Geometric Bogomolov conjecture for abelian varieties and some results for those with some degeneration (with an appendix by Walter Gubler: The minimal dimension of a canonical measure)

In this paper, we formulate the geometric Bogomolov conjecture for abelian varieties, and give some partial answers to it. In fact, we insist in a main theorem that under some degeneracy condition, a closed subvariety of an abelian variety does not have a dense subset of small points if it is a non-special subvariety. The key of the proof is the study of the minimal dimension of the components of a canonical measure on the tropicalization of the closed subvariety. Then we can apply the tropical version of equidistribution theory due to Gubler. This article includes an appendix by Walter Gubler. He shows that the minimal dimension of the components of a canonical measure is equal to the dimension of the abelian part of the subvariety. We can apply this result to make a further contribution to the geometric Bogomolov conjecture.Comment: 30 page

Adaptive genomic structural variation in the grape powdery mildew pathogen, Erysiphe necator.

BackgroundPowdery mildew, caused by the obligate biotrophic fungus Erysiphe necator, is an economically important disease of grapevines worldwide. Large quantities of fungicides are used for its control, accelerating the incidence of fungicide-resistance. Copy number variations (CNVs) are unbalanced changes in the structure of the genome that have been associated with complex traits. In addition to providing the first description of the large and highly repetitive genome of E. necator, this study describes the impact of genomic structural variation on fungicide resistance in Erysiphe necator.ResultsA shotgun approach was applied to sequence and assemble the genome of five E. necator isolates, and RNA-seq and comparative genomics were used to predict and annotate protein-coding genes. Our results show that the E. necator genome is exceptionally large and repetitive and suggest that transposable elements are responsible for genome expansion. Frequent structural variations were found between isolates and included copy number variation in EnCYP51, the target of the commonly used sterol demethylase inhibitor (DMI) fungicides. A panel of 89 additional E. necator isolates collected from diverse vineyard sites was screened for copy number variation in the EnCYP51 gene and for presence/absence of a point mutation (Y136F) known to result in higher fungicide tolerance. We show that an increase in EnCYP51 copy number is significantly more likely to be detected in isolates collected from fungicide-treated vineyards. Increased EnCYP51 copy numbers were detected with the Y136F allele, suggesting that an increase in copy number becomes advantageous only after the fungicide-tolerant allele is acquired. We also show that EnCYP51 copy number influences expression in a gene-dose dependent manner and correlates with fungal growth in the presence of a DMI fungicide.ConclusionsTaken together our results show that CNV can be adaptive in the development of resistance to fungicides by providing increasing quantitative protection in a gene-dosage dependent manner. The results of this work not only demonstrate the effectiveness of using genomics to dissect complex traits in organisms with very limited molecular information, but also may have broader implications for understanding genomic dynamics in response to strong selective pressure in other pathogens with similar genome architectures

Chiral Symmetry of Nucleon Resonances in QCD sum rules

The QCD sum rule approach is employed in order to study chiral properties of positive- and negative-parity nucleon resonances. It is pointed out that nucleons with an ``exotic'' chiral property, which can be represented by local five-quark operators, can be paired with a standard nucleon forming a single chiral multiplet. The sum rules of the five-quark operators, however, are shown not to couple strongly to chirally-``exotic'' nucleon resonances at the mass region of less than 2 GeV.Comment: 11 page

Optimizing delivery of therapeutic omega-3 fatty acids for cerebrovascular accidents: designing emulsions by C-13 NMR spectroscopy

