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Abstract Background Dendritic cells (DCs) initiate immune responses through their direct interaction with effector cells. However, the mechanism by which DC activity is regulated is not well defined. Previous studies have shown that CTLA4 on T cells regulates DCs function by "cross-talk". We investigated whether there is an intrinsic regulatory mechanism in DCs, with CTLA4 as a candidate regulator. Results We confirmed via RT-PCR and flow cytometry the natural expression of CTLA4 on mature DCs derived from human monocytes. Approximately 8% CD1a-positive cells express CTLA4 both on surface and intracellular, whereas 10% CD1a-negative cells express CTLA4 intracellularly, but little expression was observed on the cell surface. The cross-linking of CTLA4 inhibits DCs maturation and antigen presentation in vitro, but does not inhibit endocytosis. Conclusions CTLA4 is expressed by DCs and plays an inhibitory role. CTLA4-expressing DCs may represent a group of regulatory DCs. Because of its wide distribution on different cell types, CTLA4 may play a general role in regulating immune responses.

Sargassum horneri (Turner) C. Agardh is a genus of brown algae and plays an important role in marine ecosystem. However, the inhabiting area of S. horneri has been decreasing sharply in China. To understand the photoacclimation and photoregulation strategies of S. horneri in responses to temperature and light, S. horneri was cultured under different temperatures [18°C (LT) and 26°C (HT)] and light intensities [60 µmol(photon) m-2 s-1 (LL) and 120 µmol(photon) m-2 s-1 (HL)] for 7 d, and then the chlorophyll a fluorescence parameters were measured. The results showed that the maximum electron transfer rate occurred at low temperature and high light (LT-HL) condition. The high temperature was the predominant factor for causing inhibition of PSII, lowering the effective quantum yield of PSII, and reducing the nonphotochemical quenching (NPQ). However, high light could improve the photoprotective ability via enhancing the NPQ. On the other hand, a strong linear relationship was observed between NPQ and the electron transport efficiency (a); the increase of NPQ could reduce the a value and avoid damage from high light stress to PSII. Therefore, S. horneri was found to be well adapted to grow under LT-HL conditions. [ABSTRACT FROM AUTHOR]

We investigate whistler‐mode waves and broadband electrostatic waves (EWs) within an ion diffusion region (IDR) at the magnetopause. The quasi‐parallel whistlers are observed in the separatrix regions associated with the electron anisotropy or loss cone, while the oblique whistlers, the Buneman‐type waves, and the oblique EWs are observed in the center of the current sheet associated with the accelerated electron or ion beams. The whistlers are linked with Buneman‐type waves by the electron Pacman distribution rather than the wave‐wave process. The accelerated cold electron beams excite the Buneman‐type instabilities and make the anisotropy or loss cone of hot electrons less apparent, which led to the conversion of the whistlers from quasi‐parallel to oblique. Additionally, the oblique EWs are associated with the ion beams produced by the multiple X‐line reconnection. These results provide a further understanding of the relation between plasma waves and plasma kinetics in the IDR. Plain Language Summary: The whistler waves and the broadband electrostatic waves are two common waves produced by magnetic reconnection in space plasma. Generally, the whistler waves have two modes, the quasi‐parallel and the oblique to the ambient magnetic field associated with different generation mechanisms. Both of them have been observed in the magnetic reconnection, but their relation is still unclear. The broadband electrostatic waves are sometimes simultaneously observed with the oblique whistlers. The relationship between them is also inconclusive. Here, we present a new view of the relation between the quasi‐parallel whistlers, the oblique whistlers, and the broadband electrostatic waves. They are linked by the evolution of electron Pacman distribution, which is composed of the hot magnetospheric population with the loss cone and the cold accelerated magnetosheath beam characteristic for magnetopause reconnection, in the reconnection diffusion region rather than the wave‐wave process. Besides, the oblique electrostatic waves associated with ion beams are observed in the diffusion region. These results advance our understanding of the relation between plasma waves and magnetic reconnection. Key Points: Large‐amplitude electromagnetic and electrostatic waves are observed in the separatrices and center of the diffusion region, respectivelyQuasi‐parallel whistlers, oblique whistlers, and Buneman‐type waves are linked via the evolution of electron Pacman distributionThe oblique broadband electrostatic waves associated with the ion beams are observed in the diffusion region [ABSTRACT FROM AUTHOR]

