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961.
We present an initial attempt for the development of a distributed and scalable GIS-like tool for the storage, selection and
visualization of 4D marine datasets. The aim of this tool is to standardize the variety of data available for the water column
and support non-technical marine biologists in manipulating 4D marine datasets. The tool is developed towards answering specific
environmental and biological questions regarding ocean processes and essential fish habitat mapping in three dimensions.
Guest editor: V. D. Valavanis
Essential Fish Habitat Mapping in the Mediterranean 相似文献
962.
采用第二代Illumina HiSeq测序技术对闽楠的木质部、韧皮部、叶片进行转录组测序,分别获得Clean Reads片段41 383 707条、43 343 922条、44 191 586条,经转录本拼接后得到序列总长度达120 535 288 bp的383 331条Conting片段,进一步组装得到平均长度为542 bp的151 729条Unigenes。将闽楠转录组Unigenes进行基因功能注释,与NR数据库比对发现,其与葡萄的相似序列最多(34%),与黄瓜、野草莓、大豆的同源性较低(各占3%);进行GO功能注释,可将其划分为生物过程、细胞成分、分子功能3大类共计52个分支,与eggNOG数据库比对可分为25类,通过KEGG功能注释可知转录组中涉及的基因共参与了176条代谢通路,其中核糖体和碳代谢获得的注释较多。另外通过MISA软件分析,共获得35 972个SSR位点。其中,单核苷酸、二核苷酸和三核苷酸为优势重复类型,SSR位点数分别为21 762(60.50%),8 931(24.83%),4 924(13.69%)。闽楠转录组分析及基因功能注释为深入开展闽楠遗传育种及分子生物学相关研究奠定基础。 相似文献
963.
A circular code is a set of trinucleotides allowing the reading frames in genes to be retrieved locally, i.e. anywhere in genes and in particular without start codons, and automatically with a window of few nucleotides. In 1996, a common circular code, called X, was identified in large populations of eukaryotic and prokaryotic genes. Hence, it is believed to be an ancestral structural property of genes. A new computational approach based on comparative genomics is developed to identify essential molecular functions associated with circular codes. It is based on a quantitative and sensitive statistical method (FPTF) to identify three permuted trinucleotide sets in the three frames of genes, a flower automaton algorithm to determine if a trinucleotide set is a circular code or not, and an integrated Gene Ontology and Taxonomy (iGOT) database. By carrying out automatic circular code analyses on a huge number of gene populations where each population is associated with a particular molecular function, it identifies 266 gene populations having circular codes close to X. Surprisingly, their molecular functions include 98% of those covered by the essential genes of the DEG database (Database of Essential Genes). Furthermore, three trinucleotides GTG, AAG and GCG, replacing three trinucleotides of the code X and called “evolutionary” trinucleotides, significantly occur in these 266 gene populations. Finally, a new method developed to analyse and quantify the stability of a set of trinucleotides demonstrates that these evolutionary trinucleotides are associated with a significant increase of the stability of the common circular code X. Indeed, its stability increases from the 1502th rank to the 16th rank after the replacement of the three evolutionary trinucleotides among 9920 possible trinucleotide replacement sets. 相似文献
964.
The process of heat regulation is complex and its exact molecular mechanism is not fully understood. In this study, to investigate the global gene regulation response to acute heat exposure, gene microarrays were exploited to analyze the effects of heat stress on three tissues (brain, liver, leg muscle) of the yellow broiler chicken (Gallus gallus). We detected 166 differentially expressed genes (DEGs) in the brain, 219 in the leg muscle and 317 in the liver. Six of these genes were differentially expressed in all three tissues and were validated by qRT-PCR, and included heat shock protein genes (HSPH1, HSP25), apoptosis-related genes (RB1CC1, BAG3), a cell proliferation and differentiation-related gene (ID1) and the hunger and energy metabolism related gene (PDK). All these genes might be important factors in chickens suffering from heat stress. We constructed gene co-expression networks using the DEGs of the brain, leg muscle and liver and two, four and two gene co-expression modules were identified in these tissues, respectively. Functional enrichment of these gene modules revealed that various functional clusters were related to the effects of heat stress, including those for cytoskeleton, extracellular space, ion binding and energy metabolism. We concluded that these genes and functional clusters might be important factors in chickens under acute heat stress. Further in-depth research on the newly discovered heat-related genes and functional clusters is required to fully understand their molecular functions in thermoregulation. 相似文献
965.
