation, that the system is an example of the interaction between AGNs, rather than interaction-triggered AGN activity.

There are many variations of differential phase contrast imaging methods. Although these imaging methods are different in configuration, they are alike in imaging by extracting differential phase information through the evaluation of the refraction angles. In this paper, we investigate common characteristics shared by various different differential phase contrast imaging methods.

AbstractThe switching frequency of high-power medium-voltage electronic devices is usually kept low to restrain the switching losses. Owing to the low switching frequency, the harmonic current components of the stator were increased, which would also result in difficulties in balancing the neutral point potential. Extracting the fundamental content by low-pass filter produced a signal delay and amplitude attenuation, which could not meet system requirements of high performance control. In this paper, a novel hybrid fundamental stator current observer at different coordinates for the electrically excited synchronous motors was designed based on the observer theory and the complex matrix model. This kind of hybrid observer could extract the fundamental component of the stator current instantaneously, and obtain a relative nice robustness with the variation of the speeds and parameters mismatching. Taking the observed the stator current as the feedback signal, a balance have been obtained for the neutral point potential with a three-level inverter topology. The MATLAB simulation and digital signal processor experimental results verify the availability of the novel hybrid current observer.

Nanocrystalline Cu90Nb10 alloy was produced by high energy ball milling mechanical alloying (MA). The effects of ball milling time on the microstructure and mechanical property of this alloy in the process of MA were investigated. The results show: up to 10 at.% Nb could be dissolved into Cu matrix by MA; the powder particles became compacted and homogeneous with increasing the ball milling time, and the deformation degree also increased synchronously; the grain size of this alloy was refined gradually, and it reached the minimum value of 11.5 nm after 30h milling; the microhardness of this alloy increased with increasing the milling time, and it obtained the maximum value of 328 Hv after 30h milling. The obvious reinforcement of this alloy may be due to the comprehensive effects of the fine grain strengthening, the solid solution strengthening and the strain strengthening.

Nanostructured Cu90Al10 alloy powders were prepared by high energy ball milling mechanical alloying (MA). Up to 10 at.% Al could be dissolved into copper by mechanical alloying at room temperature. Effects of milling time on phase transformation, structural characteristics, and mechanical property of powders were investigated by using X-ray diffraction (XRD), Optical Microscopy (OM) and microhardness tester. The results show: with increasing the milling time, the powder particle size increased gradually, and then it tended to be homogeneous. The grain size of the alloy decreased gradually, but the yield strength increased with the extension of the ball milling. After 30h milling, the grain size reached the minimum value of 9 nm, and the yield strength obtained the maximum value of 511 MPa.

Cu90Zr10 alloy powder was prepared by high-energy ball milling. The microstructure and property evolution of this alloy powder during mechanical alloying (MA) were investigated by using X-ray diffraction and optical microscopy (OM). The alloy powder with an average grain size of 10 - 40 nm was obtained, and the grain size was found to decrease gradually with increasing milling time. The microhardness reached a maximum value (about 295 Hv) after 30 h milling. The internal microstrain and the microhardness of the samples increased due to the grain refinement and solid solution during milling, and 10at.% Zr could be brought into Cu lattice by solid solution during MA. At last, the mechanisms of strengthening were discussed.

Melt strength of polylactic acid (PLA) was improved through various modifications including grafting, crosslinking, chain extension, blending, plasticizing and nucleation. The results showed that melt strength was increased, to varying degrees, by crosslinking, chain extension and blending. In addition, melt strain (detected by velocity) was increased by chain extension, blending with elastomer, and plasticizing, but was decreased by crosslinking. The molecular weights, thermal properties and viscosity of the modified PLAs were also studied to investigate the causes of the observed variations in melt strength. Viscosity results generally corresponded with that of melt strength, but not with that of melt strain. With the exception of plasticizing and nucleation, the modifications had no significant effect on the thermal properties of PLA. The molecular weight (in particular the extremely large molecules representing by Mz) and the polydispersity of PLA were significantly increased after crosslinking and chain extension, which accounts for the observed increase in melt strength.

