2,385 research outputs found
An Improved Characterization of 1-Step Recoverable Embeddings: Rings in Hypercubes
An embedding is 1-step recoverable if any single fault occurs, the embedding can be reconfigured in one reconfiguration step to maintain the structure of the embedded graph. In this paper we present an efficient scheme to construct this type of 1-step recoverable ring embeddings in the hypercube. Our scheme will guarantee finding a 1-step recoverable embedding of a length-k (even) ring in a d-cube where 6 less than or equal to k less than or equal to (3/4)2/sup d/ and d greater than or equal to 3, provided such an embedding exists. Unlike previously proposed schemes, we solve the general problem of embedding rings of different lengths and the resulting embeddings are of smaller expansion than in previous proposals. A sufficient condition for the non-existence of 1-step recoverable embeddings of rings of length \u3e(3/4)2d in d-cubes is also give
CX3CR1+ interstitial dendritic cells form a contiguous network throughout the entire kidney
Dendritic cells (DCs) interface innate and adaptive immunity in nonlymphoid organs; however, the exact distribution and types of DC within the kidney are not known. We utilized CX3CR1GFP/+ mice to characterize the anatomy and phenotype of tissue-resident CX3CR1+ DCs within normal kidney. Laser-scanning confocal microscopy revealed an extensive, contiguous network of stellate-shaped CX3CR1+ DCs throughout the interstitial and mesangial spaces of the entire kidney. Intravital microscopy of the superficial cortex showed stationary interstitial CX3CR1+ DCs that continually probe the surrounding tissue environment through dendrite extensions. Flow cytometry of renal CX3CR1+ DCs showed significant coexpression of CD11c and F4/80, high major histocompatibility complex class II and FcR expression, and immature costimulatory but competent phagocytic ability indicative of tissue-resident, immature DCs ready to respond to environment cues. Thus, within the renal parenchyma, there exists little immunological privilege from the surveillance provided by renal CX3CR1+ DCs, a major constituent of the heterogeneous mononuclear phagocyte system populating normal kidney
Phosphoproteins and protein-kinase activity in isolated envelopes of pea (Pisum sativum L.) chloroplasts
A protein kinase was found in envelope membranes of purified pea (Pisum sativum L.) chloroplasts. Separation of the two envelope membranes showed that most of the enzyme activity was localized in the outer envelope. The kinase was activated by Mg2+ and inhibited by ADP and pyrophosphate. It showed no response to changes in pH in the physiological range (pH 7-8) or conventional protein substrates. Up to ten phosphorylated proteins could be detected in the envelope-membrane fraction. The molecular weights of these proteins, as determined by polyacrylamide-gel electrophoresis were: two proteins higher than 145 kDa, 97, 86, 62, 55, 46, 34 and 14 kDa. The 86-kDa band being the most pronounced. Experiments with separated inner and outer envelopes showed that most labeled proteins are also localized in the outer-envelope fraction. The results indicate a major function of the outer envelope in the communication between the chloroplast and the parent cell
Interpreting Helioseismic Structure Inversion Results of Solar Active Regions
Helioseismic techniques such as ring-diagram analysis have often been used to
determine the subsurface structural differences between solar active and quiet
regions. Results obtained by inverting the frequency differences between the
regions are usually interpreted as the sound-speed differences between them.
These in turn are used as a measure of temperature and magnetic-field strength
differences between the two regions. In this paper we first show that the
"sound-speed" difference obtained from inversions is actually a combination of
sound-speed difference and a magnetic component. Hence, the inversion result is
not directly related to the thermal structure. Next, using solar models that
include magnetic fields, we develop a formulation to use the inversion results
to infer the differences in the magnetic and thermal structures between active
and quiet regions. We then apply our technique to existing structure inversion
results for different pairs of active and quiet regions. We find that the
effect of magnetic fields is strongest in a shallow region above 0.985R_sun and
that the strengths of magnetic-field effects at the surface and in the deeper
(r < 0.98R_sun) layers are inversely related, i.e., the stronger the surface
magnetic field the smaller the magnetic effects in the deeper layers, and vice
versa. We also find that the magnetic effects in the deeper layers are the
strongest in the quiet regions, consistent with the fact that these are
basically regions with weakest magnetic fields at the surface. Because the
quiet regions were selected to precede or follow their companion active
regions, the results could have implications about the evolution of magnetic
fields under active regions.Comment: Accepted for publication in Solar Physic
The national cohort of dairy farms - a data collection platform for mastitis research in Canada
Entanglement, quantum phase transition and scaling in XXZ chain
Motivated by recent development in quantum entanglement, we study relations
among concurrence , SU(2) algebra, quantum phase transition and
correlation length at the zero temperature for the XXZ chain. We find that at
the SU(2) point, the ground state possess the maximum concurrence. When the
anisotropic parameter is deformed, however, its value decreases. Its
dependence on scales as in the XY metallic
phase and near the critical point (i.e. ) of the Ising-like
insulating phase. We also study the dependence of on the correlation length
, and show that it satisfies near the critical point. For
different size of the system, we show that there exists a universal scaling
function of with respect to the correlation length .Comment: 4 pages, 3 figures. to appear in Phys. Rev.
