The aim of this study was to investigate the effect of Roux-en-Y gastric bypass (RYGB) on the peripheral blood microRNAs (miRNAs) of patients with type 2 diabetes mellitus (T2DM). miRNAs are small ...20- to 22-nucleotide (nt) noncoding RNAs. They constitute a novel class of gene regulators that negatively regulate gene expression at the post-transcriptional level. miRNAs play an important role in several biological processes. Twelve patients with T2DM who were scheduled to undergo laparoscopic RYGB surgery were separated into two groups, using a body mass index of 30 kg/m2 as a cut-off point. Venous blood was collected before operation and 12 months after operation. A significant change was observed in the peripheral blood miRNA expression profile of both groups after RYGB surgery compared with those before operation. The expression levels of hsa-miR-29a-3p, hsa-miR-122-5p, hsa-miR-124-3p, and hsa-miR-320a were downregulated. The methylation state of the CpG sites within an approximately 400-bp genomic DNA fragment of each of the four miRNA genes, including about 200 bp upstream and 100 bp downstream of the pre-miRNA, did not vary after RYGB surgery. With remission of T2DM in both groups, RYGB could modulate the expression level of many peripheral blood miRNAs associated with lipid metabolism, insulin secretion, beta-cell function, and insulin resistance. The expression level of peripheral blood diabetes-related miRNA varied in patients with T2DM after receiving RYGB surgery, laying a strong foundation for future studies on this subject. The molecular mechanisms underlying RYGB surgery that can cause aberrant expression of miRNA remains to be determined.
The iron chalcogenide Fe(1+y)(Te(1-x)Se(x)) is structurally the simplest of the Fe-based superconductors. Although the Fermi surface is similar to iron pnictides, the parent compound Fe(1+y)Te ...exhibits antiferromagnetic order with an in-plane magnetic wave vector (pi,0). This contrasts the pnictide parent compounds where the magnetic order has an in-plane magnetic wave vector (pi,pi) that connects hole and electron parts of the Fermi surface. Despite these differences, both the pnictide and chalcogenide Fe superconductors exhibit a superconducting spin resonance around (pi,pi). A central question in this burgeoning field is therefore how (pi,pi) superconductivity can emerge from a (pi,0) magnetic instability. Here, we report that the magnetic soft mode evolving from the (pi,0)-type magnetic long-range order is associated with weak charge carrier localization. Bulk superconductivity occurs as magnetic correlations at (pi,0) are suppressed and the mode at (pi, pi) becomes dominant for x>0.29. Our results suggest a common magnetic origin for superconductivity in iron chalcogenide and pnictide superconductors. PUBLICATION ABSTRACT
Iron chalcogenides are of particular interests among iron-based superconductors due to their distinct properties such as high-Tc on FeSe monolayer and competing magnetic correlations in Fe1+yTe. ...Here, in this work, we report unusual transport properties observed near the critical composition of Fe1+yTe (y ~ 0.09) where competing magnetic correlations exist. The resistivity exhibits surprising temperature-dependent relaxation behavior below TN, resulting in the increase of resistivity with time for 35 K < T < TN, but the decrease of resistivity with time for 10 K < T < 35 K. Such resistivity relaxation is intimately coupled to the magnetization relaxation and can be attributed to the glassy magnetic states induced by the competing magnetic orders. These findings demonstrate strong coupling between itinerant carriers and local ordered moments in Fe1+yTe.
Here, we report pair distribution function studies on the relationship between the metal–insulator transition (MIT) and lattice distortions in pure and Ti-substituted bilayer Ca3Ru2O7. Structural ...refinements performed as a function of temperature, magnetic field and length scale reveal the presence of lattice distortions not only within but also orthogonal to the bilayers. Because of the distortions, the local and average crystal structure differ across a broad temperature region extending from room temperature to temperatures below the MIT. The coexistence of distinct lattice distortions is likely to be behind the marked structural flexibility of Ca3Ru2O7 under external stimuli. This observation highlights the ubiquity of lattice distortions in an archetypal Mott system and calls for similar studies on other families of strongly correlated materials.
The laminar perovskite Ca3Ru2O7 naturally forms ferromagnetic double layers of alternating moment directions, as in the spin-valve superlattices. The mechanism of the huge magnetoresistive effect in ...the material has been controversial due to a lack of clear understanding of various magnetic phases and phase transitions. In this neutron diffraction study in a magnetic field, we identify four different magnetic phases in Ca3Ru2O7 and determine all first-order and second-order phase transitions between them. The spin-valve mechanism then readily explains the dominant magnetoresistive effect in Ca3Ru2O7.
The main processes underlying the generation and maintenance of biodiversity include both local factors such as competition and abiotic filtering and regional forces such as paleoclimate, speciation ...and dispersal. While the effects of regional and local drivers on species diversity are increasingly studied, their relative importance for other aspects of diversity, notably phylogenetic and functional diversity is so far little studied. Here, we link data from large Chinese forest plots to data on current and Last Glacial Maximum (LGM) climate as well as local disturbance regimes to study their relative roles in determining woody plant phylogenetic and functional diversity in this important hotspot for woody plant diversity. Local disturbance was the best predictor of functional diversity as represented by maximum canopy height (Hmax), probably reflecting the dominant role of competition for light in determining the forest Hmax structure. In contrast, the LGM–present anomaly in temperature was the factor with the strongest explanatory power for phylogenetic diversity, with modern climate also important. Hence, local contemporary and regional historical factors have highly contrasting importance for the geographic patterns of the functional (as represented by variation in maximum canopy height) and phylogenetic aspects of Chinese forest's woody plant diversity. Importantly, contemporary factors are of overriding importance for functional diversity, while paleoclimate has left a strong signature in the phylogenetic diversity patterns.