The telomeric region of repetitive DNA sequences at the end of chromosomes prevents end-to-end fusion of chromosome terminals and deterioration of the doublestrand free ends. Because of the ‘end-replication problem’, telomeres shorten with each round of cell division, resulting in cell senescence. The enzyme telomerase compensates for telomere shortening by elongating telomeric sequences, thereby prolonging the lifespan of the cell. Studies of articular cartilage and bone tissues have indicated that telomere shortening limits normal cell function and proliferation, while the telomere maintenance mechanisms of osteosarcoma cells facilitate escape from cell death and promote immortality. This article reviews the literature on this topic and provides an extensive discussion of the basic molecular biology and roles of telomeres and telomerase in musculoskeletal diseases such as osteoarthritis, osteoporosis and osteosarcoma. Findings to date suggest that telomeres and telomerase may become novel therapeutic targets for the diagnosis, treatment and prevention of musculoskeletal disorders.

Hepatocyte transplantation is regarded as a promising option to correct hereditary metabolic liver disease. This study describes a novel method involving regional transient portal ischemia (RTPI) in combination with hepatic irradiation (IR) as a preparative regimen for hepatocyte transplantation. The right lobules of rat livers (45% of liver mass) were subjected to RTPI of 30–120 min. Liver specimens and serum samples were analyzed for transaminase levels, DNA damage, apoptosis, and proliferation. Repopulation experiments involved livers of dipeptidylpeptidase IV (DPPIV)-deficient rats preconditioned with RTPI (60–90 min) either with or without prior partial hepatic IR (25 Gy). After reperfusion intervals of 1 and 24 h, 12 million wild-type (DPPIV positive) hepatocytes were transplanted into recipient livers via the spleen. RTPI of 60–90 min caused limited hepatic injury through necrosis and induced a distinct regenerative response in the host liver. Twelve weeks following transplantation, small clusters of donor hepatocytes were detected within the portal areas. Quantitative analysis revealed limited engraftment of 0.79% to 2.95%, whereas control animals (sham OP) exhibited 4.16% (determined as relative activity of DPPIV when compared to wild-type liver). Repopulation was significantly enhanced (21.43%) when IR was performed prior to RTPI, optimum preconditioning settings being 90 min of ischemia and 1 h of reperfusion before transplantation. We demonstrate that RTPI alone is disadvantageous to donor cell engraftment, whereas the combination of IR with RTPI comprises an effective preparative regimen for liver repopulation. The method described clearly has potential for clinical application.

SnO2/CuO/polymer flexible thin films were prepared by a solution casting technology and characterized by high‐resolution TEM and XRD. The influences of key operational parameters on photocatalytic decolorization of azo dye (Biebrich Scarlet Red, BSR) were investigated systematically. The results showed good crystalline and clear lattice spacings of the novel composite photocatalyst. BSR was bleached effectively and the decolorization efficiency was >98 % in the presence of 1.0 g L–1photocatalyst under simulated solar light irradiation. The decolorization was more effective in acidic solution with the optimal pH in the range of 4–6. The tested co‐anions in general decreased the decolorization rates by decreasing the adsorption of BSR on the surface of the photocatalyst and reacting with positive hole (h+)/hydroxyl radicals (HO·).

Colony formation is one of the most important characteristics of the pluripotency of embryonic stem cells (ESC). On a flat surface of soft material such as polydimethylsiloxane (PDMS), the formation efficiency as well as the processing stability of ESC colonies is significantly lower than that on harder material surfaces. To still use PDMS as substrate for cell culture which is interesting for both microdevice fabrication and cell differentiation control, we deposited single nanofibers on PDMS for enhanced handling of ESCs. As expected, not only much more ESC colonies could be formed and stay on the PDMS surface with nanofibers but also they showed a narrow size distribution as compared to the results obtained on the PDMS surface without nanofibers.

