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关键词： 樟树   基因组   研究  

ISBN: (纸本)9787539088433

摘要： 本书共分8章,主要内容为樟树全基因组测序及精细图谱构建、樟属植物系统发育分析、樟树萜类化合物合成路径解析、樟树全基因组萜类合成酶基因家族分析等。

摘要： Understanding a species dispersal ecology and population dynamics is essential to effectively manage and conserve a species. As advancing technology improves our knowledge of species movements, it is becoming clear that many species form metapopulations to some extent. A metapopulation is a network of interconnected subpopulations that exchange reproductive individuals with subpopulations occupying nearby patches. Metapopulations have been observed in a variety of species, ranging from plants to vertebrates, and can vary greatly in their dynamics (level of connectivity and gene flow) based on the species behavior and life history strategy. Forming a metapopulation can add much resilience to the subpopulation. A steady inflow of new individuals can protect the subpopulation from inbreeding depression and adds more standing variation for natural selection to work on. However, as the metapopulation breaks down and patches become isolated, that resilience is quickly lost. Habitat fragmentation due to anthropogenic changes poses a significant danger to metapopulations. Understanding these metapopulation dynamics is of key importance to formulating effective and efficient conservation and management plans. Information such as where, when, and how these species are dispersing can tell us how to best preserve these paths and maintain the metapopulation structure. One species that forms a highly extensive metapopulation, is the American goshawk ( Accipiter atricapillus ). In this study we evaluated the metapopulation genomics of American goshawks in the Intermountain West by investigating the genetic diversity and differentiation, as well as gene flow and connectivity, of four subpopulations. The goshawk metapopulation is connected mainly through the natal dispersal of juveniles. Natal dispersal has been and continues to be very hard to track due the technological limitations. Here we show that genomics can offer an alternative when species cannot be easily tracked. While sp

摘要： Poultry farming is a crucial component of the global agriculture industry, providing a significant source of protein and economic livelihoods to millions of people worldwide. However, climate change has led to an increase in extreme weather conditions, including rising temperatures, which can negatively impact poultry production. Heat stress, a physiological response to high temperatures, has been identified as a major challenge affecting poultry health and performance, leading to reduced growth rates, decreased egg production, and increased mortality rates. Understanding the genetic and molecular mechanisms underlying heat stress response in different poultry breeds is essential for developing effective strategies to mitigate its impact on poultry farming. This study aimed to investigate the comparative genomics and transcriptomics of heat stress in chicken and guineafowls from selected countries in Africa, Asia, and Europe. Chicken (Gallus gallus domesticus) and guineafowls (Numida meleagris) are two important poultry breeds widely raised for their meat and egg production, as well as for their cultural significance in various regions of the world. By comparing the genetic and molecular responses to heat stress in these two poultry species from different geographic locations, this study sought to identify candidate genes, and molecular pathways that are associated with heat stress tolerance. This study utilized the "omics" techniques (genomics and transcriptomics), to investigate the signatures of selection for heat stress in chicken, and guineafowls. Three methods: Fixation index (FST), Integrate Haplotype Score (iHS), and Cross-population Extended Haplotype Homozygosity (XP-EHH) were used for the detection of signatures of selection for heat stress. Blood samples from 20 chicken were obtained for whole genome sequencing from Lamu, Kilifi, Mombasa, and Kwale. An additional 14 chicken whole genome sequences were downloaded from the NCBI SRA archive for comparative

摘要： 《食品与生物技术学报》主要发表食品科学与技术、农产品加工与贮藏工程、水产品加工与贮藏工程、食品组分与物性、食品生物技术、食品营养与功能因子、食品安全与质量控制、食品加工与配料、谷物与淀粉工程、油脂与植物蛋白工程、食品资源与综合利用工程、生物技术与发酵工程等学科中具有国际国内领先水平的科学研究论文、食品生物技术领域高水平的学科综述等.

摘要： This dissertation investigates the fungal phylum Ascomycota through computational methodologies, including machine learning, phylogenetics, and comparative genomics. Chapters explore the topics of ecological specialization and the evolutionary dynamics of fungal fruiting bodies and introduce a new method for predicting gene function through machine learning. This work investigation provides valuable insights into the biology, ecology, and genomics of Ascomycota, emphasizing the importance of leveraging bioinformatics for mycological research.

