61 research outputs found
The Bounds on the magnetic moment of the tau-neutrino via the process (e+e-)-->nunu(bar)gamma
Bounds on the anamolous magnetic moment of the tau neutrino are calculated
through the reaction (e+e-)-->nunu(bar)gamma at the neutral boson pole and in
the framework of an extended standard model, a left-right symmetric model and a
superstring-inspired model which has one extra low-energy neutral gauge boson.
The results are basedComment: 9 pages, 1 figure, 3 Table
Lorentz Violation in Extra Dimensions
In theories with extra dimensions it is well known that the Lorentz
invariance of the -dimensional spacetime is lost due to the compactified
nature of the dimensions leaving invariance only in 4d. In such theories
other sources of Lorentz violation may exist associated with the physics that
initiated the compactification process at high scales. Here we consider the
possibility of capturing some of this physics by analyzing the higher
dimensional analog of the model of Colladay and Kostelecky. In that scenario a
complete set of Lorentz violating operators arising from spontaneous Lorentz
violation, that are not obviously Planck-scale suppressed, are added to the
Standard Model action. Here we consider the influence of the analogous set of
operators which break Lorentz invariance in 5d within the Universal Extra
Dimensions picture. We show that such operators can greatly alter the
anticipated Kaluza-Klein(KK) spectra, induce electroweak symmetry breaking at a
scale related to the inverse compactification radius, yield sources of parity
violation in, e.g., 4d QED/QCD and result in significant violations of
KK-parity conservation produced by fermion Yukawa couplings, thus destabilizing
the lightest KK particle. LV in 6d is briefly discussed.Comment: 26 pages, 2 figures; additional references and discussio
The emerging role of non-coding RNAs in the regulation of PI3K/AKT pathway in the carcinogenesis process
The PI3K/AKT pathway is an intracellular signaling pathway with an indispensable impact on cell cycle control. This pathway is functionally related with cell proliferation, cell survival, metabolism, and quiescence. The crucial role of this pathway in the development of cancer has offered this pathway as a target of novel anti-cancer treatments. Recent researches have demonstrated the role of microRNAs (miRNAs) and long noncoding RNAs (lncRNAs) in controlling the PI3K/AKT pathway. Some miRNAs such as miR-155-5p, miR-328-3p, miR-125b-5p, miR-126, miR-331-3p and miR-16 inactivate this pathway, while miR-182, miR-106a, miR-193, miR-214, miR-106b, miR-93, miR-21 and miR-103/107 enhance activity of this pathway. Expression levels of PI3K/AKT-associated miRNAs could be used to envisage the survival of cancer patients. Numerous lncRNAs such as GAS5, FER1L4, LINC00628, PICART1, LOC101928316, ADAMTS9-AS2, SLC25A5-AS1, MEG3, AB073614 and SNHG6 interplay with this pathway. Identification of the impact of miRNAs and lncRNAs in the control of the activity of PI3K/AKT pathway would enhance the efficacy of targeted therapies against this pathway. Moreover, each of the mentioned miRNAs and lncRNAs could be used as a putative therapeutic candidate for the interfering with the carcinogenesis. In the current study, we review the role of miRNAs and lncRNAs in controlling the PI3K/AKT pathway and their contribution to carcinogenesis. © 2021 The Author(s
miR-1: A comprehensive review of its role in normal development and diverse disorders
MicroRNA-1 (miR-1) is a conserved miRNA with high expression in the muscle tissues. In humans, two discrete genes, MIRN1-1 and MIRN1-2 residing on a genomic region on 18q11.2 produce a single mature miRNA which has 21 nucleotides. miR-1 has a regulatory role on a number of genes including heat shock protein 60 (HSP60), Kruppel-like factor 4 (KLF4) and Heart And Neural Crest Derivatives Expressed 2 (HAND2). miR-1 has critical roles in the physiological processes in the smooth and skeletal muscles as well as other tissues, thus being involved in the pathogenesis of a wide range of disorders. Moreover, dysregulation of miR-1 has been noted in diverse types of cancers including gastric, colorectal, breast, prostate and lung cancer. In the current review, we provide the summary of the data regarding the role of this miRNA in the normal development and the pathogenic processes. © 2020 The Author(s
Spectral properties of the t-J model in the presence of hole-phonon interaction
We examine the effects of electron-phonon interaction on the dynamics of the
charge carriers doped in two-dimensional (2D) Heisenberg antiferromagnet. The
- model Hamiltonian with a Fr\"ohlich term which couples the holes to a
dispersionless (optical) phonon mode is considered for low doping
concentration. The evolution of the spectral density function, the density of
states, and the momentum distribution function of the holes with an increase of
the hole-phonon coupling constant is studied numerically. As the coupling
to a phonon mode increases the quasiparticle spectral weight decreases and a
``phonon satellite'' feature close to the quasi-particle peak becomes more
pronounced. Furthermore, strong electron-phonon coupling smears the
multi-magnon resonances (``string states'') in the incoherent part of the