Context.Anti-proton and positron Galactic cosmic ray spectra are among the key targets for indirect detection of dark matter. The boost factors, corresponding to an enhancement of the signal, and linked to the clumpiness properties of the dark matter distribution, have been taken as high as thousands in the past. The dramatic impact of these boost factors for indirect detection of antiparticles, for instance with the PAMELA satellite or the coming AMS-02 experiment, asks for their detailed calculation. Aims.We take into account the state-of-the-art results of high resolution N-body dark matter simulations to calculate the most likely energy dependent boost factors, which are linked to the cosmic ray propagation properties, for anti-protons and positrons. The results from extreme, but still possible, configurations of the clumpy dark matter component are also discussed. Methods.Starting from the mass and space distributions of sub-halos, the anti-proton and positron propagators are used to calculate the mean value and the variance of the boost factor for the primary fluxes. We take advantage of the statistical method introduced in Lavalle et?al. (2007) and cross-check the results with Monte Carlo computations. Results.By spanning some extreme configurations of sub-halo and propagation properties, we find that the average contribution of the clumps is negligible compared to that of the smooth dark matter component. Dark matter clumps do not lead to enhancement of the signals, unless they are taken with some extreme (unexpected) properties. This result is independent of the nature of the self-annihilating dark matter candidate considered, and provides precise estimates of the theoretical and the statistical uncertainties of the antimatter flux from sub-halos. Conclusions.Spectral distortions can still be expected in antimatter flux measurements, but scenarios invoking large and even mild clumpiness boost factors are strongly disfavoured by our analysis. Some very extreme configurations could still lead to large enhancements, e.g. (i) very small clumps with masses ?10-6?[Formula: see text] following a M-?mass distribution with ??2, highly concentrated with internal r-?profiles with ??1.5, and spatially distributed according to the smooth component; or (ii) a big sub-halo of mass ?07?[Formula: see text] within a distance of ? 1 kpc from the Earth. However, they are very unlikely from either theoretical or statistical arguments.

AbstractTwo silicon drift detectors combine with the new and nonconventional software pulse-height analyzer (SPHA) to measure the time evolution of soft-X-ray spectra, the thermal electron and superthermal electron temperatures. The high-quality soft-X-ray spectral distributions are easily obtained by the new SPHA. Therefore, the measurement accuracies and the time resolutions of thermal electron and superthermal electron temperatures are also improved. The enhancement phenomenon of superthermal electron avalanche during electron cyclotron resonance heating and the pronounced change for the time evolution of soft-X-ray spectra during supersonic molecular beam injection are observed by this system.

AbstractThe Experimental Advanced Superconducting Tokamak (EAST) was the first shaped tokamak of mega-ampere scale to achieve plasma utilizing a fully superconducting poloidal field coil system, and it is addressing ITER relevant superconducting constraints associated with the breakdown, plasma formation, and initial plasma current ramp. Electric field production for plasma start-up is severely limited in fully superconducting machines as a consequence of constraints associated with coil and lead voltages and eddy current heating in the superconducting coils. Such constraints motivate the use of electromagnetic modeling codes to design start-up scenarios for these devices. The successful first plasma campaign of the EAST superconducting tokamak was greatly facilitated by extensive and careful planning, development of appropriate modeling, simulation and diagnostic tools, a highly flexible plasma control system, and a highly experienced international collaboration team. We describe the design and modeling tools used to develop the first plasma scenario along with results of their application in the start-up campaign. Control design tools and plasma control algorithms utilized during the first campaign are discussed. Key physics, engineering, and operations results of the first plasma campaign are presented, including observations relevant to future devices such as ITER.

A well-defined, light-responsive copolymer poly(spiropyrane)-block-poly(ethylene glycol) (PSP-b-PEG) was synthesized by RAFT polymerization. The final copolymer can self-assembled into spherical micelles with a hydrophilic PEG corona and a hydrophobic spiropyrane core in aqueous solution. Moreover, the properties of micelles in aqueous solution were detected by fluorescence spectroscopy, UV–vis spectroscopy, dynamic light scattering (DLS), and scanning electron microscope (SEM). Model drug Nile Red was then encapsulated into the micelles and its light-controlled release was studied. In addition, an MTT assay provided the evidence for the low cell cytotoxicity of PSP-b-PEG micelles. The results demonstrate that the spherical micelles of PSP-b-PEG possess a potential application in smart drug delivery.Block polymer PEG-b-PSP could be self-assembled into micelles with a light-responsive hydrophobic block and stabilized by hydrophilic PEG coronae in aqueous solution, and the encapsulated drug can be released under UV light due to the transformation of SP structure to MC form.

