Whole-genome resequencing reveals the uniqueness of Subei yak.

Subei yak is an essential local yak in the Gansu Province, which genetic resource has recently been discovered. It is a meat-milk dual-purpose variety with high fecundity and relatively stable population genetic structure. However, its population genetic structure and genetic diversity are yet to be reported. Therefore, this study aimed to identify molecular markers of Subei yak genome by whole-genome resequencing, and to analyze the population structure and genetic diversity of Subei yak. This study screened 12,079,496 single nucleotide polymorphism (SNP) molecular markers in the 20 Subei yaks genome using whole-genome resequencing technology. Of these SNPs, 32.09% were located in the intronic region of the genome. Principal component analysis, phylogenetic analysis, and population structure analysis revealed that the Subei yak belonged to an independent group in the domestic yak population. A selective clearance analysis was carried out on Subei yak and other domestic yaks, and the genes under positive selection were annotated. The functional enrichment analysis showed that Subei yak possessed prominent selection characteristics in terms of external environment perception, hypoxia adaptation, and muscle development. Furthermore, Subei yak showed excellent muscle fat deposition and meat quality traits. Thus, this study will serve as a reference for discovering population structure, genetic evolution, and other unique traits of Subei yak and for expanding the genetic variation catalog of yaks.

Subei yak is an important local yak genetic resource newly discovered in Gansu Province. In this study, the molecular markers of Subei yak genome were identified by whole-genome resequencing. Principal component analysis, phylogenetic analysis, and population structure analysis showed that Subei yak belonged to an independent group in the domestic yak population. In addition, functional enrichment analysis showed that Subei yaks had prominent selection characteristics in external environment perception, hypoxia adaptation, and muscle development.

Procaine stimulates aquaporin­5 expression in human salivary gland ductal cells via the suppression of DNA methyltransferase­1.

The present study aimed to investigate whether procaine may upregulate the expression of aquaporin­5 (AQP5) in human salivary gland ductal cells and the underlying mechanisms of this upregulation. Immortalized normal human salivary gland ductal cells (NS­SV­DC), lacking AQP5 protein expression, were used to measure the glandular secretion rate following treatment with procaine, and the protein expression levels of AQP5 in NS­SV­DC cells were measured by western blotting. In order to investigate the mechanism of procaine action on AQP5 protein expression, the protein expression and activity of DNA methyltransferase (DNMT)1, and the CpG methylation of AQP5, were investigated further. In NS­SV­DC cells treated with procaine, the mRNA and protein levels of AQP5, and the secretion rate of cells, were significantly increased. Although no significant alterations were observed in the protein expression of DNMT1 following procaine treatment, its enzymatic activity was reduced, resulting in CpG island demethylation at Sp1­2 and Sp1­3 sites of the AQP5 gene, which may contribute to the significantly upregulated AQP5 gene expression. The results of the present study indicate that procaine may upregulate the protein expression of AQP5 in human submandibular glands by inhibiting the activity of DNMT1 and promoting liquid secretion. The procaine­mediated expression of AQP5 may provide a novel regimen for the treatment of SS syndrome.

Combined effect of constant high voltage electrostatic field and variable frequency pulsed electromagnetic field on the morphology of calcium carbonate scale in circulating cooling water systems.

Research on scale inhibition is of importance to improve the heat transfer efficiency of heat exchangers. The combined effect of high voltage electrostatic and variable frequency pulsed electromagnetic fields on calcium carbonate precipitation was investigated, both theoretically and experimentally. Using energy dispersive spectrum analysis, the predominant phase was found to be CaCO(3). The formed crystal phases mainly consist of calcite and aragonite, which is, in part, verified by theory. The results indicate that the setting of water flow velocity, and high voltage electrostatic and variable frequency pulsed electromagnetic fields is very important. Favorable values of these parameters can have a significant anti-scaling effect, with 68.95% of anti-scaling ratio for scale sample 13, while unfavorable values do not affect scale inhibition, but rather promoted fouling, such as scale sample 6. By using scanning electron microscopy analysis, when the anti-scaling ratio is positive, the particle size of scale was found to become smaller than that of untreated sample and the morphology became loose. The X-ray diffraction results verify that the good combined effect favors the appearance and growth of aragonite and restrains its transition to calcite. The mechanism for scale reduction is discussed.

Structural stability and phase transition in OsC and RuC.

The structural stability and phase transition of osmium and ruthenium carbides (OsC and RuC) were investigated by first principles. Nine structures were considered for each carbide. Zinc blende structure has the lowest energy among the considered structures at ambient conditions for both carbides. For OsC at elevated pressures, the most stable phase is zinc blende structure from 0 to 10 GPa, FeSi from 10 to 32 GPa. In these two structures, Os atom is fourfold coordinated. From 32 to 40 GPa, tungsten carbide (WC) and NiAs are energetically competitive with Os atom sixfold coordinated. NiAs becomes energetically the most stable structure above 40 GPa. For RuC, zinc blende structure is the most stable from 0 to 20 GPa. From 20 to 100 GPa, WC structure is the most stable.

Phase stability and mechanical properties of tungsten borides from first principles calculations.