spectral function. The jump in the momentum distribution function at the Fermi
surface is reduced without changing the hole pocket volume, thereby providing a
numerical verification of Luttinger theorem for this strongly interacting
system. The vertex corrections due to electron- phonon interaction are
negligible in spite of the fact that the ratio of the phonon frequency to the
effective bandwidth is not small.Comment: REVTeX, 20 pages, 9 figures, to be published in Phys. Rev. B (Nov. 1,
1996
Genetic analysis indicate superiority of perfomance of cape goosberry (Physalis peruviana L.) hybrids
The use of hybrids as a new type of cape gooseberry
(Physalis peruviana L.) cultivars could improve yield in this crop, but
little or no information is available on hybrid perfomance. We studied
several vegetative characters, yield, fruit weight and fruit shape, soluble
solids content (SSC), titratable acidity (TA) and ascorbic acid content
(AAC) in three hybrids of cape gooseberry and their parents grown outdoors
and in a glasshouse. The highest yields were obtained with hybrids,
specially in a glasshouse. Interaction dominance environment
for yield was very important; a higher dominance effect was detected in
the glasshouse, than that observed outdoors. Quality characters were
highly affected by the environment and showed variable results for the
different families. For fruit composition traits, the additive and additive
environment interactions were most important. Broad-sense heritability
for all characters was high to medium (0.48-0.91), indicating that a high
response to selection would be expected. Hybrids can improve cape
gooseberry yield without impairing fruit quality.Leiva-Brondo, M.; Prohens Tomás, J.; Nuez Viñals, F. (2001). Genetic analysis indicate superiority of perfomance of cape goosberry (Physalis peruviana L.) hybrids. Journal of New Seeds. 3(3):71-84. doi:10.1300/J153v03n03_04718433Abak, K., Güler, H. Y., Sari, N., & Paksoy, M. (1994). EARLINESS AND YIELD OF PHYSALIS (P. IXOCARPA BROT. AND P. PERUVIANA L.) IN GREENHOUSE, LOW TUNNEL AND OPEN FIELD. Acta Horticulturae, (366), 301-306. doi:10.17660/actahortic.1994.366.37Kang, M. S. (1997). Using Genotype-by-Environment Interaction for Crop Cultivar Development. Advances in Agronomy Volume 62, 199-252. doi:10.1016/s0065-2113(08)60569-6Klinac, D. J. (1986). Cape gooseberry (Physalis peruviana) production systems. New Zealand Journal of Experimental Agriculture, 14(4), 425-430. doi:10.1080/03015521.1986.10423060Mather, K., & Jinks, J. L. (1977). Introduction to Biometrical Genetics. doi:10.1007/978-94-009-5787-9Mazer, S. J., & Schick, C. T. (1991). Constancy of population parameters for life history and floral traits in Raphanus sativus L. I. Norms of reaction and the nature of genotype by environment interactions. Heredity, 67(2), 143-156. doi:10.1038/hdy.1991.74Nyquist, W. E., & Baker, R. J. (1991). Estimation of heritability and prediction of selection response in plant populations. Critical Reviews in Plant Sciences, 10(3), 235-322. doi:10.1080/07352689109382313Pearcy, R. W. (1990). Sunflecks and Photosynthesis in Plant Canopies. Annual Review of Plant Physiology and Plant Molecular Biology, 41(1), 421-453. doi:10.1146/annurev.pp.41.060190.002225Péron, J. Y., Demaure, E., & Hannetel, C. (1989). POSSIBILITIES OF TROPICAL SOLANACEAE AND CUCURBITACEAE INTRODUCTION IN FRANCE. Acta Horticulturae, (242), 179-186. doi:10.17660/actahortic.1989.242.24Proctor, F. J. (1990). THE EUROPEAN COMMUNITY MARKET FOR TROPICAL FRUIT AND FACTORS LIMITING GROWTH. Acta Horticulturae, (269), 29-40. doi:10.17660/actahortic.1990.269.
Induction of symmetrical nucleus division and multi-nucleate structures in microspores of eggplant (Solanum melongena L.) cultured in vitro
Effects of irradiation doses on haploid embryo and plant production in naked and shelled seed pumpkins
This study was carried out for two objectives: 1) to test efficiency of "pollination by irradiated pollen technique" in naked seed pumpkins (Cucurbita pepo var. styriaca) on parthenogenetic embryo stimulation and plant production compared to shelled seed genotypes (Cucurbita pepo var. pepo); and 2) to find the most suitable doses of irradiation both for naked and shelled seed pumpkins. As plant material, a total of 15 genotypes (ten naked and five shelled) were used and 3 irradiation doses of gamma rays (50, 100 and 150 Gy) were compared. During the study, a total of 2073 embryos were rescued from different genotypes and 979 of these developed into plants. Haploid embryos were obtained in all of the tested genotypes and no significant differences have been observed among genotypes. Although all of the three irradiation doses produced embryos and plants, more haploid plants were obtained from 150 Gy. 75 of the developed plants were acclimatized and cultivated in a polyethylene greenhouse and in 29 of these, ploidy levels were determined using indirect methods (existence of pollen, leaf and flower features, stoma density, chloroplast numbers in guard cells) and flow cytometry. As the result of the observations, 43% of these plants were found to be haploid and 57% were diploid. Haploid plant percentages were 36.7, 60.0 and 100.0% for 50, 100 and 150 Gy, respectively
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