ABSTRACTLysozyme is a commercially valuable enzyme, and is applied in many fields, concerning products such as foods, drugs and the like. In this work, the effect of foam fractionation on purification of lysozyme from chicken eggs was investigated. Experimental results indicated that the separating effectiveness was influenced significantly by the pH value and NaCl concentration, and the activity recovery and protein recovery reached the highest point of 40% and 60%, respectively at pH 7.0 and NaCl 0.3M. For the effect of detergents, with the addition of SDS, CTAB, Triton X-100 or Tween 80, the protein recoveries were 93%, 88%, 68% or 72%, and the activity recovery were 30%, 20%, 55% or 58%, respectively. The addition of SDS and CTAB resulted in the higher protein recovery and lower activity recovery, which may be related to their inhibition for enzyme activity. To testify the hypothesis, the formate were collected from egg white with the parameters of pH 7.0, NaCl 0.3M and 200mM SDS, and then 13mM β-cyclodextrin was added to the foamate solution to stripe off SDS away. The data showed that the activity recovery and protein recovery were 84% and 90%, respectively, increasing significantly. Above results indicated that the foam fractionation should be a potential method for purification of lysozyme from chicken egg.

A mathematical model including convection, axial dispersion, external‐ and intraparticle mass transfer resistances, particle size distribution (PSD) and variation of isotherm (VOI) was developed for analyzing the adsorption process of solanesol by macroporous resins. The theoretical predictions were compared with the experimental data obtained at different conditions to examine the validity of the model. The results showed that the theoretical predictions were very consistent with the experimental data. The model parameters were investigated using the model developed. The results showed that: (a) As Pe, Bi, m, n, and aincreased and bdecreased, the time required to reach the breakthrough point was delayed and the loading capacity at the breakthrough point was increased; (b) When Pe is greater than 50, the effect of axial diffusion decreased to a negligible level, and (c) At the region of low values of mand n, the breakthrough curves changed severely and the adsorption column was penetrated through easily.

Munc13-1 may be a key factor in regulating insulin exocytosis, but its exact expression and role have not been clarified yet, especially during pancreatic development. We attempted to investigate the expression and function of Munc13-1 during embryonic pancreatic development in rats and determine the effects on insulin secretion. In the present study, pancreata of rats at embryonic day 12.5 (E12.5), E15.5, E18.5, new-born, 21 after birth (P21), and adult stage were dissected under microscope. The rat model of intrauterine growth retardation (IUGR) was made by 50% calorie restriction in pregnant rats from gestational day 15 until term. The expression of Munc13-1 and insulin secretion was studied by the techniques of RT-PCR, real-time PCR, Western blot, and enzyme-linked immunosorbent assay. Immunohistochemistry and immunofluorescence were used to define the location of Munc13-1. We found that Munc13-1 was located at islet along with insulin. Insulin- and Munc13-1-specific mRNA were not detected until E12.5 and E15.5, respectively, and increased with the development of the fetus. Western blot showed that Munc13-1 was low at E15.5 and E18.5 and increased later. The blood insulin level and Munc13-1 were reduced simultaneously in IUGR newborn rats compared with normal ones. These results suggest that Munc13-1 exists in pancreas islets during fetus development and its deficiency in the pancreas, as occurs in IUGR, was in accordance with decreased blood insulin level. Munc13-1 may play an essential role in insulin exocytosis.

We present a new type of CeO 2nanodevice in which a single CeO 2nanowire was used as the sensing unit. It was found that incorporation of Pt nanocrystals on CeO 2nanowire could significantly increase the sensor response. A possible mechanism was discussed based on the study of morphology and surface bond states of the nanowire using local electron energy loss spectroscopy and X-ray photoemission spectroscopy. The results provide a pathway to improve the performance of gas sensors with a good understanding of the nanowire’s surface physics and chemistry.