Magnetic reconnection and turbulence are the two most important energy dissipation processes in plasma. These two processes intertwine with each other and play important roles in their respective dynamic evolution. Here, we present the first evidence that secondary reconnections occur in the turbulent outflow driven by a primary reconnection in the Earth's magnetotail. We have identified 14 secondary reconnections in a large number of current filaments in the turbulent outflow, which persisted for about one and half an hour. Most of these secondary reconnections were electron‐only reconnection that has recently been discovered in the magnetosheath. These secondary reconnections entangled the magnetic field lines and dissipated the magnetic energy in the outflow region far away from the primary X line. Plain Language Summary: Magnetic reconnection usually evolves into turbulent state. The role of turbulence in reconnection is one of the most outstanding questions in reconnection. By using the unprecedented high‐cadence data from the magnetospheric multiscale mission, we present the first evidence that secondary reconnections occur in the turbulent outflow driven by a primary reconnection in the Earth's magnetotail. Most of these secondary reconnections occurred in electron‐scale current sheets and were without ion couplings. These secondary reconnections future released energy in the outflow region besides the primary X line. These results are important for understanding the turbulent reconnection, which is ubiquitous in the astrophysical system but barely investigated by in situ measurements. Key Points: First observation of secondary reconnections in the turbulent outflow driven by primary reconnectionThese secondary reconnections occurred in current sheets with broad shear angles and different orientationsMost of these secondary reconnections were without clear ion couplings [ABSTRACT FROM AUTHOR]

The ability to identify erroneous depth estimates is of fundamental interest. Information regarding the aleatoric uncertainty of depth estimates can be, for example, used to support the process of depth reconstruction itself. Consequently, various methods for the estimation of aleatoric uncertainty in the context of dense stereo matching have been presented in recent years, with deep learning-based approaches being particularly popular. Among these deep learning-based methods, probabilistic strategies are increasingly attracting interest, because the estimated uncertainty can be quantified in pixels or in metric units due to the consideration of real error distributions. However, existing probabilistic methods usually assume a unimodal distribution to describe the error distribution while simply neglecting cases in real-world scenarios that could violate this assumption. To overcome this limitation, we propose two novel mixed probability models consisting of Laplacian and Uniform distributions for the task of aleatoric uncertainty estimation. In this way, we explicitly address commonly challenging regions in the context of dense stereo matching and outlier measurements, respectively. To allow a fair comparison, we adapt a common neural network architecture to investigate the effects of the different uncertainty models. In an extensive evaluation using two datasets and two common dense stereo matching methods, the proposed methods demonstrate state-of-the-art accuracy. [ABSTRACT FROM AUTHOR]

Two‐dimensional Hall reconnection model can explain the fast release of magnetic energy and most of its predictions have been demonstrated by in situ satellite observations. However, the three‐dimensional effect to reconnection remains poorly known. Recent numerical simulations have shown that three‐dimensional evolution is more complex than two‐dimensional in that reconnection occurs in multiple sites that are not necessarily in the primary neutral current sheet. Here, we present the first observational evidence for localized secondary reconnection at the separatrix surface of a magnetic flux rope (MFR). This secondary reconnection occurs between the axial magnetic field of the MFR, which points out‐of‐plane of the Earth's magnetopause reconnection, and the magnetospheric field. This three‐dimensional electron‐scale reconnection in the exhaust facilitates the cross‐scale energy conversion from the macro‐scale down to electron‐scale. Plain Language Summary: Magnetic reconnection releases large amounts of magnetic energy in astrophysical, space and laboratory plasmas. For the decades, the reconnection has been investigated largely based on two‐dimensional models while the three‐dimensional effect to reconnection remains poorly known. It has been shown by numerical simulation that three‐dimensional evolution, because of the freedom in the out‐of‐plane direction, is turbulent and distinct from the two‐dimension laminar reconnection in that reconnection occurs in multiple sites that are not necessarily in the primary neutral current sheet. The turbulent reconnection is characterized by the formation and interaction of multiple flux ropes, or chaotic magnetic field lines in the outflow region. Although small‐scale magnetic flux ropes and their interactions have been observed, one important missing piece is whether reconnection occurs at the region away from the neutral current sheet. Here we present the first evidence for localized secondary reconnection at the separatrix surface of the primary reconnection. This secondary reconnection occurs between the axial magnetic field of the flux rope, which points out‐of‐plane of the magnetopause reconnection, and the magnetospheric field. This three‐dimensional patchy reconnection in the exhaust facilitates the cross‐scale energy conversion from the macro‐scale down to electron‐scale and leads to a turbulent evolution of reconnection. Key Points: Three‐dimensional secondary electron‐scale reconnection was observed at the separatrix of a flux rope in the magnetosphereNew light on the destiny of flux rope from a three‐dimensional perspective: dissipation through the reconnection of the core fieldThe cross‐scale energy conversion is through the formation and dissipation of flux ropes [ABSTRACT FROM AUTHOR]

