Raman-active modes in defective peapod

International audienceThe vibrational properties of defective single-walled carbon nanotube filled with C60 fullerene is the subject of the current study. For this aim we use the spectral moments method in the framework of the bond-polarization theory to calculate the nonresonant Raman spectra of hexa-vacancy defective C60 peapods. Essentially, the vibrational properties are closely coupled with the atomic structure of the system. The evolution of the Raman spectrum as a function of the spatial arrangement of defects in carbon nanotubes is discussed. This work provides benchmark theoretical results to understand the experimental data of defective C60 peapod

EFFECT OF GIBBERELLIC ACID ON THE PERSISTENCE OF CERTAIN PESTICIDES ON/IN GRAPE FRUITS

Recommended application was done by spray regime for two pesticides, namely diniconazole, fenitrothion and a plant growth regulator (gibberellic acid) and their mixtures. Their residues were determined after different successive treatments in and on grape fruits in two consecutive years. The initial deposits of the fungicide diniconazole when used alone were 0.49 and 0.50 ppm for 2006 and 2007, respectively.  While the initial deposits of fenitrothion reached to 11.35 and 11.19 ppm for the same interval, respectively. Initial deposits of the plant growth regulator gibberellic acid were 30.52 and 30.42 ppm for the same period, respectively. After mixing the tested pesticides and the plant growth regulator, the initial deposits loss reached 38.77 and 42.0 % for diniconazole, 43.08 and 48.16 %  for fenitrothion and 6.88 and 7.00 %  for gibberellic acid for the same seasons, respectively. A significant degradation was recorded with the mixture of the two tested pesticides and plant growth regulator compared with that occurred when pesticide was used alone at the two studied seasons

INTERPRETATION OF THREE WHEAT CULTIVARS YIELD AND ITS COMPONENTS WITH REFERENCE TO SOWING DATES

Two field experiments were carried out in Agric. Expt. Farm at Shalakan, Kaleobia Governorate, Cairo, Egypt during 2010/2011 and 2011/2012 growing seasons to study the response of some bread wheat cultivars to sowing dates. Each experiment included 15 treatments which were the combination between three wheat cultivars (Giza 168, Sakha 93 and Gemmiza 9) and five sowing dates (1st October, 16th October, 1st November, 16th November and 1st December). The experimental design used was split plot design in 6 replications. The data revealed that sowing dates and cultivars both significantly affected wheat yield and its components. Sowing on 1st November exhibited significant maximum plant height, number of spike/m2, main spike length and weight, grains number of main spike as well as grain, straw and biological yields as compared to early or late sowing in the season. Concerning wheat cultivars, Gemmiza 9 gave significantly highest yield and its components in comparison to Sakha 93 and Giza 168. The effect of the interaction between wheat cultivars and sowing dates were significantly differed in plant height, main spike length and weight, grain weight/spike as well as grain, straw and biological yields as well as GCPY. Gemmiza 9 exhibited the significant highest parameters when sown on 1st November as compared to the other studied two cultivars. The data revealed that sowing Gemmiza 9 wheat cultivar on 1st November was the most suitable environmental conditions for growing wheat in Kaluobia Governorate

Assessment of Bacteriological Quality of Drinking Water from Various Sources in Tukarah Town, NE Libya

The aim of this study was to evaluate drinking water quality in 21 water sources categorized in three levels. Samples of water were collected from each source for bacteriological examination. The results show there was a significant difference between the three levels 1, 2, and 3 for total coliform and fecal coliform bacteria with p-values (0.026) and (0.003) respectively. Presence of total coliform and fecal coliform bacteria were not reported from level 3 and was zero MPN per 100 ml. However, the high contamination by total coliform and fecal coliform bacteria were observed in samples collected from levels 1 and 2, these were in the range of 2 to 350 MPN/100 ml, 2 to 26 MPN/100 ml respectively. On the other hand, the biochemical identification process using Phoenix identified technique for the six isolated strains as Cedecea lapagel (DW4), Citrobacter freundii (DW9), Ochrobacterum anthroi (DW10) Pseudomonas aeruginosa (S10), Stenotrophomonas maltophilia (DW4) and Streptococcus anginosus (DW2), with confidence value identities of 90%, 99%, 90%, 95%, 99% and 91%  respectively. The findings showed that water from levels 1 and 2 did not conform to the world health organization (WHO) standard in terms of suitability for drinking purpose.Keywords: drinking water quality, coliform and fecal coliform bacteria, MPN/100ml

