排序方式: 共有47条查询结果,搜索用时 765 毫秒
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Background
Alignment of RNA secondary structures is important in studying functional RNA motifs. In recent years, much progress has been made in RNA motif finding and structure alignment. However, existing tools either require a large number of prealigned structures or suffer from high time complexities. This makes it difficult for the tools to process RNAs whose prealigned structures are unavailable or process very large RNA structure databases. 相似文献43.
Tatiana M. Ovalle Soroush Parsa Maria P. Hernández Luis A. Becerra Lopez‐Lavalle 《Ecology and evolution》2014,4(19):3778-3787
The identification of whitefly species in adult stage is problematic. Morphological differentiation of pupae is one of the better methods for determining identity of species, but it may vary depending on the host plant on which they develop which can lead to misidentifications and erroneous naming of new species. Polymerase chain reaction (PCR) fragment amplified from the mitochondrial cytochrome oxidase I (COI) gene is often used for mitochondrial haplotype identification that can be associated with specific species. Our objective was to compare morphometric traits against DNA barcode sequences to develop and implement a diagnostic molecular kit based on a RFLP‐PCR method using the COI gene for the rapid identification of whiteflies. This study will allow for the rapid diagnosis of the diverse community of whiteflies attacking plants of economic interest in Colombia. It also provides access to the COI sequence that can be used to develop predator conservation techniques by establishing which predators have a trophic linkage with the focal whitefly pest species. 相似文献
44.
Claudio Pandozi Marco Galeazzi Carlo Lavalle Sabina Ficili Maurizio Russo Massimo Santini 《Indian pacing and electrophysiology journal》2010,10(12):556-561
Radiofrequency ablation procedures inside
the left atrial appendage (LAA) are likely to involve
dangerous complications because of a high
thrombogenic effect. Cryoablation procedures are
supposed to be safer. We describe two cases of
successful cryoablation procedures. Two
NavX-guided cryoablations of permanent focal atrial
arrhythmias arising from the LAA were performed.
Left atrial reconstruction and mapping allowed the
zone of the earliest atrial potential to be recorded; the
entire course of the ablation catheter was monitored.
The arrhythmias were successfully ablated; no
thrombotic complications were observed. 相似文献
45.
Carolina Adriana Aguirre‐Morales Evert Thomas Carlos Ivan Cardozo Janeth Gutirrez Carolina Alczar Caicedo Luis Gonzalo Moscoso Higuita Luis Augusto Becerra Lpez‐Lavalle Mailyn Adriana Gonzlez 《Ecology and evolution》2020,10(4):1905-1916
Albizia saman is a multipurpose tree species of seasonally dry tropical forests (SDTFs) of Mesoamerica and northern South America typically cultivated in silvopastoral and other agroforestry systems around the world, a trend that is bound to increase in light of multimillion hectare commitments for forest and landscape restoration. The effective conservation and sustainable use of A. saman requires detailed knowledge of its genetic diversity across its native distribution range of which surprisingly little is known to date. We assessed the genetic diversity and structure of A.saman across twelve representative locations of SDTF in Colombia, and how they may have been shaped by past climatic changes and human influence. We found four different genetic groups which may be the result of differentiation due to isolation of populations in preglacial times. The current distribution and mixture of genetic groups across STDF fragments we observed might be the result of range expansion of SDTFs during the last glacial period followed by range contraction during the Holocene and human‐influenced movement of germplasm associated with cattle ranching. Despite the fragmented state of the presumed natural A. saman stands we sampled, we did not find any signs of inbreeding, suggesting that gene flow is not jeopardized in humanized landscapes. However, further research is needed to assess potential deleterious effects of fragmentation on progeny. Climate change is not expected to seriously threaten the in situ persistence of A. saman populations and might present opportunities for future range expansion. However, the sourcing of germplasm for tree planting activities needs to be aligned with the genetic affinity of reference populations across the distribution of Colombian SDTFs. We identify priority source populations for in situ conservation based on their high genetic diversity, lack or limited signs of admixture, and/or genetic uniqueness. 相似文献
46.
Delphine Amah Ranjana Bhattacharjee Bettina Heider Mathieu Rouard Rony Swennen Luis Augusto Becerra Lopez‐Lavalle Paul D. Fraser 《The Plant journal : for cell and molecular biology》2020,101(6):1258-1268
Roots, tubers, and bananas (RTB) are vital staples for food security in the world's poorest nations. A major constraint to current RTB breeding programmes is limited knowledge on the available diversity due to lack of efficient germplasm characterization and structure. In recent years large‐scale efforts have begun to elucidate the genetic and phenotypic diversity of germplasm collections and populations and, yet, biochemical measurements have often been overlooked despite metabolite composition being directly associated with agronomic and consumer traits. Here we present a compound database and concentration range for metabolites detected in the major RTB crops: banana (Musa spp.), cassava (Manihot esculenta), potato (Solanum tuberosum), sweet potato (Ipomoea batatas), and yam (Dioscorea spp.), following metabolomics‐based diversity screening of global collections held within the CGIAR institutes. The dataset including 711 chemical features provides a valuable resource regarding the comparative biochemical composition of each RTB crop and highlights the potential diversity available for incorporation into crop improvement programmes. Particularly, the tropical crops cassava, sweet potato and banana displayed more complex compositional metabolite profiles with representations of up to 22 chemical classes (unknowns excluded) than that of potato, for which only metabolites from 10 chemical classes were detected. Additionally, over 20% of biochemical signatures remained unidentified for every crop analyzed. Integration of metabolomics with the on‐going genomic and phenotypic studies will enhance ’omics‐wide associations of molecular signatures with agronomic and consumer traits via easily quantifiable biochemical markers to aid gene discovery and functional characterization. 相似文献
47.
Olfactory memory: the long and short of it 总被引:2,自引:2,他引:0
It has been proposed that memory for odors does not have a short-term (or
working) memory system. The distinction between short- and long- term
memory in other sensory modalities has been generally supported by three
main lines of evidence: capacity differences between the proposed systems,
evidence of differential coding, and differential memory losses in
neuropsychological patients. The present paper examines these issues in an
effort to establish a similar distinction for the memory of olfactory
stimuli. Each of these lines of evidence is examined in relation to the
literature on olfactory memory. Based on this examination, it seems that
there is at least preliminary support from each of these lines of evidence
to advocate a distinction between a long- and short-term memory for
olfactory stimuli. Emphasis is placed upon the qualitative similarity of
olfactory memory to other memory systems. This similarity is further
highlighted through an examination of the literature pertinent to serial
position effects in memory for olfactory stimuli.
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