The metallic interface between insulating LaAlO3 and SrTiO3 opens up the field of oxide electronics. With more than a decade of researches on this heterostructure, the origin of the interfacial ...conductivity, however, remains unsettled. Here we resolve this long-standing puzzle by atomic-scale observation of electron-gas formation for screening hidden lattice instabilities, rejuvenated near the interface by epitaxial strain. Using atomic-resolution imaging and electron spectroscopy, the generally accepted notions of polar catastrophe and cation intermixing for the metallic interface are discounted. Instead, the conductivity onset at the critical thickness of 4-unit cell LaAlO3 on SrTiO3 substrate is accompanied with head-to-head ferroelectric-like polarizations across the interface due to strain-rejuvenated ferroelectric-like instabilities in the materials. The divergent depolarization fields of the head-to-head polarizations cast the interface into an electron reservoir, forming screening electron gas in SrTiO3 with LaAlO3 hosting complementary localized holes. The ferroelectric-like polarizations and electron-hole juxtaposition reveal the cooperative nature of metallic LaAlO3/SrTiO3.
The distribution and fate of dichlorodiphenyltrichloroethanes (DDTs) and hexachlorocyclohexanes (HCHs) in sediments from the East China Sea (ECS) and the Yellow Sea (YS) were compared and studied in ...this work. The ECS has directly large river‐dominated inputs of sediment‐associated pollutants while the YS does not. The results indicated that these mud deposits of the YS and ECS were the sinks of land‐originated DDTs and HCHs. The consistence of these OCP species and total organic carbon (TOC) and the sediment grain size in the YS indicated that the shelf mud depositional process was the dominant factor in controlling the distribution and fate of these organic compounds under the more homogeneous and hydrodynamic‐based sedimentary conditions of the YS. The distribution of these chemicals in the coastal ECS, however, showed a much different pattern where the concentrations of DDTs and HCHs decreased with distance from the coast, and the correlations between DDTs and HCHs with TOC were very poor. This indicates that the continuous transferring of organochlorine pesticides (OCPs) into the coastal ECS by the direct riverine inputs and surface runoffs play a key role on the occurrence and fate of OCPs within this more heterogeneous environmental system.
The issue, composition dependence of glass-forming ability (GFA) in metallic glasses (MG), has been investigated by systematic experimental measurements coupled with theoretical calculations in Cu-Zr ...and Ni-Nb alloy systems. It is found that the atomic-level packing efficiency strongly relates to their GFA. The best GFA is located at the largest difference in the packing efficiency of the solute-centered clusters between the glassy and crystal alloys in both MG systems. This work provides an understanding of GFA from atomic level and will shed light on the development of new MGs with larger critical sizes.
Spin Hall effect (SHE) is studied with first-principles relativistic band calculations for platinum, which is one of the most important materials for metallic SHE and spintronics. We find that ...intrinsic spin Hall conductivity (SHC) is as large as approximately 2000(variant Planck's over 2 pi/e)(Omega cm)(-1) at low temperature and decreases down to approximately 200(variant Planck's over 2 pi/e)(Omega cm)(-1) at room temperature. It is due to the resonant contribution from the spin-orbit splitting of the doubly degenerated d bands at high-symmetry L and X points near the Fermi level. By modeling these near degeneracies by an effective Hamiltonian, we show that SHC has a peak near the Fermi energy and that the vertex correction due to impurity scattering vanishes. We therefore argue that the large SHE observed experimentally in platinum is of intrinsic nature.
Background:
Inflammatory bowel disease is a chronic immunoinflammatory disease of the gastrointestinal tract. Piperine, an alkaloid, has been reported to possess antioxidant, anti-inflammatory, ...antiapoptotic, and antiulcer potential.
Aim:
To elucidate the plausible mechanisms of action of piperine on experimental trinitrobenzenesufonic acid (TNBS)-induced colitis by assessing various biochemical, molecular, histological, and ultrastructural modifications.
