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Achieving diffraction-limited performance in fourth-generation synchrotron radiation sources demands monochromator crystals that can preserve the wavefront across an unprecedented extensive range. There is an urgent need for techniques of absolute crystal diffraction wavefront measurement. At the Beijing Synchrotron Radiation Facility (BSRF), a novel edge scan wavefront metrology technique has been developed. This technique employs a double-edge tracking method, making diffraction-limited level absolute crystal diffraction wavefront measurement a reality. The results demonstrate an equivalent diffraction surface slope error below 70 nrad (corresponding to a wavefront phase error of 4.57% λ) r.m.s. within a nearly 6 mm range for a flat crystal in the crystal surface coordinate. The double-edge structure contributes to exceptional measurement precision for slope error reproducibility, achieving levels below 15 nrad (phase error reproducibility < λ/100) even at a first-generation synchrotron radiation source. Currently, the measurement termed double-edge scan (DES) has already been regarded as a critical feedback mechanism in the fabrication of next-generation crystals.

The availability of soil phosphorus (P), a crucial nutrient influencing plant productivity and ecosystem function, is impacted by continuously increasing nitrogen (N) enrichment, which changes the soil P cycle. The effect of varying forms of N input on soil P dynamics in P-limited karst grassland ecosystems remains unclear. To address this knowledge gap, we conducted a greenhouse experiment to explore the effects of various forms of N addition [Ca(NO3)2, NH4Cl, NH4NO3, Urea] on soil P fractions in these ecosystems, applying two levels (N1: 50 mg N kg−1soil, N2: 100 mg N kg−1soil) of N input in two soils (yellow soil, limestone soil). Results indicated that P fractions in both soil types were significantly affected by N additions, with yellow soil demonstrating a higher sensitivity to these additions, and this effect was strongly modulated by the form and level of N added. High N addition, rather than low N, significantly affect the P fractions in both soil types. Specially, except for Ca(NO3)2, high N addition significantly increased the available P in both soils, following the order: Urea and NH4NO3 > NH4Cl > Ca(NO3)2, and decreased NaHCO3-Pi in both soils. High N addition also significantly reduced NaOH-Po and C.HCl-Po fractions in yellow soil. Additionally, the response of root biomass and alkaline phosphatase activity in both soils to N input paralleled the trends observed in the available P fractions. Notably, changes in soil available P were strongly correlated with plant root biomass and soil alkaline phosphatase activity. Our study highlights that the N addition form significantly influences soil P availability, which is closely tied to plant root biomass and alkaline phosphatase activity. This finding underscores the importance of considering N input form to boost soil fertility and promote sustainable agriculture.

The stoichiometry of senesced leaves is pivotal in nutrient cycling and can be significantly influenced by soil salinization, a rising global issue threatening the functionality of ecosystems. However, the impacts of soil salinization on senesced leaf stoichiometry are not fully understood. In this study, we conducted a pot experiment with varying soil salt concentrations to examine their influence on the concentrations and stoichiometric ratios of nitrogen (N), phosphorus (P), sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), and zinc (Zn) in the senesced leaves of Suaeda glauca (Bunge). Compared to the control group, salt treatments significantly enhanced Na concentration while diminishing the concentrations of K, Ca, Mg, Zn, N, and P. Interestingly, as salinity levels escalated, N concentration maintained stability, whereas P concentration exhibited an increasing trend. Moreover, K, Ca, and Mg significantly declined as salt levels rose. Salt treatments brought about significant changes in stoichiometric ratios, with the N:P, K:Na, N:Na, N:Mg, and Ca : Mg ratios dropping and the N:Ca and N:K ratios rising, illustrating the varying nutrient coupling cycles under different salt conditions. These findings shed light on the plasticity of stoichiometric traits in S. glauca senesced leaves in response to soil salinization shifts, which could potentially offer insights into nutrient cycling reactions to soil salinization.

A method to optimize the notches of water-cooled white-beam mirrors over the entire photon energy range is proposed. A theoretical method is used to quantitatively evaluate the influence of the thermal load on the thermal deformation of a mirror. The result of theoretical calculations and finite-element analysis are consistent, which proves the feasibility of the method. The root mean square of the curvatures of the thermal deformation of the white-beam mirror over the entire photon energy range can be minimized. This method greatly simplifies the design work of water-cooled white-beam mirrors.

