Synthesis and evaluation of a novel chiral derivatization reagent for resolution of carboxylic acid enantiomers by RP-HPLC

Li, L.P.,Jin, M.N.,Shi, Q.,Xu, C.Y.,Jiang, Y.Z.,Lee, Y.I.,Min, J.Z. Academic Press 2017 Microchemical Journal Vol. No.

<P>A novel derivatization reagent, N-[1-Oxo-5-(triphenylphosphonium)pentyl]-(S)-3-aminopyrrolidine (OTPA), with triphenylphosphine (TPP) as a basic structure carrying a permanent positive charge was developed for the enantiomeric separation of chiral carboxylic acids by high-performance liquid chromatography (HPLC). OTPA reacted with the carboxylic acids at 40 degrees C within 90 min in the presence of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and 1-hydroxybenzotriazole (HOBt). The degree of epimerization (racemization) during the derivatization reaction was negligible. The separability of the diastereomers was evaluated in terms of their resolution value (Rs). The Rs values of the derivatives of non-steroidal anti-inflammatory drugs (NSAIDs), which were selected as the representative carboxylic acids, were completely separated by reversed-phase chromatography using an ODS (4.6 mm x 150 mm I.D., 5.0 mu m) column. The resolution Rs values were 1.54-2.23 for the evaluated carboxylic acids and the OTPA-derivatization was also effective for the enantiomeric separation of chiral carboxylic acids. The calibration curves (r(2) > 0.9971) were linear over the concentration range of 0.0125-1.25 mM for each enantiomer of ketoprofen (KET), and naproxen (NAP), 0.05-1.0 mM for each enantiomer of ibuprofen (IBU), 2-phenylpropionic acid (PPA), and loxoprofen (LOX), and 0.05-1.25 mM for each enantiomer of PBA. The limit of detection (S/N = 3) for each of the enantiomers of the NSAIDs and chiral carboxylic acid enantiomers was 1.4-7.6 mu mol/L. The inter-day and intra-day assay precisions were all <6.77% and the mean recoveries (%) of the NSAIDs and chiral carboxylic acids from the spiked human plasma were 95.27-101.12%. The derivatization followed by HPLC-UV enabled the separation and detection of NAP in human plasma with simple pretreatment. (C) 2017 Elsevier B.V. All rights reserved.</P>

Effects of Water-misting Sprays with Forced Ventilation after Transport during Summer on Meat Quality, Stress Parameters, Glycolytic Potential and Microstructures of Muscle in Broilers

Jiang, N.N.,Xing, T.,Wang, P.,Xie, C.,Xu, X.L. Asian Australasian Association of Animal Productio 2015 Animal Bioscience Vol.28 No.12

Effects of water-misting sprays with forced ventilation after transport during summer on meat quality, stress parameters, glycolytic potential and microstructures of muscle in broilers were investigated. A total of 105 mixed-sex Arbor Acres broilers were divided into three treatment groups: i) 45-min transport without rest (T group), ii) 45-min transport with 1-h rest (TR group), iii) 45-min transport with 15-min water-misting sprays with forced ventilation and 45-min rest (TWFR group). The results showed the TWFR group significantly increased (p<0.05) initial muscle pH ($pH_i$) and ultimate pH ($pH_u$) and significantly reduced $L^*$ (p<0.05), drip loss, cook loss, creatine kinase, lactate dehydrogenase activity, plasma glucose content, lactate and glycolytic potential when compared with other groups. Microstructure of the muscle from TWFR group broilers under light microscopy showed smaller intercellular spaces among muscle fibers and bundles compared with T group. In conclusion this study indicated water-misting sprays with forced ventilation after transport could relieve the stress caused by transport under high temperature, which was favorable for the broilers' welfare. Furthermore, water-misting sprays with forced ventilation after transport slowed down the postmortem glycolysis rate and inhibited the occurrence of PSE-like meat in broilers. Although rest after transport could also improve the meat quality, the effect was not as significant as water-misting sprays with forced ventilation after transport.

Continuous cocycle superrigidity for shifts and groups with one end

Chung, N. P.,Jiang, Y. J. Springer [etc.] 2017 Mathematische Annalen Vol. No.