In the present study, the preparative purification of solanesol by macroporous resins was studied. The adsorption and desorption properties of solanesol on macroporous resins including SP207, SP700, SP825, SP850 and HP20 were compared. SP850 resin offered the best adsorption and desorption capacities based on the research results. Both Langmuir and Freundlich isotherms were used to describe the interactions between the solutes and resin at different temperatures, and the experimental data fits best to the Freundlich isotherms. Adsorption and desorption kinetic curves were obtained for solanesol adsorption on SP850 resin in the temperature range of 298–303 K. The results showed that the mobility of solanesol adsorption increased and the proportion of adsorbed solanesol decreased with increasing temperature. The adsorption kinetic curve can be classified into three portions, i.e., instantaneous adsorption stage, intraparticle diffusion stage and the final equilibrium stage. Dynamic adsorption and desorption experiments were carried out with the column packed by SP850 resin to optimize the separation process. The isocratic and stepwise operations were designed for the separation of solanesol. The use of stepwise elution allowed a reduction in the process time and solvent consumption, but also led to some loss in purity. The corresponding optimal parameters for adsorption and desorption were determined. According to the research results, it can be concluded that SP850 resin possesses a good ability to separate solanesol and the results in this study may provide scientific references for large‐scale solanesol production from tobacco leaf extracts.

This review paper describes the livestock production systems in China, their status and trends, driving factors, and major issues with profound impact. Three distinct livestock production systems are discussed; grazing, mixed farming, and industrial systems. The ?grazing system' is generally characterised by harsh climate, rangeland, and low livestock output. Market forces, biophysical constraints and environmental concerns are putting a ceiling on the potential for intensification of the grazing system except in some areas where the agro-ecological potential permits. This system needs to be re-oriented towards adding ecosystem service provision, rather than mere production or subsistence. The ?mixed farming system', with the highest share of most kinds of livestock commodities, forms the backbone of China's agriculture and is undertaking a notable intensification and specialisation process. The ?industrial system' is geographically concentrated in areas close to densely populated demand centers. Although growing fast, the share of national livestock output remains relatively small. The past two decades have seen a rapid growth in both consumption and production of livestock food products in China. This new food revolution has been driven to a great extent by the rapid growing economy, personal income and urbanisation. Among the most important issues related to livestock production systems in China are severe rangeland degradation, caused mainly by overexploitation of these lands, increasing demand and competition for feed grain, and environmental and public health risks associated with industrialised livestock production. China will have to cope with such challenges through proper policy and technological interventions to sustain the livestock development and simultaneously secure the natural resources and environmental health.

The influence of nanoclay particles on the nonisothermal crystallization behavior of intercalated polyethylene (PE) prepared by melt‐compounding was investigated. It is observed that the crystallization peak temperature (Tp) of PE/clay nanocomposites is slightly but consistently higher than the neat PE at various cooling rates. The half‐time (t0.5) for crystallization decreased with increase in clay content, implying the nucleating role of nanoclay particles. The nonisothermal crystallization data are analyzed using the approach of Avrami (Polymer 1971, 12, 150), Ozawa (Polym Eng Sci 1997, 37, 443), and Mo and coworkers (J Res Natl Bur Stand 1956, 57, 217), and the validity of the different kinetic models to the nonisothermal crystallization process of PE/clay nanocomposites is discussed. The approach developed by Mo and coworkers successfully explains the nonisothermal crystallization behavior of PE and PE/clay nanocomposites. The activation energy for nonisothermal crystallization of neat PE and PE/clay nanocomposites is determined using the Kissinger (J Res Natl Bur Stand 1956, 57, 217) method. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3809–3818, 2006

AbstractReal-world road accident data involving pedestrians were obtained from police records in Beijing. In total, 158 vehicle–pedestrian accidents were included in this study, from which the accident characteristics were identified. The data were analysed and the overall epidemiology established. In addition representative cases were studied in depth using MADYMO reconstructions. For accuracy, a MADYMO pedestrian model based on Chinese anthropometric values was developed. A comparable European-size MADYMO model has also been used to demonstrate the differences between the two anthropometric types. Using the Chinese pedestrian model, a complete accident event is reconstructed, in terms of pre-impact behaviour, causation, injury characteristics and post-impact kinematics.

