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Solid solution effect of minor elements on mechanical and especially thermal properties of zirconium (Zr) alloys has been underexplored in previous studies. This research delves into the electronic structure, phonon, mechanics, and thermodynamics of binary solid solution Zr alloys (introduction of Sn, Cu, Al, Ge, O, N, H, and C) using density functional theory (DFT). Micro-mechanical properties are changed after doping elements, particularly for doping H as interstitials. The H-induced increase in Poisson's ratio and decrease in shear modulus, Young's modulus, and hardness should be due to H-induced enhancement in the ductility of adjacent Zr atoms. Addition-induced thermodynamic properties are discernible for substitutional and interstitial elements. High frequencies of phonons appear in the Zr alloys with interstitial solid solution, which decreases the heat capacity of the Zr alloys. Conversely, the alloys featuring a substitutional solid solution experience negligible changes in heat capacity. Grüneisen parameter associated with anharmonic interaction is a determining factor in the thermal expansion of the Zr alloys. In low phonon frequencies (≤2 THz), the more negative contribution of Grüneisen parameter leads to the lower thermal expansion of the Zr alloys with interstitial solid solution, with respect to substitutional solid solution. Deep investigation reveals that the mode of lattice vibration in the low frequency almost remains the original transverse mode of the pure Zr for interstitial solid solution. For substitutional solid solution, the atomic layer containing doping element vibrates from transversely to longitudinally. Our work helps purposefully tune the properties of novel Zr alloys through screening and adding alloying elements.

Single-cell technologies offer unprecedented opportunities to dissect gene regulatory mechanisms in context-specific ways. Although there are computational methods for extracting gene regulatory relationships from scRNA-seq and scATAC-seq data, the data integration problem, essential for accurate cell type identification, has been mostly treated as a standalone challenge. Here we present scTIE, a unified method that integrates temporal multimodal data and infers regulatory relationships predictive of cellular state changes. scTIE uses an autoencoder to embed cells from all time points into a common space by using iterative optimal transport, followed by extracting interpretable information to predict cell trajectories. Using a variety of synthetic and real temporal multimodal data sets, we show scTIE achieves effective data integration while preserving more biological signals than existing methods, particularly in the presence of batch effects and noise. Furthermore, on the exemplar multiome data set we generated from differentiating mouse embryonic stem cells over time, we show scTIE captures regulatory elements highly predictive of cell transition probabilities, providing new potentials to understand the regulatory landscape driving developmental processes.

• Ultra-slow coarsening rates of the nanoparticles from 2.47 × 10–29 to 5.74 × 10–29 m3 s–1 were found in the chemically complex high-entropy alloys (HEAs) at 800 °C. • Excellent thermally stable structures with pristine "L1 2 + FCC" were obtained even upon long-term aging at 800°C • The stacking fault-mediated deformation enabled a superior high work-hardening rate and an anomalous improvement in yield strength at elevated temperatures. The precipitate morphologies, coarsening kinetics, elemental partitioning behaviors, grain structures, and tensile properties were explored in detail for L1 2 -strengthened Ni 39.9 Co 20 Fe 15 Cr 15 Al 6 Ti 4– x Nb x B 0.1 (x = 0 at.%, 2 at.%, and 4 at.%) high-entropy alloys (HEAs). By substituting Ti with Nb, the spheroidal-to-cuboidal precipitate morphological transition, increase in the coarsening kinetics, and phase decomposition upon aging at 800 °C occurred. The excessive addition of Nb brings about the grain boundary precipitation of an Nb-rich phase along with the phase decomposition from the L1 2 to lamellar-structured D0 19 phase upon the long-term aging duration. By partially substituting Ti with Nb, the chemically complex and thermally stable L1 2 phase with a composition of (Ni 58.8 Co 9.8 Fe 2.7)(Al 12.7 Ti 5.8 Nb 7.5 Cr 2.3) ensures the stable phase structure and clean grain boundaries, which guarantees the superb high-temperature mechanical properties (791 ± 7 MPa for yielding and 1013 ± 11 MPa for failure) at 700 °C. Stacking faults (SFs) were observed to prevail during the plastic deformation, offering a high work-hardening capability at 700 °C. An anomalous rise in the yield strength at 800 °C was found, which could be ascribed to the multi-layered super-partial dislocations with a cross-slip configuration within the L1 2 particles. [Display omitted] [ABSTRACT FROM AUTHOR]

