85 research outputs found

    Optimization of Regeneration Protocol and Agrobacterium Mediated Transformation in Carnation (Dianthus caryophyllus L.)

    Get PDF
    An efficient and reproducible regeneration protocol for carnation genotypes Arka Flame and IIHRS-1 has been developed from leaf and stem explants. Although IIHRS-1 showed slightly higher regeneration (55%) compared to Arka Flame (49.2%), there was no significant difference in their regeneration response. However, significant difference in regeneration potential was observed with leaf explant exhibiting higher regeneration potential (5.5 shoots/explant) as compared to (4.9) stem explant. Among various plant growth regulator combinations tested for regeneration, the best regeneration response and maximum regeneration potential was obtained in MS medium supplemented with NAA (0.1 mg/l) and TDZ (1.0mg /l) for both the explants and genotypes used. The medium also proved suitable for inducing elongation of regenerated shoots. Rooting of in vitro formed shootlets could be induced at greater frequency in MS medium supplemented with IAA (1.0 mg/l). Based on this protocol, transformation was carried out in genotype IIHRS-1 using leaf explants with Agrobacterium tumefaciens LBA 4404 with binary vector pROK2 containing baculovirus chitinase gene under the control of 35S promoter with npt II serving as selectable marker. There was regeneration of putative transformants at a frequency of 28.9%. However, great difficulty was encountered in rooting of shoots. Hence a few shoots regenerated on selection medium at random were tested for transgene integration. Out of the three shoots tested for npt II amplification, two shoots tested positive. The presence of transgene was confirmed through PCR amplification of npt II gene and dot blot analysis of chitinase gene

    Biochemical characterization of defense responses in rose genotypes in response to artificial inoculation with black spot pathogen Diplocarpon rosae

    Get PDF
    Resistance responses in the leaves of eight rose genotypes, Knock Out (highly resistant), Arka Nishkant (moderately resistant), R. multiflora (highly susceptible), Arka Swadesh (highly susceptible), IIHRR 13-4 (susceptible), Arka Parimala (susceptible), R. indica (susceptible) and IIHRR 4-15-12 (moderately susceptible), exhibiting varied levels of resistance against black spot were investigated post artificial inoculation with black spot pathogen, Diplocarpon rosae. There was consistent increase in the activities of defense related enzymes such as catalase, peroxidase, polyphenol oxidase, superoxide dismutase and phenylalanine ammonia lyase and other defense related secondary metabolites like phenols and flavonoids at different phases of black spot progression and increase was high in resistant genotypes Knock Out and Arka Nishkant. The peak activity of defense enzymes and high concentration of other metabolites was witnessed during early stages of infection in the resistant genotypes while it was during later phase in the susceptible genotypes. These results suggested that the faster and stronger activation of defense system is associated with the resistance against black spotin the rose genotypes

    Lifetime of 19Ne*(4.03 MeV)

    Get PDF
    The Doppler-shift attenuation method was applied to measure the lifetime of the 4.03 MeV state in 19Ne. Utilizing a 3He-implanted Au foil as a target, the state was populated using the 20Ne(3He,alpha)19Ne reaction in inverse kinematics at a 20Ne beam energy of 34 MeV. De-excitation gamma rays were detected in coincidence with alpha particles. At the 1 sigma level, the lifetime was determined to be 11 +4, -3 fs and at the 95.45% confidence level the lifetime is 11 +8, -7 fs.Comment: 6 pages, submitted to Phys. Rev.