OBJECTIVE: Many studies have been published recently on the characteristics of the clinical manifestations of COVID-19 in children. The quality scores of literature are different, and the incidence of clinical manifestations and laboratory tests results vary greatly. Therefore, a systematic retrospective meta-analysis is needed to determine the incidence of the clinical manifestations of COVID-19 in children. MATERIALS AND METHODS: Data from databases, such as PubMed, Web of science, EMBASE, Johns Hopkins University, and Chinese databases were analysed from January 31, 2020 to October 20, 2020. High-quality articles were selected for analysis based on a quality standard score. A meta-analysis of random effects was used to determine the prevalence of comorbidities and subgroup meta-analysis to examine the changes in the estimated prevalence in different subgroups. RESULTS: Seventy-one articles involving 11,671 children were included in the study. The incidence of fever, respiratory symptoms, gastrointestinal symptoms, asymptomatic patients, nervous system symptoms, and chest tightness was 55.8%, 56.8%, 14.4%, 21.1%, 6.7%, and 6.1%, respectively. The incidence of multisystem inflammatory syndrome was 6.2%. Laboratory examination results showed that lymphocytes decreased in 12% and leukocytes decreased in 8.8% of patients, whereas white blood cells increased in 7.8% of patients. Imaging showed abnormalities in 66.5%, and ground-glass opacities were observed in 36.9% patients. Epidemiological history was present in 85.2% cases; severe disease rate was 3.33%. The mortality rate was 0.28%. CONCLUSIONS: The clinical symptoms of COVID-19 in children are mild, and laboratory indicators and imaging manifestations are atypical. While screening children for COVID-19, in addition to assessing patients for symptoms as the first step of screening, the epidemiological history of patients should be obtained. [ABSTRACT FROM AUTHOR]

Background: The prognosis of patients with biliary atresia (BA) after Kasai portoenterostomy (KPE) varies, and precisely predicting the outcomes of KPE before surgery is still challenging.Methods: A total of 158 patients who underwent KPE in our hospital were included in this study. The patients in the training cohort were recruited from January 2012 to October 2017 (n = 118), and then, those in the validation cohort were recruited from November 2017 to April 2019 (n = 40). Combined nomogram models were developed based on two-dimensional shear wave elastography (2D SWE) values and other biomarkers. The utility of the proposed models was evaluated by C-index.Results: 2D SWE played a potentially important role in predicting native liver survival (NLS) of BA patients with a C-index of 0.69 (0.63 to 0.75) in the training cohort and 0.76 (0.67 to 0.85) in the validation cohort. The nomogram A based on 2D SWE values, age, gamma-glutamyl transferase (GGT) and aspartate aminotransferase-to-platelet ratio (APRI) had a better C-index in the training cohort [0.74 (0.68-0.80) vs. 0.66 (0.60-0.73), P = 0.017] and in the validation cohort [0.78 (0.70-0.86) vs. 0.60 (0.49-0.71), P = 0.002] than the nomogram B (without 2D SWE). Using risk score developed from nomogram A, we successfully predicted 88.0% (22/25) of patients in the training cohort and 75.0% (9/12) in the validation cohort to have survival time of less than 12 months after KPE.Conclusion: The combined nomogram model based on 2D SWE values, age, GGT and APRI prior to KPE can effectively predict NLS in BA infants. [ABSTRACT FROM AUTHOR]

Nonisothermal densification in 8% yttria doped zirconia (8YSZ) particulate matter of 250 nm median particle size was studied under 215 V/cm dc electric field and 9 °C/min heating rate, using time-resolved in-situ high temperature energy dispersive x-ray diffractometry with a polychromatic 200 keV synchrotron probe. Densification occurred in the 876-905 °C range, which resulted in 97% of the theoretical density. No local melting at particle-particle contacts was observed in scanning electron micrographs, implying densification was due to solid state mass transport processes. The maximum current draw at 905 °C was 3 A, corresponding to instantaneous absorbed power density of 570 W/cm3. Densification of 8YSZ was accompanied by anomalous elastic volume expansions of the unit cell by 0.45% and 2.80% at 847 °C and 905 °C, respectively. The anomalous expansion at 905 °C at which maximum densification was observed is characterized by three stages: (I) linear stage, (II) anomalous stage, and (III) anelastic recovery stage. The densification in stage I (184 s) and II (15 s) was completed in 199 s, while anelastic relaxation in stage III lasted 130 s. The residual strains ([variant_greek_epsilon]) at room temperature, as computed from tetragonal (112) and (211) reflections, are [variant_greek_epsilon](112) = 0.05% and [variant_greek_epsilon](211) = 0.13%, respectively. Time dependence of (211) and (112) peak widths (β) show a decrease with both exhibiting a singularity at 905 °C. An anisotropy in (112) and (211) peak widths of {β(112)/β(211)} = (3:1) magnitude was observed. No phase transformation occurred at 905 °C as verified from diffraction spectra on both sides of the singularity, i.e., the unit cell symmetry remains tetragonal. We attribute the reduction in densification temperature and time to ultrafast ambipolar diffusion of species arising from the superposition of mass fluxes due to Fickian diffusion, thermodiffusion (Soret effect), and electromigration, which in turn are a consequence of a superposition of chemical, temperature, and electrical potential gradients. On the other hand, we propose defect pile-up at particle-particle contacts and subsequent tunneling as a mechanism creating the 'burst-mode' discontinuous densification at the singularities observed at 847 and 905 °C. [ABSTRACT FROM AUTHOR]

