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The objective of this study was to probe into the polymorphism of Y-STR INRA189 and identify the geographical distribution pattern of its alleles in the Chinese domestic yak gene pool. We examined the variation at INRA189 locus in 682 male yaks representing 15 breeds/populations in China. The results showed that six alleles, including five reported previously (149, 155, 157, 159, and 161 bp) and a new one identified in this study (139 bp), were detected at INRA189 locus based on genotyping analysis. The frequencies of six alleles varied among the 15 yak breeds/populations with a clear phylogeographical pattern, which revealed the paternal genetic difference among Chinese yak breeds/populations. The average polymorphism information content (PIC) among the 15 yak breeds/populations was 0.32, indicating INRA189 to be an intermediate polymorphic Y-STR marker (0.25 < PIC < 0.5) in yak. Sequence alignment revealed that the variations among six alleles at INRA189 were defined by a TG dinucleotide repeat motif, which repeated for 12, 17, 20, 21, 22, and 23 times, corresponding to the alleles of 139, 149, 155, 157, 159, and 161 bp, respectively. Therefore, we believe that the polymorphic yak Y-STR INRA189 can be used to characterize male-mediated genetic events, including paternal genetic origin, diversity, and evolution.

BackgroundWith the development of thorium molten salt reactor nuclear energy system (TMSR) from experimental reactor to research, demonstration and commercial reactor, its shafting evolved into the slender flexible rotor supported by submerged bearing. High temperature molten-salt pump is the main power device of TMSR, its stability and reliability are critical to the submerged bearing support characteristics.PurposeThis study aims to analyze bearing eccentricity on support characteristics of high temperature molten-salt pump for TMSR.MethodsThe numerical simulation method in Beperf module of DyRoBeS software was used for the theoretical calculation and analysis of the submerged bearing. Combined with experimental verification, the influences of various eccentricity on the supporting characteristics of the bearing were studied.ResultsThe results show that the eccentricity of the bearing decreases with the increase of rotational speed. With the augmentation of eccentricity, the orthogonal stiffness and damping of the bearing is increasing continuously, so are the cross stiffness and damping. Conversely, the thickness of minimum liquid film reduces continuously. The bearing pressure ends up with zero and zero gradient due to the attenuation of the minimum liquid film thickness when the eccentricity is greater than 0.6.ConclusionsIt is verified that the liquid membrane invalidation brings about serious wear of the bearing in actual operation, and this study provides theoretical guidance and experimental data support for the design of the submerged bearings of ultra-high temperature long shaft molten-salt pump.

Ziziphi Spinosae Semen refers to the dried seed of Ziziphus jujuba Mill. var. spinosa (Bunge) Hu ex H. F. Chou. The seed is composed of a reddish brown coat and a yellow kernel. A comparative study was conducted to investigate differences in the chemical composition and their relative contents between the seed coat and kernel of Ziziphi Spinosae Semen. First, the chemical compounds found in the seed coat and kernel were characterized and identified using ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS). The analytical results tentatively identified 57 chemical compounds based on reference-compound comparison, literature retrieval, and chemical-database (e. g., MassBank) searches; these compounds included 14 triterpenes, 23 flavonoids, 7 alkaloids, 6 carboxylic acids, and 7 other types of compounds. The mass error of the identified compounds was within the mass deviation range of 5×10 -6 (5 ppm). Next, two methods of multivariate statistical analysis, namely, principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA), were used to compare the differential compounds between the two seed parts. A total of 17 differential compounds were screened out via OPLS-DA based on a variable importance in projection (VIP) value of >5. The results revealed that betulinic acid, betulonic acid, alphitolic acid, and jujuboside Ⅰ mainly existed in the seed coat whereas the 13 other compounds, such as spinosin, jujuboside A, and 6‴-feruloylspinosin, mainly existed in the seed kernel. Therefore, these 17 differential compounds can be used to distinguish between the two seed parts. Finally, a semiquantitative method was established using UPLC and a charged aerosol detector (CAD) with inverse gradient compensation in the mobile phase. Six representative compounds with different types were selected to examine the CAD response consistency: magnoflorine (alkaloid), spinosin (flavone), 6‴-feruloylspinosin (flavone), jujuboside A (triterpenoid saponin), jujuboside B (triterpenoid saponin), and betulinic acid (triterpenoid acid). The results showed that the relative standard deviation (RSD) of the average response factors at different levels of these six compounds was 7.04% and that their response intensities were similar. Moreover, each compound in the fingerprint demonstrated good response consistency, and the peak areas obtained directly reflected the contents of each compound. Based on the semiquantitative fingerprints obtained, betulinic acid and oleic acid were considered the main components of the seed coat. The betulinic acid content in the seed coat was approximately 7 times higher than that in the seed kernel. Spinosin, jujuboside A, linoleic acid, betulinic acid, and oleic acid were the main components of the seed kernel. The spinosin content in the seed kernel was 18 times higher than that in the seed coat. In addition, the jujuboside A content in the seed kernel was 24 times higher than that in the seed coat. The proposed method can accurately determine the main components and compare the relative contents of these components in different seed parts. In summary, this study identified the differences in chemical components between the seed coat and kernel of Ziziphi Spinosae Semen and clarified the main components and their relative contents in these parts. The findings can not only provide a basis for the identification of chemical compounds and quality research on different parts of Ziziphi Spinosae Semen but also promote the development and utilization of this traditional Chinese medicine.

Aim: To compare the wavefront aberrations and corneal surface regularity between dry eye (DE) patients and normal subjects and assess its diagnostic performance for DE measured with OPD Scan-III., Methods: Fifty right eyes of 50 DE patients and 31 right eyes of normal subjects were included. The examinations for ocular surface including logarithm of the minimum angle of resolution best-corrected distance visual acuity (logMAR BCVA) the ocular surface disease index (OSDI), tear film break-up time (TBUT) and corneal fluorescein staining (CFS). OPD Scan-III was used to measure anterior corneal aberrations including total corneal aberrations, high order aberration (HOA), coma, trefoil, spherical aberration (SA), standard deviation of corneal power (SDP), surface regularity index (SRI) and surface asymmetry index (SAI). Statistical analysis were assessed with nonparametric tests and Spearman's correlations. All parameters were also analyzed for sensitivity, specificity, and receiver operating characteristics (ROC) curves., Results: Wavefront aberrations parameters including total corneal aberrations, HOA, coma, trefoil, and SA in DE group were significantly higher than those in normal group ( P <0.001). Corneal surface regularity parameters including SRI and SAI in DE group were significantly higher than both in normal group ( P <0.05). All the wavefront aberrations parameters had significant correlations with ocular surface parameters ( P <0.05). The logMAR BCVA had positive correlations with SAI and SRI (all P <0.001). CFS scores had positive correlations with SAI and SRI (all P <0.001). All the wavefront aberrations parameters showed good diagnosis sensitivity and specificity, however, the corneal regularity parameters showed only good specificity but poor sensitivity. The cut-off value selected for trefoil in diagnosis DE showed the highest area under the curve (AUC, 0.921) values as compared to the other parameters with sensitivity of 0.955 and specificity of 0.867., Conclusion: Wavefront aberrations and corneal surface regularity are increased in DE patients and also correlated with ocular surface parameters. Wavefront aberrations parameters have potential to be indicators to diagnosis and monitor DE., (International Journal of Ophthalmology Press.)