    Lifetimes of states in 19Ne above the 15 O + alpha breakup threshold

    Full text link
    The 15O(alpha,gamma)19Ne reaction plays a role in the ignition of Type I x-ray bursts on accreting neutron stars. The lifetimes of states in 19Ne above the 15O + alpha threshold of 3.53 MeV are important inputs to calculations of the astrophysical reaction rate. These levels in 19Ne were populated in the 3He(20Ne,alpha)19Ne reaction at a 20Ne beam energy of 34 MeV. The lifetimes of six states above the threshold were measured with the Doppler shift attenuation method (DSAM). The present measurements agree with previous determinations of the lifetimes of these states and in some cases are considerably more precise

    Carbon Isotopes Near Drip Lines in the Relativistic Mean-Field Theory

    Get PDF
    We have investigated the ground-state properties of carbon isotopes in the framework of the relativistic mean-field (RMF) theory. RMF calculations have been performed with the non-linear scalar self-coupling of the σ\sigma meson using an axially symmetric deformed configuration. We have also introduced the vector self-coupling of the ω\omega meson for the deformed mean-field calculations. The results show that the RMF predictions on radii and deformations are in good agreement with the available experimental data. It is shown that several carbon isotopes possess a highly deformed shape akin to a superdeformation. The single-particle structure of nuclei away from the stability line has been discussed with a view to understand the properties near the neutron drip line. Predictions of properties of carbon isotopes away from the stability line are made.Comment: Revtex, 29 pages, 11 postscript figures include

    Measurement of two-halo neutron transfer reaction p(11^{11}Li,9^{9}Li)t at 3AA MeV

    Get PDF
    The p(\nuc{11}{Li},\nuc{9}{Li})t reaction has been studied for the first time at an incident energy of 3AA MeV delivered by the new ISAC-2 facility at TRIUMF. An active target detector MAYA, build at GANIL, was used for the measurement. The differential cross sectionshave been determined for transitions to the \nuc{9}{Li} ground andthe first excited states in a wide range of scattering angles. Multistep transfer calculations using different \nuc{11}{Li} model wave functions, shows that wave functions with strong correlations between the halo neutrons are the most successful in reproducing the observation.Comment: 6 pages, 3 figures, submitted to Physical Review Letter

    Shell Effects in Nuclei with Vector Self-Coupling of Omega Meson in Relativistic Hartree-Bogoliubov Theory

    Full text link
    Shell effects in nuclei about the stability line are investigated within the framework of the Relativistic Hartree-Bogoliubov (RHB) theory with self-consistent finite-range pairing. Using 2-neutron separation energies of Ni and Sn isotopes, the role of σ\sigma- and ω\omega-meson couplings on the shell effects in nuclei is examined. It is observed that the existing successful nuclear forces (Lagrangian parameter sets) based upon the nonlinear scalar coupling of σ\sigma-meson exhibit shell effects which are stronger than suggested by the experimental data. We have introduced nonlinear vector self-coupling of ω\omega-meson in the RHB theory. It is shown that the inclusion of the vector self-coupling of ω\omega-meson in addition to the nonlinear scalar coupling of σ\sigma-meson provides a good agreement with the experimental data on shell effects in nuclei about the stability line. A comparison of the shell effects in the RHB theory is made with the Hartree-Fock Bogoliubov approach using the Skyrme force SkP. It is shown that the oft-discussed shell quenching with SkP is not consistent with the available experimental data.Comment: 34 pages latex, 18 ps figures, replaced with minor corrections in some figures, accepted for publication in Phys. Rev.

    A Clustering Approach for Autism based Autistic Trait Classification

    Get PDF
    Machine learning (ML) techniques can be utilized by physicians, clinicians, as well as other users, to discover Autism Spectrum Disorder (ASD) symptoms based on historical cases and controls to enhance autism screening efficiency and accuracy. The aim of this study is to improve the performance of detecting ASD traits by reducing data dimensionality and eliminating redundancy in the autism dataset. To achieve this, a new semi-supervised ML framework approach called Clustering-based Autistic Trait Classification (CATC) is proposed that uses a clustering technique and validation of the classifiers is done by classification techniques. The proposed method identifies potential autism cases based on their similarity traits as opposed to a scoring function used by many ASD screening tools. Empirical results on different datasets involving children, adolescents, and adults were verified and compared to other common machine learning classification techniques. The results showed that CATC offers classifiers with higher predictive accuracy, sensitivity, and specificity rates than those of other intelligent classification approaches such as Artificial Neural Network (ANN), Random Forest, and Random Trees, and Rule Induction. These classifiers are useful as they are exploited by diagnosticians and other stakeholders involved in ASD screening