Hypereutectic 0.8MgO-0.2Y2O3 nanocomposites were studied using high pressure and high temperature in situ synchrotron energy dispersive x-ray diffractometry at 5.5 GPa and 1273 K. Polymorphic transformations in the Y2O3 phase, which resulted in a quadruple phase equilibria among cubic, hexagonal, and monoclinic phases with cubic MgO, were observed at 298 K under 5.5 GPa-a pressure much smaller than the pressures at which polymorphic transitions in macroscopic Y2O3. Time-resolved diffractometry at (1273 K, 5.5 GPa, 120 min) revealed a 0.87% expansive volumetric lattice strain in MgO, and is attributed to solid solution formation with Y2O3 which is otherwise absent at ambient conditions. The residual MgO unit cell volume expansion is 0.69% at 298 K, which is indicative that yttrium remained in solid solution. The macroscopic shrinkage due to densification at (1273 K, 5.5 GPa, 120 min) is 3.45% by volume. The partial molar volume of Y3+ in the solid solution is smaller than its molar volume in the pure state per thermodynamic considerations. The importance of repulsion among O2- ions in the immediate vicinity of a Mg2+ vacancy as well as misfit strain due to differences in ionic radii upon Y3+ substitution on Mg2+ sites is presented. A self-consistent model and explanation for the observed concomitant occurrence of cubic → monoclinic and cubic → hexagonal polymorphic transitions in Y2O3 and their stabilization at room temperature is proposed. [ABSTRACT FROM AUTHOR]

In this paper, the pressure (P) and shear vertical (SV) wave propagation in the periodically layered fluid and piezoelectric structure are theoretically studied. A single piezoelectric layer is first analyzed for three scenarios: piezoelectricity-ignored, electrically open, or electrically closed. It is observed that both the Lamb wave dispersion curves and the transmission coefficients are affected by piezoelectricity and electrical boundary conditions under any incident angle. From the analyses of the periodically layered structure, it is further found that the piezoelectricity and the electrical boundary conditions have influence on band gaps for a given incident angle. [ABSTRACT FROM AUTHOR]

We report a Magnetospheric Multiscale (MMS) mission observation of magnetic reconnection occurring at the edge of a large‐scale magnetic flux rope (MFR), the cross‐section of which was about 2 RE. The MFR was observed at the duskside in the Earth's magnetotail and was highly oblique with its axis approximately along the XGSM direction. We find an electron‐scale current sheet near the edge of this MFR. The Hall magnetic and electric field, super‐Alfvénic electron outflow, parallel electric field, and positive energy dissipation were observed associated with the current sheet, which indicates that MMS detected a reconnecting current sheet with a large guide field. Interestingly, ions were not coupled in this reconnection, akin to the electron‐only reconnection observed in the turbulent magnetosheath. We further find that the electron‐only reconnection is commonly associated with a macroscopic MFR. This result will shed new light on understanding the multiscale coupling associated with an MFR in space plasmas. Key Points: MMS observed an electron‐only reconnection at the edge of a macroscopic magnetic flux rope in the magnetotailElectron‐only reconnection is ubiquitous in space plasma [ABSTRACT FROM AUTHOR]

OBJECTIVE: Long non-coding RNA (lncRNA) HMGA1P4 has been previously reported to be upregulated in gastric cancer (GC). This study aims to investigate the role of HMGA1P4 in cisplatin (DDP)-resistant GC. PATIENTS AND METHODS: HMGA1P4 levels in DDP-resistant GC tissues and cells were determined. Regulatory effects of HMGA1P4 on proliferative and apoptotic abilities in DDP-resistant GC cells and their parental cells were assessed. At last, expression levels of genes associated with multidrug-resistance (MDR) (MDR1, MRP1, mTOR and HIF-1α) and apoptosis (Bax, Bcl-2 and Caspase3) were determined in DDP-resistant GC cells. RESULTS: Results revealed that HMGA1P4 was upregulated in DDP-resistant GC tissues and cells. Overexpression of HMGA1P4 stimulated proliferative rate and suppressed apoptosis in both DDP-resistant GC cells and their parental cells. Moreover, in DDP-resistant GC cells, overexpression of HMGA1P4 upregulated MDR-related genes and downregulated apoptosis- related genes. CONCLUSIONS: HMGA1P4 is upregulated in DDP-resistant GC tissues and cells, and triggers the progression of DDP-resistance in GC. [ABSTRACT FROM AUTHOR]

A Fe-based multi-component alloy, 60Fe-12Cr-10Mn-15Cu-3Mo, which presents higher yield stress than typical stainless steels (such as 304, 316, and 340), was used to investigate the thermal stability of irradiation-induced defects. Neutron irradiation was carried out at approximately 323 and 643 K using up to 1.3 × 10−3 and 4.5 × 10−4 dpa (displacements per atom), respectively. While no defects were accumulated at the high temperature of 643 K, single vacancies were formed after irradiation at the low temperature of 323 K to 1.3 × 10−3 dpa, and the vacancies became mobile at 423 K. As a result, vacancy clusters were formed. However, as the annealing temperature increased the size of vacancy clusters decreased. Coincidence Doppler broadening measurements indicated that Cu precipitates were the sites of vacancy cluster formation, and the recovery of vacancy clusters became prominent while annealing the irradiated sample at temperatures higher than 423 K. Recovery of vacancy clusters at 573 K, which was not a high temperature, was also observed even in the sample that was irradiated using 2.5 MeV Fe ions at room temperature to 0.6 dpa at damage peak. [ABSTRACT FROM AUTHOR]

