Artificial neural networks reveal efficiency in genetic value prediction

The objective of this study was to evaluate the efficiency of artificial neural networks (ANNs) for predicting genetic value in experiments carried out in randomized blocks. Sixteen scenarios were simulated with different values of heritability (10, 20, 30, and 40%), coefficient of variation (5 and 10%), and the number of genotypes per block (150 and 200 for validation, and 5000 for neural network training). One hundred validation populations were used in each scenario. Accuracy of ANNs was evaluated by comparing the correlation of network value with genetic value, and of phenotypic value with genetic value. Neural networks were efficient in predicting genetic value with a 0.64 to 10.3% gain compared to the phenotypic value, regardless the simulated population size, heritability, or coefficient of variation. Thus, the artificial neural network is a promising technique for predicting genetic value in balanced experiments

Selection in sugarcane based on inbreeding depression

This study aimed to evaluate the gene action associated with yield-related traits, including mean stalk weight (MSW), tons of sugarcane per hectare (TCH), and fiber content (FIB) in sugarcane. Moreover, the viability of individual reciprocal recurrent selection (RRSI-S1) was verified, and the effect of inbreeding depression on progenies was checked. The results were also used to select promising genotypes in S1 progenies. Eight clones (RB925345, RB867515, RB739359, SP80-1816, RB928064, RB865230, RB855536, and RB943365) and their respective progenies, derived from selfing (S1), were evaluated. Several traits, including the number of stalks, MSW, soluble solids content determined in the field, stalk height, stalk diameter, TCH, soluble solids content determined in the laboratory, sucrose content, and FIB were evaluated in a randomized block design with hierarchical classification. The results showed that the traits with predominant gene action associated with the dominance variance of MSW and TCH were most affected by inbreeding depression. The FIB, with predominant additive control, was not affected by selfing of the clones, and the RB867515⊗, RB928064⊗, RB739359⊗ and RB925345⊗ progenies performed best. Therefore, the use of S1 progenies for RRSI-S1 in sugarcane breeding programs is promising, and it should be explored for the future breeding of clones with high FIB levels

A More Flavored Higgs boson in Supersymmetric models

A More flavored Higgs boson arises when the flavor structure encoded in SUSY extensions of the SM is transmited to the Higgs sector. The flavor-Higgs transmition mechanism can have a radiative or mixing origin, as it is illustrated with several examples, and can produce interesting Higgs signatures that can be probed at future high-energy colliders. Within the MSSM, the flavor mediation mechanism can be of radiative type, as it is realized trhough gaugino-slepton loops, which transmit the flavor structture of the soft-breaking sector to the Higgs bosons. In particular we focus on evaluating the contributions from the general trilinear terms to the lepton flavor violating Higgs (LFV) vertices. On the other hand, as an example of flavor mediation through mixing, we discuss an E_6 inspired multi-Higgs model, with an abelian flavor symmetry, where LFV as well as lepton flavor conserving Higgs effects are found to arise, though in this case at tree-level. We find that Tevatron and LHC can provide information on the flavor structure of these models through the detection of the LFV higgs mode h-> tau+mu, while NLC can perform high-precision measurements of the LFC mode h-> tau tau.Comment: 17 pages, 5 tables, 3 figures; corrected mistake in last section, results changed but conclusions remmai

In-solution Y-chromosome capture-enrichment on ancient DNA libraries.