Methods:
Colitis was induced in male Sprague–Dawley rats via intrarectal instillation of TNBS. Then, the rats were treated with piperine (10, 20, and 40 mg/kg, p.o.) for 14 days.
Results:
TNBS induced significant (p < 0.05) colonic damage, which was assessed by disease activity index, macroscopic score, and stool consistency. The administration of piperine (20 and 40 mg/kg) significantly inhibited (p < 0.05) these damages. Treatments with piperine (20 and 40 mg/kg) notably inhibited (p < 0.05) the TNBS-induced elevation of oxido-nitrosative stress (superoxide dismutase, glutathione, malondialdehyde, and nitric oxide), 5-hydroxytryptamine, and hydroxyproline content in the colon. Furthermore, colonic inducible nitric oxide synthase (iNOs), tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β, IL-6, interferon-gamma, and cyclooxygenase-2 (COX-2) messenger RNA (mRNA) expressions were upregulated after TNBS instillation and piperine (20 and 40 mg/kg) significantly attenuated (p < 0.05) these elevated mRNA expressions. TNBS decreased the expressions of tight junction (TJ) protein (claudin-1, occludin, and zonula occludens-1 (ZO-1)) and increased the expressions of proapoptotic (caspase-1) protein. These expressions were markedly inhibited (p < 0.05) by piperine treatment. Histological and ultrastructural studies of transmission electron microscopy suggested that piperine significantly ameliorated (p < 0.05) TNBS-induced colonic aberrations.
Conclusion:
Piperine ameliorated the progression of TNBS-induced colitis by modulating the nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor-alpha/nuclear factor-kappa B signaling pathway, thus inhibiting the overexpression of proinflammatory cytokines (TNF-α and IL’s), COX-2, iNOs, oxido-nitrosative stress, and proapoptotic proteins (caspase-1) that may improve the expression of TJ protein (claudin-1, occludin, and ZO-1).
Chronic stress is a risk factor for a variety of physiological disorders because of its increased activation of the hypothalamic-pituitary-adrenal (HPA) axis; however, it is difficult to reveal ...environmental and genetic effects contributing to long-term HPA activity because of the complexity of chronic stress. The hair cortisol concentration (HCC) can be used to reflect the accumulation of HPA axis activity over time. Some studies suggest that the HCC might be associated with the protein concentration (PC) in the hair shaft; however, no studies have revealed a dynamic relationship between them. In the present study, 1,086 hair samples from 418 Holstein cows were collected, and the effects of environmental factors on HCC, PC, and ratio of HCC to PC (HCCP) were studied. Subsequently, regression analysis and curve fitting were used to identify for better-performing indicators of chronic stress. Additionally, univariate and bivariate genetic evaluation were used to estimate the genetic components of cortisol traits and genotype by environment interactions (G × E) under different environmental and physiological states. The results showed that HCC and PC are significantly affected by hair color, sampling year, and season, whereas HCCP is not influenced by hair color. Adjusted PC and HCCP, where confounding effects are excluded, were moderately related with chronic stress indicators. Moderate to high heritabilities were obtained for HCC (0.347 and 0.390 for winter and summer, respectively), PC (0.402 and 0.495 for winter and summer, respectively) and HCCP (0.289 and 0.460 for winter and summer, respectively) when animals in the same season were evaluated. A moderate G × E interaction was detected in this study, as indicated by the low or negative genetic correlation for the same cortisol trait in different environments (e.g. heat stress condition and thermoneutral condition). In conclusion, HCCP is not affected by hair color compared with the other 2 traits; thus, it has potential as an indicator of chronic stress. Hair cortisol traits could monitor stress response process in cattle, as well as provide a better understanding of genetic mechanism for long-term HPA activity.
Purpose
Parathyroid hormone (PTH) concentrations are routinely measured in the diagnosis and management of bone and kidney diseases, but reference ranges can be overestimated if determined in ...otherwise healthy individuals for whom vitamin D deficiency was not evaluated. We establish PTH reference ranges in apparently healthy, normocalcemic, normophosphatemic individuals categorized by 25-hydroxyvitamin D (25(OH)D) status using the Elecsys
®
PTH (
cobas e
601) and Elecsys
®
Vitamin D total II electrochemiluminescence immunoassays (
cobas e
411).
