The deposition and hydrolysis reaction of SO2 + H2O in small clusters of sulfuric acid and water are studied by theoretical calculations of the molecular clusters SO2-(H2SO4)n-(H2O)m (m = 1,2; n = 1,2). Sulfuric acid exhibits a dramatic catalytic effect on the hydrolysis reaction of SO2 as it lowers the energy barrier by over 20 kcal/mol. The reaction with monohydrated sulfuric acid (SO2 + H2O + H2SO4 - H2O) has the lowest energy barrier of 3.83 kcal/mol, in which the cluster H2SO4-(H2O)2 forms initially at the entrance channel. The energy barriers for the three hydrolysis reactions are in the order SO2 + (H2SO4)-H2O > SO2 + (H2SO4)2-H2O > SO2 + H2SO4-H2O. Furthermore, sulfurous acid is more strongly bonded to the hydrated sulfuric acid (or dimer) clusters than the corresponding reactant (monohydrated SO2). Consequently, sulfuric acid promotes the hydrolysis of SO2 both kinetically and thermodynamically. Kinetics simulations have been performed to study the importance of these reactions in the reduction of atmospheric SO2. The results will give a new insight on how the pre-existing aerosols catalyze the hydrolysis of SO2, leading to the formation and growth of new particles.

The study of high-performance electrocatalysts for driving the oxygen evolution reaction (OER) is important for energy storage and conversion systems. As a representative of inverse-spinel-structured oxide catalysts, nickel ferrite (NiFe 2 O 4 ) has recently gained interest because of its earth abundance and environmental friendliness. However, the gained electrocatalytic performance of NiFe 2 O 4 for the OER is still far from the state-of-the-art requirements because of its poor reactivity and finite number of surface active sites. Here, we prepared a series of atomically thin NiFe 2 O 4 catalysts with different lateral sizes through a mild and controllable method. We found that the atomically thin NiFe 2 O 4 quantum dots (AT NiFe 2 O 4 QDs) show the highest OER performance with a current density of 10 mA cm −2 at a low overpotential of 262 mV and a small Tafel slope of 37 mV decade −1 . The outstanding OER performance of AT NiFe 2 O 4 QDs is even comparable to that of commercial RuO 2 catalyst, which can be attributed to its high reactivity and the high fraction of active edge sites resulting from the synergetic effect between the atomically thin thickness and the small lateral size of the atomically thin quantum dot (AT QD) structural motif. The experimental results reveal a negative correlation between lateral size and OER performance in alkaline media. Specifically speaking, the number of low-coordinated oxygen atoms increases with decreasing lateral size, and this leads to significantly more oxygen vacancies that can lower the adsorption energy of H 2 O, increasing the catalytic OER efficiency of AT NiFe 2 O 4 QDs.

Tibetan pigs that inhabit the Tibetan Plateau exhibit striking phenotypic and physiological differences from lowland pigs, and have adapted well to extreme conditions. However, the mechanisms involved in regulating gene expression at high altitude in these animals are not fully understood. In this study, we obtained transcriptomic and proteomic data from the heart tissues of Tibetan and Yorkshire pigs raised in the highlands (TH and YH) and lowlands (TL and YL) via RNA-seq and iTRAQ (isobaric tags for relative and absolute quantitation) analyses, respectively. Comparative analyses of TH vs. YH, TH vs.TL, TL vs. YL, and YH vs. YL yielded 299, 169, 242, and 368 differentially expressed genes (DEGs), and 473, 297, 394, and 297 differentially expressed proteins (DEPs), respectively. By functional annotation of these DEGs and DEPs, genes that were enriched in the HIF-1 signaling pathway (NPPA, ERK2, ENO3, and EGLN3), VEGF signaling pathway (ERK2, A2M, FGF1, CTGF, and DPP4), and hypoxia-related processes (CRYAB, EGLN3, TGFB2, DPP4, and ACE) were identified as important candidate genes for high-altitude adaptation in the Tibetan pig. This study enhances our understanding of the molecular mechanisms involved in hypoxic adaptation in pigs, and furthers our understanding of human hypoxic diseases.