As most ancient biological samples have low levels of endogenous DNA, it is advantageous to enrich for specific genomic regions prior to sequencing. One approach-in-solution capture-enrichment-retrieves sequences of interest and reduces the fraction of microbial DNA. In this work, we implement a capture-enrichment approach targeting informative regions of the Y chromosome in six human archaeological remains excavated in the Caribbean and dated between 200 and 3000 years BP. We compare the recovery rate of Y-chromosome capture (YCC) alone, whole-genome capture followed by YCC (WGC + YCC) versus non-enriched (pre-capture) libraries. The six samples show different levels of initial endogenous content, with very low (< 0.05%, 4 samples) or low (0.1-1.54%, 2 samples) percentages of sequenced reads mapping to the human genome. We recover 12-9549 times more targeted unique Y-chromosome sequences after capture, where 0.0-6.2% (WGC + YCC) and 0.0-23.5% (YCC) of the sequence reads were on-target, compared to 0.0-0.00003% pre-capture. In samples with endogenous DNA content greater than 0.1%, we found that WGC followed by YCC (WGC + YCC) yields lower enrichment due to the loss of complexity in consecutive capture experiments, whereas in samples with lower endogenous content, the libraries' initial low complexity leads to minor proportions of Y-chromosome reads. Finally, increasing recovery of informative sites enabled us to assign Y-chromosome haplogroups to some of the archeological remains and gain insights about their paternal lineages and origins. We present to our knowledge the first in-solution capture-enrichment method targeting the human Y-chromosome in aDNA sequencing libraries. YCC and WGC + YCC enrichments lead to an increase in the amount of Y-DNA sequences, as compared to libraries not enriched for the Y-chromosome. Our probe design effectively recovers regions of the Y-chromosome bearing phylogenetically informative sites, allowing us to identify paternal lineages with less sequencing than needed for pre-capture libraries. Finally, we recommend considering the endogenous content in the experimental design and avoiding consecutive rounds of capture, as clonality increases considerably with each round

Increasing genetic variability in black oats using gamma irradiation

The black oat (Avena strigosa Schreb) is commonly used for forage, soil cover, and green manure. Despite its importance, little improvement has been made to this species, leading to high levels of genotypic disuniformity within commercial cultivars. The objective of this study was to evaluate the efficiency of different doses of gamma rays [ ^60 Co] applied to black oat seeds on the increase of genetic variability of agronomic traits. We applied doses of 0, 10, 50, 100, and 200 Gy to the genotype ALPHA 94087 through exposure to [ ^60 Co]. Two experiments were conducted in the winter of 2008. The first aimed to test forage trait measurements such as plant height, dry matter yield, number of surviving tillers, and seedling stand. The second test assessed seed traits, such as yield and dormancy levels. Gamma irradiation seems not to increase seed yield in black oats, but it was effective in generating variability for the other traits. Tiller number and plant height are important selection traits to increase dry matter yield. Selection in advanced generations of mutant populations can increase the probability of identifying superior genotypes

Synthesis and characterization of polymer/silica/QDs fluorescent nanocomposites with potential application as printing toner

In this work cadmium telluride quantum dots (CdTeQDs) were prepared via one-pot synthesis microwave assisted. Afterwards, CdTeQDs/silica (SiO2)/nigrosine (nigro)/poly (styrene co-methyl methacrylate) (PSCMM) fluorescent nanocomposite (CSNP) powders were prepared via ultrasonic treatment and post drying at 60 °C. The samples were characterized by UV-vis absorbance, x-ray diffraction (XRD) and transmission electron microscopy (TEM). Finally, successful printing tests were performed on security paper at 130 °C. These results show the potential of this nanocomposite to be used as security toner. This printing toner configuration is reported for first time

Mass matrix Ansatz and lepton flavor violation in the THDM-III

Predictive Higgs-fermion couplings can be obtained when a specific texture for the fermion mass matrices is included in the general two-Higgs doublet model. We derive the form of these couplings in the charged lepton sector using a Hermitian mass matrix Ansatz with four-texture zeros. The presence of unconstrained phases in the vertices phi-li-lj modifies the pattern of flavor-violating Higgs interactions. Bounds on the model parameters are obtained from present limits on rare lepton flavor violating processes, which could be extended further by the search for the decay tau -> mu mu mu and mu-e conversion at future experiments. The signal from Higgs boson decays phi -> tau mu could be searched at the large hadron collider (LHC), while e-mu transitions could produce a detectable signal at a future e mu-collider, through the reaction e mu -> h0 -> tau tau.Comment: 17 pages, 9 figure