In order to investigate the interactive effects of simulated acid rain and copper (Cu) on macroalgae, Sargassum horneri was cultured under pH of 8.2, 5.6, 4.5 and Cu concentrations of 0, 25, 100 µg L-1. Under the medium concentration of Cu, moderate pH mitigated the toxicity of Cu on S. horneri, while the low pH and high Cu concentration reduced the contents of chlorophyll (Chl) a and carotenoids. Furthermore, pH had no interaction with Cu on maximal Chl fluorescence or electron transport efficiency, while effective PSII quantum yield, maximum electron transport rate, and saturating irradiance were obviously affected by pH and Cu, and the interactive effects were significant. Additionally, with the increasing Cu concentration and decreasing pH, nonphotochemical quenching and regulated energy dissipation dropped sharply, while nonregulated energy dissipation increased. Therefore, the high concentration of Cu and low pH had synergistic effects on the photosynthetic performance and growth of S. horneri. [ABSTRACT FROM AUTHOR]

Hepatitis B virus (HBV) infection is a major public health issue with serious medical consequences. The roles of microRNAs (miRNAs) in HBV replication and expression have been generally recognized, and the abnormal expression of miR-501 has been reported in patients with HBV infection. However, the function and mechanism in HBV replication remain elusive. The expression patterns of miR-501-3p and ZEB2 in HBV-related hepatocellular carcinoma (HCC) tissues and HBV-expressing HCC cells were determined by qRT-PCR and western blot assays. HBV replication and expression were evaluated through detecting the copies of HBV DNA and the secretion of HBV surface antigens HBsAg and HBeAg by real-time PCR and ELISA analyses. Bioinformatics and dual-luciferase reporter analyses were employed to validate the functional interaction between miR-501-3p and ZEB2. miR-501-3p was significantly upregulated, while ZEB2 was downregulated in HBV-related HCC tissues and cells compared with relative controls without HBV infection. Knockdown of miR-501-3p hampered HBV replication and gene expression in HepG2.2.15 and HepAD38 cells. ZEB2 was identified as a functional target of miR-501-3p. The absence of ZEB2 abolished the inhibitory effects of anti-miR-501-3p on HBV replication and gene expression. Our data indicated that miR-501-3p participated in the regulation of HBV replication and gene expression partially via repressing ZEB2 in HepG2.2.15 and HepAD38 cells, providing a promising antiviral avenue for HBV infection. [ABSTRACT FROM AUTHOR]

Recent technological advancement in flexographic printing has allowed flexography to catch up with other R2R processes such as gravure printing in the printed electronics field. However, there are many process parameters involved in flexography that can affect the print quality. This work attempted to achieve finer line printing compared to the current 45–100 µm printed line width range of flexography by manipulating and studying these process parameters. A design of experiments was conducted to investigate the influence and interaction of various process parameters such as anilox volume, anilox force and printing force on the printed line width. After identifying the key process parameter from the design of experiments, another in-depth study of the key process parameter was conducted to further investigate how printed line width was affected. The results showed that the printing plate was elastically deformed with a range of 50–400 N printing forces. Beyond the 400-N printing force, the printing plate experienced plastic deformation. [ABSTRACT FROM AUTHOR]

High‐speed railway (HSR) is becoming one of the most effective and important transportation modes. To ensure the safety of HSR, a stable communication system is necessary. The understanding of propagation characteristics of radio channel is important for HSR communication system design. In this paper, a wideband measurement in suburban HSR scenarios at 460 MHz is presented. Some typical channel parameters such as the large‐scale fading, Ricean K factor, power‐delay profile, and root‐mean‐square delay spread are extracted from the measurement data. The different distributions of small‐scale fading are also compared. The relationships between the channel parameters and the distance of transmitter (base station) and receiver are also explored. The results could provide a reference for the design and evaluation of HSR communication network, especially for the Long‐Term‐Evolution (LTE)‐railway system. Key Points: Measurements in the high‐speed railway environment at the LTE‐R band are conducted in ChinaChannel characterization including both of large‐scale parameters and small‐scale parameters are presentedDistance dependency of channel parameters and correlation characteristics are investigated [ABSTRACT FROM AUTHOR]