The joining of dissimilar materials to fabricate lightweight components of thin-walled structures for aerospace applications has garnered significant interest. A pioneering technique has been proposed to achieve an optimal interfacial microstructure and fillet of brazed joints. This technique involves a layer of Al deposited on the surface of TiAl base metal, which aids in the brazing process of the thin-walled structure comprising TiAl and GH3536 alloys. Notably, the addition of the Al layer has a significant impact on the spreading area of molten brazing filler metal, the size of the fillet, and the interfacial microstructure evolution. Consequently, these factors contribute to a substantial increase in the load-bearing capacity of the structure. A comprehensive analysis and discussion are conducted to explore the impact of the Al layer on both the interfacial microstructure and mechanical performance. Under the brazing parameters of 1040 °C/5 min, the peak tensile load reaches a peak value of 362 N, which is 100% higher compared to the joints without Al layer. It is worth noting that fracture occurred in the GH3536 foil after undergoing tensile testing. The dimension of fillet can be controlled through the in-situ synthesis Al2TiO5ceramic phase on the surface of TiAl alloy. This research offers valuable insights into the production of engineered biomimetic materials and devices, specifically focusing on honeycomb-inspired structures.

The mechanical properties of honeycomb sandwich structures are improved using topological-reinforcement and material-strengthening. This study introduces a novel type of TiAl/GH3536 hetero-honeycomb sandwich structure, called the enhanced honeycomb sandwich structure, which boasts a relative density of core range of 3.2%–21.2%. The enhanced honeycomb sandwich structure is designed and fabricated through a vacuum-brazing method using BNi-2 brazing filler metal. The microstructure and out-of-plane compression behavior of both the as-brazed and original honeycomb cores are experimentally and analytically investigated. The study establishes good correlations between analytical predictions and experimental results. The results highlight the sensitivity of the mechanical properties of the enhanced honeycomb cores to the unit-cell size and parent–alloy properties, specifically inelastic buckling, and elastic modulus. The compressive characteristics of the enhanced honeycomb sandwich structures were thoroughly examined, and it was determined that the efficient filling of gaps between the honeycomb core walls with liquid BNi-2 brazing filler metal, coupled with the optimal core structure, resulted in the precipitation of mesh-like Mo-boride compounds within the GH3536 parent material. This resulted in a significant increase in the compressive strength and elastic modulus, by up to 57.4% and 26.3%, respectively. The combination of topological-reinforcement and material-strengthening provided a way to achieve lightweight sandwich structures with high specific strengths and low densities, which is important on the fabrication of engineering bioinspired materials and devices designed based on honeycomb structures.

This study aimed to investigate the effects of time access to post-hatch feeding on the growth performance, hormone secretion, intestinal morphology, and intestinal microbiota structure of broilers. A total of 900 broilers were randomly allocated to 3 treatment groups, with 6 replicates of 50 broilers each. The 3 treatments were: immediate feeding (Group 2 h), delayed access to feed for 24 h (Group 24 h), and delayed access to feed for 48 h (Group 48 h). The experiment lasted for 50 d. Results revealed that Group 2 h had a higher average daily gain (ADG) and average daily feed intake (ADFI) as well as a lower feed-to-gain ratio (F/G) than Group 48 h during the starter period (P< 0.05). Compared with Group 48 h, broilers in Group 2 h exhibited significantly elevated villus height (VH) and villus height to crypt depth ratio (VH: CD) in the duodenum, increased Occludin, and Claudin-1 mRNA expression in the jejunum but decreased crypt depth (CD) in the duodenum at 50 d (P< 0.05). Meanwhile, broilers in Groups 2 h and 24 h had increased glycogen (Gn) and protein (Pro) levels in breast muscle and TG levels in the liver, as well as a higher concentration of serum T3, T4, and IGF-1 compared with Group 48 h at 21 d (P< 0.05). Besides, intestinal microbiota consisted primarily of Firmicutes, Bacteroidetes, and Proteobacteriaat the phylum level at 21 d and 50 d; at the genus level, broilers in Group 2 h displayed significantly reduced abundance of Escherichiaat 21 d and Bacteroidesat 50 d compared with Group 48 h (P< 0.05). Collectively, these findings signal that early post-hatch feeding measures, especially at 21 d, improve hormone secretion, intestinal morphology, and the growth performance of broilers by enhancing intestinal health and modulating the intestinal microbiota.

With the recent increase in study sample sizes in human genetics, there has been growing interest in inferring historical population demography from genomic variation data. Here, we present an efficient inference method that can scale up to very large samples, with tens or hundreds of thousands of individuals. Specifically, by utilizing analytic results on the expected frequency spectrum under the coalescent and by leveraging the technique of automatic differentiation, which allows us to compute gradients exactly, we develop a very efficient algorithm to infer piecewise-exponential models of the historical effective population size from the distribution of sample allele frequencies. Our method is orders of magnitude faster than previous demographic inference methods based on the frequency spectrum. In addition to inferring demography, our method can also accurately estimate locus-specific mutation rates. We perform extensive validation of our method on simulated data and show that it can accurately infer multiple recent epochs of rapid exponential growth, a signal that is difficult to pick up with small sample sizes. Lastly, we use our method to analyze data from recent sequencing studies, including a large-sample exome-sequencing data set of tens of thousands of individuals assayed at a few hundred genic regions.