摘要： Quails are increasingly becoming a vital complementary protein source, contributing to food security. In Kenya, the indiscriminate and destructive harvesting of wild African harlequin quails using traditional methods has been ongoing for generations. Yet, their genetic diversity and evolutionary history are largely unknown, thus posing a threat to extinction and genetic diversity. In this study, the genetic variation and demographic history of captured wild African harlequin quails (n = 78) were determined using mitochondrial DNA (mtDNA) and genotyping by sequencing (GBS) data. Selection signatures were also examined using composite likelihood ratio (CLR) and integrated haplotype score (iHS) tests in comparison to domestic Japanese quails (n = 22). Domestic Japanese quail transcriptome data (n = 6) was also examined. The genetic variation in wild African harlequin quails was predominantly among individuals rather than populations. Demographic analyses indicated a signal of rapid expansion. The estimated time since population expansion was 150 to 350 thousand years ago (kya), corresponding to around the Pliocene–Pleistocene boundary. A gradual decline in their effective population size was also observed, which raised concerns about their conservation status. 352 and 424 candidate genes were detected in the wild African harlequin quail and domestic Japanese quail through the CLR test, respectively, whereas 150 and 457 candidate genes were identified through iHS analysis. Candidate genes under positive selection identified in the wild African harlequin quail were associated with important traits such as immune response (MAPK13, CREB1, ITGB3, and PPP1CA) and morphological traits (WNT5A, GRIA1, and ALK), whereas, in domestic Japanese quail, production-related genes such as VIPR2, DYNLL2, PRF1, COL11A1, and GNA12 were identified. RNA-Seq analysis revealed differentially expressed genes associated with production processes such as spermatogenesis and muscle structure devel

摘要： Genomics, transcriptomics, and proteomics are fundamental blocks that shaped modern biology. High throughput and large-scale techniques, such as next-generation sequencing (NGS) and mass spectrometry (MS), have been widely used in the life sciences. Due to the complexity of these data, the analysis needs to be done by sophisticated bioinfor-matic methods. During my doctorate research, I developed new computational methods and applied new strategies to advance the research in genomics, transcriptomics, and proteomics. NGS has brought tremendous and numerous changes to genomic research by providing higher sensitivity, sequencing depth, and throughput compared with traditional sequenc-ing methods, such as Sanger sequencing, qPCR, and microarrays. Benefiting from the advantages of NGS technology, RNA-seq has been widely used for the qualitative and quantitative analysis of genome wide changes in gene expression. Chromatin immuno-precipitation sequencing (ChIP-seq) as another popular application of NGS provides an efficient way to analyze the interaction between proteins and DNA. During my doctoral studies, I used these techniques to uncover the mechanisms behind the hybrid incompat-ibility between Drosophila melanogaster and D. simulans. The loss of HMR in D. melanogaster leads to mitotic defects, increased transcription of transposable elements, and deregulated heterochromatic genes. Through the genome-wide analysis of HMR's localization by ChIP-seq, I found that genomic insulator sites bound by HMR can be grouped into two clusters. One set is composed of gypsy insula-tors, whereas the other is bordered by HP1a-bound areas of active genes. In Hmr mu-tant flies, the transcription of genes belonging to the latter group is severely disrupted in larval tissue and ovaries. These findings showed a novel connection between HMR and insulator proteins, indicating a possible role for genome organization in species devel-opment. Beyond the study of particular genes, and RNA trans

关键词： 加氢脱硫   离子交换   Anderson结构   杂多酸  

摘要： 采用一种简单的阳离子交换方法,将Anderson结构Ni-Mo杂多酸分子中的NH4+交换成Ni^(2+)得到Ni_(2)[NiMo_(6)O_(24)H_(6)](Ni_(3)Mo_(6)),以Ni_(3)Mo_(6)为前体构建加氢脱硫催化剂CAT-Ni_(3)Mo_(6),利用XRD,FTIR,XRF,XPS,SEM,HRTEM等方法对Ni_(3)Mo_(6)和CAT-Ni_(3)Mo_(6)进行表征,并以二苯并噻吩为模型化合物考察了催化剂的性能。实验结果表明,采用阳离子交换方法可将Ni_(3)Mo_(6)中Ni/Mo原子比提高至最佳值0.5,且两种原子处于同一分子中,这使得催化剂中MoS_(2)的分散性更好、NiMoS活性相含量更高,加氢脱硫催化性能更好,催化剂的反应速率常数及催化转化频率分别可达到12.1×10^(-7)mol/(g·s),2.5×10^(-3)s^(-1)。