The influence of the X-ray mirror errors on the performance of the beamline increases as the X-ray beam’s coherence improves in advanced light sources. The spatial dispersion of the X-ray beam is crucial for spatial resolution and field of view. However, selecting the appropriate merit function for expressing light distribution and identifying its relationship to optical error is very important in beamline design. We develop a high-efficiency wave-optics simulation platform and a deterministic analysis model to address this issue. The simulation experiments evaluated merit functions, including Strehl ratio, root-mean-square spot size, and encircled energy radius. We proved that the encircled energy radius is a good metric of the x-ray beam spatial dispersion, which matches the results of the Church-Takacs theory. In addition, it is found that limiting the contribution of the low frequency (wavelength>110L) error is effective for specifying the requirements of X-ray mirrors.

Abstract Background Ferroptosis is a recently recognized non-apoptotic cell death that is distinct from the apoptosis, necroptosis and pyroptosis. Considerable studies have demonstrated ferroptosis is involved in the biological process of various cancers. However, the role of ferroptosis in esophageal adenocarcinoma (EAC) remains unclear. This study aims to explore the ferroptosis-related genes (FRG) expression profiles and their prognostic values in EAC. Methods The FRG data and clinical information were downloaded from The Cancer Genome Atlas (TCGA) database. Univariate and multivariate cox regressions were used to identify the prognostic FRG, and the predictive ROC model was established using the independent risk factors. GO and KEGG enrichment analyses were performed to investigate the bioinformatics functions of significantly different genes (SDG) of ferroptosis. Additionally, the correlations of ferroptosis and immune cells were assessed through the single-sample gene set enrichment analysis (ssGSEA) and TIMER database. Finally, SDG were verified in clinical EAC specimens and normal esophageal mucosal tissues. Results Twenty-eight significantly different FRG were screened from 78 EAC and 9 normal tissues. Enrichment analyses showed these SDG were mainly related to the iron-related pathways and metabolisms of ferroptosis. Gene network demonstrated the TP53, G6PD, NFE2L2 and PTGS2 were the hub genes in the biology of ferroptosis. Cox regression analyses demonstrated four FRG (CARS1, GCLM, GLS2 and EMC2) had prognostic values for overall survival (OS) (all P

Abstract Background Several studies have demonstrated autophagy was involved in the process of esophageal adenocarcinoma (EAC). The aim of this study was to explore autophagy-related genes (ARGs) correlated with overall survival (OS) in EAC patients. Methods Expressions of ARGs in EAC and normal samples were downloaded from TCGA database. GO and KEGG enrichment analyses were used to investigate the ARGs bioinformatics functions. Univariate and multivariate cox regressions were performed to identify prognostic ARGs and the independent risk factors. ROC curve was established to evaluate the feasibility to predict the prognosis. Finally, the correlations between ARGs and clinical features were further explored. In addition, significantly different ARGs were verified in EAC specimens and normal esophageal mucosal tissues. Results Thirty significantly different ARGs were selected from EAC and normal tissues. Functional enrichments showed these ARGs were mainly related apoptosis. Multivariate cox regression analyses demonstrated eight ARGs were significantly associated with OS. Among these eight genes, BECN1 (HR = 0.321, P = 0.046), DAPK1 (HR = 0.636, P = 0.025) and CAPN1 (HR = 0.395, P = 0.004) played protective roles in survival. Gender (HR = 0.225, P = 0.032), stage (HR = 5.841, P = 0.008) and risk score (HR = 1.131, P < 0.001) were independent prognostic risk factors. ROC curves showed better efficacy to predict survival using the risk score. Additionally, we found BECN1, DAPK1, VAMP7 and SIRT1 genes were correlated significantly with survival status, gender, primary tumor and tumor stage (all P < 0.05). The experimental results confirmed the BIRC5 was overexpressed and the ITPR1, PRKN were downregulated in the EAC tissues compared with the normal esophageal mucosal tissues (all P < 0.05). Conclusion Our findings suggested that autophagy was involved in the process of EAC. Several ARGs probably could serve as diagnostic and prognostic biomarkers and may help facilitate therapeutic targets in EAC patients.

