3,004 research outputs found
Relevance of unilateral and bilateral sexual polyploidization in relation to intergenomic recombination and introgression in Lilium species hybrids
Sexual polyploids were induced in diploid (2n = 2x = 24) interspecific F1 hybrids of Longiflorum × Asiatic (LA) and Oriental × Asiatic (OA) Lilium hybrids by backcrossing to Asiatic (AA) parents as well as by sib-mating of the F1 LA hybrids. A majority of the BC1 progenies were triploid and the progenies from sib-mating were tetraploid or near tetraploids. Genomic in situ hybridization (GISH) technique was applied to assess the intergenomic recombination in the BC1 populations of LA and OA hybrids obtained after unilateral sexual polyploidization. A total of 63 LA (LA × AA and AA × LA) and 53 OA hybrids were analysed. LA hybrids were originated through the functioning of 2n gametes either as 2n eggs or 2n pollen while those of OA hybrids originated through functional 2n pollen of diploid OA genotype. In both type of crosses, a majority of the progenies had originated through First Division Restitution (FDR) mechanism of functional 2n gamete either with or without a cross over. However, there were nine LA- and four OA-genotypes where Indeterminate Meiotic Restitution (IMR) was the mechanism of 2n gamete formation. Based on GISH, total amount of introgression of Longiflorum and Oriental genome into Asiatic genome was determined. Most of the BC progenies exhibited recombination and the amount of recombination was higher in LA hybrids as compared to OA hybrids. Intergenomic recombination was also determined cytologically in the 16 plants of sib-mated LA hybrids where both parents had contributed 2n gametes. Based on these results the nature of interspecific lily hybrids obtained from uni- and bilateral sexual polyploidization leading to allotriploid and allotetraploid formation is discussed in the context of introgression and intergenomic recombinatio
Security issues in 5G device to device communication
5G is a promising technology that will support high connectivity and device to device communication. It also promises to improve the existing technologies and will support them. Existing LTE-A utilize centralized communication scheme where all the authentication mechanisms need to go through the base station. This centralized authentication mechanism may generate authentication and key management overhead as well as computational complexity, thus not in line with the 5G requirements. On the other hand, distributed communication scheme lacks hop by hop authentication, thus, it is challenging to share the initial security credentials within the relay stations at multi-hop.
Secondly, distributed communication scheme required decode and forward relays, a partial intelligent relays that can act as a semi base stations. Such relays are known as non-transparent relays. However, inclusion of such intelligent relays can leads towards a ROGUE RELAY STATION (RRS) attacks, which consequently generate Replay attacks, DoS and the MITM (where mutual authentication is absent). RRS can generate interleaving attack even in the presence of mutual authentication
Deconfining transition in two-flavor QCD
The order and the nature of the finite-temperature phase transition of QCD
with two flavors of dynamical quarks is investigated. An analysis of the
critical exponent of the specific heat is performed through finite-size and
finite-mass scaling of various susceptibilities. Dual superconductivity of QCD
vacuum is investigated using a disorder parameter, namely the v.e.v. of a
monopole creation operator. Hybrid R simulations were run at lattice spatial
sizes of , , and and temporal size , with
quark masses in the range .Comment: Lattice2003(topology), 3 page
Quark helicity flip generalized parton distributions from two-flavor lattice QCD
We present an initiatory study of quark helicity flip generalized parton
distributions (GPDs) in n_f=2 lattice QCD, based on clover-improved Wilson
fermions for a large number of coupling constants and pion masses. Quark
helicity flip GPDs yield essential information on the transverse spin structure
of the nucleon. In this work, we show first results on their lowest moments and
dipole masses and study the corresponding chiral and continuum extrapolations.Comment: 15 pages, 6 figure
Generalized parton distributions and transversity from full lattice QCD
We present here the latest results from the QCDSF collaboration for moments
of generalized parton distributions and transversity in two-flavour QCD,
including a preliminary analysis of the pion mass dependence.Comment: Talks presented by Ph.Hagler and J.Zanotti at BARYONS 2004, Paris,
Oct. 25-29, 2004, 8 pages, 5 figure
Fabrication of Diamond Nanowires for Quantum Information Processing Applications
We present a design and a top-down fabrication method for realizing diamond
nanowires in both bulk single crystal and polycrystalline diamond. Numerical
modeling was used to study coupling between a Nitrogen Vacancy (NV) color
center and optical modes of a nanowire, and to find an optimal range of
nanowire diameters that allows for large collection efficiency of emitted
photons. Inductively coupled plasma (ICP) reactive ion etching (RIE) with
oxygen is used to fabricate the nanowires. Drop-casted nanoparticles (including
, and ) as well as electron
beam lithography defined spin-on glass and evaporated have been
used as an etch mask. We found nanoparticles to be the most