Statistical methodologies are indispensable in data-driven scientific discoveries. In this paper, we make the first effort to understand the impact of recent statistical innovations on other scientific fields. By collecting comprehensive bibliometric data from the Web of Science database for selected statistical journals, we investigate the citation trends and compositions of citing fields over time, and we find increasing citation diversity. Furthermore, in a new setting, we apply a local clustering technique involving personalized PageRank with graph conductance for size selection to find the most relevant statistical innovation for a given external topic in other fields. Through a number of case studies, we show that the results from our citation data analysis align well with our knowledge and intuition about these external topics. Overall, we have found that the statistical theory and methods recently invented by the statistics community have made increasing impact on other scientific fields.

HIPIB irradiation into AZ31 magnesium alloy is performed at ion current density of 100-300 A/cm2 with 1 shot. The surface morphologies and surface profiles of the irradiated AZ31 magnesium alloy samples are characterized by scanning electron microscopy (SEM) and profilometer, respectively. It is found that HIPIB irradiation leads to the formation of crater in local region of irradiated samples, and crater density increases with increasing ion current density. Both the surface roughness that reflects the vertical wave of surface profile and the mean spacing of surface profile irregularities that reflects the horizontal wave of surface profile increase as ion current density increases. These results are in agreement with the SEM observation on the irradiated surface.

Firstly, with studying three typical aspects as cutting force, cutting temperature and chip breaking behavior, contrast experiments of machinability were made on hydrogenated cylindrical shell materials (2.25Cr-1Mo-0.25V), 45 steel, and stainless steel (1Cr18Ni9Ti). The experiment results show that the depth of cut ap have a larger effect on the main cutting force FZ and the cutting temperature θ than the affection of the feedrate f, for that reason, in order to reduce the main cutting force FZ and the cutting temperature θ, large feedrate situation will be better for machining work of hydrogenated cylindrical shell materials. When cutting hydrogenated cylindrical shell materials , many difficult points appearance, such as large cutting force, high cutting temperature, serious chips winding, chips difficult to break etc, which has worse machinability even than stainless steel(1Cr18Ni9Ti).

Purpose To evaluate the prevalence of diabetic retinopathy and risk factors among patients with self-reported diabetes mellitus in China.Methods The Beijing Eye Study, a population-based study on inhabitants aged 40+ years, included 4439 subjects. Fundus photographs of the worse eye from participants with self-reported diabetes were graded.Results Fundus photographs ready for evaluation and a filled out questionnaire were available for 4127 (93.0%) subjects. The prevalence of self-reported diabetes was 235/4127 (5.7%). Among the subjects with a self-reported diagnosis of diabetes, diabetic retinopathy was detected on the fundus photographs of 86 (37.1%) subjects, with macular edema in 12 (5.2%) subjects, clinically significant macular edema in 6 (2.6%) subjects, and a vision-threatening stage of the retinopathy in 12 (5.2%) subjects. Diabetic retinopathy was associated with rural region (p=0.004), longer duration of diabetes (p=0.009), use of diabetic medications (p=0.02), and lower education background (p=0.003).Conclusions Prevalence of diabetic retinopathy among Chinese patients aged 40+ years with a self-reported diagnosis of diabetes is about 37%, with a vision-threatening stage of the retinopathy detected in 5% of the subjects. About 5.7% of the adult Chinese population report on a known diagnosis of diabetes mellitus, with about 15% of these subjects knowing about the presence of diabetic retinopathy. The frequency of known diabetes mellitus is lower in rural regions than in urban regions, while diabetic retinopathy overall and macular edema among the subjects with known diabetes mellitus were significantly more common in the rural group.

Single carrageenan and combinations of carrageenan with other polysaccharides, including locust bean gum and konjak gum, are applied to form green bodies of microwave ceramics by gel-casting technique. Similar dielectric properties of the samples are achieved and compared with ceramics formed by dry pressing method.

Using density functional methods, optical properties of KTa0.5Nb0.5O3(KTN) are investigated. The imaginary part of dielectric function ε2(ω), the optical absorption coefficient I(ω) and the reflectivity R(ω) of KTN in the cubic (paraelectric) and tetragonal (ferroelectric) phases are calculated. The origin of the different behavior of the optical spectra between the two phases is discussed.