Two‐dimensional compressible momentum equations were solved by a perturbation analysis and the PISO algorithm to investigate the effects of compressibility and rarefaction on the local flow resistance of isothermal gas flow in circular microchannels. The computations were performed for a wide range of Reynolds numbers and inlet Mach numbers. The explicit expression of the normalized local Fanning friction factor along the microchannel was derived in the present paper. The results reveal that the local Fanning friction factor is a function of the inlet Mach number, the Reynolds number and the length‐diameter ratio of the channel. For larger Reynolds and inlet Mach numbers, the friction coefficient in the microchannel is higher than the value in a macrotube, and the gas flow in the microchannel is dominated only by compressibility. For smaller Reynolds and inlet Mach numbers, the Fanning friction factor of gas flow in the microchannel is lower than that in a circular tube of conventional size due to slip flow at the wall and thus, rarefaction has a significant effect on the fluid flow characteristics in a microchannel.

By means of a two-layered ONIOM approach, we predict that sidewall epoxidation of single-walled carbon nanotubes (SWNTs) with dioxiranes is viable. The SWNT epoxides thus produced could be precursors for further chemical modification of SWNTs, given the abundant and well-established chemistry of organic epoxides. This opens the door for routine chemical manipulation of SWNTs.

trans-4-Oxo-2-nonenal (ONE) has recently been demonstrated to be a direct product of lipid peroxidation. In earlier studies to elucidate the structure of the trans-4-hydroxy-2-nonenal (HNE)-derived fluorescent Lys−Lys cross-link, we showed that ONE was capable of both oxidative and nonoxidative cross-linking of amines. A more comprehensive study on nonoxidative modification of protein nucleophiles by ONE is described here, focusing on the initial Michael addition of imidazole, thiol, and amine groups to C2 or C3 to give 4-keto aldehydes that can then condense with amines to form nucleophile-substituted pyrroles. 2,3-Substituted pyrroles (major) and 2,4-substituted pyrroles (minor) were distinguished by 2D NMR techniques, and N^τ-substitution is preferred over N^π-substitution in the Michael addition of histidine. Mechanisms of both nonoxidative and oxidative side chain reactions of ONE are discussed, as is the relative propensity (ONE > HNE) to induce cross-linking of the model proteins ribonuclease A and β-lactoglobulin.

With the objective of making calcium alginate gel beads with small and uniform size, membrane emulsification coupled with internal gelation was proposed. Spherical gel beads with mean size of about 50 μm, and even smaller ones in water, and with narrow size distribution were successfully obtained. Experimental studies focusing mainly on the effect of process parameters on bead properties were performed. The size of the beads was mainly dependent on the diameter of the membrane pores. High transmembrane pressure made for large gel beads with wide size distribution. Low sodium alginate concentration produced nonspherical beads, whereas a high concentration was unsuitable for the production of small beads with narrow distribution. Thus 1.5% w/v was enough. A high surfactant concentration favored the formation of small beads, but the adverse effect on mass transfer should be considered in this novel process. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 848–852, 2003

Abstract. In this study we describe a 239-kb region on the long arm of rice chromosome 10 that contains a high density (71%) of locally duplicated genes, including 24 copies of a glutathione S-transferase gene. Intriguingly, embedded within this cluster is a large insertion (~33 kb) of rice (Oryza sativa) chloroplast DNA that is derived from two separate regions of the chloroplast genome. We used DNA fiber-based fluorescence in situ hybridization (fiber-FISH) analyses of O. sativa spp. japonica nuclei to confirm that the insertion of organellar DNA was not a cloning artifact. The sequence of the chloroplast insertion is nearly identical (99.7% identity) to the corresponding regions in the published rice chloroplast genome sequence, suggesting that the transfer event occurred recently. PCR amplification and sequence analysis in two subspecies of rice, O. sativa spp. japonica and spp. indica, indicates that the transfer event predated the divergence of these two subspecies. The chloroplast insertion is flanked by a 2.1-kb perfect direct repeat that is unique to this location in the rice genome.