Rumen-protected betaine (RPB) can enhance betaine absorption in the small intestine of ruminants, while betaine can alter fat distribution and has the potential to affect the meat quality of livestock. Hence, we hypothesized that RPB might also affect the meat quality of lambs. Sixty male Hu sheep of similar weight (30.47 ± 2.04 kg) were selected and randomly subjected to five different treatments. The sheep were fed a control diet (control treatment, CTL); 1.1 g/day unprotected-betaine supplemented diet (UPB); or doses of 1.1 g/day (low RPB treatment; L-PB), 2.2 g/day (middle RPB treatment; M-PB) or 3.3 g/day (high RPB treatment; H-PB) RPB-supplemented diet for 70 days. Slaughter performance, meat quality, fatty acid and amino acid content in the longissimus dorsi (LD) muscle, shoulder muscle (SM) and gluteus muscle (GM) were measured. Compared with CTL, betaine (including UPB and RPB) supplementation increased the average daily weight gain (ADG) (P < 0.05) and average daily feed intake (P < 0.01) of lambs. Rumen-protected betaine increased ADG (P < 0.05) compared with UPB. With increasing RPB doses, the eye muscle area of the lambs linearly increased (P < 0.05). Compared with CTL, betaine supplementation decreased water loss (P < 0.05) in SM and increased pH24 in the SM (P < 0.05) and GM (P < 0.05). Compared with UPB, RPB decreased water loss in the GM (P < 0.01), decreased shear force (P < 0.05) in the LD and SM and increased the pH of the meat 24 h after slaughter (pH 24 ). With increasing RPB doses, the shear force and b* value in the LD linearly decreased (P < 0.05), and the pH24 of the meat quadratically increased (P < 0.05). Compared with CTL, betaine supplementation increased the polyunsaturated fatty acid in the GM (P < 0.05). Compared with UPB, RPB supplementation decreased the saturated fatty acid (SFA) content in the LD (P < 0.05) and increased the unsaturated fatty acids (UFA), mono-unsaturated fatty acids and UFA/SFA ratio in the LD (P < 0.05). Compared with CTL, the content of histidine in the LD increased with betaine supplementation. Compared with UPB, RPB supplementation increased the content of total free amino acids and flavor amino acids in the LD of lambs (P < 0.05). With increasing RPB, the isoleucine and phenylalanine contents in the LD linearly increased (P < 0.05). Overall, the data collected indicated that the meat quality of lambs (especially in the LD) improved as a result of betaine supplementation, and RPB showed better effects than those of UPB. [ABSTRACT FROM AUTHOR]

In this work, a giant exchange bias field of over 1 kOe, which is uncommon in film systems, is obtained in all-3d-metal Heusler-type Ni38.8Co2.9Mn37.9Ti20.4 thin films. The thermomagnetic curves show an unambiguous noncoincidence between zero-field-cooled and field-cooled protocols, indicating the presence of magnetically inhomogeneous phases in the film in the low temperature range. Magnetic measurements, including magnetic relaxation and magnetic memory effects, demonstrate that the exchange bias should be attributed to the exchange interaction between ferromagnetic clusters and the antiferromagnetic host in the Ni38.8Co2.9Mn37.9Ti20.4 thin film at low temperature. The local Mn-Co-Mn configuration provides the ferromagnetic contribution, which is formed in the antiferromagnetic Heusler main phase due to the small amount of Co-substitution for Ni. The achievement of the large exchange bias effect in the Ni38.8Co2.9Mn37.9Ti20.4 thin film is a significant addition to the existing multiple magneto-responsive effects in all-3d-metal Ni-Mn-based Heusler systems. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Recently, long noncoding RNAs (lncRNAs) have attracted much attention for their roles in tumor progression. The aim of this study was to investigate the exact role of lncRNA DLX6 antisense RNA 1 (DLX6-AS1) in the development of thyroid cancer (TC), and to explore the underlying mechanism. PATIENTS AND METHODS: DLX6-AS1 expression in both TC cells and tissue samples was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Moreover, transwell assay and wound healing assay were conducted. QRT-PCR and Western blot assay were used to explore the underlying mechanism. Furthermore, the function of DLX6-AS1 was identified in vivo. RESULTS: DLX6-AS1 expression level in TC tissues was significantly higher than that of the corresponding normal tissues. Moreover, TC cell migration and invasion were markedly inhibited after DLX6-AS1 was knocked down in vitro. The mRNA and protein expressions of UPF1 were both remarkably up-regulated after knockdown of DLX6-AS1. Meanwhile, the expression level of UPF1 was negatively correlated with the expression of DLX6-AS1 in TC tissues. Further more knockdown of DLX6-AS1 significantly inhibited tumor metastasis in vivo. CONCLUSIONS: Knockdown of DLX6-AS1 could inhibit TC cell migration and invasion via upregulating UPF1, which might be a potential therapeutic target in TC. [ABSTRACT FROM AUTHOR]