Ammonium rare earth fluorides NH4Ln3F10(Ln=Dy, Ho, Y, Er, Tm) were synthesized by a hydrothermal method. Two polymorphs, of the hexagonal β-KYb3F10and the cubic γ-KYb3F10structure types, were formed under hydrothermal conditions for most of the rare earth fluorides except NH4Dy3F10, for which only the cubic γ-phase was obtained. The crystal structures of MLn3F10(M=alkaline metal, NH+4and Ln=rare earth) show a strong correlation to the ratio of ionic radii (RM/RLn), which has been expressed in a structure phase diagram of the ionic radii of univalent and rare earth cations.

We have measured the specific heat, resistance and dc susceptibility of the mixed valence manganite La0.85K0.15MnO3 as a function of temperature. The sample shows colossal magnetoresistance effects with phase transitions at low temperature. The magnetic specific heat of this sample is proportional to the temperature coefficient of the resistance, following the Fisher-Langer relation. This suggests that the sharp drop in the transition region of the sample is due to the magnetic scattering.

AbstractElectronic structure of incipient ferroelectric CaTiO3has been studied from the full potential linearized augmented plane wave method(FLAPW). To understand the incipient ferroelectricity of CaTiO3, the total energy, the density of states, and band structure have been obtained. From the total energy analysis, we found that CaTiO3has a tendency to ferroelectricity. Like other perovskite ABO3ferroelectrics, there is a hybridization between Ti d and O p, and O 2p, which is responsible for the tendency to ferroelectricity.

AbstractElectronic structure of ferroelectric PbZr½;Ti½;O3is studied by full potential linearized augmented plane wave method. The density of states, charge density distribution and band structure have been obtained to understand the ferroelectric behavior of PbZrl/2Ti½;O3solid solution. From the density of states, we found that Pb and Ti in PbZr½;Ti½;O3play similar role with ones in pure ferroelectric PbTiO3. This is consistent with the calculation of electronic band structure. Like in other perovskite ABO3ferroelectrics, there is hybridization between Ti d and O p, which is responsible for the tendency to the ferroelectricity.

Phase equilibrium of the La–Ca–Mn–O system at 900°C in atmosphere was examined and illustrated in the form of a phase diagram. La1−xCaxMnO3forms a solid solution with two distinct perovskite structures (R3cand Pnma). A new compound La2Ca2MnO7, identified in the phase diagram, crystallizes in a rhombohedral structure (R3) with the lattice constants of a=5.62176(4), c=17.3161(2) Å. The phase regions in the La–Ca–Mn–O system were clarified based on the X-ray diffraction analysis of the samples.

The treatment of wheat straw with 2% H2O2at 50°C and pH 11.5 for 4–30h or with 2% H2O2–0.05% anthraquinone at 50°C and pH 11.5 for 4.5h resulted in the release of 79–86% of the original lignin and 77–91% of the original hemicelluloses, which contained 3.8–6.5% of associated lignins. Xylose was the major sugar constituent in all the solubilized hemicellulosic fractions, and arabinose, glucose, and galactose were present in small amounts. The isolated seven hemicellulosic samples were further characterized by Fourier transform infrared, and carbon-13 magnetic resonance spectroscopy as well as gel permeation chromatography. Comparison of these hemicellulosic fractions with those obtained by alkali extraction from wheat straw in the absence of hydrogen peroxide provided evidence of similar chemical composition and structure. The treatment by alkaline peroxide under the conditions used did not result in any significant change in the macromolecular structure of hemicelluloses.

The interaction of Cr with an Al2O3(1102) surface was studied using surface-sensitive techniques, X-ray photoelectron spectroscopy and Auger electron spectroscopy. The Cr/Al2O3interface was formed by vapour deposition of chromium on an Al2O2(1102) surface in ultra high vacuum (UHV). The present results suggest that the Cr underwent a reluctant chemical reaction with the Al2O3(1102) surface to form a complex oxide Cr-O-Al at room temperature due to competition with the Al ions for oxygen during formation of the interfacial layer. Annealing the Cr-covered sample in UHV promoted the reaction between the Cr and Al2O3substrate, forming metallic Al and Cr-O species in the interfacial layer. Chromium oxide was incorporated into the Cr overlayer, which strongly enhanced the surface oxygen anions. In contrast, metallic Al was found only at the interface which might have dissolved partially in the Cr layer as a solute or might be present in the Cr matrix as Cr-Al alloy (probably also including oxygen), depending on the temperature and composition in the thermal equilibrium state. The reactivity of Cr with Al2O3(1102) was shown to be less than that of Ti. © 1997 Elsevier Science Ltd. All rights reserved