OBJECTIVE: Pro-resolving mediators (SPM) are the oxidative products of omega-3 fatty acids which help maintain and control the balance of inflammation and its resolution in the body. Extensive research has shown SPMs can act both chronically and acutely to decrease excessive inflammation and protect against excessive inflammation in cardiovascular disease (atherosclerosis, myocardial infarction, and heart failure). Their powerful effects to resolve inflammation suggest that they will be natural therapeutics for Coronavirus infections and ischemic brain injuries. To optimize mixtures and doses for the fastest and most effective acute delivery of the water-insoluble acylglycerol omega-3 fatty acid (DHA and EPA), we studied fluidity and structural organization in phospholipid membranes by 13C NMR Spectroscopy. METHODS: As models for delivery to cells, acylglycerol omega-3 fatty acids were mixed in increasing proportions with phospholipids and sonicated to make small unilamellar vesicles (SUV) for NMR Spectroscopy. RESULTS: Spectral analysis showed that low proportions (< 5-10 mol %) of omega-3 diglycerides incorporated into the bilayer structure of the phospholipid vesicles without disruption of the bilayer or phase separation. With increases (up to 40mol%) the spectra exhibited separation of the carbonyl peaks and line broadening. With omega-3 triglycerides the narrow aliphatic, glycerol, and carbonyl regions did not exhibit line broadening and were very similar for both omega-3 fatty (DHA or EPA). The olefinic region has the distinct peaks that differentiates one omega-3 fatty acid from the other. Triglyceride mole percentages less than 20mol% that are incorporated into PC emulsions with omega-3 fatty acids do not give detectable signals but at 40mol% we see line broadening of the PC carbonyls. CONCLUSION: At low concentrations of diglycerides with omega-3 fatty acids the vesicle carbonyls were essentially unaffected but at relatively high concentrations they incorporated into the phospholipid vesicles and changed the structural organization at the aqueous interface. In triglycerides with omega-3 fatty acids there was a complete assignment of numerous olefinic peaks, which remained very narrow at all proportions. Comparison of EPA and DHA distinguished the two FA, which will make it possible to quantify whether EPA enters cells more readily, as has been argued because they appear to have better cardiovascular therapeutic effects than DHA in some clinical studies. Acute delivery is feasible with SUVs, but future studies should focus on emulsions with a large triglycerides omega-3 fatty acid core with a greater abundance of triglycerides relative to phospholipid to deliver much larger doses of DHA and EPA

Comparative susceptibility of mosquito populations in North Queensland, Australia to oral infection with dengue virus.

Dengue is the most prevalent arthropod-borne virus, with at least 40% of the world's population at risk of infection each year. In Australia, dengue is not endemic, but viremic travelers trigger outbreaks involving hundreds of cases. We compared the susceptibility of Aedes aegypti mosquitoes from two geographically isolated populations to two strains of dengue virus serotype 2. We found, interestingly, that mosquitoes from a city with no history of dengue were more susceptible to virus than mosquitoes from an outbreak-prone region, particularly with respect to one dengue strain. These findings suggest recent evolution of population-based differences in vector competence or different historical origins. Future genomic comparisons of these populations could reveal the genetic basis of vector competence and the relative role of selection and stochastic processes in shaping their differences. Lastly, we show the novel finding of a correlation between midgut dengue titer and titer in tissues colonized after dissemination

Effect of Hot Water Treatments on Eradication of «Phaeomoniella chlamydospora» and «Phaeoacremonium inflatipes» from Dmant Grapevine Wood

Hot water treatments were applied to eradicate Phaeoacremonium inflatipes and Phaeomoniella chlamydospora from dormant grapevine wood. A thirty-minute hot water treatment at 51°C did not eliminate these pathogens from dormant wood cuttings. Cuttings first inoculated with Pa. chlamydospora or Pm. inflatipes or both fungi, and then subjected to a hot water treatment were either incubated in crispers, or planted for six to eight weeks. Vascular discoloration was scored followed by isolation from the cuttings onto potato dextrose agar amended with 0.1 g l-1 tetracycline (PDA-tet). Isolations confirmed the presence of the pathogens in the inoculated, hot-water treated cuttings as well as in the inoculated, untreated control cuttings. This finding, along with earlier research on the direct effect of hot water on the mycelium of these species, leads to the conclusion that hot water treatments are ineffective in eliminating vine decline pathogens from dormant wood

Association of Spores of «Phaeomoniella chlamydospora», «Phaeoacremonium inflatipes», and «Pm. aleophilum» with Grapevine Cordons in California

Esca (black measles) of grapevine has long been known to occur wherever grapes are grown. Phaeomoniella chlamydospora and two species of Phaeoacremonium, Pm. inflatipes and Pm. aleophilum, have been associated with esca and Petri grapevine decline in major production regions of California. Though present in symptomatic grapevines and capable of causing foliar symptoms of esca, Phaeomoniella chlamydospora does not cause the typical symptoms on fruit. However, trapping studies showed that spores of Pa. chlamydospora, Pm. inflatipes and Pm. aleophilum were captured throughout the year in vineyards ranging from the north California coast to the southern San Joaquin Valley. They can be considered airborne fungi capable of being water-splashed by pruning or other wounds during part of their biological cycle. Trapping of spores coincided with rainfall events for Pa. chlamydospora and Pm. inflatipes, and to a lesser degree for Pm. aleophilum. However, this last species was trapped during periods of time when rainfall did not occur and was trapped longer into the summer