This study examined the effect of high ambient temperature on the growth performance, meat quality, activity of the hypothalamo-pituitary-adrenal axis, and related gene expression in finishing pigs. All pigs received the same corn-soybean meal-based diet. Twenty-four Landrace pigs (initial bodyweight of 77.64 ± 0.67 kg) were assigned into three groups: Group 1 (22°C, ad libitum, 81% humidity); Group 2 (22°C, pair-fed to Group 3, 78% humidity); Group 3 (35°C, ad libitum, 78% humidity). The experiment lasted for 30 days. The average daily feed intake and average daily gain were markedly reduced in Group 3 compared with Group 1 (P < 0.05). The intramuscular fat content of longissimus dorsi muscle was decreased in Groups 2 and 3 (P < 0.05) when compared with Group 1. Muscle pH at 24 h post-mortem was higher in Group 3 (P < 0.05) compared with Groups 1 and 2, and the pH at 48 h post-mortem was higher in Group 3 (P < 0.05) than in Group 1. The MyHC IIb transcript abundance was lower in Group 3 (P < 0.05) than in the other two groups and that of MyHC IIx was higher in Group 3 than in Group 2 (P < 0.05). The relative abundance of calpastatin transcripts was lower in Group 3 (P < 0.05) than in the other two groups. Cortisol concentrations were lower in Group 3 (P < 0.05) than in Groups 1 and 2 on Day 3. Corticotropin releasing hormone concentrations in Group 3 were lower at Day 3 (P < 0.05) when compared with Group 2 and at Day 30 when compared with Groups 1 and 2. Glucagon concentrations were lower in Group 3 (P < 0.05) when compared with Groups 1 and 2 on Day 30. These results indicate that the decreased intramuscular fat content of pigs at high ambient temperature results from the reduction in feed intake. Independently of its effect on feed intake, high ambient temperature affected the meat quality of finishing pigs by increasing pH value probably due to the lower serum concentrations of corticotropin releasing hormone, and inducing a transition of muscle fibre types from IIb to IIx.

The corrosion and electrochemical behavior of aluminum in inhibited and uninhibited 4 M KOH-methanol-water mixed solutions with a methanol/water volume ratio of 3:2 were investigated by means of hydrogen collection, polarization curve, galvanostatic discharge, and electrochemical impedance spectroscopy (EIS). The results of hydrogen collection and electrochemical experiments showed that the addition of ZnO can obviously inhibit the corrosion of aluminum in the 4 M KOH-methanol-water solutions, and its inhibition effect can be enhanced in the hydroxytryptamine (HT)-containing KOH solution. The results of scanning electron microscopy (SEM) and energy dispersive analysis of X-ray (EDAX) revealed that ZnO produces the inhibition effect by the formation of a zinc-containing deposit layer on the surface of aluminum, and the cooperative effect of ZnO and HT may improve the deposit of zinc. The results of galvanostatic discharge indicated that aluminum can present good electrochemical activity in the 4 M KOH-methanol-water solution with 0.2 M ZnO and 1.0 mL/L HT.

A facile method based on electrospray mass spectrometry was established and validated for the differentiation of enantiomeric tadalafil isomers without using chiral chromatographic separation. The enantiomers were coupled with a chiral selector to form diastereomeric complex ions. Nickel-tadalafil complexes, [Ni (tadalafil)(l-Trp)-H] , produced a characteristic fragment ion at m/z 524 by loss of 1-methyl-1,6-dihydropyrazine-2,5-dione via collision-induced dissociation. The relative abundance of this fragment ion to the precursor contributed to differentiate tadalafil enantiomers, and energy-resolved product-ion spectra were applied to determine the molar composition of tadalafil in the mixture (R,R and S,S) as well. In addition, the other two forms of stereomeric isomers of tadalafil (R,S and S,R) could be also distinguished and analyzed by this method. The method was validated in different types of mass spectrometers (AB quadrupole time-of-flight and Bruker ion trap) and also verified by a chiral high-performance liquid chromatography coupled with quadrupole time-of-flight. The chiral determination of tadalafil using MS method proved to be rapid (1-min run time for each sample) and to have the same accuracy and precision comparable to chiral liquid chromatography mass spectrometry methods. This method provides an alternative to commonly used chromatographic technique for chiral determination and is particularly useful in rapid screening in enantioselective synthesis and enantiomeric impurity detection in pharmaceutical industry. Copyright © 2017 John Wiley & Sons, Ltd.

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Poly(ferrocenyldimethylsilanes) with different molecular weights, especially with high molecular weight, have been synthesized. It is found by using the ESR technique that the formation of charge transfer complexes (CTC) between poly(ferrocenyldimethylsilanes) with different molecular weights and tetracyanoethylene (TCNE) is possible. Using 2,2,6,6-Tetramethyl-piperidone-1 as a spin probe, the segment motion of resultant polymers was investigated.