Background: Esophageal cancer is one of the most leading and lethal malignancies. Glycolysis and the tumor microenvironment (TME) are responsible for cancer progressions. We aimed to study the relationships between glycolysis, TME, and therapeutic response in esophageal adenocarcinoma (EAC).Materials and Methods: We used the ESTIMATE algorithm to divide EAC patients into ESTIMATE high and ESTIMATE low groups based on the gene expression data downloaded from TCGA. Weighted gene co-expression network analysis (WGCNA) and Gene Set Enrichment Analysis (GSEA) were performed to identify different glycolytic genes in the TME between the two groups. The prognostic gene signature for overall survival (OS) was established through Cox regression analysis. Impacts of glycolytic genes on immune cells were assessed and validated. Next, we conducted the glycolytic gene mutation analysis and drug therapeutic response analysis between the two groups. Finally, the GEO database was employed to validate the impact of glycolysis on TME in patients with EAC.Results: A total of 78 EAC patients with gene expression profiles and clinical information were included for analysis. Functional enrichment results showed that the genes between ESTIMATE high and ESTIMATE low groups (N = 39, respectively) were strongly related with glycolytic and ATP/ADP metabolic pathways. Patients in the low-risk group had probabilities to survive longer than those in the high-risk group (p < 0.001). Glycolytic genes had significant impacts on the components of immune cells in TME, especially on the T-cells and dendritic cells. In the high-risk group, the most common mutant genes were TP53 and TTN, and the most frequent mutation type was missense mutation. Glycolysis significantly influenced drug sensitivity, and high tumor mutation burden (TMB) was associated with better immunotherapeutic response. GEO results confirmed that glycolysis had significant impacts on immune cell contents in TME.Conclusion: We performed a comprehensive study of glycolysis and TME and demonstrated that glycolysis could influence the microenvironment and drug therapeutic response in EAC. Evaluation of the glycolysis pattern could help identify the individualized therapeutic regime.

The focusing mirror is one of the most significant optical components in the synchrotron radiation facilities, it forms a spot at the level of submicron on samples. Generally, the desired surface is in the shape of an ellipse that can be realized by mechanical bending. However, the gravity of mirrors, a non-negligible factor, affects the accuracy of the elliptic surface. As a result, optimizing the width of mirrors is the essential method to compensate the gravity. The methodology for the optimization, considering the influence of bending moments and gravity, is proposed. The conclusion indicates that this method is correct and highly efficient comparing with the existing results.

0.3 mol% platinum loaded g-C _3 N _4 sample was prepared by photoreduction method to study the long-term stability of photocatalysts. For the first time, we have discovered the oriented attachment (OA) mechanism growth of Pt nanoparticles on g-C _3 N _4 solid surface, which is completely different from Ostwald ripening (OR) or particle migration and coalescence (PMC) that previously reported. The Pt nanoparticles perform Brownian motion on the surface of g-C _3 N _4 support under the collision of liquid molecules, then two or more nanoparticles attach together via the crystallographic orientation to construct larger ones. Al _2 O _3 film prepared by atomic layer depositon was introduced to inhibit the Brownian motion of Pt nanoparticles. It is found that as the increase of the Al _2 O _3 growth cycles, the photocatalytic hydrogen production of Pt/g-C _3 N _4 coated by Al _2 O _3 increase from 1.14 mmolg ^−1 h ^−1 to 2.08 mmolg ^−1 h ^−1 and then decrease to 1.4 mmolg ^−1 h ^−1 , and the apparent quantum efficiency (QE) also increase from 1.2% to 2.1% and then decrease to 1.4%. Meanwhile, the long-term stability of photocatalyst always increases. This work has revealed new pathway of photocatalytic nanoparticle growth on solid surface and proposed the method to prevent it.

Silver sulfide, cadmium sulfide and nickel (Ag _2 S/CdS/Ni) ternary nanostructures were fabricated by a two step process and characterized by x-ray powder diffraction, transmission electron microscopy, and UV–vis diffuse reflection spectroscopy. The photocatalytic hydrogen production activity of ternary nanostructures and reference samples were evaluated using triethanolamine (TEOA) as sacrificial reagent in water under visible-light illumination ( λ ≥ 420 nm). The result shows Ag _2 S/CdS/Ni nanostructures exhibited a high visible light photocatalytic H _2 evolution rate of 1.54 mmolh ^−1 g ^−1 , which was 4.6 times and 1.4 times higher than that of 1.2% mol Ag _2 S/CdS and Ni/CdS. The degree of photocorrosion of CdS were employed to study the photogenerated carriers transfer route by measuring and comparing the concentration of Cd ^2+ in the solution of the photocorrosion experiments in a nonsacrificial system. A long-range electric field, which is similar to the p-i-n electric field structure, was proposed to be constructed by Ni nanoparticles and Ag _2 S nanoparticles in CdS. Most of the photogenerated electrons and holes in CdS drift to the electron donor and electron acceptor respectively under the action of long-range electric field, which greatly improves the separation efficiency of photogenerated carriers and the photocatalytic H _2 production activity.

