Antifungal acetylinic thiophenes from Tagetes minuta: potential biopesticide

Apart from thiophenes, which possess wide range of biocidal activity, aerial parts of Tagetes sp. contain essential oil. Oil components were reported to have antifungal activity, thus making whole plant of Tagetes very useful for exploiting as natural fungistatic agent. In the present study, Tagetes minuta grown in north western Himalayan condition were evaluated for its potential for use as antifungal agent. Flower essential oil showed minimal antifungal activity. Whereas, leaf essential oil was found signifi cant antifungal activity against three phytopathogenic fungi out of eight tested fungi. ED50 values were 165, 175 and 110 μg mL-1 against Rhizoctonia solani, Sclerotinia sclerotiorum and Sclerotium rolfsii, respectively. Thiophene rich extract of Tagetes minuta was found comparatively lesser active (ED50: 233-484 μg mL-1) than leaf essential oil against the same fungi. The present study shows that essential oil from leaves and thiophene rich extracts from marigold roots have signifi cantly good antifungal activity against a number of soil borne and foliar plant pathogens. The easy availability of these plants makes it an attractive potential candidate for development of natural fungicide

Identification of 13 Cepheids and 333 Other Variables in M31

We present Cousins $R$ and $I$ band photometry of variable stars in a $\sim13'\times 13'$ region in the disk of M31 galaxy, obtained during 141 nights. Of the 26 Cepheid variables present in the region, two are newly discovered, 11 are classified as Cepheids for the first time and 13 are confirmed as Cepheids. The extensive photometry of these Cepheids enabled us to determine precise phase and amplitude of pulsation which ranges from 0.11 to 0.48 mag in $R$ band. The period of variability ranges from $\sim$7.5 to 56 days. The period-luminosity diagram is used to derive a distance modulus of 24.49$\pm$0.11 mag for M31 galaxy. We also report variability in 333 other stars, of them, 115 stars appear to be long period variables, 2 suspected eclipsing binaries and remaining 216 are irregular variables.Comment: Accepted for publication in A&A, 9 figures, the paper and figures with better resolution can be downloaded from http://cdfinfo.in2p3.fr/Downloads/cosmobs/yogesh/paper

Fusion cross sections for 6,7Li + 24Mg reactions at energies below and above the barrier

Measurement of fusion cross sections for the 6,7Li + 24Mg reactions by the characteristic gamma-ray method has been done at energies from below to well above the respective Coulomb barriers. The fusion cross sections obtained from these gamma-ray cross sections for the two systems are found to agree well with the total reaction cross sections at low energies. The decrease of fusion cross sections with increase of energy is consistent with the fact that other channels, in particular breakup open up with increase of bombarding energy. This shows that there is neither inhibition nor enhancement of fusion cross sections for these systems at above or below the barrier. The critical angular momenta (lcr) deduced from the fusion cross sections are found to have an energy dependence similar to other Li - induced reactions.Comment: 1 .pdf fil

Small Quadrupole Deformation for the Dipole Bands in 112In

High spin states in $^{112}$In were investigated using $^{100}$Mo($^{16}$O, p3n) reaction at 80 MeV. The excited level have been observed up to 5.6 MeV excitation energy and spin $\sim$ 20$\hbar$ with the level scheme showing three dipole bands. The polarization and lifetime measurements were carried out for the dipole bands. Tilted axis cranking model calculations were performed for different quasi-particle configurations of this doubly odd nucleus. Comparison of the calculations of the model with the B(M1) transition strengths of the positive and negative parity bands firmly established their configurations.Comment: 10 pages, 11 figures, 2 table

Baseline status and effect of genotype, environment and genotype × environment interactions on iron and zinc content in Indian chickpeas (Cicer arietinum L.)

Genetic biofortification is a cost-effective strategy to address iron (Fe) and zinc (Zn) deficiencies prevalent worldwide. Being a rich and cheap protein source, chickpea, a food legume grown and consumed across the globe, is a good target for biofortification. Nineteen popular commercial cultivars of India were analysed for Fe and Zn content at four locations representing different agro-climatic zones to study the genotypic and genotype 9 environment interactions on Fe and Zn. Distribution of phytic acid (PA), an important anti-nutrient that chelates and reduces the mineral bioavailability, was also analysed. Influence of other agronomic traits like days to flowering, plant height and 100 seed weight on Fe and Zn content was also studied. All the traits showed significant G and G 9 E interactions; however, the magnitude of variance of GXE was lesser than that of G alone. Genotype ? genotype-by-environment and genotype- by-trait biplots were used to assess the relations between different environments, genotypes and traits. Iron and zinc content showed positive correlation between them indicating a possibility of their coselection in breeding. A negative correlation between Zn and PA was observed. However, there was very low variability for PA content in the cultivars under study, indicating that moderate PA is naturally selected in these cultivars during breeding. Despite significant GXE interactions, cultivars with high Fe ([70 lg/g) and Zn content ([40 lg/g) at three out of four test locations were identified. Such genotypes will be useful in breeding programs for enhancing mineral micronutrient content and understanding the molecular mechanisms governing their differential uptake

Massive stars as thermonuclear reactors and their explosions following core collapse

Nuclear reactions transform atomic nuclei inside stars. This is the process of stellar nucleosynthesis. The basic concepts of determining nuclear reaction rates inside stars are reviewed. How stars manage to burn their fuel so slowly most of the time are also considered. Stellar thermonuclear reactions involving protons in hydrostatic burning are discussed first. Then I discuss triple alpha reactions in the helium burning stage. Carbon and oxygen survive in red giant stars because of the nuclear structure of oxygen and neon. Further nuclear burning of carbon, neon, oxygen and silicon in quiescent conditions are discussed next. In the subsequent core-collapse phase, neutronization due to electron capture from the top of the Fermi sea in a degenerate core takes place. The expected signal of neutrinos from a nearby supernova is calculated. The supernova often explodes inside a dense circumstellar medium, which is established due to the progenitor star losing its outermost envelope in a stellar wind or mass transfer in a binary system. The nature of the circumstellar medium and the ejecta of the supernova and their dynamics are revealed by observations in the optical, IR, radio, and X-ray bands, and I discuss some of these observations and their interpretations.Comment: To be published in " Principles and Perspectives in Cosmochemistry" Lecture Notes on Kodai School on Synthesis of Elements in Stars; ed. by Aruna Goswami & Eswar Reddy, Springer Verlag, 2009. Contains 21 figure