Methods
This prospective, non-interventional study measured PTH in serum from 653 apparently healthy adults 56.7% female; 68.2% white/Caucasian; 28.6% African American; median age 44 years (range 21–83) from three diverse geographic sites across the USA during summer and winter months. Subjects were classified by concomitant vitamin D sufficiency (≥ 30 ng/mL), insufficiency (> 20 to < 30 ng/mL) or deficiency (≤ 20 ng/mL).
Results
In vitamin D sufficiency, median PTH was 31.9 pg/mL range (2.5th–97.5th percentile) 17.9–58.6 compared with 35.5 pg/mL (17.0–60.4) for insufficiency, and 39.8 pg/mL (19.5–86.4) for deficiency. A significant inverse relationship was found between PTH and 25(OH)D (
P
< 0.001). After accounting for vitamin D, potential effects of race or season as covariates were relatively small or absent.
Conclusions
Upper reference limits (URL) for PTH in vitamin D sufficiency/insufficiency were similar and lower than current values. Clinically important PTH elevations were observed in vitamin D deficiency, where revised reference ranges with a higher URL may be appropriate. These data may help to distinguish vitamin D-related PTH elevations from other causes e.g., primary (normocalcemic) or secondary hyperparathyroidism.
Recently, the tensor network states (TNS) methods have proven to be very powerful tools to investigate the strongly correlated many-particle physics in one and two dimensions. The implementation of ...TNS methods depends heavily on the operations of tensors, including contraction, permutation, reshaping tensors, SVD and so on. Unfortunately, the most popular computer languages for scientific computation, such as Fortran and C/C++ do not have a standard library for such operations, and therefore make the coding of TNS very tedious. We develop a Fortran2003 package that includes all kinds of basic tensor operations designed for TNS. It is user-friendly and flexible for different forms of TNS, and therefore greatly simplifies the coding work for the TNS methods.
Program Title: TNSP
Program Files doi:http://dx.doi.org/10.17632/fgggdbrdnx.1
Licensing provisions: GNU General Public License version 3
Programming language: Fortran2003
External routines: BLAS, LAPACK, ARPACK
Nature of problem: The implementation of Tensor Network State (TNS) methods depends heavily on the operations of tensors. Unfortunately, the most popular computer languages for scientific computation, such as Fortran and C/C++ do not have a standard library for such operations, and therefore make the coding of TNS very tedious.
Solution method: We develop a Fortran2003 package that includes all kinds of basic tensor operations designed for TNS, which greatly simplifies the coding work for the TNS methods.
Additional comments including Restrictions and Unusual features: A gcc-4.8.4 or later version is required to compile the code.
The cooling rate has a strong influence on the volume fraction, size and distribution of primary α phase of TA15 titanium alloy, which play a decisive role in the properties of the material. Thus, ...the purpose of this paper is to quantitatively investigate the effect rules of the cooling rate on the primary α phase of TA15 titanium alloy by the α/β heat treatment experiment and the mathematical modeling based on a diffusion model. The obtained results show that: (1) the final volume fraction and size of the primary α phase both increase due to more growth time of the primary α phase resulting from the decrease of the cooling rate; (2) the growth rate of primary α phase increases with cooling rate because of the larger supersaturation under higher cooling rate, and the growth rate increases first and then decreases at a certain cooling rate; and (3) the final size distribution of the primary α particles becomes more uniform with the decrease of cooling rate.
► The volume fraction of primary α phase of TA15 alloy is sensitive to cooling rate. ► The growth rate of primary α phase increases with the increase of cooling rate. ► Under similar conditions, TA15 alloy produces less primary α phase than Ti–6Al–4V. ► The particle size distribution becomes more uniform with decreasing cooling rate.
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