A speckle-based method for the X-ray crystal diffraction wavefront measurement is implemented, and the slope errors of channel-cut crystals with different surface characteristics are measured. The method uses a speckle scanning technique generated by a scattering membrane translated using a piezo motor to infer the deflection of X-rays from the crystals. The method provides a high angular sensitivity of the channel-cut crystal slopes in both the tangential and sagittal directions. The experimental results show that the slope error of different cutting and etching processes ranges from 0.25 to 2.98 μrad. Furthermore, the results of wavefront deformation are brought into the beamline for simulation. This method opens up possibilities for new high-resolution applications for X-ray crystal diffraction wavefront measurement and provides feedback to crystal manufacturers to improve channel-cut fabrication.

Based on first-principles calculations, the adsorption of NO and NO2 gas molecules on the α-In2Se3 monolayer have been studied. The adsorption configuration, adsorption energy, electronic structure and charge transfer properties are investigated. It is found that the charge transfer processes of NO and NO2 adsorbed on the surface of α-In2Se3 monolayer exhibit electron donor and acceptor characteristics, respectively. After the adsorption of the molecules, the α-In2Se3 monolayers have new states near the Fermi level induced by NO and NO2, which can trigger some new effects on the conducting and optical properties of the materials, with potential benefits to gas selectivity. The present work provides new valuable results and theoretical foundation for potential applications of the In2Se3-based gas sensor.

The crystal of ZnW[O.sub.4] doped with [Co.sup.2+] was grown by the Czochralski technique and crystallographic axes, the principal coefficients of thermal expansion are discussed. The results show that inner defects such as natural cleavage or slip faces in crystal are important in the study of optical and thermal properties.

A classical iterative Lucy-Richardson (LR) inversion algorithm used for recovering particle-size distributions (PSD) from light-scattering data is proposed. The convergence of iteration is validated in the numerical simulation for three different distributions: the gamma, the log-normal, and the Rosin-Rammler. The accuracy of the inversion is checked graphically against the exact distribution with good results, even for the synthesized intensity data of a signal-noise-ratio smaller than 20 dB. Finally, an experiment with linear charge coupled device as the detector is carried out, and the PSD is recovered successfully by the LR inversion method. [ABSTRACT FROM AUTHOR]

Crystals of NaLa(WO4)2 : Ho3+ were grown by the Czochralski method. The spectroscopic properties have been investigated at room temperature. Intensity parameters, radiative lifetimes and branching ratios have been calculated in the framework of Judd-Ofelt theory. The luminescence spectra measured under 450 nm pumping are dominated by a strong green emission in the 550 nm region connected with the 5S2 + 5F4 - 5I8 transition. The stimulated emission cross-section for this transition was estimated. The luminescence decay curve of the 5S2 + 5F4 level was also measured at room temperature. [ABSTRACT FROM AUTHOR]

Foot-and-mouth disease virus (FMDV) infection is responsible for the heavy economic losses in stockbreeding each year. Because of the limited effectiveness of existing vaccines and antiviral drugs, the development of new strategies is needed. RNA interference (RNAi) is an effective means of suppressing virus replication in vitro. Here we demonstrate that treatment with recombinant, replication-defective human adenovirus type 5 (Ad5) expressing short-hairpin RNAs (shRNAs) directed against either structural protein 1D (Ad5-NT21) or polymerase 3D (Ad5-POL) of FMDV totally protects swine IBRS-2 cells from homologous FMDV infection, whereas only Ad5-POL inhibits heterologous FMDV replication. Moreover, delivery of these shRNAs significantly reduces the susceptibility of guinea pigs and swine to FMDV infection. Three of five guinea pigs inoculated with 106 PFU of Ad5-POL and challenged 24 h later with 50 50% infectious doses (ID50) of homologous virus were protected from the major clinical manifestation of disease: the appearance of vesicles on the feet. Two of three swine inoculated with an Ad5-NT21-Ad5-POL mixture containing 2 x 109 PFU each and challenged 24 h later with 100 ID50 of homologous virus were protected from the major clinical disease, but treatment with a higher dose of adenovirus mixture cannot promote protection of animals. The inhibition was rapid and specific because treatment with a control adenovirus construct (Ad5-LacZ) expressing Escherichia coli galactosidase-specific shRNA showed no marked antiviral activity. Our data highlight the in vivo potential of RNAi technology in the case of FMD [ABSTRACT FROM AUTHOR]