21 research outputs found

    Bacterial leaf streak causes limited yield losses

    No full text
    Bacterial leaf streak seemingly causes no or limited yield losses.Host/Plant: Pearl millet (Pennisetum glaucum)Pest/Path: Bacterial leaf streak (Pest/Pathris pv. pennamericanum

    WoodenHaptics : A Starting Kit for Crafting Force-Reflecting Spatial Haptic Devices

    No full text
    Spatial haptic interfaces have been around for 20 years. Yet, few affordable devices have been produced, and the design space in terms of physical workspace and haptic fidelity of devices that have been produced are limited and discrete. In this paper, an open-source, open-hardware module-based kit is presented that allows an interaction designer with little electro-mechanical experience to manufacture and assemble a fully working spatial haptic interface. It also allows for modification in shape and size as well as tuning of parameters to fit a particular task or application. Results from an evaluation showed that the haptic quality of the WoodenHaptics device was on par with a Phantom Desktop and that a novice could assemble it with guidance in a normal office space. This open source starting kit, uploaded free-to-download online, affords sketching in hardware; it “unsticks” the hardware from being a highly-specialized and esoteric craft to being an accessible and user-friendly technology, while maintaining the feel of high-fidelity haptics.QC 20150420</p

    Parental Effect of DNA (Cytosine-5) Methyltransferase 1 on Grandparental-Origin-Dependent Transmission Ratio Distortion in Mouse Crosses and Human Families

    No full text
    Transmission ratio distortion (TRD) is a deviation from the expected Mendelian 1:1 ratio of alleles transmitted from parents to offspring and may arise by different mechanisms. Earlier we described a grandparental-origin-dependent sex-of-offspring-specific TRD of maternal chromosome 12 alleles closely linked to an imprinted region and hypothesized that it resulted from imprint resetting errors in the maternal germline. Here, we report that the genotype of the parents for loss-of-function mutations in the Dnmt1 gene influences the transmission of grandparental chromosome 12 alleles. More specifically, maternal Dnmt1 mutations restore Mendelian transmission ratios of chromosome 12 alleles. Transmission of maternal alleles depends upon the presence of the Dnmt1 mutation in the mother rather than upon the Dnmt1 genotype of the offspring. Paternal transmission mirrors the maternal one: live-born offspring of wild-type fathers display 1:1 transmission ratios, whereas offspring of heterozygous Dnmt1 mutant fathers tend to inherit grandpaternal alleles. Analysis of allelic transmission in the homologous region of human chromosome 14q32 detected preferential transmission of alleles from the paternal grandfather to grandsons. Thus, parental Dnmt1 is a modifier of transmission of alleles at an unlinked chromosomal region and perhaps has a role in the genesis of TRD

    X chromosome dosage and presence of SRY shape sex-specific differences in DNA methylation at an autosomal region in human cells

    Get PDF
    Abstract Background Sexual dimorphism in DNA methylation levels is a recurrent epigenetic feature in different human cell types and has been implicated in predisposition to disease, such as psychiatric and autoimmune disorders. To elucidate the genetic origins of sex-specific DNA methylation, we examined DNA methylation levels in fibroblast cell lines and blood cells from individuals with different combinations of sex chromosome complements and sex phenotypes focusing on a single autosomal region––the differentially methylated region (DMR) in the promoter of the zona pellucida binding protein 2 (ZPBP2) as a reporter. Results Our data show that the presence of the sex determining region Y (SRY) was associated with lower methylation levels, whereas higher X chromosome dosage in the absence of SRY led to an increase in DNA methylation levels at the ZPBP2 DMR. We mapped the X-linked modifier of DNA methylation to the long arm of chromosome X (Xq13-q21) and tested the impact of mutations in the ATRX and RLIM genes, located in this region, on methylation levels. Neither ATRX nor RLIM mutations influenced ZPBP2 methylation in female carriers. Conclusions We conclude that sex-specific methylation differences at the autosomal locus result from interaction between a Y-linked factor SRY and at least one X-linked factor that acts in a dose-dependent manner
    corecore