<P>We prove that if a finitely generated group G is not torsion then a necessary and sufficient condition for every full shift over G has (continuous) cocycle superrigidity is that G has one end. It is a topological version of the well-known Popa's measurable cocycle superrigidity theorem (Cocycle and orbit equivalence superrigidity for malleable actions of w-rigid groups. Invent. Math. 170(2): 243-295, 2007). For the proof of sufficiency, we introduce a new specification property for shifts over general groups which plays a similar role as malleable property in the measurable setting. This new specification property is good enough for us to extend the method of using homoclinic equivalence relation that was introduced by Schmidt (Pac J Math 170(1): 237-269, 1995) to study cocycle rigidity for Z(d) -shifts. Indeed, in this direction we prove this superrigidity result for certain more general systems. And for the necessary condition, we apply Specker's characterization for ends of groups via the associated first cohomology groups to get the result. Finally, combining our results with Li (Ergod Theory Dyn Syst. arXiv: 1503.01704, Theorem 1.6), we have an application in continuous orbit equivalence rigidity.</P>

Empirical Selection of Informative Microsatellite Markers within Co-ancestry Pig Populations Is Required for Improving the Individual Assignment Efficiency

Lia, Y.H.,Chu, H.P.,Jiang, Y.N.,Lin, C.Y.,Li, S.H.,Li, K.T.,Weng, G.J.,Cheng, C.C.,Lu, D.J.,Ju, Y.T. Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.5

The Lanyu is a miniature pig breed indigenous to Lanyu Island, Taiwan. It is distantly related to Asian and European pig breeds. It has been inbred to generate two breeds and crossed with Landrace and Duroc to produce two hybrids for laboratory use. Selecting sets of informative genetic markers to track the genetic qualities of laboratory animals and stud stock is an important function of genetic databases. For more than two decades, Lanyu derived breeds of common ancestry and crossbreeds have been used to examine the effectiveness of genetic marker selection and optimal approaches for individual assignment. In this paper, these pigs and the following breeds: Berkshire, Duroc, Landrace and Yorkshire, Meishan and Taoyuan, TLRI Black Pig No. 1, and Kaohsiung Animal Propagation Station Black pig are studied to build a genetic reference database. Nineteen microsatellite markers (loci) provide information on genetic variation and differentiation among studied breeds. High differentiation index ($F_{ST}$) and Cavalli-Sforza chord distances give genetic differentiation among breeds, including Lanyu's inbred populations. Inbreeding values ($F_{IS}$) show that Lanyu and its derived inbred breeds have significant loss of heterozygosity. Individual assignment testing of 352 animals was done with different numbers of microsatellite markers in this study. The testing assigned 99% of the animals successfully into their correct reference populations based on 9 to 14 markers ranking D-scores, allelic number, expected heterozygosity ($H_E$) or $F_{ST}$, respectively. All miss-assigned individuals came from close lineage Lanyu breeds. To improve individual assignment among close lineage breeds, microsatellite markers selected from Lanyu populations with high polymorphic, heterozygosity, $F_{ST}$ and D-scores were used. Only 6 to 8 markers ranking $H_E$, $F_{ST}$ or allelic number were required to obtain 99% assignment accuracy. This result suggests empirical examination of assignment-error rates is required if discernible levels of co-ancestry exist. In the reference group, optimum assignment accuracy was achievable achieved through a combination of different markers by ranking the heterozygosity, $F_{ST}$ and allelic number of close lineage populations.

A nonlinear model of flow-structure interaction between steam leakage through labyrinth seal and the whirling rotor

W. Z. Wang,Y. Z. Liu,G. Meng,P. N. Jiang 대한기계학회 2009 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.23 No.12

A nonlinear model of flow-structure interaction between steam leakage through labyrinth seal and the whirling rotor was presented. The particular concern was placed on incorporating thermal properties of the steam fluid into the mathematical model. To see the influence of the steam fluid on the whirling rotor, two sets of thermal parameters of the steam fluid, e.g., temperature and pressure drop in each seal cavity, were selected from the typical 1000 MW supercritical and 300 MW subcritical power units in China. The interlocking seal widely employed in practical situations was chosen for study. The rotor-seal system was modeled as a Jeffcott rotor subject to shear stress and pressure force associated with the steam leakage. Spatio-temporal variation of the steam forcing on the rotor surface in the coverage of the seal clearance and the cavity volume was specifically delineated by using the Muzynska model and the perturbation analysis, respectively. The governing equation of rotor dynamics including the influence of the steam leakage was solved by using the fourth-order Runge-Kutta method, resulting in the orbit of the whirling rotor. Stability of the rotor was inspected by using Liapunov’s first method. The results showed that the destabilization speed of the rotor was significantly influenced by the steam leakage.