Long-Term Exposure to High Altitude Affects Voluntary Spatial Attention at Early and Late Processing Stages

The neurocognitive basis of the effect of long-term high altitude exposure on voluntary attention is unclear. Using event related potentials, the high altitude group (people born in low altitude but who had lived at high altitude for 3 years) and the low altitude group (living in low altitude only) were investigated using a voluntary spatial attention discrimination task under high and low perceptual load conditions. The high altitude group responded slower than the low altitude group, while bilateral N1 activity was found only in the high altitude group. The P3 amplitude was smaller in the high altitude compared to the low altitude group only under high perceptual load. These results suggest that long-term exposure to high altitudes causes hemispheric compensation during discrimination processes at early processing stages and reduces attentional resources at late processing stages. In addition, the effect of altitude during the late stage is affected by perceptual load

Integrative Analyses of Transcriptome Sequencing Identify Functional miRNAs in the Chicken Embryo Fibroblasts Cells Infected With Reticuloendotheliosis Virus

In this study, we found a much higher proportion of reticuloendotheliosis virus (REV) infected chicken embryo fibroblasts (CEF) were in active cell division phase than that of control cells which indicated that REV can affect the fate of CEF. So, we performed high-throughput sequencing and transcriptomic analysis to identify functional miRNAs, in order to figure out the possible mechanism in the interaction of REV with CEF. In total, 50 differentially expressed miRNAs (DEmiRNAs) were identified. Then target genes of DEmiRNAs were predicted and identified by transcriptome profile results. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment were conducted to analyze the identified target genes of miRNAs which showed that metabolism, cell cycle, and apoptosis were the most related pathways involved in infection of REV. We analyzed the genes related to cell cycle which indicated that CyclinD1-CDK6 complex played an important role in regulating the transition of the cell cycle from G1 phase to S phase during REV infection. Fluorescence microscope identification showed that REV inhibited the apoptosis of CEF which was in accordance with transcriptome results. A novel miRNA, named novel-72 was found, KEGG analysis was conducted to predict the biological function of its target genes which showed that those target genes were significantly enriched in mTOR signaling pathway and functioned to promote cell cycle and cell growth during the REV infection. In conclusion, REV could induce the up-regulation of cell metabolism, cell cycle and mTOR signaling pathway while inhibit apoptosis of the cell

A Sec-dependent effector, CLIBASIA_04425, contributes to virulence in ‘Candidatus Liberibater asiaticus’

Citrus Huanglongbing (HLB) is the most destructive citrus disease worldwide, mainly caused by ‘Candidatus Liberibacter asiaticus’ (CLas). It encodes a large number of Sec-dependent effectors that contribute to HLB progression. In this study, an elicitor triggering ROS burst and cell death in Nicotiana benthamiana, CLIBASIA_04425 (CLas4425), was identified. Of particular interest, its cell death-inducing activity is associated with its subcellular localization and the cytoplasmic receptor Botrytis-induced kinase 1 (BIK1). Compared with CLas infected psyllids, CLas4425 showed higher expression level in planta. The transient expression of CLas4425 in N. benthamiana and its overexpression in Citrus sinensis enhanced plant susceptibility to Pseudomonas syringae pv. tomato DC3000 ΔhopQ1-1 and CLas, respectively. Furthermore, the salicylic acid (SA) level along with the expression of genes NPR1/EDS1/NDR1/PRs in SA signal transduction was repressed in CLas4425 transgenic citrus plants. Taken together, CLas4425 is a virulence factor that promotes CLas proliferation, likely by interfering with SA-mediated plant immunity. The results obtained facilitate our understanding of CLas pathogenesis

Dynamics and Regulation of RecA Polymerization and De-Polymerization on Double-Stranded DNA

10.1371/journal.pone.0066712PLoS ONE86

Seed production in Caucasian clover (Trifolium ambiguum Bieb.) cv. Monaro : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in the Institute of Natural Resources of Massey University, Palmerston North, New Zealand