Measurement of 222Rn dissolved in water at the Sudbury Neutrino Observatory

The technique used at the Sudbury Neutrino Observatory (SNO) to measure the concentration of 222Rn in water is described. Water from the SNO detector is passed through a vacuum degasser (in the light water system) or a membrane contact degasser (in the heavy water system) where dissolved gases, including radon, are liberated. The degasser is connected to a vacuum system which collects the radon on a cold trap and removes most other gases, such as water vapor and nitrogen. After roughly 0.5 tonnes of H2O or 6 tonnes of D2O have been sampled, the accumulated radon is transferred to a Lucas cell. The cell is mounted on a photomultiplier tube which detects the alpha particles from the decay of 222Rn and its daughters. The overall degassing and concentration efficiency is about 38% and the single-alpha counting efficiency is approximately 75%. The sensitivity of the radon assay system for D2O is equivalent to ~3 E(-15) g U/g water. The radon concentration in both the H2O and D2O is sufficiently low that the rate of background events from U-chain elements is a small fraction of the interaction rate of solar neutrinos by the neutral current reaction.Comment: 14 pages, 6 figures; v2 has very minor change

Characterization of the Role of NKA in the Control of Puberty Onset and Gonadotropin Release in the Female Mouse.

The tachykinin neurokinin B (NKB, Tac2) is critical for proper GnRH release in mammals, however, the role of the other tachykinins, such as substance P (SP) and neurokinin A (NKA) in reproduction, is still not well understood. In this study, we demonstrate that NKA controls the timing of puberty onset (similar to NKB and SP) and stimulates LH release in adulthood through NKB-independent (but kisspeptin-dependent) mechanisms in the presence of sex steroids. Furthermore, this is achieved, at least in part, through the autosynaptic activation of Tac1 neurons, which express NK2R (Tacr2), the receptor for NKA. Conversely, in the absence of sex steroids, as observed in ovariectomy, NKA inhibits LH through a mechanism that requires the presence of functional receptors for NKB and dynorphin (NK3R and KOR, respectively). Moreover, the ability of NKA to modulate LH secretion is absent in Kiss1KO mice, suggesting that its action occurs upstream of Kiss1 neurons. Overall, we demonstrate that NKA signaling is a critical component in the central control of reproduction, by contributing to the indirect regulation of kisspeptin release

Tachykinin signaling is required for the induction of the preovulatory LH surge and normal LH pulses.

Tachykinins (NKA, NKB and Substance P) are important components of the neuroendocrine control of reproduction by directly stimulating Kiss1 neurons to control GnRH pulsatility, essential for reproduction. Despite this role of tachykinins for successful reproduction, knockout mice for Tac1 (NKA/SP) and Tac2 (NKB) genes are fertile, resembling the phenotype of human patients bearing NKB signaling mutations, who often reverse their hypogonadal phenotype. This suggests the existence of compensatory mechanisms among the different tachykinin ligand-receptor systems, to maintain reproduction in the absence of one of them. In order to test this hypothesis, we generated complete tachykinin deficient mice (Tac1/Tac2KO). Male mice displayed delayed puberty onset and decreased LH pulsatility (frequency and amplitude of LH pulses) but preserved fertility. However, females did not show signs of puberty onset (first estrus) within 45 days after vaginal opening, displayed low frequency (but normal amplitude) of LH pulses and 80% of them remained infertile. Further evaluation identified a complete absence of the preovulatory LH surge in Tac1/Tac2KO females as well as in WT females treated with NKB or SP receptor antagonists. These data confirmed a fundamental role for tachykinins in the timing of puberty onset and LH pulsatility and uncovered a role of tachykinin signaling in the facilitation of the preovulatory LH surge. Overall, these findings indicate that tachykinin signaling plays a dominant role in the control of ovulation, with potential implications as pathogenic mechanism and therapeutic target to improve reproductive outcomes in women with ovulation impairments

A Search for Neutrinos from the Solar hep Reaction and the Diffuse Supernova Neutrino Background with the Sudbury Neutrino Observatory

A search has been made for neutrinos from the hep reaction in the Sun and from the diffus

Low-Multiplicity Burst Search At The Sudbury Neutrino Observatory

Results are reported from a search for low-multiplicity neutrino bursts in the Sudbury Neutrino Observatory. Such bursts could indicate the detection of a nearby core-collapse supernova explosion. The data were taken from Phase I (1999 November-2001 May), when the detector was filled with heavy water, and Phase II (2001 July-2003 August), when NaCl was added to the target. The search was a blind analysis in which the potential backgrounds were estimated and analysis cuts were developed to eliminate such backgrounds with 90% confidence before the data were examined. The search maintained a greater than 50% detection probability for standard supernovae occurring at a distance of up to 60 kpc for Phase I and up to 70 kpc for Phase II. No low-multiplicity bursts were observed during the data-taking period.Natural Sciences and Engineering Research Council, CanadaIndustry Canada, CanadaNational Research Council, CanadaNorthern Ontario Heritage Fund, CanadaAtomic Energy of Canada, Ltd., CanadaOntario Power Generation, CanadaHigh Performance Computing Virtual Laboratory, CanadaCanada Foundation for Innovation, CanadaCanada Research Chairs, CanadaDepartment of Energy, USNational Energy Research Scientific Computing Center, USAlfred P. Sloan Foundation, USScience and Technology Facilities Council, UKFundacao para a Ciencia e a Technologia, PortugalAstronom