We presented and demonstrated a new type of vertical nanowire (NW) and nanosheet (NS) field-effect transistors (FETs), named vertical sandwich gate-all-around FETs or VSAFETs, which were formed with ...the process compatible in the main stream industry. The VSAFETs with self-aligned high-<inline-formula> <tex-math notation="LaTeX">{k} </tex-math></inline-formula> metal gates (HKMGs) were fabricated with epitaxy of Si/SiGe/Si sandwich structure, an isotropic quasi-atomic-layer-etch (qALE) process, and gate replacement process. The gate-length of VSAFETs is mainly determined by the thickness of SiGe film grown by epitaxy. The NW diameter and NS thickness could be obtained by the isotropic qALE method, which can be used to the Si-selective etching of SiGe. As a result, p-type NS and NW VSAFETs with good device characteristics were fabricated. Device performance and the influence of silicide, Ge fraction, Si cap, and high thermal process were investigated; threshold voltage tuning and reliability were also discussed.
We report the field-orientation dependent specific heat of the spin-triplet superconductor Sr2RuO4 under the magnetic field aligned parallel to the RuO2 planes with high accuracy. Below about 0.3 K, ...striking fourfold oscillations of the density of states reflecting the superconducting gap structure have been resolved for the first time. We also obtained strong evidence of multiband superconductivity and concluded that the superconducting gap in the active band, responsible for the superconducting instability, is modulated with a minimum along the 100 direction.
Spin-triplet superconductivity in Sr2RuO4 has attracted enormous interest. Like other unconventional superconductors, superconductivity in Sr2RuO4 is in close proximity to magnetic instability. ...Undoped Sr2RuO4 exhibits incommensurate antiferromagnetic (AFM) fluctuations, which can evolve into static, short-range AFM order via Ti doping. Moreover, weak ferromagnetic (FM) coupling in Sr2RuO4 has also been suggested by NMR/neutron scattering experiments and studies on Ca2-xSrxRuO4 and Sr2-yLayRuO4, implying orbital dependent magnetism. We report bulk static, short-range FM order in Sr2RuO4 triggered by <2% Co doping, showing superconductivity in Sr2RuO4 is much closer to FM instability than previously reported in Ca2-xSrxRuO4. We also find Mn doping can effectively establish incommensurate AFM order, with TN ~ 50 K for 3% Mn doping. These new results place Sr2RuO4 in a unique situation where superconductivity lies directly on the borderline of two distinct magnetic states, highlighting the important role of competing magnetic fluctuations in determining superconducting properties of Sr2RuO4.
One hundred forty-four 25-d-old weaning piglets with BW of 6.43 ± 0.39 kg were used in a 28-d trail to evaluate the effects of dietary addition of spray-dried chicken plasma (SDCP) as a replacement ...for spray-dried porcine plasma (SDPP) on growth performance, nutrient digestibility, diarrhea incidence, small intestinal morphology, digestive enzyme activity, and microflora. Pigs were randomly allotted to 1 of 4 dietary treatments: 1) CON (control; a basal diet), 2) SDPP (containing 5% SDPP), 3) SDPP + SDCP (containing 2.5% SDPP and 2.5% SDCP), and 4) SDCP (containing 5% SDCP). Six pigs from each treatment were randomly selected to collect serum and intestinal samples. Compared with the CON group, both the SDPP and the SDPP + SDCP groups improved final BW of pigs (P < 0.05), but there were no differences among the SDPP, SDPP + SDCP, and SDCP groups. From d 1 to 14 and d 15 to 28, pigs fed the SDPP and SDPP + SDCP diets had a greater (P < 0.05) ADG than pigs fed the CON diet. During the overall period, both ADG and ADFI of pigs in the SDPP and SDPP + SDCP groups were improved (P < 0.05) compared with pigs in the CON group. Furthermore, pigs fed diets containing SDPP or SDCP had a greater (P < 0.05) apparent total tract digestibility (ATTD) of CP, ether extract, Ca, and ash and less (P < 0.05) incidence of diarrhea than pigs fed the CON diet. However, no differences were observed for ATTD and diarrhea incidence between the SDPP and SDCP groups. Compared with the CON group, duodenal villus height and the ratio of villi to crypt were increased (P < 0.05) in the SDPP, SDPP + SDCP, and SDCP groups and jejunal crypt depth was decreased in the SDPP + SDCP and SDCP groups (P < 0.05). Pigs in the SDPP group had greater (P < 0.05) activities of amylase, maltase, and trypsin than pigs in the CON group. However, no significant differences were observed between the SDCP and SDPP groups. Additionally, inclusion of SDCP in diet decreased (P < 0.05) the population of Escherichia coli. In conclusion, these results demonstrated that the addition of SDCP in pigs’ diet had an effect similar to SDPP on improving growth performance through the promotion of the small intestinal development, increasing digestive enzymes activities, enhancing ATTD of nutrients, and decreasing diarrhea incidence.