    Breeding tomato (Solanum lycopersicum L.) for resistance to biotic and abiotic stresses

    Get PDF
    Tomato (Solanum lycopersicum L.) is an important vegetable crop cultivated in the tropical and sub-tropical regions of the world. Low productivity in India is due to occurrence of both biotic and abiotic stresses. Among the biotic stresses, tomato leaf curl disease, bacterial wilt, early blight and Groundnut Bud Necrosis Virus disease have become serious production constraints causing considerable yield loss in the major tomato growing areas of the country. Adoption of multiple disease resistant varieties or F1 hybrids would be the most appropriate way to address these diseases. At ICAR-IIHR, Bengaluru systematic breeding strategies were employed to pyramid genes for resistance to early blight, bacterial wilt and tomato leaf curl diseases and to develop advanced breeding lines& F1 hybrids with triple disease resistance. Stable source of resistance to early blight and bi-partite begomo-virus (Tomato Leaf Curl New Delhi Virus) has been identified in Solanum habrochaites LA-1777. Validation with molecular markers linked to tomato leaf curl virus resistance revealed that LA-1777 carryTy2 and other putative resistant genes. Several high yielding dual purpose hybrids were also developed for fresh market and processing with high level of resistance to multiple diseases. Cherry tomato lines have also been bred for high TSS, total carotenoids, total phenols, flavonoids, vitamin C, acidity and lycopene content. IIHR-249-1, IIHR-2101 (Solanum habrochaites LA-1777), IIHR- 2866 and IIHR-2864 recorded high values for quality parameters like total carotenoids, lycopene, vitamin C, total phenols, flavonoids and TSS. Drought tolerant root stock has been developed by an interspecific cross between S. habrochaites LA-1777 and S. lycopersicum (15 SB SB). Resistant sources have also been identified against Tuta absoluta, a serious insect pest reported from major tomato growing areas in the country in recent time. High temperature tolerant breeding lines are in pipe line

    Dysregulated Nephrin in Diabetic Nephropathy of Type 2 Diabetes: A Cross Sectional Study

    Get PDF
    Podocyte specific proteins are dysregulated in diabetic nephropathy, though the extent of their expression loss is not identical and may be subject to different regulatory factors. Quantifying the degree of loss may help identify the most useful protein to use as an early biomarker of diabetic nephropathy.Protein expression of synaptopodin, podocin and nephrin were quantified in 15 Type 2 diabetic renal biopsies and 12 control patients. We found statistically significant downregulation of synaptopodin (P<0.0001), podocin (P = 0.0002), and nephrin (P<0.0001) in kidney biopsies of diabetic nephropathy as compared with controls. Urinary nephrin levels (nephrinuria) were then measured in 66 patients with Type 2 diabetes and 10 healthy controls by an enzyme-linked immunosorbent assay (Exocell, Philadelphia, PA). When divided into groups according to normo-, micro-, and macroalbuminuria, nephrinuria was found to be present in 100% of diabetic patients with micro- and macroalbuminuria, as well as 54% of patients with normoalbuminuria. Nephrinuria also correlated significantly with albuminuria (rho = 0.89, p<0.001), systolic blood pressure (rho = 0.32, p = 0.007), and correlated negatively with serum albumin (rho = -0.48, p<0.0001) and eGFR (rho = -0.33, p = 0.005).These data suggest that key podocyte-specific protein expressions are significantly and differentially downregulated in diabetic nephropathy. The finding that nephrinuria is observed in a majority of these normoalbuminuric patients demonstrates that it may precede microalbuminuria. If further research confirms nephrinuria to be a biomarker of pre-clinical diabetic nephropathy, it would shed light on podocyte metabolism in disease, and raise the possibility of new and earlier therapeutic targets
    corecore