Majority versus minority dynamics: Phase transition in an interacting two-state spin system
We introduce a simple model of opinion dynamics in which binary-state agents
evolve due to the influence of agents in a local neighborhood. In a single
update step, a fixed-size group is defined and all agents in the group adopt
the state of the local majority with probability p or that of the local
minority with probability 1-p. For group size G=3, there is a phase transition
at p_c=2/3 in all spatial dimensions. For p>p_c, the global majority quickly
predominates, while for p<p_c, the system is driven to a mixed state in which
the densities of agents in each state are equal. For p=p_c, the average
magnetization (the difference in the density of agents in the two states) is
conserved and the system obeys classical voter model dynamics. In one dimension
and within a Kirkwood decoupling scheme, the final magnetization in a
finite-length system has a non-trivial dependence on the initial magnetization
for all p.ne.p_c, in agreement with numerical results. At p_c, the exact 2-spin
correlation functions decay algebraically toward the value 1 and the system
coarsens as in the classical voter model.Comment: 11 pages, 3 figures, revtex4 2-column format; minor revisions for
publication in PR
Acid-sensing ion channel 3 mediates peripheral anti-hyperalgesia effects of acupuncture in mice inflammatory pain
Background: Peripheral tissue inflammation initiates hyperalgesia accompanied by tissue acidosis, nociceptor activation, and inflammation mediators. Recent studies have suggested a significantly increased expression of acid-sensing ion channel 3 (ASIC3) in both carrageenan- and complete Freund's adjuvant (CFA)-induced inflammation. This study tested the hypothesis that acupuncture is curative for mechanical hyperalgesia induced by peripheral inflammation. Methods: Here we used mechanical stimuli to assess behavioral responses in paw and muscle inflammation induced by carrageenan or CFA. We also used immunohistochemistry staining and western blot methodology to evaluate the expression of ASIC3 in dorsal root ganglion (DRG) neurons. Results: In comparison with the control, the inflammation group showed significant mechanical hyperalgesia with both intraplantar carrageenan and CFA-induced inflammation. Interestingly, both carrageenan- and CFA-induced hyperalgesia were accompanied by ASIC3 up-regulation in DRG neurons. Furthermore, electroacupuncture (EA) at the ST36 rescued mechanical hyperalgesia through down-regulation of ASIC3 overexpression in both carrageenan- and CFA-induced inflammation. Conclusions: In addition, electrical stimulation at the ST36 acupoint can relieve mechanical hyperalgesia by attenuating ASIC3 overexpression
Surgical Treatment of Kawasaki Disease with Intestinal Pseudo-obstruction
A 5-year-old boy suffering from abdominal pain accompanied by a fever of up to 39.5 degrees C for 2 days was admitted to the hospital. Although Flomoxef was administered following admission, the boy's fever persisted and abdominal distension gradually worsened. On the 4th day, dry lips, red eyes and a strawberry tongue were noted. An echocardiogram revealed pericoronary enhancement with mild mitral valve regurgitation and a small degree of pericardial effusion, characteristics compatible with Kawasaki disease. Although intravenous immunoglobulin was administered, the fever and abdominal distension persisted. On the 8th day, a pediatric surgeon was consulted and an exploratory laparotomy was arranged. During the operation, intestinal pseudo-obstruction and fibrin coatings around the intestine near the splenic flexure were found. A colostomy was performed for decompression of the dilated bowel and a biopsy of the lymph node surrounding the splenic flexure was taken. The fever subsided dramatically after decompression of the bowel and the recovery course was uneventful. The pathologic report revealed necrotic lymphadenitis. We report this rare case and review the literature
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