In this study, the peach kernel proteins were extracted and treated with alkaline proteinase to generate peach kernel protein hydrolysate (PKH), which showed angiotensin converting enzyme (ACE) inhibition activity. The hydrolysate was separated into four fractions and their anti-ACE activities were investigated. Our results showed that all PKHs had anti-ACE activity, and the lowest molecular weight fraction PKH4 had the highest ACE inhibitory activity. Lineweaver–Burk plots illustrated that the inhibition types of PKH3 and PKH4 were non-competitive. The Ki of PKH4 was lower than Ki of PKH3; suggesting PKH4 had high affinity to ACE. Amino acid composition analysis showed that the best anti-ACE peptide PKH4 possessed high levels of hydrophobic amino acids, branched-chain amino acids, and aromatic amino acids. In summary, our findings demonstrated that high anti-ACE activity is negatively related to the size of the PKHs and possibly the composition of amino acids, and the PKH4 was the best ACE inhibitor. Further, peach kernel peptides can be developed as a functional food for patients with hypertension. [ABSTRACT FROM AUTHOR]

Dipolarization fronts (DFs) are important for energy conversion, particle acceleration, and flux transport in the magnetotail. The partition of energy conversion between ions and electrons and the energy dissipation at DFs are not well understood. In this paper, we present a statistical study of energy conversion and dissipation of 122 DFs observed by Magnetospheric Multiscale mission in the magnetotail. Statistically, electromagnetic energy transfers to plasma at DF. The released energy is mainly transferred to ions rather than electrons. On average, ions gain energy across the whole DF, while electrons gain energy at the leading part but lose energy at the trailing part of DFs. Joule dissipation J · (E+ve × B) can be either positive or negative at DFs, and its average value is very small. The kinetic energy dissipation parameter Pi − D does not exhibit clear signatures at the DFs; hence, it is not suitable for quantifying the energy dissipation at DF. Key Points: Statistical study of the energy conversion and dissipation at DFs observed by MMSElectromagnetic energy released at DF mainly goes to heat and accelerate ionsAverage Joule dissipation across DF is very small, and the parameter Pi − D is not suitable for quantifying the energy dissipation at DF [ABSTRACT FROM AUTHOR]

Through phase‐space analysis of Dumond diagrams for a flat Bragg crystal, a single bent Laue crystal and a monochromator consisting of double‐bent Laue crystals, this work shows that it is possible to match the flat Bragg crystal to both the single‐crystal and double‐crystal Laue monochromators. The matched system has the advantage that the phase space of the bent crystal's output beam is much larger than that of the flat crystal, making the combined system stable. Here it is suggested that such a matched system can be used at synchrotron facilities to realize X‐ray dark‐field imaging, analyzer‐based imaging and diffraction‐enhanced imaging at beamlines using double‐Laue monochromators. [ABSTRACT FROM AUTHOR]

In this paper, the propagation of the shear horizontal wave (SH-wave) in the single piezoelectric layer and periodically layered piezoelectric structure is studied. Both the dispersion equation and transmission coefficients are derived to reveal the wave behavior of the corresponding structures when the piezoelectricity is ignored or the electrical circuit is open and closed. The zero-order mode of the piezoelectricity-ignored single plate is not dispersive and every higher order mode is dispersive with a cut-off frequency. Same features are found for the electrically open and closed cases except that the zero-order mode of the latter case is no more non-dispersive. The pass bands of the piezoelectricity-ignored periodically layered structure appear when the normalized frequency is an even integer under the normal incidence, and new stop bands will appear from the pass bands as the incident angle increases. The same features are observed for the band gaps of the electrically open and closed cases except that the zero-order mode of the latter case is dispersive. The stop bands of the periodic structure will change in a cycle as the geometric ratio increases from zero to one. [ABSTRACT FROM AUTHOR]

We study the temperature and pressure dependence of phase evolution in the 0.5MgO-0.5Y2O3 nanocomposite system using a diamond anvil apparatus in conjunction with in situ synchrotron energy dispersive x-ray diffraction at 7 GPa hydrostatic pressure. At (298 K, 7.0 GPa), structural transformations in the Y2O3 phase are observed, giving rise to the co-existence of its cubic, hexagonal, and monoclinic polymorphs together with cubic MgO. An increase in temperature to 1273 K causes the crystallinity of the Y2O3 hexagonal and monoclinic phases to increase. Isothermal and isobaric hold at (1273 K, 7.0 GPa) for 60 min results in yttrium dissolution in cubic MgO, causing ∼1.0% expansive volumetric lattice strain despite the large differences in the ionic radii of the cations. Cooling the nanocomposite to (298 K, 0 GPa) after a 60 min soak yields four phase co-existence among cubic MgO and cubic, hexagonal, and monoclinic Y2O3. The residual MgO unit cell volume expansion is 0.69% at 298 K, indicating solid solution formation at room temperature despite large differences in the ionic radii of Mg2+ and Y3+. The macroscopic shrinkage due to densification is 3% by volume. Thermodynamic considerations suggest that the relative molar partial volume of Y3+ in MgO is a negative quantity, indicating that the partial molar volume of Y3+ in the solid solution is smaller than its molar volume in the pure state. Aging of the nanocomposites for 240 h does not change the observed 4 phase co-existence. We propose a crystallographic model in which the observed volumetric expansion of the MgO unit cell is primarily attributed to two hydrostatic expansive strain components accompanying solid solution formation: (i) Coulomb repulsion among O2- ions in the immediate vicinity of Mg2+ vacancies, and (ii) misfit strain due to differences in ionic radii upon Y3+ substitution on Mg2+ sites. [ABSTRACT FROM AUTHOR]