etch resistant. At the same time FOx e-beam resist (spin-on glass) proved to be
a suitable etch mask for fabrication of ordered arrays of diamond nanowires. We
were able to obtain nanowires with near vertical sidewalls in both
polycrystalline and single crystal diamond. The heights and diameters of the
polycrystalline nanowires presented in this paper are \unit[\approx1]{\mu m}
and \unit[120-340]{nm}, respectively, having a \unit[200]{nm/min} etch
rate. In the case of single crystal diamond (types Ib and IIa) nanowires the
height and diameter for different diamonds and masks shown in this paper were
\unit[1-2.4]{\mu m} and \unit[120-490]{nm} with etch rates between
\unit[190-240]{nm/min}.Comment: 11 pages, 26 figures, submitted to Diamond and related Materials;
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TWV-4Y7MM1M-1&_user=10&_coverDate=01%2F25%2F2010&_rdoc=1&_fmt=high&_orig=search&_sort=d&_docanchor=&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=6dc58b30f4773a710c667306fc541cc
Neurodegenerative and functional signatures of the cerebellar cortex in m.3243A \u3e G patients
Mutations of the mitochondrial DNA are an important cause of inherited diseases that can severely affect the tissue\u27s homeostasis and integrity. The m.3243A \u3e G mutation is the most commonly observed across mitochondrial disorders and is linked to multisystemic complications, including cognitive deficits. In line with in vitro experiments demonstrating the m.3243A \u3e G\u27s negative impact on neuronal energy production and integrity, m.3243A \u3e G patients show cerebral grey matter tissue changes. However, its impact on the most neuron dense, and therefore energy-consuming brain structure - the cerebellum - remains elusive. In this work, we used high-resolution structural and functional data acquired using 7 T MRI to characterize the neurodegenerative and functional signatures of the cerebellar cortex in m.3243A \u3e G patients. Our results reveal altered tissue integrity within distinct clusters across the cerebellar cortex, apparent by their significantly reduced volume and longitudinal relaxation rate compared with healthy controls, indicating macroscopic atrophy and microstructural pathology. Spatial characterization reveals that these changes occur especially in regions related to the frontoparietal brain network that is involved in information processing and selective attention. In addition, based on resting-state functional MRI data, these clusters exhibit reduced functional connectivity to frontal and parietal cortical regions, especially in patients characterized by (i) a severe disease phenotype and (ii) reduced information-processing speed and attention control. Combined with our previous work, these results provide insight into the neuropathological changes and a solid base to guide longitudinal studies aimed to track disease progression
Hybrid Monte Carlo with Fat Link Fermion Actions
The use of APE smearing or other blocking techniques in lattice fermion
actions can provide many advantages. There are many variants of these fat link
actions in lattice QCD currently, such as FLIC fermions. The FLIC fermion
formalism makes use of the APE blocking technique in combination with a
projection of the blocked links back into the special unitary group. This
reunitarisation is often performed using an iterative maximisation of a gauge
invariant measure. This technique is not differentiable with respect to the
gauge field and thus prevents the use of standard Hybrid Monte Carlo simulation
algorithms. The use of an alternative projection technique circumvents this
difficulty and allows the simulation of dynamical fat link fermions with
standard HMC and its variants. The necessary equations of motion for FLIC
fermions are derived, and some initial simulation results are presented. The
technique is more general however, and is straightforwardly applicable to other
smearing techniques or fat link actions
A lattice NRQCD calculation of the mixing parameter B_B
We present a lattice calculation of the B meson B-parameter B_B using the
NRQCD action. The heavy quark mass dependence is explicitly studied over a mass
range between m_b and 4m_b with the and actions. We
find that the ratios of lattice matrix elements and
, which contribute to B_B through mixing, have
significant dependence while that of the leading operator
has little effect. The combined result for
B_B(m_b) has small but non-zero mass dependence, and the B_B(m_b) becomes
smaller by 10% with the 1/m_Q correction compared to the static result. Our
result in the quenched approximation at \beta=5.9 is B_{B_d}(5 GeV) =
0.75(3)(12), where the first error is statistical and the second is a
systematic uncertainty.Comment: 20 pages, 11 figures, uses REVTeX, typos correcte
Gravitational Collapse: Expanding and Collapsing Regions
We investigate the expanding and collapsing regions by taking two well-known
spherically symmetric spacetimes. For this purpose, the general formalism is
developed by using Israel junction conditions for arbitrary spacetimes. This
has been used to obtain the surface energy density and the tangential pressure.
The minimal pressure provides the gateway to explore the expanding and
collapsing regions. We take Minkowski and Kantowski-Sachs spacetimes and use
the general formulation to investigate the expanding and collapsing regions of
the shell.Comment: 12 pages, 4 figures, accepted for publication in Gen. Relativ. Gra
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