Transcriptome profiles established using high-throughput sequencing can be effectively used for screening genome-wide differentially expressed genes (DEGs). RNA sequences (from RNA-seq) and microRNA sequences (from miRNA-seq) from the tissues of longissimus dorsi muscle of two indigenous Chinese pig breeds (Diannan Small-ear pig [DSP] and Tibetan pig [TP]) and two introduced pig breeds (Landrace [LL] and Yorkshire [YY]) were examined using HiSeq 2000 to identify and compare the differential expression of functional genes related to muscle growth and lipid deposition. We obtained 27.18 G clean data through the RNA-seq and detected that 18,208 genes were positively expressed and 14,633 of them were co-expressed in the muscle tissues of the four samples. In all, 315 DEGs were found between the Chinese pig group and the introduced pig group, 240 of which were enriched with functional annotations from the David database and significantly enriched in 27 Gene Ontology (GO) terms that were mainly associated with muscle fiber contraction, cadmium ion binding, response to organic substance and contractile fiber part. Based on functional annotation, we identified 85 DEGs related to growth traits that were mainly involved in muscle tissue development, muscle system process, regulation of cell development, and growth factor binding, and 27 DEGs related to lipid deposition that were mainly involved in lipid metabolic process and fatty acid biosynthetic process. With miRNA-seq, we obtained 23.78 M reads and 320 positively expressed miRNAs from muscle tissues, including 271 known pig miRNAs and 49 novel miRNAs. In those 271 known miRNAs, 20 were higher and 10 lower expressed in DSP-TP than in LL-YY. The target genes of the 30 miRNAs were mainly participated in MAPK, GnRH, insulin and Calcium signaling pathway and others involved cell development, growth and proliferation, etc. Combining the DEGs and the differentially expressed (DE) miRNAs, we drafted a network of 46 genes and 18 miRNAs for regulating muscle growth and a network of 15 genes and 16 miRNAs for regulating lipid deposition. We identified that CAV2, MYOZ2, FRZB, miR-29b, miR-122, miR-145-5p and miR-let-7c, etc, were key genes or miRNAs regulating muscle growth, and FASN, SCD, ADORA1, miR-4332, miR-182, miR-92b-3p, miR-let-7a and miR-let-7e, etc, were key genes or miRNAs regulating lipid deposition. The quantitative expressions of eight DEGs and seven DE miRNAs measured with real-time PCR certified that the results of differential expression genes or miRNAs were reliable. Thus, 18,208 genes and 320 miRNAs were positively expressed in porcine longissimus dorsi muscle. We obtained 85 genes and 18 miRNAs related to muscle growth and 27 genes and 16 miRNAs related to lipid deposition, which provided new insights into molecular mechanism of the economical traits in pig.

Growth rate and meat quality, two economically important traits in pigs, are controlled by multiple genes and biological pathways. In the present study, we performed a proteomic analysis of longissimus dorsi muscle from six-month-old pigs from two Chinese native mini-type breeds (TP and DSP) and two introduced western breeds (YY and LL) using isobaric tag for relative and absolute quantification (iTRAQ). In total, 4,815 peptides corresponding to 969 proteins were detected. Comparison of expression patterns between TP-DSP and YY-LL revealed 288 differentially expressed proteins (DEPs), of which 169 were up-regulated and 119 were down-regulated. Functional annotation suggested that 28 DEPs were related to muscle growth and 15 to lipid deposition. Protein interaction network predictions indicated that differences in muscle growth and muscle fibre between TP-DSP and YY-LL groups were regulated by ALDOC, ENO3, PGK1, PGK2, TNNT1, TNNT3, TPM1, TPM2, TPM3, MYL3, MYH4, and TNNC2, whereas differences in lipid deposition ability were regulated by LPL, APOA1, APOC3, ACADM, FABP3, ACADVL, ACAA2, ACAT1, HADH, and PECI. Twelve DEPs were analysed using parallel reaction monitoring to confirm the reliability of the iTRAQ analysis. Our findings provide new insights into key proteins involved in muscle growth and lipid deposition in the pig.