A number of factors which may affect seed production in Caucasian clover (Trifolium ambiguum Bieb.) cv. Monaro were investigated viz. root system development and its relationship with seed yield; morphological and reproductive characteristics of different genotypes from within the cultivar; the effects of plant density on seed yield; and, the effects of insect pests on seed yield and quality. Caucasian clover is a rhizomatous legume pasture plant with a large root system. A sand bed was used to investigate root system development and the relationship between the root system and seed yield. During vegetative growth (September to November) root dry matter (DM) accumulated more rapidly than shoot DM, and the root to Shoot ratio was 2.45 by mid November. However as reproductive growth accelerated the rate of root DM accumulation decreased and by early February the root to shoot ratio was 0.65. Plants developed primary, secondary and tertiary crowns in this first growing season, with both primary and secondary crowns producing reproductive shoots. The protracted flowering period (four months) was a result of an initial production of reproductive shoots from primary crowns, and an extended production of reproductive shoots from secondary crowns when primary crown shoot production had ceased. There were therefore two flowering peaks. A single primary crown produced an average seed yield of 3.8 g compared with 0.81 g seed from an average secondary crown. However as there was only one primary crown but 26 secondary crowns per plant, the total seed yield from secondary crowns reached 21.1 g per plant. Root DM was highly correlated (R2 = 0.80-0.97) with the number of leaves, reproductive shoots and inflorescences, as well as the number of secondary crowns. Seed yield per plant was almost entirely dominated by the number and size of the secondary crowns, which in turn depended on the size of the root system prior to reproductive development. The seed production potential of three genotypes selected from within cv. Monaro was investigated. The genotypes differed significantly in their morphological and reproductive characteristics, including the number of reproductive stems and inflorescences produced. Genotypes 2 and 12 had seed yields of 3.65 g and 2.99 g per plant respectively, which genotype 9 had a seed yield of only 0.18 g per plant, primarily because it produced very few inflorescences. Poor inflorescence production by some genotypes within a cultivar will limit seed yield and may alter the genotypic composition of the cultivar as seed multiplication progresses. A radial trial was used to determine the optimal density for seed production of the cultivar. Plant density significantly affected leaf number, reproductive stems, inflorescences number and seed yield per plant in that plants at the highest density (38.2 m-2) produced about 7 times fewer reproductive stems and over 15 times fewer inflorescences per plant compared with those in the lowest density (3.1 m-2). Inflorescence number increased as plant density decreased (R2 = 0.82-0.89). The lowest density plants had the greatest reproductive growth per plant but were not capable of creating the highest reproductive production per unit area. Cultivar Monaro showed a parabolic relationship for reproductive production per unit area with plant density, both for inflorescence number and seed yield m-2. Plants grown at the density of 10.8 plants m-2 produced the highest inflorescence number and seed yield per unit area. The number of inflorescences per plant was the most important seed yield component determining final seed yield in cv. Monaro (R2 = 0.95). Plant density affected seed yield only through reducing inflorescence number; it had no effect on thousand seed weight, or germination and hard seed percentage. It is probable that plant density affects reproductive development through its effects on root system development in Caucasian clover. A semi-radial trial was also used to examine the effects of plant density on seed production of twelve genotypes from within cv. Monaro. These genotypes demonstrated significant differences in reproductive capability. Genotypes 1, 2, 4 and 12 represented a high or normal reproductive capability group compared with others and these genotypes produced inflorescences across all five densities. Genotypes 3, 5, 8, 9, 13 represented another group which either failed to produce or produced only a small number of inflorescences even at the lowest density. Genotypes 6, 7 and 10 were intermediate. Seed yield per plant at the 10.8 plants m-2 density ranged from 0 g for genotypes 5, 8, 9 and 13 to 0.89 g for genotype 1. Reproductive response to plant density did not differ from that when seeds of the cultivar were sown in the full radial trial. Insect pests, particularly thrips (Thripidae) may reduce seed yield and quality. The insecticide taufluvalinate (Mavrik) was applied at 150 ml ha-1 either once (just prior to peak flowering) or every 14 days until harvest, beginning at first inflorescence appearance. Both adults and larvae of onion thrips (Thrips tabaci) and red clover thrips (Haplothrips niger) were detected in inflorescences during peak flowering and seed development. The multiple insecticide applications significantly increased seed number per inflorescence and thousand seed weight, therefore increasing seed yield. However the single application had no effect on seed yield or quality

Can faces affect object-based attention? Evidence from online experiments

This study tested how human faces affect object-based attention (OBA) through two online experiments in a modified double-rectangle paradigm. The results of Experiment 1 revealed that faces did not elicit the OBA effect as non-face objects, which was caused by a longer response time (RT) when attention is focused on faces relative to non-face objects. In addition, by observing faster RTs when attention was engaged horizontally rather than vertically, we found a significant horizontal attention bias, which might override the OBA effect if vertical rectangles were the only items presented; these results were replicated in Experiment 2 (using only vertical rectangles) after directly measuring horizontal bias and excluding its influence on the OBA effect. This study suggested that faces cannot elicit the same-object advantage in the double-rectangle paradigm and provided a method to measure the OBA effect free from horizontal bias

Identification and evaluation of new Ornithopus L. germplasm with special reference to seed characters : a thesis presented in partial fulfilment of the requirement for the degree of Master of Agricultural Science in Seed Technology at Massey University, Palmerston North, New Zealand

Serradella species (Ornithopus L.) are promising annual forage legumes used in many parts of the world, especially in sandy and infertile dryland areas. One hundred and seven accessions of serradella were described and evaluated in Palmerston North , New Zealand. Fifty accessions were part of a 1986 DSIR sponsored forage germplasm collection from Southwest Europe. The rest of the accessions were introduced and/or collected from Australia and New Zealand. The study concentrated on the morphological description and evaluation of agronomic characteristics of the serradella accessions, as well as seed characteristics, including seed development and breaking of hardseed. Four species (Q. sativus, 0. compressus, 0. perousillus and 0. pinnatus) and one subspecies (Q. sativus subsp. isthmocarous) of serradella were identified and described in terms of their morphological characteristics. Morphological characteristics varied less than agronomic characters in serradella. For most accessions seed multiplication was successful. There was a relationship between flowering date and days to maturity, with the days from appearance of the first flower to seed maturity (harvesting date) decreasing as first flower emergence was delayed. Within species some accessions ripened in significantly shorter periods than others. Some had significantly heavier 1000 segment weight than others. In species normally considered to have a characteristic of high hardseed levels, a wide range in percentage hardseed was found among accessions of yellow serradella and slender serradella. In a study of seed development, seed viability of two serradella cultivars Grasslands 'Koba' (Q. sativus) and a 'hybrid' (Q. sativus x 0. compressus) reached a maximum at 32 days after peak flowering. There was no germination unless fresh seed was dried. Hard seed developed at the age of 16 days in the hybrid. Soaking 0. compressus and 0. pinnatus seed in concentrated sulphuric acid for 30 minutes was the optimum treatment for breaking hard seed without causing seed damage