424 research outputs found
Induction of mitotic and meiotic gynogenesis and production of genetic clones in rohu, Labeo rohita Ham.
Studies were undertaken to produce genetic clones derived from all homozygous mitotic gynogenetic individuals in rohu, Labeo rohita Ham. ln view of this, attempts were made to interfere with the normal functioning of the spindle apparatus during the first mitotic cell division of developing eggs using heat shocks, there by leading to the induction of mitotic gynogenetic diploids in the F1 generation. Afterwards, viable mitotic gynogenetic alevins were reared and a selected mature female fish was used to obtain ovulated eggs which were fertilized later with UV-irradiated milt. Milt was diluted with Cortlandâs solution and the sperm concentration was maintained at 10âž/ml. The UV-irradiation was carried out for 2 minutes at the intensity of 200 to 250 ”W/cmÂČ at 28± 1°C. The optimal heat shock of 40°C for 2 minutes applied at 25 to 30 minutes a.f. was used to induce mitotic gynogenesis in first (F1) generation and at 3 to 5 minutes a.f. to induce meiotic
gynogenesis in the second (F2) generation. The results obtained are presented and the light they shed on the timing of the mitotic and meiotic cell division in this species is discussed
Digital wellbeing tools through users lens
There is a growing recognition of excessive, compulsive, and hasty use of technology as an emerging form of problematic behavior affecting individuals' emotional, social, and occupational wellbeing. Smartphone overuse, in particular, has been linked to negative effects on users' quality of life, such as anxiety, depression, sleep disturbance and loss in productivity. One strategy to help regulate digital usage and, potentially, increase digital wellbeing is to devise smartphone applications to collect data about usage and increase users' awareness of it and enable them to set limits and alert users accordingly. However, such applications have not been extensively evaluated from the users' perspective and whether they help the basic requirements for digital wellbeing. In this paper, we examine the quality of the emerging family of digital wellbeing smartphone applications from the users' perspective and based on persuasive design and established behavioral change theories. We performed a thematic analysis on the usersâ reviews on two popular applications, SPACE Break Phone Addiction and Google Digital Wellbeing (GDW). We report on the factors influencing user acceptance and rejection towards digital wellbeing applications and identify possible challenges and opportunities to improve their design and role in future releases
3-years later⊠a reassessment of the need for something âin-betweenâ
Welcome to the 2017 issue of INTER-SECTION: Innovative approaches by Junior Archaeological Researchers. In this issue, we present a total of five papers written by archaeology students in close collaboration with their academic referees, reflecting the wide range of both research and teaching at Leiden's Faculty of Archaeology from the the BA to the MA level
New Universality of Baryon Isgur--Wise Form Factor in the Large limit
New universality appears for the baryon Isgur--Wise form factor in the large
limit. It is found that the semileptonic and decays are described
by the same form factor, which can be calculated analytically. In the exact
chiral limit, the same form factor is applicable to semileptonic
decays.Comment: 5 pages in REVTEX galley style, CALT-68-194
Second Order Power Corrections in the Heavy Quark Effective Theory I. Formalism and Meson Form Factors
In the heavy quark effective theory, hadronic matrix elements of currents
between two hadrons containing a heavy quark are expanded in inverse powers of
the heavy quark masses, with coefficients that are functions of the kinematic
variable . For the ground state pseudoscalar and vector mesons, this
expansion is constructed at order . A minimal set of universal form
factors is defined in terms of matrix elements of higher dimension operators in
the effective theory. The zero recoil normalization conditions following from
vector current conservation are derived. Several phenomenological applications
of the general results are discussed in detail. It is argued that at zero
recoil the semileptonic decay rates for and receive only small second order corrections, which are unlikely
to exceed the level of a few percent. This supports the usefulness of the heavy
quark expansion for a reliable determination of .Comment: (34 pages, REVTEX, two postscript figures available upon request),
SLAC-PUB-589
\Omb \rightarrow \Omc , \Omc ^* $ transitions: Model-independent bounds on invariant form factors
In this note we report some model-independent bounds involving transition
form factors for \Omb \rightarrow \Omc and \Omb \rightarrow \Omc ^* and
the nonperturbative matrix elements of the \Omb system. They are derived by
using operator product expansion (OPE) in Heavy Quark Effective Theory .Comment: Latex, 7 page
Excited Baryons in the Large Limit
The spectrum of excited -type heavy baryons is considered in the
large limit. The universal form factors for semileptonic
decay to excited charmed baryons are calculated in the large limit. We
find that the Bjorken sum rule (for the slope of the Isgur--Wise function) and
Voloshin sum rule (for the mass of the light degrees of freedom) are saturated
by the first doublet of excited states.Comment: 9 pages, use phyzzx, CALT-68-191
Leptonic and Semileptonic Decays of Charm and Bottom Hadrons
We review the experimental measurements and theoretical descriptions of
leptonic and semileptonic decays of particles containing a single heavy quark,
either charm or bottom. Measurements of bottom semileptonic decays are used to
determine the magnitudes of two fundamental parameters of the standard model,
the Cabibbo-Kobayashi-Maskawa matrix elements and . These
parameters are connected with the physics of quark flavor and mass, and they
have important implications for the breakdown of CP symmetry. To extract
precise values of and from measurements, however,
requires a good understanding of the decay dynamics. Measurements of both charm
and bottom decay distributions provide information on the interactions
governing these processes. The underlying weak transition in each case is
relatively simple, but the strong interactions that bind the quarks into
hadrons introduce complications. We also discuss new theoretical approaches,
especially heavy-quark effective theory and lattice QCD, which are providing
insights and predictions now being tested by experiment. An international
effort at many laboratories will rapidly advance knowledge of this physics
during the next decade.Comment: This review article will be published in Reviews of Modern Physics in
the fall, 1995. This file contains only the abstract and the table of
contents. The full 168-page document including 47 figures is available at
http://charm.physics.ucsb.edu/papers/slrevtex.p
Comprehensive lung injury pathology induced by mTOR inhibitors
Molecular Targets in Oncology[Abstract] Interstitial lung disease is a rare side effect of temsirolimus treatment in renal cancer patients. Pulmonary fibrosis is characterised by the accumulation of extracellular matrix collagen, fibroblast proliferation and migration, and loss of alveolar gas exchange units. Previous studies of pulmonary fibrosis have mainly focused on the fibro-proliferative process in the lungs. However, the molecular mechanism by which sirolimus promotes lung fibrosis remains elusive. Here, we propose an overall cascade hypothesis of interstitial lung diseases that represents a common, partly underlying synergism among them as well as the lung pathogenesis side effects of mammalian target of rapamycin inhibitors
- âŠ