Jennifer M. Fernandez Kristi L. Poling Amar D. Desai Jenna E. Koblinski Mark Borgstrom Ivo Abraham Sara Behbahani 《Pigment cell & melanoma research》2023,36(1):42-52
Melanoma in Black patients carries a poor prognosis. Due to its rarity, melanoma in this population has not been well characterized. This study evaluates survival predictors in Black patients with melanoma. This was a retrospective cohort study of Black patients with cutaneous melanoma from the National Cancer Database 2004–2018. Of the 2464 cases, melanoma was more common among females than males (57.1% vs. 42.9%, p < .001). Median Breslow depth was 1.8 mm (interquartile range 0.4–4.4). Lower extremities were the most common location (52.8%), followed by upper extremities (13.1%) along with otherwise specified/overlapping/other (13.1%), then by trunk (11.8%), and lastly head and neck (9.2%). Stage at diagnosis was I (30.7%), II (27.5%), III (24.1%), and IV (17.7%). Ulceration was observed in 41.4% of lesions. Acral lentiginous melanoma (ALM) was the most common specific histologic subtype (20.3%), followed by superficial spreading melanoma (9.4%). After adjusting for confounders, higher stages and primary site on the head and neck were the strongest independent predictors of worse overall survival. Melanoma in Black patients is most likely to appear on the lower extremities. A large portion (41.8%) presented with stage III or IV disease. ALM was the most common specific histologic subtype. 相似文献
966.
Suzette G. A. Flantua Ondrej Mottl Vivian A. Felde Kuber P. Bhatta Hilary H. Birks John-Arvid Grytnes Alistair W. R. Seddon H. John B. Birks 《Global Ecology and Biogeography》2023,32(8):1377-1394
Aim
Palaeoecological data are crucial for comprehending large-scale biodiversity patterns and the natural and anthropogenic drivers that influence them over time. Over the last decade, the availability of open-access research databases of palaeoecological proxies has substantially increased. These databases open the door to research questions needing advanced numerical analyses and modelling based on big-data compilations. However, compiling and analysing palaeoecological data pose unique challenges that require a guide for producing standardized and reproducible compilations.Innovation
We present a step-by-step guide of how to process fossil pollen data into a standardized dataset compilation ready for macroecological and palaeoecological analyses. We describe successive criteria that will enhance the quality of the compilations. Though these criteria are project and research question-dependent, we discuss the most important assumptions that should be considered and adjusted accordingly. Our guide is accompanied by an R-workflow—called FOSSILPOL—and corresponding R-package—called R-Fossilpol—that provide a detailed protocol ready for interdisciplinary users. We illustrate the workflow by sourcing and processing Scandinavian fossil pollen datasets and show the reproducibility of continental-scale data processing.Main Conclusions
The study of biodiversity and macroecological patterns through time and space requires large-scale syntheses of palaeoecological datasets. The data preparation for such syntheses must be transparent and reproducible. With our FOSSILPOL workflow and R-package, we provide a protocol for optimal handling of large compilations of fossil pollen datasets and workflow reproducibility. Our workflow is also relevant for the compilation and synthesis of other palaeoecological proxies and as such offers a guide for synthetic and cross-disciplinary analyses with macroecological, biogeographical and palaeoecological perspectives. However, we emphasize that expertise and informed decisions based on palaeoecological knowledge remain crucial for high-quality data syntheses and should be strongly embedded in studies that rely on the increasing amount of open-access palaeoecological data. 相似文献967.
介绍一种用VB软件编写的数据库管理软件,用于《韦氏学龄儿童智力量表(WISC-R)和婴儿~初中学生社会生活能力量表(日本S-M社会生活能力检查修订版)》的计算机评价与统计。该软件操作简单,评价准确,携带方便,是一种专用的少儿智力测评软件。 相似文献
968.
969.
《Current biology : CB》2022,32(23):5209-5218.e5
970.
《遗传、选种与进化》2007,39(6):651-668
The aim of this paper was to describe, and when possible compare, the multivariate methods used by the participants in the EADGENE WP1.4 workshop. The first approach was for class discovery and class prediction using evidence from the data at hand. Several teams used hierarchical clustering (HC) or principal component analysis (PCA) to identify groups of differentially expressed genes with a similar expression pattern over time points and infective agent (E. coli or S. aureus). The main result from these analyses was that HC and PCA were able to separate tissue samples taken at 24 h following E. coli infection from the other samples. The second approach identified groups of differentially co-expressed genes, by identifying clusters of genes highly correlated when animals were infected with E. coli but not correlated more than expected by chance when the infective pathogen was S. aureus. The third approach looked at differential expression of predefined gene sets. Gene sets were defined based on information retrieved from biological databases such as Gene Ontology. Based on these annotation sources the teams used either the GlobalTest or the Fisher exact test to identify differentially expressed gene sets. The main result from these analyses was that gene sets involved in immune defence responses were differentially expressed. 相似文献