The phase stability and mechanical properties of tungsten borides W(2)B, WB, WB(2), W(2)B(5) and WB(4) were extensively studied by first-principles calculations within density functional theory. The thermodynamic and mechanical stabilities were examined. Our calculations on the enthalpy-pressure relationship and convex hulls have demonstrated that at zero pressure, the experimentally observed W(2)B-W(2)B (W(2)B-W(2)B represents W(2)B in W(2)B structure type, the same hereinafter) and WB-WB, and assumed WB(2)-ReB(2) phases are stable against decomposition into other components. The estimated hardness of WB(2)-ReB(2) is 39.4 GPa, suggesting that it is a potentially hard compound. At 60 GPa, the most stable phases are WB-WB and WB(2)-WB(2). WB-WB, WB(2)-AlB(2) and WB(4) are the ground state phases at 100 GPa. The phase transition mechanism for WB(2) was discussed. The synthesis of WB(2)-AlB(2) could be conducted at high pressures.

Phase stability and mechanical properties of rhenium borides by first-principles calculations.

The phase stability and elastic properties of Re-B system were systematically investigated by use of the density functional theory. The formation enthalpies are negative for Re(3)B, Re(7)B(3), Re(2)B, ReB, Re(2)B(3), and ReB(2), indicating that they are thermodynamically stable. Re(7)B(3), Re(2)B, ReB, Re(2)B(3), and ReB(2) are mechanically stable. Combining the study of enthalpy and pressure relationship with the convex hull, it was found that the ground state phases are Re(3)B, Re(7)B(3), and ReB(2) at zero pressure, in agreement with the experimental observations. At the pressure of 90 GPa, Re(3)B, and ReB(2) are the most stable phases.

First principles investigation on the ultra-incompressible and hard TaN.

The structural, electronic, and mechanical properties of TaN were investigated by use of the density functional theory (DFT). Eight structures were considered, i.e., hexagonal WC, TaN, NiAs, wurtzite, and CoSn structures, cubic NaCl, zinc-blende and CsCl structures. The results indicate that TaN in TaN-type structure is the most stable at ambient conditions among the considered structures. Above 5 GPa, TaN in WC-type structure becomes energetically the most stable phase. They are also stable both thermodynamically and mechanically. TaN in WC-type has the largest shear modulus 243 GPa and large bulk modulus 337 GPa among the considered structures. The volume compressibility is slightly larger than diamond, but smaller than c-BN at pressures from 0 to 100 GPa. The compressibility along the c axis is smaller than the linear compressibility of both diamond and c-BN. The estimated hardness is 34 GPa. Thus, TaN in WC-type structure is a potential candidate to be ultra-incompressible and hard. The unique mechanical properties of TaN in WC-type structure would make it suitable for applications under extreme conditions.

Near compensated half-metal in Sr2NiOsO6.

The electronic and magnetic properties of tetragonal double perovskite Sr(2)NiOsO(6) were studied by use of the density functional theory and including the spin-orbit coupling. Compensated half-metal is found if the spin-orbit coupling is not considered. Spin-orbit coupling induces orbital moments on both Ni and Os, making Sr(2)NiOsO(6) a near compensated half-metal. Ferromagnetic phase is slightly favored over antiferromagnetic phase (by 4 meV). The small energy difference also suggests that both phases are competitive for the ground state. At ferromagnetic phase, the calculated net magnetic moment is 3.53 micro(B), in good agreement with experimental value of 3.44 micro(B). At antiferromagnetic phase, the net magnetic moment is 0.69 micro(B), in which the contribution from the net spin moment is 0.09 micro(B).

[Relationship between condylar marrow signal abnormalities and temporomandibular joint internal derangement].

OBJECTIVE: To investigate the relationship between condylar marrow signal abnormalities and temporomandibular joint internal derangement (TMJID). METHODS: Oblique sagittal T1 weighted MR imaging at closed and open mouth and Oblique sagittal T2 weighted MR imaging at closed mouth were obtained from 88 joints of 44 patients suffering from TMD. Condylar marrow signal abnormalities were reviewed and classified into bone marrow edema pattern (hypointense T1, hyperintense T2), sclerosis pattern (hypointense T1 and hypointense T2) and combined edema and sclerosis pattern. RESULTS: Of 88 joints, 13 (14.8%) joints showed condylar marrow signal abnomalities, among which 11 belonged to edema pattern and, 1 was sclerosis pattern and the other was the combined patten. Of 13 joints with condylar marrow signal abnomalities, 11 (84.6%) had TMJID. Of 75 joints with normal marrow signal, 25 (33.3%) joints had TMJID. There was significant correlation between condylar marrow signal abnormalities and TMJID (P < 0.05). CONCLUSION: Disc displacement is one of the factors inducing condylar marrow signal abnormalities. The pathological process from disc displacement to osteonecrosis requires further study.

[Relationship between condylar marrow signal abnormalities and temporomandibular joint pain].

PURPOSE: To investigate the relationship between condylar marrow signal abnormalities and joint pain. METHODS: Oblique sagittal T1 and T2 weighted MR imaging at closed mouth was obtained from 88 joints of 44 patients who complained of unilateral TMJ pain. The condylar marrow signal of pain-free side served as self-control. All patients rated their pain levels by a visual analogue scale (VAS). RESULTS: Of 44 painful joints, 11(25% joints showed condylar marrow signal abnormalities, all of which were edema pattern. While there had condylar marrow signal abnormalities only in 2 (4.5%) of 44 pain-free TMJs. There was significant correlation between joint pain and condylar marrow signal abnormalities (P<0.01). The VAS score of patients with and without condylar marrow signal abnormalities was respectively 39.5+/-27.5 and 42.6+/-21.9, There was no correlation between them (P=0.696). CONCLUSION: Temporomandibular joint pain is closely correlated with condylar marrow signal abnormalities, but the pain degree has no association with it.