Elastic and plastic strain evolution under four-point bending has been studied by synchrotron energy dispersive x-ray diffraction. Measured strain profiles across the specimen thickness showed an increasing linear elastic strain gradient under increasing four-point bending load up to ∼2 kN. The bulk elastic modulus of Ti–6Al–4V was determined as 118 GPa. The onset of plastic deformation was found to set in at a total in-plane strain of ∼0.008, both under tension and compression. Plastic deformation under bending is initiated in the vicinity of the surface and at a stress of 1100 MPa, and propagates inward, while a finite core region remains elastically deformed up to 3.67 kN loading. The onset of the plastic regime and the plastic regime itself has been verified by monitoring the line broadening of the (100) peak of α-Ti. The effective compression/tension stress-strain curve has been obtained from the scaling collapse of strain profile data taken at seven external load levels. A similar multiple load scaling collapse of the plastic strain variation has also been obtained. The level of precision in strain measurement reported herein was evaluated and found to be 1.5×10-5 or better. [ABSTRACT FROM AUTHOR]

In-plane alternating pulses of current applied with an external magnetic field that changes the strength and direction of the exchange bias are observed in NiFe/Cu/NiFe/FeMn spin valves. To provide clear evidence of this spin-polarized current for antiferromagnets incorporated in spin valves, a series of measurements was carried out to rule out the influence of Joule heating caused by the pulse. The measurements revealed that Joule heating plays a minor role in the impact of exchange bias, thus providing more convincing evidence of the spin torque exerted on the interfacial antiferromagnetic moments. [ABSTRACT FROM AUTHOR]

Al doped p-type 6H silicon carbide was irradiated by low energy electrons to create primary defects. Two deep levels at EV+0.36 eV and EV+0.81 eV were created by this irradiation. Isochronal annealing study was carried out on the electron irradiated sample to investigate the annealing out of the two primary defects and the creation of thermal annealing-induced secondary defects. Four more deep hole traps (0.45, 0.56, 0.74, and 0.71 eV above the valence band) were formed during the whole annealing process up to a temperature of 1600 °C. All the electron irradiated deep level defects were annealed out after the 1600 °C annealing. [ABSTRACT FROM AUTHOR]

A model is presented in this article to investigate the dependence of effective magnetostriction of the magnetostrictive composites on the parameters of components including the elastic modulus, permeability, and volume fraction, etc. Concentrating on the two-component magnetostrictive composites and choosing the two components to be general magnetostrictive materials, this model yields, analytically, the effective magnetostriction of composites by means of the method of complex potential. In terms of the analysis of this model, the magnetostrictive composites can be roughly divided into two kinds. One kind is that the matrix material is nonmagnetic or a material with very low magnetostriction, in which the effective magnetostriction is independent of the permeability of components. Another kind is the case in which the two components have close magnetostriction, and the effective magnetostriction of the composites generally depends on the elastic and the magnetic parameters of both components and the volume fraction. Unlike the first kind of composite, in a certain range, effective magnetostriction of this kind of composite can be improved by increasing the permeability of matrix. In addition, dependence of the effective magnetostriction on the other parameters of the components has also been discussed systematically. To evaluate the accuracy of this model, comparisons are made between the theoretical values and the experimental results published in the literature, which indicate that predictions of this model agree qualitatively with the experimental data. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Two powerful synchrotron x-ray scattering techniques for residual strain depth-profiling and tomography-like scatter-intensity profiling of materials are presented. The techniques utilize energy dispersive x-ray scattering, from a fixed microvolume, with microscanning of the specimen being used to profile its interior. The tomography-like profiles exploit scattering-cross-section variations, and can be contrast enhanced by separately monitoring scattering from different crystal structures. The strain profiling technique is shown to finely chronicle the internal strain variation over several mm of steel. Detailed strain profiling for a cantilever spring demonstrates the interplay of residual and external stresses in elastic/plastic deformation. Since surface compression, by shot peening, is a classic method to fortify against fatigue failure, the strain profile for a shot-peened, surface-toughened material is determined and discussed in terms of a simple elastic-plastic stress/ strain model. Finally the lattice strains in a WC/Co coated steel composite material are discussed. [ABSTRACT FROM AUTHOR]

Synchrotron energy dispersive x-ray diffraction is used for studying the elastic and plastic strain evolution under four-point bending. The bulk elastic modulus of Ti-6Al-4V is determined as 118 GPa and the effective compression/tension stress-strain curve is obtained along with a similar multiple load scaling collapse of the plastic strain variation.