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Objective: The objective of this study is to investigate the protein changes mechanism of buffalo meat during low temperature storage. Methods: Buffalo meat samples were stored at 4, -18 and -60 ℃, respectively, and the contents of total protein, surface hydrophobicity, total sulfhydryl, free sulfhydryl and carbonyl values were determined, following the analysis of the correlation among those protein indicators. Results: The results showed that the contents of total protein, total sulfhydryl and free sulfhydryl of buffalo meat decreased, with the extension of storage time, while the surface hydrophobicity and carbonyl value of buffalo meat increased. The protein oxidation increased showing linear relationship to the storage temperature. During cold or frozen storage, the total protein content was extremely significantly positively correlated with the contents of total sulfhydryl and free sulfhydryl (P＜0.01), while negatively correlated with surface hydrophobicity and carbonyl value (P＜0.01). The surface hydrophobicity was extremely significantly positively correlated with carbonyl value (P＜0.01), while negatively correlated with the contents of total protein, total sulfhydryl and free sulfhydryl (P＜0.01). Conclusion: The degree of protein oxidation of buffalo meat stored at -60 ℃ was the lowest, with the quality characteristics of buffalo meat maintained better, and its fresh-keeping effect was better than that of buffalo meat stored at 4 ℃ and -18 ℃.

BACKGROUND:The Bohai Sea contains a large amount of oil and gas, the main component of which is methane. The influence of natural or human factors will cause its leakage and migration and then have a negative impact on the environment. However, most of the methane would be oxidized by microorganisms during the leakage and migration processes. Meanwhile, the different environmental conditions will affect oxidation rate and carbon isotope fractionation of methane.OBJECTIVE:In order to better understand the law of isotope fractionation and methane oxidization in the sediments and to provide reference for further related research in this area, the Bohai Sea sediments were selected as laboratory raw materials for the degradation of laboratory experiments and are described in this paper.METHODS:Gas Chromatography and Gas Chromatography-Isotope Ratio Mass Spectrometry were used to determine the methane oxidation rate, and the carbon isotope fractionation coefficient ε of methane was determined.RESULTS:The results show that the aerobic oxidation of methane is dominant. Oxidation temperature and gas flow rate are the main factors affecting the rate of methane oxidation. In the mode of continuous incubation, when the temperature reduced from 28℃ to 15℃, the average oxidation rate reduced by 60%±10%, indicating that the lower temperature is not helpful for methane oxidation. When the gas flow rate increases from 50 to 150 μL/min, the average oxidation rate of methane increases by 90%±10%. This indicates that the higher gas flow rate is favorable to the increase of oxidation rate. It is also found that the fractionation effect of carbon and hydrogen isotopes are mainly affected by temperature where the fractionation degree is positively correlated with temperature.CONCLUSIONS:Temperature is an important factor affecting methane oxidation rate and isotopic fractionation.

We conducted a meta‐analysis to assess the effects of bundle‐care interventions on pressure ulcers in patients with stroke to provide a basis for clinical work. Randomised controlled trials on the effects of bundle‐care interventions in patients with stroke were identified using computerised searches of the PubMed, Embase, Cochrane Library, Chinese National Knowledge Infrastructure, VIP and Wanfang databases, from the time of inception of each database to July 2023, supplemented by manual literature searches. Two researchers independently retrieved and screened the articles, extracted the data and evaluated the quality of the included studies. After reaching consensus, meta‐analysis was performed using RevMan 5.4. Twenty‐four papers were included, involving 3330 patients of whom 1679 were in the intervention group and 1651 were in the control group. The results showed that, compared with standard care, bundle‐care interventions significantly reduced the incidence of pressure ulcers (3.28% vs. 14.84%, odds ratio [OR]: 0.19, 95% confidence interval [CI]: 0.14–0.26, p < 0.001), and aspiration (5.60% vs. 18.84%, OR: 0.25, 95% CI: 0.17–0.39, p < 0.001), and improved patient satisfaction with nursing care (96.59% vs. 84.43%, OR. 5.45, 95% CI: 3.76–7.90, p < 0.001). Current evidence suggests that care bundles are significantly better than conventional nursing measures in preventing pressure ulcers and aspiration, and improving patient satisfaction with nursing care in patients with stroke, and are worthy of clinical promotion and application. [ABSTRACT FROM AUTHOR]

The stable isotope of carbon and nitrogen (δ13C and δ15N) in marine sediments have received much attention as they can be used to trace the sources of organic matter and are helpful in understanding the carbon cycle, climate change and the transformation of organic matter in the ambient environment. However, during stable carbon and nitrogen isotopic analysis and testing, the standard reference materials for quality control are limited. Three reference materials of carbon and nitrogen stable isotope (MSCNI-1, MSCNI-2 and MSCNI-3) have been developed from marine sediments in the Bohai Jinzhou Bay, the coast of Fujian and Zhejiang in the east part of the China sea and the ocean through Okinawa within the East China Sea, respectively. All of these reference materials have certified values of the total carbon and nitrogen isotope (δ13C-TC, δ15N-TN) and organic carbon and nitrogen isotope (δ13C-Corg, δ15N-Norg) which were determined by an inter-laboratory comparison of 8 participating laboratories, using Element Analysis-Isotope Ratio Mass Spectrometry (EA-IRMS). The analytical results indicate that three reference materials were homogeneous (in Table 1) and stable (in Table 2) as the certified values had no statistically variations within a year. The standard uncertainties of δ13C and δ15N were less than 0.15% and 0.24% (in Table 4), respectively. Both of the certified values and uncertainties are within acceptable limits. The reference materials of natural carbon and oxygen isotopes were initially developed based on marine sediments in China. The test method was accurate and reliable, thus it is anticipated that it can be used for instrument calibration, method evaluation and quality control in related laboratories such as marine, geological and environmental fields.

In the study of the regulation of incubation, broodiness and laying performance in pigeons (Columba liva), a cDNA library, which was enriched with full-length brooding-related genes, was constructed by SMART LD-PCR techniques using the pituitary glands of incubating White King pigeons. The titers of optimal primary libraries were 1.54×106 pfu/mL and 1.80×106 pfu/mL and the titers of amplified libraries were 1.89×108 pfu/mL and 2.32×109 pfu/mL. The percentages of recombinant clones of primary libraries and amplified libraries were all over 90%. A positive clone was sequenced and named ubiquitin based on the highly similar from other species. The fragment has the four initial codons of ATG, a termination codon of TAA and a signal sequence of AATAAA for adding the poly-A tail. The open reading frame of 918bp encodes 305 amino acids (NCBI accession number is EU981283). Recombinant pigeon ubiquitin protein was efficiently expressed with the form of insoluble inclusion bodies in E. coli BL21 transformed with a pET28a+ expression vector containing the DNA sequence encoding mature pigeon ubiquitin. The molecular weight of expressed protein is the same as predicted size of approximately 35kD. To improve the efficiency of cloning full-length cDNA, strategies of RACE combined with cDNA library were used. The length of pigeons ubiquitin-conjugating enzyme gene obtained was 1263 bp containing a complete open reading frame of 435 bp that encodes 144 aa (NCBI accession number is EU914824). The results of this study not only provide a starting point for further study of ubiquitin function in pigeon species, but also provide a starting point for investigating the brooding mechanisms of pigeons.

Synthesis and complete characterization of four new luminescent organoboron complexes are achieved by changing the substituent group on the 8-hydroxyquinolato ligand. An introductory review of the electroluminescent constituents of B(2-benzothienyl)(sub 2q) is also presented.