464 research outputs found
Probing medium-induced jet splitting and energy loss in heavy-ion collisions
The nuclear modification of jet splitting in relativistic heavy-ion
collisions at RHIC and the LHC energies is studied based on the higher twist
formalism. Assuming coherent energy loss for the two splitted subjets, a
non-monotonic jet energy dependence is found for the nuclear modification of
jet splitting function: strongest modification at intermediate jet energies
whereas weaker modification for larger or smaller jet energies. Combined with
the smaller size and lower density of the QGP medium at RHIC than at the LHC,
this explains the CMS-STAR groomed jet puzzle -- strong nuclear modification of
the momentum sharing distribution at the LHC whereas no obvious
modification of the distribution at RHIC. In contrast, the observed
nuclear modification pattern of the groomed jet distribution cannot be
explained solely by independent energy loss of the two subjets. Our result may
be tested in future measurements of groomed jets with lower jet energies at the
LHC and larger jet energies at RHIC, for different angular separations between
the two subjets.Comment: 10 pages, 12 figure
CERKL gene knockout disturbs photoreceptor outer segment phagocytosis and causes rod-cone dystrophy in zebrafish
Addressless: A New Internet Server Model to Prevent Network Scanning
Eliminating unnecessary exposure is a principle of server security. The huge
IPv6 address space enhances security by making scanning infeasible, however,
with recent advances of IPv6 scanning technologies, network scanning is again
threatening server security. In this paper, we propose a new model named
addressless server, which separates the server into an entrance module and a
main service module, and assigns an IPv6 prefix instead of an IPv6 address to
the main service module. The entrance module generates a legitimate IPv6
address under this prefix by encrypting the client address, so that the client
can access the main server on a destination address that is different in each
connection. In this way, the model provides isolation to the main server,
prevents network scanning, and minimizes exposure. Moreover it provides a novel
framework that supports flexible load balancing, high-availability, and other
desirable features. The model is simple and does not require any modification
to the client or the network. We implement a prototype and experiments show
that our model can prevent the main server from being scanned at a slight
performance cost
Bifurcation in a Discrete Competition System
A new difference system is induced from a differential competition system by different discrete methods. We give theoretical analysis for local bifurcation of the fixed points and derive the conditions under which the local bifurcations such as flip occur at the fixed points. Furthermore, one- and two-dimensional diffusion systems are given when diffusion terms are added. We provide the Turing instability conditions by linearization method and inner product technique for the diffusion system with periodic boundary conditions. A series of numerical simulations are performed that not only verify the theoretical analysis, but also display some interesting dynamics
Pathogenic mutations in retinitis pigmentosa 2 predominantly result in loss of RP2 protein stability in humans and zebrafish
2018-2019 Master Class - Lynn Chang (Violin)
https://spiral.lynn.edu/conservatory_masterclasses/1176/thumbnail.jp
Ablation of EYS in zebrafish causes mislocalisation of outer segment proteins, F-actin disruption and cone-rod dystrophy
Mutations in EYS are associated with autosomal recessive retinitis pigmentosa (arRP) and autosomal recessive cone-rod dystrophy (arCRD) however, the function of EYS and the molecular mechanisms of how these mutations cause retinal degeneration are still unclear. Because EYS is absent in mouse and rat, and the structure of the retina differs substantially between humans and Drosophila, we utilised zebrafish as a model organism to study the function of EYS in the retina. We constructed an EYS-knockout zebrafish-line by TALEN technology which showed visual impairment at an early age, while the histological and immunofluorescence assays indicated the presence of progressive retinal degeneration with a cone predominately affected pattern. These phenotypes recapitulate the clinical manifestations of arCRD patients. Furthermore, the EYS(−/−) zebrafish also showed mislocalisation of certain outer segment proteins (rhodopsin, opn1lw, opn1sw1, GNB3 and PRPH2), and disruption of actin filaments in photoreceptors. Protein mislocalisation may, therefore, disrupt the function of cones and rods in these zebrafish and cause photoreceptor death. Collectively, these results point to a novel role for EYS in maintaining the morphological structure of F-actin and in protein transport, loss of this function might be the trigger for the resultant cellular events that ultimately lead to photoreceptor death
Exploration of Near-Horizon CFT Duality and in Conformal Weyl Gravity
We compute near horizon black hole entropy via the N\"other current method
within the conformal Weyl gravity paradigm for vacuum and non-vacuum
spacetimes. We do this, in the vacuum case, for the near horizon near extremal
Kerr metric and for the non-vacuum case we couple the conformal Weyl gravity
field equations to a near horizon (linear) gauge potential and analyze
the respective found solutions. We highlight the non-universality of black hole
entropy between black hole solutions of varying symmetries, yet their
congruence with Wald's entropy formula for the respective gravity theory.
Finally, we implement an construction to compute the full
asymptotic symmetry group of one of the non-vacuum conformal Weyl black holes.
We do this by performing a Robinson-Wilczek two dimensional reduction, thus
enabling the construction of an effective quantum theory of the remaining field
content. The effective stress energy tensor generates an asymptotic Virasoro
algebra, to -wave approximation, whose center in conjunction with their
proper regularized lowest Virasoro eigen-mode is implemented to compute black
hole entropy via the statistical Cardy formula. We additionally implement
quantum holomorphic fluxes (of the dual CFT) in the near horizon to compute the
Hawking temperature of the respective black hole spacetime. We conclude with a
discussion and outlook for future work.Comment: 20 pages, no figure
Physics perspectives of heavy-ion collisions at very high energy
Heavy-ion collisions at very high colliding energies are expected to produce
a quark-gluon plasma (QGP) at the highest temperature obtainable in a
laboratory setting. Experimental studies of these reactions can provide an
unprecedented range of information on properties of the QGP at high
temperatures. We report theoretical investigations of the physics perspectives
of heavy-ion collisions at a future high-energy collider. These include initial
parton production, collective expansion of the dense medium, jet quenching,
heavy-quark transport, dissociation and regeneration of quarkonia, photon and
dilepton production. We illustrate the potential of future experimental studies
of the initial particle production and formation of QGP at the highest
temperature to provide constraints on properties of strongly interaction
matter.Comment: 35 pages in Latex, 29 figure
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