The expression of DPP IV/CD26 was studied in epithelial cells from different regions of the human small intestine and colon. The following data were obtained: 1) DPP IV/CD26 activity was highest in ileum and jejunum, low in duodenum and not detectable in colon; 2) The amount of DPP IV, as analyzed by Western blotting, was very low in duodenum and increased up to the ileum. No DPP IV protein was detected in colon; 3) RT-PCR analysis showed the expected 315-bp product in the small intestine with the highest signal in ileum and jejunum and a low signal in duodenum; a faint PCR signal could be detected in colon. Similar data were obtained by Northern blot analysis which revealed a 3.6-kb transcript only in small intestine. It is concluded that DPP IV/CD26 gene expression in human intestine is highest in the distal small intestine, and that is regulated at the mRNA level.

In this work we have studied the interfacial reactions between chromium and an Al2O3(11-02) surface with X-ray photoelectron spectroscopy and Auger electron spectroscopy. The results reveal that, at room temperature, the interfacial reactions are dominated by the interaction of Cr atoms with the oxygen anions on the Al2O3 substrate forming a Cr–O–Al complex oxide. Annealing the Cr-covered sample to high temperature, additional interfacial reactions occur, involving the formation of chromium oxide and metallic Al, indicating the interfacial reactions have a strong temperature dependence. The results also show that the relative Auger peak-to-peak height (APPH) of the Cr LMM group peaks is very sensitive to the change of the valence band structure, therefore, it can be used as an index to identify the oxidation state of chromium at the Cr/Al2O3 interface.

High secondary electron yields (σ=14–27) from polycrystalline diamond films on Mo substrates have been reported previously. We observed that continuous exposure to an electron beam degraded the secondary yield in vacuum as a function of fluence owing to a loss of surface hydrogen. However, the hydrogen partial pressure could be adjusted such that the high secondary yield remained stable during beam exposure. We have constructed a prototype electron multiplier using these diamond films for use in ultrahigh vacuum. A gain of 0.9 × 105has been measured in a d.c. mode. Palladium, titanium and aluminum nitride have been studied for possible dynode substrate materials which might eliminate the need for hydrogen during operation. Total secondary yields as high as 50 were measured from diamond on palladium and σ was stable at 25 during heating at 700 K in vacuum. Raman spectroscopy and scanning electron microscopy showed that variations in σ from diamond films on Pd were due to differing concentrations of non-diamond carbon.

To evaluate hearing levels in Chinese young people, audiometry was carried out at a rural village in Shandong Prefecture. The subjects were 282 healthy school children and students ranging in age from 7ȁ17 y. All subjects were asked to complete a brief questionnaire on otological symptoms, personal histories and use of noisy playthings. Audiometric threshold testing was performed at the audiomeric frequencies of 0.5, 1, 2, 4 and 8 kHz. Cluster analysis was used to estimate the associations between questions in the questionnaire and hearing impairment. Fifty-six subjects (20% subjects) were excluded from the normal groups. Twenty-two ears of the excluded subjects showed 4 kHz-dip and 38 ears showed high frequency hearing loss. An increased prevalence of hearing impairment was found when compared with young Japanese (1% from the nationwide school health survey) and with young Chinese in Shandong Prefecture (0.5%). In the questionnaire, 4 questions on dizziness, head trauma, aminoglycoside administration, and suspicion of Meniere's syndrome, were included in the cluster of hearing impairment. The cause of this hearing impairment was proposed to be the potentiating effects of aminoglycoside antibiotics and exposure to noise.

The temperature dependence of the electrical resistivity and the thermoelectric power (TEP) of Bi2Sr2—xLaxCaCu2Oy (x = 0 to 0.8) samples is reported. Analysis of the electrical resistivity of the insulating samples suggests that the conduction is governed by a variable-range-hopping mechanism in the low temperature range. The linear-T behavior of the superconducting samples is consistent with the Drude model. The broad peak shift in the S–T plot of the insulating samples is explained. The results of thermoelectric power are discussed following the two-band model.

Hydrogel of poly(N-n-propylacrylamide) was prepared and its swelling dependence on temperature and pressure was investigated. Dramatic volume change of the gel with pressure and temperature was observed.

A slot-line electromagnetic energy coupler operating at 915 MHz for noninvasive diagnostic applications is described. The coupler is well matched when it is coupled to the biological tissue (VSWR < 1.5), its structure is simple and energy coupling efficiency is high.

To evaluate the effects of amlodipine-based antihypertensive combination regimen on blood pressure control and impact on cardiovascular events.